Adhesion of human platelets to albumin is synergistically increased by lysophosphatidic acid and adrenaline in a donor-dependent fashion.

PubMed

Eriksson, Andreas C; Whiss, Per A; Nilsson, Ulrika K

2006-07-01

Lysophosphatidic acid (LPA) and adrenaline are weak platelet activators considered important for thrombus formation, and were previously shown to synergistically increase platelet aggregation. Here we investigate synergistic activation by LPA and adrenaline when measuring platelet adhesion. Platelet-rich plasma from healthy blood donors together with adrenaline and/or LPA were added to protein-coated microplates. Platelets were allowed to adhere and the amount of adhesion detected enzymatically. The LPA and adrenaline combination induced a synergistic increase of platelet adhesion to a normally non-adhesive albumin surface. The degree of synergy varied markedly between individuals; these variations could not be explained by age, gender, blood type or different amounts of platelets, oxidized low-density lipoprotein, insulin or glucose in plasma. There was a trend indicating increased synergistic effect for platelets sensitive to adrenaline stimulation. The synergistic effect was blocked by the alpha2-adrenoceptor antagonist yohimbine and inhibited by the ADP scavenger system creatine phosphate/creatine phosphokinase and antibodies against alphaIIbbeta3. Furthermore, platelets adhering to albumin after adrenaline and LPA treatment expressed P-selectin. In conclusion, LPA and adrenaline act synergistically to increase alphaIIbbeta3-mediated platelet adhesion to albumin, dependent on alpha2-adrenoceptor signalling and platelet secretion. We also confirm that synergistic platelet activation achieved with LPA and adrenaline is highly donor dependent.

Comparison of plateletpheresis on the Fresenius AS.TEC 204 and Haemonetics MCS 3p.

PubMed

Ranganathan, Sudha

2007-02-01

This is an attempt at comparing two cell separators for plateletpheresis, namely the Fresenius AS.TEC 204 and Haemonetics MCS 3p, at a tertiary care center in India. Donors who weighed between 55-75 kg, who had a hematocrit of 41-43%, and platelet counts of 250x10(3)-400x10(3)/microl were selected for the study. The comparability of the donors who donated on the two cell separators were analysed by t-test independent samples and no significant differences were found (P>0.05). The features compared were time taken for the procedure, volume processed on the separators, adverse reactions of the donors, quality control of the product, separation efficiency of the separators, platelet loss in the donors after the procedure, and the predictor versus the actual yield of platelets given by the cell separator. The volume processed to get a target yield of >3x10(11) was equal to 2.8-3.2 l and equal in both the cell separators. Symptoms of citrate toxicity were seen in 4 and 2.5% of donors who donated on the MCS 3p and the AS.TEC 204, respectively, and 3 and 1% of donors, respectively, had vasovagal reactions. All the platelet products collected had a platelet count of >3x10(11); 90% of the platelet products collected on the AS.TEC 204 attained the predicted yield that was set on the cell separator where as 75% of the platelet products collected on the MCS 3p attained the target yield. Quality control of the platelets collected on both the cell separators complied with the standards except that 3% of the platelets collected on the MCS 3p had a visible red cell contamination. The separation efficiency of the MCS 3p was higher, 50-52% as compared to the 40-45% on the AS.TEC 204. A provision of double venous access, less adverse reactions, negligible RBC contamination with a better predictor yield of platelets makes the AS.TEC 204 a safer and more reliable alternative than the widely used Haemonetics MCS 3p. Copyright (c) 2006 Wiley-Liss, Inc.

Abacavir has no prothrombotic effect on platelets in vitro.

PubMed

Diallo, Yacouba L; Ollivier, Véronique; Joly, Véronique; Faille, Dorothée; Catalano, Giovanna; Jandrot-Perrus, Martine; Rauch, Antoine; Yeni, Patrick; Ajzenberg, Nadine

2016-12-01

HIV patients exposed to abacavir have an increased risk of myocardial infarction, with contradictory results in the literature. The aim of our study was to determine whether abacavir has a direct effect on platelet activation and aggregation using platelets from healthy donors and from HIV-infected patients under therapy with an undetectable viral load. Platelet-rich plasma (PRP) or whole blood from healthy donors was treated with abacavir (5 or 10 μg/mL) or its active metabolite carbovir diphosphate. Experiments were also performed using blood of HIV-infected patients (n = 10) with an undetectable viral load. Platelet aggregation was performed on PRP by turbidimetry and under high shear conditions at 4000 s -1 . Platelet procoagulant potential was analysed by measuring thrombin generation by thrombinography. Abacavir and carbovir diphosphate significantly increased the aggregation of platelets from healthy donors induced by collagen at 2 μg/mL (P = 0.002), but not at 0.5 μg/mL. No effect of abacavir or carbovir diphosphate was observed on platelet aggregation induced by other physiological agonists or by high shear stress, or on thrombin generation. Pretreatment of blood from HIV-infected patients with abacavir produced similar results. Our results suggest that abacavir does not significantly influence platelet activation in vitro when incubated with platelets from healthy donors or from HIV-infected patients. It is, however, not excluded that a synergistic effect with other drugs could promote platelet activation and thereby play a role in the pathogenesis of myocardial infarction. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Influence of the direct NO-donor SIN-1 on the interaction between platelets and stainless steel stents under dynamic conditions.

PubMed

Jung, F; Mrowietz, C; Seyfert, U T; Grewe, R; Franke, R P

2003-01-01

It was investigated whether the NO-donor SIN-1, the active metabolite of molsidomine, influenced the activation of platelets, the formation of circulating platelet aggregates, the spontaneous aggregation of platelets and the activation of the clotting system triggered by a body foreign surface in an in vitro closed-loop perfusion model. With human platelet-rich plasma at micromolar concentrations SIN-1 exerted pronounced effects on the interaction between platelets and an exogenous surface. In the absence of SIN-1, the number of circulating single platelets decreased significantly, which could be due either to the formation of circulating platelet aggregates or to the adhesion of platelets to the stent. Both these processes were blocked by the addition of SIN-1. Moreover, the platelets exhibited hyperaggregability in the absence of SIN-1 whereas the NO-donor was able to completely inhibit spontaneous platelet aggregation. Similar results were obtained in flow cytometry experiments. Without SIN-1, high platelet surface densities of both the GPIb/IX and GPIIb/IIIa receptors were observed. In addition, the density of the fibrinogen receptor increased significantly with the number of perfusion cycles. SIN-1 was able to suppress the augmented GPIIb/IIIa receptor expression significantly. Molsidomine seemed to have the potential to reduce the incidence of thrombotic processes triggered by the exogenous surface of the stent.

Relative risk of reducing the lifetime blood donation deferral for men who have had sex with men versus currently tolerated transfusion risks.

PubMed

Vamvakas, Eleftherios C

2011-01-01

The risks of known and emerging transfusion-transmitted infections (TTIs) from reducing the current lifetime blood donation deferral for men who have had sex with men (MSM) to 1 or 5 years were compared to the risk from continuing to transfuse in the United States 12.5% of platelet doses as pooled whole-blood-derived (rather than single-donor) platelets. Assumptions made in mathematical models and blood donor/transfusion studies of the risks of TTIs since 2000 were evaluated. The number of HIV, hepatitis B virus, or hepatitis C virus TTIs from reducing the MSM deferral to 1 year is, respectively, 0.88, 2.94, or 66.9, many more than 10 times smaller than the risk from pooled platelets. If erroneous release of HIV-positive units (a risk independent of a donor's source of infection) is not considered, the MSM risk is 1 HIV-infectious donation per 17 to 56 million MSM donations. Any purportedly increased risk of human herpesvirus-8 transmission from MSM donors is far smaller than the risk of transfusion-associated sepsis from pooled platelets. Single-donor platelets from MSM after 5 years' abstinence are as safe or 5 times safer than our current pooled platelets--if the next TTI to emerge were transmitted, respectively, sexually or by another route. Thus, acceptance of MSM as blood donors after 1 or 5 years' abstinence may result in a postulated increase in risk that is so much smaller than the currently tolerated transfusion risk and so small in absolute terms that the ethical question of fairness to the MSM group justifies the change in policy. Copyright © 2011 Elsevier Inc. All rights reserved.

Autologous platelet-rich plasma gel to reduce donor-site morbidity after patellar tendon graft harvesting for anterior cruciate ligament reconstruction: a randomized, controlled clinical study.

PubMed

Cervellin, M; de Girolamo, L; Bait, C; Denti, M; Volpi, P

2012-01-01

Bone-patellar tendon-bone technique (BPTB) for anterior cruciate ligament injuries is associated with a higher risk of donor-site morbidity. To evaluate whether platelet-rich plasma (PRP), due to its anti-inflammatory properties and capacity to stimulate tissue regeneration, was able to reduce the anterior knee pain, the kneeling pain, and donor-site morbidity, as evidenced by evaluation of VISA and VAS scoring scales and MRI analysis of the tendon and bone defect, we performed a clinical randomized controlled study where PRP gel was applied to donor site after ACL reconstruction with BPTB. Forty young athletes with the indication of ACL reconstruction with patellar tendon grafts were randomly assigned to group A (n = 20 patients, control group) or group B (n = 20 patients, PRP group). The autologous PRP gel was applied to both the patellar and tendon bone plug harvest site and stabilized by the peritenon suture. At 12-month follow-up, all patients underwent clinical examination and VAS and VISA questionnaires, respectively, evaluating the average daily pain of the knee and the pain during particular activities involving the knee, were filled. MRI at the same time point was also performed. VISA scores were significantly higher in the patients treated with PRP (84.5 ± 11.8 and 97.8 ± 2.5 for group A and for group B; P = 0.041), whereas no significant difference in postoperative VAS scores between the two groups was observed (1 ± 1.4 and 0.6 ± 0.9 for group A and group B, n.s.). In 85% of PRP group patients, the tibial and patellar bone defect was satisfactorily filled by new bony tissue (>70% of bone gap filled), whereas this percentage was just of 60% in control group patients, but this difference was not statistically significant. The study shows the usefulness of PRP in reducing subjective pain at the donor-site level after ACL reconstruction with BPTB. However, this approach deserves further investigations to confirm PRP efficacy and to elucidate its mechanism of action. Prospective randomized controlled study, Level I.

[Analysis of genetic polymorphism in randomized donor's HPA 1-16 antigens and establishment of typed platelet donor data bank].

PubMed

Sun, Guo-Dong; Duan, Xian-Min; Zhang, Yan-Ping; Yin, Zhi-Zhu; Niu, Xiao-Li; Li, Yan-Feng; Niu, Hai-Jiang; Zhao, You-Liang

2005-10-01

To study the genetic polymorphism of HPA 1-16 platelet antigen alleles among unrelated volunteer donors and establish a typed platelet donor panel in Handan, typing was perfomed by polymerase chain reaction using sequence-specific primers (SSP-PCR); 148 random unrelated blood donors in Handan were genotyped for each of the HPA 1-16 antigen. The gene frequencies were analyzed and the genetype frequencies were determined by direct counting, and these data were compared with HPA distribution among various population by the chi-square test. The results indicated that HPA-1a, 2a, 4a-14a, 16a genes were found among the 16 HPAs in every sample tested. Monomorphic HPA-4a, 7a-14a, 16a were found in the samples. For HPA-1, 2, 5 and 6, a/a homozygosity was predominant with frequencies of 0.9595, 0.8108, 0.9865, 0.9797, respectively, and none of HPA b/b was found in the samples. HPA-1b, 2b, 5b, 6b were rarely found among subjects. HPA-15 had the greatest heterozygosity with a gene frequency of 0.2230, 0.5270, 0.2500 for HPA15a/15a, HPA15a/15b, HPA15b/15b, respectively. HPA-3 showed the second greatest heterozygosity with a gene frequency of 0.3851, 0.5135, 0.1014 for HPA3a/3a, HPA3a/3b, HPA3b/3b, respectively. HPA genotype frequencies showed a good fit to Hardy-Weinberg equilibrium. HPA1-5 gene frequencies for Chinese people in Handan were consistent with those of Chinese people in Shijiazhuang (P > 0.05). Among the HPA1-13, -15, the frequencies of HPA-1, -2, -6 for Chinese people in Handan differed appreciably from those for Chinese people in Taiwan (P < 0.05), others were similar to those of Chinese people in Taiwan. Among the HPA 1 - 8, a similarity was noted between Chinese people in Handan and Koreans (P > 0.05), except for HPA-3. Frequencies of HPA-1, -2, -5 significantly were differed from those in African Americans, as compared with HPA 1-5 (P < 0.05). Comparison of gene frequencies from HPA-1 and -5 showed significant differences between Chinese people in Handan and people in UK (P < 0.05). It is concluded that HPA-2, -3, -5, -15 of people in Western region of China have polymorphism, incompatible frequency of HPA antigen distribution is higher, which inevitably results in the increase of immunologic exposure, therefore attention must be paid to the importance of HPA-2, -3, -5, -15 in clinical disorders. This study for the first time completely analyses HPA1-16 gene frequencies in China, and provides data for establishing a typed platelet donor panel in Handan, China.

Platelet lysate obtained via plateletpheresis performed in standing and awake equine donors.

PubMed

Sumner, Scarlett M; Naskou, Maria C; Thoresen, Merrilee; Copland, Ian; Peroni, John F

2017-07-01

Platelet preparations containing growth factors, attachment factors, and enzymes are appealing to enhance healing of injured tissues and as an alternative to xenogenic serum in cell culture media. Plateletpheresis is commonly used to collect platelets in human medicine but has not been validated in horses. Plateletpheresis to collect platelet concentrate was performed on six female, mixed breed, chemically restrained horses using commercially available apheresis equipment. Before and immediately after plateletpheresis, we performed physical examinations and collected blood for chemistry and coagulation panels and then again at 8, 16, 24, and 48 hours after the procedure. To produce platelet lysate, the platelet concentrate underwent two freeze-thaw cycles followed by centrifugation and filtration processing. The platelet lysate was then analyzed for cellular debris, fibrinogen, and growth factors. The collected platelet concentration contained a mean platelet yield of 390 × 10 3 /μL. Donor platelet count decreased from a mean of 193 × 10 3 /μL to 138 × 10 3 /μL after plateletpheresis, but no individual was at risk for hemorrhage. Pooled platelet lysate had minimal cellular residue and contained growth factor concentrations at 6.1 ng/mL for transforming growth factor-β1, at 3.5 ng/mL for platelet-derived growth factor-BB, and at 13.8 ng/mL for vascular endothelial growth factor-A. Plateletpheresis using commercially available apheresis equipment is a feasible option for collecting platelet concentrate from equine donors. The lysate generated from the apheresis product contains growth factors and has potential to be used as a fetal bovine serum substitute for cell culture. © 2017 AABB.

Lea blood group antigen on human platelets.

PubMed

Dunstan, R A; Simpson, M B; Rosse, W F

1985-01-01

One- and two-stage radioligand assays were used to determine if human platelets possess the Lea antigen. Goat IgG anti-Lea antibody was purified by multiple adsorptions with Le(a-b-) human red blood cells, followed by affinity chromatography with synthetic Lea substance and labeling with 125I. Human IgG anti-Lea antibody was used either in a two stage radioassay with 125I-labeled mouse monoclonal IgG anti-human IgG as the second antibody or, alternatively, purified by Staph protein A chromatography, labeled with 125I, and used in a one-stage radioassay. Platelets from donors of appropriate red blood cell phenotypes were incubated with the antisera, centrifuged through phthalate esters, and assayed in a gamma scintillation counter. Dose response and saturation curve analysis demonstrate the presence of Lewis a antigen on platelets from Lea+ donors. Furthermore, platelets from an Le(a-b-) donor incubated in Le (a+b-) plasma adsorb Lea antigen in a similar manner to red blood cells. The clinical significance of these antigens in platelet transfusion remains undefined.

Comparative Analysis of Various Aspects of Plateletpheresis on the Fenwal Amicus and Fresenius COM.TEC Cell Separator Instruments.

PubMed

Philip, Joseph; Biswas, Amit Kumar; Chatterjee, Tathagata; Mallhi, Rajiv Singh

2014-01-01

To compare the Fenwal Amicus and the Fresenius COM.TEC apheresis instruments regarding donor peripheral blood parameters, operational variables of the instruments, and quality control parameters of the product obtained. We performed 100 platelet collections from 100 voluntary donors using the 2 studied devices. We measured platelet count using an automated analyzer and analyzed the activation statuses using a flow cytometer. The median time needed to perform the procedures was significantly longer with the COM.TEC. However, the product we obtained using the Amicus instrument showed higher degrees of platelet-activation. All products we obtained with both instruments had white blood cell counts of less than 5 × 10(6) per bag. We observed no statistical difference regarding collection efficiency and collection rates between the devices. Both instruments collected platelets efficiently, with minimal donor discomfort. Compared with the COM.TEC instrument, the Amicus reached the platelet target yield more quickly; however, it displayed an increase in platelet activation. Copyright© by the American Society for Clinical Pathology (ASCP).

A randomized controlled pilot trial of modified whole blood versus component therapy in severely injured patients requiring large volume transfusions.

PubMed

Cotton, Bryan A; Podbielski, Jeanette; Camp, Elizabeth; Welch, Timothy; del Junco, Deborah; Bai, Yu; Hobbs, Rhonda; Scroggins, Jamie; Hartwell, Beth; Kozar, Rosemary A; Wade, Charles E; Holcomb, John B

2013-10-01

To determine whether resuscitation of severely injured patients with modified whole blood (mWB) resulted in fewer overall transfusions compared with component (COMP) therapy. For decades, whole blood (WB) was the primary product for resuscitating patients in hemorrhagic shock. After dramatic advances in blood banking in the 1970s, blood donor centers began supplying hospitals with individual components [red blood cell (RBC), plasma, platelets] and removed WB as an available product. However, no studies of efficacy or hemostatic potential in trauma patients were performed before doing so. Single-center, randomized trial of severely injured patients predicted to large transfusion volume. Pregnant patients, prisoners, those younger than 18 years or with more than 20% total body surface area burns (TBSA) burns were excluded. Patients were randomized to mWB (1 U mWB) or COMP therapy (1 U RBC+ 1 U plasma) immediately on arrival. Each group also received 1 U platelets (apheresis or prepooled random donor) for every 6 U of mWB or 6 U of RBC + 6 U plasma. The study was performed under the Exception From Informed Consent (Food and Drug Administration 21 code of federal regulations [CFR] 50.24). Primary outcome was 24-hour transfusion volumes. A total of 107 patients were randomized (55 mWB, 52 COMP therapy) over 14 months. There were no differences in demographics, arrival vitals or laboratory values, injury severity, or mechanism. Transfusions were similar between groups (intent-to-treat analysis). However, when excluding patients with severe brain injury (sensitivity analysis), WB group received less 24-hour RBC (median 3 vs 6, P = 0.02), plasma (4 vs 6, P = 0.02), platelets (0 vs 3, P = 0.09), and total products (11 vs 16, P = 0.02). Compared with COMP therapy, WB did not reduce transfusion volumes in severely injured patients predicted to receive massive transfusion. However, in the sensitivity analysis (patients without severe brain injuries), use of mWB significantly reduced transfusion volumes, achieving the prespecified endpoint of this initial pilot study.

N-octanoyl-dopamine is a potent inhibitor of platelet function.

PubMed

Ait-Hsiko, Lamia; Kraaij, Tineke; Wedel, Johannes; Theisinger, Bastian; Theisinger, Sonja; Yard, Benito; Bugert, Peter; Schedel, Angelika

2013-01-01

Dopamine (DA) is a co-agonist for platelet activation; yet, donor DA treatment is associated with improved transplantation outcome in renal and heart recipients. Recently, N-octanoyl-dopamine (NOD) was developed which displays superior effects compared to DA in terms of graft protecting properties. Whereas DA is a known platelet co-agonist, the effect of NOD on platelet function is unknown. This is a hypothesis generating study with the aim to assess the effects and molecular mechanisms of NOD and NOD-like compounds on platelet function. The influence of DA, NOD, and NOD-like compounds on platelet responses to classical agonists (adenosine 5'-diphosphate (ADP), U46619) was investigated in six healthy donors by applying whole blood aggregometry (Multiplate®) and flow cytometry for Pac-1, CD62P, and CD63 expression. Changes in platelet cAMP concentrations were assessed by ELISA. While DA showed synergy in platelet activation by ADP and U46619, NOD caused significant inhibition of platelet function both in whole blood aggregometry and flow cytometry. The inhibitory effect of NOD was not mediated via cAMP levels. The nonredox-active NOD-analog N-octanoyl-tyramine had no effects on platelet function. Acetylated NOD conferred to NOD by intracellular esterases showed similar inhibitory effects as NOD. In contrast to DA, NOD is a potent inhibitor of platelet function most likely through intracellular redox-active processes. This adds to the overall protective effect of NOD on pre-transplantation injury and makes NOD an attractive candidate compound for donor or organ conditioning prior to transplantation.

Microparticle content of platelet concentrates is predicted by donor microparticles and is altered by production methods and stress.

PubMed

Maurer-Spurej, Elisabeth; Larsen, Rune; Labrie, Audrey; Heaton, Andrew; Chipperfield, Kate

2016-08-01

In circulation, shedding of microparticles from a variety of viable cells can be triggered by pathological activation of inflammatory processes, by activation of coagulation or complement systems, or by physical stress. Elevated microparticle content (MPC) in donor blood might therefore indicate a clinical condition of the donor which, upon transfusion, might affect the recipient. In blood products, elevated MPC might also represent product stress. Surprisingly, the MPC in blood collected from normal blood donors is highly variable, which raises the question whether donor microparticles are present in-vivo and transfer into the final blood component, and how production methods and post-production processing might affect the MPC. We measured MPC using ThromboLUX in (a) platelet-rich plasma (PRP) of 54 apheresis donors and the corresponding apheresis products, (b) 651 apheresis and 646 pooled platelet concentrates (PCs) with plasma and 414 apheresis PCs in platelet additive solution (PAS), and (c) apheresis PCs before and after transportation, gamma irradiation, and pathogen inactivation (N = 8, 7, and 12 respectively). ThromboLUX-measured MPC in donor PRP and their corresponding apheresis PC samples were highly correlated (r = 0.82, P = .001). The average MPC in pooled PC was slightly lower than that in apheresis PC and substantially lower in apheresis PC stored with PAS rather than plasma. Mirasol Pathogen Reduction treatment significantly increased MPC with age. Thus, MPC measured in donor samples might be a useful predictor of product stability, especially if post-production processes are necessary. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Standardization of a Protocol for Obtaining Platelet Rich Plasma from blood Donors; a Tool for Tissue Regeneration Procedures.

PubMed

Gómez, Lina Andrea; Escobar, Magally; Peñuela, Oscar

2015-01-01

To develop a protocol for obtaining autologous platelet rich plasma in healthy individuals and to determine the concentration of five major growth factors before platelet activation. This protocol could be integrated into the guidelines of good clinical practice and research in regenerative medicine. Platelet rich plasma was isolated by centrifugation from 38 healthy men and 42 women ranging from 18 to 59 years old. The platelet count and quantification of growth factors were analyzed in eighty samples, stratified for age and gender of the donor. Analyses were performed using parametric the t-test or Pearson's analysis for non-parametric distribution. P < 0.05 was considered statistically significant. Our centrifugation protocol allowed us to concentrate basal platelet counts from 1.6 to 4.9 times (mean = 2.8). There was no correlation between platelet concentration and the level of the following growth factors: VEGF-D (r = 0.009, p = 0.4105), VEGF-A (r = 0.0068, p = 0.953), PDGF subunit AA (p = 0.3618; r = 0.1047), PDGF-BB (p = 0.5936; r = 0.6095). In the same way, there was no correlation between donor gender and growth factor concentrations. Only TGF-β concentration was correlated to platelet concentration (r = 0.3163, p = 0.0175). The procedure used allowed us to make preparations rich in platelets, low in leukocytes and red blood cells, and sterile. Our results showed biological variations in content of growth factors in PRP. The factors influencing these results should be further studied.

Impairment of short-term memory associated with low iron stores in a volunteer multidose plateletpheresis donor.

PubMed

Page, E A; Harrison, J F; Jaldow, E J; Kopelman, M

2008-10-01

A platelet donor may lose 80-100 mL of blood both in the harness and by blood sampling at each donation, the equivalent of four to five whole blood donations per annum for a donor attending at 2-weekly intervals. A 54-year-old male multidose platelet donor had donated platelets at regular 2-weekly intervals for 6 years. He developed an impairment of anterograde memory (new learning). A self-rating scale revealed a moderate degree of depression [Beck Depression Inventory (BDI) score 22]. Memory testing (Doors and People Memory Battery) showed low scores, particularly for verbal recall and verbal recognition memory. He was found to have a normal haemoglobin of 157 g L(-1) with normal red blood cell indices, but a low serum ferritin (15 ng mL(-1)) and a low serum iron (8.1 mmol L(-1)). Following iron therapy and a return of his iron stores to normal levels, there was an improved BDI score of 13 (minimal level of depression) and a marked improvement in memory test scores. This has been maintained even though he has resumed platelet donation but at reduced intervals.

Donor Age of Human Platelet Lysate Affects Proliferation and Differentiation of Mesenchymal Stem Cells

PubMed Central

Lohmann, Michael; Walenda, Gudrun; Hemeda, Hatim; Joussen, Sylvia; Drescher, Wolf; Jockenhoevel, Stefan; Hutschenreuter, Gabriele; Zenke, Martin; Wagner, Wolfgang

2012-01-01

The regenerative potential declines upon aging. This might be due to cell-intrinsic changes in stem and progenitor cells or to influences by the microenvironment. Mesenchymal stem cells (MSC) raise high hopes in regenerative medicine. They are usually culture expanded in media with fetal calf serum (FCS) or other serum supplements such as human platelet lysate (HPL). In this study, we have analyzed the impact of HPL-donor age on culture expansion. 31 single donor derived HPLs (25 to 57 years old) were simultaneously compared for culture of MSC. Proliferation of MSC did not reveal a clear association with platelet counts of HPL donors or growth factors concentrations (PDGF-AB, TGF-β1, bFGF, or IGF-1), but it was significantly higher with HPLs from younger donors (<35 years) as compared to older donors (>45 years). Furthermore, HPLs from older donors increased activity of senescence-associated beta-galactosidase (SA-βgal). HPL-donor age did not affect the fibroblastoid colony-forming unit (CFU-f) frequency, immunophenotype or induction of adipogenic differentiation, whereas osteogenic differentiation was significantly lower with HPLs from older donors. Concentrations of various growth factors (PDGF-AB, TGF-β1, bFGF, IGF-1) or hormones (estradiol, parathormone, leptin, 1,25 vitamin D3) were not associated with HPL-donor age or MSC growth. Taken together, our data support the notion that aging is associated with systemic feedback mechanisms acting on stem and progenitor cells, and this is also relevant for serum supplements in cell culture: HPLs derived from younger donors facilitate enhanced expansion and more pronounced osteogenic differentiation. PMID:22662236

A Retrospective Analysis of Apheresis Donor Deferral and Adverse Reactions at a Tertiary Care Centre in India.

PubMed

Arora, Disha; Garg, Ketan; Kaushik, Ankit; Sharma, Richa; Rawat, D S; Mandal, A K

2016-11-01

With increasing demand of platelet component each day, blood bank plays a pivotal role in ensuring supply of safe blood as and when required. Plateletpheresis procedure is a relatively simple, safe and important adjunct to blood bank inventory. However, recruitment of healthy blood donors is a challenge that the health industry is facing today. To determine the reasons and rates of apheresis donor deferral along with investigation of adverse reactions encountered during the procedure. Records of single donor apheresis were retrospectively analysed from 1 st January 2010 to 31 st December 2014. The study was carried out at Blood Bank, Safdarjung Hospital, New Delhi, India. The donor details that were studied included - age, sex, type of donation (voluntary/replacement/ repeat), reason for donor deferral and type of adverse reaction, if encountered during the procedure. Among the 478 donors screened for plateletpheresis procedure during a study period of 5 years, 134 (28.03%) were deferred. Temporary deferrals accounted for majority (93.28%) of the deferrals. Low platelet count (50.75%) was the main reason of donor deferral followed by low haemoglobin (20.89%). Amongst the 344 selected donors, 15 (4.36%) had some type of adverse reaction associated with the procedure. We suggest that the selection criteria for plateletpheresis donors should be revised to deal with shortage of apheresis donors. The criteria regarding minimum pre-procedure platelet count (above1.5 lac/μl) and haemoglobin (above 12.5 g/dl) need to be lowered so as to suit the Indian scenario. The lower adverse reaction rates, 14/344 (4.06%) associated with this procedure encourages safety of donors and is important in recruitment of new donors.

Blood Facts and Statistics

MedlinePlus

... After What Happens to Donated Blood First Time Blood Donors Hosting a Blood Drive Manage My Blood Drive ... began collecting blood donations for patients in 1940 . Blood donors can give every 56 days . Platelet donors can ...

Recovery of Unrelated Donors of Peripheral Blood Stem Cells versus Bone Marrow: A Prespecified Analysis from the Phase III BMT CTN Protocol 0201

PubMed Central

Burns, Linda J.; Logan, Brent R.; Chitphakdithai, Pintip; Miller, John P.; Drexler, Rebecca; Spellman, Stephen; Switzer, Galen E.; Wingard, John R.; Anasetti, Claudio; Confer, Dennis L.

2016-01-01

We report a comparison of time to recovery, side effects, and change in blood counts from baseline to post-donation of unrelated donors who participated in the Blood and Marrow Transplant Clinical Trials Network (BMT CTN) phase III randomized, multicenter trial (0201) in which donor/recipient pairs were randomized to either peripheral blood stem cell (PBSC) or bone marrow (BM) donation. Of the entire cohort, 262 donated PBSC and 264 donated BM; 372 (71%) donors were from domestic and 154 (29%) from international centers (145 German and 9 Canadian). PBSC donors recovered in less time with a median time to recovery of 1 week compared to 2.3 weeks for BM donors. The number of donors reporting full recovery was significantly greater for donors of PBSC than of BM at 1, 2, and 3 weeks and 3 months post-donation. Multivariate analysis showed that PBSC donors were more likely to recover at any time post donation compared to BM donors (HR 2.08 [95% CI 1.73–2.50], p<0.001). Other characteristics that significantly increased the likelihood of complete recovery were being an international donor and donation in more recent years. Donors of BM were more likely to report grade 2–4 skeletal pain, body symptoms and fatigue at 1 week post donation. In logistic regression analysis of domestic donors only in which toxicities at peri-collection time points (day 5 filgrastim for PBSC donors and day 2 post-collection of BM donors) could be analyzed, no variable was significantly associated with grade 2–4 skeletal pain, including product donated (BM vs PBSC, OR 1.13 [95% CI 0.74–1.74], p=0.556). Blood counts were impacted by product donated, with mean change from baseline to post-donation being greater for white blood cells, neutrophils, mononuclear cells and platelets in PBSC donors whereas BM donors experienced a greater mean change in hemoglobin. This analysis provided an enhanced understanding of donor events as product donated was independent of physician bias or donor preference. PMID:27013014

Microparticles variability in fresh frozen plasma: preparation protocol and storage time effects.

PubMed

Kriebardis, Anastasios G; Antonelou, Marianna H; Georgatzakou, Hara T; Tzounakas, Vassilis L; Stamoulis, Konstantinos E; Papassideri, Issidora S

2016-05-01

Extracellular vesicles or microparticles exhibiting procoagulant and thrombogenic activity may contribute to the haemostatic potential of fresh frozen plasma. Fresh frozen plasma was prepared from platelet-rich plasma at 20 °C (Group-1 donors) or directly from whole blood at 4 °C (Group-2 donors). Each unit was aseptically divided into three parts, stored frozen for specific periods of time, and analysed by flow cytometry for procoagulant activity immediately after thaw or following post-thaw storage for 24 h at 4 °C. Donors' haematologic, biochemical and life-style profiles as well as circulating microparticles were analysed in parallel. Circulating microparticles exhibited a considerable interdonor but not intergroup variation. Fresh frozen plasma units were enriched in microparticles compared to plasma in vivo. Duration of storage significantly affected platelet- and red cell-derived microparticles. Fresh frozen plasma prepared directly from whole blood contained more residual platelets and more platelet-derived microparticles compared to fresh frozen plasma prepared from platelet-rich plasma. Consequently, there was a statistically significant difference in total, platelet- and red cell-derived microparticles between the two preparation protocols over storage time in the freezer. Preservation of the thawed units for 24 h at 4 °C did not significantly alter microparticle accumulation. Microparticle accumulation and anti-oxidant capacity of fresh frozen plasma was positively or negatively correlated, respectively, with the level of circulating microparticles in individual donors. The preparation protocol and the duration of storage in the freezer, independently and in combination, influenced the accumulation of microparticles in fresh frozen plasma units. In contrast, storage of thawed units for 24 h at 4 °C had no significant effect on the concentration of microparticles.

Nitric oxide decreases coagulation protein function in rabbits as assessed by thromboelastography.

PubMed

Nielsen, V G

2001-02-01

Nitric oxide (NO) is administered via infusion of donors such as nitroglycerin or in inhaled form for treatment of ischemia and pulmonary hypertension, respectively. In rabbits, the NO donor, DETANONOate, decreases whole blood clotting function as assessed by thromboelastographic variables (R, reaction time; alpha, angle; and G, a measure of clot strength). I hypothesized that DETANONOate-derived NO would adversely affect coagulation protein and platelet function. Blood obtained from ear arteries of conscious rabbits (n = 8) anticoagulated with sodium citrate. The blood was then incubated with 0 or 10mM DETANONOate for 30 min. After incubation and recalcification, thromboelastography was performed for 60 min under four conditions: 1) 0mM DETANONOate, 2) 0mM DETANONOate with platelet inhibition with cytochalasin D, 3) 10mM DETANONOate, and 4) 10mM DETANONOate with platelet inhibition. DETANONOate significantly (P < 0.05) increased R and decreased alpha and G in samples with or without platelet inhibition, compared with samples not exposed to DETANONOate. Lastly, the percentage of total G (G(T)) attributable to platelet function (G(P)) was significantly more in the absence of DETANONOate (G(P) = 92.3% +/- 1.6%; mean +/- SD) than after exposure to DETANONOate (G(P) = 90.2% +/- 2.3%). DETANONOate-derived NO significantly decreased coagulation protein function and platelet function. Coagulation protein function may be similarly affected in clinical situations involving the administration of NO or NO donors.

[Single-donor (apheresis) platelets and pooled whole-blood-derived platelets--significance and assessment of both blood products].

PubMed

Hitzler, Walter E

2014-01-01

The transfusion efficacy of ATK, which contain fully functional platelets, is beyond all doubt. The equivalence of ATK and PTK has been subject of many studies. Some of those studies show the superiority of ATK's, while others do not, but there have been no studies that demonstrated a superiority of PTK's. The superiority of platelets stored in plasma and in third generation additive solution was demonstrated in clinical studies; therefore, it cannot be said that all the platelet concentrates on the German market are equivalent in efficacy. Of decisive importance, above all, is the risk of transfusion-transmitted infections with known pathogens, or those not yet discovered. This risk is different for ATK compared to PTK. Taking this difference in risk and the difference in donor exposure of transfused patients into account, it can definitely be said that ATK and PTK are not equivalent. In 2012, the Robert-Koch-Institute (RKI) published a mathematical risk model for different platelet concentrates and assessed the risk of transmitting known pathogens such as HIV, HCV, and HBV. The risk was higher for PTK compared to ATK. The relative risks for PTK derived from 4BCs were 2.2 (95%--CI: 2.1-2.4) for HIV, 2.7 (95%--CI: 2.5-3.0) for HCV, and 2.2 (95%--CI: 2.8-3.7) for HBV. At the present time, these are the relative risks of transfusion-transmitted infections with the traditional pathogens for PTK compared to ATK. In addition to the RKI assessed risks, there is the theoretical risk of a new, unknown agent, transmitted through blood exposure. The magnitude of this risk is hardly predictable for PTK. The experience gathered so far, especially in the last three decades, with the emergence of HIV, prions, and West Nil virus, shows that the biological nature of a next transfusion-transmissible infectious agent cannot be predictable. This agent, if we think at a conventional sexually transmissible agent with nucleic acid and long latent period, would spread first in areas with high population density and thereby reduce the theoretical advantage of ATK (but definitely would not nullify it!). It is equally plausible, however, that this agent would behave like a prion, non-sexual transmission, or like a West-Nil virus, a non-contagious vector-transmitted agent. For PTK this would mean a relative risk up to 4 times (PTK from 4 BCs) or 5 times (PTK from 5 BCs) higher than the risk estimated by the Robert-Koch-Institute. If, taking the passive surveillance data and the changing variables (donor frequency, donor population, and donor location) into account, the risk of transmission of an infection via ATK (exposure to 1 donor) with HIV, HCV, and HBV moves closer to the higher risk of PTK (exposure to 4 or 8 donors, in case of double ATK per patient), this result of the risk model calculation by no means indicates any equivalency between PTK and ATK with respect to the risk of transmission of infection. The modifiable variables of donor frequency, donor population, and donor location need to be modified, as scientific deductions, in such a way that the avoidable risk of ATK which is influenced by these variables can be corrected to the minimum risk of a transmission of infection of HIV, HBV, and HCV via ATK in comparison to PTK. The minimum risk of a possible transmission of infection via ATK (exposure to 1 donor) is the basic intrinsic risk of each individual blood donation. The basic intrinsic risk increases relative to the number of blood donations or exposure to donors (PtK has an unalterable, production-dependent exposure to 4 or 8 donors). Let us consider a 1:1.000 prevalence for a new pathogen, which is spread equally in each donor population (apheresis and whole blood) and the present case of approximately 500,000 transfused platelet concentrates in Germany. This means that for the production of 4 PTK about 2 million donations are processed, 2,000 infectious Buffy-Coats are obtained and, thereby, 2,000 infectious PTK. In the case of ATK, considering five (5) donations per year, theoretically, it would mean 100 donors infected and 500 infectious ATK. Considering 15 apheresis donations per donor per year, this would mean that 33 donors are infected, but still 500 infectious ATK would be produced. The prion is an example of a pathogen that, although its existence is well known, cannot be proven or pathogen-reduced. In addition, it has a very long incubation period compared to the donation intervals. Due to the manufacturing process, PTK has a 4-fold higher donor exposure and therefore a 4-fold higher risk for transfusion-transmitted infections compared to ATK. If a patient needs the transfusion of two platelet concentrates, by transfusing a double-ATK from the same donor the risk of transfusion-transmitted infections will remain the same. On the other hand, the risk will increase by 8-fold by transfusing two PTK. The only current possibility to prevent or to minimize the risk of infection with prions is to minimize the donor exposure by transfusing ATK instead of PTK. Hypothetical risk scenarios carry significant weight in law. This can be seen in the constant rulings of the German Federal Supreme Court (Bundesgerichtshofs (BGH)) on the so-called hypothetical risk explanations (BGH, NJW 1996, 776, 777; 2000, 1784, 1787; 2005, 2614, 2616). Therefore, a risk does not need to be confirmed to be subject to compulsory explanation. It is sufficient that serious voices in the medical scientific community point to specific risks, which cannot be set aside as insignificant outside opinions, but must be viewed as serious warnings. According to the rulings, patients must even be informed of rare and often extremely rare risks, which could, should they come true, significantly impact daily life and, despite their rarity, are specific to the treatment and are startling for the ordinary person (BGH, 15.02.2000- VI ZR 48199 -; BGH, 30.11.2004 - VI ZR 209104 -; OLG Hamm, 29.09.2010 - 1-3 V 169109). These conditions have been fulfilled for PTK according to current knowledge, especially since, in the meantime in several rulings, the federal supreme court has required the reference to as yet unknown risks (refer to BGH, 13.06.2006 - VI ZR 323104 - for the use of new medical treatment methods, BGH, 27.06.2007 - VI ZR 55105 for experimental therapy using new, unapproved medication BGH, 06.07.2010 - VI ZR 198109 - for unknown risks cannot be excluded, for example based on anatomical conditions). ATK and PTK are therapeutic alternatives with the same range of indications for treatment using thrombocytes, however, with differing risks of infection, with different exposures to donors, and with different efficacy. ATK and PTK. ATK and PTK are therapeutic alternatives in terms of pharmaceutical law based on the different risks and the different quality. Patients must be informed of therapeutic alternatives such as ATK and PTK according to the patient rights law. Denial of reimbursement for additional fees for ATK by individual insurance companies (or paying authorities) deviates blatantly, as seen in the ruling of the Social Court of of the Saarland in this matter, from the basic requirement of the Transfusion Law (Transfusionsgesetz (TFG)) and is legally incorrect. The legality of the question whether the transfusion of ATK is indicated or if PTK had sufficed, is not allowable within the context of an MDK-Test according to subsection 275 ff. SGB V. The denial is a direct infringment on the treatment authority of the attending hospital physician and is illegal according to subsection 275 Abs. 5 SGBV. It is certainly possible to establish a full ATK supply and can be immediately realized by increasing donation rates from 5 to 8.3 apheresis donations per year in the current scenario of apheresis structure and donor population. The donation interval between two apheresis donations would be 49 days. A complete supply with ATK can also be immediately implemented by enlarging the donor population, keeping the current apheresis donation frequency. The donor pool must be increased by 24,576 donors, which means a 67% increase of the existing donor population. A transition to an ATK supply that can cover the entire demand can certainly be realized in a short period of time, while assuring a complete supply with PTK is not a realistic option. All existing studies advise taking extreme caution with any alternative to the current German gold standard for the treatment of hyporegenerative thrombocytopenia. A prophylactic transfusion of a non-pathogen-inactivated platelet concentrate with on average 3 x 10(11) platelets is recommended when the platelet count drops below the threshold of 10,000/microL. All other alternatives to this strategy show an increase in intracranial bleeding events. The existing studies on platelet dose (PLADO-Trial and StoP-Trial) do not recommend deviating from 3 x 10(11) platelets per unit. On the contrary, these studies demonstrate that the only practicable way is to individually correlate every platelet transfusion to the patient body surface. Considering the current knowledge, it is not justified to lower the standard dose and, for certain patient groups, to switch from prophylaxis to therapeutic platelet transfusion. Applying ATK or PTK with a lower platelet content and only for therapeutic purposes, could considerably increase the bleeding risk, especially for WHO grades III and IV. This will also affect all the patients who receive an induction treatment. Through pathogen reduction, in parallel with platelet loss (Apoptosis), the function of the treated platelets is impaired. Alternatively, the cell destruction caused during this process could result in a release of platelet microRNA directly into the supernatant or in microvesicles. This reduction of microRNA will affect the storage of the platelets. (ABSTRACT TRUNCATED)

Amotosalen: Allogeneic Cellular Immunotherapies system, INTERCEPT Plasma System, INTERCEPT Platelet System, S 59.

PubMed

2003-01-01

Adis CommentsCerus Corporation is developing a variety of pathogen-inactivation systems, based on its Helinx technology. Three of the systems include amotosalen [S 59] as the inactivation compound. Amotosalen is a light-activated, DNA-, RNA-crosslinking psoralen compound, which is used to neutralise pathogens. The systems that utilise amotosalen are called the INTERCEPT Platelet System, the INTERCEPT Plasma System and the Allogeneic Cellular Immunotherapies (ACIT) system. The INTERCEPT Platelet System and INTERCEPT Plasma System are two of the systems that make up Cerus' INTERCEPT Blood Systems. The other system is the INTERCEPT Red Blood Cell System, which contains S 303 as the inactivation compound rather than amotosalen. Cerus' Helinx technology is able to prevent replication of DNA or RNA that is present in pathogens but not in the blood components being treated (e.g. platelets and plasma). When added to the blood components, the inactivation agent (in this case amotosalen) crosses the membrane or cell wall of the pathogen. When activated by light, amotosalen binds to the nucleic acid of the pathogen and prevents replication. This process prevents infection. INTERCEPT Platelet System: Cerus developed its INTERCEPT Platelet System, in collaboration with Baxter Healthcare, for use in blood centres. Platelets are an essential component of the coagulation process and may be required by patients undergoing surgery, cancer chemotherapy, transplantation or with bleeding disorders. The system is made up of an illuminator device, a compound absorption device and a processing kit containing amotosalen. In October 2002, the two companies announced that CE Mark approval had been received for the illuminator device for the INTERCEPT trade mark Blood System. Application of this technology to platelets is the first to be approved. As it is a new technology, the system is currently undergoing process validation in accordance with European Blood Bank GMP requirements. This validation process is currently being conducted in Denmark, France, Germany, Sweden and the UK. Marketing approval applications for the INTERCEPT Platelet System have also been submitted in Australia and Canada. In addition, the regulatory submission process has begun in the US. A phase III trial (EuroSPRITE) has been conducted in 103 patients in Europe with pooled random donor platelets. The platelets were collected using the buffy coat process. Another two 20-patient clinical trials have also been conducted in Europe, as well as a 40-patient trial using platelets collected by an apheresis collection system. Cerus has also conducted a phase III trial (SPRINT) in the US. The trial was conducted in 671 patients and used platelets collected by Baxter's apheresis collection system. INTERCEPT Plasma System: Cerus is also developing the INTERCEPT Plasma System in collaboration with Baxter Healthcare. The system also combines amotosalen, an illumination device and a compound absorption device. The two companies are currently preparing regulatory applications for the INTERCEPT Plasma System for the US. This application will be followed by a submission for CE Mark designation in Europe. Patients undergoing surgery, or transplantation, or with bleeding disorders, may require transfusions of plasma, often to control bleeding. The type of plasma is stored in frozen form and is called fresh frozen plasma (FFP). The INTERCEPT Plasma System is currently in phase IIIc development in the US. Patient enrolment in the trial is still ongoing. The trial is comparing INTERCEPT trade mark Plasma System treated versus untreated FFP in 30 patients with thrombotic thrombocytopenic purpura. Allogeneic Cellular Immunotherapies system: Cerus is also investigating the potential of its Helinx technology to improve the outcome of bone marrow transplantation procedures (used to treat leukaemia and lymphoma) through the treatmatment for many forms of leukaemia and is most effective when the donor is very closely matched to the patient for the major human leucocyte antigen (HLA) groups. As part of the transplant procedure, patients receive donor T cells to improve engraftment of the bone marrow transplant and strengthen the patient's immune system. However, donor T cells expose the patient to a high risk of contracting graft-versus-host disease (GVHD) caused by the proliferation of donor T cells, which attack the patient's healthy tissue. GVHD has a high mortality rate. Cerus' ACIT system has been developed to decrease the stringency of matching donors to patients and to inhibit the ability of donor T cells to cause GVHD. Light-activated amotosalen binds and permanently crosslinks DNA, preventing replication and thus stopping proliferation of donor T cells. Phase I development is currently being conducted in this area in the US using amotosalen as the neutralising agent. Cerus completed a phase I study investigating the safety and tolerability of its ACIT system in 2001. The study was conducted in patients receiving closely matched allogeneic bone marrow transplants for leukaemia. The company is currently collaborating with the National Marrow Donor Program in order to conduct further clinical studies in patients receiving bone marrow transplants from unmatched donors. Cerus has development, manufacturing and marketing agreements with Baxter covering the INTERCEPT Blood Systems, which includes the INTERCEPT Platelet system, the INTERCEPT Plasma System, and the INTERCEPT Red Blood Cell System. Under the terms of the agreements the two companies usually share the very early development activities. Cerus then conducts preclinical and clinical trials, while Baxter is responsible for the development of the systems disposables and devices. Following commercialisation Cerus will supply amotosalen and Baxter will supply the other components of the system and market, sell and distribute the system In January 2001, Cereus announced that it has entered into a collaborative agreement with the Pharmaceutical Division of Kirin Brewery in Japan to develop and market products for stem cell transplantation based on Cerus' proprietary Helinx technology. Under terms of the agreement, Cerus and Kirin will jointly develop the products. Cerus has received an initial license fee of US dollar 1 million. In addition it may receive up to US dollar 11 million in future payments upon achievement of development milestones. Kirin will also fund all development expenses for the Asia-Pacific region and a portion of Cerus' development activities aimed at obtaining product approval in the US. Kirin will market the products in the Asia-Pacific region, including Japan, China, Korea and Australia, and Cerus will receive a specified share of product revenues. Cerus will retain marketing rights in the rest of the world, including the US and Europe.

21 CFR 640.21 - Suitability of donors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Platelets § 640.21 Suitability of donors. (a) Whole blood donors shall meet the criteria for suitability prescribed in § 640.3. (b) [Reserved] (c... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Suitability of donors. 640.21 Section 640.21 Food...

Use of platelet-rich plasma for patellar tendon and medial collateral ligament injuries: best current clinical practice.

PubMed

Andia, Isabel; Maffulli, Nicola

2015-02-01

Platelet-rich plasmas (PRPs) are complex molecular therapies prepared from the patient's own blood through minimal manipulation. Clinical studies examining the efficacy of PRPs to manage patellar tendinopathy and medial collateral ligament (MCL) injuries have been reviewed. We found three controlled trials, two of them randomized, and seven case series in the management of patellar tendinopathy. In addition, three other randomized studies showed that PRPs help to regenerate the patellar tendon harvest site for anterior cruciate ligament reconstruction and to reduce patellar donor site morbidity. On the other hand, the use of PRP in MCL injuries is reported in a single case study. Seven of the 11 studies used leukocyte and PRP which was buffered in four studies. Seven of the 11 studies applied two or three injections. Given the heterogeneity of PRP protocols and the paucity of high-quality data, the most effective approach to guide clinical decisions regarding patellar tendinopathy cannot be deduced from the present published studies. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Extravasated platelet aggregation in liver zone 3 may correlate with the progression of sinusoidal obstruction syndrome following living donor liver transplantation: A case report

PubMed Central

NAKANUMA, SHINICHI; MIYASHITA, TOMOHARU; HAYASHI, HIRONORI; TAJIMA, HIDEHIRO; TAKAMURA, HIROYUKI; TSUKADA, TOMOYA; OKAMOTO, KOICHI; SAKAI, SEISHO; MAKINO, ISAMU; KINOSHITA, JUN; NAKAMURA, KEISHI; OYAMA, KATSUNOBU; INOKUCHI, MASAFUMI; NAKAGAWARA, HISATOSHI; NINOMIYA, ITASU; KITAGAWA, HIROHISA; FUSHIDA, SACHIO; FUJIMURA, TAKASHI; OHTA, TETSUO

2015-01-01

Sinusoidal obstruction syndrome (SOS), previously known as veno-occlusive disease, is relatively rare subsequent to liver transplantation (LT). SOS refractory to medical therapy, however, can result in centrilobular fibrosis, portal hypertension and liver failure. Although sinusoidal endothelial cell damage around central venules (zone 3) occurs early in the development of SOS, the detailed mechanism of SOS development and its association with thrombocytopenia are not yet completely understood. The present report describes a patient who experienced SOS with unexplained thrombocytopenia following living donor LT. The progression of SOS resulted in graft dysfunction and the patient succumbed. The presence of platelets in the liver allograft was assayed immunohistochemically using antibody to the platelet marker cluster of differentiation 42b (platelet glycoprotein Ib). Platelet aggregates were found attached to hepatocytes along the sinusoid and within the cytoplasm of hepatocytes, particularly in zone 3. By contrast, no staining was observed in zone 1. These findings suggested that extravasated platelet aggregation in the space of Disse and the phagocytosis of platelets by hepatocytes were initiated by sinusoidal endothelial cell damage due to the toxicity of the immunosuppressant tacrolimus or a corticosteroid pulse, and that platelet activation and degranulation may be at least partially involved in the mechanism responsible for SOS. PMID:25780397

Namibia’s transition from whole blood–derived pooled platelets to single-donor apheresis platelet collections

PubMed Central

Pitman, John P.; Basavaraju, Sridhar V.; Shiraishi, Ray W.; Wilkinson, Robert; von Finckenstein, Bjorn; Lowrance, David W.; Marfin, Anthony A.; Postma, Maarten; Mataranyika, Mary; Sibinga, Cees Th. Smit

2015-01-01

BACKGROUND Few African countries separate blood donations into components; however, demand for platelets (PLTs) is increasing as regional capacity to treat causes of thrombocytopenia, including chemotherapy, increases. Namibia introduced single-donor apheresis PLT collections in 2007 to increase PLT availability while reducing exposure to multiple donors via pooling. This study describes the impact this transition had on PLT availability and safety in Namibia. STUDY DESIGN AND METHODS Annual national blood collections and PLT units issued data were extracted from a database maintained by the Blood Transfusion Service of Namibia (NAMBTS). Production costs and unit prices were analyzed. RESULTS In 2006, NAMBTS issued 771 single and pooled PLT doses from 3054 whole blood (WB) donations (drawn from 18,422 WB donations). In 2007, NAMBTS issued 486 single and pooled PLT doses from 1477 WB donations (drawn from 18,309 WB donations) and 131 single-donor PLT doses. By 2011, NAMBTS issued 837 single-donor PLT doses per year, 99.1% of all PLT units. Of 5761 WB donations from which PLTs were made in 2006 to 2011, a total of 20 (0.35%) were from donors with confirmed test results for human immunodeficiency virus or other transfusion-transmissible infections (TTIs). Of 2315 single-donor apheresis donations between 2007 and 2011, none of the 663 donors had a confirmed positive result for any pathogen. As apheresis replaced WB-derived PLTs, apheresis production costs dropped by a mean of 8.2% per year, while pooled PLT costs increased by an annual mean of 21.5%. Unit prices paid for apheresis- and WB-derived PLTs increased by 9 and 7.4% per year on average, respectively. CONCLUSION Namibia’s PLT transition shows that collections from repeat apheresis donors can reduce TTI risk and production costs. PMID:25727921

Recovery of Unrelated Donors of Peripheral Blood Stem Cells versus Recovery of Unrelated Donors of Bone Marrow: A Prespecified Analysis from the Phase III Blood and Marrow Transplant Clinical Trials Network Protocol 0201.

PubMed

Burns, Linda J; Logan, Brent R; Chitphakdithai, Pintip; Miller, John P; Drexler, Rebecca; Spellman, Stephen; Switzer, Galen E; Wingard, John R; Anasetti, Claudio; Confer, Dennis L

2016-06-01

We report a comparison of time to recovery, side effects, and change in blood counts from baseline to after donation from unrelated donors who participated in the Blood and Marrow Transplant Clinical Trials Network phase III randomized, multicenter trial (0201) in which donor-recipient pairs were randomized to either peripheral blood stem cell (PBSC) or bone marrow (BM) donation. Of the entire cohort, 262 donated PBSC and 264 donated BM; 372 (71%) donors were from domestic and 154 (29%) were from international centers (145 German and 9 Canadian). PBSC donors recovered in less time, with a median time to recovery of 1 week compared with 2.3 weeks for BM donors. The number of donors reporting full recovery was significantly greater for donors of PBSC than of BM at 1, 2, and 3 weeks and 3 months after donation. Multivariate analysis showed that PBSC donors were more likely to recover at any time after donation compared with BM donors (hazard ratio, 2.08; 95% confidence interval [CI], 1.73 to 2.50; P < .001). Other characteristics that significantly increased the likelihood of complete recovery were being an international donor and donation in more recent years. Donors of BM were more likely to report grades 2 to 4 skeletal pain, body symptoms, and fatigue at 1 week after donation. In logistic regression analysis of domestic donors only in which toxicities at peri-collection time points (day 5 filgrastim for PBSC donors and day 2 after collection of BM donors) could be analyzed, no variable was significantly associated with grades 2 to 4 skeletal pain, including product donated (BM versus PBSC; odds ratio, 1.13; 95% CI, .74 to 1.74; P = .556). Blood counts were affected by product donated, with greater mean change from baseline to after donation for white blood cells, neutrophils, mononuclear cells, and platelets in PBSC donors whereas BM donors experienced a greater mean change in hemoglobin. This analysis provided an enhanced understanding of donor events as product donated was independent of physician bias or donor preference. Copyright © 2016 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Hyperglycemia-Induced Platelet Activation in Type 2 Diabetes Is Resistant to Aspirin but Not to a Nitric Oxide–Donating Agent

PubMed Central

Gresele, Paolo; Marzotti, Stefania; Guglielmini, Giuseppe; Momi, Stefania; Giannini, Silvia; Minuz, Pietro; Lucidi, Paola; Bolli, Geremia B.

2010-01-01

OBJECTIVE Acute, short-term hyperglycemia enhances high shear stress–induced platelet activation in type 2 diabetes. Several observations suggest that platelets in type 2 diabetes are resistant to inhibition by aspirin. Our aim was to assess comparatively the effect of aspirin, a nitric oxide–donating agent (NCX 4016), their combination, or placebo on platelet activation induced by acute hyperglycemia in type 2 diabetes. RESEARCH DESIGN AND METHODS In a double-blind, placebo-controlled, randomized trial, 40 type 2 diabetic patients were allocated to 100 mg aspirin once daily, 800 mg NCX 4016 b.i.d., both of them, or placebo for 15 days. On day 15, 1 h after the morning dose, a 4-h hyperglycemic clamp (plasma glucose 13.9 mmol/l) was performed, and blood samples were collected before and immediately after it for platelet activation and cyclooxygenase-1 (COX-1) inhibition studies. RESULTS Acute hyperglycemia enhanced shear stress–induced platelet activation in placebo-treated patients (basal closure time 63 ± 7.1 s, after hyperglycemia 49.5 ± 1.4 s, −13.5 ± 6.3 s, P < 0.048). Pretreatment with aspirin, despite full inhibition of platelet COX-1, did not prevent it (−12.7 ± 6.9 s, NS vs. placebo). On the contrary, pretreatment with the NO donor NCX 4016, alone or in combination with aspirin, suppressed platelet activation induced by acute hyperglycemia (NCX 4016 +10.5 ± 8.3 s; NCX 4016 plus aspirin: +12.0 ± 10.7 s, P < 0.05 vs. placebo for both). Other parameters of shear stress–dependent platelet activation were also more inhibited by NCX 4016 than by aspirin, despite lesser inhibition of COX-1. CONCLUSIONS Acute hyperglycemia-induced enhancement of platelet activation is resistant to aspirin; a NO-donating agent suppresses it. Therapeutic approaches aiming at a wider platelet inhibitory action than that exerted by aspirin may prove useful in patients with type 2 diabetes. PMID:20299485

Impact of Blood Mixing and ABO Compatibility on Platelet-Leukocyte Aggregations and Platelet P-Selectin Expression: An in Vitro Study.

PubMed

Huang, Go-Shine; Hu, Mei-Hua; Lin, Tso-Chou; Tsai, Yi-Ting; Lin, Chih-Yuan; Ke, Hung-Yen; Zheng, Xu-Zhi; Lin, Yi-Chang; Tsai, Chien-Sung

2018-05-01

Effects of blood transfusions on platelet- and leukocyte-related inflammation are unclear. We simulated transfusion using in vitro blood mixing to evaluate platelet-leukocyte aggregations (PLA) and platelet P-selectin expression, and the mechanism of PLA. Donor packed red blood cells (pRBCs) were obtained from a blood bank. Recipient whole blood samples were obtained from patients undergoing cardiac surgery. Blood sample mixtures were divided into four groups: group M, cross-matched blood type mixing; group O, donor type O with other blood type mixing (A, B, or AB); group S, ABO type-specific uncross-matched blood mixing; and group I, ABO incompatibility mixing. Donor pRBCs were added to recipient blood to reach 1%, 5%, and 10% (vol/vol) concentrations. Blood sample mixtures were analyzed to determine the PLA; P-selectin expression; and leukocyte CD11a, CD11b, and CD18 subunits of integrin expression. Analysis of variance tests were used to analyze differences. PLA significantly increased only in groups O and I (P = 0.003 and P < 0.001). Subpopulations of leukocytes significantly increased in all groups. There were no significant differences among the four groups (P = 0.578) in PLA increase. Although there was no significant effect on P-selectin expression (P = 1.000) and leukocyte CD11a and CD18 expression (P = 0.999, P = 0.422) within and between the groups, there was an increase in CD11b expression (P = 0.018). Blood mixing can increase PLA, especially in platelet-neutrophil and platelet-monocyte aggregations, possibly through nonhemolytic reactions. The CD11b integrin with CD18 may play a role in the formation of PLA.

Analysis of Reparative Activity of Platelet Lysate: Effect on Cell Monolayer Recovery In Vitro and Skin Wound Healing In Vivo.

PubMed

Sergeeva, N S; Shanskii, Ya D; Sviridova, I K; Karalkin, P A; Kirsanova, V A; Akhmedova, S A; Kaprin, A D

2016-11-01

Platelet lysate prepared from donor platelet concentrate and pooled according to a developed technique stimulates migration of multipotent mesenchymal stromal cells of the human adipose tissue and promotes healing of the monolayer defect in cultures of human fibroblasts and multipotent mesenchymal stromal cells in vitro in concentrations close those of fetal calf serum (5-10%). Lysate of platelets from platelet-rich rat blood plasma stimulated healing of the skin defect by promoting epithelialization and granulation tissue formation. The regenerative properties of platelet lysate in vivo increased with increasing its concentration.

Blood group genotyping: from patient to high-throughput donor screening.

PubMed

Veldhuisen, B; van der Schoot, C E; de Haas, M

2009-10-01

Blood group antigens, present on the cell membrane of red blood cells and platelets, can be defined either serologically or predicted based on the genotypes of genes encoding for blood group antigens. At present, the molecular basis of many antigens of the 30 blood group systems and 17 human platelet antigens is known. In many laboratories, blood group genotyping assays are routinely used for diagnostics in cases where patient red cells cannot be used for serological typing due to the presence of auto-antibodies or after recent transfusions. In addition, DNA genotyping is used to support (un)-expected serological findings. Fetal genotyping is routinely performed when there is a risk of alloimmune-mediated red cell or platelet destruction. In case of patient blood group antigen typing, it is important that a genotyping result is quickly available to support the selection of donor blood, and high-throughput of the genotyping method is not a prerequisite. In addition, genotyping of blood donors will be extremely useful to obtain donor blood with rare phenotypes, for example lacking a high-frequency antigen, and to obtain a fully typed donor database to be used for a better matching between recipient and donor to prevent adverse transfusion reactions. Serological typing of large cohorts of donors is a labour-intensive and expensive exercise and hampered by the lack of sufficient amounts of approved typing reagents for all blood group systems of interest. Currently, high-throughput genotyping based on DNA micro-arrays is a very feasible method to obtain a large pool of well-typed blood donors. Several systems for high-throughput blood group genotyping are developed and will be discussed in this review.

The Blood Group A Genotype Determines the Level of Expression of the Blood Group A on Platelets But Not the Anti-B Isotiter

PubMed Central

Lehner, Barbara; Eichelberger, Beate; Jungbauer, Christof; Panzer, Simon

2015-01-01

Summary Background The extent of expression of the blood group A on platelets is controversial. Further, the relation between platelets' blood group A expression and the titers of isoagglutinins has not been thoroughly investigated, so far. Methods We evaluated the relation between the genotype with platelets' blood group A and H expression estimated by flow cytometry and the titers of isoagglutinins. Results The A expression varied between genotypes and within genotypes. However, the expression in A1 was stronger than in all other genotypes (p < 0.0001). An overlap of expression levels was apparent between homozygous A1A1 and heterozygous A1 individuals. Still, The A1A1 genotype is associated with a particularly high antigen expression (p = 0.009). Platelets' A expression in A2 versus blood group O donors was also significant (p = 0.007), but there was again an overlap of expression. The secretor status had only little influence on the expression (p = 0.18). Also, isoagglutinin titers were not associated with genotypes. Conclusion: To distinguish between A1 and A2 donors may reduce incompatible platelet transfusions and therefore be favorable on platelet transfusion increment. Clinical data are needed to support this notion. PMID:26733767

Platelet activation and aggregation by the opportunistic pathogen Cutibacterium (Propionibacterium) acnes

PubMed Central

Petersson, Frida; Kilsgård, Ola; Shannon, Oonagh

2018-01-01

Cutibacterium (Propionibacterium) acnes, considered a part of the skin microbiota, is one of the most commonly isolated anaerobic bacteria from medical implants in contact with plasma. However, the precise interaction of C. acnes with blood cells and plasma proteins has not been fully elucidated. Herein, we have investigated the molecular interaction of C. acnes with platelets and plasma proteins. We report that the ability of C. acnes to aggregate platelets is dependent on phylotype, with a significantly lower ability amongst type IB isolates, and the interaction of specific donor-dependent plasma proteins (or concentrations thereof) with C. acnes. Pretreatment of C. acnes with plasma reduces the lag time before aggregation demonstrating that pre-deposition of plasma proteins on C. acnes is an important step in platelet aggregation. Using mass spectrometry we identified several plasma proteins deposited on C. acnes, including IgG, fibrinogen and complement factors. Inhibition of IgG, fibrinogen or complement decreased C. acnes-mediated platelet aggregation, demonstrating the importance of these plasma proteins for aggregation. The interaction of C. acnes and platelets was visualized using fluorescence microscopy, verifying the presence of IgG and fibrinogen as components of the aggregates, and co-localization of C. acnes and platelets in the aggregates. Here, we have demonstrated the ability of C. acnes to activate and aggregate platelets in a bacterium and donor-specific fashion, as well as added mechanistic insights into this interaction. PMID:29385206

Platelet activation and aggregation by the opportunistic pathogen Cutibacterium (Propionibacterium) acnes.

PubMed

Petersson, Frida; Kilsgård, Ola; Shannon, Oonagh; Lood, Rolf

2018-01-01

Cutibacterium (Propionibacterium) acnes, considered a part of the skin microbiota, is one of the most commonly isolated anaerobic bacteria from medical implants in contact with plasma. However, the precise interaction of C. acnes with blood cells and plasma proteins has not been fully elucidated. Herein, we have investigated the molecular interaction of C. acnes with platelets and plasma proteins. We report that the ability of C. acnes to aggregate platelets is dependent on phylotype, with a significantly lower ability amongst type IB isolates, and the interaction of specific donor-dependent plasma proteins (or concentrations thereof) with C. acnes. Pretreatment of C. acnes with plasma reduces the lag time before aggregation demonstrating that pre-deposition of plasma proteins on C. acnes is an important step in platelet aggregation. Using mass spectrometry we identified several plasma proteins deposited on C. acnes, including IgG, fibrinogen and complement factors. Inhibition of IgG, fibrinogen or complement decreased C. acnes-mediated platelet aggregation, demonstrating the importance of these plasma proteins for aggregation. The interaction of C. acnes and platelets was visualized using fluorescence microscopy, verifying the presence of IgG and fibrinogen as components of the aggregates, and co-localization of C. acnes and platelets in the aggregates. Here, we have demonstrated the ability of C. acnes to activate and aggregate platelets in a bacterium and donor-specific fashion, as well as added mechanistic insights into this interaction.

CTLA4-Ig Prevents Alloantibody Production and BMT Rejection in Response to Platelet Transfusions in Mice

PubMed Central

Gilson, Christopher R; Patel, Seema R; Zimring, James C

2014-01-01

Background Platelet transfusions can induce humoral and cellular alloimmunity. Anti-HLA antibodies can render patients refractory to subsequent transfusion, and both alloantibodies and cellular alloimmunity can contribute to subsequent bone marrow transplant rejection. Currently, there are no approved therapeutic interventions to prevent alloimmunization to platelet transfusions other than leukoreduction. Targeted blockade of T cell costimulation has shown great promise in inhibiting alloimmunity in the setting of transplantation, but has not been explored in the context of platelet transfusion. Study Design and Methods We tested the hypothesis that the costimulatory blockade reagent CTLA4-Ig would prevent alloreactivity against major and minor alloantigens on transfused platelets. BALB/c (H-2d) mice and C57BL/6 (H-2b) mice were used as platelet donors and transfusion recipients, respectively. Alloantibodies were measured by indirect immunofluorescence using BALB/c platelets and splenocytes as targets. Bone marrow transplants were carried out under reduced intensity conditioning using BALB/b (H-2b) donors and C57BL/6 (H-2b) recipients to model HLA identical transplants. Experimental groups were given CTLA4-Ig (before or after platelet transfusion) with control groups receiving isotype matched antibody. Results CTLA4-Ig abrogated both humoral alloimmunization (anti-H-2d antibodies) and transfusion induced bone marrow transplant rejection. Whereas a single dose of CTLA4-Ig at time of transfusion prevented alloimmunization to subsequent platelet transfusions, administration of CTLA4-Ig after initial platelet transfusion was ineffective. Delaying treatment until after platelet transfusion failed to prevent bone marrow transplant rejection. Conclusions These findings demonstrate a novel strategy using an FDA approved drug that has the potential to prevent the clinical sequela of alloimmunization to platelet transfusions. PMID:22321003

Antimicrobial properties of single-donor-derived, platelet-leukocyte fibrin for fistula occlusion: An in vitro study.

PubMed

Wu, Xiuwen; Ren, Jianan; Yuan, Yujie; Luan, Jianfeng; Yao, Genhong; Li, Jieshou

2013-01-01

Fibrin glue is a promising alternative for low-output enterocutaneous fistula closure. Bacterial flora colonizing inside the fistula tract, however, may limit the glue application. Single-donor-derived, platelet-rich materials were hypothesized in this study to have antimicrobial activity against Gram-negative microorganisms. Platelet-leukocyte fibrin (PLF), platelet-rich plasma (PRP), and platelet-poor plasma (PPP) were obtained from healthy volunteers. The amounts of platelet, leukocyte, and complement/antibody were determined. In vitro laboratory susceptibility to PLF and plasmas was determined by the Kirby-Bauer disc-diffusion method. Antimicrobial activity of PLF, PRP, and PPP against three Gram-negative ATCC strains was determined in a bacterial kill assay. Levels of complement and antibody did not significantly differ among PLF, PRP, and PPP (p > 0.05), while platelet and leukocyte counts in platelet-rich biomaterials were significantly higher than those in PPP (p < 0.001). The bactericidal effects produced by PLF and PRP were more pronounced than those by PPP in both qualitative and quantitative aspects. No inhibitory zones against three Gram-negative organisms were observed in the Bioseal®. In conclusion, our homemade PLF, as compared with commercial products, had remarkable antimicrobial activity against Gram-negative bacteria relevant to fistula colonization. The presence of platelets and leukocytes may play an important role in bacterial defense. This is the first study to demonstrate the antibacterial properties of single-unit PLF for fistula closure, presenting a new opportunity for glue sealing.

Platelet concentrates for transfusion-metabolic and storage aspects.

PubMed

Farrugia, A

1994-01-01

Transfusion of platelets concentrated from donated blood is an established therapeutic modality in clinical medicine. Over the past 25 years much effort has gone into optimising the conditions for the collection, preparation and storage of platelets for transfusion. Despite significant advances, platelet production is still a costly process requiring a dedicated environment and the use of specially formulated plastic storage containers. A progressive lesion over storage limits the shelf life and the availability of donated platelets, while the need to store platelets in the donor's autologous plasma also results in a loss of valuable fresh plasma for fractionation. Recent studies have addressed the issues of platelet quality and plasma economy by examining the possibility of storing platelets in a synthetic medium. Platelets stored in a variety of crystalloid solutions have been shown to retain in vitro and in vivo properties equivalent or superior to platelets stored in autologous donor plasma. Some additional insight has been gained on the metabolic patterns of stored platelets. In particular, studies have shown that, under these conditions, platelets are unable to oxidise dextrose to any significant extent, and that dextrose is invariably broken down to lactate, irrespective of the oxygen tensions in the platelet's environment. This in turn leads to the metabolic lesion of platelet storage, whereby low pH results in loss of platelet viability. Platelets stored in synthetic dextrose-free media are capable of maintaining aerobic ATP generation, and acetate-a component of many media studied-has been shown to be metabolised by platelets. Similarly, platelets prepared from blood collected into a dextrose-free anticoagulant have satisfactory properties both when suspended in autologous plasma or in a dextrose-free synthetic medium. The requirements for storage in special, high gas-permeable, containers, and for constant agitation during storage, were both found to be unnecessary when dextrose was excluded from the platelet's environment. These developments suggest that manipulation of the platelet's metabolic pattern during blood bank storage may allow significant benefits in plasma economy as well as in decreasing the cost of platelet delivery to patients.

Allogeneic blood stem cell transplantation: considerations for donors.

PubMed

Anderlini, P; Körbling, M; Dale, D; Gratwohl, A; Schmitz, N; Stroncek, D; Howe, C; Leitman, S; Horowitz, M; Gluckman, E; Rowley, S; Przepiorka, D; Champlin, R

1997-08-01

Allogeneic transplantation of cytokine-mobilized peripheral blood stem cells (PBSCs) is now being increasingly performed, but safety considerations for hematologically normal PBSC donors have not been fully addressed. Progenitors are generally mobilized for collection from normal donors using recombinant human granulocyte colony-stimulating factor (rhG-CSF). Although the short-term safety profile of rhG-CSF seems acceptable, experience remains limited and its optimal dose and schedule have not been defined. Minimal data exist regarding long-term safety of rhG-CSF, primarily derived from experience in patients with chronic neutropenia or cancer. An "ad hoc" workshop was recently convened among a group of investigators actively involved in the field of allogeneic stem cell transplantation to discuss the safety issues pertaining to normal PBSC donors. There was agreement on the following points: (1) On the basis of available data, it appears that rhG-CSF treatment and PBSC collection have an acceptable short-term safety profile in normal donors. However, the need for continued safety monitoring was recognized. (2) rhG-CSF doses up to 10 microg/kg/d show a consistent dose-response relationship with the mobilization (and collection) of CD34+ progenitor cells, and this dose is acceptable for routine clinical use. Whether higher doses are superior (or cost effective) remains to be determined, and they may produce more severe side effects. The potential risks of marked leukocytosis (arbitrarily defined as a leukocyte count of more than 70 x 10(9)/L) have been a concern, and rhG-CSF dose reduction is performed by many centers to maintain leukocyte counts below this level. (3) Transient post donation cytopenias, involving granulocytes, lymphocytes, and platelets, may occur and are at least partly related to the leukapheresis procedure. These are generally asymptomatic and self-limited; follow-up blood counts are not necessarily required. Reinfusion of autologous platelet-rich plasma should be considered for donors with expected postdonation thrombocytopenia (platelet count < 80 to 100 x 10(9)/L). (4) Donors should meet the eligibility criteria which apply to donors of apheresis platelets, with the exception that pediatric donors may also be considered. Any deviation from these criteria should have supporting documentation. There is insufficient information at this time to clearly establish definite contraindications for PBSC collection in a hematologically normal donor. Potential contraindications include the presence of inflammatory, autoimmune, or rheumatologic disorders, as well as atherosclerotic or cerebrovascular disease. (5) The creation of an International PBSC Donor Registry is desirable to facilitate monitoring the long-term effects of the procedure. Individual institutions or donor centers are encouraged to establish their own PBSC donor follow-up system, preferably with a standardized approach to data collection.

Detection of HIT antibody dependent platelet aggregation using novel surface imprinting approach.

PubMed

Hussain, Munawar; Northoff, Hinnak; Gehring, Frank K

2016-01-15

We present a fast, robust and straightforward spin force assisted surface imprinting approach for activated platelets and demonstrate that Heparin induced thrombocytopenia (HIT) platelet aggregation can be measured by this approach. A critical and challenging step in functional assays for HIT is platelet separation from the healthy donor's platelet-rich plasma (PRP). Our approach using surface imprinted polymer (MIP) for measurements on a quartz crystal microbalance with dissipation (QCM-D) enables monitoring of platelet aggregation directly in PRP thus eliminating the challenge of platelet separation. This is the first report of platelet imprinting. We also provide proof of principle that QCM-D technology can be applied for functional measurements of HIT antibodies. Copyright © 2015 Elsevier B.V. All rights reserved.

Hair Transplantation Controversies.

PubMed

Avram, Marc R; Finney, Robert; Rogers, Nicole

2017-11-01

Hair transplant surgery creates consistently natural appearing transplanted hair for men. It is increasingly popular procedure to restore natural growing hair for men with hair loss. To review some current controversies in hair transplant surgery. Review of the English PubMed literature and specialty literature in hair transplant surgery. Some of the controversies in hair transplant surgery include appropriate donor harvesting technique including elliptical donor harvesting versus follicular unit extraction whether manual versus robotic, the role of platelet-rich plasma and low-level light surgery in hair transplant surgery. Hair transplant surgery creates consistently natural appearing hair. As with all techniques, there are controversies regarding the optimal method for performing the procedure. Some of the current controversies in hair transplant surgery include optimal donor harvesting techniques, elliptical donor harvesting versus follicular unit extraction, the role of low-level light therapy and the platelet-rich plasma therapy in the procedure. Future studies will further clarify their role in the procedure.

Intranasal desmopressin versus blood transfusion in cirrhotic patients with coagulopathy undergoing dental extraction: a randomized controlled trial.

PubMed

Stanca, Carmen M; Montazem, Andre H; Lawal, Adeyemi; Zhang, Jin X; Schiano, Thomas D

2010-01-01

Cirrhotic patients waiting for liver transplantation who need dental extractions are given fresh frozen plasma and/or platelets to correct coagulopathy. This is costly and may be associated with transfusion reactions and fluid overload. We evaluated the efficacy of intranasal desmopressin as an alternative to transfusion to correct the coagulopathy of cirrhotic patients undergoing dental extraction. Cirrhotic patients with platelet counts of 30,000 to 50,000/microL and/or international normalized ratio (INR) 2.0 to 3.0 were enrolled in a prospective, controlled, randomized clinical trial. Blood transfusion (fresh frozen plasma 10 mL/kg and/or 1 unit of single donor platelets, respectively) or intranasal desmopressin (300 microg) were given before dental extraction. A standard oral and maxillofacial surgical treatment protocol was performed by the same surgeon. Patients were followed for postextraction bleeding and side-effects over the next 24 to 48 hours. No significant differences were noted between the 2 groups in gender, age, INR, platelet count, creatinine, total bilirubin, ALT, albumin, MELD score, or number of teeth removed (median 3 vs 4). The number of teeth removed ranged between 1 and 31 in the desmopressin group and 1 and 22 in the transfusion group. No patients in desmopressin group required rescue blood transfusion after extraction. One patient in the transfusion group had bleeding after the procedure and required an additional transfusion. Another patient experienced an allergic reaction at the end of transfusion, which was effectively treated with diphenhydramine. Treatment associated average costs were lower for desmopressin ($700/patient) compared with transfusion ($1,173/patient). Intranasal desmopressin was as effective as blood transfusion in achieving hemostasis in cirrhotic patients with moderate coagulopathy undergoing dental extraction. Intranasal desmopressin was much more convenient, less expensive, and well tolerated.

Sports medicine and platelet-rich plasma: nonsurgical therapy.

PubMed

Grambart, Sean T

2015-01-01

A Cochrane Review was performed to assess the effects of platelet-rich therapies for treating musculoskeletal soft tissue injuries. Selection criteria were randomized and quasirandomized controlled trials (RCTs) that compared platelet-rich therapy with either placebo, autologous whole blood, dry needling, or no platelet-rich therapy for people with acute or chronic musculoskeletal soft tissue injuries. Primary outcomes were functional status, pain, and adverse effects. The investigators found 19 studies that compared platelet-rich therapy with placebo, autologous whole blood, dry needling, or no platelet-rich therapy. Disorders included rotator cuff tears (arthroscopic repair; 6 trials); shoulder impingement syndrome surgery (1 trial); elbow epicondylitis (3 trials); anterior cruciate ligament (ACL) reconstruction (4 trials), ACL reconstruction (donor graft site application; 2 trials), patellar tendinopathy (1 trial), Achilles tendinopathy (1 trial), and acute Achilles rupture surgical repair (1 trial). They further subdivided the studies based on type of treatment, including tendinopathies in which platelet-rich therapy injections were the main treatment (5 trials), and surgical augmentation procedures in which platelet-rich therapy was applied during surgery (14 trials). The conclusion was that there is currently insufficient evidence to support the use of platelet-rich therapy for treating musculoskeletal soft tissue injuries. Researchers contemplating RCTs should consider the coverage of currently ongoing trials when assessing the need for future RCTs on specific conditions. There is a need for standardization of PRP preparation methods. At this time, the use of PRP in foot and ankle surgery as an orthobiologic does not have an absolute indication. Many of the studies are lower evidence-based from surgical techniques. Several in vitro studies have shown that growth factors promote the regeneration of bone, cartilage, and tendons. More clinical studies are needed to evaluate the use of PRP as an orthobiologic. In the author’s opinion, PRP does have a role when conservative treatment has failed and the next treatment option is an invasive surgical procedure Copyright © 2015 Elsevier Inc. All rights reserved.

A novel second-generation polyolefin container for storage of single-donor apheresis platelets.

PubMed

Shimizu, T; Kouketsu, K; Kamiya, T; Futagawa, H; Hirose, S

1989-01-01

A non-blow-molded LE-2 polyolefin (PO) container was developed to store single-donor apheresis platelet concentrates (PCs) processed by the Haemonetics Plasma Collecting System (PCS) at 22 degrees C for over 1 day. We molded PO containers with heat-sealing of light-weight polymer alloy films with a thickness of 0.25 mm. The film was made of polymer blends consisting of polypropylene, styrene ethylene butylene styrene-block copolymer, and ethylene ethylacrylate copolymer. The PO container with enough strength and flexibility in routine practice has 2 and 1.6 times higher oxygen and carbon dioxide gas transfer properties than standard polyvinyl chloride (PVC) plastic containers. PCs (1-1.9 x 10(11) platelets) processed from 450 ml platelet-rich plasma were stored in 0.6-liter PO containers at 22 degrees C with flatbed agitation for up to 6 days. The pH of PCs was well maintained at the mean values of 7.0 in PO containers after 6 days in the well-oxygenated condition. The energy metabolism of stored platelets was determined. Oxygen consumption rates of platelets stored in PO containers averaged 1.5 nmol/min/10(9) platelets. The rates of glucose consumption and lactate production were 0.4 and 0.8 nmol/min/10(11) platelets, respectively. The rates of adenosine triphosphate (ATP) generation of platelets, 9.7 nmol/min/10(9) platelets, in PO containers did not differ from those in the PVC containers. Aggregation responses to adenosine diphosphate and hypotonic shock response of platelets were better maintained in PO containers. The morphological changes into sphere forms with projections and the appearance of unclassified forms were more frequently observed in PO than in PVC containers.(ABSTRACT TRUNCATED AT 250 WORDS)

Microparticles variability in fresh frozen plasma: preparation protocol and storage time effects

PubMed Central

Kriebardis, Anastasios G.; Antonelou, Marianna H.; Georgatzakou, Hara T.; Tzounakas, Vassilis L.; Stamoulis, Konstantinos E.; Papassideri, Issidora S.

2016-01-01

Background Extracellular vesicles or microparticles exhibiting procoagulant and thrombogenic activity may contribute to the haemostatic potential of fresh frozen plasma. Materials and methods Fresh frozen plasma was prepared from platelet-rich plasma at 20 °C (Group-1 donors) or directly from whole blood at 4 °C (Group-2 donors). Each unit was aseptically divided into three parts, stored frozen for specific periods of time, and analysed by flow cytometry for procoagulant activity immediately after thaw or following post-thaw storage for 24 h at 4 °C. Donors’ haematologic, biochemical and life-style profiles as well as circulating microparticles were analysed in parallel. Results Circulating microparticles exhibited a considerable interdonor but not intergroup variation. Fresh frozen plasma units were enriched in microparticles compared to plasma in vivo. Duration of storage significantly affected platelet- and red cell-derived microparticles. Fresh frozen plasma prepared directly from whole blood contained more residual platelets and more platelet-derived microparticles compared to fresh frozen plasma prepared from platelet-rich plasma. Consequently, there was a statistically significant difference in total, platelet- and red cell-derived microparticles between the two preparation protocols over storage time in the freezer. Preservation of the thawed units for 24 h at 4 °C did not significantly alter microparticle accumulation. Microparticle accumulation and anti-oxidant capacity of fresh frozen plasma was positively or negatively correlated, respectively, with the level of circulating microparticles in individual donors. Discussion The preparation protocol and the duration of storage in the freezer, independently and in combination, influenced the accumulation of microparticles in fresh frozen plasma units. In contrast, storage of thawed units for 24 h at 4 °C had no significant effect on the concentration of microparticles. PMID:27136430

Blood platelets: computerized morphometry applied on optical images

NASA Astrophysics Data System (ADS)

Korobova, Farida V.; Ivanova, Tatyana V.; Gusev, Alexander A.; Shmarov, Dmitry A.; Kozinets, Gennady I.

2000-11-01

The new technology of computerized morphometric image analysis of platelets on blood smears was developed. In a basis of the device is included analysis of cytophotometric and morphometric parameters of platelets. Geometrical and optical parameters of platelets on 35 donors, platelet concentrates and 15 patients with haemorrhagic thrombocythaemia were investigated, average meanings for the area, diameter, its logarithms and optical density of platelets in norm were received. Distribution of the areas, diameters and optical densities of platelets of patients with haemorrhagic thrombocythaemia differed from those at the healthy people. After a course of treatment these meanings came nearer to normal. The important characteristics of platelets in platelet concentrates after three days of storage were in limits of normal meanings, but differed from those in whole blood platelets. Obtained data allow to enter the quantitative standards into investigation of platelets of the healthy people and at various alteration of thrombocytopoieses.

Impact of ABO-Identical vs ABO-Compatible Nonidentical Plasma Transfusion in Trauma Patients

DTIC Science & Technology

2010-09-01

and B patients in turn could receive AB donor plasma. Few studies have examined the im- pact of compatible nonidentical plasma transfusion . In platelet ... transfusion ,19 the administration of compatible nonidenti- cal platelets to patients undergoing coro- nary artery bypass grafting or valve re...significantly different (in boldface) and for the volume of packed red blood cells, plasma, platelets , cryoprecipitate, and factor VIIa transfused . cBecause

Frequent plateletpheresis does not clinically significantly decrease platelet counts in donors.

PubMed

Katz, Louis; Palmer, Kim; McDonnell, Emily; Kabat, Andy

2007-09-01

In October 2005, the US Food and Drug Administration (FDA) issued draft guidance on collecting platelets (PLTs) by automated methods. The FDA proposed limiting collections to 24 components, rather than 24 procedures, annually with up to 3 components per procedure. The rationale was from literature suggesting frequent PLT collection resulted in significant declines in donor PLT counts. Additional requirements for minimal interdonation intervals were proposed. Plateletpheresis records at a regional blood center with predonation PLT counts were used to assess the impact of the restriction on PLT collections. They were reviewed to demonstrate the effects of collection frequency, number of products collected, and interdonation interval on donor PLT counts. Total protein and albumin levels were compared in a subset of 24-times-per-year PLT donors and control whole-blood donors. A limit of 24 components would require replacement of approximately 20 percent of the donor base to recover lost components. No clinically important decrease in PLT counts before donation was seen in donors donating multiple PLT components up to 24 times per year, regardless of interdonation interval. No frequent donor was deferred for a PLT count less than 150 x 10(9) per L. Short interdonation intervals were associated with statistically but not clinically important decreases in PLT counts. Protein levels were not distinguishable between PLT donors and controls. The proposed restrictions are not required to prevent thrombocytopenia in frequent PLT donors and would adversely impact the supply of apheresis PLTs. Protein levels are maintained in these high-frequency donors.

High incidence of defective high-shear platelet function among platelet donors.

PubMed

Harrison, Paul; Segal, Helen; Furtado, Charlene; Verjee, Salim; Sukhu, Kampta; Murphy, Michael F

2004-05-01

Because single-donor plateletpheresis concentrates now account for a large percentage of PLT concentrates, the PLT quality of individual donations is increasingly important. There has been little previous work on PLT function in blood donors. The aim of this study was to investigate the prevalence of defective PLT function among 100 healthy UK PLT donors on 3 consecutive donation days. Citrated blood samples were taken before plateletpheresis. High-shear PLT function testing was performed by a PLT function analyzer (PFA-100, Dade Behring), within both collagen-ADP (CADP) and collagen-epinephrine (CEPI) cartridges. Sixteen percent of PLT donors (mainly over the 3 donating days) had prolonged CEPI closure times (CTs) only, indicative of an aspirin-like pattern; 9 percent had a severe defect with prolonged CEPI CTs between 200 and 300 seconds, and 4 percent had maximal CEPI CTs of greater than 300 seconds. The majority of prolonged CEPI CTs appeared transient in nature. PLT dysfunction as detected by the PFA-100 is surprisingly common within a voluntary PLT donor population. The majority of CEPI defects appeared transient in nature and are indicative of surreptitious intake of cyclooxygenase inhibitors (e.g., aspirin). Identification of defective PLT function within donors would provide a simple means to eradicate defective PLTs from being clinically utilized.

Point of care hemoglobin testing in plateletpheresis donors: Noninvasive versus invasive methods.

PubMed

Mallhi, R S; Pawar, Amit; Kushwaha, Neerja; Kumar, Sudeep; Dimri, Ujjwal

2016-10-01

Predonation hemoglobin (Hb) for plateletpheresis donors is estimated by presently available invasive methods. Venous samples of only those donors whose Hb is more than 12.5 g/dl are screened for complete blood count and transfusion transmissible infections. There is a pressing need to substitute this invasive Hb test with noninvasive one to reduce donor discomfort and avoid further pricking the donor. We therefore went ahead with the aim of comparing a noninvasive Hb estimation method NBM 200 with the invasive method - Hemocue, taking SYSMEX KX-21 as a gold standard. 500 voluntary consenting plateletpheresis donors qualifying the laid down criteria for platelet donation were included in the study. Hb readings obtained by the NBM 200 and Hemocue were compared to those obtained from the fully automated hematology analyzer SYSMEX KX-21. Coefficients of correlation were found to be statistically significant at <0.0001 level of confidence. Results of Friedman's test on the three methods also showed significant difference in means. Bland-Altman plots and mountain plots also confirm the same. NBM 200 was found to be more sensitive, specific, and precise than Hemocue in detecting ineligible donors. NBM 200 was found to be more sensitive, specific, and precise as compared to Hemocue for predonation screening of Hb in plateletpheresis donors and the prime benefit it offers is that it is 'noninvasive' thereby assisting in stemming the platelet donor pool. The onus lies on the blood transfusion services to make use of appropriately validated gadgets that reduce the donor discomfort.

Preoperative Thromboelastometry as a Predictor of Transfusion Requirements during Adult Living Donor Liver Transplantation.

PubMed

Fayed, Nirmeen; Mourad, Wessam; Yassen, Khaled; Görlinger, Klaus

2015-03-01

The ability to predict transfusion requirements may improve perioperative bleeding management as an integral part of a patient blood management program. Therefore, the aim of our study was to evaluate preoperative thromboelastometry as a predictor of transfusion requirements for adult living donor liver transplant recipients. The correlation between preoperative thromboelastometry variables in 100 adult living donor liver transplant recipients and intraoperative blood transfusion requirements was examined by univariate and multivariate linear regression analysis. Thresholds of thromboelastometric parameters for prediction of packed red blood cells (PRBCs), fresh frozen plasma (FFP), platelets, and cryoprecipitate transfusion requirements were determined with receiver operating characteristics analysis. The attending anesthetists were blinded to the preoperative thromboelastometric analysis. However, a thromboelastometry-guided transfusion algorithm with predefined trigger values was used intraoperatively. The transfusion triggers in this algorithm did not change during the study period. Univariate analysis confirmed significant correlations between PRBCs, FFP, platelets or cryoprecipitate transfusion requirements and most thromboelastometric variables. Backward stepwise logistic regression indicated that EXTEM coagulation time (CT), maximum clot firmness (MCF) and INTEM CT, clot formation time (CFT) and MCF are independent predictors for PRBC transfusion. EXTEM CT, CFT and FIBTEM MCF are independent predictors for FFP transfusion. Only EXTEM and INTEM MCF were independent predictors of platelet transfusion. EXTEM CFT and MCF, INTEM CT, CFT and MCF as well as FIBTEM MCF are independent predictors for cryoprecipitate transfusion. Thromboelastometry-based regression equation accounted for 63% of PRBC, 83% of FFP, 61% of cryoprecipitate, and 44% of platelet transfusion requirements. Preoperative thromboelastometric analysis is helpful to predict transfusion requirements in adult living donor liver transplant recipients. This may allow for better preparation and less cross-matching prior to surgery. The findings of our study need to be re-validated in a second prospective patient population.

Platelet Vascular Endothelial Growth Factor is a Potential Mediator of Transfusion-Related Acute Lung Injury.

PubMed

Maloney, James P; Ambruso, Daniel R; Voelkel, Norbert F; Silliman, Christopher C

The occurrence of non-hemolytic transfusion reactions is highest with platelet and plasma administration. Some of these reactions are characterized by endothelial leak, especially transfusion related acute lung injury (TRALI). Elevated concentrations of inflammatory mediators secreted by contaminating leukocytes during blood product storage may contribute to such reactions, but platelet-secreted mediators may also contribute. We hypothesized that platelet storage leads to accumulation of the endothelial permeability mediator vascular endothelial growth factor (VEGF), and that intravascular administration of exogenous VEGF leads to extensive binding to its lung receptors. Single donor, leukocyte-reduced apheresis platelet units were sampled over 5 days of storage. VEGF protein content of the centrifuged supernatant was determined by ELISA, and the potential contribution of VEGF from contaminating leukocytes was quantified. Isolated-perfused rat lungs were used to study the uptake of radiolabeled VEGF administered intravascularly, and the effect of unlabeled VEGF on lung leak. There was a time-dependent release of VEGF into the plasma fraction of the platelet concentrates (62 ± 9 pg/ml on day one, 149 ± 23 pg/ml on day 5; mean ± SEM, p<0.01, n=8) and a contribution by contaminating leukocytes was excluded. Exogenous 125I-VEGF bound avidly and specifically to the lung vasculature, and unlabeled VEGF in the lung perfusate caused vascular leak. Rising concentrations of VEGF occur during storage of single donor platelet concentrates due to platelet secretion or disintegration, but not due to leukocyte contamination. Exogenous VEGF at these concentrations rapidly binds to its receptors in the lung vessels. At higher VEGF concentrations, VEGF causes vascular leak in uninjured lungs. These data provide further evidence that VEGF may contribute to the increased lung permeability seen in TRALI associated with platelet products.

Cystamine immobilization on TiO 2 film surfaces and the influence on inhibition of collagen-induced platelet activation

NASA Astrophysics Data System (ADS)

Zhou, Yujuan; Weng, Yajun; Zhang, Liping; Jing, Fengjuan; Huang, Nan; Chen, Junying

2011-12-01

Poor haemocompatibility is a main issue of artificial cardiovascular materials in clinical application. Nitric oxide (NO), produced by vascular endothelial cells, is a well known inhibitor of platelet adhesion and activation. Thus, NO-releasing biomaterials are beneficial for improving haemocompatibility of blood-contacting biomedical devices. In this paper, a novel method was developed for enhancement of haemocompatibility by exploiting endogenous NO donors. TiO 2 films were firstly synthesized on Si (1 0 0) wafers via unbalanced magnetron sputtering technology, and then polydopamine was grafted on TiO 2 films and used as a linker for further immobilization of cystamine. The obtained surfaces were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis. NO generation is evaluated by saville-griess reagents, and it shows that cystamine immobilized samples are able to catalytically generate NO by decomposing endogenous S-nitrosothiols (RSNO). In vitro platelet adhesion results reveal that cystamine modified surfaces can inhibit collagen-induced platelet activation. ELISA analysis reveals that cGMP in platelets obviously increases on cystamine immobilized surface, which suggests the reducing of platelet activation is through NO/cGMP signal channel. It can be concluded that cystamine immobilized surface shows better blood compatibility by catalyzing NO release from the endogenous NO donor. It may be a promising method for improvement of haemocompatibility of blood-contacting implants.

Ability of anti-glycoprotein IIb/IIIa agents to dissolve platelet thrombi formed on a collagen surface under blood flow conditions.

PubMed

Goto, Shinya; Tamura, Noriko; Ishida, Hideyuki

2004-07-21

We examined the lytic effects of anti-glycoprotein (GP) IIb/IIIa agents on platelet thrombi formed on the collagen surface under blood flow conditions. Anti-GP IIb/IIIa agents may influence platelet thrombi already formed. Blood samples were anticoagulated either by the specific antithrombin Argatroban (100 microM) or by unfractionated heparin (0.1 U/ml). After platelet thrombi were formed on a collagen surface following 6-min perfusion of whole blood obtained from eight adult donors containing fluorescinated platelets at a wall shear rate of 1,500 s(-1), additional blood samples from the same donors either containing or not containing anti-GP IIb/IIIa agents (abciximab, eptifibatide, or tirofiban) were perfused on these thrombi. The three-dimensional structures of the platelet thrombi were continuously observed by laser confocal microscopy equipped with a piezo-electric motor control unit and recorded. The platelet thrombi started to dissolve after perfusion of blood containing the anti-GP IIb/IIIa agents, whereas their growth resumed after subsequent perfusion of control blood. Only a single layer of platelets having heights of 3 +/- 1 microm, 3 +/- 2 microm, and 3 +/- 1 microm, respectively, could be seen after 6-min perfusion of blood containing abciximab, eptifibatide, and tirofiban, whereas the initial height of the platelet thrombi of 8 +/- 2 microm increased to 11 +/- 4 microm after subsequent perfusion of control blood (n = 8). The volume of the platelet thrombi, which was 3,352 +/- 1,045 microm(3) before starting the second perfusion, was reduced to 778 +/- 102 microm(3), 812 +/- 122 microm(3), and 856 +/- 144 microm(3) after 6-min perfusion of blood containing abciximab, eptifibatide, and tirofiban, respectively. We have shown in this study that anti-GP IIb/IIIa agents possess the ability to dissolve platelet thrombi.

21 CFR 640.22 - Collection of source material.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Platelets § 640.22 Collection of source material. (a) Whole blood used as the source of Platelets shall be collected as prescribed in § 640.4. (b... uninterrupted venipuncture with minimal damage to, and minimal manipulation of, the donor's tissue. [40 FR 4304...

Transformation of ATLA-negative leukocytes by blood components from anti-ATLA-positive donors in vitro.

PubMed

Miyamoto, K; Tomita, N; Ishii, A; Nishizaki, T; Kitajima, K; Tanaka, T; Nakamura, T; Watanabe, S; Oda, T

1984-06-15

Anti-ATLA-positive blood components transformed healthy human leukocytes in vitro. Blood components examined were packed red cells, whole blood, platelet concentrate and fresh frozen plasma. Leukocytes present in anti-ATLA-positive blood components such as packed red cells, whole blood and platelet concentrate easily transformed anti-ATLA-negative leukocytes. Co-culture in fresh frozen plasma, however, did not transform recipient leukocytes, and leukocytes of anti-ATLA-positive recipients proved refractory to transformation. The transformed cells were morphologically lymphoid, grew in suspension, and possessed normal recipient karyotypes except in the case of three platelet concentrates. A high proportion of all the transformed populations formed E-rosettes with neuraminidase-treated sheep erythrocytes. The cytoplasm of over 90% of each recipient was stained brilliantly with antibodies against ATLV-determined antigens. Electron microscopy of these transformed cells revealed many C-type virus particles in the extracellular space. Blood components, such as packed red cells, whole blood and platelet concentrate, containing leukocytes from anti-ATLA-positive donors, should be used cautiously to prevent the transmission on ATLV to anti-ATLA-negative recipients.

Frequency and severity of transfusion-related acute lung injury--German haemovigilance data (2006-2007).

PubMed

Keller-Stanislawski, B; Reil, A; Günay, S; Funk, M B

2010-01-01

In an observational cohort study (2006-2007) the Paul-Ehrlich-Institut collected epidemiological data to investigate the frequency and causes of TRALI. Diagnosis of TRALI was confirmed according to criteria of the European Haemovigilance Network. Subsequent testing of white blood cell antibodies (WBC-Ab) against HLA or human neutrophil alloantigens was performed. Of a total of 187 reported TRALI cases, 44 could be confirmed consisting of 35 cases of antibody-mediated TRALI and nine cases of non-immune-mediated TRALI. Eight of 44 affected patients (18%) had a fatal outcome, seven cases with WBC-Ab positive plasma donors and one case with red blood cell donors. WBC antibodies were found in one male and 39 female donors. In 34 female donors, a history of pregnancy was confirmed. WBC-Ab positive donors presented four HLA class I antibodies, 15 HLA class II antibodies, 13 HLA class I and class II antibodies, one HNA-2a, and seven HNA-3a antibodies. WBC antibodies matching with recipient antigens were found exclusively in 28 female donors; 26 FFP donors, one platelet donor and one red blood cell donor. Reporting frequency of immune-mediated TRALI was 1:66,000 for fresh frozen plasma, 1:2.86 million for red blood cell concentrates and 1:420,000 for platelet concentrates. Reporting frequency of TRALI-related fatalities was 1:285,000 for FFP. Haemovigilance data show the significance of female donors with a history of pregnancy for the development of antibody-mediated TRALI. Manufacturing of FFP from male plasma and female donor screening for WBC-Ab could represent preventive measures.

[Demography and donation frequencies of blood and plasma donor populations in Germany].

PubMed

Ritter, Sabine; Willand, L; Reinhard, B; Offergeld, R; Hamouda, O

2008-08-01

According to Article 22 of the Transfusion Act, the Robert Koch Institute collects and evaluates nationwide data on the prevalence and incidence of transfusion-relevant infections among blood and plasma donors in Germany. Due to revision of the Transfusion Act in 2005 not only the number of donations but also the number of donors has become available for analysis. Here we give a detailed account on the demographic profile and donation frequencies of German whole blood, plasma and platelet donors in 2006. Overall, 4 % of the German population eligible to donate were active as repeat whole blood donors in 2006; 0.3 % repeatedly donated plasma or platelets. Irrespective of the type of donation, the percentage of donors among the general population was highest among the youngest age group (18 to 24 years). While the age distribution of whole blood repeat donors roughly resembled that of the general population, with the greatest number among those aged 35 to 44, younger age groups were overrepresented among repeat plasma donors. Donation frequency varied depending on donor age and sex, with an average of 1.9 per year for whole blood donations, 11.9 for plasmapheresis and 4.0 for plateletpheresis. With the exception of the latter, men donated more frequently than women. For both sexes, donation frequency increased with age. Detailed knowledge of the demographic profile and changes in the composition of donor populations are essential for planning adequate blood supply. The data presented may serve as reference for assessing the consequences of measures that affect the number of donors and/or donations (for example changing deferral criteria) in Germany.

The healthy donor profile of immunoregulatory soluble mediators is altered by stem cell mobilization and apheresis.

PubMed

Melve, Guro Kristin; Ersvaer, Elisabeth; Paulsen Rye, Kristin; Bushra Ahmed, Aymen; Kristoffersen, Einar K; Hervig, Tor; Reikvam, Håkon; Hatfield, Kimberley Joanne; Bruserud, Øystein

2018-05-01

Peripheral blood stem cells from healthy donors mobilized by granulocyte colony-stimulating factor (G-CSF) and thereafter harvested by leukapheresis are commonly used for allogeneic stem cell transplantation. Plasma levels of 38 soluble mediators (cytokines, soluble adhesion molecules, proteases, protease inhibitors) were analyzed in samples derived from healthy stem cell donors before G-CSF treatment and after 4 days, both immediately before and after leukapheresis. Donors could be classified into two main subsets based on their plasma mediator profile before G-CSF treatment. Seventeen of 36 detectable mediators were significantly altered by G-CSF; generally an increase in mediator levels was seen, including pro-inflammatory cytokines, soluble adhesion molecules and proteases. Several leukocyte- and platelet-released mediators were increased during apheresis. Both plasma and graft mediator profiles were thus altered and showed correlations to graft concentrations of leukocytes and platelets; these concentrations were influenced by the apheresis device used. Finally, the mediator profile of the allotransplant recipients was altered by graft infusion, and based on their day +1 post-transplantation plasma profile our recipients could be divided into two major subsets that differed in overall survival. G-CSF alters the short-term plasma mediator profile of healthy stem cell donors. These effects together with the leukocyte and platelet levels in the graft determine the mediator profile of the stem cell grafts. Graft infusion also alters the systemic mediator profile of the recipients, but further studies are required to clarify whether such graft-induced alterations have a prognostic impact. Copyright © 2018. Published by Elsevier Inc.

[Demography and donation frequencies of blood and plasma donor populations in Germany. Update 2010 and 5-year comparison].

PubMed

Ritter, S; Hamouda, O; Offergeld, R

2012-08-01

The Robert Koch Institute collects and evaluates nationwide data on the incidence and prevalence of transfusion-relevant infections among blood and plasma donors in Germany. Since 2006 data not only on the number of donations tested but also on the number of the respective donors have become available. The demographic profile and donation frequencies of German whole blood, plasma and platelet donors in 2010 and the percentages among the general population are described and compared to data from 2006. Although the general population eligible to donate blood is on the decline since 2003, with a loss of 2% between 2006 and 2010, this has not led to a decrease in the number of blood donors and donations. Instead, the number of new and repeat whole blood donors increased by 8% and 7%, respectively. At the same time, the number of new plasma donors grew by 23%, that of repeat plasma donors by 41%. In 2010 more than 4.3% of the population aged 18-68 years was active as repeat whole blood donors; 0.4% repeatedly donated plasma or platelets. Since 2006 the percentage of donors among the general population increased significantly, especially among the youngest age group (18-24 years). Donation frequency varied depending on donor age and sex, with an average of 1.9 per year for whole blood donations, 12.5 for plasmapheresis and 5.0 for plateletpheresis. While the donation frequency for whole blood remained unchanged since 2006, the frequency of apheresis donations increased, especially among older donors. By recruiting more new donors and retaining and reactivating existing ones more effectively, the number of whole blood and apheresis donations was augmented.

Human platelet lysate as a promising growth-stimulating additive for culturing of stem cells and other cell types.

PubMed

Shanskii, Ya D; Sergeeva, N S; Sviridova, I K; Kirakozov, M S; Kirsanova, V A; Akhmedova, S A; Antokhin, A I; Chissov, V I

2013-11-01

We compared the composition and biological activity of fetal calf serum and platelet lysate from donor platelet concentrate. In platelet lysate, the concentrations of alkaline phosphatase, lactate dehydrogenase, creatinine, and mineral metabolism parameters were lower, while parameters of lipid and protein metabolism were higher than in fetal calf serum. The concentrations of growth factors (platelet-derived (AA, AB, BB), vascular endothelial, insulin-like, and transforming growth factor β) in platelet lysate 1.7-148.7-fold surpassed the corresponding parameters in fetal calf serum. After replacement of fetal calf serum with platelet lysate in the culture medium (0, 25, 50, 75, and 100%), the count of multipotent mesenchymal stromal cells on day 7 (in comparison with day 1) increased by 154.8, 206.6, 228.2, 367.7, and 396.5%, respectively. Thus, platelet lysate can be an adequate non-xenogenic alternative for fetal calf serum.

Von Willebrand Factor Deposition and ADAMTS-13 Consumption in Allograft Tissue of Thrombotic Microangiopathy-like Disorder After Living Donor Liver Transplantation: A Case Report.

PubMed

Nakanuma, S; Miyashita, T; Hayashi, H; Ohbatake, Y; Takamura, H; Okazaki, M; Yamaguchi, T; Sakai, S; Makino, I; Oyama, K; Tajima, H; Ninomiya, I; Fushida, S; Ohta, T

2017-09-01

Thrombotic microangiopathy (TMA) pathogenesis after living donor liver transplantation (LDLT) is thought to be caused by release of unusually large von Willebrand factor multimers (UL-vWFMs) resulting from sinusoidal endothelial cell damage and induction of platelet adhesion and aggregation. A decrease in a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs-13 (ADAMTS-13) that cleave UL-vWFMs might cause excessive UL-vWFMs activity and result in platelet thrombus formation. However, this phenomenon has not undergone a full pathologic assessment. A 60-year-old man was diagnosed with hepatitis C-related end-stage cirrhosis. His son was the donor, and he underwent LDLT. On postoperative day 44, his laboratory findings met most TMA diagnostic criteria, and he was diagnosed with TMA-like disorder (TMALD). Localization of CD42b as a platelet marker, vWF, and ADAMTS-13 in allograft tissue of this patient were evaluated using immunohistochemistry. CD42b expression was observed as platelet aggregates attached to hepatocytes or within the hepatocyte cytoplasm, a morphology called extravasated platelet aggregation (EPA). vWF expression was observed mainly as deposited compact clusters, and ADAMTS-13 expression resembled distinct dots throughout the liver tissue. These findings suggest that EPA indicated sinusoidal endothelial cell damage followed by detachment, and vWF deposition resulted from UL-vWFM oversynthesis. ADAMTS-13 might be consumed in the allograft tissue to cleave UL-vWFMs, but ADAMTS-13 levels might be insufficient to cleave all the deposited UL-vWFMs. We present the case of an LDLT recipient diagnosed with TMALD using blood tests, which showed the presence of TMA pathogenesis in the allograft. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of Platelet-Rich Plasma and Indomethacin on Biomechanics of Rotator Cuff Repair.

PubMed

Meadows, Molly C; Levy, David M; Ferry, Christopher M; Gardner, Thomas R; Teratani, Takeshi; Ahmad, Christopher S

We conducted a study to determine if platelet-rich plasma (PRP) enhances the strength of rotator cuff repair (RCR) and if concomitant use of nonsteroidal anti-inflammatory drugs (NSAIDs) affects PRP efficacy. We also wanted to determine the optimal centrifugation protocol for making PRP from rats. This study used 48 rats, 14 in a centrifugation protocol and 34 in an operative protocol. Six syngeneic rats from the operative group were used as PRP blood donors; the other 28 operative rats underwent bilateral RCRs. The Autologous Conditioned Plasma system (Arthrex) was used to prepare leukocyte-poor PRP. One shoulder was randomized to an intratendinous PRP injection, and the other received normal saline. Each rat was also randomly placed on a postoperative diet, either a regular diet or an indomethacin-enhanced diet. After rats were euthanized at 3 weeks, specimens were dissected to isolate the supraspinatus tendon at its humeral attachment, which was subjected to biomechanical testing. PRP prepared with a protocol of 5 minutes × 1300 revolutions per minute had the highest platelet index. Mean (SD) energy to failure was significantly higher (P = .03) in tendons treated with PRP, 11.7 (7.3) N-mm, than in tendons treated with saline, 8.7 (4.6) N-mm. Both groups (PRP, saline) showed no significant differences between tendons treated with NSAIDs and those not treated with NSAIDs. Intraoperative application of PRP enhances energy to failure after RCR in rats. There were no differences in biomechanical strength with NSAID use and no interactions between PRP and NSAID use.

Platelet-rich plasma preparation for regenerative medicine: optimization and quantification of cytokines and growth factors.

PubMed

Amable, Paola Romina; Carias, Rosana Bizon Vieira; Teixeira, Marcus Vinicius Telles; da Cruz Pacheco, Italo; Corrêa do Amaral, Ronaldo José Farias; Granjeiro, José Mauro; Borojevic, Radovan

2013-06-07

Platelet-rich plasma (PRP) is nowadays widely applied in different clinical scenarios, such as orthopedics, ophthalmology and healing therapies, as a growth factor pool for improving tissue regeneration. Studies into its clinical efficiency are not conclusive and one of the main reasons for this is that different PRP preparations are used, eliciting different responses that cannot be compared. Platelet quantification and the growth factor content definition must be defined in order to understand molecular mechanisms behind PRP regenerative strength. Standardization of PRP preparations is thus urgently needed. PRP was prepared by centrifugation varying the relative centrifugal force, temperature, and time. Having quantified platelet recovery and yield, the two-step procedure that rendered the highest output was chosen and further analyzed. Cytokine content was determined in different fractions obtained throughout the whole centrifugation procedure. Our method showed reproducibility when applied to different blood donors. We recovered 46.9 to 69.5% of total initial platelets and the procedure resulted in a 5.4-fold to 7.3-fold increase in platelet concentration (1.4 × 10(6) to 1.9 × 10(6) platelets/μl). Platelets were highly purified, because only <0.3% from the initial red blood cells and leukocytes was present in the final PRP preparation. We also quantified growth factors, cytokines and chemokines secreted by the concentrated platelets after activation with calcium and calcium/thrombin. High concentrations of platelet-derived growth factor, endothelial growth factor and transforming growth factor (TGF) were secreted, together with the anti-inflammatory and proinflammatory cytokines interleukin (IL)-4, IL-8, IL-13, IL-17, tumor necrosis factor (TNF)-α and interferon (IFN)-α. No cytokines were secreted before platelet activation. TGF-β3 and IFNγ were not detected in any studied fraction. Clots obtained after platelet coagulation retained a high concentration of several growth factors, including platelet-derived growth factor and TGF. Our study resulted in a consistent PRP preparation method that yielded a cytokine and growth factor pool from different donors with high reproducibility. These findings support the use of PRP in therapies aiming for tissue regeneration, and its content characterization will allow us to understand and improve the clinical outcomes.

21 CFR 606.121 - Container label.

Code of Federal Regulations, 2012 CFR

2012-04-01

... the product. (i) A paid donor is a person who receives monetary payment for a blood donation. (ii) A volunteer donor is a person who does not receive monetary payment for a blood donation. (iii) Benefits, such... this paragraph. (6) For Whole Blood, Plasma, Platelets, and partial units of Red Blood Cells, the...

Mesenchymal Stem Cells Suppress Chronic Rejection in Heterotopic Small Intestine Transplant Rat Models Via Inhibition of CD68, Transforming Growth Factor- β1, and Platelet-Derived Growth Factor Expression.

PubMed

Li, Fuxin; Cao, Jisen; Zhao, Zhicheng; Li, Chuan; Qi, Feng; Liu, Tong

2017-04-01

Mesenchymal stem cells are easy to obtain and expand, with characteristics of low immunogenicity and strong tissue repair capacity. In this study, our aim was to investigate the role of mesenchymal stem cells in chronic immune rejection of heterotopic small intestine transplant in rats. After successfully constructing a rat chronic immune rejection model of heterotopic small intestine transplant, we infused mesenchymal stem cells into the animal recipients. We observed mesenchymal stem cell location in the recipients, recipient survival, pathology changes, and the expression of CD68, transforming growth factor β1, and platelet-derived growth factor C in the donor intestine. Mesenchymal stem cells inhibited the lymphocyte proliferation caused by concanavalin A in vitro. After stem cells were infused into recipients, they were mainly located in the donor intestine, as well as in the spleen and thymus. Recovery after transplant and pathology changes of the donor intestine in rats with stem cell infusion were better than in the control group; however, we observed no differences in survival time, accompanied by downregulated expression of CD68, transforming growth factor β1, and platelet-derived growth factor C. Mesenchymal stem cells, to a certain extent, could inhibit the process of chronic rejection. The mechanisms may include the inhibited function of these cells on lymphocyte proliferation, reduced infiltration of macrophages, and reduced expression of transforming growth factor β1 and platelet-derived growth factor C.

Platelet bioreactor-on-a-chip

PubMed Central

Mazutis, Linas; Wu, Stephen; Sylman, Joanna L.; Ehrlicher, Allen; Machlus, Kellie R.; Feng, Qiang; Lu, Shijiang; Lanza, Robert; Neeves, Keith B.; Weitz, David A.; Italiano, Joseph E.

2014-01-01

Platelet transfusions total >2.17 million apheresis-equivalent units per year in the United States and are derived entirely from human donors, despite clinically significant immunogenicity, associated risk of sepsis, and inventory shortages due to high demand and 5-day shelf life. To take advantage of known physiological drivers of thrombopoiesis, we have developed a microfluidic human platelet bioreactor that recapitulates bone marrow stiffness, extracellular matrix composition, micro-channel size, hemodynamic vascular shear stress, and endothelial cell contacts, and it supports high-resolution live-cell microscopy and quantification of platelet production. Physiological shear stresses triggered proplatelet initiation, reproduced ex vivo bone marrow proplatelet production, and generated functional platelets. Modeling human bone marrow composition and hemodynamics in vitro obviates risks associated with platelet procurement and storage to help meet growing transfusion needs. PMID:25606631

Clinical Observation of Factors in the Efficacy of Blood Component Transfusion in Patients following Hematopoietic Stem Cell Transplantation

PubMed Central

Zhang, Xi; Xiao, Yanni; Ran, Qian; Liu, Yao; Duan, Qianbi; Duan, Huiling; Ye, Xingde; Li, Zhongjun

2012-01-01

Background Factors affecting the efficacy of platelet and red blood cell (RBC) transfusion in patients undergoing hematopoietic stem cell transplantation (HSCT) have not been studied extensively. We aimed to evaluate platelet and RBC transfusion efficacy by measuring the platelet corrected count increment and the hemoglobin increment, respectively, 24 h after transfusion in 105 patients who received HSCT. Methodology/Principal Findings Using retrospective analysis, we studied whether factors, including gender, time of transplantation, the compatibility of ABO group between HSC donors and recipients, and autologous or allogenic transplantation, influence the efficacy of blood component transfusion. We found that the infection rate of HSCT patients positively correlated with the transfusion amount, and the length of stay in the laminar flow room was associated with transfusion. We found that platelet transfusion performed during HSCT showed significantly better efficacy than that performed before HSCT. The effect of platelet transfusion in auto-transplantation was significantly better than that in allo-transplantation. The efficacy of RBC transfusion during HSCT was significantly lower than that performed before HSCT. The efficacy of RBC transfusion in auto-transplantation was significantly higher than that in allo-transplantation. Allo-transplantation patients who received HSCs from compatible ABO groups showed significantly higher efficacy during both platelet and RBC transfusion. Conclusions We conclude that the efficacy of platelet and RBC transfusions does not correlate with the gender of patients, while it significantly correlates with the time of transplantation, type of transplantation, and ABO compatibility between HSC donors and recipients. During HSCT, the infection rate of patients positively correlates with the transfusion amount of RBCs and platelets. The total volume of RBC units transfused positively correlates with the length of the patients’ stay in the laminar flow room. PMID:22701516

Flow Cytometric Panel-Reactive Antibody Results and the Ability to Find Transfusion-Compatible Platelets after Antibody-Desensitization for Allogeneic Bone Marrow Transplant.

PubMed

Rosenbaum, Eric R; Pandey, Soumya; Harville, Terry O; Drobena, Gina A; Cottler-Fox, Michele

2016-12-01

Panel reactive antibody (PRA) reduction protocols are used to decrease anti-HLA antibodies with concomitant PRA monitoring as a measure of successful treatment prior to organ and haploidentical blood and marrow transplant (BMT). We hypothesized that the more sensitive flow cytometry (FC) based assays for PRA [FlowPRA ® and Luminex ® based Single Antigen Bead (SAB)] would also correlate with the ability to find compatible platelets for allosensitized recipients. A female patient with myelodysplastic syndrome and a high HLA class I PRA [>90% PRA and cPRA by complement-dependent cytotoxicity (CDC) assay and Flow PRA] required allogeneic BMT. Baseline HLA Class I and class II antigen typing was performed and a matched sibling donor was identified. Although baseline anti-HLA class I and class II antibodies measured by FC and CDC revealed no donor specific antibodies (DSA), the decision was made to attempt antibody desensitization to facilitate platelet transfusion during BMT. FC and CDC assays were performed to determine anti-HLA class I antibodies and cPRA/%PRA prior to starting desensitization and at the end of desensitization. Over the course of desensitization and BMT, a total of 194 apheresis platelet units underwent cross-match (XM) using Capture-P ® . We compared temporally-related PRA results with platelet XM results. High PRA by FC or CDC assays correlates with a high % of XM-positive (incompatible) platelet units. When the CDC PRA fell to 2% after desensitization, platelet XM incompatibility fell from 100% to 63% positive (incompatible). When the FC PRA fell to 5% the positive platelet XM fell to 5%. Antibody desensitization facilitated platelet transfusion. PRA determination by FC appeared better correlated than determination by CDC with the ability to find XM-compatible platelets. © 2016 by the Association of Clinical Scientists, Inc.

Platelet factor 4/heparin antibodies in blood bank donors.

PubMed

Hursting, Marcie J; Pai, Poulomi J; McCracken, Julianna E; Hwang, Fred; Suvarna, Shayela; Lokhnygina, Yuliya; Bandarenko, Nicholas; Arepally, Gowthami M

2010-11-01

Platelet factor 4 (PF4)/heparin antibody, typically associated with heparin therapy, is reported in some heparin-naive people. Seroprevalence in the general population, however, remains unclear. We prospectively evaluated PF4/heparin antibody in approximately 4,000 blood bank donors using a commercial enzyme-linked immunosorbent assay for initial and then repeated (confirmatory) testing. Antibody was detected initially in 249 (6.6%; 95% confidence interval [CI], 5.8%-7.4%) of 3,795 donors and repeatedly in 163 (4.3%; 95% CI, 3.7%-5.0%) of 3,789 evaluable donors. "Unconfirmed" positives were mostly (93%) low positives (optical density [OD] = 0.40-0.59). Of 163 repeatedly positive samples, 116 (71.2%) were low positives, and 124 (76.1%) exhibited heparin-dependent binding. Predominant isotypes of intermediate to high seropositive samples (OD >0.6) were IgG (20/39 [51%]), IgM (9/39 [23%]), and indeterminate (10/39 [26%]). The marked background seroprevalence of PF4/heparin antibody (4.3%-6.6%) with the preponderance of low (and frequently nonreproducible) positives in blood donors suggests the need for further assay calibration, categorization of antibody level, and studies evaluating clinical relevance of "naturally occurring" PF4/heparin antibodies.

Comparison of postoperative coagulation profiles and outcome for sugammadex versus pyridostigmine in 992 living donors after living-donor hepatectomy

PubMed Central

Moon, Young-Jin; Kim, Sung-Hoon; Kim, Jae-Won; Lee, Yoon-Kyung; Jun, In-Gu; Hwang, Gyu-Sam

2018-01-01

Abstract Donor safety is the major concern in living donor liver transplantation, although hepatic resection may be associated with postoperative coagulopathy. Recently, the use of sugammadex has been gradually increased, but sugammadex is known to prolong prothrombin time (PT) and activated partial thromboplastin time (aPTT). We compared the postoperative coagulation profiles and outcomes of sugammadex versus pyridostigmine group in donors receiving living donor hepatectomy. Consecutive donor hepatectomy performed between September 2013 and August 2016 was retrospectively analyzed. For reversal of rocuronium-induced neuromuscular blockade, donors received sugammadex 4 mg/kg or pyridostigmine 0.25 mg/kg. The primary end-points were laboratory findings (PT, aPTT, hemoglobin, platelet count) and clinically evaluated postoperative bleeding (relaparotomy for bleeding, cumulative volume collected in drains). Secondary outcomes were anesthesia time, postoperative hospital day. Of 992 donors, 383 treated with sugammadex and 609 treated with pyridostigmine for the reversal of neuromuscular blockade. There were no significant differences between both groups for drop in hemoglobin and platelet, prolongation in PT, aPTT, and the amount of 24-h drain volume. Bleeding events within 24 h were reported in 2 (0.3%) for pyridostigmine group and 0 (0%) for sugammadex group (P = .262). Anesthesia time was significantly longer in pyridostigmine group than that in sugammadex group (438.8 ± 71.4 vs. 421.3 ± 62.3, P < .001). Postoperative hospital stay was significantly longer in pyridostigmine group than that in sugammadex group (P = .002). Sugammadex 4 mg/kg was not associated with increased bleeding tendency, but associated with reduced anesthesia time and hospital stay. Therefore, sugammadex may be safely used and will decrease morbidity in donor undergoing living-donor hepatectomy. PMID:29538210

Comparison of postoperative coagulation profiles and outcome for sugammadex versus pyridostigmine in 992 living donors after living-donor hepatectomy.

PubMed

Moon, Young-Jin; Kim, Sung-Hoon; Kim, Jae-Won; Lee, Yoon-Kyung; Jun, In-Gu; Hwang, Gyu-Sam

2018-03-01

Donor safety is the major concern in living donor liver transplantation, although hepatic resection may be associated with postoperative coagulopathy. Recently, the use of sugammadex has been gradually increased, but sugammadex is known to prolong prothrombin time (PT) and activated partial thromboplastin time (aPTT). We compared the postoperative coagulation profiles and outcomes of sugammadex versus pyridostigmine group in donors receiving living donor hepatectomy.Consecutive donor hepatectomy performed between September 2013 and August 2016 was retrospectively analyzed. For reversal of rocuronium-induced neuromuscular blockade, donors received sugammadex 4 mg/kg or pyridostigmine 0.25 mg/kg. The primary end-points were laboratory findings (PT, aPTT, hemoglobin, platelet count) and clinically evaluated postoperative bleeding (relaparotomy for bleeding, cumulative volume collected in drains). Secondary outcomes were anesthesia time, postoperative hospital day.Of 992 donors, 383 treated with sugammadex and 609 treated with pyridostigmine for the reversal of neuromuscular blockade. There were no significant differences between both groups for drop in hemoglobin and platelet, prolongation in PT, aPTT, and the amount of 24-h drain volume. Bleeding events within 24 h were reported in 2 (0.3%) for pyridostigmine group and 0 (0%) for sugammadex group (P = .262). Anesthesia time was significantly longer in pyridostigmine group than that in sugammadex group (438.8 ± 71.4 vs. 421.3 ± 62.3, P < .001). Postoperative hospital stay was significantly longer in pyridostigmine group than that in sugammadex group (P = .002).Sugammadex 4 mg/kg was not associated with increased bleeding tendency, but associated with reduced anesthesia time and hospital stay. Therefore, sugammadex may be safely used and will decrease morbidity in donor undergoing living-donor hepatectomy.

Donor Safety in Living Donor Liver Transplantation: A Single-Center Analysis of 300 Cases

PubMed Central

Lei, Jianyong; Yan, Lunan; Wang, Wentao

2013-01-01

Aim To evaluate the safety to donors of living-donor liver transplantation. Methods This study included 300 consecutive living liver tissue donors who underwent operations at our center from July 2002 to December 2012. We evaluated the safety of donors with regard to three aspects complications were recorded prospectively and stratified by grade according to Clavien’s classification, and the data were compared in two stages (the first 5 years’ experience (pre-January 2008) and the latter 5 years’ experience (post-January 2008); laboratory tests such as liver function and blood biochemistry were performed; and the health-related quality of life was evaluated. Results There was no donor mortality at our center, and the overall morbidity rate was 25.3%. Most of the complications of living donors were either grade I or II. There were significantly fewer complications in the latter period of our study than in the initial period (19.9% vs 32.6%, P<0.001), and biliary complications were the most common complications, with an incidence of 9%. All of the liver dysfunction was temporary; however, the post-operative suppression of platelet count lasted for years. Although within the normal range, eight years after operation, 22 donors showed lower platelet levels (189×109/L) compared with the pre-operative levels (267×109/L) (P<0.05). A total of 98.4% of donors had returned to their previous levels of social activity and work, and 99.2% of donors would donate again if it was required and feasible. With the exception of two donors who experienced grade III complications (whose recipients died) and a few cases of abdominal discomfort, fatigue, chronic pain and scar itching, none of the living donors were affected by physical problems. Conclusion With careful donor selection and specialized patient care, low morbidity rates and satisfactory long-term recovery can be achieved after hepatectomy for living-donor liver transplantation. PMID:23637904

Donor safety in living donor liver transplantation: a single-center analysis of 300 cases.

PubMed

Lei, Jianyong; Yan, Lunan; Wang, Wentao

2013-01-01

To evaluate the safety to donors of living-donor liver transplantation. This study included 300 consecutive living liver tissue donors who underwent operations at our center from July 2002 to December 2012. We evaluated the safety of donors with regard to three aspects complications were recorded prospectively and stratified by grade according to Clavien's classification, and the data were compared in two stages (the first 5 years' experience (pre-January 2008) and the latter 5 years' experience (post-January 2008); laboratory tests such as liver function and blood biochemistry were performed; and the health-related quality of life was evaluated. There was no donor mortality at our center, and the overall morbidity rate was 25.3%. Most of the complications of living donors were either grade I or II. There were significantly fewer complications in the latter period of our study than in the initial period (19.9% vs 32.6%, P<0.001), and biliary complications were the most common complications, with an incidence of 9%. All of the liver dysfunction was temporary; however, the post-operative suppression of platelet count lasted for years. Although within the normal range, eight years after operation, 22 donors showed lower platelet levels (189 × 10(9)/L) compared with the pre-operative levels (267 × 10(9)/L) (P<0.05). A total of 98.4% of donors had returned to their previous levels of social activity and work, and 99.2% of donors would donate again if it was required and feasible. With the exception of two donors who experienced grade III complications (whose recipients died) and a few cases of abdominal discomfort, fatigue, chronic pain and scar itching, none of the living donors were affected by physical problems. With careful donor selection and specialized patient care, low morbidity rates and satisfactory long-term recovery can be achieved after hepatectomy for living-donor liver transplantation.

[Experimental research on the effects of different activators on the formation of platelet-rich gel and the release of bioactive substances in human platelet-rich plasma].

PubMed

Yang, Y; Zhang, W; Cheng, B

2017-01-20

Objective: To explore the effects of calcium gluconate and thrombin on the formation of platelet-rich gel (PRG) and the release of bioactive substances in human platelet-rich plasma (PRP) and the clinical significance. Methods: Six healthy blood donors who met the inclusion criteria were recruited in our unit from May to August in 2016. Platelet samples of each donor were collected for preparation of PRP. (1) PRP in the volume of 10 mL was collected from each donor and divided into thrombin activation group (TA, added with 0.5 mL thrombin solution in dose of 100 U/mL) and calcium gluconate activation group (CGA, added with 0.5 mL calcium gluconate solution in dose of 100 g/L) according to the random number table, with 5 mL PRP in each group. Then the PRP of the two groups was activated in water bath at 37 ℃ for 1 h. The formation time of PRG was recorded, and the formation situation of PRG was observed within 1 hour of activation. After being activated for 1 h, one part of PRG was collected to observe the distribution of fibrous protein with HE staining, and another part of PRG was collected to observe platelet ultrastructure under transmission electron microscope (TEM). After being activated for 1 h, the supernatant was collected to determine the content of transforming growth factor β(1, )platelet-derived growth factor BB (PDGF-BB), vascular endothelial growth factor, basic fibroblast growth factor (bFGF), epidermal growth factor, and insulin-like growth factorⅠby enzyme-linked immunosorbent assay. (2) Another 10 mL PRP from each donor was collected and grouped as above, and the platelet suspension was obtained after two times of centrifugation and resuspension with phosphate buffered saline, respectively. And then they were treated with corresponding activator for 1 h as that in experiment (1). Nanoparticle tracking analyzer was used to detect the concentrations of microvesicles with different diameters and total microvesicles derived from platelet. Data were processed with t test. Results: (1) The formation time of PRG in group TA was (228±40) s, and the PRG volume reached the maximum at this moment. The PRG volume shrunk to the minimum after 30 minutes of activation. The formation time of PRG in group CGA was (690±71) s, and the PRG volume reached the maximum at this moment. After 55 minutes of activation, the PRG volume shrunk to the minimum. The formation time of PRG in group TA was obviously shorter than that in group CGA ( t =15.17, P <0.01). (2) HE staining showed that after 1 hour of activation, the red-stained area of fibrous protein in PRG of group TA was large and densely distributed, while that of group CGA was small and loosely distributed. TEM revealed that after 1 hour of activation, the platelets in PRG of group TA were fragmented, while lysing platelet structure, lysing α granule structure, intact α granule structure, and intact dense body structure were observed in PRG of group CGA. (3) The content of PDGF-BB released by PRP in group TA was (7.4±0.8) ng/mL, which was obviously higher than that in group CGA [(4.9±0.5) ng/mL, t =5.41, P <0.01]. The content of bFGF released by PRP in group CGA was (960±151) pg/mL, which was significantly higher than that in group TA [(384±56) pg/mL, t =8.75, P <0.01]. The content of the other 4 growth factors released by PRP in the two groups was close (with t values from 0.11 to 1.97, P values above 0.05). (4) The concentrations of total microvesicles, microvesicles with diameter more than 100 nm, and exosomes with diameter less than or equal to 100 nm derived from platelet in group CGA were (165.8±15.1)×10(8)/mL, (142.4±12.3)×10(8)/mL, and (23.4±2.9)×10(8)/mL respectively, which were significantly higher than those in group TA [(24.7±4.6)×10(8)/mL, (22.6±4.0)×10(8)/mL, and (2.1±0.7)×10(8)/mL, with t values from 17.36 to 22.66, P values below 0.01]. Conclusions: Calcium gluconate can slowly activate PRP, resulting in slowly shrunk PRG with high content of bFGF and high concentration of microvesicles, which is suitable for repairing articular cavity and sinus tract wound. Thrombin can rapidly activate PRP, resulting in quickly shrunk PRG with high content of PDGF-BB and a certain concentration of microvesicles, which is suitable for repairing acute trauma.

Blood Mixing Upregulates Platelet Membrane-Bound CD40 Ligand Expression in vitro Independent of Abo Compatibility.

PubMed

Huang, Go-Shine; Hu, Mei-Hua; Lin, Tso-Chou; Lin, Yi-Chang; Tsai, Yi-Ting; Lin, Chih-Yuan; Ke, Hung-Yen; Zheng, Xu-Zhi; Tsai, Chien-Sung

2017-11-30

Platelets play a central role in the inflammation response via CD40 ligand (CD40L) expression, which may lead to transfusion reactions. The precise role of platelet CD40L-mediated inflammation in transfusion reactions is unclear. Therefore, we assessed the effects of in vitro blood mixing on platelet CD40L expression. In addition, we examined the effect of ABO compatibility on CD40L expression. Donor packed red blood cells were acquired from a blood bank, and recipient blood was obtained from patients undergoing cardiac surgery and prepared as washed platelets. Donor blood was mixed with suspended, washed recipient platelets to obtain a final mixing ratio of 1%, 5%, or 10% (vol/vol). The blood mixtures were divided into three groups: Group M, cross-matched blood-type mixing (n = 20); Group S, ABO type-specific uncross-matched blood (n = 20); and Group I, ABO incompatibility (not ABO type-specific blood and not process cross-matched) mixing (n = 20). The blood mixtures were used to detect platelet membrane-bound CD40L expression by flow cytometry. Blood mixing resulted in an increase in CD40L expression in Group M (P < 0.001), Group S (P < 0.001), and Group I (P < 0.001). CD40L expression following blood mixing potentially led to a transfusion reaction in each of the groups. There were no differences in CD40L expression among the three groups (P = 0.988) correlated with ABO compatibility or incompatibility. This indicates that the reactions between red blood cell surface antigens and plasma antibodies do not play a role in the induction of CD40L expression.

The origin and function of platelet glycosyltransferases

PubMed Central

Rumjantseva, Viktoria; Sørensen, Anne Louise Tølbøll; Patel-Hett, Sunita; Josefsson, Emma C.; Bennett, Eric P.; Italiano, Joseph E.; Clausen, Henrik; Hartwig, John H.; Hoffmeister, Karin M.

2012-01-01

Platelets are megakaryocyte subfragments that participate in hemostatic and host defense reactions and deliver pro- and antiangiogenic factors throughout the vascular system. Although they are anucleated cells that lack a complex secretory apparatus with distinct Golgi/endoplasmic reticulum compartments, past studies have shown that platelets have glycosyltransferase activities. In the present study, we show that members of 3 distinct glycosyltransferase families are found within and on the surface of platelets. Immunocytology and flow cytometry results indicated that megakaryocytes package these Golgi-derived glycosyltransferases into vesicles that are sent via proplatelets to nascent platelets, where they accumulate. These glycosyltransferases are active, and intact platelets glycosylate large exogenous substrates. Furthermore, we show that activation of platelets results in the release of soluble glycosyltransferase activities and that platelets contain sufficient levels of sugar nucleotides for detection of glycosylation of exogenously added substrates. Therefore, the results of the present study show that blood platelets are a rich source of both glycosyltransferases and donor sugar substrates that can be released to function in the extracellular space. This platelet-glycosylation machinery offers a pathway to a simple glycoengineering strategy improving storage of platelets and may serve hitherto unknown biologic functions. PMID:22613794

Changes in pre- and post-donation platelet function in plateletpheresis donors.

PubMed

Zhou, Q; Yu, X; Cai, Y; Liu, L

2017-11-01

This study aimed to investigate the changes of platelet (PLT) function and coagulation time before and after plateletpheresis donation. The healthy donors were divided into four groups according to the annual number of plateletpheresis donation: 20 times group, 15 times group, 10 times group and 5 times group. The healthy non-blood donors were selected as controls. The donation interval was 14 days. The blood samples were collected before plateletpheresis donation and after 30min, 7 d, and 14 d of donation for determination of coagulation time, PLT function, plasma protein, serum iron and blood routine change. After 30min of plateletpheresis donation, the PLT function decreased and the coagulation time was prolonged. However, PLT function recovered to the pre-collection after 7 d of plateletpheresis donation and coagulation time recovered to the pre-collection after 14 d of plateletpheresis donation. Additionally, there was no difference regarding blood coagulation time and PLT function among blood donors and controls. The plasma protein and serum iron levels in 20 times and 15 times groups were within the normal reference range. The frequency of plateletpheresis donation will not affect PLT function, coagulation time, plasma protein and serum iron in donors. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Platelet function in whole-blood donors is impaired: the effects of painkillers.

PubMed

Curvers, Joyce; Dielis, Arne W J H; Heeremans, Judith; van Wersch, Jan W J

2007-01-01

Aspirin (ASA) or non-aspirin-like nonsteroidal anti-inflammatory drugs (NSAIDs) influence platelet (PLT) function by inhibiting cyclooxygenase enzymes. In this study, the aim was to address the use of ASA or NSAIDs before donation and the effect on PLT function. Donors were asked questions about recent use of ASA or NSAIDs. Furthermore, PLT function was evaluated by measurement of the closure time (CT) in a PLT function analyzer (PFA-100, Dade Behring) and by aggregometry (response to ADP or arachidonic acid [AA]). Of 100 questioned donors, 22 percent had used ASA (n = 4), NSAIDs (n = 6), or paracetamol (n = 12) before donation. Upon assessment of the PLT function in the PFA-100, 27 donors showed values of greater than 180 seconds, indicative of impaired PLT function. Of these, only 7 had used pain killers before donation. Furthermore, 15 of 22 users had normal CTs. Aggregation after stimulation with AA was absent in 33 PLT-rich samples. Again only 8 had reported use of ASA (3), NSAIDs (1), or paracetamol (4). Of the 22 users, 14 had normal AA aggregation responses. All donor samples showed ADP-induced aggregation, indicating PLT integrity. There was no difference between the group of donors who reported the intake of ASA or NSAIDs and the group of donors who did not with respect to the tested PLT function assays. It is concluded that there is a considerable group of donors that use PLT-influencing medication before donation. A relation between the reported use and impaired PLT function in blood donors could not be established, however. Impaired PLT function as tested may have other causes than intake of ASA or NSAIDs.

Dangerous universal donors: the reality of the Hemocentro in Belo Horizonte, Minas Gerais.

PubMed

Godin, Mariana Martins; Souza, Lucas de Oliveira; Schmidt, Luciana Cayres; Vieira, Lauro Mello; Diniz, Rejane Silva; Dusse, Luci Maria SantAna

2016-01-01

The term dangerous universal blood donor refers to potential agglutination of the erythrocytes of non-O recipients due to plasma of an O blood group donor, which contains high titers of anti-A and/or anti-B hemagglutinins. Thus, prior titration of anti-A and anti-B hemagglutinins is recommended to prevent transfusion reactions. The aim of this study was to estimate the frequency of dangerous universal donors in the blood bank of Belo Horizonte (Fundação Central de Imuno-Hematologia - Fundação Hemominas - Minas Gerais) by determining the titers of anti-A and anti-B hemagglutinins in O blood group donors. A total of 400 O blood group donors were randomly selected, from March 2014 to January 2015. The titers of anti-A and anti-B hemagglutinins (IgM and IgG classes) were obtained using the tube titration technique. Dangerous donors were those whose titers of anti-A or anti-B IgM were ≥128 and/or the titers of anti-A or anti-B IgG were ≥256. Donors were characterized according to gender, age and ethnicity. The hemagglutinins were characterized by specificity (anti-A and anti-B) and antibody class (IgG and IgM). Almost one-third (30.5%) of the O blood group donors were universal dangerous. The frequency among women was higher than that of men (p-value=0.019; odds ratio: 1.66; 95% confidence interval: 1.08-2.56) and among young donors (18-29 years old) it was higher than for donors between 49 and 59 years old (p-value=0.015; odds ratio: 3.05; 95% confidence interval: 1.22-7.69). There was no significant association between dangerous universal donors and ethnicity, agglutinin specificity or antibody class. Especially platelet concentrates obtained by apheresis (that contain a substantial volume of plasma), coming from dangerous universal donors should be transfused in isogroup recipients whenever possible in order to prevent the occurrence of transfusion reactions. Copyright © 2016 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.

Statins and nitric oxide donors affect thrombospondin 1-induced chemotaxis.

PubMed

Seymour, Keri; Stein, Jeffrey; Han, Xuan; Maier, Kristopher G; Gahtan, Vivian

2014-01-01

Thrombospondin 1 (TSP-1) induces vascular smooth muscle cell (VSMC) migration and intimal hyperplasia. Statins and nitric oxide (NO) donors decrease intimal hyperplasia. We previously showed that statins (long-term exposure) and NO donors inhibit TSP-1-induced VSMC chemotaxis. (1) Pretreatment with short-term statin will inhibit TSP-1-induced VSMC chemotaxis and (2) NO donors will enhance statin inhibition of TSP-1-induced or platelet-derived growth factor (PDGF)-induced VSMC chemotaxis. We examined these treatment effects on TSP-1-induced VSMC chemotaxis: (1) long-term (20 hours) versus short-term (20 minutes) pravastatin, (2) diethylenetriamine NONOate (DETA/NO) or S-nitroso-N-acetylpenicillamine (SNAP) in combination with pravastatin, and (3) comparison of TSP-1 to PDGF as a chemoattractant. Pravastatin (long term or short term) inhibited TSP-1-induced chemotaxis. Diethylenetriamine NONOate and SNAP impeded statin inhibition of TSP-1-induced chemotaxis. Platelet-derived growth factor and TSP-1 had opposite effects on DETA/NO-pravastatin treatment. Short-term statin pretreatment inhibited TSP-1-induced VSMC chemotaxis, suggesting a pleiotropic effect. High-dose NO reversed statin inhibition of TSP-1-induced chemotaxis, suggesting NO and statin combination therapies warrant further study. © The Author(s) 2014.

Analysis of rhG-CSF-effects on platelets by in vitro bleeding test and transcranial Doppler ultrasound examination.

PubMed

Söhngen, D; Wienen, S; Siebler, M; Boogen, C; Scheid, C; Schulz, A; Kobbe, G; Diehl, V; Heyll, A

1998-12-01

Experimental evidence suggests a stimulatory effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on both platelets and coagulation. RhG-CSF is increasingly used to stimulate healthy volunteer donors for blood stem cell mobilization. We therefore assessed 25 healthy donors receiving rhG-CSF for changes in in vitro bleeding test (IVBT), coagulation parameters and cerebral microembolism by transcranial Doppler (TCD) ultrasound. A significant shortening of IVBT was found on day 4 of rhG-CSF administration together with increased levels of fibrinogen and factor VIII and reduced activities of protein C and protein S. Although these changes are quite small it is possible that they may lead to a hypercoagulable state especially in donors with other risk factors for thromboembolism. However, TCD examination failed to detect any signs of microembolism. We therefore conclude that rhG-CSF leads to significant changes in coagulation parameters, but has no effect on TCD detectable microembolism as a stroke risk factor. However donors receiving rhG-CSF should be examined carefully to detect pre-existing changes in the coagulation system and we would like to suggest a routine thrombophilia screen.

Low Titer Group O Whole Blood in Emergency Situations

DTIC Science & Technology

2014-01-01

ABO incompatibility is defined as transfusion of donor anti-A and/or anti-B to a patient whose RBCs carry A or B antigens . Clinical consequences are...typically minor and frequently subclinical (12). Platelet transfusions with ABO- incompatible plasma occur routinely in hospitals in the United States...minor ABO incompatibility as nonidentical platelet transfusion . It is therefore a paradox that in some countries the regula- tory authorities have

Platelet Counts in Insoluble Platelet-Rich Fibrin Clots: A Direct Method for Accurate Determination.

PubMed

Kitamura, Yutaka; Watanabe, Taisuke; Nakamura, Masayuki; Isobe, Kazushige; Kawabata, Hideo; Uematsu, Kohya; Okuda, Kazuhiro; Nakata, Koh; Tanaka, Takaaki; Kawase, Tomoyuki

2018-01-01

Platelet-rich fibrin (PRF) clots have been used in regenerative dentistry most often, with the assumption that growth factor levels are concentrated in proportion to the platelet concentration. Platelet counts in PRF are generally determined indirectly by platelet counting in other liquid fractions. This study shows a method for direct estimation of platelet counts in PRF. To validate this method by determination of the recovery rate, whole-blood samples were obtained with an anticoagulant from healthy donors, and platelet-rich plasma (PRP) fractions were clotted with CaCl 2 by centrifugation and digested with tissue-plasminogen activator. Platelet counts were estimated before clotting and after digestion using an automatic hemocytometer. The method was then tested on PRF clots. The quality of platelets was examined by scanning electron microscopy and flow cytometry. In PRP-derived fibrin matrices, the recovery rate of platelets and white blood cells was 91.6 and 74.6%, respectively, after 24 h of digestion. In PRF clots associated with small and large red thrombi, platelet counts were 92.6 and 67.2% of the respective total platelet counts. These findings suggest that our direct method is sufficient for estimating the number of platelets trapped in an insoluble fibrin matrix and for determining that platelets are distributed in PRF clots and red thrombi roughly in proportion to their individual volumes. Therefore, we propose this direct digestion method for more accurate estimation of platelet counts in most types of platelet-enriched fibrin matrix.

Platelet Counts in Insoluble Platelet-Rich Fibrin Clots: A Direct Method for Accurate Determination

PubMed Central

Kitamura, Yutaka; Watanabe, Taisuke; Nakamura, Masayuki; Isobe, Kazushige; Kawabata, Hideo; Uematsu, Kohya; Okuda, Kazuhiro; Nakata, Koh; Tanaka, Takaaki; Kawase, Tomoyuki

2018-01-01

Platelet-rich fibrin (PRF) clots have been used in regenerative dentistry most often, with the assumption that growth factor levels are concentrated in proportion to the platelet concentration. Platelet counts in PRF are generally determined indirectly by platelet counting in other liquid fractions. This study shows a method for direct estimation of platelet counts in PRF. To validate this method by determination of the recovery rate, whole-blood samples were obtained with an anticoagulant from healthy donors, and platelet-rich plasma (PRP) fractions were clotted with CaCl2 by centrifugation and digested with tissue-plasminogen activator. Platelet counts were estimated before clotting and after digestion using an automatic hemocytometer. The method was then tested on PRF clots. The quality of platelets was examined by scanning electron microscopy and flow cytometry. In PRP-derived fibrin matrices, the recovery rate of platelets and white blood cells was 91.6 and 74.6%, respectively, after 24 h of digestion. In PRF clots associated with small and large red thrombi, platelet counts were 92.6 and 67.2% of the respective total platelet counts. These findings suggest that our direct method is sufficient for estimating the number of platelets trapped in an insoluble fibrin matrix and for determining that platelets are distributed in PRF clots and red thrombi roughly in proportion to their individual volumes. Therefore, we propose this direct digestion method for more accurate estimation of platelet counts in most types of platelet-enriched fibrin matrix. PMID:29450197

An Evaluation of the Accuracy of the Subtraction Method Used for Determining Platelet Counts in Advanced Platelet-Rich Fibrin and Concentrated Growth Factor Preparations

PubMed Central

Watanabe, Taisuke; Isobe, Kazushige; Suzuki, Taiji; Kawabata, Hideo; Nakamura, Masayuki; Tsukioka, Tsuneyuki; Okudera, Toshimitsu; Okudera, Hajime; Uematsu, Kohya; Okuda, Kazuhiro; Nakata, Koh; Kawase, Tomoyuki

2017-01-01

Platelet concentrates should be quality-assured of purity and identity prior to clinical use. Unlike for the liquid form of platelet-rich plasma, platelet counts cannot be directly determined in solid fibrin clots and are instead calculated by subtracting the counts in other liquid or semi-clotted fractions from those in whole blood samples. Having long suspected the validity of this method, we herein examined the possible loss of platelets in the preparation process. Blood samples collected from healthy male donors were immediately centrifuged for advanced platelet-rich fibrin (A-PRF) and concentrated growth factors (CGF) according to recommended centrifugal protocols. Blood cells in liquid and semi-clotted fractions were directly counted. Platelets aggregated on clot surfaces were observed by scanning electron microscopy. A higher centrifugal force increased the numbers of platelets and platelet aggregates in the liquid red blood cell fraction and the semi-clotted red thrombus in the presence and absence of the anticoagulant, respectively. Nevertheless, the calculated platelet counts in A-PRF/CGF preparations were much higher than expected, rendering the currently accepted subtraction method inaccurate for determining platelet counts in fibrin clots. To ensure the quality of solid types of platelet concentrates chairside in a timely manner, a simple and accurate platelet-counting method should be developed immediately. PMID:29563413

A Case Report of Drug-Induced Thrombocytopenia after Living Donor Liver Transplantation

PubMed Central

ARAI, KEISUKE; KURAMITSU, KAORI; FUKUMOTO, TAKUMI; KIDO, MASAHIRO; TAKEBE, ATSUSHI; TANAKA, MOTOFUMI; KINOSHITA, HISOKA; AJIKI, TETSUO; TOYAMA, HIROCHIKA; ASARI, SADAKI; GOTO, TADAHIRO; KU, YONSON

2016-01-01

There are few descriptions of severe thrombocytopenia during the early postoperative period after liver transplantation, and these have not been fully documented in the literature. Here, we report a case of drug-induced thrombocytopenia requiring transfusion of blood products after living donor liver transplantation. We determined that this was not caused by the interferon-free anti-viral therapy but by tacrolimus A 61-year-old woman with hepatitis C-related cirrhosis and hepatorenal syndrome underwent living donor liver transplantation using a left lobe graft from her son. After transplantation, immunosuppression consisted of tacrolimus and steroid. Seven weeks after transplantation, interferon-free therapy with daclatasvir and asunaprevir was started. Thirteen days thereafter, hepatitis C virus tested negative. However, the platelet count had begun to gradually decrease just before starting anti-viral therapy. Daclatasvir and asunaprevir were stopped because this was suspected to be a side-effect of these drugs, but the patient nonetheless went on to develop severe thrombocytopenia (platelet count 17,000/μL), which needed transfusions. Now suspecting tacrolimus as the inducer of this side effect, we changed to cyclosporin, after which the platelet count gradually recovered. Viral markers were still not detectable up to 2 months after discontinuation of the antiviral drugs. We conclude that when severe thrombocytopenia occurs, possible drug-induced thrombocytopenia as well as other disorders must be investigated. PMID:27492209

How do people become plasma and platelet donors in a VNR context?

PubMed

Charbonneau, Johanne; Cloutier, Marie-Soleil; Fainstein, Balia

2017-08-25

The demand for therapeutic plasma-derived products poses a challenge to blood collection agencies (BCAs). In 2014-2015, the volume of plasma sent for fractionation met 17.7% of Quebec's needs for immunoglobulins. This article aims to offer an exploration of the paths blood donors follow in order to become plasma and platelet donors (PPDs). This analysis is based on semi-structured interviews with 50 PPDs in Quebec, Canada. Our analysis focused on the occurrence of events and the presence of contextual elements identified through: (1) factual data on PPDs; and (2) what PPDs identified as being an influence on their donation experience. This information was synthesized using a typology of trajectories. Six typical trajectories have been distinguished, first by the presence (19/50 respondents) or absence (31/50) of blood donation as a family tradition. Of the latter 31 donors, some pointed instead to inherited family values as having a significant influence on their commitment (11/31). Donors' careers were then distinguished as having started early (34) or late (16). Sub-types then appeared with the addition of other contextual elements, motivation profiles, and circumstances under which the conversion to apheresis donation occurred. Our findings suggest the existence of diversified donor trajectories, and confirm the importance of conducting more in-depth analyses of the sequence of events occurring along PPDs career. BCAs should develop strategies carefully tailored to different potential clienteles if they wish to convert whole blood donors to apheresis donation, and also focus on recruiting and retaining young PPDs. © 2017 The Authors. Journal of Clinical Apheresis Published by Wiley Periodicals, Inc.

Relative safety of pooled whole blood-derived versus single-donor (apheresis) platelets in the United States: a systematic review of disparate risks.

PubMed

Vamvakas, Eleftherios C

2009-12-01

Risks of transfusion-transmitted infections (TTIs), transfusion-associated sepsis (TAS), and transfusion-related acute lung injury (TRALI) were compared between pooled whole blood-derived (PWBD) and single-donor platelets (PLTs) transfused in the United States. The literature was searched for estimates of the risk of TTIs and TAS and of the effect on bacterial contamination of PLTs of process improvements, bacterial culture, and surrogate methods to detect bacteria. Seven studies published between January 2005 and December 2008 and comparing bacterial contamination frequency between PWBD and single-donor PLTs after implementing bacterial culture testing of both components were subjected to meta-analysis. The three retrieved studies diagnosing TRALI based on the 2004 consensus definition in settings transfusing both PWBD and single-donor PLTs were not amenable to meta-analysis and were assessed qualitatively. Under a best-case scenario, if 100% (from the current 12.5%) of PLT doses were provided as PWBD PLTs, the number of additional transmissions of human immunodeficiency virus, hepatitis C virus, hepatitis B virus, bacteria, or a novel pathogen annually could be 1.2, 1.3, 9.0, 105.3, or 69.2 to 252.6, respectively. Compared with single-donor PLTs, US PLT pools of five concentrates have a 5.6-fold higher risk of bacterial contamination (summary odds ratio, 5.58; 95% confidence interval, 2.60-11.98; p < 0.05). The three studies that diagnosed TRALI based on the consensus definition did not demonstrate a difference in risk between PWBD and single-donor PLTs. TTIs and TAS determine the relative safety of PWBD versus single-donor PLTs. The available limited data do not support a higher risk of TRALI from single-donor (compared with PWBD) PLTs.

Frequency of adverse events in plateletpheresis donors in regional transfusion centre in North India.

PubMed

Patidar, Gopal Kumar; Sharma, Ratti Ram; Marwaha, Neelam

2013-10-01

Although automated cell separators have undergone a lot of technical refinements, attention has been focused on the quality of platelet concentrates than on donor safety. We planned this prospective study to look into donor safety aspect by studying adverse events in normal healthy plateletpheresis donors. The study included 500 healthy, first-time (n=301) and repeat (n=199) plateletpheresis donors after informed consent. The plateletpheresis procedures were performed on Trima Accel (5.1 version, GAMBRO BCT) and Amicus (3.2 version FENWAL) cell separators. The adverse events during procedure were recorded and classified according to their nature. The pre and post procedure hematological and biochemical profiles of these donors were also assessed with the help of automated cell counter and analyser respectively. A total of 18% (n=90) adverse events were recorded in 500 plateletpheresis donors, of which 9% of were hypocalcaemia in nature followed by hematoma (7.4%), vasovagal reaction (0.8%) and kit related adverse events in (0.8%). There was significant post procedure drop in Hb, Hct, platelet count of the donors (p<0.0001) whereas WBC count showed a statistically significant rise (p<0.0001). Divalent cations (iCa(+), TCa(+), TMg(+)) also showed a statistically significant decline after donation (p<0.0001). However there were no statistically significance difference between adverse events in Trima Accel (5.1 version, GAMBRO BCT) and Amicus (3.2 version FENWAL) cell separators. Donor reactions can adversely affect the voluntary donor recruitment strategies to increase the public awareness regarding constant need for blood and blood products. Commonly observed adverse events in plateletpheresis donors were hypocalcemia, hematoma formation and vasovagal reactions which can be prevented by pre-donation education of the donors and change of machine configuration. Nevertheless, more prospective studies on this aspect are required in order to establish guidelines for donor safety in apheresis and also to help in assessing donor suitability, especially given the present trend of double product apheresis collections. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of a Strategy Based on the Surface Plasmon Resonance Technology for Platelet Compatibility Testing.

PubMed

Wu, Chang-Lin; He, Jian-An; Gu, Da-Yong; Shao, Chao-Peng; Zhu, Yi; Dang, Xin-Tang

2018-01-01

This study was aimed to establish a novel strategy based on the surface plasmon resonance (SPR) technology for platelet compatibility testing. A novel surface matrix was prepared based on poly (OEGMA-co-HEMA) via surface-initiated polymerization as a biosensor surface platform. Type O universal platelets and donor platelets were immobilized on these novel matrices via amine-coupling reaction and worked as a capturing ligand for binding the platelet antibody. Antibodies binding to platelets were monitored in real time by injecting the samples into a microfluidic channel. Clinical serum samples (n = 186) with multiple platelet transfusions were assayed for platelet antibodies using the SPR technology and monoclonal antibody-immobilized platelet antigen (MAIPA) assay. The novel biosensor surface achieved nonfouling background and high immobilization capacity and showed good repeatability and stability after regeneration. The limit of detection of the SPR biosensor for platelet antibody was estimated to be 50 ng/mL. The sensitivity and specificity were 92% and 98.7%. It could detect the platelet antibody directly in serum samples, and the results were similar to MAIPA assay. A novel strategy to facilitate the sensitive and reliable detection of platelet compatibility for developing an SPR-based biosensor was established in this study. The SPR-based biosensor combined with novel surface chemistry is a promising method for platelet compatibility testing.

Human platelet antigen genotypes in Turkish and Caucasian blood donors in Germany.

PubMed

Hauck-Dlimi, B; Hammon, K; Eckstein, R; Ott, S; Zimmermann, R; Dengler, T; Ringwald, J

2012-09-01

Exposition to allogenic human platelet antigens (HPAs) can lead to antibody formation causing neonatal alloimmune thrombocytopenia (NAIT), post-transfusion purpura or platelet (PLT) transfusion refractoriness. The frequencies of HPA differ between ethnical groups which could be associated with different potential alloimmunization risk. The Turkish population is the largest ethnic minority group living in Germany. However, no data are available about the HPA frequency among Turkish population. We compared the frequency of HPA between Caucasian and Turkish blood donors. DNA from blood samples of 119 Caucasian and 117 Turkish blood donors was isolated. The genotype of HPA-1, -2, -3 -4, -5 and -15 was determined using a commercialized polymerase chain reaction kit with sequence-specific primers. In Turkish blood donors, the gene frequencies of HPA-1a/1b, -2a/2b, -3a/3b, -4a/4b, -5a/5b and -15a/15b were 0.863/0.137, 0.868/0.133, 0.607/0.393, 0.996/0.004, 0.893/0.107 and 0.474/0.256, respectively. In Caucasians, we observed 0.798/0.202, 0.908/0.092, 0.567/0.432, 1.000/0.000, 0.916/0.084 and 0.517/0.483 for HPA-1a/1b, -2a/2b, -3a/3b, -4a/4b, -5a/5b and -15a/15b, respectively. No statistically significant difference between genotypes in these populations could be observed. Due to the similar distribution of HPA genotypes in both ethnical groups, no increased risk of NAIT for children of mixed couples or of post-transfusion purpura or PLT transfusion refractoriness secondary to antibodies to HPAs for recipients of PLT concentrates from blood donors of the other ethnicity is given. © 2012 John Wiley & Sons A/S.

Prevalence, serologic and genetic studies of high expressers of the blood group A antigen on platelets*

PubMed Central

Sant’Anna Gomes, B M; Estalote, A C; Palatnik, M; Pimenta, G; Pereira, B de B; do Nascimento, E M

2010-01-01

Objective/Aim: The aim of this study is to describe the distribution of the platelet blood group A antigenicity in Euro-Brazilians (EUBs) and Afro-Brazilians (AFBs). Background: A small but significant proportion of individuals express high levels of A or B antigen on their platelets corresponding to the erythrocyte ABO group. The mechanism of increased antigen expression has not been elucidated. Material/Methods: A cohort of 241 blood group A donors was analysed by flow cytometry. Although mean fluorescence intensity (MFI) is a typical continuous variable, platelets were screened and divided into two categories: low expressers (LEs) and high expressers (HEs). A three-generation family was investigated looking for an inheritance mechanism. Results: The prevalence of the HE platelet phenotype among group A1 donors was 2%. The mean of MFI on platelets of A1 subgroup of EUBs differs from that of AFBs (P = 0·0115), whereas the frequency of the HE phenotype was similar between them (P = 0·5251). A significant difference was found between sexes (P = 0·0039). Whereas the serum glycosyltransferase from HE family members converted significantly more H antigen on group O erythrocytes into A antigens compared with that in LE serum, their ABO, FUT1 and FUT2 genes were consensus. The theoretically favourable, transcriptionally four-repeat ABO enhancer was not observed. Conclusion: The occurrence of HE in several members suggests familial aggregation. Indeed, in repeated measures, stability of the MFI values is suggesting an inherited condition. Factors outside the ABO locus might be responsible for the HE phenotype. Whether the real mechanism of inheritance is either of a polygenic or of a discrete Mendelian nature remains to be elucidated. PMID:20553427

[In-line leukocyte depletion ov thrombocytapheresis concentrates with the Fresenius-AS-104 cell separator].

PubMed

Zeiler, T; Kretschmer, V

1997-01-01

This study reports on in-line filtration of 72 platelet concentrates (PC) collected by the Fresenius AS 104 cell separator, using the new C4F sets with integrated leukocyte filters (Biofil P plus). 72 volunteer donors, automatic counts of platelets, microscopical counting of residual leukocytes with the Nageotte chamber, GMP-140 by flow cytometrie, beta-thromboglobulin release, platelet aggregation (ADP, collagen). Filtration reduced leukocytes by 98.5%. Residual leukocyte contamination remained clearly below 5 x 10(6) (mean 0.5 +/- 0.6 x 10(6), maximum 2.8 x 10(6). Platelet loss by filtration was found to be between 27.4 and 0.7% (median 8.5%). Filtration caused a significant decrease of platelet aggregability (p < 0.005), but no significant increase of beta-thromboglobulin release and only a slight decrease of GMP-140 expression. From these data can be concluded that in-line filtration was highly efficient with acceptable platelet retention. No significant platelet activation could be observed in the PC. The decrease of platelet aggregability have been due to the reduction of activated platelets which are believed to show reduced in vivo survival.

A Rare Case of Transfusion Transmission of Hepatitis A Virus to Two Patients with Haematological Disease

PubMed Central

da Silva, Suely Gonçalves Cordeiro; Leon, Luciane Almeida Amado; Alves, Gilda; Brito, Selma Magalhães; Sandes, Valcieny de Souza; Lima, Magda Maria Adorno Ferreira; Nogueira, Marta Colares; Tavares, Rita de Cássia Barbosa da Silva; Dobbin, Jane; Apa, Alexandre; de Paula, Vanessa Salete; Oliveira, Jaqueline Mendes de Oliveira; Pinto, Marcelo Alves; Ferreira Jr, Orlando da Costa; Motta, Iara de Jesus Ferreira

2016-01-01

Summary Background This paper describes the transmission of hepatitis A virus (HAV) to two blood recipients from a healthy donor that later presented to the blood bank with jaundice. Methods The RNA of HAV was detected by qualitative nested reverse transcription polymerase chain reaction (nested RT-PCR) and quantified by real-time RT-PCR. HAV RNA samples were genotyped by direct sequencing of PCR products. A sequence from a fragment of 168 bp from the VP1/2A HAV region was used to construct a phylogenetic tree. Case Report A 31-year-old male donor accepted for donation of a whole blood unit returned to the blood bank with clinical jaundice 20 days after donation. His serological and NAT tests were negative for HBV and HCV. Serological tests for HAV IgM and IgG were negative on donation sample but positive on follow-up sample, confirming donor's HAV acute infection. Both recipients of red blood cells (R1) and platelet concentrate (R2) from the same implicated donation were HAV IgM-negative and IgG-positive. Qualitative PCR was positive on samples from all three individuals and phylogenetic analysis of viruses proved HAV transmission to the two recipients of blood products. HAV viral load on donor follow-up sample and the platelet recipient was 1.3 and 1.5 × 103 IU/ml, respectively. The RBC recipient, also infected by HCV, was undergoing bone marrow transplantation and died from fulminant hepatitis, 26 days after the implicated HAV transfusion. Conclusion The blood donor, a garbage collector, spontaneously returned to the blood bank when developing jaundice. This highlights the importance of donor education to immediately report to blood banks of any signs and symptoms related to infectious disease developed after blood donation. The fact that one immunocompromised patient with HCV infection died from fulminant hepatitis after receiving a HAV-contaminated platelet transfusion underpins the importance of a HAV vaccination program for these group of patients. PMID:27226795

Comparison of the inhibitory effects of cilostazol, acetylsalicylic acid and ticlopidine on platelet functions ex vivo. Randomized, double-blind cross-over study.

PubMed

Ikeda, Y; Kikuchi, M; Murakami, H; Satoh, K; Murata, M; Watanabe, K; Ando, Y

1987-05-01

A randomized double-blind cross-over study was conducted to determine the inhibitory effects of acetylsalicylic acid (ASA), ticlopidine (TP) and cilostazol (OPC-13013; in the following briefly called CS), a new antithrombotic agent on platelet functions ex vivo. Nine patients with cerebral thrombosis were enrolled in this study. Patients were given each of the three drugs for one week in a complete cross-over design according to a randomization schedule, followed by a wash-out period with a placebo for one week. It was found that CS and TP significantly inhibited platelet aggregation induced by ADP. Collagen- and arachidonic acid-induced platelet aggregation was all inhibited by CS, TP and ASA. Duncan's multiple range test to compare the anti-platelet effects of the three drugs revealed that: CS greater than ASA and TP greater than ASA in inhibiting ADP-induced platelet aggregation and CS greater than TP and ASA greater than TP in inhibiting arachidonic acid-induced platelet aggregation. These results may suggest that CS is superior to ASA and TP in inhibiting platelet aggregation ex vivo.

[Transfusion supply optimization in multiple-discipline surgical hospital].

PubMed

Solov'eva, I N; Trekova, N A; Krapivkin, I A

2016-01-01

To define optimal variant of transfusion supply of hospital by blood components and to decrease donor blood expense via application of blood preserving technologies. Donor blood components expense, volume of hemotransfusions and their proportion for the period 2012-2014 were analyzed. Number of recipients of packed red cells, fresh-frozen plasma and packed platelets reduced 18.5%, 25% and 80% respectively. Need for donor plasma decreased 35%. Expense of autologous plasma in cardiac surgery was 76% of overall volume. Preoperative plasma sampling is introduced in patients with aortic aneurysm. Number of cardiac interventions performed without donor blood is increased 7-31% depending on its complexity.

In vitro properties of concentrated canine platelets stored in two additive solutions: a comparative study.

PubMed

Hlavac, N; Lasta, C S; Dalmolin, M L; Lacerda, L A; de Korte, D; Marcondes, N A; Terra, S R; Fernandes, F B; González, F H D

2017-11-15

Platelet transfusion therapy poses many challenges in veterinary clinical practice. Lack of readily available blood donors, short shelf-life, and inability to administer a sufficient number of platelets to meet a dog's transfusion need are the major difficulties encountered. Platelet additive solutions are already in use at American and European human blood banks, showing to be a realistic alternative. This study compares the in vitro platelet function in plasma, Composol, or SSP+ during storage for 13 days. Platelet rich plasma-platelet concentrate with 35% plasma and 65% platelet additive solutions (Composol or SSP+) and a control group (100% plasma) were prepared. Swirling, platelet count, blood gases, metabolic variables, platelet activation markers, and apoptosis markers were analyzed on days 1, 5, 9 and 13. Swirling was well preserved and pH was acceptable (> 6.2) during storage for all platelet additive solutions units until day 9. SSP + units showed more stable pH and metabolic variables until day 13. Platelets in plasma showed higher glucose consumption than in Composol or in SSP+. The platelet additive solutions units showed better platelet metabolism maintenance, reduced glucose consumption and lactate production. The apoptotic markers were still low for 9 days in platelet concentrates with platelet additive solutions, suggesting the possibility to extend the shelf life with the use of SSP+ or Composol. Our findings suggest that the uses of Composol and SSP+ in canine platelet concentrates are potential alternatives in veterinary blood banks.

Whole blood and apheresis donors in Quebec, Canada: Demographic differences and motivations to donate.

PubMed

Charbonneau, Johanne; Cloutier, Marie-Soleil; Carrier, Élianne

2015-12-01

This study sought to compare demographics and donation motivations among plasma/platelet donors (PPDs) and whole blood donors (WBDs), in a voluntary and non-remunerated context. Motives to donate blood and demographic characteristics were collected through questionnaires completed by 795 WBDs and 473 PPDs. Comparison of WBDs and PPDs under chi-square tests showed that 17 out of 23 motivators were statistically different according to various demographic variables. These results demonstrate the existence of specific donor profiles both for WBDs and PPDs. Agencies should develop new recruitment strategies tailored to these donors, especially if they wish to convince WBDs to convert to apheresis donation. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Collection, storage, inspection and quality control of platelet concentrates obtained by apheresis: The situation in Spain.

PubMed

Castrillo, Azucena; Jimenez-Marco, Teresa; Arroyo, José L; Jurado, María L; Larrea, Luis; Maymo, Rosa M; Monge, Jorge; Muñoz, Carmen; Pajares, Ángel; Yáñez, Marta

2017-06-01

Diverse variables are involved in apheresis platelet collection, processing and storage. This survey shows how these are realized in Spain. An analysis of collected data was performed in a questionnaire completed by ten Transfusion Centers (TC) which perform between 50 and 520 apheresis procedures per month. This information comprises the procedures used to collect, inspect and store apheresis platelet concentrates (PC), and quality control data. Macroscopic inspection of PC is performed in all TC, especially during the first few hours post-collection and before distribution. The type of processor, duration of post-collection resting periods and temperature from the time of collection until distribution are similar in all TC. In 80% of TC, PC with small and scarce aggregates are distributed to transfusion services. The presence of clumps is influenced by type of processor, female donor, cold ambient temperature and collection of hyperconcentrated platelets, and is often recurrent in the same donor, although some TC have not found any influential variables. Overall, no objective inspection methods are followed, although there are exceptions. The degree of compliance with quality control parameters, such as the number of units studied, mean platelet yield, residual leukocyte counts and pH at expiry date, is acceptable in all TC. Compliance in terms of number of microbiological culture samples is variable. The usual practice in Spanish TC with respect to the collection, post-collection handling and storage of apheresis PC can be considered uniform, although some specific aspects of analyses should follow more objective methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

The feed gas composition determines the degree of physical plasma-induced platelet activation for blood coagulation

NASA Astrophysics Data System (ADS)

Bekeschus, Sander; Brüggemeier, Janik; Hackbarth, Christine; Weltmann, Klaus-Dieter; von Woedtke, Thomas; Partecke, Lars-Ivo; van der Linde, Julia

2018-03-01

Cold atmospheric (physical) plasma has long been suggested to be a useful tool for blood coagulation. However, the clinical applicability of this approach has not been addressed sufficiently. We have previously demonstrated the ability of a clinically accepted atmospheric pressure argon plasma jet (kINPen® MED) to coagulate liver incisions in mice with similar performance compared to the gold standard electrocauterization. We could show that plasma-mediated blood coagulation was dependent on platelet activation. In the present work, we extended on this by investigating kINPen®-mediated platelet activation in anticoagulated human donor blood ex vivo. With focus on establishing high-throughput, multi-parametric platelet activation assays and performing argon feed gas parameter studies we achieved the following results: (i) plasma activated platelets in heparinized but not in EDTA-anticoagulated blood; (ii) plasma decreased total platelet counts but increased numbers of microparticles; (iii) plasma elevated the expression of several surface activation markers on platelets (CD62P, CD63, CD69, and CD41/61); (iv) in platelet activation, wet and dry argon plasma outperformed feed gas admixtures with oxygen and/or nitrogen; (v) plasma-mediated platelet activation was accompanied by platelet aggregation. Platelet aggregation is a necessary requirement for blood clot formation. These findings are important to further elucidate molecular details and clinical feasibility of cold physical plasma-mediated blood coagulation.

Platelet proteome reveals novel pathways of platelet activation and platelet-mediated immunoregulation in dengue.

PubMed

Trugilho, Monique Ramos de Oliveira; Hottz, Eugenio Damaceno; Brunoro, Giselle Villa Flor; Teixeira-Ferreira, André; Carvalho, Paulo Costa; Salazar, Gustavo Adolfo; Zimmerman, Guy A; Bozza, Fernando A; Bozza, Patrícia T; Perales, Jonas

2017-05-01

Dengue is the most prevalent human arbovirus disease worldwide. Dengue virus (DENV) infection causes syndromes varying from self-limiting febrile illness to severe dengue. Although dengue pathophysiology is not completely understood, it is widely accepted that increased inflammation plays important roles in dengue pathogenesis. Platelets are blood cells classically known as effectors of hemostasis which have been increasingly recognized to have major immune and inflammatory activities. Nevertheless, the phenotype and effector functions of platelets in dengue pathogenesis are not completely understood. Here we used quantitative proteomics to investigate the protein content of platelets in clinical samples from patients with dengue compared to platelets from healthy donors. Our assays revealed a set of 252 differentially abundant proteins. In silico analyses associated these proteins with key molecular events including platelet activation and inflammatory responses, and with events not previously attributed to platelets during dengue infection including antigen processing and presentation, proteasome activity, and expression of histones. From these results, we conducted functional assays using samples from a larger cohort of patients and demonstrated evidence for platelet activation indicated by P-selectin (CD62P) translocation and secretion of granule-stored chemokines by platelets. In addition, we found evidence that DENV infection triggers HLA class I synthesis and surface expression by a mechanism depending on functional proteasome activity. Furthermore, we demonstrate that cell-free histone H2A released during dengue infection binds to platelets, increasing platelet activation. These findings are consistent with functional importance of HLA class I, proteasome subunits, and histones that we found exclusively in proteome analysis of platelets in samples from dengue patients. Our study provides the first in-depth characterization of the platelet proteome in dengue, and sheds light on new mechanisms of platelet activation and platelet-mediated immune and inflammatory responses.

Platelet proteome reveals novel pathways of platelet activation and platelet-mediated immunoregulation in dengue

PubMed Central

Teixeira-Ferreira, André; Carvalho, Paulo Costa; Salazar, Gustavo Adolfo; Zimmerman, Guy A.; Perales, Jonas

2017-01-01

Dengue is the most prevalent human arbovirus disease worldwide. Dengue virus (DENV) infection causes syndromes varying from self-limiting febrile illness to severe dengue. Although dengue pathophysiology is not completely understood, it is widely accepted that increased inflammation plays important roles in dengue pathogenesis. Platelets are blood cells classically known as effectors of hemostasis which have been increasingly recognized to have major immune and inflammatory activities. Nevertheless, the phenotype and effector functions of platelets in dengue pathogenesis are not completely understood. Here we used quantitative proteomics to investigate the protein content of platelets in clinical samples from patients with dengue compared to platelets from healthy donors. Our assays revealed a set of 252 differentially abundant proteins. In silico analyses associated these proteins with key molecular events including platelet activation and inflammatory responses, and with events not previously attributed to platelets during dengue infection including antigen processing and presentation, proteasome activity, and expression of histones. From these results, we conducted functional assays using samples from a larger cohort of patients and demonstrated evidence for platelet activation indicated by P-selectin (CD62P) translocation and secretion of granule-stored chemokines by platelets. In addition, we found evidence that DENV infection triggers HLA class I synthesis and surface expression by a mechanism depending on functional proteasome activity. Furthermore, we demonstrate that cell-free histone H2A released during dengue infection binds to platelets, increasing platelet activation. These findings are consistent with functional importance of HLA class I, proteasome subunits, and histones that we found exclusively in proteome analysis of platelets in samples from dengue patients. Our study provides the first in-depth characterization of the platelet proteome in dengue, and sheds light on new mechanisms of platelet activation and platelet-mediated immune and inflammatory responses. PMID:28542641

Patellar tendon healing with platelet-rich plasma: a prospective randomized controlled trial.

PubMed

de Almeida, Adriano Marques; Demange, Marco Kawamura; Sobrado, Marcel Faraco; Rodrigues, Marcelo Bordalo; Pedrinelli, André; Hernandez, Arnaldo José

2012-06-01

The patellar tendon has limited ability to heal after harvesting its central third. Platelet-rich plasma (PRP) could improve patellar tendon healing. Adding PRP to the patellar tendon harvest site would improve donor site healing and improve clinical outcome at 6 months after anterior cruciate ligament (ACL) reconstruction with a patellar tendon graft. Randomized controlled trial; Level of evidence, 1. Twenty-seven patients were randomly divided to receive (n = 12) or not receive (n = 15) PRP in the patellar tendon harvest site during ACL reconstruction. The primary outcome was magnetic resonance imaging (MRI) assessment of patellar tendon healing (gap area) after 6 months. Secondary outcomes were questionnaires and isokinetic testing of ACL reconstruction with a patellar tendon graft comparing both groups. Patellar tendon gap area was significantly smaller in the PRP group (4.9 ± 5.3 mm(2); 95% confidence interval [CI], 1.1-8.8) than in the control group (9.4 ± 4.4 mm(2); 95% CI, 6.6-12.2; P = .046). Visual analog scale score for pain was lower in the PRP group immediately postoperatively (3.8 ± 1.0; 95% CI, 3.18-4.49) than in the control group (5.1 ± 1.4; 95% CI, 4.24-5.90; P = .02). There were no differences after 6 months in questionnaire and isokinetic testing results comparing both groups. We showed that PRP had a positive effect on patellar tendon harvest site healing on MRI after 6 months and also reduced pain in the immediate postoperative period. Questionnaire and isokinetic testing results were not different between the groups at 6 months.

Reduction of pain via platelet-rich plasma in split-thickness skin graft donor sites: a series of matched pairs

PubMed Central

Miller, John D.; Rankin, Timothy M.; Hua, Natalie T.; Ontiveros, Tina; Giovinco, Nicholas A.; Mills, Joseph L.; Armstrong, David G.

2015-01-01

In the past decade, autologous platelet-rich plasma (PRP) therapy has seen increasingly widespread integration into medical specialties. PRP application is known to accelerate wound epithelialization rates, and may also reduce postoperative wound site pain. Recently, we observed an increase in patient satisfaction following PRP gel (Angel, Cytomedix, Rockville, MD) application to split-thickness skin graft (STSG) donor sites. We assessed all patients known to our university-based hospital service who underwent multiple STSGs up to the year 2014, with at least one treated with topical PRP. Based on these criteria, five patients aged 48.4±17.6 (80% male) were identified who could serve as their own control, with mean time of 4.4±5.1 years between operations. In both therapies, initial dressing changes occurred on postoperative day (POD) 7, with donor site pain measured by Likert visual pain scale. Paired t-tests compared the size and thickness of harvested skin graft and patient pain level, and STSG thickness and surface area were comparable between control and PRP interventions (p>0.05 for all). Donor site pain was reduced from an average of 7.2 (±2.6) to 3 (±3.7), an average reduction in pain of 4.2 (standard error 1.1, p=0.0098) following PRP use. Based on these results, the authors suggest PRP as a beneficial adjunct for reducing donor site pain following STSG harvest. PMID:25623477

Establishing Assay Cutoffs for HLA Antibody Screening of Apheresis Donors

PubMed Central

Carrick, Danielle M.; Norris, Philip J.; Endres, Robert O.; Pandey, Suchitra; Kleinman, Steven H.; Wright, David; Sun, Yu; Busch, Michael P.

2011-01-01

BACKGROUND TRALI is the leading cause of transfusion-related deaths. Donor HLA antibodies have been implicated in TRALI cases. Blood centers are implementing TRALI risk reduction strategies based on HLA antibody screening of some subpopulations of ever-pregnant apheresis platelet donors. However, if screening assay cutoffs are too sensitive, donation loss may adversely impact blood availability. STUDY DESIGN Pregnancy history and HLA antibody screening and single antigen bead (SAB) data from blood donors in the REDS-II Leukocyte Antibody Prevalence Study (LAPS) were evaluated for correlations between assay screening values, HLA antibody titer, and number of HLA antigen specificities. The probabilities of matching a cognate antigen in a recipient were calculated and examined in association with total number of specificities observed and screening values. The relative impact of imposing various screening assay cutoffs or pregnancy stratification was examined in relation to detection of HLA antibody reactive donations and loss of donors and donations. RESULTS We provide evidence that higher HLA Ab screening assay values are associated with maintaining higher screening signals upon dilution and an increased breadth of specificities compared with lower screening values; the latter correlated with an increased risk of a cognate antigen match in potential recipients. Depending upon the TRALI risk reduction strategy used, the potential loss of donations ranged between 0.9 and 6.0%. CONCLUSION This analysis should enable blood centers to decide upon a TRALI risk reduction strategy for apheresis platelets that is consistent with how much donation loss the blood center can tolerate. PMID:21332726

Platelet glycoproteins associated with aspirin-treatment upon platelet activation

PubMed Central

Shah, Punit; Yang, Weiming; Sun, Shisheng; Pasay, Jered; Faraday, Nauder; Zhang, Hui

2017-01-01

Platelet glycoproteins are known to play central roles in hemostasis and vascular integrity and have pathologic roles in vascular occlusive diseases such as myocardial infarction and stroke. Characterizing glycoproteins within and secreted by platelets can provide insight into the mechanisms that underlie vascular pathologies and the therapeutic benefits or failure of anti-platelet agents. To study the impact of aspirin, which is commonly prescribed for primary and secondary cardiovascular prevention, on the platelet glycoproteome, we evaluated washed platelets from ten donors. The platelet glycoproteome, was studied using an iTRAQ in resting and stimulated states and with and without aspirin treatment. Using solid phase extraction of glycosite-containing peptides (SPEG), we were able to identify 799 unique N-linked glycosylation sites (glycosites) in platelets, representing the largest and the most comprehensive analysis to date. We were able to identity a number of glycoproteins impacted by aspirin treatment, which we validated using global proteomics analysis of platelets and their secreted proteins. In our analyses, metallopeptidase inhibitor 1 (TIMP1) was the single most significantly affected glycoprotein by aspirin treatment. ELISA assays confirmed proteomic results and validated our strategy. Functional analysis demonstrated that TIMP1 levels were highly correlated with platelet reactivity in vitro, with a correlation coefficient of −0.5. The release of TIMP1 from platelets, which was previously unknown to be affected by aspirin treatment, may play important roles in hemostasis and/or vascular integrity. If validated, our findings may be useful for developing assays that assess platelet response to aspirin or other anti-platelet therapies. PMID:27452734

Rapid Evaluation of Platelet Function With T2 Magnetic Resonance

PubMed Central

Cuker, Adam; Husseinzadeh, Holleh; Lebedeva, Tatiana; Marturano, Joseph E.; Massefski, Walter; Lowery, Thomas J.; Lambert, Michele P.; Abrams, Charles S.; Weisel, John W.

2016-01-01

Objectives: The clinical diagnosis of qualitative platelet disorders (QPDs) based on light transmission aggregometry (LTA) requires significant blood volume, time, and expertise, all of which can be barriers to utilization in some populations and settings. Our objective was to develop a more rapid assay of platelet function by measuring platelet-mediated clot contraction in small volumes (35 µL) of whole blood using T2 magnetic resonance (T2MR). Methods: We established normal ranges for platelet-mediated clot contraction using T2MR, used these ranges to study patients with known platelet dysfunction, and then evaluated agreement between T2MR and LTA with arachidonic acid, adenosine diphosphate, epinephrine, and thrombin receptor activator peptide. Results: Blood from 21 healthy donors was studied. T2MR showed 100% agreement with LTA with each of the four agonists and their cognate inhibitors tested. T2MR successfully detected abnormalities in each of seven patients with known QPDs, with the exception of one patient with a novel mutation leading to Hermansky-Pudlak syndrome. T2MR appeared to detect platelet function at similar or lower platelet counts than LTA. Conclusions: T2MR may provide a clinically useful approach to diagnose QPDs using small volumes of whole blood, while also providing new insight into platelet biology not evident using plasma-based platelet aggregation tests. PMID:28028118

Effects of clopidogrel and aspirin in combination versus aspirin alone on platelet activation and major receptor expression in patients after recent ischemic stroke: for the Plavix Use for Treatment of Stroke (PLUTO-Stroke) trial.

PubMed

Serebruany, Victor L; Malinin, Alex I; Ziai, Wendy; Pokov, Alex N; Bhatt, Deepak L; Alberts, Mark J; Hanley, Dan F

2005-10-01

Clopidogrel is widely used in patients after recent ischemic stroke; however, its ability to yield additional antiplatelet protection on top of aspirin has never been explored in a controlled study. To determine whether clopidogrel with aspirin (C+ASA) will produce more potent platelet inhibition than aspirin alone (ASA) in patients after ischemic stroke, we conducted the Plavix Use for Treatment of Stroke trial. Seventy patients after ischemic stroke were randomly assigned to C+ASA or ASA groups. Platelet studies included aggregometry; cartridge-based analyzers; expression of PECAM-1, P-selectin, GP IIb/IIIa (antigen and activity), vitronectin receptor, and formation of platelet-leukocyte microparticles by flow cytometry. Platelet tests were performed at baseline and after 30 days after randomization. There were no deaths, hospitalizations, or serious adverse events. There were no differences in the baseline platelet characteristics between C+ASA and ASA groups, or significant changes in platelet parameters in the ASA group, except diminished collagen-induced aggregation (P=0.001). In contrast, therapy with C+ASA resulted in a significant inhibition of platelet activity assessed by ADP- (P=0.00001) and collagen-induced (P=0.02) aggregation; closure time prolongation (P=0.03), and reduction of platelet activation units with Ultegra (P=0.00001); expression of PECAM-1 (P=0.01), and GP IIb/IIIa activity with PAC-1 (P=0.02) when compared with ASA group. Therapy with C+ASA also resulted in the reduced formation of platelet-leukocyte microparticles (P=0.02). Treatment with C+ASA for 1 month provides significantly greater inhibition of platelet activity than ASA alone in patients after recent ischemic stroke in the frame of the small randomized trial.

In vitro evaluation of COM.TEC apheresis platelet concentrates using a preparation set and pathogen inactivation over a storage period of five days.

PubMed

Moog, R; Fröhlich, A; Mayaudon, V; Lin, L

2004-01-01

The aim of the present study was to evaluate in vitro data on platelets collected by apheresis, processed on a preparation set followed by photochemical treatment (PCT). Fifteen single-donor platelet concentrates (PCs) were collected by apheresis (COM.TEC blood cell separator, Fresenius, Bad Homburg, Germany). The platelets were transferred to the preparation set and plasma was removed after centrifugation to resuspend the platelets in approximately 37% plasma and 63% platelet additive solution InterSol. PCT was done by exposing the platelets to amotosalen HCl followed by illumination with ultraviolet light. Blood cell counts and in vitro PLT function were measured up to 5 days. An average of 3.44 +/- 0.28 x 10(11) platelets were collected in a product volume of 351 +/- 21 mL. Plasma removal resulted in a mean platelet loss of 7.8%. After PCT, a progressive decrease in platelet function was observed. LDH level rose through storage (171 +/- 81 U/L) to levels approximating LDH levels observed post-collection (180 +/- 103 U/L). There was a gradual decrease of the platelets to respond to hypotonic shock response from 90 +/- 9 % post-plasma reduction to 48 +/- 16% at day 5. All PLT units met the European requirements for leukoreduction and the pH limit of 6.8 up to day 5 post-collection. The new preparation set was capable of producing platelet units meeting the requirements for PCT. Despite differences observed in in vitro platelet function parameters, PLTs at storage day 5 fit the German and European guidelines.

A Human Platelet Calcium Calculator Trained by Pairwise Agonist Scanning

PubMed Central

Lee, Mei Yan; Diamond, Scott L.

2015-01-01

Since platelet intracellular calcium mobilization [Ca(t)]i controls granule release, cyclooxygenase-1 and integrin activation, and phosphatidylserine exposure, blood clotting simulations require prediction of platelet [Ca(t)]i in response to combinatorial agonists. Pairwise Agonist Scanning (PAS) deployed all single and pairwise combinations of six agonists (ADP, convulxin, thrombin, U46619, iloprost and GSNO used at 0.1, 1, and 10xEC50; 154 conditions including a null condition) to stimulate platelet P2Y1/P2Y12 GPVI, PAR1/PAR4, TP, IP receptors, and guanylate cyclase, respectively, in Factor Xa-inhibited (250 nM apixaban), diluted platelet rich plasma that had been loaded with the calcium dye Fluo-4 NW. PAS of 10 healthy donors provided [Ca(t)]i data for training 10 neural networks (NN, 2-layer/12-nodes) per donor. Trinary stimulations were then conducted at all 0.1x and 1xEC50 doses (160 conditions) as was a sampling of 45 higher ordered combinations (four to six agonists). The NN-ensemble average was a calcium calculator that accurately predicted [Ca (t)]i beyond the single and binary training set for trinary stimulations (R = 0.924). The 160 trinary synergy scores, a normalized metric of signaling crosstalk, were also well predicted (R = 0.850) as were the calcium dynamics (R = 0.871) and high-dimensional synergy scores (R = 0.695) for the 45 higher ordered conditions. The calculator even predicted sequential addition experiments (n = 54 conditions, R = 0.921). NN-ensemble is a fast calcium calculator, ideal for multiscale clotting simulations that include spatiotemporal concentrations of ADP, collagen, thrombin, thromboxane, prostacyclin, and nitric oxide. PMID:25723389

Bacterial contamination of platelet components not detected by BacT/ALERT®.

PubMed

Abela, M A; Fenning, S; Maguire, K A; Morris, K G

2018-02-01

To investigate the possible causes for false negative results in BacT/ALERT ® 3D Signature System despite bacterial contamination of platelet units. The Northern Ireland Blood Transfusion Service (NIBTS) routinely extends platelet component shelf life to 7 days. Components are sampled and screened for bacterial contamination using an automated microbial detection system, the BacT/ALERT ® 3D Signature System. We report on three platelet components with confirmed bacterial contamination, which represent false negative BacT/ALERT ® results and near-miss serious adverse events. NIBTS protocols for risk reduction of bacterial contamination of platelet components are described. The methodology for bacterial detection using BacT/ALERT ® is outlined. Laboratory tests, relevant patient details and relevant follow-up information are analysed. In all three cases, Staphylococcus aureus was isolated from the platelet residue and confirmed on terminal sub-culture using BacT/ALERT ® . In two cases, S. aureus with similar genetic makeup was isolated from the donors. Risk reduction measures for bacterial contamination of platelet components are not always effective. Automated bacterial culture detection does not eliminate the risk of bacterial contamination. Visual inspection of platelet components prior to release, issue and administration remains an important last line of defence. © 2017 British Blood Transfusion Society.

Human platelet lysate: Replacing fetal bovine serum as a gold standard for human cell propagation?

PubMed

Burnouf, Thierry; Strunk, Dirk; Koh, Mickey B C; Schallmoser, Katharina

2016-01-01

The essential physiological role of platelets in wound healing and tissue repair builds the rationale for the use of human platelet derivatives in regenerative medicine. Abundant growth factors and cytokines stored in platelet granules can be naturally released by thrombin activation and clotting or artificially by freeze/thaw-mediated platelet lysis, sonication or chemical treatment. Human platelet lysate prepared by the various release strategies has been established as a suitable alternative to fetal bovine serum as culture medium supplement, enabling efficient propagation of human cells under animal serum-free conditions for a multiplicity of applications in advanced somatic cell therapy and tissue engineering. The rapidly increasing number of studies using platelet derived products for inducing human cell proliferation and differentiation has also uncovered a considerable variability of human platelet lysate preparations which limits comparability of results. The main variations discussed herein encompass aspects of donor selection, preparation of the starting material, the possibility for pooling in plasma or additive solution, the implementation of pathogen inactivation and consideration of ABO blood groups, all of which can influence applicability. This review outlines the current knowledge about human platelet lysate as a powerful additive for human cell propagation and highlights its role as a prevailing supplement for human cell culture capable to replace animal serum in a growing spectrum of applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

Matrix metalloproteinase content and activity in low-platelet, low-leukocyte and high-platelet, high-leukocyte platelet rich plasma (PRP) and the biologic response to PRP by human ligament fibroblasts.

PubMed

Pifer, Matthew A; Maerz, Tristan; Baker, Kevin C; Anderson, Kyle

2014-05-01

Recent work has shown the presence of catabolic cytokines in platelet-rich plasma (PRP), but little is known about endogenous catabolic proteases such as matrix metalloproteinases (MMPs). Hypothesis/ To quantify MMP content in 2 commercially available PRP preparation systems: Arthrex Double Syringe System autologous conditioned plasma (ACP) and Biomet GPS (GPS). The hypothesis was that MMPs are actively secreted from PRP immediately after preparation. Controlled laboratory study. PRP was prepared using either ACP (low platelet, low leukocyte) or GPS (high platelet, high leukocyte). MMP-2, MMP-3, and MMP-9 concentrations were measured using multiplex enzyme-linked immunosorbent assays for up to 6 days in 2 donors, and MMP activity was measured in 3 donors using kinetic activity kits able to detect the enzymatic cleavage of a fluorogenic peptide. Human ligament fibroblasts were cultured and exposed to both ACP and GPS from 1 donor each. MMP-2, -3, and -9 concentrations were assayed in culture media at 24 and 48 hours after exposure. GPS exhibited higher total MMP-2, -3, and -9 concentrations for up to 144 hours of release, while ACP had higher platelet-normalized MMP-2 and MMP-3 concentrations. GPS had significantly higher total and endogenous MMP-2 activity (P = .004 and .014, respectively), MMP-3 activity (P = .020 and .015, respectively), and MMP-9 activity (P = .004 and .002, respectively) compared with ACP. Once normalized to platelet count, differences in MMP activity were not significant between ACP and GPS. Compared with controls, cells stimulated with interleukin-1 beta (IL-1β) and treated with ACP showed significantly higher fold changes of MMP-2 (P = .001) and MMP-3 (P = .003) concentrations at 24 hours than did cells treated with GPS. Total MMP-9 content was higher in the media of GPS-treated, IL-1β-stimulated cells compared with ACP-treated cells (P = .001). At 48 hours, IL-1β-stimulated cells treated with GPS exhibited higher fold changes of MMP-2 concentration (P = .002) compared with controls, but no difference in MMP-3 concentration was found. At 48 hours, there was a significantly higher concentration of MMP-9 in the cell culture media of ACP-treated cells compared with GPS-treated cells (P = .003). PRP prepared as both ACP and GPS contains MMP-2, -3, and -9, which is released over a period of at least 6 days. Furthermore, a large proportion of these MMPs are in their active form, and MMP activity is dependent on platelet count within the PRP preparation. Once exposed to ligament fibroblasts, both ACP and GPS cause the fibroblasts to release MMPs, most notably 24 hours after PRP exposure, and this release is dependent on prior IL-1β stimulation. The results of this study demonstrate that PRP therapy delivers ng/mL-range concentrations of catabolic proteases, which could perpetuate inflammation and inhibit tissue healing.

Acute myeloid leukemia developing in a granulocyte colony-stimulating factor-mobilized stem cell donor: A case report and review of the literature.

PubMed

Haddad, Housam; Wungjiranirun, Manida; Gergis, Usama

2016-09-01

We describe the first case of a FLT-3 mutated AML in a healthy donor, 3years after recombinant human granulocyte colony stimulating factor (rhG-CSF)-mobilized peripheral blood stem cell (PBSC) harvest. The patient had a myeloablative (MA) matched unrelated donor (MUD) stem cell transplant (SCT) for refractory AML. However, he experienced a secondary graft failure. He had a second non myeloablative (NMA) on day +75 from a second MUD. He achieved a complete neutrophil and platelet engraftment. After 4years of follow up, he is alive in complete remission with full second donor chimerism. Copyright © 2015 King Faisal Specialist Hospital & Research Centre. Published by Elsevier Ltd. All rights reserved.

Postoperative Decrease in Platelet Counts Is Associated with Delayed Liver Function Recovery and Complications after Partial Hepatectomy.

PubMed

Takahashi, Kazuhiro; Kurokawa, Tomohiro; Oshiro, Yukio; Fukunaga, Kiyoshi; Sakashita, Shingo; Ohkohchi, Nobuhiro

2016-05-01

Peripheral platelet counts decrease after partial hepatectomy; however, the implications of this phenomenon are unclear. We assessed if the observed decrease in platelet counts was associated with postoperative liver function and morbidity (complications grade ≤ II according to the Clavien-Dindo classification). We enrolled 216 consecutive patients who underwent partial hepatectomy for primary liver cancers, metastatic liver cancers, benign tumors, and donor hepatectomy. We classified patients as either low or high platelet percentage (postoperative platelet count/preoperative platelet count) using the optimal cutoff value calculated by a receiver operating characteristic (ROC) curve analysis, and analyzed risk factors for delayed liver functional recovery and morbidity after hepatectomy. Delayed liver function recovery and morbidity were significantly correlated with the lowest value of platelet percentage based on ROC analysis. Using a cutoff value of 60% acquired by ROC analysis, univariate and multivariate analysis determined that postoperative lowest platelet percentage ≤ 60% was identified as an independent risk factor of delayed liver function recovery (odds ratio (OR) 6.85; P < 0.01) and morbidity (OR, 4.90; P < 0.01). Furthermore, patients with the lowest platelet percentage ≤ 60% had decreased postoperative prothrombin time ratio and serum albumin level and increased serum bilirubin level when compared with patients with platelet percentage ≥ 61%. A greater than 40% decrease in platelet count after partial hepatectomy was an independent risk factor for delayed liver function recovery and postoperative morbidity. In conclusion, the decrease in platelet counts is an early marker to predict the liver function recovery and complications after hepatectomy.

Neonatal alloimmune thrombocytopenia due to anti-human leukocyte antigen antibody: a case report.

PubMed

Sasaki, M; Yagihashi, A; Kobayashi, D; Watanabe, N; Fujikawa, T; Chiba, S; Sato, S; Morishita, K; Sekimoto, T; Ikeda, H

2001-12-01

Anti-HLA antibodies reportedly exist in 31% of pregnant women. However, few ocurrences of neonatal alloimmune thrombocytopenia (NAIT) caused by anti-HLA antibody have been reported. In this study, maternal anti-HLA B60 and B61 antibodies were identified in patient serum at birth, but no anti-platelet antibodies were present. No maternal anti-HLA A2, A24, B51, or B52 antibodies were detected in patient serum. Platelet transfusion from the third donor was effective because these platelets expressed HLA A24 and B52 but not B60 or B61. Cross-matching tests between patient leukocytes or platelets and maternal serum were strongly positive, indicating that maternal anti-HLA antibodies were responsible for NAIT. This report is the first to demonstrate NAIT probably caused by maternal anti-HLA A24 and B52.

Platelet-rich plasma-containing fragmin-protamine micro-nanoparticles promote epithelialization and angiogenesis in split-thickness skin graft donor sites.

PubMed

Takabayashi, Yuki; Ishihara, Masayuki; Sumi, Yuki; Takikawa, Makoto; Nakamura, Shingo; Kiyosawa, Tomoharu

2015-01-01

Platelet-rich plasma (PRP) contains multiple growth factors, and fragmin-protamine micro-nanoparticles (F-P M-NPs) significantly enhance and stabilize growth factors. The purpose of this study was to evaluate the effects of PRP-containing F-P M-NPs (PRP&F-P M-NPs) on wound repair in split-thickness skin graft (STSG-) donor sites (DS). A total of 56 inbred male rats were anesthetized and split-thickness skin graft donor site (STSG-DS) were created with a Padgett dermatome. PRP&F-P M-NPs, F-P M-NPs, PRP, and saline (control) were then intradermally injected evenly into the STSG-DSs. On 3, 4, 5, 7, and 10 d after creation of STSG-DS, skin sample sections were stained with hematoxylin and eosin to evaluate reepithelialization and angiogenesis. Treatment of STSG-DS with PRP&F-P M-NPs effectively promoted epithelialization and new vessel formation compared with those treated with PRP, F-P M-NPs, and control (saline). The intradermal injection of PRP&F-P M-NPs promotes epithelialization and angiogenesis in STSG-DS wounds. Copyright © 2015 Elsevier Inc. All rights reserved.

Platelet transfusion refractoriness attributable to HLA antibodies produced by donor-derived cells after allogeneic bone marrow transplantation from one HLA-antigen-mismatched mother.

PubMed

Hatakeyama, Naoki; Hori, Tsukasa; Yamamoto, Masaki; Inazawa, Natsuko; Iesato, Kotoe; Miyazaki, Toru; Ikeda, Hisami; Tsutsumi, Hiroyuki; Suzuki, Nobuhiro

2011-12-01

PTR is a serious problem in patients being treated for hematologic disorders. Two patients with acute leukemia developed PTR after allogeneic BMT from one HLA-antigen-mismatched mother attributable to HLA antibodies, which could not be detected in their serum before BMT. HLA antibodies, whose specificity resembled that of each patient, were detected in each donor's serum. Each donor had probably been immunized during pregnancy by their partner's HLA antigens expressed by the fetus, consequently, transplanted donor-derived cells provoked HLA antibodies in each recipient early after BMT, and those HLA antibodies induced PTR. If the mothers are selected as donors for their children, they should be tested for the presence of HLA antibodies. © 2010 John Wiley & Sons A/S.

Effects of clopidogrel and aspirin in combination versus aspirin alone on platelet activation and major receptor expression in diabetic patients: the PLavix Use for Treatment Of Diabetes (PLUTO-Diabetes) trial.

PubMed

Serebruany, Victor L; Malinin, Alex I; Pokov, Alex; Barsness, Gregory; Hanley, Dan F

2008-01-01

Clopidogrel is widely used in diabetic patients after vascular events; however, the ability of this thienopyridine to yield additional antiplatelet protection on top of aspirin has never been explored in a controlled study with comprehensive assessment of platelet activity. The objective of this study was to compare the antiplatelet profiles of clopidogrel + aspirin in combination (C + ASA) versus aspirin alone (ASA) in patients with type 2 diabetes mellitus. Seventy patients with documented diabetes already treated with antecedent aspirin were randomly assigned to receive C + ASA or ASA in the PLUTO-Diabetes trial. Platelet studies included adenosine diphosphate-, collagen-, and arachidonic acid-induced aggregometry; PFA-100 (Dade-Behring, Miami, FL) and Ultegra (Accumetrics, San Diego, CA) analyzers; and expression of 6 major receptors by flow cytometry at baseline and at day 30 after randomization. There were no differences in the baseline clinical and platelet characteristics between the C + ASA and ASA groups, or subsequent significant changes in platelet biomarkers in the ASA group, except for diminished collagen-induced aggregation (P = .02). In contrast, when compared with the ASA group, therapy with C + ASA resulted in significant inhibition of platelet activity assessed by adenosine diphosphate aggregation (P = .0001); closure time prolongation (P = .0003) and reduction of platelet activation units with Ultegra (P = .0001); and expression of platelet/endothelial cell adhesion molecule 1 (P = .002), glycoprotein IIb/IIIa antigen (P = .0002), and activity (P = .0001). Treatment with C + ASA for 1 month provides significantly greater inhibition of platelet activity than ASA alone in diabetic patients in this small randomized trial. However, despite dual antiplatelet regimen, diabetic patients exhibit high residual activity of some platelet biomarkers, including unaffected protease-activated receptor 1 receptor expression.

Platelet reactivity in response to loading dose of atorvastatin or rosuvastatin in patients with stable coronary disease before percutaneous coronary intervention: The STATIPLAT randomized study.

PubMed

Godino, Cosmo; Pavon, Anna Giulia; Mangieri, Antonio; Salerno, Anna; Cera, Michela; Monello, Alberto; Chieffo, Alaide; Magni, Valeria; Cappelletti, Alberto; Margonato, Alberto; Colombo, Antonio

2017-08-01

The acute effects of statin loading dose (LD) on platelet reactivity in patients with chronic stable angina (CSA) are not completely clear. We hypothesized that LDs of atorvastatin and rosuvastatin have different pharmacodynamic acute effects on platelet aggregability in CSA patients with baseline normal platelet reactivity while on dual antiplatelet therapy (DAPT). From September 2011 to February 2014, all consecutive CSA patients on chronic DAPT (aspirin and clopidogrel) were evaluated before elective percutaneous coronary intervention (PCI). An initial assessment of platelet reactivity in response to thrombin receptor agonist, ADP, and ASP (respectively, indicative of the response to clopidogrel and aspirin) was performed with impedance aggregometry. Patients with high platelet reactivity to ADP test (area under the curve >47) were excluded. The remaining patients were randomized into 3 treatment groups: Group A, atorvastatin LD 80 mg; Group B, rosuvastatin LD 40 mg; and Group C, no statin LD (control group). A second assessment of platelet reactivity was performed ≥12 hours after statin LD. 682 patients were screened and 145 were randomized into the 3 groups. At baseline and after statin LD, no significant difference was found in platelet reactivity in response to 3 different agonists between the 3 groups. Subgroup analysis showed that platelet reactivity to ADP test was significantly lower in patients chronically treated with low-dose statins (n = 94) compared with statin-naïve patients (n = 51; 15.32 ± 1.50 vs 18.59 ± 1.30; P = 0.007). Loading dose of atorvastatin (80 mg) or rosuvastatin (40 mg) did not induce significant variation in platelet reactivity in CSA patients with baseline reduced platelet reactivity as in chronic DAPT. Our data confirm that chronic concomitant treatment with low-dose statins and clopidogrel resulted in significantly lower platelet reactivity compared with clopidogrel alone. © 2017 Wiley Periodicals, Inc.

Randomized controlled trial comparing impact on platelet reactivity of twice-daily with once-daily aspirin in people with Type 2 diabetes.

PubMed

Bethel, M A; Harrison, P; Sourij, H; Sun, Y; Tucker, L; Kennedy, I; White, S; Hill, L; Oulhaj, A; Coleman, R L; Holman, R R

2016-02-01

Reduced aspirin efficacy has been demonstrated in people with Type 2 diabetes. Because increased platelet reactivity and/or turnover are postulated mechanisms, we examined whether higher and/or more frequent aspirin dosing might reduce platelet reactivity more effectively. Participants with Type 2 diabetes (n = 24) but without known cardiovascular disease were randomized in a three-way crossover design to 2-week treatment periods with aspirin 100 mg once daily, 200 mg once daily or 100 mg twice daily. The primary outcome was platelet reactivity, assessed using the VerifyNow(™) ASA method. Relationships between platelet reactivity and aspirin dosing were examined using generalized linear mixed models with random subject effects. Platelet reactivity decreased from baseline with all doses of aspirin. Modelled platelet reactivity was more effectively reduced with aspirin 100 mg twice daily vs. 100 mg once daily, but not vs. 200 mg once daily. Aspirin 200 mg once daily did not differ from 100 mg once daily. Aspirin 100 mg twice daily was also more effective than once daily as measured by collagen/epinephrine-stimulated platelet aggregation and urinary thromboxane levels, with a similar trend measured by serum thromboxane levels. No episodes of bleeding occurred. In Type 2 diabetes, aspirin 100 mg twice daily reduced platelet reactivity more effectively than 100 mg once daily, and numerically more than 200 mg once daily. Clinical outcome trials evaluating primary cardiovascular disease prevention with aspirin in Type 2 diabetes may need to consider using a more frequent dosing schedule. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

Severe platelet dysfunction in NHL patients receiving ibrutinib is absent in patients receiving acalabrutinib

PubMed Central

Bye, Alexander P.; Unsworth, Amanda J.; Desborough, Michael J.; Hildyard, Catherine A. T.; Appleby, Niamh; Bruce, David; Kriek, Neline; Nock, Sophie H.; Sage, Tanya; Hughes, Craig E.

2017-01-01

The Bruton tyrosine kinase (Btk) inhibitor ibrutinib induces platelet dysfunction and causes increased risk of bleeding. Off-target inhibition of Tec is believed to contribute to platelet dysfunction and other side effects of ibrutinib. The second-generation Btk inhibitor acalabrutinib was developed with improved specificity for Btk over Tec. We investigated platelet function in patients with non-Hodgkin lymphoma (NHL) receiving ibrutinib or acalabrutinib by aggregometry and by measuring thrombus formation on collagen under arterial shear. Both patient groups had similarly dysfunctional aggregation responses to collagen and collagen-related peptide, and comparison with mechanistic experiments in which platelets from healthy donors were treated with the Btk inhibitors suggested that both drugs inhibit platelet Btk and Tec at physiological concentrations. Only ibrutinib caused dysfunctional thrombus formation, whereas size and morphology of thrombi following acalabrutinib treatment were of normal size and morphology. We found that ibrutinib but not acalabrutinib inhibited Src family kinases, which have a critical role in platelet adhesion to collagen that is likely to underpin unstable thrombus formation observed in ibrutinib patients. We found that platelet function was enhanced by increasing levels of von Willebrand factor (VWF) and factor VIII (FVIII) ex vivo by addition of intermediate purity FVIII (Haemate P) to blood from patients, resulting in consistently larger thrombi. We conclude that acalabrutinib avoids major platelet dysfunction associated with ibrutinib therapy, and platelet function may be enhanced in patients with B-cell NHL by increasing plasma VWF and FVIII. PMID:29296914

Functional display of platelet-binding VWF fragments on filamentous bacteriophage.

PubMed

Yee, Andrew; Tan, Fen-Lai; Ginsburg, David

2013-01-01

von Willebrand factor (VWF) tethers platelets to sites of vascular injury via interaction with the platelet surface receptor, GPIb. To further define the VWF sequences required for VWF-platelet interaction, a phage library displaying random VWF protein fragments was screened against formalin-fixed platelets. After 3 rounds of affinity selection, DNA sequencing of platelet-bound clones identified VWF peptides mapping exclusively to the A1 domain. Aligning these sequences defined a minimal, overlapping segment spanning P1254-A1461, which encompasses the C1272-C1458 cystine loop. Analysis of phage carrying a mutated A1 segment (C1272/1458A) confirmed the requirement of the cystine loop for optimal binding. Four rounds of affinity maturation of a randomly mutagenized A1 phage library identified 10 and 14 unique mutants associated with enhanced platelet binding in the presence and absence of botrocetin, respectively, with 2 mutants (S1370G and I1372V) common to both conditions. These results demonstrate the utility of filamentous phage for studying VWF protein structure-function and identify a minimal, contiguous peptide that bind to formalin-fixed platelets, confirming the importance of the VWF A1 domain with no evidence for another independently platelet-binding segment within VWF. These findings also point to key structural elements within the A1 domain that regulate VWF-platelet adhesion.

Mechanical circulatory support is associated with loss of platelet receptors glycoprotein Ibα and glycoprotein VI.

PubMed

Lukito, P; Wong, A; Jing, J; Arthur, J F; Marasco, S F; Murphy, D A; Bergin, P J; Shaw, J A; Collecutt, M; Andrews, R K; Gardiner, E E; Davis, A K

2016-11-01

Essentials Relationship of acquired von Willebrand disease (VWD) and platelet dysfunction is explored. Patients with ventricular assist devices and on extracorporeal membrane oxygenation are investigated. Acquired VWD and platelet receptor shedding is demonstrated in the majority of patients. Loss of platelet adhesion receptors glycoprotein (GP) Ibα and GPVI may increase bleeding risk. Background Ventricular assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) are associated with bleeding that is not fully explained by anticoagulant or antiplatelet use. Exposure of platelets to elevated shear in vitro leads to increased shedding. Objectives To investigate whether loss of platelet receptors occurs in vivo, and the relationship with acquired von Willebrand syndrome (AVWS). Methods Platelet counts, coagulation tests and von Willebrand factor (VWF) analyses were performed on samples from 21 continuous flow VAD (CF-VAD), 20 ECMO, 12 heart failure and seven aortic stenosis patients. Levels of platelet receptors were measured by flow cytometry or ELISA. Results The loss of high molecular weight VWF multimers was observed in 18 of 19 CF-VAD and 14 of 20 ECMO patients, consistent with AVWS. Platelet receptor shedding was demonstrated by elevated soluble glycoprotein (GP) VI levels in plasma and significantly reduced surface GPIbα and GPVI levels in CF-VAD and ECMO patients as compared with healthy donors. Platelet receptor levels were also significantly reduced in heart failure patients. Conclusions These data link AVWS and increased platelet receptor shedding in patients with CF-VADs or ECMO for the first time. Loss of the platelet surface receptors GPIbα and GPVI in heart failure, CF-VAD and ECMO patients may contribute to ablated platelet adhesion/activation, and limit thrombus formation under high/pathologic shear conditions. © 2016 International Society on Thrombosis and Haemostasis.

A man-made disease: Fetal neonatal alloimmune thrombocytopenia due to incompatibility between oocyte donor and gestational mother.

PubMed

Barg, Assaf Arie; Ifrah, Aviya Dvir; Strauss, Tzipi; Simchen, Michal J; Orvieto, Raoul; Rosenberg, Nurit; Kenet, Gili

2017-08-01

The incompatibility causing fetal and neonatal alloimmune thrombocytopenia (FNAIT) results from a fetus inheriting a paternal human platelet antigen (HPA), which is different from the maternal HPA. We present a unique case of FNAIT in a pregnancy involving an oocyte recipient mother with Turner syndrome. This is the first report of FNAIT in which the suggested mechanism involves antibodies produced by a gestational mother against the incompatible HPA of the oocyte donor. © 2017 Wiley Periodicals, Inc.

Prevalence of bacterial contamination in platelet concentrates at the National Center of Blood Transfusion (Mexico).

PubMed

Ibáñez-Cervantes, G; Bello-López, J M; Fernández-Sánchez, V; Domínguez-Mendoza, C A; Acevedo-Alfaro, L I

2017-06-01

Most common bacterial sepsis associated with transfusion is caused by contaminated Platelet Concentrates (PC). The screening of PC to detect bacterial contamination is obligatory in Mexico, and it is carried out in quality control programs. In Mexico, the identification and molecular characterization of bacterial contaminants to detect contamination sources have not been implemented due to high costs; however, it is an actual current need. One hundred PC were randomly selected and microbiologically analyzed. This sample size corresponds to 1% of the PC obtained by the National Center of Blood Transfusion (NCBT) in Mexico City according to the Official Mexican Standard NOM-253-SSA1-2012. Additionally, molecular biology tests were implemented in order to identify the possible contamination sources. Nine of the 100 PC analyzed (9%) showed bacterial contamination; analysis of the nucleotide sequences revealed the presence of characteristic microbiota from donor skin and soil. Diverse clonal relationship between the strains was identified in Staphylococcus epidermidis. Detection of contaminants associated with environmental and skin flora, shows the need to implement measures in the process of disinfecting skin at the site of phlebotomy and cleaning each of the areas involved in blood collection. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

A novel assay for the detection of anti-human platelet antigen antibodies (HPA-1a) based on peptide aptamer technology

PubMed Central

Thibaut, Julien; Mérieux, Yves; Rigal, Dominique; Gillet, Germain

2012-01-01

Background Neonatal alloimmune thrombocytopenia is mostly due to the presence of maternal antibodies against the fetal platelet antigen HPA-1a on the platelet integrin GPIIb-IIIa. Accurate detection of anti-HPA-1a antibodies in the mother is, therefore, critical. Current diagnostic assays rely on the availability of pools of human platelets that vary according to donors and blood centers. There is still no satisfactory standardization of these assays. Design and Methods Peptide aptamer was used to detect and identify HPA-1a-specific antibodies in human serum that do not require human platelets. A peptide aptamer library was screened using an anti-HPA-1a human monoclonal antibody as a bait to isolate an aptamer that mimics the human platelet antigen HPA-1a. Results This is the first report in platelet immunology of the use of a peptide aptamer for diagnostic purposes. This assay gives better results than the MAIPA currently in use, detecting around 90% of the expected alloantibodies. Conclusions This assay could help define a standard for the quantitation of anti-HPA antibodies. This report also demonstrates that peptide aptamers can potentially detect a variety of biomarkers in body fluids; this is of particular interest for diagnostic purposes. PMID:22133781

Metabolic plasticity in resting and thrombin activated platelets.

PubMed

Ravi, Saranya; Chacko, Balu; Sawada, Hirotaka; Kramer, Philip A; Johnson, Michelle S; Benavides, Gloria A; O'Donnell, Valerie; Marques, Marisa B; Darley-Usmar, Victor M

2015-01-01

Platelet thrombus formation includes several integrated processes involving aggregation, secretion of granules, release of arachidonic acid and clot retraction, but it is not clear which metabolic fuels are required to support these events. We hypothesized that there is flexibility in the fuels that can be utilized to serve the energetic and metabolic needs for resting and thrombin-dependent platelet aggregation. Using platelets from healthy human donors, we found that there was a rapid thrombin-dependent increase in oxidative phosphorylation which required both glutamine and fatty acids but not glucose. Inhibition of fatty acid oxidation or glutamine utilization could be compensated for by increased glycolytic flux. No evidence for significant mitochondrial dysfunction was found, and ATP/ADP ratios were maintained following the addition of thrombin, indicating the presence of functional and active mitochondrial oxidative phosphorylation during the early stages of aggregation. Interestingly, inhibition of fatty acid oxidation and glutaminolysis alone or in combination is not sufficient to prevent platelet aggregation, due to compensation from glycolysis, whereas inhibitors of glycolysis inhibited aggregation approximately 50%. The combined effects of inhibitors of glycolysis and oxidative phosphorylation were synergistic in the inhibition of platelet aggregation. In summary, both glycolysis and oxidative phosphorylation contribute to platelet metabolism in the resting and activated state, with fatty acid oxidation and to a smaller extent glutaminolysis contributing to the increased energy demand.

Dabigatran affects thrombin-dependent platelet aggregation after a week-long therapy.

PubMed

Sokol, Juraj; Nehaj, Frantisek; Ivankova, Jela; Mokan, Michal; Mokan, Marian; Stasko, Jan

2018-05-29

Dabigatran is a direct thrombin inhibitor. As the main adverse event is bleeding, it is relevant whether dabigatran has additional effects on platelet function. If so, it could affect the bleeding risk. We aimed to assess in vitro aggregation in patients with atrial fibrillation (AF) receiving dabigatran. We evaluated 32 AF patients treated with dabigatran (study group) and 18 non-anticoagulated non-AF blood donors (control group). We assessed light transmittance platelet aggregation (LTA) with 100 nmol/L γ-thrombin in both groups. The LTA was performed at two time-points in our dabigatran group of patients. The thrombin-induced platelet aggregation was significantly lower two hours after dabigatran was taken compared to baseline measurement (9% ± 6% vs. 29% ± 21%) in our study group. Moreover, we observed that the baseline value of platelet aggregation in patients on dabigatran treatment was significantly lower compared to healthy volunteers (29% ± 21% vs. 89 ± 8). However, one subanalysis showed that this significant reduction in platelet aggregation at baseline was only observed in patients who received dabigatran for over a week. The thrombin-induced platelet aggregation is reduced in non-valvular AF patients receiving dabigatran after a week-long therapy.

Impact of Intravenous Lysine Acetylsalicylate Versus Oral Aspirin on Prasugrel-Inhibited Platelets: Results of a Prospective, Randomized, Crossover Study (the ECCLIPSE Trial).

PubMed

Vivas, David; Martín, Agustín; Bernardo, Esther; Ortega-Pozzi, María Aranzazu; Tirado, Gabriela; Fernández, Cristina; Vilacosta, Isidre; Núñez-Gil, Iván; Macaya, Carlos; Fernández-Ortiz, Antonio

2015-05-01

Prasugrel and ticagrelor, new P2Y12-adenosine diphosphate receptor antagonists, are associated with greater pharmacodynamic inhibition and reduction of cardiovascular events compared with clopidogrel in patients with an acute coronary syndrome. However, evidence is lacking about the effects of achieving faster and stronger cyclooxygenase inhibition with intravenous lysine acetylsalicylate (LA) compared with oral aspirin on prasugrel-inhibited platelets. This was a prospective, randomized, single-center, open, 2-period crossover platelet function study conducted in 30 healthy volunteers. Subjects were randomly assigned to receive a loading dose of intravenous LA 450 mg plus oral prasugrel 60 mg or loading dose of aspirin 300 mg plus prasugrel 60 mg orally in a crossover fashion after a 2-week washout period between treatments. Platelet function was evaluated at baseline, 30 minutes, 1 h, 4 h, and 24 h using light transmission aggregometry and vasodilator-stimulated phosphoprotein phosphorylation. The primary end point of the study, inhibition of platelet aggregation after arachidonic acid 1.5 mmol/L at 30 minutes, was significantly higher in subjects treated with LA compared with aspirin: 85.3% versus 44.3%, respectively, P=0.003. This differential effect was observed at 1 hour (P=0.002) and 4 hours (P=0.048), but not at 24 hours. Subjects treated with LA presented less variability and faster and greater inhibition of platelet aggregation with arachidonic acid compared with aspirin. The administration of intravenous LA resulted in a significant reduction of platelet reactivity compared with oral aspirin on prasugrel-inhibited platelets. Loading dose of LA achieves an earlier platelet inhibition and with less variability than aspirin. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02243137. © 2015 American Heart Association, Inc.

On-pump Cardiac Surgery Enhances Platelet Renewal and Impairs Aspirin Pharmacodynamics: Effects of Improved Dosing Regimens.

PubMed

Cavalca, V; Rocca, B; Veglia, F; Petrucci, G; Porro, B; Myasoedova, V; De Cristofaro, R; Turnu, L; Bonomi, A; Songia, P; Cavallotti, L; Zanobini, M; Camera, M; Alamanni, F; Parolari, A; Patrono, C; Tremoli, E

2017-11-01

On-pump cardiac surgery may trigger inflammation and accelerate platelet cyclooxygenase-1 renewal, thereby modifying low-dose aspirin pharmacodynamics. Thirty-seven patients on standard aspirin 100 mg once-daily were studied before surgery and randomized within 36 hours postsurgery to 100 mg once-daily, 100 mg twice-daily, or 200 mg once-daily for 90 days. On day 7 postsurgery, immature and mature platelets, platelet mass, thrombopoietin, glycocalicin, leukocytes, C-reactive protein, and interleukin-6 significantly increased. Interleukin-6 significantly correlated with immature platelets. At day 7, patients randomized to 100 mg once-daily showed a significant increase in serum thromboxane (TX)B 2 within the 24-hour dosing interval and urinary TXA 2 metabolite (TXM) excretion. Aspirin 100 mg twice-daily lowered serum TXB 2 and prevented postsurgery TXM increase (P < 0.01), without affecting prostacyclin metabolite excretion. After cardiac surgery, shortening the dosing interval, but not doubling the once-daily dose, rescues the impaired antiplatelet effect of low-dose aspirin and prevents platelet activation associated with acute inflammation and enhanced platelet turnover. © 2017 American Society for Clinical Pharmacology and Therapeutics.

First comparative analysis concerning the plasma platelet contamination during MNC collection.

PubMed

Pfeiffer, Hella; Achenbach, Susanne; Strobel, Julian; Zimmermann, Robert; Eckstein, Reinhold; Strasser, Erwin F

2017-08-01

Monocytes can be cultured into dendritic cells with addition of autologous plasma, which is highly prone to platelet contamination due to the apheresis process. Since platelets affect the maturation process of monocytes into dendritic cells and might even lead to a diminished harvest of dendritic cells, it is very important to reduce the platelet contamination. A new collection device (Spectra Optia) was analyzed, compared to two established devices (COM.TEC, Cobe Spectra) and evaluated regarding the potential generation of source plasma. Concurrent plasma collected during leukapheresis was analyzed for residual cell contamination in a prospective study with the new Spectra Optia apheresis device (n=24) and was compared with COM.TEC and Cobe Spectra data (retrospective analysis, n=72). Donor pre-donation counts of platelets were analyzed for their predictive value of contaminating PLTs in plasma harvests. The newest apheresis device showed the lowest residual platelet count of the collected concurrent plasma (median 3.50×10 9 /l) independent of pre-donation counts. The other two devices and sets had a higher platelet contamination. The contamination of the plasma with leukocytes was very low (only 2.0% were higher than 0.5×10 9 /l). This study showed a significant reduction of platelet contamination of the concurrent plasma collected with the new Spectra Optia device. This plasma product with low residual platelets and leukocytes might also be used as plasma for fractionation. Copyright © 2017 Elsevier Ltd. All rights reserved.

A randomized comparison of platelet reactivity in patients after treatment with various commercial clopidogrel preparations: the CLO-CLO trial.

PubMed

Oberhänsli, Markus; Lehner, Cédric; Puricel, Serban; Lehmann, Sonja; Togni, Mario; Stauffer, Jean-Christophe; Baeriswyl, Gérard; Goy, Jean-Jacques; Cook, Stéphane

2012-11-01

The salt linked to the clopidogrel molecule in generic preparations is suspected to affect its clinical efficacy. There is a lack of information about inhibition of platelet reactivity by generic preparations. To compare the effect of original clopidogrel (clopidogrel bisulphate [Plavix(®)]), generic clopidogrel preparations (clopidogrel hydrochloride [Clopidogrel-Mepha(®)]; clopidogrel besylate [Clopidogrel Sandoz(®)]) and prasugrel (Efient(®)) on platelet reactivity in patients with coronary artery disease. Patients with coronary artery disease treated with stents received, in a random sequence, original clopidogrel bisulphate, clopidogrel hydrochloride and clopidogrel besylate. Platelet function was assessed with the Multiplate analyser after an initial loading dose (600 mg) and at day 10 after each treatment period. Prasugrel was given for another 10 days. An adenosine diphosphate (ADP) test value<46 antiaggregation units (U) was defined as therapeutic platelet inhibition. Sixty patients (mean age 69 ± 10 years; 50 men) were randomized. Original clopidogrel bisulphate, clopidogrel hydrochloride and clopidogrel besylate provided similar inhibition of platelet reactivity with values of 31 ± 25, 33 ± 28 and 28 ± 23 U, respectively (P not significant). Prasugrel provided better inhibition of platelet function (10 ± 11 vs. 31 ± 25 U for clopidogrel bisulphate; P<0.001). An ADP test value>46 U was measured in 11 patients (18%) with clopidogrel bisulphate, 13 (22%) with clopidogrel besylate and 13 (22%) with clopidogrel hydrochloride compared with only one (2%) with prasugrel. Generic clopidogrel preparations provided similar inhibition of platelet reactivity to original clopidogrel bisulphate, although prasugrel was more efficient. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Improved extension of platelet storage in a polyolefin container with higher oxygen permeability.

PubMed

Yuasa, Takeshi; Ohto, Hitoshi; Yasunaga, Reiko; Kai, Takanori; Shirahama, Noriaki; Ogata, Takashi

2004-07-01

This study evaluated a newly developed polyolefin bag, which has a 50%/m(2) higher oxygen permeability to extend the shelf-life of platelets. Single-donor aphaeresis platelets were pooled, separated equally into two bags, PO-80 (0.8 l capacity) and KBP-PO (1 l capacity) for control, and stored in plasma for up to 7 d. Platelet biochemical and functional parameters were monitored in bags containing high (4.2 x 10(11)/250 ml/bag, n = 9) and low (2.0 x 10(11)/200 ml/bag, n = 3) concentrations of platelets over the storage period. After 7 d of storage, the PO-80 bags containing high concentrations of platelets had a better pH (mean pH 6.74) than those stored in KBP-PO (pH 6.32, P < 0.01); none of the nine PO-80 bags with a high platelet concentration had a pH below 6.2, compared with four of nine controls (P < 0.05). Similarly, lactate values were 20.19 mmol/l and 28.09 mmol/l respectively (P < 0.05). Aerobic metabolism was maintained better with greater O(2) consumption and less lactate generation in high-platelet concentration PO-80 bags than in the control bags. A significant difference was also found in pH, pCO(2) and lactate levels between the two bags containing low concentrations of platelets during the 7-d period. The in vitro characteristics of platelets declined less over 7 d when stored in a higher oxygen permeable container than in a marketed bag.

Blood glucose regulation during living-donor liver transplant surgery.

PubMed

Gedik, Ender; İlksen Toprak, Hüseyin; Koca, Erdinç; Şahin, Taylan; Özgül, Ülkü; Ersoy, Mehmet Özcan

2015-04-01

The goal of this study was to compare the effects of 2 different regimens on blood glucose levels of living-donor liver transplant. The study participants were randomly allocated to the dextrose in water plus insulin infusion group (group 1, n = 60) or the dextrose in water infusion group (group 2, n = 60) using a sealed envelope technique. Blood glucose levels were measured 3 times during each phase. When the blood glucose level of a patient exceeded the target level, extra insulin was administered via a different intravenous route. The following patient and procedural characteristics were recorded: age, sex, height, weight, body mass index, end-stage liver disease, Model for End-Stage Liver Disease score, total anesthesia time, total surgical time, and number of patients who received an extra bolus of insulin. The following laboratory data were measured pre- and postoperatively: hemoglobin, hematocrit, platelet count, prothrombin time, international normalized ratio, potassium, creatinine, total bilirubin, and albumin. No hypoglycemia was noted. The recipients exhibited statistically significant differences in blood glucose levels during the dissection and neohepatic phases. Blood glucose levels at every time point were significantly different compared with the first dissection time point in group 1. Excluding the first and second anhepatic time points, blood glucose levels were significantly different as compared with the first dissection time point in group 2 (P < .05). We concluded that dextrose with water infusion alone may be more effective and result in safer blood glucose levels as compared with dextrose with water plus insulin infusion for living-donor liver transplant recipients. Exogenous continuous insulin administration may induce hyperglycemic attacks, especially during the neohepatic phase of living-donor liver transplant surgery. Further prospective studies that include homogeneous patient subgroups and diabetic recipients are needed to support the use of dextrose plus water infusion without insulin.

Probable transfusion-transmitted Zika virus in Brazil.

PubMed

Barjas-Castro, Maria L; Angerami, Rodrigo N; Cunha, Mariana S; Suzuki, Akemi; Nogueira, Juliana S; Rocco, Iray M; Maeda, Adriana Y; Vasami, Fernanda G S; Katz, Gizelda; Boin, Ilka F S F; Stucchi, Raquel S B; Resende, Mariângela R; Esposito, Danillo L A; de Souza, Renato P; da Fonseca, Benedito A; Addas-Carvalho, Marcelo

2016-07-01

Zika virus (ZIKV) is an emerging arthropod-borne flavivirus transmitted by Aedes mosquitoes. Recent commentaries regarding ZIKV routes of transmission describe a potential transmission by transfusion. Herein, we report a probable case of transfusion-transmitted ZIKV infection through a platelet transfusion that was detected from postdonation information. A blood donor made a voluntary telephone report to the blood donor facility 3 days after donation and informed the facility of a febrile illness (fever, malaise, and headaches). Due to the ongoing dengue epidemic, the initial clinical investigation included dengue among other possible diagnoses. The serology and molecular laboratory results excluded dengue infection. However, stored samples from the donation were positive for ZIKV on reverse transcription-polymerase chain reaction (RT-PCR) analysis. A retrospective investigation demonstrated that the platelet concentrate, which was part of a pool, had been transfused after a liver transplantation. A physician had evaluated the patient 4 days after surgery. Laboratory investigation showed enzyme-linked immunosorbent assay results that were negative for dengue immunoglobulin M antibodies; however, the results were positive for hemagglutination inhibition antibodies against flavivirus. ZIKV RT-PCR and virus isolation analyses in cell cultures from recipient serum were both positive. The sequencing confirmed ZIKV in the donor and patient samples. Ten partial nucleotide sequences from the ZIKV strain that were detected in the donor were aligned and compared with the ZIKV genome detected in the recipient, revealing a 99.8% homology between the two strains. This is a case of probable transmission of ZIKV through blood transfusion. The patient had been transfused with the blood product from an infected donor, most likely in the incubation period after ZIKV infection but prior to clinical disease onset. This report emphasizes the importance of postdonation information and recipient investigations during outbreaks of potentially blood-borne infections. © 2016 AABB.

Evaluation of the new continuous mononuclear cell collection protocol versus an older version on two different apheresis machines.

PubMed

Spoerl, Silvia; Wäscher, Dagmar; Nagel, Stefanie; Peschel, Christian; Verbeek, Mareike; Götze, Katharina; Krackhardt, Angela M

2018-05-06

Cell separators are routinely used to collect CD34 + blood stem cells in the context of customized stem cell transplantation procedures. The Spectra Optia (Terumo BCT) is a novel development of the precursor instrument, the Cobe Spectra (Terumo BCT). In this report, 146 autologous and 42 allogeneic donors undergoing apheresis on the Cobe Spectra using the mononuclear cell (MNC) program 4.7 or on the Spectra Optia using the new continuous mononuclear cell (cMNC) program 11.2 are compared. Viability of cells and collection efficacy within the apheresis products was comparable for autologous and allogeneic products collected with the MNC or cMNC method. However, we found a reduced duration of the apheresis procedure and lower hematocrit within the apheresis products when using the cMNC in autologous and allogeneic donors. Moreover, allogeneic donors collected substantially more CD34 + cells per kilogram of body weight when using the cMNC method. Differences in platelets before and after apheresis were substantially smaller in this cohort when compared to the cohort collected with the MNC method. Neutrophil and platelet engraftment after autologous or allogeneic transplantation with a product collected with the MNC procedure was comparable to a transplantation with a product processed according to the cMNC method. Comparison of the MNC (Cobe Spectra) and the cMNC (Spectra Optia) methods demonstrated an equal performance and outcome. However, advantages were present using the cMNC method with respect to apheresis duration and hematocrit within the apheresis product (autologous/allogeneic donors) and numbers of CD34 + cells collected, especially in allogeneic donors. © 2018 AABB.

Glaucocalyxin A Inhibits Platelet Activation and Thrombus Formation Preferentially via GPVI Signaling Pathway

PubMed Central

Li, Qiang; Ren, Lijie; Liu, Xiaohui; Chu, Chunjun; Ozaki, Yukio; Zhang, Jian; Zhu, Li

2013-01-01

Platelets play a pivotal role in atherothrombosis and the antiplatelet agents have been proved to be useful in preventing onset of acute clinical events including myocardial infarction and stroke. Increasing number of natural compounds has been identified to be potential antiplatelet agents. Here we report the antiplatelet effect of glaucocalyxin A (GLA), an ent-diterpenoid that we isolated and purified from the aerial parts of Rabdosia japonica (Burm. f.) var. glaucocalyx (Maxim.) Hara, and investigate the molecular mechanisms by which GLA inhibits platelet activation and thrombus formation. The effect of GLA on platelet activation was measured using platelets freshly isolated from peripheral blood of healthy donors. Results showed that pretreatment of human platelets with lower concentrations of GLA (0.01μg/ml, 0.1μg/ml) significantly inhibited platelet aggregation induced by collagen (P<0.001) and CRP (P<0.01), a synthetic GPVI ligand, but not by ADP and U46619. Accordingly, GLA inhibited collagen-stimulated tyrosine phosphorylation of Syk, LAT, and phospholipase Cγ2, the signaling events in collagen receptor GPⅥ pathway. GLA also inhibited platelet p-selectin secretion and integrin activation by convulxin, a GPVI selective ligand. Additionally, GLA was found to inhibit low-dose thrombin-induced platelet activation. Using a flow chamber device, GLA was found to attenuate platelet adhesion on collagen surfaces in high shear condition. In vivo studies showed that GLA administration increased the time for complete occlusion upon vascular injury in mice, but did not extend tail-bleeding time when mice were administered with relatively lower doses of GLA. Therefore, the present results provide the molecular basis for the inhibition effect of GLA on platelet activation and its in vivo effect on thrombus formation, suggesting that GLA could potentially be developed as an antiplatelet and antithrombotic agent. PMID:24386454

Nonthrombogenic Hydrogel Coatings with Carbene-Cross-Linking Bioadhesives.

PubMed

Nanda, Himansu Sekhar; Shah, Ankur Harish; Wicaksono, Gautama; Pokholenko, Oleksandr; Gao, Feng; Djordjevic, Ivan; Steele, Terry W J

2018-05-14

Bioadhesives are a current unmet clinical need for mending of blood contacting soft tissues without inducing thrombosis. Recent development of carbene precursor bioadhesives with the advantages of on-demand curing, tuneable modulus, and wet adhesion have been synthesized by grafting diazirine onto poly (amidoamine) (PAMAM-G5) dendrimers. Herein, the structure activity relationships of platelet adhesion and activation is evaluated for the first time on the cured PAMAM-g-diazirine bioadhesives. Three strategies were employed to prevent healthy human donor platelets from adhering and activating on light-cured bioadhesive surfaces: (1) Attenuation of cationic surface charge, (2) antifouling composites by incorporating heparin and alginate in uncured formulation, and (3) heparin wash of cured bioadhesive surface. Topographical imaging of cured and ethanol dehydrated bioadhesive surfaces was used to quantify the adhered and activated platelets with scanning electron microscopy, whose resolution allowed identification of round senescent, short dendritic, and long dendritic platelets. Cured surfaces of PAMAM-g-diazirine (15%) had 10300 ± 500 adhered platelets mm -2 with 99.7% activation into short/long dendritic cells. Reduction of primary amines by higher degree of diazirine grafting or capping of free amines by acetylation reduces platelet adherence (2400 ± 200 vs 3000 ± 300, respectively). Physical incorporation of heparin and alginate in the formulations reduced the activated platelet; 1300 ± 300 and 300 ± 50, activated platelets mm -2 , in comparison with additive free adhesive formulation. Similarly, heparin rinse of the surface of additive free bioadhesive reduced the activated platelet to platelets of heparin composites at 600 ± 100 platelets mm -2 . PAMAM-g-diazirine (15%) bioadhesive retained the photocured mechanical properties and lap shear adhesion despite the addition of heparin and alginate additives.

Early storage lesions in apheresis platelets are induced by the activation of the integrin αIIbβ₃ and focal adhesion signaling pathways.

PubMed

Thiele, Thomas; Iuga, Cristina; Janetzky, Susann; Schwertz, Hansjorg; Gesell Salazar, Manuela; Fürll, Birgit; Völker, Uwe; Greinacher, Andreas; Steil, Leif

2012-12-05

Production and storage of platelet concentrates (PC) induce protein changes in platelets leading to impaired platelet function. This study aimed to identify signaling pathways involved in the development of early platelet storage lesions in apheresis-PCs stored in plasma or additive solution (PAS). Apheresis-PCs from four donors were stored in plasma or in PAS at 22°C (n=4 each). Platelets were analyzed at day 0 (production day) and after 1, 6 and 9 days of storage. Platelet response to agonists (TRAP, collagen, ADP) and to hypotonic shock decreased, CD62P expression increased in both storage media over time. Using DIGE 1550 protein spots were monitored and compared to baseline values at day 0. Platelets in plasma displayed changes in 352 spots (166/day 1, 263/day 6 and 201/day 9); in PAS 325 spots changed (202/day 1, 221/day 6, 200/day 9). LC-ESI-MS/MS analysis of 405 platelet proteins revealed 32 proteins changed during storage in plasma (9/day 1, 15/day 6 and 26/day 9) and 28 in PAS (5/day 1, 20/day 6, 26/day 9). Ingenuity pathway analysis found integrin-αII(b)β(3) and focal adhesion signaling pathways involved in early alterations, being confirmed by Western blotting. Corresponding mRNAs in platelets were identified by next generation sequencing for 84 changed proteins. Integrin-αII(b)β(3) and focal adhesion signaling cause irreversible early storage lesions in apheresis platelets. This article is part of a Special Issue entitled: Integrated omics. Copyright © 2012 Elsevier B.V. All rights reserved.

Induced Pluripotent Stem Cell-Derived Red Blood Cells and Platelet Concentrates: From Bench to Bedside.

PubMed

Focosi, Daniele; Amabile, Giovanni

2017-12-27

Red blood cells and platelets are anucleate blood components indispensable for oxygen delivery and hemostasis, respectively. Derivation of these blood elements from induced pluripotent stem (iPS) cells has the potential to develop blood donor-independent and genetic manipulation-prone products to complement or replace current transfusion banking, also minimizing the risk of alloimmunization. While the production of erythrocytes from iPS cells has challenges to overcome, such as differentiation into adult-type phenotype that functions properly after transfusion, platelet products are qualitatively and quantitatively approaching a clinically-applicable level owing to advances in expandable megakaryocyte (MK) lines, platelet-producing bioreactors, and novel reagents. Guidelines that assure the quality of iPS cells-derived blood products for clinical application represent a novel challenge for regulatory agencies. Considering the minimal risk of tumorigenicity and the expected significant demand of such products, ex vivo production of iPS-derived blood components can pave the way for iPS translation into the clinic.

Platelet-, leucocyte- and red cell-derived microparticles in stored whole blood, with and without leucofiltration, with and without ionising radiation.

PubMed

Saito, Shunnichi; Nollet, Kenneth E; Ngoma, Alain M; Ono, Takako; Ohto, Hitoshi

2018-02-01

Storage lesion, including microparticle formation, has been partially characterised in whole blood, but not in all combinations of pre-storage leucofiltration and/or irradiation. Single-donor whole blood products were processed into four subunits: with and without leucofiltration, with and without X-irradiation (25 Gy). Platelet-, leucocyte-, and erythrocyte-derived microparticles and free haemoglobin were measured periodically throughout 42 days of storage. Pre-storage leucofiltration substantially reduced platelet- and leucocyte-derived microparticle counts throughout storage. Irradiation, in contrast, had no significant effect on microparticle counts. A gate for all microparticles showed a substantial time-dependent increase in unfiltered whole blood. A time-dependent increase in free haemoglobin was greatest in unfiltered, irradiated whole blood. This study indicates that leucofiltration can prevent the formation of leucocyte- and platelet-derived microparticles, and might reduce haemolysis in irradiated whole blood, either by removing factors that provoke haemolysis, or by selective retention of senescent or effete red cells most prone to haemolysis.

Analysis of vesicle fluid following the sting of the lionfish Pterois volitans.

PubMed

Auerbach, P S; McKinney, H E; Rees, R S; Heggers, J P

1987-01-01

Fluid aspirated from blisters following a lionfish (Pterois volitans) sting was analyzed utilizing combined capillary column gas chromatography and negative ion chemical ionization mass spectrometry. Analysis for prostaglandin F2 alpha demonstrated 16.91 ng/ml, for prostaglandin E2 0.143 ng/ml, for 6-keto-prostaglandin F1 alpha less than 0.1 ng/ml (nondetectable) and for thromboxane B2 1.65 ng/ml. Platelet aggregation studies showed that blister fluid caused aggregation of isolated platelets only, which was inhibited by heat treatment or by the presence of normal donor plasma.

Metformin reduces hyper-reactivity of platelets from patients with polycystic ovary syndrome by improving mitochondrial integrity.

PubMed

Randriamboavonjy, Voahanginirina; Mann, W Alexander; Elgheznawy, Amro; Popp, Rüdiger; Rogowski, Paul; Dornauf, Imke; Dröse, Stefan; Fleming, Ingrid

2015-08-31

Polycystic ovary syndrome (PCOS) is associated with decreased fertility, insulin resistance and an increased risk of developing cardiovascular disease. Treating PCOS patients with metformin improves fertility and decreases cardiovascular complications. Given that platelet activation contributes to both infertility and cardiovascular disease development, we assessed platelet reactivity in PCOS patients and the consequences of metformin treatment. Compared to washed platelets from healthy donors, platelets from PCOS patients demonstrated enhanced reactivity and impaired activation of the AMP-activated kinase (AMPK). PCOS platelets also demonstrated enhanced expression of mitochondrial proteins such as the cytochrome c reductase, ATP synthase and the voltage-dependent anion channel-1. However, mitochondrial function was impaired as demonstrated by a decreased respiration rate. In parallel, the phosphorylation of dynamin-related protein-1 (Drp-1) on Ser616 was increased while that on Ser637 decreased. The latter changes were accompanied by decreased mitochondrial size. In insulin-resistant PCOS patients (HOMA-IR> 2) metformin treatment (1.7 g per day for 4 weeks to 6 months) improved insulin sensitivity, restored mitochondrial integrity and function and normalised platelet aggregation. Treatment was without effect in PCOS patients with HOMA-IR< 2. Moreover, treatment of megakaryocytes with metformin enhanced mitochondrial content and in the same cells metformin enhanced the phosphorylation of the Drp-1 on Ser637 via an AMPKα1-dependent mechanism. In conclusion, the improvement of mitochondrial integrity and platelet reactivity may contribute to the beneficial effects of metformin on cardiovascular disease.

Platelet bioreactor: accelerated evolution of design and manufacture.

PubMed

Thon, Jonathan N; Dykstra, Brad J; Beaulieu, Lea M

2017-07-01

Platelets, responsible for clot formation and blood vessel repair, are produced by megakaryocytes in the bone marrow. Platelets are critical for hemostasis and wound healing, and are often provided following surgery, chemotherapy, and major trauma. Despite their importance, platelets today are derived exclusively from human volunteer donors. They have a shelf life of just five days, making platelet shortages common during long weekends, civic holidays, bad weather, and during major emergencies when platelets are needed most. Megakaryocytes in the bone marrow generate platelets by extruding long cytoplasmic extensions called proplatelets through gaps/fenestrations in blood vessels. Proplatelets serve as assembly lines for platelet production by sequentially releasing platelets and large discoid-shaped platelet intermediates called preplatelets into the circulation. Recent advances in platelet bioreactor development have aimed to mimic the key physiological characteristics of bone marrow, including extracellular matrix composition/stiffness, blood vessel architecture comprising tissue-specific microvascular endothelium, and shear stress. Nevertheless, how complex interactions within three-dimensional (3D) microenvironments regulate thrombopoiesis remains poorly understood, and the technical challenges associated with designing and manufacturing biomimetic microfluidic devices are often under-appreciated and under-reported. We have previously reviewed the major cell culture, platelet quality assessment, and regulatory roadblocks that must be overcome to make human platelet production possible for clinical use [1]. This review builds on our previous manuscript by: (1) detailing the historical evolution of platelet bioreactor design to recapitulate native platelet production ex vivo, and (2) identifying the associated challenges that still need to be addressed to further scale and validate these devices for commercial application. While platelets are among the first cells whose ex vivo production is spearheading major engineering advancements in microfluidic design, the resulting discoveries will undoubtedly extend to the production of other human tissues. This work is critical to identify the physiological characteristics of relevant 3D tissue-specific microenvironments that drive cell differentiation and elaborate upon how these are disrupted in disease. This is a burgeoning field whose future will define not only the ex vivo production of platelets and development of targeted therapies for thrombocytopenia, but the promise of regenerative medicine for the next century.

Effects of preoperative aspirin on perioperative platelet activation and dysfunction in patients undergoing off-pump coronary artery bypass graft surgery: A prospective randomized study.

PubMed

Lee, Jiwon; Jung, Chul-Woo; Jeon, Yunseok; Kim, Tae Kyong; Cho, Youn Joung; Koo, Chang-Hoon; Choi, Yoon Hyeong; Kim, Ki-Bong; Hwang, Ho Young; Kim, Hang-Rae; Park, Ji-Young

2017-01-01

The benefit of aspirin use after coronary artery bypass graft surgery has been well proven. However, the effect of preoperative aspirin use in patients undergoing off-pump coronary artery bypass graft surgery (OPCAB) has not been evaluated sufficiently. To evaluate platelet function changes during OPCAB due to preoperative aspirin use, we conducted a randomized controlled trial using flow cytometry and the Multiplate® analyzer. Forty-eight patients scheduled for elective OPCAB were randomized to the aspirin continuation (100 mg/day until operative day) and discontinuation (4 days before the operative day) groups. Platelet function was measured using the platelet activation markers CD62P, CD63, and PAC-1 by flow cytometry, and platelet aggregation was measured using the Multiplate® analyzer, after the induction of anesthesia (baseline), at the end of the operation, and 24 and 48 h postoperatively. Findings of conventional coagulation assays, thromboelastography by ROTEM® assays, and postoperative bleeding-related clinical outcomes were compared between groups. No significant change in CD62P, CD63, or PAC-1 was observed at the end of the operation or 24 or 48 h postoperatively compared with baseline in either group. The area under the curve for arachidonic acid-stimulated platelet aggregation, measured by the Multiplate® analyzer, was significantly smaller in the aspirin continuation group (P < 0.01). However, chest tube drainage and intraoperative and postoperative transfusion requirements did not differ between groups. Our study showed that preoperative use of aspirin for OPCAB did not affect perioperative platelet activation, but it impaired platelet aggregation, which did not affect postoperative bleeding, by arachidonic acid.

Effects of different concentrations of Platelet-rich Plasma and Platelet-Poor Plasma on vitality and differentiation of autologous Adipose tissue-derived stem cells.

PubMed

Felthaus, Oliver; Prantl, Lukas; Skaff-Schwarze, Mona; Klein, Silvan; Anker, Alexandra; Ranieri, Marco; Kuehlmann, Britta

2017-01-01

Autologous fat grafts and adipose-derived stem cells (ASCs) can be used to treat soft tissue defects. However, the results are inconsistent and sometimes comprise tissue resorption and necrosis. This might be due to insufficient vascularization. Platelet-rich plasma (PRP) is a source of concentrated autologous platelets. The growth factors and cytokines released by platelets can facilitate angiogenesis. The simultaneous use of PRP might improve the regeneration potential of fat grafts. The optimal ratio has yet to be elucidated. A byproduct of PRP preparation is platelet-poor plasma (PPP). In this study we investigated the influence of different concentrations of PRP on the vitality and differentiation of ASCs. We processed whole blood with the Arthrex Angel centrifuge and isolated ASCs from the same donor. We tested the effects of different PRP and PPP concentrations on the vitality using resazurin assays and the differentiation of ASCs using oil-red staining. Both cell vitality and adipogenic differentiation increase to a concentration of 10% to 20% PRP. With a PRP concentration of 30% cell vitality and differentiation decrease. Both PRP and PPP can be used to expand ASCs without xenogeneic additives in cell culture. A PRP concentration above 20% has inhibitory effects.

Release of Phosphorylated HSP27 (HSPB1) from Platelets Is Accompanied with the Acceleration of Aggregation in Diabetic Patients

PubMed Central

Tokuda, Haruhiko; Kuroyanagi, Gen; Tsujimoto, Masanori; Enomoto, Yukiko; Matsushima-Nishiwaki, Rie; Onuma, Takashi; Kojima, Akiko; Doi, Tomoaki; Tanabe, Kumiko; Akamatsu, Shigeru; Iida, Hiroki; Ogura, Shinji; Otsuka, Takanobu; Iwama, Toru; Tanikawa, Takahisa; Ishikawa, Kei; Kojima, Kumi; Kozawa, Osamu

2015-01-01

We investigated the relationship between HSP27 phosphorylation and collagen-stimulated activation of platelets in patients with diabetes mellitus (DM). Platelet-rich plasma was prepared from blood of type 2 DM patients. The platelet aggregation was analyzed in size of aggregates by an aggregometer using a laser scattering method. The protein phosphorylation was analyzed by Western blotting. Phosphorylated-HSP27 and PDGF-AB released from platelets were measured by ELISA. The phosphorylated-HSP27 levels at Ser-78 and Ser-82 induced by collagen were directly proportional to the platelet aggregation. Total HSP27 levels in platelets were decreased concomitantly with the phosphorylation. The released HSP27 levels were significantly correlated with the phosphorylated levels of HSP27 in the platelets stimulated by 0.3 μg/ml collagen. The low dose collagen-stimulated release of HSP27 was detected but relatively small in healthy donors. The released levels of PDGF-AB were in parallel with the levels of released HSP27. Area under the curve (AUC) of small aggregation (9-25 μm) induced by 0.3 μg/ml collagen was inversely proportional to the levels of released HSP27. AUC of large aggregation (50-70 μm) was directly proportional to the levels of released HSP27. Exogenous recombinant phosphorylated- HSP27 hardly affected the aggregation or the released levels of PDGF-AB induced by collagen. These results strongly suggest that HSP27 is released from human platelets accompanied with its phosphorylation induced by collagen, which is correlated with the acceleration of platelet aggregation in type 2 DM patients. PMID:26046355

Release of Phosphorylated HSP27 (HSPB1) from Platelets Is Accompanied with the Acceleration of Aggregation in Diabetic Patients.

PubMed

Tokuda, Haruhiko; Kuroyanagi, Gen; Tsujimoto, Masanori; Enomoto, Yukiko; Matsushima-Nishiwaki, Rie; Onuma, Takashi; Kojima, Akiko; Doi, Tomoaki; Tanabe, Kumiko; Akamatsu, Shigeru; Iida, Hiroki; Ogura, Shinji; Otsuka, Takanobu; Iwama, Toru; Tanikawa, Takahisa; Ishikawa, Kei; Kojima, Kumi; Kozawa, Osamu

2015-01-01

We investigated the relationship between HSP27 phosphorylation and collagen-stimulated activation of platelets in patients with diabetes mellitus (DM). Platelet-rich plasma was prepared from blood of type 2 DM patients. The platelet aggregation was analyzed in size of aggregates by an aggregometer using a laser scattering method. The protein phosphorylation was analyzed by Western blotting. Phosphorylated-HSP27 and PDGF-AB released from platelets were measured by ELISA. The phosphorylated-HSP27 levels at Ser-78 and Ser-82 induced by collagen were directly proportional to the platelet aggregation. Total HSP27 levels in platelets were decreased concomitantly with the phosphorylation. The released HSP27 levels were significantly correlated with the phosphorylated levels of HSP27 in the platelets stimulated by 0.3 μg/ml collagen. The low dose collagen-stimulated release of HSP27 was detected but relatively small in healthy donors. The released levels of PDGF-AB were in parallel with the levels of released HSP27. Area under the curve (AUC) of small aggregation (9-25 μm) induced by 0.3 μg/ml collagen was inversely proportional to the levels of released HSP27. AUC of large aggregation (50-70 μm) was directly proportional to the levels of released HSP27. Exogenous recombinant phosphorylated- HSP27 hardly affected the aggregation or the released levels of PDGF-AB induced by collagen. These results strongly suggest that HSP27 is released from human platelets accompanied with its phosphorylation induced by collagen, which is correlated with the acceleration of platelet aggregation in type 2 DM patients.

Composition of growth factors and cytokines in lysates obtained from fresh versus stored pathogen-inactivated platelet units.

PubMed

Sellberg, Felix; Berglund, Erik; Ronaghi, Martin; Strandberg, Gabriel; Löf, Helena; Sommar, Pehr; Lubenow, Norbert; Knutson, Folke; Berglund, David

2016-12-01

Platelet lysate is a readily available source of growth factors, and other mediators, which has been used in a variety of clinical applications. However, the product remains poorly standardized and the present investigation evaluates the composition of platelet lysate obtained from either fresh or stored pathogen-inactivated platelet units. Platelet pooled units (n = 10) were obtained from healthy blood donors and tested according to standard procedures. All units were pathogen inactivated using amotosalen hydrochloride and UVA exposure. Platelet lysate was subsequently produced at two separate time-points, either from fresh platelet units or after 5 days of storage, by repeated freeze-thaw cycles. The following mediators were determined at each time-point: EGF, FGF-2, VEGF, IGF-1, PDGF-AB/BB, BMP-2, PF4, TGF-β isoform 1, IL-1β, IL-2, IL-6, IL-10, IL-12p70, 1L-17A, TNF-α, and IFN-γ. The concentration of growth factors and cytokines was affected by time in storage. Notably, TGF-β, PDGF-AB/BB, and PF4 showed an increase of 27.2% (p < 0.0001), 29.5% (p = 0.04) and 8.2% (p = 0.0004), respectively. A decrease was seen in the levels of IGF-1 and FGF-2 with 22% (p = 0.041) and 11% (p = 0.01), respectively. Cytokines were present only in very low concentrations and all other growth factors remained stable with time in storage. The composition of mediators in platelet lysate obtained from pathogen-inactivated platelet units differs when produced from fresh and stored platelet units, respectively. This underscores the need for further standardization and optimization of this important product, which potentially may influence the clinical effects. Copyright © 2016. Published by Elsevier Ltd.

Effect of Photobiomodulation on Transforming Growth Factor-β1, Platelet-Derived Growth Factor-BB, and Interleukin-8 Release in Palatal Wounds After Free Gingival Graft Harvesting: A Randomized Clinical Study

PubMed Central

Lutfioğlu, Muge; Aydogdu, Ahmet; Saygun, N. Isil; Serdar, Muhittin A.

2016-01-01

Abstract Objective: This study evaluated the impact of photobiomodulation (PBM) on the healing of the donor palatal area following free gingival graft (FGG) harvesting by examining changes in transforming growth factor (TGF)-β1, platelet-derived growth factor (PDGF)-BB, and interleukin (IL)-8 levels in palatal wound fluid (PWF). Material and methods: Thirty patients were selected and randomly assigned to receive PBM (laser group) or PBM sham (sham group) in the palatine area after FGG harvesting. A neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (1064 nm) was applied to the test sites immediately after surgery and every 24 h thereafter for 4 days. PWF was collected on Days 7 and 12, and PWF TGF-β1, PDGF-BB, and IL-8 levels were analyzed by enzyme-linked immunosorbent assays (ELISA). Results: PWF TGF-β1, PDGF-BB, and IL-8 levels were significantly lower on Day 12 than on Day 7 for both groups. PWF TGF-β1, PDGF-BB, and IL-8 levels of the laser group were significantly higher than those of sham group on Day 7 (p < 0.05). PWF TGF-β1 levels were also significantly higher in laser group than in the sham group on Day 12; however, differences in PDGF-BB and IL-8 levels between groups on Day 12 were statistically nonsignificant. Conclusions: Observed increases in PWF TGF-β1, PDGF-BB, and IL-8 levels suggest that PBM may accelerate wound healing by stimulating production of selected mediators. PMID:27088277

Efficacy of leukocyte- and platelet-rich fibrin in wound healing: a randomized controlled clinical trial.

PubMed

Chignon-Sicard, Bérengère; Georgiou, Charalambos A; Fontas, Eric; David, Sylvain; Dumas, Pierre; Ihrai, Tarik; Lebreton, Elisabeth

2012-12-01

Application of platelet concentrates to wounds could speed healing. Leukocyte- and platelet-rich fibrin, a relatively recent development, stands out from the other preparations. This prospective, randomized, controlled clinical trial studied the rate of healing of postoperative hand wounds after a single application of leukocyte- and platelet-rich fibrin. Eligible patients were healthy individuals older than 18 years who had been scheduled for elective McCash (open palm) surgery for Dupuytren disease at the Plastic and Hand Surgery Department of Nice's University Hospital between August of 2007 and February of 2010. The control group received the reference care of petroleum jelly mesh (Vaselitulle), and test patients had leukocyte- and platelet-rich fibrin applied. The primary endpoint was healing delay measured in postoperative days. Secondary endpoints included pain, bleeding, and wound exudate. The trial was carried out as a single-blind trial. Among the 68 randomized patients, 33 patients in the leukocyte- and platelet-rich fibrin group and 31 in the Vaselitulle group were analyzed. Primary endpoint analysis showed a median healing delay of 24 days (interquartile range, 18 to 28 days) for the fibrin group and 29 days (interquartile range, 26 to 35 days) for the Vaselitulle group (p = 0.014, log-rank test). Postoperative pain assessment, bleeding, and exudate were always lower for the fibrin group, but not significantly so. The authors trial demonstrates that a single leukocyte- and platelet-rich fibrin application on fresh postoperative hand wounds shows a median improvement of 5 days in comparison with the standard treatment. Therapeutic, II.

Comparison of Plateletpheresis on the Fenwal Amicus and Fresenius Com.Tec Cell Separators.

PubMed

Altuntas, Fevzi; Sari, Ismail; Kocyigit, Ismail; Kaynar, Leylagul; Hacioglu, Sibel; Ozturk, Ahmet; Oztekin, Mehmet; Solmaz, Musa; Eser, Bulent; Cetin, Mustafa; Unal, Ali

2008-01-01

SUMMARY: BACKGROUND: A variety of apheresis devices are now available on the market for plateletapheresis. We compared two apheresis instruments (Fenwal Amicus and Fresenius COM.TEC) with regard to processing time, platelet (PLT) yield and efficiency, and white blood cell (WBC) content. MATERIAL AND METHODS: Donors undergoing plateletpheresis were randomly separated into two groups (either the Amicus or the COM.TEC cell separator). RESULTS: In the pre-apheresis setting, 32 plateletpheresis procedures performed with each instrument revealed no significant differences in donors' sex, age, weight, height and total blood volume between the two groups. However, the pre-apheresis PLT count was higher with the COM.TEC than with the Amicus (198 × 10(3)/μl vs. 223 × 10(3)/μl; p = 0.035). The blood volume processed to reach a target PLT yield of ≥3.3 × 10(11) was higher in the COM.TEC compared to the Amicus (3,481 vs. 2,850 ml; p < 0.001). The median separation time was also significantly longer in the COM.TEC than in the Amicus (61 vs. 44 min; p < 0.001). 91 and 88% of the PLT products collected with the Amicus and the COM.TEC, respectively, had a PLT count of >3.3 × 10(11) (p = 0.325). All products obtained with both instruments had WBC counts lower than 5 ↔ 10(6), as required. There was no statistical difference with regard to collection efficiency between the devices (55 ± 15 vs. 57 ± 15%; p = 0.477). However, the collection rate was significantly higher with the Amicus compared to the COM.TEC instrument (0.077 ± 0.012 × 10(11) vs. 0.057 ± 0.008 × 10(11) PLT/min; p < 0.001). CONCLUSION: Both instruments collected platelets efficiently. Additionally, consistent leukoreduction was obtained with both instruments; however, compared with the COM.TEC instrument, the Amicus reached the PLT target yield more quickly.

Nanomedicine for the reduction of the thrombogenicity of stent coatings

PubMed Central

Karagkiozaki, Varvara C; Logothetidis, Stergios D; Kassavetis, Spyridon N; Giannoglou, George D

2010-01-01

The treatment of patients with drug-eluting stents (DES) continues to evolve with the current emergence of DES technology that offers a combination of pharmacological and mechanical approaches to prevent arterial restenosis. However, despite the promising short-term and mid-term outcomes of DES, there are valid concerns about adverse clinical effects of late stent thrombosis. In this study, we present an example of how nanomedicine can offer solutions for improving stent coating manufacturing, by producing nanomaterials with tailored and controllable properties. The study is based on the exploitation of human platelets response towards carbon-based nanocoatings via atomic force microscope (AFM). AFM can facilitate the comprehensive analysis of platelets behavior onto stent nanocoatings and enable the study of thrombogenicity. Platelet-rich plasma from healthy donors was used for the real-time study of biointerfacial interactions. The carbon nanomaterials were developed by rf magnetron sputtering technique under controllable deposition conditions to provide favorable surface nanotopography. It was shown that by altering the surface topography of nanocoatings, the activation of platelets can be affected, while the carbon nanocoatings having higher surface roughness were found to be less thrombogenic in terms of platelets adhesion. This is an actual solution for improving the stent coating fabrication. PMID:20463940

[Allergic transfusion reactions in a patient with multiple food allergies].

PubMed

Strobel, E; Schöniger, M; Münz, M; Hiefinger-Schindlbeck, R

2012-07-01

A 13-year-old girl with an osteosarcoma was treated by surgery and chemotherapy. During three transfusions of apheresis platelet concentrates allergic reactions occurred, partly in spite of premedication with an antihistamine and a corticoid. As the patient declared to be allergic to some foods, in-vitro tests for allergen-specific IgE antibodies were performed and showed markedly positive results for specific IgE to carrot and celery, less so to hazelnut, peanut and a lot of other food antigens. The donor of one of the unsuitable platelet concentrates remembered when questioned, that he had eaten carrots and chocolate with hazelnuts during the evening before platelet donation. Two washed platelet concentrates were transfused without any problem. Furthermore, transfusions of nine red blood cell concentrates and one unit of virus-inactivated frozen pooled plasma were well tolerated. Patients should be asked for allergies previous to transfusions to be alert to allergic reactions in patients with a positive history of food or drug allergies. If premedication with antihistamines does not prevent severe allergic transfusion reactions, transfusion of washed platelet concentrates and of virus-inactivated frozen pooled plasma can be considered. © Georg Thieme Verlag KG Stuttgart · New York.

Efficacy of autologous platelet-rich plasma use for orthopaedic indications: a meta-analysis.

PubMed

Sheth, Ujash; Simunovic, Nicole; Klein, Guy; Fu, Freddie; Einhorn, Thomas A; Schemitsch, Emil; Ayeni, Olufemi R; Bhandari, Mohit

2012-02-15

The recent emergence of autologous blood concentrates, such as platelet-rich plasma, as a treatment option for patients with orthopaedic injuries has led to an extensive debate about their clinical benefit. We conducted a systematic review and meta-analysis to determine the efficacy of autologous blood concentrates in decreasing pain and improving healing and function in patients with orthopaedic bone and soft-tissue injuries. We searched MEDLINE and Embase for randomized controlled trials or prospective cohort studies that compared autologous blood concentrates with a control therapy in patients with an orthopaedic injury. We identified additional studies by searching through the bibliographies of eligible studies as well as the archives of orthopaedic conferences and meetings. Twenty-three randomized trials and ten prospective cohort studies were identified. There was a lack of consistency in outcome measures across all studies. In six randomized controlled trials (n = 358) and three prospective cohort studies (n = 88), the authors reported visual analog scale (VAS) scores when comparing platelet-rich plasma with a control therapy across injuries to the acromion, rotator cuff, lateral humeral epicondyle, anterior cruciate ligament, patella, tibia, and spine. The use of platelet-rich plasma provided no significant benefit up to (and including) twenty-four months across the randomized trials (standardized mean difference, -0.34; 95% confidence interval [CI], -0.75 to 0.06) or the prospective cohort studies (standardized mean difference, -0.20; 95% CI, -0.64 to 0.23). Both point estimates suggested a small trend favoring platelet-rich plasma, but the associated wide confidence intervals were consistent with nonsignificant effects. The current literature is complicated by a lack of standardization of study protocols, platelet-separation techniques, and outcome measures. As a result, there is uncertainty about the evidence to support the increasing clinical use of platelet-rich plasma and autologous blood concentrates as a treatment modality for orthopaedic bone and soft-tissue injuries.

Evaluation of the Spectra Optia apheresis system for mononuclear cell (MNC) collection in G-CSF mobilized and nonmobilized healthy donors: results of a multicenter study.

PubMed

Karafin, Matthew S; Graminske, Sharon; Erickson, Paulette; Walters, Mark C; Scott, Edward P; Carter, Scott; Padmanabhan, Anand

2014-10-01

The Spectra Optia apheresis system is a newer centrifugation-based device that in comparison with the COBE Spectra includes features that enhance procedure automation and usability. In this FDA-approved three-center two-arm observational study we characterized the performance of the Spectra Optia for collection of MNCs and CD34+ cells from nonmobilized and granulocyte-colony stimulating factor (G-CSF) mobilized healthy donors, respectively. There were a total of 15 evaluable subjects in each arm. Key performance indicators included collection efficiency of MNCs/CD34+ cells, product purity and cellular viability. For nonmobilized donors, median MNC collection efficiency, platelet collection efficiency, product hematocrit and granulocyte contamination were 57%, 12%, 4%, and 1.7%, respectively. For mobilized donors, median MNC collection efficiency, CD34+ cell collection efficiency, platelet collection efficiency, product hematocrit and granulocyte contamination were 61%, 77%, 19%, 4%, and 15%, respectively. Average WBC viability in the mobilized products was 99%. There was one severe (grade 3) adverse event related to citrate toxicity. This study demonstrates that the Spectra Optia can be used for safe and efficacious collection of MNCs, and results obtained are in line with expectations on collection efficiency and product characteristics. Adverse events were limited to those that are well documented in the stem-cell mobilization and leukapheresis process. As of the time of this writing, FDA 510(k) approval for use of the Spectra Optia device for MNC collection was achieved in the US based partly on the results of this study. © 2014 Wiley Periodicals, Inc.

Heterogeneous distribution of antigens on human platelets demonstrated by fluorescence flow cytometry.

PubMed

Dunstan, R A; Simpson, M B

1985-12-01

We have used fluorescence flow cytometry to analyse cell-to-cell variability in the density of platelet ABH, Ii, Lewis, P, P1A1, Bak,a and HLA class I antigens. Human IgG and IgM antibodies were used in a two-stage assay with goat FITC-conjugated antihuman IgG (H&L) antibody as the label, followed by single cell analysis of 10 000 platelets per sample using a 256-channel fluorescence flow cytometer (Becton-Dickinson FACS Analyser). Computer analysis of fluorescence intensity histograms for mean and peak channel and coefficient of variation shows that the degree of heterogeneity in platelet antigen density varies with each particular blood group. The broad fluorescence distribution curves with oligosaccharide antigens (CVs: A = 53, B = 40, I = 44, Lea = 40, P = 40) indicate that these antigens possess a greater variability in the number of sites per cell compared to the more homogeneous distribution of P1,A1 BaK,a and HLA (CVs: P1A1 = 24, HLA = 30). These findings may partly account for the mechanism by which transfusion of ABO-incompatible platelets results in a biphasic survival curve, with a period of early rapid removal of those platelets with a high density of antigen sites, followed by a relatively normal survival curve for those platelets that possess only a few or no antigen sites. In contrast, P1A1 and HLA sites are less variable in number from one platelet to another in a given donor, and immune-mediated removal would be more likely to approximate a single exponential curve.

Comparison between human and porcine thromboelastograph parameters in response to ex-vivo changes to platelets, plasma, and red blood cells.

PubMed

Sondeen, Jill L; de Guzman, Rodolfo; Amy Polykratis, Irene; Dale Prince, Malcolm; Hernandez, Orlando; Cap, Andrew P; Dubick, Michael A

2013-12-01

In the acute care setting, both the tracings and numeric outputs (R time, angle, and MA) of thrombelastography (TEG) may be used to inform treatment decisions. The objective was to determine the sensitivity of TEG to isolated changes in platelet count, hematocrit and fibrinogen concentration in human blood. As pigs have a similar coagulation system, we also compared the responses of the pig blood. Eight volunteers (>18 years of age, no anticoagulation or nonsteroidal anti-inflammatory therapy, not pregnant) were enrolled into this study. Four female anesthetized donor pigs were instrumented percutaneously with a catheter for blood collection. All blood was collected into sodium citrate. The concentration of each component (platelets, fibrinogen, and red blood cells) was changed while keeping the other components constant by use of centrifugation or preparation of each individual's plasma into platelet poor plasma, platelet rich plasma, cryoprecipitate, purified washed platelets, and packed red blood cells as appropriate. TEG (Haemoscope) analysis was performed and compared with the patients' whole blood diluted with lactated Ringer's solution. We demonstrated that the major factor affecting the MA and angle was the platelet count. In fact, reducing platelets alone resulted in TEG profiles and parameters that were similar to lactated Ringer's dilution profiles. Swine blood responses were parallel to that of human blood, although there were offsets especially of TEG-R and angle that confirmed that the swine are hypercoagulable compared with humans. Superficially similar TEG tracing patterns can be produced by divergent mechanisms associated with altered concentrations of blood components.

Comparable Outcomes after HLA-Matched Sibling and Alternative Donor Hematopoietic Cell Transplantation for Children with Fanconi Anemia and Severe Aplastic Anemia.

PubMed

Ebens, Christen L; DeFor, Todd E; Tryon, Rebecca; Wagner, John E; MacMillan, Margaret L

2018-04-01

Fanconi anemia (FA)-associated severe aplastic anemia (SAA) requires allogeneic hematopoietic cell transplantation (HCT) for cure. With the evolution of conditioning regimens over time, outcomes of alternative donor HCT (AD-HCT) have improved dramatically. We compared outcomes of HLA-matched sibling donor HCT (MSD-HCT; n = 17) and AD-HCT (n = 57) performed for FA-associated SAA at a single institution between 2001 and 2016. Overall survival at 5 years was 94% for MSD-HCT versus 86% for AD-HCT, neutrophil engraftment was 100% versus 95%, platelet recovery was 100% versus 89%, grade II-IV acute graft-versus-host disease (GVHD) was 6% versus 12%, grade III-IV acute GVHD was 6% versus 4%, and chronic GVHD was 0 versus 7%, with no statistically significant differences by type of transplant. The use of UCB was associated with decreased rates of neutrophil recovery in AD-HCT and platelet recovery in both MSD-HCT and AD-HCT. A trend toward a higher serious infection density before day +100 post-HCT was observed in AD-HCT compared with MSD-HCT (P = .02). These data demonstrate that AD-HCT should be considered at the same time as MSD-HCT for patients with FA-associated SAA. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Effects of the NO/soluble guanylate cyclase/cGMP system on the functions of human platelets.

PubMed

Makhoul, Stephanie; Walter, Elena; Pagel, Oliver; Walter, Ulrich; Sickmann, Albert; Gambaryan, Stepan; Smolenski, Albert; Zahedi, René P; Jurk, Kerstin

2018-06-01

Platelets are circulating sentinels of vascular integrity and are activated, inhibited, or modulated by multiple hormones, vasoactive substances or drugs. Endothelium- or drug-derived NO strongly inhibits platelet activation via activation of the soluble guanylate cyclase (sGC) and cGMP elevation, often in synergy with cAMP-elevation by prostacyclin. However, the molecular mechanisms and diversity of cGMP effects in platelets are poorly understood and sometimes controversial. Recently, we established the quantitative human platelet proteome, the iloprost/prostacyclin/cAMP/protein kinase A (PKA)-regulated phosphoproteome, and the interactions of the ADP- and iloprost/prostacyclin-affected phosphoproteome. We also showed that the sGC stimulator riociguat is in vitro a highly specific inhibitor, via cGMP, of various functions of human platelets. Here, we review the regulatory role of the cGMP/protein kinase G (PKG) system in human platelet function, and our current approaches to establish and analyze the phosphoproteome after selective stimulation of the sGC/cGMP pathway by NO donors and riociguat. Present data indicate an extensive and diverse NO/riociguat/cGMP phosphoproteome, which has to be compared with the cAMP phosphoproteome. In particular, sGC/cGMP-regulated phosphorylation of many membrane proteins, G-proteins and their regulators, signaling molecules, protein kinases, and proteins involved in Ca 2+ regulation, suggests that the sGC/cGMP system targets multiple signaling networks rather than a limited number of PKG substrate proteins. Copyright © 2018 Elsevier Inc. All rights reserved.

The strategies to reduce iron deficiency in blood donors randomized trial: design, enrolment and early retention

PubMed Central

Bialkowski, W.; Bryant, B. J.; Schlumpf, K. S.; Wright, D. J.; Birch, R.; Kiss, J. E.; D’Andrea, P.; Cable, R. G.; Spencer, B. R.; Vij, V.; Mast, A. E.

2014-01-01

Background and Objectives Repeated blood donation produces iron deficiency. Changes in dietary iron intake do not prevent donation-induced iron deficiency. Prolonging the interdonation interval or using oral iron supplements can mitigate donation-induced iron deficiency. The most effective operational methods for reducing iron deficiency in donors are unknown. Materials and Methods ‘Strategies To Reduce Iron Deficiency’ (STRIDE) was a two-year, randomized, placebo-controlled study in blood donors. 692 donors were randomized into one of two educational groups or one of three interventional groups. Donors randomized to educational groups either received letters thanking them for donating, or, suggesting iron supplements or delayed donation if they had low ferritin. Donors randomized to interventional groups either received placebo, 19-mg or 38-mg iron pills. Results Iron deficient erythropoiesis was present in 52.7% of males and 74.6% of females at enrolment. Adverse events within 60 days of enrolment were primarily mild gastrointestinal symptoms (64%). The incidence of de-enrolment within 60 days was more common in the interventional groups than in the educational groups (P = 0.002), but not more common in those receiving iron than placebo (P = 0.68). Conclusion The prevalence of iron deficient erythropoiesis in donors enrolled in the STRIDE study is comparable to previously described cohorts of regular blood donors. De-enrolment within 60 days was higher for donors receiving tablets, although no more common in donors receiving iron than placebo. PMID:25469720

The strategies to reduce iron deficiency in blood donors randomized trial: design, enrolment and early retention.

PubMed

Bialkowski, W; Bryant, B J; Schlumpf, K S; Wright, D J; Birch, R; Kiss, J E; D'Andrea, P; Cable, R G; Spencer, B R; Vij, V; Mast, A E

2015-02-01

Repeated blood donation produces iron deficiency. Changes in dietary iron intake do not prevent donation-induced iron deficiency. Prolonging the interdonation interval or using oral iron supplements can mitigate donation-induced iron deficiency. The most effective operational methods for reducing iron deficiency in donors are unknown. 'Strategies To Reduce Iron Deficiency' (STRIDE) was a two-year, randomized, placebo-controlled study in blood donors. 692 donors were randomized into one of two educational groups or one of three interventional groups. Donors randomized to educational groups either received letters thanking them for donating, or, suggesting iron supplements or delayed donation if they had low ferritin. Donors randomized to interventional groups either received placebo, 19-mg or 38-mg iron pills. Iron deficient erythropoiesis was present in 52·7% of males and 74·6% of females at enrolment. Adverse events within 60 days of enrolment were primarily mild gastrointestinal symptoms (64%). The incidence of de-enrolment within 60 days was more common in the interventional groups than in the educational groups (P = 0·002), but not more common in those receiving iron than placebo (P = 0·68). The prevalence of iron deficient erythropoiesis in donors enrolled in the STRIDE study is comparable to previously described cohorts of regular blood donors. De-enrolment within 60 days was higher for donors receiving tablets, although no more common in donors receiving iron than placebo. © 2014 International Society of Blood Transfusion.

A prospective randomized clinical trial of vincristine versus human intravenous immunoglobulin for acute adjunctive management of presumptive primary immune-mediated thrombocytopenia in dogs.

PubMed

Balog, K; Huang, A A; Sum, S O; Moore, G E; Thompson, C; Scott-Moncrieff, J C

2013-01-01

Dogs with immune-mediated thrombocytopenia (ITP) are at risk of hemorrhage when platelet count is <50,000/μL. Treatment with vincristine (VINC) or human intravenous immunoglobulin (hIVIG) decreases platelet recovery time compared with treatment with corticosteroids alone. To compare the effect of hIVIG versus VINC on platelet recovery in dogs with ITP. Prospective, randomized study. Twenty dogs with idiopathic ITP (platelet count <16,000/μL) were enrolled. All dogs were treated with corticosteroids. Dogs were randomly assigned to receive a single dose of hIVIG (0.5 g/kg) or VINC (0.02 mg/kg). Outcome measures were platelet recovery time, duration of hospitalization, and survival to discharge. There was no significant difference in age, sex, weight, or initial platelet count between dogs treated with hIVIG (n = 10) and dogs treated with VINC (n = 10). Median platelet recovery time for both groups was 2.5 days (P = .51). Median hospitalization time for all dogs that survived to discharge was 4 days and not different between groups (P = .29). Seven of 10 dogs in the hIVIG group and 10 of 10 in the VINC group survived to discharge. Survival analysis did not identify any significant difference between the groups at discharge, 6 months, and 1 year after entry into the study. No adverse effects were reported in either group. Vincristine should be the first-line adjunctive treatment for the acute management of canine ITP because of lower cost and ease of administration compared with human intravenous immunoglobulin (hIVIG). Copyright © 2013 by the American College of Veterinary Internal Medicine.

Concise review: stem cell-based approaches to red blood cell production for transfusion.

PubMed

Shah, Siddharth; Huang, Xiaosong; Cheng, Linzhao

2014-03-01

Blood transfusion is a common procedure in modern medicine, and it is practiced throughout the world; however, many countries report a less than sufficient blood supply. Even in developed countries where the supply is currently adequate, projected demographics predict an insufficient supply as early as 2050. The blood supply is also strained during occasional widespread disasters and crises. Transfusion of blood components such as red blood cells (RBCs), platelets, or neutrophils is increasingly used from the same blood unit for multiple purposes and to reduce alloimmune responses. Even for RBCs and platelets lacking nuclei and many antigenic cell-surface molecules, alloimmunity could occur, especially in patients with chronic transfusion requirements. Once alloimmunization occurs, such patients require RBCs from donors with a different blood group antigen combination, making it a challenge to find donors after every successive episode of alloimmunization. Alternative blood substitutes such as synthetic oxygen carriers have so far proven unsuccessful. In this review, we focus on current research and technologies that permit RBC production ex vivo from hematopoietic stem cells, pluripotent stem cells, and immortalized erythroid precursors.

Differential Interaction of Platelet-Derived Extracellular Vesicles with Leukocyte Subsets in Human Whole Blood.

PubMed

Weiss, René; Gröger, Marion; Rauscher, Sabine; Fendl, Birgit; Eichhorn, Tanja; Fischer, Michael B; Spittler, Andreas; Weber, Viktoria

2018-04-26

Secretion and exchange of biomolecules via extracellular vesicles (EVs) are crucial mechanisms in intercellular communication, and the roles of EVs in infection, inflammation, or thrombosis have been increasingly recognized. EVs have emerged as central players in immune regulation and can enhance or suppress the immune response, depending on the state of donor and recipient cells. We investigated the interaction of blood cell-derived EVs with leukocyte subpopulations (monocytes and their subsets, granulocytes, B cells, T cells, and NK cells) directly in whole blood using a combination of flow cytometry, imaging flow cytometry, cell sorting, and high resolution confocal microscopy. Platelet-derived EVs constituted the majority of circulating EVs and were preferentially associated with granulocytes and monocytes, while they scarcely interacted with lymphocytes. Further flow cytometric differentiation of monocyte subsets provided clear indications for a preferential association of platelet-derived EVs with intermediate (CD14 ++ CD16 + ) monocytes in whole blood.

Overcoming the bottleneck of platelet lysate supply in large-scale clinical expansion of adipose-derived stem cells: A comparison of fresh versus three types of platelet lysates from outdated buffy coat-derived platelet concentrates.

PubMed

Glovinski, Peter V; Herly, Mikkel; Mathiasen, Anders B; Svalgaard, Jesper D; Borup, Rehannah; Talman, Maj-Lis M; Elberg, Jens J; Kølle, Stig-Frederik T; Drzewiecki, Krzysztof T; Fischer-Nielsen, Anne

2017-02-01

Platelet lysates (PL) represent a promising replacement for xenogenic growth supplement for adipose-derived stem cell (ASC) expansions. However, fresh platelets from human blood donors are not clinically feasible for large-scale cell expansion based on their limited supply. Therefore, we tested PLs prepared via three methods from outdated buffy coat-derived platelet concentrates (PCs) to establish an efficient and feasible expansion of ASCs for clinical use. PLs were prepared by the freeze-thaw method from freshly drawn platelets or from outdated buffy coat-derived PCs stored in the platelet additive solution, InterSol. Three types of PLs were prepared from outdated PCs with platelets suspended in either (1) InterSol (not manipulated), (2) InterSol + supplemented with plasma or (3) plasma alone (InterSol removed). Using these PLs, we compared ASC population doubling time, cell yield, differentiation potential and cell surface markers. Gene expression profiles were analyzed using microarray assays, and growth factor concentrations in the cell culture medium were measured using enzyme-linked immunosorbent assay (ELISA). Of the three PL compositions produced from outdated PCs, removal of Intersol and resuspension in plasma prior to the first freezing process was overall the best. This specific outdated PL induced ASC growth kinetics, surface markers, plastic adherence and differentiation potentials comparable with PL from fresh platelets. ASCs expanded in PL from fresh versus outdated PCs exhibited different expressions of 17 overlapping genes, of which 10 were involved in cellular proliferation, although not significantly reflected by cell growth. Only minor differences in growth factor turnover were observed. PLs from outdated platelets may be an efficient and reliable source of human growth supplement allowing for large-scale ASC expansion for clinical use. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Improved circulating microparticle analysis in acid-citrate dextrose (ACD) anticoagulant tube.

PubMed

György, Bence; Pálóczi, Krisztina; Kovács, Alexandra; Barabás, Eszter; Bekő, Gabriella; Várnai, Katalin; Pállinger, Éva; Szabó-Taylor, Katalin; Szabó, Tamás G; Kiss, Attila A; Falus, András; Buzás, Edit I

2014-02-01

Recently extracellular vesicles (exosomes, microparticles also referred to as microvesicles and apoptotic bodies) have attracted substantial interest as potential biomarkers and therapeutic vehicles. However, analysis of microparticles in biological fluids is confounded by many factors such as the activation of cells in the blood collection tube that leads to in vitro vesiculation. In this study we aimed at identifying an anticoagulant that prevents in vitro vesiculation in blood plasma samples. We compared the levels of platelet microparticles and non-platelet-derived microparticles in platelet-free plasma samples of healthy donors. Platelet-free plasma samples were isolated using different anticoagulant tubes, and were analyzed by flow cytometry and Zymuphen assay. The extent of in vitro vesiculation was compared in citrate and acid-citrate-dextrose (ACD) tubes. Agitation and storage of blood samples at 37 °C for 1 hour induced a strong release of both platelet microparticles and non-platelet-derived microparticles. Strikingly, in vitro vesiculation related to blood sample handling and storage was prevented in samples in ACD tubes. Importantly, microparticle levels elevated in vivo remained detectable in ACD tubes. We propose the general use of the ACD tube instead of other conventional anticoagulant tubes for the assessment of plasma microparticles since it gives a more realistic picture of the in vivo levels of circulating microparticles and does not interfere with downstream protein or RNA analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Platelet-, leucocyte- and red cell-derived microparticles in stored whole blood, with and without leucofiltration, with and without ionising radiation

PubMed Central

Saito, Shunnichi; Ngoma, Alain M.; Ono, Takako; Ohto, Hitoshi

2018-01-01

Background Storage lesion, including microparticle formation, has been partially characterised in whole blood, but not in all combinations of pre-storage leucofiltration and/or irradiation. Materials and methods Single-donor whole blood products were processed into four subunits: with and without leucofiltration, with and without X-irradiation (25 Gy). Platelet-, leucocyte-, and erythrocyte-derived microparticles and free haemoglobin were measured periodically throughout 42 days of storage. Results Pre-storage leucofiltration substantially reduced platelet- and leucocyte-derived microparticle counts throughout storage. Irradiation, in contrast, had no significant effect on microparticle counts. A gate for all microparticles showed a substantial time-dependent increase in unfiltered whole blood. A time-dependent increase in free haemoglobin was greatest in unfiltered, irradiated whole blood. Discussion This study indicates that leucofiltration can prevent the formation of leucocyte- and platelet-derived microparticles, and might reduce haemolysis in irradiated whole blood, either by removing factors that provoke haemolysis, or by selective retention of senescent or effete red cells most prone to haemolysis. PMID:27893349

Optimized human platelet lysate as novel basis for a serum-, xeno-, and additive-free corneal endothelial cell and tissue culture.

PubMed

Thieme, Daniel; Reuland, Lynn; Lindl, Toni; Kruse, Friedrich; Fuchsluger, Thomas

2018-02-01

The expansion of donor-derived corneal endothelial cells (ECs) is a promising approach for regenerative therapies in corneal diseases. To achieve the best Good Manufacturing Practice standard the entire cultivation process should be devoid of nonhuman components. However, so far, there is no suitable xeno-free protocol for clinical applications. We therefore introduce a processed variant of a platelet lysate for the use in corneal cell and tissue culture based on a Good Manufacturing Practice-grade thrombocyte concentrate. This processed human platelet lysate (phPL), free of any animal components and of anticoagulants such as heparin with a physiological ionic composition, was used to cultivate corneal ECs in vitro and ex vivo in comparison to standard cultivation with fetal calf serum (FCS). Human donor corneas were cut in quarters while 2 quarters of each cornea were incubated with the respective medium supplement. Three fields of view per quarter were taken into account for the analysis. Evaluation of phPL as a medium supplement in cell culture of immortalized EC showed a superior viability compared with FCS control with reduced cell proliferation. Furthermore, the viability during the expansion of primary cells is significantly (3-fold ±0.5) increased with phPL compared with FCS standard medium. Quartering donor corneas was traumatic for the endothelium and therefore resulted in increased EC loss. Interestingly, however, cultivation of the quartered pieces for 2 weeks in 0.1-mg/ml pHPL in Biochrome I showed a 21 (±10) % EC loss compared with 67 (±12) % EC loss when cultivated in 2% FCS in Biochrome I. The cell culture protocol with pHPL as FCS replacement seems to be superior to the standard FCS protocols with respect to EC survival. It offers a xeno-free and physiological environment for corneal endothelial cells. This alternative cultivation protocol could facilitate the use of EC for human corneal cell therapy. Copyright © 2017 John Wiley & Sons, Ltd.

Mineralization by mesenchymal stromal cells is variously modulated depending on commercial platelet lysate preparations.

PubMed

Boraldi, Federica; Burns, Jorge S; Bartolomeo, Angelica; Dominici, Massimo; Quaglino, Daniela

2018-03-01

Numerous cellular models have been developed to investigate calcification for regenerative medicine applications and for the identification of therapeutic targets in various complications associated with age-related diseases. However, results have often been contradictory due to specific culture conditions, cell type ontogeny and aging status. Human platelet lysate (hPL) has been recently investigated as valuable alternative to fetal bovine serum (FBS) in cell culture and bone regeneration. A parallel comparison of how all these multiple factors may converge to influence mineralization has yet to be reported. To compare mineralization of human mesenchymal cell types known to differ in extracellular matrix calcification potency, bone marrow-derived mesenchymal stromal cells and dermal fibroblasts from neonatal and adult donors, at both low and high passages, were investigated in an ex vivo experimental model by supplementing the osteogenic induction medium with FBS or with hPL. Four commercial hPL preparations were profiled by liquid chromatography/electrospray ionization quadrupole time-of-flight spectrometry, and mineralization was visualized by von Kossa staining and quantified by morphometric evaluations after 9, 14 and 21 days of culture. Data demonstrate that (i) commercial hPL preparations differ according to mass spectra profiles, (ii) hPL variously influences mineral deposition depending on cell line and possibly on platelet product preparation methods, (iii) donor age modifies mineral deposition in the presence of the same hPL and (iv) reduced in vitro proliferative capacity affects osteogenic induction and response to hPL. Despite the standardized procedures applied to obtain commercial hPL, this study highlights the divergent effects of different preparations and emphasizes the importance of cellular ontology, donor age and cell proliferative capacity to optimize the osteogenic induction capabilities of mesenchymal stromal cells and design more effective cell-based therapeutic protocols. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Platelet-rich plasma can replace fetal bovine serum in human meniscus cell cultures.

PubMed

Gonzales, Veronica K; de Mulder, Eric L W; de Boer, Trix; Hannink, Gerjon; van Tienen, Tony G; van Heerde, Waander L; Buma, Pieter

2013-11-01

Concerns over fetal bovine serum (FBS) limit the clinical application of cultured tissue-engineered constructs. Therefore, we investigated if platelet-rich plasma (PRP) can fully replace FBS for meniscus tissue engineering purposes. Human PRP and platelet-poor plasma (PPP) were isolated from three healthy adult donors. Human meniscal fibrochondrocytes (MFCs) were isolated from resected tissue after a partial meniscectomy on a young patient. Passage-4 MFCs were cultured in monolayer for 24 h, and 3 and 7 days. Six different culture media were used containing different amounts of either PRP or PPP and compared to a medium containing 10% FBS. dsDNA was quantified, and gene expression levels of collagen types I and II and aggrecan were measured at different time points with quantitative polymerase chain reaction in the cultured MFCs. After 7 days, the dsDNA quantity was significantly higher in MFCs cultured in 10% and 20% PRP compared to the other PRP and PPP conditions, but equal to 10% FBS. Collagen type I expression was lower in MFCs cultured with medium containing 5% PRP, 10% and 20% PPP compared to FBS. When medium with 10% PRP or 20% PRP was used, expressions were not significantly different from medium containing 10% FBS. Collagen type II expression was absent in all medium conditions. Aggrecan expression did not show differences between the different media used. However, after 7 days a higher aggrecan expression was measured in most culture conditions, except for 5% PRP, which was similar compared to FBS. Statistical significance was found between donors at various time points in DNA quantification and gene expression, but the same donors were not statistically different in all conditions. At 7 days cell cultured with 10% PRP and 20% PRP showed a higher density, with large areas of clusters, compared to other conditions. In an MFC culture medium, FBS can be replaced by 10% PRP or 20% PRP without altering proliferation and gene expression of human MFCs.

Autoregulation of von Willebrand factor function by a disulfide bond switch

PubMed Central

Butera, Diego; Passam, Freda; Ju, Lining; Cook, Kristina M.; Woon, Heng; Aponte-Santamaría, Camilo; Gardiner, Elizabeth; Davis, Amanda K.; Murphy, Deirdre A.; Bronowska, Agnieszka; Luken, Brenda M.; Baldauf, Carsten; Jackson, Shaun; Andrews, Robert; Gräter, Frauke; Hogg, Philip J.

2018-01-01

Force-dependent binding of platelet glycoprotein Ib (GPIb) receptors to plasma von Willebrand factor (VWF) plays a key role in hemostasis and thrombosis. Previous studies have suggested that VWF activation requires force-induced exposure of the GPIb binding site in the A1 domain that is autoinhibited by the neighboring A2 domain. However, the biochemical basis of this “mechanopresentation” remains elusive. From a combination of protein chemical, biophysical, and functional studies, we find that the autoinhibition is controlled by the redox state of an unusual disulfide bond near the carboxyl terminus of the A2 domain that links adjacent cysteine residues to form an eight-membered ring. Only when the bond is cleaved does the A2 domain bind to the A1 domain and block platelet GPIb binding. Molecular dynamics simulations indicate that cleavage of the disulfide bond modifies the structure and molecular stresses of the A2 domain in a long-range allosteric manner, which provides a structural explanation for redox control of the autoinhibition. Significantly, the A2 disulfide bond is cleaved in ~75% of VWF subunits in healthy human donor plasma but in just ~25% of plasma VWF subunits from heart failure patients who have received extracorporeal membrane oxygenation support. This suggests that the majority of plasma VWF binding sites for platelet GPIb are autoinhibited in healthy donors but are mostly available in heart failure patients. These findings demonstrate that a disulfide bond switch regulates mechanopresentation of VWF. PMID:29507883

Autoregulation of von Willebrand factor function by a disulfide bond switch.

PubMed

Butera, Diego; Passam, Freda; Ju, Lining; Cook, Kristina M; Woon, Heng; Aponte-Santamaría, Camilo; Gardiner, Elizabeth; Davis, Amanda K; Murphy, Deirdre A; Bronowska, Agnieszka; Luken, Brenda M; Baldauf, Carsten; Jackson, Shaun; Andrews, Robert; Gräter, Frauke; Hogg, Philip J

2018-02-01

Force-dependent binding of platelet glycoprotein Ib (GPIb) receptors to plasma von Willebrand factor (VWF) plays a key role in hemostasis and thrombosis. Previous studies have suggested that VWF activation requires force-induced exposure of the GPIb binding site in the A1 domain that is autoinhibited by the neighboring A2 domain. However, the biochemical basis of this "mechanopresentation" remains elusive. From a combination of protein chemical, biophysical, and functional studies, we find that the autoinhibition is controlled by the redox state of an unusual disulfide bond near the carboxyl terminus of the A2 domain that links adjacent cysteine residues to form an eight-membered ring. Only when the bond is cleaved does the A2 domain bind to the A1 domain and block platelet GPIb binding. Molecular dynamics simulations indicate that cleavage of the disulfide bond modifies the structure and molecular stresses of the A2 domain in a long-range allosteric manner, which provides a structural explanation for redox control of the autoinhibition. Significantly, the A2 disulfide bond is cleaved in ~75% of VWF subunits in healthy human donor plasma but in just ~25% of plasma VWF subunits from heart failure patients who have received extracorporeal membrane oxygenation support. This suggests that the majority of plasma VWF binding sites for platelet GPIb are autoinhibited in healthy donors but are mostly available in heart failure patients. These findings demonstrate that a disulfide bond switch regulates mechanopresentation of VWF.

Impact of blood products on platelet function in patients with traumatic injuries: a translational study.

PubMed

Henriksen, Hanne Hee; Grand, Alexandra G; Viggers, Sandra; Baer, Lisa A; Solbeck, Sacha; Cotton, Bryan A; Matijevic, Nena; Ostrowski, Sisse R; Stensballe, Jakob; Fox, Erin E; Chen, Tzu-An; Holcomb, John B; Johansson, Pär I; Cardenas, Jessica C; Wade, Charles E

2017-06-15

Reductions in platelet (PLT) count and function are associated with poor outcomes in trauma patients. We proposed to determine if patients expected to receive blood products have a decrease in PLT function higher than expected based on the reduction in PLT count, and if the reduction in function could be associated with the donor plasma/supernatant received. PLT count and function were measured on admission to the emergency department and intensive care unit in severely injured patients expected to receive a transfusion. PLT function was measured by Multiplate aggregometry in response to five agonists. Function was corrected for alterations in count. In vitro studies were conducted in the blood of normal subjects to assess the effect of dilutions with AB donor plasma on PLT function. Forty-six patients were enrolled, with 87% requiring a transfusion. Median Injury Severity Score was 23 (13, 29) and mortality 15%. PLT count and function were decreased from emergency department to intensive care unit admission by 25% and 58%, respectively. Decreases in function persisted after adjustment for count. Patients requiring large volumes of blood products had reductions in function that were disproportionately greater. Reductions in PLT function were greatest after transfusion of PLTs. In in vitro studies with a 30% dilution by autologous plasma caused a relational reduction in function, whereas allogenic plasma resulted in greater decreases that were highly variable between donors. Within hours of injury a decrease in both PLT count and function occurs, that is aggravated with the administration of blood products, with transfusion of PLTs showing the greatest effect. The effect on PLT function of allogenic transfused plasma appears to be highly donor related. Copyright © 2017 Elsevier Inc. All rights reserved.

PARot--assessing platelet-rich plasma plus arthroscopic subacromial decompression in the treatment of rotator cuff tendinopathy: study protocol for a randomized controlled trial.

PubMed

Carr, Andrew; Cooper, Cushla; Murphy, Richard; Watkins, Bridget; Wheway, Kim; Rombach, Ines; Beard, David

2013-06-11

Platelet-rich plasma (PRP) is an autologous platelet concentrate. It is prepared by separating the platelet fraction of whole blood from patients and mixing it with an agent to activate the platelets. In a clinical setting, PRP may be reapplied to the patient to improve and hasten the healing of tissue. The therapeutic effect is based on the presence of growth factors stored in the platelets. Current evidence in orthopedics shows that PRP applications can be used to accelerate bone and soft tissue regeneration following tendon injuries and arthroplasty. Outcomes include decreased inflammation, reduced blood loss and post-treatment pain relief. Recent shoulder research indicates there is poor vascularization present in the area around tendinopathies and this possibly prevents full healing capacity post surgery (Am J Sports Med36(6):1171-1178, 2008). Although it is becoming popular in other areas of orthopedics there is little evidence regarding the use of PRP for shoulder pathologies. The application of PRP may help to revascularize the area and consequently promote tendon healing. Such evidence highlights an opportunity to explore the efficacy of PRP use during arthroscopic shoulder surgery for rotator cuff pathologies. PARot is a single center, blinded superiority-type randomized controlled trial assessing the clinical outcomes of PRP applications in patients who undergo shoulder surgery for rotator cuff disease. Patients will be randomized to one of the following treatment groups: arthroscopic subacromial decompression surgery or arthroscopic subacromial decompression surgery with application of PRP. Current Controlled Trials: ISRCTN10464365.

Aspirin therapy reduces the ability of platelets to promote colon and pancreatic cancer cell proliferation: Implications for the oncoprotein c-MYC

PubMed Central

Sylman, Joanna L.; Ngo, Anh T. P.; Pang, Jiaqing; Sears, Rosalie C.; Williams, Craig D.; McCarty, Owen J. T.

2017-01-01

Aspirin, an anti-inflammatory and antithrombotic drug, has become the focus of intense research as a potential anticancer agent owing to its ability to reduce tumor proliferation in vitro and to prevent tumorigenesis in patients. Studies have found an anticancer effect of aspirin when used in low, antiplatelet doses. However, the mechanisms through which low-dose aspirin works are poorly understood. In this study, we aimed to determine the effect of aspirin on the cross talk between platelets and cancer cells. For our study, we used two colon cancer cell lines isolated from the same donor but characterized by different metastatic potential, SW480 (nonmetastatic) and SW620 (metastatic) cancer cells, and a pancreatic cancer cell line, PANC-1 (nonmetastatic). We found that SW480 and PANC-1 cancer cell proliferation was potentiated by human platelets in a manner dependent on the upregulation and activation of the oncoprotein c-MYC. The ability of platelets to upregulate c-MYC and cancer cell proliferation was reversed by an antiplatelet concentration of aspirin. In conclusion, we show for the first time that inhibition of platelets by aspirin can affect their ability to induce cancer cell proliferation through the modulation of the c-MYC oncoprotein. PMID:27903583

LC-MS Analysis of Human Platelets as a Platform for Studying Mitochondrial Metabolism

PubMed Central

Parry, Robert C.; Wang, Qingqing; Gillespie, Kevin P.; Saillant, Noelle N.; Sims, Carrie; Mesaros, Clementina; Snyder, Nathaniel W.; Blair, Ian A.

2016-01-01

Perturbed mitochondrial metabolism has received renewed interest as playing a causative role in a range of diseases. Probing alterations to metabolic pathways requires a model in which external factors can be well controlled, allowing for reproducible and meaningful results. Many studies employ transformed cellular models for these purposes; however, metabolic reprogramming that occurs in many cancer cell lines may introduce confounding variables. For this reason primary cells are desirable, though attaining adequate biomass for metabolic studies can be challenging. Here we show that human platelets can be utilized as a platform to carry out metabolic studies in combination with liquid chromatography-tandem mass spectrometry analysis. This approach is amenable to relative quantification and isotopic labeling to probe the activity of specific metabolic pathways. Availability of platelets from individual donors or from blood banks makes this model system applicable to clinical studies and feasible to scale up. Here we utilize isolated platelets to confirm previously identified compensatory metabolic shifts in response to the complex I inhibitor rotenone. More specifically, a decrease in glycolysis is accompanied by an increase in fatty acid oxidation to maintain acetyl-CoA levels. Our results show that platelets can be used as an easily accessible and medically relevant model to probe the effects of xenobiotics on cellular metabolism. PMID:27077278

Platelet-rich plasma for long bone healing

PubMed Central

Lenza, Mário; Ferraz, Silvia de Barros; Viola, Dan Carai Maia; dos Santos, Oscar Fernando Pavão; Cendoroglo, Miguel; Ferretti, Mario

2013-01-01

ABSTRACT Objective: To evaluate effectiveness of the use of platelet-rich plasma as coadjuvant for union of long bones. Methods: The search strategy included the Cochrane Library (via Central) and MEDLINE (via PubMed). There were no limits as to language or publication media. The latest search strategy was conducted in December 2011. It included randomized clinical trials that evaluated the use of platelet-rich plasma as coadjuvant medication to accelerate union of long bones (acute fractures, pseudoarthrosis and bone defects). The outcomes of interest for this review include bone regeneration, adverse events, costs, pain, and quality of life. The authors selected eligible studies, evaluated the methodological quality, and extracted the data. It was not possible to perform quantitative analysis of the grouped studies (meta-analyses). Results: Two randomized prospective clinical trials were included, with a total of 148 participants. One of them compared recombinant human morphogenic bone protein-7 versus platelet-rich plasma for the treatment of pseudoarthrosis; the other evaluated the effects of three coadjuvant treatments for union of valgising tibial osteotomies (platelet-rich plasma, platelet-rich plasma plus bone marrow stromal cells, and no coadjuvant treatment). Both had low statistical power and moderate to high risk of bias. Conclusion: There was no conclusive evidence that sustained the use of platelet-rich plasma as a coadjuvant to aid bone regeneration of fractures, pseudoarthrosis, or bone defects. PMID:23579757

A double-blind, randomized, multicenter phase 2 study of prasugrel versus placebo in adult patients with sickle cell disease

PubMed Central

2013-01-01

Background Platelet activation has been implicated in the pathogenesis of sickle cell disease (SCD) suggesting antiplatelet agents may be therapeutic. To evaluate the safety of prasugrel, a thienopyridine antiplatelet agent, in adult patients with SCD, we conducted a double-blind, randomized, placebo-controlled study. Methods The primary endpoint, safety, was measured by hemorrhagic events requiring medical intervention. Patients were randomized to prasugrel 5 mg daily (n = 41) or placebo (n = 21) for 30 days. Platelet function by VerifyNow® P2Y12 and vasodilator-stimulated phosphoprotein assays at days 10 and 30 were significantly inhibited in prasugrel- compared with placebo-treated SCD patients. Results There were no hemorrhagic events requiring medical intervention in either study arm. Mean pain rate (percentage of days with pain) and intensity in the prasugrel arm were decreased compared with placebo. However, these decreases did not reach statistical significance. Platelet surface P-selectin and plasma soluble P-selectin, biomarkers of in vivo platelet activation, were significantly reduced in SCD patients receiving prasugrel compared with placebo. In sum, prasugrel was well tolerated and not associated with serious hemorrhagic events. Conclusions Despite the small size and short duration of this study, there was a decrease in platelet activation biomarkers and a trend toward decreased pain. PMID:23414938

Multiwavelength UV/visible spectroscopy for the quantitative investigation of platelet quality

NASA Astrophysics Data System (ADS)

Mattley, Yvette D.; Leparc, German F.; Potter, Robert L.; Garcia-Rubio, Luis H.

1998-04-01

The quality of platelets transfused is vital to the effectiveness of the transfusion. Freshly prepared, discoid platelets are the most effective treatment for preventing spontaneous hemorrhage or for stopping an abnormal bleeding event. Current methodology for the routine testing of platelet quality involves random pH testing of platelet rich plasma and visual inspection of platelet rich plasma for a swirling pattern indicative of the discoid shape of the cells. The drawback to these methods is that they do not provide a quantitative and objective assay for platelet functionality that can be used on each platelet unit prior to transfusion. As part of a larger project aimed at characterizing whole blood and blood components with multiwavelength UV/vis spectroscopy, isolated platelets and platelet in platelet rich plasma have been investigated. Models based on Mie theory have been developed which allow for the extraction of quantitative information on platelet size, number and quality from multi-wavelength UV/vis spectra. These models have been used to quantify changes in platelet rich plasma during storage. The overall goal of this work is to develop a simple, rapid quantitative assay for platelet quality that can be used prior to platelet transfusion to ensure the effectiveness of the treatment. As a result of this work, the optical properties for isolated platelets, platelet rich plasma and leukodepleted platelet rich plasma have been determined.

Implementation of buffy-coat-derived pooled platelet concentrates for internal quality control of light transmission aggregometry: a proof of concept study.

PubMed

Prüller, F; Rosskopf, K; Mangge, H; Mahla, E; von Lewinski, D; Weiss, E C; Riegler, A; Enko, D

2017-12-01

Essentials In platelet function testing, standardized internal controls (IQC) are not commercially provided. Platelet function testing was performed daily on aliquoted pooled platelet concentrates. Pooled platelet concentrates showed stability for control purposes from Monday to Friday. Pooled platelet concentrates provide the necessary steadiness to serve as IQC material. Background Standardized commercially available control material for internal quality control (IQC) of light transmission aggregometry (LTA) is still lacking. Moreover, the availability of normal blood donors to provide fresh platelets is difficult in small laboratories, where 'volunteers' may be in short supply. Objectives To evaluate the implementation of buffy-coat-derived pooled platelet concentrates (PCs) for IQC material for LTA. Methods We used buffy-coat-derived pooled PCs from the blood bank as IQC material for LTA. On each weekend one PC was prepared (> 200 mL) and aliquoted from the original storage bag on a daily basis in four baby bags (40-50 mL), which were delivered from Monday to Friday to our laboratory. The IQC measurements of at least 85 work-weeks (from Monday to Friday) were evaluated with this new IQC material. LTA was performed on a four-channel Chronolog 700 Aggregometer (Chronolog Corporation, Havertown, PA, USA) (agonists: collagen, adenosine diphosphate [ADP], arachidonic acid [AA] and thrombin receptor activator peptide-6 [TRAP-6]). Results The medians of platelet aggregation from IQC measurements with collagen, ADP and AA from Monday to Friday were 68.0-59.5, 3.0-2.0 and 51.0-50.0%, respectively, and the mean of platelet aggregation with TRAP-6 was 71.2-66.4%. Conclusions Buffy-coat-derived pooled PCs serve as a reliable and robust IQC material for LTA measurements and would be beneficial for the whole laboratory procedure and employees' safety. © 2017 International Society on Thrombosis and Haemostasis.

Platelet lysate as a substitute for animal serum for the ex-vivo expansion of mesenchymal stem/stromal cells: present and future.

PubMed

Astori, Giuseppe; Amati, Eliana; Bambi, Franco; Bernardi, Martina; Chieregato, Katia; Schäfer, Richard; Sella, Sabrina; Rodeghiero, Francesco

2016-07-13

The use of fetal bovine serum (FBS) as a cell culture supplement is discouraged by regulatory authorities to limit the risk of zoonoses and xenogeneic immune reactions in the transplanted host. Additionally, FBS production came under scrutiny due to animal welfare concerns. Platelet derivatives have been proposed as FBS substitutes for the ex-vivo expansion of mesenchymal stem/stromal cells (MSCs) since platelet-derived growth factors can promote MSC ex-vivo expansion. Platelet-derived growth factors are present in platelet lysate (PL) obtained after repeated freezing-thawing cycles of the platelet-rich plasma or by applying physiological stimuli such as thrombin or CaCl2.PL-expanded MSCs have been used already in the clinic, taking advantage of their faster proliferation compared with FBS-expanded preparations. Should PL be applied to other biopharmaceutical products, its demand is likely to increase dramatically. The use of fresh platelet units for the production of PL raises concerns due to limited availability of platelet donors. Expired units might represent an alternative, but further data are needed to define safety, including pathogen reduction, and functionality of the obtained PL. In addition, relevant questions concerning the definition of PL release criteria, including concentration ranges of specific growth factors in PL batches for various clinical indications, also need to be addressed. We are still far from a common definition of PL and standardized PL manufacture due to our limited knowledge of the mechanisms that mediate PL-promoting cell growth. Here, we concisely discuss aspects of PL as MSC culture supplement as a preliminary step towards an agreed definition of the required characteristics of PL for the requirements of manufacturers and users.

Platelet sequestration and activation during GalTKO.hCD46 pig lung perfusion by human blood is primarily mediated by GPIb, GPIIb/IIIa, and von Willebrand Factor.

PubMed

Burdorf, L; Riner, A; Rybak, E; Salles, I I; De Meyer, S F; Shah, A; Quinn, K J; Harris, D; Zhang, T; Parsell, D; Ali, F; Schwartz, E; Kang, E; Cheng, X; Sievert, E; Zhao, Y; Braileanu, G; Phelps, C J; Ayares, D L; Deckmyn, H; Pierson, R N; Azimzadeh, A M; Dandro, Amy; Karavi, Kasinath

2016-05-01

Here, we ask whether platelet GPIb and GPIIb/IIIa receptors modulate platelet sequestration and activation during GalTKO.hCD46 pig lung xenograft perfusion. GalTKO.hCD46 transgenic pig lungs were perfused with heparinized fresh human blood. Results from perfusions in which αGPIb Fab (6B4, 10 mg/l blood, n = 6), αGPIIb/IIIa Fab (ReoPro, 3.5 mg/l blood, n = 6), or both drugs (n = 4) were administered to the perfusate were compared to two additional groups in which the donor pig received 1-desamino-8-d-arginine vasopressin (DDAVP), 3 μg/kg (to pre-deplete von Willebrand Factor (pVWF), the main GPIb ligand), with or without αGPIb (n = 6 each). Platelet sequestration was significantly delayed in αGPIb, αGPIb+DDAVP, and αGPIb+αGPIIb/IIIa groups. Median lung "survival" was significantly longer (>240 vs. 162 min reference, p = 0.016), and platelet activation (as CD62P and βTG) were significantly inhibited, when pigs were pre-treated with DDAVP, with or without αGPIb Fab treatment. Pulmonary vascular resistance rise was not significantly attenuated in any group, and was associated with residual thromboxane and histamine elaboration. The GPIb-VWF and GPIIb/IIIa axes play important roles in platelet sequestration and coagulation cascade activation during GalTKO.hCD46 lung xenograft injury. GPIb blockade significantly reduces platelet activation and delays platelet sequestration in this xenolung rejection model, an effect amplified by adding αGPIIb/IIIa blockade or depletion of VWF from pig lung. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Growth factor and pro-inflammatory cytokine contents in platelet-rich plasma (PRP), plasma rich in growth factors (PRGF), advanced platelet-rich fibrin (A-PRF), and concentrated growth factors (CGF).

PubMed

Masuki, Hideo; Okudera, Toshimitsu; Watanebe, Taisuke; Suzuki, Masashi; Nishiyama, Kazuhiko; Okudera, Hajime; Nakata, Koh; Uematsu, Kohya; Su, Chen-Yao; Kawase, Tomoyuki

2016-12-01

The development of platelet-rich fibrin (PRF) drastically simplified the preparation procedure of platelet-concentrated biomaterials, such as platelet-rich plasma (PRP), and facilitated their clinical application. PRF's clinical effectiveness has often been demonstrated in pre-clinical and clinical studies; however, it is still controversial whether growth factors are significantly concentrated in PRF preparations to facilitate wound healing and tissue regeneration. To address this matter, we performed a comparative study of growth factor contents in PRP and its derivatives, such as advanced PRF (A-PRF) and concentrated growth factors (CGF). PRP and its derivatives were prepared from the same peripheral blood samples collected from healthy donors. A-PRF and CGF preparations were homogenized and centrifuged to produce extracts. Platelet and white blood cell counts in A-PRF and CGF preparations were determined by subtracting those counts in red blood cell fractions, supernatant acellular serum fractions, and A-PRF/CGF exudate fractions from those counts of whole blood samples. Concentrations of growth factors (TGF-β1, PDGF-BB, VEGF) and pro-inflammatory cytokines (IL-1β, IL-6) were determined using ELISA kits. Compared to PRP preparations, both A-PRF and CGF extracts contained compatible or higher levels of platelets and platelet-derived growth factors. In a cell proliferation assay, both A-PRF and CGF extracts significantly stimulated the proliferation of human periosteal cells without significant reduction at higher doses. These data clearly demonstrate that both A-PRF and CGF preparations contain significant amounts of growth factors capable of stimulating periosteal cell proliferation, suggesting that A-PRF and CGF preparations function not only as a scaffolding material but also as a reservoir to deliver certain growth factors at the site of application.

Implementation of secondary bacterial culture testing of platelets to mitigate residual risk of septic transfusion reactions.

PubMed

Bloch, Evan M; Marshall, Christi E; Boyd, Joan S; Shifflett, Lisa; Tobian, Aaron A R; Gehrie, Eric A; Ness, Paul M

2018-04-01

Bacterial contamination of platelets remains a major transfusion-associated risk despite long-standing safety measures in the United States. We evaluated an approach using secondary bacterial culture (SBC) to contend with residual risk of bacterial contamination. Phased implementation of SBC was initiated in October 2016 for platelets (all apheresis collected) received at our institution from the blood donor center (Day 3 post collection). Platelet products were sampled aseptically (5 mL inoculated into an aerobic bottle [BacT/ALERT BPA, BioMerieux, Inc.]) by the blood bank staff upon receipt, using a sterile connection device and sampling kit. The platelet sample was inoculated into an aerobic blood culture bottle and incubated at 35°C for 3 days. The cost of SBC was calculated on the basis of consumables and labor costs at time of implementation. In the 13 months following implementation (October 6, 2016, to November 30, 2017), 23,044/24,653 (93.47%) platelet products underwent SBC. A total of eight positive cultures were detected (incidence 1 in 2881 platelet products), seven of which were positive within 24 hours of SBC. Coagulase negative Staphyloccus spp. were identified in four cases. Five of the eight cases were probable true positive (repeat reactive) and interdicted (cost per averted case was US$77,935). The remaining three cases were indeterminate. No septic transfusion reactions were reported during the observation period. We demonstrate the feasibility of SBC of apheresis platelets to mitigate bacterial risk. SBC is lower cost than alternative measures (e.g., pathogen reduction and point-of-release testing) and can be integrated into workflow at hospital transfusion services. © 2018 AABB.

Erythrocyte sedimentation rate and fibrinogen concentration of whole blood influences the cellular composition of platelet-rich plasma obtained from centrifugation methods.

PubMed

Yin, Wenjing; Xu, Zhengliang; Sheng, Jiagen; Xie, Xuetao; Zhang, Changqing

2017-09-01

Erythrocyte sedimentation rate (ESR), which reflects the sedimentation rate of platelets, leukocytes and erythrocytes in response to centrifugal force, may influence the cellular composition of platelet-rich plasma (PRP) obtained via centrifugation methods. However, no relevant studies have substantiated this. In the present study, blood was collected from 40 healthy volunteers and used to prepare PRP with two plasma-based preparation systems [YinPRP and Plasma Rich in Growth Factor (PRGF) systems] and two buffy coat-based systems (RegenPRP and WEGOPRP systems) in a single-donor model. Volumes of PRP and platelet-poor plasma (PPP) that were removed in the preparation process were recorded. Analyses of ESR, haematocrit, C-reaction protein, coagulation, serum glucose and serum lipid of the whole blood used for PRP preparation were performed to evaluate the levels of ESR and the factors known to influence it. Whole blood analysis was performed to evaluate the cellular composition of PRP. Results demonstrated that there were marked positive correlations between the ESR of the whole blood used for PRP preparation and PPP removal efficiencies, platelet concentrations, platelet capture efficiencies and platelet enrichment factors of PRP formulations obtained from plasma-based systems, and PRP yield efficiency of RegenPRP and PPP removal efficiency of WEGOPRP. Furthermore, there were marked negative correlations between ESR and concentrations and enrichment factors of platelets, leukocytes and erythrocytes of RegenPRP. Fibrinogen concentration of the whole blood, which had a marked positive correlation with ESR, also influenced the cellular composition of PRP. These findings may increase the understanding of PRP preparation and provide substantial evidence for the individualised optimisation of PRP preparation systems used in clinical practice.

Why Do Blood Donors Lapse or Reduce Their Donation's Frequency?

PubMed

Charbonneau, Johanne; Cloutier, Marie-Soleil; Carrier, Élianne

2016-01-01

Finding effective ways to retain blood donors is crucial. This study seeks to compare, in a context of a voluntary and nonremunerated system, donor demographics and deterrents to blood donation among plasma/platelet donors (PPDs), regular whole blood donors (WBDs), and lapsed whole blood donors (LWBD). Among 1879 participants to a survey on motivations, time use, and blood donation, 207 WBDs (26%) and 148 PPDs (31%) said that they reduced their donation frequency over the last 5 years. Participants to this survey also included 609 LWBDs, who did not donate in the past 5 years. We asked about reasons why they reduce or cease to donate blood and demographic variables. χ(2) Tests were completed to determine which deterrents stand out across the 3 blood donor groups. The deterrent indicating the highest percentage was "time constraints related to work or studies" (43% for all respondents). Comparison of WBDs, LWBDs, and PPDs shows that results for 7 deterrents were statistically different between the 3 groups. Obstacles to donating blood also vary based on sex, age (life course), and level of education. Blood collection agencies should consider developing new retention strategies tailored to blood donors, taking into account the specific profiles of female/male donors, events that typically occur at various stages of life, and particular challenges associated with differences in levels of education. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Platelet Aggregometry Testing: Molecular Mechanisms, Techniques and Clinical Implications

PubMed Central

Koltai, Katalin; Kesmarky, Gabor; Feher, Gergely; Tibold, Antal

2017-01-01

Platelets play a fundamental role in normal hemostasis, while their inherited or acquired dysfunctions are involved in a variety of bleeding disorders or thrombotic events. Several laboratory methodologies or point-of-care testing methods are currently available for clinical and experimental settings. These methods describe different aspects of platelet function based on platelet aggregation, platelet adhesion, the viscoelastic properties during clot formation, the evaluation of thromboxane metabolism or certain flow cytometry techniques. Platelet aggregometry is applied in different clinical settings as monitoring response to antiplatelet therapies, the assessment of perioperative bleeding risk, the diagnosis of inherited bleeding disorders or in transfusion medicine. The rationale for platelet function-driven antiplatelet therapy was based on the result of several studies on patients undergoing percutaneous coronary intervention (PCI), where an association between high platelet reactivity despite P2Y12 inhibition and ischemic events as stent thrombosis or cardiovascular death was found. However, recent large scale randomized, controlled trials have consistently failed to demonstrate a benefit of personalised antiplatelet therapy based on platelet function testing. PMID:28820484

PARot – assessing platelet-rich plasma plus arthroscopic subacromial decompression in the treatment of rotator cuff tendinopathy: study protocol for a randomized controlled trial

PubMed Central

2013-01-01

Background Platelet-rich plasma (PRP) is an autologous platelet concentrate. It is prepared by separating the platelet fraction of whole blood from patients and mixing it with an agent to activate the platelets. In a clinical setting, PRP may be reapplied to the patient to improve and hasten the healing of tissue. The therapeutic effect is based on the presence of growth factors stored in the platelets. Current evidence in orthopedics shows that PRP applications can be used to accelerate bone and soft tissue regeneration following tendon injuries and arthroplasty. Outcomes include decreased inflammation, reduced blood loss and post-treatment pain relief. Recent shoulder research indicates there is poor vascularization present in the area around tendinopathies and this possibly prevents full healing capacity post surgery (Am J Sports Med36(6):1171–1178, 2008). Although it is becoming popular in other areas of orthopedics there is little evidence regarding the use of PRP for shoulder pathologies. The application of PRP may help to revascularize the area and consequently promote tendon healing. Such evidence highlights an opportunity to explore the efficacy of PRP use during arthroscopic shoulder surgery for rotator cuff pathologies. Methods/Design PARot is a single center, blinded superiority-type randomized controlled trial assessing the clinical outcomes of PRP applications in patients who undergo shoulder surgery for rotator cuff disease. Patients will be randomized to one of the following treatment groups: arthroscopic subacromial decompression surgery or arthroscopic subacromial decompression surgery with application of PRP. The study will run for 3 years and aims to randomize 40 patients. Recruitment will be for 24 months with final follow-up at 1 year post surgery. The third year will also involve collation and analysis of the data. This study will be funded through the NIHR Biomedical Research Unit at the Oxford University Hospitals NHS Trust. Trial registration Current Controlled Trials: ISRCTN10464365 PMID:23758981

Advanced platelet-rich fibrin: a new concept for cell-based tissue engineering by means of inflammatory cells.

PubMed

Ghanaati, Shahram; Booms, Patrick; Orlowska, Anna; Kubesch, Alica; Lorenz, Jonas; Rutkowski, Jim; Landes, Constantin; Sader, Robert; Kirkpatrick, Cj; Choukroun, Joseph

2014-12-01

Choukroun's platelet-rich fibrin (PRF) is obtained from blood without adding anticoagulants. In this study, protocols for standard platelet-rich fibrin (S-PRF) (2700 rpm, 12 minutes) and advanced platelet-rich fibrin (A-PRF) (1500 rpm, 14 minutes) were compared to establish by histological cell detection and histomorphometrical measurement of cell distribution the effects of the centrifugal force (speed and time) on the distribution of cells relevant for wound healing and tissue regeneration. Immunohistochemistry for monocytes, T and B -lymphocytes, neutrophilic granulocytes, CD34-positive stem cells, and platelets was performed on clots produced from four different human donors. Platelets were detected throughout the clot in both groups, although in the A-PRF group, more platelets were found in the distal part, away from the buffy coat (BC). T- and B-lymphocytes, stem cells, and monocytes were detected in the surroundings of the BC in both groups. Decreasing the rpm while increasing the centrifugation time in the A-PRF group gave an enhanced presence of neutrophilic granulocytes in the distal part of the clot. In the S-PRF group, neutrophils were found mostly at the red blood cell (RBC)-BC interface. Neutrophilic granulocytes contribute to monocyte differentiation into macrophages. Accordingly, a higher presence of these cells might be able to influence the differentiation of host macrophages and macrophages within the clot after implantation. Thus, A-PRF might influence bone and soft tissue regeneration, especially through the presence of monocytes/macrophages and their growth factors. The relevance and feasibility of this tissue-engineering concept have to be proven through in vivo studies.

Evaluation of flow cytometric HIT assays in relation to an IgG-Specific immunoassay and clinical outcome.

PubMed

Kerényi, Adrienne; Beke Debreceni, Ildikó; Oláh, Zsolt; Ilonczai, Péter; Bereczky, Zsuzsanna; Nagy, Béla; Muszbek, László; Kappelmayer, János

2017-09-01

Heparin-induced thrombocytopenia (HIT) is a severe side effect of heparin treatment caused by platelet activating IgG antibodies generated against the platelet factor 4 (PF4)-heparin complex. Thrombocytopenia and thrombosis are the leading clinical symptoms of HIT. The clinical pretest probability of HIT was evaluated by the 4T score system. Laboratory testing of HIT was performed by immunological detection of antibodies against PF4-heparin complex (EIA) and two functional assays. Heparin-dependent activation of donor platelets by patient plasma was detected by flow cytometry. Increased binding of Annexin-V to platelets and elevated number of platelet-derived microparticles (PMP) were the indicators of platelet activation. EIA for IgG isotype HIT antibodies was performed in 405 suspected HIT patients. Based on negative EIA results, HIT was excluded in 365 (90%) of cases. In 40 patients with positive EIA test result functional tests were performed. Platelet activating antibodies were detected in 17 cases by Annexin V binding. PMP count analysis provided nearly identical results. The probability of a positive flow cytometric assay result was higher in patients with elevated antibody titer. 71% of patients with positive EIA and functional assay had thrombosis. EIA is an important first line laboratory test in the diagnosis of HIT; however, HIT must be confirmed by a functional test. Annexin V binding and PMP assays using flow cytometry are functional HIT tests convenient in a clinical diagnostic laboratory. The positive results of functional assays may predict the onset of thrombosis. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

Generation of Platelet Microparticles after Cryopreservation of Apheresis Platelet Concentrates Contributes to Hemostatic Activity.

PubMed

Eker, İbrahim; Yılmaz, Soner; Çetinkaya, Rıza Aytaç; Pekel, Aysel; Ünlü, Aytekin; Gürsel, Orhan; Yılmaz, Sebahattin; Avcu, Ferit; Muşabak, Uğur; Pekoğlu, Ahmet; Ertaş, Zerrin; Açıkel, Cengizhan; Zeybek, Nazif; Kürekçi, Ahmet Emin; Avcı, İsmail Yaşar

2017-03-01

In the last decade, substantial evidence has accumulated about the use of cryopreserved platelet concentrates, especially in trauma. However, little reference has been made in these studies to the morphological and functional changes of platelets. Recently platelets have been shown to be activated by cryopreservation processes and to undergo procoagulant membrane changes resulting in the generation of platelet-derived microparticles (PMPs), platelet degranulation, and release of platelet-derived growth factors (PDGFs). We assessed the viabilities and the PMP and PDGF levels of cryopreserved platelets, and their relation with thrombin generation. Apheresis platelet concentrates (APCs) from 20 donors were stored for 1 day and cryopreserved with 6% dimethyl sulfoxide. Cryopreserved APCs were kept at -80 °C for 1 day. Thawed APCs (100 mL) were diluted with 20 mL of autologous plasma and specimens were analyzed for viabilities and PMPs by flow cytometry, for thrombin generation by calibrated automated thrombogram, and for PDGFs by enzyme-linked immunosorbent assay testing. The mean PMP and PDGF levels in freeze-thawed APCs were significantly higher (2763±399.4/µL vs. 319.9±80.5/µL, p<0.001 and 550.9±73.6 pg/mL vs. 96.5±49 pg/mL, p<0.001, respectively), but the viability rates were significantly lower (68.2±13.7% vs. 94±7.5%, p<.001) than those of fresh APCs. The mean endogenous thrombin potential (ETP) of freeze-thawed APCs was significantly higher than that of the fresh APCs (3406.1±430.4 nM.min vs. 2757.6±485.7 nM.min, p<0.001). Moreover, there was a significant positive poor correlation between ETP levels and PMP levels (r=0.192, p=0.014). Our results showed that, after cryopreservation, while levels of PMPs were increasing, significantly higher and earlier thrombin formation was occurring in the samples analyzed despite the significant decrease in viability. Considering the damage caused by the freezing process and the scarcity of evidence for their in vivo superiority, frozen platelets should be considered for use in austere environments, reserving fresh platelets for prophylactic use in blood banks.

VERifyNow in DIabetes high-on-treatment platelet reactivity: a pharmacodynamic study on switching from clopidogrel to prasugrel.

PubMed

Cubero Gómez, José M; Acosta Martínez, Juan; Mendias Benítez, Crsitina; Díaz De La Llera, Luis S; Fernández-Quero, Mónica; Guisado Rasco, Agustí; Villa Gil-Ortega, Manuel; Sánchez González, Ángel

2015-12-01

Diabetic patients with an acute coronary syndrome undergoing percutaneous coronary intervention frequently exhibit high platelet reactivity while on clopidogrel. We hypothesized that in diabetic patients undergoing percutaneous coronary intervention, who exhibit high-platelet-reactivity after standard treatment with clopidogrel, a 60-mg prasugrel loading dose is superior to standard treatment with clopidogrel for optimal P2Y12 inhibition within the first 24-36 h post-angioplasty. VERDI was a prospective, randomized, single-centre, single-blind, parallel-design study (NCT01684813). Consecutive diabetic patients with an non-ST-segment elevation acute coronary syndrome undergoing percutaneous coronary intervention and loaded with clopidogrel were considered for platelet reactivity assessment immediately before angioplasty with the VerifyNow assay measured in P2Y12 reaction units (PRU). Fifty of 63 screened patients (79.4%) had high platelet reactivity (PRU ≥ 208) and were randomized to receive a 60-mg prasugrel loading dose (n = 25) versus clopidogrel standard dose (n = 25). Platelet function was assessed again 24 hours post-angioplasty. Prasugrel achieved greater platelet inhibition than clopidogrel 24 hours post-angioplasty (median [interquartile range], 38 [9-72] vs 285 [240-337], respectively; P < 0.001). The non-high-platelet-reactivity rate (PRU < 208) at 24 h post-angioplasty (primary end point) was higher with prasugrel; 25 patients (100%) in the prasugrel group achieved optimal antiaggregation vs 4 patients (16%) in the clopidogrel group (P < 0.001). No significant acute bleeding was documented in either group. Among type 2 diabetic patients suffering an acute coronary syndrome with high-platelet-reactivity undergoing percutaneous coronary intervention, switching from clopidogrel to prasugrel was superior to standard treatment with clopidogrel for the achievement of optimal antiaggregation within the first 24 hours post-angioplasty.

Short-term in vivo modifications of platelet NADPH oxidase 2 (NOX2) and prostaglandin F2α in HIV-1 patients on abacavir-based therapies.

PubMed

Pastori, D; Esposito, A; Carnevale, R; Bartimoccia, S; Nocella, C; Fantauzzi, A; Pignatelli, P; Violi, F; Mezzaroma, I

2016-11-01

The aim of the study was to investigate the in vivo effect of abacavir (ABC) on platelet oxidative stress. We performed a randomized pilot study including 39 HIV-1-infected patients, 17 on zidovudine/lamivudine (ZDV/3TC) and 22 on tenofovir/emtricitabine (TDF/FTC). Ten patients on ZDV/3TC and eight patients on TDF/FTC were randomly allocated to switching the nucleoside backbone to ABC/3TC. At baseline and after 6 months, platelet oxidative stress was assessed by platelet NADPH oxidase 2 (NOX2)-derived peptide (sNOX2-dp), a marker of NOX2 activation, and platelet prostaglandin F 2α (8-iso-PGF 2α ). Platelet activation was measured by soluble CD40L (sCD40L). At baseline, no differences between ZDV/3TC or TDF/FTC recipients were found. After 6 months, patients switching from ZDV/3TC showed a decrease of sNOX2-dp (from 20.9±5.7 to 12.5±3.8 pg/ml, p=0.002) and 8-iso-PGF 2α (from 154.3±41.9 to 122.9±28.0 pmol/l, p=0.025). No effects on platelet oxidative stress biomarkers were observed in subjects from TDF/FTC, who showed a significant increase in blood glucose (p=0.043) and total cholesterol (p=0.027). ABC showed no effect on sCD40L levels in both groups. ABC reduced platelet sNOX2-dp and 8-iso-PGF 2α in HIV-1 subjects switching from ZDV/3TC but not in those from TDF/FTC after 6 months. No changes in platelet activation were found in both groups. © 2016 British HIV Association.

Magnetically-assembled micro/mesopixels exhibiting light intensity enhancement in the (012) planes of fish guanine crystals

NASA Astrophysics Data System (ADS)

Chikashige, T.; Iwasaka, M.

2018-05-01

In this study, a new method was investigated to form light-reflecting dots at the micrometer scale using the magnetic orientations of biogenic guanine crystals obtained from fish skin and scales. The crystal platelets, possessing average dimensions of 5 μm×20 μm×100 nm, were dispersed in water and observed during exposure to vertical magnetic fields up to 5 T. The magnetic field direction was parallel to Earth's gravity, and allowed the narrowest edges of the crystals to be observed at the micrometer scale for the first time. The magnetic orientation process was initiated under conditions where the crystal platelets in water were laid on a glass substrate or where the platelets had random orientations. In the former case, the crystal platelets followed a two-stage magnetic orientation process where, in the first step, the platelet widths were aligned in the magnetic field direction. The second step required rotation of the ˜20-μm-long plates with respect to the Earth's gravity, where application of a 5 T magnetic field enabled their orientation. Real-time images of the magnetically aligning platelets provided new evidence that the crystal platelets also emitted reflected light from a very narrow window at two crystal planes (i.e., (0 1 ¯ 2 ¯ ) and (0 1 ¯ 2 )). In the latter case with random platelet orientation, spatially-condensed light-reflecting dots appeared while the guanine crystal platelets were floating and maintaining their orientation. The technique developed for controlling light-reflecting microscale objects in an aqueous medium can be applied to produce a type of microfluidic optical tool.

A second-generation blood substitute (perfluorodichlorooctane emulsion) does not activate complement during an ex vivo circulation model of bypass.

PubMed

Rosoff, J D; Soltow, L O; Vocelka, C R; Schmer, G; Chandler, W L; Cochran, R P; Kunzelman, K S; Spiess, B D

1998-08-01

To examine whether a second-generation perfluorocarbon (PFC) blood substitute added to the cardiopulmonary bypass (CPB) prime influences complement production. A prospective, randomized, single-blinded, ex vivo model. A university hospital, laboratory, and clinics. Ten healthy adult consented volunteer blood donors (five men, five women). Ex vivo closed-loop extracorporeal circuit including membrane oxygenator, tubing, and filter primed with crystalloid or crystalloid plus PFC was circulated for 1 hour with the addition of 500 mL of heparinized fresh human whole blood. Laboratory specimens were drawn from the circuit at 10-minute intervals for 1 hour and measured for complement (C3a, Bb fragment) concentrations, blood gases, fibrinogen concentration, platelet count, and hematocrit. In the PFC group, C3a and Bb fragments were equal to or less than those in the group that received crystalloid alone. The second-generation PFC added to the prime of a CPB circuit does not independently increase complement production.

Molecular blood grouping of donors.

PubMed

St-Louis, Maryse

2014-04-01

For many decades, hemagglutination has been the sole means to type blood donors. Since the first blood group gene cloning in the early 1990s, knowledge on the molecular basis of most red blood cell, platelet and neutrophil antigens brought the possibility of using nucleotide-based techniques to predict phenotype. This review will summarized methodologies available to genotype blood groups from laboratory developed assays to commercially available platforms, and how proficiency assays become more present. The author will also share her vision of the transfusion medicine future. The field is presently at the crossroads, bringing new perspectives to a century old practice. Copyright © 2014 Elsevier Ltd. All rights reserved.

Flavan-3-ol-enriched dark chocolate and white chocolate improve acute measures of platelet function in a gender-specific way--a randomized-controlled human intervention trial.

PubMed

Ostertag, Luisa M; Kroon, Paul A; Wood, Sharon; Horgan, Graham W; Cienfuegos-Jovellanos, Elena; Saha, Shikha; Duthie, Garry G; de Roos, Baukje

2013-02-01

We examined whether flavan-3-ol-enriched dark chocolate, compared with standard dark and white chocolate, beneficially affects platelet function in healthy subjects, and whether this relates to flavan-3-ol bioavailability. A total of 42 healthy subjects received an acute dose of flavan-3-ol-enriched dark, standard dark or white chocolate, in random order. Blood and urine samples were obtained just before and 2 and 6 h after consumption for measurements of platelet function, and bioavailability and excretion of flavan-3-ols. Flavan-3-ol-enriched dark chocolate significantly decreased adenosine diphosphate-induced platelet aggregation and P-selectin expression in men (all p ≤ 0.020), decreased thrombin receptor-activating peptide-induced platelet aggregation and increased thrombin receptor-activating peptide-induced fibrinogen binding in women (both p ≤ 0.041), and increased collagen/epinephrine-induced ex vivo bleeding time in men and women (p ≤ 0.042). White chocolate significantly decreased adenosine diphosphate-induced platelet P-selectin expression (p = 0.002) and increased collagen/epinephrine-induced ex vivo bleeding time (p = 0.042) in men only. Differences in efficacy by which flavan-3-ols affect platelet function were only partially explained by concentrations of flavan-3-ols and their metabolites in plasma or urine. Flavan-3-ols in dark chocolate, but also compounds in white chocolate, can improve platelet function, dependent on gender, and may thus beneficially affect atherogenesis. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Effect of Perioperative Immunonutrition on the Phagocytic Activity of Blood Platelets in Advanced Gastric Cancer Patients

PubMed Central

Kamocki, Zbigniew; Gryko, Mariusz; Kedra, Boguslaw; Kemona, Halina

2013-01-01

Background and Aims. Perioperative immunonutrition can influence the phagocytic activity of platelets in advanced gastric cancer. Methods. 51 patients with stage IV gastric cancer divided into four groups depending on the clinical status and 40 normal donors were analyzed. Patients of groups I and II underwent palliative gastrectomy. Patients of groups III and IV had exploratory laparotomy. Perioperative immunonutrition was administered as follows: group I—TPN, II—oral arginine, peripheral TPN, III—TPN preoperatively, and IV—without nutrition. The phagocytic activity of blood platelets was determined before and after nutritional therapy and was assessed by measuring the fraction of phagocytic thrombocytes (%phag) and the phagocytic index (Ixphag). Results. The percentage of phagocytizing platelets and the phagocytic index prior to and after the surgery amounted to the following: group I—1.136–1.237, P = NS, and 1.007–1.1, P = NS, respectively, II—1.111–1.25, P < 0.05, and 1.011–1.083, P < 0.05, III—1.112–1.186, P = NS, and 0.962–1.042, P = NS, and IV—1.085–0.96, P = NS, and 1.023–1.04, P = NS. Conclusions. The phagocytic activity of platelets in patients with advanced gastric cancer is significantly impaired. Perioperative immunonutrition with oral arginine-rich diet can partially improve the phagocytic activity of blood platelets. This trial is registred with Clinicaltrials.gov-NCT01704664. PMID:24363760

Tunneling Conductivity and Piezoresistivity of Composites Containing Randomly Dispersed Conductive Nano-Platelets

PubMed Central

Oskouyi, Amirhossein Biabangard; Sundararaj, Uttandaraman; Mertiny, Pierre

2014-01-01

In this study, a three-dimensional continuum percolation model was developed based on a Monte Carlo simulation approach to investigate the percolation behavior of an electrically insulating matrix reinforced with conductive nano-platelet fillers. The conductivity behavior of composites rendered conductive by randomly dispersed conductive platelets was modeled by developing a three-dimensional finite element resistor network. Parameters related to the percolation threshold and a power-low describing the conductivity behavior were determined. The piezoresistivity behavior of conductive composites was studied employing a reoriented resistor network emulating a conductive composite subjected to mechanical strain. The effects of the governing parameters, i.e., electron tunneling distance, conductive particle aspect ratio and size effects on conductivity behavior were examined. PMID:28788580

Update: Acute coronary syndromes (V). Personalized antiplatelet therapy.

PubMed

Gurbel, Paul A; Rafeedheen, Rahil; Tantry, Udaya S

2014-06-01

It is well established that high on-treatment platelet reactivity to adenosine diphosphate during clopidogrel therapy is an independent risk factor for ischemic event occurrences in a postpercutaneous coronary intervention patients. However, the precise role of platelet function testing remains debated. Platelet function testing to ensure optimal platelet inhibition has been recommended by some authorities to improve outcomes in patients treated with clopidogrel. Recent prospective, randomized trials of personalized antiplatelet therapy have failed to demonstrate a benefit of platelet function testing in improving outcomes. In this review article, we discuss the mechanisms responsible for clopidogrel nonreponsiveness, recent trials of platelet function testing, and other new developments in the field of personalized antiplatelet therapy. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Platelet-rich plasma in arthroscopic rotator cuff repair: a meta-analysis of randomized controlled trials.

PubMed

Zhao, Jia-Guo; Zhao, Li; Jiang, Yan-Xia; Wang, Zeng-Liang; Wang, Jia; Zhang, Peng

2015-01-01

The purpose of this study was to appraise the retear rate and clinical outcomes of platelet-rich plasma use in patients undergoing arthroscopic full-thickness rotator cuff repair. We searched the Cochrane Library, PubMed, and EMBASE databases for randomized controlled trials comparing the outcomes of arthroscopic rotator cuff surgery with or without the use of platelet-rich plasma. Methodological quality was assessed by the Detsky quality scale. When there was no high heterogeneity, we used a fixed-effects model. Dichotomous variables were presented as risk ratios (RRs) with 95% confidence intervals (CIs), and continuous data were measured as mean differences with 95% CIs. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used to assess the quality of evidence for each individual outcome. Eight randomized controlled trials were included, with the sample size ranging from 28 to 88. Overall methodological quality was high. Fixed-effects analysis showed that differences were not significant between the 2 groups in retear rate (RR, 0.94; 95% CI, 0.70 to 1.25; P = .66), Constant score (mean difference, 1.12; 95% CI, -1.38 to 3.61; P = .38), and University of California at Los Angeles (UCLA) score (mean difference, -0.68; 95% CI, -2.00 to 0.65; P = .32). The strength of GRADE evidence was categorized respectively as low for retear, moderate for Constant score, and low for UCLA shoulder score. Our meta-analysis does not support the use of platelet-rich plasma in the arthroscopic repair of full-thickness rotator cuff tears over repairs without platelet-rich plasma because of similar retear rates and clinical outcomes. Level II, meta-analysis of Level I and II randomized controlled trials. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

A Prospective, Randomized, Open-Label, Blinded, Endpoint Study Exploring Platelet Response to Half-Dose Prasugrel and Ticagrelor in Patients with the Acute Coronary Syndrome: HOPE-TAILOR Study.

PubMed

Jin, Cai De; Kim, Moo Hyun; Bang, Junghee; Serebruany, Victor

The optimal dosing of novel oral P2Y12 receptor platelet inhibitors such as prasugrel or ticagrelor is unclear and especially challenging in East Asians. We hypothesize that half-dose prasugrel and ticagrelor may be sufficient for long-term maintenance management in Korean patients with the acute coronary syndrome (ACS) compared with conventional dosages. HOPE-TAILOR (Half Dose of Prasugrel and Ticagrelor in Platelet Response after Acute Coronary Syndromes) is a prospective, randomized, open-label, blinded, endpoint (PROBE) single-center, clinical trial. A total of 100 patients with ACS undergoing drug-eluting stent implantation will be randomly assigned to prasugrel, ticagrelor, or clopidogrel, and the patients in each treatment group will receive 1-month therapy with 100 mg q.d. aspirin plus prasugrel 10 mg q.d., ticagrelor 90 mg b.i.d., or clopidogrel 75 mg q.d., followed by half-dose prasugrel 5 mg q.d. or ticagrelor 45 mg b.i.d. for maintenance treatment but without clopidogrel dose reduction. The primary endpoint will be optimal platelet reactivity 3 months after coronary intervention, defined by VerifyNow Analyzer (PRU: 85-208) and vasodilator-stimulated phosphoprotein P2Y12 flow cytometry assay (platelet reactivity indices: 16-50%). Clinical outcomes will also be assessed, including major efficacy (composite of cardiac death, nonfatal myocardial infarction, repeat revascularization, or stroke) and safety (bleeding ≥2 according to the Bleeding Academic Research Consortium). HOPE-TAILOR is a prospective, randomized, open-label, blinded, endpoint study to explore the efficacy and safety of novel P2Y12 receptor inhibitors administered orally at half the dose in Korean patients with ACS. The results will be available late in 2017. © 2017 S. Karger AG, Basel.

Validation of the FIB-4 index for evaluation of fibrosis in patients with recurrent hepatitis C after living donor liver transplantation: A single center experience.

PubMed

Kitajima, Toshihiro; Kaido, Toshimi; Hamaguchi, Yuhei; Yagi, Shintaro; Taura, Kojiro; Fujimoto, Yasuhiro; Hatano, Etsuro; Okajima, Hideaki; Haga, Hironori; Uemoto, Shinji

2016-07-01

The FIB-4 index has been proposed as a simple, non-invasive surrogate marker of liver fibrosis in patients with hepatitis C virus (HCV). However, the utility of FIB-4 in HCV positive patients after living donor liver transplantation (LDLT) has not been assessed. The aim of this study was to evaluate the efficacy of FIB-4 in the detection of significant liver graft fibrosis caused by recurrent HCV infection after LDLT compared with other simple fibrosis markers. A total of 259 liver biopsies (LB) with evidence of recurrent HCV were taken from 110 HCV positive LDLT patients who had undergone concomitant splenectomy before administration of antiviral therapy. In LB performed at 3 months or later after LT (n = 202, subject group), FIB-4 was compared between fibrosis stages and the accuracy of FIB-4 in predicting significant fibrosis (METAVIR, F ≥ 2) was assessed compared with aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio, age-platelet index, and AST to platelet ratio index (APRI). FIB-4 was significantly different between all fibrosis stages (F0 and F1-F4, P = 0.022; F0/1 and F2-F4, P < 0.0005; and F0-F2 and F3F4, P = 0.034) and provided the best area under the receiver-operator curve (AUROC) compared with other markers (FIB-4, 0.711; APRI, 0.693; age-platelet index, 0.663; and AST to ALT ratio, 0.562). The optimal cut-off value to identify significant fibrosis was 2.20 with 65% sensitivity and 69% specificity. FIB-4 is a more reliable marker for diagnosing significant liver fibrosis than APRI, age-platelet index, and AST to ALT ratio in LDLT patients with HCV. © 2015 The Japan Society of Hepatology.

A randomized controlled trial of aspirin and exertional heat stress activation of platelets in firefighters during exertion in thermal protective clothing.

PubMed

Hostler, David; Suyama, Joe; Guyette, Francis X; Moore, Charity G; Pryor, Riana R; Khorana, Priya; McEntire, Serina J; Comer, Diane; Reis, Steven E

2014-01-01

Platelet aggregation is enhanced in firefighters following short bouts of work in thermal protective clothing (TPC). We sought to determine if aspirin therapy before and/or following exertion in TPC prevents platelet activation. In a double-blind, placebo-controlled study, 102 firefighters were randomized to receive daily therapy (81 mg aspirin or placebo) for 14 days before and a single dose (325 mg aspirin or placebo) following exercise in TPC resulting in four potential assignments: aspirin before and after exercise (AA), placebo before and after exercise (PP), aspirin before and placebo after exercise (AP), and placebo before and aspirin after exercise (PA). Platelet closure time (PCT) was measured with a platelet function analyzer before the 2-week treatment, after the 2 week treatment period, immediately after exercise, and 30, 60, and 90 minutes later. Baseline PCT did not differ between groups. PCT changed over time in all four groups (p < 0.001) rising to a median of >300 seconds [IQR 99, 300] in AA and >300 [92, 300] in AP prior to exercise. Following exercise, median PCT decreased to in all groups. Median PCT returned to >300 seconds 30 minutes later in AA and AP and rose to 300 seconds in PA 60 minutes after exercise. Daily aspirin therapy blunts platelet activation during exertional heat stress and single-dose aspirin therapy following exertional heat stress reduces platelet activation within 60 minutes.

Comparison of growth factor and platelet concentration from commercial platelet-rich plasma separation systems.

PubMed

Castillo, Tiffany N; Pouliot, Michael A; Kim, Hyeon Joo; Dragoo, Jason L

2011-02-01

Clinical studies claim that platelet-rich plasma (PRP) shortens recovery times because of its high concentration of growth factors that may enhance the tissue repair process. Most of these studies obtained PRP using different separation systems, and few analyzed the content of the PRP used as treatment. This study characterized the composition of single-donor PRP produced by 3 commercially available PRP separation systems. Controlled laboratory study. Five healthy humans donated 100 mL of blood, which was processed to produce PRP using 3 PRP concentration systems (MTF Cascade, Arteriocyte Magellan, Biomet GPS III). Platelet, white blood cell (WBC), red blood cell, and fibrinogen concentrations were analyzed by automated systems in a clinical laboratory, whereas ELISA determined the concentrations of platelet-derived growth factor αβ and ββ (PDGF-αβ, PDGF-ββ), transforming growth factor β1 (TGF-β1), and vascular endothelial growth factor (VEGF). There was no significant difference in mean PRP platelet, red blood cell, active TGF-β1, or fibrinogen concentrations among PRP separation systems. There was a significant difference in platelet capture efficiency. The highest platelet capture efficiency was obtained with Cascade, which was comparable with Magellan but significantly higher than GPS III. There was a significant difference among all systems in the concentrations of WBC, PDGF-αβ, PDGF-ββ, and VEGF. The Cascade system concentrated leukocyte-poor PRP, compared with leukocyte-rich PRP from the GPS III and Magellan systems. The GPS III and Magellan concentrate leukocyte-rich PRP, which results in increased concentrations of WBCs, PDGF-αβ, PDGF-ββ, and VEGF as compared with the leukocyte-poor PRP from Cascade. Overall, there was no significant difference among systems in the platelet concentration, red blood cell, active TGF-β1, or fibrinogen levels. Products from commercially available PRP separation systems produce differing concentrations of growth factors and WBCs. Further research is necessary to determine the clinical relevance of these findings.

Steam-cooking rapidly destroys and reverses onion-induced antiplatelet activity

PubMed Central

2012-01-01

Background Foods in the diet that can aid in the prevention of diseases are of major interest. Onions are key ingredients in many cuisines around the world and moreover, onion demand has trended higher over the past three decades. An important pharmacological aspect of onion is the ability to inhibit platelet aggregation. Raw onions inhibit platelet aggregation; however, when onions are boiled or heated, antiplatelet activity may be abolished. Methods Onion quarters were steamed for 0, 1, 3, 6, 10, and 15 min. The in vitro antiplatelet activity of a yellow hybrid storage onion was examined at these times on the blood of 12 human subjects using in vitro whole blood aggregometry. Results Contrary to findings reported for boiling, antiplatelet activity was destroyed between 3 and 6 min of steaming, and at 10 min of steaming, cooked onions stimulated platelet activity. Extracts from cooked onion had the potential to reverse the inhibitory effect on blood platelets by 25%. Responses were consistent across all donors. Total polyphenolic concentration and soluble solids were not affected by steaming time. Conclusions The potential value of cooked onion preparations may result in destruction or reversal of antiplatelet activity, without affecting the polyphenolic concentration. PMID:22992282

Steam-cooking rapidly destroys and reverses onion-induced antiplatelet activity.

PubMed

Hansen, Emilie A; Folts, John D; Goldman, Irwin L

2012-09-20

Foods in the diet that can aid in the prevention of diseases are of major interest. Onions are key ingredients in many cuisines around the world and moreover, onion demand has trended higher over the past three decades. An important pharmacological aspect of onion is the ability to inhibit platelet aggregation. Raw onions inhibit platelet aggregation; however, when onions are boiled or heated, antiplatelet activity may be abolished. Onion quarters were steamed for 0, 1, 3, 6, 10, and 15 min. The in vitro antiplatelet activity of a yellow hybrid storage onion was examined at these times on the blood of 12 human subjects using in vitro whole blood aggregometry. Contrary to findings reported for boiling, antiplatelet activity was destroyed between 3 and 6 min of steaming, and at 10 min of steaming, cooked onions stimulated platelet activity. Extracts from cooked onion had the potential to reverse the inhibitory effect on blood platelets by 25%. Responses were consistent across all donors. Total polyphenolic concentration and soluble solids were not affected by steaming time. The potential value of cooked onion preparations may result in destruction or reversal of antiplatelet activity, without affecting the polyphenolic concentration.

Platelet indices and glucose control in type 1 and type 2 diabetes mellitus: A case-control study.

PubMed

Zaccardi, F; Rocca, B; Rizzi, A; Ciminello, A; Teofili, L; Ghirlanda, G; De Stefano, V; Pitocco, D

2017-10-01

The relationship between platelet indices and glucose control may differ in type 1 (T1DM) and type 2 (T2DM) diabetes. We aimed to investigate differences in mean platelet volume (MPV), platelet count, and platelet mass between patients with T1DM, T2DM, and healthy controls and to explore associations between these platelet indices and glucose control. A total of 691 T1DM and 459 T2DM patients and 943 control subjects (blood donors) were included. HbA1c was measured in all subjects with diabetes and 36 T1DM patients further underwent 24 h-continuous glucose monitoring to estimate short-term glucose control (glucose mean and standard deviation). Adjusting for age and sex, platelet count was higher and MPV lower in both T1DM and T2DM patients vs control subjects, while platelet mass (MPV × platelet count) resulted higher only in T2DM. Upon further adjustment for HbA1c, differences in platelet count and mass were respectively 19.5 × 10 9 /L (95%CI: 9.8-29.3; p < 0.001) and 101 fL/nL (12-191; p = 0.027) comparing T2DM vs T1DM patients. MPV and platelet count were significantly and differently related in T2DM patients vs both T1DM and control subjects; this difference was maintained also accounting for HbA1c, age, and sex. Platelet mass and the volume-count relationship were significantly related to HbA1c only in T1DM patients. No associations were found between platelet indices and short-term glucose control. By accounting for confounders and glucose control, our data evidenced higher platelet mass and different volume-count kinetics in subjects with T2DM vs T1DM. Long-term glucose control seemed to influence platelet mass and the volume-count relationship only in T1DM subjects. These findings suggest different mechanisms behind platelet formation in T1DM and T2DM patients with long-term glycaemic control being more relevant in T1DM than T2DM. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Dual Therapy with Aspirin and Cilostazol May Improve Platelet Aggregation in Noncardioembolic Stroke Patients: A Pilot Study.

PubMed

Ohnuki, Yoichi; Ohnuki, Yuko; Kohara, Saori; Shimizu, Mie; Takizawa, Shunya

2017-01-01

Objective Some previous studies have found clinical benefit of dual antiplatelet therapy with aspirin and cilostazol for prevention of secondary stroke, but the physiological mechanism involved remains unknown. We aimed to clarify the effects of aspirin/cilostazol therapy on the platelet and endothelial functions of patients with acute noncardioembolic ischemic stroke, in comparison to patients who were treated with aspirin alone. Methods The present randomized prospective pilot study enrolled 24 patients within a week after the onset of noncardioembolic ischemic stroke. The patients were randomly allocated to receive aspirin (100 mg/day) (A group; 11 patients) or cilostazol (200 mg/day) plus aspirin (100 mg/day) (CA group; 13 patients). We measured platelet aggregation, platelet activation, and the thrombomodulin (TM), highly sensitive C-reactive protein (hs-CRP), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and von Willebrand (vWF) antigen levels and vWF activity over a 4-week period after enrollment. Results There was no significant difference in the platelet functions of the A and CA groups. However, the platelet aggregation induced by adenosine diphosphate (ADP) was decreased at 2 and 4 weeks (p<0.05) after treatment in comparison to the pre-treatment values in the CA group, but not in the A group. Platelet activation, and the hs-CRP, TM, ICAM-1, VCAM-1 and vWF values did not significantly decrease after treatment in either group. Conclusion Although there were no significant differences in platelet aggregation, platelet activation or the endothelial biomarker levels of the A and CA groups, dual therapy with aspirin and cilostazol inhibited platelet aggregation in comparison to the pre-treatment values, similarly to patients who received aspirin alone. This may suggest the clinical usefulness of dual therapy with aspirin and cilostazol in the treatment of patients with noncardioembolic ischemic stroke.

Hippophae rhamnoides L. Fruits Reduce the Oxidative Stress in Human Blood Platelets and Plasma.

PubMed

Olas, Beata; Kontek, Bogdan; Malinowska, Paulina; Żuchowski, Jerzy; Stochmal, Anna

2016-01-01

Effects of the phenolic fraction from Hippophae rhamnoides fruits on the production of thiobarbituric acid reactive substances (TBARS, a marker of lipid peroxidation) and the generation of superoxide anion (O2 (-∙)) in human blood platelets (resting platelets and platelets stimulated by a strong physiological agonist, thrombin) were studied in vitro. We also examined antioxidant properties of this fraction against human plasma lipid peroxidation and protein carbonylation induced by a strong biological oxidant, hydrogen peroxide (H2O2) or H2O2/Fe (a donor of hydroxyl radicals). The tested fraction of H. rhamnoides (0.5- 50 µg/mL; the incubation time: 15 and 60 min) inhibited lipid peroxidation induced by H2O2 or H2O2/Fe. The H. rhamnoides phenolic fraction inhibited not only plasma lipid peroxidation, but also plasma protein carbonylation stimulated by H2O2 or H2O2/Fe. Moreover, the level of O2 (-∙) in platelets significantly decreased. In comparative experiments, the H. rhamnoides fraction was a more effective antioxidant than aronia extract or grape seed extract (at the highest tested concentration, 50 µg/mL). The obtained results suggest that H. rhamnoides fruits may be a new, promising source of natural compounds with antioxidant and antiplatelet activity beneficial not only for healthy people, but also for those with oxidative stress-associated diseases.

Influence of chirality on catalytic generation of nitric oxide and platelet behavior on selenocystine immobilized TiO2 films.

PubMed

Fan, Yonghong; Pan, Xiaxin; Wang, Ke; Wu, Sisi; Han, Honghong; Yang, Ping; Luo, Rifang; Wang, Hong; Huang, Nan; Tan, Wei; Weng, Yajun

2016-09-01

As nitric oxide (NO) plays vital roles in the cardiovascular system, incorporating this molecule into cardiovascular stents is considered as an effective method. In the present study, selenocystine with different chirality (i.e., l- and d-selenocystine) was used as the catalytic molecule immobilized on TiO2 films for decomposing endogenous NO donor. The influences of surface chirality on NO release and platelet behavior were evaluated. Results show that although the amount of immobilized l-selenocystine on the surface was nearly the same as that of immobilized d-selenocystine, in vitro catalytic NO release tests showed that l-selenocystine immobilized surfaces were more capable of catalyzing the decomposition of S-nitrosoglutathione and thus generating more NO. Accordingly, l-selenocystine immobilized surfaces demonstrated significantly increased inhibiting effects on the platelet adhesion and activation, when compared to d-selenocystine immobilized ones. Measurement of the cGMP concentration of platelets further confirmed that surface chirality played an important role in regulating NO generation and platelet behaviors. Additionally, using bovine serum albumin and fibrinogen as model proteins, the protein adsorption determined with quartz crystal microbalance showed that the l-selenocystine immobilized surface enhanced protein adsorption. In conclusion, surface chirality significantly influences protein adsorption and NO release, which may have significant implications in the design of NO-generating cardiovascular stents. Copyright © 2016 Elsevier B.V. All rights reserved.

Platelet hyperaggregability in obesity: is there a role for nitric oxide impairment and oxidative stress?

PubMed

Leite, Natália Rodrigues Pereira; Siqueira de Medeiros, Mariana; Mury, Wanda Vianna; Matsuura, Cristiane; Perszel, Monique Bandeira Moss; Noronha Filho, Gerson; Brunini, Tatiana Mc; Mendes-Ribeiro, Antônio Claúdio

2016-08-01

Epidemiological evidence has shown that platelet activation markers are consistently elevated in obesity, contributing to its prothrombotic state. In order to improve the understanding of the regulation of platelet function in obesity, the aim of this study was to investigate the l-arginine-nitric oxide (NO) pathway in obese adults without other cardiovascular risk factor. Seventeen obese (body mass index [BMI] 35.9±1.0 kg/m(2) ) and eighteen age-matched normal weight subjects (BMI 22.0±0.6 kg/m(2) ) were included in this study. l-arginine influx was measured with incubation of l-[(3) H]-arginine. NO synthase (NOS) and arginase activities were determined by the citrulline assay and the conversion of l-[(14) C]-arginine to [(14) C]-urea, respectively. Cyclic guanosine monophosphate (cGMP) content was evaluated by enzyme-linked immunosorbent assay. In addition, the study analyzed: platelet aggregation; intraplatelet antioxidant enzymes, via superoxide dismutase (SOD) and catalase activities; and systemic levels of l-arginine, fibrinogen, and C-reactive protein (CRP). Obese patients presented a significant decrease of platelet l-arginine influx, NOS activity, and cGMP levels, along with platelet hyperaggregability. On the presence of NO donor, platelet aggregation was similar between the groups. The fibrinogen and CRP systemic levels were significantly higher and SOD activity was reduced in obesity. No significant differences were observed in plasma levels of l-arginine and intraplatelet arginase and catalase activities between groups. The diminished NO bioavailability associated with inflammatory status and impaired enzymatic antioxidant defence may contribute to future cardiovascular complications in obesity. © 2016 John Wiley & Sons Australia, Ltd.

Iron and cardiac ischemia: a natural, quasi-random experiment comparing eligible with disqualified blood donors.

PubMed

Germain, Marc; Delage, Gilles; Blais, Claudia; Maunsell, Elizabeth; Décary, Francine; Grégoire, Yves

2013-06-01

The theory that elevated iron stores can induce vascular injury and ischemia remains controversial. We conducted a cohort study of the effect of blood donation on the risk of coronary heart disease (CHD) by taking advantage of the quasi-random exclusion of donors who obtained a falsely reactive test for a transmissible disease (TD) marker. Whole blood donors who were permanently disqualified because of a false-reactive test between 1990 and 2007 in the province of Quebec were compared to donors who remained eligible, matched for baseline characteristics. The incidence of CHD after entry into the study was determined through hospitalization and death records. We compared eligible and disqualified donors using an "intention-to-treat" framework. Overall, 12,357 donors who were permanently disqualified were followed for 124,123 person-years of observation, plus 50,889 donors who remained eligible (516,823 person-years). On average, donors who remained eligible made 0.36 donation/year during follow-up and had an incidence of hospitalizations or deaths attributable to CHD of 3.60/1000 person-years, compared to 3.52 among permanently disqualified donors (rate ratio, 1.02; 95% confidence interval, 0.92-1.13). Donors who remained eligible did not have a lower risk of CHD, compared to donors who were permanently disqualified due to a false-reactive TD marker. Because of the quasi-random nature of false-reactive screening tests, this natural experiment has a level of validity approaching that of a randomized trial evaluating the effect of regular blood donation on CHD risk. These results do not support the iron hypothesis. © 2013 American Association of Blood Banks.

Comparison of deferral rates using a computerized versus written blood donor questionnaire: a randomized, cross-over study [ISRCTN84429599

PubMed Central

Sellors, John W; Hayward, Robert; Swanson, Graham; Ali, Anita; Haynes, R Brian; Bourque, Ronald; Moore, Karen-Ann; Lohfeld, Lynne; Dalby, Dawn; Howard, Michelle

2002-01-01

Background Self-administered computer-assisted blood donor screening strategies may elicit more accurate responses and improve the screening process. Methods Randomized crossover trial comparing responses to questions on a computerized hand-held tool (HealthQuiz, or HQ), to responses on the standard written instrument (Donor Health Assessment Questionnaire, or DHAQ). Randomly selected donors at 133 blood donation clinics in the area of Hamilton, Canada participated from 1995 to 1996. Donors were randomized to complete either the HQ or the DHAQ first, followed by the other instrument. In addition to responses of 'yes' and 'no' on both questionnaires, the HQ provided a response option of 'not sure'. The primary outcome was the number of additional donors deferred by the HQ. Results A total of 1239 donors participated. Seventy-one potential donors were deferred as a result of responses to the questionnaires; 56.3% (40/71) were deferred by the DHAQ, and an additional 43.7% (31/71) were deferred due to risks identified by the HQ but not by the DHAQ. Fourteen donors self-deferred; 11 indicated on the HQ that they should not donate blood on that day but did not use the confidential self-exclusion option on the DHAQ, and three used the self-exclusion option on the DHAQ but did not indicate that they should not donate blood on the HQ. The HQ identified a blood contact or risk factor for HIV/AIDS or sexually transmitted infection that was not identified by the DHAQ in 0.1% to 2.7% of donors. Conclusion A self-administered computerized questionnaire may increase risk reporting by blood donors. PMID:12191432

Efficacy of platelet-rich plasma applied to post-extraction retained lower third molar alveoli. A systematic review.

PubMed

Barona-Dorado, C; González-Regueiro, I; Martín-Ares, M; Arias-Irimia, O; Martínez-González, J-M

2014-03-01

Dental retentions have a high prevalence among the general population and their removal can involve multiple complications. The use of platelet rich plasma has been proposed in an attempt to avoid these complications, as it contains high growth factors and stimulates diverse biological functions that facilitate the healing of soft and hard tissues. To evaluate the available scientific evidence related to the application of platelet-rich plasma in the post-extraction alveoli of a retained lower third molars. A systematic review of published literature registered in the Medline, EMBASE, Cochrane and NIH databases. The following categories were included: human randomized clinical studies. Key search words were: platelet rich plasma; platelet rich plasma and oral surgery; platelet rich in growth factors and third molar. Of 101 potentially valid articles, seven were selected, of which four were rejected as they failed to meet quality criteria. Three studies fulfilled all selection and quality criteria: Ogundipe et al.; Rutkowski et al.; Haraji et al. The studies all measured osteoblast activity by means of sintigraphy, and also registered pain, bleeding, inflammation, temperature, numbness as perceived by the patients, radiological bone density and the incidence of alveolar osteitis. Scientific evidence for the use of PRP in retained third molar surgery is poor. For this reason randomized clinical trials are needed before recommendations for the clinical application of PRP can be made.

Onyalai--therapeutic effects of vincristine sulphate. A prospective randomized trial.

PubMed

Hesseling, P B; Girdle-Brown, B; Smit, J

1986-08-16

Twenty out of 40 patients with onyalai admitted to Rundu State Hospital, Kavango, SWA/Namibia, were randomized to receive a vincristine sulphate bolus of 1.5 mg/m2 or an equivalent volume of normal saline intravenously on days 8 and 15 when haemorrhage or a platelet count of less than 50 X 10(9)/l persisted for more than 1 week after admission. All patients were observed in hospital for at least 21 days. Five out of 10 patients who received vincristine achieved a platelet count in excess of 100 X 10(9)/l on day 21 and only 2 out of 10 patients who received placebo achieved a similar rise in the platelet count. Two patients, neither of whom was treated with vincristine, died of cerebral haemorrhage.

Consensus and update on the definition of on-treatment platelet reactivity to adenosine diphosphate associated with ischemia and bleeding.

PubMed

Tantry, Udaya S; Bonello, Laurent; Aradi, Daniel; Price, Matthew J; Jeong, Young-Hoon; Angiolillo, Dominick J; Stone, Gregg W; Curzen, Nick; Geisler, Tobias; Ten Berg, Jurrien; Kirtane, Ajay; Siller-Matula, Jolanta; Mahla, Elisabeth; Becker, Richard C; Bhatt, Deepak L; Waksman, Ron; Rao, Sunil V; Alexopoulos, Dimitrios; Marcucci, Rossella; Reny, Jean-Luc; Trenk, Dietmar; Sibbing, Dirk; Gurbel, Paul A

2013-12-17

Dual antiplatelet therapy with aspirin and a P2Y12 receptor blocker is a key strategy to reduce platelet reactivity and to prevent thrombotic events in patients treated with percutaneous coronary intervention. In an earlier consensus document, we proposed cutoff values for high on-treatment platelet reactivity to adenosine diphosphate (ADP) associated with post-percutaneous coronary intervention ischemic events for various platelet function tests (PFTs). Updated American and European practice guidelines have issued a Class IIb recommendation for PFT to facilitate the choice of P2Y12 receptor inhibitor in selected high-risk patients treated with percutaneous coronary intervention, although routine testing is not recommended (Class III). Accumulated data from large studies underscore the importance of high on-treatment platelet reactivity to ADP as a prognostic risk factor. Recent prospective randomized trials of PFT did not demonstrate clinical benefit, thus questioning whether treatment modification based on the results of current PFT platforms can actually influence outcomes. However, there are major limitations associated with these randomized trials. In addition, recent data suggest that low on-treatment platelet reactivity to ADP is associated with a higher risk of bleeding. Therefore, a therapeutic window concept has been proposed for P2Y12 inhibitor therapy. In this updated consensus document, we review the available evidence addressing the relation of platelet reactivity to thrombotic and bleeding events. In addition, we propose cutoff values for high and low on-treatment platelet reactivity to ADP that might be used in future investigations of personalized antiplatelet therapy. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Advances and controversies in neonatal ICU platelet transfusion practice.

PubMed

Christensen, Robert D

2008-01-01

Some of the platelet transfusions currently given to NICU patients are unnecessary and convey no benefits. Although ordered with good intentions, unnecessary platelet transfusions carry known and unknown risks. Identifying and eliminating any unnecessary platelet transfusions in NICUs would be a step toward better care, lower costs, and more careful preservation of blood component resources. A renewed interest in platelet transfusion studies is needed, if essential data is to be gathered to improve NICU platelet transfusion practice. Retrospective studies can be of value: for instance, seeking associations between bleeding events and platelet counts can suggest the possibility of cause and effect relationships. Such studies might identify approximate platelet count levels that convey high hemorrhagic risk and might help focus future prospective trials. Prospective indirect studies also can be of value, for instance, measuring the template bleeding time and the PFA-100 closure time as a function of platelet count and perhaps as a function of circulating platelet mass, and would provide new information with relevance to platelet transfusion benefits. Such studies might give a better awareness of how low the platelet count can fall before platelet plug formation is impaired. It seems inescapable, however, that new, multicentered, randomized, prospective studies are needed, where NICU patients are assigned different platelet transfusion triggers and then carefully tracked for bleeding events and long-term neurodevelopmental outcomes. Only that type of study is likely to generate the evidence base needed for widespread implementation of improvements in NICU platelet transfusion practice.

The persistence of hepatitis C virus transmission risk in China despite serologic screening of blood donations.

PubMed

Wang, Jingxing; Liu, Jing; Huang, Yi; Wright, David J; Li, Julin; Zhou, Zhongmin; He, Weilan; Yang, Tonghan; Yao, Fuzhu; Zhu, Xiangming; Wen, Guoxin; Bi, Xinhong; Tiemuer, Mei-hei-li; Wen, Xiuqiong; Huang, Mei; Cao, Ru'an; Yun, Zhongqiao; Lü, Yunlai; Ma, Hongli; Guo, Nan; Yu, Qilu; Ness, Paul; Shan, Hua

2013-10-01

A total of 2%-2.9% of the population in China is infected with hepatitis C virus (HCV). This study estimated the prevalence and incidence of HCV among Chinese blood donors. We examined whole blood and apheresis platelet donations at five Chinese blood centers in 2008 to 2010. All donations were screened using two rounds of testing for alanine aminotransferase, antibody to human immunodeficiency virus Types 1 and 2, hepatitis B surface antigen, anti-HCV, and syphilis. Screening reactivity is defined by a reactive result in one or both rounds of screening tests. Confirmatory tests (Ortho third-generation HCV enzyme immunoassay, Johnson & Johnson) were performed on anti-HCV screening-reactive samples. Confirmatory positive rates among first-time donors (prevalence) and repeat donors (incidence) were calculated by blood center and demographic categories. Donor characteristics associated with HCV confirmatory status among first-time donors were examined using trend test and multivariable logistic regression analysis. Among 821,314 donations, 40% came from repeat donors. The overall anti-HCV screening-reactive rate was 0.48%. Estimated HCV prevalence was 235 per 100,000 first-time donors; incidence was 10 per 100,000 person-years in repeat donors. In multivariable logistic regression analysis, first-time donors older than 25 years displayed higher HCV prevalence than the younger donors. Less education is associated with higher HCV prevalence. Donors 26 to 35 years old and those above 45 years displayed the highest incidence rate. High prevalence and incidence in donors indicate high residual risks for transfusion-transmitted HCV in Chinese patients. Implementation of minipool nucleic acid testing in routine donation screening may prevent a substantial number of transfusion-transmitted HCV infections. © 2013 American Association of Blood Banks.

Oleocanthal-rich extra virgin olive oil demonstrates acute anti-platelet effects in healthy men in a randomized trial

USDA-ARS?s Scientific Manuscript database

Objective: The cardiovascular benefit of extra virgin olive oils (EVOOs) may increase with their phenolic content or concentrations of specific phytochemicals. Oleocanthal and oleacin are EVOO phenolics, and as oleocanthal is a cyclooxygenase (COX) inhibitor, it may influence platelet aggregation. T...

Beneficial impacts of regular exercise on platelet function in sedentary older adults: Evidence from a randomized 6-month walking trial.

PubMed

Haynes, Andrew; Linden, Matthew D; Robey, Elisa; Naylor, Louise H; Ainslie, Philip N; Cox, Kay L; Lautenschlager, Nicola T; Green, Daniel J

2018-04-12

Platelet activation, including the formation of monocyte platelet aggregates (MPAs), contributes to atherosclerosis, thrombus formation and acute coronary syndromes. Regular participation in exercise can lower cardiovascular risk, but little is known regarding the impact of exercise training on platelet function. We investigated the effect of 6 months of walking exercise on platelet function in sedentary older adults without significant cardiovascular disease. Twenty-seven participants were randomly allocated to 6 months of either: no-exercise (n=13) or 3 x 50 mins/wk of supervised centre-based walking (n=14). Circulating and agonist induced MPAs were assessed using flow cytometry before (month 0 0M) and after (month 6 6M) the intervention. Circulating MPAs increased from 0M (3.7 {plus minus} 1.0%) to 6M (4.7 {plus minus} 1.6%) in the no-exercise group (P = 0.009), whereas a non-significant decrease was observed in the walking group (0M 4.3 {plus minus} 1.7% vs 6M 3.7 {plus minus} 1.2, P = 0.052). The change in MPAs between groups was significant (P = 0.001). There were no differences between groups in platelet responses to agonists across the interventions (all P > 0.05). Collectively, these data suggest that the absence of regular exercise may increase MPAs, which are cellular mediators involved in atherosclerosis, whilst regular walking inhibits such increases. The thrombotic function of platelets appear to be relatively unaltered by exercise training. This study provides novel data related to the cardio-protective effects associated with participation in exercise.

Comparative lipidomics and proteomics analysis of platelet lipid rafts using different detergents.

PubMed

Rabani, Vahideh; Davani, Siamak; Gambert-Nicot, Ségolène; Meneveau, Nicolas; Montange, Damien

2016-11-01

Lipid rafts play a pivotal role in physiological functions of platelets. Their isolation using nonionic mild detergents is considered as the gold standard method, but there is no consensual detergent for lipid raft studies. We aimed to investigate which detergent is the most suitable for lipid raft isolation from platelet membrane, based on lipidomics and proteomics analysis. Platelets were obtained from healthy donors. Twelve sucrose fractions were extracted by three different detergents, namely Brij 35, Lubrol WX, and Triton X100, at 0.05% and 1%. After lipidomics analysis and determination of fractions enriched in cholesterol (Ch) and sphingomyelin (SM), proteomics analysis was performed. Lipid rafts were mainly observed in 1-4 fractions, and non-rafts were distributed on 5-12 fractions. Considering the concentration of Ch and SM, Lubrol WX 1% and Triton X100 1% were more suitable detergents as they were able to isolate lipid raft fractions that were more enriched than non-raft fractions. By proteomics analysis, overall, 822 proteins were identified in platelet membrane. Lipid raft fractions isolated with Lubrol WX 0.05% and Triton X100 1% contained mainly plasma membrane proteins. However, only Lubrol WX 0.05 and 1% and Triton X100 1% were able to extract non-denaturing proteins with more than 10 transmembrane domains. Our results suggest that Triton X100 1% is the most suitable detergent for global lipid and protein studies on platelet plasma membrane. However, the detergent should be adapted if investigation of an association between specific proteins and lipid rafts is planned.

Hematopoietic stem cell transplantation from non-sibling matched family donors for patients with thalassemia major in Jordan.

PubMed

Hussein, Ayad Ahmed; Al-Zaben, Abdulhadi; Khattab, Eman; Haroun, Anas; Frangoul, Haydar

2016-02-01

There are limited data on the outcome of patients with thalassemia receiving HSCT from non-sibling matched family donors. Of the 341 patients with thalassemia major that underwent donor search at our center from January 2003 to December 2011, 236 (69.2%) had fully matched family donor of which 28 patients (8.2%) had non-sibling matched family donors identified. We report on seven patients with a median age of eight yr (4-21) who underwent myeloablative (n = 4) or RIC (n = 3) HSCT. The median age of the donors was 33 yr (4-47), three were parents, two first cousins, one paternal uncle, and one paternal aunt. All patients achieved primary neutrophil and platelet engraftment at a median of 18 (13-20) and 16 days (11-20), respectively. One patient developed grade II acute GVHD, and two patients developed limited chronic GVHD. One patient experienced secondary GF requiring a second transplant. At a median follow-up of 69 months (7-110), all patients are alive and thalassemia free. Our data emphasize the need for extended family HLA typing for patients with thalassemia major in regions where there is high rate of consanguinity. Transplant from non-sibling matched family donor can result in excellent outcome. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of garlic extract on platelet aggregation: a randomized placebo-controlled double-blind study.

PubMed

Morris, J; Burke, V; Mori, T A; Vandongen, R; Beilin, L J

1995-01-01

1. Studies of the effects of garlic on platelet aggregation have produced inconsistent results possibly related to variations in study design and in the garlic preparations used. 2. The present study examined the effects on platelet aggregation and serum thromboxane and lyso-platelet activating factor, of feeding garlic extract to healthy men using a placebo-controlled, double-blind design. The effects of the same garlic preparation on platelet aggregation in vitro were also investigated. 3. There were no significant differences in platelet aggregation with adenosine diphosphate, platelet activating factor (PAF) or collagen according to treatment group. Serum thromboxane and lysoPAF also showed no change related to garlic supplements. 4. In vitro aggregation with collagen decreased linearly with increasing amounts of garlic extract, but concentrations were higher than those attainable in vivo. Gastrointestinal side effects prevented the use of higher doses of garlic which must be considered to be pharmacological as they exceed changes achievable by dietary modification.

A pharmacodynamic comparison of prasugrel vs. high-dose clopidogrel in patients with type 2 diabetes mellitus and coronary artery disease: results of the Optimizing anti-Platelet Therapy In diabetes MellitUS (OPTIMUS)-3 Trial

PubMed Central

Angiolillo, Dominick J.; Badimon, Juan Jose; Saucedo, Jorge F.; Frelinger, Andrew L.; Michelson, Alan D.; Jakubowski, Joseph A.; Zhu, Baojin; Ojeh, Clement K.; Baker, Brian A.; Effron, Mark B.

2011-01-01

Aims Patients with diabetes mellitus (DM) have increased platelet reactivity and reduced platelet response to clopidogrel compared with patients without DM. Prasugrel, a more potent antiplatelet agent, is associated with greater reductions in ischaemic events compared with clopidogrel, particularly in patients with DM. The aim of this study was to perform serial pharmacodynamic assessments of prasugrel with high-dose clopidogrel in patients with DM. Methods and results Optimizing anti-Platelet Therapy In diabetes MellitUS (OPTIMUS)-3 was a prospective, randomized, double-blind, crossover study in patients with type 2 DM and coronary artery disease (CAD). Patients (n= 35) were randomly assigned to either prasugrel 60 mg loading dose (LD)/10 mg maintenance dose (MD) or clopidogrel 600 mg LD/150 mg MD over two 1-week treatment periods separated by a 2-week washout period. Platelet function was assessed by VerifyNow® P2Y12 assay, light transmission aggregometry, and vasodilator-stimulated phosphoprotein phosphorylation at 0, 1, 4, and 24 h and 7 days. Greater platelet inhibition by VerifyNow® P2Y12 was achieved by prasugrel compared with clopidogrel at 4 h post-LD (least squares mean, 89.3 vs. 27.7%, P< 0.0001; primary endpoint). The difference in platelet inhibition between prasugrel and clopidogrel was significant from 1 h through 7 days (P < 0.0001). Similar results were obtained using all other platelet function measures. Prasugrel resulted in fewer poor responders at all time points irrespective of definition used. Conclusion In patients with type 2 DM and CAD, standard-dose prasugrel is associated with greater platelet inhibition and better response profiles during both the loading and maintenance periods when compared with double-dose clopidogrel. Clinical trial identifier: www.clinicaltrials.gov—NCT00642174 PMID:21252171

Durability of small-for-size living donor allografts.

PubMed

Au, Kin Pan; Chan, See Ching; Chok, Kenneth Siu Ho; Chan, Albert Chi Yan; Wong, Tiffany Cho Lam; Sharr, William Wei; Lo, Chung Mau

2015-11-01

Our aim was to study the long-term outcomes of living donor liver transplantation using small-for-size (SFS) grafts. From July 2002 to July 2009, 233 patients received a right liver graft with a middle hepatic vein from a living donor in our center. Recipients were stratified according to the graft weight to recipient standard liver volume (GW/SLV) ratio into 4 groups: >50% (n = 89), >40% to 50% (n = 85), >35% to 40% (n = 38), and ≤ 35% (n = 21). They were compared in terms of graft survivals, biliary stricture rates, renal function in terms of estimated glomerular filtration rate (eGFR), platelet counts, and graft function in terms of serum bilirubin and international normalized ratio (INR). The 5-year graft survivals for patients with GW/SLV of >50%, >40% to 50%, >35% to 40% and ≤ 35% were 88.8%, 88.2%, 81.5%, and 81.0%, respectively. Transplantation for hepatocellular carcinoma affected graft survivals (P = 0.02), but graft size did not (P = 0.66). There were no differences in frequency of biliary stricture (21.3% versus 17.1% versus 21.1% versus 28.6%; P = 0.75). At each year after transplant, their platelet counts (P = 0.12-0.65), eGFR (P = 0.49-0.91), bilirubin (P = 0.14-0.51), and INR (P = 0.20-0.98) remained comparable. SFS grafts with GW/SLV ≤ 35% and >35% to 40% had comparable long-term outcomes with larger liver grafts. Graft size did not affect long-term graft survivals. © 2015 American Association for the Study of Liver Diseases.

Scalability and process transfer of mesenchymal stromal cell production from monolayer to microcarrier culture using human platelet lysate.

PubMed

Heathman, Thomas R J; Stolzing, Alexandra; Fabian, Claire; Rafiq, Qasim A; Coopman, Karen; Nienow, Alvin W; Kara, Bo; Hewitt, Christopher J

2016-04-01

The selection of medium and associated reagents for human mesenchymal stromal cell (hMSC) culture forms an integral part of manufacturing process development and must be suitable for multiple process scales and expansion technologies. In this work, we have expanded BM-hMSCs in fetal bovine serum (FBS)- and human platelet lysate (HPL)-containing media in both a monolayer and a suspension-based microcarrier process. The introduction of HPL into the monolayer process increased the BM-hMSC growth rate at the first experimental passage by 0.049 day and 0.127/day for the two BM-hMSC donors compared with the FBS-based monolayer process. This increase in growth rate in HPL-containing medium was associated with an increase in the inter-donor consistency, with an inter-donor range of 0.406 cumulative population doublings after 18 days compared with 2.013 in FBS-containing medium. Identity and quality characteristics of the BM-hMSCs are also comparable between conditions in terms of colony-forming potential, osteogenic potential and expression of key genes during monolayer and post-harvest from microcarrier expansion. BM-hMSCs cultured on microcarriers in HPL-containing medium demonstrated a reduction in the initial lag phase for both BM-hMSC donors and an increased BM-hMSC yield after 6 days of culture to 1.20 ± 0.17 × 10(5) and 1.02 ± 0.005 × 10(5) cells/mL compared with 0.79 ± 0.05 × 10(5) and 0.36 ± 0.04 × 10(5) cells/mL in FBS-containing medium. This study has demonstrated that HPL, compared with FBS-containing medium, delivers increased growth and comparability across two BM-hMSC donors between monolayer and microcarrier culture, which will have key implications for process transfer during scale-up. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Identification and Characterization of Anti-Platelet Antibodies in Idiopathic Thrombocytopenic Purpura Patients

PubMed Central

Aghabeigi, N; Lindsey, N; Zamani, A; Shishaeyan, B

2012-01-01

Background: The autoimmune disease known as Idiopathic (immune thrombocytopenic purpura thrombocytopenic purpura (ITP) is clinically defined by a low numbers of platelets in the circulation blood. This study aimed to isolate autoantibodies made against the platelet glycoproteins using platelets from healthy volunteers, to determine their specificity and further elucidate their effects on platelet function. Methods: This study used a phage display system to recognize Fab anti-platelet antibodies. Anti-platelet After isolation, the anti-platelet Fab-expressing phage was characterized by ELISA and Western blotting. The Fab-bearing phage pool obtained from five rounds of panning was analysed in order to determine its anti-platelet reactivity. Of the phage colonies obtained, 100 colonies of different sizes were randomly selected for reaction with whole platelets, using M13 phage as a negative control. Results: Twelve colonies of them had strong reactions against the whole platelet preparation, but only four colonies showed substantial reactivity against the lysed platelet preparation (lysate). Three of the four colonies showed three bands representing proteins with different molecular weights. The fourth colony showed only a single band. The final experiment to characterise the protein isolated from the phage library was a DNA gel agarose test. Conclusion: Each colony showed a DNA band that corresponded with the molecular size marker for 5.4 kbase pairs, and this suggested the presence of heavy and light antibody chains in the phage. PMID:23113135

Immunological complications of blood transfusions.

PubMed

Brand, Anneke

2016-01-01

Most adverse blood transfusion (BT) events are immune-mediated and in the majority of severe reactions antibodies can be identified as causal factors. Alloimmunization not only causes symptomatic reactions, transfused cells can also be (silently) destroyed. Immunization by BT can contribute to hemolytic disease of the newborn as well as to allograft rejection after transplantation. Reversely, pregnancy and transplantation may evoke immunity hampering transfusion therapy. Besides causing mortality and morbidity, alloimmunization has a huge economic impact. Transfusion reactions prolong hospital stay, require diagnostic tests and complex donor selection procedures and create the need for typed donor registries. In the 1970s, Opeltz and colleagues described that pre-transplantation BT impaired rejection of renal transplants. Leukocytes were essential for this immunosuppressive BT effect that raised concern about negative effects on cancer growth and resistance against infections. Studies on the mechanism were however preliminary abandoned when calcineurin inhibitors for prevention of graft rejection became available and since all blood products underwent leukoreduction in most countries as precautionary measure against transmission of variant Creutzfeldt-Jacob disease. Whether current leukoreduced BT are immunosuppressive and for which patients or circumstances this may contribute to worse outcome, is unknown. The last decades of the previous century, leukoreduction of cellular blood products for leukemia patients significantly reduced the incidence of immunological platelet transfusion refractoriness. The first decade of this century the avoidance of plasma- and platelet-products from females, that may contain donor-derived leukocyte antibodies, decreased transfusion related acute lung injury (TRALI) by more than 30%. These were major achievements. Challenge for the near future is to further reduce alloimmunization in particular against red blood cells (RBC) as a cause of severe hemolytic transfusion reactions and problems to find compatible donors. This can be achieved by extended matching. Inventory limitations prevent to match all BT for clinically relevant RBC antigens. A (European-wide) registration of clinical and genetic risk factors associated with alloimmunization could support effective use of matched blood products. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Blood donations from previously transfused or pregnant donors: a multicenter study to determine the frequency of alloexposure.

PubMed

Rios, Jorge A; Schlumpf, Karen S; Kakaiya, Ram M; Triulzi, Darrell J; Roback, John D; Kleinman, Steve H; Murphy, Edward L; Gottschall, Jerome L; Carey, Patricia M

2011-06-01

Transfusion-related acute lung injury (TRALI) mitigation strategies include the deferral of female donors from apheresis platelet (PLT) donations and the distribution of plasma for transfusion from male donors only. We studied the implications of these policies in terms of component loss at six blood centers in the United States. We collected data from allogeneic blood donors making whole blood and blood component donations during calendar years 2006 through 2008. We analyzed the distribution of donations in terms of the sex, transfusion and pregnancy histories, and blood type. A TRALI mitigation policy that would not allow plasma from female whole blood donors to be prepared into transfusable plasma components would result in nearly a 50% reduction in the units of whole blood available for plasma manufacturing and would decrease the number of type AB plasma units that could be made from whole blood donations by the same amount. Deferral of all female apheresis PLT donors, all female apheresis PLT donors with histories of prior pregnancies, or all female apheresis PLT donors with histories of prior pregnancies and positive screening test results for antibodies to human leukocyte antigens (HLAs) will result in a loss of 37.1, 22.5, and 5.4% of all apheresis PLT donations, respectively. A TRALI mitigation policy that only defers female apheresis PLT donors with previous pregnancies and HLAs would result in an approximately 5% decrease in the inventory of apheresis PLTs, but would eliminate a large proportion of components that are associated with TRALI. © 2010 American Association of Blood Banks.

A Randomized, Prospective, Parallel Group Study of Laparoscopic vs. Laparoendoscopic Single Site Donor Nephrectomy for Kidney Donation

PubMed Central

Aull, Meredith J.; Afaneh, Cheguevara; Charlton, Marian; Serur, David; Douglas, Melissa; Christos, Paul J.; Kapur, Sandip; Del Pizzo, Joseph J.

2014-01-01

Few prospective, randomized studies have assessed benefits of laparoendoscopic single site donor nephrectomy (LESS-DN) over laparoscopic donor nephrectomy (LDN). Our center initiated such a trial in January 2011, following subjects randomized to LESS-DN vs. LDN from surgery through 5 years post-donation. Subjects complete recovery/satisfaction questionnaires at 2, 6, and 12 months post-donation; transplant recipient outcomes are also recorded. 100 subjects (49 LESS-DN, 51 LDN) underwent surgery; donor demographics were similar between groups, and included a predominance of female, living unrelated donors, mean age of 47 years who underwent left donor nephrectomy. Operative parameters (overall time, time to extraction, warm ischemia time, blood loss) were similar between groups. Conversion to hand-assist laparoscopy was required in 3 LESS-DN (6.1%) vs. 2 LDN (3.9%; P=0.67). Questionnaires revealed 97.2% of LESS-DN vs. 79.5% of LDN (P=0.03) were 100% recovered by two months after donation. No significant difference was seen in satisfaction scores between the groups. Recipient outcomes were similar between groups. Our randomized trial comparing LESS donor nephrectomy to LDN confirms that LESS-DN offers a safe alternative to conventional LDN in terms of intra- and post-operative complications. LDN and LESS-DN offer similar recovery and satisfaction after donation. PMID:24934732

Platelet inhibitory effects of juices from Pachyrhizus erosus L. root and Psidium guajava L. fruit: a randomized controlled trial in healthy volunteers.

PubMed

Thaptimthong, Thitiporn; Kasemsuk, Thitima; Sibmooh, Nathawut; Unchern, Supeenun

2016-08-03

The purpose of this study is to investigate cardiovascular benefits of juices obtained from two commonly consumed fruits in Thailand, Pachyrhizus erosus, L. (yam bean) and Psidium guajava, L. (guava), by examining their acute cardiovascular effects in healthy volunteers. Possible involvements of the dietary nitrate on their effects were investigated as well. Thirty healthy volunteers were randomly divided into three groups of 10 subjects per group and each group was allocated to drink 500 ml of freshly prepared yam bean root juice, guava fruit juice, or water. Systemic nitrate and nitrite concentrations, heart rate, systolic and diastolic blood pressure, serum K(+) concentrations, ex vivo platelet aggregation, and plasma cGMP concentrations were monitored at the baseline and at various time points after the intake of juices or water. Data were compared by repeated measures ANOVA. Following the ingestion of both yam bean root juice and guava fruit juice, collagen-induced but not ADP-induced platelet aggregation was attenuated. Ingestion of yam bean root juice increased systemic nitrate and nitrite concentrations whereby elevated nitrite concentrations correlated with the extent of inhibiting collagen-induced platelet aggregation. In addition, positive correlation between systemic nitrite and plasma cGMP concentrations and negative correlation between plasma cGMP concentrations and the extent of collagen-induced platelet aggregation were revealed. Nevertheless, yam bean root juice reduced only diastolic blood pressure while guava fruit juice reduced heart rate, systolic and diastolic blood pressure. The present study has illustrated, for the first time, acute inhibitory effects of yam bean root juice and guava fruit juice on ex vivo collagen-induced platelet aggregation in healthy subjects. Dietary nitrate was shown to underlie the effect of yam bean root juice but not that of guava fruit juice. Following yam bean root juice ingestion, systemic nitrate apparently converts to nitrite and further to NO which may attenuate platelet responses to collagen stimulation. Cardiovascular benefits of juices from yam bean root and guava fruit are noteworthy in term of the cardiovascular health-promoting approach. Randomized controlled trial TCTR20150228001 .

A Multi-centric, Double-blind, Placebo-controlled, Randomized, Prospective Study to Evaluate the Efficacy and Safety of Carica papaya Leaf Extract, as Empirical Therapy for Thrombocytopenia associated with Dengue Fever.

PubMed

Kasture, Prabhu Nagnathappa; Nagabhushan, K H; Kumar, Arun

2016-06-01

Dengue is a rapidly expanding global health problem. Approximately 2.5 billion people live in dengue-risk regions with about 100 million new cases each year worldwide. The cumulative dengue diseases burden has attained an unprecedented proportion in recent times with sharp increase in the size of human population at risk. The management of dengue virus infection is essentially supportive and symptomatic and no specific treatment is available for increasing the fallen platelets, which have a significant role in causing the mortality of dengue patient.This study was conducted to evaluate the platelet increasing efficacy of Carica papaya leaf extract (CPLE) in patients with dengue fever (DF). The administration of Carica papaya leaf extract should significantly increase the platelet count in cases of thrombocytopenia associated with dengue, preventing the patient to go in DHF or DSS conditions. A Multi-centric, Double blind, Placebo controlled, Randomized, prospective study was conducted in 300 patients across 5 centres', to evaluate the Efficacy and Safety of Carica Papaya Leaf Extract, as empirical therapy for thrombocytopenia associated with dengue fever. The subjects were randomized into two groups, as control and intervention group. Both the groups were managed by the standard management guidelines for dengue except steroid administration. In addition to this, the intervention group received CPLE tablet three times daily for five days. All of them were followed daily with platelet monitoring. This study has been registered in the clinical trial registry-India (CTRI Registration number: CTRI/2015/05/005806). The results indicate that CPLE had significant increase(p< 0.01) in the platelet count over the therapy duration, in dengue fever patients, confirming CPLE accelerates the increase in platelet count compared to the control group. There were few adverse events related to GI disturbance like nausea and vomiting which were similar in both groups. Thus this study concluded that Carica papaya leaf extract (CPLE) does significantly increase the platelet count in patients with thrombocytopenia associated with dengue with fewer side effects and good tolerability.

Plateletpheresis efficiency and mathematical correction of software-derived platelet yield prediction: A linear regression and ROC modeling approach.

PubMed

Jaime-Pérez, José Carlos; Jiménez-Castillo, Raúl Alberto; Vázquez-Hernández, Karina Elizabeth; Salazar-Riojas, Rosario; Méndez-Ramírez, Nereida; Gómez-Almaguer, David

2017-10-01

Advances in automated cell separators have improved the efficiency of plateletpheresis and the possibility of obtaining double products (DP). We assessed cell processor accuracy of predicted platelet (PLT) yields with the goal of a better prediction of DP collections. This retrospective proof-of-concept study included 302 plateletpheresis procedures performed on a Trima Accel v6.0 at the apheresis unit of a hematology department. Donor variables, software predicted yield and actual PLT yield were statistically evaluated. Software prediction was optimized by linear regression analysis and its optimal cut-off to obtain a DP assessed by receiver operating characteristic curve (ROC) modeling. Three hundred and two plateletpheresis procedures were performed; in 271 (89.7%) occasions, donors were men and in 31 (10.3%) women. Pre-donation PLT count had the best direct correlation with actual PLT yield (r = 0.486. P < .001). Means of software machine-derived values differed significantly from actual PLT yield, 4.72 × 10 11 vs.6.12 × 10 11 , respectively, (P < .001). The following equation was developed to adjust these values: actual PLT yield= 0.221 + (1.254 × theoretical platelet yield). ROC curve model showed an optimal apheresis device software prediction cut-off of 4.65 × 10 11 to obtain a DP, with a sensitivity of 82.2%, specificity of 93.3%, and an area under the curve (AUC) of 0.909. Trima Accel v6.0 software consistently underestimated PLT yields. Simple correction derived from linear regression analysis accurately corrected this underestimation and ROC analysis identified a precise cut-off to reliably predict a DP. © 2016 Wiley Periodicals, Inc.

Comparison of Immature Platelet Count to Established Predictors of Platelet Reactivity During Thienopyridine Therapy.

PubMed

Stratz, Christian; Bömicke, Timo; Younas, Iris; Kittel, Anja; Amann, Michael; Valina, Christian M; Nührenberg, Thomas; Trenk, Dietmar; Neumann, Franz-Josef; Hochholzer, Willibald

2016-07-19

Previous data suggest that reticulated platelets significantly affect antiplatelet response to thienopyridines. It is unknown whether parameters describing reticulated platelets can predict antiplatelet response to thienopyridines. The authors sought to determine the extent to which parameters describing reticulated platelets can predict antiplatelet response to thienopyridine loading compared with established predictors. This study randomized 300 patients undergoing elective coronary stenting to loading with clopidogrel 600 mg, prasugrel 30 mg, or prasugrel 60 mg. Adenosine diphosphate (ADP)-induced platelet reactivity was assessed by impedance aggregometry before loading (intrinsic platelet reactivity) and again on day 1 after loading. Multiple parameters of reticulated platelets were assessed by automated whole blood flow cytometry: absolute immature platelet count (IPC), immature platelet fraction, and highly fluorescent immature platelet fraction. Each parameter of reticulated platelets correlated significantly with ADP-induced platelet reactivity (p < 0.01 for all 3 parameters). In a multivariable model including all 3 parameters, only IPC remained a significant predictor of platelet reactivity (p < 0.001). In models adjusting each of the 3 parameters for known predictors of on-treatment platelet reactivity including cytochrome P450 2C19 (CYP2C19) polymorphisms, age, body mass index, diabetes, and intrinsic platelet reactivity, only IPC prevailed as an independent predictor (p = 0.001). In this model, IPC was the strongest predictor of on-treatment platelet reactivity followed by intrinsic platelet reactivity. IPC is the strongest independent platelet count-derived predictor of antiplatelet response to thienopyridine treatment. Given its easy availability, together with its even stronger association with on-treatment platelet reactivity compared with known predictors, including the CYP2C19*2 polymorphism, IPC may become the preferred predictor of antiplatelet response to thienopyridine treatment. (Impact of Extent of Clopidogrel-Induced Platelet Inhibition During Elective Stent Implantation on Clinical Event Rate-Advanced Loading Strategies [ExcelsiorLOAD]; DRKS00006102). Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Pathogen-reduced platelets for the prevention of bleeding

PubMed Central

Estcourt, Lise J; Malouf, Reem; Hopewell, Sally; Trivella, Marialena; Doree, Carolyn; Stanworth, Simon J; Murphy, Michael F

2017-01-01

Background Platelet transfusions are used to prevent and treat bleeding in people who are thrombocytopenic. Despite improvements in donor screening and laboratory testing, a small risk of viral, bacterial, or protozoal contamination of platelets remains. There is also an ongoing risk from newly emerging blood transfusion-transmitted infections for which laboratory tests may not be available at the time of initial outbreak. One solution to reduce the risk of blood transfusion-transmitted infections from platelet transfusion is photochemical pathogen reduction, in which pathogens are either inactivated or significantly depleted in number, thereby reducing the chance of transmission. This process might offer additional benefits, including platelet shelf-life extension, and negate the requirement for gamma-irradiation of platelets. Although current pathogen-reduction technologies have been proven to reduce pathogen load in platelet concentrates, a number of published clinical studies have raised concerns about the effectiveness of pathogen-reduced platelets for post-transfusion platelet count recovery and the prevention of bleeding when compared with standard platelets. This is an update of a Cochrane review first published in 2013. Objectives To assess the effectiveness of pathogen-reduced platelets for the prevention of bleeding in people of any age requiring platelet transfusions. Search methods We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 9), MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 24 October 2016. Selection criteria We included RCTs comparing the transfusion of pathogen-reduced platelets with standard platelets, or comparing different types of pathogen-reduced platelets. Data collection and analysis We used the standard methodological procedures expected by Cochrane. Main results We identified five new trials in this update of the review. A total of 15 trials were eligible for inclusion in this review, 12 completed trials (2075 participants) and three ongoing trials. Ten of the 12 completed trials were included in the original review. We did not identify any RCTs comparing the transfusion of one type of pathogen-reduced platelets with another. Nine trials compared Intercept® pathogen-reduced platelets to standard platelets, two trials compared Mirasol® pathogen-reduced platelets to standard platelets; and one trial compared both pathogen-reduced platelets types to standard platelets. Three RCTs were randomised cross-over trials, and nine were parallel-group trials. Of the 2075 participants enrolled in the trials, 1981 participants received at least one platelet transfusion (1662 participants in Intercept® platelet trials and 319 in Mirasol® platelet trials). One trial included children requiring cardiac surgery (16 participants) or adults requiring a liver transplant (28 participants). All of the other participants were thrombocytopenic individuals who had a haematological or oncological diagnosis. Eight trials included only adults. Four of the included studies were at low risk of bias in every domain, while the remaining eight included studies had some threats to validity. Overall, the quality of the evidence was low to high across different outcomes according to GRADE methodology. We are very uncertain as to whether pathogen-reduced platelets increase the risk of any bleeding (World Health Organization (WHO) Grade 1 to 4) (5 trials, 1085 participants; fixed-effect risk ratio (RR) 1.09, 95% confidence interval (CI) 1.02 to 1.15; I2 = 59%, random-effect RR 1.14, 95% CI 0.93 to 1.38; I2 = 59%; low-quality evidence). There was no evidence of a difference between pathogen-reduced platelets and standard platelets in the incidence of clinically significant bleeding complications (WHO Grade 2 or higher) (5 trials, 1392 participants; RR 1.10, 95% CI 0.97 to 1.25; I2 = 0%; moderate-quality evidence), and there is probably no difference in the risk of developing severe bleeding (WHO Grade 3 or higher) (6 trials, 1495 participants; RR 1.24, 95% CI 0.76 to 2.02; I2 = 32%; moderate-quality evidence). There is probably no difference between pathogen-reduced platelets and standard platelets in the incidence of all-cause mortality at 4 to 12 weeks (6 trials, 1509 participants; RR 0.81, 95% CI 0.50 to 1.29; I2 = 26%; moderate-quality evidence). There is probably no difference between pathogen-reduced platelets and standard platelets in the incidence of serious adverse events (7 trials, 1340 participants; RR 1.09, 95% CI 0.88 to 1.35; I2 = 0%; moderate-quality evidence). However, no bacterial transfusion-transmitted infections occurred in the six trials that reported this outcome. Participants who received pathogen-reduced platelet transfusions had an increased risk of developing platelet refractoriness (7 trials, 1525 participants; RR 2.94, 95% CI 2.08 to 4.16; I2 = 0%; high-quality evidence), though the definition of platelet refractoriness differed between trials. Participants who received pathogen-reduced platelet transfusions required more platelet transfusions (6 trials, 1509 participants; mean difference (MD) 1.23, 95% CI 0.86 to 1.61; I2 = 27%; high-quality evidence), and there was probably a shorter time interval between transfusions (6 trials, 1489 participants; MD -0.42, 95% CI -0.53 to -0.32; I2 = 29%; moderate-quality evidence). Participants who received pathogen-reduced platelet transfusions had a lower 24-hour corrected-count increment (7 trials, 1681 participants; MD -3.02, 95% CI -3.57 to -2.48; I2 = 15%; high-quality evidence). None of the studies reported quality of life. We did not evaluate any economic outcomes. There was evidence of subgroup differences in multiple transfusion trials between the two pathogen-reduced platelet technologies assessed in this review (Intercept® and Mirasol®) for all-cause mortality and the interval between platelet transfusions (favouring Intercept®). Authors' conclusions Findings from this review were based on 12 trials, and of the 1981 participants who received a platelet transfusion only 44 did not have a haematological or oncological diagnosis. In people with haematological or oncological disorders who are thrombocytopenic due to their disease or its treatment, we found high-quality evidence that pathogen-reduced platelet transfusions increase the risk of platelet refractoriness and the platelet transfusion requirement. We found moderate-quality evidence that pathogen-reduced platelet transfusions do not affect all-cause mortality, the risk of clinically significant or severe bleeding, or the risk of a serious adverse event. There was insufficient evidence for people with other diagnoses. All three ongoing trials are in adults (planned recruitment 1375 participants) with a haematological or oncological diagnosis. PMID:28756627

Photochemical Inactivation of Chikungunya Virus in Human Apheresis Platelet Components by Amotosalen and UVA Light

PubMed Central

Tsetsarkin, Konstantin A.; Sampson-Johannes, Adam; Sawyer, Lynette; Kinsey, John; Higgs, Stephen; Vanlandingham, Dana L.

2013-01-01

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that recently re-emerged in Africa and rapidly spread into countries of the Indian Ocean basin and South-East Asia. The mean viremic blood donation risk for CHIKV on La Réunion reached 1.5% at the height of the 2005–2006 outbreaks, highlighting the need for development of safety measures to prevent transfusion-transmitted infections. We describe successful inactivation of CHIKV in human platelets and plasma using photochemical treatment with amotosalen and long wavelength UVA illumination. Platelet components in additive solution and plasma units were inoculated with two different strains of high titer CHIKV stock (6.0–8.0 logs/mL), and then treated with amotosalen and exposure to 1.0–3.0 J/cm2 UVA. Based on in vitro assays of infectious virus pre- and post-treatment to identify endpoint dilutions where virus was not detectable, mean viral titers could effectively be reduced by > 6.4 ± 0.6 log10 TCID50/mL in platelets and ≥ 7.6 ± 1.4 logs in plasma, indicating this treatment has the capacity to prevent CHIKV transmission in human blood components collected from infected donors in or traveling from areas of CHIKV transmission. PMID:23530077

Effectiveness of deep versus moderate muscle relaxation during laparoscopic donor nephrectomy in enhancing postoperative recovery: study protocol for a randomized controlled study.

PubMed

Bruintjes, Moira H D; Braat, Andries E; Dahan, Albert; Scheffer, Gert-Jan; Hilbrands, Luuk B; d'Ancona, Frank C H; Donders, Rogier A R T; van Laarhoven, Cornelis J H M; Warlé, Michiel C

2017-03-04

Postoperative recovery after live donor nephrectomy is largely determined by the consequences of postoperative pain and analgesia consumptions. The use of deep neuromuscular blockade has been shown to reduce postoperative pain scores after laparoscopic surgery. In this study, we will investigate whether deep neuromuscular blockade also improves the early quality of recovery after live donor nephrectomy. The RELAX-study is a phase IV, multicenter, double-blinded, randomized controlled trial, in which 96 patients, scheduled for living donor nephrectomy, will be randomized into two groups: one with deep and one with moderate neuromuscular blockade. Deep neuromuscular blockade is defined as a post-tetanic count of 1-2. Our primary outcome measurement will be the Quality of Recovery-40 questionnaire (overall score) at 24 h after extubation. This study is, to our knowledge, the first randomized study to assess the effectiveness of deep neuromuscular blockade during laparoscopic donor nephrectomy in enhancing postoperative recovery. The study findings may also be applicable for other laparoscopic procedures. clinicaltrials.gov, NCT02838134 . Registered on 29 June 2016.

Platelet-rich plasma and platelet gel preparation using Plateltex.

PubMed

Mazzucco, L; Balbo, V; Cattana, E; Borzini, P

2008-04-01

The platelet gel is made by embedding concentrate platelets within a semisolid (gel) network of polymerized fibrin. It is believed that this blood component will be used more and more in the treatment of several clinical conditions and as an adjunctive material in tissue engineering. Several systems are available to produce platelet-rich plasma (PRP) for topical therapy. Recently, a new system became commercially available, Plateltex. Here we report the technical performance of this system in comparison with the performance of other commercially available systems: PRGF, PRP-Landesber, Curasan, PCCS, Harvest, Vivostat, Regen and Fibrinet. Both the PRP and the gel were prepared according to the manufacturer's directions. The blood samples of 20 donors were used. The yield, the efficiency, and the amount of platelet-derived growth factor AB (PDGF-AB), transforming growth factor beta, vascular endothelial growth factor and fibroblast growth factor were measured in the resulting PRP. The feature of the batroxobin-induced gelation was evaluated. The yield, the collection efficiency and the growth factor content of Plateltex were comparable to those of most of the other available systems. The gelation time was not dependent on the fibrinogen concentration; however, it was strongly influenced by the contact surface area of the container where the clotting reaction took place (P < 0.0001). Plateltex provided platelet recovery, collection efficiency and PDGF-AB availability close to those provided by other systems marketed with the same intended use. Batroxobin, the enzyme provided to induce gelation, acts differently from thrombin, which is used by most other systems. Platelets treated with thrombin become activated; they release their growth factors quickly. Furthermore, thrombin-platelet interaction is a physiological mechanism that hastens the clot-retraction rate. On the contrary, platelets treated with batroxobin do not become activated; they are passively entrapped within the fibrin network, and their growth factor release occurs slowly. In these conditions, the clot retraction takes longer to occur. According to these differences between thrombin and batroxobin, it is expected that batroxobin-induced PRP activation will tailor slow release of the platelet content, thus, providing longer in loco availability of trophic factors. In selected clinical conditions, this durable anabolic factor availability might be preferable to quick thrombin-induced growth factor release.

Successful management of a hydropic fetus with severe anemia and thrombocytopenia caused by anti-CD36 antibody.

PubMed

Xu, Xiuzhang; Li, Lin; Xia, Wenjie; Ding, Haoqiang; Chen, Dawei; Liu, Jing; Deng, Jing; Chen, Yangkai; He, Zhiming; Wang, Jiali; Shao, Yuan; Santoso, Sentot; Ye, Xin; Fang, Qun

2018-02-01

Cases of CD36 deficiency are not rare in Asian populations, foetal and neonatal alloimmune thrombocytopenia (FNAIT) caused by anti-CD36 isoantibodies appears more frequent than other HPA alloantibodies. However, little is known about the treatment of anti-CD36 mediated FNAIT in this region. A Chinese male foetus, whose mother had a history of multiple intrauterine foetal demise and/or hydrops, was diagnosed with severe FNAIT at 27 weeks of gestational age. Immunological analysis revealed total absence of CD36 on platelets and monocytes from mother, caused by a 329-330delAC mutation of the CD36 gene. Anti-CD36 and anti-HLA class I antibodies were detected in the maternal serum, whereas only anti-CD36 isoantibodies were detectable in the foetal blood sample. Serial intrauterine transfusions with red blood cells (RBC) and platelets from a CD36null donor were performed to improve the severe anaemia and thrombocytopenia. The baby (2250 g; Apgar scores 10) was delivered vaginally at 32 weeks of gestation with normal haemoglobin (186 g/L) but low platelet count (48 × 10 9 /L). After 2 days the platelet count rose to 121 × 10 9 /L. This report suggests that intrauterine transfusions with compatible RBC and CD36null platelets are useful in preventing the deleterious clinical effects of anti-CD36-mediated severe FNAIT.

Hippophae rhamnoides L. Fruits Reduce the Oxidative Stress in Human Blood Platelets and Plasma

PubMed Central

Olas, Beata; Kontek, Bogdan; Malinowska, Paulina; Żuchowski, Jerzy; Stochmal, Anna

2016-01-01

Effects of the phenolic fraction from Hippophae rhamnoides fruits on the production of thiobarbituric acid reactive substances (TBARS, a marker of lipid peroxidation) and the generation of superoxide anion (O2 −∙) in human blood platelets (resting platelets and platelets stimulated by a strong physiological agonist, thrombin) were studied in vitro. We also examined antioxidant properties of this fraction against human plasma lipid peroxidation and protein carbonylation induced by a strong biological oxidant, hydrogen peroxide (H2O2) or H2O2/Fe (a donor of hydroxyl radicals). The tested fraction of H. rhamnoides (0.5– 50 µg/mL; the incubation time: 15 and 60 min) inhibited lipid peroxidation induced by H2O2 or H2O2/Fe. The H. rhamnoides phenolic fraction inhibited not only plasma lipid peroxidation, but also plasma protein carbonylation stimulated by H2O2 or H2O2/Fe. Moreover, the level of O2 −∙ in platelets significantly decreased. In comparative experiments, the H. rhamnoides fraction was a more effective antioxidant than aronia extract or grape seed extract (at the highest tested concentration, 50 µg/mL). The obtained results suggest that H. rhamnoides fruits may be a new, promising source of natural compounds with antioxidant and antiplatelet activity beneficial not only for healthy people, but also for those with oxidative stress-associated diseases. PMID:26933473

Protocolized fluid therapy in brain-dead donors: The multi-center randomized MOnIToR trial

PubMed Central

Al-Khafaji, Ali; Elder, Michele; Lebovitz, Daniel J; Murugan, Raghavan; Souter, Michael; Stuart, Susan; Wahed, Abdus S.; Keebler, Ben; Dils, Dorrie; Mitchell, Stephanie; Shutterly, Kurt; Wilkerson, Dawn; Pearse, Rupert; Kellum, John A

2015-01-01

BACKGROUND Critical shortages of organs for transplantation jeopardize many lives. Observational data suggest that better fluid management for deceased organ donors could increase organ recovery. We conducted the first large multi-center randomized trial in brain-dead donors to determine whether protocolized fluid therapy increases organs transplanted. METHODS We randomly assigned donors to either protocolized or usual care in eight organ procurement organizations. A “protocol-guided fluid therapy” algorithm targeting cardiac index, mean arterial pressure and pulse pressure variation was used. Our primary outcome was the number of organs transplanted per donor and our primary analysis was intention-to-treat. Secondary analyses included: 1) modified intention-to-treat where only subjects able to receive the intervention were included, and 2) twelve-month survival in transplant recipients. The study was stopped early. RESULTS We enrolled 556 donors; 279 protocolized care, 277 usual care. Groups had similar characteristics at baseline. The study protocol could be implemented in 76% of subjects randomized to the intervention. There was no significant difference in mean number of organs transplanted per donor: 3.39 organs per donor, (95%CI: 3.14-3.63) with protocolized care, compared to usual care 3.29 (95%CI: 3.04-3.54) (mean difference, 0.1, 95%CI: -0.25 to 0.45; p=0.56). In modified intention-to-treat analysis the mean number of organs increased (3.52 organs per donor, 95%CI: 3.23-3.8) but was not statistically significant (mean difference, 0.23, 95%CI: -0.15-0.61; p=0.23). Among the 1430 recipients of organs from study subjects, with data available, 56 deaths (7.8%) occurred in the protocolized care arm and 56 (7.9%) in the usual care arm in the first year (Hazard Ratio: 0.97, p=0.86). CONCLUSIONS In brain-dead organ donors, protocol-guided fluid therapy compared to usual care may not increase the number of organs transplanted per donor. PMID:25583616

Inhibition of platelet function by low-dose plain and micro-encapsulated acetylsalicylic acid.

PubMed

Waldemar, G; Petersen, P; Boysen, G; Knudsen, J B

1988-04-15

The effect of two acetylsalicylic acid (ASA) formulations, plain (Magnyl) and micro-encapsulated (Globentyl), on platelet aggregation, thromboxane formation, and bleeding time was studied in 12 healthy volunteers in a randomized double-blind cross-over study. All subjects were treated with Magnyl and Globentyl (75 mg daily) in periods of 2 weeks, separated by a wash-out period of 2 weeks. Both drugs significantly depressed platelet aggregation and thromboxane formation and prolonged bleeding time without difference in mode of action of the drugs. It is concluded that significant inhibition of platelet activity may be achieved by low-dose ASA treatment with micro-encapsulated as well as with plain formulations.

Comparison of the effect of aspirin and choline magnesium trisalicylate on thromboxane biosynthesis in human platelets: role of the acetyl moiety.

PubMed

Danesh, B J; McLaren, M; Russell, R I; Lowe, G D; Forbes, C D

1989-01-01

Parameters of platelet thromboxane biosynthesis were measured 24 h after ingestion of equivalent salicylate doses (500 mg) of aspirin (ASA) and choline magnesium trisalicylate (CMT), a non-acetylated salicylate. In random order, 10 healthy volunteers received these drugs on 2 separate days, 2 weeks apart. While ASA significantly prolonged bleeding time, and decreased plasma thromboxane generation and serum thromboxane B2 levels, CMT failed to produce such effects. Thus CMT, which lacks an acetyl moiety in its structure, has no inhibitory effect on platelet thromboxane biosynthesis, and may therefore be considered safer than ASA for therapeutic use, when inhibition of platelet function can be hazardous.

Comparison of the therapeutic effects of ultrasound-guided platelet-rich plasma injection and dry needling in rotator cuff disease: a randomized controlled trial.

PubMed

Rha, Dong-wook; Park, Gi-Young; Kim, Yong-Kyun; Kim, Min Tae; Lee, Sang Chul

2013-02-01

To compare the effects of platelet-rich plasma injection with those of dry needling on shoulder pain and function in patients with rotator cuff disease. A single-centre, prospective, randomized, double-blinded, controlled study. University rehabilitation hospital. Thirty-nine patients with a supraspinatus tendon lesion (tendinosis or a partial tear less than 1.0 cm, but not a complete tear) who met the inclusion criteria recruited between June 2010 and February 2011. Two dry needling procedures in the control group and two platelet-rich plasma injections in the experimental group were applied to the affected shoulder at four-week intervals using ultrasound guidance. The Shoulder Pain and Disability Index, passive range of motion of the shoulder, a physician global rating scale at the six-month follow-up, adverse effects monitoring and an ultrasound measurement were used as outcome measures. The clinical effect of the platelet-rich plasma injection was superior to the dry needling from six weeks to six months after initial injection (P < 0.05). At six months the mean Shoulder Pain and Disability Index was 17.7 ± 3.7 in the platelet-rich plasma group versus 29.5 ± 3.8 in the dry needling group (P < 0.05). No severe adverse effects were observed in either group. Autologous platelet-rich plasma injections lead to a progressive reduction in the pain and disability when compared to dry needling. This benefit is certainly still present at six months after treatment. These findings suggest that treatment with platelet-rich plasma injections is safe and useful for rotator cuff disease.

Differential effects of hormone therapy on serotonin, vascular function and mood in the KEEPS.

PubMed

Raz, L; Hunter, L V; Dowling, N M; Wharton, W; Gleason, C E; Jayachandran, M; Anderson, L; Asthana, S; Miller, V M

2016-01-01

Serotonin (5-hydroxytryptamine, 5-HT) is modulated by sex steroid hormones and affects vascular function and mood. In the Kronos Early Estrogen Prevention Cognitive and Affective Ancillary Study (KEEPS-Cog), women randomized to oral conjugated equine estrogens (oCEE) showed greater benefit on affective mood states than women randomized to transdermal 17β-estradiol (tE2) or placebo (PL). This study examined the effect of these treatments on the platelet content of 5-HT as a surrogate measure of 5-HT synthesis and uptake in the brain. The following were measured in a subset (n = 79) of women enrolled in KEEPS-Cog: 5-HT by ELISA, carotid intima-medial thickness (CIMT) by ultrasound, endothelial function by reactive hyperemic index (RHI), and self-reported symptoms of affective mood states by the Profile of Mood States (POMS) questionnaire. Mean platelet content of 5-HT increased by 107.0%, 84.5% and 39.8%, in tE2, oCEE and PL groups, respectively. Platelet 5-HT positively correlated with estrone in the oCEE group and with 17β- estradiol in the tE2 group. Platelet 5-HT showed a positive association with RHI, but not CIMT, in the PL and oCEE groups. Reduction in mood scores for depression-dejection and anger-hostility was associated with elevations in platelet 5-HT only in the oCEE group (r = -0.5, p = 0.02). Effects of oCEE compared to tE2 on RHI and mood may be related to mechanisms involving platelet, and perhaps neuronal, uptake and release of 5-HT and reflect conversion of estrone to bioavailable 17β-estradiol in platelets and the brain.

A randomized trial of blood donor recruitment strategies.

PubMed

Reich, Pascale; Roberts, Paula; Laabs, Nancy; Chinn, Artina; McEvoy, Patrick; Hirschler, Nora; Murphy, Edward L

2006-07-01

Improvement in donor return rates, especially among first-time donors, may significantly improve the blood supply. There are few rigorous studies of the effectiveness of various approaches to donor recruitment, however. By use of a single-blind, randomized trial design, 6919 post-September 11, 2001, first-time donors were randomly assigned into the following intervention arms: T-shirt incentive versus none, recruitment scripts with a patient story (Script A) versus a complimentary message including the donor's blood type (Script B), and telephone versus e-mail recruitment. Our primary outcome was a second donation within 6 months. Rate ratios (RRs) and 95 percent confidence intervals (95% CIs) were calculated with Taylor series methods. A total of 1421 (20.5%) first-time donors returned within the 6 months, including 1252 with a second and 169 with both second and third donations. The T-shirt incentive was not effective in increasing returns compared to no incentive (20.5% vs. 20.6%; RR, 0.99; 95% CI, 0.91-1.09). Script A was significantly more effective than Script B (22.2% vs. 18.9%; RR, 1.18; 95% CI, 1.07-1.29). E-mail was substantially less effective than telephone recruitment (13.2% vs. 27.8%; RR, 0.48; 95% CI, 0.40-0.57). A T-shirt incentive had no apparent effect, but an empathetic message significantly improved the return donation rate. E-mail recruitment was substantially less effective than telephone recruitment, perhaps due to technical problems. The study illustrates the utility of the randomized clinical trial study design for testing donor recruitment strategies.

Long-range ordering effect in electrodeposition of zinc and zinc oxide.

PubMed

Liu, Tao; Wang, Sheng; Shi, Zi-Liang; Ma, Guo-Bin; Wang, Mu; Peng, Ru-Wen; Hao, Xi-Ping; Ming, Nai-Ben

2007-05-01

In this paper, we report the long-range ordering effect observed in the electro-crystallization of Zn and ZnO from an ultrathin aqueous electrolyte layer of ZnSO4 . The deposition branches are regularly angled, covered with random-looking, scalelike crystalline platelets of ZnO. Although the orientation of each crystalline platelet of ZnO appears random, transmission electron microscopy shows that they essentially possess the same crystallographic orientation as the single-crystalline zinc electrodeposit underneath. Based on the experimental observations, we suggest that this unique long-range ordering effect results from an epitaxial nucleation effect in electrocrystallization.

The antiplatelet effect of higher loading and maintenance dose regimens of clopidogrel: the PRINC (Plavix Response in Coronary Intervention) trial.

PubMed

Gladding, Patrick; Webster, Mark; Zeng, Irene; Farrell, Helen; Stewart, Jim; Ruygrok, Peter; Ormiston, John; El-Jack, Seif; Armstrong, Guy; Kay, Patrick; Scott, Douglas; Gunes, Arzu; Dahl, Marja-Liisa

2008-12-01

This study evaluated the antiplatelet effect of a higher loading and maintenance dose regimen of clopidogrel and a possible drug interaction with verapamil. Clopidogrel loading doses above 600 mg have not resulted in more rapid or complete platelet inhibition. Higher maintenance dosages may be more effective than 75 mg/day. A double-blind, randomized, placebo-controlled trial was undertaken in 60 patients undergoing percutaneous coronary intervention. All patients received clopidogrel 600 mg at the start of the procedure. Using a 2 x 2 design, patients were allocated to clopidogrel 600 mg given 2 h later or matching placebo, and to verapamil 5 mg intra-arterial or placebo. Platelet function was measured using the VerifyNow P2Y12 analyzer (Accumetrics Ltd., San Diego, California) at 2, 4, and 7 h. Patients were further randomized to receive a clopidogrel 75 or 150 mg once daily, with platelet function assessed after 1 week. Two hours after the second dose of clopidogrel or placebo, platelet inhibition was 42 +/- 27% with clopidogrel, compared with 24 +/- 22% with placebo (p = 0.0006). By 5 h after the second dose, platelet inhibition was 49 +/- 30% with clopidogrel, compared with 29 +/- 22% with placebo (p = 0.01). No drug interaction was seen with verapamil. A clopidogrel maintenance dosage of 150 mg daily for 1 week resulted in greater platelet inhibition than 75 mg daily (50 +/- 28% vs. 29 +/- 19%, p = 0.01). In an unselected population undergoing percutaneous coronary intervention a clopidogrel 1,200-mg loading dose, given as two 600-mg doses 2 h apart, results in more rapid and complete platelet inhibition than a single 600-mg dose. A maintenance dosage of 150 mg daily produces greater platelet inhibition than 75 mg daily. (The PRINC trial; ACTRN12606000129583).

A randomized, double-blind, placebo- controlled study on the anti-haemostatic effects of Curcuma longa, Angelica sinensis and Panax ginseng.

PubMed

Fung, Foon Yin; Wong, Wan Hui; Ang, Seng Kok; Koh, Hwee Ling; Kun, Mei Ching; Lee, Lai Heng; Li, Xiaomei; Ng, Heng Joo; Tan, Chuen Wen; Zhao, Yan; Linn, Yeh Ching

2017-08-15

Herbs with "blood-activating" properties by traditional medicine theory often raise concerns for their possible anti-platelet or anticoagulation effects based on reports from in vitro studies. Such herbs have been implicated for bleeding manifestations based on only anecdotal reports. In particular, the combination of such herbs with anti-platelet agents is often empirically advised against despite lack of good clinical evidence. Here we studied 3 commonly used herbal preparations Curcuma longa, Angelica sinensis and Panax ginseng on their respective anti-platelet and anticoagulation effect, alone and in combination with aspirin. This is a randomized, double-blind, placebo-controlled trial involving 25 healthy volunteers for each herbal preparation. Each subject underwent 3 phases comprising of herbal product alone, aspirin alone and aspirin with herbal product, where each phase lasted for 3 weeks with 2 weeks of washout between phases. PT/APTT, platelet function by light transmission aggregometry and thrombin generation assay by calibrated automated thrombogram were measured at baseline and after each phase. Information on adverse reaction including bleeding manifestations was collected after each phase. On the whole there was no clinically relevant impact on platelet and coagulation function. With the exception of 5 of 24 subjects in the Curcuma longa group, 2 of 24 subjects in the Angelica sinensis group and 1 of 23 subjects in the Panax ginseng group who had an inhibition in arachidonic-acid induced platelet aggregation, there was no effect of these 3 herbals products on platelet aggregation by other agonists. Combination of these herbal products with aspirin respectively did not further aggravate platelet inhibition caused by aspirin. None of the herbs impaired PT/APTT or thrombin generation. There was no significant bleeding manifestation. This study on healthy volunteers provides good evidence on the lack of bleeding risks of Curcuma longa, Angelica sinensis and Panax ginseng either used alone or in combination with aspirin. Copyright © 2017 Elsevier GmbH. All rights reserved.

Human platelet antigen (HPA)-1a peptides do not reliably suppress anti-HPA-1a responses using a humanized severe combined immunodeficiency (SCID) mouse model

PubMed Central

Jackson, D J; Eastlake, J L; Kumpel, B M

2014-01-01

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) occurs most frequently when human platelet antigen (HPA)-1a-positive fetal platelets are destroyed by maternal HPA-1a immunoglobulin (Ig)G antibodies. Pregnancies at risk are treated by administration of high-dose intravenous Ig (IVIG) to women, but this is expensive and often not well tolerated. Peptide immunotherapy may be effective for ameliorating some allergic and autoimmune diseases. The HPA-1a/1b polymorphism is Leu/Pro33 on β3 integrin (CD61), and the anti-HPA-1a response is restricted to HPA-1b1b and HLA-DRB3*0101-positive pregnant women with an HPA-1a-positive fetus. We investigated whether or not HPA-1a antigen-specific peptides that formed the T cell epitope could reduce IgG anti-HPA-1a responses, using a mouse model we had developed previously. Peripheral blood mononuclear cells (PBMC) in blood donations from HPA-1a-immunized women were injected intraperitoneally (i.p.) into severe combined immunodeficient (SCID) mice with peptides and HPA-1a-positive platelets. Human anti-HPA-1a in murine plasma was quantitated at intervals up to 15 weeks. HPA-1a-specific T cells in PBMC were identified by proliferation assays. Using PBMC of three donors who had little T cell reactivity to HPA-1a peptides in vitro, stimulation of anti-HPA-1a responses by these peptides occurred in vivo. However, with a second donation from one of these women which, uniquely, had high HPA-1a-specific T cell proliferation in vitro, marked suppression of the anti-HPA-1a response by HPA-1a peptides occurred in vivo. HPA-1a peptide immunotherapy in this model depended upon reactivation of HPA-1a T cell responses in the donor. For FNAIT, we suggest that administration of antigen-specific peptides to pregnant women might cause either enhancement or reduction of pathogenic antibodies. PMID:24261689

Induction of Scleroderma Fibrosis in Skin-Humanized Mice by Administration of Anti-Platelet-Derived Growth Factor Receptor Agonistic Autoantibodies.

PubMed

Luchetti, Michele M; Moroncini, Gianluca; Jose Escamez, Maria; Svegliati Baroni, Silvia; Spadoni, Tatiana; Grieco, Antonella; Paolini, Chiara; Funaro, Ada; Avvedimento, Enrico V; Larcher, Fernando; Del Rio, Marcela; Gabrielli, Armando

2016-09-01

To describe a skin-SCID mouse chimeric model of systemic sclerosis (SSc; scleroderma) fibrosis based on engraftment of ex vivo-bioengineered skin using skin cells derived either from scleroderma patients or from healthy donors. Three-dimensional bioengineered skin containing human keratinocytes and fibroblasts isolated from skin biopsy specimens from healthy donors or SSc patients was generated ex vivo and then grafted onto the backs of SCID mice. The features of the skin grafts were analyzed by immunohistochemistry, and the functional profile of the graft fibroblasts was defined before and after treatment with IgG from healthy controls or SSc patients. Two procedures were used to investigate the involvement of platelet-derived growth factor receptor (PDGFR): 1) nilotinib, a tyrosine kinase inhibitor, was administered to mice before injection of IgG from SSc patient sera (SSc IgG) into the grafts, and 2) human anti-PDGFR monoclonal antibodies were injected into the grafts. Depending on the type of bioengineered skin grafted, the regenerated human skin exhibited either the typical scleroderma phenotype or the healthy human skin architecture. Treatment of animals carrying healthy donor skin grafts with SSc IgG resulted in the appearance of a bona fide scleroderma phenotype, as confirmed by increased collagen deposition and fibroblast activation markers. Results of the experiments involving administration of nilotinib or monoclonal antibodies confirmed the involvement of PDGFR. Our results provide the first in vivo demonstration of the fibrotic properties of anti-PDGFR agonistic antibodies. This bioengineered skin-humanized mouse model can be used to test in vivo the progression of the disease and to monitor response to antifibrotic drugs. © 2016, American College of Rheumatology.

Clinical management and outcomes of patients with Hermansky-Pudlak syndrome pulmonary fibrosis evaluated for lung transplantation

PubMed Central

El-Chemaly, Souheil; O’Brien, Kevin J.; Nathan, Steven D.; Weinhouse, Gerald L.; Goldberg, Hilary J.; Connors, Jean M.; Cui, Ye; Astor, Todd L.; Camp, Philip C.; Rosas, Ivan O.; Lemma, Merte; Speransky, Vladislav; Merideth, Melissa A.; Gahl, William A.

2018-01-01

Pulmonary fibrosis is a progressive, fatal manifestation of Hermansky-Pudlak syndrome (HPS). Some patients with advanced HPS pulmonary fibrosis undergo lung transplantation despite their disease-associated bleeding tendency; others die while awaiting donor organs. The objective of this study is to determine the clinical management and outcomes of a cohort with advanced HPS pulmonary fibrosis who were evaluated for lung transplantation. Six patients with HPS-1 pulmonary fibrosis were evaluated at the National Institutes of Health Clinical Center and one of two regional lung transplant centers. Their median age was 41.5 years pre-transplant. Three of six patients died without receiving a lung transplant. One of these was referred with end-stage pulmonary fibrosis and died before a donor organ became available, and donor organs were not identified for two other patients sensitized from prior blood product transfusions. Three of six patients received bilateral lung transplants; they did not have a history of excessive bleeding. One patient received peri-operative desmopressin, one was transfused with intra-operative platelets, and one received extracorporeal membrane oxygenation and intra-operative prothrombin complex concentrate, platelet transfusion, and desmopressin. One transplant recipient experienced acute rejection that responded to pulsed steroids. No evidence of chronic lung allograft dysfunction or recurrence of HPS pulmonary fibrosis was detected up to 6 years post-transplant in these three lung transplant recipients. In conclusion, lung transplantation and extracorporeal membrane oxygenation are viable options for patients with HPS pulmonary fibrosis. Alloimmunization in HPS patients is an important and potentially preventable barrier to lung transplantation; interventions to limit alloimmunization should be implemented in HPS patients at risk of pulmonary fibrosis to optimize their candidacy for future lung transplants. PMID:29547626

Clinical management and outcomes of patients with Hermansky-Pudlak syndrome pulmonary fibrosis evaluated for lung transplantation.

PubMed

El-Chemaly, Souheil; O'Brien, Kevin J; Nathan, Steven D; Weinhouse, Gerald L; Goldberg, Hilary J; Connors, Jean M; Cui, Ye; Astor, Todd L; Camp, Philip C; Rosas, Ivan O; Lemma, Merte; Speransky, Vladislav; Merideth, Melissa A; Gahl, William A; Gochuico, Bernadette R

2018-01-01

Pulmonary fibrosis is a progressive, fatal manifestation of Hermansky-Pudlak syndrome (HPS). Some patients with advanced HPS pulmonary fibrosis undergo lung transplantation despite their disease-associated bleeding tendency; others die while awaiting donor organs. The objective of this study is to determine the clinical management and outcomes of a cohort with advanced HPS pulmonary fibrosis who were evaluated for lung transplantation. Six patients with HPS-1 pulmonary fibrosis were evaluated at the National Institutes of Health Clinical Center and one of two regional lung transplant centers. Their median age was 41.5 years pre-transplant. Three of six patients died without receiving a lung transplant. One of these was referred with end-stage pulmonary fibrosis and died before a donor organ became available, and donor organs were not identified for two other patients sensitized from prior blood product transfusions. Three of six patients received bilateral lung transplants; they did not have a history of excessive bleeding. One patient received peri-operative desmopressin, one was transfused with intra-operative platelets, and one received extracorporeal membrane oxygenation and intra-operative prothrombin complex concentrate, platelet transfusion, and desmopressin. One transplant recipient experienced acute rejection that responded to pulsed steroids. No evidence of chronic lung allograft dysfunction or recurrence of HPS pulmonary fibrosis was detected up to 6 years post-transplant in these three lung transplant recipients. In conclusion, lung transplantation and extracorporeal membrane oxygenation are viable options for patients with HPS pulmonary fibrosis. Alloimmunization in HPS patients is an important and potentially preventable barrier to lung transplantation; interventions to limit alloimmunization should be implemented in HPS patients at risk of pulmonary fibrosis to optimize their candidacy for future lung transplants.

Motivational Differences between Whole Blood and Apheresis Donors in Quebec, Canada: A Questionnaire-Based Survey in a Voluntary Nonremunerated Context.

PubMed

Charbonneau, Johanne; Cloutier, Marie-Soleil; Carrier, Élianne

2015-01-01

Background. Finding ways to recruit apheresis donors is crucial. The aim of this study was to provide a quantitative analysis of the motivations of regular plasma/platelets donors (PPDs) in comparison with those of regular whole blood donors (WBDs), in a voluntary and nonremunerated context. Study Design and Methods. Motives to donate blood and demographic characteristics were collected through questionnaires completed by 795 WBDs and 473 PPDs. Chi-square tests were completed to determine which motivations stand out across the two blood donor groups. Results. The motivator selected by the highest percentage was "my blood can save lives." Comparison of WBDs and PPDs showed that 12 out of 23 items were statistically significantly different from one group to another. Conclusion. The belief that helping others is in their nature is more prevalent among PPDs. In this sense, their profile is unique. Four other motivators distinguish this group from the WBDs: "I think there is a strong need for blood products," "it gives me a sense of pride," "I like to have goals," and "I receive telephone reminders." These motivators point to the role the ongoing support provided by blood collection agencies (BCAs) plays with PPDs.

Motivational Differences between Whole Blood and Apheresis Donors in Quebec, Canada: A Questionnaire-Based Survey in a Voluntary Nonremunerated Context

PubMed Central

Charbonneau, Johanne; Cloutier, Marie-Soleil; Carrier, Élianne

2015-01-01

Background. Finding ways to recruit apheresis donors is crucial. The aim of this study was to provide a quantitative analysis of the motivations of regular plasma/platelets donors (PPDs) in comparison with those of regular whole blood donors (WBDs), in a voluntary and nonremunerated context. Study Design and Methods. Motives to donate blood and demographic characteristics were collected through questionnaires completed by 795 WBDs and 473 PPDs. Chi-square tests were completed to determine which motivations stand out across the two blood donor groups. Results. The motivator selected by the highest percentage was “my blood can save lives.” Comparison of WBDs and PPDs showed that 12 out of 23 items were statistically significantly different from one group to another. Conclusion. The belief that helping others is in their nature is more prevalent among PPDs. In this sense, their profile is unique. Four other motivators distinguish this group from the WBDs: “I think there is a strong need for blood products,” “it gives me a sense of pride,” “I like to have goals,” and “I receive telephone reminders.” These motivators point to the role the ongoing support provided by blood collection agencies (BCAs) plays with PPDs. PMID:26295006

Platelet-mediated transformation of mtDNA-less human cells: Analysis of phenotypic variability among clones from normal individuals-and complementation behavior of the tRNA[sup Lys] mutation causing myoclonic epilepsy and ragged red fibers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chomyn, A.; Lai, S.T.; Shakeley, R.

1994-06-01

In the present work, the authors demonstrate the possibility of using human blood platelets as mitochondrial donors for the repopulation of mtDNA-less ([rho][sup o]) cells. The noninvasive nature of platelet isolation, combined with the prolonged viability of platelet mitochondria and the simplicity and efficiency of the mitochondria-transfer procedure, has substantially increased the applicability of the [rho][sup o] cell transformation approach for mitochondrial genetic analysis and for the study of mtDNA-linked diseases. This approach has been applied to platelets from several normal human individuals and one individual affected by the myoclonic-epilepsy-and-ragged-red-fibers (MERRF) encephalomyopathy. A certain variability in respiratory capacity was observedmore » among the platelet-derived [rho][sup o] cell transformants from a given normal subject, and it was shown to be unrelated to their mtDNA content. The results of sequential transfer of mitochondria from selected transformants into a [rho][sup o] cell line different from the first [rho][sup o] acceptor strongly suggest that this variability reflected, at least in part, differences in nuclear gene content and/or activity among the original recipient cells. A much greater variability in respiratory capacity was observed among the transformants derived from the MERRF patient and was found to be related to the presence and amount of the mitochondrial tRNA[sup Lys] mutation associated with the MERRF syndrome. An analysis of the relationship between proportion of mtDNA carrying the MERRF mutation and degree of respiratory activity in various transformations derived from the MERRF patient revealed an unusual complementation behavior of the tRNA[sup Lys] mutation, possibly reflecting the distribution of mutant mtDNA among the platelet mitochondria. 29 refs., 4 figs., 1 tab.« less

Early impact of prescription Omega-3 fatty acids on platelet biomarkers in patients with coronary artery disease and hypertriglyceridemia.

PubMed

Serebruany, Victor L; Miller, Michael; Pokov, Alex N; Lynch, Donald; Jensen, Jesper K; Hallén, Jonas; Atar, Dan

2011-01-01

Prescription omega-3-acid ethyl esters (PO-3A) have been tested for outcome benefits in patients with coronary artery disease (CAD), arrhythmias and heart failure. Some evidence suggests that PO-3A may exert their benefit via inhibiting platelets. We tested the hypothesis that PO-3A may inhibit platelet activity in patients with documented stable CAD, beyond the antiplatelet properties of aspirin and statins. Thirty patients with documented CAD and triglycerides over 250 mg/dl treated with aspirin (70-160 mg/daily) and statins (simvastatin equivalence dose: 5-40 mg/daily) were randomized 1:1:1 to Omacor™ 1 g/day (DHA/EPA ratio 1.25:1.0), Omacor 2 g/day, or a placebo for 2 weeks. Platelet tests including aggregometry and flow cytometry and cartridge analyzer readings were performed at baseline and at 1 and 2 weeks following PO-3A therapy. ADP-induced platelet aggregation (p = 0.037), GP IIb/IIIa antigen (p = 0.031) and activity (p = 0.024), and P-selectin (p = 0.041) were significantly reduced after PO-3A, while platelet/endothelial cell adhesion molecule (p = 0.09), vitronectin receptor (p = 0.16), formation of platelet-monocyte microparticles (p = 0.19) and the VerifyNow IIb/IIIa test (p = 0.27) only exhibited nonsignificant trends suggestive of reduced platelet activity. Finally, collagen- and arachidonic acid-induced aggregation, closure time with the PFA-100 device and expression of thrombospondin (CD36), GP Ib (CD42b), LAMP-3 (CD63), LAMP-1 (CD107a), CD40-ligand (CD154), GP37 (CD165), and PAR-1 receptor intact (SPAN 12) and cleaved (WEDE-15) epitopes were not affected by 2 weeks of PO-3A. Independently of the dose and already at 1 week, short-term therapy with PO-3A provided a modest reduction of platelet activity biomarkers, despite concomitant aspirin and statin therapy, when compared to a placebo. The effect of PO-3A is unique, differs from other known antiplatelet agents and suggests potential pleiotropism. These preliminary randomized data call for confirmation in prospective studies. Copyright © 2011 S. Karger AG, Basel.

Genetic polymorphisms of human platelet antigens in Euro-African and Japanese descendants from Parana, Southern Brazil.

PubMed

Silvestre, Ana Paula Avenia; Zacarias, Joana Maira Valentini; Guelsin, Gláucia Andréia Soares; Visentainer, Jeane Eliete Laguila; Sell, Ana Maria

2017-09-01

The frequency distributions of HPA-1 to HPA-6 and HPA-15 were evaluated in two Brazilian populations from Parana: a mixed population of predominantly Caucasians and a population of Japanese descendants. Genotyping was performed by PCR-SSP in 364 unrelated individuals. Differences in the distribution of HPA highlight diversity in Brazilian miscegenation and the importance of formation of the HPA panel composed of regional blood donors.

A randomized controlled trial oftransfusion-related acute lung injury: is plasma from multiparous blood donors dangerous?

PubMed

Palfi, M; Berg, S; Ernerudh, J; Berlin, G

2001-03-01

Transfusion-related acute lung injury (TRALI) and other posttransfusion reactions may be caused by granulocyte and/or HLA antibodies, which are often present in blood from multiparous donors. The purpose of this study was to compare the effects of plasma from multiparous donors with those of plasma from donors with no history of transfusion or pregnancy (control plasma) in a prospective, randomized, double-blind, crossover study. Intensive care patients, judged to need at least 2 units of plasma, were randomly assigned to receive a unit of control plasma and, 4 hours later, a plasma unit from a multiparous donor (> or = 3 live births) or to receive the plasma units in opposite order. The patients were closely monitored, and body temperature, blood pressure, and heart rate were recorded. Blood samples for analysis of blood gases, TNFalpha, IL-1 receptor antagonist, soluble E selectin, and C3d complement factor were collected at least on four occasions (before and after the transfusion of each unit). Transfusion of plasma from multiparous donors was associated with significantly lower oxygen saturation and higher TNFalpha concentrations than transfusion of control plasma. The mean arterial pressure increased significantly after the transfusion of control plasma, whereas plasma from multiparous donors had no effect on it. Five posttransfusion reactions were observed in 100 patients, in four cases after the transfusion of plasma from multiparous donors. Plasma from multiparous blood donors may impair pulmonary function in intensive care unit patients.

The state of the science of whole blood: lessons learned at Mayo Clinic.

PubMed

Stubbs, James R; Zielinski, Martin D; Jenkins, Donald

2016-04-01

AABB Standards specify that ABO group-specific whole blood is the only acceptable choice for whole blood transfusions. Although universal donor group O stored whole blood (SWB) was used extensively by the military during the wars of the mid-twentieth century, its use has fallen out of favor and has never been used to great extent in the civilian trauma population. Interest in the use of whole blood has been renewed, particularly in light of its potential value in far-forward military and other austere environments. Evidence of preserved platelet function in SWB has heightened enthusiasm for a "one stop shop" resuscitation product providing volume, oxygen carrying capacity, and hemostatic effects. Experience with universal donor group O SWB is required to ascertain whether its use will be an advance in trauma care. Described here is the process of establishing a universal donor group O SWB at a civilian trauma center in the United States. © 2016 AABB.

Water administration and the risk of syncope and pre-syncope during blood donation: a randomized clinical trial

PubMed Central

van den Berg, Karin; Lam, Jameson; Bruhn, Roberta; Custer, Brian; Murphy, Edward L

2012-01-01

Background Blood centers rely heavily upon adolescent donors to meet blood demand, but pre-syncope and syncope are more frequent in younger donors. Studies have suggested administration of water prior to donation may reduce syncope and/or pre-syncope in this group. Study design and methods We conducted a randomized, controlled trial to establish the effect of pre-loading with 500ml of water on the rate of syncope and pre-syncope in adolescent donors. School collection sites in Eastern Cape Province of South Africa were randomized to receive water or not. Incidence of syncope and pre-syncope was compared between randomization groups using multivariable logistic regression. Results Of 2,464 study participants, 1,337 received water and 1,127 did not; groups differed slightly by gender and race. Syncope or pre-syncope was seen in 23 (1.7%) of the treatment and 18 (1.6%) of the control arm subjects. After adjusting for race, gender, age and donation history, there was no difference in outcome between the water versus no water arms (adjusted odds ratio (OR) = 0.80 (95% CI 0.42–1.53). Black donors had 7-fold lower odds of syncope or pre-syncope than their white counterparts (adjusted OR 0.14, 95% CI 0.04–0.47). Conclusion Preloading adolescent donors with 500ml of water did not have a major effect in reducing syncope and pre-syncope in South African adolescent donors. Our adolescent donors had a lower overall syncope and pre-syncope rate than similar populations in the USA, limiting the statistical power of the study. We confirmed much lower rates of syncope and pre-syncope among young Black donors. PMID:22486209

Osteoblastic mesenchymal stem cell sheet combined with Choukroun platelet-rich fibrin induces bone formation at an ectopic site.

PubMed

Wang, Zhifa; Weng, Yanming; Lu, Shengjun; Zong, Chunlin; Qiu, Jianyong; Liu, Yanpu; Liu, Bin

2015-08-01

To analyze the effects of platelet-rich fibrin (PRF) on mesenchymal stem cells (MSCs) in vitro and investigate in vivo bone formation by MSC sheets with PRF. Cell proliferation and expression of osteogenesis-related genes within MSC sheets were assessed upon exposure to PRF from the same donors. We then injected MSC sheet fragments with or without PRF subcutaneously in nude mice and assessed bone formation by micro-computed tomography and histological analyses. PRF significantly stimulated MSC proliferation and osteogenesis in vitro. MSC sheets injected with or without PRF formed new bone, but those with PRF produced significantly more and denser bone. MSC sheets can be used to generate tissue engineered bone upon injection, and PRF increases the osteogenic capacity of MSC sheets in vitro and in vivo. © 2014 Wiley Periodicals, Inc.

[Innovative technology and blood safety].

PubMed

Begue, S; Morel, P; Djoudi, R

2016-11-01

If technological innovations are not enough alone to improve blood safety, their contributions for several decades in blood transfusion are major. The improvement of blood donation (new apheresis devices, RFID) or blood components (additive solutions, pathogen reduction technology, automated processing of platelets concentrates) or manufacturing process of these products (by automated processing of whole blood), all these steps where technological innovations were implemented, lead us to better traceability, more efficient processes, quality improvement of blood products and therefore increased blood safety for blood donors and patients. If we are on the threshold of a great change with the progress of pathogen reduction technology (for whole blood and red blood cells), we hope to see production of ex vivo red blood cells or platelets who are real and who open new conceptual paths on blood safety. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Modification of Pulsed Electric Field Conditions Results in Distinct Activation Profiles of Platelet-Rich Plasma.

PubMed

Frelinger, Andrew L; Gerrits, Anja J; Garner, Allen L; Torres, Andrew S; Caiafa, Antonio; Morton, Christine A; Berny-Lang, Michelle A; Carmichael, Sabrina L; Neculaes, V Bogdan; Michelson, Alan D

2016-01-01

Activated autologous platelet-rich plasma (PRP) used in therapeutic wound healing applications is poorly characterized and standardized. Using pulsed electric fields (PEF) to activate platelets may reduce variability and eliminate complications associated with the use of bovine thrombin. We previously reported that exposing PRP to sub-microsecond duration, high electric field (SMHEF) pulses generates a greater number of platelet-derived microparticles, increased expression of prothrombotic platelet surfaces, and differential release of growth factors compared to thrombin. Moreover, the platelet releasate produced by SMHEF pulses induced greater cell proliferation than plasma. To determine whether sub-microsecond duration, low electric field (SMLEF) bipolar pulses results in differential activation of PRP compared to SMHEF, with respect to profiles of activation markers, growth factor release, and cell proliferation capacity. PRP activation by SMLEF bipolar pulses was compared to SMHEF pulses and bovine thrombin. PRP was prepared using the Harvest SmartPreP2 System from acid citrate dextrose anticoagulated healthy donor blood. PEF activation by either SMHEF or SMLEF pulses was performed using a standard electroporation cuvette preloaded with CaCl2 and a prototype instrument designed to take into account the electrical properties of PRP. Flow cytometry was used to assess platelet surface P-selectin expression, and annexin V binding. Platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), endothelial growth factor (EGF) and platelet factor 4 (PF4), and were measured by ELISA. The ability of supernatants to stimulate proliferation of human epithelial cells in culture was also evaluated. Controls included vehicle-treated, unactivated PRP and PRP with 10 mM CaCl2 activated with 1 U/mL bovine thrombin. PRP activated with SMLEF bipolar pulses or thrombin had similar light scatter profiles, consistent with the presence of platelet-derived microparticles, platelets, and platelet aggregates whereas SMHEF pulses primarily resulted in platelet-derived microparticles. Microparticles and platelets in PRP activated with SMLEF bipolar pulses had significantly lower annexin V-positivity than those following SMHEF activation. In contrast, the % P-selectin positivity and surface P-selectin expression (MFI) for platelets and microparticles in SMLEF bipolar pulse activated PRP was significantly higher than that in SMHEF-activated PRP, but not significantly different from that produced by thrombin activation. Higher levels of EGF were observed following either SMLEF bipolar pulses or SMHEF pulses of PRP than after bovine thrombin activation while VEGF, PDGF, and PF4 levels were similar with all three activating conditions. Cell proliferation was significantly increased by releasates of both SMLEF bipolar pulse and SMHEF pulse activated PRP compared to plasma alone. PEF activation of PRP at bipolar low vs. monopolar high field strength results in differential platelet-derived microparticle production and activation of platelet surface procoagulant markers while inducing similar release of growth factors and similar capacity to induce cell proliferation. Stimulation of PRP with SMLEF bipolar pulses is gentler than SMHEF pulses, resulting in less platelet microparticle generation but with overall activation levels similar to that obtained with thrombin. These results suggest that PEF provides the means to alter, in a controlled fashion, PRP properties thereby enabling evaluation of their effects on wound healing and clinical outcomes.

Positive effect of an autologous platelet concentrate in lateral epicondylitis in a double-blind randomized controlled trial: platelet-rich plasma versus corticosteroid injection with a 1-year follow-up.

PubMed

Peerbooms, Joost C; Sluimer, Jordi; Bruijn, Daniël J; Gosens, Taco

2010-02-01

Platelet-rich plasma (PRP) has shown to be a general stimulation for repair. Purpose To determine the effectiveness of PRP compared with corticosteroid injections in patients with chronic lateral epicondylitis. Randomized controlled trial; Level of evidence, 1. The trial was conducted in 2 teaching hospitals in the Netherlands. One hundred patients with chronic lateral epicondylitis were randomly assigned in the PRP group (n = 51) or the corticosteroid group (n = 49). A central computer system carried out randomization and allocation to the trial group. Patients were randomized to receive either a corticosteroid injection or an autologous platelet concentrate injection through a peppering technique. The primary analysis included visual analog scores and DASH Outcome Measure scores (DASH: Disabilities of the Arm, Shoulder, and Hand). Successful treatment was defined as more than a 25% reduction in visual analog score or DASH score without a reintervention after 1 year. The results showed that, according to the visual analog scores, 24 of the 49 patients (49%) in the corticosteroid group and 37 of the 51 patients (73%) in the PRP group were successful, which was significantly different (P <.001). Furthermore, according to the DASH scores, 25 of the 49 patients (51%) in the corticosteroid group and 37 of the 51 patients (73%) in the PRP group were successful, which was also significantly different (P = .005). The corticosteroid group was better initially and then declined, whereas the PRP group progressively improved. Treatment of patients with chronic lateral epicondylitis with PRP reduces pain and significantly increases function, exceeding the effect of corticosteroid injection. Future decisions for application of the PRP for lateral epicondylitis should be confirmed by further follow-up from this trial and should take into account possible costs and harms as well as benefits.

Protocolized fluid therapy in brain-dead donors: the multicenter randomized MOnIToR trial.

PubMed

Al-Khafaji, Ali; Elder, Michele; Lebovitz, Daniel J; Murugan, Raghavan; Souter, Michael; Stuart, Susan; Wahed, Abdus S; Keebler, Ben; Dils, Dorrie; Mitchell, Stephanie; Shutterly, Kurt; Wilkerson, Dawn; Pearse, Rupert; Kellum, John A

2015-03-01

Critical shortages of organs for transplantation jeopardize many lives. Observational data suggest that better fluid management for deceased organ donors could increase organ recovery. We conducted the first large multicenter randomized trial in brain-dead donors to determine whether protocolized fluid therapy increases the number of organs transplanted. We randomly assigned donors to either protocolized or usual care in eight organ procurement organizations. A "protocol-guided fluid therapy" algorithm targeting the cardiac index, mean arterial pressure and pulse pressure variation was used. Our primary outcome was the number of organs transplanted per donor, and our primary analysis was intention to treat. Secondary analyses included: (1) modified intention to treat where only subjects able to receive the intervention were included and (2) 12-month survival in transplant recipients. The study was stopped early. We enrolled 556 donors: 279 protocolized care and 277 usual care. Groups had similar characteristics at baseline. The study protocol could be implemented in 76 % of subjects randomized to the intervention. There was no significant difference in mean number of organs transplanted per donor: 3.39 organs per donor (95 % CI 3.14-3.63) with protocolized care compared to 3.29 usual care (95 % CI 3.04-3.54; mean difference, 0.1, 95 % CI -0.25 to 0.45; p = 0.56). In modified intention-to-treat analysis the mean number of organs increased (3.52 organs per donor, 95 % CI 3.23-3.8), but not statistically significantly (mean difference, 0.23, 95 % CI -0.15 to 0.61; p = 0.23). Among the 1,430 recipients of organs from study subjects with data available, 56 deaths (7.8 %) occurred in the protocolized care arm and 56 (7.9 %) in the usual care arm in the first year (hazard ratio: 0.97, p = 0.86). In brain-dead organ donors, protocol-guided fluid therapy compared to usual care may not increase the number of organs transplanted per donor.

Umbilical Cord Blood Platelet Lysate as Serum Substitute in Expansion of Human Mesenchymal Stem Cells.

PubMed

Shirzad, Negin; Bordbar, Sima; Goodarzi, Alireza; Mohammad, Monire; Khosravani, Pardis; Sayahpour, Froughazam; Baghaban Eslaminejad, Mohamadreza; Ebrahimi, Marzieh

2017-10-01

The diverse clinical applications for human mesenchymal stem cells (hMSCs) in cellular therapy and regenerative medicine warrant increased focus on developing adequate culture supplements devoid of animal-derived products. In the present study, we have investigated the feasibility of umbilical cord blood-platelet lysate (UCB-PL) as a standard substitute for fetal bovine serum (FBS) and human peripheral blood-PL (PB-PL). In this experimental study, platelet concentrates (PC) from UCB and human PB donors were frozen, melted, and sterilized to obtain PL. Quality control included platelet cell counts, sterility testing (viral and microbial), total protein concentrations, growth factor levels, and PL stability. The effects of UCB-PL and PB-PL on hMSCs proliferation and differentiation into osteocytes, chondrocytes, and adipocytes were studied and the results compared with FBS. UCB-PL contained high levels of protein content, platelet-derived growth factor- AB (PDGF-AB), and transforming growth factor (TGF) compared to PB-PL. All growth factors were stable for at least nine months post-storage at -70˚C. hMSCs proliferation enhanced following treatment with UCB-PL. With all three supplements, hMSCs could differentiate into all three lineages. PB-PL and UCB-PL both were potent in hMSCs proliferation. However, PB promoted osteoblastic differentiation and UCB-PL induced chondrogenic differentiation. Because of availability, ease of use and feasible standardization of UCB-PL, we have suggested that UCB-PL be used as an alternative to FBS and PB-PL for the cultivation and expansion of hMSCs in cellular therapy. Copyright© by Royan Institute. All rights reserved.

Deviation from the Forster theory for time-dependent donor decays for randomly distributed molecules in solution

NASA Astrophysics Data System (ADS)

Lakowicz, Joseph R.; Szmacinski, Henryk; Johnson, Michael L.

1990-05-01

We examined the time -dependent donor decays of 2 - amino purine (2 -APU) , in the presence of increasing amounts of acceptor 2-aminobenzophenine (2-ABP). As the concentration of 2-ABP increases, the frequency-responses diverge from that predicted by Forster. The data were found to be consistent with modified Forster equations, but at this time we do not state that these modified expressions provide a correct molecular description of this donor-acceptor system. To the best of our knowledge this is the first paper which reports a failure of the Forster theory for randomly distributed donors and acceptors.

Pathogen reduction of blood components.

PubMed

Solheim, Bjarte G

2008-08-01

Thanks to many blood safety interventions introduced in developed countries the risk of transfusion transmitted infections has become exceedingly small in these countries. However, emerging pathogens still represent a serious challenge, as demonstrated by West Nile virus in the US and more recently by Chikungunya virus in the Indian Ocean. In addition bacterial contamination, particularly in platelets, and protozoa transmitted by blood components still represent sizeable risks in developed countries. In developing countries the risk of all transfusion transmitted infections is still high due to insufficient funding and organisation of the health service. Pathogen reduction of pooled plasma products has virtually eliminated the risk of transfusion transmitted infections, without compromising the quality of the products significantly. Pathogen reduction of blood components has been much more challenging. Solvent detergent treatment which has been so successfully applied for plasma products dissolves cell membranes, and can, therefore, only be applied for plasma and not for cellular blood components. Targeting of nucleic acids has been another method for pathogen inactivation of plasma and the only approach possible for cellular blood products. As documented in more than 15 year's track record, solvent detergent treatment of pooled plasma can yield high quality plasma. The increased risk for contamination by unknown viruses due to pooling is out weighed by elimination of TRALI, significant reduction in allergic reactions and standardisation of the product. Recently, a promising method for solvent detergent treatment of single donor plasma units has been published. Methylene blue light treatment of single donor plasma units has a similar long track record as pooled solvent detergent treated plasma; but the method is less well documented and affects coagulation factor activity more. Psoralen light treated plasma has only recently been introduced (CE marked in Europe, but not licensed by the FDA), while the method of Riboflavin light treatment of plasma still is under development. In addition to pathogen reduction the methods, however, result in some reduction of coagulation factor activity. For platelets only Psoralen and Riboflavin light treatment have been implemented. Both are CE marked products in Europe but only approved for clinical trials in the USA. The methods affect platelet activity, but result in clinically acceptable platelets with only slightly reduced CCI and increased demand for platelet transfusions. Pathogen reduction of red blood cells with FRALE (S-303) or INACTINE (PEN110) has so far resulted in the formation of antibodies against neo-epitopes on red blood cells. A promising method for Riboflavin treatment of red blood cells is under development. This manuscript reviews the current experience and discusses future trends.

Platelet growth factors from allogeneic platelet-rich plasma for clinical improvement in split-thickness skin graft.

PubMed

Sonker, Atul; Dubey, Anju; Bhatnagar, Ankur; Chaudhary, Rajendra

2015-01-01

Platelets are a source of numerous growth factors which facilitate repair and healing. Thus platelet rich plasma has been increasingly used as a treatment modality in the field of reconstructive surgeries for wound healing. This preliminary study was carried out to explore whether platelet growth factors from platelet rich plasma could be used for enhancement of split thickness skin graft survival. Twenty patients (13 males and 7 females) requiring split thickness skin graft for various clinical reasons were enrolled in the study. Platelet rich plasma was collected by apheresis and frozen at -80° C. It was thawed at room temperature immediately before its intended application. PRP was applied only on one half of the wound, while another half served as control. Patient was followed for 6 weeks. The effect was assessed at first dressing in terms of graft uptake and subsequently as time taken for complete healing. There was 100% uptake of the graft in the area where platelet rich plasma was applied. In the control area, there was complete graft loss in 4 cases, partial loss in 7 cases and complete uptake in 9 cases. This study demonstrated promising results on application of PRP to split thickness skin grafts. Further randomized studies with greater sample size may be undertaken to establish platelet rich plasma as a validated treatment modality.

A Randomized Trial of the Effects of Nebulized Albuterol on Pulmonary Edema in Brain Dead Organ Donors

PubMed Central

Ware, Lorraine B.; Landeck, Megan; Koyama, Tatsuki; Zhao, Zhiguo; Singer, Jonathan; Kern, Ryan; Neidlinger, Nikole; Nguyen, John; Johnson, Elizabeth; Janz, David R.; Bernard, Gordon R.; Lee, Jae W.; Matthay, Michael A.

2013-01-01

Donor lung utilization rates are persistently low primarily due to donor lung dysfunction. We hypothesized that a treatment that enhances the resolution of pulmonary edema by stimulating the rate of alveolar fluid clearance would improve donor oxygenation and increase donor lung utilization. We conducted a randomized, blinded, placebo-controlled trial of aerosolized albuterol (5 mg q4h) versus saline placebo during active donor management in 506 organ donors. The primary outcome was change in oxygenation (PaO2/FiO2) from enrollment to organ procurement. The albuterol (n=260) and placebo (n=246) groups were well matched for age, gender, ethnicity, smoking, and cause of brain death. The change in PaO2/FiO2 from enrollment to organ procurement did not differ between treatment groups (p=0.54) nor did donor lung utilization (albuterol 29% vs. placebo 32%, p=0.44). Donors in the albuterol vs. placebo group were more likely to have the study drug dose reduced (13% vs. 1%, p<0.001) or stopped (8% vs. 0%, p<0.001) for tachycardia. In summary, treatment with high dose inhaled albuterol during the donor management period did not improve donor oxygenation or increase donor lung utilization but did cause tachycardia. High dose aerosolized albuterol should not be used in donors to enhance the resolution of pulmonary edema. PMID:24730050

Identification of platelet refractoriness in oncohematologic patients

PubMed Central

Ferreira, Aline Aparecida; Zulli, Roberto; Soares, Sheila; de Castro, Vagner; Moraes-Souza, Helio

2011-01-01

OBJECTIVES: To identify the occurrence and the causes of platelet refractoriness in oncohematologic patients. INTRODUCTION: Platelet refractoriness (unsatisfactory post-transfusion platelet increment) is a severe problem that impairs the treatment of oncohematologic patients and is not routinely investigated in most Brazilian services. METHODS: Forty-four episodes of platelet concentrate transfusion were evaluated in 16 patients according to the following parameters: corrected count increment, clinical conditions and detection of anti-platelet antibodies by the platelet immunofluorescence test (PIFT) and panel reactive antibodies against human leukocyte antigen class I (PRA-HLA). RESULTS: Of the 16 patients evaluated (median age: 53 years), nine (56%) were women, seven of them with a history of pregnancy. An unsatisfactory increment was observed in 43% of the transfusion events, being more frequent in transfusions of random platelet concentrates (54%). Platelet refractoriness was confirmed in three patients (19%), who presented immunologic and non-immunologic causes. Alloantibodies were identified in eight patients (50%) by the PIFT and in three (19%) by the PRA-HLA. Among alloimmunized patients, nine (64%) had a history of transfusion, and three as a result of pregnancy (43%). Of the former, two were refractory (29%). No significant differences were observed, probably as a result of the small sample size. CONCLUSION: The high rate of unsatisfactory platelet increment, refractoriness and alloimmunization observed support the need to set up protocols for the investigation of this complication in all chronically transfused patients, a fundamental requirement for the guarantee of adequate management. PMID:21437433

Dysmegakaryocytopoiesis and maintaining platelet count in patients with plasma cell neoplasm.

PubMed

Mair, Yasmin; Zheng, Yan; Cai, Donghong

2013-05-01

Dysmegakaryocytopoiesis in patients with the plasma cell neoplasm (PCN) is rarely discussed in the literature. The puzzling phenomenon, which PCN patients maintaining normal platelet count even when the marrow is mostly replaced by plasma cells, is hardly explored. This study was aimed to determine the frequency of dysmegakaryocytopoiesis in PCN and the relationships between bone marrow (BM) plasma cell percentage, plasma cell immunomarkers, the severity of dysmegakaryocytopoiesis, and peripheral blood platelet count in PCN. We randomly selected 16 cases of PCN, among which 4 were with monoclonal gammopathy of undetermined significance and 12 were with plasma cell myeloma. OUR STUDY SHOWED THAT: (1) Dysmegakaryocytopoiesis was present in all the selected cases of PCN and its severity was not correlated with the percentage of the plasma cells in BM; (2) almost all patients maintained normal platelet count even when BM was mostly replaced by plasma cells; (3) immunomarkers of the neoplastic plasma cells were not associated with dysmegakaryocytopoiesis or maintaining of platelet count. The possible mechanisms behind dysmegakaryocytopoiesis and maintaining of platelet count were also discussed. Despite the universal presence of dysmegakaryocytopoiesis in PCN, the platelet count is maintained at normal range.

An anti-von Willebrand factor aptamer reduces platelet adhesion among patients receiving aspirin and clopidogrel in an ex vivo shear-induced arterial thrombosis.

PubMed

Arzamendi, Dabit; Dandachli, Firas; Théorêt, Jean-François; Ducrocq, Gregory; Chan, Mark; Mourad, Walid; Gilbert, James C; Schaub, Robert G; Tanguay, Jean-François; Merhi, Yahye

2011-01-01

The von Willebrand factor (vWF) aptamer, ARC1779 that blocks the binding of vWF A1-domain to platelet glycoprotein 1b (GPIb) at high shear, may deliver a site-specific antithrombotic effect. We investigated the efficiency of ARC1779 on platelet function in patients with coronary artery disease (CAD) on double antiplatelet therapy. Blood from patients taking aspirin and clopidogrel and from normal volunteers was treated ex vivo with ARC1779 or abciximab, either prior to perfusion (pretherapy) or 10 minutes following the initiation of perfusion (posttherapy) on damaged arteries. Under pre- but not posttherapy, platelet adhesion was significantly reduced by ARC1779 at 83 and 250 nmol/L and by abciximab (100 nmol/L) versus placebo (4.8, 3.8, and 2.9 vs 7.3 platelets × 10(6)/cm(2), P < .05). In contrast to abciximab, ARC1779 did not significantly affect platelet aggregation, P-selectin expression, and platelet-leukocyte binding. These proof-of-concept data may constitute the framework for randomized clinical investigations of this novel antiplatelet therapy among patients with CAD.

Talin does not associate exclusively with alpha 2b beta 3 integrin in activated human platelets.

PubMed

Escolar, G; Diaz-Ricart, M; White, J G

1995-05-01

Talin is a high-molecular-weight protein that may stabilize connections between cytoplasmic actin and the submembrane portion of glycoprotein IIb-IIIa (GPIIb-IIIa) (alpha 2b beta 3 integrin) in thrombin-stimulated human platelets. Using morphologic and electrophoretic techniques, we have examined the association of talin with the cytoskeleton of platelets activated by thrombin in the presence of fibrinogen-coated gold particles (Fgn/Au). Ultrastructural studies confirmed the presence of Fgn/Au firmly bound to the outside membranes of detergent-extracted platelets. Immunoblots of protein bands showed GPIIIa, but not talin, associated with cytoskeletons of activated platelets. Immunogold cytochemical techniques were performed on ultrathin cryosections of whole platelets to localize talin at the ultrastructural level. Studies were performed on normal platelets and platelets defective in GPIIb-IIIa (Glanzmann's thrombasthenia) and GPIb (Bernard-Soulier syndrome). Talin was randomly distributed in the cytoplasm of resting platelets. Activation resulted in binding of Fgn/Au to the surface membrane and redistribution of talin to the submembrane region. However, no definitive colocalization between the two markers was noted. Activated thrombasthenic platelets failed to bind Fgn/Au, but talin was localized to the submembrane location. After activation, talin was confined to the submembrane zone of Bernard-Soulier syndrome platelets. No definitive colocalization was observed between large clusters of Fgn/Au-occupied receptors and talin distributed in the submembrane region. GPIb and GPIIb-IIIa are not necessary for talin to localize in the submembrane region of activated cells. Talin does not redistribute exclusively with GPIIb-IIIa, and it may stabilize connections with other glycoproteins.

Dark chocolate inhibits platelet isoprostanes via NOX2 down-regulation in smokers.

PubMed

Carnevale, R; Loffredo, L; Pignatelli, P; Nocella, C; Bartimoccia, S; Di Santo, S; Martino, F; Catasca, E; Perri, L; Violi, Francesco

2012-01-01

Dark chocolate is reported to decrease platelet activation but the underlying mechanism is still undefined. Dark chocolate is rich in polyphenols that could exert an antiplatelet action via inhibition of oxidative stress. The aim of the present study was to assess if dark chocolate inhibits platelet reactive oxidant species (ROS) formation and platelet activation. Twenty healthy subjects (HS) and 20 smokers were randomly allocated to receive 40 g of dark (cocoa > 85%) or milk chocolate (cocoa < 35%) in a cross-over, single-blind study. There was an interval of 7 days between the two phases of the study. At baseline and 2 h after chocolate ingestion, platelet recruitment (PR), platelet ROS, platelet isoprostane 8-ISO-prostaglandin F2α (8-iso-PGF2α), Thromboxane (TxA2) and platelet activation of NOX2, the catalytic sub-unit of NADPH oxidase, and serum epicatechin were measured. Compared with HS, smokers showed enhanced PR, platelet formation of ROS and eicosanoids and NOX2 activation. After dark chocolate, platelet ROS (-48%, P < 0.001), 8-iso-PGF2α (-10%, P < 0.001) and NOX2 activation (-22%, P < 0.001) significantly decreased; dark chocolate did not affect platelet variables in HS. No effect of milk chocolate was detected in both groups. Serum epicatechin increased after dark chocolate in HS (from 0.454 ± 0.3 nm to 118.3 ± 53.7 nm) and smokers (from 0.5 ± 0.28 nm to 120.9 ± 54.2 nm). Platelet incubation with 0.1-10 μm catechin significantly reduced PR, platelet 8-iso-PGF2α and ROS formation and NOX2 activation only in platelets from smokers. Dark chocolate inhibits platelet function by lowering oxidative stress only in smokers; this effect seems to be dependent on its polyphenolic content. © 2011 International Society on Thrombosis and Haemostasis.

Failure of platelet parameters and biomarkers to correlate platelet function to severity and etiology of heart failure in patients enrolled in the EPCOT trial. With special reference to the Hemodyne hemostatic analyzer. Whole Blood Impedance Aggregometry for the Assessment of Platelet Function in Patients with Congestive Heart Failure.

PubMed

Serebruany, Victor L; McKenzie, Marcus E; Meister, Andrew F; Fuzaylov, Sergey Y; Gurbel, Paul A; Atar, Dan; Gattis, Wendy A; O'Connor, Christopher M

2002-01-01

Data from small studies have suggested the presence of platelet abnormalities in patients with congestive heart failure (CHF). We sought to characterize the diagnostic utility of different platelet parameters and platelet-endothelial biomarkers in a random outpatient CHF population investigated in the EPCOT ('Whole Blood Impedance Aggregometry for the Assessment of Platelet Function in Patients with Congestive Heart Failure') Trial. Blood samples were obtained for measurement of platelet contractile force (PCF), whole blood aggregation, shear-induced closure time, expression of glycoprotein (GP) IIb/IIIa, and P-selectin in 100 consecutive patients with CHF. Substantial interindividual variability of platelet characteristics exists in patients with CHF. There were no statistically significant differences when patients were grouped according to incidence of vascular events, emergency revascularization needs, survival, or etiology of heart failure. Aspirin use did not affect instrument readings either. PCF correlates very poorly with whole blood aggregometry (r(2) = 0.023), closure time (r(2) = 0.028), platelet GP IIb/IIIa (r(2) = 0.0028), and P-selectin (r(2) = 0.002) expression. Furthermore, there was no correlation with brain natriuretic peptide concentrations, a marker of severity and prognosis in heart failure reflecting the neurohumoral status. Patients with heart failure enrolled in the EPCOT Trial exhibited a marginal, sometimes oppositely directed change in platelet function, challenging the diagnostic utility of these platelet parameters and biomarkers to serve as useful tools for the identification of platelet abnormalities, for predicting clinical outcomes, or for monitoring antiplatelet strategies in this population. The usefulness of these measurements for assessing platelets in the different clinical settings remains to be explored. Taken together, opposite to our expectations, major clinical characteristics of heart failure did not correlate well with the platelet characteristics investigated in this study. Copyright 2002 S. Karger AG, Basel

Effects of combination treatment with policosanol and omega-3 fatty acids on platelet aggregation: A randomized, double-blind clinical study

PubMed Central

Castaño, Gladys; Arruzazabala, Maria L.; Fernández, Lilia; Mas, Rosa; Carbajal, Daisy; Molina, Vivian; Illnait, José; Mendoza, Sarahí; Gámez, Rafael; Mesa, Melbis; Fernández, Julio

2006-01-01

Background: Policosanol is a mixture of long-chain primary aliphatic alcoholspurified from sugar cane wax that has cholesterol lowering and antiplatelet effects. Omega-3 fatty acids (FA) have triglyceride lowering and antiplatelet effects. Combination treatment with policosanol and omega-3 FA (Ω23FA) has been associated with significant inhibition of platelet aggregation in rabbits compared with either drug alone. Objective: The aim of this study was to investigate the effects of combination treatment with Ω3FA (1 g/d) and policosanol (Ω3FA+Poli) compared with Ω3FA (1 g/d) plus placebo (Ω3FA+Pla) on platelet aggregation in human patients with hypercholesterolemia. Methods: This randomized, double-blind, clinical study at the Surgical Medical Research Center (Havana City, Cuba) recruited outpatients from lipid clinics, with some atherosclerotic risk factors. Outpatients of both sexes aged 20 to 75 years with serum total cholesterol (TC) levels ≥5 and <6 mmol/L were eligible to enroll. They were included in the study at the end of a 4-week diet stabilization period if their platelet aggregation to arachidonic acid (AA) was ≥50% and serum TC level remained ≥5 mmol/L. Patients were then evenly randomized to receive Ω3FA (1 g/d) + placebo or Ω3FA (1 g/d) + policosanol (10 mg/d) to be taken PO with the evening meal for 21 days. Treatment was assigned according to a randomization code using balanced blocks and a 1:1 allocation ratio. Inhibition of platelet aggregation to AA was the primary efficacy variable, while effects on platelet aggregation to collagen and epinephrine and on lipid profile were secondary variables. Drug compliance and adverse events (AEs) were monitored. Tolerability was assessed using physical examinations and laboratory test results. Results: Sixty-four subjects were initially enrolled. Fifty-four patients (30 women, 24 men; mean [SD] age, 58.4 [12] years, [range, 40–70 years]) met the inclusion criteria and were randomized to treatment; 2 groups of 27. After 21 days, platelet aggregation to AA was significantly inhibited in the 2 groups. Ω3FA+Poli inhibited platelet aggregation to all agonists by ≥20%. Platelet aggregation to AA 1.0 and 1.5 mM was inhibited with combination treatment (39.6% and 33.9%, respectively; both P < 0.001 vs baseline; P < 0.001 and P < 0.01, respectively, vs Ω3FA+Pla) and with Ω3FA+Pla (11.0% and 13.3%; both, P < 0.001). Combination treatment was more effective in inhibiting platelet aggregation to AA 1.0 and 1.5 mM in 28.6% (P < 0.001) and 20.6% (P < 0.01), respectively. Platelet aggregation to collagen 1 μg/mL was significantly inhibited with combination treatment and with Ω3FA+Pla compared with baseline (43.2% and 15.1%, respectively; both, P < 0.001), but the effects of combination treatment were significantly greater (P < 0.01). Platelet aggregation to epinephrine 0.1 mM was inhibited with Ω3FA+Poli and Ω3FA+Pla (34.8% and 20.1%; both, P < 0.001), with similar results for both groups. Bleeding time did not change significantly for either group and Ω3FA+Pla did not significantly change the lipid profile. Combination treatment did significantly reduce levels of low-density lipoprotein cholesterol (LDL-C) (17.4%; P < 0.001 vs baseline, P < 0.05 vs Ω3FA+Pla) and TC (10.1%; P < 0.001 vs baseline, P < 0.05 vs Ω3FA+Pla), increase high-density lipoprotein cholesterol (HDL-C) levels (18.0%; P < 0.001 vs baseline), but did not significantly change triglyceride levels. Three patients (2 from the Ω3FA+Poli group and 1 from the Ω3FA+Pla group) withdrew from the trial, though none were due to AEs. Two patients receiving combination treatment reported mild AEs (headache). All treatments were well tolerated. Conclusions: In these patients, policosanol (10 mg/d) administered concomitantly with Ω3FA (1 g/d) enhanced the inhibition of platelet aggregation to AA and collagen, but not to epinephrine, compared with Ω3FA+Pla, without significantly affecting bleeding time. Concomitant treatment was also associated with reduced levels of LDL-C and TC and raised HDL-C levels. All treatments were well tolerated. PMID:24678094

The TALKS study to improve communication, logistical, and financial barriers to live donor kidney transplantation in African Americans: protocol of a randomized clinical trial.

PubMed

Strigo, Tara S; Ephraim, Patti L; Pounds, Iris; Hill-Briggs, Felicia; Darrell, Linda; Ellis, Matthew; Sudan, Debra; Rabb, Hamid; Segev, Dorry; Wang, Nae-Yuh; Kaiser, Mary; Falkovic, Margaret; Lebov, Jill F; Boulware, L Ebony

2015-10-09

Live donor kidney transplantation (LDKT), an optimal therapy for many patients with end-stage kidney disease, is underutilized, particularly by African Americans. Potential recipient difficulties initiating and sustaining conversations about LDKT, identifying willing and medically eligible donors, and potential donors' logistical and financial hurdles have been cited as potential contributors to race disparities in LDKT. Few interventions specifically targeting these factors have been tested. We report the protocol of the Talking about Living Kidney Donation Support (TALKS) study, a study designed to evaluate the effectiveness of behavioral, educational and financial assistance interventions to improve access to LDKT among African Americans on the deceased donor kidney transplant recipient waiting list. We adapted a previously tested educational and social worker intervention shown to improve consideration and pursuit of LDKT among patients and their family members for its use among patients on the kidney transplant waiting list. We also developed a financial assistance intervention to help potential donors overcome logistical and financial challenges they might face during the pursuit of live kidney donation. We will evaluate the effectiveness of these interventions by conducting a randomized controlled trial in which patients on the deceased donor waiting list receive 1) usual care while on the transplant waiting list, 2) the educational and social worker intervention, or 3) the educational and social worker intervention plus the option of participating in the financial assistance program. The primary outcome of the randomized controlled trial will measure potential recipients' live kidney donor activation (a composite rate of live donor inquiries, completed new live donor evaluations, or live kidney donation) at 1 year. The TALKS study will rigorously assess the effectiveness of promising interventions to reduce race disparities in LDKT. NCT02369354.

Motivating first-time, group O blood donors to return: Rationale and design of a randomized controlled trial of a post-donation telephone interview

PubMed Central

France, Janis L.; France, Christopher R.; Carlson, Bruce W.; Kessler, Debra A.; Rebosa, Mark; Shaz, Beth H.; Madden, Katrala; Carey, Patricia M.

2015-01-01

First-time blood donors are essential to the US donor pool, providing nearly a third of all donations. Unfortunately, there are a wide variety of obstacles to repeat donation and new donors are extremely difficult to retain. Because each donor experiences a unique set of deterrents, we developed a post-donation interview based on motivational interview principles in order to flexibly address individual barriers. The primary aim of this randomized clinical trial is to examine retention of first-time, group O blood donors who are randomly assigned to receive either a telephone-delivered interview with motivational and action planning components or a standard-of-care control call approximately six weeks after their donation. Measures of donation attitude, perceived behavioral control, intention, and motivational autonomy will be measured before and after the telephone contact using online surveys, and donation attempts will be tracked for one year using blood center donor databases. We hypothesize that, compared to controls, donors who receive the telephone interview will be more likely to make a donation attempt over the following year. In addition, we will examine possible mechanisms of action of the interview using key predictors of donation behavior as described by Self Determination Theory (i.e., motivational autonomy) and the Theory of Planned Behavior (i.e., attitude, perceived behavioral control, and intention). Results of this intervention may help to support a novel strategy to enhance retention of selected blood donors in an effort to better meet the nation’s blood supply needs. PMID:26247570

Hematological characteristics in neonates with twin anemia-polycythemia sequence (TAPS).

PubMed

Lopriore, E; Slaghekke, F; Oepkes, D; Middeldorp, J M; Vandenbussche, F P H A; Walther, F J

2010-03-01

To evaluate the neonatal hematological features of monochorionic twins with twin anemia-polycythemia sequence (TAPS) and to determine the additional diagnostic value of reticulocyte count measurement. A cohort of consecutive monochorionic twins with TAPS (n = 19) was included in the study and each twin pair was compared with two monochorionic twin pairs (n = 38) unaffected by TAPS or twin-twin transfusion syndrome (TTTS), matched for gestational age at birth. We measured full blood counts on day 1 and determined the incidence of anemia, polycythemia, reticulocytosis and thrombocytopenia. Median inter-twin hemoglobin (Hb) difference in monochorionic twins with and without TAPS was 13.7 g/dL and 2.4 g/dL, respectively (p < 0.01). Median inter-twin reticulocyte count ratio in twins with and without TAPS was 3.1 and 1.0, respectively (p < 0.01). Thrombocytopenia (platelet count < 150 x 10(9)/L) occurred more often in the TAPS group than in the control group, 45% (17/38) versus 11% (11/38), respectively (p < 0.01). In the TAPS group, mean platelet count was significantly lower in recipients than in donors, 133 x 10(9)/L versus 218 x 10(9)/L, respectively (p < 0.01). TAPS twins have a large inter-twin Hb difference in combination with a large inter-twin reticulocyte count ratio. Recipients are more often thrombocytopenic than donors, probably due to polycythemia. Copyright (c) 2010 John Wiley & Sons, Ltd.

Randomized trial comparing 600- with 300-mg loading dose of clopidogrel in patients with non-ST elevation acute coronary syndrome undergoing percutaneous coronary intervention: results of the Platelet Responsiveness to Aspirin and Clopidogrel and Troponin Increment after Coronary intervention in Acute coronary Lesions (PRACTICAL) Trial.

PubMed

Yong, Gerald; Rankin, Jamie; Ferguson, Louise; Thom, Jim; French, John; Brieger, David; Chew, Derek P; Dick, Ron; Eccleston, David; Hockings, Bernard; Walters, Darren; Whelan, Alan; Eikelboom, John W

2009-01-01

There is uncertainty about the benefit of a higher loading dose (LD) of clopidogrel in patients with non-ST elevation acute coronary syndrome (NSTEACS) undergoing early percutaneous coronary intervention (PCI). We compared the effects of a 600- versus a 300-mg LD of clopidogrel on inhibition of platelet aggregation, myonecrosis, and clinical outcomes in patients with NSTEACS undergoing an early invasive management strategy. Patients with NSTEACS (n = 256, mean age 63 years, 81.6% elevated troponin) without thienopyridine for at least 7 days were randomized to receive 600- or 300-mg LD of clopidogrel. Percutaneous coronary intervention was performed in 140 patients, with glycoprotein IIb/IIIa inhibitor use in 68.6%. Adenosine diphosphate (ADP)-induced platelet aggregation was measured by optical platelet aggregometry immediately before coronary angiography. Post-PCI myonecrosis was defined as a next-day troponin I greater than 5 times the upper limit of reference range and greater than baseline levels. Clopidogrel 600-mg LD compared with 300-mg LD was associated with significantly reduced ADP-induced platelet aggregation (49.7% vs 55.7% with ADP 20 micromol/L) but did not reduce post-PCI myonecrosis or adverse clinical outcomes to 6 months. There was no association between preprocedural platelet aggregation and outcome. These data confirm a modest incremental antiplatelet effect of a 600-mg clopidogrel LD compared with 300-mg LD but provide no support for a clinical benefit in patients with NSTEACS managed with an early invasive strategy including a high rate (69%) of glycoprotein IIb/IIIa inhibitor use during PCI.

Therapeutic potential of choline magnesium trisalicylate as an alternative to aspirin for patients with bleeding tendencies.

PubMed

Danesh, B J; Saniabadi, A R; Russell, R I; Lowe, G D

1987-12-01

We have compared the effects of acetyl salicylic acid (ASA, aspirin) and choline magnesium trisalicylate (CMT), a non-acetylated salicylate product, on platelet aggregation in human whole blood ex-vivo. Using a whole blood platelet counter, platelet aggregation was quantified by measuring the fall in the number of single platelets at peak aggregation in response to collagen, arachidonic acid (AA), as well as spontaneous aggregation. In double blind and random order, 12 healthy volunteers received, on two separate occasions 10 days apart, a single oral dose of 652 mg ASA or 655 mg CMT. Despite a comparable absorption of salicylic acid from the two drugs, ingestion of ASA resulted in a marked inhibition of platelet aggregation induced by collagen (p less than 0.005), AA (p less than 0.01) and spontaneous aggregation (p less than 0.01), whereas such effects were not observed after CMT ingestion. We suggest that CMT may have therapeutic potential as an alternative to aspirin when inhibition of platelet aggregation can induce bleeding complications.

Hematologic adverse effects of 2 different polyclonal antilymphocyte preparations in de novo kidney transplant patients.

PubMed

Rostaing, Lionel; Lavayssière, Laurence; Kamar, Nassim

2010-06-01

To evaluate the hematologic adverse effects of polyclonal antilymphocyte globulins within the first month after surgery in kidney transplant recipients. In this prospective, randomized trial, we included 16 adult-sensitized (panel-reactive antibodies > 30%) recipients of a kidney from a deceased donor. Eight patients received therapy with Genzyme (Thymoglobulin: ATG-G; 6.2 +/- 2.9 mg/kg for 7 days), and 8 patients received Fresenius (Lymphoglobulin: ATG-F; 22.6 +/- 7.9 mg/kg for 6 days). Other immunosuppressants included mycophenolate mofetil, tacrolimus, and steroids. Platelet counts were normal before transplant and significantly reduced after transplant; however, this was more pronounced in ATG-F patients, and had normalized by day 7 in the ATG-G and by day 10 in the ATG-F groups. Mean leukocyte/polymorphonuclear cell counts remained within the normal range in both groups through follow-up. Hemoglobin levels were similar at approximately 10 g/dL for both groups, up to day 10. However, erythropoietin-stimulating-agent therapy had been given to more patients in the ATG-F group than patients in the ATG-G group. Reticulocyte counts were significantly lower in ATG-F patients by days 3, 5, 7, and 10. From day 14 onwards, reticulocyte counts were similar in both groups. With regard to lymphocyte counts, these were normal in both groups before transplant and then significantly decreased afterward. No patient presented with acute rejection or serum-sickness disease. Reduced platelet and reticulocyte counts occur more frequently immediately after transplant when using ATG-F compared with ATG-G therapy. Consequently, erythropoietin-stimulating-agent therapy was needed more often for ATG-F patients.

Informed consent in research to improve the number and quality of deceased donor organs.

PubMed

Rey, Michael M; Ware, Lorraine B; Matthay, Michael A; Bernard, Gordon R; McGuire, Amy L; Caplan, Arthur L; Halpern, Scott D

2011-02-01

Improving the management of potential organ donors in the intensive care unit could meet an important public health goal by increasing the number and quality of transplantable organs. However, randomized clinical trials are needed to quantify the extent to which specific interventions might enhance organ recovery and outcomes among transplant recipients. Among several barriers to conducting such studies are the absence of guidelines for obtaining informed consent for such studies and the fact that deceased organ donors are not covered by extant federal regulations governing oversight of research with human subjects. This article explores the underexamined ethical issues that arise in the context of donor management studies and provides ethical guidelines and suggested regulatory oversight mechanisms to enable such studies to be conducted ethically. We conclude that both the respect that is traditionally accorded to the prior wishes of the dead and the possibility of postmortem harm support a role for surrogate consent of donors in such randomized controlled trials. Furthermore, although recipients will often be considered human subjects under federal regulations, several ethical arguments support waiving requirements for recipient consent in donor management randomized controlled trials. Finally, we suggest that new regulatory mechanisms, perhaps linked to existing regional and national organ donation and transplantation infrastructures, must be established to protect patients in donor management studies while limiting unnecessary barriers to the conduct of this important research.

Enhancement of nitric oxide release and hemocompatibility by surface chirality of D-tartaric acid grafting

NASA Astrophysics Data System (ADS)

Han, Honghong; Wang, Ke; Fan, Yonghong; Pan, Xiaxin; Huang, Nan; Weng, Yajun

2017-12-01

Nitric Oxide (NO) generation from endogenous NO-donors catalyzed by diselenide modified biomaterials has been reported. Here we reported surface chirality by L-tartaric acid and D-tartaric acid grafting on the outermost showed a significant impact on diselenide modified biomaterials, which modulated protein adsorption, NO release and anti-platelet adhesion properties. D-tartaric acid grafted surface showed more blood protein adsorption than that of L-surfaces by QCM analysis, however, ELISA analysis disclosed less fibrinogen denatured on the D surfaces. Due to the surface ratio of selenium decreasing, NO release catalyzed by L-tartaric acid grafting on the outermost significantly decreased in comparison to that of only selenocystamine immobilized surfaces. While NO release catalyzed by D-tartaric acid grafting on the outermost didn't decrease and was similar with that of selenocystamine immobilized surfaces. Surface chirality combined with NO release had synergetic effects on platelet adhesion, and it showed the lowest number of platelets adhered on the D-tartaric acid grafted surfaces. Thus surface chirality from D-tartaric acid grafting enhanced hemocompatibility of the surface in this study. Our work provides new insights into engineering novel blood contacting biomaterials by taking into account surface chirality.

Assessment of platelet function in healthy cats in response to commonly prescribed antiplatelet drugs using three point-of-care platelet function tests.

PubMed

Ho, Kimberly K; Abrams-Ogg, Anthony Cg; Wood, R Darren; O'Sullivan, M Lynne; Kirby, Gordon M; Blois, Shauna L

2017-06-01

Objectives The objective was to determine if decreased platelet function could be detected after treatment with aspirin and/or clopidogrel in healthy cats using three point-of-care platelet function tests that evaluate platelet function by different methods: Multiplate (by impedance), Platelet Function Analyzer 100 (by mechanical aperture closure) and Plateletworks (by platelet counting). Methods Thirty-six healthy cats were randomly assigned to receive one of three oral treatments over an 8 day period: (1) aspirin 5 mg q72h; (2) aspirin 20.25 mg q72h; or (3) clopidogrel 18.75 mg q24h. Cats treated with 5 and 20.25 mg aspirin also received clopidogrel on days 4-8. Platelet aggregation in response to adenosine diphosphate and collagen ± arachidonic acid was assessed on days 1 (baseline), 4 and 8. Aspirin and clopidogrel metabolites were measured by high-performance liquid chromatography. Platelet function in response to treatment was analyzed by ANCOVA, linear regression and Spearman correlation. Results The only solitary aspirin effect was detected using Plateletworks with collagen in cats treated with 20.25 mg. The only effect detected by Multiplate was using arachidonic acid in cats treated with both aspirin 20.25 mg and clopidogrel. All clopidogrel treatment effects were detected by Platelet Function Analyzer 100, Plateletworks (adenosine diphosphate) and Plateletworks (collagen). Drug metabolites were present in all cats, but concentrations were minimally correlated to platelet function test results. Conclusions and relevance Platelet Function Analyzer 100 and Plateletworks using adenosine diphosphate ± collagen agonists may be used to detect decreased platelet function in response to clopidogrel treatment. Either aspirin is not as effective an antiplatelet drug as clopidogrel, or the tests used were not optimal to measure aspirin effect. Cats with heart disease are commonly prescribed antiplatelet drugs to decrease the risk of aortic thromboembolism. Platelet Function Analyzer 100 and Plateletworks may be useful for confirming clopidogrel treatment in these cats.

First Trimester Hemolysis, Elevated Liver Enzymes, Low Platelets Syndrome in a Surrogate Pregnancy.

PubMed

Myer, Emily; Hill, James

2015-10-01

Background The occurrence of hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome before 20 weeks of gestation is rare. HELLP is a possible but rare syndrome in gestational surrogate pregnancies for surrogates with risk factors for development of preeclampsia. Case A 32-year-old patient with chronic hypertension and positive antinuclear antibody presented for prenatal care at 13 weeks and 1 day. She was a surrogate for the embryo of a 43-year-old couple. By 15 weeks she developed uncontrolled hypertension requiring hospitalization. She was expectantly managed until her condition deteriorated. At 16 weeks and 1 day she developed hemolysis, elevated liver enzymes, thrombocytopenia, and fetal demise. Conclusions HELLP syndrome is rare and carries a significant morbidity and mortality for the mother and fetus. Clinicians should encourage the surrogate to share her medical history with the embryo donor for appropriate counseling on pregnancy risks.

Health-Related Fitness in the Royal Netherlands Army

DTIC Science & Technology

2009-10-01

autologous platelet - rich plasma application in traumatic tendon injuries, [7] and collagen hydrolysate in joint pain [8]. 3.0 LIFESTYLE-RELATED HEALTH...randomized controlled trial. Arch Phys Med Rehabil 2008;89:1675-85. [7] Mos de M, Windt van der AE, Jahr H, et al. Can platelet - rich plasma enhance tendon...devices (leg press, chest press, shoulder press, vertical traction) and cardio-stepper (progressive protocol), according to gender- and age- specific

IMITS: Information and Clinical Technologies for the Advancement of Healthcare

DTIC Science & Technology

2008-12-01

a model to evaluate the efficacy of Platelet Gel Therapy on non-healing diabetic foot wounds... the safety and efficacy of Platelet Gel Therapy on non-healing diabetic lower extremity wounds. The implementation of the study protocol, “ A Randomized...prototype for select MTFs. One of the initial steps within Phase Two will be for the DWA project team to provide a project review at SGR

The Distinction of Amyloid-β Protein Precursor (AβPP) Ratio in Platelet Between Alzheimer's Disease Patients and Controls: A Systematic Review and Meta-Analysis.

PubMed

Shi, Yachen; Gu, Lihua; Alsharif, Abdul Azeez; Zhang, Zhijun

2017-01-01

To systematically assess the clinical significance of platelet amyloid-β protein precursor (AβPP) ratio between Alzheimer's disease (AD) patients and controls. 14 articles were selected in this analysis by search of databases including PubMed and Web of Science up to December 2016. Random effects models were used to calculate the standardized mean difference (SMD). Subgroup analyses were used to detect the cause of heterogeneity. The result showed a significant drop in platelet AβPP ratio in AD patients compared to controls [SMD: -1.871; 95% CI: (-2.33, -1.41); p < 0.001; I2 = 88.0% ]. Subgroup analysis revealed races or the quality of studies may be the cause of high heterogeneity. This meta-analysis concluded that there is a close association between platelet AβPP ratio and AD. It is necessary to design a sizable sample study to further support that platelet AβPP ratio can be a biomarker of AD.

Platelet-Rich Plasma for Frozen Shoulder: A Case Report.

PubMed

Aslani, Hamidreza; Nourbakhsh, Seyed Taghi; Zafarani, Zohreh; Ahmadi-Bani, Monireh; Ananloo, Mohammad Ebrahim Shahsavand; Beigy, Maani; Salehi, Shahin

2016-01-01

Frozen shoulder is a glenohumeral joint disorder that movement because of adhesion and the existence of fibrosis in the shoulder capsule. Platelet-rich plasma can produce collagen and growth factors, which increases stem cells and consequently enhances the healing. To date, there is no evidence regarding the effectiveness of platelet-rich plasma in frozen shoulder. A 45-year-old man with shoulder adhesive capsulitis volunteered for this treatment. He underwent two consecutive platelet-rich plasma injections at the seventh and eighth month after initiation of symptoms. We measured pain, function, ROM by the visual analogue scale (VAS), scores from the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and goniometer; respectively. After first injection, the patient reported 60% improvement regarding diurnal shoulder pain, and no night pain. Also, two-fold improvement for ROM and more than 70% improvement for function were reported. This study suggests the use of platelet-rich plasma in frozen shoulder to be tested in randomized trials.

A randomized, prospective study of laparoendoscopic single-site plus one-port versus mini laparoscopic technique for live donor nephrectomy.

PubMed

Lee, Kyu Won; Choi, Sae Woong; Park, Yong Hyun; Bae, Woong Jin; Choi, Yong Sun; Ha, U-Syn; Hong, Sung-Hoo; Lee, Ji Youl; Kim, Sae Woong; Cho, Hyuk Jin

2018-04-01

To compare the clinical outcomes of laparoendoscopic single-site plus one-port donor nephrectomy (LESSOP-DN) and mini laparoscopic donor nephrectomy (MLDN). A prospective randomized controlled trial was conducted from December 2014 to February 2016 in donors scheduled for left donor nephrectomy. Donor and recipient demographics and clinical outcomes including pain scores and questionnaires (BIQ: body image questionnaire, SF-36, patient-reported overall convalescence) were also compared. A total of 121 eligible donors were recruited, of which 99 donors who were scheduled to undergo an operation on their left side were randomized into LESSOP-DN (n = 50) and MLDN (n = 49) groups. There were no significant demographic differences between the two groups. The renal extraction time in the LESS-DN group was shorter than that in the MLDN group (75.89 ± 13.01 vs. 87.31 ± 11.38 min, p < 0.001). Other perioperative parameters and complication rates were comparable between the two groups. The LESSOP-DN group had a smaller incision length than the MLDN group (4.89 ± 0.68 vs. 6.21 ± 1.11 cm, p < 0.001), but cosmetic scores and body image scores were similar in the two groups (p = 0.905, 0.217). Donor quality of life (SF-36) and recovery and satisfaction data were comparable between the two groups. Delayed graft function (DGF) occurred in one recipient undergoing MLDN procedure (2.1%) and progressed to graft failure. There were no differences in cosmetic satisfaction between groups despite the smaller incision size of LESSOP-DN. Safety parameters and subjective measures of postoperative morbidity were similar between the two groups.

Impaired contraction of blood clots as a novel prothrombotic mechanism in systemic lupus erythematosus.

PubMed

Le Minh, Giang; Peshkova, Alina D; Andrianova, Izabella A; Sibgatullin, Timur B; Maksudova, Adelia N; Weisel, John W; Litvinov, Rustem I

2018-01-31

The aim of this work was to examine a possible role of clot contraction/retraction in thrombotic complications of systemic lupus erythematosus (SLE). Using a novel automated method, we investigated kinetics of clot contraction in the blood of 51 SLE patients and 60 healthy donors. The functionality of platelets in the SLE patients was assessed using flow cytometry by expression of P-selectin and fibrinogen-binding capacity. The rate and degree of clot contraction were significantly reduced in SLE patients compared with healthy subjects, especially in the patients with higher blood levels of anti-dsDNA antibodies. The reduced platelet contractility correlated with partial refractoriness of platelets isolated from the blood of SLE patients to stimulation induced by the thrombin receptor activating peptide. To test if the anti-dsDNA autoantibodies cause continuous platelet activation, followed by exhaustion and dysfunction of the cells, we added purified exogenous anti-dsDNA autoantibodies from SLE patients to normal blood before clotting. In support of this hypothesis, the antibodies first enhanced clot contraction and then suppressed it in a time-dependent manner. Importantly, a direct correlation of clot contraction parameters with the disease severity suggests that the reduced compactness of intravascular clots and thrombi could be a pathogenic factor in SLE that may exaggerate the impaired blood flow at the site of thrombosis. In conclusion, autoantibodies in SLE can affect platelet contractility, resulting in reduced ability of clots and thrombi to shrink in volume, which increases vessel obstruction and may aggravate the course and outcomes of thrombotic complications in SLE. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Comparison of the platelet-rich plasma and buffy coat protocols for preparation of canine platelet concentrates.

PubMed

Hoareau, Guillaume L; Jandrey, Karl E; Burges, Julie; Bremer, Daphne; Tablin, Fern

2014-12-01

Platelet (PLT) concentrates (PC) can be produced via the buffy coat (BC) or platelet-rich plasma (PRP) protocols. The 2 methods have not been compared with canine blood. The aims of the study were to compare the PLT, WBC, and RBC concentrations, in vitro PLT function, and markers of platelet storage lesion (PSL) in canine PC generated by 2 different protocols, and determine microbial growth throughout storage. PC from 8 healthy donor dogs were produced using 2 standard protocols, PRP and BC. PLT, WBC, and RBC counts, optical aggregometry assays, and PSL markers (pH, pCO2 , HCO3 , lactate and glucose concentrations, and LDH activity) were determined on storage days 0, 1, 3, 5, and 7. Aerobic and anaerobic bacterial cultures were also performed. Mean PLT counts were comparable between protocols and remained stable throughout storage up to day 7, while median WBC and RBC counts on day 0 were significantly higher in the BC-PC group (17,800 WBCs/μL; 195,000 RBCs/μL) than in the PRP-PC group (200 WBCs/μL; 10,000 RBCs/μL) (P = .012). In PRP-PC aggregometry, the median slope and amplitude in response to γ-thrombin and convulxin (+ ADP) were significantly decreased, and virtually absent in BC-PC during storage. PSL markers (lactate, LDH activity) were higher in BC-PC. Aerobic bacterial growth was observed in 2 PRP-PC and 1 BC-PC. This in vitro study suggests that PRP-PC had lesser WBC and RBC contamination and superior PLT function compared with BC-PC. In vivo studies are required to address safety and efficacy of PRP-PC. © 2014 American Society for Veterinary Clinical Pathology.

Preclinical and clinical studies on the use of growth factors for bone repair: a systematic review.

PubMed

Fisher, Daniel Mark; Wong, James Min-Leong; Crowley, Conor; Khan, Wasim S

2013-05-01

Bone healing is a complex process. Whilst the majority of fractures heal with conventional treatment, open fractures, large bone defects and non unions still provide great challenges to Orthopaedic Surgeons. Whilst autologous bone graft is seen as the gold standard, the use of growth factors is a growing area of research to find an effective alternative with lower side effects such as donor site morbidity and the finite amount available. This systematic review aims to summarize the pre clinical in-vivo studies and examine the clinical studies on the use of growth factors in bone healing. Databases: PubMed, Medline, OVID, and Cochrane library. The following key words and search terms were used: Growth Factors, Bone Healing, Bone Morphogenic Protein, Transforming Growth Factor Beta, Insulin Like Growth Factor, Platelet Derived Growth Factor, Fracture. All articles were screened based on title with abstracts and full text articles reviewed as appropriate. Reference lists were reviewed from relevant articles to ensure comprehensive and systematic review. Three tables of studies were constructed focussing on Bone Morphogenic Proteins, Platelet Rich Plasma and Growth Factors and Tissue Engineering. Bone Morphogenic Proteins and Platelet Rich Plasma, which contains multiple growth factors, have been shown in preclinical and clinical trials to be an effective alternative to autologous bone graft. Bone Morphogenic Proteins have been shown to be effective in fracture non union, and in open tibial fractures. Platelet Rich Plasma has shown promise in preclinical trials and some small clinical trials, however numbers are limited. Bone Morphogenic Proteins have been shown to be superior to Platelet Rich Protein in one trial. Combining these growth factors with tissue engineering techniques is the focus of ongoing research, and through further clinical trials the most effective techniques for enhancing bone healing will be revealed.

Hemocompatibility Comparison of Biomedical Grade Polymers Using Rabbit Thrombogenicity Model for Preparing Nonthrombogenic Nitric Oxide Releasing Surfaces

PubMed Central

Handa, Hitesh; Major, Terry C.; Brisbois, Elizabeth J.; Amoako, Kagya A.; Meyerhoff, Mark E.; Bartlett, Robert H.

2014-01-01

Nitric oxide (NO) is an endogenous vasodilator as well as natural inhibitor of platelet adhesion/activation. Nitric oxide releasing (NOrel) materials can be prepared by doping an NO donor species, such as diazeniumdiolated dibutylhexanediamine (DBHD/N2O2), within a polymer coating. The inherent hemocompatibility properties of the base polymer can also influence the efficiency of such NO release coatings. In this study, four biomedical grade polymers were evaluated in a 4 h rabbit model of thrombogenicity for their effects on extracorporeal circuit thrombus formation and circulating platelet count. At the end of 4 h, Elast-Eon E2As was found to preserve 58% of baseline platelets versus 48, 40, and 47% for PVC/DOS, Tecophilic SP-60D-60, and Tecoflex SG80A, respectively. Elast-Eon also had significantly lower clot area of 5.2 cm2 compared to 6.7, 6.1, and 6.9 cm2 for PVC/DOS, SP-60D-60, and SG80A, respectively. Based on the results obtained for the base polymer comparison study, DBHD/N2O2-doped E2As was evaluated in short-term (4 h) rabbit studies to observe the NO effects on prevention of clotting and preservation of platelet function. Platelet preservation for this optimal NO release formulation was 97% of baseline after 4 h, and clot area was 0.9 cm2 compared to 5.2 cm2 for controls, demonstrating that combining E2As with NO release provides a truly advanced hemocompatible polymer coating for extracorporeal circuits and potentially other blood contacting applications. PMID:24634777

Granulocyte and monocyte CD11b expression during plasma separation is dependent on complement factor 5 (C5) - an ex vivo study with blood from a C5-deficient individual.

PubMed

Hardersen, Randolf; Enebakk, Terje; Christiansen, Dorte; Bergseth, Grethe; Brekke, Ole-Lars; Mollnes, Tom Eirik; Lappegård, Knut Tore; Hovland, Anders

2018-04-01

The aim of the study was to investigate the role of complement factor 5 (C5) in reactions elicited by plasma separation using blood from a C5-deficient (C5D) individual, comparing it to C5-deficient blood reconstituted with C5 (C5DR) and blood from healthy donors. Blood was circulated through an ex vivo plasma separation model. Leukocyte CD11b expression and leukocyte-platelet conjugates were measured by flow cytometry during a 30-min period. Other markers were assessed during a 240-min period. Granulocyte and monocyte CD11b expression did not increase in C5D blood during plasma separation. In C5DR samples granulocytes CD11b expression, measured by mean fluorescence intensity (MFI), increased from 10481 ± 6022 (SD) to 62703 ± 4936, and monocytes CD11b expression changed from 13837 ± 7047 to 40063 ± 713. Granulocyte-platelet conjugates showed a 2.5-fold increase in the C5DR sample compared to the C5D sample. Monocyte-platelet conjugates increased independently of C5. In the C5D samples, platelet count decreased from 210 × 10 9 /L (201-219) (median and range) to 51 × 10 9 /L (50-51), and C3bc increased from 14 CAU/mL (21-7) to 198 CAU/mL (127-269), whereas TCC formation was blocked during plasma separation. In conclusion, up-regulation of granulocyte and monocyte CD11b during plasma separation was C5-dependent. The results also indicate C5 dependency in granulocyte-platelet conjugates formation. © 2018 APMIS. Published by John Wiley & Sons Ltd.

Resonance energy transfer process in nanogap-based dual-color random lasing

NASA Astrophysics Data System (ADS)

Shi, Xiaoyu; Tong, Junhua; Liu, Dahe; Wang, Zhaona

2017-04-01

The resonance energy transfer (RET) process between Rhodamine 6G and oxazine in the nanogap-based random systems is systematically studied by revealing the variations and fluctuations of RET coefficients with pump power density. Three working regions stable fluorescence, dynamic laser, and stable laser are thus demonstrated in the dual-color random systems. The stable RET coefficients in fluorescence and lasing regions are generally different and greatly dependent on the donor concentration and the donor-acceptor ratio. These results may provide a way to reveal the energy distribution regulars in the random system and to design the tunable multi-color coherent random lasers for colorful imaging.

Long-term increases in lymphocytes and platelets in human T-lymphotropic virus type II infection

PubMed Central

Bartman, Melissa T.; Kaidarova, Zhanna; Hirschkorn, Dale; Sacher, Ronald A.; Fridey, Joy; Garratty, George; Gibble, Joan; Smith, James W.; Newman, Bruce; Yeo, Anthony E.

2008-01-01

Human T-lymphotropic viruses types I and II (HTLV-I and HTLV-II) cause chronic infections of T lymphocytes that may lead to leukemia and myelopathy. However, their long-term effects on blood counts and hematopoiesis are poorly understood. We followed 151 HTLV-I–seropositive, 387 HTLV-II–seropositive, and 799 HTLV-seronegative former blood donors from 5 U.S. blood centers for a median of 14.0 years. Complete blood counts were performed every 2 years. Multivariable repeated measures analyses were conducted to evaluate the independent effect of HTLV infection and potential confounders on 9 hematologic measurements. Participants with HTLV-II had significant (P < .05) increases in their adjusted lymphocyte counts (+126 cells/mm3; approximately +7%), hemoglobin (+2 g/L [+0.2 g/dL]) and mean corpuscular volume (MCV; 1.0 fL) compared with seronegative participants. Participants with HTLV-I and HTLV-II had higher adjusted platelet counts (+16 544 and +21 657 cells/mm3; P < .05) than seronegatives. Among all participants, time led to decreases in platelet count and lymphocyte counts, and to increases in MCV and monocytes. Sex, race, smoking, and alcohol consumption all had significant effects on blood counts. The HTLV-II effect on lymphocytes is novel and may be related to viral transactivation or immune response. HTLV-I and HTLV-II associations with higher platelet counts suggest viral effects on hematopoietic growth factors or cytokines. PMID:18755983

Platelet-rich plasma reduces skin flap inflammatory cells infiltration and improves survival rates through induction of angiogenesis: An experiment in rabbits.

PubMed

Wang, Biao; Geng, Qiuhua; Hu, Junling; Shao, Jianchuan; Ruan, Jing; Zheng, Jiansheng

2016-08-01

This study was conducted to evaluate the effects of platelet-rich plasma (PRP) on flap survival in an experimental rabbit model. Symmetrical rectangular dorsal cutaneous flaps (8 × 2 cm) were elevated in 15 rabbits. The rabbits were randomly divided into a 3-day group (n = 5), a 7-day group (n = 5), and a 14-day group (n = 5). Either side of the dorsum was selected for injection of PRP into the flap basal surface, while the other side received an equal volume of saline as a control. The flaps were immediately sutured back, after which the flap survival was measured and histology specimens were collected at 3, 7, and 14 days. Platelet-rich plasma significantly improved flap survival rates of the PRP side flaps relative to the control in the 3-day (74.4% ± 4.7% vs 65.8% ± 6.8%; p < 0.05), 7-day (72.4% ± 7.5% vs 58.5% ± 7.0%; p < 0.05), and 14-day (74.5% ± 5.0% vs 65.0% ± 5.4%; p < 0.05) groups. Histological analysis revealed significantly fewer inflammatory cells and an increased blood vessel density in the platelet-rich plasma side flap vs the blank control side flap. Platelet-rich plasma (PRP) promotes the survival of random rabbit flaps and, therefore, represents a promising treatment to prevent skin flap necrosis in reconstructive and plastic surgery.

Comparison of original and generic clopidogrel 600 mg loading dose in the patients who planned undergoing coronary angiography.

PubMed

Srimahachota, Suphot; Rojnuckarin, Ponlapat; Udayachalerm, Wasan; Buddhari, Wacin; Chaipromprasit, Jarkarpun; Lertsuwunseri, Vorarit; Akkawat, Benjaporn; Jirapattrathamrong, Somboon

2012-12-01

To compare the efficacy and safety of original (Plavix) and generic (Apolets) clopidogrel 600 mg loading in patients planning to undergo coronary angiography. This is an experimental design, parallel, randomized-controlled study. Coronary artery disease patients planned for cardiac catheterization were recruited Patients were randomized to receive either original or generic clopidogrel 600 mg loading dose. Platelet aggregation induced by 5 micromol/L and 20 micromol/L adenosine diphosphate (ADP) was measured by light transmission aggregometry (LTA) at baseline and 6 hours after clopidogrel 600 mg administration. Forty-nine patients were enrolled, 24 patients received original clopidogrel, and 25 patients received generic clopidogrel. After six hours of loading, there was significantly reduction in platelet aggregation induced by adenosine 5 micromol/L from 41.08 +/- 3.04% to 19.50 +/- 1.68% (p < 0.001) in original group compared to 36.76 +/- 2.66% to 21.32 +/- 2.60% (p < 0.001) in generic group. When induced by 20 micromol/L, the platelet aggregation was reduced from 58.50 +/- 2.09% to 32.25 +/- 2.30% (p < 0.001) in original group and from 61.12 +/- 2.54% to 30.04 +/- 3.14% (p < 0.001) in generic group. There was no significant difference between original and generic clopidogrel in reducing platelet aggregation induced by both adenosine 5 and 20 micromol/L. Groin hematoma was found in one case (4.2%) in the original clopidogrel group. Generic clopidogrel (Apolets) 600 mg loading dose is as effective as original clopidogrel (Plavix) in term of platelet aggregation inhibition.

Pain in donor site after BTB-ACL reconstruction with PRGF: a randomized trial.

PubMed

Seijas, Roberto; Cuscó, Xavier; Sallent, Andrea; Serra, Iván; Ares, Oscar; Cugat, Ramón

2016-06-01

Anterior cruciate ligament (ACL) tears are highly incident injuries in young athletes within our work area. The use of the patellar graft, despite being the treatment of choice, presents post-operative problems such as anterior knee pain, which limits its use and leads to preference being taken for alternative grafts. Our aim was to evaluate if the application of PRGF reduces anterior knee pain in donor site in BTB-ACL reconstruction. 43 patients were included in the double-blinded and randomized clinical trial comparing two patient groups who underwent ACL reconstruction using patellar tendon graft, comparing anterior knee pain with and without the application of PRGF at the donor site after harvesting the graft. The PRGF group showed decreased donor site pain in comparison to the control group, with significant differences in the first two months of follow-up. The application of PRGF decreased donor site pain compared to the control group.

Computational reconstruction and fluid dynamics of in vivo thrombi from the microcirculation

NASA Astrophysics Data System (ADS)

Mirramezani, Mehran; Tomaiuolo, Maurizio; Stalker, Timothy; Shadden, Shawn

2016-11-01

Blood flow and mass transfer can have significant effects on clot growth, composition and stability during the hemostatic response. We integrate in vivo data with CFD to better understand transport processes during clot formation. By utilizing electron microscopy, we reconstructed the 3D thrombus structure formed after a penetrating laser injury in a mouse cremaster muscle. Random jammed packing is used to reconstruct the microenvironment of the platelet aggregate, with platelets modeled as ellipsoids. In our 3D model, Stokes flow is simulated to obtain the velocity field in the explicitly meshed gaps between platelets and the lumen surrounding the thrombus. Based on in vivo data, a clot is composed of a core of highly activated platelets covered by a shell of loosely adherent platelets. We studied the effects of clot size (thrombus growth), gap distribution (consolidation), and vessel blood flow rate on mean intrathrombus velocity. The results show that velocity is smaller in the core as compared to the shell, potentially enabling higher concentration of agonists in the core contributing to its activation. In addition, our results do not appear to be sensitive to the geometry of the platelets, but rather gap size plays more important role on intrathrombus velocity and transport.

[Detection of hepatitis c in blood donors in Niamey].

PubMed

Mamadou, S; Gragnic, G; Kabo, R; Salami, H; Boulkassoum, Z

1997-01-01

We searched for HCV antibodies in a random sample of 410 blood donors negative for HIV infection, hepatitis B and syphilis. 16 peoples were positive by ELISA and 13 by RIBA. So 3.2% of these donors negative for the three actual compulsory tests, are able to transmit HCV.

Meal-induced platelet activation in Type 2 diabetes mellitus: effects of treatment with repaglinide and glibenclamide.

PubMed

Yngen, M; Ostenson, C-G; Hjemdahl, P; Wallén, N H

2006-02-01

To compare the effects of treatment with repaglinide and glibenclamide on platelet function and endothelial markers in patients with Type 2 diabetes mellitus, before and after a standardized meal. Fifteen patients with Type 2 diabetes were investigated on three occasions: at baseline without oral hypoglycaemic drug treatment, and after 6 weeks' treatment with repaglinide or glibenclamide, respectively, in an open randomized cross-over study. Agonist-induced platelet P-selectin expression and platelet aggregation, urinary thromboxane, soluble P-selectin, von Willebrand factor (VWF), soluble E-selectin, intercellular adhesion molecule (ICAM-1) and C-reactive protein (CRP) were measured. In addition, pre-meal data were compared with non-diabetic control subjects (n = 15), matched for sex, age and BMI. Adenosine diphosphate (ADP)-induced platelet P-selectin expression increased post-meal in Type 2 diabetic patients both at baseline and after treatment with repaglinide and glibenclamide (P < 0.01 for all; repeated measures anova). Repaglinide treatment reduced fasting ADP-induced P-selectin expression compared with baseline (P = 0.01), but did not influence meal-induced platelet hyper-reactivity (P = 0.32). No significant anti-platelet effects of glibenclamide treatment were found. Plasma concentrations of VWF and ICAM-1 were elevated in patients with Type 2 diabetes compared with control subjects (P < 0.05 for both) and were reduced during treatment with repaglinide (P < 0.01 for both) but did not change during glibenclamide treatment. The post-meal state is associated with enhanced platelet reactivity in patients with Type 2 diabetes mellitus. Pre-meal treatment with repaglinide or glibenclamide does not inhibit postprandial platelet activation, but repaglinide treatment is associated with attenuated platelet and endothelial activity in the fasting state.

Effects of aspirin, carprofen, deracoxib, and meloxicam on platelet function and systemic prostaglandin concentrations in healthy dogs.

PubMed

Blois, Shauna L; Allen, Dana G; Wood, R Darren; Conlon, Peter D

2010-03-01

To determine effects of therapeutic dosages of aspirin, carprofen, deracoxib, and meloxicam on platelet function and systemic prostaglandin concentrations in healthy dogs. 10 hound-crossbred dogs. Aspirin (10 mg/kg, PO, q 12 h), carprofen (4.4 mg/kg, PO, q 24 h), deracoxib (2 mg/kg, PO, q 24 h), meloxicam (0.1 mg/kg, PO, q 24 h), and a placebo were administered for 7 days in a random order to each of 10 healthy dogs; there was a 21-day washout period between subsequent treatments. One-stage prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration, and plasma concentrations of thromboxane (TX)B(2) and 6-keto prostaglandin (PG)F(1alpha) were measured before and after treatment administration. Platelet function was assessed by use of a platelet-function analyzer and aggregation. Aspirin, carprofen, and meloxicam did not significantly affect platelet function. Deracoxib caused a mild decrease in platelet aggregation induced by 50microM ADP. Platelet number, Hct, PT, aPTT, and plasma TXB(2) and 6-keto PGF(1alpha) concentrations were unchanged after NSAID administration. Meloxicam administration resulted in a significant decrease in fibrinogen concentration, but results remained within the laboratory reference interval. Oral administration of commonly used NSAIDs at therapeutic dosages in healthy dogs did not alter plasma TXB(2) and 6-keto PGF(1alpha) concentrations. Deracoxib administration resulted in a minor abnormality in platelet aggregation. Anti-inflammatory doses of aspirin did not affect platelet function as measured by use of optical aggregometry and a platelet-function analyzer. Further evaluation of the effects of aspirin and cyclooxygenase-2-selective inhibitors on hemostasis should be performed.

Platelet rich plasma for the management of hair loss: Better alone or in combination?

PubMed

Anitua, Eduardo; Pino, Ander; Jaén, Pedro; Navarro, Mª Rogelia

2018-06-14

Platelet-rich plasma (PRP) and autologous protein-based treatments have recently emerged as a potential therapeutic approach for hair loss-related disorders including androgenetic alopecia and alopecia areata. The safety and efficacy of repeated intradermal injections of PRP has proved to promote hair growth in a number of randomized clinical trials. Biologically active proteins and cytokines released upon platelet activation have shown to induce folliculogenesis and activate the anagen growing phase of dormant bulbs. Interestingly, further studies have revealed that combining PRP with other hair loss-related products may enhance the final performance of the treatment. These synergistic approaches include Food and Drug Administration (FDA) approved drugs such as finasteride or minoxidil, bioactive macromolecules and cell-based therapies. Here, recent research involving alone or combined therapy with platelet-rich plasma for the management of hair loss-related disorders are outlined and future prospects are discussed. © 2018 Wiley Periodicals, Inc.

Concomitant nitrates enhance clopidogrel response during dual anti-platelet therapy.

PubMed

Lee, Dong Hyun; Kim, Moo Hyun; Guo, Long Zhe; De Jin, Cai; Cho, Young Rak; Park, Kyungil; Park, Jong Sung; Park, Tae-Ho; Serebruany, Victor

2016-01-15

Despite advances in modern anti-platelet strategies, clopidogrel still remains the cornerstone of dual anti-platelet therapy (DAPT) in patients undergoing percutaneous coronary interventions (PCI). There is some inconclusive evidence that response after clopidogrel may be impacted by concomitant medications, potentially affecting clinical outcomes. Sustained released nitrates (SRN) are commonly used together with clopidogrel in post-PCI setting for mild vasodilatation and nitric oxide-induced platelet inhibition. We prospectively enrolled 458 patients (64.5 ± 9.6 years old, and 73.4% males) following PCI undergoing DAPT with clopidogrel and aspirin. Platelet reactivity was assessed by the VerifyNow™ P2Y12 assay at the maintenance outpatient setting. Concomitant SRN (n=266) significantly (p=0.008) enhanced platelet inhibition after DAPT (251.6 ± 80.9PRU) when compared (232.1 ± 73.5PRU) to the SRN-free (n=192) patients. Multivariate logistic regression analysis with the cut-off value of 253 PRU for defining heightened platelet reactivity confirmed independent correlation of more potent platelet inhibition during DAPT and use of SRN (Relative risk=1.675; Odds ratio [1.059-2.648]; p=0.027). In contrast, statins, calcium-channel blockers, beta blockers, angiotensin receptor blockers, ACE-inhibitors, diuretics, and anti-diabetic agents did not significantly impact platelet inhibition following DAPT. The synergic ability of SRN to enhance response during DAPT may have important clinical implications with regard to better cardiovascular protection, but extra bleeding risks, requiring further confirmation in a large randomized study. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

pH value promotes growth of Staphylococcus epidermidis in platelet concentrates.

PubMed

Störmer, Melanie; Kleesiek, Knut; Dreier, Jens

2008-05-01

The platelet (PLT) storage lesion is characterized metabolically by a pH value associated with lactic acid generation. PLT storage conditions support the growth of Staphylococcus epidermidis, the most common organism implicated in bacterial contamination of PLT concentrates (PCs). Here, different factors that influence bacterial growth in PCs are discussed and the relation between pH values of PCs and citrate plasma (CP) is studied, with emphasis on bacterial proliferation. The PLT lesion with regard to pH decrease and lactic acid production was monitored during storage and correlated to bacterial proliferation properties. A total of 115 coagulase-negative staphylococci, especially S. epidermidis isolates, were characterized for their proliferation in different blood components (CP, buffy coat-derived, and apheresis PCs). Furthermore, the influence of donor-specific, product-specific, species-specific, and strain-specific factors on bacterial proliferation was investigated. PCs showed a lower pH value in comparison to plasma during storage. Bacterial proliferation in PCs and the failure to grow in CP were determined with all organisms tested. No correlation to donor-specific, species-specific, or strain-specific factors was observed. Lowering the pH of CP resulted in bacterial proliferation, whereas a pH increase in the PC unit inhibited the proliferation of S. epidermidis. With emphasis on bacterial proliferation, the significant difference between PC and CP is the presence of metabolizing PLTs. The pH values of stored PLTs, but not those of stored plasma, support the growth of S. epidermidis.

Calcium supplementation during pregnancy for preventing hypertensive disorders is not associated with changes in platelet count, urate, and urinary protein: a randomized control trial.

PubMed

Hofmeyr, G J; Mlokoti, Z; Nikodem, V C; Mangesi, L; Ferreira, S; Singata, M; Jafta, Z; Merialdi, M; Hazelden, C; Villar, J

2008-01-01

To test the hypothesis that calcium supplementation inhibits the underlying pathological processes in women with preeclampsia. Seven hundred and eight nulliparous women were enrolled in a WHO randomized double-blind trial, who received 1.5 g of calcium or placebo from 20 weeks of pregnancy or earlier. Platelet count, serum urate, and urinary protein/creatinine ratio were measured at or near 35 gestational weeks. No difference was detected in rates of abnormal platelet count (relative risk [RR] 1.18; 95% confidence interval [CI], 0.63 to 2.18), serum urate level (1.0; 0.64 to 1.57) or urine protein/creatinine ratio (1.01; 0.76 to 1.34). This was consistent with the main trial finding of no difference in the incidence of 'dipstick' proteinuria between women receiving calcium and those receiving placebo (8312 women; RR, 1.01; 95% CI, 0.88 to 1.15). An effect of calcium supplementation in the second half of pregnancy on the rate of abnormal laboratory measures associated with preeclampsia was not demonstrated.

A randomized trial to evaluate the use of text messaging, letter and telephone call reminders to improve return of blood donors with reactive serologic tests

PubMed Central

Porto-Ferreira, Francisco Augusto; de Almeida-Neto, Cesar; Murphy, Edward L.; de Camargo Montebello, Sandra; Nogueira, Fátima Aparecida Hangai; Koga da Silva, Edina Mariko; MacFarland, William; Custer, Brian

2016-01-01

Introduction Low return rates for notification and counseling among donors with reactive serologic screening tests have been reported worldwide. A randomized trial to test the effectiveness of text message, letter or telephone call reminders to improve return among non-responding first-time blood donors with reactive serologic tests was conducted. Methods Donors with serologically reactive screening test results who had a cell phone and resided in the metropolitan telephone area code of São Paulo in the period from August 2013 through July 2014 were eligible. A consecutive sample of first-time donors with reactive screening tests who had not responded to a standard letter requesting the donor return to the blood center were randomly assigned to receive a text, a new letter or a telephone call requesting return for notification and counseling. Return rates were measured over the subsequent 30 days. Results Return following a phone call reminder was better than a text message (39.8% vs. 28.4%; OR=1.66; 95%CI 1.05–2.64) but not better than a letter (39.8% vs. 34.4%; OR=1.32; 95%CI 0.83–2.12). Older age was a predictor of higher rate of return with each year increase in age associated with a 2% increase in the odds of return (OR=1.02; 95%CI 1.01–1.04). Conclusion In non-responding serologic reactive donors, telephone call led to a higher return rate than text message. The results of this study suggest that use of text messages, while attractive for its simplicity, will not lead to increased donor notification success following serologically reactive marker results from blood donation in Brazil. PMID:27774609

Mesoscale properties of clay aggregates from potential of mean force representation of interactions between nanoplatelets

NASA Astrophysics Data System (ADS)

Ebrahimi, Davoud; Whittle, Andrew J.; Pellenq, Roland J.-M.

2014-04-01

Face-to-face and edge-to-edge free energy interactions of Wyoming Na-montmorillonite platelets were studied by calculating potential of mean force along their center to center reaction coordinate using explicit solvent (i.e., water) molecular dynamics and free energy perturbation methods. Using a series of configurations, the Gay-Berne potential was parametrized and used to examine the meso-scale aggregation and properties of platelets that are initially random oriented under isothermal-isobaric conditions. Aggregates of clay were defined by geometrical analysis of face-to-face proximity of platelets with size distribution described by a log-normal function. The isotropy of the microstructure was assessed by computing a scalar order parameter. The number of platelets per aggregate and anisotropy of the microstructure both increases with platelet plan area. The system becomes more ordered and aggregate size increases with increasing pressure until maximum ordered state at confining pressure of 50 atm. Further increase of pressure slides platelets relative to each other leading to smaller aggregate size. The results show aggregate size of (3-8) platelets for sodium-smectite in agreement with experiments (3-10). The geometrical arrangement of aggregates affects mechanical properties of the system. The elastic properties of the meso-scale aggregate assembly are reported and compared with nanoindentation experiments. It is found that the elastic properties at this scale are close to the cubic systems. The elastic stiffness and anisotropy of the assembly increases with the size of the platelets and the level of external pressure.

[Hemogram profile and interest of pre-donation hemoglobin measurement in blood donors in the northwest region of Morocco].

PubMed

Bakrim, S; Ouarour, A; Jaidann, K; Benajiba, M; Masrar, A

2018-02-01

Blood donation in Morocco and more particularly in the northwest region is carried out without prior determination of the pre-donation hemoglobin. In addition, we note the lack of scientific research that reports data on the red blood cells, leukocytes and platelet lines in donated blood at the regional or even national level. To study hemogram profile in blood donors taken from the Northwest region of Morocco in order to provide decision makers of the National Center of Blood Transfusion and Hematology with valid scientific arguments to complete the criteria to donate whole blood, by the hemogram. Prospective study, conducted in 15797 volunteer blood donors (BD) aged between 18 and 60 years, collected during mobile or fixed collections carried out by the Regional Blood Transfusion Center of Tangier and Tetouan from November 2014 to May 2016. The hemogram was performed using a Sysmex KX21N ® and the analysis of the data was done by the software SPSS 20.0. According to the World Health Organization, anemia corresponds to a hemoglobin level less than 12g/dL in women and less than 13g/dL in men. We found that 14.5 % of women (n=1054) and 3.0 % of men (n=245) were anemic and anemia was hypochromic microcytic in 58,66 % of these BD. Analysis of the white line showed leucopenia in 2.05 % of BD and 807 cases of leukocytosis (5.27 % of BD). Platelet study showed thrombocytopenia in 3.97 % of BD and thrombocytosis in 151BD (0.99 % of cases). This study shows the interest of systematic pre-donation hemoglobin measurement and periodic realization of the hemogram among BD in the Northwest region of Morocco. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Prospective, randomized, blinded evaluation of donor semen quality provided by seven commercial sperm banks.

PubMed

Carrell, Douglas T; Cartmill, Deborah; Jones, Kirtly P; Hatasaka, Harry H; Peterson, C Matthew

2002-07-01

To evaluate variability in donor semen quality between seven commercial donor sperm banks, within sperm banks, and between intracervical insemination and intrauterine insemination. Prospective, randomized, blind evaluation of commercially available donor semen samples. An academic andrology laboratory. Seventy-five cryopreserved donor semen samples were evaluated. Samples were coded, then blindly evaluated for semen quality. Standard semen quality parameters, including concentration, motility parameters, World Health Organization criteria morphology, and strict criteria morphology. Significant differences were observed between donor semen banks for most semen quality parameters analyzed in intracervical insemination samples. In general, the greatest variability observed between banks was in percentage progressive sperm motility (range, 8.8 +/- 5.8 to 42.4 +/- 5.5) and normal sperm morphology (strict criteria; range, 10.1 +/- 3.3 to 26.6 +/- 4.7). Coefficients of variation within sperm banks were generally high. These data demonstrate the variability of donor semen quality provided by commercial sperm banks, both between banks and within a given bank. No relationship was observed between the size or type of sperm bank and the degree of variability. The data demonstrate the lack of uniformity in the criteria used to screen potential semen donors and emphasize the need for more stringent screening criteria and strict quality control in processing samples.

Polymer surfaces structured with random or aligned electrospun nanofibers to promote the adhesion of blood platelets.

PubMed

Wan, Ling-Shu; Xu, Zhi-Kang

2009-04-01

Fibrous membranes (nonwoven meshes) prepared via electrospinning technique have great potential in tissue engineering. This work is the first study on the behaviors of blood platelets at the nanostructured surface generated by electrospinning. Poly[acrylonitrile-co-(N-vinyl-2-pyrrolidone)] (PANCNVP) that shows excellent antiplatelet adhesion ability was directly electrospun onto its dense membrane surface. Polyacrylonitrile (PAN) samples were used as controls. The depth as well as the density of the nanofibers can be easily controlled. The results showed that the PANCNVP dense membrane certainly suppressed the activation and adhesion of platelets. However, whether the nanofibers and underlying membranes were composed of PAN or PANCNVP, the nanostructured surfaces promoted the activation, adhesion, and orientation of platelets. It was also found that, if the space between fibers was too large or the depth of fibers was too small, the nanostructured surface did not change the property of antiplatelet adhesion of PANCNVP. The promotion of activation and adhesion of platelets was obviously due to the presence of nanofibers, which induced the changes of surface topography and charge. Copyright 2008 Wiley Periodicals, Inc.

Broadband and polarization reflectors in the lookdown, Selene vomer

PubMed Central

Zhao, Shulei; Brady, Parrish Clawson; Gao, Meng; Etheredge, Robert Ian; Kattawar, George W.; Cummings, Molly E.

2015-01-01

Predator evasion in the open ocean is difficult because there are no objects to hide behind. The silvery surface of fish plays an important role in open water camouflage. Various models have been proposed to account for the broadband reflectance by the fish skin that involve one-dimensional variations in the arrangement of guanine crystal reflectors, yet the three-dimensional organization of these guanine platelets have not been well characterized. Here, we report the three-dimensional organization and the optical properties of integumentary guanine platelets in a silvery marine fish, the lookdown (Selene vomer). Our structural analysis and computational modelling show that stacks of guanine platelets with random yaw angles in the fish skin produce broadband reflectance via colour mixing. Optical axes of the guanine platelets and the collagen layer are aligned closely and provide bulk birefringence properties that influence the polarization reflectance by the skin. These data demonstrate how the lookdown preserves or alters polarization states at different incident polarization angles. These optical properties resulted from the organization of these guanine platelets and the collagen layer may have implications for open ocean camouflage in varying light fields. PMID:25673301

Carica papaya Leaves Juice Significantly Accelerates the Rate of Increase in Platelet Count among Patients with Dengue Fever and Dengue Haemorrhagic Fever

PubMed Central

Subenthiran, Soobitha; Choon, Tan Chwee; Cheong, Kee Chee; Thayan, Ravindran; Teck, Mok Boon; Muniandy, Prem Kumar; Afzan, Adlin; Abdullah, Noor Rain; Ismail, Zakiah

2013-01-01

The study was conducted to investigate the platelet increasing property of Carica papaya leaves juice (CPLJ) in patients with dengue fever (DF). An open labeled randomized controlled trial was carried out on 228 patients with DF and dengue haemorrhagic fever (DHF). Approximately half the patients received the juice, for 3 consecutive days while the others remained as controls and received the standard management. Their full blood count was monitored 8 hours for 48 hours. Gene expression studies were conducted on the ALOX 12 and PTAFR genes. The mean increase in platelet counts were compared in both groups using repeated measure ANCOVA. There was a significant increase in mean platelet count observed in the intervention group (P < 0.001) but not in the control group 40 hours since the first dose of CPLJ. Comparison of mean platelet count between intervention and control group showed that mean platelet count in intervention group was significantly higher than control group after 40 and 48 hours of admission (P < 0.01). The ALOX 12 (FC  =  15.00) and PTAFR (FC  =  13.42) genes were highly expressed among those on the juice. It was concluded that CPLJ does significantly increase the platelet count in patients with DF and DHF. PMID:23662145

Comparison between the effects of platelet-rich plasma and bone marrow concentrate on defect consolidation in the rabbit tibia

PubMed Central

Batista, Marco Antonio; Leivas, Tomaz Puga; Rodrigues, Consuelo Junqueira; Arenas, Géssica Cantadori Funes; Belitardo, Donizeti Rodrigues; Guarniero, Roberto

2011-01-01

OBJECTIVE: To perform a comparative analysis of the effects of platelet-rich plasma and centrifuged bone marrow aspirate on the induction of bone healing in rabbits. METHOD: Twenty adult, male New Zealand rabbits were randomly separated into two equal groups, and surgery was performed to create a bone defect (a cortical orifice 3.3 mm in diameter) in the proximal metaphysis of each rabbit's right tibia. In the first group, platelet-rich plasma was implanted in combination with β-tricalcium phosphate (platelet-rich plasma group), and in the second group, centrifuged bone marrow in combination with β-tricalcium phosphate (centrifuged bone marrow group) was implanted. After a period of four weeks, the animals were euthanized, and the tibias were evaluated using digital radiography, computed tomography, and histomorphometry. RESULTS: Seven samples from each group were evaluated. The radiographic evaluation confirmed the absence of fractures in the postoperative limb and identified whether bone consolidation had occurred. The tomographic evaluation revealed a greater amount of consolidation and the formation of a greater cortical bone thickness in the platelet-rich plasma group. The histomorphometry revealed a greater bone density in the platelet-rich plasma group compared with the centrifuged bone marrow group. CONCLUSION: After four weeks, the platelet-rich plasma promoted a greater amount of bone consolidation than the bone marrow aspirate concentrate. PMID:22012052

On-treatment platelet reactivity: State of the art and perspectives.

PubMed

Marcucci, Rossella; Grifoni, Elisa; Giusti, Betti

2016-02-01

High on-clopidogrel platelet reactivity (HcPR) during dual-antiplatelet therapy is a marker of vascular risk, in particular stent thrombosis, in patients with acute coronary syndromes (ACS). Genetic determinants (CYP2C19*2 polymorphism), advanced age, female gender, diabetes and reduced ventricular function are related to a higher risk to develop HcPR. In addition, inflammation and increased platelet turnover, as revealed by the elevated percentage of reticulated platelets in patients' blood, that characterize the acute phase of acute coronary syndromes, are associated with HcPR. To overcome the limitation of clopidogrel, new antiplatelet agents (prasugrel and ticagrelor) were developed and the demonstration of their superiority over clopidogrel was obtained in the two randomized trials, TRITON TIMI 38 and PLATO. Emerging evidence is accumulating on the role of high-on aspirin platelet reactivity (HaPR), especially in the clinical context of diabetes. Finally, the presence of new, potent antiplatelet drugs has shifted the focus from thrombotic to bleeding risk. Recent data document that low on-treatment platelet reactivity (LPR) is associated with a significantly higher bleeding risk. Due to the current possibility to choose between multiple antiplatelet strategies, the future perspective is to include in the management of ACS, in addition to clinical data and classical risk factors, the definition of platelet function during treatment in order to set a tailored therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of N-Acetylcysteine Pretreatment of Deceased Organ Donors on Renal Allograft Function: A Randomized Controlled Trial

PubMed Central

Orban, Jean-Christophe; Quintard, Hervé; Cassuto, Elisabeth; Jambou, Patrick; Samat-Long, Corine; Ichai, Carole

2015-01-01

Background Antioxidant donor pretreatment is one of the pharmacologic strategy proposed to prevent renal ischemia-reperfusion injuries and delayed graft function (DGF). The aim of the study was to investigate whether a donor pretreatment with N-acetylcysteine (NAC) reduces the incidence of DGF in adult human kidney transplant recipients. Methods In this randomized, open-label, monocenter trial, 160 deceased heart-beating donors were allowed to perform 236 renal transplantations from September 2005 to December 2010. Donors were randomized to receive, in a single-blind controlled fashion, 600 mg of intravenous NAC 1 hr before and 2 hr after cerebral angiography performed to confirm brain death. Primary endpoint was DGF defined by the need for at least one dialysis session within the first week or a serum creatinine level greater than 200 μmol/L at day 7 after kidney transplantation. Results The incidence of DGF was similar between donors pretreated with or without NAC (39/118; 33% vs. 30/118; 25.4%; P = 0.19). Requirement for at least one dialysis session was not different between the NAC and No NAC groups (17/118; 14.4% vs. 14/118; 11.8%, P = 0.56). The two groups had comparable serum creatinine levels, estimated glomerular filtration rates, and daily urine output at days 1, 7, 15, and 30 after kidney transplantation as well as at hospital discharge. No difference in recipient mortality nor in 1-year kidney graft survival was observed. Conclusion Donor pretreatment with NAC does not improve delayed graft function after kidney transplantation. PMID:25250647

Randomized controlled trial of docosahexaenoic acid supplementation in midwestern U.S. human milk donors.

PubMed

Valentine, Christina J; Morrow, Georgia; Pennell, Michael; Morrow, Ardythe L; Hodge, Amanda; Haban-Bartz, Annette; Collins, Kristin; Rogers, Lynette K

2013-02-01

Docosahexaenoic acid (DHA) is a long-chain polyunsaturated fatty acid important for neonatal neurodevelopment and immune homeostasis. Preterm infants fed donor milk from a Midwestern source receive only 20% of the intrauterine accretion of DHA. We tested the hypothesis that DHA supplementation of donor mothers would provide preterm infants with DHA intake equivalent to fetal accretion. After Institutional Review Board approval and informed consent, human milk donors to the Mother's Milk Bank of Ohio were randomized to receive 1 g of DHA (Martek(®) [now DSM Nutritional Lipids, Columbia, MD]) or placebo soy oil. Dietary intake data were collected and analyzed by a registered dietitian. Fatty acids were measured by gas chromatography/flame ionization detection. Statistical analysis used linear mixed models. Twenty-one mothers were randomly assigned to either the DHA group (n=10) or the placebo group (n=11). Donor age was a median of 31 years in both groups with a mean lactational stage of 19 weeks. Dietary intake of DHA at baseline in both groups was a median of 23 mg/day (range, 0-194 mg), significantly (p<0.0001) less than the minimum recommended intake of 200 mg/day. The DHA content of milk increased in the DHA-supplemented group (p<0.05). The women enrolled in this study had low dietary DHA intake. Supplementation with preformed DHA at 1 g/day resulted in increased DHA concentrations in the donor milk with no adverse outcomes. Infants fed donor milk from supplemented women receive dietary DHA levels that closely mimic normal intrauterine accretion during the third trimester.

Allele frequencies of human platelet antigens in Banjar, Bugis, Champa, Jawa and Kelantan Malays in Peninsular Malaysia.

PubMed

Wan Syafawati, W U; Norhalifah, H K; Zefarina, Z; Zafarina, Z; Panneerchelvam, S; Norazmi, M N; Chambers, G K; Edinur, H A

2015-10-01

The major aims of this study are to characterise and compile allelic data of human platelet antigen (HPA)-1 to -6 and -15 systems in five Malay sub-ethnic groups in Peninsular Malaysia. HPAs are polymorphic glycoproteins expressed on the surface of platelet membranes and are genetically differentiated across ethnogeographically unrelated populations. Blood samples were obtained with informed consent from 192 volunteers: Banjar (n = 30), Bugis (n = 37), Champa (n = 51), Jawa (n = 39) and Kelantan (n = 35). Genotyping was done using polymerase chain reaction-sequence specific primer method. In general, frequencies of HPAs in the Malay sub-ethnic groups are more similar to those in Asian populations compared with other more distinct populations such as Indians, Australian Aborigines and Europeans. This study provides the first HPA datasets for the selected Malay sub-ethnic groups. Subsequent analyses including previously reported HPA data of Malays, Chinese and Indians revealed details of the genetic relationships and ancestry of various sub-populations in Peninsular Malaysia. Furthermore, the comprehensive HPA allele frequency information from Peninsular Malaysia provided in this report has potential applications for future study of diseases, estimating risks associated with HPA alloimmunization and for developing an efficient HPA-typed donor recruitment strategy. © 2015 British Blood Transfusion Society.

Circulating Microparticles Alter Formation, Structure, and Properties of Fibrin Clots.

PubMed

Zubairova, Laily D; Nabiullina, Roza M; Nagaswami, Chandrasekaran; Zuev, Yuriy F; Mustafin, Ilshat G; Litvinov, Rustem I; Weisel, John W

2015-12-04

Despite the importance of circulating microparticles in haemostasis and thrombosis, there is limited evidence for potential causative effects of naturally produced cell-derived microparticles on fibrin clot formation and its properties. We studied the significance of blood microparticles for fibrin formation, structure, and susceptibility to fibrinolysis by removing them from platelet-free plasma using filtration. Clots made in platelet-free and microparticle-depleted plasma samples from the same healthy donors were analyzed in parallel. Microparticles accelerate fibrin polymerisation and support formation of more compact clots that resist internal and external fibrinolysis. These variations correlate with faster thrombin generation, suggesting thrombin-mediated kinetic effects of microparticles on fibrin formation, structure, and properties. In addition, clots formed in the presence of microparticles, unlike clots from the microparticle-depleted plasma, contain 0.1-0.5-μm size granular and CD61-positive material on fibres, suggesting that platelet-derived microparticles attach to fibrin. Therefore, the blood of healthy individuals contains functional microparticles at the levels that have a procoagulant potential. They affect the structure and stability of fibrin clots indirectly through acceleration of thrombin generation and through direct physical incorporation into the fibrin network. Both mechanisms underlie a potential role of microparticles in haemostasis and thrombosis as modulators of fibrin formation, structure, and resistance to fibrinolysis.

Circulating Microparticles Alter Formation, Structure, and Properties of Fibrin Clots

PubMed Central

Zubairova, Laily D.; Nabiullina, Roza M.; Nagaswami, Chandrasekaran; Zuev, Yuriy F.; Mustafin, Ilshat G.; Litvinov, Rustem I.; Weisel, John W.

2015-01-01

Despite the importance of circulating microparticles in haemostasis and thrombosis, there is limited evidence for potential causative effects of naturally produced cell-derived microparticles on fibrin clot formation and its properties. We studied the significance of blood microparticles for fibrin formation, structure, and susceptibility to fibrinolysis by removing them from platelet-free plasma using filtration. Clots made in platelet-free and microparticle-depleted plasma samples from the same healthy donors were analyzed in parallel. Microparticles accelerate fibrin polymerisation and support formation of more compact clots that resist internal and external fibrinolysis. These variations correlate with faster thrombin generation, suggesting thrombin-mediated kinetic effects of microparticles on fibrin formation, structure, and properties. In addition, clots formed in the presence of microparticles, unlike clots from the microparticle-depleted plasma, contain 0.1–0.5-μm size granular and CD61-positive material on fibres, suggesting that platelet-derived microparticles attach to fibrin. Therefore, the blood of healthy individuals contains functional microparticles at the levels that have a procoagulant potential. They affect the structure and stability of fibrin clots indirectly through acceleration of thrombin generation and through direct physical incorporation into the fibrin network. Both mechanisms underlie a potential role of microparticles in haemostasis and thrombosis as modulators of fibrin formation, structure, and resistance to fibrinolysis. PMID:26635081

Thrombin Generating Capacity and Phenotypic Association in ABO Blood Groups.

PubMed

Kremers, Romy M W; Mohamed, Abdulrahman B O; Pelkmans, Leonie; Hindawi, Salwa; Hemker, H Coenraad; de Laat, H Bas; Huskens, Dana; Al Dieri, Raed

2015-01-01

Individuals with blood group O have a higher bleeding risk than non-O blood groups. This could be explained by the lower levels of FVIII and von Willebrand Factor (VWF) levels in O individuals. We investigated the relationship between blood groups, thrombin generation (TG), prothrombin activation and thrombin inactivation. Plasma levels of VWF, FVIII, antithrombin, fibrinogen, prothrombin and α2Macroglobulin (α2M) levels were determined. TG was measured in platelet rich (PRP) and platelet poor plasma (PPP) of 217 healthy donors and prothrombin conversion and thrombin inactivation were calculated. VWF and FVIII levels were lower (75% and 78%) and α2M levels were higher (125%) in the O group. TG is 10% lower in the O group in PPP and PRP. Less prothrombin was converted in the O group (86%) and the thrombin decay capacity was lower as well. In the O group, α2M plays a significantly larger role in the inhibition of thrombin (126%). In conclusion, TG is lower in the O group due to lower prothrombin conversion, and a larger contribution of α2M to thrombin inactivation. The former is unrelated to platelet function because it is similar in PRP and PPP, but can be explained by the lower levels of FVIII.

Thrombin Generating Capacity and Phenotypic Association in ABO Blood Groups

PubMed Central

Hindawi, Salwa; Hemker, H. Coenraad; de Laat, H. Bas; Huskens, Dana; Al Dieri, Raed

2015-01-01

Individuals with blood group O have a higher bleeding risk than non-O blood groups. This could be explained by the lower levels of FVIII and von Willebrand Factor (VWF) levels in O individuals. We investigated the relationship between blood groups, thrombin generation (TG), prothrombin activation and thrombin inactivation. Plasma levels of VWF, FVIII, antithrombin, fibrinogen, prothrombin and α2Macroglobulin (α2M) levels were determined. TG was measured in platelet rich (PRP) and platelet poor plasma (PPP) of 217 healthy donors and prothrombin conversion and thrombin inactivation were calculated. VWF and FVIII levels were lower (75% and 78%) and α2M levels were higher (125%) in the O group. TG is 10% lower in the O group in PPP and PRP. Less prothrombin was converted in the O group (86%) and the thrombin decay capacity was lower as well. In the O group, α2M plays a significantly larger role in the inhibition of thrombin (126%). In conclusion, TG is lower in the O group due to lower prothrombin conversion, and a larger contribution of α2M to thrombin inactivation. The former is unrelated to platelet function because it is similar in PRP and PPP, but can be explained by the lower levels of FVIII. PMID:26509437

Platelet and endothelial activity in comorbid major depression and coronary artery disease patients treated with citalopram: the Canadian Cardiac Randomized Evaluation of Antidepressant and Psychotherapy Efficacy Trial (CREATE) biomarker sub-study.

PubMed

van Zyl, Louis T; Lespérance, Francois; Frasure-Smith, Nancy; Malinin, Alex I; Atar, Dan; Laliberté, Marc-André; Serebruany, Victor L

2009-01-01

Major depression is an independent risk factor for increased morbidity and mortality in patients with coronary artery disease (CAD). Increased platelet activity and vascular endothelial dysfunction are possible pathways through which depression may increase cardiovascular risk. Citalopram exhibits strong selective inhibition of human platelet activation, but little is known about its effects on vascular endothelium. We assessed whether treatment of depressed CAD patients with citalopram alters platelet/endothelial biomarkers. The study was performed within the framework of the CREATE trial. We assessed the effect of citalopram on P-selectin, beta-thromboglobulin (betaTG), soluble intercellular cell adhesion molecule-1 (sICAM-1), and total nitric oxide (tNO). Plasma samples were obtained at baseline and week 12 from subjects randomized to citalopram 20-40 mg daily (n = 36), or placebo (n = 21). Anticoagulants, aspirin, and clopidogrel were permitted. Treatment with citalopram was associated with greater increase in tNO over 12 weeks compared to placebo (P = 0.005). There were no differences for the other biomarkers such as P-selectin (P = 0.70), betaTG (P = 0.46) and ICAM (P = 0.59). Treatment with citalopram for 12 weeks in depressed CAD patients is associated with enhanced production of nitric oxide despite the co-administration of commonly prescribed anti-platelet regimens including aspirin and clopidogrel. Clinical implications of these findings are unclear, but improved endothelial function is implied by the increased NO production, suggesting that citalopram may be of particular benefit for patients with comorbid depression and vascular disease including CAD, stroke, peripheral artery disease, and diabetes.

[The impact of HLA haplotype and alleles mismatches of donor-recipient pairs on outcome of haploidentical hematopoietic stem cell transplantation with a third part cord blood unit].

PubMed

Zhu, W J; He, J; Bao, X J; Yuan, X N; Li, Y; Xue, S L; Pan, Z J; Chen, J; Wu, D P

2016-07-01

To analyze allele mismatches of HLA- A, - B, - C, - DRB1, - DQB1 and haplotype mismatch of donor- recipient pairs on the outcome of haploidentical transplantation combined with a third part cord blood unit. 230 pairs of donor-recipient were performed HLA-A, B, C, DRB1, DQB1 typing using SBT and SSOP methods from January 2012 to December 2014. Pairs were divided into HLA- 5/10、6/10、7/10 and ≥8/10 groups according to HLA- A, B, C and DRB1 highresolution typing and matched degrees, the 3-year probability of overall survival (OS) for each group were 48.7%, 59.3%, 71.1%, 38.3% (P=0.068) respectively. HLA-6/10 matched group associated with significant favorable effect on OS compared with HLA- 5/10 matched one (P=0.041).When the HLA class I antigen matched on the recipient and donor, improved OS and event free survival (EFS) in HLA- 6/10 matched group than in HLA-5/10 matched one (P=0.017,P=0.088), especially in single HLA-A loci allele matched one (P=0.013,P=0.013), were observed. As to the third part cord blood unit, sharing the same haplotype with the recipient-donor pairs produced better platelet recovery than the misfit one (95.3%vs 86.2%,P= 0.007), similar result was found in terms of neutrophil recovery (98.8%vs 96.1% ,P=0.022). HLA locus mismatch and haplotype mismatch of the donor and recipient should be useful for selection of the most optimum donor. Co- infused of an unrelated cord blood unit sharing the same haplotype with the recipient-donor pairs could improve hematopoietic recovery.

The "Aging Factor" Eotaxin-1 (CCL11) Is Detectable in Transfusion Blood Products and Increases with the Donor's Age.

PubMed

Hoefer, Julia; Luger, Markus; Dal-Pont, Christian; Culig, Zoran; Schennach, Harald; Jochberger, Stefan

2017-01-01

Background : High blood levels of the chemokine eotaxin-1 (CCL11) have recently been associated with aging and dementia, as well as impaired memory and learning in humans. Importantly, eotaxin-1 was shown to pass the blood-brain-barrier (BBB) and has been identified as crucial mediator of decreased neurogenesis and cognitive impairment in young mice after being surgically connected to the vessel system of old animals in a parabiosis model. It thus has to be assumed that differences in eotaxin-1 levels between blood donors and recipients might influence cognitive functions also in humans. However, it is unknown if eotaxin-1 is stable during processing and storage of transfusion blood components. This study assesses eotaxin-1 concentrations in fresh-frozen plasma (FFP), erythrocyte concentrate (EC), and platelet concentrate (PC) in dependence of storage time as well as the donor's age and gender. Methods : Eotaxin-1 was measured in FFP ( n = 168), EC ( n = 160) and PC ( n = 8) ready-to-use for transfusion employing a Q-Plex immunoassay for eotaxin-1. Absolute quantification of eotaxin-1 was performed with Q-view software. Results : Eotaxin-1 was consistently detected at a physiological level in FFP and EC but not PC. Eotaxin-1 levels were comparable in male and female donors but increased significantly with rising age of donors in both, FFP and EC. Furthermore, eotaxin-1 was not influenced by storage time of either blood component. Finally, eotaxin-1 is subject to only minor fluctuations within one donor over a longer period of time. Conclusion : Eotaxin-1 is detectable and stable in FFP and EC and increases with donor's age. Considering the presumed involvement in aging and cognitive malfunction, differences in donor- and recipient eotaxin-1 levels might affect mental factors after blood transfusion.

Thrombelastographic haemostatic status and antiplatelet therapy after coronary artery bypass surgery (TEG-CABG trial): assessing and monitoring the antithrombotic effect of clopidogrel and aspirin versus aspirin alone in hypercoagulable patients: study protocol for a randomized controlled trial.

PubMed

Rafiq, Sulman; Johansson, Pär Ingemar; Zacho, Mette; Stissing, Trine; Kofoed, Klaus; Lilleør, Nikolaj Bang; Steinbrüchel, Daniel Andreas

2012-04-27

Hypercoagulability, assessed by the thrombelastography (TEG) assay, has in several observational studies been associated with an increased risk of post-procedural thromboembolic complications. We hypothesize that intensified antiplatelet therapy with clopidogrel and aspirin, as compared to aspirin alone, will improve saphenous vein graft patency in preoperatively TEG-Hypercoagulable coronary artery bypass surgery (CABG) patients and reduce their risk for thromboembolic complications and death postoperatively. This is a prospective randomized clinical trial, with an open-label design with blinded evaluation of graft patency. TEG-Hypercoagulability is defined as a TEG maximum amplitude above 69 mm. Two hundred and fifty TEG-Hypercoagulable patients will be randomized to either an interventional group receiving clopidogrel 75 mg daily for three months (after initial oral bolus of 300 mg) together with aspirin 75 mg or a control group receiving aspirin 75 mg daily alone. Monitoring of antiplatelet efficacy and on-treatment platelet reactivity to clopidogrel and aspirin will be conducted with Multiplate aggregometry. Graft patency will be assessed with Multislice computed tomography (MSCT) at three months after surgery. The present trial is the first randomized clinical trial to evaluate whether TEG-Hypercoagulable CABG patients will benefit from intensified antiplatelet therapy after surgery. Monitoring of platelet inhibition from instituted antithrombotic therapy will elucidate platelet resistance patterns after CABG surgery. The results could be helpful in redefining how clinicians can evaluate patients preoperatively for their postoperative thromboembolic risk and tailor individualized postoperative antiplatelet therapy. Clinicaltrials.gov Identifier NCT01046942.

Dose of Prophylactic Platelet Transfusions and Prevention of Hemorrhage

PubMed Central

Slichter, Sherrill J.; Kaufman, Richard M.; Assmann, Susan F.; McCullough, Jeffrey; Triulzi, Darrell J.; Strauss, Ronald G.; Gernsheimer, Terry B.; Ness, Paul M.; Brecher, Mark E.; Josephson, Cassandra D.; Konkle, Barbara A.; Woodson, Robert D.; Ortel, Thomas L.; Hillyer, Christopher D.; Skerrett, Donna L.; McCrae, Keith R.; Sloan, Steven R.; Uhl, Lynne; George, James N.; Aquino, Victor M.; Manno, Catherine S.; McFarland, Janice G.; Hess, John R.; Leissinger, Cindy; Granger, Suzanne

2010-01-01

BACKGROUND We conducted a trial of prophylactic platelet transfusions to evaluate the effect of platelet dose on bleeding in patients with hypoproliferative thrombocytopenia. METHODS We randomly assigned hospitalized patients undergoing hematopoietic stem-cell transplantation or chemotherapy for hematologic cancers or solid tumors to receive prophylactic platelet transfusions at a low dose, a medium dose, or a high dose (1.1×1011, 2.2×1011, or 4.4×1011 platelets per square meter of body-surface area, respectively), when morning platelet counts were 10,000 per cubic millimeter or lower. Clinical signs of bleeding were assessed daily. The primary end point was bleeding of grade 2 or higher (as defined on the basis of World Health Organization criteria). RESULTS In the 1272 patients who received at least one platelet transfusion, the primary end point was observed in 71%, 69%, and 70% of the patients in the low-dose group, the medium-dose group, and the high-dose group, respectively (differences were not significant). The incidences of higher grades of bleeding, and other adverse events, were similar among the three groups. The median number of platelets transfused was significantly lower in the low-dose group (9.25×1011) than in the medium-dose group (11.25×1011) or the high-dose group (19.63×1011) (P = 0.002 for low vs. medium, P<0.001 for high vs. low and high vs. medium), but the median number of platelet transfusions given was significantly higher in the low-dose group (five, vs. three in the medium-dose and three in the high-dose group; P<0.001 for low vs. medium and low vs. high). Bleeding occurred on 25% of the study days on which morning platelet counts were 5000 per cubic millimeter or lower, as compared with 17% of study days on which platelet counts were 6000 to 80,000 per cubic millimeter (P<0.001). CONCLUSIONS Low doses of platelets administered as a prophylactic transfusion led to a decreased number of platelets transfused per patient but an increased number of transfusions given. At doses between 1.1×1011 and 4.4×1011 platelets per square meter, the number of platelets in the prophylactic transfusion had no effect on the incidence of bleeding. (ClinicalTrials.gov number, NCT00128713.) PMID:20164484

Coming safely to a stop: a review of platelet activity after cessation of antiplatelet drugs.

PubMed

Ford, Isobel

2015-08-01

The platelet P2Y12 antagonists are widely used, usually in combination with aspirin, to prevent atherothrombotic events in patients with acute coronary syndromes during percutaneous coronary intervention and after placement of arterial stents. Inhibition by clopidogrel or prasugrel lasts for the lifetime of the affected platelets and platelet haemostatic function gradually recovers after stopping the drug, as new unaffected platelets are formed. The optimal durations for dual antiplatelet therapy are prescribed by clinical guidelines. Continuation beyond the recommended duration is associated with an increased mortality, mainly associated with major bleeding. Fear of a 'rebound' of prothrombotic platelet activity on stopping the drug has provoked much discussion and many studies. However, review of the available literature reveals no evidence for production of hyper-reactive platelets after cessation of clopidogrel in patients who are stable. Any increase in acute coronary and other vascular events after stopping seems most likely therefore to be due to premature discontinuation or disruption of treatment while thrombotic risk is still high. No difference in rebound was found with the newer P2Y12 inhibitors, although ticagrelor and prasugrel are more potent platelet inhibitors than clopidogrel. Recent randomized controlled trials confirm it is safe to stop the thienopyridine and continue with aspirin alone in most patients after the duration of treatment recommended by the guidelines. Decisions on when to stop therapy in individuals, however, remain challenging and there is a growing rationale for platelet testing to assist clinical judgement in certain situations such as patients stopping dual antiplatelet therapy before surgery or in individuals at highest bleeding or thrombotic risk.

Platelet inhibition with ticagrelor versus clopidogrel in Hispanic patients with stable coronary artery disease with or without diabetes mellitus.

PubMed

Clavijo, Leonardo C; Maya, Juan; Carlson, Glenn; Angiolillo, Dominick J; Teng, Renli; Caplan, Richard; Price, Matthew J

2015-12-01

Diabetes mellitus (DM) disproportionately affects Hispanic patients. DM patients have enhanced platelet reactivity and reduced sensitivity to clopidogrel. Ticagrelor demonstrated a more rapid onset and greater magnitude of platelet inhibition than clopidogrel in Hispanic patients with stable coronary artery disease (CAD). This subgroup analysis examined the onset and level of platelet inhibition of ticagrelor and clopidogrel in Hispanic patients with DM. This was a subgroup analysis of a randomized, open-label, crossover study in which 40 Hispanic patients with stable CAD received ticagrelor 180 mg loading dose (LD)/90 mg twice-daily maintenance dose (MD) then clopidogrel 600 mg LD/75 mg once-daily MD, or vice versa. The primary end point was on-treatment platelet reactivity at 2 hours post-LD using the VerifyNow™ P2Y12 test. 21 patients had DM and 19 were non-diabetic. At 2 hours post-LD, mean platelet reactivity in the diabetic group was 34.5 PRU with ticagrelor versus 219.3 PRU with clopidogrel (P<0.001), and in the non-diabetic group was 33.7 PRU with ticagrelor versus 181.0 PRU with clopidogrel (P<0.001). In both diabetic and non-diabetic subgroups, mean platelet reactivity declined to a significantly greater extent with ticagrelor than clopidogrel at all time points evaluated (0.5, 2, and 8 hours post LD and after 7-9 days of MD). Patients were significantly more likely to have high on-treatment platelet reactivity (≥208 PRU) during treatment with clopidogrel compared with ticagrelor, regardless of diabetic status. Among Hispanic patients with stable CAD, ticagrelor achieves a faster onset and greater magnitude of platelet inhibition compared with clopidogrel, irrespective of diabetic status. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Effects of intensive glucose control on platelet reactivity in patients with acute coronary syndromes. Results of the CHIPS Study ("Control de Hiperglucemia y Actividad Plaquetaria en Pacientes con Sindrome Coronario Agudo").

PubMed

Vivas, David; García-Rubira, Juan C; Bernardo, Esther; Angiolillo, Dominick J; Martín, Patricia; Calle-Pascual, Alfonso; Núñez-Gil, Iván; Macaya, Carlos; Fernández-Ortiz, Antonio

2011-05-01

Hyperglycaemia has been associated with increased platelet reactivity and impaired prognosis in patients with acute coronary syndrome (ACS). Whether platelet reactivity can be reduced by lowering glucose in this setting is unknown. The aim of this study was to assess the functional impact of intensive glucose control with insulin on platelet reactivity in patients admitted with ACS and hyperglycaemia. This is a prospective, randomised trial evaluating the effects of either intensive glucose control (target glucose 80-120 mg/dl) or conventional control (target glucose 180 mg/dl or less) with insulin on platelet reactivity in patients with ACS and hyperglycaemia. The primary endpoint was platelet aggregation following stimuli with 20 μM ADP at 24 h and at hospital discharge. Aggregation following collagen, epinephrine and thrombin receptor-activated peptide, as well as P2Y₁₂ reactivity index and surface expression of glycoprotein IIb/IIIa and P-selectin were also measured. Of the 115 patients who underwent random assignment, 59 were assigned to intensive and 56 to conventional glucose control. Baseline platelet functions and inhospital management were similar in both groups. Maximal aggregation after ADP stimulation at hospital discharge was lower in the intensive group (47.9 ± 13.2% vs 59.1 ± 17.3%; p=0.002), whereas no differences were found at 24 h. Similarly all other parameters of platelet reactivity measured at hospital discharge were significantly reduced in the intensive glucose control group. In this randomised trial, early intensive glucose control with insulin in patients with ACS presenting with hyperglycaemia was found to decrease platelet reactivity. Clinical Trial Registration Number http://www.controlledtrials.com/ISRCTN35708451/ISRCTN35708451.

Can tissue adhesives and platelet-rich plasma prevent pharyngocutaneous fistula formation?

PubMed

Eryılmaz, Aylin; Demirci, Buket; Gunel, Ceren; Kacar Doger, Firuzan; Yukselen, Ozden; Kurt Omurlu, Imran; Basal, Yesim; Agdas, Fatih; Basak, Sema

2016-02-01

One of the frequently encountered disorders of wound healing following laryngectomy is pharyngocutaneous fistula. However, although studies have been performed with the aim of prevention of pharyngocutaneous fistulae, there are very few studies with tissue adhesives and platelet-rich plasma. In this study, our aim was to investigate the histopathologic changes in wound healing caused by various tissue adhesives and platelet-rich plasma, together with their effects on prevention of pharyngocutaneous fistula. 40 male rats were randomly divided into five groups: control, platelet-rich plasma, fibrin tissue adhesive, protein-based albumin glutaraldehyde and synthetic tissue adhesive groups. The pharyngotomy procedure was performed and was sutured. Except the control group, tissue adhesives and platelet-rich plasma were applied. Then, the skin was sutured. On the seventh day, the rats were sacrificed. The skin was opened and pharyngotomy site was assessed in terms of fistulae. The pharyngeal suture line was evaluated histopathologically by using Ehrlich Hunt scale. Inflammatory infiltration was found to be higher in "platelet-rich plasma" group than "fibrin tissue adhesive" and "synthetic tissue adhesive" groups. The fibroblastic activity of "platelet-rich plasma", "fibrin tissue adhesive" and "protein-based albumin glutaraldehyde" groups was higher than the control group. The positive changes created by platelet-rich plasma and fibrin tissue adhesive at the histopathologic level were found together with no detected fistula. Among the study groups, there was no statistical difference for pharyngeal fistula development. This result may be obtained by the small number of animal experiments. These results shed light on the suggestion that platelet-rich plasma and fibrin tissue adhesive can be used in clinical studies to prevent pharyngocutaneous fistula. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Increased Platelet Concentration does not Improve Functional Graft Healing in Bio-Enhanced ACL Reconstruction

PubMed Central

Fleming, Braden C.; Proffen, Benedikt L.; Vavken, Patrick; Shalvoy, Matthew R.; Machan, Jason T.; Murray, Martha M.

2014-01-01

Purpose The use of an extra-cellular matrix scaffold (ECM) combined with platelets to enhance healing of an ACL graft (“bio-enhanced ACL reconstruction”) has shown promise in animal models. However, the effects of platelet concentration on graft healing remains unknown. The objectives of this study were to determine if increasing the platelet concentration in the ECM scaffold would; 1) improve the graft biomechanical properties, and 2) decrease cartilage damage after surgery. Methods Fifty-five adolescent minipigs were randomized to 5 treatment groups; untreated ACL transection (n=10), conventional ACL reconstruction (n=15), and bio-enhanced ACL reconstruction using 1X (n=10), 3X (n=10) or 5X (n=10) platelet-rich plasma. The graft biomechanical properties, anteroposterior (AP) knee laxity, graft histology and macroscopic cartilage integrity were measured at 15 weeks. Results The mean linear stiffness of the bio-enhanced ACL reconstruction procedure using the 1X preparation was significantly greater than traditional reconstruction while the 3X and 5X preparations were not. The failure loads of all the ACL reconstructed groups were equivalent but significantly greater than untreated ACL transection. There were no significant differences in the ligament maturity index or AP laxity between reconstructed knees. Macroscopic cartilage damage was relatively minor, though significantly less when the ECM-platelet composite was used. Conclusions Only the 1X platelet concentration improved healing over traditional ACL reconstruction. Increasing the platelet concentration from 1X to 5X in the ECM scaffold did not further improve the graft mechanical properties. The use of an ECM-platelet composite decreased the amount of cartilage damage seen after ACL surgery. PMID:24633008

Increased platelet concentration does not improve functional graft healing in bio-enhanced ACL reconstruction.

PubMed

Fleming, Braden C; Proffen, Benedikt L; Vavken, Patrick; Shalvoy, Matthew R; Machan, Jason T; Murray, Martha M

2015-04-01

The use of an extracellular matrix scaffold (ECM) combined with platelets to enhance healing of an anterior cruciate ligament (ACL) graft ("bio-enhanced ACL reconstruction") has shown promise in animal models. However, the effects of platelet concentration on graft healing remain unknown. The objectives of this study were to determine whether increasing the platelet concentration in the ECM scaffold would (1) improve the graft biomechanical properties and (2) decrease cartilage damage after surgery. Fifty-five adolescent minipigs were randomized to five treatment groups: untreated ACL transection (n = 10), conventional ACL reconstruction (n = 15) and bio-enhanced ACL reconstruction using 1× (n = 10), 3× (n = 10) or 5× (n = 10) platelet-rich plasma. The graft biomechanical properties, anteroposterior (AP) knee laxity, graft histology and macroscopic cartilage integrity were measured at 15 weeks. The mean linear stiffness of the bio-enhanced ACL reconstruction procedure using the 1× preparation was significantly greater than traditional reconstruction, while the 3× and 5× preparations were not. The failure loads of all the ACL-reconstructed groups were equivalent but significantly greater than untreated ACL transection. There were no significant differences in the Ligament Maturity Index or AP laxity between reconstructed knees. Macroscopic cartilage damage was relatively minor, though significantly less when the ECM-platelet composite was used. Only the 1× platelet concentration improved healing over traditional ACL reconstruction. Increasing the platelet concentration from 1× to 5× in the ECM scaffold did not further improve the graft mechanical properties. The use of an ECM-platelet composite decreased the amount of cartilage damage seen after ACL surgery.

Effect of ticagrelor with clopidogrel on high on-treatment platelet reactivity in acute stroke or transient ischemic attack (PRINCE) trial: Rationale and design.

PubMed

Wang, Yilong; Lin, Yi; Meng, Xia; Chen, Weiqi; Chen, Guohua; Wang, Zhimin; Wu, Jialing; Wang, Dali; Li, Jianhua; Cao, Yibin; Xu, Yuming; Zhang, Guohua; Li, Xiaobo; Pan, Yuesong; Li, Hao; Liu, Liping; Zhao, Xingquan; Wang, Yongjun

2017-04-01

Rationale and aim Little is known about the safety and efficacy of the combination of ticagrelor and aspirin in acute ischemic stroke. This study aimed to evaluate whether the combination of ticagrelor and aspirin was superior to that of clopidogrel and aspirin in reducing the 90-day high on-treatment platelet reactivity for acute minor stroke or transient ischemic attack, especially for carriers of cytochrome P450 2C19 loss-of-function allele. Sample size and design This study was designed as a prospective, multicenter, randomized, open-label, active-controlled, and blind-endpoint, phase II b trial. The required sample size was 952 patients. It was registered with ClinicalTrials.gov (NCT02506140). Study outcomes The primary outcome was the proportion of patients with high on-treatment platelet reactivity at 90 days. High on-treatment platelet reactivity is defined as the P2Y12 reaction unit >208 measured using the VerifyNow P2Y12 assay. Conclusion The Platelet Reactivity in Acute Non-disabling Cerebrovascular Events study explored whether ticagrelor combined with aspirin could reduce further the proportion of patients with high on-treatment platelet reactivity at 90 days after acute minor stroke or transient ischemic attack compared with clopidogrel and aspirin.

Evaluation of human platelet lysate versus fetal bovine serum for culture of mesenchymal stromal cells.

PubMed

Hemeda, Hatim; Giebel, Bernd; Wagner, Wolfgang

2014-02-01

Culture media for therapeutic cell preparations-such as mesenchymal stromal cells (MSCs)-usually comprise serum additives. Traditionally, fetal bovine serum is supplemented in basic research and in most clinical trials. Within the past years, many laboratories adapted their culture conditions to human platelet lysate (hPL), which further stimulates proliferation and expansion of MSCs. Particularly with regard to clinical application, human alternatives for fetal bovine serum are clearly to be preferred. hPL is generated from human platelet units by disruption of the platelet membrane, which is commonly performed by repeated freeze and thaw cycles. Such culture supplements are notoriously ill-defined, and many parameters contribute to batch-to-batch variation in hPL such as different amounts of plasma, a broad range of growth factors and donor-specific effects. The plasma components of hPL necessitate addition of anticoagulants such as heparins to prevent gelatinization of hPL medium, and their concentration must be standardized. Labels for description of hPL-such as "xenogen-free," "animal-free" and "serum free"-are not used consistently in the literature and may be misleading if not critically assessed. Further analysis of the precise composition of relevant growth factors, attachment factors, microRNAs and exosomes will pave the way for optimized and defined culture conditions. The use of hPL has several advantages and disadvantages: they must be taken into account because the choice of cell culture additive has major impact on cell preparations. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Human Platelet Lysate as a Replacement for Fetal Bovine Serum in Limbal Stem Cell Therapy.

PubMed

Suri, Kunal; Gong, Hwee K; Yuan, Ching; Kaufman, Stephen C

2016-10-01

To evaluate the use of human platelet lysate (HPL) as an alternative supplement for limbal explant culture. Culture media were prepared using either 10% pooled HPL (PHPL), single donor HPL, or fetal bovine serum (FBS). Limbal tissues, obtained from the Minnesota Lions Eye Bank, were cultured in each medium on plastic plates or on denuded amniotic membrane (AM). Immunofluorescence staining was performed for ABCG2, tumor protein p63α, and cytokeratin 3 (K3). Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used to evaluate the expression of ABCG2 and p63. Limbal explants grown in each medium were labeled with bromodeoxyuridine (BrdU) to assess the proliferative capacity in each medium. Concentration of growth factors including epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), transforming growth factor-β (TGF-β), and platelet derived growth factor (PDGF) in HPL and PHPL was compared to that in human serum (HS). Immunofluorescence staining on AM showed prominent expression of ABCG2, p63α but sparse expression of K3 in HPL and PHPL supplemented medium. Real time-PCR showed 1.7 fold higher expression of ABCG2 in PHPL supplemented medium (p = 0.03), and similar expression of p63 in HPL and PHPL supplemented medium compared to FBS medium. The proliferation assay showed that LSCs retained their proliferative potential in HPL supplemented medium. Higher concentration of growth factors were found in HPL, compared to HS. Human platelet lysate has higher concentration of grown factors and is effective in maintaining growth and stem cell phenotype of corneal limbal explant cultures.

Flow rate calibration to determine cell-derived microparticles and homogeneity of blood components.

PubMed

Noulsri, Egarit; Lerdwana, Surada; Kittisares, Kulvara; Palasuwan, Attakorn; Palasuwan, Duangdao

2017-08-01

Cell-derived microparticles (MPs) are currently of great interest to screening transfusion donors and blood components. However, the current approach to counting MPs is not affordable for routine laboratory use due to its high cost. The current study aimed to investigate the potential use of flow-rate calibration for counting MPs in whole blood, packed red blood cells (PRBCs), and platelet concentrates (PCs). The accuracy of flow-rate calibration was investigated by comparing the platelet counts of an automated counter and a flow-rate calibrator. The concentration of MPs and their origins in whole blood (n=100), PRBCs (n=100), and PCs (n=92) were determined using a FACSCalibur. The MPs' fold-changes were calculated to assess the homogeneity of the blood components. Comparing the platelet counts conducted by automated counting and flow-rate calibration showed an r 2 of 0.6 (y=0.69x+97,620). The CVs of the within-run and between-run variations of flow-rate calibration were 8.2% and 12.1%, respectively. The Bland-Altman plot showed a mean bias of -31,142platelets/μl. MP enumeration revealed both the difference in MP levels and their origins in whole blood, PRBCs, and PCs. Screening the blood components demonstrated high heterogeneity of the MP levels in PCs when compared to whole blood and PRBCs. The results of the present study suggest the accuracy and precision of flow-rate calibration for enumerating MPs. This flow-rate approach is affordable for assessing the homogeneity of MPs in blood components in routine laboratory practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

A detailed examination of platelet function inhibition by nitric oxide in platelet-rich plasma and whole blood.

PubMed

Zimmermann, Robert; Krueger, Julia; Filipović, Milos R; Ivanović-Burmazović, Ivana; Calatzis, Andreas; Weiss, Dominik R; Eckstein, Reinhold

2013-01-01

The question of whether novel instruments such as multiple electrode aggregometry (MEA) can be used for measurement of the effects of nitric oxide (NO) on platelets (PLTs) has not been examined. Therefore, we compared the effects of NO concentrations (1, 10, and 100 microM) on the PLT aggregation response to ADP, arachidonic acid (AA), collagen, ristocetin, and thrombin receptor-activating peptide 6 (TRAP6) using light transmission aggregometry (LTA) and multiple electrode aggregometry (MEA) and examined the effects of NO using the platelet function analyzer (PFA)-100. The response of PLTs to ADP and AA was strongly inhibited by all NO concentrations in LTA and MEA. The inhibition of the responses to ristocetin and collagen was detectable in MEA at lower NO concentrations than in LTA. However, the typically increasing lag phase between collagen addition and the aggregation response in the presence of NO was more obvious in LTA. TRAP caused a reproducible early response in the presence of NO in LTA which was followed by rapid PLT disaggregation, whereas even 100 microM NO did not inhibit the response to TRAP in MEA. Finally, NO prolonged the in-vitro bleeding time remarkably more in the PFA-100 collagen-epinephrin cartridge than in the collagen-ADP cartridge. Whole blood versus PLT rich plasma, citrate versus hirudin, and high versus low shear influenced the effects of NO. This shows that a careful selection of models and potentially a combination of different methods is appropriate for a differentiated evaluation of pharmacological or physiological mechanisms of NO-donors or of NO-inhibitors.

A comparison of the neutrophil-lymphocyte, platelet-lymphocyte and monocyte-lymphocyte ratios in schizophrenia and bipolar disorder patients - a retrospective file review.

PubMed

Özdin, Selçuk; Sarisoy, Gökhan; Böke, Ömer

2017-10-01

Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and monocyte-lymphocyte ratio (MLR) have recently been used as indicators of inflammation. Higher MLR and PLR values have been determined in the euthymic and manic periods in patients with bipolar disorder compared to a control group. High NLR values were determined in the only study investigating this ratio in schizophrenia patients. The purpose of this study was to compare NLR, PLR and MLR values and complete blood count elements in patients receiving treatment and hospitalized due to schizophrenic psychotic episode and bipolar disorder manic episode. All patients meeting the inclusion criteria among subjects receiving treatment and hospitalized due to schizophrenia-psychotic episode and bipolar affective disorder-manic episode at the Ondokuz Mayıs University Medical Faculty Psychiatry Department, Turkey, in 2012-2016 were included in our study. A total of 157 healthy donors were included as a control group. White blood cell (WBC), neutrophil, lymphocyte, platelet and monocyte numbers were noted retrospectively from complete blood counts at time of admission, and NLR, PLR and MLR were calculated from these. NLR, PLR and MLR values and platelet numbers in this study were higher and lymphocyte numbers were lower in bipolar disorder patients compared to the controls. Elevation in NLR, MLR and PLR values and neutrophil numbers and lower lymphocyte numbers were determined in schizophrenia patients compared to the controls. Higher NLR and MLR values were found in schizophrenia patients compared to bipolar disorder. Findings of our study supported the inflammation hypothesis for schizophrenia and bipolar disorder.

The effect of platelet-rich fibrin matrix on rotator cuff tendon healing: a prospective, randomized clinical study.

PubMed

Rodeo, Scott A; Delos, Demetris; Williams, Riley J; Adler, Ronald S; Pearle, Andrew; Warren, Russell F

2012-06-01

There is a strong need for methods to improve the biological potential of rotator cuff tendon healing. Platelet-rich fibrin matrix (PRFM) allows delivery of autologous cytokines to healing tissue, and limited evidence suggests a positive effect of platelet-rich plasma on tendon biology. To evaluate the effect of platelet-rich fibrin matrix on rotator cuff tendon healing. Randomized controlled trial; Level of evidence, 2. Seventy-nine patients undergoing arthroscopic rotator cuff tendon repair were randomized intraoperatively to either receive PRFM at the tendon-bone interface (n = 40) or standard repair with no PRFM (n = 39). Standardized repair techniques were used for all patients. The postoperative rehabilitation protocol was the same in both groups. The primary outcome was tendon healing evaluated by ultrasound (intact vs defect at repair site) at 6 and 12 weeks. Power Doppler ultrasound was also used to evaluate vascularity in the peribursal, peritendinous, and musculotendinous and insertion site areas of the tendon and bone anchor site. Secondary outcomes included standardized shoulder outcome scales (American Shoulder and Elbow Surgeons [ASES] and L'Insalata) and strength measurements using a handheld dynamometer. Patients and the evaluator were blinded to treatment group. All patients were evaluated at minimum 1-year follow-up. A logistic regression model was used to predict outcome (healed vs defect) based on tear severity, repair type, treatment type (PRFM or control), and platelet count. Overall, there were no differences in tendon-to-bone healing between the PRFM and control groups. Complete tendon-to-bone healing (intact repair) was found in 24 of 36 (67%) in the PRFM group and 25 of 31 (81%) in the control group (P = .20). There were no significant differences in healing by ultrasound between 6 and 12 weeks. There were gradual increases in ASES and L'Insalata scores over time in both groups, but there were no differences in scores between the groups. We also found no difference in vascularity in the peribursal, peritendinous, and musculotendinous areas of the tendon between groups. There were no differences in strength between groups. Platelet count had no effect on healing. Logistic regression analysis demonstrated that PRFM was a significant predictor (P = .037) for a tendon defect at 12 weeks, with an odds ratio of 5.8. Platelet-rich fibrin matrix applied to the tendon-bone interface at the time of rotator cuff repair had no demonstrable effect on tendon healing, tendon vascularity, manual muscle strength, or clinical rating scales. In fact, the regression analysis suggests that PRFM may have a negative effect on healing. Further study is required to evaluate the role of PRFM in rotator cuff repair.

Rofecoxib does not compromise platelet aggregation during anesthesia and surgery.

PubMed

Silverman, David G; Halaszynski, Thomas; Sinatra, Raymond; Luther, Martha; Rinder, Christine S

2003-12-01

This study was undertaken because, although there is evidence that cyclooxygenase type 2 (COX)-2 inhibitors do not compromise platelets in healthy volunteers, many clinicians remain hesitant to administer them perioperatively without definitive evidence of intact platelet function during anesthesia and surgery. In 20 patients scheduled for lower abdominal and pelvic surgery, 5 mL of blood were obtained for baseline platelet aggregometry. One hour prior to surgery, patients received an oral solution of either rofecoxib (ROF) 50 mg or placebo (PLAC) by randomized, double-blinded assignment. Approximately one hour after onset of anesthesia, an intraoperative blood sample was obtained. Baseline and postdrug samples were centrifuged to generate platelet-rich plasma, which was challenged with adenosine diphosphate (ADP) and arachidonic acid (AA). Aggregometry was performed with and without incubation with aspirin. The data in each subject were normalized to baseline aggregation in response to AA alone and ADP alone. Intergroup differences were assessed using paired t test; P < 0.05 was considered significant. Consistent with known effects of anesthesia on platelet function, both groups had approximately 25% intraoperative declines in aggregation in response to ADP (P = NS for PLAC vs ROF) and even greater declines in response to AA (P = NS for PLAC vs ROF). Aspirin eliminated aggregation in response to AA in both groups (P = NS), and it caused similar declines in PLAC and ROF groups during exposure to ADP (P = NS). This study provides strong evidence that ROF does not compromise platelet aggregation during anesthesia and surgery; nor does it interfere with the platelet inhibitory effect of aspirin.

The effect of platelet-derived growth factors on knee stability after anterior cruciate ligament reconstruction: a prospective randomized clinical study.

PubMed

Vogrin, Matjaz; Rupreht, Mitja; Crnjac, Anton; Dinevski, Dejan; Krajnc, Zmago; Recnik, Gregor

2010-05-01

Arthroscopic reconstruction is a standard surgical procedure in cases of symptomatic knee instability due to rupture of the anterior cruciate ligament. Bone-tendon-bone and hamstring tendon grafts are both in use for anterior cruciate ligament reconstruction. There are no significant differences between the two types of graft in relation to function scores, but there is a difference in anteroposterior stability when measured on the KT-2000 arthrometer: knee joints after reconstruction with bone-tendon-bone autografts are more stable than those reconstructed with hamstring tendon autografts. To improve knee stability after anterior cruciate ligament reconstruction with a hamstring graft and use of platelet-derived growth factors. Platelet-leukocyte gel was produced from platelet-leukocyte-rich plasma prepared from a unit of whole blood in an autologous platelet separator. The gel was applied locally, after hamstring graft placement. Fifty patients were included in the study: 25 in the platelet gel group, 25 in a control group. We evaluated anteroposterior knee stability with the KT-2000 arthrometer before surgery and at 3 and 6 months after surgery. Patients treated with the gel demonstrated significantly better anteroposterior knee stability than patients in the control group. The calculated improvements in knee stability at 6 months were 1.3 +/- 1.8 mm in the control group and 3.1 +/- 2.5 mm in the platelet gel group (P = 0.011). Platelet-leukocyte gel, applied locally, can improve knee stability in surgery for reconstruction of the anterior cruciate ligament.

Transformation of human mesenchymal cells and skin fibroblasts into hematopoietic cells.

PubMed

Harris, David M; Hazan-Haley, Inbal; Coombes, Kevin; Bueso-Ramos, Carlos; Liu, Jie; Liu, Zhiming; Li, Ping; Ravoori, Murali; Abruzzo, Lynne; Han, Lin; Singh, Sheela; Sun, Michael; Kundra, Vikas; Kurzrock, Razelle; Estrov, Zeev

2011-01-01

Patients with prolonged myelosuppression require frequent platelet and occasional granulocyte transfusions. Multi-donor transfusions induce alloimmunization, thereby increasing morbidity and mortality. Therefore, an autologous or HLA-matched allogeneic source of platelets and granulocytes is needed. To determine whether nonhematopoietic cells can be reprogrammed into hematopoietic cells, human mesenchymal stromal cells (MSCs) and skin fibroblasts were incubated with the demethylating agent 5-azacytidine (Aza) and the growth factors (GF) granulocyte-macrophage colony-stimulating factor and stem cell factor. This treatment transformed MSCs to round, non-adherent cells expressing T-, B-, myeloid-, or stem/progenitor-cell markers. The transformed cells engrafted as hematopoietic cells in bone marrow of immunodeficient mice. DNA methylation and mRNA array analysis suggested that Aza and GF treatment demethylated and activated HOXB genes. Indeed, transfection of MSCs or skin fibroblasts with HOXB4, HOXB5, and HOXB2 genes transformed them into hematopoietic cells. Further studies are needed to determine whether transformed MSCs or skin fibroblasts are suitable for therapy.

Transformation of Human Mesenchymal Cells and Skin Fibroblasts into Hematopoietic Cells

PubMed Central

Harris, David M.; Hazan-Haley, Inbal; Coombes, Kevin; Bueso-Ramos, Carlos; Liu, Jie; Liu, Zhiming; Li, Ping; Ravoori, Murali; Abruzzo, Lynne; Han, Lin; Singh, Sheela; Sun, Michael; Kundra, Vikas; Kurzrock, Razelle; Estrov, Zeev

2011-01-01

Patients with prolonged myelosuppression require frequent platelet and occasional granulocyte transfusions. Multi-donor transfusions induce alloimmunization, thereby increasing morbidity and mortality. Therefore, an autologous or HLA-matched allogeneic source of platelets and granulocytes is needed. To determine whether nonhematopoietic cells can be reprogrammed into hematopoietic cells, human mesenchymal stromal cells (MSCs) and skin fibroblasts were incubated with the demethylating agent 5-azacytidine (Aza) and the growth factors (GF) granulocyte-macrophage colony-stimulating factor and stem cell factor. This treatment transformed MSCs to round, non-adherent cells expressing T-, B-, myeloid-, or stem/progenitor-cell markers. The transformed cells engrafted as hematopoietic cells in bone marrow of immunodeficient mice. DNA methylation and mRNA array analysis suggested that Aza and GF treatment demethylated and activated HOXB genes. Indeed, transfection of MSCs or skin fibroblasts with HOXB4, HOXB5, and HOXB2 genes transformed them into hematopoietic cells. Further studies are needed to determine whether transformed MSCs or skin fibroblasts are suitable for therapy. PMID:21731684

Quality Assessment of Established and Emerging Blood Components for Transfusion

PubMed Central

Marks, Denese C.

2016-01-01

Blood is donated either as whole blood, with subsequent component processing, or through the use of apheresis devices that extract one or more components and return the rest of the donation to the donor. Blood component therapy supplanted whole blood transfusion in industrialized countries in the middle of the twentieth century and remains the standard of care for the majority of patients receiving a transfusion. Traditionally, blood has been processed into three main blood products: red blood cell concentrates; platelet concentrates; and transfusable plasma. Ensuring that these products are of high quality and that they deliver their intended benefits to patients throughout their shelf-life is a complex task. Further complexity has been added with the development of products stored under nonstandard conditions or subjected to additional manufacturing steps (e.g., cryopreserved platelets, irradiated red cells, and lyophilized plasma). Here we review established and emerging methodologies for assessing blood product quality and address controversies and uncertainties in this thriving and active field of investigation. PMID:28070448

Light-scattering flow cytometry for identification and characterization of blood microparticles

NASA Astrophysics Data System (ADS)

Konokhova, Anastasiya I.; Yurkin, Maxim A.; Moskalensky, Alexander E.; Chernyshev, Andrei V.; Tsvetovskaya, Galina A.; Chikova, Elena D.; Maltsev, Valeri P.

2012-05-01

We describe a novel approach to study blood microparticles using the scanning flow cytometer, which measures light scattering patterns (LSPs) of individual particles. Starting from platelet-rich plasma, we separated spherical microparticles from non-spherical plasma constituents, such as platelets and cell debris, based on similarity of their LSP to that of sphere. This provides a label-free method for identification (detection) of microparticles, including those larger than 1 μm. Next, we rigorously characterized each measured particle, determining its size and refractive index including errors of these estimates. Finally, we employed a deconvolution algorithm to determine size and refractive index distributions of the whole population of microparticles, accounting for largely different reliability of individual measurements. Developed methods were tested on a blood sample of a healthy donor, resulting in good agreement with literature data. The only limitation of this approach is size detection limit, which is currently about 0.5 μm due to used laser wavelength of 0.66 μm.

A case of transfusion-transmitted hepatitis E caused by blood from a donor infected with hepatitis E virus via zoonotic food-borne route.

PubMed

Matsubayashi, Keiji; Kang, Jong-Hon; Sakata, Hidekatsu; Takahashi, Kazuaki; Shindo, Motohiro; Kato, Masaru; Sato, Shinichiro; Kato, Toshiaki; Nishimori, Hiroyuki; Tsuji, Kunihiko; Maguchi, Hiroyuki; Yoshida, Jun-Ichi; Maekubo, Hiroshi; Mishiro, Shunji; Ikeda, Hisami

2008-07-01

Five cases of transfusion transmission of hepatitis E virus (HEV) have been reported so far. The infection routes of the causative donors remain unclear, however. Also, the progress of virus markers in the entire course of HEV infection has not been well documented. Nucleic acid testing was performed by real-time reverse transcription-polymerase chain reaction targeting the open reading frame 2 region of HEV. Full-length nucleotide sequences of HEV RNA were detected by direct sequencing. Lookback study of a HEV-positive donor revealed that the platelets (PLTs) donated from him 2 weeks previously contained HEV RNA and were transfused to a patient. Thirteen relatives including the donor were ascertained to enjoy grilled pork meats together in a barbecue restaurant 23 days before the donation. Thereafter, his father died of fulminant hepatitis E and the other 6 members showed serum markers of HEV infection. In the recipient, HEV was detected in serum on Day 22 and reached the peak of 7.2 log copies per mL on Day 44 followed by the steep increase of alanine aminotransferase. Immunoglobulin G anti-HEV emerged on Day 67; subsequently, hepatitis was resolved. HEV RNA sequences from the donor and recipient were an identical, Japan-indigenous strain of genotype 4. HEV RNA was detectable up to Day 97 in serum, Day 85 in feces, and Day 71 in saliva. A transfusion-transmitted hepatitis E case by blood from a donor infected via the zoonotic food-borne route and the progress of HEV markers in the entire course are demonstrated. Further studies are needed to clarify the epidemiology and the transfusion-related risks for HEV even in industrialized countries.

Cord blood serum-based eye drops: the impact of donor haematological and obstetric factors on the variability of epidermal growth factor levels

PubMed Central

Versura, Piera; Buzzi, Marina; Giannaccare, Giuseppe; Grillini, Marco; Terzi, Adriana; Pagliaro, Pasqualepaolo; Campos, Emilio C.

2014-01-01

Background Cord blood serum (CBS)-based eye drops are successfully used in corneal epithelial wound healing and are prepared to supply a known amount of epidermal growth factor (EGF). Product standardisation includes expensive EGF dosage in all cord blood (CB) units. The influence of donor obstetric and haematological characteristics on EGF content was evaluated, to exclude unsuitable CBS and pre-select those CB units able to provide the correct EGF supply for healing corneal wounds. Materials and methods Data were retrospectively collected from 135 donors included in the Emilia Romagna Cord Blood Bank records. Obstetric characteristics, parity and gestational age of the mother, sex, birth weight and Apgar score of the neonate, placental weight, duration of labour and mode of delivery were considered. Haematological characteristics, CD34+ cell number, and total nucleated cell, white blood cell and platelet counts were recorded. EGF content in CB units was estimated by enzyme-linked immunosorbent assay. Statistical evaluation was performed by Mann-Whitney unpaired and Student’s t tests. Correlations between variables were evaluated by using Pearson’s (r) or Spearman’s (ρ) correlation coefficients. Results EGF content was significantly higher in CBS from donors aged <30 years and after vaginal deliveries as compared with scheduled Caesarean sections (1,386±580 vs 1,106±391 pg/mL; P=0.002). EGF content was significantly correlated with duration of labour (r=0.45; P=0.0001), number of CD34+ cells/mL (r=0.3; P=0.002) particularly in vaginal deliveries (r=0.36; P=0.003), mother’s age (−0.25; P=0.005), neonate’s birth weight (r=0.27; P=0.005), and total nucleated cell (r=0.25; P=0.006), white cell (r=0.29; P=0.001) and platelet (r=0.24; P=0.009) counts. No significant correlations were found between EGF content and parity, gestational age, placental weight, neonate’s sex or Apgar scores. Discussion EGF levels are higher in CB units from younger mothers (<30 years), with longer labour duration (>6 hours), and higher CD34+ cell content (>0.05×106/mL). In order to optimise the preparation and costs of CBS–based eye drops, pre-selection of CB units is recommended. PMID:24120597

Effectiveness of educational and social worker interventions to activate patients' discussion and pursuit of preemptive living donor kidney transplantation: a randomized controlled trial.

PubMed

Boulware, L Ebony; Hill-Briggs, Felicia; Kraus, Edward S; Melancon, J Keith; Falcone, Brenda; Ephraim, Patti L; Jaar, Bernard G; Gimenez, Luis; Choi, Michael; Senga, Mikiko; Kolotos, Maria; Lewis-Boyer, LaPricia; Cook, Courtney; Light, Laney; DePasquale, Nicole; Noletto, Todd; Powe, Neil R

2013-03-01

Many patients with chronic kidney disease (CKD) have difficulty becoming actively engaged in the pursuit of preemptive living donor kidney transplantation. The Talking About Live Kidney Donation (TALK) Study was a randomized controlled trial of the effectiveness of educational and social worker interventions designed to encourage early discussions and active pursuit of preemptive living donor kidney transplantation in patients with progressive CKD. We recruited participants with progressive CKD from academically affiliated nephrology practices in Baltimore, MD. Participants randomly received: (1) usual care (routine care with their nephrologists), the (2) TALK education intervention (video and booklet), or the (3) TALK social worker intervention (video and booklet plus patient and family social worker visits). We followed participants for 6 months to assess their self-reported achievement of behaviors reflecting their discussions about and/or pursuit of living donor kidney transplantation (discussions with family, discussions with physicians, initiating recipient evaluation, completing recipient evaluation, and identifying a potential living donor). We assessed outcomes through a questionnaire at 1-, 3-, and 6-months follow-up. Participants receiving usual care with their nephrologists (n = 44), TALK education (n = 43), and the TALK social worker (n = 43) were similar at baseline. TALK Study interventions improved participants' living donor kidney transplantation discussion and pursuit behaviors, with the social worker leading to greater patient activation (participants' predicted probability of achieving living donor kidney transplantation discussions, evaluations, or donor identification over 6 months): probabilities were 30% (95% CI, 20%-46%), 42% (95% CI, 33%-54%), and 58% (95% CI, 41%-83%), respectively, in the usual care, TALK education, and TALK social worker groups (P = 0.03). Our population was well educated and mostly insured, potentially limiting generalizability of our findings. TALK interventions improved discussion and active pursuit of living donor kidney transplantation in patients with progressive CKD and may improve their use of preemptive living donor kidney transplantation. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Immunoglobulin G levels during collection of large volume plasma for fractionation.

PubMed

Burkhardt, Thomas; Rothe, Remo; Moog, Rainer

2017-06-01

There is a need of comprehensive work dealing with the quality of plasma for fractionation with respect to the IgG content as today most plasma derivates are used to treat patients with immunodeficiencies and autoimmune disorders. Therefore, a prospective study was carried out to analyse IgG levels before plasmapheresis and every 200ml collected plasma. Fifty-four experienced plasmapheresis donors were recruited for subsequent 850ml plasmapheresis using the Aurora Plasmapheresis System. Donorś peripheral blood counts were analysed before and after plasmapheresis using an electronic counter. Total protein, IgG and citrate were measured turbidometrically before, during and after apheresis as well as in the plasma product. Furthermore, platelets, red and white blood cells were analysed as parameters of product quality. An average of 2751±247ml blood was processed in 47±6min. The collected plasma volume was 850±1mL and citrate consumption was 177±15mL. A continuous drop of donors' IgG level was observed during plasmapheresis. The drop was 13% of the IgG baseline value at 800mL collected plasma. Total protein, IgG and cell counts of the plasma product met current guidelines of plasma for fractionation. Donors' IgG levels during apheresis showed a steady decrease without compromising the quality of plasma product. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of double dose plateletpheresis on the Fenwal Amicus, Fresenius COM.TEC and Trima Accel cell separators.

PubMed

Keklik, Muzaffer; Eser, Bulent; Kaynar, Leylagul; Solmaz, Musa; Ozturk, Ahmet; Yay, Mehmet; Birekul, Ayse; Oztekin, Mehmet; Sivgin, Serdar; Cetin, Mustafa; Unal, Ali

2014-10-01

A variety of apheresis instruments are now available on the market for double dose plateletpheresis. We compared three apheresis devices (Fenwal Amicus, Fresenius COM.TEC and Trima Accel) with regard to processing time, platelet (PLT) yield, collection efficiency (CE) and collection rate (CR). The single-needle or double-needle double plateletpheresis procedures of the three instruments were compared in a retrospective, randomized study in 135 donors. In the pre-apheresis setting, 45 double plateletpheresis procedures performed with each instrument revealed no significant differences in donor's age, sex, weight, hemoglobin, white blood cell and PLT count between three groups. The blood volume processed to reach a target PLT yield of ≥ 6 × 10(11) was higher in the COM.TEC compared with the Amicus and Trima (4394 vs. 3780 and 3340 ml, respectively; p < 0.001). Also there was a significantly higher median volume of ACD used in collections on the COM.TEC compared with the Amicus and Trima (426 vs. 387 and 329 ml, respectively; p < 0.001). There was a significantly higher median time needed for the procedures on the COM.TEC compared with the Amicus and Trima (66 vs. 62 and 63 min, respectively; p = 0.024). The CE was significantly higher with the Trima compared with the Amicus and COM.TEC (83.57 ± 17.19 vs. 66.71 ± 3.47 and 58.79 ± 5.14%, respectively; p < 0.001). Also, there was a significantly higher product volume on the Trima compared with the Amicus and COM.TEC (395.56 vs. 363.11 and 386.4 ml, respectively; p = 0.008). Additionally, the CR was significantly lower with the COM.TEC compared with the Amicus and Trima (0.092 ± 0.011 vs. 0.099 ± 0.013 and 0.097 ± 0.013 plt × 10(11)/min, respectively; p = 0.039). There was no significant differences in PLT yield between the three groups (p = 0.636). Trima single-needle device collected double dose platelets more efficiently than Amicus and COM.TEC double-needle devices. Blood volume processed, ACD-A volume, and median separation time was significantly higher with the COM.TEC. Also, the CR was significantly lower with the COM.TEC. Copyright © 2014 Elsevier Ltd. All rights reserved.

Short term storage stability at room temperature of two different platelet-rich plasma preparations from equine donors and potential impact on growth factor concentrations.

PubMed

Hauschild, Gregor; Geburek, Florian; Gosheger, Georg; Eveslage, Maria; Serrano, Daniela; Streitbürger, Arne; Johannlükens, Sara; Menzel, Dirk; Mischke, Reinhard

2017-01-05

The increasing interest in platelet-rich plasma (PRP) based therapies is as yet accompanied by inconsistent information regarding nearly all aspects of handling and application. Among these storage stability of processed platelet-rich products may be the basis for a more flexible application mode. The objective of this study was (1) to estimate the storage stability of growth factors platelet derived growth factor BB (PDGF-BB) and transforming growth factor ß1 (TGF-ß1) in both, a single-step softspin centrifugation-based pure-PRP (P-PRP, ACP®), and a gravity filtration system-based leukocyte-rich-PRP (L-PRP, E-PET), over a six hours time span after preparation at room temperature and (2) to identify possible factors influencing these growth factor concentrations in an equine model. Growth factor concentrations remained stable over the entire investigation period in L-PRP as well as P-PRP preparations revealing a mean of 3569 pg/ml PDGF-BB for E-PET and means of 1276 pg/ml PDGF-BB and 5086 pg/ml TGF-ß1 for ACP®. Pearson correlations yielded no significant impact of whole blood platelet (PLT), white blood cell (WBC) and red blood cell (RBC) counts on resulting cytokine values. In case of ACP® no significant dependencies between PLT, WBC and RBC counts of the processed platelet-rich product and resulting cytokine content occurred with exception of TGF-ß1 concentrations showing a strong correlation with the WBC content. PDGF-BB content of E-PET preparations showed a strong positive correlation with PLT and a strong negative with WBC of these preparations but not with RBC. L-PRP ad modum E-PET and P-PRP ad modum ACP® are applicable over at least a six hours time span at room temperature without loss of growth factor content. Based on the results of this study factors influencing the resulting growth factor concentrations still remain questionable. Additional studies implicating a further standardization of preparation protocols are necessary to identify consistent impact on cytokine content after PRP processing.

Effects of intra-articular injection of mesenchymal stem cells associated with platelet-rich plasma in a rabbit model of osteoarthritis.

PubMed

Hermeto, L C; DeRossi, R; Oliveira, R J; Pesarini, J R; Antoniolli-Silva, A C M B; Jardim, P H A; Santana, A E; Deffune, E; Rinaldi, J C; Justulin, L A

2016-09-02

The current study aims to evaluate the macroscopic and histological effects of autologous mesenchymal stem cells (MSC) and platelet-rich plasma on knee articular cartilage regeneration in an experimental model of osteoarthritis. Twenty-four rabbits were randomly divided into four groups: control group, platelet-rich plasma group, autologous MSC undifferentiated group, and autologous MSC differentiated into chondrocyte group. Collagenase solution was used to induce osteoarthritis, and treatments were applied to each group at 6 weeks following osteoarthritis induction. After 60 days of therapy, the animals were euthanized and the articular surfaces were subjected to macroscopic and histological evaluations. The adipogenic, chondrogenic, and osteogenic differentiation potentials of MSCs were evaluated. Macroscopic and histological examinations revealed improved tissue repair in the MSC-treated groups. However, no difference was found between MSC-differentiated and undifferentiated chondrocytes. We found that MSCs derived from adipose tissue and platelet-rich plasma were associated with beneficial effects in articular cartilage regeneration during experimental osteoarthritis.

Glycoprotein IIB/IIIA inhibitor to reduce postpercutaneous coronary intervention myonecrosis and improve coronary flow in diabetics: the 'OPTIMIZE-IT' pilot randomized study.

PubMed

Talarico, Giovanni Paolo; Brancati, Marta; Burzotta, Francesco; Porto, Italo; Trani, Carlo; De Vita, Maria; Todaro, Daniel; Giammarinaro, Maura; Leone, Antonio Maria; Niccoli, Giampaolo; Andreotti, Felicita; Mazzari, Mario Attilio; Schiavoni, Giovanni; Crea, Filippo

2009-03-01

Subgroup analyses of trials enrolling acute coronary syndrome patients suggest that inhibition of glycoprotein IIb/IIIa can improve the outcome of diabetic patients undergoing percutaneous coronary interventions (PCIs), possibly by improving microvascular perfusion. However, the efficacy of small-molecule IIb/IIIa receptor inhibitors to improve microvascular perfusion in stable diabetic patients undergoing elective PCI has not been specifically investigated. We randomized consecutive stable diabetic patients, undergoing elective PCI, to tirofiban or placebo groups along with double antiplatelet therapy. High-dose bolus (25 microg/kg per 3 min) of tirofiban was administered immediately before PCI followed by 8 h continuous infusion (0.15 microg/kg per min). Postprocedural myonecrosis was assessed prospectively by measurement of cardiac troponin T (cTnT) at 6 and 24 h after PCI. The primary end-points were post-PCI coronary flow estimated by corrected thrombolysis in myocardial infarction frame count and post-PCI myocardial infarction. Platelet aggregation was measured by platelet function analyser-100 values. Forty-six patients entered the study (22 randomized to placebo and 24 randomized to tirofiban). The study drug was associated with a significant increase of platelet function analyser-100 values that peaked immediately after PCI and was maintained at 6 h (pre-PCI: 131 +/- 65 s; post-PCI: 222 +/- 49 s; after 6 h: 219 +/- 55 s).Post-PCI corrected thrombolysis in myocardial infarction frame count was similar in tirofiban and in placebo groups (10.2 +/- 3.6 vs. 12.0 +/- 7.6, P = 0.30, respectively). The prevalence of raised cTnT levels was similar in the two groups (25 vs. 30%, P = 0.56, respectively). At multivariate analysis, direct stenting (associated with reduced myonecrosis) and postdilatation (associated with increased myonecrosis) predicted cTnT elevation. A high-dose bolus of tirofiban in stable diabetic patients undergoing elective PCI, along with double antiplatelet therapy, was associated with a significant further inhibition of platelet aggregation which, however, did not translate in a lower incidence of post-PCI distal embolization.

Fetal and neonatal alloimmune thrombocytopenia: evidence based antenatal and postnatal management strategies.

PubMed

Winkelhorst, Dian; Oepkes, Dick; Lopriore, Enrico

2017-08-01

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a relatively rare but potentially lethal disease, leading to severe bleeding complications in 1 in 11.000 newborns. It is the leading cause of thrombocytopenia in healthy term-born neonates. Areas covered: This review summarizes the antenatal as well as postnatal treatment, thus creating a complete overview of all possible management strategies for FNAIT. Expert commentary: The optimal antenatal therapy in order to prevent bleeding complications in pregnancies complicated by FNAIT is non-invasive treatment with weekly intravenous immunoglobulin (IVIG). Based on risk stratification, weekly doses of IVIG of 0.5 or 1.0g/kg should be administered started early in the second in high risk cases or at the end of the second trimester in low risk cases. The optimal postnatal treatment depends on the platelet count and the clinical condition of the newborn. Prompt administration of compatible platelet transfusion is the first treatment of choice in case of severe thrombocytopenia or active bleeding. In case matched platelets are not directly available, random platelets can also be administered initially to gain time until matched platelets are available. In case of persistent thrombocytopenia despite transfusions, IVIG 1.0-2.0g/kg can be administered.

Effect of chronic treatment with acetylsalicylic acid and clopidogrel on atheroprogression and atherothrombosis in ApoE-deficient mice in vivo.

PubMed

Schulz, Christian; Konrad, Ildiko; Sauer, Susanne; Orschiedt, Lena; Koellnberger, Maria; Lorenz, Reinhard; Walter, Ulrich; Massberg, Steffen

2008-01-01

Acetylsalicylic acid (ASA) and the thienopyridine clopidogrel are established anti-platelet drugs that significantly reduce secondary cardiovascular events in patients with manifest atherosclerosis. However, their impact on atherosclerotic lesion development remains controversial. Four-week-old ApoE-deficient mice were randomly assigned to four groups receiving a cholesterol diet together with either ASA (5 mg/kg), or clopidogrel (25 mg/kg), or a combination of both ASA and clopidogrel, or vehicle for 8-12 weeks. Using intravital microscopy we found that daily administration of ASA in combination with clopidogrel reduces platelet thrombus formation following rupture of atherosclerotic plaque in vivo by approximately 50%. However, therapy with ASA or clopidogrel alone, or in combination for a period of 8-12 weeks had no significant effect on adhesion of platelets to dysfunctional endothelial cells or on atherosclerotic lesion formation in the aortic root or the carotid artery. In conclusion, anti-platelet therapy is effective in reducing platelet adhesion and subsequent thrombus formation following rupture of atherosclerotic plaque in vivo. However, our data do not support a role of either drug in the primary prevention of atherosclerosis in ApoE-deficient mice.

Broadband and polarization reflectors in the lookdown, Selene vomer.

PubMed

Zhao, Shulei; Brady, Parrish Clawson; Gao, Meng; Etheredge, Robert Ian; Kattawar, George W; Cummings, Molly E

2015-03-06

Predator evasion in the open ocean is difficult because there are no objects to hide behind. The silvery surface of fish plays an important role in open water camouflage. Various models have been proposed to account for the broadband reflectance by the fish skin that involve one-dimensional variations in the arrangement of guanine crystal reflectors, yet the three-dimensional organization of these guanine platelets have not been well characterized. Here, we report the three-dimensional organization and the optical properties of integumentary guanine platelets in a silvery marine fish, the lookdown (Selene vomer). Our structural analysis and computational modelling show that stacks of guanine platelets with random yaw angles in the fish skin produce broadband reflectance via colour mixing. Optical axes of the guanine platelets and the collagen layer are aligned closely and provide bulk birefringence properties that influence the polarization reflectance by the skin. These data demonstrate how the lookdown preserves or alters polarization states at different incident polarization angles. These optical properties resulted from the organization of these guanine platelets and the collagen layer may have implications for open ocean camouflage in varying light fields. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

The Biomechanical and Histologic Effects of Platelet-Rich Plasma on Rat Rotator Cuff Repairs

PubMed Central

Beck, Jennifer; Evans, Douglas; Tonino, Pietro M.; Yong, Sherri; Callaci, John J.

2013-01-01

Background Rotator cuff tears are common injuries that are often treated with surgical repair. Because of the high concentration of growth factors within platelets, platelet-rich plasma (PRP) has the potential to enhance healing in rotator cuff repairs. Hypothesis Platelet-rich plasma would alter the biomechanical and histologic properties of rotator cuff repair during an acute injury response. Study Design Controlled laboratory study. Methods Platelet-rich plasma was produced from inbred donor rats. A tendon-from-bone supraspinatus tear was created surgically and an immediate transosseous repair performed. The control group underwent repair only. The PRP group underwent a repair with PRP augmentation. Rats in each group were sacrificed at 7, 14, and 21 days. The surgically repaired tendons underwent biomechanical testing, including failure load, stiffness, failure strain, and stress relaxation characteristics. Histological analysis evaluated the cellular characteristics of the repair tissue. Results At 7- and 21-day periods, augmentation with PRP showed statistically significant effects on the biomechanical properties of the repaired rat supraspinatus tear, but failure load was not increased at the 7-, 14-, or 21-day periods (P = .688, .209, and .477, respectively). The control group had significantly higher stiffness at 21 days (P = .006). The control group had higher failure strain at 7 days (P = .02), whereas the PRP group had higher failure strain at 21 days (P = .008). Histologically, the PRP group showed increased fibroblastic response and vascular proliferation at each time point. At 21 days, the collagen fibers in the PRP group were oriented in a more linear fashion toward the tendon footprint. Conclusion In this controlled, rat model study, PRP altered the tissue properties of the supraspinatus tendon without affecting the construct’s failure load. Clinical Relevance The decreased tendon tissue stiffness acutely and failure to enhance tendon-to-bone healing of repairs should be considered before augmenting rotator cuff repairs with PRP. Further studies will be necessary to determine the role of PRP in clinical practice. PMID:22822177

Manufacture of Autologous CD34+ Selected Grafts in the NIAID-Sponsored HALT-MS and SCOT Multicenter Clinical Trials for Autoimmune Diseases.

PubMed

Keever-Taylor, Carolyn A; Heimfeld, Shelly; Steinmiller, Kaitlyn C; Nash, Richard A; Sullivan, Keith M; Czarniecki, Christine W; Granderson, Tomeka C; Goldstein, Julia S; Griffith, Linda M

2017-09-01

To ensure comparable grafts for autologous hematopoietic cell transplantation (HCT) in the National Institute of Allergy and Infectious Diseases-sponsored Investigational New Drug protocols for multiple sclerosis (HALT-MS) and systemic sclerosis (SCOT), a Drug Master File approach to control manufacture was implemented, including a common Master Production Batch Record and site-specific standard operating procedures with "Critical Elements." We assessed comparability of flow cytometry and controlled rate cryopreservation among sites and stability of cryopreserved grafts using hematopoietic progenitor cells (HPCs) from healthy donors. Hematopoietic Progenitor Cells, Apheresis-CD34+ Enriched, for Autologous Use (Auto-CD34 + HPC) graft specifications included ≥70% viable CD34 + cells before cryopreservation. For the 2 protocols, 110 apheresis collections were performed; 121 lots of Auto-CD34 + HPC were cryopreserved, and 107 of these (88.4%) met release criteria. Grafts were infused at a median of 25 days (range, 17 to 68) post-apheresis for HALT-MS (n = 24), and 25 days (range, 14 to 78) for SCOT (n = 33). Subjects received precryopreservation doses of a median 5.1 × 10 6 viable CD34 + cells/kg (range, 3.9 to 12.8)  for HALT-MS and 5.6 × 10 6 viable CD34 + cells/kg (range, 2.6 to 10.2) for SCOT. Recovery of granulocytes occurred at a median of 11 days (range, 9 to 15) post-HCT for HALT-MS and 10 days (range, 8 to 12) for SCOT, independent of CD34 + cell dose. Subjects received their last platelet transfusion at a median of 9 days (range, 6 to 16) for HALT-MS and 8 days (range, 6 to 23) for SCOT; higher CD34 + /kg doses were associated with faster platelet recovery. Stability testing of cryopreserved healthy donor CD34 + HPCs over 6 months of vapor phase liquid nitrogen storage demonstrated consistent 69% to 73% recovery of viable CD34 + cells. Manufacturing of Auto-CD34 + HPC for the HALT-MS and SCOT protocols was comparable across all sites and supportive for timely recovery of granulocytes and platelets. Published by Elsevier Inc.

Hematopoietic stem cell transplantation donor sources in the 21st century: choosing the ideal donor when a perfect match does not exist.

PubMed

Kekre, Natasha; Antin, Joseph H

2014-07-17

Most patients who require allogeneic stem cell transplantation do not have a matched sibling donor, and many patients do not have a matched unrelated donor. In an effort to increase the applicability of transplantation, alternative donors such as mismatched adult unrelated donors, haploidentical related donors, and umbilical cord blood stem cell products are frequently used when a well matched donor is unavailable. We do not yet have the benefit of randomized trials comparing alternative donor stem cell sources to inform the choice of donor; however, the existing data allow some inferences to be made on the basis of existing observational and phase 2 studies. All 3 alternative donor sources can provide effective lymphohematopoietic reconstitution, but time to engraftment, graft failure rate, graft-versus-host disease, transplant-related mortality, and relapse risk vary by donor source. These factors all contribute to survival outcomes and an understanding of them should help guide clinicians when choosing among alternative donor sources when a matched related or matched unrelated donor is not available. © 2014 by The American Society of Hematology.

Hematopoietic Progenitor Cell Mobilization is More Robust in Healthy African American Compared to Caucasian Donors and is not Affected by the Presence of Sickle Cell Trait

PubMed Central

Panch, Sandhya R.; Yau, Yu Ying; Fitzhugh, Courtney D.; Hsieh, Matthew M.; Tisdale, John F.; Leitman, Susan F.

2016-01-01

Background G-CSF-stimulated hematopoietic progenitor cells (HPCs) collected by apheresis have become the predominant graft source for HPC transplantation in adults. Among healthy allogeneic donors, demographic characteristics (age, sex, BMI) and baseline hematologic counts affect HPC mobilization, leading to variability in CD34+ apheresis yields. Racial differences in HPC mobilization are less well characterized. Methods We retrospectively analyzed data from 1,096 consecutive G-CSF-stimulated leukapheresis procedures in healthy allogeneic African American (AA) or Caucasian donors. Results In a multivariate analysis, after adjusting for age, sex, BMI, baseline platelet and MNC counts, and daily G-CSF dose, peak CD34+ cell mobilization was significantly higher among AAs (n=215) than Caucasians (n=881) (123 ± 87 vs 75 ± 47 cells/uL; p<0.0001). A ceiling effect was observed with increasing G-CSF dose (10 vs 16 mcg/kg/day) in AAs (123 ± 88 vs 123 ± 87) but not in Caucasians (74 ± 46 vs 93 ± 53, p<0.001). In AA donors, presence of sickle cell trait (SCT, n=41) did not affect CD34+ mobilization (peak CD34+ 123 ± 91 vs 107 ±72 cells/uL, HbAS vs HbAA, p=0.34). Adverse events were minimal and similar across race. Conclusions AAs demonstrated significantly better CD34 mobilization responses to G-CSF than Caucasians. This was independent of other demographic and hematologic parameters. Studying race-associated pharmacogenomics in relation to G-CSF may improve dosing strategies. Adverse event profile and CD34 mobilization were similar in AA donors with and without SCT. Our findings suggest that it would be safe to include healthy AA donors with SCT in unrelated donor registries. PMID:27167356

[Effects of organic selenium supplement on glutathione peroxidase activities: a meta-analysis of randomized controlled trials].

PubMed

Jiang, Xia; Dong, Jiayi; Wang, Bo; Yin, Xuebin; Qin, Liqiang

2012-01-01

To study the effects of organic selenium supplementation on glutathione peroxidase (GPx) activities. Randomized controlled trials (RCT) published from January 1988 to December 2010 on the relationship between organic selenium supplementation and GPx activities were collected. Meta-analysis was applied to estimate the combined standardized mean difference (SMD) and 95% confidence interval (95% CI). A total of 10 RCTs were included. The number of studies observing GPx activities in plasma, erythrocyte and platelet was 8, 5 and 5, respectively. Compared with the controls, the combined SMD (95% CI) of GPx activities in plasma, erythrocyte and platelet of subjects supplemented with organic selenium was 0.46 (0.09 - 0.83), 0.36 (0.02 - 0.69) and 0.56 (-0.02 - 1.15). Supplementation with organic selenium increases GPx activities in healthy adults.

The effect of the perfluorocarbon emulsion Oxycyte on platelet count and function in the treatment of decompression sickness in a swine model.

PubMed

Cronin, William A; Senese, Angela L; Arnaud, Francoise G; Regis, David P; Auker, Charles R; Mahon, Richard T

2016-09-01

Decompression from elevated ambient pressure is associated with platelet activation and decreased platelet counts. Standard treatment for decompression sickness (DCS) is hyperbaric oxygen therapy. Intravenous perfluorocarbon (PFC) emulsion is a nonrecompressive therapy being examined that improves mortality in animal models of DCS. However, PFC emulsions are associated with a decreased platelet count. We used a swine model of DCS to study the effect of PFC therapy on platelet count, function, and hemostasis. Castrated male swine (n = 50) were fitted with a vascular port, recovered, randomized, and compressed to 180 feet of sea water (fsw) for 31 min followed by decompression at 30 fsw/min. Animals were observed for DCS, administered 100% oxygen, and treated with either emulsified PFC Oxycyte (DCS-PFC) or isotonic saline (DCS-NS). Controls underwent the same procedures, but were not compressed (Sham-PFC and Sham-NS). Measurements of platelet count, thromboelastometry, and coagulation were obtained 1 h before compression and 1, 24, 48, 96, 168 and 192 h after treatment. No significant changes in normalized platelet counts were observed. Prothrombin time was elevated in DCS-PFC from 48 to 192 h compared with DCS-NS, and from 96 to 192 h compared with Sham-PFC. Normalized activated partial thromboplastin time was also elevated in DCS-PFC from 168 to 192 h compared with Sham-PFC. No bleeding events were noted. DCS treated with PFC (Oxycyte) does not impact platelet numbers, whole blood clotting by thromboelastometry, or clinical bleeding. Late changes in prothrombin time and activated partial thromboplastin time associated with PFC use in both DCS therapy and controls warrant further investigation.

Chronic Plantar Fasciitis: Effect of Platelet-Rich Plasma, Corticosteroid, and Placebo.

PubMed

Mahindra, Pankaj; Yamin, Mohammad; Selhi, Harpal S; Singla, Sonia; Soni, Ashwani

2016-01-01

Plantar fasciitis is a common cause of heel pain. It is a disabling disease in its chronic form. It is a degenerative tissue condition of the plantar fascia rather than an inflammation. Various treatment options are available, including nonsteroidal anti-inflammatory drugs, corticosteroid injections, orthosis, and physiotherapy. This study compared the effects of local platelet-rich plasma, corticosteroid, and placebo injections in the treatment of chronic plantar fasciitis. In this double-blind study, patients were divided randomly into 3 groups. Local injections of platelet-rich plasma, corticosteroid, or normal saline were given. Patients were assessed with the visual analog scale for pain and with the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle and Hindfoot score before injection, at 3 weeks, and at 3-month follow-up. Mean visual analog scale score in the platelet-rich plasma and corticosteroid groups decreased from 7.44 and 7.72 preinjection to 2.52 and 3.64 at final follow-up, respectively. Mean AOFAS score in the platelet-rich plasma and corticosteroid groups improved from 51.56 and 55.72 preinjection to 88.24 and 81.32 at final follow-up, respectively. There was a significant improvement in visual analog scale score and AOFAS score in the platelet-rich plasma and corticosteroid groups at 3 weeks and at 3-month follow-up. There was no significant improvement in visual analog scale score or AOFAS score in the placebo group at any stage of the study. The authors concluded that local injection of platelet-rich plasma or corticosteroid is an effective treatment option for chronic plantar fasciitis. Platelet-rich plasma injection is as effective as or more effective than corticosteroid injection in treating chronic plantar fasciitis. Copyright 2016, SLACK Incorporated.

Use of tailored loading-dose clopidogrel in patients undergoing selected percutaneous coronary intervention based on adenosine diphosphate-mediated platelet aggregation.

PubMed

Meng, Kang; Lü, Shu-Zheng; Zhu, Hua-Gang; Chen, Xin; Ge, Chang-Jiang; Song, Xian-Tao

2010-12-01

Adenosine phosphate-mediated platelet aggregation is a prognostic factor for major adverse cardiac events in patients who have undergone selective percutaneous coronary interventions. This study aimed to assess whether an adjusted loading dose of clopidogrel could more effectively inhibit platelet aggregation in patients undergoing selected percutaneous coronary intervention. A total of 205 patients undergoing selected percutaneous coronary intervention were enrolled in this multicenter, prospective, randomized study. Patients receiving domestic clopidogrel (n = 104) served as the Talcom (Taijia) group; others (n = 101) received Plavix, the Plavix group. Patients received up to 3 additional 300-mg loading doses of clopidogrel to decrease the adenosine phosphate-mediated platelet aggregation index by more than 50% (the primary endpoint) compared with the baseline. The secondary endpoint was major adverse cardiovascular events at 12 months. Compared with the rational loading dosage, the tailored loading dosage better inhibited platelet aggregation based on a > 50% decrease in adenosine phosphate-mediated platelet aggregation (rational loading dosage vs. tailored loading dosage, 48% vs. 73%, P = 0.028). There was no significant difference in the eligible index between the Talcom and Plavix groups (47% vs. 49% at 300 mg; 62% vs. 59% at 600 mg; 74% vs. 72% at 900 mg; P > 0.05) based on a standard adenosine diphosphate-mediated platelet aggregation decrease of > 50%. After 12 months of follow-up, there were no significant differences in major adverse cardiac events (2.5% vs. 2.9%, P = 5.43). No acute or subacute stent thrombosis events occurred. An adjusted loading dose of clopidogrel could have significant effects on antiplatelet aggregation compared with a rational dose, decreasing 1-year major adverse cardiac events in patients undergoing percutaneous coronary interventions based on adenosine phosphate-mediated platelet aggregation with no increase in bleeding.

In vitro inhibition of platelets aggregation with generic form of clopidogrel versus branded in patients with stable angina pectoris.

PubMed

Hajizadeh, Rza; Ghaffari, Samad; Ziaee, Mojtaba; Shokouhi, Behrooz; Separham, Ahmad; Sarbakhsh, Parvin

2017-01-01

Introduction: Clopidogrel is a potent platelet activation and aggregation inhibitor that prevents thrombosis in coronary artery diseases (CADs). In comparison to locally produced generic one (Osvix®), original brand of clopidogrel (Plavix®) is expensive. This study was designed to evaluate the effectiveness and uniformity of Osvix® versus Plavix® in patients with percutaneous coronary intervention (PCI) by means of platelet aggregation indexes. Methods: This randomized, double blind clinical study was conducted at Shahid Madani heart hospital, Tabriz, Iran, and 129 patients with previous PCI were enrolled in two independent treatment groups. All patients participated in this study were on dual antiplatelet therapy at least for 30 days. ASA 80 mg/d and clopidogrel 75 mg/d and a stat dose of 300 mg of clopidogrel before PCI were administered for all patients. To evaluate the anti-platelet activity, blood samples were taken from the patients and platelet aggregation test was performed. Results: The total study population represents a group of 129 patients (99 men and 30 women) with mean age of 57.7 ± 9.7 years with stable angina pectoris. The baseline characteristics and laboratory findings of two groups (except mean platelet volume [MPV]) were not different statistically. The mean platelets aggregation at 30th day was 13.7±7.0 in Plavix® group and 14.8±5.8 in Osvix® group ( P value = 0.35). Conclusion: This study showed that Osvix® as a generic form of clopidogrel was not significantly different from the original brand (Plavix) in terms of in vitro platelet inhibition.

Platelet lysate mucohadesive formulation to treat oral mucositis in graft versus host disease patients: a new therapeutic approach.

PubMed

Del Fante, Claudia; Perotti, Cesare; Bonferoni, Maria Cristina; Rossi, Silvia; Sandri, Giuseppina; Ferrari, Franca; Scudeller, Luigia; Caramella, Carla Marcella

2011-09-01

Optimal treatment of oral mucositis (OM) due to graft versus host disease (GvHD) is currently not available. Platelet-derived growth factors (PDGFs) have high capability for tissue healing and may play a role in repairing the mucosal barrier. The aim of the present work was to develop a mucoadhesive formulation to administer platelet lysate to oral cavity prolonging contact time of platelet lysate with oral mucosa. The mucoadhesive formulation was characterized for in vitro properties (PDGF-AB concentration, mucoadhesive properties, cytotoxicity, fibroblast proliferation, wound healing). Moreover, a preliminary clinical study on seven GvHD patients with OM refractory to other therapies was conducted, to evaluate feasibility, safety, and efficacy. GVPL (mucoadhesive gel vehicle mixed with platelet lysate)showed good mucoadhesive properties; additionally, it was characterized by good biocompatibility in vitro on fibroblasts and it was able to enhance fibroblast proliferation and wound healing, maintaining the efficacy for up to 14 days following storage at 2-8°C. In vivo, clinical response was good-to-complete in five, fair in one, none in the remaining one. The in vitro results indicate that GVPL has optimal mucoadhesive and healing enhancer properties, maintained over time (up to 14 days); preliminary clinical results suggest that oral application of platelet lysate-loaded mucoadhesive formulation is feasible, safe, well tolerated, and effective. A larger controlled randomized study is needed.

[IMPACT OF ATORVASTATIN AND ROSUVASTATIN ON RESIDUAL ON-CLOPIDOGREL TREATMENT PLATELET REACTIVITY IN PATIENTS WITH ISCHEMIC HEART DISEASE AND TYPE 2 DIABETES MELLITUS AFTER ACUTE CORONARY SYNDROME].

PubMed

Ovrakh, T; Serik, S; Kochubiei, O

2017-04-01

In patients with ischemic heart disease and type 2 diabetes mellitus in 4-6 weeks after acute coronary syndrome (ACS) on stable dual antiplatelet therapy (DAPT) with aspirin and clopidogrel co-adminstrated with rosuvastatin residual platelet reactivity on adenosine diphosphate was higher than in patients receiving atorvastatin. However, the rate of high residual on-clopidogrel treatment platelet reactivity (RCPR) in rosuvastatin-treated patients exceeded the rate of high RCPR in atorvastatin-treated patients insignificantly. In 6 months after ACS residual platelet reactivity did not differ between the groups. After 12 months of DAPT platelet reactivity increased as compared to baseline values both in patients receiving rosuvastatin and in patients receiving atorvastatin without switching. In patients, randomly switching from one statin type to another at 6 month of treatment, platelet reactivity did not change significantly in comparison to baseline and the prevalence of high RCPR was lower than in patients receiving statins without switching. Thus, in patients with diabetes with ACS on DAPT with acetylsalicylic acid and clopidogrel statin treatment should be started with atorvastatin and in 6 months after ACS atorvastatin should be switched to rosuvastatin. This approach will provide lower RCPR within at least first 4-6 weeks after ACS and prevent RCPR increase during 12 months of DATT use in this patients group.

The separation distance distribution in electron-donor-acceptor systems and the wavelength dependence of free ion yields

NASA Astrophysics Data System (ADS)

Zhou, Jinwei; Findley, Bret R.; Braun, Charles L.; Sutin, Norman

2001-06-01

We recently reported that free radical ion quantum yields for electron-donor-acceptor (EDA) systems of alkylbenzenes-tetracyanoethylene (TCNE) exhibit a remarkable wavelength dependence in dichloromethane, a medium polarity solvent. We proposed that weak absorption by long-distance, unassociated or "random" D⋯A pairs is mainly responsible for the free radical ion yield. Here a model for the wavelength dependence of the free ion yield is developed for four systems in which differing degrees of EDA complex formation are present: 1,3,5-tri-tert-butylbenzene-TCNE in which only random pairs exist due to the bulky groups on the electron donor, and toluene—TCNE, 1,3,5-triethylbenzene-TCNE and 1,3,5-trimethylbenzene-TCNE. Mulliken-Hush theory is used to determine the excitation distance distribution of unassociated, random pairs at different wavelengths. For each absorption distribution, free radical ion yields at different wavelengths are then calculated using Onsager's result for the ion separation probability. Encouraging agreement between the calculated yields and our experimental results is obtained. As far as we are aware, this is the first time that photoexcitation of unassociated donor/acceptor pairs has been invoked as the source of separated radical ion pairs.

Reconstituted fresh whole blood improves clinical outcomes compared with stored component blood therapy for neonates undergoing cardiopulmonary bypass for cardiac surgery: a randomized controlled trial.

PubMed

Gruenwald, Colleen E; McCrindle, Brian W; Crawford-Lean, Lynn; Holtby, Helen; Parshuram, Christopher; Massicotte, Patricia; Van Arsdell, Glen

2008-12-01

This study compared the effects of reconstituted fresh whole blood against standard blood component therapy in neonates undergoing cardiac surgery. Patients less than 1 month of age were randomized to receive either reconstituted fresh whole blood (n = 31) or standard blood component therapy (n = 33) to prime the bypass circuit and for transfusion during the 24 hours after cardiopulmonary bypass. Primary outcome was chest tube drainage; secondary outcomes included transfusion needs, inotrope score, ventilation time, and hospital length of stay. Patients who received reconstituted fresh whole blood had significantly less postoperative chest tube volume loss per kilogram of body weight (7.7 mL/kg vs 11.8 mL/kg; P = .03). Standard blood component therapy was associated with higher inotropic score (6.6 vs 3.3; P = .002), longer ventilation times (164 hours vs 119 hours; P = .04), as well as longer hospital stays (18 days vs 12 days; P = .006) than patients receiving reconstituted fresh whole blood. Of the different factors associated with the use of reconstituted fresh whole blood, lower platelet counts at 10 minutes and at the end of cardiopulmonary bypass, older age of cells used in the prime and throughout bypass, and exposures to higher number of allogeneic donors were found to be independent predictors of poor clinical outcomes. Reconstituted fresh whole blood used for the prime, throughout cardiopulmonary bypass, and for all transfusion requirements within the first 24 hours postoperatively results in reduced chest tube volume loss and improved clinical outcomes in neonatal patients undergoing cardiac surgery.

Triple-Loaded Single-Row Versus Suture-Bridge Double-Row Rotator Cuff Tendon Repair With Platelet-Rich Plasma Fibrin Membrane: A Randomized Controlled Trial.

PubMed

Barber, F Alan

2016-05-01

To compare the structural healing and clinical outcomes of triple-loaded single-row with suture-bridging double-row repairs of full-thickness rotator cuff tendons when both repair constructs are augmented with platelet-rich plasma fibrin membrane. A prospective, randomized, consecutive series of patients diagnosed with full-thickness rotator cuff tears no greater than 3 cm in anteroposterior length were treated with a triple-loaded single-row (20) or suture-bridging double-row (20) repair augmented with platelet-rich plasma fibrin membrane. The primary outcome measure was cuff integrity by magnetic resonance imaging (MRI) at 12 months postoperatively. Secondary clinical outcome measures were American Shoulder and Elbow Surgeons, Rowe, Simple Shoulder Test, Constant, and Single Assessment Numeric Evaluation scores. The mean MRI interval was 12.6 months (range, 12-17 months). A total of 3 of 20 single-row repairs and 3 of 20 double-row repairs (15%) had tears at follow-up MRI. The single-row group had re-tears in 1 single tendon repair and 2 double tendon repairs. All 3 tears failed at the original attachment site (Cho type 1). In the double-row group, re-tears were found in 3 double tendon repairs. All 3 tears failed medial to the medial row near the musculotendinous junction (Cho type 2). All clinical outcome measures were significantly improved from the preoperative level (P < .0001), but there was no statistical difference between groups postoperatively. There is no MRI difference in rotator cuff tendon re-tear rate at 12 months postsurgery between a triple-loaded single-row repair or a suture-bridging double-row repair when both are augmented with platelet-rich plasma fibrin membrane. No difference could be demonstrated between these repairs on clinical outcome scores. I, Prospective randomized study. Copyright © 2016 Arthroscopy Association of North America. All rights reserved.

Role of xenogenous bovine platelet gel embedded within collagen implant on tendon healing: an in vitro and in vivo study

PubMed Central

Oryan, Ahmad; Meimandi-Parizi, Abdolhamid; Maffulli, Nicola

2015-01-01

Surgical reconstruction of large Achilles tendon defects is demanding. Platelet concentrates may be useful to favor healing in such conditions. The characteristics of bovine platelet-gel embedded within a collagen-implant were determined in vitro, and its healing efficacy was examined in a large Achilles tendon defect in rabbits. Two cm of the left Achilles tendon of 60 rabbits were excised, and the animals were randomly assigned to control (no implant), collagen-implant, or bovine-platelet-gel-collagen-implant groups. The tendon edges were maintained aligned using a Kessler suture. No implant was inserted in the control group. In the two other groups, a collagen-implant or bovine-platelet-gel-collagen-implant was inserted in the defect. The bioelectricity and serum platelet-derived growth factor levels were measured weekly and at 60 days post injury, respectively. After euthanasia at 60 days post injury, the tendons were tested at macroscopic, microscopic, and ultrastructural levels, and their dry matter and biomechanical performances were also assessed. Another 60 rabbits were assigned to receive no implant, a collagen-implant, or a bovine-platelet-gel-collagen-implant, euthanized at 10, 20, 30, and 40 days post injury, and their tendons were evaluated grossly and histologically to determine host-graft interactions. Compared to the control and collagen-implant, treatment with bovine-platelet-gel-collagen-implant improved tissue bioelectricity and serum platelet-derived growth factor levels, and increased cell proliferation, differentiation, and maturation. It also increased number, diameter, and density of the collagen fibrils, alignment and maturation of the collagen fibrils and fibers, biomechanical properties and dry matter content of the injured tendons at 60 days post injury. The bovine-platelet-gel-collagen-implant also increased biodegradability, biocompatibility, and tissue incorporation behavior of the implant compared to the collagen-implant alone. This treatment also decreased tendon adhesion, muscle fibrosis, and atrophy, and improved the physical activity of the animals. The bovine-platelet-gel-collagen-implant was effective in neotenon formation in vivo, which may be valuable in the clinical setting. PMID:25341879

Anger, frustration, boredom and the Department of Motor Vehicles: Can negative emotions impede organ donor registration?

PubMed

Siegel, Jason T; Tan, Cara N; Rosenberg, Benjamin D; Navarro, Mario A; Thomson, Andrew L; Lyrintzis, Elena A; Alvaro, Eusebio M; Jones, Natalie D

2016-03-01

The IIFF Model (Information, Immediate and Complete Registration Mechanism, Focused Engagement, Favorable Activation) offers a checklist of considerations for interventions seeking to influence organ donor registration behavior. One aspect of the model, favorable activation, recommends considering the emotional and motivational state of a potential donor registrant. Given that most donor registrations occur at the Department of Motor Vehicles (DMV), we considered whether emotions experienced while at the DMV could influence registration rates. The current research effort investigated the emotions people experience while visiting the DMV, explored whether these emotions are associated with donor registration intentions, and experimentally assessed whether DMV experiences influence donor registration. Three studies were conducted through Amazon's Mechanical Turk. In Study 1, we randomly assigned participants to either recall a prior DMV experience or to a comparison condition. Emotions associated with the recalled experiences were the dependent variable. Study 2 assessed the correlations between nine different emotions and donor registration intentions. Study 3 randomly assigned participants to recall a prior frustrating DMV experience or to a comparison condition. Intention to register to donate was the dependent variable. Study 1 found that recalling a prior DMV experience was associated with more negative and less positive emotions than the comparison condition. Study 2 found that increased levels of negative emotion could be problematic, as negative emotions were associated with decreased donor intentions. Study 3 found that recalling a frustrating DMV experience resulted in significantly lower intentions to register as an organ donor (vs. a control condition). Although not all DMV experiences are negative, these data indicated a relationship between the DMV and negative emotions; an association between negative emotions and lower donor registration intentions; and, a causal relationship between negative DMV experiences and decreased registration intentions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Culture of human cell lines by a pathogen-inactivated human platelet lysate.

PubMed

Fazzina, R; Iudicone, P; Mariotti, A; Fioravanti, D; Procoli, A; Cicchetti, E; Scambia, G; Bonanno, G; Pierelli, L

2016-08-01

Alternatives to the use of fetal bovine serum (FBS) have been investigated to ensure xeno-free growth condition. In this study we evaluated the efficacy of human platelet lysate (PL) as a substitute of FBS for the in vitro culture of some human cell lines. PL was obtained by pools of pathogen inactivated human donor platelet (PLT) concentrates. Human leukemia cell lines (KG-1, K562, JURKAT, HL-60) and epithelial tumor cell lines (HeLa and MCF-7) were cultured with either FBS or PL. Changes in cell proliferation, viability, morphology, surface markers and cell cycle were evaluated for each cell line. Functional characteristics were analysed by drug sensitivity test and cytotoxicity assay. Our results demonstrated that PL can support growth and expansion of all cell lines, although the cells cultured in presence of PL experienced a less massive proliferation compared to those grown with FBS. We found a comparable percentage of viable specific marker-expressing cells in both conditions, confirming lineage fidelity in all cultures. Functionality assays showed that cells in both FBS- and PL-supported cultures maintained their normal responsiveness to adriamycin and NK cell-mediated lysis. Our findings indicate that PL is a feasible serum substitute for supporting growth and propagation of haematopoietic and epithelial cell lines with many advantages from a perspective of process standardization, ethicality and product safety.

Simultaneous genotyping of HPA-17w to -21w by PCR-SSP in Chinese Cantonese.

PubMed

Zhou, Haojie; Ding, Haoqiang; Chen, Yangkai; Li, Xiaofan; Ye, Xin; Nie, Yongmei

2015-01-01

Studies have reported the polymorphism of human platelet antigen (HPA)-17w, -18w, -19w, -20w, and -21w. However, the distribution of these five antigens in Chinese Cantonese is still unknown. In this study, we designed new sequence-specific primers for HPA-19w to -21w and used published primers for HPA-17w and -18w to develop a polymerase chain reaction with the sequence-specific primers (PCR-SSP) method for simultaneously genotyping HPA-17w to -21w. A total of 820 unrelated Cantonese apheresis platelet donors in Guangzhou were involved in this study. Among the five HPAs, complete a/a homozygosity was observed for HPA-17w to -20w with an allele frequency of 1.0000. For HPA-21w, nine individuals (9/820, 1.10%) were found to be HPA-21a/bw heterozygous and the allele frequencies of HPA-21a and HPA-21bw were 0.9945 (1631/1640) and 0.0055 (9/1640), respectively. The reliability of the PCR-SSP method was determined by comparing with the genotyping results by DNA sequencing, and no inconsistencies were observed between the two methods. This study provides a reliable PCR-SSP method for simultaneously genotyping HPA-17w to -21w and could improve HPA-matched platelet transfusion in Chinese Cantonese.

The use of indium-111 labeled platelet scanning for the detection of asymptomatic deep venous thrombosis in a high risk population

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siegel, R.S.; Rae, J.L.; Ryan, N.L.

Five hundred indium-111 labeled platelet imaging studies (387 donor and 113 autologous) were performed postoperatively in 473 patients who had undergone total hip replacement, total knee replacement, or internal fixation of a hip fracture to detect occult deep venous thrombosis. All patients had been anticoagulated prophylactically with aspirin, warfarin sodium (Coumadin), or dextran. Thirty-four possible cases of proximal deep venous thrombosis were identified in 28 asymptomatic patients. To verify the scan results, 31 venograms were performed in 25 patients (three refused). In 21 of 31 cases, totally occlusive thrombi were detected; in 5 cases, partially occlusive thrombi were detected; inmore » 5 cases, no thrombus was seen. No patient who had a negative scan nor any patient who had a verified positive scan (and received appropriate heparin therapy) subsequently developed symptoms or signs of pulmonary embolism. One hundred forty-one indium study patients also underwent Doppler ultrasonography/impedance plethysmography (Doppler/IPG) as a comparative non-invasive technique. In 137 cases, the results of the indium study and Doppler/IPG studies were congruent. The indium study had no false negative results that were detected by Doppler/IPG. No patient had any clinically evident toxicity. These results suggest that indium-111 labeled platelet scanning is a safe, noninvasive means for identifying DVT in high risk patients.« less

Three to six year follow-up of normal donors who received recombinant human granulocyte colony-stimulating factor.

PubMed

Cavallaro, A M; Lilleby, K; Majolino, I; Storb, R; Appelbaum, F R; Rowley, S D; Bensinger, W I

2000-01-01

One hundred and one donors who had received filgrastim (rhG-CSF) for the purpose of donating either granulocytes or peripheral blood stem cells (PBSC) for their relatives more than 3 years ago were contacted. All donors had received daily rhG-CSF at a median dose of 16 microg/kg/day (range 3-16) for a median of 6 days (range 3-15 days). All collection procedures were completed and short-term side-effects of rhG-CSF were mild in the majority of the donors. At a median time interval of 43.13 months (range 35-73), the donors were contacted to assess whether adverse effects related to rhG-CSF administration had occurred. Prior to rhG-CSF two donors had cancer, one had a myocardial infarction, one was hepatitis C virus positive, one had a history of sinusitis, one had Graves' disease and two had arterial hypertension. None worsened with the rhG-CSF administration but the donor with a history of infarction had an episode of angina following apheresis, and the donor with Graves' disease had a stroke 15 months after rhG-CSF. Two pregnancies occurred after the rhG-CSF administration and one donor was 2-3 weeks pregnant during rhG-CSF treatment. Three pregnancies resulted in two normal births and one in a spontaneous abortion of a pregnancy which occurred more than 2 years following rhG-CSF. In the time following rhG-CSF administration two donors developed cancer (breast and prostate cancer) at a follow-up of 70 and 11 months, respectively. One donor developed lymphadenopathy 38 months after the rhG-CSF, which spontaneously resolved. Blood counts were obtained in 70 donors at a median follow up of 40.4 months (range 16.8-70.8). Hematocrit was 43% (median, range 36.8-48), white blood cells were 5.7 x 109/l (median, range 3-14), granulocytes 3.71 x 109/l (median, range 1. 47-10.36), lymphocytes 1.67 x 109/l (median, range 0.90-3.96), monocytes 0.46 x 109/l (median, range 0.07-0.87) and platelet counts were 193.0 x 109/l (median, range 175.0-240.0). This study indicates that short-term administration of rhG-CSF to normal donors for the purpose of mobilizing the PBSC or granulocytes appears safe and without any obvious adverse effects more than 3 years after the donation. Bone Marrow Transplantation (2000) 25, 85-89.

One-unit versus two-unit cord-blood transplantation for hematologic cancers.

PubMed

Wagner, John E; Eapen, Mary; Carter, Shelly; Wang, Yanli; Schultz, Kirk R; Wall, Donna A; Bunin, Nancy; Delaney, Colleen; Haut, Paul; Margolis, David; Peres, Edward; Verneris, Michael R; Walters, Mark; Horowitz, Mary M; Kurtzberg, Joanne

2014-10-30

Umbilical-cord blood has been used as the source of hematopoietic stem cells in an estimated 30,000 transplants. The limited number of hematopoietic cells in a single cord-blood unit prevents its use in recipients with larger body mass and results in delayed hematopoietic recovery and higher mortality. Therefore, we hypothesized that the greater numbers of hematopoietic cells in two units of cord blood would be associated with improved outcomes after transplantation. Between December 1, 2006, and February 24, 2012, a total of 224 patients 1 to 21 years of age with hematologic cancer were randomly assigned to undergo double-unit (111 patients) or single-unit (113 patients) cord-blood transplantation after a uniform myeloablative conditioning regimen and immunoprophylaxis for graft-versus-host disease (GVHD). The primary end point was 1-year overall survival. Treatment groups were matched for age, sex, self-reported race (white vs. nonwhite), performance status, degree of donor-recipient HLA matching, and disease type and status at transplantation. The 1-year overall survival rate was 65% (95% confidence interval [CI], 56 to 74) and 73% (95% CI, 63 to 80) among recipients of double and single cord-blood units, respectively (P=0.17). Similar outcomes in the two groups were also observed with respect to the rates of disease-free survival, neutrophil recovery, transplantation-related death, relapse, infections, immunologic reconstitution, and grade II-IV acute GVHD. However, improved platelet recovery and lower incidences of grade III and IV acute and extensive chronic GVHD were observed among recipients of a single cord-blood unit. We found that among children and adolescents with hematologic cancer, survival rates were similar after single-unit and double-unit cord-blood transplantation; however, a single-unit cord-blood transplant was associated with better platelet recovery and a lower risk of GVHD. (Funded by the National Heart, Lung, and Blood Institute and the National Cancer Institute; ClinicalTrials.gov number, NCT00412360.).

Carbon Monoxide and Nitric Oxide Mediate Cytoskeletal Reorganization in Microvascular Cells via Vasodilator-Stimulated Phosphoprotein Phosphorylation

PubMed Central

Li Calzi, Sergio; Purich, Daniel L.; Chang, Kyung Hee; Afzal, Aqeela; Nakagawa, Takahiko; Busik, Julia V.; Agarwal, Anupam; Segal, Mark S.; Grant, Maria B.

2008-01-01

OBJECTIVE— We examined the effect of the vasoactive agents carbon monoxide (CO) and nitric oxide (NO) on the phosphorylation and intracellular redistribution of vasodilator-stimulated phosphoprotein (VASP), a critical actin motor protein required for cell migration that also controls vasodilation and platelet aggregation. RESEARCH DESIGN AND METHODS— We examined the effect of donor-released CO and NO in endothelial progenitor cells (EPCs) and platelets from nondiabetic and diabetic subjects and in human microvascular endothelial cells (HMECs) cultured under low (5.5 mmol/l) or high (25 mmol/l) glucose conditions. VASP phosphorylation was evaluated using phosphorylation site-specific antibodies. RESULTS— In control platelets, CO selectively promotes phosphorylation at VASP Ser-157, whereas NO promotes phosphorylation primarily at Ser-157 and also at Ser-239, with maximal responses at 1 min with both agents on Ser-157 and at 15 min on Ser-239 with NO treatment. In diabetic platelets, neither agent resulted in VASP phosphorylation. In nondiabetic EPCs, NO and CO increased phosphorylation at Ser-239 and Ser-157, respectively, but this response was markedly reduced in diabetic EPCs. In endothelial cells cultured under low glucose conditions, both CO and NO induced phosphorylation at Ser-157 and Ser-239; however, this response was completely lost when cells were cultured under high glucose conditions. In control EPCs and in HMECs exposed to low glucose, VASP was redistributed to filopodia-like structures following CO or NO exposure; however, redistribution was dramatically attenuated under high glucose conditions. CONCLUSIONS— Vasoactive gases CO and NO promote cytoskeletal changes through site- and cell type–specific VASP phosphorylation, and in diabetes, blunted responses to these agents may lead to reduced vascular repair and tissue perfusion. PMID:18559661

Activation of platelet-rich plasma using soluble type I collagen.

PubMed

Fufa, Duretti; Shealy, Blake; Jacobson, May; Kevy, Sherwin; Murray, Martha M

2008-04-01

Platelet-rich plasma (PRP) has recently been found to be a useful delivery system for growth factors important to oral tissue healing. But application of PRP in a liquid form to a wound site within the oral cavity can be complicated by significant loss of the PRP into the surrounding oral space unless gelation through the clotting mechanism is accomplished. Gelation is currently accomplished using bovine thrombin; however, rare but serious complications of this method have led to the search for alternative clotting mechanisms, including the use of soluble collagen as a clotting activator. In this work, our hypothesis was that soluble type I collagen would be as effective as bovine thrombin in causing clotting of the PRP and stimulating growth factor release from the platelets and granulocytes. PRP from human donors was clotted using type I collagen or bovine thrombin. Clot retraction was determined by measuring clot diameters over time. The release of platelet-derived growth factor (PDGF)-AB, transforming growth factor (TGF)-beta1, and vascular endothelial growth factor (VEGF) from both types of clots was measured over 10 days using enzyme-linked immunosorbent assasy. Clots formed using type I collagen exhibited far less retraction than those formed with bovine thrombin. Bovine thrombin and type I collagen stimulated similar release of PDGF-AB and VEGF between 1 and 10 days; however, thrombin activation resulted in a greater release of TGF-beta1 during the first 5 days after activation. The use of type I collagen to activate clotting of PRP may be a safe and effective alternative to bovine thrombin. The use of collagen results in less clot retraction and equal release of PDGF-AB and VEGF compared with currently available methods of clot activation.

Plasma glycoprotein V levels in the general population: normal distribution, associated parameters and implications for clinical studies.

PubMed

Aleil, Boris; Meyer, Nicolas; Wolff, Valérie; Kientz, Daniel; Wiesel, Marie-Louise; Gachet, Christian; Cazenave, Jean-Pierre; Lanza, François

2006-10-01

Soluble glycoprotein V (sGPV) is a new plasma marker of thrombosis released from the platelet surface by thrombin. sGPV levels are increased in patients with atherothrombotic diseases, but the determinants of sGPV levels are unknown in the general population. Identification of these potential confounding factors is needed for correct design and analysis of clinical studies on cardiovascular diseases. The aim of this study was to determine the normal range of plasma values and the factors controlling sGPV levels in a population of normal individuals. Three hundred blood donors were recruited at the Etablissement Français du Sang-Alsace for the measurement of plasma levels of sGPV, platelet factor 4 (PF4), thrombin-antithrombin complexes (TAT) and D-dimers. The plasma level of sGPV was (median [interquartile range]) 27.5 [23.5-34.4] microg/l and displayed a Gaussian distribution. sGPV had a lower interindividual coefficient of variation (33%) than PF4 (176%), TAT (87%) or D-dimers (82%). sGPV levels were independent of age and sex but sensitive to red cell (r = 0.412; p < 0.0001) and platelet counts (r = 0.267; p = 0.001), total cholesterol (r = -0.313; p < 0.0001), food intake (r = 0.184; p = 0.0014) and smoking (r = -0.154; p = 0.039). Contrary to PF4 and TAT, sGPV did not differ between venous and arterial blood samples of 12 healthy individuals. Red cell and platelet counts, total cholesterol, current smoking and recent food intake are important determinants of sGPV levels and must be taken into account in clinical studies using sGPV as a thrombosis marker. Normal distribution of sGPV levels in the general population supports its use in clinical applications.

Determining the effect of vein visualization technology on donation success, vasovagal symptoms, anxiety and intention to re-donate in whole blood donors aged 18-30 years: A randomized controlled trial.

PubMed

Waller, D; Mondy, P; Brama, T; Fisher, J; King, A; Malkov, K; Wall-Smith, D; Ryan, L; Irving, D O

2016-08-01

Vein visualization technology (VVT) devices use near-infrared light to assist location of peripheral veins. The current study investigated the impact of VVT on donor experience and collection success for young blood donors at the Australian Red Cross Blood Service. The study in donors aged 18 to 30 years used a two intervention to one control randomized trial design with 285 new and 587 returning donors recruited at two sites. Donors reported presyncopal symptoms, phlebotomy pain, anxiety and intentions to redonate along with other measures. Participating phlebotomists rated usefulness of the technology. Flow rates, collection volumes and other donation information were taken from routine data. No significant differences were found between control and intervention groups on presyncopal symptoms, phlebotomy pain, anxiety, intentions to redonate, flow rates, collection volumes or vasovagal reactions (all P's > 0·05). Phlebotomist ratings of VVT were significantly more positive when they had less than 5 years of experience (P < 0·01) or when the vein was not visible to the naked eye (P < 0·01). Results suggest that VVT does not improve the donation experience for younger blood donors. Staff reports indicate that VVT may have some utility for assisting with difficult phlebotomies. © 2016 International Society of Blood Transfusion.

The association of platelets with failed patent ductus arteriosus closure after a primary course of indomethacin or ibuprofen: a systematic review and meta-analysis.

PubMed

Mitra, Souvik; Chan, Anthony K; Paes, Bosco A

2017-01-01

To conduct a meta-analysis of the association of platelet counts and pharmacotherapeutic failure in preterms with a patent ductus arteriosus (PDA). MEDLINE, Embase, Science Citation Index, abstracts and conference proceedings were searched, and principal authors contacted. Included studies reported indomethacin or ibuprofen use for PDA closure, compared a group which failed treatment versus a group which did not and reported the association between platelet counts and indomethacin or ibuprofen failure. Two reviewers independently screened results and assessed methodological quality using the Newcastle-Ottawa Scale. Results are expressed as mean difference in platelet counts and summary odds ratios (OR) using a random effects model. 1105 relevant studies were identified; eight involving 1087 preterms were included. Platelet counts were significantly lower in infants who failed pharmacotherapy (Meandifference:-30.88 × 10 9 /L; 95% CI:-45.69 × 10 9 ,-16.07 × 10 9 /L; I2 = 24%; p heterogeneity  =   0.24). Similar results were obtained based on either pharmacotherapeutic agent. Treatment failure was also significantly associated with pre-treatment thrombocytopenia (summary OR:1.75; 95% CI:1.23-2.49, I2 = 36%, p heterogeneity  =   0.20). Platelet counts are significantly lower in preterms who fail primary treatment for PDA. Pre-treatment thrombocytopenia is associated with higher odds of failure. Further cohort studies reporting platelet counts in prostaglandin inhibitor failure are needed for meta-analyses to firmly establish or refute a stronger association.

Preoperative platelet transfusions to reverse antiplatelet therapy for urgent non-cardiac surgery: an observational cohort study.

PubMed

Baschin, M; Selleng, S; Hummel, A; Diedrich, S; Schroeder, H W; Kohlmann, T; Westphal, A; Greinacher, A; Thiele, T

2018-04-01

Essentials An increasing number of patients requiring surgery receive antiplatelet therapy (APT). We analyzed 181 patients receiving presurgery platelet transfusions to reverse APT. No coronary thrombosis occurred after platelet transfusion. This justifies a prospective trial to test preoperative platelet transfusions to reverse APT. Background Patients receiving antiplatelet therapy (APT) have an increased risk of perioperative bleeding and cardiac adverse events (CAE). Preoperative platelet transfusions may reduce the bleeding risk but may also increase the risk of CAE, particularly coronary thrombosis in patients after recent stent implantation. Objectives To analyze the incidence of perioperative CAE and bleeding in patients undergoing non-cardiac surgery using a standardized management of transfusing two platelet concentrates preoperatively and restart of APT within 24-72 h after surgery. Methods A cohort of consecutive patients on APT treated with two platelet concentrates before non-cardiac surgery between January 2012 and December 2014 was retrospectively identified. Patients were stratified by the risk of major adverse cardiac and cerebrovascular events (MACCE). The primary objective was the incidence of CAE (myocardial infarction, acute heart failure and cardiac troponine T increase). Secondary objectives were incidences of other thromboembolic events, bleedings, transfusions and mortality. Results Among 181 patients, 88 received aspirin, 21 clopidogrel and 72 dual APT. MACCE risk was high in 63, moderate in 103 and low in 15 patients; 67 had cardiac stents. Ten patients (5.5%; 95% CI, 3.0-9.9%) developed a CAE (three myocardial infarctions, four cardiac failures and three troponin T increases). None was caused by coronary thrombosis. Surgery-related bleeding occurred in 22 patients (12.2%; 95% CI, 8.2-17.7%), making 12 re-interventions necessary (6.6%; 95% CI, 3.8-11.2%). Conclusion Preoperative platelet transfusions and early restart of APT allowed urgent surgery and did not cause coronary thromboses, but non-thrombotic CAEs and re-bleeding occurred. Randomized trials are warranted to test platelet transfusion against other management strategies. © 2018 International Society on Thrombosis and Haemostasis.

A randomized comparative prospective study of platelet-rich plasma, platelet-rich fibrin, and hydroxyapatite as a graft material for mandibular third molar extraction socket healing.

PubMed

Dutta, Shubha Ranjan; Passi, Deepak; Singh, Purnima; Sharma, Sarang; Singh, Mahinder; Srivastava, Dhirendra

2016-01-01

The purpose of this study was to compare the efficacy of platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and hydroxyapatite (HA) for reduction of pain and swelling, absence of dry socket, soft tissue healing, and bone regeneration after mandibular third molar extraction in human patients. Forty patients requiring extraction of mandibular third molars were randomly grouped as control, PRP, PRF, and HA-treated. The patients were assessed for postoperative pain, swelling, dry socket, and soft tissue healing on the 3 rd , 7 th , and 14 th day of postoperative periods depending on the standard methods. Radiological assessment of the extraction site was done at 1, 2, and 6 months interval to compare the change in bone density in the sockets in control and treated patients. Pain and swelling were less on PRP and PRF site when compared to HA and control site. PRP and PRF site showed better soft tissue healing when compared to HA and control site. Radiographic assessment showed comparatively lesser bone density values in PRP, PRF, and control site at 1, 2, and 6 months than HA site. Our study showed that PRP and PRF are better graft materials than HA regarding pain, swelling, dry socket, and soft tissue healing. Bone regeneration is induced promptly by HA as compared to other graft materials. However, a more elaborate study with a larger number of clinical cases is very much essential to be more conclusive regarding the efficacy of the graft materials.

A randomized comparative prospective study of platelet-rich plasma, platelet-rich fibrin, and hydroxyapatite as a graft material for mandibular third molar extraction socket healing

PubMed Central

Dutta, Shubha Ranjan; Passi, Deepak; Singh, Purnima; Sharma, Sarang; Singh, Mahinder; Srivastava, Dhirendra

2016-01-01

Aim: The purpose of this study was to compare the efficacy of platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and hydroxyapatite (HA) for reduction of pain and swelling, absence of dry socket, soft tissue healing, and bone regeneration after mandibular third molar extraction in human patients. Materials and Methods: Forty patients requiring extraction of mandibular third molars were randomly grouped as control, PRP, PRF, and HA-treated. The patients were assessed for postoperative pain, swelling, dry socket, and soft tissue healing on the 3rd, 7th, and 14th day of postoperative periods depending on the standard methods. Radiological assessment of the extraction site was done at 1, 2, and 6 months interval to compare the change in bone density in the sockets in control and treated patients. Results: Pain and swelling were less on PRP and PRF site when compared to HA and control site. PRP and PRF site showed better soft tissue healing when compared to HA and control site. Radiographic assessment showed comparatively lesser bone density values in PRP, PRF, and control site at 1, 2, and 6 months than HA site. Conclusion: Our study showed that PRP and PRF are better graft materials than HA regarding pain, swelling, dry socket, and soft tissue healing. Bone regeneration is induced promptly by HA as compared to other graft materials. However, a more elaborate study with a larger number of clinical cases is very much essential to be more conclusive regarding the efficacy of the graft materials. PMID:28163478

Has platelet-rich plasma any role in anterior cruciate ligament allograft healing?

PubMed

Nin, Juan Ramón Valentí; Gasque, Gonzalo Mora; Azcárate, Andrés Valentí; Beola, Jesús Dámaso Aquerreta; Gonzalez, Milagros Hernandez

2009-11-01

The aim of this study was to evaluate and compare the clinical and inflammatory parameters with the addition of platelet-derived growth factor (PDGF) in primary anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone allograft. We prospectively randomized 100 patients undergoing arthroscopic patellar tendon allograft ACL reconstruction to a group in whom platelet-enriched gel was used (n = 50) and a non-gel group (n = 50). The platelet concentration was 837 x 10(3)/mm(3), and the gel was introduced inside the graft and the tibial tunnel. Demographic data were comparable between groups. The mean follow-up was 24 months for both groups and included a history, clinical evaluation with the International Knee Documentation Committee score, radiographs, and magnetic resonance imaging. There were no differences in the number of associated injuries. The results did not show any statistically significant differences between the groups for inflammatory parameters (perimeters of the knee and C-reactive protein level), magnetic resonance imaging appearance of the graft, and clinical evaluation scores (visual analog scale, International Knee Documentation Committee, and KT-1000 arthrometer [MEDmetric, San Diego, CA]). At this time, the therapeutic role of PDGF in ACL reconstruction remains unclear. The use of PDGF, on the graft and inside the tibial tunnel, in patients treated with bone-patellar tendon-bone allografts has no discernable clinical or biomechanical effect at 2 years' follow-up. More clinical studies will be needed to show the efficacy and use of these factors in daily practice in ACL reconstruction. Level I, prospective, randomized, double-blind study.

Allogeneic Transplantation: Peripheral Blood versus Bone Marrow

PubMed Central

Bensinger, William I.

2013-01-01

Purpose of Review Peripheral Blood Stem Cells (PBSC) have been widely adopted as a source of stem cells for allogeneic transplantation although controversy remains regarding their role compared to the use of bone marrow (BM). Recent Findings Ten year follow-up has been reported from several large randomized trials and a recently completed trial using unrelated donor stem cells have been reported. In addition, two meta-analyses have been reported from the findings of a number of randomized studies. Several studies indicate that PBSC confer survival advantages over BM with matched sibling donors for most disease categories except where the risks of disease recurrence within the first year are low, but with the extra risk of more chronic GVHD. Using PBSC from unrelated donors does not appear to be more beneficial than BM, but with early follow-up. New strategies for rapid mobilization of PBSC from normal donors using plerixafor have been reported. Early studies suggest that filgrastim stimulated BM may confer some of the advantages of PBSC without the risks of chronic GVHD. Summary PBSC are a preferred source of stem cells for many types of allogeneic transplant where matched related donors are available. Whether the same benefits accrue from unrelated donors will require further follow-up. PMID:22185938

Interaction of clopidogrel and statins in secondary prevention after cerebral ischaemia – a randomized, double-blind, double-dummy crossover study

PubMed Central

Siepmann, Timo; Heinke, Denise; Kepplinger, Jessica; Barlinn, Kristian; Gehrisch, Siegmund; Grählert, Xina; Schwanebeck, Uta; Reichmann, Heinz; Puetz, Volker; Bodechtel, Ulf; Gahn, Georg

2014-01-01

Aims Variability in responsiveness to clopidogrel is a clinical problem in secondary prevention after cerebral ischaemia which has been suggested to be linked to competitive metabolization of clopidogrel and cytochrome P450 (CYP) 3A4-oxidated statins such as simvastatin. We assessed the hypothesis that simvastatin, in contrast to CYP 2C9-metabolized fluvastatin, reduces clopidogrel-mediated platelet inhibition. Methods We performed a randomized, double-blind, double-dummy, two period crossover study in 13 patients with cerebral ischaemia (8F, 5 M), aged 64.1 ± 8.0 years (mean ± SD). After a 14 day period in which all patients received 75 mg clopidogrel day−1, patients additionally received either 20 mg simvastatin day−1 or 80 mg fluvastatin day−1 for 14 days. Regimens were crossed over after a 14 day wash-out period and switched regimens were continued for another 14 days. Platelet aggregation, clopidogrel active metabolite (CAM) plasma concentrations and routine laboratory parameters including prothrombin time (PT) Quick percent value were assessed at baseline and following each treatment phase. Results Clopidogrel reduced platelet aggregation in all patients as expected. Platelet aggregation and CAM plasma concentrations were unaltered when simvastatin or fluvastatin was added to clopidogrel. Simvastatin decreased PT Quick percent value (decrease from 109 ± 10.5% to 103 ± 11%, P < 0.05) when combined with clopidogrel but there was no such change following treatment with fluvastatin and clopidogrel. Conclusions Our data indicate that treatment with CYP 3A4-metabolized simvastatin does not jeopardize clopidogrel-mediated inhibition of platelet aggregation. After co-administration of simvastatin and clopidogrel we observed a decrease in the PT Quick percent value which could be due to simvastatin-induced reduction of activity of prothrombin fragment 1 + 2. PMID:24803100

Use of biosimilar filgrastim compared with lenograstim in autologous haematopoietic stem-cell transplant and in sibling allogeneic transplant

PubMed Central

Uddin, Shab; Russell, Pippa; Farrell, Maresa; Davy, Barbara; Taylor, Joe

2015-01-01

Objectives: Biosimilar filgrastim was compared with lenograstim for autologous haematopoietic stem-cell transplant (HSCT) in patients with haematological malignancies. Data from a separate group of sibling donors who underwent allogeneic HSCT are also reported. Methods: Patients with lymphoma or multiple myeloma (MM) who underwent autologous HSCT with biosimilar filgrastim were compared with a historical control group of patients who received lenograstim. Peripheral blood (PB) cells counts were monitored after 7–8 consecutive days of granulocyte-colony stimulating factor (G-CSF) injection and apheresis was performed on day 8 if PB CD34+ cell count was ⩾10 cells/µl. The target PB CD34+ cell doses were ⩾2.0 × 106/kg (lymphoma), ⩾4.0 × 106/kg (MM ⩾60 years old) or ⩾8.0 × 106/kg (MM <60 years old). Results: A total of 259 patients were included in the autologous HSCT comparison (biosimilar filgrastim, n = 104; lenograstim, n = 155). In patients with lymphoma and older MM patients (⩾60 years old), no significant differences were observed between groups with regard to stem-cell mobilization parameters. However, in MM patients <60 years old, all parameters were significantly superior in the biosimilar filgrastim group, including the need for 1 rather than 2 apheresis procedures. No significant differences were observed between groups in median number of days to absolute neutrophil count (ANC) or platelet recovery. In the allogeneic setting, 47 sibling donors received biosimilar filgrastim. Mean CD34+ count at the first apheresis was 6.1 × 106/kg. A total of 13 donors needed a second apheresis and 4 required a third. Among recipients, median days to ANC recovery was 16 (10–28) and to platelet recovery was 13 (9–54). Conclusions: Biosimilar filgrastim is as effective as lenograstim for autologous HSCT in patients with lymphoma or MM patients ⩾60 years old. However, mobilization with biosimilar filgrastim appeared to be superior to that with lenograstim in younger MM patients. PMID:25830013

Effects of structured education program on organ donor designation of nursing students and their families: A randomized controlled trial.

PubMed

Murakami, Minoru; Fukuma, Shingo; Ikezoe, Masaya; Iizuka, Chizuko; Izawa, Satoshi; Yamamoto, Yosuke; Yamazaki, Shin; Fukuhara, Shunichi

2016-11-01

Little is known about the effect of education programs on changing attitudes and behaviors of participants and their families toward deceased organ donation. The subjects of this randomized trial were Japanese nursing students who were not previously designated organ donors. They were randomly assigned to either the education program or information booklet group. The program comprised a lecture followed by group discussion and information booklet. The primary outcome was self-reported organ donor designation. Outcomes were assessed by questionnaire. Data of 203 (99.0%) students were analyzed. At study end, seven of 102 students (6.9%) of the program group and one of 101 students (1.0%) of the booklet group consented to donate organs (proportion ratio 6.93 [95% CI 0.87-55.32]). There were significant between-group differences in willingness to consent for donation (54.9% vs 39.6%; proportion ratio 1.39 [95% CI 1.03-1.87]), family discussion (31.4% vs 15.9%; 1.98 [1.16-3.38]), and organ donor designation of family members (11.8% vs 2.0%; 5.94 [1.36-25.88]). No group differences were found in willingness for organ donation by students and family members. Although there were no significant between-group differences in organ donor designation, the program seems to indirectly promote consent to organ donation by their families. © 2016 The Authors. Clinical Transplantation Published by John Wiley & Sons Ltd.

[Effect of nattokinase on restenosis after percutaneous transluminal angioplasty of the abdominal artery in rabbits].

PubMed

Gong, Min; Lin, Huan-bing; Wang, Qian; Xu, Jiang-ping

2008-08-01

To investigate the effect of nattokinase on intimal hyperplasia in rabbit abdominal artery after balloon injury and explore a novel strategy for the preventing restenosis after percutaneous transluminal angioplasty. Fifty-six New Zealand rabbits were randomly divided into 7 groups, namely the solvent control group, model group, natto extract lavage group, refined nattokinse lavage group, intravenous refined nattokinse injection group, clopidogrel group and clopidogrel-aspirin group. Balloon injury was induced by inserting the catheter through the femoral artery into the thoracic aorta of the rabbits. The platelet counts were notad and platelet aggregation was observed, and the abdominal artery was taken for pathological analysis. The expressions of MMP-2 and -9 in the abdominal artery were detected immunohistochemically. There was no significant difference in the platelet counts, platelet aggregation rate or MMP-2 and -9 expression between the model group and the nattokinse-treated groups (P>0.05). The stenosis index in each nattokinse-treated group was significantly greater and the neointimal proliferation index smaller than that of the model group (P<0.01 or 0.05). Nattokinse can inhibit restenosis of rabbit abdominal artery after percutaneous transluminal angioplasty, which is independent of its actions on the platelet or MMP-2 and -9 expressions.

Methylprednisolone therapy in deceased donors reduces inflammation in the donor liver and improves outcome after liver transplantation: a prospective randomized controlled trial.

PubMed

Kotsch, Katja; Ulrich, Frank; Reutzel-Selke, Anja; Pascher, Andreas; Faber, W; Warnick, P; Hoffman, S; Francuski, M; Kunert, C; Kuecuek, O; Schumacher, G; Wesslau, C; Lun, A; Kohler, S; Weiss, S; Tullius, S G; Neuhaus, P; Pratschke, Johann

2008-12-01

To investigate potential beneficial effects of donor treatment with methylprednisolone on organ function and outcome after liver transplantation. It is proven experimentally and clinically that the brain death of the donor leads to increased levels of inflammatory cytokines and is followed by an intensified ischemia/reperfusion injury after organ transplantation. In experiments, donor treatment with steroids successfully diminished these effects and led to better organ function after transplantation. To investigate whether methylprednisolone treatment of the deceased donor is applicable to attenuate brain death-associated damage in clinical liver transplantation we conducted a prospective randomized treatment-versus-control study in 100 deceased donors. Donor treatment (n = 50) consisted of 250 mg methylprednisolone at the time of consent for organ donation and a subsequent infusion of 100 mg/h until recovery of organs. A liver biopsy was taken immediately after laparotomy and blood samples were obtained after brain death diagnosis and before organ recovery. Cytokines were assessed by real-time reverse transcriptase-polymerase chain reaction. Soluble serum cytokines were measured by cytometric bead array system. After methylprednisolone treatment, steroid plasma levels were significantly higher (P < 0.05), and a significant decrease in soluble interleukins, monocyte chemotactic protein-1, interleukin-2, interleukin-6, tumor necrosis factor-alpha, and inducible protein-10 was observed. Methylprednisolone treatment resulted in a significant downregulation of intercellular adhesion molecule-1, tumor necrosis factor-alpha, major histocompatibility complex class II, Fas-ligand, inducible protein-10, and CD68 intragraft mRNA expression. Significantly ameliorated ischemia/reperfusion injury in the posttransplant course was accompanied by a decreased incidence of acute rejection. Our present study verifies the protective effect of methylprednisolone treatment in deceased donor liver transplantation, suggesting it as a potential therapeutical approach.

Platelet response to aspirin 50 and 100 mg in patients with coronary heart disease over a five-year period.

PubMed

Berent, Robert; Auer, Johann; Franklin, Barry; Schmid, Peter; von Duvillard, Serge P

2011-09-01

Aspirin has been shown to decrease cardiovascular (CV) events by ∼25%. Despite aspirin therapy 10% to 20% of patients with arterial vascular disease develop atherothrombotic events. A meta-analysis of antiplatelet therapy showed a progressive decrease in clinical efficacy of aspirin after 2 years. Whether this is due to a decreased sensitivity to aspirin during long-term therapy remains unclear. A prospective randomized clinical trial with serial monitoring over 5 years was conducted in 100 patients with documented coronary heart disease. We investigated whether long-term treatment with aspirin 50 and 100 mg affects platelet response similarly. Occurrence of CV events was documented. Platelet sensitivity to aspirin, prostacyclin, and adenosine diphosphate-, collagen-, and epinephrine-induced platelet aggregation were evaluated over time. In addition, β-thromboglobulin and inflammatory markers were measured. Four patients were lost to follow-up and 10 patients died. Eleven patients developed nonfatal CV events. In the 2 groups platelet response to aspirin and the referenced variables remained unchanged over 5 years. In patients who developed CV events, the last monitoring interval revealed no difference in platelet response to aspirin. However, patients with nonfatal and fatal CV events showed increased inflammatory markers versus patients without CV events independent of aspirin 50 or 100 mg intake. In conclusion, our study revealed no difference in antiplatelet response to aspirin 50 versus 100 mg or CV events over 5 years in patients with coronary heart disease. Copyright © 2011 Elsevier Inc. All rights reserved.

Transfusions of blood products and cancer outcomes.

PubMed

Velásquez, J F; Cata, J P

2015-10-01

Approximately half of cancer patients scheduled for major surgery are anemic. Also, a significant number of patients will present to the operating room with low platelet counts and coagulopathic disorders. Unfortunately, administration of red blood cells, platelets concentrates and fresh-frozen plasma is associated with unwanted adverse effects including fever, hemolytic reactions and transfusion-related immunomodulation (TRIM). TRIM is a multifactorial immunologic phenomenon in the recipient mediated by donor leukocytes, microparticles such as ectosomes, and growth factors. As some of these molecules are secreted in a time-dependent manner, blood storage time may play an important in TRIM, although the evidence is limited. Perioperative administration of red blood cells and associated TRIM has also been associated with increased recurrence of certain solid tumors, such as colorectal, lung, and hepatobiliary tumors. In this continuing education article, we review the available evidence on how perioperative blood product transfusions can affect oncological outcomes, such as cancer recurrence. Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

[Levels and molecular heterogeneity of serotonin transporter protein in platelets of patients with different mental diseases: a comparative analysis with the use of monoclonal and polyclonal antibodies].

PubMed

Brusov, O S; Faktor, M I; Zlobina, G P; Bologov, P V; Kaleda, V G; Oleĭchik, I V; Korenev, A N; Piatnitskiĭ, A N; Dupin, A M; Katasonov, A B; Morozova, M A; Beniashvili, A G; Lozier, R Kh; Pavlova, E V; Segal, O L; Massino, Iu S; Dmitriev, A D

2001-01-01

Polyclonal (PAb) and monoclonal (MAb) antibodies to CT2-epitope of the C-terminal fragment of serotonin transporter (SERT) protein were used to study the levels and molecular heterogeneity of platelet SERT in healthy donors and patients with affective (AD) and somatoform (SD) disorders, schizoaffective disorder (SAD) and schizophrenia. SERT was found to exist as high molecular wight (HMW) and low molecular weight (LMW) forms separated after electrophoresis. The levels of HMW and LMW forms of SERT were significantly, decreased in mentally ill patients as compared to healthy individuals. Unlike PAb, horse radish peroxidase (HRP)-conjugated MAbs were more sensitive and specific to SERT and could detect the LMW form of SERT as a duplet protein form with MW about 40 and 43 kDa. The MAb to CT2 C-terminal fragment of SERT conjugated with HRP is considered to be a new valuable tool for further investigation of SERT expression, properties, and posttranslation modification in the controls and in patients with different psychopathology.

Nitric oxide pathology and therapeutics in sickle cell disease.

PubMed

Kim-Shapiro, Daniel B; Gladwin, Mark T

2018-01-01

Sickle cell disease is caused by a mutant form of hemoglobin that polymerizes under hypoxic conditions which leads to red blood cell (RBC) distortion, calcium-influx mediated RBC dehydration, increased RBC adhesivity, reduced RBC deformability, increased RBC fragility, and hemolysis. These impairments in RBC structure and function result in multifaceted downstream pathology including inflammation, endothelial cell activation, platelet and leukocyte activation and adhesion, and thrombosis, all of which contribute vascular occlusion and substantial morbidity and mortality. Hemoglobin released upon RBC hemolysis scavenges nitric oxide (NO) and generates reactive oxygen species (ROS) and thereby decreases bioavailability of this important signaling molecule. As the endothelium-derived relaxing factor, NO acts as a vasodilator and also decreases platelet, leukocyte, and endothelial cell activation. Thus, low NO bioavailability contributes to pathology in sickle cell disease and its restoration could serve as an effective treatment. Despite its promise, clinical trials based on restoring NO bioavailability have so far been mainly disappointing. However, particular "NO donating" agents such as nitrite, which unlike some other NO donors can improve sickle RBC properties, may yet prove effective.

Application of platelet-rich plasma with stem cells in bone and periodontal tissue engineering

PubMed Central

Fernandes, Gabriela; Yang, Shuying

2016-01-01

Presently, there is a high paucity of bone grafts in the United States and worldwide. Regenerating bone is of prime concern due to the current demand of bone grafts and the increasing number of diseases causing bone loss. Autogenous bone is the present gold standard of bone regeneration. However, disadvantages like donor site morbidity and its decreased availability limit its use. Even allografts and synthetic grafting materials have their own limitations. As certain specific stem cells can be directed to differentiate into an osteoblastic lineage in the presence of growth factors (GFs), it makes stem cells the ideal agents for bone regeneration. Furthermore, platelet-rich plasma (PRP), which can be easily isolated from whole blood, is often used for bone regeneration, wound healing and bone defect repair. When stem cells are combined with PRP in the presence of GFs, they are able to promote osteogenesis. This review provides in-depth knowledge regarding the use of stem cells and PRP in vitro, in vivo and their application in clinical studies in the future. PMID:28018706

Platelet-rich fibrin matrix in the management of arthroscopic repair of the rotator cuff: a prospective, randomized, double-blinded study.

PubMed

Weber, Stephen C; Kauffman, Jeffrey I; Parise, Carol; Weber, Sophia J; Katz, Stephen D

2013-02-01

Arthroscopic rotator cuff repair has a high rate of patient satisfaction. However, multiple studies have shown significant rates of anatomic failure. Biological augmentation would seem to be a reasonable technique to improve clinical outcomes and healing rates. To represent a prospective, double-blinded, randomized study to assess the use of platelet-rich fibrin matrix (PRFM) in rotator cuff surgery. Randomized controlled trial; level of evidence, 1. Prestudy power analysis demonstrated that a sample size of 30 patients in each group (PRFM vs control) would allow recognition of a 20% difference in perioperative pain scores. Sixty consecutive patients were randomized to either receive a commercially available PRFM product or not. Preoperative and postoperative range of motion (ROM), University of California-Los Angeles (UCLA), and simple shoulder test (SST) scores were recorded. Surgery was performed using an arthroscopic single-row technique. Visual analog scale (VAS) pain scores were obtained upon arrival to the recovery room and 1 hour postoperatively, and narcotic consumption was recorded and converted to standard narcotic equivalents. The SST and ROM measurements were taken at 3, 6, 9, and 12 weeks postoperatively, and final (1 year) American shoulder and elbow surgeons (ASES) shoulder and UCLA shoulder scores were assessed. There were no complications. Randomization created comparable groups except that the PRFM group was younger than the control group (mean ± SD, 59.67 ± 8.16 y vs 64.50 ± 8.59 y, respectively; P < .05). Mean surgery time was longer for the PRFM group than for the control group (83.28 ± 17.13 min vs 73.28 ± 17.18 min, respectively; P < .02). There was no significant difference in VAS scores or narcotic use between groups and no statistically significant differences in recovery of motion, SST, or ASES scores. Mean ASES scores were 82.48 ± 8.77 (PRFM group) and 82.52 ± 12.45 (controls) (F(1,56) = 0.00, P > .98). Mean UCLA shoulder scores were 27.94 ± 4.98 for the PRFM group versus 29.59 ± 1.68 for the controls (P < .046). Structural results correlated with age and size of the tear and did not differ between the groups. Platelet-rich fibrin matrix was not shown to significantly improve perioperative morbidity, clinical outcomes, or structural integrity. While longer term follow-up or different platelet-rich plasma formulations may show differences, early follow-up does not show significant improvement in perioperative morbidity, structural integrity, or clinical outcome.

Efficacy of Platelet-Rich Fibrin After Mandibular Third Molar Extraction: A Systematic Review and Meta-Analysis.

PubMed

Al-Hamed, Faez Saleh; Tawfik, Mohamed Abdel-Monem; Abdelfadil, Ehab; Al-Saleh, Mohammed A Q

2017-06-01

To assess the effect of platelet-rich fibrin (PRF) on the healing process of the alveolar socket after surgical extraction of the mandibular third molars. PubMed, the Cochrane Central Register of Controlled Trials, Scopus, and relevant journals were searched using a combination of specific keywords ("platelet-rich fibrin," "oral surgery," and "third molar"). The final search was conducted on November 2, 2015. Randomized controlled clinical trials, as well as controlled clinical trials, aimed at comparing the effect of PRF versus natural healing after extraction of mandibular third molars were included. Five randomized controlled trials and one controlled clinical trial were included. There were 335 extractions (168 with PRF and 167 controls) in 183 participants. Considerable heterogeneity in study characteristics, outcome variables, and estimated scales was observed. Positive results were generally recorded for pain, trismus, swelling, periodontal pocket depth, soft tissue healing, and incidence of localized osteitis, but not in all studies. However, no meta-analysis could be conducted for such variables because of the different measurement scales used. The qualitative and meta-analysis results showed no significant improvement in bone healing with PRF-treated sockets compared with the naturally healing sockets. Within the limitations of the available evidence, PRF seems to have no beneficial role in bone healing after extraction of the mandibular third molars. Future standardized randomized controlled clinical trials are required to estimate the effect of PRF on socket regeneration. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Challenges in the management of the blood supply.

PubMed

Williamson, Lorna M; Devine, Dana V

2013-05-25

Although blood suppliers are seeing short-term reductions in blood demand as a result of initiatives in patient blood management, modelling suggests that during the next 5-10 years, blood availability in developed countries will need to increase again to meet the demands of ageing populations. Increasing of the blood supply raises many challenges; new approaches to recruitment and retainment of future generations of blood donors will be needed, and care will be necessary to avoid taking too much blood from these donors. Integrated approaches in blood stock management between transfusion services and hospitals will be important to minimise wastage--eg, by use of supply chain solutions from industry. Cross-disciplinary systems for patient blood management need to be developed to lessen the need for transfusion--eg, by early identification and reversal of anaemia with haematinics or by reversal of the underlying cause. Personalised medicine could be applied to match donors to patients, not only with extended blood typing, but also by using genetically determined storage characteristics of blood components. Growing of red cells or platelets in large quantities from stem cells is a possibility in the future, but challenges of cost, scaling up, and reproducibility remain to be solved. Copyright © 2013 Elsevier Ltd. All rights reserved.

Unrelated cord blood transplantation in children with severe congenital neutropenia.

PubMed

Yesilipek, M Akif; Tezcan, Gulsun; Germeshausen, Manuela; Kupesiz, Alphan; Uygun, Vedat; Hazar, Volkan

2009-09-01

SCN is an inherited hematological disorder with severe neutropenia and recurrent infections. Although there are some reports that recombinant rhG-CSF improves clinical outcome, allogeneic HSCT appears to be the only curative treatment for these patients. We report here two children with SCN successfully treated by CBT from unrelated donors. They were refractory to rhG-CSF treatment and have no identical family donor. Bu + CY were given as conditioning. Case 1 and Case 2 received 6/6 and 5/6 HLA-matched unrelated umbilical cord blood, respectively. The number of infused nucleated cells was 6, 18 x 10(7)/kg and CD34(+) cell number was 3, 74 x 10(5)/kg in Case 1. Those cell numbers were 8, 8 x 10(7)/kg and 5, 34 x 10(5)/kg for Case 2, respectively. Neutrophil/platelet engraftments were 45/49 days in Case 1 and 24/36 days in Case 2. Grade II cutaneous acute GVHD was seen in Case 2 that was treated successfully with prednisolone. Both patients are well with normal hematological findings and full donor chimerism for post-transplant 20 and 24 months, respectively. We conclude that UCB can be considered as a safe source of stem cell in patients with SCN who need urgent HSCT.

Demographic and epidemiologic characterization of transfusion recipients from four US regions: evidence from the REDS-III recipient database.

PubMed

Karafin, Matthew S; Bruhn, Roberta; Westlake, Matt; Sullivan, Marian T; Bialkowski, Walter; Edgren, Gustaf; Roubinian, Nareg H; Hauser, Ronald G; Kor, Daryl J; Fleischmann, Debra; Gottschall, Jerome L; Murphy, Edward L; Triulzi, Darrell J

2017-12-01

Blood transfusion is one of the most common medical procedures during hospitalization in the United States. To understand the benefits of transfusion while mitigating potential risks, a multicenter database containing detailed information on transfusion incidence and recipient outcomes would facilitate research. The Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) program has developed a comprehensive transfusion recipient database utilizing data from hospital electronic health records at 12 participating hospitals in four geographic regions. Inpatient and outpatient data on transfusion recipients from January 1, 2013 to December 31, 2014 included patient age, sex, ethnicity, primary diagnosis, type of blood product provided, issue location, pretransfusion and post-transfusion hemoglobin (Hgb), and hospital outcomes. Transfusion incidence per encounter was calculated by blood product and various patient characteristics. During the 2-year study period, 80,362 (12.5%) inpatient encounters involved transfusion. Among inpatients, the most commonly transfused blood products were red blood cells (RBCs; 10.9% of encounters), followed by platelets (3.2%) and plasma (2.9%). Among patients who received transfusions, the median number of RBC units was one, the pretransfusion Hgb level was 7.6 g/dL, and the Hgb increment per unit was 1.4 g/dL. Encounter mortality increased with patient age, the number of units transfused, and the use of platelet or plasma products. The most commonly reported transfusion reaction was febrile nonhemolytic. The database contains comprehensive data regarding transfusion use and patient outcomes. The current report describes an evaluation of the first 2 years of a planned, 4-year, linked blood donor-component-recipient database, which represents a critical new resource for transfusion medicine researchers. © 2017 AABB.

Haplo-identical transplantation for acquired severe aplastic anaemia in a multicentre prospective study.

PubMed

Xu, Lan-Ping; Wang, Shun-Qing; Wu, De-Pei; Wang, Jian-Min; Gao, Su-Jun; Jiang, Ming; Wang, Cun-Bang; Zhang, Xi; Liu, Qi-Fa; Xia, Ling-Hui; Wang, Xin; Huang, Xiao-Jun

2016-10-01

We conducted a prospective, multicentre study to confirm the feasibility of haplo-identical transplantation in treatment of severe aplastic anaemia (SAA) as salvage therapy, by analysing the outcomes of 101 patients who received haplo-identical transplantation between June 2012 and October 2015. All cases surviving for more than 28 d achieved donor myeloid engraftment. The median time for myeloid engraftment was 12 (range, 9-25) days and 15 (range, 7-101) days for platelets, with a cumulative platelet engraftment incidence of 94·1 ± 0·1%. With a median follow-up of 18·3 (3·0-43·6) months, recipients from haplo-identical transplantation had more cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD, 33·7% vs. 4·2%, P < 0·001), more chronic GVHD (22·4% vs. 6·6%, P = 0·014) at 1 year, but similar grade III-IV aGVHD (7·9% vs. 2·1%, P = 0·157), 3-year estimated overall survival (OS, 89·0% vs. 91·0%, P = 0·555) and failure-free survival (FFS, 86·8% vs. 80·3%, P = 0·659) when compared with 48 patients who received contemporaneous transplantation from matched related donors. Multivariate analysis showed no significant difference in engraftment and survival between the two cohorts. Both OS and FFS for the entire population correlated significantly with grades III-IV aGVHD. In conclusion, haplo-identical transplantation is a feasible choice for SAA with favourable outcomes. © 2016 John Wiley & Sons Ltd.

Correlation of platelet count and acute ST-elevation myocardial infarction.

PubMed

Paul, G K; Sen, B; Rahman, M Z; Ali, M; Rahman, M M; Rokonuzzaman, S M

2014-10-01

The study was conducted in the Department of cardiology, NICVD Dhaka during the period January 2006 to December 2007 to assess the impact of platelet on ST-elevation myocardial infarction (STEMI). To perform this prospective study 200 patients with STEMI within 72 hours of chest pain of both sexes were randomly selected and were evaluated by clinical history, physical examination and with the help of ECG, Echocardiography and others cardiac risk factors analysis. Heparin therapy before admission, previously documented thrombocytopenia (<140,000/cmm), history of previous or current haemostatic disorder, renal impairment (Creatinine >1.6mg/dl) and history of PCI & CABG were excluded in this study. Patient of Platelet count (PC) ≤200000/cubic millimeter (cmm) in Group I and patient of Group II, platelet counts were PC >200000/cmm. Follow up period was 3 days to 7 days after hospital admission. Primary outcome heart failure (any Killip class) was significantly more in Group II than Group I (40.0% vs. 23.0%; p=0.009). Though the incidence of Killip class I and cardiogenic shock were not significant between these two groups but Killip class II (18.0% vs. 8.0%; p=0.036) and Killip class III (15.0% vs. 6.0%; p=0.037) heart failure were significantly more among the patient with higher platelet counts. In-hospital mortality, one of the primary outcomes of this study, was significantly higher in Group II (13.0%) than Group I (5.0 %) and p value was 0.048. Re-infarction was more in patient with higher platelet counts group (Group II) than patients with lower platelet count (Group I) but statistically was not significant (16.0% vs.11.0%; p=0.300).

Meloxicam, 15 mg/day, spares platelet function in healthy volunteers.

PubMed

de Meijer, A; Vollaard, H; de Metz, M; Verbruggen, B; Thomas, C; Novakova, I

1999-10-01

To study the influence of meloxicam, a cyclooxygenase-2 (COX-2) preferential nonsteroidal anti-inflammatory drug, on serum thromboxane and platelet function in healthy volunteers with use of the maximum recommended daily dosage of 15 mg/day. This study used an open, randomized crossover design. Indomethacin (INN, indometacin) was given as a positive control for nonsteroidal anti-inflammatory drug-induced inhibition of platelet function. The following variables were recorded: thromboxane B2 serum concentrations by radioimmunoassay, platelet aggregation by whole blood aggregometry in response to collagen 1.1 microg/L and to arachidonic acid 0.35 mmol/L, and closure time with use of the PFA-100. Serum thromboxane B2 at baseline was 535+/-233 nmol/L (mean +/- SD) and was reduced for 95% by indomethacin to 26+/-19 nmol/L (P < .001) and for 66% by meloxicam to 183+/-62 nmol/L (P < .001). Maximal platelet aggregation in response to collagen at baseline was 18.7+/-1.6 ohms (ohms). It was reduced by indomethacin to 7.3+/-4.5 ohms (P < .001), but not by meloxicam (19+/-2.5 ohms). Platelet aggregation in response to arachidonic acid at baseline was 12.2+/-2.0 ohms. It was reduced by indomethacin in all subjects to 0 ohms, but not by meloxicam (11+/-2.4 ohms). Closure time at baseline was 128+/-24 seconds and was prolonged by indomethacin to 286+/-38 seconds (P < .001). Meloxicam caused a minor prolongation of the closure time (141+/-32 seconds; P < .05). Meloxicam, 15 mg/day caused a major reduction of maximum thromboxane production but no reduction in collagen- or arachidonic acid-induced platelet aggregation and only minor increase of the closure time.

Comparison of Prasugrel and Ticagrelor Antiplatelet Effects in Korean Patients Presenting With ST-Segment Elevation Myocardial Infarction.

PubMed

Lee, Young Seok; Jin, Cai De; Kim, Moo Hyun; Guo, Long Zhe; Cho, Young-Rak; Park, Kyungil; Park, Jong Sung; Park, Tae-Ho; Kim, Young Dae

2015-01-01

There is insufficient data on the efficacy of prasugrel and ticagrelor in Korean patients with ST-segment elevation myocardial infarction (STEMI). I n the current double-blind, prospective pilot study, 39 patients with STEMI undergoing primary percutaneous coronary intervention were randomized to receive prasugrel 60 mg loading dose (LD) followed by 10 mg daily maintenance dose (n=19), or ticagrelor 180 mg LD followed by 90 mg twice daily maintenance dose (n=20). We assessed platelet reactivity with the VerifyNow and Vasodilator-Stimulated Phosphoprotein (VASP) P2Y12 assays. Compared to baseline platelet reactivity, both prasugrel and ticagrelor groups achieved similar and significantly lower P2Y12 reaction units (PRU) (259 [IQR: 230 to 281] vs. 28 [12 to 55] for prasugrel; 261 [196 to 286] vs. 43 [11 to 61] for ticagrelor), and platelet reactivity indexes (PRI) (51.2% [39.3 to 61.3] vs. 8.1% [6.1 to 14.7] for prasugrel; 47.5% [38.4 to 50.4] vs. 11.2% [7.1 to 15.5] for ticagrelor, all P values <0.001) at 48 h post-LD. Most patients had low platelet reactivity with 95% PRU values <85 and 82% with PRI <16%. Both prasugrel and ticagrelor were effective for platelet inhibition in Korean STEMI patients with almost no patients exhibiting high platelet reactivity at 48 h after the LD. Our finding of a high number of patients with very low platelet reactivity deserves further studies to assess the safety of the drugs (Prasugrel and Ticagrelor in ST-segment Elevation Myocardial Infarction Study, NCT02075125).

[Antibacterial effect of autologous platelet-rich gel derived from health volunteers in vitro].

PubMed

Yang, Yanzhi; Liu, Hengchuan; Liu, Guanjian; Ran, Xingwu

2010-05-01

The use of autologous platelet-rich gel (APG) is a relatively new technology and a promising treatment method for infections, which is currently being used by a variety of surgical specialties. The mechanism of antibacterial effect of APG is not yet fully discovered. Subsequent evidence suggests that platelets have multiple functional attributes in antimicrobial host defense (including the capacity to generate antimicrobial oxygen metabolites and the antimicrobial peptides) and interact directly with microorganisms, contribute to clearance of pathogens from the blood. To investigate the bacteriostasis of APG against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa in vitro. Platelet-rich plasma (PRP) and platelet-poor plasma (PPP) were obtained from whole blood of 17 healthy donors. APG was prepared by mixing PRP with bovine thrombin in a 10% calcium gluconate solution or bovine thrombin in a 10% calcium gluconate solution and apocynin (APG-APO). Antibacterial effects of APG, PRP, and APG-APO on Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were evaluated by bacteriostasis assay. The culture results showed apparent decrease in the number of Staphylococcus aureus for both APG and APG-APO, which was maximal at first 4 hours and lasted to 24 hours and 8 hours, respectively; showing significant difference (P < 0.05) when compared APG with PRP and PPP, however no significant difference at first 8 hours (P > 0.05) and significant difference at 12 and 24 hours (P < 0.05) when compared APG with APG-APO; showing significant difference at first 4 hours (P < 0.05), no significant difference at 6, 8, 12, and 24 hours when compared APG-APO with PRP and PPP (P > 0.05). The bacteriostasis rates of APG and APG-APO were 27.36%-52.97% and 18.82%-51.52% against Escherichia coli, respectively; showing no significant difference (P > 0.05) when compared with PRP. The bacteriostasis rates of APG and APG-APO were less than 35% against Pseudomonas aeruginosa, showing no significant difference (P > 0.05) when compared with PRP; the bacteriostasis rates of PRP were less than 15% against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. APG may have potential bacteriostatic effect against Staphylococcus aureus by platelet mediating. Either APG or APG-APO has no obvious bacteriostatic effect against Escherichia coli or Pseudomonas aeruginosa. PRP has no antibacterial activity against Staphylococcus aureus, Escherichia coli or Pseudomonas aeruginosa.

Role of platelet-released growth factors in detoxification of reactive oxygen species in osteoblasts.

PubMed

Tohidnezhad, Mersedeh; Wruck, Christoph-Jan; Slowik, Alexander; Kweider, Nisreen; Beckmann, Rainer; Bayer, Andreas; Houben, Astrid; Brandenburg, Lars-Ove; Varoga, Deike; Sönmez, Tolga-Taha; Stoffel, Marcus; Jahr, Holger; Lippross, Sebastian; Pufe, Thomas

2014-08-01

Oxidative stress can impair fracture healing. To protect against oxidative damage, a system of detoxifying and antioxidative enzymes works to reduce the cellular stress. The transcription of these enzymes is regulated by antioxidant response element (ARE). The nuclear factor (erythroid-derived 2)-like2 (Nrf2) plays a major role in transcriptional activation of ARE-driven genes. Recently it has been shown that vascular endothelial growth factor (VEGF) prevents oxidative damage via activation of the Nrf2 pathway in vitro. Platelet-released growth factor (PRGF) is a mixture of autologous proteins and growth factors, prepared from a determined volume of platelet-rich plasma (PRP). It has already used to enhance fracture healing in vitro. The aim of the present study was to elucidate if platelets can lead to upregulation of VEGF and if platelets can regulate the activity of Nrf2-ARE system in primary human osteoblast (hOB) and in osteoblast-like cell line (SAOS-2). Platelets and PRGF were obtained from healthy human donors. HOB and SAOS-2 osteosarcoma cell line were used. The ARE activity was analysed using a dual luciferase reporter assay system. We used Western blot to detect the nuclear accumulation of Nrf2 and the amount of cytosolic antioxidant Thioredoxin Reductase-1 (TXNRD-1), Heme Oxygenase-1 (HO-1) and NAD(P)H quinine oxidoreductase-1 (NQO1). Gene expression analysis was performed by real-time RT PCR. ELISA was used for the quantification of growth factors. The activity of ARE was increased in the presence of PRGF up to 50%. Western blotting demonstrated enhanced nuclear accumulation of Nrf2. This was followed by an increase in the protein expression of the aforementioned downstream targets of Nrf2. Real-time RT PCR data showed an upregulation in the gene expression of the VEGF after PRGF treatment. This was confirmed by ELISA, where the treatment with PRGF induced the protein level of VEGF in both cells. These results provide a new insight into PRGF's mode of action in osteoblasts. PRGF not only leads to increase the endogenous VEGF, but also it may be involved in preventing oxidative damage through the Nrf2-ARE signalling. Nrf2 activation via PRGF may have great potential as an effective therapeutic drug target in fracture healing. Copyright © 2014 Elsevier Inc. All rights reserved.

Transfusion-Transmitted Hepatitis E: NAT Screening of Blood Donations and Infectious Dose.

PubMed

Dreier, Jens; Knabbe, Cornelius; Vollmer, Tanja

2018-01-01

The risk and importance of transfusion-transmitted hepatitis E virus (TT-HEV) infections by contaminated blood products is currently a controversial discussed topic in transfusion medicine. The infectious dose, in particular, remains an unknown quantity. In the present study, we illuminate and review this aspect seen from the viewpoint of a blood donation service with more than 2 years of experience in routine HEV blood donor screening. We systematically review the actual status of presently known cases of TT-HEV infections and available routine NAT-screening assays. The review of the literature revealed a significant variation regarding the infectious dose causing hepatitis E. We also present the outcome of six cases confronted with HEV-contaminated blood products, identified by routine HEV RNA screening of minipools using the highly sensitive RealStar HEV RT-PCR Kit (95% LOD: 4.7 IU/mL). Finally, the distribution of viral RNA in different blood components [plasma, red blood cell concentrate (RBC), platelet concentrates (PC)] was quantified using the first WHO international standard for HEV RNA for NAT-based assays. None of the six patients receiving an HEV-contaminated blood product from five different donors (donor 1: RBC, donor 2-5: APC) developed an acute hepatitis E infection, most likely due to low viral load in donor plasma (<100 IU/mL). Of note, the distribution of viral RNA in blood components depends on the plasma content of the component; nonetheless, HEV RNA could be detected in RBCs even when low viral plasma loads of 100-1,000 IU/mL are present. Comprehensive retrospective studies of TT-HEV infection offered further insights into the infectivity of HEV RNA-positive blood products. Minipool HEV NAT screening (96 samples) of blood donations should be adequate as a routine screening assay to identify high viremic donors and will cover at least a large part of viremic phases.

Effects of clopidogrel and aspirin combination versus aspirin alone on platelet aggregation and major receptor expression in patients with heart failure: the Plavix Use for Treatment Of Congestive Heart Failure (PLUTO-CHF) trial.

PubMed

Serebruany, Victor L; Malinin, Alex I; Jerome, Scott D; Lowry, David R; Morgan, Athol W; Sane, David C; Tanguay, Jean-François; Steinhubl, Steven R; O'connor, Christopher M

2003-10-01

Persistent platelet activation may contribute to thrombotic events in patients with congestive heart failure (CHF). Chronic use of mild platelet inhibitors could therefore represent an independent avenue to improve morbidity, mortality, and quality of life in this expanding population. Although clopidogrel is widely used in patients with acute coronary syndromes and ischemic stroke, the ability of this novel ADP-receptor antagonist to inhibit platelet function in patients with CHF is unknown. We assessed antiplatelet properties of clopidogrel with aspirin (C+A) versus aspirin alone (A) in patients with CHF with heightened platelet activity. Patients with left ventricular ejection fraction <40%, or CHF symptoms in the setting of preserved systolic function and New York Heart Association class II-IV were screened. Patients were considered to have platelet activation when 4 of the following 5 parameters were met: ADP-induced platelet aggregation >60%; collagen-induced aggregation >70%; whole blood aggregation >18 ohms; expression of GP IIb/IIIa >220 log MFI; and P-selectin cell positivity >8%. All patients were treated with 325 mg of acetylsalycilic acid (ASA) for at least 1 month. Patients receiving an antithrombotic agent other than ASA were excluded. Patients meeting clinical and laboratory criteria were randomly assigned to C+A (n=25), A (n=25) groups, or represent screen failures (n=38). Platelet studies (conventional and whole blood aggregometry, shear-induced activation, expression of 10 major receptors and formation of platelet-leukocyte microparticles) were performed at baseline and after 30 days of therapy. There were no deaths, hospitalizations, or serious adverse events. There were no changes in platelet parameters in the A group. In contrast, therapy with C+A resulted in a significant inhibition of platelet activity assessed by ADP-induced (P =.00001), and epinephrine-induced (P =.0016) aggregation, closure time (P =.04), expression of PECAM-1 (P =.009), GP Ib (P =.006), GP IIb/IIIa antigen (P =.0001), GP IIb/IIIa activity with PAC-1 (P =.0021), and CD151 (P =.0026) when compared with the A group. Therapy with C+A also resulted in the reduced formation of platelet-leukocyte microparticles (P =.021). Collagen-induced aggregation in plasma and in whole blood, expression of vitronectin receptor, P-selectin, CD63, CD107a, and CD107b did not differ among groups. Treatment with C+A for 1 month provides significantly greater inhibition of platelet activity than ASA alone in patients with CHF. Patients with CHF with heightened platelet activity represent a potential target population in which addition of clopidogrel may decrease mortality rates by reducing the incidence of thrombotic vascular events.

Treatment of Subacromial Impingement Syndrome: Platelet-Rich Plasma or Exercise Therapy? A Randomized Controlled Trial.

PubMed

Nejati, Parisa; Ghahremaninia, Armita; Naderi, Farrokh; Gharibzadeh, Safoora; Mazaherinezhad, Ali

2017-05-01

Subacromial impingement syndrome (SAIS) is the most common disorder of the shoulder. The evidence for the effectiveness of treatment options is inconclusive and limited. Therefore, there is a need for more evidence in this regard, particularly for long-term outcomes. Platelet-rich plasma (PRP) would be an effective method in treating subacromial impingement. Randomized controlled trial; Level of evidence, 1. This was a single-blinded randomized clinical trial with 1-, 3-, and 6-month follow-up. Sixty-two patients were randomly placed into 2 groups, receiving either PRP or exercise therapy. The outcome parameters were pain, shoulder range of motion (ROM), muscle force, functionality, and magnetic resonance imaging findings. Both treatment options significantly reduced pain and increased shoulder ROM compared with baseline measurements. Both treatments also significantly improved functionality. However, the treatment choices were not significantly effective in improving muscle force. Trend analysis revealed that in the first and third months, exercise therapy was superior to PRP in pain, shoulder flexion and abduction, and functionality. However, in the sixth month, only shoulder abduction and total Western Ontario Rotator Cuff score were significantly different between the 2 groups. Both PRP injection and exercise therapy were effective in reducing pain and disability in patients with SAIS, with exercise therapy proving more effective.

Implementation Intentions as a Strategy to Increase the Notification Rate of Potential Ocular Tissue Donors by Nurses: A Clustered Randomized Trial in Hospital Settings

PubMed Central

2014-01-01

Aim. The purpose of this study is to evaluate the impact, among nurses in hospital settings, of a questionnaire-based implementation intentions intervention on notification of potential ocular tissue donors to donation stakeholders. Methods. This randomized intervention was clustered at the level of hospital departments with two study arms: questionnaire-based implementation intentions intervention and control. In the intervention group, nurses were asked to plan specific actions if faced with a number of barriers when reporting potential ocular donors. The primary outcome was the potential ocular tissue donors' notification rate before and after the intervention. Analysis was based on a generalized linear model with an identity link and a binomial distribution. Results. We compared outcomes in 26 departments from 5 hospitals, 13 departments per condition. The implementation intentions intervention did not significantly increase the notification rate of ocular tissue donors (intervention: 23.1% versus control: 21.1%; χ 2 = 1.14, 2; P = 0.56). Conclusion. A single and brief implementation intentions intervention among nurses did not modify the notification rate of potential ocular tissue donors to donation stakeholders. Low exposure to the intervention was a major challenge in this study. Further studies should carefully consider a multicomponent intervention to increase exposure to this type of intervention. PMID:25132990

Cell activation and cellular-cellular interactions during hemodialysis: effect of dialyzer membrane.

PubMed

Sirolli, V; Ballone, E; Di Stante, S; Amoroso, L; Bonomini, M

2002-06-01

During hemodialysis (HD), circulating blood cells can be activated and also engage in dynamic interplay. These phenomena may be important factors behind dialysis membrane bio(in)compatibility. In the present prospective cross-over study, we have used flow cytometry to evaluate the influence of different dialysis membranes on the activation of circulating blood cells (leukocytes, platelets) and their dynamic interactions (formation of circulating platelet-leukocyte and platelet-erythrocyte aggregates) during in vivo HD. Each patient (n = 10) was treated with dialyzers containing membranes of cellulose diacetate, polysulfone and ethylenevinylalcohol (EVAL) in a randomized order. Upregulation of adhesion receptor expression (CD15s, CD11b/CD18) occurred mainly with the cellulosic membrane, though an increase in CD11b/CD18 circulating on neutrophils was also found with both synthetic membranes. Circulating activated platelets (P-selectin/CD63-positive platelets) increased during HD sessions with cellulose diacetate and polysulfone. An increased formation of platelet-neutrophil aggregates was found at 15 and 30 min during dialysis with cellulose diacetate and polysulfone but not with EVAL. Platelet-erythrocyte aggregates also increased with cellulose diacetate and at 15 min with polysulfone as well. Generally in concomitance with the increase in platelet-neutrophil coaggregates, there was an increased hydrogen peroxide production by neutrophils. The results of this study indicate that cellular mechanisms can be activated during HD largely depending on the membrane material, EVAL causing less reactivity than the other two membranes. It appears that each dialysis membrane has multiple and different characteristics that may contribute to interactions with blood components. Our results also indicate that derivatizing cellulose (cellulose diacetate) may be a useful way to improve the biocompatibility of the cellulose polymer and that there may be great variability in the biocompatibility profile of synthetic membranes, dialysis with polysulfone being in general associated with a higher degree of cell activation than EVAL membrane.

Influence of HbA1c levels on platelet function profiles associated with tight glycemic control in patients presenting with hyperglycemia and an acute coronary syndrome. A subanalysis of the CHIPS Study ("Control de HIperglucemia y Actividad Plaquetaria en Pacientes con Síndrome Coronario Agudo").

PubMed

Vivas, David; García-Rubira, Juan C; Bernardo, Esther; Angiolillo, Dominick J; Martín, Patricia; Calle-Pascual, Alfonso; Núñez-Gil, Iván; Macaya, Carlos; Fernández-Ortiz, Antonio

2013-02-01

Patients with hyperglycemia, an acute coronary syndrome and poor glycemic control have increased platelet reactivity and poor prognosis. However, it is unclear the influence of a tight glycemic control on platelet reactivity in these patients. This is a subanalysis of the CHIPS study. This trial randomized patients with hyperglycemia to undergo an intensive glucose control (target blood glucose 80-120 mg/dL), or conventional glucose control (target blood glucose <180 mg/dL). We analyzed platelet function at discharge on the subgroup of patients with poor glycemic control, defined with admission levels of HbA1c higher than 6.5%. The primary endpoint was maximal platelet aggregation following stimuli with 20 μM ADP. We also measured aggregation following collagen, epinephrine, and thrombin receptor-activated peptide, as well as P2Y12 reactivity index and surface expression of glycoprotein IIb/IIIa and P-selectin. A total of 67 patients presented HbA1c ≥ 6.5% (37 intensive, 30 conventional), while 42 had HbA1c < 6.5% (20 intensive, 22 conventional). There were no differences in baseline characteristics between groups. At discharge, patients with HbA1c ≥6.5% had significantly reduced MPA with intensive glucose control compared with conventional control (46.1 ± 22.3 vs. 60.4 ± 20.0%; p = 0.004). Similar findings were shown with other measures of platelet function. However, glucose control strategy did not affect platelet function parameters in patients with HbA1c < 6.5%. Intensive glucose control in patients presenting with an acute coronary syndrome and hyperglycemia results in a reduction of platelet reactivity only in the presence of elevated HbA1c levels.

The Effect of a Simulated Commercial Flight Environment with Hypoxia and Low Humidity on Clotting, Platelet, and Endothelial Function in Participants with Type 2 Diabetes - A Cross-over Study.

PubMed

Konya, Judit; Al Qaissi, Ahmed; Sathyapalan, Thozhukat; Ajjan, Ramzi; Madden, Leigh; Naseem, Khalid M; Garrett, Andrew Thomas; Kilpatrick, Eric; Atkin, Stephen L

2018-01-01

To determine if clotting, platelet, and endothelial function were affected by simulated short-haul commercial air flight conditions (SF) in participants with type 2 diabetes (T2DM) compared to controls. 10 participants with T2DM (7 females, 3 males) and 10 controls (3 females, 7 males) completed the study. Participants were randomized to either spend 2 h in an environmental chamber at sea level conditions (temperature: 23°C, oxygen concentration 21%, humidity 45%), or subject to a simulated 2-h simulated flight (SF: temperature: 23°C, oxygen concentration 15%, humidity 15%), and crossed over 7 days later. Main outcome measures: clot formation and clot lysis parameters, functional platelet activation markers, and endothelial function measured by reactive hyperemia index (RHI) by EndoPAT and serum microparticles. Comparing baseline with SF conditions, clot maximal absorption was increased in controls (0.375 ± 0.05 vs. 0.39 ± 0.05, p  < 0.05) and participants with T2DM (0.378 ± 0.089 vs. 0.397 ± 0.089, p  < 0.01), while increased basal platelet activation for both fibrinogen binding and P-selectin expression ( p  < 0.05) was seen in participants with T2DM. Parameters of clot formation and clot lysis, stimulated platelet function (stimulated platelet response to ADP and sensitivity to prostacyclin), and endothelial function were unchanged. While SF resulted in the potential of denser clot formation with enhanced basal platelet activation in T2DM, the dynamic clotting, platelet, and endothelial markers were not affected, suggesting that short-haul commercial flying adds no additional hazard for venous thromboembolism for participants with T2DM compared to controls.

Graft Transit Time Has No Effect on Outcome of Unrelated Donor Hematopoietic Cell Transplants Performed in Australia and New Zealand: A Study from the Australasian Bone Marrow Transplant Recipient Registry.

PubMed

Patton, William Nigel; Nivison-Smith, Ian; Bardy, Peter; Dodds, Anthony; Ma, David; Shaw, Peter John; Kwan, John; Wilcox, Leonie; Butler, Andrew; Carter, John M; Blacklock, Hilary; Szer, Jeffrey

2017-01-01

A previous study found that platelet recovery and mortality were worse in recipients of myeloablative bone marrow transplants where graft transit times were longer than 20 hours. This retrospective study of unrelated myeloablative allogeneic transplantation performed within Australia and New Zealand analyzed transplant outcomes according to graft transit times. Of 233 assessable cases, 76 grafts (33%) were sourced from bone marrow (BM) and 157 (67%) from peripheral blood. Grafts sourced from Australia and New Zealand (47% of total) were associated with a median transit time of 6 hours versus 32 hours for overseas sourced grafts (53% of total). Graft transit temperature was refrigerated in 85%, ambient in 6%, and unknown in 9% of cases, respectively. Graft transit times had no significant effect on neutrophil or platelet engraftment, treatment-related mortality, overall survival, and incidence of acute or chronic graft-versus-host disease. Separate analysis of BM grafts, although of reduced power, also showed no significant difference in either neutrophil or platelet engraftment or survival between short and longer transport times. This study gives reassurance that both peripheral blood stem cell and especially BM grafts subjected to long transit times and transported at refrigerated temperatures may not be associated with adverse recipient outcomes. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Type I Glanzmann thrombasthenia caused by an apparently silent beta3 mutation that results in aberrant splicing and reduced beta3 mRNA.

PubMed

Xie, Jingli; Pabón, Dina; Jayo, Asier; Butta, Nora; González-Manchón, Consuelo

2005-05-01

We report a novel genetic defect in a patient with type I Glanzmann thrombasthenia. Flow cytometry analysis revealed undetectable levels of platelet glycoproteins alphaIIb and beta3, although residual amounts of both proteins were detectable in immunoblotting analysis. Sequence analysis of reversely transcribed platelet beta3 mRNA showed a 100-base pair deletion in the 3'-boundary of exon 11, that results in a frame shift and appearance of a premature STOP codon. Analysis of the corresponding genomic DNA fragment revealed the presence of a homozygous C1815T transition in exon 11. The mutation does not change the amino acid residue but it creates an ectopic consensus splice donor site that is used preferentially, causing splicing out of part of exon 11. The parents of the proband, heterozygous for this mutation, were asymptomatic and had reduced platelet content of alphaIIbbeta3. PCR-based relative quantification of beta3 mRNA failed to detect the mutant transcript in the parents and showed a marked reduction in the patient. The results suggest that the thrombasthenic phenotype is, mainly, the result of the reduced availability of beta3-mRNA, most probably due to activation of the nonsense-mediated mRNA decay mechanism. They also show the convenience of analyzing both genomic DNA and mRNA, in order to ascertain the functional consequences of single nucleotide substitutions.

Phospholipid-esterified eicosanoids are generated in agonist-activated human platelets and enhance tissue factor-dependent thrombin generation.

PubMed

Thomas, Christopher P; Morgan, Lloyd T; Maskrey, Benjamin H; Murphy, Robert C; Kühn, Hartmut; Hazen, Stanley L; Goodall, Alison H; Hamali, Hassan A; Collins, Peter W; O'Donnell, Valerie B

2010-03-05

Here, a group of specific lipids, comprising phosphatidylethanolamine (PE)- or phosphatidylcholine (PC)-esterified 12S-hydroxyeicosatetraenoic acid (12S-HETE), generated by 12-lipoxygenase was identified and characterized. 12S-HETE-PE/PCs were formed within 5 min of activation by thrombin, ionophore, or collagen. Esterified HETE levels generated in response to thrombin were 5.85 +/- 1.42 (PE) or 18.35 +/- 4.61 (PC), whereas free was 65.5 +/- 17.6 ng/4 x 10(7) cells (n = 5 separate donors, mean +/- S.E.). Their generation was stimulated by triggering protease-activated receptors-1 and -4 and signaling via Ca(2+) mobilization secretory phospholipase A2, platelet-activating factor-acetylhydrolase, src tyrosine kinases, and protein kinase C. Stable isotope labeling showed that they form predominantly by esterification that occurs on the same time scale as free acid generation. Unlike free 12S-HETE that is secreted, esterified HETEs remain cell-associated, with HETE-PEs migrating to the outside of the plasma membrane. 12-Lipoxygenase inhibition attenuated externalization of native PE and phosphatidylserine and HETE-PEs. Platelets from a patient with the bleeding disorder, Scott syndrome, did not externalize HETE-PEs, and liposomes supplemented with HETE-PC dose-dependently enhanced tissue factor-dependent thrombin generation in vitro. This suggests a role for these novel lipids in promoting coagulation. Thus, oxidized phospholipids form by receptor/agonist mechanisms, not merely as an undesirable consequence of vascular and inflammatory disease.

Chin Symphysis Bone, Allograft, and Platelet-Rich Fibrin: Is the Combination Effective in Repair of Alveolar Cleft?

PubMed

Movahedian Attar, Bijan; Naghdi, Navid; Etemadi Sh, Milad; Mehdizadeh, Mojdeh

2017-05-01

Secondary grafting of alveolar defects with iliac crest bone is a common treatment method in cleft patients. The aim of this study was to evaluate the effectiveness of the combination of symphysis bone, allograft, and platelet-rich fibrin in regeneration of alveolar defects compared with iliac bone graft. In this randomized clinical trial, patients with unilateral alveolar defects were divided randomly into two categories. Group A comprised patients in whom the combination of chin symphysis bone plus allogeneic bone material plus leukocyte- and platelet-rich fibrin was considered for treatment. Group B comprised patients in whom iliac bone graft was considered. Cone beam computed tomography before treatment and 1 year postoperatively was used for measurement of bone formation (bone volume in cubic centimeters). The data were analyzed by paired t and χ 2 tests via SPSS software (version 23; IBM, Armonk, NY). P < .05 was considered significant. Each group included 10 patients (with 6 male patients in group A and 5 male patients in group B). The mean age of patients in groups A and B was 9.5 ± 1.5 years and 9.9 ± 1.9 years, respectively. The mean volume of alveolar defects was 0.89 ± 0.29 cm 3 in group A and 0.95 ± 0.27 cm 3 in group B. The percentage of bone regeneration in groups A and B was 69.5% and 73.8%, respectively. It seems that chin symphysis bone plus allogeneic bone material plus platelet-rich fibrin is a proper combination for bone regeneration in alveolar defects with a small to moderate volume range. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Effect of aliskiren and valsartan combination versus aliskiren monotherapy on hemostatic biomarkers in hypertensive diabetics: Aliskiren and Valsartan Impact in Diabetics pilot trial.

PubMed

Serebruany, Victor L; Pokov, Alex N; Aradi, Daniel; Can, Mehmet; DiNicolantonio, James; Kipshidze, Nodar; Atar, Dan

2014-01-01

Valsartan is known to inhibit platelet activity in both in vitro and ex vivo clinical setting, whereas aliskiren in vitro modulates antithrombin-III in plasma. The authors tested how aliskiren and valsartan combination versus aliskiren monotherapy will affect hemostatic biomarkers in mild-to-moderate hypertensive diabetics in the frame of the Aliskiren and Valsartan Impact in Diabetics (AVID) trial. A total of 52 patients with type 2 diabetes and mild-to-moderate hypertension were equally randomized to aliskiren (150-300 mg/d) and valsartan (160 mg/d) versus aliskiren (150-300 mg/d) alone for 4 weeks. A total of 25 biomarkers were serially measured, of which 16 are related to platelet function, 6 to coagulation, and 3 to fibrinolysis. Aliskiren monotherapy has no significant impact on any of the assessed biomarkers. In contrast, valsartan on top of aliskiren provided significant inhibition of ADP-induced platelet aggregation (P=0.032), decreased shear-induced activation measured with PFA-100 analyzer (P=0.041), and diminished expression of GP IIb/IIIa activity (P=0.027) measured by PAC-1 antibody, GP Ib (CD42b, P=0.033), vitronectin receptor (CD51/61, P=0.046), P-selectin (CD62p, P=0.026), lysosome-associated membrane protein (CD107a, P=0.042), and CD40-ligand (CD154, P=0.048). In AVID trial, valsartan in combination with aliskiren mildly but significantly inhibited platelets, confirming previous observations. In contrast, aliskiren monotherapy does not enhance antithrombin activity, suggesting that previous data probably represent a laboratory artifact. Importantly, these randomized data were generated on top of low-dose daily aspirin, supporting extra benefit for combination use of angiotensin receptor blockers and renin inhibitors in high-risk diabetic population.

Effects of pre-transplant azithromycin administration on kidney graft function: study protocol for a double-blind randomized clinical trial.

PubMed

Mokhtari, Gholamreza; Teimoori, Mojtaba

2018-06-28

Kidney transplantation is the best strategy for the management of end-stage renal disease; however, the outcomes need to improve further. Macrolides show antimicrobial and anti-inflammatory properties in chronic diseases and intraoperatively, and can accumulate in tissues for extended periods. Therefore, theoretically, when administered to a donor and because of accumulation in the donor kidney, macrolides can cause graft immunomodulation and improve kidney transplantation outcomes. This study is a single-center, randomized clinical trial. A total of 60 kidney donors will be randomly allocated to the azithromycin or placebo group and treated with a single dose (1 g) of azithromycin or placebo, respectively, 1 day before surgery. Recruitment commenced in September 2016 and is expected to be completed by March 2018. The primary outcome is kidney graft function. The secondary outcomes include rejection rate, urinary tract infections in graft recipients, pain and systemic inflammatory response syndrome in live donors, and complications in both donors and recipients. Outcomes will be evaluated at baseline and every day in the first week after transplantation, as well as at 1 and 3 months post transplantation. Adverse reactions will be documented. If the efficacy of azithromycin in reducing adverse outcomes is confirmed, it would serve as an easy to use, economic intervention able to lower post-transplantation risks. Short and mid-term analyses of blood and urine samples as well as immunological assays will facilitate a more in-depth analysis of the effects of azithromycin on transplantation outcomes. Iranian Clinical Trial Registry, IRCT201606141853N11 , registered on September 5, 2016.

Effect of low-level laser therapy on the healing process of donor site in patients with grade 3 burn ulcer after skin graft surgery (a randomized clinical trial).

PubMed

Vaghardoost, Reza; Momeni, Mahnoush; Kazemikhoo, Nooshafarin; Mokmeli, Soheila; Dahmardehei, Mostafa; Ansari, Fereshteh; Nilforoushzadeh, Mohammad Ali; Sabr Joo, Parisa; Mey Abadi, Sara; Naderi Gharagheshlagh, Soheila; Sassani, Saeed

2018-04-01

Skin graft is a standard therapeutic technique in patients with deep ulcers, but managing donor site after grafting is very important. Although several modern dressings are available to enhance the comfort of donor site, using techniques that accelerate wound healing may enhance patient satisfaction. Low-level laser therapy (LLLT) has been used in several medical fields, including healing of diabetic, surgical, and pressure ulcers, but there is not any report of using this method for healing of donor site in burn patients. The protocols and informed consent were reviewed according to Medical Ethics Board of Shahid Beheshti University of Medical Sciences (IR.SBMU.REC.1394.363) and Iranian Registry of Clinical Trials (IRCT2016020226069N2). Eighteen donor sites in 11 patients with grade 3 burn ulcer were selected. Donor areas were divided into 2 parts, for laser irradiation and control randomly. Laser area was irradiated by a red, 655-nm laser light, 150 mW, 2 J/cm 2 , on days 0 (immediately after surgery), 3, 5, and 7. Dressing and other therapeutic care for both sites were the same. The patients and the person who analyzed the results were blinded. The size of donor site reduced in both groups during the 7-day study period (P < 0.01) and this reduction was significantly greater in the laser group (P = 0.01). In the present study, for the first time, we evaluate the effects of LLLT on the healing process of donor site in burn patients. The results showed that local irradiation of red laser accelerates wound healing process significantly.

Assessment of effects of phenolic fractions from leaves and petals of dandelion in selected components of hemostasis.

PubMed

Lis, Bernadetta; Jędrejek, Dariusz; Stochmal, Anna; Olas, Beata

2018-05-01

Aerial parts and roots of Taraxacum officinale (dandelion) have been found to be rich sources of polyphenols, including cinnamic acid derivatives, flavonoids and triterpenoids, which exert different biological activities, such as anti-inflammatory, anticancer and antimicrobial. Additionally, the whole plant is recognized as safe and well tolerated by humans, with no reported adverse effects. Nowadays, dandelion is a commonly available dietary supplement and a component of pharmaceutical preparations used for the treatment of bladder, liver, and spleen. Nevertheless, the effect of dandelion on blood platelets and plasma - components of hemostasis involved in the functioning of a cardiovascular system and linked with various cardiovascular diseases, has not been studied yet. Thus, the main objective of our in vitro experiments was to examine the anti-platelet and antioxidant properties of four standardized dandelion phenolic fractions, i.e. leaves 50% and 85% methanol fractions, and petals 50% and 85% methanol fractions, in blood platelets. Additionally, aforementioned plant preparations were investigated for hemostatic activity in plasma, using three selected hemostatic parameters: the activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT). None of the studied dandelion fractions, caused the damage of human blood platelets, at the whole tested range. The inhibition of lipid peroxidation in platelets treated with H 2 O 2 /Fe (the donor of OH) was observed for two fractions: leaves and petals 50% fractions, both at the dose 50 μg/mL. Analysis of the effect on the coagulation activity of human plasma demonstrated that three fractions: petals 50% fraction, and leaves and petals 85% fractions, significantly prolonged the thrombin time, at the whole tested range. On the contrary, none of the fractions changed the APTT and the PT. The obtained results demonstrate that dandelion preparations, based on aerial parts, especially rich in hydroxycinnamic acid derivatives (leaves and petals 50% fractions) are promising plant materials exerting both antioxidant and anticoagulant activities of the hemostatic system that is beneficial in the prevention and treatment of cardiovascular diseases. Published by Elsevier Ltd.

The duplication mutation of Quebec platelet disorder dysregulates PLAU, but not C10orf55, selectively increasing production of normal PLAU transcripts by megakaryocytes but not granulocytes.

PubMed

Hayward, Catherine P M; Liang, Minggao; Tasneem, Subia; Soomro, Asim; Waye, John S; Paterson, Andrew D; Rivard, Georges E; Wilson, Michael D

2017-01-01

Quebec Platelet disorder (QPD) is a unique bleeding disorder that markedly increases urokinase plasminogen activator (uPA) in megakaryocytes and platelets but not in plasma or urine. The cause is tandem duplication of a 78 kb region of chromosome 10 containing PLAU (the uPA gene) and C10orf55, a gene of unknown function. QPD increases uPA in platelets and megakaryocytes >100 fold, far more than expected for a gene duplication. To investigate the tissue-specific effect that PLAU duplication has on gene expression and transcript structure in QPD, we tested if QPD leads to: 1) overexpression of normal or unique PLAU transcripts; 2) increased uPA in leukocytes; 3) altered levels of C10orf55 mRNA and/or protein in megakaryocytes and leukocytes; and 4) global changes in megakaryocyte gene expression. Primary cells and cultured megakaryocytes from donors were prepared for quantitative reverse polymerase chain reaction analyses, RNA-seq and protein expression analyses. Rapidly isolated blood leukocytes from QPD subjects showed only a 3.9 fold increase in PLAU transcript levels, in keeping with the normal to minimally increased uPA in affinity purified, QPD leukocytes. All subjects had more uPA in granulocytes than monocytes and minimal uPA in lymphocytes. QPD leukocytes expressed PLAU alleles in proportions consistent with an extra copy of PLAU on the disease chromosome, unlike QPD megakaryocytes. QPD PLAU transcripts were consistent with reference gene models, with a much higher proportion of reads originating from the disease chromosome in megakaryocytes than granulocytes. QPD and control megakaryocytes contained minimal reads for C10orf55, and C10orf55 protein was not increased in QPD megakaryocytes or platelets. Finally, our QPD megakaryocyte transcriptome analysis revealed a global down regulation of the interferon type 1 pathway. We suggest that the low endogenous levels of uPA in blood are actively regulated, and that the regulatory mechanisms are disrupted in QPD in a megakaryocyte-specific manner.

The duplication mutation of Quebec platelet disorder dysregulates PLAU, but not C10orf55, selectively increasing production of normal PLAU transcripts by megakaryocytes but not granulocytes

PubMed Central

Soomro, Asim; Waye, John S.; Paterson, Andrew D.; Rivard, Georges E.; Wilson, Michael D.

2017-01-01

Quebec Platelet disorder (QPD) is a unique bleeding disorder that markedly increases urokinase plasminogen activator (uPA) in megakaryocytes and platelets but not in plasma or urine. The cause is tandem duplication of a 78 kb region of chromosome 10 containing PLAU (the uPA gene) and C10orf55, a gene of unknown function. QPD increases uPA in platelets and megakaryocytes >100 fold, far more than expected for a gene duplication. To investigate the tissue-specific effect that PLAU duplication has on gene expression and transcript structure in QPD, we tested if QPD leads to: 1) overexpression of normal or unique PLAU transcripts; 2) increased uPA in leukocytes; 3) altered levels of C10orf55 mRNA and/or protein in megakaryocytes and leukocytes; and 4) global changes in megakaryocyte gene expression. Primary cells and cultured megakaryocytes from donors were prepared for quantitative reverse polymerase chain reaction analyses, RNA-seq and protein expression analyses. Rapidly isolated blood leukocytes from QPD subjects showed only a 3.9 fold increase in PLAU transcript levels, in keeping with the normal to minimally increased uPA in affinity purified, QPD leukocytes. All subjects had more uPA in granulocytes than monocytes and minimal uPA in lymphocytes. QPD leukocytes expressed PLAU alleles in proportions consistent with an extra copy of PLAU on the disease chromosome, unlike QPD megakaryocytes. QPD PLAU transcripts were consistent with reference gene models, with a much higher proportion of reads originating from the disease chromosome in megakaryocytes than granulocytes. QPD and control megakaryocytes contained minimal reads for C10orf55, and C10orf55 protein was not increased in QPD megakaryocytes or platelets. Finally, our QPD megakaryocyte transcriptome analysis revealed a global down regulation of the interferon type 1 pathway. We suggest that the low endogenous levels of uPA in blood are actively regulated, and that the regulatory mechanisms are disrupted in QPD in a megakaryocyte-specific manner. PMID:28301587

Mobilized Peripheral Blood Stem Cells Versus Unstimulated Bone Marrow As a Graft Source for T-Cell-Replete Haploidentical Donor Transplantation Using Post-Transplant Cyclophosphamide.

PubMed

Bashey, Asad; Zhang, Mei-Jie; McCurdy, Shannon R; St Martin, Andrew; Argall, Trevor; Anasetti, Claudio; Ciurea, Stefan O; Fasan, Omotayo; Gaballa, Sameh; Hamadani, Mehdi; Munshi, Pashna; Al Malki, Monzr M; Nakamura, Ryotaro; O'Donnell, Paul V; Perales, Miguel-Angel; Raj, Kavita; Romee, Rizwan; Rowley, Scott; Rocha, Vanderson; Salit, Rachel B; Solh, Melhem; Soiffer, Robert J; Fuchs, Ephraim Joseph; Eapen, Mary

2017-09-10

Purpose T-cell-replete HLA-haploidentical donor hematopoietic transplantation using post-transplant cyclophosphamide was originally described using bone marrow (BM). With increasing use of mobilized peripheral blood (PB), we compared transplant outcomes after PB and BM transplants. Patients and Methods A total of 681 patients with hematologic malignancy who underwent transplantation in the United States between 2009 and 2014 received BM (n = 481) or PB (n = 190) grafts. Cox regression models were built to examine differences in transplant outcomes by graft type, adjusting for patient, disease, and transplant characteristics. Results Hematopoietic recovery was similar after transplantation of BM and PB (28-day neutrophil recovery, 88% v 93%, P = .07; 100-day platelet recovery, 88% v 85%, P = .33). Risks of grade 2 to 4 acute (hazard ratio [HR], 0.45; P < .001) and chronic (HR, 0.35; P < .001) graft-versus-host disease were lower with transplantation of BM compared with PB. There were no significant differences in overall survival by graft type (HR, 0.99; P = .98), with rates of 54% and 57% at 2 years after transplantation of BM and PB, respectively. There were no differences in nonrelapse mortality risks (HR, 0.92; P = .74) but relapse risks were higher after transplantation of BM (HR, 1.49; P = .009). Additional exploration confirmed that the higher relapse risks after transplantation of BM were limited to patients with leukemia (HR, 1.73; P = .002) and not lymphoma (HR, 0.87; P = .64). Conclusion PB and BM grafts are suitable for haploidentical transplantation with the post-transplant cyclophosphamide approach but with differing patterns of treatment failure. Although, to our knowledge, this is the most comprehensive comparison, these findings must be validated in a randomized prospective comparison with adequate follow-up.

Spectra Optia granulocyte apheresis collections result in higher collection efficiency of viable, functional neutrophils in a randomized, crossover, multicenter trial.

PubMed

Cancelas, Jose A; Padmanabhan, Anand; Le, Tuan; Ambruso, Daniel R; Rugg, Neeta; Worsham, D Nicole; Pinkard, Susan L; Graminske, Sharon; Buck, Jennifer; Goldberg, Julie; Bill, Jerry

2015-04-01

Granulocyte transfusion from healthy donors is used in the treatment of patients with granulocyte function defects, or transient neutropenia and severe bacterial or fungal infections resistant to maximal antimicrobial treatment. This study evaluated the performance and safety of the newly developed granulocyte collection protocol of the Spectra Optia in a prospective, multicenter, open-label, randomized, paired crossover trial compared with the COBE Spectra apheresis system in a population of 32 evaluable healthy subjects. All subjects received granulocyte-colony-stimulating factor and dexamethasone before collection. Granulocyte procedures from Spectra Optia apheresis procedures had an approximately 23% higher polymorphonuclear (PMN) collection efficiency (CE) than the COBE Spectra collections (mean, 53.7% vs. 43.2%; p < 0.01), while the platelet CE (10.9% vs. 10.8%, respectively) and hematocrit (7.4% vs. 7.4%) were comparable between collections on both devices. Spectra Optia collections generated a higher total PMN yield per liter of blood processed than those produced by the COBE Spectra (with means of 8.6 × 10(10) vs. 6.8 × 10(10) , respectively). Granulocyte viability was more than 99% with both devices, and chemotaxic and bacterial killing activities of circulating versus collected granulocytes were similarly preserved. Fewer operator adjustments were required with Spectra Optia and there was no significant difference in the number or intensity of adverse events between instruments. CE of the granulocyte collection procedure with the Spectra Optia was approximately 10 percentage points higher than with the COBE Spectra, required less operator involvement, and is safe for clinical implementation. © 2014 AABB.

The Role of Procurement Biopsies in Acceptance Decisions for Kidneys Retrieved for Transplant

PubMed Central

Stewart, Darren E.; Bista, Bipin R.; Salkowski, Nicholas; Snyder, Jon J.; Israni, Ajay K.; Crary, Gretchen S.; Rosendale, John D.; Matas, Arthur J.; Delmonico, Francis L.

2014-01-01

Background and objectives There is a shortage of kidneys for transplant, and many patients on the deceased donor kidney transplant waiting list would likely benefit from kidneys that are currently being discarded. In the United States, the most common reason given for discarding kidneys retrieved for transplant is procurement biopsy results. This study aimed to compare biopsy results from discarded kidneys with discard attributed to biopsy findings, with biopsy results from comparable kidneys that were successfully transplanted. Design, setting, participants, & measurements In this retrospective, observational, case-control study, biopsy reports were examined from 83 kidneys discarded in 2010 due to biopsy findings (cases), 83 contralateral transplanted kidneys from the same donor (contralateral controls), and 83 deceased donors randomly matched to cases by donor risk profile (randomly matched controls). A second procurement biopsy was obtained in 64 of 332 kidneys (19.3%). Results The quality of biopsy reports was low, with amounts of tubular atrophy, interstitial inflammation, arteriolar hyalinosis, and acute tubular necrosis often not indicated; 69% were wedge biopsies and 94% used frozen tissue. The correlation between first and second procurement biopsies was poor; only 25% of the variability (R2) in glomerulosclerosis was explained by biopsies being from the same kidney. The percentages of glomerulosclerosis overlapped substantially between cases, contralateral controls, and randomly matched controls: 17.1%±15.3%, 9.0%±6.6%, and 5.0%±5.9%, respectively. Of all biopsy findings, only glomerulosclerosis>20% was independently correlated with discard (cases versus contralateral controls; odds ratio, 15.09; 95% confidence interval, 2.47 to 92.41; P=0.003), suggesting that only this biopsy result was used in acceptance decisions. One-year graft survival was 79.5% and 90.7% in contralateral and randomly matched controls, respectively, versus 91.6% among all deceased donor transplants in the Scientific Registry of Transplant Recipients. Conclusions Routine use of biopsies could lead to unnecessary kidney discards. PMID:24558053

Platelet activation and function in response to high intensity interval exercise and moderate continuous exercise in CABG and PCI patients.

PubMed

Ahmadizad, Sajad; Nouri-Habashi, Akbar; Rahmani, Hiwa; Maleki, Majid; Naderi, Nasim; Lotfian, Sara; Salimian, Morteza

2016-01-01

The effects of high intensity interval training (HIIT) on inflammatory markers and endothelial function have been extensively shown. However, the acute effect of HIIT on platelet activation and function in patients with recent revascularization is unclear. The purpose of present study was to compare the responses of platelet activation (CD62P) and function (platelet aggregation) to high intensity interval exercise (HIIE) and moderate continuous exercise (MCE) in coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI) patients. Thirty patients who had CABG or PCI were randomly divided into HIIE, MCE and control groups. After determining the VO2peak, subjects in the MCE group carried out 30 min of continuous exercise at 60% of VO2peak, whereas, the subjects in HIIE group performed an interval protocol consisted of 8 repetitions of 2 min activity (running on treadmill) at 90% of VO2peak interspersed by 2 min of active recovery between repetitions at 30% of VO2peak .  Subjects in control group were seated and had no activity for the same period of time. Two blood samples were collected before and immediately after exercise and were analyzed for markers of platelet activation and function. Data analyzes revealed that increases in platelet aggregation induced by ADP and corrected for increases in platelet count in response to MCE trial was significantly lower than HIIE group (P < 0.05). In addition, responses of CD62P to MCE trial was significantly lower compared to HIIE group (P < 0.05). Changes in plateletcrit and platelet distribution width were significantly different among the three trials where the PCT and PDW following the HIIE were higher than MCE. Platelet count increased significantly (P < 0.05) by 13% following HIIE trial. Based on the findings of the present study it could be concluded that the risk of exercise-induced thrombosis is higher during HIIE than MCE in patients with recent revascularization.

Bivalirudin and clopidogrel with and without eptifibatide for elective stenting: effects on platelet function, thrombelastographic indexes, and their relation to periprocedural infarction results of the CLEAR PLATELETS-2 (Clopidogrel with Eptifibatide to Arrest the Reactivity of Platelets) study.

PubMed

Gurbel, Paul A; Bliden, Kevin P; Saucedo, Jorge F; Suarez, Thomas A; DiChiara, Joseph; Antonino, Mark J; Mahla, Elisabeth; Singla, Anand; Herzog, William R; Bassi, Ashwani K; Hennebry, Thomas A; Gesheff, Tania B; Tantry, Udaya S

2009-02-24

The primary objective of this study was to compare the effect of therapy with bivalirudin alone versus bivalirudin plus eptifibatide on platelet reactivity measured by turbidometric aggregometry and thrombin-induced platelet-fibrin clot strength (TIP-FCS) measured by thrombelastography in percutaneous coronary intervention (PCI) patients. The secondary aim was to study the relation of platelet aggregation and TIP-FCS to the occurrence of periprocedural infarction. Bivalirudin is commonly administered alone to clopidogrel naïve (CN) patients and to patients on maintenance clopidogrel therapy (MT) undergoing elective stenting. The effect of adding eptifibatide to bivalirudin on platelet reactivity (PR) and TIP-FCS, and their relation to periprocedural infarction in these patients are unknown. Patients (n = 200) stratified to clopidogrel treatment status were randomly treated with bivalirudin (n = 102) or bivalirudin plus eptifibatide (n = 98). One hundred twenty-eight CN patients were loaded with 600 mg clopidogrel immediately after stenting, and 72 MT patients were not loaded. The PR, TIP-FCS, and myonecrosis markers were serially determined. In CN and MT patients, bivalirudin plus eptifibatide was associated with markedly lower PR at all times (5- and 20-microM adenosine diphosphate-induced, and 15- and 25-microM thrombin receptor activator peptide-induced aggregation; p < 0.001 for all) and reduced mean TIP-FCS (p < 0.05). Patients who had a periprocedural infarction had higher mean 18-h PR (p < 0.0001) and TIP-FCS (p = 0.002). For elective stenting, the addition of eptifibatide to bivalirudin lowered PR to multiple agonists and the tensile strength of the TIP-FCS, 2 measurements strongly associated with periprocedural myonecrosis. Future studies of PR and TIP-FCS for elective stenting may facilitate personalized antiplatelet therapy and enhance the selection of patients for glycoprotein IIb/IIIa blockade. (Peri-Procedural Myocardial Infarction, Platelet Reactivity, Thrombin Generation, and Clot Strength: Differential Effects of Eptifibatide + Bivalirudin Versus Bivalirudin [CLEAR PLATELETS-2]; NCT00370045.

Rationale and design of platelet transfusions in haematopoietic stem cell transplantation: the PATH pilot study.

PubMed

Tay, Jason; Allan, David; Beattie, Sara; Bredeson, Christopher; Fergusson, Dean; Maze, Dawn; Sabloff, Mitchell; Thavorn, Kednapa; Tinmouth, Alan

2016-10-24

In patients with transient thrombocytopenia being treated with high-dose chemotherapy followed by stem cell rescue-haematopoietic stem cell transplantation (HSCT), prophylactic transfusions are standard therapy to prevent bleeding. However, a recent multicentre trial suggests that prophylactic platelet transfusions in HSCT may not be necessary. Additionally, the potential overuse of platelet products places a burden on a scarce healthcare resource. Moreover, the benefit of prophylactic platelet transfusions to prevent clinically relevant haemorrhage is debatable. Current randomised data compare different thresholds for administering prophylactic platelets or prophylactic versus therapeutic platelet transfusions. An alternative strategy involves prescribing prophylactic antifibrinolytic agents such as tranexamic acid to prevent bleeding. This report describes the design of an open-labelled randomised pilot study comparing the prophylactic use of oral tranexamic acid with platelet transfusions in the setting of autologous HSCT. In 3-5 centres, 100 patients undergoing autologous HSCT will be randomly assigned to either a prophylactic tranexamic acid or prophylactic platelets bleeding prevention strategy-based daily platelet values up to 30 days post-transplant. The study will be stratified by centre and type of transplant. The primary goal is to demonstrate study feasibility while collecting clinical outcomes on (1) WHO and Bleeding Severity Measurement Scale (BSMS), (2) transplant-related mortality, (3) quality of life, (4) length of hospital stay, (5) intensive care unit admission rates, (6) Bearman toxicity scores, (7) incidence of infections, (8) transfusion requirements, (9) adverse reactions and (10) economic analyses. This study is funded by a peer-reviewed grant from the Canadian Institutes of Health Research (201 503) and is registered on Clinicaltrials.gov NCT02650791. It has been approved by the Ottawa Health Science Network Research Ethics Board. Study results will presented at national and international conferences. Importantly, the results of this trial will inform the feasibility and conduct of a larger study. NCT02650791; Pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Evaluating the Effect of Intracoronary N-Acetylcysteine on Platelet Activation Markers After Primary Percutaneous Coronary Intervention in Patients With ST-Elevation Myocardial Infarction.

PubMed

Eshraghi, Azadeh; Talasaz, Azita Hajhossein; Salamzadeh, Jamshid; Salarifar, Mojtaba; Pourhosseini, Hamidreza; Nozari, Yones; Bahremand, Mostafa; Jalali, Arash; Boroumand, Mohammad Ali

2016-01-01

During percutaneous coronary intervention (PCI), trauma occurs in the arterial endothelium, resulting in platelet activation and aggregation. As platelet aggregation may lead to coronary thrombosis, antiplatelet agents are essential adjunctive therapies in patients undergoing PCI. The aim of this study was to determine the effect of the intracoronary administration of high-dose N-acetylcysteine (NAC) for the evaluation of its antiplatelet effects in human subjects. In this triple-blind trial, 147 patients undergoing primary PCI were enrolled. Finally, 100 patients were randomized to receive high-dose intracoronary NAC (100 mg/kg bolus, followed by 10 mg·kg⁻¹·h⁻¹ intracoronary continued intravenously for 12 hours) (n = 50) or dextrose solution (n = 50). Platelet activation biomarkers were measured before and 24 hours after the procedure. Secondary end points, comprising all-cause death, reinfarction, and target-vessel revascularization, were assessed at 30 days and 2 years. In comparison with the placebo, NAC could not reduce the level of platelet activation biomarkers within a 24-hour period after its prescription. Major adverse clinical events at 30 days and 2 years were infrequent and not statistically different between the 2 groups. Our results revealed that NAC, compared with the placebo, did not provide an additional clinical benefit as an effective antiplatelet agent after PCI.

Platelet-rich plasma stimulates angiogenesis in mice which may promote hair growth.

PubMed

Cheng, Hanxiao; Zhang, Jufang; Li, Jinsheng; Jia, Ming; Wang, Yuyan; Shen, Haiyan

2017-10-11

Platelet-rich plasma (PRP) is an autologous concentration of human platelets in plasma. In this paper, we aimed to investigate the effect of PRP on hair growth. Platelet-rich plasma and platelet-poor plasma were prepared by sterile centrifugation and injected into shaved dorsal skin of mice (n = 10). Saline injection was used in the control group. The length of randomly plucked hairs was measured at 8, 13, 18 days after PRP injection. Histological examination was preformed to observe the histologic changes of skins. The immunohistochemistry analysis of CD31 was performed to detect the changes of hair length and formation of new vessels. At 13 and 18 days after the last injection, the hair length of mice in PRP group (4.24 ± 0.60 and 8.29 ± 0.48 mm, respectively) was significantly longer compared with the control group (3.70 ± 0.52 and 7.21 ± 0.64 mm, p < 0.05). No significant difference in the hair length was found between the PPP group and the control (p > 0.05). In addition, the number of CD31-positive vessel in the PRP group (9.90 ± 0.60) was more than that in the control group (8.60 ± 2.34, p < 0.05). Platelet-rich plasma might promote hair length growth and increase the number of hair follicles by inducing angiogenesis.

Treatment of normal donors with rhG-CSF 16 micrograms/kg for mobilization of peripheral blood stem cells and their apheretic collection for allogeneic transplantation.

PubMed

Majolino, I; Buscemi, F; Scimé, R; Indovina, A; Santoro, A; Vasta, S; Pampinella, M; Catania, P; Fiandaca, T; Caronia, F

1995-01-01

Utilization of peripheral blood stem cells (PBSC) in allogeneic transplantation requires a method for their mobilization and collection that is not inconvenient for the donor. We administered rhG-CSF (filgrastim) 16 micrograms/kg subcutaneously for 4 days in five normal subjects (age 18-31, M = 3, F = 2), previously selected as HLA-identical donors of siblings with leukemia. All the donors gave written informed consent. On days 4 and 5 (in one donor on day 6 too), 10:l leukapheretic collection was performed with a CS-3000 (Baxter) or an AS-104 (Fresenius) cell separator through the antecubital vein. The WBC count reached a median peak of 57.0 x 10(9)/L on day 5. The peripheral blood CFU-GM peaked to a median level of 8908/mL on day 5 with a median increase over baseline values of 39.1 times. The CD34+ cells peaked to (median) 147.0 x 10(6)/L on day 4 with a median increase of 65.3 times. A lesser enrichment was recorded for BFU-E (median increase 12.7 times) and CFU-GEMM (median increase 15.2 times). Even CD3+ and CD56+CD3- cells increased (median 1.7 and 1.5 times, respectively). A median of 771 x 10(8) MNC (range 672-1378), 116.4 x 10(6) CFU-GM (range 47.7-145.1) and 754 x 10(6) CD34+ cells (range 477-2599) were apheretically collected. Concerning side effects, mild to moderate back pain and general minor discomfort were reported by all donors. The platelet level regularly but transiently decreased after completion of the apheretic procedures with a median nadir of 69 x 10(9)/L (range 43-126) on (median) day 7, but in no case did thrombocytopenia cause bleeding. The thrombocytopenia was more pronounced with the CS-3000 than the AS-104 apparatus. rhG-CSF 16 micrograms/kg x 4 days is an efficient schedule for PBSC mobilization in healthy donors, but lower doses and even a single apheresis procedure might prove similarly adequate.

[A comparative study of unrelated donor and matched-sibling donor allogeneic hematopoietic stem cell transplantation in children and adolescents with acquired severe aplastic anemia].

PubMed

Zhou, J; Fu, Y W; Liang, L J; Wang, Q; Han, L J; Zu, Y L; Zhang, Yanli; Zhu, X H; Yu, F K; Fang, B J; Wei, X D; Song, Y P

2016-12-01

Objective: To evaluate the efficacy of unrelated donor allogeneic hematopoietic stem cell transplantation(URD allo-HSCT) for children and adolescents with severe aplastic anemia (SAA). Methods: Clinical data of 34 SAA children and adolescents undergoing allo-HSCT were retrospectively analyzed from October 2001 to October 2015. According to the source of donor, the patients were divided into matched sibling donor allo-HSCT group (MSD group) and unrelated donor group (URD group). The clinical outcome of SAA children and adolescents receiving URD allo-HSCT was assessed, and patients in MSD allo-HSCT group were enrolled as control at the same period. Results: The rate of hematopoietic reconstitution, the time of neutrophil and platelet engraftment, incidence of chimerism and graft rejection between two groups were not statistically different.The incidence of acute graft-versus-host disease (GVHD) in URD group was significantly higher than that in MSD group [42.9%(6/14) vs 10.5%(2/19), P =0.047]. The incidence of grade Ⅱ-Ⅳ acute GVHD and chronic GVHD in URD were higher than those in MSD group [21.4%(3/14) vs 5.3%(1/19), P =0.288; 35.7%(5/14) vs 5.3%(1/19), P =0.062, respectively], yet without significant difference between two groups. Other transplant-related complications including pulmonary complications, hemorrhagic cystitis, incidence of EBV and CMV reactivation and venous occlusive disease were comparable with two regimens. Estimated 5-years overall survival (OS) rate and disease free survival (DFS) rate were not statistically significant between URD group and MSD group [(84.4±6.6)% vs (89.4±7.1)%, (82.5±5.4)% vs (82.1±4.3)%; P =0.766, P =0.884, respectively]. Conclusions: By multivariate analysis, the outcome of URD allo-HSCT in SAA children and adolescent is similar to MSD allo-HSCT. It could be an alternative option as the first-line treatment for SAA children and adolescents without HLA matched sibling donors.

Ongoing positive effect of platelet-rich plasma versus corticosteroid injection in lateral epicondylitis: a double-blind randomized controlled trial with 2-year follow-up.

PubMed

Gosens, Taco; Peerbooms, Joost C; van Laar, Wilbert; den Oudsten, Brenda L

2011-06-01

Platelet-rich plasma (PRP) has been shown to be a general stimulation for repair and 1-year results showed promising success percentages. This trial was undertaken to determine the effectiveness of PRP compared with corticosteroid injections in patients with chronic lateral epicondylitis with a 2-year follow-up. Randomized controlled trial; Level of evidence, 1. The trial was conducted in 2 Dutch teaching hospitals. One hundred patients with chronic lateral epicondylitis were randomly assigned to a leukocyte-enriched PRP group (n = 51) or the corticosteroid group (n = 49). Randomization and allocation to the trial group were carried out by a central computer system. Patients received either a corticosteroid injection or an autologous platelet concentrate injection through a peppering needling technique. The primary analysis included visual analog scale (VAS) pain scores and Disabilities of the Arm, Shoulder and Hand (DASH) outcome scores. The PRP group was more often successfully treated than the corticosteroid group (P < .0001). Success was defined as a reduction of 25% on VAS or DASH scores without a reintervention after 2 years. When baseline VAS and DASH scores were compared with the scores at 2-year follow-up, both groups significantly improved across time (intention-to-treat principle). However, the DASH scores of the corticosteroid group returned to baseline levels, while those of the PRP group significantly improved (as-treated principle). There were no complications related to the use of PRP. Treatment of patients with chronic lateral epicondylitis with PRP reduces pain and increases function significantly, exceeding the effect of corticosteroid injection even after a follow-up of 2 years. Future decisions for application of PRP for lateral epicondylitis should be confirmed by further follow-up from this trial and should take into account possible costs and harms as well as benefits.

Platelet-rich-plasmapheresis for minimising peri-operative allogeneic blood transfusion.

PubMed

Carless, Paul A; Rubens, Fraser D; Anthony, Danielle M; O'Connell, Dianne; Henry, David A

2011-03-16

Concerns regarding the safety of transfused blood have generated considerable enthusiasm for the use of technologies intended to reduce the use of allogeneic blood (blood from an unrelated donor). Platelet-rich plasmapheresis (PRP) offers an alternative approach to blood conservation. To examine the evidence for the efficacy of PRP in reducing peri-operative allogeneic red blood cell (RBC) transfusion, and the evidence for any effect on clinical outcomes such as mortality and re-operation rates. We identified studies by searching MEDLINE (1950 to 2009), EMBASE (1980 to 2009), The Cochrane Library (Issue 1, 2009), the Internet (to March 2009) and the reference lists of published articles, reports, and reviews. Controlled parallel group trials in which adult patients, scheduled for non-urgent surgery, were randomised to PRP, or to a control group which did not receive the intervention. Primary outcomes measured were: the number of patients exposed to allogeneic RBC transfusion, and the amount of RBC transfused. Other outcomes measured were: the number of patients exposed to allogeneic platelet transfusions, fresh frozen plasma, and cryoprecipitate, blood loss, re-operation for bleeding, post-operative complications (thrombosis), mortality, and length of hospital stay. Treatment effects were pooled using a random-effects model. Trial quality was assessed using criteria proposed by Schulz et al (Schulz 1995). Twenty-two trials of PRP were identified that reported data for the number of patients exposed to allogeneic RBC transfusion. These trials evaluated a total of 1589 patients. The relative risk (RR) of exposure to allogeneic blood transfusion in those patients randomised to PRP was 0.73 (95%CI 0.59 to 0.90), equating to a relative risk reduction (RRR) of 27% and a risk difference (RD) of 19% (95%CI 10% to 29%). However, significant heterogeneity of treatment effect was observed (p < 0.00001; I² = 79%). When the four trials by Boldt are excluded, the RR is 0.76 (95% CI 0.62 to 0.93). On average, PRP did not significantly reduce the total volume of RBC transfused (weighted mean difference [WMD] -0.69, 95%CI -1.93 to 0.56 units). Trials provided inadequate data regarding the impact of PRP on morbidity, mortality, and hospital length of stay. Trials were generally small and of poor methodological quality. Although the results suggest that PRP is effective in reducing allogeneic RBC transfusion in adult patients undergoing elective surgery, there was considerable heterogeneity of treatment effects and the trials were of poor methodological quality. The available studies provided inadequate data for firm conclusions to be drawn regarding the impact of PRP on clinically important endpoints.

Quantum confinement of a hydrogenic donor in a double quantum well: Through diamagnetic susceptibility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vignesh, G.; Nithiananthi, P., E-mail: nithyauniq@gmail.com

2015-06-24

Diamagnetic susceptibility of a randomly distributed donor in a GaAs/Al{sub 0.3}Ga{sub 0.7}As Double Quantum Well has been calculated in its ground state as a function of barrier and well width. It is shown that the modification in the barrier and well dimension significantly influences the dimensional character of the donor through modulating the subband distribution and in turn the localization of the donor. The effect of barrier and well thickness on the interparticle distance has also been observed. Interestingly it opens up the possibility of tuning the susceptibility and monitoring the tunnel coupling among the wells.

Quantum confinement of a hydrogenic donor in a double quantum well: Through diamagnetic susceptibility

NASA Astrophysics Data System (ADS)

Vignesh, G.; Nithiananthi, P.

2015-06-01

Diamagnetic susceptibility of a randomly distributed donor in a GaAs/Al0.3Ga0.7As Double Quantum Well has been calculated in its ground state as a function of barrier and well width. It is shown that the modification in the barrier and well dimension significantly influences the dimensional character of the donor through modulating the subband distribution and in turn the localization of the donor. The effect of barrier and well thickness on the interparticle distance has also been observed. Interestingly it opens up the possibility of tuning the susceptibility and monitoring the tunnel coupling among the wells.

Normalized levels of red blood cells expressing phosphatidylserine, their microparticles, and activated platelets in young patients with β-thalassemia following bone marrow transplantation.

PubMed

Klaihmon, Phatchanat; Vimonpatranon, Sinmanus; Noulsri, Egarit; Lertthammakiat, Surapong; Anurathapan, Usanarat; Sirachainan, Nongnuch; Hongeng, Suradej; Pattanapanyasat, Kovit

2017-10-01

Bone marrow transplantation (BMT) serves as the only curative treatment for patients with β-thalassemia major; however, hemostatic changes have been observed in these BMT patients. Aggregability of thalassemic red blood cells (RBCs) and increased red blood cell-derived microparticles (RMPs) expressing phosphatidylserine (PS) are thought to participate in thromboembolic events by initially triggering platelet activation. To our knowledge, there has been no report providing quantitation of these circulating PS-expressing RBCs and RMPs in young β-thalassemia patients after BMT. Whole blood from each subject was fluorescently labeled to detect RBC markers (CD235a) and annexin-V together with the known number TruCount™ beads. PS-expressing RBCs, RMPs, and activated platelets were identified by flow cytometry. In our randomized study, we found the decreased levels of three aforementioned factors compared to levels in patients receiving regular blood transfusion (RT). This study showed that BMT in β-thalassemia patients decreases the levels of circulating PS-expressing RBCs, their MPs, and procoagulant platelets when compared to patients who received RT. Normalized levels of these coagulation markers may provide the supportive evidence of the effectiveness of BMT for curing thalassemia.

Evaluation of platelet adhesion and activation on polymers: Round-robin study to assess inter-center variability.

PubMed

Braune, S; Sperling, C; Maitz, M F; Steinseifer, U; Clauser, J; Hiebl, B; Krajewski, S; Wendel, H P; Jung, F

2017-10-01

The regulatory agencies provide recommendations rather than protocols or standard operation procedures for the hemocompatibility evaluation of novel materials e.g. for cardiovascular applications. Thus, there is a lack of specifications with regard to test setups and procedures. As a consequence, laboratories worldwide perform in vitro assays under substantially different test conditions, so that inter-laboratory and inter-study comparisons are impossible. Here, we report about a prospective, randomized and double-blind multicenter trial which demonstrates that standardization of in vitro test protocols allows a reproducible assessment of platelet adhesion and activation from fresh human platelet rich plasma as possible indicators of the thrombogenicity of cardiovascular implants. Standardization of the reported static in vitro setup resulted in a laboratory independent scoring of the following materials: poly(dimethyl siloxane) (PDMS), poly(ethylene terephthalate) (PET) and poly(tetrafluoro ethylene) (PTFE). The results of this in vitro study provide evidence that inter-laboratory and inter-study comparisons can be achieved for the evaluation of the adhesion and activation of platelets on blood-contacting biomaterials by stringent standardization of test protocols. Copyright © 2017 Elsevier B.V. All rights reserved.

Does microbial contamination influence the success of the hematopoietic cell transplantation outcomes?

PubMed

Dal, Mehmet Sinan; Tekgündüz, Emre; Çakar, Merih Kızıl; Kaya, Ali Hakan; Namdaroğu, Sinem; Batgi, Hikmetullah; Bekdemir, Filiz; Uncu Ulu, Bahar; Yiğenoğlu, Tuğçe Nur; Kılınç, Ali; İskender, Dicle; Uğur, Bilge; Koçubaba, Şerife; İskender, Gülşen; Altuntaş, Fevzi

2016-08-01

Microbial contamination can be a marker for faulty process and is assumed to play an important role in the collection of hematopoietic progenitor cell (HPC) and infusion procedure. We aimed to determine the microbial contamination rates and evaluate the success of hematopoietic cell transplantation (HCT) in patients who received contaminated products. We analyzed microbial contamination records of HPC grafts between 2012 and 2015, retrospectively. Contamination rates of autologous donors were evaluated for at three steps: at the end of mobilization, following processing with dimethyl sulfoxide, and just before stem cell infusion. Grafts of allogeneic donors were assessed only before HCT. A total of 445 mobilization procedures were carried out on 333 (167 autologous and 166 allogeneic) donors. The microbiological contamination of peripheral blood (323/333 donations) and bone marrow (10/333 donations) products were analyzed. Bacterial contamination was detected in 18 of 1552 (1.15 %) culture bottles of 333 donors. During the study period 248 patients underwent HCT and among these patients microbial contamination rate on sample basis was 1.3 % (16/1212). Microbial contamination detected in nine patients (7 autologous; 2 allogeneic). In 8 of 9 patients, a febrile neutropenic attack was observed. The median day for the neutropenic fever was 4 days (0-9). None of the patients died within the post-transplant 30 days who received contaminated products. The use of contaminated products with antibiotic prophylaxis may be safe in terms of the first day of fever, duration of fever, neutrophil, platelet engraftment and duration of hospitalization. Copyright © 2016 Elsevier Ltd. All rights reserved.

Establishing criteria for human mesenchymal stem cell potency.

PubMed

Samsonraj, Rebekah M; Rai, Bina; Sathiyanathan, Padmapriya; Puan, Kia Joo; Rötzschke, Olaf; Hui, James H; Raghunath, Michael; Stanton, Lawrence W; Nurcombe, Victor; Cool, Simon M

2015-06-01

This study sought to identify critical determinants of mesenchymal stem cell (MSC) potency using in vitro and in vivo attributes of cells isolated from the bone marrow of age- and sex-matched donors. Adherence to plastic was not indicative of potency, yet capacity for long-term expansion in vitro varied considerably between donors, allowing the grouping of MSCs from the donors into either those with high-growth capacity or low-growth capacity. Using this grouping strategy, high-growth capacity MSCs were smaller in size, had greater colony-forming efficiency, and had longer telomeres. Cell-surface biomarker analysis revealed that the International Society for Cellular Therapy (ISCT) criteria did not distinguish between high-growth capacity and low-growth capacity MSCs, whereas STRO-1 and platelet-derived growth factor receptor alpha were preferentially expressed on high-growth capacity MSCs. These cells also had the highest mean expression of the mRNA transcripts TWIST-1 and DERMO-1. Irrespective of these differences, both groups of donor MSCs produced similar levels of key growth factors and cytokines involved in tissue regeneration and were capable of multilineage differentiation. However, high-growth capacity MSCs produced approximately double the volume of mineralized tissue compared to low-growth capacity MSCs when assessed for ectopic bone-forming ability. The additional phenotypic criteria presented in this study when combined with the existing ISCT minimum criteria and working proposal will permit an improved assessment of MSC potency and provide a basis for establishing the quality of MSCs prior to their therapeutic application. © 2015 AlphaMed Press.

Hematopoietic Cell Transplantation Using Reduced-Intensity Conditioning Is Successful in Children with Hematologic Cytopenias of Genetic Origin.

PubMed

Kothari, Alok; Ngwube, Alexander; Hayashi, Robert; Murray, Lisa; Davis, Jeffrey; Haut, Paul; Loechelt, Brett J; Shenoy, Shalini

2015-07-01

Genetically derived hematologic cytopenias are a rare heterogeneous group of disorders. Allogeneic hematopoietic cell transplantation (HCT) is curative but offset by organ toxicities from the preparative regimen, graft rejection, graft-versus-host disease (GVHD), or mortality. Because of these possibilities, consideration of HCT can be delayed, especially in the unrelated donor setting. We report a prospective multicenter trial of reduced-intensity conditioning (RIC) with alemtuzumab, fludarabine, and melphalan and HCT in 11 children with marrow failure of genetic origin (excluding Fanconi anemia) using the best available donor source (82% from unrelated donors). The median age at transplantation was 23 months (range, 2 months to 14 years). The median times to neutrophil (>500 × 10(6)/L) and platelet (>50 × 10(9)/L) engraftment were 13 (range, 12 to 24) and 30 (range, 7 to 55) days, respectively. The day +100 probability of grade II to IV acute GVHD and the 1-year probability of limited and extensive GVHD were 9% and 27%, respectively. The probability of 5-year overall and event-free survival was 82%; 9 patients were alive with normal blood counts at last follow-up and all were successfully off systemic immunosuppression. In patients with genetically derived severe hematologic cytopenias, allogeneic HCT with this RIC regimen was successful in achieving a cure. This experience supports consideration of HCT early in such patients even in the absence of suitable related donors. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

What motivates men to donate blood? A systematic review of the evidence.

PubMed

Carver, A; Chell, K; Davison, T E; Masser, B M

2018-04-01

Effective recruitment and retention of male donors are vital for the ongoing provision of blood products. Compared with females, male donors are less likely to be medically deferred or experience vasovagal reactions and are typically preferred for plasmapheresis donation in voluntary non-remunerated settings. However, females outnumber males among donors aged under 40 years. This systematic review aimed to synthesize evidence and identify key motivators for blood donation among males to inform targeted recruitment/retention campaigns. Databases (e.g. EBSCOhost, Web of Science) were searched using terms (dona* OR dono*) AND (blood OR aphaeresis OR apheresis OR plasma* OR platelet* OR platlet*) in title AND (male OR gender OR sex OR female) AND (motivat* OR intention OR attitude OR behavi* OR predictor OR barrier OR deter*) NOT (organ OR sperm OR tissue OR autologous OR oocyte) in text. Two researchers independently systematically scanned quantitative, full-text, English language, peer-reviewed publications from 1990 to 2015 that examined males/females separately with outcomes of blood donation or self-reported intention. Two additional researchers resolved discrepancies. Among 28 identified articles, the most frequently cited motivators for male blood product donation were as follows: altruism; positive attitude towards incentives; health check(s); subjective norms. Altruism was less pronounced among males compared with females and was combined with 'warm glow' in novice males (impure altruism). Perceived health benefits and incentives (e.g. coffee mugs) were stronger motivators of males than females. Marketing campaigns for recruitment/retention of male donors should focus on identified motivators rather than take a 'one-size-fits-all' approach. © 2017 International Society of Blood Transfusion.

Methotrexate as a preferential cyclooxygenase 2 inhibitor in whole blood of patients with rheumatoid arthritis.

PubMed

Mello, S B; Barros, D M; Silva, A S; Laurindo, I M; Novaes, G S

2000-05-01

To investigate the regulation of whole-blood cyclooxygenase-1 and -2 (COX-2 and COX-1) activities by methotrexate (MTX) in rheumatoid arthritis (RA) patients. Whole blood was withdrawn from nine healthy volunteers, 12 RA patients treated with MTX (RA/MTX) and six RA patients treated with chloroquine (RA/CQ). COX-1 activity was quantified as platelet thromboxane B(2) production in unstimulated blood and COX-2 activity was measured as prostaglandin E(2) (PGE(2)) production in whole blood stimulated with LPS. Thromboxane B(2) and PGE(2) were measured by radioimmunoassay. We studied the drug effect in vitro by direct incubation of MTX with blood obtained from normal donors. Ex vivo assays were performed with blood collected from RA/MTX and RA/CQ patients. The influence of serum factors on enzyme activities was analysed in blood collected from normal donors and incubated with RA/MTX, autologous or heterologous serum. In vitro assays showed no direct action of MTX on the activity of either enzyme. Assays performed with blood from RA/MTX patients showed preferential inhibition of COX-2 activity (PGE(2) = 10.11 +/- 2.42 ng/ml) when compared with blood of normal donors (PGE(2) = 37.7 +/- 4.36 ng/ml; P = 0.001). Inhibition of COX-2 activity was also observed when blood of normal donors was co-incubated with RA/MTX serum. Our results clearly show that the anti-inflammatory action of low-dose MTX is partly mediated by a serum factor induced by MTX or a MTX metabolite that preferentially inhibits the activity of COX-2.

Treating pain on skin graft donor sites: Review and clinical recommendations.

PubMed

Sinha, Sarthak; Schreiner, Amanda J; Biernaskie, Jeff; Nickerson, Duncan; Gabriel, Vincent A

2017-11-01

Split-thickness skin grafting is the most common reconstructive procedure in managing burn injuries. Harvesting split-thickness skin creates a new partial thickness wound referred to as the donor site. Pain at the donor site is reported to be one of the most distressing symptoms during the early postoperative period. Here, we (a) identify strategies for managing donor site pain, (b) assess the quality of individual studies, and (c) formulate evidence-based recommendations based on the amount and consistency of evidence. Our analysis revealed five distinct approaches to minimize donor site pain. These include: continuous subcutaneous local anesthetic infusion (three studies), subcutaneous anesthetic injection (five studies), topical agents (six studies), nonpharmacological interventions (three studies), and wound dressings (18 studies). Available randomized control trials typically evaluated pain on standardized scales (i.e. Visual Analog Scale, Numerical Rating Scale), and compared the experimental group with standard care. Recommended treatments include: (a) subcutaneous anesthetic injection of adrenaline-lidocaine; (b) ice application; (c) topical agents, such as lidocaine and bupivacaine; and (d) hydrocolloid- and polyurethane-based wound dressings accompanied with fibrin sealant. Methodologically sound randomized control trials examining the efficacy of modified tumescent solution, ropivacaine, plasma therapy, noncontact ultrasound, and morphine gels are lacking and should be a priority for future research.

A Postmortem Study of Frontal and Temporal Gyri Thickness and Cell Number in Human Obesity.

PubMed

Gómez-Apo, Erick; García-Sierra, Adrián; Silva-Pereyra, Juan; Soto-Abraham, Virgilia; Mondragón-Maya, Alejandra; Velasco-Vales, Verónica; Pescatello, Linda S

2018-01-01

This study aimed to compare cortex thickness and neuronal cell density in postmortem brain tissue from people with overweight or obesity and normal weight. The cortex thickness and neuron density of eight donors with overweight or obesity (mean = 31.6 kg/m 2 ; SD = 4.35; n = 8; 6 male) and eight donors with normal weight (mean = 21.8 kg/m 2 ; SD = 1.5; n = 8; 5 male) were compared. All participants were Mexican and lived in Mexico City. Randomly selected thickness measures of different cortex areas from the frontal and temporal lobes were analyzed based on high-resolution real-size photographs. A histological analysis of systematic-random fields was used to quantify the number of neurons in postmortem left and right of the first, second, and third gyri of frontal and temporal lobe brain samples. No statistical difference was found in cortical thickness between donors with overweight or obesity and individuals with normal weight. A smaller number of neurons was found among the donors with overweight or obesity than the donors with normal weight at different frontal and temporal areas. A lower density of neurons is associated with overweight or obesity. The morphological basis for structural brain changes in obesity requires further investigation. © 2017 The Obesity Society.

Does platelet-rich plasma have a role in the treatment of osteoarthritis?

PubMed

Ornetti, Paul; Nourissat, Geoffroy; Berenbaum, Francis; Sellam, Jérémie; Richette, Pascal; Chevalier, Xavier

2016-01-01

Platelet-rich plasma (PRP) has been generating considerable attention as an intra-articular treatment to alleviate the symptoms of osteoarthritis. Activated platelets release a host of soluble mediators such as growth factors and cytokines, thereby inducing complex interactions that vary across tissues within the joint. In vivo, PRP may promote chondrocyte proliferation and differentiation. The available data are somewhat conflicting regarding potential effects on synovial cells and angiogenesis modulation. PRP probably exerts an early anti-inflammatory effect, which may be chiefly mediated by inhibition of the NF-κB pathway, a hypothesis that requires confirmation by proof-of-concept studies. It is far too early to draw conclusions about the efficacy of PRP as a treatment for hip osteoarthritis. The only randomized trial versus hyaluronic acid showed no significant difference in effects, and no placebo-controlled trials are available. Most of the randomized trials in knee osteoarthritis support a slightly greater effect in alleviating the symptoms compared to visco-supplementation, most notably at the early stages of the disease, although only medium-term data are available. Many uncertainties remain, however, regarding the best administration regimen. Serious adverse effects, including infections and allergies, seem rare, although post-injection pain is more common than with other intra-articular treatments for osteoarthritis. Copyright © 2015 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

Comparison between the effect of omeprazole and rabeprazole on the antiplatelet action of clopidogrel.

PubMed

Siriswangvat, Suksiri; Sansanayudh, Nakarin; Nathisuwan, Surakit; Panomvana, Duangchit

2010-10-01

Emerging data suggests that several proton pump inhibitors (PPIs), including omeprazole, might interfere with the antiplatelet action of clopidogrel. However, there is a lack of data for rabeprazole. This study aimed to investigate and compare the impact of omeprazole and rabeprazole on the antiplatelet action of clopidogrel among patients with coronary artery disease (CAD). A prospective, randomized, open-labeled study was conducted among 87 CAD patients receiving clopidogrel and aspirin. Forty three and 44 patients were randomized to receive omeprazole 20 mg and rabeprazole 20 mg once daily, respectively, for at least 2 weeks. Adenosine 5-diphosphate 20 µmol/L-induced platelet aggregation was performed before and after PPIs treatment. Mean maximal platelet aggregation (MPA) before and after PPIs treatment of both groups were compared. At baseline, there were no significant differences in the mean MPA between the omeprazole and rabeprazole groups (40.68 ± 18.82% vs 36.42 ± 21.39%; P=0.326). After a 2-week treatment with PPIs, the mean MPA in both groups significantly increased from baseline and there were no differences between the omeprazole and rabeprazole groups (55.73 ± 19.66% vs 48.46 ± 18.80%; P=0.141). Both omeprazole and rabeprazole decreased the antiplatelet effect of clopidogrel. Use of these agents resulted in a similar degree of interference on clopidogrel's action, as measured by ADP-induced platelet aggregation. 

Quantitative analysis of random migration of cells using time-lapse video microscopy.

PubMed

Jain, Prachi; Worthylake, Rebecca A; Alahari, Suresh K

2012-05-13

Cell migration is a dynamic process, which is important for embryonic development, tissue repair, immune system function, and tumor invasion (1, 2). During directional migration, cells move rapidly in response to an extracellular chemotactic signal, or in response to intrinsic cues (3) provided by the basic motility machinery. Random migration occurs when a cell possesses low intrinsic directionality, allowing the cells to explore their local environment. Cell migration is a complex process, in the initial response cell undergoes polarization and extends protrusions in the direction of migration (2). Traditional methods to measure migration such as the Boyden chamber migration assay is an easy method to measure chemotaxis in vitro, which allows measuring migration as an end point result. However, this approach neither allows measurement of individual migration parameters, nor does it allow to visualization of morphological changes that cell undergoes during migration. Here, we present a method that allows us to monitor migrating cells in real time using video - time lapse microscopy. Since cell migration and invasion are hallmarks of cancer, this method will be applicable in studying cancer cell migration and invasion in vitro. Random migration of platelets has been considered as one of the parameters of platelet function (4), hence this method could also be helpful in studying platelet functions. This assay has the advantage of being rapid, reliable, reproducible, and does not require optimization of cell numbers. In order to maintain physiologically suitable conditions for cells, the microscope is equipped with CO(2) supply and temperature thermostat. Cell movement is monitored by taking pictures using a camera fitted to the microscope at regular intervals. Cell migration can be calculated by measuring average speed and average displacement, which is calculated by Slidebook software.

Silver-coated nylon dressing plus active DC microcurrent for healing of autogenous skin donor sites.

PubMed

Malin, Edward W; Galin, Chaya M; Lairet, Kimberley F; Huzar, Todd F; Williams, James F; Renz, Evan M; Wolf, Steven E; Cancio, Leopoldo C

2013-11-01

Burn wounds are a significant cause of morbidity and mortality, and improved outcomes are demonstrated with early closure of both primary burn wounds and skin donor sites. Thus, technology that decreases the healing time of burns and donor sites would be potentially lifesaving. We present the results of a single-center, prospective, double-blinded, randomized controlled trial to evaluate the efficacy of silver-coated dressing with active microcurrent in comparison to silver-coated dressing with sham microcurrent on wound-closure time for autogenous skin donor sites. Four hundred five patients were screened for treatment of their donor sites using a silver-coated nylon dressing with either sham or active microcurrent stimulation. Thirty patients were enrolled in the study and then randomized. Of these, 5 patients were removed from analysis due to protocol deviations. Differences in time-to-closure were analyzed using Kaplan-Meier analysis and the proportional hazard regression model. Subjective verbal pain rating scores (0-10; 0, no pain; 10, worst pain) were also recorded. All devices were blinded and programmed at an outside facility, so that every patient had either an active or sham device. The study was unblinded only after the final patient's donor site had healed. All patients achieved donor-site healing before postoperative day 20. The 14 patients in the active microcurrent group [mean, 10.8 (2.9) days; range, 7-15 days] experienced no difference in time to wound healing as compared to the remaining patients in the sham microcurrent group [mean, 11.1 (2.0) days; range, 8-14 days; P = 0.75]. There were no differences in pain from one group compared to the other. None of the donor sites exhibited clinical signs of infection. In a sample size of 25 burn patients, the addition of direct microcurrent to silver-nylon dressings did not decrease time to wound closure of skin donor sites, and it did not show a difference in reported pain levels.

Dabigatran reversal with idarucizumab in a patient undergoing heart transplantation: first European report.

PubMed

Tralhão, António; Aguiar, Carlos; Ferreira, Jorge; Rebocho, Maria José; Santos, Emília; Martins, Dinis; Neves, José Pedro

2017-01-01

Dabigatran is a direct thrombin inhibitor with a favorable effectiveness and safety profile when compared to vitamin K antagonists, both in randomized trials and real world registries of atrial fibrillation patients. Yet, physicians' fear of high bleeding risk scenarios in daily clinical practice still precludes a more widespread use of oral anticoagulation. We hereby report a successful case of dabigatran reversal with the novel monoclonal antibody fragment idarucizumab in a patient undergoing heart transplantation. A 45-year old male patient on dabigatran for atrial fibrillation thromboprophylaxis was enlisted for heart transplantation due to end-stage ischemic heart failure. Upon donor availability and suitability and following the last intake of the drug 12 h previously, activated partial thromboplastin time was measured and found to be elevated. After general anesthesia and before extracorporeal circulation, idarucizumab was administered as two boluses of 2.5 g. Orthotopic heart transplantation ensued under full heparinization and cardiopulmonary bypass. Total chest tube output was 1125 mL after 3 days and 4 units of fresh frozen plasma and one platelet pool were administered in the operating room without further need for blood products. The post-operative period was uneventful. Idarucizumab was associated with an effective hemostasis in the setting of heart transplantation. Dabigatran may be considered as an alternative to vitamin K antagonists in heart transplant candidates with an indication for oral anticoagulation.

Prophylactic platelet transfusion plus supportive care versus supportive care alone in adults with dengue and thrombocytopenia: a multicentre, open-label, randomised, superiority trial.

PubMed

Lye, David C; Archuleta, Sophia; Syed-Omar, Sharifah F; Low, Jenny G; Oh, Helen M; Wei, Yuan; Fisher, Dale; Ponnampalavanar, Sasheela S L; Wijaya, Limin; Lee, Linda K; Ooi, Eng-Eong; Kamarulzaman, Adeeba; Lum, Lucy C; Tambyah, Paul A; Leo, Yee-Sin

2017-04-22

Dengue is the commonest vector-borne infection worldwide. It is often associated with thrombocytopenia, and prophylactic platelet transfusion is widely used despite the dearth of robust evidence. We aimed to assess the efficacy and safety of prophylactic platelet transfusion in the prevention of bleeding in adults with dengue and thrombocytopenia. We did an open-label, randomised, superiority trial in five hospitals in Singapore and Malaysia. We recruited patients aged at least 21 years who had laboratory-confirmed dengue (confirmed or probable) and thrombocytopenia (≤20 000 platelets per μL), without persistent mild bleeding or any severe bleeding. Patients were assigned (1:1), with randomly permuted block sizes of four or six and stratified by centre, to receive prophylactic platelet transfusion in addition to supportive care (transfusion group) or supportive care alone (control group). In the transfusion group, 4 units of pooled platelets were given each day when platelet count was 20 000 per μL or lower; supportive care consisted of bed rest, fluid therapy, and fever and pain medications. The primary endpoint was clinical bleeding (excluding petechiae) by study day 7 or hospital discharge (whichever was earlier), analysed by intention to treat. Safety outcomes were analysed according to the actual treatment received. This study was registered with ClinicalTrials.gov, number NCT01030211, and is completed. Between April 29, 2010, and Dec 9, 2014, we randomly assigned 372 patients to the transfusion group (n=188) or the control group (n=184). The intention-to-treat analysis included 187 patients in the transfusion group (one patient was withdrawn immediately) and 182 in the control group (one was withdrawn immediately and one did not have confirmed or probable dengue). Clinical bleeding by day 7 or hospital discharge occurred in 40 (21%) patients in the transfusion group and 48 (26%) patients in the control group (risk difference -4·98% [95% CI -15·08 to 5·34]; relative risk 0·81 [95% CI 0·56 to 1·17]; p=0·16). 13 adverse events occurred in the transfusion group and two occurred in the control group (5·81% [-4·42 to 16·01]; 6·26 [1·43 to 27·34]; p=0·0064). Adverse events that were possibly, probably, or definitely related to transfusion included three cases of urticaria, one maculopapular rash, one pruritus, and one chest pain, as well as one case each of anaphylaxis, transfusion-related acute lung injury, and fluid overload that resulted in serious adverse events. No death was reported. In adult patients with dengue and thrombocytopenia, prophylactic platelet transfusion was not superior to supportive care in preventing bleeding, and might be associated with adverse events. National Medical Research Council, Singapore. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of platelet-rich plasma on osseous healing in dogs undergoing high tibial osteotomy.

PubMed

Franklin, Samuel P; Burke, Emily E; Holmes, Shannon P

2017-01-01

The purpose of this study was to investigate whether platelet-rich plasma (PRP) enhances osseous healing in conjunction with a high tibial osteotomy in dogs. Randomized controlled trial. Sixty-four client-owned pet dogs with naturally occurring rupture of the anterior cruciate ligament and that were to be treated with a high tibial osteotomy (tibial plateau leveling osteotomy) were randomized into the treatment or control group. Dogs in the treatment group received autologous platelet-rich plasma activated with calcium chloride and bovine thrombin to produce a well-formed PRP gel that was placed into the osteotomy at the time of surgery. Dogs in the control group received saline lavage of the osteotomy. All dogs had the osteotomy stabilized with identical titanium alloy implants and all aspects of the surgical procedure and post-operative care were identical among dogs of the two groups. Bone healing was assessed at exactly 28, 49, and 70 days after surgery with radiography and ultrasonography and with MRI at day 28. The effect of PRP on bone healing was assessed using a repeated measures analysis of covariance with radiographic and ultrasonographic data and using a t-test with the MRI data. Sixty dogs completed the study. There were no significant differences in age, weight, or gender distribution between the treatment and control groups. Twenty-seven dogs were treated with PRP and 33 were in the control group. The average platelet concentration of the PRP was 1.37x106 platelets/μL (±489x103) with a leukocyte concentration of 5.45x103/μL (±3.5x103). All dogs demonstrated progressive healing over time and achieved clinically successful outcomes. Time since surgery and patient age were significant predictors of radiographic healing and time since surgery was a significant predictor of ultrasonographic assessment of healing. There was no significant effect of PRP treatment as assessed radiographically, ultrasonographically, or with MRI. The PRP used in this study did not hasten osseous union in dogs treated with a high tibial osteotomy.

The effect of platelet-rich plasma on osseous healing in dogs undergoing high tibial osteotomy

PubMed Central

Burke, Emily E.; Holmes, Shannon P.

2017-01-01

Objectives The purpose of this study was to investigate whether platelet-rich plasma (PRP) enhances osseous healing in conjunction with a high tibial osteotomy in dogs. Study design Randomized controlled trial. Methods Sixty-four client-owned pet dogs with naturally occurring rupture of the anterior cruciate ligament and that were to be treated with a high tibial osteotomy (tibial plateau leveling osteotomy) were randomized into the treatment or control group. Dogs in the treatment group received autologous platelet-rich plasma activated with calcium chloride and bovine thrombin to produce a well-formed PRP gel that was placed into the osteotomy at the time of surgery. Dogs in the control group received saline lavage of the osteotomy. All dogs had the osteotomy stabilized with identical titanium alloy implants and all aspects of the surgical procedure and post-operative care were identical among dogs of the two groups. Bone healing was assessed at exactly 28, 49, and 70 days after surgery with radiography and ultrasonography and with MRI at day 28. The effect of PRP on bone healing was assessed using a repeated measures analysis of covariance with radiographic and ultrasonographic data and using a t-test with the MRI data. Results Sixty dogs completed the study. There were no significant differences in age, weight, or gender distribution between the treatment and control groups. Twenty-seven dogs were treated with PRP and 33 were in the control group. The average platelet concentration of the PRP was 1.37x106 platelets/μL (±489x103) with a leukocyte concentration of 5.45x103/μL (±3.5x103). All dogs demonstrated progressive healing over time and achieved clinically successful outcomes. Time since surgery and patient age were significant predictors of radiographic healing and time since surgery was a significant predictor of ultrasonographic assessment of healing. There was no significant effect of PRP treatment as assessed radiographically, ultrasonographically, or with MRI. Conclusion The PRP used in this study did not hasten osseous union in dogs treated with a high tibial osteotomy. PMID:28520812

Differences between blood donors and a population sample: implications for case-control studies.

PubMed

Golding, Jean; Northstone, Kate; Miller, Laura L; Davey Smith, George; Pembrey, Marcus

2013-08-01

Selecting appropriate controls for studies of genetic variation in case series is important. The two major candidates involve the use of blood donors or a random sample of the population. We compare and contrast the two different populations of controls for studies of genetic variation using data from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). In addition we compute different biases using a series of hypothetical assumptions. The study subjects who had been blood donors differed markedly from the general population in social, health-related, anthropometric, and personality-related variables. Using theoretical examples, we show that blood donors are a poor control group for non-genetic studies of diseases related to environmentally, behaviourally, or socially patterned exposures. However, we show that if blood donors are used as controls in genetic studies, these factors are unlikely to make a major difference in detecting true associations with relatively rare disorders (cumulative incidence through life of <10%). Nevertheless, for more common disorders, the reduction in accuracy resulting from the inclusion in any control population of individuals who have or will develop the disease in question can create a greater bias than can socially patterned factors. Information about the medical history of a control and the parents of the control (as a proxy for whether the control will develop the disease) is more important with regard to the choice of controls than whether the controls are a random population sample or blood donors.

A prospective comparison of a new, synthetic donor site dressing versus an impregnated gauze dressing.

PubMed

Hickerson, W L; Kealey, G P; Smith, D J; Thomson, P D

1994-01-01

Three institutions enrolled 38 patients who required bilateral skin graft donor sites into a safety and efficacy study of a new synthetic donor site dressing. Bilateral donor sites were randomized to receive either a new, synthetic donor site dressing or an impregnated gauze dressing. Wounds were assessed by time to healing, pain, and patient preference. Synthetic dressing wounds were treated 7.9 days compared with 10.2 days for gauze dressing wounds (p < 0.001), and synthetic dressing wounds were more completely epithelialized. Visual analogue pain analysis revealed significantly less donor site pain with synthetic dressing (2.94) versus gauze dressing (4.64) (p < 0.001). Synthetic dressing had fewer treatment-related adverse experiences than gauze dressing (2 vs 7) and was judged by recipients to be superior to gauze dressing in comfort, pain relief, cosmetic appeal, ease of ambulation, and overall acceptance.

Effects of cyclosporine A pretreatment of deceased organ donors on kidney graft function (Cis-A-rein): study protocol for a randomized controlled trial.

PubMed

Orban, Jean-Christophe; Fontaine, Eric; Cassuto, Elisabeth; Baumstarck, Karine; Leone, Marc; Constantin, Jean-Michel; Ichai, Carole

2018-04-17

Renal transplantation represents the treatment of choice of end-stage kidney disease. Delayed graft function (DGF) remains the most frequent complication after this procedure, reaching more than 30%. Its prevention is essential as it impedes early- and long-term prognosis of transplantation. Numerous pharmacological interventions aiming to prevent ischemia-reperfusion injuries failed to reduce the rate of DGF. We hypothesize that cyclosporine as an early preconditioning procedure in donors would be associated with decreased DGF. The Cis-A-rein study is an investigator-initiated, prospective, multicenter, double-blind, randomized, controlled study performed to assess the effects of a donor preconditioning with cyclosporine A on kidney grafts function in transplanted patients. After randomization, a brain dead donor will receive 2.5 mg kg -1 of cyclosporine A or the same volume of 5% glucose solution. The primary objective is to compare the rate of DGF, defined as the need for at least one dialysis session within the 7 days following transplantation, between both groups. The secondary objectives include rate of slow graft function, mild and severe DGF, urine output and serum creatinine during the first week after transplantation, rate of primary graft dysfunction, renal function and mortality at 1 year. The sample size (n = 648) was determined to obtain 80% power to detect a 10% difference for rate of DGF at day 7 between the two groups (30% of the patients in the placebo group and 20% of the patients in the intervention group). Delayed graft function is a major issue after renal transplantation, impeding long-term prognosis. Cyclosporine A pretreatment in deceased donors could improve the outcome of patients after renal transplantation. ClinicalTrials.gov, ID: NCT02907554 Registered on 20 September 2016.

A Prospective Randomized Trial of the Efficacy of Fibrin Glue, Triamcinolone Acetonide, and Quilting Sutures in Seroma Prevention after Latissimus Dorsi Breast Reconstruction.

PubMed

Hart, Alexandra M; Duggal, Clarie; Pinell-White, Ximena; Losken, Albert

2017-04-01

Donor-site seroma is the most common complication following latissimus dorsi flap breast reconstruction. Various agents and techniques have attempted to minimize seroma formation. The purpose of this study was to compare the efficacy of different products and quilting sutures at seroma prevention. This is a single-center, double-blinded, randomized, controlled trial of a consecutive series of breast cancer patients (n = 96) undergoing latissimus dorsi flap reconstruction performed by a single surgeon. Patients were randomized to receive (1) fibrin glue (Tisseel) (n = 23), (2) triamcinolone acetonide (n = 26), or (3) normal saline (control) (n = 27) sprayed into the donor site. The fourth arm included donor-site quilting sutures (n = 20). Outcomes included seroma, drain output, and days to last drain removal. Drain removal was standardized at less than 30 cc/day. All groups were matched evenly without differences in risk, procedures, or complications. The overall seroma rate was 31.3 percent (n = 30). The quilting group had significantly less drainage for weeks 1 (p = 0.006) and 2 (p = 0.050) postoperatively. Quilting statistically reduced the incidence of seromas to 5.0 percent (n = 1; p = 0.038) compared with other groups (control, 34.5 percent; fibrin, 27.6 percent; and triamcinolone, 37.6 percent). Drains were removed 10 days earlier with quilting (control, 35.5 days; fibrin, 39.5 days; triamcinolone, 37.4 days; and quilting, 25.8 days; p = 0.001). The incidence of all other complications was similar between groups. The use of quilting donor sites significantly decreases the incidence of donor-site seromas and leads to earlier drain removal following latissimus dorsi flap reconstruction and maintains a low complication profile. Therapeutic, II.

Aspirin administered to women at 100 mg every other day produces less platelet inhibition than aspirin administered at 81 mg per day: implications for interpreting the women's health study.

PubMed

Swaim, Lisa; Hillman, Robert S

2009-07-01

We aimed to determine the relative level of platelet inhibition achieved with low-dose aspirin (81 mg daily) compared with a very low-dose (100 mg every other day). The Womens Health Study (WHS) found that a dose of 100 mg every other day of aspirin provided protection against stroke as primary prophylaxis, but not myocardial infarction. In the United States, the most commonly prescribed dose of aspirin for primary prophylaxis is 81 mg per day. As a result, it is important to know whether these doses are equivalent before extrapolating the results of the WHS to women in the U.S. To achieve this goal, we have studied the effects of these two dosing regimens on platelet function in healthy women meeting the WHS inclusion criteria using a randomized design. We enrolled 49 healthy female volunteers and used a sequential, crossover design to compare the two regimens. The participants received a 17-day course of each aspirin-dosing regimen separated by a 7-day washout period. The degree of platelet inhibition was measured on days 14-17 of each dosing regimen using a point-of-care platelet function assay utilizing arachidonic acid to activate platelets (VerifyNow-Aspirin). Participants platelet response, expressed as Aspirin Response Unit (ARU) attained a significantly greater level of platelet inhibition on days 14-17 while taking aspirin 81 mg daily compared to aspirin 100 mg every other day (31.3% vs. 12.7%, P < 0.0001) with mean +/- SD ARU values of 445 +/- 50 and 570 +/- 68, P < 0.0001. Significantly more daily readings in participants were >or=550 ARU, a value correlated with clinical outcomes in several studies, with the 100 mg every other day regimen (72.0% vs. 6.4% with 81 mg daily, P < 0.0001), and this alternate-day regimen also resulted in more day-to-day variability in platelet function (P = 0.0002). We found significantly less inhibition of platelet function with the dose used in the WHS than the usual U.S. dose. We observed that the degree of platelet inhibition was significantly less with aspirin 100 mg every other day compared with aspirin 81 mg daily, suggesting that results of the Women's Health Study may have underestimated both the efficacy and toxicity of aspirin as it is commonly administered. These data need to be considered when developing recommendations about the use of aspirin in the primary prevention of cardiovascular disease in women.

Elevated expression of platelet-derived chemokines in patients with antiphospholipid syndrome.

PubMed

Patsouras, Markos D; Sikara, Marina P; Grika, Eleftheria P; Moutsopoulos, Haralampos M; Tzioufas, Athanasios G; Vlachoyiannopoulos, Panayiotis G

2015-12-01

Platelet factor 4 tetramers (CXCL4 chemokine) form complexes with β2glycoprotein I (β2GPI), recognized by anti-β2GPI antibodies leading to platelet activation in antiphospholipid syndrome (APS), either primary (PAPS) or secondary (SAPS). Increased plasma levels of CXCL4 may favor this process; therefore we measured plasma levels of CXCL4, a CXCL4 variant (CXCL4L1) and as controls, platelet-derived chemokines CXCL7 (NAP-2) and CCL5 (RANTES), in APS, and disease controls such as patients with systemic lupus erythematosus (SLE) coronary artery disease (CAD) and healthy donors (HDs). Plasma samples and platelets were isolated from patients with APS (n = 87), SLE (n = 29), CAD (n = 14) and 54 HDs. Plasma levels of CXCL4, CXCL4L1, CXCL7 and CCL5 as well as intracellular platelet CXCL4 and CXCL4L1 were measured using ELISA. Platelet CXCL4 and CXCL4L1 RNA levels were determined by RT-PCR. CXCL4, CXCL7 (NAP-2) and CCL5 (RANTES) plasma levels were significantly higher in patients with APS compared to both control groups (SLE, CAD) and HDs. CXCL4L1 plasma levels were also significantly higher in APS than in SLE and HDs, but lower from that of CAD patients. Statistically significant concordance was detected between CXCL4 and CXCL7 (p < 0.0001) or CCL5 (p < 0.0001) plasma levels in patients with APS, either PAPS or SAPS. CXCL4L1 plasma levels were inversely correlated with CXCL4 (P = 0.0027), CXCL7 (p = 0.012) and CCL5 (p = 0.023) in PAPS and positively with CXCL4 (p = 0.0191), CCL5 (p < 0.0001) and CXCL7 (P < 0.0001), in SAPS. Levels of CXCL4, CXCL4L1, CXCL7 and CCL5 were divided in "high" (exceeding a level defined as the mean of HDs and 3 SD) and "low" (below this level); The "CXCL4L1 high" group was characterized by increased IgG aCL, (p = 0.0215), double antibody positivity (either aCL or anti-β2GPI plus LA), (p = 0.0277), triple antibody positivity (aCL plus anti-β2GPI plus LA), (p = 0.0073) and thrombocytopenia (p = 0.0061), as well as with at least 1 thrombotic event or the last 5 years (p = 0.0001), or more than 3 thrombotic events ever (p = 0.0151). Chemokines associated with platelet activation and immune cell chemotaxis were found to be elevated in APS patients' plasma and may contribute to the pathogenesis of the syndrome. High CXCL4L1 plasma levels are associated with the clinical expression of APS and should be prospectively evaluated as a biomarker. Copyright © 2015. Published by Elsevier Ltd.

Donor understanding and attitudes about current and potential deferral criteria for high-risk sexual behavior.

PubMed

Goldman, Mindy; Yi, Qi-Long; Ye, Xibiao; Tessier, Lorna; O'Brien, Sheila F

2011-08-01

Few donor criteria are as contentious as the deferral of men who have had sex with men (MSM). We performed an anonymous donor survey to determine attitudes toward current screening and the feasibility and acceptability of adoption of alternate donor criteria for MSM. Donors who had successfully donated to Canadian Blood Services were randomly mailed an anonymous questionnaire several weeks after donation; there were 40,000 donors sampled, evenly split between first-time and repeat donors. The response rate was 45.5%. The vast majority of donors found the current screening questions and clinic environment acceptable. Attention to clinic educational materials was poor. A total of 53% felt that the MSM criteria should be changed; many were supportive of criteria based on specific behaviors rather than a period of abstinence. Gender-neutral questions such as number of sexual partners would result in deferral of large numbers of donors. Many donors would support a change in MSM deferral policy. Implementation of strategies based on donor attention to additional material would be challenging. Universal use of simple gender-neutral questions would result in very high donor loss and are therefore not an acceptable option. The acceptability and feasibility of various screening approaches should be explored further with both donors and advocacy groups. © 2011 American Association of Blood Banks.

Reversal of Apixaban Induced Alterations in Hemostasis by Different Coagulation Factor Concentrates: Significance of Studies In Vitro with Circulating Human Blood

PubMed Central

Arellano-Rodrigo, Eduardo; Roquer, Jaume; Reverter, Joan Carles; Sanz, Victoria Veronica; Molina, Patricia; Lopez-Vilchez, Irene; Diaz-Ricart, Maribel; Galan, Ana Maria

2013-01-01

Apixaban is a new oral anticoagulant with a specific inhibitory action on FXa. No information is available on the reversal of the antihemostatic action of apixaban in experimental or clinical settings. We have evaluated the effectiveness of different factor concentrates at reversing modifications of hemostatic mechanisms induced by moderately elevated concentrations of apixaban (200 ng/ml) added in vitro to blood from healthy donors (n = 10). Effects on thrombin generation (TG) and thromboelastometry (TEM) parameters were assessed. Modifications in platelet adhesive, aggregating and procoagulant activities were evaluated in studies with blood circulating through damaged vascular surfaces, at a shear rate of 600 s−1. The potential of prothrombin complex concentrates (PCCs; 50 IU/kg), activated prothrombin complex concentrates (aPCCs; 75 IU/kg), or activated recombinant factor VII (rFVIIa; 270 μg/kg), at reversing the antihemostatic actions of apixaban, were investigated. Apixaban interfered with TG kinetics. Delayed lag phase, prolonged time to peak and reduced peak values, were improved by the different concentrates, though modifications in TG patterns were diversely affected depending on the activating reagents. Apixaban significantly prolonged clotting times (CTs) in TEM studies. Prolongations in CTs were corrected by the different concentrates with variable efficacies (rFVIIa≥aPCC>PCC). Apixaban significantly reduced fibrin and platelet interactions with damaged vascular surfaces in perfusion studies (p<0.05 and p<0.01, respectively). Impairments in fibrin formation were normalized by the different concentrates. Only rFVIIa significantly restored levels of platelet deposition. Alterations in hemostasis induced by apixaban were variably compensated by the different factor concentrates investigated. However, effects of these concentrates were not homogeneous in all the tests, with PCCs showing more efficacy in TG, and rFVIIa being more effective on TEM and perfusion studies. Our results indicate that rFVIIa, PCCs and aPCCs have the potential to restore platelet and fibrin components of the hemostasis previously altered by apixaban. PMID:24244342

Role of nitric oxide in long-term potentiation of the rat medial vestibular nuclei.

PubMed

Grassi, S; Pettorossi, V E

2000-01-01

In rat brainstem slices, we investigated the role of nitric oxide in long-term potentiation induced in the ventral portion of the medial vestibular nuclei by high-frequency stimulation of the primary vestibular afferents. The nitric oxide scavenger [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide ] and the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester were administered before and after induction of potentiation. Both drugs completely prevented long-term potentiation, whereas they did not impede the potentiation build-up, or affect the already established potentiation. These results demonstrate that the induction, but not the maintenance of vestibular long-term potentiation, depends on the synthesis and release into the extracellular medium of nitric oxide. In addition, we analysed the effect of the nitric oxide donor sodium nitroprusside on vestibular responses. Sodium nitroprusside induced long-term potentiation, as evidenced through the field potential enhancement and unit peak latency decrease. This potentiation was impeded by D, L-2-amino-5-phosphonopentanoic acid, and was reduced under blockade of synaptosomal platelet-activating factor receptors by ginkgolide B and group I metabotropic glutamate receptors by (R,S)-1-aminoindan-1, 5-dicarboxylic acid. When reduced, potentiation fully developed following the washout of antagonist, demonstrating an involvement of platelet-activating factor and group I metabotropic glutamate receptors in its full development. Potentiation induced by sodium nitroprusside was also associated with a decrease in the paired-pulse facilitation ratio, which persisted under ginkgolide B, indicating that nitric oxide increases glutamate release independently of platelet-activating factor-mediated presynaptic events. We suggest that nitric oxide, released after the activation of N-methyl-D-aspartate receptors, acts as a retrograde messenger leading to an enhancement of glutamate release to a sufficient level for triggering potentiation. Once the synaptic efficacy has changed, it becomes a long-lasting phenomenon only through a subsequent action of platelet-activating factor.

Fecal microbiota transplant from a rational stool donor improves hepatic encephalopathy: A randomized clinical trial.

PubMed

Bajaj, Jasmohan S; Kassam, Zain; Fagan, Andrew; Gavis, Edith A; Liu, Eric; Cox, I Jane; Kheradman, Raffi; Heuman, Douglas; Wang, Jessica; Gurry, Thomas; Williams, Roger; Sikaroodi, Masoumeh; Fuchs, Michael; Alm, Eric; John, Binu; Thacker, Leroy R; Riva, Antonio; Smith, Mark; Taylor-Robinson, Simon D; Gillevet, Patrick M

2017-12-01

Recurrent hepatic encephalopathy (HE) is a leading cause of readmission despite standard of care (SOC) associated with microbial dysbiosis. Fecal microbiota transplantation (FMT) may improve dysbiosis; however, it has not been studied in HE. We aimed to define whether FMT using a rationally derived stool donor is safe in recurrent HE compared to SOC alone. An open-label, randomized clinical trial with a 5-month follow-up in outpatient men with cirrhosis with recurrent HE on SOC was conducted with 1:1 randomization. FMT-randomized patients received 5 days of broad-spectrum antibiotic pretreatment, then a single FMT enema from the same donor with the optimal microbiota deficient in HE. Follow-up occurred on days 5, 6, 12, 35, and 150 postrandomization. The primary outcome was safety of FMT compared to SOC using FMT-related serious adverse events (SAEs). Secondary outcomes were adverse events, cognition, microbiota, and metabolomic changes. Participants in both arms were similar on all baseline criteria and were followed until study end. FMT with antibiotic pretreatment was well tolerated. Eight (80%) SOC participants had a total of 11 SAEs compared to 2 (20%) FMT participants with SAEs (both FMT unrelated; P = 0.02). Five SOC and no FMT participants developed further HE (P = 0.03). Cognition improved in the FMT, but not the SOC, group. Model for End-Stage Liver Disease (MELD) score transiently worsened postantibiotics, but reverted to baseline post-FMT. Postantibiotics, beneficial taxa, and microbial diversity reduction occurred with Proteobacteria expansion. However, FMT increased diversity and beneficial taxa. SOC microbiota and MELD score remained similar throughout. FMT from a rationally selected donor reduced hospitalizations, improved cognition, and dysbiosis in cirrhosis with recurrent HE. (Hepatology 2017;66:1727-1738). © 2017 by the American Association for the Study of Liver Diseases.

Comparison of two apheresis systems for the collection of CD14+ cells intended to be used in dendritic cell culture.

PubMed

Strasser, Erwin F; Berger, Thomas G; Weisbach, Volker; Zimmermann, Robert; Ringwald, Jürgen; Schuler-Thurner, Beatrice; Zingsem, Jürgen; Eckstein, Reinhold

2003-09-01

Monocytes collected by leukapheresis are increasingly used for dendritic cell (DC) culture in cell factories suitable for DC vaccination in cancer. Using modified MNC programs on two apheresis systems (Cobe Spectra and Fresenius AS.TEC204), leukapheresis components collected from 84 patients with metastatic malignant melanoma and from 31 healthy male donors were investigated. MNCs, monocytes, RBCs, and platelets (PLTs) in donors and components were analyzed by cell counters, WBC differential counts, and flow cytometry. In 5-L collections, Astec showed better results regarding monocyte collection rates (11.0 vs. 7.4 x 10(6)/min, p = 0.04) and efficiencies (collection efficiency, 51.9 vs. 31.9%; p < 0.001). Both devices resulted in monocyte yields at an average of 1 x 10(9) (donors) and 2.5 x 10(9) (patients), whereas Astec components contained high residual RBCs. Compared to components with low residual PLTs, high PLT concentration resulted in higher monocyte loss (48 vs. 20%, p < 0.0001) before DC culture. The Astec is more efficient in 5-L MNC collections compared to the Spectra. Components with high residual PLTs result in high MNC loss by purification procedures. Thus, optimizing MNC programs is essential to obtain components with high MNC yields and low residual cells as prerequisite for high DC yields.

Outcomes and healthcare utilization in children and young adults with aplastic anemia: A multiinstitutional analysis.

PubMed

Gupta, Ashish; Fu, Pingfu; Hashem, Hasan; Vatsayan, Anant; Shein, Steven; Dalal, Jignesh

2017-12-01

Aplastic anemia is a bone marrow failure syndrome with high mortality affecting children and young adults. Although current treatment guidelines recommend hematopoietic stem cell transplant (HCT) for patients with matched sibling donors, outcomes with alternate donor options have been improving. We analyzed a validated multiinstitutional pediatric cohort using one of the largest pediatric and young adult database, the Pediatric Health Information System, for patients diagnosed with aplastic anemia (AA) from 2006 to 2015. Outcomes with upfront and salvage transplants were analyzed along with healthcare utilization. Among 2,169 patients in the study period, almost 20% underwent HCT, while others received immunosuppressive therapy. In a multivariate model, there was no significant difference in mortality with upfront or salvage transplants (odds ratio [OR] 1.24, 95% confidence interval [CI] 0.6-2.58, P = 0.567), while every platelet transfusion was associated with higher mortality (OR 1.37, 95% CI 1.12-1.67, P = 0.002). Healthcare utilization was significantly higher in salvage transplants requiring frequent hospitalization and transfusion requirements. Treatment mortality and graft failure rates were significantly reduced in the salvage transplant group in recent years (2011-2015 as compared to 2006-2010). As outcomes with HCT continue to improve in severe AA, transplant with good alternate donors should be considered upfront in children and young adults. © 2017 Wiley Periodicals, Inc.

Transfusion Medicine and Molecular Genetic Methods

PubMed Central

Saleh, Rozieyati Mohamed; Zefarina, Zulkafli; Che Mat, Nor Fazila; Chambers, Geoffrey Keith; Edinur, Hisham Atan

2018-01-01

Transfusion procedures are always complicated by potential genetic mismatching between donor and recipient. Compatibility is determined by several major antigens, such as the ABO and Rhesus blood groups. Matching for other blood groups (Kell, Kidd, Duffy, and MNS), human platelet antigens, and human leukocyte antigens (HLAs) also contributes toward the successful transfusion outcomes, especially in multitransfused or highly immunized patients. All these antigens of tissue identity are highly polymorphic and thus present great challenges for finding suitable donors for transfusion patients. The ABO blood group and HLA markers are also the determinants of transplant compatibility, and mismatched antigens will cause graft rejection or graft-versus-host disease. Thus, a single and comprehensive registry covering all of the significant transfusion and transplantation antigens is expected to become an important tool in providing an efficient service capable of delivering safe blood and quickly locating matching organs/stem cells. This review article is intended as an accessible guide for physicians who care for transfusion-dependent patients. In particular, it serves to introduce the new molecular screening methods together with the biology of these systems, which underlies the tests. PMID:29899883

Options to avoid the second surgical site: a review of literature.

PubMed

Ramachandra, Srinivas Sulugodu; Rana, Ritu; Reetika, Singhal; Jithendra, K D

2014-09-01

As esthetics gain importance, periodontal plastic surgical procedures involving soft tissue grafts are becoming commoner both around natural teeth as well as around implants. Periodontal soft tissue grafts are primarily used for the purpose of root coverage and in pre-prosthetic surgery to thicken a gingival site or to improve the crestal volume. Soft tissue grafts are usually harvested from the palate. Periodontal plastic surgical procedures involving soft tissue grafts harvested from the palate have two surgical sites; a recipient site and another donor site. Many patients are apprehensive about the soft tissue graft procedures, especially the creation of the second/donor surgical site in the palate. In the past decade, newer techniques and products have emerged which provide an option for the periodontist/patient to avoid the second surgical site. MucoMatrixX, Alloderm(®), Platelet rich fibrin, Puros(®) Dermis and Mucograft(®) are the various options available to the practicing periodontist to avoid the second surgical site. Use of these soft tissue allografts in an apprehensive patient would decrease patient morbidity and increase patient's acceptance towards periodontal plastic surgical procedures.