Bloodcurdling movies and measures of coagulation: Fear Factor crossover trial

PubMed Central

Nemeth, Banne; Scheres, Luuk J J; Lijfering, Willem M

2015-01-01

Objective To assess whether, as has been hypothesised since medieval times, acute fear can curdle blood. Design Crossover trial. Setting Main meeting room of Leiden University’s Department of Clinical Epidemiology, the Netherlands, converted to a makeshift cinema. Participants 24 healthy volunteers aged ≤30 years recruited among students, alumni, and employees of the Leiden University Medical Center: 14 were assigned to watch a frightening (horror) movie followed by a non-threatening (educational) movie and 10 to watch the movies in reverse order. The movies were viewed more than a week apart at the same time of day and both lasted approximately 90 minutes. Main outcome measures The primary outcome measures were markers, or “fear factors” of coagulation activity: blood coagulant factor VIII, D-dimer, thrombin-antithrombin complexes, and prothrombin fragments 1+2. The secondary outcome was participant reported fear experienced during each movie using a visual analogue fear scale. Results All participants completed the study. The horror movie was perceived to be more frightening than the educational movie on a visual analogue fear scale (mean difference 5.4, 95% confidence interval 4.7 to 6.1). The difference in factor VIII levels before and after watching the movies was higher for the horror movie than for the educational movie (mean difference of differences 11.1 IU/dL (111 IU/L), 95% confidence interval 1.2 to 21.0 IU/dL). The effect of either movie on levels of thrombin-antithrombin complexes, D-dimer, and prothrombin fragments 1+2 did not differ. Conclusion Frightening (in this case, horror) movies are associated with an increase of blood coagulant factor VIII without actual thrombin formation in young and healthy adults. Trial registration ClinicalTrials.gov NCT02601053. PMID:26673787

Effects of In Vitro Hemodilution, Hypothermia and rFVIIa Addition on Coagulation in Human Blood

DTIC Science & Technology

2012-03-30

primary fluids used by many trauma units and the US Army for pre-hospital resuscitation [17]. HX, a hetastarch-based product in a balanced electro...and has been associated with dilution of coagulation factors and hypothermia. Recombinant activated Factor VII (rFVIIa) has been used, often as a...of rFVIIa results in an enhancement of thrombin generation on the platelet surface at the site of injury independent of the presence of Factor VIII

Increased thromboplastic potential in diabetes: a multifactorial phenomenon.

PubMed

Landgraf-Leurs, M M; Ladik, T; Smolka, B; Bock, T; Schramm, W; Spannagl, M; Landgraf, R

1987-07-01

Coagulation parameters, platelet aggregation, and thromboxane production as well as metabolic parameters were measured in 31 diabetic patients, 12 without and 19 with clinically manifest late complications, and in 14 healthy control subjects. Spontaneous in vitro aggregation as well as ADP, collagen, and arachidonic acid induced aggregation were higher in both groups of diabetic patients, without an increase in thromboxane B2 production. In diabetic patients with late complications an increase in fibrinogen, fibrinogen cyanogen bromide peptide, factor VIII related antigen, C1-esterase inhibitor, and antithrombin III was observed in comparison to healthy subjects. Fibrinogen, C1-esterase inhibitor, and factor VIII related antigen were already elevated in diabetic patients without clinically manifest late vascular complications. No strict correlations were found between serum glucose, glycosylated hemoglobin, and glycosylated albumin, on the one hand, and coagulation promoting or inhibiting factors, aggregation or thromboxane B2 production, on the other, in either control or diabetic subjects. Also no correlations existed between the coagulation parameters and the aggregation results. In vitro incubation of pooled normal plasma with different glucose concentrations had no influence on the methods by which the coagulation parameters were measured. These data indicate that rather early in the diabetic state many changes take place in different phases of the thrombostatic process, all resulting in an increased hemostatic diathesis.

Coagulation and oxidative stress plasmatic levels in a type 2 diabetes population.

PubMed

Barillari, Giovanni; Fabbro, Elisabetta; Pasca, Samantha; Bigotto, Enrico

2009-06-01

Type 2 diabetes mellitus (DM2) is a metabolic disorder characterized by relative insulin deficiency, insulin resistance and hyperglycemia. DM2 improperly managed can cause severe complications such as renal failure, blindness or arterial disease. In addition to serious complications due to DM2, in the past 20 years, several studies have demonstrated the association between DM2, insulin resistance and prothrombotic risk. In our study, we wanted to evaluate the correlation between coagulation factor levels, oxidative plasmatic levels and DM2. We considered 20 DM2 patients (65% women and 35% men), 40-65 years of age, who had a BMI between 25 and 40 kg/m2 and followed a diet with or without oral antidiabetic treatment and 20 controls, blood donors, 15 men (75%) and five women (25%), who had a BMI between 25 and 40 kg/m2 and their age was between 40 and 65 years. Plasmatic levels of oxidative stress markers (tumor necrosis factor-alpha, nitrotyrosine, oxidized low-density lipoprotein) and coagulation markers (factors VII, VIII, IX, XI, XII, antithrombin III and fibrinogen) of both populations were analyzed following statistic criteria. The analyzed data of this study related to oxidative stress and coagulation factors proved that the differences observed between diabetic patients and controls were not statistically significant (P < 0.05) for tumor necrosis factor-alpha, nitrotyrosine, oxidized low-density lipoprotein, factor VII and factor XI; conversely for factor VIII, factor IX, factor XII, antithrombin III and fibrinogen, the results gave a difference statistically significant (P < 0.01). In patients with DM2, factor VIII increased from 79 to 103%, factor IX from 88 to 103%, factor XII from 87 to 105% and finally, antithrombin III from 81 to 103%. Different results between literature and our study could be due to fact that the patients considered were in the early stage of diabetes when endothelial damage is absent and vascular complications are not clinically expressed. In this study, it is still shown that DM2 is a multifactor disease and its physiopathologic mechanisms are not completely known today.

Rare coagulation disorders: fibrinogen, factor VII and factor XIII.

PubMed

de Moerloose, P; Schved, J-F; Nugent, D

2016-07-01

Rare coagulation disorders (RCDs) include the inherited deficiencies of fibrinogen, factor (F) II, FV, combined FV and VIII, FVII, FX, combined FVII and X, FXI, FXIII and combined congenital deficiency of vitamin K-dependent factors (VKCFDs). Despite their rarity, a deep comprehension of all these disorders is essential to really understand haemostasis. Indeed, even if they share some common features each RCD has some particularity which makes it unique. In this review, we focus on three disorders: fibrinogen, FVII and FXIII. © 2016 John Wiley & Sons Ltd.

Bloodcurdling movies and measures of coagulation: Fear Factor crossover trial.

PubMed

Nemeth, Banne; Scheres, Luuk J J; Lijfering, Willem M; Rosendaal, Frits R

2015-12-16

To assess whether, as has been hypothesised since medieval times, acute fear can curdle blood. Crossover trial. Main meeting room of Leiden University's Department of Clinical Epidemiology, the Netherlands, converted to a makeshift cinema. 24 healthy volunteers aged ≤30 years recruited among students, alumni, and employees of the Leiden University Medical Center: 14 were assigned to watch a frightening (horror) movie followed by a non-threatening (educational) movie and 10 to watch the movies in reverse order. The movies were viewed more than a week apart at the same time of day and both lasted approximately 90 minutes. The primary outcome measures were markers, or "fear factors" of coagulation activity: blood coagulant factor VIII, D-dimer, thrombin-antithrombin complexes, and prothrombin fragments 1+2. The secondary outcome was participant reported fear experienced during each movie using a visual analogue fear scale. All participants completed the study. The horror movie was perceived to be more frightening than the educational movie on a visual analogue fear scale (mean difference 5.4, 95% confidence interval 4.7 to 6.1). The difference in factor VIII levels before and after watching the movies was higher for the horror movie than for the educational movie (mean difference of differences 11.1 IU/dL (111 IU/L), 95% confidence interval 1.2 to 21.0 IU/dL). The effect of either movie on levels of thrombin-antithrombin complexes, D-dimer, and prothrombin fragments 1+2 did not differ. Frightening (in this case, horror) movies are associated with an increase of blood coagulant factor VIII without actual thrombin formation in young and healthy adults. Trial registration ClinicalTrials.gov NCT02601053. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Pelvic adhesion and gonadotropin-releasing hormone analogue: effects of triptorelin acetate depot on coagulation and fibrinolytic activities.

PubMed

Di Nardo, Maria Antonietta; Annunziata, Maria Laura; Ammirabile, Massimiliano; Di Minno, Matteo Nicola Dario; Ruocco, Anna Lilia; De Falco, Marianna; Di Lieto, Andrea

2012-06-01

The study investigated the impact of gonadotropin-releasing hormone analogue (GnRH-a) on coagulation and fibrinolytic activities and its effectiveness in the prevention of pelvic adhesion after myomectomy. Thirty-two infertile women underwent myomectomy followed by adhesion evaluation surgery with a second-look laparoscopy. Before myomectomy, 15 women were treated with triptorelin acetate for 3 months and 17 received no treatment. Plasminogen activator inhibitor (PAI), thrombin activatable fibrinolysis inhibitor (TAFI), protein C (PC), plasminogen, α2-antiplasmin were determined by enzyme-linked immunosorbent assays and the activity of coagulation factors V and VIII by coagulometric methods. Patients treated with GnRH-a showed significant decrease in PAI, TAFI, factors V, and VIII (P < .05) and increased PC (P < .05), but no significant change in plasminogen and α2-antiplasmin levels compared with control group. The incidence, extent, and severity of adhesions were significantly lower in GnRH-a-treated patients compared with control group (P < .05), suggesting a possible critical role of the GnRH-a therapy in preventing postoperative adhesion development.

Human extrahepatic portal vein obstruction correlates with decreased factor VII and protein C transcription but increased hepatocyte proliferation.

PubMed

Chiu, Bill; Melin-Aldana, Hector; Superina, Riccardo A

2007-10-01

A 3-year-old girl developed extrahepatic portal vein obstruction (EHPVO) after a liver transplant. She had sequelae of portal hypertension that required another transplantation. The circumstances allowed for comparison of liver-dependent coagulation factor production between the second donor liver and the explanted liver with EHPVO. Liver samples from the explanted first graft and the second transplant were obtained. Fresh tissue was used to perform reverse transcription-polymerase chain reaction with primers against factors V, VII, as well as VIII, protein C, and paraffin-embedded sections for hepatocyte proliferation using Ki-67 antibody as well as for apoptosis using TUNEL assay. The transcription of factor VII and that of protein C were decreased in the explant as compared with the newly transplanted liver (factor VII, 77% of the donor; protein C, 88% of the donor). The transcription of factor V and that of factor VIII were unchanged. The explant had a greater percentage of proliferating hepatocytes than the new organ (0.85% +/- 0.75% vs 0.11% +/- 0.21%). The percentage of apoptotic cells was similar between the 2 livers (0.09% +/- 0.13% vs 0.09% +/- 0.13%). Idiopathic EHPVO is associated with a reduction in liver-dependent coagulation factor transcription and an increase in hepatocyte proliferation. Portal blood flow deprivation alters hepatic homeostasis and initiates mechanisms that attempt to restore liver-dependent coagulation factors.

B-domain deleted recombinant factor VIII formulation and stability.

PubMed

Osterberg, T; Fatouros, A; Neidhardt, E; Warne, N; Mikaelsson, M

2001-04-01

B-domain deleted recombinant factor VIII (BDDrFVIII) is a deletion form of human coagulation factor VIII. A lyophilized formulation of highly purified BDDrFVIII has been developed that does not require the use of blood-derived products such as human serum albumin (HSA). By avoiding the use of blood-derived products, the BDDrFVIII formulation minimizes the risk of transmitting blood-borne pathogens that may be present in plasma-derived factor VIII or in other recombinant factor VIII products that contain HSA in their formulation. Upon reconstitution with saline (4 mL), the composition of the reconstituted product (62.5 to 250 IU/mL BDDrFVIII) is 18 mg/mL sodium chloride, 3.0 mg/mL sucrose, 1.5 mg/mL L-histidine, 0.25 mg/mL calcium chloride dihydrate, and 0.1 mg/mL polysorbate 80. The optimal combination of these excipients in the lyophilized BDDrFVIII formulation provides long-term stability, as measured by a variety of analytical methods. The formulation preserves factor VIII activity of lyophilized BDDrFVIII during storage for at least 24 months at 8 degrees C, and for up to 6 months at room temperature (25 degrees C). The reconstituted product retains its factor VIII potency for at least 100 hours at 25 degrees C, which would allow it to be continuously administered via an infusion pump, assuming the product is handled under aseptic conditions.

Human parvovirus B19 infection in hemophiliacs first infused with two high-purity, virally attenuated factor VIII concentrates.

PubMed

Azzi, A; Ciappi, S; Zakvrzewska, K; Morfini, M; Mariani, G; Mannucci, P M

1992-03-01

Human parvovirus B19 can be transmitted by coagulation factor concentrates and is highly resistant to virucidal methods. To evaluate whether the additional removal of virus by chromatographic methods during the manufacture of high-purity concentrates reduces the risk of B19 transmission, we have prospectively evaluated the rate of anti-B19 seroconversion in two groups of susceptible (anti-B19 negative) hemophiliacs infused with high-purity, heated (pasteurized) or solvent-detergent-treated factor VIII concentrates. Both products infected a relatively high proportion of patients (nine of 20).

Biological and analytical variations of 16 parameters related to coagulation screening tests and the activity of coagulation factors.

PubMed

Chen, Qian; Shou, Weiling; Wu, Wei; Guo, Ye; Zhang, Yujuan; Huang, Chunmei; Cui, Wei

2015-04-01

To accurately estimate longitudinal changes in individuals, it is important to take into consideration the biological variability of the measurement. The few studies available on the biological variations of coagulation parameters are mostly outdated. We confirmed the published results using modern, fully automated methods. Furthermore, we added data for additional coagulation parameters. At 8:00 am, 12:00 pm, and 4:00 pm on days 1, 3, and 5, venous blood was collected from 31 healthy volunteers. A total of 16 parameters related to coagulation screening tests as well as the activity of coagulation factors were analyzed; these included prothrombin time, fibrinogen (Fbg), activated partial thromboplastin time, thrombin time, international normalized ratio, prothrombin time activity, activated partial thromboplastin time ratio, fibrin(-ogen) degradation products, as well as the activity of factor II, factor V, factor VII, factor VIII, factor IX, and factor X. All intraindividual coefficients of variation (CVI) values for the parameters of the screening tests (except Fbg) were less than 5%. Conversely, the CVI values for the activity of coagulation factors were all greater than 5%. In addition, we calculated the reference change value to determine whether a significant difference exists between two test results from the same individual. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Chromogenic Factor VIII Assays for Improved Diagnosis of Hemophilia A.

PubMed

Rodgers, Susan; Duncan, Elizabeth

2017-01-01

Hemophilia A is an inherited bleeding disorder caused by a reduced level of factor VIII coagulant activity (FVIII:C) in blood. Bleeding episodes may occur spontaneously in the severe form of hemophilia or after trauma in the milder forms. It is important that patients are diagnosed correctly, which includes placing them into the correct severity category of the disorder so that appropriate treatment can be given. Diagnosis is made by determination of the amount of FVIII:C in the blood, usually using a one-stage factor VIII:C assay. However, approximately one third of patients with mild or moderate hemophilia will have much lower results by the chromogenic assay, with some of them having normal results by the one-stage assay. The chromogenic factor VIII assay is used in some specialized hemophilia reference centers and is recommended for the diagnosis of mild hemophilia A, as this assay is considered to better reflect the severity status of hemophilia patients than the one-stage assay.

Thromboelastographic evaluation of dogs with congenital portosystemic shunts.

PubMed

Kelley, D; Lester, C; DeLaforcade, A; Webster, C R L

2013-01-01

On plasma-based assays, dogs with congenital portosystemic shunts (CPSS) have changes in serum concentrations of both pro- and anticoagulant proteins, but how these abnormalities affect whole blood coagulation assays (eg, thromboelastography) are unknown. To conduct kaolin-activated thromboelastography (TEG) analysis in dogs with CPSS and to compare TEG coagulation status with clinical presentation, routine serum biochemistry, and plasma-based coagulation tests. Twenty-one client-owned dogs with CPSS confirmed by ultrasound examination or nuclear scintigraphy. In a prospective study, signalment, clinical presentation, TEG analysis, CBC, serum biochemistry, and hemostatic tests (platelet count, prothrombin time [PT], activated partial thromboplastin time [aPTT], quantitative fibrinogen, antithrombin [AT] activity, protein C [PC] activity, d-dimers, and factor VIII activity) were analyzed in dogs with CPSS. Dogs with CPSS had significantly shorter K values and increased angle, maximum amplitude (MA), and G values compared with the reference population. On plasma-based coagulation testing, dogs with CPSS had significantly prolonged PT, lower platelet counts, lower AT and PC activities, and increased d-dimers and factor VIII activity. Evaluation of G value defined 9/21 dogs with CPSS as hypercoagulable. These dogs were more likely to have hepatic encephalopathy (HE) than CPSS dogs that had normal coagulation. TEG analysis detected hemostatic abnormalities consistent with a hypercoagulable state in some dogs with CPSS. The presence of a hypercoagulable state was 40 times more likely in dogs with symptomatic HE. Copyright © 2013 by the American College of Veterinary Internal Medicine.

Prevalence of nucleic acid sequences specific for human parvoviruses, hepatitis A and hepatitis E viruses in coagulation factor concentrates.

PubMed

Modrow, S; Wenzel, J J; Schimanski, S; Schwarzbeck, J; Rothe, U; Oldenburg, J; Jilg, W; Eis-Hübinger, A M

2011-05-01

Due to their high resistance to inactivation procedures, nonenveloped viruses such as parvovirus B19, human bocavirus (HBoV), human parvovirus 4 (PARV4), hepatitis A (HAV) and hepatitis E virus (HEV) pose a particular threat to blood products. Virus transmission to patients treated with blood products presents an additional burden to disease. We determined the frequency and the amount of nucleic acid specific for nonenveloped viruses in recently manufactured preparations of commercial coagulation factor concentrates. At least three different batches of each of 13 different plasma-derived and recombinant coagulation factor products were tested for the presence and the amount of nucleic acid for parvovirus B19, HBoV, human parvovirus 4, hepatitis A virus and HEV by using quantitative polymerase chain reaction. Whereas none of the recombinant products tested positive for any of these viruses, parvovirus B19 DNA with amounts ranging between 2×10(1) and 1.3×10(3) genome equivalents/ml was detected in five plasma-derived products. In addition to parvovirus B19 genotype 1, genotypes 2 and 3 were observed in two batches of a factor VIII/von-Willebrand factor product. In two products (one factor VIII concentrate and one activated prothrombin complex concentrate), a combination of both genotypes 1 and 2 of parvovirus B19 was detected. The data show that nucleic acids from several relevant nonenveloped viruses are not found at detectable levels in coagulation factor concentrates. In some cases, parvovirus B19 DNA was detectable at low levels. Testing of the plasma pools for the full range of parvovirus genotypes is advocated for ensuring product safety. © 2010 The Author(s). Vox Sanguinis © 2010 International Society of Blood Transfusion.

A Drosophila haemocyte-specific protein, hemolectin, similar to human von Willebrand factor.

PubMed Central

Goto, A; Kumagai, T; Kumagai, C; Hirose, J; Narita, H; Mori, H; Kadowaki, T; Beck, K; Kitagawa, Y

2001-01-01

We identified a novel Drosophila protein of approximately 400 kDa, hemolectin (d-Hml), secreted from haemocyte-derived Kc167 cells. Its 11.7 kbp cDNA contains an open reading frame of 3843 amino acid residues, with conserved domains in von Willebrand factor (VWF), coagulation factor V/VIII and complement factors. The d-hml gene is located on the third chromosome (position 70C1-5) and consists of 26 exons. The major part of d-Hml consists of well-known motifs with the organization: CP1-EG1-CP2-EG2-CP3-VD1-VD2-VD'-VD3-VC1-VD"-VD"'-FC1-FC2-VC2-LA1-VD4-VD5-VC3-VB1-VB2-VC4-VC5-CK1 (CP, complement-control protein domain; EG, epidermal-growth-factor-like domain; VB, VC, VD, VWF type B-, C- and D-like domains; VD', VD", VD"', truncated C-terminal VDs; FC, coagulation factor V/VIII type C domain; LA, low-density-lipoprotein-receptor class A domain; CK, cysteine knot domain). The organization of VD1-VD2-VD'-VD3, essential for VWF to be processed by furin, to bind to coagulation factor VIII and to form interchain disulphide linkages, is conserved. The 400 kDa form of d-Hml was sensitive to acidic cleavage near the boundary between VD2 and VD', where the cleavage site of pro-VWF is located. Agarose-gel electrophoresis of metabolically radiolabelled d-Hml suggested that it is secreted from Kc167 cells mainly as dimers. Resembling VWF, 7.9% (305 residues) of cysteine residues on the d-Hml sequence had well-conserved positions in each motif. Coinciding with the development of phagocytic haemocytes, d-hml transcript was detected in late embryos and larvae. Its low-level expression in adult flies was induced by injury at any position on the body. PMID:11563973

Physiological levels of blood coagulation factors IX and X control coagulation kinetics in an in vitro model of circulating tissue factor

NASA Astrophysics Data System (ADS)

Tormoen, Garth W.; Khader, Ayesha; Gruber, András; McCarty, Owen J. T.

2013-06-01

Thrombosis significantly contributes to cancer morbidity and mortality. The mechanism behind thrombosis in cancer may be circulating tissue factor (TF), as levels of circulating TF are associated with thrombosis. However, circulating TF antigen level alone has failed to predict thrombosis in patients with cancer. We hypothesize that coagulation factor levels regulate the kinetics of circulating TF-induced thrombosis. Coagulation kinetics were measured as a function of individual coagulation factor levels and TF particle concentration. Clotting times increased when pooled plasma was mixed at or above a ratio of 4:6 with PBS. Clotting times increased when pooled plasma was mixed at or above a ratio of 8:2 with factor VII-depleted plasma, 7:3 with factor IX- or factor X-depleted plasmas, or 2:8 with factor II-, V- or VIII-depleted plasmas. Addition of coagulation factors VII, X, IX, V and II to depleted plasmas shortened clotting and enzyme initiation times, and increased enzyme generation rates in a concentration-dependent manner. Only additions of factors IX and X from low-normal to high-normal levels shortened clotting times and increased enzyme generation rates. Our results demonstrate that coagulation kinetics for TF particles are controlled by factor IX and X levels within the normal physiological range. We hypothesize that individual patient factor IX and X levels may be prognostic for susceptibility to circulating TF-induced thrombosis.

Positive Feedback Loops for Factor V and Factor VII Activation Supply Sensitivity to Local Surface Tissue Factor Density During Blood Coagulation

PubMed Central

Balandina, A.N.; Shibeko, A.M.; Kireev, D.A.; Novikova, A.A.; Shmirev, I.I.; Panteleev, M.A.; Ataullakhanov, F.I.

2011-01-01

Blood coagulation is triggered not only by surface tissue factor (TF) density but also by surface TF distribution. We investigated recognition of surface TF distribution patterns during blood coagulation and identified the underlying molecular mechanisms. For these investigations, we employed 1), an in vitro reaction-diffusion experimental model of coagulation; and 2), numerical simulations using a mathematical model of coagulation in a three-dimensional space. When TF was uniformly immobilized over the activating surface, the clotting initiation time in normal plasma increased from 4 min to >120 min, with a decrease in TF density from 100 to 0.7 pmol/m2. In contrast, surface-immobilized fibroblasts initiated clotting within 3–7 min, independently of fibroblast quantity and despite a change in average surface TF density from 0.5 to 130 pmol/m2. Experiments using factor V-, VII-, and VIII-deficient plasma and computer simulations demonstrated that different responses to these two TF distributions are caused by two positive feedback loops in the blood coagulation network: activation of the TF–VII complex by factor Xa, and activation of factor V by thrombin. This finding suggests a new role for these reactions: to supply sensitivity to local TF density during blood coagulation. PMID:22004734

Hemophilia and von Willebrand's disease: 2. Management. Association of Hemophilia Clinic Directors of Canada.

PubMed Central

1995-01-01

OBJECTIVE: To present current strategies for the treatment of hemophilia and von Willebrand's disease. OPTIONS: Prophylactic and corrective therapy with hemostatic and adjunctive agents: DDAVP (1-desamino-8-D-arginine vasopressin [desmopressin acetate]), recombinant coagulation products (human Factor VIII and human Factor VIIa) or virally inactivated plasma-derived products (high- or ultra-high-purity human Factor VIII or human Factor VIII concentrate containing von Willebrand factor activity, porcine Factor VIII, high-purity human Factor IX, human prothrombin-complex concentrate, human activated prothrombin-complex concentrate), adjunctive antifibrinolytic agents, topical thrombin and fibrin sealant. The induction of immune tolerance in patients in whom inhibitors develop should also be considered. OUTCOMES: Morbidity and quality of life associated with bleeding and treatment. EVIDENCE: Relevant clinical studies and reports published from 1974 to 1994 were examined. A search was conducted of our reprint files, MEDLINE, citations in the articles reviewed and references provided by colleagues. In the MEDLINE search the following terms were used singly or in combination: "hemophilia," "von Willebrand's disease," "Factor VIII," "Factor IX," "von Willebrand factor," "diagnosis," "management," "home care," "comprehensive care," "inhibitor," "AIDS," "hepatitis," "life expectancy," "complications," "practice guidelines," "consensus statement" and "controlled trial." The in-depth review included only articles written in English from North America and Europe that were relevant to human disease and pertinent to a predetermined outline. The availability of treatment products in Canada was also considered. VALUES: Minimizing morbidity and maximizing functional status and quality of life were given a high value. BENEFITS, HARMS AND COSTS: Proper prophylactic or early treatment with appropriate hemostatic agents minimizes morbidity and functional disability and improves quality of life. Economic gains are realized through the reduction of mortality and morbidity and their associated costs. The patient has a better opportunity to contribute to society through gainful employment and the fulfillment of social roles. Potential harms include HIV infection, hepatitis B, hepatitis C and the development of inhibitor antibodies to clotting-factor concentrates. The risk of viral transmission has been minimized through the development of procedures for the viral inactivation of plasma-derived clotting-factor concentrates and through the use of recombinant coagulation-factor concentrates and other non-plasma-derived hemostatic agents. RECOMMENDATIONS: DDAVP is the drug of choice for patients with mild hemophilia or type 1 or 2 (except 2B) von Willebrand's disease whose response to DDAVP in previous testing has been found to be adequate. Therapeutic blood components of choice include recombinant products and virally inactivated plasma-derived products. In Canada the recommended products are recombinant Factor VIII for hemophilia A, high-purity plasma-derived Factor IX for hemophilia B and plasma-derived Factor VIII concentrates containing adequate von Willebrand factor (e.g., Haemate P) for von Willebrand's disease. Dosages vary according to specific indications. Adjunctive antifibrinolytic agents, topical thrombin and fibrin sealant are useful for the treatment of oral or dental bleeds and localized bleeds in accessible sites. In patients with inhibitor antibodies, high-dose human or porcine Factor VIII is usually effective when the inhibitor titre is less than 5 Bethesda units/mL. In nonresponsive patients, or in those whose inhibitor titre is higher, "bypassing" agents (e.g., activated prothrombin-complex concentrate and recombinant Factor VIIa) are useful. Long-term management may include immune-tolerance induction.VALIDATION: These recommendations were reviewed and approved by the Association of Hemophilia Clinic Directors of Canada (AHCDC) and the Medical and Scientific Advisory Committee of the Canadian Hemophilia Society. No similar consensus statements or practice guidelines are available for comparison. SPONSORS: These recommendations were developed at the request of the Canadian Blood Agency, which funds the provision of all coagulation-factor concentrates for people with congenital bleeding disorders, and were developed and endorsed by the AHCDC and the Medical and Scientific Advisory Committee of the Canadian Hemophilia Society. PMID:7600466

A new method to determine wound age in early vital skin injuries: a probability scoring system using expression levels of Fibronectin, CD62p and Factor VIII in wound hemorrhage.

PubMed

van de Goot, Franklin R W; Korkmaz, H Ibrahim; Fronczek, Judith; Witte, Birgit I; Visser, Rob; Ulrich, Magda M W; Begieneman, Mark P V; Rozendaal, Lawrence; Krijnen, Paul A J; Niessen, Hans W M

2014-11-01

In forensic autopsies it is important to determine the age of early vital skin wounds as accurate as possible. In addition to inflammation, coagulation is also induced in vital wounds. Analysis of blood coagulation markers in wound hemorrhage could therefore be an important additional discriminating factor in wound age determination. The aim of this study was to develop a wound age probability scoring system, based on the immunohistochemical expression levels of Fibronectin, CD62p and Factor VIII in wound hemorrhage. Tissue samples of (A) non injured control skin (n=383), and samples of mechanically induced skin injuries of known wound age, (B) injuries inflicted shortly before death (up to a few minutes old) (n=382), and (C) injuries inflicted 15-30 min before death (n=42) were obtained at autopsy in order to validate wound age estimation. Tissue slides were stained for Fibronectin, CD62p and Factor VIII and were subsequently scored for staining intensity (IHC score) in wound hemorrhage (1=minor, 2=moderate, 3=strong positive). Finally, probability scores of these markers were calculated. In at most 14% of the non-injured control samples, hemorrhage was found, with mean±standard deviation IHC scores of 0.1±0.4, 0.2±0.4 and 0.2±0.5 for Fibronectin, CD62p, and Factor VIII, respectively. Expression of these markers significantly increased to mean IHC scores 1.4±0.8 (Fibronectin), 1.2±0.6 (CD62p), and 1.6±0.8 (Factor VIII) in wounds inflicted shortly before death (few minutes old) and to 2.6±0.5 (Fibronectin), 2.5±0.6 (CD62p), and 2.8±0.4 (Factor VIII) in 15-30 min old wounds. The probabilities that a wound was non vital in case of an IH score 0 were 87%, 88% and 90% for Fibronectin, CD62p, and Factor VIII, respectively. In case of an IHC score 1 or 2, the probabilities that a wound was a few minutes old were 82/90%, 82/83% and 72/93%. Finally, in case of an IHC score 3, the probabilities that a wound was 15-30 min old were 65%, 76% and 55%. Based on the expression of Fibronectin, CD62p and Factor VIII in wound hemorrhage, we developed a probability scoring system that can be used in forensic autopsies to improve wound age estimation in early skin injuries. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Methods for detection of haemophilia carriers: a Memorandum*

PubMed Central

1977-01-01

This Memorandum discusses the problems and techniques involved in the detection of carriers of haemophilia A (blood coagulation factor VIII deficiency) and haemophilia B (factor IX deficiency), particularly with a view to its application to genetic counselling. Apart from the personal suffering caused by haemophilia, the proper treatment of haemophiliacs places a great strain on the blood transfusion services, and it is therefore important that potential carriers should have precise information about the consequences of their having children. The Memorandum classifies the types of carrier and describes the laboratory methods used for the assessment of coagulant activity and antigen concentration in blood. Particular emphasis is laid on the establishment of international, national, and laboratory (working) standards for factors VIII and IX and their calibration in international units (IU). This is followed by a detailed account of the statistical analysis of pedigree and laboratory data, which leads to an assessment of the likelihood that a particular person will transmit the haemophilia gene to her children. Finally, the problems and responsibilities involved in genetic counselling are considered. PMID:304395

Opposite effects of Agrimonia pilosa Ledeb aqueous extracts on blood coagulation function

PubMed Central

Yuan, Wufeng; Jiang, Lei; Wang, Huan

2017-01-01

Background Agrimonia pilosa Ledeb (APL) has showed anticoagulant and antithrombotic activities in some studies, whereas its actual effects on blood coagulation are still unclear. This study was designed to observe the in vitro effects of APL aqueous extracts on blood coagulation, as well as to investigate the underlying mechanisms. Methods Studies were divided into four groups: 0, 4, 20, and 80 g/L of APL aqueous extracts mixed with plasma or whole blood samples. Clotting time of whole blood, plasma coagulation tests, activities of plasma coagulation factors, plasma calcium ion, platelet aggregation test, and platelet fibrinogen receptor as well as the blood viscosity were measured. Results It was observed that the APL aqueous extracts in 4 g/L significantly prolonged the whole blood clotting time and activated partial thromboplastin time, shortened prothrombin time, decreased activities of coagulation factor VIII, IX and XI, and levels of platelet aggregation and fibrinogen receptor expression. However, coagulation factor VII activity, and blood viscosity were increased after the extracts treatment. And the effects of APL extracts were in a concentration-dependent manner (0–80 g/L). Conclusions The results suggest that APL aqueous extracts have a total anticoagulant activity, whereas they exhibit opposite effects of greater anticoagulant activity than pro-coagulant activity. PMID:28480193

Enzymatically oxidized phospholipids restore thrombin generation in coagulation factor deficiencies.

PubMed

Slatter, David A; Percy, Charles L; Allen-Redpath, Keith; Gajsiewicz, Joshua M; Brooks, Nick J; Clayton, Aled; Tyrrell, Victoria J; Rosas, Marcela; Lauder, Sarah N; Watson, Andrew; Dul, Maria; Garcia-Diaz, Yoel; Aldrovandi, Maceler; Heurich, Meike; Hall, Judith; Morrissey, James H; Lacroix-Desmazes, Sebastien; Delignat, Sandrine; Jenkins, P Vincent; Collins, Peter W; O'Donnell, Valerie B

2018-03-22

Hemostatic defects are treated using coagulation factors; however, clot formation also requires a procoagulant phospholipid (PL) surface. Here, we show that innate immune cell-derived enzymatically oxidized phospholipids (eoxPL) termed hydroxyeicosatetraenoic acid-phospholipids (HETE-PLs) restore hemostasis in human and murine conditions of pathological bleeding. HETE-PLs abolished blood loss in murine hemophilia A and enhanced coagulation in factor VIII- (FVIII-), FIX-, and FX-deficient human plasma . HETE-PLs were decreased in platelets from patients after cardiopulmonary bypass (CPB). To explore molecular mechanisms, the ability of eoxPL to stimulate individual isolated coagulation factor/cofactor complexes was tested in vitro. Extrinsic tenase (FVIIa/tissue factor [TF]), intrinsic tenase (FVIIIa/FIXa), and prothrombinase (FVa/FXa) all were enhanced by both HETE-PEs and HETE-PCs, suggesting a common mechanism involving the fatty acid moiety. In plasma, 9-, 15-, and 12-HETE-PLs were more effective than 5-, 11-, or 8-HETE-PLs, indicating positional isomer specificity. Coagulation was enhanced at lower lipid/factor ratios, consistent with a more concentrated area for protein binding. Surface plasmon resonance confirmed binding of FII and FX to HETE-PEs. HETE-PEs increased membrane curvature and thickness, but not surface charge or homogeneity, possibly suggesting increased accessibility to cations/factors. In summary, innate immune-derived eoxPL enhance calcium-dependent coagulation factor function, and their potential utility in bleeding disorders is proposed.

Enzymatically oxidized phospholipids restore thrombin generation in coagulation factor deficiencies

PubMed Central

Slatter, David A.; Percy, Charles L.; Allen-Redpath, Keith; Gajsiewicz, Joshua M.; Brooks, Nick J.; Tyrrell, Victoria J.; Lauder, Sarah N.; Watson, Andrew; Dul, Maria; Garcia-Diaz, Yoel; Aldrovandi, Maceler; Heurich, Meike; Hall, Judith; Lacroix-Desmazes, Sebastien; Delignat, Sandrine; Jenkins, P. Vincent; Collins, Peter W.; O’Donnell, Valerie B.

2018-01-01

Hemostatic defects are treated using coagulation factors; however, clot formation also requires a procoagulant phospholipid (PL) surface. Here, we show that innate immune cell–derived enzymatically oxidized phospholipids (eoxPL) termed hydroxyeicosatetraenoic acid–phospholipids (HETE-PLs) restore hemostasis in human and murine conditions of pathological bleeding. HETE-PLs abolished blood loss in murine hemophilia A and enhanced coagulation in factor VIII- (FVIII-), FIX-, and FX-deficient human plasma . HETE-PLs were decreased in platelets from patients after cardiopulmonary bypass (CPB). To explore molecular mechanisms, the ability of eoxPL to stimulate individual isolated coagulation factor/cofactor complexes was tested in vitro. Extrinsic tenase (FVIIa/tissue factor [TF]), intrinsic tenase (FVIIIa/FIXa), and prothrombinase (FVa/FXa) all were enhanced by both HETE-PEs and HETE-PCs, suggesting a common mechanism involving the fatty acid moiety. In plasma, 9-, 15-, and 12-HETE-PLs were more effective than 5-, 11-, or 8-HETE-PLs, indicating positional isomer specificity. Coagulation was enhanced at lower lipid/factor ratios, consistent with a more concentrated area for protein binding. Surface plasmon resonance confirmed binding of FII and FX to HETE-PEs. HETE-PEs increased membrane curvature and thickness, but not surface charge or homogeneity, possibly suggesting increased accessibility to cations/factors. In summary, innate immune-derived eoxPL enhance calcium-dependent coagulation factor function, and their potential utility in bleeding disorders is proposed. PMID:29563336

Autotransfusion from experimental hemothorax: levels of coagulation factors.

PubMed

Napoli, V M; Symbas, P J; Vroon, D H; Symbas, P N

1987-03-01

The coagulation system was investigated in five dogs undergoing autotransfusion from experimental hemothorax. One fourth of the blood volume was bled into the pleural space, drained, and autotransfused. The hemothorax blood showed: very prolonged PT and PTT; very low platelets and fibrinogen; midly elevated FDP; very low coagulation factors VIII, and V; reduced XII, prothrombin, X, XI, and VII. Partial clotting, mild fibrinolysis, and fibrin deposition over the pulmonary pleura seemed to cause incoagulability of hemothorax blood. Post autotransfusion arterial blood showed: normal PT and PTT; 25% decrease in platelets, and 31% decrease in fibrinogen from baseline values. There was also an overall 20% reduction of fibrinogen from baseline values. There was also an overall 20% reduction of all clotting factors, but their levels remained above 50% activity. It was concluded that autotransfusion from a hemothorax of 25% the blood volume in dogs causes a mild loss of hemostatic components, but does not significantly compromise the clotting mechanism.

Enhancement of the efficacy of therapeutic proteins by formulation with PEGylated liposomes; a case of FVIII, FVIIa and G-CSF.

PubMed

Yatuv, Rivka; Robinson, Micah; Dayan, Inbal; Baru, Moshe

2010-02-01

Improving the pharmacodynamics of protein drugs has the potential to improve the care and the quality of life of patients suffering from a variety of diseases. Four approaches to improve protein drugs are described: PEGylation, amino acid substitution, fusion to carrier proteins and encapsulation. A new platform technology based on the binding of proteins/peptides to the outer surface of PEGylated liposomes (PEGLip) is then presented. Binding of proteins to PEGLip is non-covalent, highly specific and dependent on an amino acid consensus sequence within the proteins. Association of proteins with PEGLip results in substantial enhancement of the pharmacodynamic properties of proteins following administration. This has been demonstrated in preclinical studies and clinical trials with coagulation factors VIII and VIIa. It has also been demonstrated in preclinical studies with granulocyte colony-stimulating factor. A mechanism is presented that explains the improvements in hemostatic efficacy of PEGLip-formulated coagulation factors VIII and VIIa. The reader will gain an understanding of the advantages and disadvantages of each of the approaches discussed. PEGLip formulation is an important new approach to improve the pharmacodynamics of protein drugs. This approach may be applied to further therapeutic proteins in the future.

A case control study on the structural equation model of the mechanism of coagulation and fibrinolysis imbalance in chronic schistosomiasis.

PubMed

Le, Aiping; Zhang, Lunli; Liu, Wei; Li, Xiaopeng; Ren, Jianwei; Ning, An

2017-02-01

A structural equation model was used for verification with chronic schistosomiasis to investigate the coagulation-anticoagulation system imbalance and to deduce the mechanism of D-dimer (D-D) level elevation in patients with advanced schistosome hepatic disease. We detected the plasma levels of tissue-type fiber plasminogen activator (tPA), urokinase type plasminogen activator (uPA), plasmin-antiplasmin complex (PAP), plasminogen (PLG), antithrombin (AT), plasminogen activator inhibitor 1 (PAI1), D-D, factor VIII: C (FVIII:C), antithrombin-III (AT-III), PLG, protein S (PS), and protein C (PC) in the healthy people as control (69), patients with chronic schistosomiasis (150) or advanced chronic schistosomiasis (90). FVIII, PAP, D-D, tPA, and uPA plasma levels were significantly higher in the chronic group than in the control group and were also significantly higher in the advanced group. However, AT-III, PC, PS, AT, PLG, and PAI1 plasma levels in the advanced and chronic groups were significantly lower than those in the control group. With progression of disease in patients with schistosomiasis japonica, a hypercoagulable state is induced by the coagulation-anticoagulation imbalance, eventually leading to patients with high levels of D-D. Furthermore, we established a structural equation model path of a "chronic schistosomiasis disease stage-(coagulation-anticoagulation-fibrinolysis)-D-D." By using analysis of moment structures (AMOS), it was shown that the chronic schistosomiasis stage was positively related to factor VIII and had negative correlation with AT-III; a good positive correlation with PAP, tPA, and uPA; and a good negative correlation with PLG and PAI1. In addition, our results show that the path coefficient of anticoagulation-fibrinolysis system to the chronic stage of schistosomiasis or D-D levels was significantly higher than that of the coagulation system. In conclusion, the coagulation and fibrinolysis imbalance in patients with chronic schistosomiasis, especially with advanced schistosomiasis, is due to the progression of disease stages.

Effect of platelet-derived β-thromboglobulins on coagulation.

PubMed

Egan, Karl; van Geffen, Johanna P; Ma, Hui; Kevane, Barry; Lennon, Aine; Allen, Seamus; Neary, Elaine; Parsons, Martin; Maguire, Patricia; Wynne, Kieran; O' Kennedy, Richard; Heemskerk, Johan W M; Áinle, Fionnuala Ní

2017-06-01

β-thromboglobulins are derived from the cleavage of the CXC chemokine platelet basic protein and are released in high concentrations by activated platelets. Platelet-derived β-thromboglobulins (βTG) share 70% homology with platelet factor 4 (PF4), another CXC chemokine released by activated platelets. PF4 modulates coagulation by inhibiting heparin-antithrombin interactions, promoting protein C activation, and attenuating the activity of activated protein C. In contrast, the effect of βTG on coagulation is unknown. Clotting times, thrombin generation, chromogenic clotting factor assays, and surface plasmon resonance (SPR) were used to assess the effect of purified βTG on coagulation. In normal pooled plasma, βTG shortened the lagtime and time to peak thrombin generation of tissue factor (TF)-dependent and TF-independent thrombin generation. In factor VIII and factor IX-deficient plasmas, βTG induced thrombin generation in the absence of a TF stimulus and in the presence of anti-TF and factor VIIa inhibitory antibodies. The procoagulant effect was not observed when thrombin generation was independent of factor X activation (supplementation of factor X-deficient plasma with factor Xa). Cleavage of a factor Xa-specific chromogenic substrate was observed when βTG was incubated with factor X, suggesting a direct interaction between βTG and factor X. Using SPR, βTG were found to bind to immobilised factor X in a dose dependent manner. βTG modulate coagulation in vitro via an interaction with factor X. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anxiety and depression in patients three months after myocardial infarction: Association with markers of coagulation and the relevance of age.

PubMed

Geiser, Franziska; Urbach, Anne Sarah; Harbrecht, Ursula; Conrad, Rupert; Pötzsch, Bernd; Amann, Nele; Kiesewetter, Katharina; Sieke, Alexandra; Wolffs, Kyra; Skowasch, Dirk

2017-08-01

Anxiety and depression are associated with an activation of coagulation and an impairment of fibrinolysis, which may contribute to the increased cardiovascular risk associated with the two disorders. However, very few studies have examined the impact of psychological distress on coagulation factors in coronary artery disease patients. The aim of this study was to assess the correlation between anxiety/depression and factors of coagulation and fibrinolysis in patients who had suffered an acute MI three months prior. In 148 patients, anxiety and depression were assessed by the Hospital Anxiety and Depression Scale (HADS) shortly after MI and three months later. At the second time of assessment, plasma levels of fibrinogen, factor VII, factor VIII, von Willebrand factor, prothrombin-fragment 1 and 2, tissue-plasminogen-activator, plasminogen activator inhibitor-1, D-dimer, and homocysteine were measured. In 32% of the patients, elevated levels of anxiety and depression were found three months after a MI. Multiple regression analyses showed that coagulation and fibrinolysis markers were not significantly associated with HADS anxiety and depression scores. We found that age, gender, BMI, and smoking status were significant predictors for haemostasis factors. A higher age was associated with a higher coagulability but lower anxiety levels. We measured parameters of coagulation and fibrinolysis in patients three months after MI and found no predictive value of HADS anxiety and depression scores shortly after MI or at the time of blood sampling. The effects of age on the relationship between anxiety and haemostasis should be further investigated. Copyright © 2017 Elsevier Inc. All rights reserved.

Differentiation of embryonic stem cells into hepatocytes that coexpress coagulation factors VIII and IX.

PubMed

Cao, Jun; Shang, Chang-zhen; Lü, Li-hong; Qiu, De-chuan; Ren, Meng; Chen, Ya-jin; Min, Jun

2010-11-01

To establish an efficient culture system to support embryonic stem (ES) cell differentiation into hepatocytes that coexpress F-VIII and F-IX. Mouse E14 ES cells were cultured in differentiation medium containing sodium butyrate (SB), basic fibroblast growth factor (bFGF), and/or bone morphogenetic protein 4 (BMP4) to induce the differentiation of endoderm cells and hepatic progenitor cells. Hepatocyte growth factor, oncostatin M, and dexamethasone were then used to induce the maturation of ES cell-derived hepatocytes. The mRNA expression levels of endoderm-specific genes and hepatocyte-specific genes, including the levels of F-VIII and F-IX, were detected by RT-PCR and real-time PCR during various stages of differentiation. Protein expression was examined by immunofluorescence and Western blot. At the final stage of differentiation, flow cytometry was performed to determine the percentage of cells coexpressing F-VIII and F-IX, and ELISA was used to detect the levels of F-VIII and F-IX protein secreted into the culture medium. The expression of endoderm-specific and hepatocyte-specific markers was upregulated to highest level in response to the combination of SB, bFGF, and BMP4. Treatment with the three inducers during hepatic progenitor differentiation significantly enhanced the mRNA and protein levels of F-VIII and F-IX in ES cell-derived hepatocytes. More importantly, F-VIII and F-IX were coexpressed with high efficiency at the final stage of differentiation, and they were also secreted into the culture medium. We have established a novel in vitro differentiation protocol for ES-derived hepatocytes that coexpress F-VIII and F-IX that may provide a foundation for stem cell replacement therapy for hemophilia.

Virus elimination during the recycling of chromatographic columns used during the manufacture of coagulation factors.

PubMed

Roberts, Peter L

2014-07-01

Various chromatographic procedures are used during the purification and manufacture of plasma products such as coagulation factors. These steps contribute to the overall safety of such products by removing potential virus contamination. Virus removal by two affinity chromatography procedures, i.e. monoclonal antibody chromatography and metal chelate chromatography (immobilised metal ion affinity chromatography), used during the manufacture of the high purity factor VIII (Replenate®) and factor IX (Replenine®-VF), respectively, has been investigated. In addition, as these columns are recycled after use, the effectiveness of the sanitisation procedures for preventing possible cross-contamination, has also been investigated. Both chromatographic steps proved effective for eliminating a range of model enveloped and non-enveloped viruses by 4 to >6 and 5 to >8 log for the monoclonal and metal chelate columns, respectively. The effectiveness of the relatively mild column sanitisation conditions used, i.e. ethanol for factor IX and acetic acid for factor VIII, was confirmed using non-spiked column runs. The chemicals used contributed to virus elimination by inactivation and/or by physical removal of the virus. In summary, these studies demonstrate that potential virus contamination between chromatographic runs can be prevented when an effective column recycling and sanitisation procedure is included. Copyright © 2014 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Acidosis and Correction of Acidosis Does Not Affect rFVIIa Function in Swine

DTIC Science & Technology

2012-12-15

and its correction (or normalization of pH) has been suggested before clinical use of rFVIIa [21, 22]. FVII is one of the many coagulation factors ...A or B (deficient in Factor VIII and Factor IX). Mice lacking FVII die in-utero or soon after birth due to vascular and hemostatic defects [23...the activity of recombinant activated Factor VII (rFVIIa) in vitro. However, it is not known if acidosis induced by hemorrhagic shock or infusion of

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.

Cerebral venous thrombosis associated with thyrotoxicosis, the use of desmopressin and elevated factor VIII/von Willebrand factor.

PubMed

Waheed, Waqar; Aljerdi, Salman; Decker, Barbara; Cushman, Mary; Hamill, Robert W

2016-08-08

Cerebral venous thrombosis (CVT) is an uncommon disorder associated with diverse processes. We report a patient who, while receiving desmopressin and contraceptive pills (OCP), developed straight sinus thrombosis. Clinical assessment and laboratory investigations revealed untreated hyperthyroidism and a hypercoagulable state, characterised by high levels of von Willebrand factor, factor VIII coagulant activity and IgM cardiolipin antibody. The clinical picture improved with anticoagulation, treatment of hyperthyroidism and discontinuation of OCP and desmopressin. To the best of our knowledge, the association between the use of oral desmopressin and CVT has not been described. The multiple risk factors present in our case were probably additive in increasing the risk of CVT. Although this case represents a rare occurrence, practitioners should be alerted to the possible associations of desmopressin, oral contraceptives and Graves' disease with venous thrombosis. 2016 BMJ Publishing Group Ltd.

Elevated plasma factor VIII enhances venous thrombus formation in rabbits: contribution of factor XI, von Willebrand factor and tissue factor.

PubMed

Sugita, Chihiro; Yamashita, Atsushi; Matsuura, Yunosuke; Iwakiri, Takashi; Okuyama, Nozomi; Matsuda, Shuntaro; Matsumoto, Tomoko; Inoue, Osamu; Harada, Aya; Kitazawa, Takehisa; Hattori, Kunihiro; Shima, Midori; Asada, Yujiro

2013-07-01

Elevated plasma levels of factor VIII (FVIII) are associated with increased risk of deep venous thrombosis. The aim of this study is to elucidate how elevated FVIII levels affect venous thrombus formation and propagation in vivo. We examined rabbit plasma FVIII activity, plasma thrombin generation, whole blood coagulation, platelet aggregation and venous wall thrombogenicity before and one hour after an intravenous infusion of recombinant human FVIII (rFVIII). Venous thrombus induced by the endothelial denudation of rabbit jugular veins was histologically assessed. Thrombus propagation was evaluated as indocyanine green fluorescence intensity. Argatroban, a thrombin inhibitor, and neutralised antibodies for tissue factor (TF), factor XI (FXI), and von Willebrand factor (VWF) were infused before or after thrombus induction to investigate their effects on venous thrombus formation or propagation. Recombinant FVIII (100 IU/kg) increased rabbit plasma FVIII activity two-fold and significantly enhanced whole blood coagulation and total plasma thrombin generation, but did not affect initial thrombin generation time, platelet aggregation and venous wall thrombogenicity. The rFVIII infusion also increased the size of venous thrombus 1 hour after thrombus induction. Argatroban and the antibodies for TF, FXI or VWF inhibited such enhanced thrombus formation and all except TF suppressed thrombus propagation. In conclusion, elevated plasma FVIII levels enhance venous thrombus formation and propagation. Excess thrombin generation by FXI and VWF-mediated FVIII recruitment appear to contribute to the growth of FVIII-driven venous thrombus.

Innovative Approaches for Immune Tolerance to Factor VIII in the Treatment of Hemophilia A

PubMed Central

Sherman, Alexandra; Biswas, Moanaro; Herzog, Roland W.

2017-01-01

Hemophilia A (coagulation factor VIII deficiency) is a debilitating genetic disorder that is primarily treated with intravenous replacement therapy. Despite a variety of factor VIII protein formulations available, the risk of developing anti-dug antibodies (“inhibitors”) remains. Overall, 20–30% of patients with severe disease develop inhibitors. Current clinical immune tolerance induction protocols to eliminate inhibitors are not effective in all patients, and there are no prophylactic protocols to prevent the immune response. New experimental therapies, such as gene and cell therapies, show promising results in pre-clinical studies in animal models of hemophilia. Examples include hepatic gene transfer with viral vectors, genetically engineered regulatory T cells (Treg), in vivo Treg induction using immune modulatory drugs, and maternal antigen transfer. Furthermore, an oral tolerance protocol is being developed based on transgenic lettuce plants, which suppressed inhibitor formation in hemophilic mice and dogs. Hopefully, some of these innovative approaches will reduce the risk of and/or more effectively eliminate inhibitor formation in future treatment of hemophilia A. PMID:29225598

Factor VIII Interacts with the Endocytic Receptor Low-density Lipoprotein Receptor-related Protein 1 via an Extended Surface Comprising "Hot-Spot" Lysine Residues.

PubMed

van den Biggelaar, Maartje; Madsen, Jesper J; Faber, Johan H; Zuurveld, Marleen G; van der Zwaan, Carmen; Olsen, Ole H; Stennicke, Henning R; Mertens, Koen; Meijer, Alexander B

2015-07-03

Lysine residues are implicated in driving the ligand binding to the LDL receptor family. However, it has remained unclear how specificity is regulated. Using coagulation factor VIII as a model ligand, we now study the contribution of individual lysine residues in the interaction with the largest member of the LDL receptor family, low-density lipoprotein receptor-related protein (LRP1). Using hydrogen-deuterium exchange mass spectrometry (HDX-MS) and SPR interaction analysis on a library of lysine replacement variants as two independent approaches, we demonstrate that the interaction between factor VIII (FVIII) and LRP1 occurs over an extended surface containing multiple lysine residues. None of the individual lysine residues account completely for LRP1 binding, suggesting an additive binding model. Together with structural docking studies, our data suggest that FVIII interacts with LRP1 via an extended surface of multiple lysine residues that starts at the bottom of the C1 domain and winds around the FVIII molecule. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

[Endothelial microparticles (EMP) in physiology and pathology].

PubMed

Sierko, Ewa; Sokół, Monika; Wojtukiewicz, Marek Z

2015-08-18

Endothelial microparticles (EMP) are released from endothelial cells (ECs) in the process of activation and/or apoptosis. They harbor adhesive molecules, enzymes, receptors and cytoplasmic structures and express a wide range of various constitutive antigens, typical for ECs, at their surface. Under physiological conditions the concentration of EMP in the blood is clinically insignificant. However, it was reported that under pathological conditions EMP concentration in the blood might slightly increase and contribute to blood coagulation, angiogenesis and inflammation. It has been shown that EMP directly and indirectly contribute to the activation of blood coagulation. Endothelial microparticles directly participate in blood coagulation through their surface tissue factor (TF) - a major initiator of blood coagulation. Furthermore, EMP exhibit procoagulant potential via expression of negatively charged phospholipids at their surface, which may promote assembly of coagulation enzymes (TF/VII, tenases and prothrombinase complexes), leading to thrombus formation. In addition, they provide a binding surface for coagulation factors: IXa, VIII, Va and IIa. Moreover, it is possible that EMP transfer TF from TF-bearing EMP to activated platelets and monocytes by binding them through adhesion molecules. Also, EMP express von Willebrand factor, which may facilitate platelet aggregation. Apart from their procoagulant properties, it was demonstrated that EMP may express adhesive molecules and metalloproteinases (MMP-2, MMP-9) at their surface and release growth factors, which may contribute to angiogenesis. Additionally, surface presence of C3 and C4 - components of the classical pathway - suggests pro-inflammatory properties of these structures. This article contains a summary of available data on the biology and pathophysiology of endothelial microparticles and their potential role in blood coagulation, angiogenesis and inflammation.

Hemostasis in Overt and Subclinical Hyperthyroidism

PubMed Central

Ordookhani, Arash; Burman, Kenneth D.

2017-01-01

Context There are contradictory results on the effect of hyperthyroidism on hemostasis. Inadequate population-based studies limited their clinical implications, mainly on the risk of venous thromboembolism (VTE). The present review focuses on hemostatic changes in overt and subclinical hyperthyroidism. Methods A systematic literature search was conducted employing MEDLINE database. The following words were used for the search: Hyperthyroidism; thyrotoxicosis; Graves disease; goiter, nodular; hemostasis; blood coagulation factors; blood coagulation disorders; venous thromboembolism; bleeding; fibrinolysis. The articles that were related to hyperthyroidism and hemostasis are used in this manuscript. Results Hyperthyroidism, either overt or subclinical, renders a hypercoagulable state, although there are several studies with contradictory findings in the literature. Hypercoagulability may be caused by an increase in the level of various coagulation factors such as factor (F) VIII, FX, FIX, von Willebrand F (vWF), and fibrinogen, while hypofibrinolysis by changes in coagulation parameters such as a decrease in plasmin and plasmin activator or an increase in α2-antiplasmin, plasminogen activator inhibitor-1 and thrombin activatable fibrinolysis inhibitor Conclusions Although many reports are in favor of a hypercoagulable state in overt hyperthyroidism but this finding at the biochemical level and its clinical implication, on the occurrence of VTE, has yet to be confirmed. PMID:29201071

A global quantitative survey of hemostatic assessment in postpartum hemorrhage and experience with associated bleeding disorders.

PubMed

James, Andra H; Cooper, David L; Paidas, Michael J

2017-01-01

Coagulopathy may be a serious complicating or contributing factor to postpartum hemorrhage (PPH), and should be promptly recognized to ensure proper bleeding management. This study aims to evaluate the approaches of obstetrician-gynecologists worldwide towards assessing massive PPH caused by underlying bleeding disorders. A quantitative survey was completed by 302 obstetrician-gynecologists from 6 countries (the UK, France, Germany, Italy, Spain, and Japan). The survey included questions on the use of hematologic laboratory studies, interpretation of results, laboratory's role in coagulation assessments, and experience with bleeding disorders. Overall, the most common definitions of "massive" PPH were >2,000 mL (39%) and >1,500 mL (34%) blood loss. The most common criteria for rechecking a "stat" complete blood count and for performing coagulation studies were a drop in blood pressure (73%) and ongoing visible bleeding (78%), respectively. Laboratory coagulation (prothrombin time/activated partial thromboplastin time [PT/aPTT]) and factor VIII/IX assays were performed on-site more often than were mixing studies (laboratory coagulation studies, 93%; factor VIII/IX assays, 63%; mixing studies, 22%). Most commonly consulted sources of additional information were colleagues within one's own specialty (68%) and other specialists (67%). Most respondents had consulted with a hematologist (78%; least, Germany [56%]; greatest, UK [98%]). The most common reason for not consulting was hematologist unavailability (44%). The most commonly reported thresholds for concern with PT and aPTT were 13 to 20 seconds (36%) and 30 to 45 seconds (50%), respectively. Most respondents reported having discovered an underlying bleeding disorder (58%; least, Japan [35%]; greatest, Spain [74%]). Global survey results highlight similarities and differences between countries in how PPH is assessed and varying levels of obstetrician-gynecologist experience with identification of underlying bleeding disorders and engagement of hematology consultants. Opportunities to improve patient management of PPH associated with bleeding disorders include greater familiarity with interpreting PT/aPTT test results and identification of and consistent consultation with hematologists with relevant expertise.

A hypothesis: factor VII governs clot formation, tissue repair and apoptosis.

PubMed

Coleman, Lewis S

2007-01-01

A hypothesis: thrombin is a "Universal Enzyme of Energy Transduction" that employs ATP energy in flowing blood to activate biochemical reactions and cell effects in both hemostasis and tissue repair. All cells possess PAR-1 (thrombin) receptors and are affected by thrombin elevations, and thrombin effects on individual cell types are determined by their unique complement of PAR-1 receptors. Disruption of the vascular endothelium (VE) activates a tissue repair mechanism (TRM) consisting of the VE, tissue factor (TF), and circulating Factors VII, IX and X that governs localized thrombin elevations to activate clot formation and cellular effects that repair tissue damage. The culmination of the repair process occurs with the restoration of the VE followed by declines in thrombin production that causes Apoptosis ("programmed cell death") in wound-healing fibroblasts, which functions as a mechanism to draw wound edges together. The location and magnitude of TRM activity governs the location and magnitude of Factor VIII activity and clot formation, but the large size of Factor VIII prevents it from penetrating the clot formed by its activity, so that its effects are self-limiting. Factors VII, IX and X function primarily as tissue repair enzymes, while Factor VIII and Factor XIII are the only serine protease enzymes in the "Coagulation Cascade" that are exclusively associated with hemostasis.

A Protocol for the Preparation of Cryoprecipitate and Cryo-depleted Plasma for Proteomic Studies.

PubMed

Sparrow, Rosemary L; Simpson, Richard J; Greening, David W

2017-01-01

Cryoprecipitate is a concentrate of high-molecular-weight plasma proteins that precipitate when frozen plasma is slowly thawed at 1-6 °C. The concentrate contains factor VIII (antihemophilic factor), von Willebrand factor (vWF), fibrinogen, factor XIII, fibronectin, and small amounts of other plasma proteins. Clinical grade preparations of cryoprecipitate are mainly used to treat fibrinogen deficiency caused by acute bleeding or functional abnormalities of the fibrinogen protein. In the past, cryoprecipitate was used to treat von Willebrand disease and hemophilia A (factor VIII deficiency), but the availability of more highly purified coagulation factor concentrates or recombinant protein preparations has superseded the use of cryoprecipitate for these coagulopathies. Cryo-depleted plasma ("cryosupernatant") is the plasma supernatant remaining following removal of the cryoprecipitate from frozen-thawed plasma. It contains all the other plasma proteins and clotting factors present in plasma that remain soluble during cold-temperature thawing of the plasma. This protocol describes the clinical-scale preparation of cryoprecipitate and cryo-depleted plasma for proteomic studies.

Crystal Structure of the Bovine lactadherin C2 Domain, a Membrane Binding Motif, Shows Similarity to the C2 Domains of Factor V and Factor VIII

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

Lin,L.

2007-01-01

Lactadherin, a glycoprotein secreted by a variety of cell types, contains two EGF domains and two C domains with sequence homology to the C domains of blood coagulation proteins factor V and factor VIII. Like these proteins, lactadherin binds to phosphatidylserine (PS)-containing membranes with high affinity. We determined the crystal structure of the bovine lactadherin C2 domain (residues 1 to 158) at 2.4 {angstrom}. The lactadherin C2 structure is similar to the C2 domains of factors V and VIII (rmsd of C{sub {alpha}} atoms of 0.9 {angstrom} and 1.2 {angstrom}, and sequence identities of 43% and 38%, respectively). The lactadherinmore » C2 domain has a discoidin-like fold containing two {beta}-sheets of five and three antiparallel {beta}-strands packed against one another. The N and C termini are linked by a disulfide bridge between Cys1 and Cys158. One {beta}-turn and two loops containing solvent-exposed hydrophobic residues extend from the C2 domain {beta}-sandwich core. In analogy with the C2 domains of factors V and VIII, some or all of these solvent-exposed hydrophobic residues, Trp26, Leu28, Phe31, and Phe81, likely participate in membrane binding. The C2 domain of lactadherin may serve as a marker of cell surface phosphatidylserine exposure and may have potential as a unique anti-thrombotic agent.« less

Crystal Structure of the Bovine lactadherin C2 Domain, a Membrane Binding Motif, Shows Similarity of the C2 Domains of Factor V and Factor VIII

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

Lin,L.; Huai, Q.; Huang, M.

2007-01-01

Lactadherin, a glycoprotein secreted by a variety of cell types, contains two EGF domains and two C domains with sequence homology to the C domains of blood coagulation proteins factor V and factor VIII. Like these proteins, lactadherin binds to phosphatidylserine (PS)-containing membranes with high affinity. We determined the crystal structure of the bovine lactadherin C2 domain (residues 1 to 158) at 2.4 Angstroms. The lactadherin C2 structure is similar to the C2 domains of factors V and VIII (rmsd of C? atoms of 0.9 Angstroms and 1.2 Angstroms, and sequence identities of 43% and 38%, respectively). The lactadherin C2more » domain has a discoidin-like fold containing two ?-sheets of five and three antiparallel ?-strands packed against one another. The N and C termini are linked by a disulfide bridge between Cys1 and Cys158. One ?-turn and two loops containing solvent-exposed hydrophobic residues extend from the C2 domain ?-sandwich core. In analogy with the C2 domains of factors V and VIII, some or all of these solvent-exposed hydrophobic residues, Trp26, Leu28, Phe31, and Phe81, likely participate in membrane binding. The C2 domain of lactadherin may serve as a marker of cell surface phosphatidylserine exposure and may have potential as a unique anti-thrombotic agent.« less

Myelofibrosis and acquired hemophilia A: a case report.

PubMed

Wrobel, Marie; Comio, Emilie; Gay, Valerie; Baroudi, Noureddine; Meyer, Pascal; Chuniaud-Louche, Christine; Hacini, Maya; Pica, Gian Matteo

2016-05-07

Myelofibrosis and acquired hemophilia A is a rare association. To the best of our knowledge only one case of myelofibrosis and acquired hemophilia A has been previously described. A 66-year-old Caucasian man diagnosed with myelofibrosis evolving in acute myeloid leukemia was referred to us for postoperative bleeding. Hemostatic studies showed prolonged activated partial thromboplastin time, decreased factor VIII coagulation, and a high factor VIII inhibitor titer; these findings led to a diagnosis of acquired hemophilia A for which he was treated with methylprednisolone and recombinant activated factor VII on admission. Due to a lack of response he was subsequently treated with rituximab combined with activated prothrombin complex concentrates. Furthermore, he received azacytidine to treat the underlying hematological malignancies. Immunosuppressive rituximab therapy resolved acquired hemophilia A with marked efficacy. Rapid and accurate diagnosis, effective hemostatic therapy, and timely treatment for underlying disease are important in the management of acquired hemophilia A secondary to hematological malignancy.

Protein A sepharose immunoadsorption: immunological and haemostatic effects in two cases of acquired haemophilia.

PubMed

Guillet, B; Kriaa, F; Huysse, M G; Proulle, V; George, C; Tchernia, G; D'Oiron, R; Laurian, Y; Charpentier, B; Lambert, T; Dreyfus, M

2001-09-01

Acquired haemophilia is a life-threatening disorder caused by circulating auto-antibodies that inhibit factor VIII coagulant activity (FBIII:C). Immunoadsorption on protein A sepharose (IA-PA) was performed in two bleeding patients with acquired haemophilia: we observed a dramatic and quick decrease in the anti-FVIII:C inhibitor titre leading to a normal, albeit transient, haemostatic status. In one case, IA-PA was the only procedure which succeeded in stopping massive haemorrhage. In the second case, IA-PA reinforced the haemostatic effect of recombinant activated factor VII by increasing the endogenous plasma factor VIII level. The efficacy of IA-PA was sustained with immunosuppressive treatment introduced, respectively, 10 and 15 d before the IA-PA procedures. Our experience with IA-PA suggests that this extracorporeal anti-FVIII:C removal procedure is a valuable therapeutic tool for acquired haemophilia and can alleviate life-threatening haemorrhages.

Clinical and Laboratory Approaches to Hemophilia A

PubMed Central

Mansouritorghabeh, Hassan

2015-01-01

Hemophilia A is a worldwide disorder of coagulation system. It is a male disorder, yet females with hemophilia are rarely seen in communities with high rate of consanguineous marriages. The abnormalities in factor VIII gene transfer as an X-linked pattern in the family, affects as many as one-third of patients who had no family history of abnormality and thus the occurrence of a sporadic mutation could be documented. Hemorrhagic symptoms usually correlate with the plasma level of factor VIII and comprise a wide range of hemorrhagic pictures, including from fatal spontaneous bleeding in the brain to ecchymosis of the skin. The coagulation study needs to differentiate between the two types of hemophilia A and B as well as the categorization of the disease severity. In the developing countries, due to limitations in diagnostic hemostasis facilities and a scant number of experts in the field, it is estimated that noticeable numbers of undiagnosed patients with hemophilia A exist. Occasionally, we encounter undiagnosed cases by general physicians while having hemorrhagic symptoms. The purpose of this review is to recap clinical and diagnostic parameters, pitfalls, and interpretation of coagulation assay in hemophilia A. A literature review was done in PubMed and Scopus medical search engines using the keywords “Hemophilia” and “Haemophilia”. A time limitation for the publication beyond 1995 and publication in the English language were considered. A total of 94 original articles and chapters of books was selected for the current review. Additionally, a comprehensive and up-to-date information on the clinical and laboratory features for the diagnosis of hemophilia is also presented. PMID:25999618

Influence of class I and II HLA alleles on inhibitor development in severe haemophilia A patients from the south of Brazil.

PubMed

De Barros, M F; Herrero, J C M; Sell, A M; De Melo, F C; Braga, M A; Pelissari, C B; Machado, J; De Souza Schiller, S; De Souza Hirle, L; Visentainer, J E L

2012-05-01

Congenital haemophilia A is a chromosome-linked recessive disorder caused by the deficiency or reduction of factor VIII (FVIII) pro-coagulant activity. During treatment, some patients develop alloantibodies (FVIII inhibitors) that neutralize the action of exogenously administered FVIII. Currently, the presence of these inhibitors is the most serious adverse event found in replacement therapy. Some studies have suggested that genetic factors influence the development of the FVIII coagulation inhibitors. To identify the class I and II alleles that may be influencing the formation of inhibitors in severe haemophilic patients. Genotyping of the class I (HLA-A, -B and -C) and class II (HLA-DRB1, -DQA1 and -DQB1) alleles of 122 patients with severe haemophilia A, including 36 who had developed antibodies to factor VIII, was performed. After the comparison of the group without inhibitors and the group with inhibitors, HLA-C*16 [Odds ratio (OR) = 7.73; P = 0.0092] and HLA-DRB1*14 (OR = 4.52; P = 0.0174) were found to be positively associated with the formation of the inhibitors. These results confirm that HLA alleles are involved in inhibitor production and could be used as a tool for recognition of groups at high risk of possible inhibitor development in Southern Brazilian haemophilic patients. © 2011 Blackwell Publishing Ltd.

Venom Protein C activators as diagnostic agents for defects of protein C System.

PubMed

Ramzan, Faiqah; Asmat, Andleeb

2018-06-18

Background Protein C is a vitamin K dependent plasma zymogen. It prevents clotting by inhibiting clotting by inactivating factor V and factor VIII. Protein C activation pathway involves three steps: (i) Activation of protein C; (ii) Inhibition of coagulation through inactivating factor V and VIII by activated protein C and (iii) Inhibition of activated protein C by plasma protease inhibitors specific for this enzyme. Proteinases converts the zymogen Protein C (PC) of vertebrates into activated PC, which has been detected in several snake venoms. Most PC activators have been purified from venom of snake species belonging to the genera of the Agkistrodon complex. Unlike the physiological thrombin-catalyzed PC activation reaction which requires thrombomodulin as a cofactor, most snake venom activators directly convert the zymogen PC into the catalytically active form which can easily be determined by means of coagulation or chromogenic substrate techniques. Conclusion The fast-acting PC activator Protac® from Agkistrodon contortrix (southern copperhead snake) venom has been found to have broad application in diagnostic practice for the determination of disorders in the PC pathway. Recently, screening assays for the PC pathway have been introduced, based on the observation that the PC pathway is probably the most important physiological barrier against thrombosis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Quality control in the development of coagulation factor concentrates.

PubMed

Snape, T J

1987-01-01

Limitation of process change is a major factor contributing to assurance of quality in pharmaceutical manufacturing. This is particularly true in the manufacture of coagulation factor concentrates, for which presumptive testing for poorly defined product characteristics is an integral feature of finished product quality control. The development of new or modified preparations requires that this comfortable position be abandoned, and that the effect on finished product characteristics of changes to individual process steps (and components) be assessed. The degree of confidence in the safety and efficacy of the new product will be determined by, amongst other things, the complexity of the process alteration and the extent to which the results of finished product tests can be considered predictive. The introduction of a heat-treatment step for inactivation of potential viral contaminants in coagulation factor concentrates presents a significant challenge in both respects, quite independent of any consideration of assessment of the effectiveness of the viral inactivation step. These interactions are illustrated by some of the problems encountered with terminal dry heat-treatment (72 h. at 80 degrees C) of factor VIII and prothrombin complex concentrates manufactured by the Blood Products Laboratory.

Development, Validation, and Application of a Novel Ligand-Binding Assay to Selectively Measure PEGylated Recombinant Human Coagulation Factor VIII (BAX 855).

PubMed

Weber, Alfred; Engelmaier, Andrea; Hainzelmayer, Sandra; Minibeck, Eva; Anderle, Heinz; Schwarz, Hans Peter; Turecek, Peter L

2015-10-21

BAX 855 is a PEGylated recombinant factor VIII preparation that showed prolonged circulatory half-life in nonclinical and clinical studies. This paper describes the development, validation, and application of a novel ligand-binding assay (LBA) to selectively measure BAX 855 in plasma. The LBA is based on PEG-specific capture of BAX 855, followed by immunological factor VIII (FVIII)-specific detection of the antibody-bound BAX 855. This assay principle enabled sensitive measurement of BAX 855 down to the low nanomolar range without interference from non-PEGylated FVIII as demonstrated by validation data for plasma from animals typically used for nonclinical characterization of FVIII. The selectivity of an in-house-developed anti-PEG and a commercially available preparation, shown by competition studies to primarily target the terminating methoxy group of PEG, also allowed assessment of the intactness of the attached PEG chains. Altogether, this new LBA adds to the group of methods to selectively, accurately, and precisely measure a PEGylated drug in complex biological matrices. The feasibility and convenience of using this method was demonstrated during extensive nonclinical characterization of BAX 855.

Nattokinase decreases plasma levels of fibrinogen, factor VII, and factor VIII in human subjects.

PubMed

Hsia, Chien-Hsun; Shen, Ming-Ching; Lin, Jen-Shiou; Wen, Yao-Ke; Hwang, Kai-Lin; Cham, Thau-Ming; Yang, Nae-Cherng

2009-03-01

Nattokinase, a serine proteinase from Bacillus subtilis, is considered to be one of the most active functional ingredients found in natto. In this study, we hypothesized that nattokinase could reduce certain factors of blood clotting and lipids that are associated with an increase risk for cardiovascular disease (CVD). Thus, an open-label, self-controlled clinical trial was conducted on subjects of the following groups: healthy volunteers (Healthy Group), patients with cardiovascular risk factors (Cardiovascular Group), and patients undergoing dialysis (Dialysis Group). All subjects ingested 2 capsules of nattokinase (2000 fibrinolysis units per capsule) daily orally for 2 months. The laboratory measurements were performed on the screening visit and, subsequently, regularly after the initiation of the study. The intent-to-treat analysis was performed on all 45 enrolled subjects. By use of mixed model analysis, a significant time effect, but not group effect, was observed in the change from baseline of fibrinogen (P = .003), factor VII (P < .001), and factor VIII (P < .001), suggesting that the plasma levels of the 3 coagulation factors continuously declined during intake; also, the extents of decrease were similar between groups. After 2 months of administration, fibrinogen, factor VII, and factor VIII decreased 9%, 14%, and 17%, respectively, for the Healthy Group; 7%, 13%, and 19%, respectively, for the Cardiovascular Group; and 10%, 7%, and 19%, respectively, for the Dialysis Group, whereas blood lipids were unaffected by nattokinase. No significant changes of uric acid or notable adverse events were observed in any of the subjects. In summary, this study showed that oral administration of nattokinase could be considered as a CVD nutraceutical by decreasing plasma levels of fibrinogen, factor VII, and factor VIII.

Venom Concentrations and Clotting Factor Levels in a Prospective Cohort of Russell's Viper Bites with Coagulopathy.

PubMed

Isbister, Geoffrey K; Maduwage, Kalana; Scorgie, Fiona E; Shahmy, Seyed; Mohamed, Fahim; Abeysinghe, Chandana; Karunathilake, Harendra; O'Leary, Margaret A; Gnanathasan, Christeine A; Lincz, Lisa F

2015-01-01

Russell's viper envenoming is a major problem in South Asia and causes venom induced consumption coagulopathy. This study aimed to investigate the kinetics and dynamics of venom and clotting function in Russell's viper envenoming. In a prospective cohort of 146 patients with Russell's viper envenoming, we measured venom concentrations, international normalised ratio [INR], prothrombin time (PT), activated partial thromboplastin time (aPTT), coagulation factors I, II, V, VII, VIII, IX and X, and von Willebrand factor antigen. The median age was 39 y (16-82 y) and 111 were male. The median peak INR was 6.8 (interquartile range [IQR]: 3.7 to >13), associated with low fibrinogen [median,<0.01 g/L; IQR: <0.01-0.9 g/L), low factor V levels [median,<5%; IQR: <5-4%], low factor VIII levels [median,40%; IQR: 12-79%] and low factor X levels [median, 48%; IQR: 29-67%]. There were smaller reductions in factors II, IX and VII over time. All factors recovered over 48 h post-antivenom. The median INR remained >3 at 6 h post-antivenom but had reduced to <2, by 24 h. The aPTT had also returned to close to normal (<50 sec) at 24 h. Factor VII, VIII and IX levels were unusually high pre-antivenom, median peak concentrations of 393%, 307% and 468% respectively. Pre-antivenom venom concentrations and the INR (r = 0.20, p = 0.02) and aPTT (r = 0.19, p = 0.03) were correlated (non-parametric Spearman analysis). Russell's viper coagulopathy results in prolonged aPTT, INR, low fibrinogen, factors V, VIII and X which recover over 48 h. Severity of clotting abnormalities was associated with venom concentrations.

Effects of pentastarch and albumin infusion on cardiorespiratory function and coagulation in patients with severe sepsis and systemic hypoperfusion.

PubMed

Rackow, E C; Mecher, C; Astiz, M E; Griffel, M; Falk, J L; Weil, M H

1989-05-01

Twenty consecutive patients with severe sepsis were randomized to fluid challenge with 5% albumin or 10% low MW hydroxyethyl starch (pentastarch) solutions. Fluid challenge was administered iv as 250 ml of test colloid every 15 min until the pulmonary artery wedge pressure (WP) was greater than or equal to 15 mm Hg or a maximum dose of 2000 ml was infused. Hemodynamic, respiratory, and coagulation profiles were measured before and after fluid infusion. The amount of colloid required to achieve a WP of 15 mm Hg was comparable between groups. Both colloid infusions resulted in similar increases in cardiac output, stroke output, and stroke work. The effect of fluid infusion with pentastarch on coagulation was not significantly different from albumin, although pentastarch was associated with a 45% decrease in factor VIII:c. We conclude that pentastarch is equivalent to albumin for fluid resuscitation of patients with severe sepsis.

[Influence of cytostatic combination therapy with vincristine sulphate and iphosphamide on blood coagulation].

PubMed

Neidhardt, B; Hartwich, G

1975-02-28

Disorders of blood coagulation were investigated before and during a cytostatic combination therapy with vincristine sulphate and iphosphamide (Asta Z 4942) in 12 patients with malignant tumours or haemoblastoses. Thromboplastin time, partial thromboplastin time, thrombin time, heat-dependent fibrin, clot retraction, and clotting factors II, V, VIII, IX, X, and the platelet count were determined. A change in the plasmatic coagulation system attributable to the combination therapy could not be demonstrated in any patient. The influence of the cytostatic combination on the platelet-dependent haemostasis was small; a decrease in platelet count could be observed in only one patient, in whom an additional causative damage to thrombopoiesis due to the underlying disease could be assumed. Regardless of the cytostatic therapy there were indications of a hypercoagulability in 10 patients. This explains the increased susceptibility of such patients for thromboses or consumption coagulopathy.

ACUTE CARDIOVASCULAR EFFECTS OF FIREFIGHTING AND ACTIVE COOLING DURING REHABILITATION

PubMed Central

Burgess, Jefferey L.; Duncan, Michael D.; Hu, Chengcheng; Littau, Sally R.; Caseman, Delayne; Kurzius-Spencer, Margaret; Davis-Gorman, Grace; McDonagh, Paul F.

2012-01-01

Objectives To determine the cardiovascular and hemostatic effects of fire suppression and post-exposure active cooling. Methods Forty-four firefighters were evaluated prior to and after a 12 minute live-fire drill. Next, 50 firefighters undergoing the same drill were randomized to post-fire forearm immersion in 10°C water or standard rehabilitation. Results In the first study, heart rate and core body temperature increased and serum C-reactive protein decreased but there were no significant changes in fibrinogen, sE-selectin or sL-selectin. The second study demonstrated an increase in blood coagulability, leukocyte count, factors VIII and X, cortisol and glucose, and a decrease in plasminogen and sP-selectin. Active cooling reduced mean core temperature, heart rate and leukocyte count. Conclusions Live-fire exposure increased core temperature, heart rate, coagulability and leukocyte count; all except coagulability were reduced by active cooling. PMID:23090161

[Effects of various adsorbants on coagulation factors (author's transl)].

PubMed

Soulier, J P; Prou-Wartelle, O

1975-01-01

Adsorption of clotting factors by various adsorbants is studied (tricalcium phosphate, baryum sulfate or carbonate or citrate, calcium oxalate, aluminium hydroxyde and several silicate such as: kaolin, celite, bentonite, attapulgite, beidellite, asbestos). The main properties of each adsorbant are listed as well as several applications such as: selective adsorption of fibrinogen, separation between fibrinogen and factor VIII, separation of factor II from the other components of the prothrombin complex. Activation of factors XII and XI by the various silicates, as well as the activation of factor V by attapulgite are studied. Finally, the action of such adsorbants on the fibrinolytic system is summarized.

Anticoagulation beyond direct thrombin and factor Xa inhibitors: indications for targeting the intrinsic pathway?

PubMed

van Montfoort, Maurits L; Meijers, Joost C M

2013-08-01

Antithrombotic drugs like vitamin K antagonists and heparin have been the gold standard for the treatment and prevention of thromboembolic disease for many years. Unfortunately, there are several disadvantages of these antithrombotic drugs: they are accompanied by serious bleeding problems, it is necessary to monitor the therapeutic window, and there are various interactions with food and other drugs. This has led to the development of new oral anticoagulants, specifically inhibiting either thrombin or factor Xa. In terms of effectiveness, these drugs are comparable to the currently available anticoagulants; however, they are still associated with issues such as bleeding, reversal of the drug and complicated laboratory monitoring. Vitamin K antagonists, heparin, direct thrombin and factor Xa inhibitors have in common that they target key proteins of the haemostatic system. In an attempt to overcome these difficulties we investigated whether the intrinsic coagulation factors (VIII, IX, XI, XII, prekallikrein and high-molecular-weight kininogen) are superior targets for anticoagulation. We analysed epidemiological data concerning thrombosis and bleeding in patients deficient in one of the intrinsic pathway proteins. Furthermore, we discuss several thrombotic models in intrinsic coagulation factor-deficient animals. The combined results suggest that intrinsic coagulation factors could be suitable targets for anticoagulant drugs.

Oral and parenteral anticoagulants: new kids on the block.

PubMed

Aditya, S

2012-01-01

Well-documented drawbacks of traditional anticoagulants have lead to the quest for an ideal anticoagulant resulting in a surge of novel anticoagulant molecules. These newer agents directly target specific steps in coagulation cascade and include newer low molecular weight heparins (adomiparin), ultra low molecular weight heparins (semuloparin, RO-14), inhibitors of activated factor II (dabigatran, AZD0837), X (rivaroxaban, apixaban, edoxaban, betrixaban), IX (REG1,2), XI (antisense oligonucleotides, BMS 262084, clavatadine A), VII/tissue factor (tifacogin, PCI 274836, and BMS 593214), V (recomodulin, solulin), VIII (TB402), dual thrombin/factor X inhibitors (EP21709, tanogitran), and newer vitamin K antagonists (tecarfarin). Direct thrombin inhibitors and Factor X inhibitors are the most clinically advanced. This article discusses the recent advances in the development of novel targets of anticoagulants. Medline, EMBASE, cochrane database, medscape, SCOPUS, and clinicaltrials.gov were searched using terms "anticoagulants", "blood coagulation inhibitors", "anticoagulants and venous thromboembolism", "anticoagulants and atrial fibrillation", and "'antithrombins." Journal articles published from 2007 to 2012 discussing pharmacology and/or clinical trials were screened.

Hemostasis in Hypothyroidism and Autoimmune Thyroid Disorders.

PubMed

Ordookhani, Arash; Burman, Kenneth D

2017-04-01

There are contradictory results on the effect of hypothyroidism on the changes in hemostasis. Inadequate population-based studies limited their clinical implications, mainly on the risk of venous thromboembolism (VTE). This paper reviews the studies on laboratory and population-based findings regarding hemostatic changes and risk of VTE in hypothyroidism and autoimmune thyroid disorders. A comprehensive literature search was conducted employing MEDLINE database. The following words were used for the search: Hypothyroidism; thyroiditis, autoimmune; blood coagulation factors; blood coagulation tests; hemostasis, blood coagulation disorders; thyroid hormones; myxedema; venous thromboembolism; fibrinolysis, receptors thyroid hormone. The papers that were related to hypothyroidism and autoimmune thyroid disorder and hemostasis are used in this review. Overt hypothyroidism is more associated with a hypocoagulable state. Decreased platelet count, aggregation and agglutination, von Willebrand factor antigen and activity, several coagulation factors such as factor VIII, IX, XI, VII, and plasminogen activator-1 are detected in overt hypothyrodism. Increased fibrinogen has been detected in subclinical hypothyroidism and autoimmune thyroid disease rendering a tendency towards a hypercoagulability state. Increased factor VII and its activity, and plasminogen activator inhibitor-1 are among several findings contributing to a prothrombotic state in subclinical hypothyroidism. Overt hypothyroidism is associated with a hypocoagulable state and subclinical hypothyroidism and autoimmune thyroid disorders may induce a prothrombotic state. However, there are contradictory findings for the abovementioned thyroid disorders. Prospective studies on the risk of VTE in various levels of hypofunctioning of the thyroid and autoimmune thyroid disorders are warranted.

Hemostasis in Hypothyroidism and Autoimmune Thyroid Disorders

PubMed Central

Ordookhani, Arash; Burman, Kenneth D.

2017-01-01

Context There are contradictory results on the effect of hypothyroidism on the changes in hemostasis. Inadequate population-based studies limited their clinical implications, mainly on the risk of venous thromboembolism (VTE). This paper reviews the studies on laboratory and population-based findings regarding hemostatic changes and risk of VTE in hypothyroidism and autoimmune thyroid disorders. Evidence Acquisition A comprehensive literature search was conducted employing MEDLINE database. The following words were used for the search: Hypothyroidism; thyroiditis, autoimmune; blood coagulation factors; blood coagulation tests; hemostasis, blood coagulation disorders; thyroid hormones; myxedema; venous thromboembolism; fibrinolysis, receptors thyroid hormone. The papers that were related to hypothyroidism and autoimmune thyroid disorder and hemostasis are used in this review. Results Overt hypothyroidism is more associated with a hypocoagulable state. Decreased platelet count, aggregation and agglutination, von Willebrand factor antigen and activity, several coagulation factors such as factor VIII, IX, XI, VII, and plasminogen activator-1 are detected in overt hypothyrodism. Increased fibrinogen has been detected in subclinical hypothyroidism and autoimmune thyroid disease rendering a tendency towards a hypercoagulability state. Increased factor VII and its activity, and plasminogen activator inhibitor-1 are among several findings contributing to a prothrombotic state in subclinical hypothyroidism. Conclusions Overt hypothyroidism is associated with a hypocoagulable state and subclinical hypothyroidism and autoimmune thyroid disorders may induce a prothrombotic state. However, there are contradictory findings for the abovementioned thyroid disorders. Prospective studies on the risk of VTE in various levels of hypofunctioning of the thyroid and autoimmune thyroid disorders are warranted. PMID:29026409

Increased coagulation and fibrinolytic potential of solvent-detergent plasma: a comparative study between Omniplasma and fresh frozen plasma.

PubMed

van Beers, J J B C; van Egmond, L T; Wetzels, R J H; Verhezen, P W M; Beckers, E A M; van Oerle, R; Spronk, H M H; Straat, R J M H E; Henskens, Y M C

2016-07-01

In this study, differences in levels of proteins involved in coagulation and fibrinolysis were compared between fresh frozen (quarantine plasma) and Omniplasma. Furthermore, thawing conditions and plasma stability after thawing were studied. 10 Omniplasma and 10 quarantine plasma units were used to study different procoagulation, anticoagulation and fibrinolytic parameters. Analysis took place at different time-points during plasma storage at 2-6°C. At baseline, significant reduced levels of factor V, free protein S, α2-antiplasmin and tPA-induced ROTEM lysis time were observed in Omniplasma as compared to quarantine plasma. Moreover, thrombin generation, IXa-AT complex levels and factor XIa were significantly increased in Omniplasma. The majority of the parameters studied remained stable in Omniplasma 48 h after thawing, with the exception of factor VIII (decrease) and IXa-AT (increase). Our results suggest an increased coagulation potential, presumingly as a result of contact activation during the production process and also, an increased fibrinolytic potential in Omniplasma. The stability of Omniplasma, based upon the different parameters studied, is comparable to Q-plasma. A maximum post-thawing time of 48 hfor Omniplasma can be suggested. © 2016 International Society of Blood Transfusion.

Comparison of functional aspects of the coagulation cascade in human and sea turtle plasmas.

PubMed

Soslau, Gerald; Wallace, Bryan; Vicente, Catherine; Goldenberg, Seth J; Tupis, Todd; Spotila, James; George, Robert; Paladino, Frank; Whitaker, Brent; Violetta, Gary; Piedra, Rotney

2004-08-01

Functional hemostatic pathways are critical for the survival of all vertebrates and have been evolving for more than 400 million years. The overwhelming majority of studies of hemostasis in vertebrates have focused on mammals with very sparse attention paid to reptiles. There have been virtually no studies of the coagulation pathway in sea turtles whose ancestors date back to the Jurassic period. Sea turtles are often exposed to rapidly altered environmental conditions during diving periods. This may reduce their blood pH during prolonged hypoxic dives. This report demonstrates that five species of turtles possess only one branch of the mammalian coagulation pathway, the extrinsic pathway. Mixing studies of turtle plasmas with human factor-deficient plasmas indicate that the intrinsic pathway factors VIII and IX are present in turtle plasma. These two factors may play a significant role in supporting the extrinsic pathway by feedback loops. The intrinsic factors, XI and XII are not detected which would account for the inability of reagents to induce coagulation via the intrinsic pathway in vitro. The analysis of two turtle factors, factor II (prothrombin) and factor X, demonstrates that they are antigenically/functionally similar to the corresponding human factors. The turtle coagulation pathway responds differentially to both pH and temperature relative to each turtle species and relative to human samples. The coagulation time (prothrombin time) increases as the temperature decreases between 37 and 15 degrees C. The increased time follows a linear relationship, with similar slopes for loggerhead, Kemps ridley and hawksbill turtles as well as for human samples. Leatherback turtle samples show a dramatic nonlinear increased time below 23 degrees C, and green turtle sample responses were similar but less dramatic. All samples also showed increased prothrombin times as the pH decreased from 7.8 to 6.4, except for three turtle species. The prothrombin times decreased, to varying extents, in a linear fashion relative to reduced pH with the rate of change greatest in leatherbacks>green>loggerhead turtles. All studies were conducted with reagents developed for human samples which would impact on the quantitative results with the turtle samples, but are not likely to alter the qualitative results. These comparative studies of the coagulation pathway in sea turtles and humans could enhance our knowledge of structure/function relationships and evolution of coagulation factors.

Contact system activation and high thrombin generation in hyperthyroidism.

PubMed

Kim, Namhee; Gu, Ja-Yoon; Yoo, Hyun Ju; Han, Se Eun; Kim, Young Il; Nam-Goong, Il Sung; Kim, Eun Sook; Kim, Hyun Kyung

2017-05-01

Hyperthyroidism is associated with increased thrombotic risk. As contact system activation through formation of neutrophil extracellular traps (NET) has emerged as an important trigger of thrombosis, we hypothesized that the contact system is activated along with active NET formation in hyperthyroidism and that their markers correlate with disease severity. In 61 patients with hyperthyroidism and 40 normal controls, the levels of coagulation factors (fibrinogen, and factor VII, VIII, IX, XI and XII), D-dimer, thrombin generation assay (TGA) markers, NET formation markers (histone-DNA complex, double-stranded DNA and neutrophil elastase) and contact system markers (activated factor XII (XIIa), high-molecular-weight kininogen (HMWK), prekallikrein and bradykinin) were measured. Patients with hyperthyroidism showed higher levels of fibrinogen (median (interquartile range), 315 (280-344) vs 262 (223-300), P  = 0.001), D-dimer (103.8 (64.8-151.5) vs 50.7 (37.4-76.0), P  < 0.001), peak thrombin (131.9 (102.2-159.4) vs 31.6 (14.8-83.7), P  < 0.001) and endogenous thrombin potential (649 (538-736) vs 367 (197-1147), P  = 0.021) in TGA with 1 pM tissue factor, neutrophil elastase (1.10 (0.39-2.18) vs 0.23 (0.20-0.35), P  < 0.001), factor XIIa (66.9 (52.8-87.0) vs 73.0 (57.1-86.6), P  < 0.001), HMWK (6.11 (4.95-7.98) vs 3.83 (2.60-5.68), P  < 0.001), prekallikrein (2.15 (1.00-6.36) vs 1.41 (0.63-2.22), P  = 0.026) and bradykinin (152.4 (137.6-180.4) vs 118.3 (97.1-137.9), P  < 0.001) than did normal controls. In age- and sex-adjusted logistic regression analysis, fibrinogen, factor VIII, IX and XIIa, D-dimer, peak thrombin, neutrophil elastase, HMWK and bradykinin showed significant odds ratios representing hyperthyroidism's contribution to coagulation and contact system activation. Free T4 was significantly correlated with factors VIII and IX, D-dimer, double-stranded DNA and bradykinin. This study demonstrated that contact system activation and abundant NET formation occurred in the high thrombin generation state in hyperthyroidism and were correlated with free T4 level. © 2017 European Society of Endocrinology.

Separation of whole blood into plasma and red cells by using a hollow-fibre filtration system.

PubMed

Hornsey, V S; McColl, K; Drummond, O; Prowse, C V

2005-08-01

The aim of this study was to assess the separation of whole blood into red cells and plasma by using the Sangofer device, which is a gravity-fed, hollow-fibre system. The components would then be compared with those produced by the use of more elaborate technical equipment. Ten whole-blood units were leucoreduced by using a WBF2 filter and immediately separated into red cells and plasma by using the Sangofer blood-separation device. Red cells were stored in additive solution and tested on days 1 and 42. The plasma was assayed for levels of various coagulation factors and for markers of both coagulation and complement activation. The red-cell parameters were similar to those obtained when routine centrifugation methods were used. The filter did not cause haemolysis. Levels of plasma factor VIII and factor XI were lower than those seen in routinely produced leucoreduced plasma units but there was no evidence of activation of the coagulation and complement systems. The Sangofer device is simple and straightforward to use and eliminates the need for both centrifugation and automated separation steps during the processing of whole blood into red cells and plasma components. Minor changes are required to make the procedure easier to incorporate into routine use.

Differential action of medically important Indian BIG FOUR snake venoms on rodent blood coagulation.

PubMed

Hiremath, Vilas; Nanjaraj Urs, A N; Joshi, Vikram; Suvilesh, K N; Savitha, M N; Urs Amog, Prathap; Rudresha, G V; Yariswamy, M; Vishwanath, B S

2016-02-01

Snakebite is a global health problem affecting millions of people. According to WHO, India has the highest mortality and/or morbidity due to snakebite. In spite of commendable research on Indian BIG FOUR venomous species; Naja naja and Bungarus caeruleus (elapid); Daboia russelii and Echis carinatus (viperid), no significant progress has been achieved in terms of diagnosis and management of biting species with appropriate anti-snake venom. Major hurdle is identification of offending species. Present study aims at differentiation of Indian BIG FOUR snake venoms based on their distinguish action on rodent blood coagulation. Assessment of coagulation alterations by elapid venoms showed negligible effect on re-calcification time, prothrombin time, activated partial thromboplastin time and factors assay (I, II, V, VIII and X) both in vitro and in vivo. However, viperid venoms demonstrated significant anticoagulant status due to their remarkable fibrinogen degradation potentials as supported by fibrinogenolytic activity, fibrinogen zymography and rotational thromboelastometry. Though results provide hint on probable alterations of Indian BIG FOUR snake venoms on blood coagulation, the study however needs validation from human victim's samples to ascertain its reliability for identification of biting snake species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Animal Models of Hemophilia

PubMed Central

Sabatino, Denise E.; Nichols, Timothy C.; Merricks, Elizabeth; Bellinger, Dwight A.; Herzog, Roland W.; Monahan, Paul E.

2013-01-01

The X-linked bleeding disorder hemophilia is caused by mutations in coagulation factor VIII (hemophilia A) or factor IX (hemophilia B). Unless prophylactic treatment is provided, patients with severe disease (less than 1% clotting activity) typically experience frequent spontaneous bleeds. Current treatment is largely based on intravenous infusion of recombinant or plasma-derived coagulation factor concentrate. More effective factor products are being developed. Moreover, gene therapies for sustained correction of hemophilia are showing much promise in pre-clinical studies and in clinical trials. These advances in molecular medicine heavily depend on availability of well-characterized small and large animal models of hemophilia, primarily hemophilia mice and dogs. Experiments in these animals represent important early and intermediate steps of translational research aimed at development of better and safer treatments for hemophilia, such a protein and gene therapies or immune tolerance protocols. While murine models are excellent for studies of large groups of animals using genetically defined strains, canine models are important for testing scale-up and for longer-term follow-up as well as for studies that require larger blood volumes. PMID:22137432

Platelet-targeted gene therapy with human factor VIII establishes haemostasis in dogs with haemophilia A.

PubMed

Du, Lily M; Nurden, Paquita; Nurden, Alan T; Nichols, Timothy C; Bellinger, Dwight A; Jensen, Eric S; Haberichter, Sandra L; Merricks, Elizabeth; Raymer, Robin A; Fang, Juan; Koukouritaki, Sevasti B; Jacobi, Paula M; Hawkins, Troy B; Cornetta, Kenneth; Shi, Qizhen; Wilcox, David A

2013-01-01

It is essential to improve therapies for controlling excessive bleeding in patients with haemorrhagic disorders. As activated blood platelets mediate the primary response to vascular injury, we hypothesize that storage of coagulation Factor VIII within platelets may provide a locally inducible treatment to maintain haemostasis for haemophilia A. Here we show that haematopoietic stem cell gene therapy can prevent the occurrence of severe bleeding episodes in dogs with haemophilia A for at least 2.5 years after transplantation. We employ a clinically relevant strategy based on a lentiviral vector encoding the ITGA2B gene promoter, which drives platelet-specific expression of human FVIII permitting storage and release of FVIII from activated platelets. One animal receives a hybrid molecule of FVIII fused to the von Willebrand Factor propeptide-D2 domain that traffics FVIII more effectively into α-granules. The absence of inhibitory antibodies to platelet-derived FVIII indicates that this approach may have benefit in patients who reject FVIII replacement therapies. Thus, platelet FVIII may provide effective long-term control of bleeding in patients with haemophilia A.

Platelet-targeted gene therapy with human factor VIII establishes haemostasis in dogs with haemophilia A

PubMed Central

Du, Lily M.; Nurden, Paquita; Nurden, Alan T.; Nichols, Timothy C.; Bellinger, Dwight A.; Jensen, Eric S.; Haberichter, Sandra L.; Merricks, Elizabeth; Raymer, Robin A.; Fang, Juan; Koukouritaki, Sevasti B.; Jacobi, Paula M.; Hawkins, Troy B.; Cornetta, Kenneth; Shi, Qizhen; Wilcox, David A.

2013-01-01

It is essential to improve therapies for controlling excessive bleeding in patients with haemorrhagic disorders. As activated blood platelets mediate the primary response to vascular injury, we hypothesize that storage of coagulation Factor VIII within platelets may provide a locally inducible treatment to maintain haemostasis for haemophilia A. Here we show that haematopoietic stem cell gene therapy can prevent the occurrence of severe bleeding episodes in dogs with haemophilia A for at least 2.5 years after transplantation. We employ a clinically relevant strategy based on a lentiviral vector encoding the ITGA2B gene promoter, which drives platelet-specific expression of human FVIII permitting storage and release of FVIII from activated platelets. One animal receives a hybrid molecule of FVIII fused to the von Willebrand Factor propeptide-D2 domain that traffics FVIII more effectively into α-granules. The absence of inhibitory antibodies to platelet-derived FVIII indicates that this approach may have benefit in patients who reject FVIII replacement therapies. Thus, platelet FVIII may provide effective long-term control of bleeding in patients with haemophilia A. PMID:24253479

Hyperthyroidism and cerebral venous thrombosis.

PubMed

Mouton, S; Nighoghossian, N; Berruyer, M; Derex, L; Philippeau, F; Cakmak, S; Honnorat, J; Hermier, M; Trouillas, P

2005-01-01

The demonstration of an underlying prothrombotic condition in cerebral venous thrombosis (CVT) may have important practical consequences in terms of prevention. Thyrotoxicosis through a hypercoagulable state may be a predisposing factor for CVT. The authors present the cases of 4 patients who developed CVT and hyperthyroidism. At the acute stage, hyperthyroidism was associated with an increase in factor VIII (FVIII). At follow-up, FVIII level remained increased in 2 patients. Hyperthyroidism may have an impact on FVIII level. Accordingly in patients with hyperthyroidism and neurological symptoms, the diagnosis of CVT should be considered and an exhaustive coagulation screening may be appropriate. (c) 2005 S. Karger AG, Basel.

In vivo recovery of factor VIII and factor IX: intra- and interindividual variance in a clinical setting.

PubMed

Björkman, S; Folkesson, A; Berntorp, E

2007-01-01

In vivo recovery (IVR) is traditionally used as a parameter to characterize the pharmacokinetic properties of coagulation factors. It has also been suggested that dosing of factor VIII (FVIII) and factor IX (FIX) can be adjusted according to the need of the individual patient, based on an individually determined IVR value. This approach, however, requires that the individual IVR value is more reliably representative for the patient than the mean value in the population, i.e. that there is less variance within than between the individuals. The aim of this investigation was to compare intra- and interindividual variance in IVR (as U dL1 per U kg1) for FVIII and plasma-derived FIX in a cohort of non-bleeding patients with haemophilia. The data were collected retrospectively from six clinical studies, yielding 297 IVR determinations in 50 patients with haemophilia A and 93 determinations in 13 patients with haemophilia B. For FVIII, the mean variance within patients exceeded the between-patient variance. Thus, an individually determined IVR value is apparently no more informative than an average, or population, value for the dosing of FVIII. There was no apparent relationship between IVR and age of the patient (1.5-67 years). For FIX, the mean variance within patients was lower than the between-patient variance, and there was a significant positive relationship between IVR and age (13-69 years). From these data, it seems probable that using an individual IVR confers little advantage in comparison to using an age-specific population mean value. Dose tailoring of coagulation factor treatment has been applied successfully after determination of the entire single-dose curve of FVIII:C or FIX:C in the patient and calculation of the relevant pharmacokinetic parameters. However, the findings presented here do not support the assumption that dosing of FVIII or FIX can be individualized on the basis of a clinically determined IVR value.

Manufacturing challenges in the commercial production of recombinant coagulation factor VIII.

PubMed

Jiang, R; Monroe, T; McRogers, R; Larson, P J

2002-03-01

Advances in gene technology have led to the development of a method to manufacture recombinant coagulation Factor VIII (rFVIII) for haemophilia A. Because rFVIII is a large and complex protein, its commercialization has required that many challenges in manufacturing, purification and processing be overcome. In order to license the first generation of rFVIII (Kogenate) in 1993, Bayer Corporation invested over 10 years in research and manufacturing development. Seven additional years were subsequently devoted to research and manufacturing improvements in order to accomplish the recent licensing of a second rFVIII product (KOGENATE Bayer or Kogenate FS). This product differs from its predecessor, in that human albumin is removed from the purification and the formulation steps. In addition, fewer chromatography steps are involved resulting in greater yields per mL of conditioned medium, and a solvent-detergent viral inactivation step replaces the heat-processing step used for the previous product. Despite these changes in the manufacturing, the protein backbone and carbohydrate structure of the final rFVIII molecule are identical. The complexity of the production processes is reflected by over 100 000 manufacturing data entries and by 600 quality control tests for each batch of rFVIII. Manufacturers are continuing to develop the next generation of rFVIII, which will be produced without the addition of any human or animal proteins or byproducts. Investments in research, development and manufacturing technology are expected to result in the development of new products with enhanced safety profiles, and in an increase in the production capacity for products that are chronically in short supply.

Quality of Clotting Factor Activity in Fresh Frozen Plasma at Thaw with a Microwave System and after Storage at 4 degrees C for 48 Hours.

PubMed

Kuta, Piotr; Hauck-Dlimi, Barbara; Strobel, Julian; Zimmermann, Robert; Eckstein, Reinhold

2016-01-01

Uncontrolled hemorrhage in polytrauma patients usually results in rapid need of blood products. Despite the shorter thawing times of microwave devices for heating fresh frozen plasma (FFP), their use has remained controversial, and just a few laboratory analyses have been published on this topic. The aim of this study was to analyse the quality of clotting factors immediately after thawing FFP with a microwave device and after 48-hour post thaw storage at 4 degrees C. 24 FFP units of all four ABO blood groups (six of each blood group) were thawed with a Transfusio-therm 2000 and later stored at 4 degrees C for 48 hours. Samples were drawn aseptically and investigated on various clotting factors and protein proteases (fibrinogen, antithrombin, FII, FV, FVII, FVIII, FIX, FX, FXI, FXIII, vWF antigen and activity, protein S, and protein C) using standard coagulation and chromogenic assays immediately after thawing and again after a 48-hour storage period at 4 degrees C. All units were tested for both anaerobic and aerobic microbial contamination using standard operating procedures immediately after thawing. After thawing, all coagulation factors and protein protease activities were within normal ranges. Blood group O individuals had approximately 25% lower plasma levels of vWF antigen and activity. After a 48-hour storage period at 4 degrees C, FVIII and FIX activities declined significantly in all blood groups, whereas the remaining clotting factors remained comparably stable. Immediately after rapid thawing using a microwave system, all FFP units contained adequate coagulation factor activities to maintain hemostatic activity at the time of product thaw. The post thaw refrigerated storage caused an anticipated decrease in factor VIII and IX activities, but retained normal coagulation factor levels of many plasma proteins. Therefore we conclude that the Transfusio-therm 2000 has no clinically significant influence on the activity of clotting factors and plasma proteases in FFP units.

Investigational drugs for coagulation disorders.

PubMed

Mannucci, Pier Mannuccio; Mancuso, Maria Elisa

2013-08-01

The current standard treatment in persons with hemophilia (PWH) is prophylaxis, given intravenously twice or thrice weekly, which is associated with a non negligible burden on patients' quality of life. Therefore the main attempts aiming to improve the management of PWH are targeted towards the development of a new generation of coagulation factors endowed with properties facilitating prophylaxis and/or a better control of bleeding. This article summarizes the main results obtained so far in the development of new antihemophilic products, and emphasizes the formidable requirements imposed upon by regulatory agencies to get marketing authorization for new drugs, which make progress in this field difficult. Published literature on new molecules for replacement treatment in hemophilia A and B has been retrieved by using PubMed search and all ongoing clinical trials have been looked for online. New molecules are usually engineered to have a longer plasma half-life but also in some instances a higher potency. The prolongation of half-life may be obtained by using sustained release delivery vehicles, by chemical modification or by creating fusion proteins. Factors VIII, IX and VII have been variably modified in order to obtain improved coagulation products and results from Phase I/II studies are encouraging, particularly for factor IX. However, Phase III studies that should provide evidence on efficacy and effectiveness more cogent for clinical use are still ongoing and results are not yet available.

A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles.

PubMed

Kurosawa, Yuko; Nirengi, Shinsuke; Homma, Toshiyuki; Esaki, Kazuki; Ohta, Mitsuhiro; Clark, Joseph F; Hamaoka, Takafumi

2015-06-25

Our aim was to determine the quantitative effects of a single-dose of Nattokinase (NK) administration on coagulation/fibrinolysis parameters comprehensively in healthy male subjects. A double-blind, placebo-controlled cross-over NK intervention study was carried out in 12 healthy young males. Following the baseline blood draw, each subject was randomized to receive either a single-dose of 2,000 FU NK (NSK-SD, Japan Bio Science Laboratory Co., Ltd) or placebo with subsequent cross-over of the groups. Subjects donated blood samples at 2, 4, 6 and 8 hours following administration for analysis of coagulation/fibrinolysis parameters. As a result, D-dimer concentrations at 6, and 8 hours, and blood fibrin/fibrinogen degradation products at 4 hours after NK administration elevated significantly (p < 0.05, respectively). Factor VIII activity declined at 4 and 6 hours (p < 0.05, respectively), blood antithrombin concentration was higher at 2 and 4 hours (p < 0.05, respectively), and the activated partial thromboplastin time prolonged significantly at 2 and 4 hours following NK administration (p < 0.05 and p < 0.01, respectively). All the changes, however, were within the normal range. In conclusion, thus, a single-dose of NK administration appears enhancing fibrinolysis and anti-coagulation via several different pathways simultaneously.

Interval and continuous exercise regimens suppress neutrophil-derived microparticle formation and neutrophil-promoted thrombin generation under hypoxic stress.

PubMed

Chen, Yi-Ching; Ho, Ching-Wen; Tsai, Hsing-Hua; Wang, Jong-Shyan

2015-04-01

Acute hypoxic exposure increases vascular thrombotic risk. The release of procoagulant-rich microparticles from neutrophils accelerates the pathogenesis of inflammatory thrombosis. The present study explicates the manner in which interval and continuous exercise regimens affect neutrophil-derived microparticle (NDMP) formation and neutrophil/NDMP-mediated thrombin generation (TG) under hypoxic condition. A total of 60 sedentary males were randomized to perform either aerobic interval training [AIT; 3-min intervals at 40% and 80% V̇O2max (maximal O2 consumption)] or moderate continuous training (MCT; sustained 60% V̇O2max) for 30 min/day, 5 days/week for 5 weeks, or to a control (CTL) group who did not receive any form of training. At rest and immediately after hypoxic exercise test (HE, 100 W under 12% O2 for 30 min), the NDMP characteristics and dynamic TG were measured by flow cytometry and thrombinography respectively. Before the intervention, HE (i) elevated coagulant factor VIII/fibrinogen concentrations and shortened activated partial thromboplastin time (aPTT), (ii) increased total and tissue factor (TF)-rich/phosphatidylserine (PS)-exposed NDMP counts and (iii) enhanced the peak height and rate of TG promoted by neutrophils/NDMPs. Following the 5-week intervention, AIT exhibited higher enhancement of V̇O2max than did MCT. Notably, both MCT and AIT attenuated the extents of HE-induced coagulant factor VIII/fibrinogen elevations and aPTT shortening. Furthermore, the two exercise regimens significantly decreased TF-rich/PS-exposed NDMP formation and depressed neutrophil/NDMP-mediated dynamic TG at rest and following HE. Hence, we conclude that AIT is superior to MCT for enhancing aerobic capacity. Moreover, either AIT or MCT effectively ameliorates neutrophil/NDMP-promoted TG by down-regulating expression of procoagulant factors during HE, which may reduce thrombotic risk evoked by hypoxia. Moreover, either AIT or MCT effectively ameliorates neutrophil/NDMP-promoted TG by down-regulating expression of procoagulant factors during HE, which may reduce thrombotic risk evoked by hypoxia.

Coagulation Profile in Patients with Different Etiologies for Cushing Syndrome: A Prospective Observational Study.

PubMed

Tirosh, Amit; Lodish, Maya; Lyssikatos, Charalampos; Belyavskaya, Elena; Feelders, Richard A; Stratakis, Constantine A

2017-05-01

Previous studies reported a higher prevalence of venous-thromboembolic events among patients with Cushing disease (CD) compared to those with ACTH-independent Cushing syndrome (CS) from adrenal sources. The objective of the current study was to evaluate the coagulation profile of patients with CS from different etiologies. A prospective observational study was conducted at a clinical research center. The study included adult patients admitted for evaluation of suspected CS (n=85), that were divided into 3 groups: CD (n=22), ACTH-independent CS from an adrenal tumor/hyperplasia (adrenal CS, n=21), and a control group consisting of subjects with negative screening for CS (rule-out CS, n=42). Coagulation profiles were drawn before and 8.5±4.3 months after surgery (trans-sphenoidal or adrenalectomy, n=18), and included fibrinogen, Factor VIII (FVIII), von Willebrand factor antigen (vWF:Ag), plasminogen activator inhibitor-1 (PAI-1), antithrombin III (ATIII), Protein C (PC), Protein S (PS), α2-antiplasmin (α2AP), and aPTT measurements. Patients with CD had higher baseline mean cortisol levels, ATIII activity and vWF:Ag levels compared with adrenal CS. Differences in ATIII activity and vWF:Ag levels remained even after controlling for BMI, and ATIII after also controlling for 24-h urinary free cortisol collections. Our study showed for the first time the differences in coagulation profiles between various etiologies of CS. We assume that the higher cortisol burden among CD patients may explain the differences found in the coagulation profile as well as the higher risk for VTE compared with primary adrenal CS patients. © Georg Thieme Verlag KG Stuttgart · New York.

Anticoagulant Effect of Sugammadex: Just an In Vitro Artifact.

PubMed

Dirkmann, Daniel; Britten, Martin W; Pauling, Henning; Weidle, Juliane; Volbracht, Lothar; Görlinger, Klaus; Peters, Jürgen

2016-06-01

Sugammadex prolongs activated partial thromboplastin time (aPTT) and prothrombin time (PT) suggestive of anticoagulant effects. To pinpoint its presumed anticoagulant site of action, the authors assessed Sugammadex's impact on a panel of coagulation assays. Sugammadex, Rocuronium, Sugammadex and Rocuronium combined, or saline were added to blood samples from healthy volunteers and analyzed using plasmatic (i.e., aPTT, thrombin time, and fibrinogen concentration) (n = 8 each), PT (quick), activities of plasmatic coagulation factors, and whole blood (extrinsically and intrinsically activated thromboelastometry) assays (n = 18 each). Furthermore, dose-dependent effects of Sugammadex were also assessed (n = 18 each) in diluted Russel viper venom time (DRVVT) assays with low (DRVVT1) and high (DRVVT2) phospholipid concentrations and in a highly phospholipid-sensitive aPTT assay. Sugammadex increased PT (+9.1%; P < 0.0001), aPTT (+13.1%; P = 0.0002), and clotting time in extrinsically (+33.1%; P = 0.0021) and intrinsically (+22.4%; P < 0.0001) activated thromboelastometric assays. Furthermore, activities of factors VIII, IX, XI, and XII decreased (-7%, P = 0.009; -7.8%, P < 0.0001; -6.9%, P < 0.0001; and -4.3%, P = 0.011, respectively). Sugammadex dose-dependently prolonged both DRVVT1 and the highly phospholipid-sensitive aPTT assays, but additional phospholipids in the DRVVT2 assay almost abolished these prolongations. Thrombin time, a thromboelastometric thrombin generation assay, clot firmness, clot lysis, fibrinogen concentration, and activities of other coagulation factors were unaltered. Rocuronium, Sugammadex and Rocuronium combined, and saline exerted no effects. Sugammadex significantly affects various coagulation assays, but this is explainable by an apparent phospholipid-binding effect, suggesting that Sugammadex`s anticoagulant effects are likely an in vitro artifact.

An intronic mutation c.6430-3C>G in the F8 gene causes splicing efficiency and premature termination in hemophilia A.

PubMed

Xia, Zunjing; Lin, Jie; Lu, Lingping; Kim, Chol; Yu, Ping; Qi, Ming

2018-06-01

: Hemophilia A is a bleeding disorder caused by coagulation factor VIII protein deficiency or dysfunction, which is classified into severe, moderate, and mild according to factor clotting activity. An overwhelming majority of missense and nonsense mutations occur in exons of F8 gene, whereas mutations in introns can also be pathogenic. This study aimed to investigate the effect of an intronic mutation, c.6430-3C>G (IVS22-3C>G), on pre-mRNA splicing of the F8 gene. We applied DNA and cDNA sequencing in a Chinese boy with hemophilia A to search if any pathogenic mutation in the F8 gene. Functional analysis was performed to investigate the effect of an intronic mutation at the transcriptional level. Human Splicing Finder and PyMol were also used to predict its effect. We found the mutation c.6430-3C>G (IVS22-3C>G) in the F8 gene in the affected boy, with his mother being a carrier. cDNA from the mother and pSPL3 splicing assay showed that the mutation IVS22-3C>G results in a two-nucleotide AG inclusion at the 3' end of intron 22 and leads to a truncated coagulation factor VIII protein, with partial loss of the C1 domain and complete loss of the C2 domain. The in-silico tool predicted that the mutation induces altered pre-mRNA splicing by using a cryptic acceptor site in intron 22. The IVS22-3C>G mutation was confirmed to affect pre-mRNA splicing and produce a truncated protein, which reduces the stability of binding between the F8 protein and von Willebrand factor carrier protein due to the loss of an interaction domain.

Procoagulant imbalance in patients with non-alcoholic fatty liver disease.

PubMed

Tripodi, Armando; Fracanzani, Anna L; Primignani, Massimo; Chantarangkul, Veena; Clerici, Marigrazia; Mannucci, Pier Mannuccio; Peyvandi, Flora; Bertelli, Cristina; Valenti, Luca; Fargion, Silvia

2014-07-01

Non-alcoholic fatty liver disease (NAFLD) is characterized by increased risk of cardiovascular events and liver-fibrosis. Both could be explained by a procoagulant-imbalance that was surmised but never directly demonstrated. We investigated 113 patients with varying histological liver damage [steatosis (n=32), steatohepatitis (n=51), metabolic-cirrhosis (n=30)], 54 with alcoholic/viral-cirrhosis and 179 controls. Plasma was evaluated for levels of pro- and anti-coagulants, and for thrombin-generation assessed as endogenous-thrombin-potential (ETP) with and without thrombomodulin or Protac® as protein C activators. The procoagulant-imbalance was defined as ETP-ratio (with-to-without thrombomodulin) or as Protac®-induced-coagulation-inhibition (PICI%). High ETP-ratios or low PICI% indicate resistance to thrombomodulin or Protac® and hence a procoagulant-imbalance. ETP-ratio increased from controls [0.57 (0.11-0.89)] to steatosis [0.72 (0.33-0.86)] and metabolic-cirrhosis [0.80 (0.57-0.95)], (p<0.001), the latter being comparable to that for alcoholic/viral-cirrhosis [0.80 (0.57-0.95) vs. 0.80 (0.44-0.96)]. Factor VIII (a potent procoagulant for thrombin-generation) increased from steatosis [99% (71-150)] to metabolic-cirrhosis [157% (64-232)], p<0.001. Protein C (a powerful anticoagulant) decreased from steatosis [103% (77-228)] to metabolic-cirrhosis [77 (17-146)], p<0.001. As a consequence, factor VIII-to-protein C ratio increased from steatosis [0.96 (0.36-1.60)] to metabolic-cirrhosis [2.05 (0.81-12.1)], p<0.001 and was correlated with the ETP-ratio (rho=0.543, p<0.001). Similar results were obtained for PICI%. Patients with procoagulant-imbalance detected as ETP-ratio greater or PICI% lower than the median value of controls tended to have a higher risk of metabolic-syndrome, higher intima-media thickness, fibrosis, steatosis or lobular inflammation, all considered clinical manifestations of NAFLD. NAFLD is characterized by a procoagulant-imbalance progressing from the less severe (steatosis) to the most severe form of the disease (metabolic-cirrhosis). This imbalance appears to result from increased factor VIII and reduced protein C and might play a role in the risk of cardiovascular events and liver-fibrosis commonly observed in NAFLD. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

First report of real-time monitoring of coagulation function potential and IgG subtype of anti-FVIII autoantibodies in a child with acquired hemophilia A associated with streptococcal infection and amoxicillin.

PubMed

Takeyama, Masahiro; Nogami, Keiji; Kajimoto, Takahiro; Ogiwara, Kenichi; Matsumoto, Tomoko; Shima, Midori

2018-01-01

We describe an 8-year-old boy with acquired hemophilia A (AHA) associated with streptococcal infection and amoxicillin. Laboratory data revealed low factor VIII activity (FVIII:C, 1.5 IU/dl), and FVIII inhibitor (15.9 BU/ml). Comprehensive coagulation function assays, including rotation thromboelastometry (ROTEM ® ), revealed a markedly prolonged clotting time. Thrombin and plasmin generation (TG/PG) appeared to be moderately impaired. The inhibitor epitope of his anti-FVIII autoantibody recognized light and heavy chains. He was treated with Novoseven ® and prednisolone, resulting in rapid improvement. ROTEM showed the return of coagulation time to normal level on day 20, and TG gradually improved. PG was moderately reduced in the clinical early phase, but improved at day 20. The patient's IgG subtype was IgG 4 at onset. IgG 1 was transiently positive on day 20, but negative on day 46. FVIII inhibitor gradually decreased and was completely absent after day 46, along with the elevated FVIII:C. IgG4 was again elevated on day 83, followed by a rapid decrease, indicative of the presence of non-neutralizing antibody, which remains currently undetected. We for the first time report changes in comprehensive coagulation function and IgG subtype of anti-FVIII antibody in a rare pediatric case of AHA.

A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles

PubMed Central

Kurosawa, Yuko; Nirengi, Shinsuke; Homma, Toshiyuki; Esaki, Kazuki; Ohta, Mitsuhiro; Clark, Joseph F.; Hamaoka, Takafumi

2015-01-01

Our aim was to determine the quantitative effects of a single-dose of Nattokinase (NK) administration on coagulation/fibrinolysis parameters comprehensively in healthy male subjects. A double-blind, placebo-controlled cross-over NK intervention study was carried out in 12 healthy young males. Following the baseline blood draw, each subject was randomized to receive either a single-dose of 2,000 FU NK (NSK-SD, Japan Bio Science Laboratory Co., Ltd) or placebo with subsequent cross-over of the groups. Subjects donated blood samples at 2, 4, 6 and 8 hours following administration for analysis of coagulation/fibrinolysis parameters. As a result, D-dimer concentrations at 6, and 8 hours, and blood fibrin/fibrinogen degradation products at 4 hours after NK administration elevated significantly (p < 0.05, respectively). Factor VIII activity declined at 4 and 6 hours (p < 0.05, respectively), blood antithrombin concentration was higher at 2 and 4 hours (p < 0.05, respectively), and the activated partial thromboplastin time prolonged significantly at 2 and 4 hours following NK administration (p < 0.05 and p < 0.01, respectively). All the changes, however, were within the normal range. In conclusion, thus, a single-dose of NK administration appears enhancing fibrinolysis and anti-coagulation via several different pathways simultaneously. PMID:26109079

Industrial production of clotting factors: Challenges of expression, and choice of host cells.

PubMed

Kumar, Sampath R

2015-07-01

The development of recombinant forms of blood coagulation factors as safer alternatives to plasma derived factors marked a major advance in the treatment of common coagulation disorders. These are complex proteins, mostly enzymes or co-enzymes, involving multiple post-translational modifications, and therefore are difficult to express. This article reviews the nature of the expression challenges for the industrial production of these factors, vis-à-vis the translational and post-translational bottlenecks, as well as the choice of host cell lines for high-fidelity production. For achieving high productivities of vitamin K dependent proteins, which include factors II (prothrombin), VII, IX and X, and protein C, host cell limitation of γ-glutamyl carboxylation is a major bottleneck. Despite progress in addressing this, involvement of yet unidentified protein(s) impedes a complete cell engineering solution. Human factor VIII expresses at very low levels due to limitations at several steps in the protein secretion pathway. Protein and cell engineering, vector improvement and alternate host cells promise improvement in the productivity. Production of Von Willebrand factor is constrained by its large size, complex structure, and the need for extensive glycosylation and disulfide-bonded oligomerization. All the licensed therapeutic factors are produced in CHO, BHK or HEK293 cells. While HEK293 is a recent adoption, BHK cells appear to be disfavored. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Haemostatic profile of healthy premature small for gestational age neonates.

PubMed

Mitsiakos, George; Giougi, Evaggelia; Chatziioannidis, Ilias; Karagianni, Paraskevi; Papadakis, Emmanouil; Tsakalidis, Christos; Papaioannou, Georgia; Malindretos, Pavlos; Nikolaidis, Nikolaos

2010-08-01

The pathogenetic profile of premature Small for Gestational Age (SGA) neonates is strongly related to their haemostatic equilibrium, which is inadequately understood. To evaluate coagulation and fibrinolysis in premature SGA neonates before intervening with Vitamin K administration. We performed a comparison of coagulation, natural inhibitors and fibrinolysis between SGA and Appropriate for Gestational Age (AGA) infants born prematurely [gestational age (G.A.) <37 weeks]. Study population consisted of 139 preterm newborns, 68 of whom were SGA (25 males and 43 females), while 71 were AGA (37 males and 34 females) that consisted the control group. Blood samples were obtained within 30 minutes following birth and before the administration of vitamin K. Investigation included: PT, INR, APTT, fibrinogen, coagulation factors II, V, VII, VIII, IX, X, XI, XII, von Willebrand factor, protein C and free protein S, antithrombin (AT), APCR, tPA and PAI-1. The independent t-test and the Mann-Whitney U test were used to compare the differences between the values of haemostatic parameters. Premature SGA infants presented significantly lower levels of fibrinogen (p<0.029) and higher levels of VIIIc factor, APCR, tPA and PAI-1 (p<0.041, 0.017, 0.021 and 0.019 respectively). The two groups had similar demographic characteristics (except from birth weight), without significant differences in the values of other haemostatic parameters. Despite the statistically significant differentiation in the levels of fibrinogen, VIIIc factor, APCR, tPA and PAI-1, the rest of haemostatic parameters have similar values between SGA and AGA preterms. (c) 2010 Elsevier Ltd. All rights reserved.

Short-term chamber exposure to low doses of two kinds of wood smoke does not induce systemic inflammation, coagulation or oxidative stress in healthy humans

PubMed Central

Sallsten, Gerd; Almerud, Pernilla; Basu, Samar; Barregard, Lars

2013-01-01

Introduction: Air pollution increases the risk of cardiovascular diseases. A proposed mechanism is that local airway inflammation leads to systemic inflammation, affecting coagulation and the long-term risk of atherosclerosis. One major source of air pollution is wood burning. Here we investigate whether exposure to two kinds of wood smoke, previously shown to cause airway effects, affects biomarkers of systemic inflammation, coagulation and lipid peroxidation. Methods: Thirteen healthy adults were exposed to filtered air followed by two sessions of wood smoke for three hours, one week apart. One session used smoke from the start-up phase of the wood-burning cycle, and the other smoke from the burn-out phase. Mean particle mass concentrations were 295 µg/m3 and 146 µg/m3, and number concentrations were 140 000/cm3 and 100 000/cm3, respectively. Biomarkers were analyzed in samples of blood and urine taken before and several times after exposure. Results after wood smoke exposure were adjusted for exposure to filtered air. Results: Markers of systemic inflammation and soluble adhesion molecules did not increase after wood smoke exposure. Effects on markers of coagulation were ambiguous, with minor decreases in fibrinogen and platelet counts and mixed results concerning the coagulation factors VII and VIII. Urinary F2-isoprostane, a consistent marker of in vivo lipid peroxidation, unexpectedly decreased after wood smoke exposure. Conclusions: The effects on biomarkers of inflammation, coagulation and lipid peroxidation do not indicate an increased risk of cardiovascular diseases in healthy adults by short-term exposure to wood smoke at these moderate doses, previously shown to cause airway effects. PMID:23808634

Should anti-inhibitor coagulant complex and tranexamic acid be used concomitantly?

PubMed

Valentino, L A; Holme, P A

2015-11-01

Inhibitor development in haemophilia patients is challenging especially when undergoing surgical procedures. The development of an inhibitor precludes using factor VIII (FVIII) therapy thereby requiring a bypassing agent (BPA) for surgical bleeding prophylaxis if the FVIII inhibitor titre >5 BU. Concomitant use of anti-inhibitor coagulant complex (AICC) and tranexamic acid has been reported in the literature as a beneficial treatment for this population. Anti-inhibitor coagulant complex is known to cause an increase in thrombin generation and tranexamic acid inhibits fibrinolysis. Hence, the combined used of AICC and tranexamic acid has been limited due to safety concerns over possibilities of increased risk of thrombotic events and disseminated intravascular coagulation. However, the rationale for concomitant therapy is to obtain a potential synergistic effect and to increase clot stability. We conducted a literature review of past studies and individual case reports of concomitant use of AICC and tranexamic acid, which was extensively used during dental procedures. Evidence also exists for concomitant use of the combined therapy in orthopaedic procedures, control of gastrointestinal bleeding, epistaxis and cerebral haemorrhages. Some patients who received the combined therapy had failed monotherapy with a single BPA prior to combined therapy. There were no reports of thrombotic complications related to the concomitant therapy and haemostasis was achieved in all cases. Anti-inhibitor coagulant complex and tranexamic acid therapy was found to be safe, well-tolerated and effective therapy in haemophilia patients with inhibitors. Additional randomized controlled studies should be performed to confirm these findings. © 2015 John Wiley & Sons Ltd.

Blood coagulation, fibrinolytic activity and lipid profile in subclinical thyroid disease: subclinical hyperthyroidism increases plasma factor X activity.

PubMed

Erem, Cihangir

2006-03-01

Various abnormalities of coagulation and fibrinolysis occur in patients with thyroid diseases, and may range from subclinical laboratory abnormalities to clinically significant disorders of coagulation and, rarely, major haemorrhage or thromboembolism. The influence of subclinical hypothyroidism (SHypo) on haemostasis is controversial, both hypercoagulable and hypocoagulable states have been reported. A hypercoagulable state might be a risk factor for thromboembolic disease in SHypo. On the other hand, subclinical hyperthyroidism (SCHyper) is associated with enhanced cardiovascular risk. In the English literature, there are no studies on changes in coagulation and fibriolytic status in subjects with SCHyper. Therefore, the aim of the present study was to investigate the markers of endogenous coagulation and fibrinolysis, and to evaluate the relationships between serum lipid profile and thyroid hormones and these haemostatic parameters in subclinical thyroid patients. Various haemostatic parameters were investigated in 30 patients with SHypo and 20 patients with SCHyper and compared to 20 euthyroid controls. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, factors V, VII, VIII, IX and X activities, vWF, antithrombin III (AT III), protein C, protein S, tissue plasminogen activator (t-PA) and tissue plasminogen activator inhibitor-1 (PAI-1), as well as common lipid variables, were measured. The relationships between serum thyroid hormones and these haemostatic parameters were examined. Compared with the control subjects, only FX activity was significantly increased in patients with SCHyper (P < 0.01). Total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels were significantly higher in patients with SHypo compared with the control group (P < 0.001 and P < 0.01, respectively). TC levels were significantly higher in patients with SCHyper than in controls (P < 0.05). No differences could be found in coagulation/fibrinolysis parameters between subclinical hypothyroid patients and control subjects. In patients with SCHyper, serum TSH level was positively correlated with FX activity (r: 0.58, P < 0.01) and inversely correlated with PAI-1 (r: -0.55. P < 0.05). Serum TG levels were inversely correlated with plasma activities of factors V, VII, VIII, IX, X and vWF (r: -0.83, P < 0.001; r: -0.68, P < 0.05; r: -0.61, P < 0.05; r: -0.77, P < 0.01; r: -0.63, P < 0.05; r: -0.60, P < 0.05, respectively). Serum TC levels were positively correlated with plasma fibrinogen levels (r: 0.72, P < 0.05). Serum HDL-C levels were positively correlated with protein S activity (r: 0.68, P < 0.05) and negatively correlated with F VII activity (r: -0.69, P < 0.05). Also, in patients with SHypo, serum TG levels were positively correlated with serum TSH levels (r: 0.42, P < 0.05), plasma activities of factors V, VII and X (r: 0.42, P < 0.05; r: 0.54, P < 0.01; r: 0.57, P < 0.01, respectively) and negatively correlated with plasma fibrinogen levels (r: -0.41, P < 0.05). Serum TC levels were positively correlated with factors V and X (r: 0.42, P < 0.05; r: 0.58, P < 0.01, respectively) and negatively correlated with t-PA Ag levels (r: -0.44, P < 0.05). Serum HDL-C levels were inversely correlated with F VII activity (r: -0.48, P < 0.05). Some differences were found in the haemostatic parameters and lipid profile between the subclinical thyroid patients and healthy controls. Increased factor X activity in patients with subclinical hyperthyroidism represent a potential hypercoagulable state, which might augment the already existing risk for atheroscleroic complications. Also, subclinical hypothyroid patients exhibit a more atherogenic lipid profile compared with healthy individuals. Therefore, subclinical hypothyroidism is also associated with an increased risk of cardiovascular disease. However, thyroid hormones may play a role at different levels of the complex haemostatic system in subclinical thyroid disease.

Determinants of drug costs in hopitalised patients with haemophilia: impact of recombinant activated factor VII.

PubMed

Galanaud, Jean Philippe; Pelletier-Fleury, Nathalie; Logerot-Lebrun, Hélène; Lambert, Thierry

2003-01-01

To analyse the determinants of anti-haemophilic drug costs in hospitalised patients with haemophilia and to estimate the impact of recombinant activated factor VII (rFVIIa) therapy on this expenditure. The perspective of the study was from the viewpoint of the hospital. A prospective study was carried out. All patients with haemophilia who were hospitalised in 1999 in Bicêtre public hospital, Paris, France were included in the cohort. For each of the 96 patients (154 hospital stays), we estimated the costs of anti-haemophilic drugs (coagulation concentrates) used. Costs were then stratified by different variables (severity of the disease, presence of a circulating inhibitor to coagulation factors, etc.) and a multivariate model was developed to determine the relationship between these variables and total anti-haemophilic drug costs, while controlling for potential confounders. Our study revealed: (i) the independent role of the five following variables in contributing to high anti-haemophilic drug expenditure: presence of a circulating inhibitor to coagulation factors, odds ratio (OR) = 16.9 (95% CI: 4.3-66); severity of the disease (factor VIII or factor IX < or =0.01 IU/mL), OR = 3.7 (95% CI: 1.6-8.6); length of hospital stay >4 days, OR = 8 (95% CI: 2.2-29.4); age >18 years old, OR = 6.2 (95% CI: 1.6-24.5); and surgical reasons for hospitalisation (whether surgery was haemophilia related [OR = 35.7 (95% CI: 7.3-175)] or not [OR = 5.4 (95% CI: 1.3-22.5)]); (ii) the large share that rFVIIa represented in this expenditure on medicines: rFVIIa was used in 20.1% of hospital stays and accounted for 56.2% of the total anti-haemophilic drug costs, which were estimated at 4,384,732 Euros (2000 values). Our data underline the heavy cost of the treatment of haemophilic patients with an inhibitor to coagulation factors. But, to the question of whether the high expenditure linked to rFVIIa utilisation will be balanced out by later benefits, it is not yet possible to reply with any certainty; further cost-benefit evaluation should be carried out.

Statistical analysis plan for the WOMAN-ETAPlaT study: Effect of tranexamic acid on platelet function and thrombin generation

PubMed Central

Dallaku, Kastriot; Shakur, Haleema; Edwards, Phil; Beaumont, Danielle; Roberts, Ian; Huque, Sumaya; Delius, Maria; Mansmann, Ulrich

2017-01-01

Background. Postpartum haemorrhage (PPH) is a potentially life-threatening complication for women, and the leading cause of maternal mortality. Tranexamic acid (TXA) is an antifibrinolytic used worldwide to treat uterine haemorrhage and to reduce blood loss in general surgery. TXA may have effects on thrombin generation, platelet function and coagulation factors as a result of its inhibition on the plasmin. Methods. WOMAN ETAPlaT is a sub-study of the World Maternal Antifibrinolitic trial (WOMAN trial). All adult women clinically diagnosed with PPH after a vaginal delivery or caesarean section, are eligible for inclusion in the study. Blood samples will be collected at the baseline and 30 minutes after the first dose of study treatment is given. Platelet function will be evaluated in whole blood immediately after sampling with Multiplate® tests (ADPtest and TRAPtest). Thrombin generation, fibrinogen, D-dimer, and coagulation factors vW, V and VIII will be analysed using platelet poor plasma. Results. Recruitment to WOMAN ETAPlaT started on 04 November 2013 and closed on 13 January 2015, during this time  188 patients were recruited. The final participant follow-up was completed on 04 March 2015. This article introduces the statistical analysis plan for the study, without reference to unblinded data.   Conclusion. The data from this study will provide evidence for the effect of TXA on thrombin generation, platelet function and coagulation factors in women with PPH. Trial registration: ClinicalTrials.gov Identifier: NCT00872469; ISRCTN76912190 PMID:28413832

Acquired hemophilia A: a review of recent data and new therapeutic options.

PubMed

Franchini, Massimo; Vaglio, Stefania; Marano, Giuseppe; Mengoli, Carlo; Gentili, Sara; Pupella, Simonetta; Liumbruno, Giancarlo Maria

2017-10-01

Acquired hemophilia A (AHA) is a rare, but potentially life-threatening, bleeding disorder caused by an autoantibody against factor VIII that interferes with its coagulant function. We performed a narrative review focusing on the diagnostic aspects of AHA and on the current treatment strategies with particular regard to new data and therapeutic developments. The management of this severe hemorrhagic disorder is based on the control of bleeding with the use of bypassing agents and on the utilization of a variety of immunosuppressant agents with the goal of eliminating the autoantibody permanently. The optimal management of AHA should be multidisciplinary and requires a close collaboration between physicians from various specialties.

Traumatic Hemarthrosis of the Knee Secondary to Hemophilia A in a Collegiate Soccer Player: A Case Report

PubMed Central

Fiala, Kelly A.; Hoffmann, Sandra J.; Ritenour, Donna M.

2002-01-01

Objective: To present the case of a collegiate soccer player who suffered from a traumatic knee hemarthrosis secondary to hemophilia A. This case presents an opportunity to discuss the participation status of athletes with hemophilia. Background: Hemophilia is a hereditary blood disease characterized by impaired coagulability of the blood. Hemophilia A is the most common of the severe, inherited bleeding disorders. This type, also called classic hemophilia, is due to a deficiency of clotting factor VIII. The athlete with hemophilia A reported pain and loss of function of his knee during a soccer game despite the absence of injury. Differential Diagnosis: Anterior cruciate ligament tear, intra-articular fracture, meniscus tear, capsular tear, hemarthrosis. Treatment: After the injury, the athlete was admitted to the hospital, where his knee joint was aspirated and he was infused with factor VIII. Later, he participated in traditional knee rehabilitation and was returned to play at the discretion of the orthopaedist and the hematologist. Uniqueness: In past participation guidelines, individuals with bleeding disorders were disqualified from athletic participation; however, with advances in medical care, these individuals may be permitted to participate in accordance with the law. Conclusions: Individuals with hemophilia participate in athletics; therefore, team physicians and athletic trainers must be prepared to care for these individuals. PMID:12937588

Clinical characteristics and outcomes of acquired hemophilia A: experience at a single center in Japan.

PubMed

Ogawa, Yoshiyuki; Yanagisawa, Kunio; Uchiumi, Hideki; Ishizaki, Takuma; Mitsui, Takeki; Gouda, Fumito; Ieko, Masahiro; Ichinose, Akitada; Nojima, Yoshihisa; Handa, Hiroshi

2017-07-01

Acquired hemophilia A (AHA), which is caused by autoantibodies against coagulation factor VIII (FVIII) is a rare, life-threatening bleeding disorder, the incidence of which appears to be increasing in Japan as the population ages. However, the clinical characteristics, treatment, and outcomes of AHA remain difficult to establish due to the rarity of this disease. We retrospectively analyzed data from 25 patients (median age 73 years; range 24-92 years; male n = 15) diagnosed with AHA between 1999 and 2015 at Gunma University Hospital. We identified autoimmune diseases and malignancy as underlying conditions in four and three patients, respectively. Factor VIII activity was significantly decreased in all patients (median 2.0%; range <1.0-8.0) by FVIII inhibitor (median 47.0 BU/mL; range 2.0-1010). Among 71 bleeding events, subcutaneous or intramuscular hemorrhage was the most prevalent. Seventeen patients required bypassing agents. Twenty-two (91.7%) of 24 patients treated with immunosuppressive agents achieved complete response (CR) during a median of 57.5 days (range 19-714 days). Although three patients (12%) relapsed and seven (28%) died of infection, none of the deaths were related to bleeding. Although most of our patients achieved CR after immunosuppressive therapy, the rate of infection-related mortality was unsatisfactorily high.

Manufacturing process used to produce long-acting recombinant factor VIII Fc fusion protein.

PubMed

McCue, Justin; Kshirsagar, Rashmi; Selvitelli, Keith; Lu, Qi; Zhang, Mingxuan; Mei, Baisong; Peters, Robert; Pierce, Glenn F; Dumont, Jennifer; Raso, Stephen; Reichert, Heidi

2015-07-01

Recombinant factor VIII Fc fusion protein (rFVIIIFc) is a long-acting coagulation factor approved for the treatment of hemophilia A. Here, the rFVIIIFc manufacturing process and results of studies evaluating product quality and the capacity of the process to remove potential impurities and viruses are described. This manufacturing process utilized readily transferable and scalable unit operations and employed multi-step purification and viral clearance processing, including a novel affinity chromatography adsorbent and a 15 nm pore size virus removal nanofilter. A cell line derived from human embryonic kidney (HEK) 293H cells was used to produce rFVIIIFc. Validation studies evaluated identity, purity, activity, and safety. Process-related impurity clearance and viral clearance spiking studies demonstrate robust and reproducible removal of impurities and viruses, with total viral clearance >8-15 log10 for four model viruses (xenotropic murine leukemia virus, mice minute virus, reovirus type 3, and suid herpes virus 1). Terminal galactose-α-1,3-galactose and N-glycolylneuraminic acid, two non-human glycans, were undetectable in rFVIIIFc. Biochemical and in vitro biological analyses confirmed the purity, activity, and consistency of rFVIIIFc. In conclusion, this manufacturing process produces a highly pure product free of viruses, impurities, and non-human glycan structures, with scale capabilities to ensure a consistent and adequate supply of rFVIIIFc. Copyright © 2015 Biogen. Published by Elsevier Ltd.. All rights reserved.

Cross-reacting Material-positive Hemophilia A Diagnosed in a Patient with a Spontaneous Thigh Hemorrhage

PubMed Central

Saito, Tatsuya; Mukae, Jyunichi; Nakamura, Yosuke; Inaba, Hiroshi; Nogami, Keiji; Koyama, Takatoshi; Fukutake, Katsuyuki; Yamamoto, Koh

2017-01-01

A 53-year-old man, who had been diagnosed with mild hemophilia A (HA) at 35 years of age, was hospitalized with a thigh hematoma. His bleeding continued despite the administration of recombinant factor VIII (FVIII). The results of an FVIII/von Willebrand factor binding assay were normal. The patient's FVIII coagulant activity (FVIII:C) was low, but his FVIII antigen levels were within the normal limits, suggesting FVIII protein dysfunction. The FVIII:C measurements obtained by one-stage clotting and chromogenic assays were different. An FVIII gene analysis revealed a missense mutation p.Ser308Leu, which is rare in Japan. This case highlights that gene analyses and chromogenic assays are necessary to interpret the discrepancies between FVIII:C and the bleeding phenotype of patients with mild HA. PMID:28674365

Cross-reacting Material-positive Hemophilia A Diagnosed in a Patient with a Spontaneous Thigh Hemorrhage.

PubMed

Saito, Tatsuya; Mukae, Jyunichi; Nakamura, Yosuke; Inaba, Hiroshi; Nogami, Keiji; Koyama, Takatoshi; Fukutake, Katsuyuki; Yamamoto, Koh

2017-01-01

A 53-year-old man, who had been diagnosed with mild hemophilia A (HA) at 35 years of age, was hospitalized with a thigh hematoma. His bleeding continued despite the administration of recombinant factor VIII (FVIII). The results of an FVIII/von Willebrand factor binding assay were normal. The patient's FVIII coagulant activity (FVIII:C) was low, but his FVIII antigen levels were within the normal limits, suggesting FVIII protein dysfunction. The FVIII:C measurements obtained by one-stage clotting and chromogenic assays were different. An FVIII gene analysis revealed a missense mutation p.Ser308Leu, which is rare in Japan. This case highlights that gene analyses and chromogenic assays are necessary to interpret the discrepancies between FVIII:C and the bleeding phenotype of patients with mild HA.

Advanced therapies for the treatment of hemophilia: future perspectives.

PubMed

Liras, Antonio; Segovia, Cristina; Gabán, Aline S

2012-12-13

Monogenic diseases are ideal candidates for treatment by the emerging advanced therapies, which are capable of correcting alterations in protein expression that result from genetic mutation. In hemophilia A and B such alterations affect the activity of coagulation factors VIII and IX, respectively, and are responsible for the development of the disease. Advanced therapies may involve the replacement of a deficient gene by a healthy gene so that it generates a certain functional, structural or transport protein (gene therapy); the incorporation of a full array of healthy genes and proteins through perfusion or transplantation of healthy cells (cell therapy); or tissue transplantation and formation of healthy organs (tissue engineering). For their part, induced pluripotent stem cells have recently been shown to also play a significant role in the fields of cell therapy and tissue engineering. Hemophilia is optimally suited for advanced therapies owing to the fact that, as a monogenic condition, it does not require very high expression levels of a coagulation factor to reach moderate disease status. As a result, significant progress has been possible with respect to these kinds of strategies, especially in the fields of gene therapy (by using viral and non-viral vectors) and cell therapy (by means of several types of target cells). Thus, although still considered a rare disorder, hemophilia is now recognized as a condition amenable to gene therapy, which can be administered in the form of lentiviral and adeno-associated vectors applied to adult stem cells, autologous fibroblasts, platelets and hematopoietic stem cells; by means of non-viral vectors; or through the repair of mutations by chimeric oligonucleotides. In hemophilia, cell therapy approaches have been based mainly on transplantation of healthy cells (adult stem cells or induced pluripotent cell-derived progenitor cells) in order to restore alterations in coagulation factor expression.

Factor (F)VIII/VIIa enhances global haemostatic function in the co-presence of bypassing agents and FVIII among patients with haemophilia A with inhibitor.

PubMed

Nogami, Keiji; Matsumoto, Tomoko; Yada, Koji; Ogiwara, Kenichi; Furukawa, Shoko; Shida, Yasuaki; Takeyama, Masahiro; Shima, Midori

2018-05-01

Bypassing therapy is essential for the haemostatic management of patients with haemophilia A with inhibitor (PWHA-inh), but the therapeutic effects are inconsistent. We previously reported that activated prothrombin complex concentrates (aPCC) activated factor (F)VIIIin vitro, and was mediated mainly by the activated FVII (FVIIa) contained in aPCC. We have extended those studies to assess global coagulation in whole blood from 18 PWHA-inh in the co-presence of aPCC and FVIII using Ca 2+ -triggered rotational thromboelastometry. The clot times (CTs) in the presence of both aPCC (0·05 iu/ml) and recombinant (r)FVIII (1 iu/ml) ex vivo were shortened compared to the aPCC alone (P < 0·01). These enhancing effects of rFVIII were observed, irrespective of recognizing inhibitor epitopes; however, the clot formation time and 'α'-angle were not significantly different. In samples from 7 PWHA-inh post-infusion of aPCC (70-80 iu/kg), only the CTs were shortened in the presence of rFVIIIex vivo compared to its absence (P < 0·05), indicating that the enhanced activity centred on the initiation phase of coagulation. Furthermore, experiments in the co-presence of rFVIIa and rFVIII demonstrated that FVIII accelerated only the CTs. We concluded that FVIII/FVIIa-related coagulation mechanism enhanced global haemostatic function by the co-presence of bypassing agents and FVIII in PWHA-inh. © 2018 John Wiley & Sons Ltd.

Enzymatic and chemical synthesis of new anticoagulant peptides.

PubMed

Origone, Anabella; Bersi, Grisel; Illanes, Andrés; Sturniolo, Héctor; Liggieri, Constanza; Guzmán, Fanny; Barberis, Sonia

2018-06-08

In this study we report the enzymatic synthesis of N-α-[Carbobenzyloxy]-Tyr-Gln-Gln (Z-YQQ), a new anticoagulant tripeptide. It was obtained using phytoproteases from the stems and petioles of Asclepias curassavica L. as catalyst in an aqueous-organic biphasic system formed by 50% (v/v) ethyl acetate and 0.1 M Tris - HCl buffer pH 8. The resulting peptide was compared with the analogous peptide Tyr-Gln-Gln (YQQ) produced by solid-phase chemical synthesis. The in vitro anticoagulant activity of the above mentioned peptides was determined using Wiener Lab Test (Wiener, Argentina). The toxicological activity of the peptides was also determined. The enzymatically synthesized Z-YQQ peptide acted on the extrinsic pathway of the coagulation cascade, delaying the conversion time of prothrombin to thrombin and fibrinogen to fibrin by 136% and 50%, respectively, with respect to the controls. The chemically synthesized YQQ peptide acted specifically on the intrinsic pathway of the coagulation cascade, affecting factors VIII, IX, XI and XII from such cascade, and increasing the coagulation time by 105% with respect to the control. The results suggest that two new anticoagulant peptides (Z-YQQ and YQQ) can be useful for safe pharmaceutical applications. Nevertheless, some aspects related to peptide production should be optimized. This article is protected by copyright. All rights reserved. © 2018 American Institute of Chemical Engineers.

Targeted inversion and reversion of the blood coagulation factor 8 gene in human iPS cells using TALENs.

PubMed

Park, Chul-Yong; Kim, Jungeun; Kweon, Jiyeon; Son, Jeong Sang; Lee, Jae Souk; Yoo, Jeong-Eun; Cho, Sung-Rae; Kim, Jong-Hoon; Kim, Jin-Soo; Kim, Dong-Wook

2014-06-24

Hemophilia A, one of the most common genetic bleeding disorders, is caused by various mutations in the blood coagulation factor VIII (F8) gene. Among the genotypes that result in hemophilia A, two different types of chromosomal inversions that involve a portion of the F8 gene are most frequent, accounting for almost half of all severe hemophilia A cases. In this study, we used a transcription activator-like effector nuclease (TALEN) pair to invert a 140-kbp chromosomal segment that spans the portion of the F8 gene in human induced pluripotent stem cells (iPSCs) to create a hemophilia A model cell line. In addition, we reverted the inverted segment back to its normal orientation in the hemophilia model iPSCs using the same TALEN pair. Importantly, we detected the F8 mRNA in cells derived from the reverted iPSCs lines, but not in those derived from the clones with the inverted segment. Thus, we showed that TALENs can be used both for creating disease models associated with chromosomal rearrangements in iPSCs and for correcting genetic defects caused by chromosomal inversions. This strategy provides an iPSC-based novel therapeutic option for the treatment of hemophilia A and other genetic diseases caused by chromosomal inversions.

Factor VIII inhibitor in a patient with mild haemophilia A and an Asn618-->Ser mutation responsive to immune tolerance induction and cyclophosphamide.

PubMed

Vlot, André J; Wittebol, Shulamiet; Strengers, Paul F W; Turenhout, Ellen A M; Voorberg, Jan; van den Berg, H Marijke; Mauser-Bunschoten, Eveline P

2002-04-01

We describe a patient with mild haemophilia A (original value of factor VIII activity 0.30 U/ml) who developed an inhibitor (36.1 Bethesda U/ml) which cross-reacted with his endogenous factor VIII. This caused a decline in basal factor VIII level (< 0.01 U/ml) and severe haemorrhagic events. Treatment to induce immune tolerance was started with factor VIII/von Willebrand factor (VWF) concentrates, but inhibitor levels increased progressively and the patient suffered serious bleeding. Cyclophosphamide was administered and, after 8 months treatment, factor VIII levels increased to 0.20 U/ml and the inhibitor could no longer be detected. Screening of his factor VIII gene revealed a missense mutation in exon 13 that predicts substitution of Asn618-->Ser in the A2 domain of factor VIII. Immunoprecipitation analysis showed that the antibodies present in the patient's plasma reacted with metabolically labelled A2 domain and, to a lesser extent, with factor VIII light chain. Inhibitory antibodies were completely neutralized by recombinant A2 domain, whereas no neutralization was observed after the addition of factor VIII light chain (A3-C1-C2) and C2 domain. More detailed analysis showed that the majority of inhibitory antibodies were directed against residues Arg484-Ile508, a previously identified binding site for factor VIII inhibitors. Our findings suggest that immune tolerance therapy and cyclophosphamide were successful in eradicating inhibitory antibodies against a common epitope on factor VIII.

Determinants of impaired renal and vascular function are associated with elevated levels of procoagulant factors in the general population.

PubMed

Dekkers, I A; de Mutsert, R; de Vries, A P J; Rosendaal, F R; Cannegieter, S C; Jukema, J W; le Cessie, S; Rabelink, T J; Lamb, H J; Lijfering, W M

2018-03-01

Essentials Why venous thrombosis is more prevalent in chronic kidney disease is unclear. We investigated whether renal and vascular function are associated with hypercoagulability. Coagulation factors showed a procoagulant shift with impaired renal and vascular function. This suggests that renal and vascular function play a role in the etiology of thrombosis. Background Impaired renal and vascular function have been associated with venous thrombosis, but the mechanism is unclear. Objectives We investigated whether estimated glomerular filtration rate (eGFR), urinary albumin-creatinine ratio (UACR), and pulse wave velocity (PWV) are associated with a procoagulant state. Methods In this cross-sectional analysis of the NEO Study, eGFR, UACR, fibrinogen, and coagulation factors (F)VIII, FIX and FXI were determined in all participants (n = 6536), and PWV was assessed in a random subset (n = 2433). eGFR, UACR and PWV were analyzed continuously and per percentile: per six categories for eGFR (> 50 th [reference] to < 1st) and UACR (< 50 th [reference] to > 99th), and per four categories (< 50 th [reference] to > 95th percentile) for PWV. Linear regression was used and adjusted for age, sex, total body fat, smoking, education, ethnicity, total cholesterol, C-reactive protein (CRP) and vitamin K antagonists use (FIX). Results Mean age was 55.6 years, mean eGFR 86.0 (12SD) mL 1.73 m - ² and median UACR 0.4 mg mmol -1 (25th, 75th percentile; 0.3, 0.7). All coagulation factors showed a procoagulant shift with lower renal function and albuminuria. For example, FVIII was 22 IU dL -1 (95% CI, 13-32) higher in the eGFR < 1st percentile compared with the > 50th percentile, and FVIII was 12 IU dL -1 (95% CI, 3-22) higher in the UACR > 99th percentile compared with the < 50th percentile. PWV was positively associated with coagulation factors FIX and FXI in continuous analysis; per m/s difference in PWV, FIX was 2.0 IU dL -1 (95% CI, 0.70-3.2) higher. Conclusions Impaired renal and vascular function was associated with higher levels of coagulation factors, underlining the role of renal function and vascular function in the development of venous thrombosis. © 2017 International Society on Thrombosis and Haemostasis.

Ischemic Stroke Is Associated with the ABO Locus: The EuroCLOT Study

PubMed Central

Williams, Frances M K; Carter, Angela M; Hysi, Pirro G; Surdulescu, Gabriela; Hodgkiss, Dylan; Soranzo, Nicole; Traylor, Matthew; Bevan, Steve; Dichgans, Martin; Rothwell, Peter M W; Sudlow, Cathie; Farrall, Martin; Silander, Kaisa; Kaunisto, Mari; Wagner, Peter; Saarela, Olli; Kuulasmaa, Kari; Virtamo, Jarmo; Salomaa, Veikko; Amouyel, Philippe; Arveiler, Dominique; Ferrieres, Jean; Wiklund, Per-Gunnar; Arfan Ikram, M; Hofman, Albert; Boncoraglio, Giorgio B; Parati, Eugenio A; Helgadottir, Anna; Gretarsdottir, Solveig; Thorsteinsdottir, Unnur; Thorleifsson, Gudmar; Stefansson, Kari; Seshadri, Sudha; DeStefano, Anita; Gschwendtner, Andreas; Psaty, Bruce; Longstreth, Will; Mitchell, Braxton D; Cheng, Yu-Ching; Clarke, Robert; Ferrario, Marco; Bis, Joshua C; Levi, Christopher; Attia, John; Holliday, Elizabeth G; Scott, Rodney J; Fornage, Myriam; Sharma, Pankaj; Furie, Karen L; Rosand, Jonathan; Nalls, Mike; Meschia, James; Mosely, Thomas H; Evans, Alun; Palotie, Aarno; Markus, Hugh S; Grant, Peter J; Spector, Tim D

2013-01-01

Objective End-stage coagulation and the structure/function of fibrin are implicated in the pathogenesis of ischemic stroke. We explored whether genetic variants associated with end-stage coagulation in healthy REFVIDunteers account for the genetic predisposition to ischemic stroke and examined their influence on stroke subtype. Methods Common genetic variants identified through genome-wide association studies of coagulation factors and fibrin structure/function in healthy twins (n = 2,100, Stage 1) were examined in ischemic stroke (n = 4,200 cases) using 2 independent samples of European ancestry (Stage 2). A third clinical collection having stroke subtyping (total 8,900 cases, 55,000 controls) was used for replication (Stage 3). Results Stage 1 identified 524 single nucleotide polymorphisms (SNPs) from 23 linkage disequilibrium blocks having significant association (p < 5 × 10–8) with 1 or more coagulation/fibrin phenotypes. The most striking associations included SNP rs5985 with factor XIII activity (p = 2.6 × 10–186), rs10665 with FVII (p = 2.4 × 10–47), and rs505922 in the ABO gene with both von Willebrand factor (p = 4.7 × 10–57) and factor VIII (p = 1.2 × 10–36). In Stage 2, the 23 independent SNPs were examined in stroke cases/noncases using MOnica Risk, Genetics, Archiving and Monograph (MORGAM) and Wellcome Trust Case Control Consortium 2 collections. SNP rs505922 was nominally associated with ischemic stroke (odds ratio = 0.94, 95% confidence interval = 0.88–0.99, p = 0.023). Independent replication in Meta-Stroke confirmed the rs505922 association with stroke, beta (standard error, SE) = 0.066 (0.02), p = 0.001, a finding specific to large-vessel and cardioembolic stroke (p = 0.001 and p = < 0.001, respectively) but not seen with small-vessel stroke (p = 0.811). Interpretation ABO gene variants are associated with large-vessel and cardioembolic stroke but not small-vessel disease. This work sheds light on the different pathogenic mechanisms underpinning stroke subtype. Ann Neurol 2013 PMID:23381943

Factor VIII organisation on nanodiscs with different lipid composition.

PubMed

Grushin, Kirill; Miller, Jaimy; Dalm, Daniela; Stoilova-McPhie, Svetla

2015-04-01

Nanodiscs (ND) are lipid bilayer membrane patches held by amphiphilic scaffolding proteins (MSP) of ~10 nm in diameter. Nanodiscs have been developed as lipid nanoplatforms for structural and functional studies of membrane and membrane associated proteins. Their size and monodispersity have rendered them unique for electron microscopy (EM) and single particle analysis studies of proteins and complexes either spanning or associated to the ND membrane. Binding of blood coagulation factors and complexes, such as the Factor VIII (FVIII) and the Factor VIIIa - Factor IXa (intrinsic tenase) complex to the negatively charged activated platelet membrane is required for normal haemostasis. In this study we present our work on optimising ND, specifically designed to bind FVIII at close to physiological conditions. The binding of FVIII to the negatively charged ND rich in phosphatidylserine (PS) was followed by electron microscopy at three different PS compositions and two different membrane scaffolding protein (MSP1D1) to lipid ratios. Our results show that the ND with highest PS content (80 %) and lowest MSP1D1 to lipid ratio (1:47) are the most suitable for structure determination of the membrane-bound FVIII by single particle EM. Our preliminary FVIII 3D reconstruction as bound to PS containing ND demonstrates the suitability of the optimised ND for structural studies by EM. Further assembly of the activated FVIII form (FVIIIa) and the whole FVIIIa-FIXa complex on ND, followed by EM and single particle reconstruction will help to identify the protein-protein and protein-membrane interfaces critical for the intrinsic tenase complex assembly and function.

Recombinant activated factor VII: 30 years of research and innovation.

PubMed

Hedner, Ulla

2015-06-01

Recombinant activated factor VII (rFVIIa) was initially developed to treat bleeding episodes in patients with congenital haemophilia and inhibitors. The story of its development began in the 1970s, when FVIIa was identified as one of the activated coagulation factors that has minimal potential for inducing thromboembolic side-effects. Extensive research over the last 30 years has greatly increased our knowledge of the characteristics of FVII, its activation, and the mechanisms by which rFVIIa restores haemostasis. In haemophilia, the haemostatic effect of rFVIIa is mediated via binding to thrombin-activated platelets at the site of injury, thereby enhancing thrombin generation also in the absence of factor (F) VIII or FIX. The mechanism of action of rFVIIa has also allowed its successful use in other clinical scenarios characterised by impaired thrombin generation, and its licensed uses have now been extended to acquired haemophilia, congenital FVII deficiency and Glanzmann's thrombasthenia. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effect of hyperthyroidism on procoagulant, anticoagulant and fibrinolytic factors: a systematic review and meta-analysis.

PubMed

Stuijver, Danka J F; van Zaane, Bregje; Romualdi, Erica; Brandjes, Dees P M; Gerdes, Victor E A; Squizzato, Alessandro

2012-12-01

Several coagulation and fibrinolytic parameters appear to be affected by thyroid hormone excess; however, the net effect on the haemostatic system remains unclear. We aimed to update our previous review and systematically summarise and meta-analyse the data by assessing the effects of thyrotoxicosis on the coagulation and fibrinolytic system in vivo . Data sources included MEDLINE (2006-2012), EMBASE (2006-2012), and reference lists. The sources were combined with our previous search containing studies from 1980-2006. Eligible studies were all observational or experimental studies. Two investigators independently extracted data and rated study quality. Weighted mean proportion and 95% confidence intervals were calculated and pooled using a fixed and a random-effects model. A total of 29 articles consisting of 51 studies were included, as in several articles more than one study was described. We included four intervention (before and after treatment in hyperthyroid patients), five cross-sectional (hyperthyroid subjects and euthyroid controls), and four experimental (before and after use of thyroid hormone in euthyroid subjects) medium/high quality studies for meta-analysis. We found that thyrotoxicosis shifts the haemostatic balance towards a hypercoagulable and hypofibrinolytic state with a rise in factors VIII and IX, fibrinogen, von Willebrand factor, and plasminogen activator inhibitor-1. This was observed in endogenous and exogenous thyrotoxicosis, and in subclinical as well as overt hyperthyroidism. We conclude that both subclinical and overt hyperthyroidism induce a prothrombotic state, which is therefore likely to be a risk factor for venous thrombosis.

Clinical and laboratory diagnosis of von Willebrand disease: A synopsis of the 2008 NHLBI/NIH guidelines

PubMed Central

Nichols, William L.; Rick, Margaret E.; Ortel, Thomas L.; Montgomery, Robert R.; Sadler, J. Evan; Yawn, Barbara P.; James, Andra H.; Hultin, Mae B.; Manco-Johnson, Marilyn J.; Weinstein, Mark

2017-01-01

Von Willebrand factor (VWF) mediates blood platelet adhesion and accumulation at sites of blood vessel injury, and also carries coagulation factor VIII (FVIII) that is important for generating procoagulant activity. Von Willebrand disease (VWD), the most common inherited bleeding disorder, affects males and females, and reflects deficiency or defects of VWF that may also cause decreased FVIII. It may also occur less commonly as an acquired disorder (acquired von Willebrand syndrome). This article briefly summarizes selected features of the March 2008 evidence-based clinical and laboratory diagnostic recommendations from the National Heart, Lung, and Blood Institute (NHLBI) Expert Panel for assessment for VWD or other bleeding disorders or risks. Management of VWD is also addressed in the NHLBI guidelines, but is not summarized here. The VWD guidelines are available at the NHLBI Web site (http://www.nhlbi.nih.gov/guidelines/vwd). PMID:19415721

Transient transfection of serum-free suspension HEK 293 cell culture for efficient production of human rFVIII.

PubMed

Swiech, Kamilla; Kamen, Amine; Ansorge, Sven; Durocher, Yves; Picanço-Castro, Virgínia; Russo-Carbolante, Elisa M S; Neto, Mário S A; Covas, Dimas T

2011-11-24

Hemophilia A is a bleeding disorder caused by deficiency in coagulation factor VIII. Recombinant factor VIII (rFVIII) is an alternative to plasma-derived FVIII for the treatment of hemophilia A. However, commercial manufacturing of rFVIII products is inefficient and costly and is associated to high prices and product shortage, even in economically privileged countries. This situation may be solved by adopting more efficient production methods. Here, we evaluated the potential of transient transfection in producing rFVIII in serum-free suspension HEK 293 cell cultures and investigated the effects of different DNA concentration (0.4, 0.6 and 0.8 μg/106 cells) and repeated transfections done at 34° and 37 °C. We observed a decrease in cell growth when high DNA concentrations were used, but no significant differences in transfection efficiency and in the biological activity of the rFVIII were noticed. The best condition for rFVIII production was obtained with repeated transfections at 34 °C using 0.4 μg DNA/106 cells through which almost 50 IU of active rFVIII was produced six days post-transfection. Serum-free suspension transient transfection is thus a viable option for high-yield-rFVIII production. Work is in progress to further optimize the process and validate its scalability.

The Chapel Hill hemophilia A dog colony exhibits a factor VIII gene inversion

PubMed Central

Lozier, Jay N.; Dutra, Amalia; Pak, Evgenia; Zhou, Nan; Zheng, Zhili; Nichols, Timothy C.; Bellinger, Dwight A.; Read, Marjorie; Morgan, Richard A.

2002-01-01

In the Chapel Hill colony of factor VIII-deficient dogs, abnormal sequence (ch8, for canine hemophilia 8, GenBank no. AF361485) follows exons 1–22 in the factor VIII transcript in place of exons 23–26. The canine hemophilia 8 locus (ch8) sequence was found in a 140-kb normal dog genomic DNA bacterial artificial chromosome (BAC) clone that was completely outside the factor VIII gene, but not in BAC clones containing the factor VIII gene. The BAC clone that contained ch8 also contained a homologue of F8A (factor 8 associated) sequence, which participates in a common inversion that causes severe hemophilia A in humans. Fluorescence in situ hybridization analysis indicated that exons 1–26 normally proceed sequentially from telomere to centromere at Xq28, and ch8 is telomeric to the factor VIII gene. The appearance of an “upstream” genomic sequence element (ch8) at the end of the aberrant factor VIII transcript suggested that an inversion of genomic DNA replaced factor VIII exons 22–26 with ch8. The F8A sequence appeared also in overlapping normal BAC clones containing factor VIII sequence. We hypothesized that homologous recombination between copies of canine F8A inside and outside the factor VIII gene had occurred, as in human hemophilia A. High-resolution fluorescent in situ hybridization on hemophilia A dog DNA revealed a pattern consistent with this inversion mechanism. We also identified a HindIII restriction fragment length polymorphism of F8A fragments that distinguished hemophilia A, carrier, and normal dogs' DNA. The Chapel Hill hemophilia A dog colony therefore replicates the factor VIII gene inversion commonly seen in humans with severe hemophilia A. PMID:12242334

Thermodynamic analysis of the interaction of factor VIII with von Willebrand factor.

PubMed

Dimitrov, Jordan D; Christophe, Olivier D; Kang, Jonghoon; Repessé, Yohann; Delignat, Sandrine; Kaveri, Srinivas V; Lacroix-Desmazes, Sébastien

2012-05-22

Factor VIII (FVIII) is a glycoprotein that plays an important role in the intrinsic pathway of coagulation. In circulation, FVIII is protected upon binding to von Willebrand factor (VWF), a chaperone molecule that regulates its half-life, distribution, and activity. Despite the biological significance of this interaction, its molecular mechanisms are not fully characterized. We determined the equilibrium and activation thermodynamics of the interaction between FVIII and VWF. The equilibrium affinity determined by surface plasmon resonance was temperature-dependent with a value of 0.8 nM at 35 °C. The FVIII-VWF interaction was characterized by very fast association (8.56 × 10(6) M(-1) s(-1)) and fast dissociation (6.89 × 10(-3) s(-1)) rates. Both the equilibrium association and association rate constants, but not the dissociation rate constant, were dependent on temperature. Binding of FVIII to VWF was characterized by favorable changes in the equilibrium and activation entropy (TΔS° = 89.4 kJ/mol, and -TΔS(++) = -8.9 kJ/mol) and unfavorable changes in the equilibrium and activation enthalpy (ΔH° = 39.1 kJ/mol, and ΔH(++) = 44.1 kJ/mol), yielding a negative change in the equilibrium Gibbs energy. Binding of FVIII to VWF in solid-phase assays demonstrated a high sensitivity to acidic pH and a sensitivity to ionic strength. Our data indicate that the interaction between FVIII and VWF is mediated mainly by electrostatic forces, and that it is not accompanied by entropic constraints, suggesting the absence of conformational adaptation but the presence of rigid "pre-optimized" binding surfaces.

Analysis of contaminants in factor VIII preparations administered to patients with hemophilia.

PubMed Central

Rock, G. A.; Farrah, G.; Rozon, G.; Smiley, R. K.; Cole, R.; Villeneuve, D.; Tittley, P.

1983-01-01

Cryoprecipitate and the more purified factor VIII concentrates are all heterogeneous preparations that contain not only a high concentration of factor VIII but also various other materials, some of which might be injurious, causing liver damage after long-term exposure. The efficiency of three standard cryoprecipitate filters, two microaggregate filters and the appropriate factor VIII concentrate filters in reducing the amount of particulate matter delivered to the patient was assessed. Filtration of cryoprecipitate through the standard filters removed less than 20% of the contaminating microaggregates and very few of the large number of intact platelets, although the total dose of factor VIII was delivered. Microaggregate filters were no better in reducing the platelet contamination, although the total number of particles delivered was halved. However, 25% of the factor VIII was retained in the bed volume of the filter. The concentrate preparations also contained significant amounts of particulate matter that was unrelated to factor VIII and was not removed following filtration through the designated filter. These findings indicate that a new filter should be developed for administration of factor VIII concentrate that would remove the particulate matter while delivering all of the factor VIII to the patient. Images FIG. 1 FIG. 2 FIG. 3 FIG. 5 PMID:6401585

Moderate-intensity exercise improves the thromboelastography coagulation index in children with severe hemophilia A.

PubMed

Li, Kui-Xing; Xiao, Juan; Zhao, Yong-Qiang; Shou, Wei-Ling; Chen, Meng; Li, Zhuo; Poon, Man-Chiu; Han, Hui-Jun

2016-10-01

This pilot study explored the effect of moderate-intensity exercise on factor VIII (FVIII) activity and global hemostatic status of the children with severe hemophilia A. Eleven children aged 6 to 15 years with severe hemophilia A participated in a moderate-intensity exercise test by using Recumbent Cross Trainer (NuStep, T5XR) for at least 10 min after reaching the target heart rate or until volitional exhaustion within a safety framework. Blood samples were collected pre and postexercise for plasma FVIII: C and thromboelastography (TEG) parameters and coagulation index. The average duration of exercise was 11.8 min (10-13 min). There was no report on bleeding events or adverse symptoms requiring termination of the exercise test. The average FVIII activity of the 11 children was 0.66 (0.5-0.8) IU/dl before and 0.93 (0.5-2.3) IU/dl after exercise. The increase of FVIII in the 11 children as a group was not statistically significant (P = 0.052). There were significant changes of TEG measurements, with shortening of R (P < 0.05), and increase in K decrease (P < 0.05), alpha angle (P < 0.05), maximum amplitude (P < 0.05), and coagulation index (P < 0.01). Among the 11 children, the relative coagulation index increase after exercise was greater than 50% in seven (63.6%), less than 20% in three (27.3%), and less than 10% in one (9.1%). TEG analysis showed that the global hemostatic function for the children with severe hemophilia A can be enhanced after moderate-intensity exercise.

Global measurement of coagulation in plasma from normal and haemophilia dogs using a novel modified thrombin generation test – Demonstrated in vitro and ex vivo

PubMed Central

Madsen, Daniel Elenius; Nichols, Timothy C.; Merricks, Elizabeth P.; Waters, Emily K.; Wiinberg, Bo

2017-01-01

Introduction Canine models of severe haemophilia resemble their human equivalents both regarding clinical bleeding phenotype and response to treatment. Therefore pre-clinical studies in haemophilia dogs have allowed researchers to make valuable translational predictions regarding the potency and efficacy of new anti-haemophilia drugs (AHDs) in humans. To refine in vivo experiments and reduce number of animals, such translational studies are ideally preceded by in vitro prediction of compound efficacy using a plasma based global coagulation method. One such widely used method is the thrombin generation test (TGT). Unfortunately, commercially available TGTs are incapable of distinguishing between normal and haemophilia canine plasma, and therefore in vitro prediction using TGT has so far not been possible in canine plasma material. Aim Establish a modified TGT capable of: 1) distinguishing between normal and haemophilia canine plasma, 2) monitoring correlation between canine plasma levels of coagulation factor VIII (FVIII) and IX (FIX) and thrombin generation, 3) assessing for agreement between compound activity and thrombin generation in ex vivo samples. Methods A modified TGT assay was established where coagulation was triggered using a commercially available activated partial thromboplastin time reagent. Results With the modified TGT a significant difference was observed in thrombin generation between normal and haemophilia canine plasma. A dose dependent thrombin generation was observed when assessing haemophilia A and B plasma spiked with dilution series of FVIII and FIX, respectively. Correlation between FVIII activity and thrombin generation was observed when analyzing samples from haemophilia A dogs dosed with canine FVIII. Limit of detection was 0.1% (v/v) FVIII or FIX. Conclusion A novel modified TGT suitable for monitoring and prediction of replacement therapy efficacy in plasma from haemophilia A and B dogs was established. PMID:28384182

Investigation of inflicted injury in a young girl reveals mild haemophilia A and Turner's syndrome.

PubMed

Williams, V K; Suppiah, R; Coppin, B; Nicholls, C M; Simsek, A; McGregor, L K

2012-02-01

A 2-year-old girl presented to casualty with a right knee effusion after apparently minor trauma. Inflicted injury was suspected and full forensic coagulation studies were performed which revealed a mild deficiency of factor VIII. Screening of the exons and intron/exon boundaries of F8 gene indicated that the child appeared to be homozygous for the missense mutation c.5123G>A (p.Arg1708His) in exon 14 of the F8 gene. This mutation has been reported to be associated with mild haemophilia A. The possibility of hemizygosity had been masked by the test kit employed but referral to the genetics service and subsequent array CGH resulted in a diagnosis of Turner syndrome. © 2011 Blackwell Publishing Ltd.

The role of recombinant activated factor VII in neurosurgery: hope or hype?

PubMed

Hawryluk, Gregory W J; Cusimano, Michael D

2006-12-01

Recombinant activated factor VII (rFVIIa) is a relatively new pharmaceutical agent developed for use in patients with hemophilia in whom inhibitors to clotting factors VIII or IX have developed. Use of this drug has become common in recent years because of its efficacy and safety in patients with coagulation disorders as well as in patients who are at high risk for thromboembolism, even when other means of establishing hemostasis have failed. The use of rFVIIa in neurosurgery has lagged behind its use in other fields, although there is a growing body of literature on such uses. In this article the authors review the history and science of rFVIIa as well as dosing and safety information. Various uses pertinent to the neurosurgeon are reviewed, including the treatment of patients with coagulation disorders, those suffering trauma, and those with perioperative hemorrhage, intracerebral hemorrhage, or subarachnoid hemorrhage. Based on their review of the uses of rFVIIa, the authors conclude that rFVIIa is a safe and effective agent with the potential to revolutionize the treatment of neurosurgical patients with hemorrhage. Cost is a major impediment to the widespread use of rFVIIa, and there is some evidence that its use in the neurosurgical population may be subject to higher risk than in other populations studied thus far. Although further study is needed to better delineate the safety and efficacy of the drug in many nonlicensed uses, it is clear that rFVIIa is an agent with tremendous promise.

[Long distance-PCR for detection of factor VIII gene inversion in patients with severe hemophilia A].

PubMed

Ding, Pei-Fang; Sun, Wei-Sheng; Wang, Qin-You; Liu, De-Chun; Zhang, Xue-Qin; Teng, Bin; Shen, Fa-Kui

2003-08-01

The aim of current study was to detect intron 22 inversion of factor VIII gene in severe hemophilia A (HA) patients and screen the carriers of the gene inversion. Fifty-five cases of severe HA were involved and factor VIII gene inversion was detected and identified by long distance-PCR (LD-PCR) and 0.6% agarose gel electrophoresis. The 11 kb and 12 kb bands indicate the factor VIII gene inversion and non-inversion, respectively. Occurring of both 11 kb and 12 kb bands indicates a carrier of the inversion. The results showed that factor VIII gene inversion existed in 22 out of 55 cases, which accounted for about 40% of total detected patients. Five carriers of factor VIII gene inversion were diagnosed from the members in 15 families. In conclusion, LD-PCR assay is a simple, rapid and accurate method for detection of factor VIII gene inversion, and this approach is helpful in screening, carrier testing, and prenatal diagnosis of severe hemophilia A.

Gene Delivery of Activated Factor VII Using Alternative Adeno-Associated Virus Serotype Improves Hemostasis in Hemophiliac Mice with FVIII Inhibitors and Adeno-Associated Virus Neutralizing Antibodies.

PubMed

Sun, Junjiang; Hua, Baolai; Chen, Xiaojing; Samulski, Richard J; Li, Chengwen

2017-08-01

While therapeutic expression of coagulation factors from adeno-associated virus (AAV) vectors has been successfully achieved in patients with hemophilia, neutralizing antibodies to the vector and inhibitory antibodies to the transgene severely limit efficacy. Indeed, approximately 40% of mice transduced with human factor VIII using the AAV8 serotype developed inhibitory antibodies to factor VIII (FVIII inhibitor), as well as extremely high titers (≥1:500) of neutralizing antibodies to AAV8. To correct hemophilia in these mice, AAV9, a serotype with low in vitro cross-reactivity (≤1:5) to anti-AAV8, was used to deliver mouse-activated factor VII (mFVIIa). It was found that within 6 weeks of systemic administration of 2 × 10 13 particles/kg of AAV9/mFVIIa, hemophiliac mice with FVIII inhibitors and neutralizing antibodies (NAb) to AAV8 achieved hemostasis comparable to that in wild-type mice, as measured by rotational thromboelastometry. A level of 737 ng/mL mFVIIa was achieved after AAV9/mFVIIa adminstration compared to around 150 ng/mL without vector treatment, and concomitantly prothrombin time was shortened. Tissues collected after intra-articular hemorrhage from FVIII-deficient mice and mice with FVIII inhibitors were scored 4.7 and 5.5, respectively, on a scale of 0-10, indicating significant pathological damage. However, transduction with AAV9/mFVIIa decreased pathology scores to 3.6 and eliminated hemosiderin iron deposition in the synovium in most mice. Collectively, these results suggest that application of alternative serotypes of AAV vector to deliver bypassing reagents has the potential to correct hemophilia and prevent hemoarthrosis, even in the presence of FVIII inhibitor and neutralizing antibodies to AAV.

Association of ABO blood groups with von Willebrand factor, factor VIII and ADAMTS-13 in patients with lung cancer.

PubMed

Liu, Xia; Chen, Xiaogang; Yang, Jiezuan; Guo, Renyong

2017-09-01

Coagulative and fibrinolytic disorders appear to be associated with the development of lung cancer. The aim of the present study was to determine plasma levels of von Willebrand factor (VWF) and a disintegrin and metalloproteinase with a thrombospondin type 1 motif 13 (ADAMTS-13), and factor VIII (FVIII) activity, in association with O and non-O blood groups in patients with lung cancer. Plasma levels of VWF and ADAMTS-13, and FVIII activity were measured in 115 patients with lung cancer and 98 healthy subjects. Phenotyping of the ABO blood groups was also performed for the two groups. Significantly increased VWF levels and FVIII activity, as well as significantly decreased ADAMTS-13 levels, were observed in patients with distant metastasis as compared with those without distant metastasis and the healthy controls. Plasma VWF levels and FVIII activity were significantly increased in subjects with non-O type blood compared with those with type O blood in the two groups. However, a significant decrease in ADAMTS-13 levels was observed only in the control group among those with non-O type blood, compared with those with type O blood. The results of the present study indicate that increased VWF and decreased ADAMTS-13 levels facilitate the invasiveness and metastasis of lung cancer. Non-O blood groups constitute a risk factor for increased VWF and FVIII in plasma. Continued monitoring of VWF and ADAMTS-13 levels, and of FVIII activity in patients with lung cancer with distinct blood groups may help to minimize the incidence of thrombotic events and improve assessment of disease progression.

Platelet binding sites for factor VIII in relation to fibrin and phosphatidylserine

PubMed Central

Novakovic, Valerie A.; Shi, Jialan; Rasmussen, Jan; Pipe, Steven W.

2015-01-01

Thrombin-stimulated platelets expose very little phosphatidylserine (PS) but express binding sites for factor VIII (fVIII), casting doubt on the role of exposed PS as the determinant of binding sites. We previously reported that fVIII binding sites are increased three- to sixfold when soluble fibrin (SF) binds the αIIbβ3 integrin. This study focuses on the hypothesis that platelet-bound SF is the major source of fVIII binding sites. Less than 10% of fVIII was displaced from thrombin-stimulated platelets by lactadherin, a PS-binding protein, and an fVIII mutant defective in PS-dependent binding retained platelet affinity. Therefore, PS is not the determinant of most binding sites. FVIII bound immobilized SF and paralleled platelet binding in affinity, dependence on separation from von Willebrand factor, and mediation by the C2 domain. SF also enhanced activity of fVIII in the factor Xase complex by two- to fourfold. Monoclonal antibody (mAb) ESH8, against the fVIII C2 domain, inhibited binding of fVIII to SF and platelets but not to PS-containing vesicles. Similarly, mAb ESH4 against the C2 domain, inhibited >90% of platelet-dependent fVIII activity vs 35% of vesicle-supported activity. These results imply that platelet-bound SF is a component of functional fVIII binding sites. PMID:26162408

Hepatitis C treatment with triple therapy in a patient with hemophilia A

PubMed Central

Singh, Gurshawn; Sass, Reuben; Alamiry, Rayan; Zein, Nizar; Alkhouri, Naim

2013-01-01

We report a case of successful treatment of chronic hepatitis C infection with telaprevir-based triple therapy in a patient with hemophilia A complicated by factor VIII inhibitor. A twenty-two years old male with hereditary hemophilia A and high-titer factor VIII inhibitor was taking maintenance doses of recombinant factor VIII. He visited our clinic for treatment of his chronic hepatitis C with the newly instituted protease inhibitor based therapy. He was diagnosed with hepatitis C genotype 1a at one year of age. He was initiated on telaprevir, ribavirin and peg-interferon for treatment of hepatitis C and qualified for response-guided therapy. He completed treatment at 24 wk with minimal adverse effects. Notably, after 4 wk of hepatitis C treatment, his factor VIII inhibitor screen was negative and the dose for recombinant factor VIII decreased by half of the initial dosing before he was treated for hepatitis C. We suspect that suppressing hepatitis C may help decrease factor VIII inhibitor level and the need for recombinant factor VIII. PMID:24303477

Preanalytical influence of pneumatic tube delivery system on results of routine biochemistry and haematology analysis.

PubMed

Petit, Morgane; Mine, Louis; Pascreau, Tiffany; Brouzes, Chantal; Majoux, Sandrine; Borgel, Delphine; Beaudeux, Jean-Louis; Lasne, Dominique; Hennequin, Carole

2017-12-01

Pneumatic tube delivery system (PTS) enables to reduce considerably turnaround times. The aim of the study was to assess the influence of the PTS on the quality of routine biochemical and hematological tests in our laboratory. Blood samples from 6 hospitalized patients and 8 healthy volunteers were analyzed. Blood samples were delivered to the laboratory by a PTS and by a human courier. We performed the following analysis: ionized calcium, sodium, potassium, lactate deshydrogenase (LDH), aspartate aminotransferase (ASAT), arterial blood gas, complete blood count and coagulation test as prothrombin time, activated partial thromboplastin time, factors V and VIII. Results were compared between the both method of transport according to the recommendation of the Société française de biologie clinique and the French committee for accreditation (SH-GTA01, norme NF ISO 5275-6). The hemolysis index of plasma was similar between the groups and no morphological differences were found on blood cells. For three samples, when delivered by PTS, LDH levels (two samples) and neutrophil polynuclear count (one sample) were above the recommended guidelines compared to those delivered by courier. Conversely, LDH levels and FVIII were below in two samples delivered by PTS. LDH levels, PNN count or factor VIII can be affected by PTS without the clinical interpretation being modified. We concluded that the PTS can be used to transport blood samples for routine biochemical and hematological analysis in our hospital.

Circumventing furin enhances factor VIII biological activity and ameliorates bleeding phenotypes in hemophilia models

PubMed Central

Siner, Joshua I.; Samelson-Jones, Benjamin J.; Crudele, Julie M.; French, Robert A.; Lee, Benjamin J.; Zhou, Shanzhen; Merricks, Elizabeth; Raymer, Robin; Camire, Rodney M.; Arruda, Valder R.

2016-01-01

Processing by the proprotein convertase furin is believed to be critical for the biological activity of multiple proteins involved in hemostasis, including coagulation factor VIII (FVIII). This belief prompted the retention of the furin recognition motif (amino acids 1645–1648) in the design of B-domain–deleted FVIII (FVIII-BDD) products in current clinical use and in the drug development pipeline, as well as in experimental FVIII gene therapy strategies. Here, we report that processing by furin is in fact deleterious to FVIII-BDD secretion and procoagulant activity. Inhibition of furin increases the secretion and decreases the intracellular retention of FVIII-BDD protein in mammalian cells. Our new variant (FVIII-ΔF), in which this recognition motif is removed, efficiently circumvents furin. FVIII-ΔF demonstrates increased recombinant protein yields, enhanced clotting activity, and higher circulating FVIII levels after adeno-associated viral vector–based liver gene therapy in a murine model of severe hemophilia A (HA) compared with FVIII-BDD. Moreover, we observed an amelioration of the bleeding phenotype in severe HA dogs with sustained therapeutic FVIII levels after FVIII-ΔF gene therapy at a lower vector dose than previously employed in this model. The immunogenicity of FVIII-ΔF did not differ from that of FVIII-BDD as a protein or a gene therapeutic. Thus, contrary to previous suppositions, FVIII variants that can avoid furin processing are likely to have enhanced translational potential for HA therapy. PMID:27734034

Dominant von Willebrand disease type 2A groups I and II due to missense mutations in the A2 domain of the von Willebrand factor gene: diagnosis and management.

PubMed

Michiels, Jan Jacques; van Vliet, Huub H D M

2009-01-01

Pertinent findings in patients with von Willebrand disease (VWD) type 2A include prolonged bleeding time (BT), consistently low von Willebrand factor (VWF):ristocetin cofactor activity (RCo)/antigen concentration (Ag) and VWF:collagen binding (CB)/Ag ratios, absence of high, and (depending on severity) intermediate and large VWF multimers, the presence of pronounced triplet structure of individual bands and increased VWF degradation products due to increased proteolysis caused by mutations in the A2 domain of VWF. Two categories of VWD type 2A can be distinguished: group I with severe and group II with mild VWD. A minority of VWD type 2A have mild VWD characterized by near normal to prolonged BT, normal factor VIII coagulant activity and VWF:Ag, low VWF:RCo and VWF:CB, a normal ristocetin-induced platelet aggregation and complete but transient correction of BT and functional VWF parameters to normal levels for only a few hours due to short half-lives for VWF:RCo and CWF:CB. Such transient complete responses to desmopressin (DDAVP) lasting only a few hours may facilitate treatment and prophylaxis of minor bleedings, but may not be able to prevent bleeding during minor and major surgery. Most VWD type 2A patients have pronounced VWD with very low VWF:RCo, prolonged BT, PFA-100 closure times >250 s, and response to DDAVP is only transient, minor, poor or absent, with no correction of the BT despite some increase in VWF:RCo, thus being candidates for factor VIII-VWF concentrate substitution for the acute and prophylactic treatment of bleeding symptoms. Copyright (c) 2009 S. Karger AG, Basel.

[Hypercoagulability during pregnancy: evidences for a thrombophilic state].

PubMed

Maiello, M; Torella, M; Caserta, L; Caserta, R; Sessa, M; Tagliaferri, A; Bernacchi, M; Napolitano, M; Nappo, C; De Lucia, D; Panariello, S

2006-10-01

The development of thrombotic disorders is a major threat for young women during pregnancy. It is one of the main causes of pregnancy-related disorders, which may also result in harm for the conceptus. Successful pregnancies require an even balance of coagulation and fibrinolysis, in order to secure stabilization of the basal plate as well as adequate placental perfusion. Broad spectrum assays which measure a range of thrombin/fibrin formation in serum have become an established means of identifying activation of blood coagulation and/or fibrinolysis. There is considerable interest in the application of these assays to the diagnosis of other hypercoagulable states, such as thrombophilia during pregnancy. We investigated coagulation/fibrinolysis parameters for significant differences between pregnant women during their gestation (first, second and third trimester) with or without pregnancy loss and healthy nonpregnant women. Thirty-nine pregnant women, aged 24-39 years, were studied. They were subdivided according to pregnancy trimester: 15 patients in the first trimester; 13 in the second and 11 in the third. The selection of patients was carried out in cooperation with the Transfusion Center of the Second University of Naples in order to obtain a homogeneous sample group. The control group included 400 healthy patients. Biochemical and blood coagulation tests were performed for each patient and the results obtained were compared with the control group. A decrease in free protein S (PS) and fibrinolysis (t-PA/PAI-1) activities and an increase in Factor VII, Factor VIII, prothrombin fragment 1+2 (F1+2), D-dimer (D-dimer) were observed in pregnant women during the follow-up of gestation. However, there were statistical differences between the groups of women with one or more pregnancy loss where it was found the lowest values in t-PA and PAI and the highest values in FVII and F1+2. Among subjects with more than one abortion, coagulation/fibrinolysis derangements before the partum were more prominent. A significant association exists between consecutive recurrent abortions and pregnancy complications such as placental abruption, hypertensive disorders and CS. This association persists after controlling for variables considered to coexist with recurrent abortions. These findings suggest that an excessive hypercoagulable state is associated with the termination of pregnancy resulting into a moderate risk for thrombosis during the different trimesters of pregnancy. The follow-up of fibrinolytic markers could represent a useful diagnostic tool for termination of pregnancy.

Gene Therapy for Hemophilia.

PubMed

Nienhuis, Arthur W; Nathwani, Amit C; Davidoff, Andrew M

2017-05-03

The X-linked bleeding disorder hemophilia causes frequent and exaggerated bleeding that can be life-threatening if untreated. Conventional therapy requires frequent intravenous infusions of the missing coagulation protein (factor VIII [FVIII] for hemophilia A and factor IX [FIX] for hemophilia B). However, a lasting cure through gene therapy has long been sought. After a series of successes in small and large animal models, this goal has finally been achieved in humans by in vivo gene transfer to the liver using adeno-associated viral (AAV) vectors. In fact, multiple recent clinical trials have shown therapeutic, and in some cases curative, expression. At the same time, cellular immune responses against the virus have emerged as an obstacle in humans, potentially resulting in loss of expression. Transient immune suppression protocols have been developed to blunt these responses. Here, we provide an overview of the clinical development of AAV gene transfer for hemophilia, as well as an outlook on future directions. Copyright © 2017. Published by Elsevier Inc.

[Plasma fractionation in the world: current status].

PubMed

Burnouf, T

2007-05-01

From 22 to 25 million liters of plasma are fractionated yearly in about 70 fractionation plants, either private or government-owned, mainly located in industrialized countries, and with a capacity ranging from 50000 to three million liters. In an increasingly global environment, the plasma industry has recently gone through a major consolidation phase that has seen mergers and acquisitions, and has led to the closure of a number of small plants in Europe. Currently, some fifteen countries are involved into contract plasma fractionation programs to ensure a supply of plasma-derived medicinal products. The majority of the plasma for fractionation is obtained by automated plasmapheresis, the remaining (recovered plasma) being prepared from whole blood as a by-product of red cell production. Plasma for fractionation should be produced, and controlled following well established procedures to meet the strict quality requirements set by regulatory authorities and fractionators. The plasma fractionation technology still relies heavily on the cold ethanol fractionation process, but has been improved by the introduction of modern chromatographic purification methods, and efficient viral inactivation and removal treatments, ensuring quality and safety to a large portfolio of fractionated plasma products. The safety of these products with regards to the risk of transmission of variant Creutzfeldt-Jakob disease seems to be provided, based on current scientific data, by extensive removal of the infectious agent during certain fractionation steps. The leading plasma product is now the intravenous immunoglobulin G, which has replaced factor VIII and albumin in this role. The supply of plasma products (most specifically coagulation products and immunoglobulin) at an affordable price and in sufficient quantity remains an issue; the problem is particularly acute in developing countries, as the switch to recombinant factor VIII in rich countries has not solved the supply issue and has even led to an increase of the mean price of plasma-derived factor VIII to the developing world. In the last few years, the plasma fractionation industry has improved greatly, and should remain essential in the years to come for the procurement of many essential medicines.

Pregnancy and delivery in women with von Willebrand's disease and different von Willebrand factor mutations.

PubMed

Castaman, Giancarlo; Tosetto, Alberto; Rodeghiero, Francesco

2010-06-01

Pregnancy in von Willebrand's disease may carry a significant risk of bleeding. Information on changes in factor VIII and von Willebrand factor and pregnancy outcome in relation to von Willebrand factor gene mutations are very scanty. We examined biological response to desmopressin, changes in factor VIII and von Willebrand factor and pregnancy outcome in a cohort of 23 women with von Willebrand's disease characterized at molecular level and prospectively followed during 2000-2007. Thirty-one pregnancies occurred during the study period. Remarkably, similar changes of factor VIII and von Willebrand factor were observed after desmopressin and during pregnancy in nine women with R854Q, R1374H, V1665E, V1822G and C2362F mutations. Women with von Willebrand's disease and R1205H and C1130F mutations (17 pregnancies in 12 women) had only a slight increase of factor VIII and von Willebrand factor during pregnancy while their response to desmopressin was marked but short-lived. For these women, two to three desmopressin administrations within the first 48 hours were sufficient to successfully manage vaginal delivery. Two women with recessive von Willebrand's disease due to compound heterozygosity for different gene mutations had a spontaneous, major increase in factor VIII while von Willebrand factor remained severely reduced. Desmopressin increased factor VIII and was clinically useful in the first case, while a factor VIII/von Willebrand factor concentrate was required in the second patient not responsive to the compound. Factor VIII/von Willebrand factor concentrate was also required for two women with type 2 A von Willebrand's disease with V1665E mutations who had no von Willebrand factor activity change during pregnancy. In one of them, delayed bleeding occurred 15 days later requiring treatment with Factor VIII/von Willebrand factor concentrate. No miscarriages or stillbirths occurred. Close follow-up and detailed guidelines for the management of parturition have produced a very low rate of immediate and late bleeding complications in this setting. Desmopressin was effective and safe in preventing significant bleeding at delivery in most of these patients.

Quantitative immunohistochemistry of factor VIII-related antigen in breast carcinoma: a comparison of computer-assisted image analysis with established counting methods.

PubMed

Kohlberger, P D; Obermair, A; Sliutz, G; Heinzl, H; Koelbl, H; Breitenecker, G; Gitsch, G; Kainz, C

1996-06-01

Microvessel density in the area of the most intense neovascularization in invasive breast carcinoma is reported to be an independent prognostic factor. The established method of enumeration of microvessel density is to count the vessels using an ocular raster (counted microvessel density [CMVD]). The vessels were detected by staining endothelial cells using Factor VIII-related antigen. The aim of the study was to compare the CMVD results with the percentage of factor VIII-related antigen-stained area using computer-assisted image analysis. A true color red-green-blue (RGB) image analyzer based on a morphologically reduced instruction set computer processor was used to evaluate the area of stained endothelial cells. Sixty invasive breast carcinomas were included in the analysis. There was no significant correlation between the CMVD and the percentage of factor VIII-related antigen-stained area (Spearman correlation coefficient = 0.24, confidence interval = 0.02-0.46). Although high CMVD was significantly correlated with poorer recurrence free survival (P = .024), percentage of factor VIII-related antigen-stained area showed no prognostic value. Counted microvessel density and percentage of factor VIII-related antigen-stained area showed a highly significant correlation with vessel invasion (P = .0001 and P = .02, respectively). There was no correlation between CMVD and percentage of factor VIII-related antigen-stained area with other prognostic factors. In contrast to the CMVD within malignant tissue, the percentage of factor VIII-related antigen-stained area is not suitable as an indicator of prognosis in breast cancer patients.

[Concepts in anticoagulant therapy - past, present, and future].

PubMed

Graf, L

2012-11-01

The understanding of the clotting system emerged in parallel to the development of anticoagulants. In contrast to vitamin K-antagonists and heparins that where discovered by chance, new anticoagulants have been systematically designed to specifically inhibit single clotting factors. Both clotting factors Xa (FXa) and thrombin play a crucial role within the new cell-based model of hemostasis. Thus it is obvious that FXa and thrombin turned out to be ideal targets for anticoagulation. The proof of the concept of selective inhibition of thrombin and FXa has been provided by hirudin and fondaparinux, respectively. By now, a whole group of new oral anticoagulants has been licensed: the direct FXa-inhibitors rivaroxaban, apixaban, and edoxaban as well as the direct thrombin dabigatran etexilate. Furthermore, a bundle of FXa- and thrombin-inhibitors that differ from the so far licensed products mainly in pharmacokinetics are in an advanced phase of development. A further innovative concept of anticoagulation that entered its clinical phase of development is the inhibition of factor VIII. Other new concepts such as inhibition of initiation of coagulation by blocking factor VIIa, inhibition of contact factor XII, or inhibition of factor IX are in an early phase of development.

Incidence and risk factors of bleeding-related adverse events in patients with chronic lymphocytic leukemia treated with ibrutinib.

PubMed

Lipsky, Andrew H; Farooqui, Mohammed Z H; Tian, Xin; Martyr, Sabrina; Cullinane, Ann M; Nghiem, Khanh; Sun, Clare; Valdez, Janet; Niemann, Carsten U; Herman, Sarah E M; Saba, Nakhle; Soto, Susan; Marti, Gerald; Uzel, Gulbu; Holland, Steve M; Lozier, Jay N; Wiestner, Adrian

2015-12-01

Ibrutinib is associated with bleeding-related adverse events of grade ≤ 2 in severity, and infrequently with grade ≥ 3 events. To investigate the mechanisms of bleeding and identify patients at risk, we prospectively assessed platelet function and coagulation factors in our investigator-initiated trial of single-agent ibrutinib for chronic lymphocytic leukemia. At a median follow-up of 24 months we recorded grade ≤ 2 bleeding-related adverse events in 55% of 85 patients. No grade ≥ 3 events occurred. Median time to event was 49 days. The cumulative incidence of an event plateaued by 6 months, suggesting that the risk of bleeding decreases with continued therapy. At baseline, von Willebrand factor and factor VIII levels were often high and normalized on treatment. Platelet function measured via the platelet function analyzer (PFA-100™) was impaired in 22 patients at baseline and in an additional 19 patients on ibrutinib (often transiently). Collagen and adenosine diphosphate induced platelet aggregation was tested using whole blood aggregometry. Compared to normal controls, response to both agonists was decreased in all patients with chronic lymphocytic leukemia, whether on ibrutinib or not. Compared to untreated chronic lymphocytic leukemia patients, response to collagen showed a mild further decrement on ibrutinib, while response to adenosine diphosphate improved. All parameters associated with a significantly increased risk of bleeding-related events were present at baseline, including prolonged epinephrine closure time (HR 2.74, P=0.012), lower levels of von Willebrand factor activity (HR 2.73, P=0.009) and factor VIII (HR 3.73, P=0.0004). In conclusion, both disease and treatment-related factors influence the risk of bleeding. Patients at greater risk for bleeding of grade ≤ 2 can be identified by clinical laboratory tests and counseled to avoid aspirin, non-steroidal anti-inflammatory drugs and fish oils. ClinicalTrials.gov identifier NCT01500733. Copyright© Ferrata Storti Foundation.

Incidence and risk factors of bleeding-related adverse events in patients with chronic lymphocytic leukemia treated with ibrutinib

PubMed Central

Lipsky, Andrew H.; Farooqui, Mohammed Z.H.; Tian, Xin; Martyr, Sabrina; Cullinane, Ann M.; Nghiem, Khanh; Sun, Clare; Valdez, Janet; Niemann, Carsten U.; Herman, Sarah E. M.; Saba, Nakhle; Soto, Susan; Marti, Gerald; Uzel, Gulbu; Holland, Steve M.; Lozier, Jay N.; Wiestner, Adrian

2015-01-01

Ibrutinib is associated with bleeding-related adverse events of grade ≤2 in severity, and infrequently with grade ≥3 events. To investigate the mechanisms of bleeding and identify patients at risk, we prospectively assessed platelet function and coagulation factors in our investigator-initiated trial of single-agent ibrutinib for chronic lymphocytic leukemia. At a median follow-up of 24 months we recorded grade ≤2 bleeding-related adverse events in 55% of 85 patients. No grade ≥3 events occurred. Median time to event was 49 days. The cumulative incidence of an event plateaued by 6 months, suggesting that the risk of bleeding decreases with continued therapy. At baseline, von Willebrand factor and factor VIII levels were often high and normalized on treatment. Platelet function measured via the platelet function analyzer (PFA-100™) was impaired in 22 patients at baseline and in an additional 19 patients on ibrutinib (often transiently). Collagen and adenosine diphosphate induced platelet aggregation was tested using whole blood aggregometry. Compared to normal controls, response to both agonists was decreased in all patients with chronic lymphocytic leukemia, whether on ibrutinib or not. Compared to untreated chronic lymphocytic leukemia patients, response to collagen showed a mild further decrement on ibrutinib, while response to adenosine diphosphate improved. All parameters associated with a significantly increased risk of bleeding-related events were present at baseline, including prolonged epinephrine closure time (HR 2.74, P=0.012), lower levels of von Willebrand factor activity (HR 2.73, P=0.009) and factor VIII (HR 3.73, P=0.0004). In conclusion, both disease and treatment-related factors influence the risk of bleeding. Patients at greater risk for bleeding of grade ≤2 can be identified by clinical laboratory tests and counseled to avoid aspirin, non-steroidal anti-inflammatory drugs and fish oils. ClinicalTrials.gov identifier NCT01500733 PMID:26430171

Potential supplementary utility of combined PFA-100 and functional von Willebrand factor testing for the laboratory assessment of desmopressin and factor concentrate therapy in von Willebrand disease.

PubMed

Favaloro, Emmanuel J; Thom, Jim; Patterson, David; Just, Sarah; Baccala, Maria; Dixon, Tracy; Meiring, Muriel; Koutts, Jerry; Rowell, John; Baker, Ross

2009-09-01

We performed a retrospective audit of cross-laboratory testing of desmopressin and factor concentrate therapy to assess the potential utility of supplementary testing using the PFA-100 with functional von Willebrand factor (VWF) activity testing. Data were evaluated for a large number of patients with von Willebrand disease of type 1, type 2A or type 2M, as well as a comparative subset of individuals with haemophilia or carriers of haemophilia. Laboratory testing comprised pre and postdesmopressin, or pre and postconcentrate, evaluation of factor VIII, VWF antigen (VWF:Ag) and VWF ristocetin cofactor activity as traditionally performed, supplemented with collagen-binding (VWF:CB) testing and PFA-100 closure times. In brief, both therapies tended to normalize VWF test parameters and closure times in individuals with type 1 von Willebrand disease, with the level of correction in closure times related to the level of normalization of VWF, particularly the VWF:CB. However, although occasional correction of closure times was observed in patients with type 2A or type 2M von Willebrand disease, these did not in general normalize PFA-100 closure times either with desmopressin or factor concentrate therapy. In these patients, improvement in closure times was more likely in those in whom VWF:CB values normalized or when VWF:CB/VWF:Ag ratios normalized. This study confirms that there is a strong relationship between the presenting levels of plasma VWF and PFA-100 closure times, and that the supplementary combination of PFA-100 and VWF:CB testing might provide added clinical utility to current broadly applied testing strategies limited primarily to VWF:Ag, VWF ristocetin cofactor and factor VIII:coagulant. Future prospective investigations are warranted to validate these relationships and to investigate their therapeutic implications.

Severe Hemophilia A in a Male Old English Sheep Dog with a C→T Transition that Created a Premature Stop Codon in Factor VIII

PubMed Central

Lozier, Jay N; Kloos, Mark T; Merricks, Elizabeth P; Lemoine, Nathaly; Whitford, Margaret H; Raymer, Robin A; Bellinger, Dwight A; Nichols, Timothy C

2016-01-01

Animals with hemophilia are models for gene therapy, factor replacement, and inhibitor development in humans. We have actively sought dogs with severe hemophilia A that have novel factor VIII mutations unlike the previously described factor VIII intron 22 inversion. A male Old English Sheepdog with recurrent soft-tissue hemorrhage and hemarthrosis was diagnosed with severe hemophilia A (factor VIII activity less than 1% of normal). We purified genomic DNA from this dog and ruled out the common intron 22 inversion; we then sequenced all 26 exons. Comparing the results with the normal canine factor VIII sequence revealed a C→T transition in exon 12 of the factor VIII gene that created a premature stop codon at amino acid 577 in the A2 domain of the protein. In addition, 2 previously described polymorphisms that do not cause hemophilia were present at amino acids 909 and 1184. The hemophilia mutation creates a new TaqI site that facilitates rapid genotyping of affected offspring by PCR and restriction endonuclease analyses. This mutation is analogous to the previously described human factor VIII mutation at Arg583, which likewise is a CpG dinucleotide transition causing a premature stop codon in exon 12. Thus far, despite extensive treatment with factor VIII, this dog has not developed neutralizing antibodies (‘inhibitors’) to the protein. This novel mutation in a dog gives rise to severe hemophilia A analogous to a mutation seen in humans. This model will be useful for studies of the treatment of hemophilia. PMID:27780008

Factoring in Factor VIII With Acute Ischemic Stroke.

PubMed

Siegler, James E; Samai, Alyana; Albright, Karen C; Boehme, Amelia K; Martin-Schild, Sheryl

2015-10-01

There is growing research interest into the etiologies of cryptogenic stroke, in particular as it relates to hypercoagulable states. An elevation in serum levels of the procoagulant factor VIII is recognized as one such culprit of occult cerebral infarctions. It is the objective of the present review to summarize the molecular role of factor VIII in thrombogenesis and its clinical use in the diagnosis and prognosis of acute ischemic stroke. We also discuss the utility of screening for serum factor VIII levels among patients at risk for, or those who have experienced, ischemic stroke. © The Author(s) 2015.

Comparative trial of the use of antiplatelet and oral anticoagulant in thrombosis prophylaxis in patients undergoing total cavopulmonary operation with extracardiac conduit: echocardiographic, tomographic, scintigraphic, clinical and laboratory analysis.

PubMed

Pessotti, Cristiane Felix Ximenes; Jatene, Marcelo Biscegli; Jatene, Ieda Biscegli; Oliveira, Patrícia Marques; Succi, Fabiana Moreira Passos; Moreira, Valeria de Melo; Lopes, Rafael Willain; Pedra, Simone Rolim Fernandes Fontes

2014-01-01

To compare the efficacy of aspirin and warfarin for prophylaxis of thrombosis in patients undergoing total cavopulmonary anastomosis. Evaluate whether coagulation factors (VII, VIII and protein C), clinical data, fenestration or hemodynamic factors, interfere with postoperative thrombosis. A prospective, randomized study of 30 patients, randomized into Group I (Warfarin) and Group II (AAS), underwent total cavopulmonary shunt with extracardiac conduit, between 2008 and 2011, with follow-up by clinical visits to evaluate side effects and adhesion. Performed transesophageal echocardiography in post operatory time, 3, 6,12 and 24 months; angiotomography at 6, 12 and 24 months to evaluate changes in the internal tube wall or thrombi and pulmonary scintigraphy to evaluate possible PTE. Two deaths in group I; 33.3% of patients had thrombus (46.7% in Group II). The previous occurrence of thrombus and low levels of coagulation protein C were the only factors that influenced the time free of thrombus (P=0.035 and 0.047). Angiotomographic evaluation: 35.7% in group II presented material accumulation greater than 2 mm (P=0.082). Scintigraphy: two patients had PTE in group II. Five patients had difficulty to comply with the treatment, 4 in group I with INR ranging from 1 to 6.4. The previous occurrence of thrombus is a risk factor for thrombosis in the postoperative period. Patients using AAS tend to deposit material in the tube wall. The small sample size did not allow to conclude which is the most effective drug in the prevention of thrombosis in this population.

Association of Serum Sex Hormones with Hemostatic Factors in Women On and Off Hormone Therapy: The Multiethnic Study of Atherosclerosis.

PubMed

Williams, Marlene S; Cushman, Mary; Ouyang, Pamela; Heckbert, Susan R; Kalyani, Rita Rastogi; Vaidya, Dhanajay

2016-02-01

Hormone therapy (HT) is associated with increased risk of both venous and arterial thrombosis, which are multifactorial in origin. Our objectives were twofold: first, we sought to examine associations between endogenous serum sex hormone levels and biomarkers of thrombosis and/or coagulation in postmenopausal hormone nonusers. Second, we separately studied the associations between serum sex hormone levels and biomarkers of thrombosis and/or coagulation in postmenopausal hormone users considering the fact that pattern of circulating hormones is different in women taking exogenous hormones. We performed a cross-sectional analysis of postmenopausal women enrolled in a large multiethnic community-based cohort study, The Multiethnic Study of Atherosclerosis. We hypothesized that higher levels of estrogen-related sex hormones would be associated with biomarkers of thrombosis, suggesting mechanisms for differences in thrombotic risk from HT. Women (n = 2878) were included if they were postmenopausal and had thrombotic biomarkers (homocysteine, fibrinogen, C-reactive protein [CRP], factor VIII, and d-dimer) and sex hormone levels (total testosterone [T], bioavailable testosterone, sex hormone binding globulin [SHBG], estradiol [E2], and dehydroepiandrosterone [DHEA]) measured. A smaller random sample of 491 women also had von Willebrand factor (vWF), plasminogen activator inhibitor (PAI-1), and tissue factor pathway inhibitor (TFPI) levels measured. We found that elevated levels of estradiol and SHBG in HT users were associated with elevated levels of CRP and lower levels of TFPI, both of which may be related to a prothrombotic milieu in HT users. HT nonusers had far more prothrombotic associations between elevated serum sex hormone levels and thrombotic biomarkers when compared with HT users.

Effect of two oral doses of 17beta-estradiol associated with dydrogesterone on thrombin generation in healthy menopausal women: a randomized double-blind placebo-controlled study.

PubMed

Rousseau, Alexandra; Robert, Annie; Gerotziafas, Grigoris; Torchin, Dahlia; Zannad, Faiez; Lacut, Karine; Libersa, Christian; Dasque, Eric; Démolis, Jean-Louis; Elalamy, Ismail; Simon, Tabassome

2010-04-01

Oral hormone therapy is associated with an increased risk of venous thrombosis. Drug agencies recommend the use of the lowest efficient dose to treat menopausal symptoms for a better risk/ratio profile, although this profile has not been totally investigated yet. The aim of the study was to compare the effect of the standard dose of 17beta-estradiol to a lower one on thrombin generation (TG). In a 2-month study, healthy menopausal women were randomized to receive daily 1mg or 2 mg of 17beta-estradiol (E1, n = 24 and E2, n = 26; respectively) with 10 mg dydrogesterone or placebo (PL, n = 22). Plasma levels factors VII, X, VIII and II were assessed before and after treatment as well as Tissue factor triggered TG, which allows the investigation of the different phases of coagulation process. The peak of thrombin was higher in hormone therapy groups (E1: 42.39 +/- 50.23 nm, E2: 31.08 +/- 85.86 nm vs. 10.52 +/- 40.63 nm in PL, P = 0.002 and P = 0.01). Time to reach the peak was also shortened (PL: 0.26 +/- 0.69 min vs. E1: -0.26 +/- 0.80 min, E2: -0.55 +/- 0.79 min, P <10(-3) for both comparisons) and mean rate index of the propagation phase of TG was significantly increased. Among the studied clotting factors, only the levels of FVII were significantly increased after treatment administration. The two doses of 17beta-estradiol induced in a similar degree an acceleration of the initiation and propagation phase of tissue factor triggered thrombin generation and a significant increase of FVII coagulant activity.

Factor VIII levels and the risk of pre-eclampsia, HELLP syndrome, pregnancy related hypertension and severe intrauterine growth retardation.

PubMed

Witsenburg, C P J; Rosendaal, F R; Middeldorp, J M; Van der Meer, F J M; Scherjon, S A

2005-01-01

Recently, acquired as well as genetic prothrombotic factors are associated with thrombotic events. These factors have also been related to conditions of uteroplacental insufficiency such as pre-eclampsia, HELLP syndrome and severe intrauterine growth restriction (IUGR). The aim of this study was to determine whether elevated factor VIII levels are associated with uteroplacental insufficiency, in particular pre-eclampsia, HELLP syndrome or pregnancy-induced hypertension and intrauterine growth retardation. Plasma samples of 75 women with a history of pregnancy complicated by pre-eclampsia, HELLP syndrome, pregnancy induced hypertension or intrauterine growth restriction were tested for factor VIII:C (FVIII:C) levels at a minimum of 10 weeks post-partum. Laboratory results were compared to factor VIII:C levels found in a healthy control group of 272 women. Mean factor VIII:C levels were similar at 123 IU/dl in both the patient group and the controls. In a logistic regression model, after adjusting for age and blood group, no effect of factor VIII:C levels on the risk of pregnancy complications was observed, with the exception of IUGR with (OR 2.9, CI 1.0-8.7) or without hypertension (OR 2.0, CI 0.7-6.4). If the elevated level of factor VIII would be the sole factor responsible for the increased risk observed, one would expect to find an effect of blood group on risk as well (blood group being an important determinant of FVIII:C). While no such effect could be shown a causal relationship between elevated levels of factor VIII and conditions of uteroplacental insufficiency such as pre-eclampsia, HELLP syndrome, pregnancy-induced hypertension and IUGR is not very likely.

Role of carbohydrate in multimeric structure of factor VIII/von Willebrand factor protein.

PubMed Central

Gralnick, H R; Williams, S B; Rick, M E

1983-01-01

The carbohydrate moiety of the factor VIII/von Willebrand (vW) factor protein is important in the expression of vW factor activity and the intravascular survival of the protein. Studies of normal human factor VIII/vW factor protein indicate that there is a requirement of a full complement of penultimate galactose for the maintenance of a normal multimeric structure. Release of penultimate galactose by beta-galactosidase or modification by galactose oxidase results in loss of the largest molecular weight multimers and increased numbers of intermediate and smaller multimers. In contrast, terminal galactose on the factor VIII/vW factor protein does not appear to play a significant role in the maintenance of the multimer organization. The abnormalities in multimeric structure and molecular size were demonstrated by NaDodSO4/polyacrylamide/agarose gel electrophoresis, NaDodSO4/glyoxyl-agarose electrophoresis, and sucrose density ultracentrifugation. These studies indicate that the penultimate galactose plays a role in the maintenance of the largest multimers of the factor VIII/vW factor protein. This may explain why, in some patients with variant forms of vW disease, a carbohydrate abnormality also may affect the multimeric structure of the plasma factor VIII/vW factor protein. Images PMID:6601805

Laboratory assessment of Activated Protein C Resistance/Factor V-Leiden and performance characteristics of a new quantitative assay.

PubMed

Amiral, Jean; Vissac, Anne Marie; Seghatchian, Jerard

2017-12-01

Activated Protein C Resistance is mainly associated to a factor V mutation (RQ506), which induces a deficient inactivation of activated factor V by activated protein C, and is associated to an increased risk of venous and arterial thrombosis in affected individuals, caused by the prolonged activated factor V survival. Its prevalence is mainly in Caucasians (about 5%), and this mutation is absent in Africans and Asians. Presence of Factor V-Leiden is usually evidenced with clotting methods, using a two-step APTT assay performed without or with APC: prolongation of blood coagulation time is decreased if this factor is present. The R506Q Factor V-Leiden mutation is now usually characterized using molecular biology, and this technique tends to become the first intention assay for characterization of patients. Both techniques are qualitative, and allow classifying tested individuals as heterozygotes or homozygotes for the mutation, when present. A new quantitative assay for Factor V-Leiden, using a one-step clotting method, has been developed, and designed with highly purified human coagulation proteins. Clotting is triggered with human Factor Xa, in presence of calcium and phospholipids (mixture which favours APC action over clotting process). Diluted tested plasma, is supplemented with a clotting mixture containing human fibrinogen, prothrombin, and protein S at a constant concentration. APC is added, and clotting is initiated with calcium. Calibration is performed with a pool of plasmas from patients carrying the R506Q Factor V mutation, and its mixtures with normal plasma. Homozygous patients have clotting times of about <40sec; heterozygous patients have clotting times of about 40-60sec and normal individuals yield clotting times >70sec. Factor V-Leiden concentration is usually >75% in homozygous patients, 30-60% in heterozygous patients and below 5% in normal. The assay is insensitive to clotting factor deficiencies (II, VII, VIII: C, IX, X), dicoumarol or heparin therapies, and has no interference with lupus anticoagulant (LA). This new assay for Factor V-Leiden can be easily used in any coagulation laboratory, is performed as a single test, and is quantitative. This assay has a high robustness, is accurate and presents a good intra- (<3%) and inter-assay (<5%) variability. It contributes solving most of the laboratory issues faced when testing factor V-Leiden. Quantitation of Factor V-L could contribute to a better assessment of thrombotic risk in affected patients, as this complication is first associated to and caused by the presence of a defined amount of FVa. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessment of the frequency of regulatory T cells (CD4+CD25+CD127-) in children with hemophilia A: relation to factor VIII inhibitors and disease severity.

PubMed

El-Asrar, Mohamed Abo; Hamed, Ahmed El-Saeed; Darwish, Yasser Wagih; Ismail, Eman Abdel Rahman; Ismail, Noha Ali

2016-01-01

A rapidly growing evidence showed that regulatory T cells (Tregs) play a crucial role in tolerance to coagulation factors and may be involved in the pathogenesis of inhibitor formation in patients with hemophilia. We determined the percentage of Tregs (CD4CD25CD127) in 45 children with hemophilia A compared with 45 healthy controls, and assessed their relation to the clinical characteristics of patients and factor VIII (FVIII) inhibitors. Patients were studied stressing on frequency of bleeding attacks, joint pain, history of viral hepatitis, and the received therapy (FVIII precipitate/cryotherapy). FVIII activity and FVIII inhibitors were assessed with flow cytometric analysis of CD4CD25CD127 Tregs. According to residual FVIII activity levels, 30 patients (66.7%) had mild/moderate hemophilia A, whereas 15 (33.3%) patients had severe hemophilia A. The frequency of Tregs was significantly lower among all patients with hemophilia A compared with controls (2.59 ± 1.1 versus 3.73 ± 1.12%; P = 0.002). Tregs were significantly decreased among patients with FVIII inhibitors compared with the inhibitor-negative group (P < 0.001). Patients with hematuria or severe hemophilia A had lower Tregs levels than those without (P = 0.34 and P = 0.011, respectively). A significant positive correlation was found between the percentage of Tregs and FVIII among hemophilia A patients. ROC curve analysis revealed that the cut-off value of Tregs at 1.91% could differentiate patients with and without FVIII inhibitors, with a sensitivity of 100% and a specificity of 91.3%. We suggest that alteration in the frequency of Tregs in young patients with hemophilia A may contribute to inhibitor formation and disease severity.

Epsilon-aminocaproic Acid for Treatment of Fibrinolysis during Liver Transplantation

PubMed Central

Kang, Yoogoo; Lewis, Jessica H.; Navalgund, Ashok; Russell, Michael W.; Bontempo, Franklin A.; Niren, Lawrence S.; Starzl, Thomas E.

2010-01-01

In 97 adult patients receiving liver transplants, the coagulation system was monitored by thrombelastography and by coagulation profile including PT; aPTT; platelet count; level of factors I, II, V, VII, VIII, IX, X, XI, and XII; fibrin degradation products; ethanol gel test; protamine gel test; and euglobulin lysis time. Preoperatively, fibrinolysis defined as a whole blood clot lysis index of less than 80% was present in 29 patients (29.9%), and a euglobulin lysis time of less than 1 h was present in 13 patients. Fibrinolysis increased progressively during surgery in 80 patients (82.5%) and was most severe on reperfusion of the graft liver in 33 patients (34%). When whole blood clot lysis (F < 180 min) was observed during reperfusion of the graft liver, blood coagulability was tested by thrombelastography using both a blood sample treated in vitro with ε-aminocaproic acid (0.09%) and an untreated sample. Blood treated with ε-aminocaproic acid showed improved coagulation without fibrinolytic activity in all 74 tests. When whole blood clot lysis time was less than 120 min, generalized oozing occurred, and the effectiveness of ε-aminocaproic acid was demonstrated in vitro during the pre-anhepatic and post-anhepatic stages, ε-aminocaproic acid (1 g, single intravenous dose) was administered. In all 20 patients treated with ε-aminocaproic acid, fibrinolytic activity disappeared; whole blood clot lysis was not seen on thrombelastography during a 5-h observation period, and whole blood clot lysis index improved from 28.5 ± 29.5% to 94.8 ± 7.4% (mean ± SD, P < 0.001). None of the treated patients had hemorrhagic or thrombotic complications. In patients undergoing liver transplantation, the judicious use of a small dose of ε-aminocaproic acid, when its efficacy was confirmed in vitro, effectively treated the severe fibrinolysis without clinical thrombotic complications. PMID:3296855

Identification of a His54Gln substitution in von Willebrand factor from a patient with defective binding of factor VIII.

PubMed

Rick, M E; Krizek, D M

1996-04-01

A patient with type 2N ("Normandy" variant) von Willebrand's disease is described. Her von Willebrand factor level was borderline low, while her factor VIII was markedly decreased to 7%. Her plasma von Willebrand factor demonstrated a decreased ability to complex with factor VIII in vitro, binding less than 10% when compared to normal plasma von Willebrand factor. The factor VIII released into the circulation after the patient received DDAVP had a shortened survival in vivo. Nucleotide sequence analysis revealed a T-to-A transition at nucleotide 2451 on both alleles. This transition results in a substitution of Gln for His at amino acid 54 in the mature subunit of von Willebrand factor.

Pathophysiology of shock and hemorrhage in a fulminating viral infection (Ebola).

PubMed

Fisher-Hoch, S P; Platt, G S; Neild, G H; Southee, T; Baskerville, A; Raymond, R T; Lloyd, G; Simpson, D I

1985-11-01

Eleven rhesus monkeys were monitored intensively during experimental infection with Ebola virus. Prominent neutrophilia with left shift and lymphopenia were the earliest abnormalities and were statistically significant by day 4 (P less than .02 and P less than .01, respectively). By day 4 falls in platelet counts were not statistically significant, whereas in vitro platelet aggregation was markedly depressed, progressing rapidly to complete failure by the time of maximum illness. Intraplatelet protein studies suggested this event was the result of in vivo activation and degranulation. Coagulation cascade defects were mainly in the intrinsic system and were surprisingly mild, with no evidence of selective consumption or production deficit of factor VII or VIII. When the possibility of indirectly mediated damage to endothelium possibly by a nonspecific immune response was examined, weight loss was less severe in drug-treated monkeys, and all had detectable plasma prostacyclin metabolites, but there was no improvement in survival.

Thrombo-ischaemic pinnal necrosis associated with fenbendazole treatment in a dog.

PubMed

Nuttall, T J; Burrow, R; Fraser, I; Kipar, A

2005-05-01

An 11-week-old, female West Highland white terrier was presented with necrosis of the distal third of both pinnae. Haematology, biochemistry and urinalysis, Coombs test, antinuclear antibody and cold autoagglutinin antibody tests were normal. A drug reaction to fenbendazole was diagnosed. The necrotic ear tips were surgically removed. Histopathology revealed extensive coagulative necrosis of the epidermis and superficial to mid-dermis, a moderate interstitial neutrophilic infiltrate and complete thrombotic occlusion and necrosis of blood vessels. There was also endothelial cell activation and proliferation with endothelial cell cushions protruding into the vascular lumen. Immunohistochemistry for factor VIII-related antigen confirmed endothelial cell involvement. This case represents an unusual, drug-induced, thrombo-ischaemic necrosis of the pinnae. It is also, to the authors' knowledge, the first report of fenbendazole sensitivity in a dog. The histopathology is similar to previous cases of proliferative thrombovascular pinnal necrosis, suggesting that drug reactions should be considered in this condition.

Localization of human coagulation factor VIII (hFVIII) in transgenic rabbit by FISH-TSA: identification of transgene copy number and transmission to the next generation.

PubMed

Krylov, V; Tlapáková, T; Mácha, J; Curlej, J; Ryban, L; Chrenek, P

2008-01-01

For chromosomal localization of the hFVIII human transgene in F2 and F3 generation of transgenic rabbits, FISH-TSA was applied. A short cDNA probe (1250 bp) targeted chromosomes 3, 7, 8, 9 and 18 of an F2 male (animal 1-3-8). Two transgenic offspring (F3) revealed signal positions in chromosome 3 and chromosomes 3 and 7, respectively. Sequencing and structure analysis of the rabbit orthologous gene revealed high similarity to its human counterpart. Part of the sequenced cDNA (1310 bp) served as a probe for FISH-TSA analysis. The rabbit gene was localized in the q arm terminus of the X chromosome. This result is in agreement with reciprocal chromosome painting between the rabbit and the human. The presented FISH-TSA method provides strong signals without any interspecies reactivity.

Relationship between development of post-thrombotic syndrome and serial ultrasound, D-dimer, and factor VIII activity after a first deep venous thrombosis.

PubMed

Roberts, Lara N; Patel, Raj K; Goss, David E; Chitongo, Paradzai; Bonner, Lynda; Arya, Roopen

2016-01-01

The aim of this study was to evaluate the relationship of post-thrombotic syndrome (PTS) with residual vein thrombosis, deep venous reflux (DVT), D-dimer, and factor VIII (FVIII) after a first deep venous thrombosis (DVT). There were 133 participants with objectively confirmed DVT, of whom 114 were observed for 6 months after completion of anticoagulation. Ultrasound, D-dimer, and FVIII evaluations were undertaken at 6 weeks after completion of anticoagulation and at the end of follow-up. PTS was considered present in those with a score of ≥5 on the Villalta scale at either assessment. The cumulative incidence of PTS was 51.8%, with median duration of follow-up of 11 months. Median D-dimer and FVIII in those with PTS were significantly higher at both time points compared with those without. Similarly, residual vein thrombosis and deep venous reflux were more prevalent in those with PTS at both study assessments. On multivariable analysis, only FVIII at end of study remained significantly associated with PTS with an odds ratio of 2.83 (95% confidence interval, 1.09-7.42; P = .034). Ultrasound markers and D-dimer were not significantly associated with PTS after adjustment for age, body mass index, Charlson Index ≥1, and proximal extent of DVT. FVIII activity at end of follow-up was independently associated with PTS, suggesting underlying activation of coagulation. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Antihuman factor VIII C2 domain antibodies in hemophilia A mice recognize a functionally complex continuous spectrum of epitopes dominated by inhibitors of factor VIII activation

PubMed Central

Meeks, Shannon L.; Healey, John F.; Parker, Ernest T.; Barrow, Rachel T.

2007-01-01

The diversity of factor VIII (fVIII) C2 domain antibody epitopes was investigated by competition enzyme-linked immunosorbent assay (ELISA) using a panel of 56 antibodies. The overlap patterns produced 5 groups of monoclonal antibodies (MAbs), designated A, AB, B, BC, and C, and yielded a set of 18 distinct epitopes. Group-specific loss of antigenicity was associated with mutations at the Met2199/Phe2200 phospholipid binding β-hairpin (group AB MAbs) and at Lys2227 (group BC MAbs), which allowed orientation of the epitope structure as a continuum that covers one face of the C2 β-sandwich. MAbs from groups A, AB, and B inhibit the binding of fVIIIa to phospholipid membranes. Group BC was the most common group and displayed the highest specific fVIII inhibitor activities. MAbs in this group are type II inhibitors that inhibit the activation of fVIII by either thrombin or factor Xa and poorly inhibit the binding of fVIII to phospholipid membranes or von Willebrand factor (VWF). Group BC MAbs are epitopically and mechanistically distinct from the extensively studied group C MAb, ESH8. These results reveal the structural and functional complexity of the anti-C2 domain antibody response and indicate that interference with fVIII activation is a major attribute of the inhibitor landscape. PMID:17848617

Development of freeze-dried albumin-free formulation of recombinant factor VIII SQ.

PubMed

Osterberg, T; Fatouros, A; Mikaelsson, M

1997-07-01

To develop a stable freeze-dried formulation of recombinant factor VIII-SQ (r-VIII SQ) without the addition of albumin. Different formulations were evaluated for their protective effect during sterile filtration, freeze-thawing, freeze-drying, reconstitution and long term storage. Factor VIII activity (VIII:C), visual inspection, clarity, solubility, moisture content and soluble aggregates and/ or fragments were assayed. A combination of non-crystallising excipients (L-histidine and sucrose), a non-ionic surfactant (polysorbate 80) and a crystalline bulking agent (sodium chloride) was found to preserve the factor VIII activity during formulation, freeze-drying and storage. Calcium chloride was included to prevent dissociation of the heavy and light chains of r-VIII SQ. Sodium chloride was chosen as the primary bulking agent since the concentration of sodium chloride necessary for dissolution of r-VIII SQ in the buffer will inhibit the crystallization of many potential cake formers. It was found that L-histidine, besides functioning as a buffer, also protected r-VIII SQ during freeze-drying and storage. A pH close to 7 was found to be optimal. Some potential macromolecular stabilisers, PEG 4000, Haes-steril and Haemaccel, were evaluated but they did not improve the recovery of VIII:C. The freeze-dried formulation was stable for at least two years at 7 degrees C and for at least one year at 25 degrees C. The reconstituted solution was stable for at least 100 hours at 25 degrees C. The albumin-free formulation resulted in consistently high recovery of VIII:C, very low aggregate formation and good storage stability. The stability of the reconstituted solution makes the formulation suitable for continuous administration via infusion pump. The formulation strategy described here may also be useful for other proteins which require a high ionic strength.

Prevalence of the intron 22 inversion of the factor VIII gene and inhibitor development in Polish patients with severe hemophilia A.

PubMed

Sawecka, Jadwiga; Skulimowska, Joanna; Windyga, Jerzy; Lopaciuk, Stanisław; Kościelak, Jerzy

2005-01-01

Patients with severe hemophilia A often develop inhibitors (antibodies) against transfused factor VIII. One hundred thirteen Polish patients with severe hemophilia A, who had been treated on demand with cryoprecipitate until 1992 and exclusively with factor VIII concentrates after 1995, were examined for intron 22 inversion by Southern blotting and the presence and magnitude of inhibitor activity in blood as determined by the Bethesda assay. The patients' ages ranged 4--67 years (mean: 33.7+/-12.4 years, median: 32 years). The number of patients with the inversion amounted to 57, while in 56 patients the mutation types were unknown; 47 patients had a distal and 10 patients a proximal type of inversion. Thirteen patients with inversions (22.8%) were found to have inhibitor in their blood. Most patients (14 out of 15) who developed inhibitors in the course of cryoprecipitate therapy were high responders. Conversely, 4 of 5 patients treated between 1992 and 1995 with both cryoprecipitate and intermediate-purity factor VIII concentrates were low responders. One multitransfused patient who had remained inhibitor-free on cryoprecipitate therapy developed inhibitor after receiving a large dose of factor VIII concentrate during surgery. None of these 5 patients developed inhibitors during their 12--40 years of treatment with cryoprecipitate, suggesting that it was less immunogenic than factor VIII concentrates. The prevalence of the intron 22 inversion mutation of the factor VIII gene in Polish hemophiliacs is similar to that in other European countries. Treatment regimens with either cryoprecipitate or virus-inactivated plasma-derived factor VIII concentrates may affect inhibitor formation in hemophilia A patients.

AAV5-Factor VIII Gene Transfer in Severe Hemophilia A.

PubMed

Rangarajan, Savita; Walsh, Liron; Lester, Will; Perry, David; Madan, Bella; Laffan, Michael; Yu, Hua; Vettermann, Christian; Pierce, Glenn F; Wong, Wing Y; Pasi, K John

2017-12-28

Patients with hemophilia A rely on exogenous factor VIII to prevent bleeding in joints, soft tissue, and the central nervous system. Although successful gene transfer has been reported in patients with hemophilia B, the large size of the factor VIII coding region has precluded improved outcomes with gene therapy in patients with hemophilia A. We infused a single intravenous dose of a codon-optimized adeno-associated virus serotype 5 (AAV5) vector encoding a B-domain-deleted human factor VIII (AAV5-hFVIII-SQ) in nine men with severe hemophilia A. Participants were enrolled sequentially into one of three dose cohorts (low dose [one participant], intermediate dose [one participant], and high dose [seven participants]) and were followed through 52 weeks. Factor VIII activity levels remained at 3 IU or less per deciliter in the recipients of the low or intermediate dose. In the high-dose cohort, the factor VIII activity level was more than 5 IU per deciliter between weeks 2 and 9 after gene transfer in all seven participants, and the level in six participants increased to a normal value (>50 IU per deciliter) that was maintained at 1 year after receipt of the dose. In the high-dose cohort, the median annualized bleeding rate among participants who had previously received prophylactic therapy decreased from 16 events before the study to 1 event after gene transfer, and factor VIII use for participant-reported bleeding ceased in all the participants in this cohort by week 22. The primary adverse event was an elevation in the serum alanine aminotransferase level to 1.5 times the upper limit of the normal range or less. Progression of preexisting chronic arthropathy in one participant was the only serious adverse event. No neutralizing antibodies to factor VIII were detected. The infusion of AAV5-hFVIII-SQ was associated with the sustained normalization of factor VIII activity level over a period of 1 year in six of seven participants who received a high dose, with stabilization of hemostasis and a profound reduction in factor VIII use in all seven participants. In this small study, no safety events were noted, but no safety conclusions can be drawn. (Funded by BioMarin Pharmaceutical; ClinicalTrials.gov number, NCT02576795 ; EudraCT number, 2014-003880-38 .).

Gene-centric approach identifies new and known loci for FVIII activity and VWF antigen levels in European Americans and African Americans

PubMed Central

Tang, Weihong; Cushman, Mary; Green, David; Rich, Stephen S.; Lange, Leslie A.; Yang, Qiong; Tracy, Russell P.; Tofler, Geoffrey H.; Basu, Saonli; Wilson, James G.; Keating, Brendan J.; Weng, Lu-Chen; Taylor, Herman A.; Jacobs, David R.; Delaney, Joseph A.; Palmer, Cameron D.; Young, Taylor; Pankow, James S.; O'Donnell, Christopher J.; Smith, Nicholas L.; Reiner, Alexander P.; Folsom, Aaron R.

2016-01-01

Coagulation factor VIII and von Willebrand factor (VWF) are key proteins in procoagulant activation. Higher FVIII coagulant activity (FVIII:C) and VWF antigen (VWF:Ag) are risk factors for cardiovascular disease and venous thromboembolism. Beyond associations with ABO blood group, genetic determinants of FVIII and VWF are not well understood, especially in non European-American populations. We performed a genetic association study of FVIII:C and VWF:Ag that assessed 50,000 gene-centric single nucleotide polymorphisms (SNPs) in 18,556 European Americans (EAs) and 5,047 African Americans (AAs) from five population-based cohorts. Previously unreported associations for FVIII:C were identified in both AAs and EAs with KNG1 (most significantly associated SNP rs710446, Ile581Thr, P=5.10 × 10−7 in EAs and P=3.88 × 10−3 in AAs) and VWF rs7962217 (Gly2705Arg, P=6.30 × 10−9 in EAs and P=2.98 × 10−2 in AAs). Significant associations for FVIII:C were also observed with F8/TMLHE region SNP rs12557310 in EAs (P=8.02 × 10−10), with VWF rs1800380 in AAs (P=5.62 × 10−11), and with MAT1A rs2236568 in AAs (P=1.69 × 10−6). We replicated previously reported associations of FVIII:C and VWF:Ag with the ABO blood group, VWF rs1063856 (Thr789Ala), rs216321 (Ala852Gln), and VWF rs2229446 (Arg2185Gln). Findings from this study expand our understanding of genetic influences for FVIII:C and VWF:Ag in both EAs and AAs. PMID:25779970

Quantitative evaluation of plasma after methylene blue and white light treatment in four Chinese blood centers.

PubMed

Chunhui, Yang; Guohui, Bian; Hong, Yang; Xiaopu, Xiao; Zherong, Bai; Mingyuan, Wang; Xinsheng, Zhang; Juanjuan, Wang; Changqing, Li; Wuping, Li

2013-12-01

Pathogen reduction technology is an important process in the blood safety system, including solvent/detergent treatment, filtration and methylene blue-photochemical technology (MB-PCT). To investigate the quality of MB-PCT-treated plasma, plasma samples from four Chinese blood centers were analyzed over 12 months of storage to determine the recovery of activities and levels of various plasma proteins. Ten plasma units each from the Suzhou, Yancheng, Chongqing and Shandong blood centers were divided into two aliquots. One was subjected to treatment with one of two methylene blue-photochemical technology instruments and the other was used as control. The treated and untreated sample pairs were stored at -30°C. The recovery rates of coagulation factors, inhibitor proteins, total protein, immunoglobulins, and complement proteins were measured at different time points after storage. The mean recovery of most proteins exceeded 80% after MB treatment. The exceptions were factor XI and fibrinogen, of which only 71.3-74% and 69.0-92.3% were retained during storage. The two equipment types differed in terms of residual MB concentration in the plasma samples (0.18 μM and 0.29 μM, respectively). They had similar protein recovery rates at 0.5 month but differed at later time points. The four blood centers differed significantly with regard to factor II, V, VIII and fibrinogen activities. Only the samples from the Shandong blood center met the methylene blue treated fresh frozen plasma requirement. The major factor that influenced the quality of the MB-FFP samples was the time taken between blood collection and storage. Methylene blue treated plasma showed reduced coagulation factor (CF) activity and protein levels. The MB treatment-induced damage to the proteins was acceptable at the four Chinese blood centers, but the quality of the MB-treated plasma in general was not satisfactory. The main factor affecting plasma quality may be the duration of the collection and processing. Copyright © 2013 Elsevier Ltd. All rights reserved.

Persons with Haemophilia in Sweden- Experiences and Strategies in Everyday Life. A Single Centre Study

PubMed Central

2015-01-01

Introduction/Aim Haemophilia is caused by deficiency in coagulation factor VIII or IX. Treatment with the missing coagulation factors has been available in most developed countries for several decades. The aim was to explore the experiences of adults living with severe or moderate haemophilia and their coping strategies at a single centre in Sweden. Method The interview study had a qualitative empirical approach and was analyzed on the basis of the method empirical phenomenological psychology. The sample included 14 participants, mean age 42 (19–80 y), who met the inclusion criteria and to saturation of information. Results: General characteristics were; All were satisfied with and grateful for access to medication. An acceptance of the disorder and willingness to live a normal life was identified among all participants. They were all content with the care provided by Haemophilia Treatment Centre (HTC) and felt supported by its multidisciplinary team. Four typologies were identified; Protective adults and assertive children during up-bringing, finding a role in social context, symptoms and treatments, fear of limited resources in the future. Task-, emotional- and avoidance coping strategies were seen in the interviews. The most prominent coping strategy was task oriented. Conclusion This interview study with Swedish PWH shows that they strive for normality and adaptation in social activities throughout life finding their own niche. The PWH expressed the importance of knowledge and support from the comprehensive medical team at HTC and therefore it seems important to continue comprehensive medical care at HTC in order to follow-up the haemophilia persons regularly. PMID:26431432

Lipid nanotechnologies for structural studies of membrane-associated proteins.

PubMed

Stoilova-McPhie, Svetla; Grushin, Kirill; Dalm, Daniela; Miller, Jaimy

2014-11-01

We present a methodology of lipid nanotubes (LNT) and nanodisks technologies optimized in our laboratory for structural studies of membrane-associated proteins at close to physiological conditions. The application of these lipid nanotechnologies for structure determination by cryo-electron microscopy (cryo-EM) is fundamental for understanding and modulating their function. The LNTs in our studies are single bilayer galactosylceramide based nanotubes of ∼20 nm inner diameter and a few microns in length, that self-assemble in aqueous solutions. The lipid nanodisks (NDs) are self-assembled discoid lipid bilayers of ∼10 nm diameter, which are stabilized in aqueous solutions by a belt of amphipathic helical scaffold proteins. By combining LNT and ND technologies, we can examine structurally how the membrane curvature and lipid composition modulates the function of the membrane-associated proteins. As proof of principle, we have engineered these lipid nanotechnologies to mimic the activated platelet's phosphtaidylserine rich membrane and have successfully assembled functional membrane-bound coagulation factor VIII in vitro for structure determination by cryo-EM. The macromolecular organization of the proteins bound to ND and LNT are further defined by fitting the known atomic structures within the calculated three-dimensional maps. The combination of LNT and ND technologies offers a means to control the design and assembly of a wide range of functional membrane-associated proteins and complexes for structural studies by cryo-EM. The presented results confirm the suitability of the developed methodology for studying the functional structure of membrane-associated proteins, such as the coagulation factors, at a close to physiological environment. © 2014 Wiley Periodicals, Inc.

A high-potency, single-donor cryoprecipitate of known factor VIII content dispensed in vials.

PubMed

McLeod, B C; Sassetti, R J; Cole, E R; Scott, J P

1987-01-01

Current factor VIII products expose recipients to many donors and hence to a high risk of acquiring blood-borne infections. Plasma-exchange donation of cryoprecipitate can reduce donor exposure by repeatedly obtaining large yields of factor VIII from individual donors. In this study, donor factor VIII levels were stimulated with desmopressin before donation. Mean yield per donation increased from 1399 +/- 425 IU in controls to 3818 +/- 1350 IU in stimulated donations (p less than 0.001), and mean factor VIII concentration in the cryoprecipitate increased from 8.2 +/- 3 IU/mL to 24 +/- 12 IU/mL (p less than 0.001). A new packaging system dispenses assayed aliquots of stimulated cryoprecipitate in plastic vials. The direct cost of production for this material is $.065 per unit. The cryoprecipitate is hemostatically active and convenient to use, and the aggregate yields from sequential donations by stimulated persons are high enough to allow long-term, single-donor support of many adults with hemophilia.

Bioequivalence between two serum-free recombinant factor VIII preparations (N8 and ADVATE®)--an open-label, sequential dosing pharmacokinetic study in patients with severe haemophilia A.

PubMed

Martinowitz, U; Bjerre, J; Brand, B; Klamroth, R; Misgav, M; Morfini, M; Santagostino, E; Tiede, A; Viuff, D

2011-11-01

Recombinant coagulation factor VIII (rFVIII) concentrates provide a safe and efficacious replacement therapy for treatment and prevention of bleeding in patients with severe haemophilia A. The aim of this study was to compare the pharmacokinetic (PK) and safety profiles of two serum-free rFVIII products: N8, a new rFVIII manufactured by Novo Nordisk and Advate(®), a marketed product. Patients with severe haemophilia A with >150 exposure days to FVIII, without current or past inhibitors, were enrolled in an open-label, first human dose (FHD), multicentre trial. Twenty-three patients first received a single dose of 50 IU kg(-1) body weight Advate(®) followed by 50 IU kg(-1) body weight N8 at the next visit. A 4-day washout period was required prior to each dosing. Blood samples for PK and safety analyses were drawn prior to dosing and at intervals up until 48 h postdosing. The PK parameters were based on FVIII clotting activity (FVIII:C) measurements. Occurrence of adverse events was closely monitored. The mean profiles of FVIII:C and all primary and secondary parameters for Advate(®) and N8 were comparable. The 90% CI for the treatment ratio (Advate(®)/N8) for all primary endpoints (incremental recovery, t(1/2), AUC and Cl), and the secondary endpoints (AUC(last) and C(max)) were within the bioequivalence interval of 0.8-1.25. There were no safety concerns in the study and no reports of inhibitor formation in the 72-h period following exposure to a single N8 dose. In conclusion, N8 is bioequivalent to Advate(®). Furthermore, N8 is well tolerated in the FHD trial. © 2011 Blackwell Publishing Ltd.

Joint health scores in a haemophilia A cohort from Pakistan with minimal or no access to factor VIII concentrate: correlation with thrombin generation and underlying mutation.

PubMed

Khanum, F; Bowen, D J; Kerr, B C; Collins, P W

2014-05-01

Haemophilia A is associated with recurrent joint bleeding which leads to synovitis and debilitating arthropathy. Coagulation factor VIII level is an important determinant of bleed number and development of arthropathy . The aim of this study was to compare the haemophilia joint health score (HJHS) and Gilbert score with severity, age, thrombin generation (TG) and underlying mutation in a haemophilia A cohort which had minimal access to haemostatic replacement therapy. Ninety-two haemophilia A individuals were recruited from Pakistan. Age, age at first bleed, target joints, haemophilic arthropathy joints, HJHS and Gilbert score were recorded. A strong correlation was found between HJHS and Gilbert score (r = 0.98), both were significantly higher in severe (n = 59) compared with non-severe (n = 29) individuals before the age of 12 years (P ≤ 0.01) but not thereafter. When individuals were divided according to developmental age (<12 years, 12-16 years and >16 years), both HJHS and Gilbert score were significantly lower in the youngest group (P ≤ 0.001), there was no difference between 12-16 years and >16 years. In severe individuals there was no correlation between in vitro TG and joint score, whereas in non-severe individuals there was a weak negative correlation. In the severe group, no significant difference was observed for either joint score according to the underlying mutation type (inversion, missense, nonsense, frameshift). In this cohort of haemophilia A individuals with minimal access to haemostatic treatment, haemophilic arthropathy correlated with severity and age; among severe individuals, joint health scores did not relate to either the underlying mutation or in vitro TG. © 2013 John Wiley & Sons Ltd.

A Pharmacometric Approach to Substitute for a Conventional Dose-Finding Study in Rare Diseases: Example of Phase III Dose Selection for Emicizumab in Hemophilia A.

PubMed

Yoneyama, Koichiro; Schmitt, Christophe; Kotani, Naoki; Levy, Gallia G; Kasai, Ryu; Iida, Satofumi; Shima, Midori; Kawanishi, Takehiko

2017-12-06

Emicizumab (ACE910) is a bispecific antibody mimicking the cofactor function of activated coagulation factor VIII. In phase I-I/II studies, emicizumab reduced the bleeding frequency in patients with severe hemophilia A, regardless of the presence of factor VIII inhibitors, at once-weekly subcutaneous doses of 0.3, 1, and 3 mg/kg. Using the phase I-I/II study data, population pharmacokinetic and repeated time-to-event (RTTE) modeling were performed to quantitatively characterize the relationship between the pharmacokinetics of emicizumab and reduction in bleeding frequency. Simulations were then performed to identify the minimal exposure expected to achieve zero bleeding events for 1 year in at least 50% of patients and to select the dosing regimens to be tested in phase III studies. The RTTE model adequately predicted the bleeding onset over time as a function of plasma emicizumab concentration. Simulations suggested that plasma emicizumab concentrations of ≥  45 μg/mL should result in zero bleeding events for 1 year in at least 50% of patients. This efficacious exposure provided the basis for selecting previously untested dosing regimens of 1.5 mg/kg once weekly, 3 mg/kg every 2 weeks, and 6 mg/kg every 4 weeks for phase III studies. A pharmacometric approach guided the phase III dose selection of emicizumab in hemophilia A, without conducting a conventional dose-finding study. Phase III studies with the selected dosing regimens are currently ongoing. This case study indicates that a pharmacometric approach can substitute for a conventional dose-finding study in rare diseases and will streamline the drug development process.

The pharmacokinetics of a B-domain truncated recombinant factor VIII, turoctocog alfa (NovoEight®), in patients with hemophilia A.

PubMed

Jiménez-Yuste, V; Lejniece, S; Klamroth, R; Suzuki, T; Santagostino, E; Karim, F A; Saugstrup, T; Møss, J

2015-03-01

Turoctocog alfa (NovoEight(®)) is a human recombinant coagulation factor VIII (rFVIII) for the treatment of patients with hemophilia A. To evaluate the pharmacokinetics of turoctocog alfa in all age groups across clinical trials. Data from previously treated patients with severe hemophilia A (FVIII activity level of ≤ 1%) with no history of FVIII inhibitors, in a non-bleeding state, were included. The pharmacokinetics were assessed following a wash-out period and a subsequent single intravenous 50 IU kg(-1) dose of turoctocog alfa. Blood was sampled during a 48-h period postdose. Standard pharmacokinetic (PK) parameters were estimated on the basis of plasma FVIII activity vs. time (PK profiles) with non-compartmental methods. Furthermore, a population PK analysis was conducted. Data from 76 patients (aged 1-60 years) enrolled globally across six clinical trials were included, totaling 105 turoctocog alfa PK profiles. Single-dose PK results 3-6 months after the first dose of turoctocog alfa were comparable with the results obtained after the first dose. Similar PK characteristics were shown for different lots and strengths of the drug product. Overall, area under the plasma concentration (activity) curve from administration to infinity (AUC) and t1(/2) tended to increase with increasing age, with lower AUC and shorter t(1/2) being seen in children than in adolescents and adults. The PK profiles of turoctocog alfa and other commercially available plasma-derived FVIII and rFVIII products were similar in all age groups. The PK characteristics of turoctocog alfa have been thoroughly studied, and shown to be consistent over time, reproducible between different lots and strengths of drug product, and similar to those observed for other FVIII products. © 2014 International Society on Thrombosis and Haemostasis.

High-affinity, noninhibitory pathogenic C1 domain antibodies are present in patients with hemophilia A and inhibitors

PubMed Central

Batsuli, Glaivy; Deng, Wei; Healey, John F.; Parker, Ernest T.; Baldwin, W. Hunter; Cox, Courtney; Nguyen, Brenda; Kahle, Joerg; Königs, Christoph; Li, Renhao; Lollar, Pete

2016-01-01

Inhibitor formation in hemophilia A is the most feared treatment-related complication of factor VIII (fVIII) therapy. Most inhibitor patients with hemophilia A develop antibodies against the fVIII A2 and C2 domains. Recent evidence demonstrates that the C1 domain contributes to the inhibitor response. Inhibitory anti-C1 monoclonal antibodies (mAbs) have been identified that bind to putative phospholipid and von Willebrand factor (VWF) binding epitopes and block endocytosis of fVIII by antigen presenting cells. We now demonstrate by competitive enzyme-linked immunosorbent assay and hydrogen-deuterium exchange mass spectrometry that 7 of 9 anti-human C1 mAbs tested recognize an epitope distinct from the C1 phospholipid binding site. These mAbs, designated group A, display high binding affinities for fVIII, weakly inhibit fVIII procoagulant activity, poorly inhibit fVIII binding to phospholipid, and exhibit heterogeneity with respect to blocking fVIII binding to VWF. Another mAb, designated group B, inhibits fVIII procoagulant activity, fVIII binding to VWF and phospholipid, fVIIIa incorporation into the intrinsic Xase complex, thrombin generation in plasma, and fVIII uptake by dendritic cells. Group A and B epitopes are distinct from the epitope recognized by the canonical, human-derived inhibitory anti-C1 mAb, KM33, whose epitope overlaps both groups A and B. Antibodies recognizing group A and B epitopes are present in inhibitor plasmas from patients with hemophilia A. Additionally, group A and B mAbs increase fVIII clearance and are pathogenic in a hemophilia A mouse tail snip bleeding model. Group A anti-C1 mAbs represent the first identification of pathogenic, weakly inhibitory antibodies that increase fVIII clearance. PMID:27381905

Impact of blood hypercoagulability on in vitro fertilization outcomes: a prospective longitudinal observational study.

PubMed

Gerotziafas, Grigoris T; Van Dreden, Patrick; Mathieu d'Argent, Emmanuelle; Lefkou, Eleftheria; Grusse, Matthieu; Comtet, Marjorie; Sangare, Rabiatou; Ketatni, Hela; Larsen, Annette K; Elalamy, Ismail

2017-01-01

Blood coagulation plays a crucial role in the blastocyst implantation process and its alteration may be related to in vitro fertilization (IVF) failure. We conducted a prospective observational longitudinal study in women eligible for IVF to explore the association between alterations of coagulation with the IVF outcome and to identify the biomarkers of hypercoagulability which are related with this outcome. Thirty-eight women eligible for IVF (IVF-group) and 30 healthy, age-matched women (control group) were included. In the IVF-group, blood was collected at baseline, 5-8 days after administration of gonadotropin-releasing hormone agonist (GnRH), before and two weeks after administration of human follicular stimulating hormone (FSH). Pregnancy was monitored by measurement of β HCG performed 15 days after embryo transfer. Thrombin generation (TG), minimal tissue factor-triggered whole blood thromboelastometry (ROTEM®), procoagulant phospholipid clotting time (Procoag-PPL®), thrombomodulin (TMa), tissue factor activity (TFa), factor VIII (FVIII), factor von Willebrand (FvW), D-Dimers and fibrinogen were assessed at each time point. Positive IVF occurred in 15 women (40%). At baseline, the IVF-group showed significantly increased TG, TFa and TMa and significantly shorter Procoag-PPL versus the control group. After initiation of hormone treatment TG was significantly higher in the IVF-positive as compared to the IVF-negative group. At all studied points, the Procoag-PPL was significantly shorter and the levels of TFa were significantly higher in the IVF-negative group compared to the IVF-positive one. The D-Dimers were higher in the IVF negative as compared to IVF positive group. Multivariate analysis retained the Procoag-PPL and TG as predictors for the IVF outcome. Diagnosis of women with hypercoagulability and their stratification to risk of IVF failure using a model based on the Procoag-PPL and TG is a feasible strategy for the optimization of IVF efficiency that needs to be validated in prospective trials.

A short history of diagnostic tests for von Willebrand disease: in memory of Barry Firkin (1930 to 2001) and Ted Zimmerman (1937 to 1988).

PubMed

Koutts, Jerry

2006-07-01

By the end of the 1960s, von Willebrand disease (vWD) was accepted as a combined deficiency of factor (F) VIII coagulation and a plasma factor responsible for normal platelet adhesion. Just how these two functions related to each other was unclear, and the diagnostic tests available at the time were poorly reproducible, cumbersome, and unreliable. As a consequence, the condition was poorly delineated from other coagulation and platelet disorders. In the early 1970s, ristocetin-induced platelet aggregation was described and formed the basis of the first consistent and reliable test that quantified the platelet adhesive function missing in vWD. Immunoprecipitating techniques specific for the molecule missing in vWD were defined. The application of these technologies allowed a clearer understanding of the heterogeneity of vWD and continues to form a basis for the diagnosis of this condition. Concurrently, exploration of the structure and function of von Willebrand factor (vWF) has contributed greatly to the understanding of platelet physiology, ligand receptor interaction, and pathways of cellular interaction and activation. Despite all of the progress during the last 35 years, including extensive developments in the field of molecular biology and genetics of vWD, the diagnosis of this condition in many, if not most cases, remains controversial. The final plasma level of vWF is influenced substantially by epigenetic and environmental factors. This natural heterogeneity is further compounded by significant imprecision of existing tests. As a consequence, defining vWD on the basis of a variation from the normal range alone is more than likely to be incorrect. The high frequency of a positive bleeding disorder in the normal population does not assist discrimination. It has been suggested that the diagnosis of mild type 1 vWD be discarded because it does not exhibit consistent linkage to the VWF gene and does not predict bleeding.

Efficient stabilization of recombinant human coagulation factor VIII in the milk of transgenic mice using hFVIII and vWF co-expression vector transduction.

PubMed

Ren, Xiaoye; Gong, Xiuli; Cai, Qin; Guo, Xinbing; Xu, Miao; Ren, Zhaorui; Zeng, Yitao

2015-06-01

To investigate the reasons for the instability of human coagulation factor FVIII (hFVIII) in milk which is an intractable obstacle during the hFVIII production by a transgenic mammary gland bioreactor. We constructed P1A3-hFVIIIBDD and P1A3-hFVIIIBDD-IRES-vWF co-expression cassettes for generating transgenic mice. P1A3-hFVIII/CMV-vWF double heterozygotes were also prepared by mating P1A3-hFVIIIBDD with CMV-vWF mice. hFVIII bioactivity in milk was determined under different storage conditions. The half-life (in vitro) of hFVIII bioactivity in P1A3-hFVIIIBDD-IRES-vWF mice was significantly longer than P1A3-hFVIIIBDD mice [77 ± 4.9 vs. 44 ± 2.6 h at 4 °C, 32.5 ± 5 vs. 19.7 ± 0.6 h at room temperature and 7.4 ± 1.4 vs. 3.4 ± 0.6 at 37 °C, respectively (P < 0.05)]. The half-life (in vitro) of hFVIII bioactivity in milk of double heterozygotes was similar to P1A3-hFVIIIBDD-IRES-vWF ones, demonstrating that the vWF transgene expression in hFVIII transgenic mice can efficiently improve the stabilization of hFVIII bioactivity in milk. We provide a new approach of P1A3-hFVIIIBDD-IRES-vWF co-expression to generate more stable hFVIII in transgenic milk with rapid and low cost as well as valuable information for producing pharmaceutical proteins by transgenic mammary gland bioreactor.

Efficacy and safety of rVIII-SingleChain: results of a phase 1/3 multicenter clinical trial in severe hemophilia A

PubMed Central

Mahlangu, Johnny; Kuliczkowski, Kazimierz; Karim, Faraizah Abdul; Stasyshyn, Oleksandra; Kosinova, Marina V.; Lepatan, Lynda Mae; Skotnicki, Aleksander; Boggio, Lisa N.; Klamroth, Robert; Oldenburg, Johannes; Hellmann, Andrzej; Santagostino, Elena; Baker, Ross I.; Fischer, Kathelijn; Gill, Joan C.; P’Ng, Stephanie; Chowdary, Pratima; Escobar, Miguel A.; Khayat, Claudia Djambas; Rusen, Luminita; Bensen-Kennedy, Debra; Blackman, Nicole; Limsakun, Tharin; Veldman, Alex; St. Ledger, Katie

2016-01-01

Recombinant VIII (rVIII)-SingleChain is a novel B-domain–truncated recombinant factor VIII (rFVIII), comprised of covalently bonded factor VIII (FVIII) heavy and light chains. It was designed to have a higher binding affinity for von Willebrand factor (VWF). This phase 1/3 study investigated the efficacy and safety of rVIII-SingleChain in the treatment of bleeding episodes, routine prophylaxis, and surgical prophylaxis. Participants were ≥12 years of age, with severe hemophilia A (endogenous FVIII <1%). The participants were allocated by the investigator to receive rVIII-SingleChain in either an on-demand or prophylaxis regimen. Of the 175 patients meeting study eligibility criteria, 173 were treated with rVIII-SingleChain, prophylactically (N = 146) or on-demand (N = 27). The total cumulative exposure was 14 306 exposure days (EDs), with 120 participants reaching ≥50 EDs and 52 participants having ≥100 EDs. Hemostatic efficacy was rated by the investigator as excellent or good in 93.8% of the 835 bleeds treated and assessed. Across all prophylaxis regimens, the median annualized spontaneous bleeding rate was 0.00 (Q1, Q3: 0.0, 2.4) and the median overall annualized bleeding rate (ABR) was 1.14 (Q1, Q3: 0.0, 4.2). Surgical hemostasis was rated as excellent/good in 100% of major surgeries by the investigator. No participant developed FVIII inhibitors. In conclusion, rVIII-SingleChain is a novel rFVIII molecule showing excellent hemostatic efficacy in surgery and in the control of bleeding events, low ABR in patients on prophylaxis, and a favorable safety profile in this large clinical study. This trial was registered at www.clinicaltrials.gov as #NCT01486927. PMID:27330001

Hemostatic effect of a monoclonal antibody mAb 2021 blocking the interaction between FXa and TFPI in a rabbit hemophilia model.

PubMed

Hilden, Ida; Lauritzen, Brian; Sørensen, Brit Binow; Clausen, Jes Thorn; Jespersgaard, Christina; Krogh, Berit Olsen; Bowler, Andrew Neil; Breinholt, Jens; Gruhler, Albrecht; Svensson, L Anders; Petersen, Helle Heibroch; Petersen, Lars Christian; Balling, Kristoffer W; Hansen, Lene; Hermit, Mette Brunsgaard; Egebjerg, Thomas; Friederichsen, Birgitte; Ezban, Mirella; Bjørn, Søren Erik

2012-06-14

Hemophilia is treated by IV replacement therapy with Factor VIII (FVIII) or Factor IX (FIX), either on demand to resolve bleeding, or as prophylaxis. Improved treatment may be provided by drugs designed for subcutaneous and less frequent administration with a reduced risk of inhibitor formation. Tissue factor pathway inhibitor (TFPI) down-regulates the initiation of coagulation by inhibition of Factor VIIa (FVIIa)/tissue factor/Factor Xa (FVIIa/TF/FXa). Blockage of TFPI inhibition may facilitate thrombin generation in a hemophilic setting. A high-affinity (K(D) = 25pM) mAb, mAb 2021, against TFPI was investigated. Binding of mAb 2021 to TFPI effectively prevented inhibition of FVIIa/TF/FXa and improved clot formation in hemophilia blood and plasma. The binding epitope on the Kunitz-type protease inhibitor domain 2 of TFPI was mapped by crystallography, and showed an extensive overlap with the FXa contact region highlighting a structural basis for its mechanism of action. In a rabbit hemophilia model, an intravenous or subcutaneous dose significantly reduced cuticle bleeding. mAb 2021 showed an effect comparable with that of rFVIIa. Cuticle bleeding in the model was reduced for at least 7 days by a single intravenous dose of mAb 2021. This study suggests that neutralization of TFPI by mAb 2021 may constitute a novel treatment option in hemophilia.

High-affinity, noninhibitory pathogenic C1 domain antibodies are present in patients with hemophilia A and inhibitors.

PubMed

Batsuli, Glaivy; Deng, Wei; Healey, John F; Parker, Ernest T; Baldwin, W Hunter; Cox, Courtney; Nguyen, Brenda; Kahle, Joerg; Königs, Christoph; Li, Renhao; Lollar, Pete; Meeks, Shannon L

2016-10-20

Inhibitor formation in hemophilia A is the most feared treatment-related complication of factor VIII (fVIII) therapy. Most inhibitor patients with hemophilia A develop antibodies against the fVIII A2 and C2 domains. Recent evidence demonstrates that the C1 domain contributes to the inhibitor response. Inhibitory anti-C1 monoclonal antibodies (mAbs) have been identified that bind to putative phospholipid and von Willebrand factor (VWF) binding epitopes and block endocytosis of fVIII by antigen presenting cells. We now demonstrate by competitive enzyme-linked immunosorbent assay and hydrogen-deuterium exchange mass spectrometry that 7 of 9 anti-human C1 mAbs tested recognize an epitope distinct from the C1 phospholipid binding site. These mAbs, designated group A, display high binding affinities for fVIII, weakly inhibit fVIII procoagulant activity, poorly inhibit fVIII binding to phospholipid, and exhibit heterogeneity with respect to blocking fVIII binding to VWF. Another mAb, designated group B, inhibits fVIII procoagulant activity, fVIII binding to VWF and phospholipid, fVIIIa incorporation into the intrinsic Xase complex, thrombin generation in plasma, and fVIII uptake by dendritic cells. Group A and B epitopes are distinct from the epitope recognized by the canonical, human-derived inhibitory anti-C1 mAb, KM33, whose epitope overlaps both groups A and B. Antibodies recognizing group A and B epitopes are present in inhibitor plasmas from patients with hemophilia A. Additionally, group A and B mAbs increase fVIII clearance and are pathogenic in a hemophilia A mouse tail snip bleeding model. Group A anti-C1 mAbs represent the first identification of pathogenic, weakly inhibitory antibodies that increase fVIII clearance. © 2016 by The American Society of Hematology.

Overview of platelet physiology and laboratory evaluation of platelet function.

PubMed

Rodgers, G M

1999-06-01

Appropriate laboratory testing for the platelet-type bleeding disorders hinges on an adequate assessment in the history and physical examination. Patients with histories and screening laboratory results consistent with coagulation disorders (hemophilia, disseminated intravascular coagulation) are not appropriate candidates for platelet function testing. In contrast, patients with a lifelong history of platelet-type bleeding symptoms and perhaps a positive family history of bleeding would be appropriate for testing. Figure 6 depicts one strategy to evaluate these patients. Platelet morphology can easily be evaluated to screen for two uncommon qualitative platelet disorders: Bernard-Soulier syndrome (associated with giant platelets) and gray platelet syndrome, a subtype of storage pool disorder in which platelet granulation is morphologically abnormal by light microscopy. If the bleeding disorder occurred later in life (no bleeding with surgery or trauma early in life), the focus should be on acquired disorders of platelet function. For those patients thought to have an inherited disorder, testing for vWD should be done initially because approximately 1% of the population has vWD. The complete vWD panel (factor VIII coagulant activity, vWf antigen, ristocetin cofactor activity) should be performed because many patients will have abnormalities of only one particular panel component. Patients diagnosed with vWD should be classified using multimeric analysis to identify the type 1 vWD patients likely to respond to DDAVP. If vWD studies are normal, platelet aggregation testing should be performed, ensuring that no antiplatelet medications have been ingested at least 1 week before testing. If platelet aggregation tests are normal and if suspicion for an inherited disorder remains high, vWD testing should be repeated. The evaluation of thrombocytopenia may require bone marrow examination to exclude primary hematologic disorders. If future studies with thrombopoietin assays confirm preliminary results, however, the bone marrow examination of certain patients may be replaced by a thrombopoietin level.

Hemodialysis in a patient with severe hemophilia A and factor VIII inhibitor.

PubMed

Gopalakrishnan, Natarajan; Usha, Thiruvengadam; Thopalan, Balasubramaniyan; Dhanapriya, Jeyachandran; Dineshkumar, Thanigachalam; Thirumalvalavan, Kaliaperumal; Sakthirajan, Ramanathan

2016-10-01

Hemophilia A is a hereditary X-linked recessive disease caused by mutations in the gene encoding factor VIII (FVIII), occurring in 1 out of 10,000 persons. Life expectancy and quality of life have dramatically improved recently in patients with hemophilia. Chronic kidney disease and need for renal replacement therapy in these patients are rare. The development of inhibitors to FVIII is the most serious complication of hemophilia and makes treatment of bleeds very challenging. We describe here a 28-year-old male patient with severe hemophilia A with presence of factor VIII inhibitor, who had end stage renal disease. Central venous access device was inserted along with infusion of factor eight inhibitor bypass activity before and after the procedure. He is currently on thrice weekly hemodialysis and doing well for 6 months without bleeding episodes. To our knowledge, hemophilia A with factor VIII inhibitor managed with hemodialysis has not been reported so far. © 2016 International Society for Hemodialysis.

Correction of murine hemophilia A following nonmyeloablative transplantation of hematopoietic stem cells engineered to encode an enhanced human factor VIII variant using a safety-augmented retroviral vector

PubMed Central

Ramezani, Ali

2009-01-01

Insertional mutagenesis by retroviral vectors is a major impediment to the clinical application of hematopoietic stem cell gene transfer for the treatment of hematologic disorders. We recently developed an insulated self-inactivating gammaretroviral vector, RMSinOFB, which uses a novel enhancer-blocking element that significantly decreases genotoxicity of retroviral integration. In this study, we used the RMSinOFB vector to evaluate the efficacy of a newly bioengineered factor VIII (fVIII) variant (efVIII)—containing a combination of A1 domain point mutations (L303E/F309S) and an extended partial B domain for improved secretion plus A2 domain mutations (R484A/R489A/P492A) for reduced immunogenicity—toward successful treatment of murine hemophilia A. In cell lines, efVIII was secreted at up to 6-fold higher levels than an L303E/F309S A1 domain–only fVIII variant (sfVIIIΔB). Most important, when compared with a conventional gammaretroviral vector expressing sfVIIIΔB, lower doses of RMSin-efVIII-OFB–transduced hematopoietic stem cells were needed to generate comparable curative fVIII levels in hemophilia A BALB/c mice after reduced-intensity total body irradiation or nonmyeloablative chemotherapy conditioning regimens. These data suggest that the safety-augmented RMSin-efVIII-OFB platform represents an encouraging step in the development of a clinically appropriate gene addition therapy for hemophilia A. PMID:19470695

Protein C and protein S deficiencies: similarities and differences between two brothers playing in the same game.

PubMed

Bereczky, Zsuzsanna; Kovács, Kitti B; Muszbek, László

2010-12-01

Protein C (PC) and protein S (PS) are vitamin K-dependent glycoproteins that play an important role in the regulation of blood coagulation as natural anticoagulants. PC is activated by thrombin and the resulting activated PC (APC) inactivates membrane-bound activated factor VIII and factor V. The free form of PS is an important cofactor of APC. Deficiencies in these proteins lead to an increased risk of venous thromboembolism; a few reports have also associated these deficiencies with arterial diseases. The degree of risk and the prevalence of PC and PS deficiency among patients with thrombosis and in those in the general population have been examined by several population studies with conflicting results, primarily due to methodological variability. The molecular genetic background of PC and PS deficiencies is heterogeneous. Most of the mutations cause type I deficiency (quantitative disorder). Type II deficiency (dysfunctional molecule) is diagnosed in approximately 5%-15% of cases. The diagnosis of PC and PS deficiencies is challenging; functional tests are influenced by several pre-analytical and analytical factors, and the diagnosis using molecular genetics also has special difficulties. Large gene segment deletions often remain undetected by DNA sequencing methods. The presence of the PS pseudogene makes genetic diagnosis even more complicated.

Diagnosis and management of von Willebrand disease: a developing country perspective.

PubMed

Nair, Sukesh Chandran; Viswabandya, Auro; Srivastava, Alok

2011-07-01

Special challenges exist in the management of patients with von Willebrand disease (VWD) because of limitations in diagnostic facilities and therapeutic options. However, even within these limitations, it is possible to establish comprehensive services for this condition. Our data show that among 202 patients with VWD, 107 were type 3, 62 were type 1, and the others different categories of type 2. Basic tests such as bleeding time and activated partial thromboplastin time with factor (F)VIII coagulant are able to diagnose most of those with severe disease. We have been able to adapt the specific tests such as von Willebrand factor (VWF) ristocetin cofactor and VWF antigen from the tedious batched manual methods to cost-effective automated methods on advanced coagulometers. Discriminatory tests such as VWF collagen binding, VWF:FVIIIB, ristocetin-induced platelet agglutination (RIPA) are done in batches. Therapeutic options and for the treatment of bleeding include desmopressin, cryoprecipitate, and intermediate purity VWF-containing clotting factor concentrates. Tranexamic acid is also widely used as well as hormonal therapy for menorrhagia. We have also shown that modest doses of intermediate purity FVIII (Koate DVI; Talecris Biotherapeutics, Raleigh, NC, USA) at 35 IU/kg preoperatively and 10 to 20 IU/kg after that are sufficient for surgical hemostasis in these patients. © Thieme Medical Publishers.

Report of a factor VIII inhibitor in a patient with autoimmune lymphoproliferative syndrome.

PubMed

Fang, B S; Sneller, M C; Straus, S E; Frenkel, L; Dale, J K; Rick, M E

2000-07-01

The occurrence of factor VIII inhibitors in non-hemophilic patients is a rare event with a potentially lethal outcome. Despite its infrequent occurrence, the association of this inhibitor with multiple autoimmune diseases is well recognized. We report the case of a patient with the recently described autoimmune lymphoproliferative syndrome (ALPS) who developed an inhibitor to factor VIII. ALPS is a disease characterized by defective lymphocyte apoptosis due to inherited mutations in genes that regulate apoptosis, with the resulting enlargement of lymphoid organs and a variety of autoimmune manifestations. Published 2000 Wiley-Liss, Inc.

The new albumin-free recombinant factor VIII concentrates for treatment of hemophilia: do they represent an actual incremental improvement?

PubMed

Josephson, Cassandra D; Abshire, Thomas

2004-07-01

The goal of eliminating the low levels of infectious disease risk from hemophilia treatment has resulted in the development of multiple generations of recombinant factor VIII (rFVIII) products. The ideal product should be devoid of human and animal proteins, which may transmit infectious agents. These products should also maintain molecular integrity, hemostatic efficacy, similar immunogenicity, and acceptable side effect profiles as compared to plasma-derived factor VIII. Currently available first-, second-, and third-generation rFVIII products include Recombinate; Kogenate FS/Helixate FS and ReFacto; and Advate, respectively. During the evolution of rFVIII products, either full-length or B-domain-deleted factor VIII were transfected into immortalized cell lines. The B-domain-deleted product, ReFacto, has resulted in an additional method to monitor factor VIII levels. The third-generation products offer the theoretical advantage of being produced without human and/or animal proteins. Upon initial introduction into the marketplace, the newer products have a higher cost. However, when analyzing historical trends, the prices of these products are almost equivalent to first-generation products within 3 years of licensure. Thus, the initial cost of the product may be a minimal issue in the medical decision process when selecting rFVIII replacement therapy.

Plasma temperature during methylene blue/light treatment influences virus inactivation capacity and product quality.

PubMed

Gravemann, U; Handke, W; Sumian, C; Alvarez, I; Reichenberg, S; Müller, T H; Seltsam, A

2018-02-27

Photodynamic treatment using methylene blue (MB) and visible light is in routine use for pathogen inactivation of human plasma in different countries. Ambient and product temperature conditions for human plasma during production may vary between production sites. The influence of different temperature conditions on virus inactivation capacity and plasma quality of the THERAFLEX MB-Plasma procedure was investigated in this study. Plasma units equilibrated to 5 ± 2°C, room temperature (22 ± 2°C) or 30 ± 2°C were treated with MB/light and comparatively assessed for the inactivation capacity for three different viruses, concentrations of MB and its photoproducts, activity of various plasma coagulation factors and clotting time. Reduced solubility of the MB pill was observed at 5 ± 2°C. Photocatalytic degradation of MB increased with increasing temperature, and the greatest formation of photoproducts (mainly azure B) occurred at 30 ± 2°C. Inactivation of suid herpesvirus, bovine viral diarrhoea virus and vesicular stomatitis virus was significantly lower at 5 ± 2°C than at higher temperatures. MB/light treatment affected clotting times and the activity of almost all investigated plasma proteins. Factor VIII (-17·7 ± 8·3%, 22 ± 2°C) and fibrinogen (-14·4 ± 16·4%, 22 ± 2°C) showed the highest decreases in activity. Increasing plasma temperatures resulted in greater changes in clotting time and higher losses of plasma coagulation factor activity. Temperature conditions for THERAFLEX MB-Plasma treatment must be carefully controlled to assure uniform quality of pathogen-reduced plasma in routine production. Inactivation of cooled plasma is not recommended. © 2018 International Society of Blood Transfusion.

Successful Pregnancy in a Patient with Combined Deficiency of Factor V and Factor VIII.

PubMed

El Adib, Ahmed Ghassan; Majdi, Farah; Dilai, Mohamed Othmane; Asmouki, Hamid; Bassir, Ahlam; Harou, Karam; Soumani, Abderraouf; Younous, Said; Mahmal, Lahoucine

2014-01-01

Inherited combined factor V and factor VIII deficiency (F5F8D) is autosomal recessive transmission disorder. Epistaxis, postsurgical bleeding, and menorrhagia are the most common symptoms. The risk of miscarriage and placental abruption is consequent. We report a case of successful pregnancy in a patient with F5F8D. 20-year-old woman, born of consanguineous parents, third gestate, first parity, two miscarriages, admitted for child birth of a spontaneous pregnancy estimated at 38 weeks and was diagnosed with F5F8D. At admission, patient was hemodynamically stable, with good obstetric conditions. The biologic results showed low levels of PT (52%), factor V (7%), and factor VIII (5%), and the activated partial thromboplastin time was prolonged (68,6%). Parturient was admitted in intensive care unit, maternal and fetal monitoring was performed. Fresh frozen plasma (FFP) and factor VIII concentrates were perfused at the induction of labor. Analgesia used fentanyl titration. The delivery gave birth to a newborn male, with Apgar 10/10 and 3000 g. The puerperium was simple without any important bleeding. Laboratory tests for the newborn were acceptable. Little literature is available on this subject and there are no guidelines available concerning pregnancy; we chose to prescribe a combination of factor VIII concentrate and FFP in pre-, per- and postpartum. The same protocol was successfully used in a patient before dental extraction and prostatectomy. Vaginal delivery is possible, as our case. Management by multidisciplinary team is recommended.

Effect of Hemodilution on Coagulation and Recombinant Factor VIIa Efficacy in Human Blood In Vitro

DTIC Science & Technology

2011-11-01

thrombasthenia.12 In trauma, when a blood vessel is injured, tissue factor on subendothelial pericytes is exposed and binds to endogenous FVII ...a more complex effect on coagulation than simply dilution of any single coagulation factor like FVII or fibrinogen (Fig. 1). It is interesting to note...ORIGINAL ARTICLE Effect of Hemodilution on Coagulation and Recombinant Factor VIIa Efficacy in Human Blood In Vitro Daniel N. Darlington, PhD, Angel

[Coagulation factor VII levels in uremic patients and theirs influence factors].

PubMed

Fang, Jun; Xia, Ling-Hui; Wei, Wen-Ning; Song, Shan-Jun

2004-12-01

This study was aimed to investigate coagulation factor VII level in uremic patients with chronic renal failure and to explore theirs influence factors. The plasma levels of coagulation factor VII were detected in 30 uremic patients with chronic renal failure before and after hemodialysis for 1 month, the factor VII activity (FVII:C) was determined by one-stage coagulation method, while activated factor VII (FVIIa) was measured by one-stage coagulation method using recombinant soluble tissue factor, and factor VII antigen was detected by ELISA. The results showed that: (1) The FVIIa, FVII:C and FVIIAg levels in chronic uremic patients before hemodialysis were 4.00 +/- 0.86 microg/L, (148.5 +/- 40.4)% and (99.8 +/- 21.1)% respectively, which were significantly increased, as compared with healthy controls [2.77 +/- 1.02 microg/L, (113.1 +/- 33.0)% and (73.7 +/- 18.3)% respectively, P < 0.05]. (2) After hemodialysis the FVIIa, FVII:C and FVIIAg levels in uremic patients significantly enhanced to 5.56 +/- 1.45 microg/L, (200.8 +/- 68.7)% and (124.1 +/- 19.3)% respectively (P < 0.05). (3) The abnormal increase of coagulation factor VII was positively correlated with levels of blood uria nitrogen and serum creatinine before hemodialysis but not after hemodialysis. It is concluded that the enhanced levels of coagulation factor VII in chronic uremic patients suggested abnormal activated state, herperactivity and elevated production of factor VII which correlated with renal functional injury. The abnormality of factor VII in uremia may be aggravated by hemodialysis. Coagulation factor (FVII) may be a risk factor for cardiovascular events in uremic patients who especially had been accepted long-term hemodialysis.

Efficacy and safety of rVIII-SingleChain: results of a phase 1/3 multicenter clinical trial in severe hemophilia A.

PubMed

Mahlangu, Johnny; Kuliczkowski, Kazimierz; Karim, Faraizah Abdul; Stasyshyn, Oleksandra; Kosinova, Marina V; Lepatan, Lynda Mae; Skotnicki, Aleksander; Boggio, Lisa N; Klamroth, Robert; Oldenburg, Johannes; Hellmann, Andrzej; Santagostino, Elena; Baker, Ross I; Fischer, Kathelijn; Gill, Joan C; P'Ng, Stephanie; Chowdary, Pratima; Escobar, Miguel A; Khayat, Claudia Djambas; Rusen, Luminita; Bensen-Kennedy, Debra; Blackman, Nicole; Limsakun, Tharin; Veldman, Alex; St Ledger, Katie; Pabinger, Ingrid

2016-08-04

Recombinant VIII (rVIII)-SingleChain is a novel B-domain-truncated recombinant factor VIII (rFVIII), comprised of covalently bonded factor VIII (FVIII) heavy and light chains. It was designed to have a higher binding affinity for von Willebrand factor (VWF). This phase 1/3 study investigated the efficacy and safety of rVIII-SingleChain in the treatment of bleeding episodes, routine prophylaxis, and surgical prophylaxis. Participants were ≥12 years of age, with severe hemophilia A (endogenous FVIII <1%). The participants were allocated by the investigator to receive rVIII-SingleChain in either an on-demand or prophylaxis regimen. Of the 175 patients meeting study eligibility criteria, 173 were treated with rVIII-SingleChain, prophylactically (N = 146) or on-demand (N = 27). The total cumulative exposure was 14 306 exposure days (EDs), with 120 participants reaching ≥50 EDs and 52 participants having ≥100 EDs. Hemostatic efficacy was rated by the investigator as excellent or good in 93.8% of the 835 bleeds treated and assessed. Across all prophylaxis regimens, the median annualized spontaneous bleeding rate was 0.00 (Q1, Q3: 0.0, 2.4) and the median overall annualized bleeding rate (ABR) was 1.14 (Q1, Q3: 0.0, 4.2). Surgical hemostasis was rated as excellent/good in 100% of major surgeries by the investigator. No participant developed FVIII inhibitors. In conclusion, rVIII-SingleChain is a novel rFVIII molecule showing excellent hemostatic efficacy in surgery and in the control of bleeding events, low ABR in patients on prophylaxis, and a favorable safety profile in this large clinical study. This trial was registered at www.clinicaltrials.gov as #NCT01486927. © 2016 by The American Society of Hematology.

Acquired high titre factor VIII inhibitor with underlying polyarteritis nodosa.

PubMed

Snowden, J A; Hutchings, M; Spearing, R; Patton, W N

1997-05-01

We here present the case of a 70-year-old woman referred to our unit for investigation of bleeding. Investigations confirmed a high titre acquired Factor VIII inhibitor. In association there was relapse of systemic illness associated with anti-neutrophil cytoplasmic antibodies (atypical pattern) for which she had been treated five years previously. Immunosuppression was attempted, but it failed to have an impact both on the inhibitor titre and on the underlying disorder. The patient died from multi-organ failure and massive chest hemorrhage. Post-mortem showed necrotizing vasculitis of medium sized vessels at several sites, including the kidney, consistent with a diagnosis of polyarteritis nodosa. Although it is well recognised that Factor VIII inhibitors are found in conjunction with autoimmune disorders, this case is significant in that it is the first associated with histologically proven polyarteritis nodosa type vasculitis. The case illustrates the difficulties in the investigation and management of patients with acquired high titre Factor VIII inhibitors.

Rare and low-frequency variants and their association with plasma levels of fibrinogen, FVII, FVIII, and vWF

PubMed Central

Huffman, Jennifer E.; de Vries, Paul S.; Morrison, Alanna C.; Sabater-Lleal, Maria; Kacprowski, Tim; Auer, Paul L.; Brody, Jennifer A.; Chasman, Daniel I.; Chen, Ming-Huei; Guo, Xiuqing; Lin, Li-An; Marioni, Riccardo E.; Müller-Nurasyid, Martina; Yanek, Lisa R.; Pankratz, Nathan; Grove, Megan L.; de Maat, Moniek P. M.; Cushman, Mary; Wiggins, Kerri L.; Qi, Lihong; Sennblad, Bengt; Harris, Sarah E.; Polasek, Ozren; Riess, Helene; Rivadeneira, Fernando; Rose, Lynda M.; Goel, Anuj; Taylor, Kent D.; Teumer, Alexander; Uitterlinden, André G.; Vaidya, Dhananjay; Yao, Jie; Tang, Weihong; Levy, Daniel; Waldenberger, Melanie; Becker, Diane M.; Folsom, Aaron R.; Giulianini, Franco; Greinacher, Andreas; Hofman, Albert; Huang, Chiang-Ching; Kooperberg, Charles; Silveira, Angela; Starr, John M.; Strauch, Konstantin; Strawbridge, Rona J.; Wright, Alan F.; McKnight, Barbara; Franco, Oscar H.; Zakai, Neil; Mathias, Rasika A.; Psaty, Bruce M.; Ridker, Paul M.; Tofler, Geoffrey H.; Völker, Uwe; Watkins, Hugh; Fornage, Myriam; Hamsten, Anders; Deary, Ian J.; Boerwinkle, Eric; Koenig, Wolfgang; Rotter, Jerome I.; Hayward, Caroline; Dehghan, Abbas; Reiner, Alex P.; O’Donnell, Christopher J.

2015-01-01

Fibrinogen, coagulation factor VII (FVII), and factor VIII (FVIII) and its carrier von Willebrand factor (vWF) play key roles in hemostasis. Previously identified common variants explain only a small fraction of the trait heritabilities, and additional variations may be explained by associations with rarer variants with larger effects. The aim of this study was to identify low-frequency (minor allele frequency [MAF] ≥0.01 and <0.05) and rare (MAF <0.01) variants that influence plasma concentrations of these 4 hemostatic factors by meta-analyzing exome chip data from up to 76 000 participants of 4 ancestries. We identified 12 novel associations of low-frequency (n = 2) and rare (n = 10) variants across the fibrinogen, FVII, FVIII, and vWF traits that were independent of previously identified associations. Novel loci were found within previously reported genes and had effect sizes much larger than and independent of previously identified common variants. In addition, associations at KCNT1, HID1, and KATNB1 identified new candidate genes related to hemostasis for follow-up replication and functional genomic analysis. Newly identified low-frequency and rare-variant associations accounted for modest amounts of trait variance and therefore are unlikely to increase predicted trait heritability but provide new information for understanding individual variation in hemostasis pathways. PMID:26105150

Contributions of phosphatidylserine-positive platelets and leukocytes and microparticles to hypercoagulable state in gastric cancer patients.

PubMed

Yang, Chunfa; Ma, Ruishuang; Jiang, Tao; Cao, Muhua; Zhao, Liangliang; Bi, Yayan; Kou, Junjie; Shi, Jialan; Zou, Xiaoming

2016-06-01

Hypercoagulability in gastric cancer is a common complication and a major contributor to poor prognosis. This study aimed to determine procoagulant activity of blood cells and microparticles (MPs) in gastric cancer patients. Phosphatidylserine-positive blood cells and MPs, and their procoagulant properties in particular, were assessed in 48 gastric cancer patients and 35 healthy controls. Phosphatidylserine-positive platelets, leukocytes, and MPs in patients with tumor-node-metastasis stage III/IV gastric cancer were significantly higher than those in stage I/II patients or healthy controls. Moreover, procoagulant activity of platelets, leukocytes, and MPs in stage III/IV patients was significantly increased compared to the controls, as indicated by shorter clotting time, higher intrinsic and extrinsic factor tenase, and prothrombinase complex activity. Interestingly, lactadherin, which competes with factors V and VIII to bind phosphatidylserine, dramatically prolonged clotting time of the cells and MPs by inhibiting factor tenase and prothrombinase complex activity. Although anti-tissue factor antibody significantly attenuated extrinsic tenase complex activity of leukocytes and MPs, it only slightly prolonged clotting times. Meanwhile, treatment with radical resection reduced phosphatidylserine-positive platelets, leukocytes, and MPs, and prolonged the clotting times of the remaining cells and MPs. Our results suggest that phosphatidylserine-positive platelets, leukocytes, and MPs contribute to hypercoagulability and represent a potential therapeutic target to prevent coagulation in patients with stage III/IV gastric cancer.

Lupus anticoagulant, anticardiolipin antibodies, and human immunodeficiency virus in haemophilia.

PubMed Central

Cohen, H; Mackie, I J; Anagnostopoulos, N; Savage, G F; Machin, S J

1989-01-01

The prevalence of lupus anticoagulant, using the dilute Russell's viper venom time (DRVT), was determined in 22 patients with mild to severe haemophilia A to see if there was any association with the presence of viral disease. Twelve haemophiliacs (58%) were lupus anticoagulant positive, with a mean patient:control ratio of 1.24 (range 1.15-1.52, normal range 0.84-1.06 which partially corrected with lysed, washed platelets). Nine of these patients were IgG or IgM, or both, anticardiolipin antibody positive and nine were human immunodeficiency virus (HIV) antibody positive, but associations between lupus anticoagulant, anticardiolipin antibodies, and HIV antibody positivity were not significant. Mixing studies of normal plasma and immune depleted factor VIII deficient plasma showed that the DRVT ratio increased when the factor VIII concentration fell below 0.15 IU/ml. There was no significant association between plasma factor VIII concentration and positive DRVT results in haemophiliacs. The addition of porcine factor VIII concentrate produced no correction in eight of the 12 with DRVTs indicative of lupus anticoagulant, suggesting that these were prolonged by antiphospholipid activity. It is concluded that the presence of lupus anticoagulant and anticardiolipin antibodies in haemophiliacs may represent an antiphospholipid response to viraemic challenge, not only to HIV but also to other viral antigens, and that a very low factor VIII concentration may produce a false positive DRVT result. PMID:2500459

Competition of coagulation sink and source rate: New particle formation in the Pearl River Delta of China

NASA Astrophysics Data System (ADS)

Gong, Youguo; Hu, Min; Cheng, Yafang; Su, Hang; Yue, Dingli; Liu, Feng; Wiedensohler, A.; Wang, Zhibin; Kalesse, H.; Liu, Shang; Wu, Zhijun; Xiao, Kaitao; Mi, Puchun; Zhang, Yuanhang

The coagulation sink and its role in new particle formation are investigated based on data obtained during the PRIDE-PRD2004 campaign at Xinken of Pearl River Delta, China. Analysis of size distributions and mode contributions of the coagulation sink show that the observed higher load of accumulation mode particles impose a significant effect on the coagulation sink and result in higher coagulation sinks at Xinken despite of the lower total particle number compared with other areas. Hence it is concluded that the higher coagulation sink may depress the occurrence frequency of new particle formation events. The strategies targeting at controlling accumulation mode particles may have influences on the frequency of new particle formation events at this area. The factors affecting the coagulation sink are evaluated. The relatively lower ambient relative humidities may weaken the coagulation sink and facilitate the occurrence of new particle formation events during noontime, while the surmise of nucleation and growth involving organic matter may imply an actually higher coagulation sink than expected. These factors have a significant influence on the ultimate fate of the newly formed nuclei and new particle formation. A comparison of event and non-event days indicates that the coagulation sink is not the only decisive factor affecting new particle formation, other factors including the precursor vapors and photochemical activity are none the less important either. Competition of coagulation sink and high source rate leads to the occurrence of new particle formation events at Xinken.

The effect of prothrombotic blood abnormalities on risk of deep vein thrombosis in users of hormone replacement therapy: a prospective case-control study.

PubMed

Douketis, Jim D; Julian, Jim A; Crowther, Mark A; Kearon, Clive; Bates, Shannon M; Barone, Marisa; Piovella, Franco; Middeldorp, Saskia; Prandoni, Paolo; Johnston, Marilyn; Costantini, Lorrie; Ginsberg, Jeffrey S

2011-01-01

Few studies have assessed the effect of prothrombotic blood abnormalities on the risk of deep vein thrombosis (DVT) with hormone replacement therapy (HRT). We studied postmenopausal women with suspected DVT in whom HRT use and prothrombotic blood abnormalities were sought. Cases had unprovoked DVT and controls had no DVT and without DVT risk factors. The risk of DVT was determined in women with and without prothrombotic abnormalities. A total of 510 postmenopausal women with suspected DVT were assessed; 57 cases and 283 controls were identified. Compared to HRT, nonusers without the factor V Leiden mutation, the risk of DVT was increased in estrogen-progestin HRT users (odds ratio [OR], 3.2; 95% confidence interval [CI]: 1.2-8.6) and in nonusers with the factor V Leiden mutation (OR, 5.3; 1.9-15.4) and appears multiplied in users of estrogen-progestin HRT with the factor V Leiden mutation (OR, 17.1; 3.7-78). Compared to HRT, nonusers with normal factor VIII, the risk of DVT was increased in estrogen-progestin HRT users with normal factor VIII (OR, 2.8; 1.0-7.9) and in HRT nonusers with the highest factor VIII quartile (OR, 6.0; 2.1-17), and appears to be multiplied in women who are users of estrogen-progestin HRT with the highest factor VIII quartile (OR, 17.0; 3.6-80). In postmenopausal women who are estrogen-progestin HRT users, the presence of the factor V Leiden mutation or an elevated factor VIII level appears to have a multiplicative effect on their overall risk of DVT, increasing it 17-fold compared to women without these blood abnormalities who are HRT nonusers.

Factor VIII-associated antigen in human lymphatic endothelium.

PubMed

Nagle, R B; Witte, M H; Martinez, A P; Witte, C L; Hendrix, M J; Way, D; Reed, K

1987-03-01

Lymphatic vascular endothelium both on tissue section and in culture exhibits positivity for Factor VIII-associated antigen although staining is generally less intense and more spotty than in comparable blood vascular endothelium. Lymphatic endothelium also exhibits Weibel-Palade bodies. Neither marker, therefore, reliably distinguishes blood vascular endothelium from lymphatic endothelium.

[Remission of acquired hemophilia A following radiation therapy for esophageal cancer].

PubMed

Yanagisawa, Kunio; Ogawa, Yoshiyuki; Mitsui, Takeki; Noguchi, Hiroyuki; Shimizu, Hiroaki; Ishizaki, Takuma; Handa, Hiroshi; Ieko, Masahiro; Ichinose, Akitada; Nojima, Yoshihisa

2016-04-01

Although acquired hemophilia A (AHA) often develops in patients with neoplasms, there are few reports on the efficacy of radiation therapy during the bleeding phase of AHA in the prior literature. We herein present a case of AHA experiencing remission soon after radiation therapy for esophageal cancer. A man in his seventies, who had a history of radical nephrectomy for left renal cell carcinoma, received a diagnosis of esophageal cancer. Three months later, he noticed a right thigh hematoma, and was transferred to our hospital. Laboratory data revealed a marked reduction of coagulation factor VIII (FVIII) activity at 0.9% and the inhibitor to FVIII was detected in his serum at 21.8 BU/ml. Under a diagnosis of AHA, the patient received high-dose oral prednisolone, which failed to achieve disease remission. He then underwent radiation therapy to eradicate the underlying esophageal cancer. Despite tapering of the prednisolone dosage, FVIII inhibitor declined to undetectable levels. In this case, radiation therapy for the underlying cancer was associated with achieving complete remission of AHA.

Home therapy with continuous infusion of factor VIII after minor surgery or serious haemorrhage.

PubMed

Varon, D; Schulman, S; Bashari, D; Martinowitz, U

1996-10-01

Administration of factor VIII (F VIII) concentrates by continuous infusion is now routinely used at several haemophilia centers but almost exclusively for hospitalized patients. We evaluated various aspects of home therapy with continuous infusion of an immunoaffinity purified F VIII concentrate (Monoclate P®, Armour) in patients who would normally have been treated with high doses in bolus injections or with continuous infusion as in-patients. Twenty haemophilia A patients, eight after minor surgery and 12 for serious haemorrhage, received continuous infusion with undiluted F VIII by a minipump for a mean of 0.9 days in the hospital, followed by 3.3 days at home. Infusion bags were exchanged every 2.5 days. No haemorrhagic complications occurred, and five haemorrhages that had been resistant to treatment with bolus injections responded promptly to the continuous infusion. There were no technical problems and patient compliance and acceptance was good. We find this mode of therapy safe, efficacious and convenient for the patients as well as for the staff.

A close insight to factor VIII inhibitor in the congenital hemophilia A.

PubMed

Tabriznia-Tabrizi, Shamsoreza; Gholampour, Marzie; Mansouritorghabeh, Hassan

2016-09-01

Hemophilia A (HA) has an X-linked pattern of inheritance and is the most common of the hemorrhagic disorders. HA is caused by a decreased or deficiency of the functional clotting factor VIII (FVIII) and effects 1 in 5000-10,000 male births. The common treatment for hemophilia is replacement therapy by plasma-derived or recombinant FVIII. Approximately 20-30% of people with a severe type of HA develop an inhibitor and this phenomenon is the main challenge in the management of these patients. Genetic factors and environmental determinants contribute to inhibitor development. Here, the roles of various genetic and environmental factors such as the type of FVIII concentrate used, the number of exposure days, and peak treatment time will be discussed in detail. It seems this information is helpful for hematologists. A literature review was done in January 2016 on PubMed and Scopus using the following keywords:' h(a)emophilia A & factor VIII inhibitor', 'h(a)emophilia A & factor VIII alloantibody', 'h(a)emophilia A & inhibitor'. There was no time limitation; however, there was an English language limitation placed on the articles selected. Expert commentary: Influential genetic and environmental factors in developing inhibitors have been discussed. Most of the risk factors are related to previously untreated patients with hemophili.

Protein corona changes mediated by surface modification of amorphous silica nanoparticles suppress acute toxicity and activation of intrinsic coagulation cascade in mice

NASA Astrophysics Data System (ADS)

Yoshida, Tokuyuki; Yoshioka, Yasuo; Morishita, Yuki; Aoyama, Michihiko; Tochigi, Saeko; Hirai, Toshiro; Tanaka, Kota; Nagano, Kazuya; Kamada, Haruhiko; Tsunoda, Shin-ichi; Nabeshi, Hiromi; Yoshikawa, Tomoaki; Higashisaka, Kazuma; Tsutsumi, Yasuo

2015-06-01

Recently, nanomaterial-mediated biological effects have been shown to be governed by the interaction of nanomaterials with some kinds of proteins in biological fluids, and the physical characteristics of the nanomaterials determine the extent and type of their interactions with proteins. Here, we examined the relationships between the surface properties of amorphous silica nanoparticles with diameters of 70 nm (nSP70), their interactions with some proteins in biological fluids, and their toxicity in mice after intravenous administration. The surface modification of nSP70 with amino groups (nSP70-N) prevented acute lethality and abnormal activation of the coagulation cascade found in the nSP70-treated group of mice. Since our previous study showed that coagulation factor XII played a role in the nSP70-mediated abnormal activation of the coagulation cascade, we examined the interaction of nSP70 and nSP70-N with coagulation factor XII. Coagulation factor XII bonded to the surface of nSP70 to a greater extent than that observed for nSP70-N, and consequently more activation of coagulation factor XII was observed for nSP70 than for nSP70-N. Collectively, our results suggest that controlling the interaction of nSP70 with blood coagulation factor XII by modifying the surface properties would help to inhibit the nSP70-mediated abnormal activation of the blood coagulation cascade.

Haemophilia A: carrier detection and prenatal diagnosis by linkage analysis using DNA polymorphism.

PubMed Central

Tuddenham, E G; Goldman, E; McGraw, A; Kernoff, P B

1987-01-01

Restriction fragment length polymorphisms (RFLPs) within or close to the factor VIII locus are very useful for genetic linkage analysis. Such RFLPs allow a mutant allele to be tracked in a family, segregating haemophilia A even when, as is usually the case, the precise mutation causing failure to synthesise factor VIII is unknown. To date two markers tightly linked to the factor VIII locus have been described, one of which is highly polymorphic and therefore informative in most kindreds. A significant crossover rate, however, does not make diagnosis absolute. Three intragenic RFLPs have been defined, which, taken together, are informative in about 70% of women, providing virtually deterministic genetic diagnosis. PMID:2889753

Differential roles of tissue factor and phosphatidylserine in activation of coagulation.

PubMed

Spronk, Henri M H; ten Cate, Hugo; van der Meijden, Paola E J

2014-05-01

It has been suggested that the main physiological trigger of coagulation, tissue factor, possesses limited procoagulant activity and occurs in an inactive or so-called encrypted state. For the conversion of encrypted into decrypted tissue factor with sufficient procoagulant activity, four distinct models have been proposed: 1; dimer formation, 2; lipid rafts, 3; disulfide bonds, and 4; phosphatidylserine exposure. Pro and cons can be given for each of these mechanisms of tissue factor encryption/decryption, however, it seems most likely that two or more mechanisms act together in activating the procoagulant activity. The exposure of phosphatidylserine in the outer layer of cell membranes supports coagulation through enhanced formation of the tenase (factors IXa, VIIIa and X) and prothrombinase (factors Xa, Va and prothrombin) complexes. The proposed role for phosphatidylserine in decryption of tissue factor could contribute to the correct orientation of the tissue factor - factor VII complex. Overall, the contribution of both tissue factor and phosphatidylserine to coagulation seems distinct with tissue factor being the physiological activator and phosphatidylserine the driving force of propagation of coagulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Reciprocal coupling of coagulation and innate immunity via neutrophil serine proteases.

PubMed

Massberg, Steffen; Grahl, Lenka; von Bruehl, Marie-Luise; Manukyan, Davit; Pfeiler, Susanne; Goosmann, Christian; Brinkmann, Volker; Lorenz, Michael; Bidzhekov, Kiril; Khandagale, Avinash B; Konrad, Ildiko; Kennerknecht, Elisabeth; Reges, Katja; Holdenrieder, Stefan; Braun, Siegmund; Reinhardt, Christoph; Spannagl, Michael; Preissner, Klaus T; Engelmann, Bernd

2010-08-01

Blood neutrophils provide the first line of defense against pathogens but have also been implicated in thrombotic processes. This dual function of neutrophils could reflect an evolutionarily conserved association between blood coagulation and antimicrobial defense, although the molecular determinants and in vivo significance of this association remain unclear. Here we show that major microbicidal effectors of neutrophils, the serine proteases neutrophil elastase and cathepsin G, together with externalized nucleosomes, promote coagulation and intravascular thrombus growth in vivo. The serine proteases and extracellular nucleosomes enhance tissue factor- and factor XII-dependent coagulation in a process involving local proteolysis of the coagulation suppressor tissue factor pathway inhibitor. During systemic infection, activation of coagulation fosters compartmentalization of bacteria in liver microvessels and reduces bacterial invasion into tissue. In the absence of a pathogen challenge, neutrophil-derived serine proteases and nucleosomes can contribute to large-vessel thrombosis, the main trigger of myocardial infarction and stroke. The ability of coagulation to suppress pathogen dissemination indicates that microvessel thrombosis represents a physiological tool of host defense.

Characterization of a genetically engineered mouse model of hemophilia A with complete deletion of the F8 gene.

PubMed

Chao, B N; Baldwin, W H; Healey, J F; Parker, E T; Shafer-Weaver, K; Cox, C; Jiang, P; Kanellopoulou, C; Lollar, P; Meeks, S L; Lenardo, M J

2016-02-01

ESSENTIALS: Anti-factor VIII (FVIII) inhibitory antibody formation is a severe complication in hemophilia A therapy. We genetically engineered and characterized a mouse model with complete deletion of the F8 coding region. F8(TKO) mice exhibit severe hemophilia, express no detectable F8 mRNA, and produce FVIII inhibitors. The defined background and lack of FVIII in F8(TKO) mice will aid in studying FVIII inhibitor formation. The most important complication in hemophilia A treatment is the development of inhibitory anti-Factor VIII (FVIII) antibodies in patients after FVIII therapy. Patients with severe hemophilia who express no endogenous FVIII (i.e. cross-reacting material, CRM) have the greatest incidence of inhibitor formation. However, current mouse models of severe hemophilia A produce low levels of truncated FVIII. The lack of a corresponding mouse model hampers the study of inhibitor formation in the complete absence of FVIII protein. We aimed to generate and characterize a novel mouse model of severe hemophilia A (designated the F8(TKO) strain) lacking the complete coding sequence of F8 and any FVIII CRM. Mice were created on a C57BL/6 background using Cre-Lox recombination and characterized using in vivo bleeding assays, measurement of FVIII activity by coagulation and chromogenic assays, and anti-FVIII antibody production using ELISA. All F8 exonic coding regions were deleted from the genome and no F8 mRNA was detected in F8(TKO) mice. The bleeding phenotype of F8(TKO) mice was comparable to E16 mice by measurements of factor activity and tail snip assay. Similar levels of anti-FVIII antibody titers after recombinant FVIII injections were observed between F8(TKO) and E16 mice. We describe a new C57BL/6 mouse model for severe hemophilia A patients lacking CRM. These mice can be directly bred to the many C57BL/6 strains of genetically engineered mice, which is valuable for studying the impact of a wide variety of genes on FVIII inhibitor formation on a defined genetic background. © 2015 International Society on Thrombosis and Haemostasis.

Relationship between haemophilia and social status.

PubMed

Holstein, Katharina; Eifrig, Barbara; Langer, Florian

2014-11-01

The impact of haemophilia and its treatment on social status has not been well studied, although research into the quality of life of patients with haemophilia has shed some light on aspects of social and role functioning. Studies conducted before the advent of safe and effective coagulation factor replacement therapy suggest that the haemophilia population was predominantly of low socioeconomic status with many social disadvantages, including high rates of disability and unemployment and low rates of marriage. Since the availability of purified factor VIII concentrates that could be used in a home-care setting and as prophylaxis, most research suggests that social status and well-being amongst children, adolescents, and adults with haemophilia is not compromised, and is comparable to that of the general population. Children and adolescents with haemophilia do not generally feel disadvantaged, although haemophilia-related issues at school and amongst peer groups do arise. Recent studies in adults show higher than average rates of marriage and cohabitation and the attainment of a generally good educational status, but, as in the past, employment rates remain comparatively lower. Social status amongst the elderly with haemophilia who may have developed severe disability as a result of their condition is poorly defined and has never been formally studied. Additional research is recommended. © 2013.

Endothelial cell markers in vascular neoplasms: an immunohistochemical study comparing factor VIII-related antigen, blood group specific antigens, 6-keto-PGF1 alpha, and Ulex europaeus 1 lectin.

PubMed

Little, D; Said, J W; Siegel, R J; Fealy, M; Fishbein, M C

1986-06-01

Markers for endothelial cells including Ulex europaeus 1 lectin, blood group A, B, and H, and the prostaglandin metabolite 6-keto-PGF1 alpha were evaluated in paraffin secretions from formalin-fixed benign and malignant vascular neoplasms using a variety of immunohistochemical techniques, and results compared with staining for factor VIII-related antigen. Staining for Ulex appeared more sensitive than factor VIII-related antigen in identifying poorly differentiated neoplasms including haemangiosarcomas and spindle cell proliferations in Kaposi's sarcoma. Staining for blood group related antigens correlated with blood group in all cases. Ulex europaeus 1 lectin was the only marker for endothelial cells in lymphangiomas.

An in vitro study of the effects of t-PA and tranexamic acid on whole blood coagulation and fibrinolysis.

PubMed

Godier, Anne; Parmar, Kiran; Manandhar, Karuna; Hunt, Beverley J

2017-02-01

Acute traumatic coagulopathy is characterised by fibrinolysis and low fibrinogen. It is unclear how much fibrinogenolysis contributes to reduce fibrinogen levels. The study aim was to: investigate in vitro the effects of tissue-plasminogen activator (t-PA) and tranexamic acid (TXA) on coagulation and fibrinolysis. Whole blood was spiked with varying t-PA concentrations. Clauss fibrinogen levels and thrombelastography (TEG, Haemonetics) were performed, including functional fibrinogen level (FLEV). TXA effects were assessed using four TXA concentrations. Recorded parameters from kaolin activated TEG included maximal amplitude (MA), clot strength (G), percentage lysis (LY). Plasmin-antiplasmin complex (PAP), endogenous thrombin potential (ETP), prothrombin fragment 1+2 (PF1+2), factor V and factor VIII levels were all measured. t-PA induced fibrinolysis: it increased PAP and LY, but decreased MA and G. t-PA induced fibrinogenolysis, with a concentration-dependant decrease in fibrinogen from 2.7 (2.6-3.1) to 0.8 (0.8-0.9) g/L with 60 nM t-PA. FLEV and fibrinogen levels were well correlated. High t-PA doses increased PF1+2, decreased ETP of 19% and FVIII of 63% but not FV. TXA had no effect on plasmin generation as evidenced by no change in PAP. It corrected LY, MA and G and partly protected fibrinogen against fibrinogenolysis: 0.03 mg/mL TXA reduced the fibrinogen fall induced by t-PA 20 nM from 43% to 14%. TXA halved the FVIII fall and increased ETP. t-PA induced plasminogen activation and fibrinogenolysis in a concentration-dependant manner. TXA did not affect plasmin activation but reduced fibrinogenolysis. These results suggest that TXA given early in bleeding patients may prevent fibrinogenolysis. 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/.

Plasma and Plasma Protein Product Transfusion: A Canadian Blood Services Centre for Innovation Symposium.

PubMed

Zeller, Michelle P; Al-Habsi, Khalid S; Golder, Mia; Walsh, Geraldine M; Sheffield, William P

2015-07-01

Plasma obtained via whole blood donation processing or via apheresis technology can either be transfused directly to patients or pooled and fractionated into plasma protein products that are concentrates of 1 or more purified plasma protein. The evidence base supporting clinical efficacy in most of the indications for which plasma is transfused is weak, whereas high-quality evidence supports the efficacy of plasma protein products in at least some of the clinical settings in which they are used. Transfusable plasma utilization remains composed in part of applications that fall outside of clinical practice guidelines. Plasma contains all of the soluble coagulation factors and is frequently transfused in efforts to restore or reinforce patient hemostasis. The biochemical complexities of coagulation have in recent years been rationalized in newer cell-based models that supplement the cascade hypothesis. Efforts to normalize widely used clinical hemostasis screening test values by plasma transfusion are thought to be misplaced, but superior rapid tests have been slow to emerge. The advent of non-vitamin K-dependent oral anticoagulants has brought new challenges to clinical laboratories in plasma testing and to clinicians needing to reverse non-vitamin K-dependent oral anticoagulants urgently. Current plasma-related controversies include prophylactic plasma transfusion before invasive procedures, plasma vs prothrombin complex concentrates for urgent warfarin reversal, and the utility of increased ratios of plasma to red blood cell units transfused in massive transfusion protocols. The first recombinant plasma protein products to reach the clinic were recombinant hemophilia treatment products, and these donor-free equivalents to factors VIII and IX are now being supplemented with novel products whose circulatory half-lives have been increased by chemical modification or genetic fusion. Achieving optimal plasma utilization is an ongoing challenge in the interconnected worlds of transfusable plasma, plasma protein products, and recombinant and engineered replacements. Copyright © 2015 Elsevier Inc. All rights reserved.

Spotlight on the human factor: building a foundation for the future of haemophilia A management: report from a symposium on human recombinant FVIII at the World Federation of Hemophilia World Congress, Melbourne, Australia on 12 May 2014.

PubMed

Kessler, C; Oldenburg, J; Ettingshausen, C Escuriola; Tiede, A; Khair, K; Négrier, C; Klamroth, R

2015-01-01

Inhibitor development is the most serious and challenging complication in the treatment of severe haemophilia A. Up to 38% of such patients develop inhibitors with current recombinant factor VIII (rFVIII) products produced in hamster cell lines. Human-cl rhFVIII is a new generation fully sulfated B-domain-deleted FVIII coagulant glycoprotein, which is generated from a human cell line. Thus, there are no non-human epitopes which would be potentially immunogenic. This molecule has significantly higher VWF-binding affinity compared with existing full-length rFVIII produced in hamster cell lines. The development aim of Human-cl rhFVIII is to address the challenges of FVIII inhibitors and frequent infusions during prophylaxis. Human-cl rhFVIII's mean half-life is very comparable to some of the newer products which involve modification of the FVIII molecule to extend the circulating half-life. There are promising data concerning the use of a personalized prophylaxis regimen with Human-cl rhFVIII. Preliminary data indicate a median dosing interval of 3.5 days with 66.7% of the patients on a twice per week or fewer infusions schedule combined with a low bleeding rate and no increased FVIII consumption when compared to standard prophylaxis. No product-specific laboratory assay is required to monitor the coagulation activity for Human-cl rhFVIII. The results of registration clinical trials with Human-cl rhFVIII as well as the ongoing studies in previously untreated patients (NuProtect) and personalized prophylaxis study in previously treated patients (NuPreviq), will be discussed. The manufacturer has received marketing authorization for Human-cl rhFVIII in Europe and Canada under the name Nuwiq(®) and plans to launch it in the USA and globally in 2015. © 2014 John Wiley & Sons Ltd.

Coagulation disorders in dogs with hepatic disease.

PubMed

Prins, M; Schellens, C J M M; van Leeuwen, M W; Rothuizen, J; Teske, E

2010-08-01

Liver disease has been associated with abnormalities in haemostasis. In this study, coagulation times, platelet counts, platelet activity parameters, activities of individual coagulation factors, D-dimers, antithrombin (AT) and protein C activity were measured in 42 dogs with histologically confirmed liver disease. Outcome was correlated with histological diagnosis. One or more coagulation abnormalities were present in 57% of dogs with hepatic disease. Activated partial thromboplastin time was significantly prolonged in dogs with chronic hepatitis (CH), with or without cirrhosis. Mean platelet numbers, AT and factor IX activity were significantly lower in dogs with CH plus cirrhosis, compared to dogs with other hepatopathies. D-dimers were not significantly increased in any group. Only three dogs, all with different histological diagnoses, satisfied the criteria for disseminated intravascular coagulation (DIC). Haemostatic abnormalities were primarily seen in dogs with cirrhosis and this may be due to reduced synthesis rather than increased consumption of coagulation factors. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

An updated concept of coagulation with clinical implications.

PubMed

Romney, Gregory; Glick, Michael

2009-05-01

Over the past century, a series of models have been put forth to explain the coagulation mechanism. The coagulation cascade/waterfall model has gained the most widespread acceptance. This model, however, has problems when it is used in different clinical scenarios. A more recently proposed cell-based model better describes the coagulation process in vivo and provides oral health care professionals (OHCPs) with a better understanding of the clinical implications of providing dental care to patients with potentially increased bleeding tendencies. The authors conducted a literature search using the PubMed database. They searched for key words including "coagulation," "hemostasis," "bleeding," "coagulation factors," "models," "prothrombin time," "activated partial thromboplastin time," "international normalized ratio," "anticoagulation therapy" and "hemophilia" separately and in combination. The coagulation cascade/waterfall model is insufficient to explain coagulation in vivo, predict a patient's bleeding tendency, or correlate clinical outcomes with specific laboratory screening tests such as prothrombin time, activated partial thromboplastin time and international normalized ratio. However, the cell-based model of coagulation that reflects the in vivo process of coagulation provides insight into the clinical ramifications of treating dental patients with specific coagulation factor deficiencies. Understanding the in vivo coagulation process will help OHCPs better predict a patient's bleeding tendency. In addition, applying the theoretical concept of the cell-based model of coagulation to commonly used laboratory screening tests for coagulation and bleeding will result in safer and more appropriate dental care.

Polymorphisms of the factor VII gene associated with the low activities of vitamin K-dependent coagulation factors in one-month-old infants.

PubMed

Ito, Koichi; Goto, Kenji; Sugiura, Tokio; Muramatsu, Kanji; Ando, Toshihiro; Maniwa, Hiroko; Yokoyama, Takao; Sugiyama, Kohachiro; Togari, Hajime

2007-01-01

Despite administration of vitamin K (VK), some infants show lower activity of VK-dependent coagulation factors and they could develop intracranial hemorrhage. For preventing VK deficiency bleeding (VKDB) in infants, oral administration of VK and a screening test for VK deficiency are carried out in Japan. For the screening, the total activity of VK-dependent coagulation factors is measured using a commercial product, Normotest. This study was undertaken to clarify the importance of the following genetic and environmental factors on the coagulation status in one-month-old infants: two polymorphisms in the factor VII gene, -323P0/10 (a 10-bp insertion in the promoter region at position -323) and R353Q (the replacement of arginine [R] with glutamine [Q] at residue 353) and sex, age, gestational age, birth weight, and feeding regimen. Two hundred Japanese infants (34.6 +/- 4.0 days old) were screened for VK-dependent coagulation activity with Normotest and were genotyped for the two polymorphisms. Among the subjects screened, 18 infants (9%) carried the P10 allele and 26 (13%) carried the R353Q allele. Multiple regression analysis showed that the 10-bp inserted (P10) allele or the Q allele was associated with the lower coagulation activities. The coagulation activities for the R/Q genotype were significantly lower than those for the R/R genotype and those for the P0/P10 genotype were significantly lower than those for the P0/P0 genotype. Therefore, infants who carry the P10 allele or the Q allele show lower activity of VK-dependent coagulation factors. These infants may have a higher risk of VKDB manifestation.

Genetic Factors Influencing Coagulation Factor XIII B-Subunit Contribute to Risk of Ischemic Stroke.

PubMed

Hanscombe, Ken B; Traylor, Matthew; Hysi, Pirro G; Bevan, Stephen; Dichgans, Martin; Rothwell, Peter M; Worrall, Bradford B; Seshadri, Sudha; Sudlow, Cathie; Williams, Frances M K; Markus, Hugh S; Lewis, Cathryn M

2015-08-01

Abnormal coagulation has been implicated in the pathogenesis of ischemic stroke, but how this association is mediated and whether it differs between ischemic stroke subtypes is unknown. We determined the shared genetic risk between 14 coagulation factors and ischemic stroke and its subtypes. Using genome-wide association study results for 14 coagulation factors from the population-based TwinsUK sample (N≈2000 for each factor), meta-analysis results from the METASTROKE consortium ischemic stroke genome-wide association study (12 389 cases, 62 004 controls), and genotype data for 9520 individuals from the WTCCC2 ischemic stroke study (3548 cases, 5972 controls-the largest METASTROKE subsample), we explored shared genetic risk for coagulation and stroke. We performed three analyses: (1) a test for excess concordance (or discordance) in single nucleotide polymorphism effect direction across coagulation and stroke, (2) an estimation of the joint effect of multiple coagulation-associated single nucleotide polymorphisms in stroke, and (3) an evaluation of common genetic risk between coagulation and stroke. One coagulation factor, factor XIII subunit B (FXIIIB), showed consistent effects in the concordance analysis, the estimation of polygenic risk, and the validation with genotype data, with associations specific to the cardioembolic stroke subtype. Effect directions for FXIIIB-associated single nucleotide polymorphisms were significantly discordant with cardioembolic disease (smallest P=5.7×10(-04)); the joint effect of FXIIIB-associated single nucleotide polymorphisms was significantly predictive of ischemic stroke (smallest P=1.8×10(-04)) and the cardioembolic subtype (smallest P=1.7×10(-04)). We found substantial negative genetic covariation between FXIIIB and ischemic stroke (rG=-0.71, P=0.01) and the cardioembolic subtype (rG=-0.80, P=0.03). Genetic markers associated with low FXIIIB levels increase risk of ischemic stroke cardioembolic subtype. © 2015 The Authors.

Different Recovery Profiles of Coagulation Factors, Thrombin Generation, and Coagulation Function After Hemorrhagic Shock in Pigs

DTIC Science & Technology

2012-06-06

Different recovery profiles of coagulation factors, thrombin generation, and coagulation function after hemorrhagic shock in pigs Wenjun Z. Martini ...Defense. Address for reprints: Wenjun Z. Martini , PhD, The US Army Institute of Surgical Research, 3698 Chambers Pass, Ft. Sam Houston, San Antonio, TX...control number 1. REPORT DATE 01 SEP 2015 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Different recovery profiles of

Evaluation of the biological differences of canine and human factor VIII in gene delivery: Implications in human hemophilia treatment

USDA-ARS?s Scientific Manuscript database

The canine is the most important large animal model for testing novel hemophilia A(HA) treatment. It is often necessary to use canine factor VIII (cFIII) gene or protein for the evaluation of HA treatment in the canine model. However, the different biological properties between cFVIII and human FVII...

Inflammatory markers and exposure to airborne particles among workers in a Swedish pulp and paper mill.

PubMed

Westberg, Håkan; Elihn, Karine; Andersson, Eva; Persson, Bodil; Andersson, Lennart; Bryngelsson, Ing-Liss; Karlsson, Cathe; Sjögren, Bengt

2016-07-01

To study the relationship between exposure to airborne particles in a pulp and paper mill and markers of inflammation and coagulation in blood. Personal sampling of inhalable dust was performed for 72 subjects working in a Swedish pulp and paper mill. Stationary measurements were used to study concentrations of total dust, respirable dust, PM10 and PM2.5, the particle surface area and the particle number concentrations. Markers of inflammation, interleukins (IL-1b, IL-6, IL-8, and IL-10), C-reactive protein (CRP), serum amyloid A (SAA), and fibrinogen and markers of coagulation factor VIII, von Willebrand, plasminogen activator inhibitor, and D-dimer were measured in plasma or serum. Sampling was performed on the last day of the work free period of 5 days, before and after the shift the first day of work and after the shifts the second and third day. In a mixed model analysis, the relationship between particulate exposures and inflammatory markers was determined. Sex, age, smoking, and BMI were included as covariates. The average 8-h time-weighted average (TWA) air concentration levels of inhalable dust were 0.30 mg/m(3), range 0.005-3.3 mg/m(3). The proxies for average 8-h TWAs of respirable dust were 0.045 mg/m(3). Significant and consistent positive relations were found between several exposure metrics (PM 10, total and inhalable dust) and CRP, SAA and fibrinogen taken post-shift, suggesting a dose-effect relationship. This study supports a relationship between occupational particle exposure and established inflammatory markers, which may indicate an increased risk of cardiovascular disease.

Coagulation management in trauma-associated coagulopathy: allogenic blood products versus coagulation factor concentrates in trauma care.

PubMed

Klages, Matthias; Zacharowski, Kai; Weber, Christian Friedrich

2016-04-01

Coagulation management by transfusion of allogenic blood products and coagulation factors are competing concepts in current trauma care. Rapid and adequate therapy of trauma-associated coagulopathy is crucial to survival of severely injured patients. Standard coagulation tests such as prothrombin time and activated partial thromboplastin time are commonly used, but these tests are inappropriate for monitoring and guiding therapy in trauma patients. Coagulation factor-based treatment showed promising results, but randomized trials have not yet been performed. In addition, viscoelastic tests are needed to guide therapy, although there is in fact limited evidence for these in tests in trauma care. Regarding transfusion therapy with allogenic blood products, plasma transfusion has been associated with improved survival in trauma patients following massive transfusion. In contrast, patients not requiring massive transfusion seem to be at risk for suffering complications with increasing volumes of plasma transfused. The collective of trauma patients is heterogeneous. Despite the lack of evidence, there are strong arguments for individualized patient treatment with coagulation factors for some indications and to abstain from the use of fresh frozen plasma. In patients with severe trauma and major bleeding, plasma, platelets, and red blood cells should be considered to be administered at a ratio of 1 : 1 : 1.

Staining for factor VIII related antigen and Ulex europaeus agglutinin I (UEA-I) in 230 tumours. An assessment of their specificity for angiosarcoma and Kaposi's sarcoma.

PubMed

Leader, M; Collins, M; Patel, J; Henry, K

1986-11-01

In this study we examined the staining reactivity of commercially available antisera to factor VIII related antigen (F VIII RAg) and Ulex europaeus agglutinin I (UEA-I) on sections from 230 formalin fixed paraffin embedded tumours. These included 196 sarcomas, 20 carcinomas and 14 angiomas. All angiomas showed positive staining for F VIII RAg; all carcinomas showed negative staining; the vasoformative areas of all angiosarcomas stained positively but only four of six angiosarcomas showed positive staining of their solid areas; of seven Kaposi's sarcomas, all showed positive staining of vessels and six showed positive staining of the spindle cell component. In the remaining 181 non-vascular sarcomas there was a false positive result in four tumours (2.2%), three of which had a history of irradiation. Pre-radiotherapy biopsies of these three tumours stained negatively with anti-F VIII RAg. UEA-I was demonstrated in all the angiomas studied, in all angiosarcomas (including the solid components) and in well-formed vessels of all Kaposi's sarcomas, but only in the spindle cell component of 3/6. However, there was an unacceptably high rate of false positive staining amongst the carcinomas and non-vascular sarcomas. In conclusion, F VIII RAg is a specific but not a sensitive marker of angiosarcomas; UEA-I is a sensitive but not a specific marker of angiosarcomas.

Development and Implementation of a Coagulation Factor Testing Method Utilizing Autoverification in a High-volume Clinical Reference Laboratory Environment

PubMed Central

Riley, Paul W.; Gallea, Benoit; Valcour, Andre

2017-01-01

Background: Testing coagulation factor activities requires that multiple dilutions be assayed and analyzed to produce a single result. The slope of the line created by plotting measured factor concentration against sample dilution is evaluated to discern the presence of inhibitors giving rise to nonparallelism. Moreover, samples producing results on initial dilution falling outside the analytic measurement range of the assay must be tested at additional dilutions to produce reportable results. Methods: The complexity of this process has motivated a large clinical reference laboratory to develop advanced computer algorithms with automated reflex testing rules to complete coagulation factor analysis. A method was developed for autoverification of coagulation factor activity using expert rules developed with on an off the shelf commercially available data manager system integrated into an automated coagulation platform. Results: Here, we present an approach allowing for the autoverification and reporting of factor activity results with greatly diminished technologist effort. Conclusions: To the best of our knowledge, this is the first report of its kind providing a detailed procedure for implementation of autoverification expert rules as applied to coagulation factor activity testing. Advantages of this system include ease of training for new operators, minimization of technologist time spent, reduction of staff fatigue, minimization of unnecessary reflex tests, optimization of turnaround time, and assurance of the consistency of the testing and reporting process. PMID:28706751

Development and Implementation of a Coagulation Factor Testing Method Utilizing Autoverification in a High-volume Clinical Reference Laboratory Environment.

PubMed

Riley, Paul W; Gallea, Benoit; Valcour, Andre

2017-01-01

Testing coagulation factor activities requires that multiple dilutions be assayed and analyzed to produce a single result. The slope of the line created by plotting measured factor concentration against sample dilution is evaluated to discern the presence of inhibitors giving rise to nonparallelism. Moreover, samples producing results on initial dilution falling outside the analytic measurement range of the assay must be tested at additional dilutions to produce reportable results. The complexity of this process has motivated a large clinical reference laboratory to develop advanced computer algorithms with automated reflex testing rules to complete coagulation factor analysis. A method was developed for autoverification of coagulation factor activity using expert rules developed with on an off the shelf commercially available data manager system integrated into an automated coagulation platform. Here, we present an approach allowing for the autoverification and reporting of factor activity results with greatly diminished technologist effort. To the best of our knowledge, this is the first report of its kind providing a detailed procedure for implementation of autoverification expert rules as applied to coagulation factor activity testing. Advantages of this system include ease of training for new operators, minimization of technologist time spent, reduction of staff fatigue, minimization of unnecessary reflex tests, optimization of turnaround time, and assurance of the consistency of the testing and reporting process.

Evaluation of B&W UO2/ThO2 VIII experimental core: criticality and thermal disadvantage factor analysis

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

Carlo Parisi; Emanuele Negrenti

2017-02-01

In the framework of the OECD/NEA International Reactor Physics Experiment (IRPHE) Project, an evaluation of core VIII of the Babcock & Wilcox (B&W) Spectral Shift Control Reactor (SSCR) critical experiment program was performed. The SSCR concept, moderated and cooled by a variable mixture of heavy and light water, envisaged changing of the thermal neutron spectrum during the operation to encourage breeding and to sustain the core criticality. Core VIII contained 2188 fuel rods with 93% enriched UO2-ThO2 fuel in a moderator mixture of heavy and light water. The criticality experiment and measurements of the thermal disadvantage factor were evaluated.

Economic aspects of intraoperative coagulation management targeting higher fibrinogen concentrations during major craniosynostosis surgery.

PubMed

Haas, Thorsten; Spielmann, Nelly; Restin, Tanja; Schmidt, Alexander R; Schmugge, Markus; Cushing, Melissa M

2016-01-01

Results of a previously published study demonstrated a significant decrease in transfusion requirements and calculated blood loss for pediatric major craniosynostosis surgery, if a ROTEM(®) FIBTEM trigger of <13 mm (early substitution group) was applied as compared to a trigger of <8 mm (conventional group). The aim of this study was a posthoc analysis of the costs for this coagulation management. The total volume as well as the number of units or bags for all transfused blood products and coagulation factors were recorded for each case. The number of laboratory and point-of-care coagulation tests was also analyzed. Total blood product costs were calculated according to the local prices per unit. The total cost for all transfused/administered blood products/coagulation factors per patient was a median of 1023EUR (IQR 850EUR-1058EUR) in the early substitution group as compared to a median of 910EUR (IQR 719EUR-1351EUR) in the conventional group (P = 0.81). No difference in the number of coagulation tests performed was observed. In this study, the use of a higher fibrinogen trigger was not linked to a significant increase in total costs for transfused blood products and coagulation factors, and may offer an economically equivalent approach to coagulation management. © 2015 John Wiley & Sons Ltd.

Genetic engineering for haemophilia A.

PubMed

Gan, Shu Uin; Kon, Oi Lian; Calne, Roy Y

2006-10-01

At first sight, haemophilia A would appear to be an ideal candidate for treatment by gene therapy. There is a single gene defect; cells in different parts of the body, but especially the liver, produce Factor VIII, and only 5% of normal levels of Factor VIII are necessary to prevent the serious symptoms of bleeding. This review attempts to outline the status of gene therapy at present and efforts that have been made to overcome the difficulties and remaining problems that require solving. Undoubtedly, success will be achieved, but it is likely that considerably more work will be necessary before experimental models can be introduced into the clinic with any likelihood of success. The most successful results in animals that may have clinical application were from introducing the Factor VIII gene to newborn animals before antibodies are produced, presumably inducing a state of tolerance.

Functional genomics in zebrafish permits rapid characterization of novel platelet membrane proteins.

PubMed

O'Connor, Marie N; Salles, Isabelle I; Cvejic, Ana; Watkins, Nicholas A; Walker, Adam; Garner, Stephen F; Jones, Chris I; Macaulay, Iain C; Steward, Michael; Zwaginga, Jaap-Jan; Bray, Sarah L; Dudbridge, Frank; de Bono, Bernard; Goodall, Alison H; Deckmyn, Hans; Stemple, Derek L; Ouwehand, Willem H

2009-05-07

In this study, we demonstrate the suitability of the vertebrate Danio rerio (zebrafish) for functional screening of novel platelet genes in vivo by reverse genetics. Comparative transcript analysis of platelets and their precursor cell, the megakaryocyte, together with nucleated blood cell elements, endothelial cells, and erythroblasts, identified novel platelet membrane proteins with hitherto unknown roles in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)-based knockdown of 5 of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet glycoprotein (GP) IIb and the coagulation protein factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of 4 of the 5 novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBI and LRRC32 in promotion and DCBLD2 and ESAM in inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis.

Functional genomics in zebrafish permits rapid characterization of novel platelet membrane proteins

PubMed Central

O'Connor, Marie N.; Salles, Isabelle I.; Cvejic, Ana; Watkins, Nicholas A.; Walker, Adam; Garner, Stephen F.; Jones, Chris I.; Macaulay, Iain C.; Steward, Michael; Zwaginga, Jaap-Jan; Bray, Sarah L.; Dudbridge, Frank; de Bono, Bernard; Goodall, Alison H.; Stemple, Derek L.; Ouwehand, Willem H.

2009-01-01

In this study, we demonstrate the suitability of the vertebrate Danio rerio (zebrafish) for functional screening of novel platelet genes in vivo by reverse genetics. Comparative transcript analysis of platelets and their precursor cell, the megakaryocyte, together with nucleated blood cell elements, endothelial cells, and erythroblasts, identified novel platelet membrane proteins with hitherto unknown roles in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)–based knockdown of 5 of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet glycoprotein (GP) IIb and the coagulation protein factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of 4 of the 5 novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBI and LRRC32 in promotion and DCBLD2 and ESAM in inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis. PMID:19109564

Safety of intra-articular transplantation of lentivirally transduced mesenchymal stromal cells for haemophilic arthropathy in a non-human primate.

PubMed

Ohmori, Tsukasa; Mizukami, Hiroaki; Katakai, Yuko; Kawai, Sho; Nakamura, Hitoyasu; Inoue, Makoto; Shu, Tsugumine; Sugimoto, Hideharu; Sakata, Yoichi

2018-05-08

Joint bleeding and resultant arthropathy are major determinants of quality of life in haemophilia patients. We previously developed a mesenchymal stromal cell (MSC)-based treatment approach for haemophilic arthropathy in a mouse model of haemophilia A. Here, we evaluated the long-term safety of intra-articular injection of lentivirally transduced autologous MSCs in non-human primates. Autologous bone-marrow-derived MSCs transduced with a lentiviral vector expressing coagulation factor VIII (FVIII) were injected into the left knee joint of cynomolgus monkeys. We first conducted codon optimization to increase FVIII production in the cells. Lentiviral transduction of autologous MSCs resulted in a significant increase of FVIII in the culture supernatant before transplantation. We did not find any tumour generation around the knee structure at 11-16 months after injection by magnetic resonance imaging. The proviral sequence of the simian immunodeficiency virus lentiviral vector was not detected in the heart, lungs, spleen, liver, testis, or bone marrow by real-time quantitative PCR. We confirmed the long-term safety of intra-articular injection of transduced MSCs in a non-human primate. The procedure may be an attractive therapeutic approach for joint diseases in haemophilia patients.

Role of tissue factor and protease-activated receptors in a mouse model of endotoxemia.

PubMed

Pawlinski, Rafal; Pedersen, Brian; Schabbauer, Gernot; Tencati, Michael; Holscher, Todd; Boisvert, William; Andrade-Gordon, Patricia; Frank, Rolf Dario; Mackman, Nigel

2004-02-15

Sepsis is associated with a systemic activation of coagulation and an excessive inflammatory response. Anticoagulants have been shown to inhibit both coagulation and inflammation in sepsis. In this study, we used both genetic and pharmacologic approaches to analyze the role of tissue factor and protease-activated receptors in coagulation and inflammation in a mouse endotoxemia model. We used mice expressing low levels of the procoagulant molecule, tissue factor (TF), to analyze the effects of TF deficiency either in all tissues or selectively in hematopoietic cells. Low TF mice had reduced coagulation, inflammation, and mortality compared with control mice. Similarly, a deficiency of TF expression by hematopoietic cells reduced lipopolysaccharide (LPS)-induced coagulation, inflammation, and mortality. Inhibition of the down-stream coagulation protease, thrombin, reduced fibrin deposition and prolonged survival without affecting inflammation. Deficiency of either protease activated receptor-1 (PAR-1) or protease activated receptor-2 (PAR-2) alone did not affect inflammation or survival. However, a combination of thrombin inhibition and PAR-2 deficiency reduced inflammation and mortality. These data demonstrate that hematopoietic cells are the major pathologic site of TF expression during endotoxemia and suggest that multiple protease-activated receptors mediate crosstalk between coagulation and inflammation.

Effect of circulating tissue factor on hypercoagulability in type 2 diabetes mellitus studied by rheometry and dielectric blood coagulometry.

PubMed

Uchimura, Isao; Kaibara, Makoto; Nagasawa, Masayuki; Hayashi, Yoshihito

2016-01-01

Hypercoagulability in type 2 diabetes mellitus (T2DM) patients increases their risk of cardiovascular diseases. The aim of this work was to investigate the hypercoagulation mechanism in T2DM patients in terms of circulating tissue factor (TF). Whole blood coagulation tests by damped oscillation rheometry and dielectric blood coagulometry (DBCM) were performed. The average coagulation time was significantly shorter for T2DM patients than for healthy controls. In vitro addition of either anti-TF or anti-activated factor VII (FVIIa) antibody to hypercoagulable blood samples prolonged coagulation times for one group of patients, while coagulation times remained short for another group. The levels of circulating TF were estimated in the former group by measuring the coagulation times for blood samples from healthy subjects with addition of various concentrations of TF and comparing them with the coagulation times for the group. The results indicated that the levels of circulating TF were on the order of subpicomolar at most. Circulating TF is at least partially responsible for a hypercoagulable group of T2DM patients, while an abnormality in the intrinsic coagulation pathway probably occurs in the other group.

Multiple roles of the coagulation protease cascade during virus infection.

PubMed

Antoniak, Silvio; Mackman, Nigel

2014-04-24

The coagulation cascade is activated during viral infections. This response may be part of the host defense system to limit spread of the pathogen. However, excessive activation of the coagulation cascade can be deleterious. In fact, inhibition of the tissue factor/factor VIIa complex reduced mortality in a monkey model of Ebola hemorrhagic fever. Other studies showed that incorporation of tissue factor into the envelope of herpes simplex virus increases infection of endothelial cells and mice. Furthermore, binding of factor X to adenovirus serotype 5 enhances infection of hepatocytes but also increases the activation of the innate immune response to the virus. Coagulation proteases activate protease-activated receptors (PARs). Interestingly, we and others found that PAR1 and PAR2 modulate the immune response to viral infection. For instance, PAR1 positively regulates TLR3-dependent expression of the antiviral protein interferon β, whereas PAR2 negatively regulates expression during coxsackievirus group B infection. These studies indicate that the coagulation cascade plays multiple roles during viral infections.

Acute Coagulopathy of Trauma in the Rat

DTIC Science & Technology

2013-01-01

coagulation and include prothrombin complex con- centrate, recombinant activated FVII , tranexamic acid, and fibrinogen (13, 14). The degree of coagulopathy...extrinsic pathway using tissue factor to initiate coagulation as would be expected following tissue injury. Cytochalasin D (inhibit platelet function in...chalasin D. ! Angle was elevated, and clotting time was shortened, suggesting that coagulation factors were activated and adequate to support thrombin

Clotting factor VIII (FVIII) and thrombin generation in camel plasma: A comparative study with humans

PubMed Central

Abdel Gader, Abdel Galil M.; Al Momen, Abdul Karim M.; Alhaider, Abdulqader; Brooks, Marjory B.; Catalfamo, James L.; Al Haidary, Ahmed A.; Hussain, Mansour F.

2013-01-01

The objective of this study was to characterize the highly elevated levels of clotting factor VIII (FVIII) in camel plasma. Whole blood was collected from healthy camels and factor VIII clotting activity (FVIII:C) assays were conducted using both the clotting and the chromogenic techniques. The anticoagulant citrate phosphate dextrose adenine (CPDA) produced the highest harvest of FVIII:C, the level of plasma factor VIII, compared to heparin:saline and heparin:CPDA anticoagulants. Camel FVIII can be concentrated 2 to 3 times in cryoprecipitate. There was a significant loss of camel FVIII when comparing levels of FVIII in camel plasma after 1 h of incubation at 37°C (533%), 40°C (364%), and 50°C (223%). Thrombin generation of camel plasma is comparable to that of human plasma. It was concluded that camel plasma contains very elevated levels of FVIII:C, approaching 8 times the levels in human plasma, and that these elevated levels could not be attributed to excessive thrombin generation. Unlike human FVIII:C, camel FVIII:C is remarkably heat stable. Taken together, these unique features of camel FVIII could be part of the physiological adaptation of hemostasis of the Arabian camel in order to survive in the hot desert environment. PMID:24082408

21 CFR 864.7750 - Prothrombin time test.

Code of Federal Regulations, 2010 CFR

2010-04-01

... the detection of possible clotting factor deficiencies in the extrinsic coagulation pathway, which involves the reaction between coagulation factors III and VII, and to monitor patients receiving coumarin...

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

Parvinen, M.; Soeder, O.M.; Mali, P.

Levels of rat testicular interleukin-1-like factor (tIL-1) have been shown to correlate with DNA synthetic activity during the cycle of the rat seminiferous epithelium, suggesting its role as a spermatogonial or meiotic growth factor. To explore this further, a new in vitro model system was developed. Rat seminiferous tubule segments from stages I, V, VIIa, and VIII-IX of the cycle were isolated by transillumination-assisted microdissection, cultured in chemically defined serum-free medium supplemented with human recombinant IL-1 {alpha}, and labeled with (3H)thymidine. During incubation, spontaneous progression of spermatogenesis was noted. Inactive stage VIIa tubule segments differentiated to stage VIII and initiatedmore » DNA synthesis, and concomitantly started to secrete IL-1-like factor. DNA synthesis of stages VIII-IX ceased through differentiation of spermatocytes to leptotene-zygotene (stages XII-XIII of the cycle). IL-1 {alpha} stimulated DNA synthesis significantly in spermatogonia of stage I. Meiotic DNA synthesis at stage VIIa was stimulated (48 h/34 C) and maintained at stages VIII-IX (48 h/34 C). IL-1 {alpha} seems to act as a regulator of spermatogenic DNA synthesis in both mitotic and meiotic phases. It has mainly stimulating and maintaining effects, but it may also be inhibitory under certain conditions.« less

Hereditary and acquired thrombophilia in patients with upper extremity deep-vein thrombosis. Results from the MAISTHRO registry.

PubMed

Linnemann, Birgit; Meister, Florian; Schwonberg, Jan; Schindewolf, Marc; Zgouras, Dimitrios; Lindhoff-Last, Edelgard

2008-09-01

The prevalence of coagulation disorders in patients with upper extremity deep-vein thrombosis (UE-DVT) is unknown due to only a few observational studies of limited size reporting varying results. Therefore, we aimed to evaluate the prevalence of thrombophilia in patients with UE-DVT compared to patients with lower extremity deep vein thrombosis (LE-DVT). One hundred fifty consecutive patients (15 to 91 years of age) with UE-DVT were recruited from the MAISTHRO (MAin-ISar-THROmbosis) registry. Three hundred LE-DVT patients matched for gender and age served as controls. Thrombophilia screening included tests for the factor V Leiden mutation, the prothrombin G20210A mutation, antiphospholipid antibodies and factor VIII (FVIII), protein C, protein S and antithrombin activities. At least one thrombophilia was present in 34.2% of UE-DVT and 39.2% in UE-DVT that was unrelated to venous catheters relative to 55.3% in LE-DVT patients (p<0.001). In particular, a persistently elevated FVIII is less likely to be found in UE-DVT patients than in those with LE-DVT and is the only thrombophilia that is differentially expressed after controlling for established VTE risk factors [OR 0.46, (95% CI 0.25-0.83)]. Although less prevalent than in LE-DVT patients, thrombophilia is a common finding in patients with UE-DVT, especially in those with thrombosis that is unrelated to venous catheters.

Treatment of haemophilia and related disorders in Britain and Northern Ireland during 1976-80: report on behalf of the directors of haemophilia centres in the United Kingdom.

PubMed Central

Rizza, C R; Spooner, R J

1983-01-01

A five year survey of the treatment of patients in the United Kingdom suffering from haemophilia and related disorders was carried out on behalf of the directors of haemophilia centres. The survey showed an increase in the number of patients receiving treatment from the centres, a substantial increase in the total amount of therapeutic materials used, and an increase in the average amount of factor VIII or factor IX used yearly per patient. Home treatment became established for severely affected patients and accounted for roughly half of the total amount of material used. Study of the acquisition of factor VIII or factor IX antibodies (inhibitors) in patients with haemophilia A or haemophilia B showed no increase in antibodies during the survey period, despite the increased use of factor VIII and factor IX concentrates. The occurrence of acute hepatitis in treated patients was also studied and no increased incidence was observed. A near normal median expectation of life in patients with severe haemophilia A was found. PMID:6403138

Bioinformatic Characterization of Genes and Proteins Involved in Blood Clotting in Lampreys.

PubMed

Doolittle, Russell F

2015-10-01

Lampreys and hagfish are the earliest diverging of extant vertebrates and are obvious targets for investigating the origins of complex biochemical systems found in mammals. Currently, the simplest approach for such inquiries is to search for the presence of relevant genes in whole genome sequence (WGS) assemblies. Unhappily, in the past a high-quality complete genome sequence has not been available for either lampreys or hagfish, precluding the possibility of proving gene absence. Recently, improved but still incomplete genome assemblies for two species of lamprey have been posted, and, taken together with an extensive collection of short sequences in the NCBI trace archive, they have made it possible to make reliable counts for specific gene families. Particularly, a multi-source tactic has been used to study the lamprey blood clotting system with regard to the presence and absence of genes known to occur in higher vertebrates. As was suggested in earlier studies, lampreys lack genes for coagulation factors VIII and IX, both of which are critical for the "intrinsic" clotting system and responsible for hemophilia in humans. On the other hand, they have three each of genes for factors VII and X, participants in the "extrinsic" clotting system. The strategy of using raw trace sequence "reads" together with partial WGS assemblies for lampreys can be used in studies on the early evolution of other biochemical systems in vertebrates.

Reassessment of ABO blood group, sex, and age on laboratory parameters used to diagnose von Willebrand disorder: potential influence on the diagnosis vs the potential association with risk of thrombosis.

PubMed

Favaloro, Emmanuel J; Soltani, Soma; McDonald, Jane; Grezchnik, Ella; Easton, Leanne; Favaloro, James W C

2005-12-01

We reassessed the influence of ABO blood group, sex, and age on plasma levels of von Willebrand factor (vWF) antigen, vWF:ristocetin cofactor, vWF:collagen binding assay, and factor VIII coagulant (FVIII:C). Data show that levels of vWF and FVIII:C increase with increasing age (P < .001 for all parameters) and that the ABO blood group influences plasma levels such that O group levels are significantly less than non-O group levels. There was no significant association with sex and Rh status. The selection of normal ranges based on ABO blood groups may influence the clinical diagnosis of von Willebrand disease (vWD) but might not be clinically relevant or help identify people at increased risk of bleeding. Differences in ABO-related ranges were more extensive at the high end of the ranges. This is of particular interest because high levels of vWF and FVIII are associated with thrombosis risk, and an ABO relationship also has been described. O group individuals may or may not be at greater risk for bleeding (they have lower levels of vWF and FVIII:C) and are more likely to be diagnosed with vWD. It also is possible that O group status may be protective for thrombosis.

Omental implantation of BOECs in hemophilia dogs results in circulating FVIII antigen and a complex immune response.

PubMed

Ozelo, Margareth C; Vidal, Barbara; Brown, Christine; Notley, Colleen; Hegadorn, Carol; Webster, Sandra; Harpell, Lori; Ahlin, James; Winterborn, Andrew; Handforth, Janine; Arruda, Valder R; Hough, Christine; Lillicrap, David

2014-06-26

Ex vivo gene therapy strategies avoid systemic delivery of viruses thereby mitigating the risk of vector-associated immunogenicity. Previously, we delivered autologous factor VIII (FVIII)-expressing blood outgrowth endothelial cells (BOECs) to hemophilia A mice and showed that these cells remained sequestered within the implanted matrix and provided therapeutic levels of FVIII. Prior to translating this strategy into the canine (c) model of hemophilia A, we increased cFVIII transgene expression by at least 100-fold with the use of the elongation factor 1 alpha (EF1α) promoter and a strong endothelial enhancer element. BOECs isolated from hemophilia A dogs transduced with this lentiviral vector express levels of cFVIII ranging between 1.0 and 1.5 U/mL per 10(6) cells over 24 hours. Autologous BOECs have been implanted into the omentum of 2 normal and 3 hemophilia A dogs. These implanted cells formed new vessels in the omentum. All 3 hemophilia A dogs treated with FVIII-expressing autologous BOECs developed anti-FVIII immunoglobulin G2 antibodies, but in only 2 of the dogs were these antibodies inhibitory. FVIII antigen levels >40% in the absence of FVIII coagulant function were detected in the circulation for up to a year after a single gene therapy treatment, indicating prolonged cellular viability and synthesis of FVIII. © 2014 by The American Society of Hematology.

The rational design of a 'type 88' genetically stable peptide display vector in the filamentous bacteriophage fd.

PubMed

Enshell-Seijffers, D; Smelyanski, L; Gershoni, J M

2001-05-15

Filamentous bacteriophages are particularly efficient for the expression and display of combinatorial random peptides. Two phage proteins are often employed for peptide display: the infectivity protein, PIII, and the major coat protein, PVIII. The use of PVIII typically requires the expression of two pVIII genes: the wild-type and the recombinant pVIII gene, to generate mosaic phages. 'Type 88' vectors contain two pVIII genes in one phage genome. In this study a novel 'type 88' expression vector has been rationally designed and constructed. Two factors were taken into account: the insertion site and the genetic stability of the second pVIII gene. It was found that selective deletion of recombinant genes was encountered when inserts were cloned into either of the two non-coding regions of the phage genome. The deletions were independent of recA yet required a functional F-episome. Transcription was also found to be a positive factor for deletion. Taking the above into account led to the generation of a novel vector, designated fth1, which can be used to express recombinant peptides as pVIII chimeric proteins in mosaic bacteriophages. The fth1 vector is not only genetically stable but also of high copy number and produces high titers of recombinant phages.

Acquired Hemophilia A in an advanced age patient of hispanic origin: a case report.

PubMed

Rivera Cora, Nalyssa I; Irizarry Delgado, Freddie; Merle Ramírez, Santa M; Vera Quiñones, Jorge

2017-09-04

Acquired Hemophilia A (AHA) is a rare hematological disorder that exhibits an incidence of approximately 1.5 cases per million patients a year. It is characterized by the development of autoantibodies against circulating Factor VIII coagulation proteins which, in turn, which in turn lead to potentially life-threatening hemorrhagic episodes. The incidence of AHA increases with age; with 80% of the affected patient population encompassing men and women that are 65 years or older. Some of the challenges that are highlighted in managing this disorder relate to the delayed diagnosis of this condition due to the rarity of the latter, the difficulty in establishing reliable hemostasis, and the secondary complications that are found when using immunosuppressive and hemostatic treatments in tandem with the elderly population afflicted with this disease. A 90-year-old female of Hispanic origin presented with a 2-week history of generalized weakness, dizziness, shortness of breath and extensive purpuric formations that involved the left arm towards the lateral aspect of the thorax with the inclusion of a small right lateral neck hematoma formation. Upon initial laboratory screening, a hemoglobin level of 7.9, a hematocrit level of 21.9 and a PTT value of 70.9 were discovered. Despite conventional hemostatic treatment approaches, the patient did not show marked improvement of the laboratory values. Ongoing specialized laboratory reports, combined with the clinical presentation of the patient, led to the diagnosis of Acquired Hemophilia A. Treatment with recombinant porcine Factor VIII was initiated, which led to rapid improvement of clinical symptoms and laboratory values. The patient was discharged with current treatment plan and emergent follow/up with a hematologist was scheduled. Acquired Hemophilia A is an elusive bleeding disorder that has been seldom encountered in the demographics of Puerto Rico. The prompt detection of this diagnosis based on the clinical presentation alone is paramount to prevent the occurrence of grave hemorrhagic episodes. General knowledge and awareness of the treatment options available is key to ameliorate the prognosis of this ailment.

Combined variants in factor VIII and prostaglandin synthase-1 amplify hemorrhage severity across three generations of descendants.

PubMed

Nance, D; Campbell, R A; Rowley, J W; Downie, J M; Jorde, L B; Kahr, W H; Mereby, S A; Tolley, N D; Zimmerman, G A; Weyrich, A S; Rondina, M T

2016-11-01

Essentials Co-existent damaging variants are likely to cause more severe bleeding and may go undiagnosed. We determined pathogenic variants in a three-generational pedigree with excessive bleeding. Bleeding occurred with concurrent variants in prostaglandin synthase-1 (PTGS-1) and factor VIII. The PTGS-1 variant was associated with functional defects in the arachidonic acid pathway. Background Inherited human variants that concurrently cause disorders of primary hemostasis and coagulation are uncommon. Nevertheless, rare cases of co-existent damaging variants are likely to cause more severe bleeding and may go undiagnosed. Objective We prospectively sought to determine pathogenic variants in a three-generational pedigree with excessive bleeding. Patients/methods Platelet number, size and light transmission aggregometry to multiple agonists were evaluated in pedigree members. Transmission electron microscopy determined platelet morphology and granule content. Thromboxane release studies and light transmission aggregometry in the presence or absence of prostaglandin G 2 assessed specific functional defects in the arachidonic acid pathway. Whole exome sequencing (WES) and targeted nucleotide sequence analysis identified potentially deleterious variants. Results Pedigree members with excessive bleeding had impaired platelet aggregation with arachidonic acid, epinephrine and low-dose ADP, as well as reduced platelet thromboxane B 2 release. Impaired platelet aggregation in response to 2MesADP was rescued with prostaglandin G 2 , a prostaglandin intermediate downstream of prostaglandin synthase-1 (PTGS-1) that aids in the production of thromboxane. WES identified a non-synonymous variant in the signal peptide of PTGS-1 (rs3842787; c.50C>T; p.Pro17Leu) that completely co-segregated with disease phenotype. A variant in the F8 gene causing hemophilia A (rs28935203; c.5096A>T; p.Y1699F) was also identified. Individuals with both variants had more severe bleeding manifestations than characteristic of mild hemophilia A alone. Conclusion We provide the first report of co-existing variants in both F8 and PTGS-1 genes in a three-generation pedigree. The PTGS-1 variant was associated with specific functional defects in the arachidonic acid pathway and more severe hemorrhage. © 2016 International Society on Thrombosis and Haemostasis.

Analysis of aggregation of platelets in thrombosis

NASA Astrophysics Data System (ADS)

Ahuja, Suresh

Platelets are key players in thrombus formation by first rolling over collagen bound von Willebrand factor followed by formation of a stable interaction with collagen. The first adhered platelets bind additional platelets until the whole injury is sealed off by a platelet aggregate. The coagulation system stabilizes the formed platelet plug by creating a tight fibrin network, and then wound contraction takes place because of morphological changes in platelets. Coagulation takes place by platelet activation and aggregation mainly through fibrinogen polymerization into fibrin fibers. The process includes multiple factors, such as thrombin, plasmin, and local shear-rate which regulate and control the process. Coagulation can be divided into two pathways: the intrinsic pathway and the extrinsic pathway. The intrinsic pathway is initiated by the exposure of a negatively charged. It is able to activate factor XII, using a complex reaction that includes prekallikrein and high-molecular-weight kininogen as cofactors.. Thrombin is the final enzyme that is needed to convert fibrinogen into fibrin. The extrinsic pathway starts with the exposure of tissue factor to the circulating blood, which is the major initiator of coagulation. There are several feedback loops that reinforce the coagulation cascade, resulting in large amounts of thrombin. It is dependent on the presence of pro-coagulant surfaces of cells expressing negatively charged phospholipids--which include phosphatidylserine (PS)--on their outer membrane. PS-bearing surfaces are able to increase the efficiency of the reactions by concentrating and co-localizing coagulation factors.. Aggregation of platelets are analyzed and compared to adhesion of platelet to erythrocyte and to endothelial cells. This abstract is replacing MAR16-2015-020003.

Safety, efficacy and pharmacokinetics of rVIII-SingleChain in children with severe hemophilia A: results of a multicenter clinical trial.

PubMed

Stasyshyn, O; Djambas Khayat, C; Iosava, G; Ong, J; Abdul Karim, F; Fischer, K; Veldman, A; Blackman, N; St Ledger, K; Pabinger, I

2017-04-01

Essentials rVIII-SingleChain is a novel recombinant factor VIII with covalently bonded heavy and light chains. Efficacy, safety and pharmacokinetics were studied in pediatric patients with severe hemophilia A. Across all prophylaxis regimens, the median annualized spontaneous bleeding rate was 0.00. rVIII-SingleChain showed excellent hemostatic efficacy and a favorable safety profile. Background rVIII-SingleChain is a novel B-domain truncated recombinant factor VIII (rFVIII) comprised of covalently bonded FVIII heavy and light chains, demonstrating a high binding affinity to von Willebrand factor. Objectives This phase III study investigated the safety, efficacy and pharmacokinetics of rVIII-SingleChain in previously treated pediatric patients < 12 years of age with severe hemophilia A. Patients/Methods Patients could be assigned to prophylaxis or on-demand therapy by the investigator. For patients assigned to prophylaxis, the treatment regimen and dose were based on the bleeding phenotype. For patients receiving on-demand therapy, dosing was guided by World Federation of Hemophilia recommendations. The primary endpoint was treatment success, defined as a rating of 'excellent' or 'good' on the investigator's clinical assessment of hemostatic efficacy for all treated bleeding events. Results The study enrolled 84 patients (0 to < 6 years, n = 35; ≥ 6 to < 12 years, n = 49); 81 were assigned to prophylaxis and three to an on-demand regimen. Patients accumulated a total of 5239 exposure days (EDs), with 65 participants reaching > 50 EDs. In the 347 bleeds treated and evaluated by the investigator, hemostatic efficacy was rated as excellent or good in 96.3%. The median annualized spontaneous bleeding rate was 0.00 (Q1, Q3: 0.00, 2.20), and the median annualized bleeding rate was 3.69 (Q1, Q3: 0.00, 7.20) across all prophylaxis regimens. No participant developed an inhibitor. Conclusions rVIII-SingleChain is a novel rFVIII molecule showing excellent hemostatic efficacy and a favorable safety profile in a clinical study in children < 12 years of age with severe hemophilia A. © 2017 The Authors. Journal of Thrombosis and Haemostasis published by Wiley Periodicals, Inc. on behalf of International Society on Thrombosis and Haemostasis.

Monitoring and treatment of coagulation abnormalities in burn patients. an international survey on current practices

PubMed Central

Lavrentieva, A.; Depetris, N.; Kaimakamis, E.; Berardino, M.; Stella, M.

2016-01-01

Summary The magnitude of coagulation abnormalities, and the definition and treatment of coagulopathy in burn patients are inadequately understood and continue to be discussed in the literature. We aimed to analyse physicians’ views on monitoring and treating coagulation abnormalities in burn patients. A total of 350 questionnaires were distributed electronically to burn ICU physicians. Participation was voluntary and anonymous. Responses were analysed electronically and comparisons were made according to the region of the ICU or the specialty of the physician. Of the 350 questionnaires distributed, 55 (15.7%) were returned. The majority of burn specialists consider sepsis-induced coagulopathy to be the most frequent coagulopathy in burn patients, and 74.5% declare that they do not use any specific definition/scoring system in their department to detect coagulopathy. The majority of specialists (70.8%) use standard coagulation tests. The most frequent indications for plasma transfusion are massive bleeding (32.8%) and Disseminated Intravascular Coagulation syndrome treatment (20%). The main specific factors reported in our study are cryoprecipitate (23.2%) and fibrinogen concentrate (18.9%). 21.1% of respondents state that they do not use any specific coagulation factor substitution in burn patients. Specific coagulation factor substitution is not a routine practice. The low response rate precludes the generalization of our results. PMID:28149244

Effect of circulating tissue factor on hypercoagulability in type 2 diabetes mellitus studied by rheometry and dielectric blood coagulometry

PubMed Central

Uchimura, Isao; Kaibara, Makoto; Nagasawa, Masayuki; Hayashi, Yoshihito

2016-01-01

Background: Hypercoagulability in type 2 diabetes mellitus (T2DM) patients increases their risk of cardiovascular diseases. Objective: The aim of this work was to investigate the hypercoagulation mechanism in T2DM patients in terms of circulating tissue factor (TF). Methods: Whole blood coagulation tests by damped oscillation rheometry and dielectric blood coagulometry (DBCM) were performed. Results: The average coagulation time was significantly shorter for T2DM patients than for healthy controls. In vitro addition of either anti-TF or anti-activated factor VII (FVIIa) antibody to hypercoagulable blood samples prolonged coagulation times for one group of patients, while coagulation times remained short for another group. The levels of circulating TF were estimated in the former group by measuring the coagulation times for blood samples from healthy subjects with addition of various concentrations of TF and comparing them with the coagulation times for the group. The results indicated that the levels of circulating TF were on the order of subpicomolar at most. Conclusions: Circulating TF is at least partially responsible for a hypercoagulable group of T2DM patients, while an abnormality in the intrinsic coagulation pathway probably occurs in the other group. PMID:27858671

The polyphosphate–factor XII pathway drives coagulation in prostate cancer-associated thrombosis

PubMed Central

Nickel, Katrin F.; Ronquist, Göran; Langer, Florian; Labberton, Linda; Fuchs, Tobias A.; Bokemeyer, Carsten; Sauter, Guido; Graefen, Markus; Mackman, Nigel; Stavrou, Evi X.; Ronquist, Gunnar

2015-01-01

Cancer is a leading cause of thrombosis. We identify a new procoagulant mechanism that contributes to thromboembolism in prostate cancer and allows for safe anticoagulation therapy development. Prostate cancer-mediated procoagulant activity was reduced in plasma in the absence of factor XII or its substrate of the intrinsic coagulation pathway factor XI. Prostate cancer cells and secreted prostasomes expose long chain polyphosphate on their surface that colocalized with active factor XII and initiated coagulation in a factor XII-dependent manner. Polyphosphate content correlated with the procoagulant activity of prostasomes. Inherited deficiency in factor XI or XII or high-molecular-weight kininogen, but not plasma kallikrein, protected mice from prostasome-induced lethal pulmonary embolism. Targeting polyphosphate or factor XII conferred resistance to prostate cancer-driven thrombosis in mice, without increasing bleeding. Inhibition of factor XII with recombinant 3F7 antibody reduced the increased prostasome-mediated procoagulant activity in patient plasma. The data illustrate a critical role for polyphosphate/factor XII-triggered coagulation in prostate cancer-associated thrombosis with implications for anticoagulation without therapy-associated bleeding in malignancies. PMID:26153520

In Vitro Assessment of Nanoparticle Effects on Blood Coagulation.

PubMed

Potter, Timothy M; Rodriguez, Jamie C; Neun, Barry W; Ilinskaya, Anna N; Cedrone, Edward; Dobrovolskaia, Marina A

2018-01-01

Blood clotting is a complex process which involves both cellular and biochemical components. The key cellular players in the blood clotting process are thrombocytes or platelets. Other cells, including leukocytes and endothelial cells, contribute to clotting by expressing the so-called pro-coagulant activity (PCA) complex on their surface. The biochemical component of blood clotting is represented by the plasma coagulation cascade, which includes plasma proteins also known as coagulation factors. The coordinated interaction between platelets, leukocytes, endothelial cells, and plasma coagulation factors is necessary for maintaining hemostasis and for preventing excessive bleeding. Undesirable activation of all or some of these components may lead to pathological blood coagulation and life-threatening conditions such as consumptive coagulopathy or disseminated intravascular coagulation (DIC). In contrast, unintended inhibition of the coagulation pathways may lead to hemorrhage. Thrombogenicity is the property of a test material to induce blood coagulation by affecting one or more elements of the clotting process. Anticoagulant activity refers to the property of a test material to inhibit coagulation. The tendency to cause platelet aggregation, perturb plasma coagulation, and induce leukocyte PCA can serve as an in vitro measure of a nanomaterial's likelihood to be pro- or anticoagulant in vivo. This chapter describes three procedures for in vitro analyses of platelet aggregation, plasma coagulation time, and activation of leukocyte PCA. Platelet aggregation and plasma coagulation procedures have been described earlier. The revision here includes updated details about nanoparticle sample preparation, selection of nanoparticle concentration for the in vitro study, and updated details about assay controls. The chapter is expanded to describe a method for the leukocyte PCA analysis and case studies demonstrating the performance of these in vitro assays.

Reduced plasma levels of coagulation factors in relation to prostate cancer.

PubMed

Beecken, Wolf-Dietrich; Bentas, Wassilios; Engels, Knut; Glienke, Wolfgang; Urbschat, Anja; Jonas, Dietger; Binder, Jochen; Scharrer, Inge

2002-10-01

Prostate cancer has historically been associated with coagulation abnormalities. This study was undertaken to investigate the prevalence of abnormalities of coagulation factors in patients with prostate cancer before and after radical prostatectomy (RP). Because coagulation factors have been shown to be involved in tumor angiogenesis, the vascular density of the prostate tumors was assessed. Plasma of 40 consecutive patients with histologically proven prostate cancer was investigated pre-RP and post-RP. The antigen level for antithrombin, plasminogen activator inhibitor-1, and heparin cofactor-II, and the plasma activity of antithrombin and plasminogen were determined by using immunologic and chromogenic assays. The values of these assays were compared with a group of 28 male, age-matched patients without any evidence of cancer and 18 patients with orthopedic interventions preoperatively and postoperatively. The vascular density of the prostate tumors was assessed by staining paraffin sections with an antibody to CD34. The median plasma antigen levels and/or activities of the investigated factors were below normal in the prostate cancer patients before RP. Furthermore, coagulation factors were significantly lower than in the age-matched control group and patients before and after orthopedic surgery. In prostate cancer patients, the median values of all investigated factors went up to normal levels within 2 weeks after RP, whereas postsurgical levels in orthopedic patients remained stable. No correlations to tumor parameters have been observed. We assume that the reduction of these coagulation factors is a principle concept in prostate cancer that needs further investigation. Copyright 2002 Wiley-Liss, Inc.

Biomimetic transport and rational drug delivery.

PubMed

Ranney, D F

2000-01-15

Medicine and pharmaceutics are encountering critical needs and opportunities for transvascular drug delivery that improves site targeting and tissue permeation by mimicking natural tissue addressing and transport mechanisms. This is driven by the accelerated development of genomic agents requiring targeted controlled release. Although rationally designed for in vitro activity, such agents are not highly effective in vivo, due to opsonization and degradation by plasma constituents, and failure to transport across the local vascular endothelium and tissue matrix. A growing knowledge of the addresses of the body can be applied to engineer "Bio-Logically" staged delivery systems with sequential bioaddressins complementary to the discontinuous compartments encountered--termed discontinuum pharmaceutics. Effective tissue targeting is accomplished by leukocytes, bacteria, and viruses. We are increasingly able to mimic their bioaddressins by genomic means. Approaches described in this commentary include: (a) endothelial-directed adhesion mediated by oligosaccharides and carbohydrates (e.g. dermatan sulfate as a mimic of sulfated CD44) and peptidomimetics interacting with adhesins, selectins, integrins, hyaluronans, and locally induced growth factors (e.g. vascular endothelial growth factor, VEGF) and coagulation factors (e.g. factor VIII antigen); (b) improved tissue permeation conferred by hydrophilically "cloaked" carrier systems; (c) "uncloaking" by matrix dilution or selective triggering near the target cells; and (d) target binding-internalization by terminally exposed hydrophobic moieties, cationic polymers, and receptor-binding lectins, peptides, or carbohydrates. This commentary also describes intermediate technology solutions (e.g. "hybrid drugs"), and highlights the high-resolution, dynamic magnetic resonance imaging and radiopharmaceutical imaging technologies plus the groups and organizations capable of accelerating these important initiatives.

Congenital combined deficiency of coagulation factors: a study of seven patients.

PubMed

Naderi, Majid; Tabibian, Shadi; Hosseini, Maryam Sadat; Alizadeh, Shaban; Hosseini, Soudabeh; Shamsizadeh, Morteza; Dorgalaleh, Akbar

2015-01-01

Combined deficiency of coagulation factors is considered as an extremely rare bleeding disorder (RBD) inherited in an autosomal recessive pattern. This disorder is more likely to occur in regions with a high rate of consanguineous marriages or in restricted communities. Sistan and Baluchistan, a province in southeast of Iran with a high rate of consanguinity, is a clear model of such regions with a very high prevalence of recessively inherited disorders. The aim of this study was to report the frequency of combined factor deficiency in this province. This descriptive study was conducted on 358 patients with RBD. Demographic information and medical history of each patient were recorded, and the patients were examined by a physician. Routine screening tests were carried out for all patients, and further coagulation tests including coagulation factor activity and antigen assays were subsequently performed for all suspected patients. Among 358 patients, four were found to be affected with combined factor (F)V and FVIII deficiency (F5F8D). In addition, one patient with combined deficiency of FVII-FXIII, one with combined FVII-FX and one with combined FVIII-FIX deficiency were identified. In Sistan and Baluchistan Province, coinheritance of recessively inherited disorders like combined coagulation factor deficiencies was surprisingly higher than expected.

[Factor XIII-guided treatment algorithm reduces blood transfusion in burn surgery].

PubMed

Carneiro, João Miguel Gonçalves Valadares de Morais; Alves, Joana; Conde, Patrícia; Xambre, Fátima; Almeida, Emanuel; Marques, Céline; Luís, Mariana; Godinho, Ana Maria Mano Garção; Fernandez-Llimos, Fernando

Major burn surgery causes large hemorrhage and coagulation dysfunction. Treatment algorithms guided by ROTEM ® and factor VIIa reduce the need for blood products, but there is no evidence regarding factor XIII. Factor XIII deficiency changes clot stability and decreases wound healing. This study evaluates the efficacy and safety of factor XIII correction and its repercussion on transfusion requirements in burn surgery. Randomized retrospective study with 40 patients undergoing surgery at the Burn Unit, allocated into Group A those with factor XIII assessment (n = 20), and Group B, those without assessment (n = 20). Erythrocyte transfusion was guided by a hemoglobin trigger of 10g.dL -1 and the other blood products by routine coagulation and ROTEM ® tests. Analysis of blood product consumption included units of erythrocytes, fresh frozen plasma, platelets, and fibrinogen. The coagulation biomarker analysis compared the pre- and post-operative values. Group A (with factor XIII study) and Group B had identical total body surface area burned. All patients in Group A had a preoperative factor XIII deficiency, whose correction significantly reduced units of erythrocyte concentrate transfusion (1.95 vs. 4.05, p = 0.001). Pre- and post-operative coagulation biomarkers were similar between groups, revealing that routine coagulation tests did not identify factor XIII deficiency. There were no recorded thromboembolic events. Correction of factor XIII deficiency in burn surgery proved to be safe and effective for reducing perioperative transfusion of erythrocyte units. Copyright © 2017 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Factor XI and XII as antithrombotic targets.

PubMed

Müller, Felicitas; Gailani, David; Renné, Thomas

2011-09-01

Arterial and venous thrombosis are major causes of morbidity and mortality, and the incidence of thromboembolic diseases increases as a population ages. Thrombi are formed by activated platelets and fibrin. The latter is a product of the plasma coagulation system. Currently available anticoagulants such as heparins, vitamin K antagonists and inhibitors of thrombin or factor Xa target enzymes of the coagulation cascade that are critical for fibrin formation. However, fibrin is also necessary for terminating blood loss at sites of vascular injury. As a result, anticoagulants currently in clinical use increase the risk of bleeding, partially offsetting the benefits of reduced thrombosis. This review focuses on new targets for anticoagulation that are associated with minimal or no therapy-associated increased bleeding. Data from experimental models using mice and clinical studies of patients with hereditary deficiencies of coagulation factors XI or XII have shown that both of these clotting factors are important for thrombosis, while having minor or no apparent roles in processes that terminate blood loss (hemostasis). Hereditary deficiency of factor XII (Hageman factor) or factor XI, plasma proteases that initiate the intrinsic pathway of coagulation, impairs thrombus formation and provides protection from vascular occlusive events, while having a minimal impact on hemostasis. As the factor XII-factor XI pathway contributes to thrombus formation to a greater extent than to normal hemostasis, pharmacological inhibition of these coagulation factors may offer the exciting possibility of anticoagulation therapies with minimal or no bleeding risk.

Anomalous coagulation factors in non-arteritic anterior ischemic optic neuropathy with central retinal vein occlusion: A case report.

PubMed

Kim, Ji Hong; Kang, Min Ho; Seong, Mincheol; Cho, Heeyoon; Shin, Yong Un

2018-04-01

Non-arteritic anterior ischemic optic neuropathy (NAION) is characterized by sudden, painless visual loss and optic disc edema. NAION occurs mainly in the presence of cardiovascular disease and hypercoagulability, mainly in patients over 50 years of age. We experienced a case of NAION associated with central retinal vein occlusion (CRVO) in a young man with no underlying disease. A 46-year-old man was referred to our clinic following a sudden loss of vision in his right eye. The patient exhibited no underlying disease and reported no ongoing medication. Significant visual loss and visual disturbance of the right eye were observed. The pupil of the right eye was enlarged and an afferent pupillary defect was observed. On fundus examination, retinal hemorrhage was observed in the peripheral retina; macular edema was observed in optical coherence tomography analysis. However, optic disc edema was not evident. No abnormal findings were found in routine blood tests for hypercoagulability. After 3 days of steroid intravenous injection, macular edema disappeared and visual acuity was improved, but optic disc edema began to appear. One week later, optic disc edema was evident and visual acuity was significantly reduced; thus, the patient was diagnosed with NAION. In fluorescein angiography, peripheral retinal ischemia was observed, suggesting that CRVO was complicated. Blood tests, including analysis of coagulation factors, were performed again, showing that coagulation factors IX and XI were increased. Anomalous coagulation factors in non-arteritic anterior ischemic optic neuropathy with central retinal vein occlusion. Systemic steroids were administered. One month later, optic disc edema and retinal hemorrhage gradually diminished and eventually disappeared; however, visual acuity did not recover. In young patients without underlying disease, cases of NAION require careful screening for coagulation disorders. Even if there is no abnormality in the test for routine coagulation status, it may be necessary to confirm a coagulation defect through an additional coagulation factor assay.

Upregulation of the coagulation factor VII gene during glucose deprivation is mediated by activating transcription factor 4.

PubMed

Cronin, Katherine R; Mangan, Thomas P; Carew, Josephine A

2012-01-01

Constitutive production of blood coagulation proteins by hepatocytes is necessary for hemostasis. Stressful conditions trigger adaptive cellular responses and delay processing of most proteins, potentially affecting plasma levels of proteins secreted exclusively by hepatocytes. We examined the effect of glucose deprivation on expression of coagulation proteins by the human hepatoma cell line, HepG2. Expression of coagulation factor VII, which is required for initiation of blood coagulation, was elevated by glucose deprivation, while expression of other coagulation proteins decreased. Realtime PCR and ELISA demonstrated that the relative percentage expression +/- SD of steady-state F7 mRNA and secreted factor VII antigen were significantly increased (from 100+/-15% to 188+/-27% and 100+/-8.8% to 176.3+/-17.3% respectively, p<0.001) at 24 hr of treatment. The integrated stress response was induced, as indicated by upregulation of transcription factor ATF4 and of additional stress-responsive genes. Small interfering RNAs directed against ATF4 potently reduced basal F7 expression, and prevented F7 upregulation by glucose deprivation. The response of the endogenous F7 gene was replicated in reporter gene assays, which further indicated that ATF4 effects were mediated via interaction with an amino acid response element in the F7 promoter. Our data indicated that glucose deprivation enhanced F7 expression in a mechanism reliant on prior ATF4 upregulation primarily due to increased transcription from the ATF4 gene. Of five coagulation protein genes examined, only F7 was upregulated, suggesting that its functions may be important in a systemic response to glucose deprivation stress.

Upregulation of the Coagulation Factor VII Gene during Glucose Deprivation Is Mediated by Activating Transcription Factor 4

PubMed Central

Cronin, Katherine R.; Mangan, Thomas P.; Carew, Josephine A.

2012-01-01

Background Constitutive production of blood coagulation proteins by hepatocytes is necessary for hemostasis. Stressful conditions trigger adaptive cellular responses and delay processing of most proteins, potentially affecting plasma levels of proteins secreted exclusively by hepatocytes. We examined the effect of glucose deprivation on expression of coagulation proteins by the human hepatoma cell line, HepG2. Methodology/Principal Findings Expression of coagulation factor VII, which is required for initiation of blood coagulation, was elevated by glucose deprivation, while expression of other coagulation proteins decreased. Realtime PCR and ELISA demonstrated that the relative percentage expression +/− SD of steady-state F7 mRNA and secreted factor VII antigen were significantly increased (from 100+/−15% to 188+/−27% and 100+/−8.8% to 176.3+/−17.3% respectively, p<0.001) at 24 hr of treatment. The integrated stress response was induced, as indicated by upregulation of transcription factor ATF4 and of additional stress-responsive genes. Small interfering RNAs directed against ATF4 potently reduced basal F7 expression, and prevented F7 upregulation by glucose deprivation. The response of the endogenous F7 gene was replicated in reporter gene assays, which further indicated that ATF4 effects were mediated via interaction with an amino acid response element in the F7 promoter. Conclusions/Significance Our data indicated that glucose deprivation enhanced F7 expression in a mechanism reliant on prior ATF4 upregulation primarily due to increased transcription from the ATF4 gene. Of five coagulation protein genes examined, only F7 was upregulated, suggesting that its functions may be important in a systemic response to glucose deprivation stress. PMID:22848420

The story of a unique molecule in hemophilia A: recombinant single-chain factor VIII.

PubMed

Pabinger-Fasching, Ingrid

2016-05-01

For patients with hemophilia A, replacement of deficient factor VIII (FVIII) using plasma-derived or recombinant FVIII (rFVIII) products to restore hemostatic control can reduce bleeding complications and preserve musculoskeletal function. Despite the clinical availability of several of these products, challenges remain in the treatment of hemophilia A, the most notable of which are the risk of inhibitor development and the limited half-life of existing FVIII concentrates, which can make prophylaxis burdensome for patients. The use of recombinant protein technology may lead to novel FVIII products with improved properties. This article describes the story of a unique recombinant FVIII protein, rVIII-SingleChain, which is currently in development. In contrast to native FVIII and other commercially available rFVIII preparations, rVIII-SingleChain uses a strong, covalent bond to connect the light and heavy chains, thereby creating a stable, single-chain rFVIII. It has enhanced intrinsic stability, better integrity after reconstitution, and a higher binding affinity to von Willebrand factor. The physicochemical profile of rVIII-SingleChain and preclinical data on its activity and phamacokinetics strengthened the rationale for its clinical investigation. Available data from the AFFINITY clinical trial program are promising; indicating that it has good hemostatic efficacy when used on demand, for prophylaxis, and in the surgical setting, and is also very well tolerated. A pediatric study and an extension study are ongoing as part of the AFFINITY program. © 2016 Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Impact on hepatic estrogen-sensitive proteins by a 1-year contraceptive vaginal ring delivering Nestorone® and ethinyl estradiol.

PubMed

Archer, D F; Thomas, M A; Conard, J; Merkatz, R B; Creasy, G W; Roberts, K; Plagianos, M; Blithe, D; Sitruk-Ware, R

2016-01-01

Estrogen-sensitive hepatic proteins were assessed in women using a contraceptive vaginal ring (CVR) delivering 150mcg Nestorone® (NES) and 15mcg ethinyl estradiol (EE). A substudy of the Contraceptive Clinical Trials Network of the National Institute of Child Health and Human Development enrolled 129 participants, with assessments of factor VIII, fibrinogen, protein S (PS) and sex hormone binding globulin (SHBG). Thirty-six participants had used combined hormonal contraceptives (CHCs) in the cycle preceding first CVR use (recent users) and 70 had no history of recent use (nonusers). Mean values at baseline were within the normal range for all four proteins but were higher for factor VIII, fibrinogen and SHBG and significantly lower for PS in recent compared to nonusers. During NES/EE CVR use, factor VIII, fibrinogen and PS were within the normal range; however, SHBG levels were increased by nearly 100% at Cycle 13. The change from baseline to final evaluation was statistically significant for all proteins in nonusers. The change in recent users was significant for factor VIII at Cycle 6 and for SHBG at Cycles 6 and 13, but not for PS or fibrinogen. NES/EE CVR for up to 13cycles was associated with changes from baseline in plasma levels of factor VIII, fibrinogen and PS that were within the normal range, with SHBG levels above the normal range by Cycle 6. Nonusers of CHC before CVR showed wider changes in values versus recent users whose baseline values were increased by previous EE exposure. Recent use of CHCs demonstrated significant changes in all four measured hepatic proteins at baseline compared to nonusers. Use of the NES/EE CVR further changed these hepatic protein markers, but values remained within the normal range. Prebaseline exposure to estrogen can obscure interpretation of hepatic proteins changes associated with a second CHC. Copyright © 2016 Elsevier Inc. All rights reserved.

Variation in baseline factor VIII concentration in a retrospective cohort of mild/moderate hemophilia A patients carrying identical F8 mutations.

PubMed

Loomans, J I; van Velzen, A S; Eckhardt, C L; Peters, M; Mäkipernaa, A; Holmstrom, M; Brons, P P; Dors, N; Haya, S; Voorberg, J; van der Bom, J G; Fijnvandraat, K

2017-02-01

Essentials Factor VIII levels vary in mild and moderate hemophilia A (MHA) patients with the same mutation. We aimed to estimate the variation and determinants of factor VIII levels among MHA patients. Age and genotype explain 59% of the observed inter-individual variation in factor VIII levels. Intra-individual variation accounted for 45% of the variation in the three largest mutation groups. Background The bleeding phenotype in patients with mild/moderate hemophilia A (MHA) is inversely associated with the residual plasma concentration of factor VIII (FVIII:C). Within a group of patients with the same F8 missense mutation, baseline FVIII:C may vary, because, in healthy individuals, von Willebrand factor (VWF) levels, ABO blood group and age are also known to influence baseline FVIII:C. Our understanding of the pathophysiologic process of the causative genetic event leading to reduced baseline FVIII:C in MHA patients is still limited. Objectives To estimate the variation and determinants of baseline FVIII:C among MHA patients with the same F8 missense mutation. Methods Three hundred and forty-six patients carrying mutations that were present in at least 10 patients in the cohort were selected from the INSIGHT and the RISE studies, which are cohort studies including data of 3534 MHA patients from Europe, Canada, and Australia. Baseline FVIII:C was measured with a one-stage clotting assay. We used Levene's test, univariate and multivariate linear regression, and mixed-model analyses. Results For 59% of patients, the observed variation in baseline FVIII:C was explained by age and genotype. Compared to FVIII:C in patients with Arg612Cys, FVIII:C was significantly different in patients with eight other F8 missense mutations. Intra-individual variation explained 45% of the observed variance in baseline FVIII:C among patients with the same mutation. Conclusion Our results indicate that baseline FVIII:C levels are not exclusively determined by F8 genotype in MHA patients. Insights into other factors may provide potential novel targets for the treatment of MHA. © 2016 International Society on Thrombosis and Haemostasis.

Coagulation factor Xa drives tumor cells into apoptosis through BH3-only protein Bim up-regulation

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

Borensztajn, Keren S.; Bijlsma, Maarten F.; Groot, Angelique P.

2007-07-15

Coagulation Factor (F)Xa is a serine protease that plays a crucial role during blood coagulation by converting prothrombin into active thrombin. Recently, however, it emerged that besides this role in coagulation, FXa induces intracellular signaling leading to different cellular effects. Here, we show that coagulation factor (F)Xa drives tumor cells of epithelial origin, but not endothelial cells or monocytes, into apoptosis, whereas it even enhances fibroblast survival. FXa signals through the protease activated receptor (PAR)-1 to activate extracellular-signal regulated kinase (ERK) 1/2 and p38. This activation is associated with phosphorylation of the transcription factor CREB, and in tumor cells withmore » up-regulation of the BH3-only pro-apoptotic protein Bim, leading to caspase-3 cleavage, the main hallmark of apoptosis. Transfection of tumor cells with dominant negative forms of CREB or siRNA for either PAR-1, Bim, ERK1 and/or p38 inhibited the pro-apoptotic effect of FXa. In fibroblasts, FXa-induced PAR-1 activation leads to down-regulation of Bim and pre-treatment with PAR-1 or Bim siRNA abolishes proliferation. We thus provide evidence that beyond its role in blood coagulation, FXa plays a key role in cellular processes in which Bim is the central player in determining cell survival.« less

Hepatic dysfunction contributes to coagulation disturbances in patients undergoing whole body hyperthermia by use of extracorporeal circulation.

PubMed

Worel, Nina; Knöbl, Paul; Karanikas, Georgios; Fuchs, Eva-Maria; Bojic, Andja; Brodowicz, Thomas; Jilma, Petra; Zielinski, Christoph C; Köstler, Wolfgang J; Locker, Gottfried J

2014-09-01

This phase I study was performed to evaluate coagulation alterations during extracorporeal circulation (ECC) induced whole body hyperthermia (WBHT) in 12 patients with advanced soft tissue sarcomas. To distinguish between effects of normothermic ECC and ECC-WBHT, blood samples were drawn at different time points: at baseline, after 30 min on normothermic ECC, at the end of the heating period, and 24 h and 7 days thereafter. Standard coagulation tests, coagulation factors, thrombelastography,platelets and reticulated platelets, liver enzymes, and scintigraphic platelet imaging were performed. Normothermic ECC resulted in coagulation alterations most likely due to systemic anticoagulation. Induction of hyperthermia caused thrombocytopenia, increased fibrin degradation products,prolonged clotting times, alteration in coagulation factors, and increased liver enzymes. The majority of these effects was most pronounced 24 h after ECC-WBHT. In addition, late liver sequestration of platelets was demonstrated in scintigraphic imaging at that time point. Temporal correlation between hemostatic alterations and elevation in liver enzymes leads to the assumption that liver impairment might play a crucial role in coagulation disturbances observed during ECC-WBHT and thereafter, thus strongly supported by liver sequestration of platelets.Therefore a close monitoring of hepatic derived coagulation alterations in patients undergoing extracorporeal whole body hypothermia is warranted.

Matriptase activation connects tissue factor-dependent coagulation initiation to epithelial proteolysis and signaling.

PubMed

Le Gall, Sylvain M; Szabo, Roman; Lee, Melody; Kirchhofer, Daniel; Craik, Charles S; Bugge, Thomas H; Camerer, Eric

2016-06-23

The coagulation cascade is designed to sense tissue injury by physical separation of the membrane-anchored cofactor tissue factor (TF) from inactive precursors of coagulation proteases circulating in plasma. Once TF on epithelial and other extravascular cells is exposed to plasma, sequential activation of coagulation proteases coordinates hemostasis and contributes to host defense and tissue repair. Membrane-anchored serine proteases (MASPs) play critical roles in the development and homeostasis of epithelial barrier tissues; how MASPs are activated in mature epithelia is unknown. We here report that proteases of the extrinsic pathway of blood coagulation transactivate the MASP matriptase, thus connecting coagulation initiation to epithelial proteolysis and signaling. Exposure of TF-expressing cells to factors (F) VIIa and Xa triggered the conversion of latent pro-matriptase to an active protease, which in turn cleaved the pericellular substrates protease-activated receptor-2 (PAR2) and pro-urokinase. An activation pathway-selective PAR2 mutant resistant to direct cleavage by TF:FVIIa and FXa was activated by these proteases when cells co-expressed pro-matriptase, and matriptase transactivation was necessary for efficient cleavage and activation of wild-type PAR2 by physiological concentrations of TF:FVIIa and FXa. The coagulation initiation complex induced rapid and prolonged enhancement of the barrier function of epithelial monolayers that was dependent on matriptase transactivation and PAR2 signaling. These observations suggest that the coagulation cascade engages matriptase to help coordinate epithelial defense and repair programs after injury or infection, and that matriptase may contribute to TF-driven pathogenesis in cancer and inflammation.

Elevated lipoprotein (a) levels are an independent risk factor for retinal vein occlusion.

PubMed

Kuhli-Hattenbach, Claudia; Miesbach, Wolfgang; Lüchtenberg, Marc; Kohnen, Thomas; Hattenbach, Lars-Olof

2017-03-01

To investigate the prevalence of lipoprotein (a) [Lp(a)] and other thrombophilic disorders among retinal vein occlusion (RVO) patients with regard to age and various risk factors. We retrospectively reviewed the medical records of 100 patients with central, hemicentral or branch RVO who had undergone routine thrombophilia screening. Data were compared with 100 controls. Both cohorts were divided into three subgroups (≤45 years, >45-≤60 years or >60 years), depending on the patients' age at the time of the RVO or a previous thromboembolic event. Elevated Lp(a) plasma levels were significantly more prevalent among RVO patients than among controls (p < 0.0001; OR: 4.8). Moreover, we determined age ≤60 years by the time of the first thromboembolic event as a strong predictor of elevated Lp(a) (p = 0.0002). The coincidence of elevated Lp(a) with other coagulation disorders further increased the OR for RVO to 9.3 (95% CI 2.1-41.8). Multivariate analysis revealed the presence of cardiovascular risk factors (OR: 3.1, p = 0.0004), elevated lipoprotein (a) levels (OR: 5.2, p = 0.0001) and increased factor VIII activity (OR: 5.9, p = 0.001) as independent risk factors for the development of RVO among patients. Our results indicate that elevated plasma levels of Lp(a) are associated with the development of RVO. Selective screening of young patients and subjects with a personal or family history of thromboembolism may be helpful in identifying RVO patients with elevated Lp(a). © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Shortened Lifespan and Lethal Hemorrhage in a Hemophilia A Mouse Model.

PubMed

Staber, Janice M; Pollpeter, Molly J

2016-01-01

Hemophilia A animal models have helped advance our understanding of factor VIII deficiency. Previously, factor VIII deficient mouse models were reported to have a normal life span without spontaneous bleeds. However, the bleeding frequency and survival in these animals has not been thoroughly evaluated. To investigate the survival and lethal bleeding frequency in two strains of E-16 hemophilia A mice. We prospectively studied factor VIII deficient hemizygous affected males (n = 83) and homozygous affected females (n = 55) for survival and bleeding frequency. Animals were evaluated for presence and location of bleeds as potential cause of death. Hemophilia A mice had a median survival of 254 days, which is significantly shortened compared to wild type controls (p < 0.0001). In addition, the hemophilia A mice experienced hemorrhage in several tissues. This previously-underappreciated shortened survival in the hemophilia A murine model provides new outcomes for investigation of therapeutics and also reflects the shortened lifespan of patients if left untreated.

Overview of the coagulation system.

PubMed

Palta, Sanjeev; Saroa, Richa; Palta, Anshu

2014-09-01

Coagulation is a dynamic process and the understanding of the blood coagulation system has evolved over the recent years in anaesthetic practice. Although the traditional classification of the coagulation system into extrinsic and intrinsic pathway is still valid, the newer insights into coagulation provide more authentic description of the same. Normal coagulation pathway represents a balance between the pro coagulant pathway that is responsible for clot formation and the mechanisms that inhibit the same beyond the injury site. Imbalance of the coagulation system may occur in the perioperative period or during critical illness, which may be secondary to numerous factors leading to a tendency of either thrombosis or bleeding. A systematic search of literature on PubMed with MeSH terms 'coagulation system, haemostasis and anaesthesia revealed twenty eight related clinical trials and review articles in last 10 years. Since the balance of the coagulation system may tilt towards bleeding and thrombosis in many situations, it is mandatory for the clinicians to understand physiologic basis of haemostasis in order to diagnose and manage the abnormalities of the coagulation process and to interpret the diagnostic tests done for the same.

Overview of the coagulation system

PubMed Central

Palta, Sanjeev; Saroa, Richa; Palta, Anshu

2014-01-01

Coagulation is a dynamic process and the understanding of the blood coagulation system has evolved over the recent years in anaesthetic practice. Although the traditional classification of the coagulation system into extrinsic and intrinsic pathway is still valid, the newer insights into coagulation provide more authentic description of the same. Normal coagulation pathway represents a balance between the pro coagulant pathway that is responsible for clot formation and the mechanisms that inhibit the same beyond the injury site. Imbalance of the coagulation system may occur in the perioperative period or during critical illness, which may be secondary to numerous factors leading to a tendency of either thrombosis or bleeding. A systematic search of literature on PubMed with MeSH terms ‘coagulation system, haemostasis and anaesthesia revealed twenty eight related clinical trials and review articles in last 10 years. Since the balance of the coagulation system may tilt towards bleeding and thrombosis in many situations, it is mandatory for the clinicians to understand physiologic basis of haemostasis in order to diagnose and manage the abnormalities of the coagulation process and to interpret the diagnostic tests done for the same. PMID:25535411

Tissue Factor Coagulant Activity is Regulated by the Plasma Membrane Microenvironment.

PubMed

Yu, Yuanjie; Böing, Anita N; Hau, Chi M; Hajji, Najat; Ruf, Wolfram; Sturk, Auguste; Nieuwland, Rienk

2018-06-01

 Tissue factor (TF) can be present in a non-coagulant and coagulant form. Whether the coagulant activity is affected by the plasma membrane microenvironment is unexplored.  This article studies the presence and coagulant activity of human TF in plasma membrane micro-domains.  Plasma membranes were isolated from human MIA PaCa2 cells, MDA-MB-231 cells and human vascular smooth muscle cells by Percoll gradient ultracentrifugation after cell disruption. Plasma membranes were fractionated by OptiPrep gradient ultracentrifugation, and the presence of TF, flotillin, caveolin, clathrin, protein disulphide isomerase (PDI), TF pathway inhibitor (TFPI) and phosphatidylserine (PS) were determined.  Plasma membranes contain two detergent-resistant membrane (DRM) compartments differing in density and biochemical composition. High-density DRMs (DRM-H) have a density ( ρ ) of 1.15 to 1.20 g/mL and contain clathrin, whereas low-density DRMs (DRM-L) have a density between 1.09 and 1.13 g/mL and do not contain clathrin. Both DRMs contain TF, flotillin and caveolin. PDI is detectable in DRM-H, TFPI is not detectable in either DMR-H or DRM-L and PS is detectable in DRM-L. The DRM-H-associated TF (> 95% of the TF antigen) lacks detectable coagulant activity, whereas the DRM-L-associated TF triggers coagulation. This coagulant activity is inhibited by lactadherin and thus PS-dependent, but seemed insensitive to 16F16, an inhibitor of PDI.  Non-coagulant and coagulant TF are present within different types of DRMs in the plasma membrane, and the composition of these DRMs may affect the TF coagulant activity. Schattauer GmbH Stuttgart.

[Influencing factors and mechanism of arsenic removal during the aluminum coagulation process].

PubMed

Chen, Gui-Xia; Hu, Cheng-Zhi; Zhu, Ling-Feng; Tong, Hua-Qing

2013-04-01

Aluminum coagulants are widely used in arsenic (As) removal during the drinking water treatment process. Aluminium chloride (AlCl3) and polyaluminium chloride (PACl) which contains high content of Al13 were used as coagulants. The effects of aluminum species, pH, humic acid (HA) and coexisting anions on arsenic removal were investigated. Results showed that AlCl3 and PACl were almost ineffective in As(II) removal while the As(V) removal efficiency reached almost 100%. pH was an important influencing factor on the arsenic removal efficiency, because pH influenced the distribution of aluminum species during the coagulation process. The efficiency of arsenic removal by aluminum coagulants was positively correlated with the content of Al13 species. HA and some coexisting anions showed negative impact on arsenic removal because of the competitive adsorption. The negative influence of HA was more pronounced at low coagulant dosages. PO4(3-) and F(-) showed marked influence during arsenic removal, but there was no obvious influence when SiO3(2-), CO3(2-) and SO4(2-) coexisted. The present study would be helpful to direct arsenic removal by enhanced coagulation during the drinking water treatment.

EXTRINSIC COAGULATION BLOCKADE ATTENUATES LUNG INJURY AND PROINFLAMMATORY CYTOKINE RELEASE AFTER INTRATRACHEAL LIPOPOLYSACCHARIDE

EPA Science Inventory

Initiation of coagulation by tissue factor (TF) is a potentially powerful regulator of local inflammatory responses. We hypothesized that blockade of TF-factor VIIa (FVIIa) complex would decrease lung inflammation and proinflammatory cytokine release after tracheal instillation o...

Effects of alum coagulation on speciation and distribution of trihalomethanes (THMs) and haloacetic acids (HAAs).

PubMed

Gang, Dianchen; Clevenger, Thomas E; Banerji, Shankha K

2005-01-01

The impacts of alum coagulation on the distribution of disinfection by-products (DBPs), trihalomethanes (THMs), and haloacetic acids (HAAs) were evaluated under controlled chlorination conditions using four surface waters. Among the nine HAAs found in waters, dihaloacetic acids (X2AAs) have been found to be the dominant species in all of the raw and alum treated waters. Alum coagulation tends to remove more monohaloacetic acids (XAAs) and trihaloacetic acids (X3AAs) precursors than that of dihaloacetic acids (X2AAs). Alum coagulation treated water had a lower HAA9/TTHM ratio compared with that of the raw water. The increase of THM bromine incorporation factors (BIFalpha) value of alum treated water was statistically significant in comparison with the raw water. On average, BIFalpha increased by 54% after the alum coagulation process in these four different waters. This indicated that THM speciations shifted in favor of the more brominated compounds. However, alum coagulation treatment process had less effect on HAA bromi ne incorporation factors (BIFbeta)than it did on BIFalpha. Bromine incorporation factor (BIF) values decreased with time in the THM and HAA formation processes, especially within the first 10 h of the reaction time. This suggested that brominated THMs or HAAs formed faster than the chlorinated species in the initial period.

HEPATIC FUNCTION AFTER GENETICALLY-ENGINEERED PIG LIVER TRANSPLANTATION IN BABOONS

PubMed Central

Ekser, Burcin; Echeverri, Gabriel J.; Hassett, Andrea Cortese; Yazer, Mark H.; Long, Cassandra; Meyer, Michael; Ezzelarab, Mohamed; Lin, Chih Che; Hara, Hidetaka; van der Windt, Dirk J.; Dons, Eefje M.; Phelps, Carol; Ayares, David; Cooper, David K.C.; Gridelli, Bruno

2010-01-01

Background If ‘bridging’ to allotransplantation is to be achieved by a pig liver xenograft, adequate hepatic function needs to be assured. Methods We have studied hepatic function in baboons after transplantation of livers from α1,3-galactosyltransferase gene-knockout (GTKO,n=1) or GTKO pigs transgenic for CD46 (GTKO/CD46,n=5). Monitoring was by liver function tests and coagulation parameters. Pig-specific proteins in the baboon serum/plasma were identified by Western blot. In 4 baboons, coagulation factors were measured. The results were compared with values from healthy humans, baboons, and pigs. Results Recipient baboons died or were euthanized after 4-7 days following internal bleeding associated with profound thrombocytopenia. However, parameters of liver function, including coagulation, remained in the near-normal range, except for some cholestasis. Western blot demonstrated that pig proteins (albumin, fibrinogen, haptoglobin, plasminogen) were produced by the liver from day 1. Production of several pig coagulation factors was confirmed. Conclusions After the transplantation of genetically-engineered pig livers into baboons (1) many parameters of hepatic function, including coagulation, were normal or near-normal; (2) there was evidence for production of pig proteins, including coagulation factors, and (3) these appeared to function adequately in baboons, though inter-species compatibility of such proteins remains to be confirmed. PMID:20606605

Mannose-binding lectin and its associated proteases (MASPs) mediate coagulation and its deficiency is a risk factor in developing complications from infection, including disseminated intravascular coagulation

PubMed Central

Takahashi, Kazue; Chang, Wei-Chuan; Takahashi, Minoru; Pavlov, Vasile; Ishida, Yumi; La Bonte, Laura; Shi, Lei; Fujita, Teizo; Stahl, Gregory L.; Van Cott, Elizabeth M.

2010-01-01

The first line of host defense is the innate immune system that includes coagulation factors and pattern recognition molecules, one of which is mannose-binding lectin (MBL). Previous studies have demonstrated that MBL deficiency increases susceptibility to infection. Several mechanisms are associated with increased susceptibility to infection, including reduced opsonophagocytic killing and reduced lectin complement pathway activation. In this study, we demonstrate that MBL and MBL-associated serine protease (MASP)-1/3 together mediate coagulation factor-like activities, including thrombin-like activity. MBL and/or MASP-1/3 deficient hosts demonstrate in vivo evidence that MBL and MASP-1/3 are involved with hemostasis following injury. Staphylococcus aureus infected MBL null mice developed disseminated intravascular coagulation (DIC), which was associated with elevated blood IL-6 levels (but not TNF-α and multi-organ inflammatory responses). Infected MBL null mice also develop liver injury. These findings suggest that MBL deficiency may manifest into DIC and organ failure during infectious diseases. PMID:20399528

Influence of blood lipids on global coagulation test results.

PubMed

Kim, Jung-Ah; Kim, Ji-Eun; Song, Sang Hoon; Kim, Hyun Kyung

2015-01-01

High levels of blood lipids have been associated with high levels of coagulation factors. We investigated whether blood lipids influence the results of global coagulation tests, including prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin generation assay (TGA). PT, aPTT, and TGA, along with procoagulant and anticoagulant factors, were measured in 488 normal individuals. Vitamin K status was assessed with prothrombin-induced by vitamin K absence-II (PIVKA-II). The procoagulant factors II, VII, IX, X, and XI and anticoagulant factors protein C and protein S showed significant correlations with triglyceride, and the procoagulant factors II, V, VII, IX, X, XI, and XII and anticoagulant factors antithrombin and protein C correlated with total cholesterol. There were no correlations of blood lipid levels with PIVKA-II levels. Subjects with high triglyceride levels (≥200 mg/dL) showed shorter PT values than those with lower triglyceride levels. However, aPTT value was not changed in terms of blood lipid levels. In both 1 and 5 pM tissue factor-induced TGAs, subjects in the high-triglyceride or high-cholesterol groups (≥240 mg/dL) had high levels of lag time, time-to-peak, and endogenous thrombin potential. Total cholesterol was a significant determinant of PT and TGA values. High blood lipids were related with increased coagulation activity in a normal population. Our findings are expected to help interpret the global coagulation test results in individuals with high lipid levels.

Influence of Blood Lipids on Global Coagulation Test Results

PubMed Central

Kim, Jung-Ah; Kim, Ji-Eun; Song, Sang Hoon

2015-01-01

Background High levels of blood lipids have been associated with high levels of coagulation factors. We investigated whether blood lipids influence the results of global coagulation tests, including prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin generation assay (TGA). Methods PT, aPTT, and TGA, along with procoagulant and anticoagulant factors, were measured in 488 normal individuals. Vitamin K status was assessed with prothrombin-induced by vitamin K absence-II (PIVKA-II). Results The procoagulant factors II, VII, IX, X, and XI and anticoagulant factors protein C and protein S showed significant correlations with triglyceride, and the procoagulant factors II, V, VII, IX, X, XI, and XII and anticoagulant factors antithrombin and protein C correlated with total cholesterol. There were no correlations of blood lipid levels with PIVKA-II levels. Subjects with high triglyceride levels (≥200 mg/dL) showed shorter PT values than those with lower triglyceride levels. However, aPTT value was not changed in terms of blood lipid levels. In both 1 and 5 pM tissue factor-induced TGAs, subjects in the high-triglyceride or high-cholesterol groups (≥240 mg/dL) had high levels of lag time, time-to-peak, and endogenous thrombin potential. Total cholesterol was a significant determinant of PT and TGA values. Conclusion High blood lipids were related with increased coagulation activity in a normal population. Our findings are expected to help interpret the global coagulation test results in individuals with high lipid levels. PMID:25553275

Honey Bee Venom (Apis mellifera) Contains Anticoagulation Factors and Increases the Blood-clotting Time.

PubMed

Zolfagharian, Hossein; Mohajeri, Mohammad; Babaie, Mahdi

2015-12-01

Bee venom (BV) is a complex mixture of proteins and contains proteins such as phospholipase and melittin, which have an effect on blood clotting and blood clots. The mechanism of action of honey bee venom (HBV, Apis mellifera) on human plasma proteins and its anti-thrombotic effect were studied. The purpose of this study was to investigate the anti-coagulation effect of BV and its effects on blood coagulation and purification. Crude venom obtained from Apis mellifera was selected. The anti-coagulation factor of the crude venom from this species was purified by using gel filtration chromatography (sephadex G-50), and the molecular weights of the anti-coagulants in this venom estimated by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Blood samples were obtained from 10 rabbits, and the prothrombin time (PT) and the partial thromboplastin time (PTT) tests were conducted. The approximate lethal dose (LD) values of BV were determined. Crude BV increased the blood clotting time. For BV concentrations from 1 to 4 mg/mL, clotting was not observed even at more than 300 seconds, standard deviations (SDs) = ± 0.71; however, clotting was observed in the control group 13.8 s, SDs = ± 0.52. Thus, BV can be considered as containing anti-coagulation factors. Crude BV is composed 4 protein bands with molecular weights of 3, 15, 20 and 41 kilodalton (kDa), respectively. The LD50 of the crude BV was found to be 177.8 μg/mouse. BV contains anti-coagulation factors. The fraction extracted from the Iranian bees contains proteins that are similar to anti-coagulation proteins, such as phospholipase A2 (PLA2) and melittin, and that can increase the blood clotting times in vitro.

Honey Bee Venom (Apis mellifera) Contains Anticoagulation Factors and Increases the Blood-clotting Time

PubMed Central

Zolfagharian, Hossein; Mohajeri, Mohammad; Babaie, Mahdi

2015-01-01

Objectives: Bee venom (BV) is a complex mixture of proteins and contains proteins such as phospholipase and melittin, which have an effect on blood clotting and blood clots. The mechanism of action of honey bee venom (HBV, Apis mellifera) on human plasma proteins and its anti-thrombotic effect were studied. The purpose of this study was to investigate the anti-coagulation effect of BV and its effects on blood coagulation and purification. Methods: Crude venom obtained from Apis mellifera was selected. The anti-coagulation factor of the crude venom from this species was purified by using gel filtration chromatography (sephadex G-50), and the molecular weights of the anti-coagulants in this venom estimated by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Blood samples were obtained from 10 rabbits, and the prothrombin time (PT) and the partial thromboplastin time (PTT) tests were conducted. The approximate lethal dose (LD) values of BV were determined. Results: Crude BV increased the blood clotting time. For BV concentrations from 1 to 4 mg/mL, clotting was not observed even at more than 300 seconds, standard deviations (SDs) = ± 0.71; however, clotting was observed in the control group 13.8 s, SDs = ± 0.52. Thus, BV can be considered as containing anti-coagulation factors. Crude BV is composed 4 protein bands with molecular weights of 3, 15, 20 and 41 kilodalton (kDa), respectively. The LD50 of the crude BV was found to be 177.8 μg/mouse. Conclusion: BV contains anti-coagulation factors. The fraction extracted from the Iranian bees contains proteins that are similar to anti-coagulation proteins, such as phospholipase A2 (PLA2) and melittin, and that can increase the blood clotting times in vitro. PMID:26998384

Pilot testing of dissolved air flotation (DAF) in a highly effective coagulation-flocculation integrated (FRD) system.

PubMed

Wang, Yili; Guo, Jinlong; Tang, Hongxiao

2002-01-01

Factors of pretreatment coagulation/flocculation units were studied using raw water of low temperature and low turbidity. Aluminum sulfate (AS) and selected polyaluminium chlorides (PACls) were all effective in the DAF process when used under favorable conditions of coagulant addition, coagulation, flocculation and flotation units. Compared with the AS coagulant, PACls, at lower dosage, could give the same effective performance even with shorter coagulation/flocculation time or lower recycle ratio during the treatment of cold water. This is attributed to the higher-charged polymeric Al species, and the lower hydrophilic and more compact flocculated flocs of PACl coagulant. Based on results of pilot experiments, the goal of FRD system can be achieved by combining a DAF heterocoagulation reactor with PACl coagulant (F), an efficient flocculation reactor (R), as well as an economical auto-dosing system (D).

International recommendations on the diagnosis and treatment of patients with acquired hemophilia A

PubMed Central

Huth-Kühne, Angela; Baudo, Francesco; Collins, Peter; Ingerslev, Jørgen; Kessler, Craig M.; Lévesque, Hervé; Castellano, Maria Eva Mingot; Shima, Midori; St-Louis, Jean

2009-01-01

Acquired hemophilia A (AHA) is a rare bleeding disorder characterized by autoantibodies directed against circulating coagulation factor (F) VIII. Typically, patients with no prior history of a bleeding disorder present with spontaneous bleeding and an isolated prolonged aPTT. AHA may, however, present without any bleeding symptoms, therefore an isolated prolonged aPTT should always be investigated further irrespective of the clinical findings. Control of acute bleeding is the first priority, and we recommend first-line therapy with bypassing agents such as recombinant activated FVII or activated prothrombin complex concentrate. Once the diagnosis has been achieved, immediate autoantibody eradication to reduce subsequent bleeding risk should be performed. We recommend initial treatment with corticosteroids or combination therapy with corticosteroids and cyclophosphamide and suggest second-line therapy with rituximab if first-line therapy fails or is contraindicated. In contrast to congenital hemophilia, no comparative studies exist to support treatment recommendations for patients with AHA, therefore treatment guidance must rely on the expertise and clinical experience of specialists in the field. The aim of this document is to provide a set of international practice guidelines based on our collective clinical experience in treating patients with AHA and contribute to improved care for this patient group. PMID:19336751

NE VIII lambda 774 and time variable associated absorption in the QSO UM 675

NASA Technical Reports Server (NTRS)

Hamann, Fred; Barlow, Thomas A.; Beaver, E. A.; Burbidge, E. M.; Cohen, Ross D.; Junkkarinen, Vesa; Lyons, R.

1995-01-01

We discuss measurements of Ne VIII lambda 774 absorption and the time variability of other lines in the z(sub a) approximately equal z(sub e) absorption system of the z(sub e) = 2.15 QSO UM 675 (0150-203). The C IV lambda 1549 and N V 1240 doublets at z(sub a) = 2.1340 (shifted approximately 1500 km/s from z(sub e) strengthened by a factor of approximately 3 between observations by Sargent, Boksenberg and Steidel (1981 November) and our earliest measurements (1990 November and December). We have no information on changes in other z(sub a) approximately equal z(sub e) absorption lines. Continued monitoring since 1990 November shows no clear changes in any of the absorptions between approximately 1100 and 1640 A rest. The short timescale of the variability (less than or approximately equal to 2.9 yr rest) strongly suggests that the clouds are dense, compact, close to the QSO, and photoionized by the QSO continuum. If the line variability is caused by changes in the ionization, the timescale requires densities greater than approximately 4000/cu cm. Photoionization calculations place the absorbing clouds within approximately 200 pc of the continuum source. The full range of line ionizations (from Ne VIII lambda 774 to C III lambda 977) in optically thin gas (no Lyman limit) implies that the absorbing regions span a factor of more than approximately 10 in distance or approximately 100 in density. Across these regions, the total hydrogen (H I + H II) column ranges from a few times 10(exp 18)/sq cm in the low-ionization gas to approximately 10(exp 20)/sq cm where the Ne VIII doublet forms. The metallicity is roughly solar or higher, with nitrogen possibly more enhanced by factors of a few. The clouds might contribute significant line emission if they nearly envelop the QSO. The presence of highly ionized Ne VIII lambda 774 absorption near the QSO supports recent studies that link z(sub a) approximately equal to z(sub e) systems with X-ray 'wamr absorbers. We show that the Ne VIII absorbing gas would itself produce measurable warm absorption -- characterized by bound-free O VII or O VIII edegs near 0.8 keV -- if the column densities were N(sub H) greater than or approximately equal to 10(exp 21)/sq cm (for solar abundances).

NE VIII lambda 774 and time variable associated absorption in the QSO UM 675

NASA Astrophysics Data System (ADS)

Hamann, Fred; Barlow, Thomas A.; Beaver, E. A.; Burbidge, E. M.; Cohen, Ross D.; Junkkarinen, Vesa; Lyons, R.

1995-04-01

We discuss measurements of Ne VIII lambda 774 absorption and the time variability of other lines in the za approximately equal ze absorption system of the ze = 2.15 QSO UM 675 (0150-203). The C IV lambda 1549 and N V 1240 doublets at za = 2.1340 (shifted approximately 1500 km/s from ze strengthened by a factor of approximately 3 between observations by Sargent, Boksenberg and Steidel (1981 November) and our earliest measurements (1990 November and December). We have no information on changes in other za approximately equal ze absorption lines. Continued monitoring since 1990 November shows no clear changes in any of the absorptions between approximately 1100 and 1640 A rest. The short timescale of the variability (less than or approximately equal to 2.9 yr rest) strongly suggests that the clouds are dense, compact, close to the QSO, and photoionized by the QSO continuum. If the line variability is caused by changes in the ionization, the timescale requires densities greater than approximately 4000/cu cm. Photoionization calculations place the absorbing clouds within approximately 200 pc of the continuum source. The full range of line ionizations (from Ne VIII lambda 774 to C III lambda 977) in optically thin gas (no Lyman limit) implies that the absorbing regions span a factor of more than approximately 10 in distance or approximately 100 in density. Across these regions, the total hydrogen (H I + H II) column ranges from a few times 1018/sq cm in the low-ionization gas to approximately 1020/sq cm where the Ne VIII doublet forms. The metallicity is roughly solar or higher, with nitrogen possibly more enhanced by factors of a few. The clouds might contribute significant line emission if they nearly envelop the QSO. The presence of highly ionized Ne VIII lambda 774 absorption near the QSO supports recent studies that link za approximately equal to ze systems with X-ray 'wamr absorbers. We show that the Ne VIII absorbing gas would itself produce measurable warm absorption -- characterized by bound-free O VII or O VIII edegs near 0.8 keV -- if the column densities were NH greater than or approximately equal to 1021/sq cm (for solar abundances).

Heckathorn's disease: variable functional dificiency of antihemophilic factor (factor VIII).

PubMed

Ratnoff, O D; Lewis, J H

1975-08-01

A family is described in which a syndrome resembling moderately severe classic hemophilia was apparently inherited as an X chromosome-linked trait. In two affected individuals, the titer of functional antihemophilic factor varied dramatically from time to time, while the conversion of prothrombin to thrombin was impaired in no apparent relationship to AHF functional activity. A transfusion of 200 ml of fresh-frozen plasma did not correct the serum prothrombin times in either patient. In vitro, the additions of 10% of normal plasma or serum or washed plain or frozen platelets also did not normalize the serum prothrombin times. No inhibitor could be demonstrated in the blood of either patient. In one patient, RH, dissipation of infused cryoprecipitated AHF was abnormally slow, and, after an intensive course of transfusion of cryoprecipitate and whole blood, the titer of functional AHF remained at normal levels for at least 1 wk. The plasma of RH inhibited a human antibody against AHF in proportion to its titer of functional AHF (i.e., the defect was CRM-) despite the presence of relatively greater amounts of antigenic material recognized by heterologous antiserum. No qualitative abnormality of the AHF-like material in RH's plasma was identified. Inheritance of the abnormality appears superficially to be X chromosome-linked; on this assumption, three of four obligate carriers of the disorder were recognized by the presence of excess amounts of AHF-like antigens relative to AHF functional activity. This coagulation disorder has been designated Heckathorn's disease and may presage the discovery of other examples of hemophilia-related syndromes.

The Intrinsic Pathway of Coagulation as a Target for Antithrombotic Therapy

PubMed Central

Wheeler, Allison P.; Gailani, David

2016-01-01

Plasma coagulation in the activated partial thromboplastin time assay is initiated by sequential activation of coagulation factors XII, XI and IX – the classical intrinsic pathway of coagulation. It is well recognized that this series of proteolytic reactions is not an accurate model for hemostasis in vivo, as factor XII deficiency does not cause abnormal bleeding, and fXI deficiency causes a relatively mild propensity to bleed excessively with injury. Despite their limited roles in hemostasis, there is mounting evidence that fXI and fXII contribute to thrombosis, and that inhibiting them can produce an antithrombotic effect with a relatively small effect on hemostasis. In this chapter the contributions of components of the intrinsic pathway to thrombosis in animal models and humans are discussed, and results of early clinical trials of drugs targeting factors IX, XI and XII are presented. PMID:27637310

Differential procoagulant activity of microparticles derived from monocytes, granulocytes, platelets and endothelial cells: impact of active tissue factor.

PubMed

Shustova, Olga N; Antonova, Olga A; Golubeva, Nina V; Khaspekova, Svetlana G; Yakushkin, Vladimir V; Aksuk, Svetlana A; Alchinova, Irina B; Karganov, Mikhail Y; Mazurov, Alexey V

2017-07-01

: Microparticles released by activated/apoptotic cells exhibit coagulation activity as they express phosphatidylserine and some of them - tissue factor. We compared procoagulant properties of microparticles from monocytes, granulocytes, platelets and endothelial cells and assessed the impact of tissue factor in observed differences. Microparticles were sedimented (20 000g, 30 min) from the supernatants of activated monocytes, monocytic THP-1 cells, granulocytes, platelets and endothelial cells. Coagulation activity of microparticles was examined using plasma recalcification assay. The size of microparticles was evaluated by dynamic light scattering. Tissue factor activity was measured by its ability to activate factor X. All microparticles significantly accelerated plasma coagulation with the shortest lag times for microparticles derived from monocytes, intermediate - for microparticles from THP-1 cells and endothelial cells, and the longest - for microparticles from granulocytes and platelets. Average diameters of microparticles ranged within 400-600 nm. The largest microparticles were produced by endothelial cells and granulocytes, smaller - by monocytes, and the smallest - by THP-1 cells and platelets. The highest tissue factor activity was detected in microparticles from monocytes, lower activity - in microparticles from endothelial cells and THP-1 cells, and no activity - in microparticles from platelets and granulocytes. Anti-tissue factor antibodies extended coagulation lag times for microparticles from monocytes, endothelial cells and THP-1 cells and equalized them with those for microparticles from platelets and granulocytes. Higher coagulation activity of microparticles from monocytes, THP-1 cells and endothelial cells in comparison with microparticles from platelets and granulocytes is determined mainly by the presence of active tissue factor.

Kreuth IV: European consensus proposals for treatment of haemophilia with coagulation factor concentrates.

PubMed

Giangrande, P L F; Peyvandi, F; O'Mahony, B; Behr-Gross, M-E; Hilger, A; Schramm, W; Mannucci, P M

2017-05-01

This report summarizes recommendations relating to haemophilia therapy arising from discussions among experts from 36 European countries during the 'Kreuth IV' meeting in May 2016. The objective of the meeting was for experts in the field of haemophilia from across Europe to draft resolutions regarding current issues relating to the treatment of haemophilia. Hospitals providing clinical care for people with haemophilia and related disorders are strongly recommended to seek formal designation as either European Haemophilia Treatment Centres (EHTC) or European Haemophilia Comprehensive Care Centres (EHCCC). There should be agreed national protocols or guidelines on management of the ageing patient with haemophilia. The minimum consumption of factor VIII and IX concentrate in any country should be 4 IU and 0.5 IU per capita of general population respectively. Treatment for hepatitis C with direct-acting antiviral agents should be provided to all people with haemophilia on a priority basis. Genotype analysis should be offered to all patients with severe haemophilia. Genetic counselling, when given, should encompass the recommendation that genetic relatives of the affected person be advised to seek genetic counselling. People with inhibitors should have access to bypassing agents, immune tolerance and elective surgery. National or regional tenders for factor concentrates are encouraged. Outcome data including health related quality of life should be collected. Treatment with extended half-life factors should be individualized and protection against bleeding should be improved by increasing trough levels. Steps should be taken to understand and minimize the risk of inhibitor development. It is hoped that these recommendations will help to foster equity of haemophilia care throughout Europe. © 2017 John Wiley & Sons Ltd.

Stability of hemostatic proteins in canine fresh-frozen plasma thawed with a modified commercial microwave warmer or warm water bath.

PubMed

Pashmakova, Medora B; Barr, James W; Bishop, Micah A

2015-05-01

To compare stability of hemostatic proteins in canine fresh-frozen plasma (FFP) thawed with a modified commercial microwave warmer (MCM) or warm water bath (37°C; WWB) or at room temperature (22°C). Fresh-frozen plasma obtained from 8 canine donors of a commercial blood bank. A commercial microwave warmer was modified with a thermocouple to measure surface temperature of bags containing plasma. The MCM and a WWB were each used to concurrently thaw a 60-mL bag of plasma obtained from the same donor. Two 3-mL control aliquots of FFP from each donor were thawed to room temperature without use of a heating device. Concentrations of hemostatic proteins, albumin, and D-dimers; prothrombin time (PT); and activated partial thromboplastin time (aPTT) were determined for all samples. Significant decreases in concentrations of factors II, IX, X, XI, fibrinogen, von Willebrand factor, antithrombin, protein C, and albumin and significant increases in PT and aPTT were detected for plasma thawed with the MCM, compared with results for samples thawed with the WWB. Concentrations of factors VII, VIII, and XII were not significantly different between plasma thawed with the MCM and WWB. Concentrations of D-dimers were above the reference range for all thawed samples regardless of thawing method. No significant differences in factor concentrations were detected between control and WWB-thawed samples. Significant differences in hemostatic protein concentrations and coagulation times were detected for plasma thawed with an MCM but not between control and WWB-thawed samples. Clinical importance of these changes should be investigated.

Low-dose factor VIII infusion in Chinese adult haemophilia A patients: pharmacokinetics evidence that daily infusion results in higher trough level than with every-other-day infusion with similar factor VIII consumption.

PubMed

Hua, B; Lee, A; Fan, L; Li, K; Zhang, Y; Poon, M-C; Zhao, Y

2017-05-01

Pharmacokinetics (PK) modelling suggests improvement of trough levels are achieved by using more frequent infusion strategy. However, no clinical study data exists to confirm or quantify improvement in trough level, particularly for low-dose prophylaxis in patients with haemophilia A. To provide evidence that low dose daily (ED) prophylaxis can increase trough levels without increasing FVIII consumption compared to every-other-day (EOD) infusion. A cross-over study on 5 IU kg -1 FVIII daily vs. 10 IU kg -1 EOD infusions, each for 14 days was conducted at the PUMCH-HTC. On the ED schedule, trough (immediate prior to infusion), and peak FVIII:C levels (30 min after infusion) were measured on days 1-5; and trough levels alone on days 7, 9, 11 and 13. For the EOD schedule, troughs, peaks and 4-h postinfusion were measured on day 1; troughs and peaks on days 3, 5, and 7; troughs alone on days 9, 11 and 13 and 24-h postinfusion on days 2, 4 and 6. FVIII inhibitors were assessed on days 0 and 14 during both infusion schedules. Six patients were enrolled. PK evidence showed that daily prophylaxis achieved higher (~2 times) steady-state FVIII trough levels compared to EOD with the same total factor consumption. The daily prophylaxis had good acceptability among patients and reduced chronic pain in the joints in some patients. Our PK study shows low-dose factor VIII daily infusion results in higher trough level than with EOD infusion with similar factor VIII consumption in Chinese adult haemophilia A patients. © 2017 John Wiley & Sons Ltd.

An exploratory factor analysis of inflammatory and coagulation markers associated with femoral artery atherosclerosis in the San Diego Population Study.

PubMed

Egnot, Natalie Suder; Barinas-Mitchell, Emma; Criqui, Michael H; Allison, Matthew A; Ix, Joachim H; Jenny, Nancy S; Wassel, Christina L

2018-04-01

Several biomarkers of inflammation and coagulation have been implicated in lower extremity atherosclerosis. We utilized an exploratory factor analysis (EFA) to identify distinct factors derived from circulating inflammatory and coagulation biomarkers then examined the associations of these factors with measures of lower extremity subclinical atherosclerosis, including the ankle-brachial index (ABI), common and superficial femoral intima-media thickness (IMT), and atherosclerotic plaque presence, burden, and characteristics. The San Diego Population Study (SDPS) is a prospective, community-living, multi-ethnic cohort of 1103 men and women averaged age 70. Regression analysis was used to assess cross-sectional associations between the identified groupings of biomarkers (factors) and the ABI and femoral artery atherosclerosis measurements. Two biomarker factors emerged from the factor analysis. Factor 1 consisting of C-reactive protein (CRP), interleukin (IL)-6, and fibrinogen was significantly associated with higher odds (OR = 1.99, p < 0.01) of a borderline ABI value (0.91-0.99), while Factor 2 containing D-dimer and pentraxin (PTX)-3 was significantly associated with higher common femoral artery (CFA) IMT (β = 0.23, p < 0.01) and lower ABI (β = -0.03, p < 0.01). Two groupings of biomarkers were identified via EFA of seven circulating biomarkers of inflammation and coagulation. These distinct groups are differentially associated with markers of lower extremity subclinical atherosclerosis. Our findings suggest that high inflammatory and coagulation burden were better markers of more severe lower-extremity disease as indicated by low ABI rather than early atherosclerotic lesion development in the femoral artery. Copyright © 2018 Elsevier Ltd. All rights reserved.

Complement Activation Alters Platelet Function

DTIC Science & Technology

2015-12-01

haemostatic and coagulation properties of platelets. 15. SUBJECT TERMS Platelets, Complement, Trauma, Tissue Damage 16. SECURITY CLASSIFICATION... coagulation , there is mounting evidence that they may also be important in the development and progression of inflammatory processes (Coppinger et al...receptor-ligand interactions and/or through exposure to cytokines including IL-6, other acute-phase reactants, and pro- coagulant factors such as thrombin

Multiple response optimization of the coagulation process for upgrading the quality of effluent from municipal wastewater treatment plant

NASA Astrophysics Data System (ADS)

Li, Na; Hu, Yi; Lu, Yong-Ze; Zeng, Raymond J.; Sheng, Guo-Ping

2016-05-01

To meet the high quality standard of receiving water, the coagulation process using polyferric chloride (PFC) was used to further improve the water quality of effluent from wastewater treatment plants. Uniform design (UD) coupled with response surface methodology (RSM) was adopted to assess the effects of the main influence factors: coagulant dosage, pH and basicity, on the removal of total organic carbon (TOC), NH4+-N and PO43--P. A desirability function approach was used to effectively optimize the coagulation process for the comprehensive removal of TOC, NH4+-N and PO43--P to upgrade the effluent quality in practical application. The optimized operating conditions were: dosage 28 mg/L, pH 8.5 and basicity 0.001. The corresponding removal efficiencies for TOC, NH4+-N and PO43--P were 77.2%, 94.6% and 20.8%, respectively. More importantly, the effluent quality could upgrade to surface water Class V of China through coagulation under optimal region. In addition, grey relational analysis (GRA) prioritized these three factors as: pH > basicity > dosage (for TOC), basicity > dosage > pH (for NH4+-N), pH > dosage > basicity (for PO43--P), which would help identify the most important factor to control the treatment efficiency of various effluent quality indexes by PFC coagulation.

Thymoquinone Modulates Blood Coagulation in Vitro via Its Effects on Inflammatory and Coagulation Pathways

PubMed Central

Muralidharan-Chari, Vandhana; Kim, Jaehan; Abuawad, Ahlam; Naeem, Mubeena; Cui, Huadong; Mousa, Shaker A.

2016-01-01

Thymoquinone (THQ) is a major component of black seeds. Given that both THQ and black seeds exhibit anti-cancer and anti-inflammatory activities, we hypothesized that THQ will affect cancer-associated thrombosis (CAT), which is primarily triggered by tissue factor (TF) and inflammation. The effect of both black seed-extracted and purchased (“pure”) THQ on normal blood coagulation was tested with in vitro thromboelastography (TEG) and activated partial thromboplastin time (aPTT) coagulation assays. The effect of pure THQ on CAT was tested with aPTT assay using pancreatic cancer cell lines that are either positive or negative for TF, and with TEG assay using lipopolysaccharide as an inflammatory trigger. Additionally, the direct effect of THQ on the inactivation of factors IIa and Xa was assessed. Since TNF-α facilitates crosstalk between inflammation and thrombosis by triggering the NF-κB pathway, we tested THQ’s ability to interfere with this communication with a luciferase assay. Both extracted and pure THQ had minimal effects on normal blood coagulation. Pure THQ reversed CAT initiated by both TF and inflammation to basal levels (p < 0.001). Mechanistically, while THQ had minimal to no effect on factor IIa and Xa inactivation, it strongly reduced the effects of TNF-α on NF-κB elements (p < 0.001). THQ has a minimal effect on basal coagulation and can reverse CAT in vitro, possibly by interfering with the crosstalk between inflammation and coagulation. This study suggests the utility of THQ as a preventative anticoagulant and/or as a supplement to existing chemotherapies and anticoagulant therapies. PMID:27043539

Appeals court reverses verdict favoring drug companies.

PubMed

1995-06-02

An appeals court reversed a verdict favoring drug companies after the widow of a hemophiliac, whose death was linked to HIV-tainted blood products, sued four pharmaceutical companies to pay damages. The four companies, Alpha Therapeutic Corp., Miles Laboratories Inc., Armour Pharmaceutical Co., and Baxter Travenol Laboratories Inc., provided Factor VIII, a clotting concentrate, to [name removed] [name removed], the plaintiff's husband, from 1972 until his death in 1987. [Name removed]'s wife sued the companies, alleging that the defendants negligently solicited blood plasma from paid donors who had a high risk of having HIV, failed to determine whether any lots of Factor VIII contained plasma from an at-risk donor, failed to warn consumers of possible risks, and failed to heat-treat HIV and other viruses in Factor VIII, despite industry-wide knowledge of the risk of infection. The three-judge panel said the trial judge's decision to avoid ruling on the antigenic stimulation theory, based on insufficient evidence, was improper. In addition, the appeals court said a retrial is necessary because of improper remarks made by Alpha's attorney.

Synthesis of Phosphatidylserine and Its Stereoisomers: Their Role in Activation of Blood Coagulation.

PubMed

Mallik, Suman; Prasad, Ramesh; Bhattacharya, Anindita; Sen, Prosenjit

2018-05-10

Natural phosphatidylserine (PS), which contains two chiral centers, enhances blood coagulation. However, the process by which PS enhanced blood coagulation is not completely understood. An efficient and flexible synthetic route has been developed to synthesize all of the possible stereoisomers of PS. In this study, we examined the role of PS chiral centers in modulating the activity of the tissue factor (TF)-factor VIIa coagulation initiation complex. Full length TF was relipidated with phosphatidylcholine, and the synthesized PS isomers were individually used to estimate the procoagulant activity of the TF-FVIIa complex via a FXa generation assay. The results revealed that the initiation complex activity was stereoselective and had increased sensitivity to the configuration of the PS glycerol backbone due to optimal protein-lipid interactions.

Blood coagulation factor XII drives adaptive immunity during neuroinflammation via CD87-mediated modulation of dendritic cells

PubMed Central

Göbel, Kerstin; Pankratz, Susann; Asaridou, Chloi-Magdalini; Herrmann, Alexander M.; Bittner, Stefan; Merker, Monika; Ruck, Tobias; Glumm, Sarah; Langhauser, Friederike; Kraft, Peter; Krug, Thorsten F.; Breuer, Johanna; Herold, Martin; Gross, Catharina C.; Beckmann, Denise; Korb-Pap, Adelheid; Schuhmann, Michael K.; Kuerten, Stefanie; Mitroulis, Ioannis; Ruppert, Clemens; Nolte, Marc W.; Panousis, Con; Klotz, Luisa; Kehrel, Beate; Korn, Thomas; Langer, Harald F.; Pap, Thomas; Nieswandt, Bernhard; Wiendl, Heinz; Chavakis, Triantafyllos; Kleinschnitz, Christoph; Meuth, Sven G.

2016-01-01

Aberrant immune responses represent the underlying cause of central nervous system (CNS) autoimmunity, including multiple sclerosis (MS). Recent evidence implicated the crosstalk between coagulation and immunity in CNS autoimmunity. Here we identify coagulation factor XII (FXII), the initiator of the intrinsic coagulation cascade and the kallikrein–kinin system, as a specific immune cell modulator. High levels of FXII activity are present in the plasma of MS patients during relapse. Deficiency or pharmacologic blockade of FXII renders mice less susceptible to experimental autoimmune encephalomyelitis (a model of MS) and is accompanied by reduced numbers of interleukin-17A-producing T cells. Immune activation by FXII is mediated by dendritic cells in a CD87-dependent manner and involves alterations in intracellular cyclic AMP formation. Our study demonstrates that a member of the plasmatic coagulation cascade is a key mediator of autoimmunity. FXII inhibition may provide a strategy to combat MS and other immune-related disorders. PMID:27188843

Relationships of inflammatory and haemostatic markers with social class: results from a population-based study of older men.

PubMed

Ramsay, Sheena; Lowe, Gordon D O; Whincup, Peter H; Rumley, Ann; Morris, Richard W; Wannamethee, S Goya

2008-04-01

Haemostatic and inflammatory markers have been hypothesised to mediate the relationship of social class and cardiovascular disease (CVD). We investigated whether a range of inflammatory/haemostatic markers are associated with social class independent of chronic diseases and behavioural risk factors in a population-based sample of 2682 British men aged 60-79 without a physician diagnosis of CVD, diabetes or musculoskeletal disease requiring anti-inflammatory medications. Men in lower social classes had higher mean levels of C-reactive protein, fibrinogen, interleukin-6, white blood cell count, von Willebrand factor (vWF), factor VIII, activated protein C (APC) resistance, plasma viscosity, fibrin D-dimer and platelet count, compared to higher social class groups; but not of tissue plasminogen activator antigen, haematocrit or activated partial prothrombin time. After adjustment for behavioural risk factors (smoking, alcohol, physical activity and body mass), the associations of social class with vWF, factor VIII, APC resistance, plasma viscosity, and platelet count though weakened, remained statistically significant, while those of other markers were considerably attenuated. In this study of older men without CVD, the social gradient in inflammatory and haemostatic markers was substantially explained by behavioural risk factors. The effect of socio-economic gradient on the factor VIII-vWF complex, APC resistance, plasma viscosity and platelet count merits further study.

Application of Cox model in coagulation function in patients with primary liver cancer.

PubMed

Guo, Xuan; Chen, Mingwei; Ding, Li; Zhao, Shan; Wang, Yuefei; Kang, Qinjiong; Liu, Yi

2011-01-01

To analyze the distribution of coagulation parameters in patients with primary liver cancer; explore the relationship between clinical staging, survival, and coagulation parameters by using Coxproportional hazard model; and provide a parameter for clinical management and prognosis. Coagulation parameters were evaluated in 228 patients with primary liver cancer, 52 patients with common liver disease, and 52 normal healthy controls. The relationship between primary livercancer staging and coagulation parameters wasanalyzed. Follow-up examinations were performed. The Cox proportional hazard model was used to analyze the relationship between coagulationparameters and survival. The changes in the coagulation parameters in patients with primary liver cancer were significantly different from those in normal controls. The effect of the disease on coagulation function became more obvious as the severity of liver cancer increased (p<0.05). The levels of D-dimer, fibrinogen degradation products (FDP), fibrinogen (FIB), and platelets (PLT) were negatively correlated with the long-term survival of patients with advanced liver cancer. The stages of primary liver cancer are associated with coagulation parameters. Coagulation parameters are related to survival and risk factors. Monitoring of coagulation parameters may help ensure better surveillance and treatment for liver cancer patients.

Testing of Intravenous Hemostatic Agents in a Novel Swine Model of Bleeding: Preliminary Results With FXa-PCPs

DTIC Science & Technology

2005-08-01

proceeds through a prothrombinase complex (prothrombin, factor Va, calcium, and phospholipid). Thrombin is the final product in the coagulation cascade...we report preliminary data on the efficacy of mixtures of highly purified blood coagulation factors (FVIIa and FXa) and phospholipids vesicles (PCPS...testing. Further study of these drugs for the use of traumatic hemorrhage is not warranted. 15. SUBJECT TERMS Recombinant Factor VI~a, factor Xa

The Potential Role of Recombinant Activated Factor VIIa (rFVIIa) in Military Pre-Hospital Setting

DTIC Science & Technology

2004-09-01

coagulation factors and platelets by crystalloids, colloids, or blood products The severity of dilutional coagulopathy is determined by both volume and...RTO-MP-HFM-109 3 - 1 The Potential Role of Recombinant Activated Factor VIIa (rFVIIa) in Military Pre-Hospital Setting LTC (ret.) Uri...decrease mortality from exsanguinations. Recombinant factor VIIa (rFVIIa) has been shown to overcome a variety of coagulation and platelet disorders

von Willebrand factor and factor VIII are independently required to form stable occlusive thrombi in injured veins

PubMed Central

Chauhan, Anil K.; Kisucka, Janka; Lamb, Colin B.; Bergmeier, Wolfgang

2007-01-01

von Willebrand factor (VWF) protects factor VIII (FVIII) from proteolysis and mediates the initial contact of platelets with the injured vessel wall, thus playing an important role in hemostasis and thrombosis. VWF is crucial for the formation of occlusive thrombi at arterial shear rates. However, with only a few conflicting studies published, the role of VWF in venous thrombosis is still unclear. Using gene-targeted mice, we show that in ferric chloride–injured veins platelet adhesion to subendothelium is decreased and thrombus growth is impaired in VWF−/− mice when compared with wild type (WT). We also observed increased embolization in the VWF−/− mice, which was due to lower FVIII levels in these mice as recombinant factor VIII (r-FVIII) restored thrombus stability. Despite normalization of blood clotting time and thrombus stability after r-FVIII infusion, the VWF−/− venules did not occlude. Transgenic platelets lacking the VWF receptor GPIbα extracellular domain showed decreased adhesion to injured veins. But, after a delay, all the injured venules occluded in these transgenic mice. Thus, VWF likely uses other adhesion receptors besides GPIbα in thrombus growth under venous shear conditions. Our studies document crucial roles for VWF and FVIII in experimental thrombosis under venous flow conditions in vivo. PMID:17119108

[Hereditary heterozygous factor VII deficiency in patients undergoing surgery : Clinical relevance].

PubMed

Woehrle, D; Martinez, M; Bolliger, D

2016-10-01

A hereditary deficiency in coagulation factor VII (FVII) may affect the international normalized ratio (INR) value. However, FVII deficiency is occasionally associated with a tendency to bleed spontaneously. We hypothesized that perioperative substitution with coagulation factor concentrates might not be indicated in most patients. In this retrospective data analysis, we included all patients with hereditary heterozygous FVII deficiency who underwent surgical procedures at the University Hospital Basel between December 2010 and November 2015. In addition, by searching the literature, we identified publications reporting patients with FVII deficiency undergoing surgical procedures without perioperative substitution. We identified 22 patients undergoing 46 surgical procedures, resulting in a prevalence of 1:1500-2000. Coagulation factor concentrates were administered during the perioperative period in 15 procedures (33 %), whereas in the other 31 procedures (66 %), FVII deficiency was not substituted. No postoperative bleeding or thromboembolic events were reported. In addition, we found no differences in pre- and postoperative hemoglobin and coagulation parameters, with the exception of an improved postoperative INR value in the substituted group. In the literature review, we identified five publications, including 125 patients with FVII deficiency, undergoing 213 surgical procedures with no perioperative substitution. Preoperative substitution using coagulation factor concentrates does not seem to be mandatory in patients with an FVII level ≥15 %. For decision-making on preoperative substitution, patient history of an increased tendency to bleed may be more important than the FVII level or increased INR value.

Chromosome VIII disomy influences the nonsense suppression efficiency and transition metal tolerance of the yeast Saccharomyces cerevisiae.

PubMed

Zadorsky, S P; Sopova, Y V; Andreichuk, D Y; Startsev, V A; Medvedeva, V P; Inge-Vechtomov, S G

2015-06-01

The SUP35 gene of the yeast Saccharomyces cerevisiae encodes the translation termination factor eRF3. Mutations in this gene lead to the suppression of nonsense mutations and a number of other pleiotropic phenotypes, one of which is impaired chromosome segregation during cell division. Similar effects result from replacing the S. cerevisiae SUP35 gene with its orthologues. A number of genetic and epigenetic changes that occur in the sup35 background result in partial compensation for this suppressor effect. In this study we showed that in S. cerevisiae strains in which the SUP35 orthologue from the yeast Pichia methanolica replaces the S. cerevisiae SUP35 gene, chromosome VIII disomy results in decreased efficiency of nonsense suppression. This antisuppressor effect is not associated with decreased stop codon read-through. We identified SBP1, a gene that localizes to chromosome VIII, as a dosage-dependent antisuppressor that strongly contributes to the overall antisuppressor effect of chromosome VIII disomy. Disomy of chromosome VIII also leads to a change in the yeast strains' tolerance of a number of transition metal salts. Copyright © 2015 John Wiley & Sons, Ltd.

Self-production of tissue factor-coagulation factor VII complex by ovarian cancer cells.

PubMed

Yokota, N; Koizume, S; Miyagi, E; Hirahara, F; Nakamura, Y; Kikuchi, K; Ruf, W; Sakuma, Y; Tsuchiya, E; Miyagi, Y

2009-12-15

Thromboembolic events are a major complication in ovarian cancer patients. Tissue factor (TF) is frequently overexpressed in ovarian cancer tissue and correlates with intravascular thrombosis. TF binds to coagulation factor VII (fVII), changing it to its active form, fVIIa. This leads to activation of the extrinsic coagulation cascade. fVII is produced by the liver and believed to be supplied from blood plasma at the site of coagulation. However, we recently showed that ovarian cancer cells express fVII transcripts under normoxia and that this transcription is inducible under hypoxia. These findings led us to hypothesise that ovarian cancer cells are intrinsically associated with TF-fVIIa coagulation activity, which could result in thrombosis. In this study, we examined whether ectopically expressed fVII could cause thrombosis by means of immunohistochemistry, RT-PCR, western blotting and flow cytometry. Ectopic fVII expression occurs frequently in ovarian cancers, particularly in clear cell carcinoma. We further showed that ovarian cancer cells express TF-fVIIa on the cell surface under normoxia and that this procoagulant activity is enhanced by hypoxic stimuli. Moreover, we showed that ovarian cancer cells secrete microparticles (MPs) with TF-fVIIa activity. Production of this procoagulant secretion is enhanced under hypoxia. These results raise the possibility that cancer cell-derived TF-fVIIa could cause thrombotic events in ovarian cancer patients.

Proposal of the Coagulation Score as a Predictor for Short-Term and Long-Term Outcomes of Patients with Resectable Gastric Cancer.

PubMed

Kanda, Mitsuro; Tanaka, Chie; Kobayashi, Daisuke; Mizuno, Akira; Tanaka, Yuri; Takami, Hideki; Iwata, Naoki; Hayashi, Masamichi; Niwa, Yukiko; Yamada, Suguru; Fujii, Tsutomu; Sugimoto, Hiroyuki; Murotani, Kenta; Fujiwara, Michitaka; Kodera, Yasuhiro

2017-02-01

Systemic hemostasis and thrombosis activation has been implicated in tumor progression and metastasis. This study aimed to investigate the use of coagulation factors as a novel prediction method for postoperative outcomes after curative gastrectomy in patients with stage II/III gastric cancer (GC). Overall, 126 patients with stage II/III GC who underwent gastrectomy between May 2003 and February 2016 were eligible for inclusion in the study. We retrospectively evaluated the predictive value of preoperative platelet count and plasma fibrinogen and d-dimer levels, and coagulation score (0: fibrinogen and d-dimer both below upper limits; 1: either fibrinogen or d-dimer over upper limits; 2: both fibrinogen and d-dimer over upper limits) for short- and long-term outcomes. Postoperative complications were significantly more frequent in patients with elevated preoperative d-dimer levels compared with those with normal d-dimer levels (26 vs. 10 %; p = 0.032). The prevalence of postoperative complications showed a stepwise increase in proportion to the coagulation score. Patients with a coagulation score of 2 had significantly larger tumors (p = 0.013) and significantly greater intraoperative blood loss (p = 0.004) than those who scored 0 or 1. Coagulation score showed the highest values distinguished high-risk patients in overall and disease-free survival, and a coagulation score of 2 was an independent prognostic factor for recurrence. Patients with a coagulation score of 2 experienced a significantly higher prevalence of liver metastasis as an initial recurrence than those who scored 0 or 1 (p = 0.019). The coagulation score is a simple and promising predictor for postoperative complications and recurrence after gastrectomy in stage II/III GC patients.

Coagulation indices in very preterm infants from cord blood and postnatal samples.

PubMed

Neary, E; McCallion, N; Kevane, B; Cotter, M; Egan, K; Regan, I; Kirkham, C; Mooney, C; Coulter-Smith, S; Ní Áinle, F

2015-11-01

Very premature infants are at high risk of bleeding complications; however, few data exist on ranges for standard coagulation tests. The primary objective of this study was to measure standard plasma coagulation tests and thrombin generation in very premature infants compared with term infants. The secondary objective was to evaluate whether an association existed between coagulation indices and intraventricular hemorrhage (IVH). Cord and peripheral blood of neonates < 30 weeks gestational age (GA) was drawn at birth, on days 1 and 3 and fortnightly until 30 weeks corrected gestational age. Prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen and coagulation factor levels were measured and tissue factor-stimulated thrombin generation was characterized. Control plasma was obtained from cord blood of term neonates. One hundred and sixteen infants were recruited. Median (range) GA was 27.7 (23.7-29.9) weeks and mean (SD) birth weight was 1020 (255) g. Median (5th-95th percentile) day 1 PT, APTT and fibrinogen were 17.5 (12.7-26.6) s, 78.7 (48.7-134.3) s and 1.4 (0.72-3.8) g L(-1) , respectively. No difference in endogenous thrombin potential between preterm and term plasma was observed, where samples were available. Levels of coagulation factors II, VII, IX and X, protein C, protein S and antithrombin were reduced in preterm compared with term plasma. Day 1 APTT and PT were not associated with IVH. In the largest cross-sectional study to date of very preterm infants, typical ranges for standard coagulation tests were determined. Despite long clotting times, thrombin generation was observed to be similar in very preterm and term infants. © 2015 International Society on Thrombosis and Haemostasis.

Synergistic effect of a factor Xa inhibitor, TAK-442, and antiplatelet agents on whole blood coagulation and arterial thrombosis in rats.

PubMed

Konishi, Noriko; Hiroe, Katsuhiko; Kawamura, Masaki

2010-08-01

Activated platelets facilitate blood coagulation by providing factor V and a procoagulant surface for prothrombinase. Here, we investigated the potential synergy of a potent factor Xa/prothrombinase inhibitor, TAK-442, plus aspirin or clopidogrel in preventing arterial thrombosis and whole blood coagulation. Thrombus formation was initiated by FeCl(3)-induced rat carotid injury. Bleeding time was evaluated with the rat tail transection model. Whole blood coagulation was assessed by thromboelastographic examination (TEG) for which blood obtained from control, aspirin-, or clopidogrel-treated rats was transferred to a TEG analyzer containing, collagen or adenosine diphosphate (ADP), and TAK-442 or vehicle. TAK-442 (3mg/kg, po), aspirin (100mg/kg, po) or clopidogrel (3mg/kg, po) alone had no significant effect on thrombus formation, whereas the combination of TAK-442 with aspirin and clopidogrel remarkably prolonged the time to thrombus formation without additional significant prolongation of bleeding time. TEG demonstrated that the onset of collagen-induced blood coagulation were slightly longer in aspirin-treated rats than control; however, when the blood from aspirin-treated rats was subsequently treated in vitro with 100 nM TAK-442, the onset of clotting was significantly prolonged. In contrast, only marginal prolongation was observed with TAK-442 treatment of blood from control animals. The onset time of ADP-induced blood coagulation was slightly longer in clopidogrel-treated rats compared with control, and it was further extended by TAK-442 treatment. These results demonstrate that blood coagulation can be markedly delayed by the addition of TAK-442 to antiplatelets treatment which could contribute to synergistic antithrombotic efficacy in these settings. (c) 2010 Elsevier Ltd. All rights reserved.

Effect of chitosan and coagulation factors on the wound repair phenotype of bioengineered blood clots.

PubMed

Hoemann, Caroline D; Marchand, Catherine; Rivard, Georges-Etienne; El-Gabalawy, Hani; Poubelle, Patrice E

2017-11-01

Controlling the blood clot phenotype in a surgically prepared wound is an evolving concept in scaffold-guided tissue engineering. Here, we investigated the effect of added chitosan (80% or 95% Degree of Deacetylation, DDA) or coagulation factors (recombinant human Factor VIIa, Tissue Factor, thrombin) on inflammatory factors released by blood clots. We tested the hypothesis that 80% DDA chitosan specifically enhances leukotriene B 4 (LTB 4 ) production. Human or rabbit whole blood was combined with isotonic chitosan solutions, coagulation factors, or lipopolysaccharide, cultured in vitro at 37°C, and after 4hours the serum was assayed for LTB 4 or inflammatory factors. Only 80% DDA chitosan clots produced around 15-fold more LTB 4 over other clots including 95% DDA chitosan clots. All serum contained high levels of PDGF-BB and CXCL8. Normal clots produced very low type I cytokines compared to lipopolysaccharide clots, with even lower IL-6 and IL-12 and more CCL3/CCL4 produced by chitosan clots. Coagulation factors had no detectable effect on clot phenotype. Conclusion In blood clots from healthy individuals, 80% DDA chitosan has a unique influence of inducing more LTB 4 , a potent neutrophil chemoattractant, with similar production of PDGF-BB and CXCL8, and lower type I cytokines, compared to whole blood clots. Copyright © 2017 Elsevier B.V. All rights reserved.

Prevalence of IgG antibodies to human parvovirus B19 in haemophilia children treated with recombinant factor (F)VIII only or with at least one plasma-derived FVIII or FIX concentrate: results from the French haemophilia cohort.

PubMed

Gaboulaud, Valérie; Parquet, Armelle; Tahiri, Cedric; Claeyssens, Ségolène; Potard, Valérie; Faradji, Albert; Peynet, Jocelyne; Costagliola, Dominique

2002-02-01

Human parvovirus B19 (B19) has been transmitted by some brands of virally attenuated plasma-derived factor VIII (FVIII) or IX (FIX) concentrates. To quantify the differences of human parvovirus B19 risk transmission between albumin-stabilized recombinant factor and plasma-derived factor, we studied the prevalence of IgG antibodies to B19 (anti-B19) in 193 haemophiliac children between 1 and 6-years of age who had previously been treated with albumin-stabilized recombinant FVIII only (n = 104), and in children previously treated with solvent/detergent high-purity non-immunopurified and non-nanofiltered FVIII or IX concentrates (n = 89). Association between the prevalence of anti-B19 and the treatment group was analysed using multivariate logistic regression. Age, severity and type of haemophilia, number of cumulative days of exposure to factor VIII or IX, previous history of red blood cells or plasma transfusion were considered as potential confounding variables. A higher prevalence of anti-B19 was found in children previously treated with solvent/detergent high-purity non-immunopurified and non-nanofiltered FVIII or IX concentrates than in children treated with albumin- stabilized recombinant FVIII only (OR: 22.3; CI: 7.9-62.8), independently of the other factors studied.

The effect of corn trypsin inhibitor and inhibiting antibodies for FXIa and FXIIa on coagulation of plasma and whole blood.

PubMed

Hansson, K M; Nielsen, S; Elg, M; Deinum, J

2014-10-01

Corn trypsin inhibitor (CTI), an inhibitor of FXIIa, is used to prevent plasma coagulation by contact activation, to specifically investigate tissue factor (TF)-initiated coagulation. In the present work the specificity of CTI for factor (F) XIIa is questioned. In the commercial available plasma coagulation assays CTI was found to double activated partial thromboplastin time (APTT) at a plasma concentration of 7.3 ± 1.5 μm CTI (assay concentration 2.4 μm). No effect was found on the prothrombin time (PT) when high TF concentrations were used. Also, with specific antibodies for FXIIa and for FXIa only APTT was found to be extended but not PT. With specific enzyme assays using chromogenic substrates CTI was shown to be a strong inhibitor of FXIIa and a competitive inhibitor of FXIa with Ki  = 8.1 ± 0.3 μm, without effect on the coagulation factors FVIIa, FIXa, FXa and thrombin. In thrombin generation and coagulation (free oscillation rheometry, FOR) assays, initiated with low TF concentrations, no effect of CTI (plasma concentrations of 4.4 and 13.6 μm CTI, 25 resp. 100 mg L(-1) in blood) was found with ≥ 1 pm TF. At ≤ 0.1 pm TF in the FOR whole blood assay the coagulation time (CT) concentration dependently increased while the plasma CT became longer than the observation time. To avoid inhibition of FXIa and the thrombin feedback loop we recommend that for coagulation assays the concentration of CTI in blood should be below 20 mg L(-1) (1.6 μm) and in plasma below 3 μm. © 2014 International Society on Thrombosis and Haemostasis.

Mutation in the factor VII hepatocyte nuclear factor 4α-binding site contributes to factor VII deficiency.

PubMed

Zheng, Xing-Wu; Kudaravalli, Rama; Russell, Theresa T; DiMichele, Donna M; Gibb, Constance; Russell, J Eric; Margaritis, Paris; Pollak, Eleanor S

2011-10-01

Severe coagulant factor VII (FVII) deficiency in postpubertal dizygotic twin males results from two point mutations in the FVII gene, a promoter region T→C transition at -60 and a His-to-Arg substitution at amino acid 348; both mutations prevent persistence of plasma functional FVII. This report documents longitudinal laboratory measurements from infancy to adulthood of FVII coagulant activity (FVII:C) in the twin FVII-deficient patients; it also details specific biochemical analyses of the -60 T→C mutation. The results revealed FVII:C levels of less than 1% in infancy that remain severely decreased through puberty and into adulthood. In-vitro analyses utilizing hepatocyte nuclear factor 4α (HNF4α) co-transfection and a chromatin immunoprecipitation assay indicate that the -60 T→C mutation severely diminishes functional interaction between the FVII promoter and transcription factor HNF4α. The importance of interaction between the FVII gene and HNF4α in normal FVII expression provides an in-vivo illustration of the regulated expression of an autosomal gene encoding a coagulation protein. The constancy of FVII:C and peripubertal patient symptomatology reported here illustrates androgen-independent expression in contrast to expression with an analogous mutation in the promoter region of the gene encoding coagulation FIX.

Plasmodium falciparum-infected erythrocytes induce Tissue Factor expression in endothelial cells and support the assembly of multimolecular coagulation complexes

PubMed Central

Francischetti, Ivo MB; Seydel, Karl B; Monteiro, Robson Q; Whitten, Richard O; Erexson, Cindy R; Noronha, Almério LL; Ostera, Graciela R.; Kamiza, Steve B; Molyneux, Malcolm E; Ward, Jerrold M; Taylor, Terrie E

2010-01-01

Summary Background Plasmodium falciparum malaria infects 300–500 million people every year causing 1–2 million deaths annually. Evidence of a coagulation disorder, activation of endothelial cells (EC) and increase in inflammatory cytokines are often present in malaria. Objectives We have asked whether parasitized red blood cells (pRBC) interaction with EC induces Tissue Factor expression in vitro and in vivo. The potential of phosphatidylserine-containing pRBC to support the assembly of blood coagulation complexes was also investigated. Results We demonstrate that mature forms of pRBC induce functional expression of tissue factor (TF) by endothelial cells (EC) in vitro with productive assembly of the extrinsic Xnase complex and initiation of the coagulation cascade. Late stage pRBC also support the prothrombinase and intrinsic Xnase complex formation in vitro, and may function as activated platelets in the amplification phase of the blood coagulation. Notably, postmortem brain sections obtained from P. falciparum-infected children who died from Cerebral Malaria and other causes display a consistent staining for TF in the EC. Conclusions These findings place TF expression by endothelium and the amplification of the coagulation cascade by pRBC and/or activated platelets as potentially critical steps in the pathogenesis of malaria. Furthermore, it may allow investigators to test other therapeutic alternatives targeting TF or modulators of EC function in the treatment of malaria and/or its complications. PMID:17002660

Hemophilia and von Willebrand's disease: 1. Diagnosis, comprehensive care and assessment. Association of Hemophilia Clinic Directors of Canada.

PubMed Central

1995-01-01

OBJECTIVE: To present current strategies for the assessment and comprehensive care of patients with hemophilia and von Willebrand's disease. OPTIONS: Hospital care, home care, single-provider care and multidisciplinary care. OUTCOMES: Morbidity and quality of life associated with bleeding and treatment. EVIDENCE: Relevant clinical studies and reports published from 1974 to 1994 were examined. A search was conducted of own reprint files, MEDLINE, citations in the articles reviewed and references provided by colleagues. In the MEDLINE search the following terms were used singly or in combination: "hemophilia," "von Willebrand's disease," "Factor VIII," "Factor IX," "von Willebrand factor," "diagnosis," "management," "home care," "comprehensive care," "inhibitor," "AIDS," "hepatitis," "life expectancy," "complications," "practice guidelines," "consensus statement" and "controlled trial." The in-depth review included only articles written in English from North America and Europe that were relevant to human disease and to a predetermined outline. The availability of treatment products in Canada was also considered. VALUES: Minimizing morbidity and maximizing functional status and quality of life were given a high value. BENEFITS, HARMS AND COSTS: The optimal use of treatment procedures and home care offers patients the advantages of minimized disability, improved survival and financial benefit. It is also cost effective. Potential harm, including the risk of hepatitis B, hepatitis C and HIV infection, has now been minimized through viral inactivation of plasma-derived coagulation-factor concentrates and through the use of recombinant clotting factor concentrates and other non-plasma-derived hemostatic agents. RECOMMENDATIONS: Patients with hemophilia and severe von Willebrand's disease should be followed in comprehensive care centres that offer expertise in the diagnosis, assessment and management of bleeding and complications and that can meet the educational and counselling needs of patients, family members and health care providers. Eligible patients should be enrolled in a home self-infusion program. Patients with hemophilia and von Willebrand's disease should wear or carry Medic Alert identification. They should be vaccinated against hepatitis B and attend for routine follow-up examinations. Laboratory testing should be carried out as required, and dental and surgical care should be undertaken in consultation with a hematologist. VALIDATION: These recommendations were reviewed and approved by the Association of Hemophilia Clinic Directors of Canada (AHCDC) and the Medical and Scientific Advisory Committee of the Canadian Hemophilia Society. No similar consensus statements or practice guidelines are available for comparison. SPONSORS: These recommendations were developed at the request of the Canadian Blood Agency, which funds the provision of all coagulation-factor concentrates for people with congenital bleeding disorders, and were developed and endorsed by the AHCDC and the Medical and Scientific Advisory Committee of the Canadian Hemophilia Society. PMID:7796372

Geochemical controls on vanadium accumulation in fossil fuels

USGS Publications Warehouse

Breit, G.N.; Wanty, R.B.

1989-01-01

High vanadium contents in petroleum and other fossil fuels have been attributed to organic-matter type, organisms, volcanic emanations, diffusion of sea water, and epigenetic enrichment. However, these factors are inadequate to account for the high abundance of vanadium in some fossil fuels and the paucity in others. By examining vanadium deposits in sedimentary rocks with sparse organic matter, constraints are placed on processes controlling vanadium accumulation in organic-rich sediments. Vanadium, as vanadate (V(V)), entered some depositional basins in oxidizing waters from dry, subaerial environments. Upon contact with organic matter in anoxic waters, V(V) is reduced to vanadyl (V(IV)), which can be removed from the water column by adsorption. H2S reduces V(IV) to V(III), which hydrolyzes and precipitates. The lack of V(III) in petroleum suggests that reduction of V(IV) to V(III) is inhibited by organic complexes. In the absence of strong complexing agents, V(III) forms and is incorporated in clay minerals.

Geochemical controls of vanadium accumulation in fossil fuels

USGS Publications Warehouse

Breit, G.N.; Wanty, R.B.

1989-01-01

High vanadium contents in petroleum and other fossil fuels have been attributed to organic-matter type, organisms, volcanic emanations, diffusion of sea water, and epigenetic enrichment. However, these factors are inadequate to account for the high abundance of vanadium in some fossil fuels and the paucity in others. By examining vanadium deposits in sedimentary rocks with sparse organic matter, constraints are placed on processes controlling vanadium accumulation in organic-rich sediments. Vanadium, as vanadate (V(V)), entered some depositional basins in oxidizing waters from dry, subaerial environments. Upon contact with organic matter in anoxic waters, V(V) is reduced to vanadyl (V(IV)), which can be removed from the water column by adsorption. H2S reduces V(IV) to V(III), which hydrolyzes and precipitates. The lack of V(III) in petroleum suggests that reduction of V(IV) to V(III) is inhibited by organic complexes. In the absence of strong complexing agents, V(III) forms and is incorporated in clay minerals.

No effect of isolated long-term supine immobilization or profound prolonged hypoxia on blood coagulation.

PubMed

Venemans-Jellema, A; Schreijer, A J M; Le Cessie, S; Emmerich, J; Rosendaal, F R; Cannegieter, S C

2014-06-01

Long-distance air travel is associated with an increased risk of venous thrombosis. The most obvious factor that can explain air travel-related thrombosis is prolonged seated immobilization. In addition, hypobaric hypoxia has been shown to affect coagulation, and the lowered atmospheric pressures present in the cabin during the flight may therefore play an etiologic role. Because immobilization and hypoxic conditions are usually present simultaneously in airplanes or hypobaric chambers, their separate effects on the coagulation system or on thrombosis risk have not been studied extensively. To investigate the separate effects of long-term immobilization and profound prolonged hypoxia on blood coagulation. We performed two studies in collaboration with European Space Agency/European Space Research and Technology Centre. In the first study, 24 healthy, non-smoking, adult women underwent 60 days of -6° head-down bed rest. In the second study, we took blood samples from 25 healthy men who participated during their stay in the Concordia station in Antarctica, where, due to the atmospheric conditions, continuous severe hypobaric hypoxia is present. In both studies, we measured markers of blood coagulation at baseline and at several time points during the exposures. We observed no increase in coagulation markers during immobilization or in the hypobaric environment, compared with baseline measurements. Our results indicate that neither immobilization nor hypoxia per se affects blood coagulation. These results implicate that a combination of risk factors is necessary to induce the coagulation system during air travel. © 2014 International Society on Thrombosis and Haemostasis.

New models of hemostasis.

PubMed

McMichael, Maureen

2012-05-01

Hemostasis is an essential protective mechanism that depends on a delicate balance of procoagulant and anticoagulant processes. The waterfall/cascade models of coagulation are useful for understanding several essential steps of coagulation in vitro. These have resulted in the creation of the plasma-based tests used commonly and the ability to identify deficiencies in the extrinsic, intrinsic, and common pathways of coagulation. The model was also essential in elucidating the role of several of the inhibitors of coagulation and is currently used to demonstrate coagulation as it occurs in plasma in a static environment that is devoid of endothelial interactions. The intrinsic pathway originally described by these models does not appear to be essential for in vivo hemostasis but may play a role in pathologic thrombosis. The waterfall/cascade models' lack of cellular elements sets the stage for the cell-based model of coagulation. The cell-based model of blood coagulation, which includes the varied, complicated network of factors necessary for appropriate in vivo coagulation to occur, was the next step in the evolution of our understanding of coagulation. Recently, researchers have focused on real-time, in vivo models of hemostasis and this research reveals unexpected phenomena. Copyright © 2012 Elsevier Inc. All rights reserved.

The Organophosphate Paraoxon and Its Antidote Obidoxime Inhibit Thrombin Activity and Affect Coagulation In Vitro

PubMed Central

Golderman, Valery; Shavit-Stein, Efrat; Tamarin, Ilia; Rosman, Yossi; Shrot, Shai; Rosenberg, Nurit

2016-01-01

Organophosphates (OPs) are potentially able to affect serine proteases by reacting with their active site. The potential effects of OPs on coagulation factors such as thrombin and on coagulation tests have been only partially characterized and potential interactions with OPs antidotes such as oximes and muscarinic blockers have not been addressed. In the current study, we investigated the in vitro interactions between coagulation, thrombin, the OP paraoxon, and its antidotes obidoxime and atropine. The effects of these substances on thrombin activity were measured in a fluorescent substrate and on coagulation by standard tests. Both paraoxon and obidoxime but not atropine significantly inhibited thrombin activity, and prolonged prothrombin time, thrombin time, and partial thromboplastin time. When paraoxon and obidoxime were combined, a significant synergistic effect was found on both thrombin activity and coagulation tests. In conclusion, paraoxon and obidoxime affect thrombin activity and consequently alter the function of the coagulation system. Similar interactions may be clinically relevant for coagulation pathways in the blood and possibly in the brain. PMID:27689805

Risk factors associated with short-term outcome and development of perioperative complications in dogs undergoing surgery because of gastric dilatation-volvulus: 166 cases (1992-2003).

PubMed

Beck, Jennifer J; Staatz, Andrew J; Pelsue, Davyd H; Kudnig, Simon T; MacPhail, Catriona M; Seim, Howard B; Monnet, Eric

2006-12-15

To evaluate risk factors associated with death and development of perioperative complications in dogs undergoing surgery for treatment of gastric dilatation-volvulus (GDV). Retrospective case series. 166 dogs. Records of dogs with confirmed GDV that underwent surgery were reviewed. Logistic regression was performed to identify factors associated with development of complications (ie, hypotension, arrhythmias, gastric necrosis necessitating gastrectomy, disseminated intravascular coagulation, peritonitis, sepsis, postoperative dilatation, postoperative vomiting, and incisional problems) and with short-term outcome (ie, died vs survived to the time of suture removal). Short-term mortality rate was 16.2% (27/166). Risk factors significantly associated with death prior to suture removal were clinical signs for > 6 hours prior to examination, combined splenectomy and partial gastrectomy, hypotension at any time during hospitalization, peritonitis, sepsis, and disseminated intravascular coagulation. Partial gastrectomy was not a significant risk factor for death but was for peritonitis, disseminated intravascular coagulation, sepsis, and arrhythmias. Age, gastrectomy, and disseminated intravascular coagulation were risk factors for development of hypotension. Use of a synthetic colloid or hypertonic saline solution was associated with a significantly decreased risk of hypotension. Results suggest that the prognosis for dogs undergoing surgery because of GDV is good but that certain factors are associated with an increased risk that dogs will develop perioperative complications or die.

Thrombin generation and fibrin formation under flow on biomimetic tissue factor-rich surfaces.

PubMed

Onasoga-Jarvis, A A; Puls, T J; O'Brien, S K; Kuang, L; Liang, H J; Neeves, K B

2014-01-01

Blood flow regulates coagulation and fibrin assembly by controlling the rate of transport of zymogens, enzymes and plasma proteins to and from the site of an injury. The objective of this work was to define the hemodynamic conditions under which fibrin can form under flow on tissue factor (TF)-rich substrates. TF-coated silica beads (~ 800 nm) were patterned into 18-85-μm spots. Normal pooled plasma and factors VIII, IX and XI deficient plasmas were perfused over the beads coated with 0.08, 0.8 and 8 molecules-TF μm(-2) at shear rates of 50-1000 s(-1) . Fibrin deposition and thrombin generation were measured by fluorescence microscopy in a hydrodynamic focusing microfluidic device. Fibrin deposition was supported on patterned bead spots, but not planar TF substrates at the same surface TF concentration. There was a threshold spot size and a shear rate dependent TF concentration that was necessary to support fibrin polymerization. FVIII and FIX had minor effects on fibrin dynamics at 8 molecules-TF μm(-2) , but were essential at 0.8 molecules-TF μm(-2) . The absence of FXI influenced thrombin generation and fibrin deposition at both 0.8 and 8 molecules-TF μm(-2) . These results show that fibrin deposition requires perturbations in the flow field that protect reactions from dilution by flow under venous and arterial conditions. FVIII and FIX have a modest effect on fibrin deposition at high TF concentrations, but are necessary for fibrin deposition at low TF concentrations. FXI amplifies thrombin generation under flow at both low and high TF concentrations. © 2013 International Society on Thrombosis and Haemostasis.

Coagulation Management in Jersey Calves: An ex vivo Study.

PubMed

Gröning, Sabine; Maas, Judith; van Geul, Svenja; Rossaint, Rolf; Steinseifer, Ulrich; Grottke, Oliver

2017-01-01

Jersey calves are frequently used as an experimental animal model for in vivo testing of cardiac assist devices or orthopedic implants. In this ex vivo study, we analyzed the coagulation system of the Jersey calves and the potential of human-based coagulation management to circumvent perioperative bleeding complications during surgery. Experimental Procedure: Blood from 7 Jersey calves was subjected to standard laboratory tests and thromboelastometry analysis. An ex vivo model of dilutional coagulopathy was used to study the effects of fibrinogen or prothrombin complex concentrate supplementation. Fibrinolysis was induced with tissue plasminogen activator to identify potential therapeutic strategies involving tranexamic acid or aprotinin. Furthermore, anticoagulation strategies were evaluated by incubating the blood samples with dabigatran or rivaroxaban. Baseline values for thromboelastometry and standard laboratory parameters, including prothrombin time, activated partial thromboplastin time, fibrinogen, antithrombin III, and D-dimers, were established. Fifty percent diluted blood showed a statistically significant impairment of hemostasis. The parameters significantly improved after the administration of fibrinogen or prothrombin complex concentrate. Tranexamic acid and aprotinin ameliorated tissue plasminogen activator-induced fibrinolysis. Both dabigatran and rivaroxaban significantly prolonged the coagulation parameters. In this ex vivo study, coagulation factors, factor concentrate, antifibrinolytic reagents, and anticoagulants regularly used in the clinic positively impacted coagulation parameters in Jersey calf blood. © 2017 S. Karger AG, Basel.

Tissue factor-dependent coagulation activation by heme: A thromboelastometry study.

PubMed

de Souza, Gleice Regina; Hounkpe, Bidossessi Wilfried; Fiusa, Maiara Marx Luz; Colella, Marina Pereira; Annichino-Bizzacchi, Joyce M; Traina, Fabiola; Costa, Fernando Ferreira; De Paula, Erich Vinicius

2017-01-01

Heme has been characterized as potent trigger of inflammation. In hemostasis, although heme has been shown to both induce and inhibit different compartments of hemostasis, its net effect on the hemostatic balance, and the biological relevance of these effects remain to be determined. Herein we evaluated the effect of heme on hemostasis using a global assay able to generate clinically relevant data in several other complex hemostatic diseases. Citrated whole blood samples from healthy participants were stimulated by heme or vehicle and incubated for 4h at 37°C. Rotational thromboelastometry was immediately performed. The participation of tissue factor in coagulation activation was evaluated using inhibitory antibody. Heme was able of inducing ex vivo coagulation activation in whole blood, affecting predominantly parameters associated with the initial phases of clot formation. This activation effect was at least partially dependent on hematopoietic tissue factor, since the effects of heme were partially abrogated by the inhibition of human tissue factor. In conclusion, using a global hemostasis assay, our study confirmed that heme is able to activate coagulation in whole blood, in a tissue factor-dependent way. These findings could explain the disturbance in hemostatic balance observed in conditions associated with the release of heme such as sickle cell disease.

Components in Plasma-Derived Factor VIII, But Not in Recombinant Factor VIII Downregulate Anti-Inflammatory Surface Marker CD163 in Human Macrophages through Release of CXCL4 (Platelet Factor 4).

PubMed

Bertling, Anne; Brodde, Martin F; Visser, Mayken; Treffon, Janina; Fennen, Michelle; Fender, Anke C; Kelsch, Reinhard; Kehrel, Beate E

2017-09-01

Hemarthrosis, or bleeding into the joints, is a hallmark of hemophilia. Heme triggers oxidative stress, inflammation, and destruction of cartilage and bone. The haptoglobin-CD163-heme oxygenase-1 (HO-1) pathway circumvents heme toxicity through enzymatic degradation of heme and transcription of antioxidant genes. Plasma-derived factor concentrates contain many proteins that might impact on cellular pathways in joints, blood, and vessels. Activation of platelets from healthy volunteers was assessed by flow cytometry analysis of fibrinogen binding and CD62P expression. Platelet CXCL4 release was measured by ELISA. Human peripheral blood mononuclear cells were exposed to CXCL4 or platelet supernatants (untreated or pre-stimulated with factor VIII (FVIII) products) during their differentiation to macrophages and analyzed for CD163 expression. Some macrophage cultures were additionally incubated with autologous hemoglobin for 18 h for analysis of HO-1 expression. Platelet CXCL4 release was increased by all 8 tested plasma-derived FVIII products but not the 3 recombinant products. Macrophages exposed to supernatant from platelets treated with some plasma-derived FVIII products downregulated CD163 surface expression and failed to upregulate the athero- and joint protective enzyme HO-1 in response to hemoglobin. Plasma-derived FVIII products might promote bleeding-induced joint injury via generation of macrophages that are unable to counteract redox stress.

Blocking of platelets or intrinsic coagulation pathway-driven thrombosis does not prevent cerebral infarctions induced by photothrombosis.

PubMed

Kleinschnitz, Christoph; Braeuninger, Stefan; Pham, Mirko; Austinat, Madeleine; Nölte, Ingo; Renné, Thomas; Nieswandt, Bernhard; Bendszus, Martin; Stoll, Guido

2008-04-01

Models of photochemically-induced thrombosis are widely used in cerebrovascular research. Photothrombotic brain infarctions can be induced by systemic application of photosensitizing dyes followed by focal illumination of the cerebral cortex. Although the ensuing activation of platelets is well established, their contribution for thrombosis and tissue damage has not formally been proved. Infarction to the cerebral cortex was induced in mice by Rose Bengal and a cold light source. To assess the functional role of platelets, animals were platelet-depleted by anti-GPIbalpha antibodies or treated with GPIIb/IIIa-blocking F(ab)(2) fragments. The significance of the plasmatic coagulation cascade was determined by using blood coagulation factor XII (FXII)-deficient mice or heparin. Infarct development and infarct volumes were determined by serial MRI and conventional and electron microscopy. There was no difference in development and final size of photothrombotic infarctions in mice with impaired platelet function. Moreover, deficiency of FXII, which initiates the intrinsic pathway of coagulation and is essential for thrombus formation, or blockade of FXa, the key protease during the waterfall cascade of plasmatic coagulation, by heparin likewise did not affect lesion development. Our data demonstrate that platelet activation, factor XII-driven thrombus formation, and plasmatic coagulation pathways downstream of FX are not a prerequisite for ensuing tissue damage in models of photothrombotic vessel injury indicating that other pathomechanisms are involved. We suggest that this widely used model does not depend on platelet- or plasmatic coagulation-derived thrombosis.

Clotting and fibrinolytic changes after firefighting activities.

PubMed

Smith, Denise L; Horn, Gavin P; Petruzzello, Steven J; Fahey, George; Woods, Jeffrey; Fernhall, Bo

2014-03-01

Approximately 45%-50% of all duty-related deaths among firefighters are due to sudden cardiovascular events, and a disproportionate number of these fatalities occur after strenuous fire suppression activities. The objective of this study is to evaluate the effect of strenuous firefighting activities on platelets, coagulation, and fibrinolytic activity and to document the extent to which these variables recovered 2 h after completion of the firefighting activity. Firefighters performed 18 min of simulated firefighting activities in a training structure that contained live fires. After firefighting activities, firefighters were provided with fluid and allowed to cool down and then recovered for 2 h in an adjacent room. Blood samples were obtained prefirefighting, postfirefighting, and 2 h postfirefighting. Platelet number, platelet activity, and coagulatory potential increased immediately postfirefighting and many variables (platelet function, partial thromboplastin time, and factor VIII) reflected a procoagulatory state even after 2 h of recovery. Fibrinolysis, as reflected by tissue plasminogen activator, also was enhanced immediately postfirefighting but returned to baseline values by 2 h postfirefighting. In contrast, inhibition of fibrinolysis, as evidenced by a reduction in plasminogen activator inhibitor-1, was depressed at 2 h postfirefighting. Firefighting resulted in elevated coagulatory and fibrinolytic activity. However, 2 h postfirefighting, tissue plasminogen activator returned to baseline and coagulatory potential remained elevated. The procoagulatory state that exists after firefighting may provide a mechanistic link to the reports of sudden cardiac events after strenuous fire suppression activities.

The 'royal disease'--haemophilia A or B? A haematological mystery is finally solved.

PubMed

Lannoy, N; Hermans, C

2010-11-01

  'History can change blood. And blood can change the course of history'. Haemophilia is an illustration of this, as this congenital hereditary coagulation disorder, passed through the majority of royal European families at the beginning of the 20th century by Queen Victoria of England and Empress of the Indies, had indisputable political consequences, which led to one of the most defining moments of contemporary history: the Bolshevik Revolution. Today, none of Queen Victoria's living descendents carry haemophilia. Because of this, the characterization of haemophilia (deficit of either factor VIII or XI) and the identification of the causal mutation are rendered impossible. In 1991, a tomb containing the remains of Czar Nicolas II's entire family was discovered. A second tomb was discovered in 2007, allowing Russian and American scientists to fill in this gap in medical history. Following a scientific approach combining current genetic experimentation tools and the development of biological information technology, researchers were able to identify each body, allowing them to obtain precious genetic material from the young Czar Alexis, who was stricken by the disease, which revealed a causal substitution in the splice acceptor site of exon 4 in the F9 gene. This mutation that is responsible for haemophilia B had traumatized European royal families throughout the 20th century! © 2010 Blackwell Publishing Ltd.

Effects of FVIII immunity on hepatocyte and hematopoietic stem cell–directed gene therapy of murine hemophilia A

PubMed Central

Lytle, Allison M; Brown, Harrison C; Paik, Na Yoon; Knight, Kristopher A; Wright, J Fraser; Spencer, H Trent; Doering, Christopher B

2016-01-01

Immune responses to coagulation factors VIII (FVIII) and IX (FIX) represent primary obstacles to hemophilia treatment. Previously, we showed that hematopoietic stem cell (HSC) retroviral gene therapy induces immune nonresponsiveness to FVIII in both naive and preimmunized murine hemophilia A settings. Liver-directed adeno-associated viral (AAV)-FIX vector gene transfer achieved similar results in preclinical hemophilia B models. However, as clinical immune responses to FVIII and FIX differ, we investigated the ability of liver-directed AAV-FVIII gene therapy to affect FVIII immunity in hemophilia A mice. Both FVIII naive and preimmunized mice were administered recombinant AAV8 encoding a liver-directed bioengineered FVIII expression cassette. Naive animals receiving high or mid-doses subsequently achieved near normal FVIII activity levels. However, challenge with adjuvant-free recombinant FVIII induced loss of FVIII activity and anti-FVIII antibodies in mid-dose, but not high-dose AAV or HSC lentiviral (LV) vector gene therapy cohorts. Furthermore, unlike what was shown previously for FIX gene transfer, AAV-FVIII administration to hemophilia A inhibitor mice conferred no effect on anti-FVIII antibody or inhibitory titers. These data suggest that functional differences exist in the immune modulation achieved to FVIII or FIX in hemophilia mice by gene therapy approaches incorporating liver-directed AAV vectors or HSC-directed LV. PMID:26909355

The acute effect of moderate intensity aquatic exercise on coagulation factors in haemophiliacs.

PubMed

Beltrame, Luis Gustavo Normanton; Abreu, Laurinda; Almeida, Jussara; Boullosa, Daniel Alexandre

2015-05-01

The objective of this cross-sectional study was to analyse the acute effect of aquatic exercise on haemostasis in persons with haemophilia. Ten adult haemophiliacs (8 type A, 2 type B) familiarized with aquatic training performed a 20-min exercise session in a swimming pool at an intensity of ~70% maximum heart rate (HR). Blood samples were collected immediately after the training session. The haemostatic parameters selected for analyses were factor VIII (FVIII), prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen. There were unclear effects of the exercise bout on FVIII and APTT, with a possibly beneficial effect on PT (-11·4%; 90% confidence interval: -26·1;3·3%), and a trivial change on fibrinogen levels. It was found an association between the mean rise in HR during exercise and the decrement in PT after exercise (r = 0·729; P = 0·026). The greater changes were observed in the patients diagnosed with a moderate level of haemophilia. It is concluded that a short bout of moderate intensity of aquatic exercise may have a positive influence on PT in adults with haemophilia with greater changes in those individuals exhibiting a greater rise in HR during exercise. This may be an important issue to the haemostatic control of haemophiliacs in clinical settings. Further studies are warranted for testing the influence of different aquatic exercise intensities on haemostasis. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Evaluation of current and new biomarkers in severe preeclampsia: a microarray approach reveals the VSIG4 gene as a potential blood biomarker.

PubMed

Textoris, Julien; Ivorra, Delphine; Ben Amara, Amira; Sabatier, Florence; Ménard, Jean-Pierre; Heckenroth, Hélène; Bretelle, Florence; Mege, Jean-Louis

2013-01-01

Preeclampsia is a placental disease characterized by hypertension and proteinuria in pregnant women, and it is associated with a high maternal and neonatal morbidity. However, circulating biomarkers that are able to predict the prognosis of preeclampsia are lacking. Thirty-eight women were included in the current study. They consisted of 19 patients with preeclampsia (13 with severe preeclampsia and 6 with non-severe preeclampsia) and 19 gestational age-matched women with normal pregnancies as controls. We measured circulating factors that are associated with the coagulation pathway (including fibrinogen, fibronectin, factor VIII, antithrombin, protein S and protein C), endothelial activation (such as soluble endoglin and CD146), and the release of total and platelet-derived microparticles. These markers enabled us to discriminate the preeclampsia condition from a normal pregnancy but were not sufficient to distinguish severe from non-severe preeclampsia. We then used a microarray to study the transcriptional signature of blood samples. Preeclampsia patients exhibited a specific transcriptional program distinct from that of the control group of women. Interestingly, we also identified a severity-related transcriptional signature. Functional annotation of the upmodulated signature in severe preeclampsia highlighted two main functions related to "ribosome" and "complement". Finally, we identified 8 genes that were specifically upmodulated in severe preeclampsia compared with non-severe preeclampsia and the normotensive controls. Among these genes, we identified VSIG4 as a potential diagnostic marker of severe preeclampsia. The determination of this gene may improve the prognostic assessment of severe preeclampsia.

Classification and regression tree analysis vs. multivariable linear and logistic regression methods as statistical tools for studying haemophilia.

PubMed

Henrard, S; Speybroeck, N; Hermans, C

2015-11-01

Haemophilia is a rare genetic haemorrhagic disease characterized by partial or complete deficiency of coagulation factor VIII, for haemophilia A, or IX, for haemophilia B. As in any other medical research domain, the field of haemophilia research is increasingly concerned with finding factors associated with binary or continuous outcomes through multivariable models. Traditional models include multiple logistic regressions, for binary outcomes, and multiple linear regressions for continuous outcomes. Yet these regression models are at times difficult to implement, especially for non-statisticians, and can be difficult to interpret. The present paper sought to didactically explain how, why, and when to use classification and regression tree (CART) analysis for haemophilia research. The CART method is non-parametric and non-linear, based on the repeated partitioning of a sample into subgroups based on a certain criterion. Breiman developed this method in 1984. Classification trees (CTs) are used to analyse categorical outcomes and regression trees (RTs) to analyse continuous ones. The CART methodology has become increasingly popular in the medical field, yet only a few examples of studies using this methodology specifically in haemophilia have to date been published. Two examples using CART analysis and previously published in this field are didactically explained in details. There is increasing interest in using CART analysis in the health domain, primarily due to its ease of implementation, use, and interpretation, thus facilitating medical decision-making. This method should be promoted for analysing continuous or categorical outcomes in haemophilia, when applicable. © 2015 John Wiley & Sons Ltd.

Contact Activation of Blood Plasma and Factor XII by Ion-exchange Resins

PubMed Central

Yeh, Chyi-Huey Josh; Dimachkie, Ziad O.; Golas, Avantika; Cheng, Alice; Parhi, Purnendu; Vogler, Erwin A.

2011-01-01

Sepharose ion-exchange particles bearing strong Lewis acid/base functional groups (sulfopropyl, carboxymethyl, quarternary ammonium, dimethyl aminoethyl, and iminodiacetic acid) exhibiting high plasma protein adsorbent capacities are shown to be more efficient activators of blood factor XII in neat-buffer solution than either hydrophilic clean-glass particles or hydrophobic octyl sepharose particles ( FXII→surfaceactivatorFXIIa; a.k.a autoactivation, where FXII is the zymogen and FXIIa is a procoagulant protease). In sharp contrast to the clean-glass standard of comparison, ion-exchange activators are shown to be inefficient activators of blood plasma coagulation. These contrasting activation properties are proposed to be due to the moderating effect of plasma-protein adsorption on plasma coagulation. Efficient adsorption of blood plasma proteins unrelated to the coagulation cascade impedes FXII contacts with ion-exchange particles immersed in plasma, reducing autoactivation, and causing sluggish plasma coagulation. By contrast, plasma proteins do not adsorb to hydrophilic clean glass and efficient autoactivation leads directly to efficient activation of plasma coagulation. It is also shown that competitive-protein adsorption can displace FXIIa adsorbed to the surface of ion-exchange resins. As a consequence of highly-efficient autoactivation and FXIIa displacement by plasma proteins, ion-exchange particles are slightly more efficient activators of plasma coagulation than hydrophobic octyl sepharose particles that do not bear strong Lewis acid/base surface functionalities but to which plasma proteins adsorb efficiently. Plasma proteins thus play a dual role in moderating contact activation of the plasma coagulation cascade. The principal role is impeding FXII contact with activating surfaces but this same effect can displace FXIIa from an activating surface into solution where the protease can potentiate subsequent steps of the plasma coagulation cascade. PMID:21982294

Coagulation Imbalance and Neurocognitive Functioning in Older HIV+ Adults on Suppressive Antiretroviral Therapy

PubMed Central

Montoya, Jessica l.; Iudicello, Jennifer; Oppenheim, Hannah A.; Fazeli, Pariya l.; Potter, Michael; MA, Qing; Mills, Paul J.; Ellis, Ronald J.; Grant, Igor; Letendre, Scott l.; Moore, David J.

2017-01-01

Objectives To compare plasma biomarkers of coagulation between HIV-infected individuals and HIV-uninfected controls and to assess the impact of disturbances in coagulation on neurocognitive functioning in HIV. Design Cross-sectional study of 66 antiretroviral therapy-treated virally suppressed HIV-infected and 34 HIV-uninfected older (≥50 years of age) adults. Methods Participants completed standardized neurobehavioral and neuromedical assessments. Neurocognitive functioning was evaluated using a well-validated comprehensive neuropsychological battery. Plasma biomarkers associated with procoagulation (fibrinogen, p-selectin, tissue factor, and von Willebrand factor), anticoagulation (antithrombin, protein C, and thrombomodulin), fibrinolysis (d-dimer, plasminogen activator inhibitor-1, and plasminogen) were collected. Multivariable linear regression was used to test the interaction of HIV and coagulation on neurocognitive functioning. Results Most participants were male (78.0%) and non-Hispanic white (73.0%) with a mean age of 57.8 years. Among HIV-infected participants, mean estimated duration of HIV infection was 19.4 years and median current CD4+ cell count was 654 cells/mm3. Levels of soluble biomarkers of procoagulation, anticoagulation, and fibrinolysis were comparable between the HIV serostatus groups. Coagulation and HIV had an interacting effect on neurocognitive functioning, such that greater coagulation imbalance was associated with poorer neurocognitive functioning among the HIV-infected participants. The moderating effect of coagulation on neurocognition was driven by procoagulant but not anticoagulant or fibrinolytic biomarkers. Conclusions Elevated levels of procoagulants may exert a particularly detrimental effect on neurocognitive functioning among older HIV-infected persons. A better understanding of the specific role of coagulation in the etiology of HIV-associated neurocognitive disorders may lead to treatments aimed at reducing coagulopathy, thereby improving neurocognitive outcomes. PMID:28099190

Coagulation imbalance and neurocognitive functioning in older HIV-positive adults on suppressive antiretroviral therapy.

PubMed

Montoya, Jessica L; Iudicello, Jennifer; Oppenheim, Hannah A; Fazeli, Pariya L; Potter, Michael; Ma, Qing; Mills, Paul J; Ellis, Ronald J; Grant, Igor; Letendre, Scott L; Moore, David J

2017-03-27

The aim of this study was to compare plasma biomarkers of coagulation between HIV-infected individuals and HIV-uninfected controls and to assess the impact of disturbances in coagulation on neurocognitive functioning in HIV. A cross-sectional study of 66 antiretroviral therapy treated, virally suppressed, HIV-infected and 34 HIV-uninfected older (≥50 years of age) adults. Participants completed standardized neurobehavioral and neuromedical assessments. Neurocognitive functioning was evaluated using a well validated comprehensive neuropsychological battery. Plasma biomarkers associated with procoagulation (fibrinogen, p-selectin, tissue factor and von Willebrand factor), anticoagulation (antithrombin, protein C and thrombomodulin), fibrinolysis (d-dimer, plasminogen activator inhibitor-1 and plasminogen) were collected. Multivariable linear regression was used to test the interaction of HIV and coagulation on neurocognitive functioning. Most participants were male (78.0%) and non-Hispanic white (73.0%) with a mean age of 57.8 years. Among HIV-infected participants, mean estimated duration of HIV infection was 19.4 years and median current CD4 cell count was 654 cells/μl. Levels of soluble biomarkers of procoagulation, anticoagulation and fibrinolysis were comparable between the HIV serostatus groups. Coagulation and HIV had an interacting effect on neurocognitive functioning, such that greater coagulation imbalance was associated with poorer neurocognitive functioning among the HIV-infected participants. The moderating effect of coagulation on neurocognition was driven by procoagulant but not anticoagulant or fibrinolytic biomarkers. Elevated levels of procoagulants may exert a particularly detrimental effect on neurocognitive functioning among older HIV-infected persons. A better understanding of the specific role of coagulation in the cause of HIV-associated neurocognitive disorders may lead to treatments aimed at reducing coagulopathy, thereby improving neurocognitive outcomes.

Recombinant factor VIII Fc fusion protein for immune tolerance induction in patients with severe haemophilia A with inhibitors-A retrospective analysis.

PubMed

Carcao, M; Shapiro, A; Staber, J M; Hwang, N; Druzgal, C; Lieuw, K; Belletrutti, M; Thornburg, C D; Ahuja, S P; Morales-Arias, J; Dumont, J; Miyasato, G; Tsao, E; Jain, N; Pipe, S W

2018-03-01

Immune tolerance induction (ITI) is the gold standard for eradication of factor VIII inhibitors in severe haemophilia A; however, it usually requires treatment for extended periods with associated high burden on patients and healthcare resources. Review outcomes of ITI with recombinant factor VIII Fc fusion protein (rFVIIIFc) in patients with severe haemophilia A and high-titre inhibitors. Multicentre retrospective chart review of severe haemophilia A patients treated with rFVIIIFc for ITI. Of 19 patients, 7 were first-time ITI and 12 were rescue ITI. Of 7 first-time patients, 6 had at least 1 high-risk feature for ITI failure. Four of 7 first-time patients were tolerized in a median of 7.8 months. The remaining 3 patients continue on rFVIIIFc ITI. Of 12 rescue patients, 7 initially achieved a negative Bethesda titre (≤0.6) in a median of 3.3 months, 1 had a decrease in Bethesda titre and continues on rFVIIIFc ITI and 4 have not demonstrated a decrease in Bethesda titre. Of these 4, 3 continue on rFVIIIFc ITI and 1 switched to bypass therapy alone. Two initially responsive patients transitioned to other factors due to recurrence. Overall, 16 of 19 patients remain on rFVIIIFc (prophylaxis or ITI). For those still undergoing ITI, longer follow-up is needed to determine final outcomes. No adverse events reported. Recombinant factor VIII Fc fusion protein demonstrated rapid time to tolerization in high-risk first-time ITI patients. For rescue ITI, rFVIIIFc showed therapeutic benefit in some patients who previously failed ITI with other products. These findings highlight the need to further evaluate the use of rFVIIIFc for ITI. © 2018 The Authors. Haemophilia Published by John Wiley & Sons Ltd.

Imaging of blood plasma coagulation at supported lipid membranes.

PubMed

Faxälv, Lars; Hume, Jasmin; Kasemo, Bengt; Svedhem, Sofia

2011-12-15

The blood coagulation system relies on lipid membrane constituents to act as regulators of the coagulation process upon vascular trauma, and in particular the 2D configuration of the lipid membranes is known to efficiently catalyze enzymatic activity of blood coagulation factors. This work demonstrates a new application of a recently developed methodology to study blood coagulation at lipid membrane interfaces with the use of imaging technology. Lipid membranes with varied net charges were formed on silica supports by systematically using different combinations of lipids where neutral phosphocholine (PC) lipids were mixed with phospholipids having either positively charged ethylphosphocholine (EPC), or negatively charged phosphatidylserine (PS) headgroups. Coagulation imaging demonstrated that negatively charged SiO(2) and membrane surfaces exposing PS (obtained from liposomes containing 30% of PS) had coagulation times which were significantly shorter than those for plain PC membranes and EPC exposing membrane surfaces (obtained from liposomes containing 30% of EPC). Coagulation times decreased non-linearly with increasing negative surface charge for lipid membranes. A threshold value for shorter coagulation times was observed below a PS content of ∼6%. We conclude that the lipid membranes on solid support studied with the imaging setup as presented in this study offers a flexible and non-expensive solution for coagulation studies at biological membranes. It will be interesting to extend the present study towards examining coagulation on more complex lipid-based model systems. Copyright © 2011 Elsevier Inc. All rights reserved.

Fish as bioreactors: transgene expression of human coagulation factor VII in fish embryos.

PubMed

Hwang, Gyulin; Müller, Ferenc; Rahman, M Aziz; Williams, Darren W; Murdock, Paul J; Pasi, K John; Goldspink, Geoffrey; Farahmand, Hamid; Maclean, Norman

2004-01-01

A plasmid containing human coagulation factor VII (hFVII) complementary DNA regulated by a cytomegalovirus promoter was microinjected into fertilized eggs of zebrafish, African catfish, and tilapia. The active form of hFVll was detected in the fish embryos by various assays. This positive expression of human therapeutic protein in fish embryos demonstrates the possibility of exploitation of transgenic fish as bioreactors.

Nanoparticles and the blood coagulation system. Part II: safety concerns

PubMed Central

Ilinskaya, Anna N; Dobrovolskaia, Marina A

2014-01-01

Nanoparticle interactions with the blood coagulation system can be beneficial or adverse depending on the intended use of a nanomaterial. Nanoparticles can be engineered to be procoagulant or to carry coagulation-initiating factors to treat certain disorders. Likewise, they can be designed to be anticoagulant or to carry anticoagulant drugs to intervene in other pathological conditions in which coagulation is a concern. An overview of the coagulation system was given and a discussion of a desirable interface between this system and engineered nanomaterials was assessed in part I, which was published in the May 2013 issue of Nanomedicine. Unwanted pro- and anti-coagulant properties of nanoparticles represent significant concerns in the field of nanomedicine, and often hamper the development and transition into the clinic of many promising engineered nanocarriers. This part will focus on the undesirable effects of engineered nanomaterials on the blood coagulation system. We will discuss the relationship between the physicochemical properties of nanoparticles (e.g., size, charge and hydrophobicity) that determine their negative effects on the blood coagulation system in order to understand how manipulation of these properties can help to overcome unwanted side effects. PMID:23730696

On coagulation mechanisms of charged nanoparticles produced by combustion of hydrocarbon and metallized fuels

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

Savel'ev, A. M.; Starik, A. M.

2009-02-15

The contributions of van der Waals, Coulomb, and polarization interactions between nanometersized particles to the particle coagulation rate in both free-molecular and continuum regimes are analyzed for particle charges of various magnitudes and signs. Analytical expressions are obtained for the coagulation rate constant between particles whose interaction in the free-molecular regime is described by a singular potential. It is shown that van der Waals and polarization forces significantly increase the coagulation rate between a neutral and a charged particle (by a factor of up to 10) and can even suppress the Coulomb repulsion between like-charged particles of widely different sizes.

Diagnostic Error of a Patient with Combined Inherited Factor VII and Factor X Deficiency due to Accidental Ingestion of a Diphacinone Rodenticide.

PubMed

Li, Min; Jin, Yanhui; Wang, Mingshan; Xie, Yaosheng; Ding, Hongxiang

2016-11-01

To explore the characteristics of laboratory examination and confirm the diagnosis of a patient with combined inherited FVII and FX deficiency after he ingested diphacinone rodenticide accidentally. The coagulant parameter screening tests and coagulation factor activities were tested many times in the patient due to accidental ingestion of a diphacinone rodenticide. After the patient was treated for more than one year, gene analysis of correlated coagulation factors was analyzed in the patient and other family members by DNA direct sequencing. 106 persons were selected as controls from routine health examinations. After the patient was admitted to hospital, routine coagulation screening tests revealed the prolonged prothrombin time (PT) and activated partial thromboplastin time (APTT) and low levels of vitamin K-dependent coagulation factors (FII, FVII, FIX, FX) activity, which was 102.4 seconds, 88.5 seconds, 7%, 3%, 8%, and 2%, respectively. During more than one year of treatment, the value of PT and APTT still showed significantly prolonged activity and FVII and FX activity levels were about 5%. While FII and FIX activity levels were in the normal range after 12 weeks of treatment. Two homozygous mutations, g.11267C>T of F7 gene resulting in the substitution Arg277Cys and g.28139G>T of F10 gene leading to the substitution Val384Phe, were identified in the patient. The patient's parents and sister was heterozygous for Arg277Cys and Val384Phe mutations. FVII and FX antigen levels in the patient were 7% and 30%, respectively. There were many similarities in the characteristics of laboratory examination between combined inherited FVII and FX deficiency and acquired vitamin K deficiency. The best way to identify them was gene analysis.

Activation of blood coagulation in cancer: implications for tumour progression

PubMed Central

Lima, Luize G.; Monteiro, Robson Q.

2013-01-01

Several studies have suggested a role for blood coagulation proteins in tumour progression. Herein, we discuss (1) the activation of the blood clotting cascade in the tumour microenvironment and its impact on primary tumour growth; (2) the intravascular activation of blood coagulation and its impact on tumour metastasis and cancer-associated thrombosis; and (3) antitumour therapies that target blood-coagulation-associated proteins. Expression levels of the clotting initiator protein TF (tissue factor) have been correlated with tumour cell aggressiveness. Simultaneous TF expression and PS (phosphatidylserine) exposure by tumour cells promote the extravascular activation of blood coagulation. The generation of blood coagulation enzymes in the tumour microenvironment may trigger the activation of PARs (protease-activated receptors). In particular, PAR1 and PAR2 have been associated with many aspects of tumour biology. The procoagulant activity of circulating tumour cells favours metastasis, whereas the release of TF-bearing MVs (microvesicles) into the circulation has been correlated with cancer-associated thrombosis. Given the role of coagulation proteins in tumour progression, it has been proposed that they could be targets for the development of new antitumour therapies. PMID:23889169

A small amount can make a difference: a prospective human study of the paradoxical coagulation characteristics of hemothorax.

PubMed

Smith, W Zachary; Harrison, Hannah B; Salhanick, Marc A; Higgins, Russell A; Ortiz, Alfonso; Olson, John D; Schwacha, Martin G; Harrison, Chantal R; Aydelotte, Jayson D; Stewart, Ronald M; Dent, Daniel L

2013-12-01

The evacuated hemothorax has been poorly described because it varies with time, it has been found to be incoagulable, and its potential effect on the coagulation cascade during autotransfusion is largely unknown. This is a prospective descriptive study of adult patients with traumatic chest injury necessitating tube thoracostomy. Pleural and venous samples were analyzed for coagulation, hematology, and electrolytes at 1 to 4 hours after drainage. Pleural samples were also analyzed for their effect on the coagulation cascade via mixing studies. Thirty-four subjects were enrolled with a traumatic hemothorax. The following measured coagulation factors were significantly depleted compared with venous blood: international normalized ratio (>9 vs 1.1) (P < .001) and activated partial thromboplastin time (aPTT) (>180 vs 24.5 seconds) (P < .001). Mixing studies showed a dose-dependent increase in coagulation dilutions through 1:8 (P < .05). An evacuated hemothorax does not vary in composition significantly with time and is incoagulable alone. Mixing studies with hemothorax plasma increased coagulation, raising safety concerns. Copyright © 2013 Elsevier Inc. All rights reserved.

Influential factors of formation kinetics of flocs produced by water treatment coagulants.

PubMed

Wu, Chunde; Wang, Lin; Hu, Bing; Ye, Jian

2013-05-01

The growth rate and size of floc formation is of great importance in water treatment especially in coagulation process. The floc formation kinetics and the coagulation efficiency of synthetic water were investigated by using an on-line continuous optical photometric dispersion analyze and the analysis of water quality. Experimental conditions such as alum dosage, pH value for coagulation, stirring intensity and initial turbidity were extensively examined. The photometric dispersion analyze results showed that coagulation of kaolin suspensions with two coagulants (alum and polyaluminium chloride) could be taken as a two-phase process: slow and rapid growth periods. Operating conditions with higher coagulant doses, appropriate pH and average shear rate might be particularly advantageous. The rate of overall floc growth was mainly determined by a combination of hydraulic and water quality conditions such as pH and turbidity. The measurement of zeta potential indicates that polyaluminium chloride exhibited higher charge-neutralizing ability than alum and achieved lower turbidities than alum for equivalent Al dosages. Under the same operating conditions, the alum showed a higher grow rate, but with smaller floc size.

Initial Resuscitation with Plasma and Other Blood Components Reduced Bleeding Compared to Hetastarch in Anesthetized Swine with Uncontrolled Splenic Hemorrhage

DTIC Science & Technology

2011-04-01

products and Hextend. The fluid with the highest amount of coagulation factors , FFP resulted in the lowest blood loss. The FFP treatment had the highest...compared to humans and have higher concentrations of many of the clotting factors (FV, FVII , FVIII, F IX, and FXII).44 Although we have confirmed the higher...utilizing plasma early in treatment is to prevent dilution of remaining coagulation factors or reverse the coagulopathy that has been observed in

Therapeutic Correction of Thrombin Generation in Dilution-Induced Coagulopathy: Computational Analysis Based on a Data Set of Healthy Subjects

DTIC Science & Technology

2012-01-01

Factor VIIa tended to primarily impact clotting time, thrombin peak time, and maximum slope of the thrombin curve, whereas in the case of PCC- FVII ...constituents of existing PCCs are the four coagulation factors (F) II (prothrombin), FVII , FIX, and FX.3 Notably, FVII inhibits thrombin generation by...proposed PCC composition (coagulation factors [F] II, IX, and X and the anticoagulant antithrombin), designated PCC-AT, was compared with that of

Soluble Proteins Form Film by the Treatment of Low Temperature Plasma

NASA Astrophysics Data System (ADS)

Ikehara, Sanae; Sakakita, Hajime; Ishikawa, Kenji; Akimoto, Yoshihiro; Nakanishi, Hayao; Shimizu, Nobuyuki; Hori, Masaru; Ikehara, Yuzuru

2015-09-01

It has been pointed out that low temperature plasma in atmosphere was feasible to use for hemostasis without heat injury. Indeed, earlier studies demonstrated that low temperature plasma played an important role to stimulate platelets to aggregate and turned on the proteolytic activities of coagulation factors, resulting in the acceleration of the natural blood coagulation process. On the other hands, our developed equips could immediately form clots upon the contact with plasma flair, while the histological appearance was different from natural coagulation. Based on these findings in formed clots, we sought to determine if plasma flair supplied by our devices was capable of forming film using a series of soluble proteins Following plasma treatment, films were formed from bovine serum albumin, and the other plasma proteins at physiological concentration. Analysis of trans-electron microscope demonstrated that plasma treatment generated small protein particles and made them fuse to be larger aggregations The combined results demonstrated that plasma are capable of aggregating soluble proteins and that platelets and coagulation factors are not necessary for plasma induced blood coagulation. Supported in part by Grants-in-Aid for Scientific Research on Priority Area (21590454, 24590498, and 24108006 to Y. I.).

Risk factors for disseminated intravascular coagulation in patients with lung cancer.

PubMed

Nakano, Kentaro; Sugiyama, Kumiya; Satoh, Hideyuki; Shiromori, Sadaaki; Sugitate, Kei; Arifuku, Hajime; Yoshida, Naruo; Watanabe, Hiroyoshi; Tokita, Shingo; Wakayama, Tomoshige; Tatewaki, Masamitsu; Souma, Ryosuke; Koyama, Kenya; Hirata, Hirokuni; Fukushima, Yasutsugu

2018-05-31

The mortality rate from disseminated intravascular coagulation (DIC) is higher in patients with lung cancer than in non-lung cancer patients. Moreover, the prevalence of DIC varies among the pathologic types of lung cancer. This study analyzed the relationship between coagulation factors and the pathologic types of lung cancer. Twenty-six patients with progressive, inoperable stage IIB or higher lung cancer (20 men, 6 women; mean age 71 years; 11 Adeno, 10 squamous cell carcinoma, and 5 small cell carcinoma) and five healthy volunteers without respiratory disease (3 men, 2 women; mean age 72 years) were enrolled in the study. Blood samples were collected at lung cancer diagnosis, before treatment. White blood cell count, platelet count, serum C-reactive protein, fibrin/fibrinogen degradation products, fibrinogen, thrombin-antithrombin complex, and D-dimer levels differed significantly between lung cancer patients and the control group, but not among the pathologic types of lung cancer. Thrombomodulin levels were significantly higher in patients with Adeno and squamous cell carcinoma than in those with small cell carcinoma (P < 0.05 and P < 0.01, respectively). Antithrombin levels were significantly lower in patients with squamous cell carcinoma than in those with Adeno (P < 0.05). Coagulation disorders may develop secondary to chronic inflammation in patients with progressive lung cancer. DIC in lung cancer may be attributed to changes in anticoagulation factors, such as thrombomodulin and antithrombin, but not in other coagulation factors. © 2018 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

Isolation and partial purification of anticoagulant fractions from the venom of the Iranian snake Echis carinatus.

PubMed

Babaie, Mahdi; Zolfagharian, Hossein; Salmanizadeh, Hossein; Mirakabadi, Abbas Zare; Alizadeh, Hafezeh

2013-01-01

Many snake venoms comprise different factors, which can either promote or inhibit the blood coagulation pathway. Coagulation disorders and hemorrhage belong to the most prominent features of bites of the many vipers. A number of these factors interact with components of the human blood coagulation. This study is focused on the effect of Echis carinatus snake venom on blood coagulation pathway. Anticoagulant factors were purified from the Iranian Echis carinatus venom by two steps: gel filtration (Sephadex G-75) and ion-exchange (DEAE-Sephadex) chromatography, in order to study the anticoagulant effect of crude venom and their fractions. The prothrombin time was estimated on human plasma for each fraction. Our results showed that protrombin time value was increase from 13.4 s to 170 s for F2C and to 280 s for F2D. Our study showed that these fractions of the venom delay the prothrombine time and thus can be considered as anticoagulant factors. They were shown to exhibit proteolytic activity. The molecular weights of these anticoagulants (F2C, F2D) were estimated by SDS/PAGE electrophoresis. F2C comprises two protein bands with molecular weights of 50 and 79 kDa and F2D a single band with a molecular weight of 42 kDa.

A Joint Model for Vitamin K-Dependent Clotting Factors and Anticoagulation Proteins.

PubMed

Ooi, Qing Xi; Wright, Daniel F B; Tait, R Campbell; Isbister, Geoffrey K; Duffull, Stephen B

2017-12-01

Warfarin acts by inhibiting the reduction of vitamin K (VK) to its active form, thereby decreasing the production of VK-dependent coagulation proteins. The aim of this research is to develop a joint model for the VK-dependent clotting factors II, VII, IX and X, and the anticoagulation proteins, proteins C and S, during warfarin initiation. Data from 18 patients with atrial fibrillation who had warfarin therapy initiated were available for analysis. Nine blood samples were collected from each subject at baseline, and at 1-5, 8, 15 and 29 days after warfarin initiation and assayed for factors II, VII, IX and X, and proteins C and S. Warfarin concentration-time data were not available. The coagulation proteins data were modelled in a stepwise manner using NONMEM ® Version 7.2. In the first stage, each of the coagulation proteins was modelled independently using a kinetic-pharmacodynamic model. In the subsequent step, the six kinetic-pharmacodynamic models were combined into a single joint model. One patient was administered VK and was excluded from the analysis. Each kinetic-pharmacodynamic model consisted of two parts: (1) a common one-compartment pharmacokinetic model with first-order absorption and elimination for warfarin; and (2) an inhibitory E max model linked to a turnover model for coagulation proteins. In the joint model, an unexpected pharmacodynamic lag was identified and the estimated degradation half-life of VK-dependent coagulation proteins were in agreement with previously published values. The model provided an adequate fit to the observed data. The joint model represents the first work to quantify the influence of warfarin on all six VK-dependent coagulation proteins simultaneously. Future work will expand the model to predict the influence of exogenously administered VK on the time course of clotting factor concentrations after warfarin overdose and during perioperative warfarin reversal procedures.

Development of a microplate coagulation assay for Factor V in human plasma.

PubMed

Tilley, Derek; Levit, Irina; Samis, John A

2011-06-28

Factor V (FV) in its activated form, FVa, is a critical regulator of thrombin generation during fibrin clot formation. There is a need of a simple, fast, and inexpensive microplate-based coagulation assay to measure the functional activity of FV in human plasma. The objective of this study was to develop a microplate-based assay that measures FV coagulation activity during clot formation in human plasma, which is currently not available. The FV assay requires a kinetic microplate reader to measure the change in absorbance at 405nm during fibrin formation in human plasma. The FV assay accurately measures the time, initial rate, and extent of fibrin clot formation in human plasma. The FV microplate assay is simple, fast, economical, sensitive to approx 24-80pM, and multiple samples may be analyzed simultaneously. All the required materials are commercially available. Standard curves of time or initial rate of fibrin clot formation vs FV activity in the 1-stage assay (Without activation by thrombin) may be used to measure FV activity in samples of human plasma. The assay was used to demonstrate that in nine patients with disseminated intravascular coagulation (DIC), the FV 1-stage, 2-stage (With activation by thrombin), and total (2-stage activity - 1-stage activity) activities were decreased, on average, by approximately 54%, 44%, and 42%, respectively, from prolonged clot times when compared to normal pooled human reference plasma (NHP). The results indicate that the FV in the DIC patient plasmas supported both a delayed and slower rate of fibrin clot formation compared with NHP; however, the extent of fibrin clot formation in the DIC patients remained largely unchanged from that observed with NHP. The FV microplate assay may be easily adapted to measure the activity of any coagulation factor using the appropriate factor-deficient plasma and clot initiating reagent. The microplate assay will find use in both research and clinical laboratories to provide measurement of the functional coagulation activity of FV in human plasma.

[Risk factors for the development of venous insufficiency of the lower limbs during pregnancy--part 1].

PubMed

Ropacka-Lesiak, Mariola; Kasperczak, Jarosław; Breborowicz, Grzegorz H

2012-12-01

The venous system alters its function in pregnancy--the changes are both functional and structural. It becomes particularly vulnerable to the development of venous thrombosis and related complications. These adverse factors acting on the veins in pregnancy include: an increase in circulating blood volume, expansion of the uterus, weight gain, reduced physical activity hormonal changes. The changes in the plasma have a significant impact on the venous system. In pregnancy an increased level of fibrinogen and coagulation factors VII, VIII, IX and X, and von Willenbrand factor can be observed. Smooth muscle relaxation and relaxation of collagen fibers are caused by progesterone and estrogen, and it may result in the development of varicose veins, venous thrombosis and venous insufficiency The relationships between the hormones and the muscle pump efficiency has not been proven as yet. Estrogens cause an increase in the synthesis of coagulation proteins and it may result in the high risk of venous thrombosis and its consequences. Progesterone inhibits smooth muscle contraction, while estrogens cause relaxation and loosening of the bonds between the collagen fibers. The increase in the level of progesterone is of particular importance. It has a relaxing effect on the muscle, resulting in disorders of the vein shrinkage, affecting the increase of their capacity and valvular insufficiency, and valvular edges are not in contact with each other due to the vasodilatation. Estrogens have a similar effect, and additionally it may also cause an impairment in the collagen fibers connection and synthesis. This can result in the formation of telanglectasia without venous hypertension. Estrogens may also affect the synthesis of prostaglandins and nitric oxide. Estradiol inhibits vascular smooth muscle cell proliferation and stimulates cell migration and secretion of matrix proteins, as well as regeneration of the damaged vessels. Estrogen inhibits the production of cytokines, adhesion molecules, and reduce platelet response, i.e. the aggregation and adhesion in the presence of monocytes. Estradiol increases the production, activity and bioavailability of nitric oxide, a molecule with a strong vasodilating effect. Additionally adverse affects may appear due to short intervals between pregnancies, genetics, presence of venous thrombosis or venous insufficiency in the superficial and deep system in anamnesis. Caesarean section is also a risk factor for venous thrombosis. Family factors are associated with inheritance of the formation of varicose changes and venous insufficiency in both ways, dominant and recessive, and also sex-related. Among other factors affecting the development of venous insufficiency during pregnancy the following can be distinguished: type of work (standing, sitting, in forced positions and vibration), interval between pregnancies (determining the possibility of regeneration of physiological regeneration of the system). In case of women who were pregnant more than once, the risk of developing varicose veins and other venous insufficiency is doubled.

How Frequency of Electrosurgical Current and Electrode Size Affect the Depth of Electrocoagulation.

PubMed

Taheri, Arash; Mansoori, Parisa; Bahrami, Naeim; Alinia, Hossein; Watkins, Casey E; Feldman, Steven R

2016-02-01

Many factors affect the depth of electrocoagulation. To evaluate the effect of current frequency and electrode size on the depth of electrocoagulation. In this in vitro study, 4 cylindrical electrodes (2, 2.3, 3, and 4 mm) were used to apply 3 electrosurgical currents (0.4, 1.5, and 3 MHz) to bovine liver. Each electrode was placed at different points on the surface of the liver, and energy at various levels and frequencies was delivered to the tissue. Subsequently, cross-sections of the liver were analyzed. Coagulation started at the periphery of the electrode-tissue contact area. With higher energy levels, coagulation spreads to involve the remainder of the contact area. Neither the frequency nor the electrode size had any effect on this coagulation pattern. The frequency of the current also did not show any relation with depth of coagulation; however, there was a direct correlation between the size of the electrode and the depth of coagulation. Larger-tip electrodes provided deeper coagulation compared with finer-tip electrodes.

Life-threatening urethral hemorrhage after placement of a Foley catheter in a patient with uroseptic disseminated intravascular coagulation due to chronic urinary retention induced by untreated benign prostatic hyperplasia.

PubMed

Ikegami, Yukihiro; Yoshida, Keisuke; Imaizumi, Tsuyoshi; Isosu, Tsuyoshi; Kurosawa, Shin; Murakawa, Masahiro

2016-10-01

A 77-year-old man with severe septic disseminated intravascular coagulation following urinary infection was transported to our hospital. He had developed urinary retention induced by untreated prostatic hyperplasia. Immediate drainage with a Foley catheter was successfully carried out, but the hematuria progressed to life-threatening hemorrhage. Complete hemostasis was impossible by surgical treatment because the tissue around the prostatic urethra was very fragile and hemorrhagic. Organized treatments (continuous hemodiafiltration combined with polymyxin-B immobilized fiber column hemoperfusion and systemic treatment with antibiotics and coagulation factors) were commenced soon after the operation. The patient eventually recovered from the septic disseminated intravascular coagulation. This case report illustrates the risk of placement of Foley catheters in patients with severe septic disseminated intravascular coagulation.

Components in Plasma-Derived Factor VIII, But Not in Recombinant Factor VIII Downregulate Anti-Inflammatory Surface Marker CD163 in Human Macrophages through Release of CXCL4 (Platelet Factor 4)

PubMed Central

Bertling, Anne; Brodde, Martin F.; Visser, Mayken; Treffon, Janina; Fennen, Michelle; Fender, Anke C.; Kelsch, Reinhard; Kehrel, Beate E.

2017-01-01

Background Hemarthrosis, or bleeding into the joints, is a hallmark of hemophilia. Heme triggers oxidative stress, inflammation, and destruction of cartilage and bone. The haptoglobin-CD163-heme oxygenase-1 (HO-1) pathway circumvents heme toxicity through enzymatic degradation of heme and transcription of antioxidant genes. Plasma-derived factor concentrates contain many proteins that might impact on cellular pathways in joints, blood, and vessels. Methods Activation of platelets from healthy volunteers was assessed by flow cytometry analysis of fibrinogen binding and CD62P expression. Platelet CXCL4 release was measured by ELISA. Human peripheral blood mononuclear cells were exposed to CXCL4 or platelet supernatants (untreated or pre-stimulated with factor VIII (FVIII) products) during their differentiation to macrophages and analyzed for CD163 expression. Some macrophage cultures were additionally incubated with autologous hemoglobin for 18 h for analysis of HO-1 expression. Results Platelet CXCL4 release was increased by all 8 tested plasma-derived FVIII products but not the 3 recombinant products. Macrophages exposed to supernatant from platelets treated with some plasma-derived FVIII products downregulated CD163 surface expression and failed to upregulate the athero- and joint protective enzyme HO-1 in response to hemoglobin. Conclusion Plasma-derived FVIII products might promote bleeding-induced joint injury via generation of macrophages that are unable to counteract redox stress. PMID:29070980

In Vitro and In Vivo Investigation of High-Intensity Focused Ultrasound (HIFU) Hat-Type Ablation Mode

PubMed Central

Dai, Hongya; Chen, Fei; Yan, Sijing; Ding, Xiaoya; Ma, Dazhao; Wen, Jing; Xu, Die; Zou, Jianzhong

2017-01-01

Background The aim of this study was to investigate the feasibility of the application of high-intensity focused ultrasound (HIFU) hat-type ablation mode in in vitro and in vivo models, and to compare the ablation effects of different parameter combinations. Material/Methods HIFU hat-type ablation was performed in isolated bovine liver tissue and in the liver tissue in living rabbits, and the coagulative necrosis for different parameter combinations (plane angles and irradiation order) was investigated. We also analyzed and compared the ablation effects of traditional ablation and hat-type ablation modes. Coagulative necrosis morphology was detected with TTC staining, and the coagulative necrosis volume and energy efficiency factor (EEF) were calculated and compared. Results Coagulative necrosis was observed in all the ablated groups, and the coagulative necrosis volume was much larger than the irradiation area. The coagulative necrosis induced by the hat-type ablation was more regular and controllable than the traditional ablation. The angles between the ablation planes determined the coagulative necrosis morphology, but did not affect the coagulative necrosis volume. Moreover, the irradiation order significantly influenced the coagulative necrosis. Importantly, under certain conditions, hat-type ablation achieved higher efficiency compared with the traditional ablation mode. Conclusions Compared with the traditional ablation mode, HIFU hat-type ablation effectively shortened the irradiation time, reduced the over-accumulation of energy, and increased the HIFU ablation efficiency. PMID:28699626

In Vitro and In Vivo Investigation of High-Intensity Focused Ultrasound (HIFU) Hat-Type Ablation Mode.

PubMed

Dai, Hongya; Chen, Fei; Yan, Sijing; Ding, Xiaoya; Ma, Dazhao; Wen, Jing; Xu, Die; Zou, Jianzhong

2017-07-12

BACKGROUND The aim of this study was to investigate the feasibility of the application of high-intensity focused ultrasound (HIFU) hat-type ablation mode in in vitro and in vivo models, and to compare the ablation effects of different parameter combinations. MATERIAL AND METHODS HIFU hat-type ablation was performed in isolated bovine liver tissue and in the liver tissue in living rabbits, and the coagulative necrosis for different parameter combinations (plane angles and irradiation order) was investigated. We also analyzed and compared the ablation effects of traditional ablation and hat-type ablation modes. Coagulative necrosis morphology was detected with TTC staining, and the coagulative necrosis volume and energy efficiency factor (EEF) were calculated and compared. RESULTS Coagulative necrosis was observed in all the ablated groups, and the coagulative necrosis volume was much larger than the irradiation area. The coagulative necrosis induced by the hat-type ablation was more regular and controllable than the traditional ablation. The angles between the ablation planes determined the coagulative necrosis morphology, but did not affect the coagulative necrosis volume. Moreover, the irradiation order significantly influenced the coagulative necrosis. Importantly, under certain conditions, hat-type ablation achieved higher efficiency compared with the traditional ablation mode. CONCLUSIONS Compared with the traditional ablation mode, HIFU hat-type ablation effectively shortened the irradiation time, reduced the over-accumulation of energy, and increased the HIFU ablation efficiency.

Broad NE 8 lambda 774 emission from quasars in the HST-FOS snapshot survey (ABSNAP)

NASA Technical Reports Server (NTRS)

Hamann, Fred; Zuo, Lin; Tytler, David

1995-01-01

We discuss the strength and frequency of broad Ne VIII lambda 774 emission from quasars measured in the Hubble Space Telescope Faint Object Spectrograph (HST-FOS) snapshot survey (Absnap). Five sources in the survey have suitable redshifts (0.86 less than or equal to Z(sub em) less than or equal to 1.31), signal-to-noise ratios and no Lyman limit absorptions. Three of the five sources have a strong broad emission line near 774 A (rest), and the remaining two sources have a less securely measured line near this wavelength. We identify these lines with Ne VIII lambda 774 based on the measured wavelengths and theoretical estimates of various line fluxes (Hamann et al. 1995a). Secure Ne VIII detections occur in both radio-loud and radio-quiet sources. We tentatively conclude that broad Ne VIII lambda 774 emission is common in quasars, with typical strengths between approximately 25% and approximately 200% of O VI lambda 1034. These Ne VIII lambda 774 measurements imply that the broad emission line regions have a much hotter and more highly ionized component than previously recognized. They also suggest that quasar continua have substantial ionizing flux out to energies greater than 207 eV (greater than 15.2 ryd, lambda less than 60 A). Photoionization calculations using standard incident spectra indicate that the Ne VIII emission requires ionization parameters U greater than or = 5, total column densities N(sub H) greater than or = 10(sub 22)/sq cm and covering factors greater than or = 25%. The temperatures could be as high as approximately 10(exp 5) K. If the gas is instead collisionally ionized, strong Ne VIII would imply equilibrium temperatures in the range approximately 400,000 less than or approximately = T(sub e) less than or approximately = 10(exp 6) K. In either case, the highly ionized Ne VIII emission regions would appear as X-ray 'warm absorbers' if they lie along our line of sight to the X-ray continuum source.

Chronic sleep deprivation markedly reduces coagulation factor VII expression

PubMed Central

Pinotti, Mirko; Bertolucci, Cristiano; Frigato, Elena; Branchini, Alessio; Cavallari, Nicola; Baba, Kenkichi; Contreras-Alcantara, Susana; Ehlen, J. Christopher; Bernardi, Francesco; Paul, Ketema N.; Tosini, Gianluca

2010-01-01

Chronic sleep loss, a common feature of human life in industrialized countries, is associated to cardiovascular disorders. Variations in functional parameters of coagulation might contribute to explain this relationship. By exploiting the mouse model and a specifically designed protocol, we demonstrated that seven days of partial sleep deprivation significantly decreases (−30.5%) the thrombin generation potential in plasma evaluated upon extrinsic (TF/FVIIa pathway) but not intrinsic activation of coagulation. This variation was consistent with a decrease (−49.8%) in the plasma activity levels of factor VII (FVII), the crucial physiologicalal trigger of coagulation, which was even more pronounced at the liver mRNA level (−85.7%). The recovery in normal sleep conditions for three days completely restored thrombin generation and FVII activity in plasma. For the first time, we demonstrate that chronic sleep deprivation on its own reduces, in a reversible manner, the FVII expression levels, thus influencing the TF/FVIIa activation pathway efficiency. PMID:20418241

Immunosuppression for acquired hemophilia A: results from the European Acquired Haemophilia Registry (EACH2).

PubMed

Collins, Peter; Baudo, Francesco; Knoebl, Paul; Lévesque, Hervé; Nemes, László; Pellegrini, Fabio; Marco, Pascual; Tengborn, Lilian; Huth-Kühne, Angela

2012-07-05

Acquired hemophilia A (AHA) is an autoimmune disease caused by an autoantibody to factor VIII. Patients are at risk of severe and fatal hemorrhage until the inhibitor is eradicated, and guidelines recommend immunosuppression as soon as the diagnosis has been made. The optimal immunosuppressive regimen is unclear; therefore, data from 331 patients entered into the prospective EACH2 registry were analyzed. Steroids combined with cyclophosphamide resulted in more stable complete remission (70%), defined as inhibitor undetectable, factor VIII more than 70 IU/dL and immunosuppression stopped, than steroids alone (48%) or rituximab-based regimens (59%). Propensity score-matched analysis controlling for age, sex, factor VIII level, inhibitor titer, and underlying etiology confirmed that stable remission was more likely with steroids and cyclophosphamide than steroids alone (odds ratio = 3.25; 95% CI, 1.51-6.96; P < .003). The median time to complete remission was approximately 5 weeks for steroids with or without cyclophosphamide; rituximab-based regimens required approximately twice as long. Immunoglobulin administration did not improve outcome. Second-line therapy was successful in approximately 60% of cases that failed first-line therapy. Outcome was not affected by the choice of first-line therapy. The likelihood of achieving stable remission was not affected by underlying etiology but was influenced by the presenting inhibitor titer and FVIII level.

The position of imidazopyridine and metabolic activation are pivotal factors in the antimutagenic activity of novel imidazo[1,2-a]pyridine derivatives.

PubMed

El-Sayed, Wael M; Hussin, Warda A; Al-Faiyz, Yasair S; Ismail, Mohamed A

2013-09-05

The antimutagenic activity of eight novel imidazo[1,2-a]pyridine derivatives (I-VIII) against sodium azide (NaN3) and benzo[a]pyrene (B[a]P) was evaluated using the Salmonella reverse mutation assay. At non-toxic concentrations (12.5-50 µM), imidazopyridines I, II, III, and V with a terminal imidazopyridine group were mutagenic, while derivatives VII and VIII with a central imidazopyridine group were not mutagenic. Compounds IV, VII, and VIII exerted a moderate antimutagenic activity against NaN3 under pre-exposure conditions, and a strong activity (>40%) against B[a]P in the presence of S9 under both pre- and co-exposure conditions and mostly independent on the dose. Imidazopyridines possibly inhibited the microsomal-dependent activation of B[a]P. The demethylated derivative VII was the most active antimutagen. All imidazopyridines had a low to moderate antioxidant activity. The antibacterial activity of imidazopyridines was sporadic and moderate probably due to the failure of bacteria to convert imidazopyridines into active metabolites. The position of imidazopyridine was a pivotal factor in the mutagenic/antimutagenic activity. The strong antimutagenic compounds were dicationic planar compounds with a centered imidazo[1,2-a]pyridine spacer. With LD50 of 60 mg/kg in mice for both derivatives VII and VIII, it is safe to investigate the anticancer activity of these derivatives in animal models. © 2013 Elsevier B.V. All rights reserved.

Factor XI as a target for antithrombotic therapy

PubMed Central

Bane, Charles E.; Gailani, David

2014-01-01

Anticoagulants currently used in clinical practice to treat thromboembolic disorders are effective but increase the risk of severe bleeding because they target proteins that are essential for normal coagulation (hemostasis). Drugs with better safety profiles are required for prevention and treatment of thromboembolic disease. Coagulation factor XIa has emerged as a novel target for safer anticoagulant therapy because of its role in thrombosis and its relatively small contribution to hemostasis. PMID:24886766

Anticoagulation by factor Xa inhibitors.

PubMed

Orfeo, T; Butenas, S; Brummel-Ziedins, K E; Gissel, M; Mann, K G

2010-08-01

Therapeutic agents that regulate blood coagulation are critical to the management of thrombotic disorders, with the selective targeting of factor (F) Xa emerging as a promising approach. To assess anticoagulant strategies targeting FXa. A deterministic computational model of tissue factor (Tf)-initiated thrombin generation and two empirical experimental systems (a synthetic coagulation proteome reconstruction using purified proteins and a whole blood model) were used to evaluate clinically relevant examples of the two available types of FXa-directed anticoagulants [an antithrombin (AT)-dependent agent, fondaparinux, and an AT-independent inhibitor, Rivaroxaban] in experimental regimens relevant to long-term (suppression of new Tf-initiated events) and acute (suppression of ongoing coagulation processes) clinical applications. Computational representations of each anticoagulant's efficacy in suppressing thrombin generation over a range of anticoagulant concentrations in both anticoagulation regimens were validated by results from corresponding empirical reconstructions and were consistent with those recommended for long-term and acute clinical applications, respectively. All three model systems suggested that Rivaroxaban would prove more effective in the suppression of an ongoing coagulation process than fondaparinux, reflecting its much higher reactivity toward the prothrombinase complex. The success of fondaparinux in acute settings in vivo is not explained solely by its properties as an FXa inhibitor. We have reported that FIXa contributes to the long-term capacity of clot-associated catalysts to restart a coagulation process, suggesting that the enhanced anti-FIXa activity of fondaparinux-AT may be critical to its success in acute settings in vivo. © 2010 International Society on Thrombosis and Haemostasis.

Factor VIII assay

MedlinePlus

... sample from one person than another. Other slight risks from having blood drawn may include: Excessive bleeding Fainting or feeling lightheaded Hematoma (blood accumulating under the skin) Infection ( ...

An in vitro analysis of the effect of acidosis on coagulation in chronic disease states - a thromboelastograph study.

PubMed

White, Hayden; Bird, Robert; Sosnowski, Kellie; Jones, Mark

2016-06-01

Thrombosis is a complication of many chronic illnesses. Chronic obstructive pulmonary disease (COPD) and diabetes mellitus are common medical conditions frequently associated with a hypercoagulable state. Acidaemia has been shown to reduce coagulation. COPD and diabetes mellitus during acute deterioration can present with a severe acidaemia. The impact of this acidaemia on coagulation is poorly studied. Patients presenting with a diagnosis of diabetic ketoacidosis or type II respiratory failure from COPD and a pH of less than 7.2 were included in our study. A coagulation screen and a thromboelastograph (TEG) were performed on admission and 24 hours later. The mean pH on admission was 7.07 and mean base excess was -16.3. The activated partial thromboplastin time was associated with pH change but remained within the normal range (26-41 s). All other coagulation and TEG parameters failed to show evidence of association (p>0.05). In the two models of non-haemorrhagic acidosis investigated, coagulation was not altered by the changes in pH. More work is needed to understand the complex relationship between factors affecting coagulation in individual disease processes. © 2016 Royal College of Physicians.

Neonatal Plasma Transfusion: An Evidence-Based Review.

PubMed

Keir, Amy K; Stanworth, Simon J

2016-10-01

Several clinical scenarios for plasma transfusion are repeatedly identified in audits, including treatment of bleeding in association with laboratory evidence of coagulopathy, correction of disseminated intravascular coagulation, prevention of intraventricular hemorrhage, management of critically ill neonates (eg, during sepsis or as a volume expander), or correction of markers of prolonged coagulation in the absence of bleeding. The findings of at least one national audit of transfusion practice indicated that almost half of plasma transfusions are given to neonates with abnormal coagulation values with no evidence of active bleeding, despite the limited evidence base to support the effectiveness of this practice. Plasma transfusions to neonates should be considered in the clinical context of bleeding (eg, vitamin K dependent), disseminated intravascular coagulation, and very rare inherited deficiencies of coagulation factors. There seems to be no role for prophylactic plasma to prevent intraventricular hemorrhage or for use as a volume expander. Copyright © 2016 Elsevier Inc. All rights reserved.

Investigating the characteristic strength of flocs formed from crude and purified Hibiscus extracts in water treatment.

PubMed

Jones, Alfred Ndahi; Bridgeman, John

2016-10-15

The growth, breakage and re-growth of flocs formed using crude and purified seed extracts of Okra (OK), Sabdariffa (SB) and Kenaf (KE) as coagulants and coagulant aids was assessed. The results showed floc size increased from 300 μm when aluminium sulphate (AS) was used as a coagulant to between 696 μm and 722 μm with the addition of 50 mg/l of OK, KE and SB crude samples as coagulant aids. Similarly, an increase in floc size was observed when each of the purified proteins was used as coagulant aid at doses of between 0.123 and 0.74 mg/l. The largest floc sizes of 741 μm, 460 μm and 571 μm were obtained with a 0.123 mg/l dose of purified Okra protein (POP), purified Sabdariffa (PSP) and purified Kenaf (PKP) respectively. Further coagulant aid addition from 0.123 to 0.74 mg/l resulted in a decrease in floc size and strength in POP and PSP. However, an increase in floc strength and reduced d50 size was observed in PKP at a dose of 0.74 mg/l. Flocs produced when using purified and crude extract samples as coagulant aids exhibited high recovery factors and strength. However, flocs exhibited greater recovery post-breakage when the extracts were used as a primary coagulant. It was observed that the combination of purified proteins and AS improved floc size, strength and recovery factors. Therefore, the applications of Hibiscus seeds in either crude or purified form increases floc growth, strength, recoverability and can also reduce the cost associated with the import of AS in developing countries. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Rational and timely haemostatic interventions following cardiac surgery - coagulation factor concentrates or blood bank products.

PubMed

Tang, Mariann; Fenger-Eriksen, Christian; Wierup, Per; Greisen, Jacob; Ingerslev, Jørgen; Hjortdal, Vibeke; Sørensen, Benny

2017-06-01

Cardiac surgery may cause a serious coagulopathy leading to increased risk of bleeding and transfusion demands. Blood bank products are commonly first line haemostatic intervention, but has been associated with hazardous side effect. Coagulation factor concentrates may be a more efficient, predictable, and potentially a safer treatment, although prospective clinical trials are needed to further explore these hypotheses. This study investigated the haemostatic potential of ex vivo supplementation of coagulation factor concentrates versus blood bank products on blood samples drawn from patients undergoing cardiac surgery. 30 adults were prospectively enrolled (mean age=63.9, females=27%). Ex vivo haemostatic interventions (monotherapy or combinations) were performed in whole blood taken immediately after surgery and two hours postoperatively. Fresh-frozen plasma, platelets, cryoprecipitate, fibrinogen concentrate, prothrombin complex concentrate (PCC), and recombinant FVIIa (rFVIIa) were investigated. The haemostatic effect was evaluated using whole blood thromboelastometry parameters, as well as by thrombin generation. Immediately after surgery the compromised maximum clot firmness was corrected by monotherapy with fibrinogen or platelets or combination therapy with fibrinogen. At two hours postoperatively the coagulation profile was further deranged as illustrated by a prolonged clotting time, a reduced maximum velocity and further diminished maximum clot firmness. The thrombin lagtime was progressively prolonged and both peak thrombin and endogenous thrombin potential were compromised. No monotherapy effectively corrected all haemostatic abnormalities. The most effective combinations were: fibrinogen+rFVIIa or fibrinogen+PCC. Blood bank products were not as effective in the correction of the coagulopathy. Coagulation factor concentrates appear to provide a more optimal haemostasis profile following cardiac surgery compared to blood bank products. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Novel Role for Pro-Coagulant Microvesicles in the Early Host Defense against Streptococcus pyogenes

PubMed Central

Oehmcke, Sonja; Westman, Johannes; Malmström, Johan; Mörgelin, Matthias; Olin, Anders I.; Kreikemeyer, Bernd; Herwald, Heiko

2013-01-01

Previous studies have shown that stimulation of whole blood or peripheral blood mononuclear cells with bacterial virulence factors results in the sequestration of pro-coagulant microvesicles (MVs). These particles explore their clotting activity via the extrinsic and intrinsic pathway of coagulation; however, their pathophysiological role in infectious diseases remains enigmatic. Here we describe that the interaction of pro-coagulant MVs with bacteria of the species Streptococcus pyogenes is part of the early immune response to the invading pathogen. As shown by negative staining electron microscopy and clotting assays, pro-coagulant MVs bind in the presence of plasma to the bacterial surface. Fibrinogen was identified as a linker that, through binding to the M1 protein of S. pyogenes, allows the opsonization of the bacteria by MVs. Surface plasmon resonance analysis revealed a strong interaction between pro-coagulant MVs and fibrinogen with a KD value in the nanomolar range. When performing a mass-spectrometry-based strategy to determine the protein quantity, a significant up-regulation of the fibrinogen-binding integrins CD18 and CD11b on pro-coagulant MVs was recorded. Finally we show that plasma clots induced by pro-coagulant MVs are able to prevent bacterial dissemination and possess antimicrobial activity. These findings were confirmed by in vivo experiments, as local treatment with pro-coagulant MVs dampens bacterial spreading to other organs and improved survival in an invasive streptococcal mouse model of infection. Taken together, our data implicate that pro-coagulant MVs play an important role in the early response of the innate immune system in infectious diseases. PMID:23935504

Calculating inspector probability of detection using performance demonstration program pass rates

NASA Astrophysics Data System (ADS)

Cumblidge, Stephen; D'Agostino, Amy

2016-02-01

The United States Nuclear Regulatory Commission (NRC) staff has been working since the 1970's to ensure that nondestructive testing performed on nuclear power plants in the United States will provide reasonable assurance of structural integrity of the nuclear power plant components. One tool used by the NRC has been the development and implementation of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Section XI Appendix VIII[1] (Appendix VIII) blind testing requirements for ultrasonic procedures, equipment, and personnel. Some concerns have been raised, over the years, by the relatively low pass rates for the Appendix VIII qualification testing. The NRC staff has applied statistical tools and simulations to determine the expected probability of detection (POD) for ultrasonic examinations under ideal conditions based on the pass rates for the Appendix VIII qualification tests for the ultrasonic testing personnel. This work was primarily performed to answer three questions. First, given a test design and pass rate, what is the expected overall POD for inspectors? Second, can we calculate the probability of detection for flaws of different sizes using this information? Finally, if a previously qualified inspector fails a requalification test, does this call their earlier inspections into question? The calculations have shown that one can expect good performance from inspectors who have passed appendix VIII testing in a laboratory-like environment, and the requalification pass rates show that the inspectors have maintained their skills between tests. While these calculations showed that the PODs for the ultrasonic inspections are very good under laboratory conditions, the field inspections are conducted in a very different environment. The NRC staff has initiated a project to systematically analyze the human factors differences between qualification testing and field examinations. This work will be used to evaluate and prioritize potential human factors issues that may degrade performance in the field.

The fibrinogen/CRP ratio as a new parameter for the diagnosis of disseminated intravascular coagulation in patients with HELLP syndrome and as a predictive factor for neonatal outcome.

PubMed

Windsperger, Karin; Lehner, Rainer

2013-02-01

The aim of this study was to determine if the fibrinogen/C-reactive protein (CRP) ratio could be used in obstetrics as a predictor for a disseminated intravascular coagulation. One hundred eleven patients with hemolysis, elevated liver enzymes, and low platelet count syndrome at the Department of Obstetrics and Fetomaternal Medicine (General Hospital, Vienna, Austria) were selected and divided into 2 groups (overt disseminated intravascular coagulation, no overt disseminated intravascular coagulation). The classical parameters and the fibrinogen/CRP ratio were compared. The analysis was carried out using IBM SPSS statistical package (SPSS, Inc, Cary, NC). The fibrinogen/CRP ratio showed significant differences. The receiver-operating characteristic analysis showed for the ratio (area under the curve, 0.74) significantly better discriminative power than for fibrinogen (area under curve, 0.59). The odds ratio for the fibrinogen/CRP ratio was 7.04. Finally, significant correlations between the ratio and the neonatal outcome were found. We suggest the implementation of the fibrinogen/CRP ratio within patients with hemolysis, elevated liver enzymes, and low platelet count syndrome as a diagnostic and prognostic factor for the occurrence of disseminated intravascular coagulation. Copyright © 2013 Mosby, Inc. All rights reserved.

Identifying coagulopathies in the pathophysiology of cold stress syndrome in the Florida manatee Trichechus manatus latirostris.

PubMed

Barratclough, Ashley; Conner, Bobbi J; Brooks, Marjory B; Pontes Stablein, Alyssa; Gerlach, Trevor J; Reep, Roger L; Ball, Ray L; Floyd, Ruth Francis

2017-08-09

Cold stress syndrome (CSS) in the Florida manatee Trichechus manatus latirostris has been defined as morbidity and mortality resulting from prolonged exposure to water temperatures <20°C. The pathophysiology is described as multifactorial, involving nutritional, immunological and metabolic disturbances; however, the exact mechanisms are unknown. We hypothesized that thromboembolic complications contribute to the pathophysiology of CSS in addition to the previously described factors. During the winter of 2014-2015, 10 Florida manatees with clinical signs of CSS were presented to Lowry Park Zoo, Tampa, FL, USA. Thromboelastography (TEG) and coagulation panels were performed at admission. In addition, coagulation panel data from 23 retrospective CSS cases were included in the analyses. There were numerous differences between mean values of TEG and coagulation parameters for healthy manatees and those for CSS cases. Among TEG parameters, reaction time (R), clot formation time (K) and percentage of clot lysed after 30 min (LY30) values were significantly different (p < 0.05) between the 2 groups. CSS cases also had significantly higher mean D-dimer concentration and coagulation factor XI activity, prolonged mean activated partial thromboplastin time (aPTT) and significantly decreased mean antithrombin activity. These combined abnormalities include clinicopathologic criteria of disseminated intravascular coagulation, indicating an increased risk of thromboembolic disease associated with manatee CSS.

Transforming growth factor (TGF. beta. ) decreases the proliferation of human bone marrow fibroblasts by inhibiting the platelet-derived growth factor (PDGF) binding

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

Bryckaert, M.C.; Tobelem, G.; Lindroth, M.

1988-12-01

Human bone marrow fibroblasts were cultivated and characterized by immunofluorescent staining and electron microscopy. Their interactions with PDGF and TGF{beta} were studied. While a positive intracellular antifibronectin staining was observed, the cultured cells were not labeled with specific antibodies toward factor VIII von Willebrand factor (F VIII/vWF), desmin, and macrophage antigen. The binding of pure human PDGF to the cultured bone marrow fibroblasts was investigated. Addition of an excess of unlabeled PDGF decreased the binding to 75 and 80%, which means that the nonspecific binding represented 20-25% of total binding, whereas epidermal growth factor (EGF) had no effect. Two classesmore » of sites were detected by Scatchard analysis. The stimulation of DNA synthesis of PDGF was quantified by ({sup 3}H)thymidine incorporation. The results suggested that PDGF and TGF{beta} could modulate the growth of bone marrow fibroblasts.« less

A quantitative systems pharmacology model of blood coagulation network describes in vivo biomarker changes in non-bleeding subjects.

PubMed

Lee, D; Nayak, S; Martin, S W; Heatherington, A C; Vicini, P; Hua, F

2016-12-01

Essentials Baseline coagulation activity can be detected in non-bleeding state by in vivo biomarker levels. A detailed mathematical model of coagulation was developed to describe the non-bleeding state. Optimized model described in vivo biomarkers with recombinant activated factor VII treatment. Sensitivity analysis predicted prothrombin fragment 1 + 2 and D-dimer are regulated differently. Background Prothrombin fragment 1 + 2 (F 1 + 2 ), thrombin-antithrombin III complex (TAT) and D-dimer can be detected in plasma from non-bleeding hemostatically normal subjects or hemophilic patients. They are often used as safety or pharmacodynamic biomarkers for hemostatis-modulating therapies in the clinic, and provide insights into in vivo coagulation activity. Objectives To develop a quantitative systems pharmacology (QSP) model of the blood coagulation network to describe in vivo biomarkers, including F 1 + 2 , TAT, and D-dimer, under non-bleeding conditions. Methods The QSP model included intrinsic and extrinsic coagulation pathways, platelet activation state-dependent kinetics, and a two-compartment pharmacokinetics model for recombinant activated factor VII (rFVIIa). Literature data on F 1 + 2 and D-dimer at baseline and changes with rFVIIa treatment were used for parameter optimization. Multiparametric sensitivity analysis (MPSA) was used to understand key proteins that regulate F 1 + 2 , TAT and D-dimer levels. Results The model was able to describe tissue factor (TF)-dependent baseline levels of F 1 + 2 , TAT and D-dimer in a non-bleeding state, and their increases in hemostatically normal subjects and hemophilic patients treated with different doses of rFVIIa. The amount of TF required is predicted to be very low in a non-bleeding state. The model also predicts that these biomarker levels will be similar in hemostatically normal subjects and hemophilic patients. MPSA revealed that F 1 + 2 and TAT levels are highly correlated, and that D-dimer is more sensitive to the perturbation of coagulation protein concentrations. Conclusions A QSP model for non-bleeding baseline coagulation activity was established with data from clinically relevant in vivo biomarkers at baseline and changes in response to rFVIIa treatment. This model will provide future mechanistic insights into this system. © 2016 International Society on Thrombosis and Haemostasis.

Vitamin K: from coagulation to calcification.

PubMed

Paakkari, Ilari

Vitamin K is not only essential for the synthesis of coagulation factors in the liver, but it also strengthens the bones and prevents calcification of the arteries. These effects are mediated through the same mechanism, i.e. carboxylation of Gla target proteins. The discovery of novel Gla proteins that are not associated with blood coagulation or calcium metabolism indicates that vitamin K has additional effects in the pancreas and the central nervous system, for example. As dietary supplements, vitamin K1 of plant origin and vitamins K2 of bacterial origin may exert different effects.

[Thrombophilic syndrome associated to phenotypic resistance to activated protein C in postmenopausal women].

PubMed

Caserta, L; Caserta, R; Torella, M; Perricone, F; Nesti, E; Sessa, M; Tagliaferri, A; De Francesco, F; De Lucia, D; Panariello, S

2004-04-01

Hormone replacement therapy (HRT) may reduce the risk of cardiovascular events in healthy postmenopausal women. However recent studies suggest a 2-4 fold increased risk of idiopathic venous thromboembolism (VTE) among users of HRT. Our aim was to evaluate the overall effect of HRT on hemostatic variables probably related to increased VTE risk reported in epidemiological studies. Therefore, 100 healthy postmenopausal women aged 45-60 years divided into 50 HRT non-users and 50 HRT users were examined. The authors assayed on the automated coagulometer ACL7000 (Instrumentation Laboratory, Milan) the procoagulant proteins: factor VIII (VIII:C) and factor VII (VII:C); the natural anticoagulant proteins: antithrombin (ATIII), protein C (PC), protein S (PS) and the resistance to anticoagulant action of activated protein C (APC-Resistance). The free tissue factor pathway inhibitor (TFPI) was measured with an ELISA method (Diagnostica Stagò; France, Roche). The in vivo coagulation and fibrinolysis activation was evaluated by the assays of prothrombin fragment 1+2 (F1+2) and plasmin- antiplasmin complexes (PAP) using ELISA techniques. Increased levels of FVIII:C and FVII:C were observed in HRT users and HRT non-users women compared to controls (FVIII:C= 126+/-58%, 120+/-59% vs 85+/-15% p=0.0001; FVII: C 113+/-23%, 103+/-19% vs 90+/-16% p=0.0001). The activation peptides were significantly different compared to those found in control subjects; higher values were observed in HRT users compared to HRT non-users (F1+2=1.11+/-0.44 nM, 077+/-0.31 nM vs 0.45+/-0.35 p=0.00001; P-AP= 606+/-406 ng/ml, 514+/-205 ng/ml vs 235+/-59 p=0.0001). The ATIII and the PC were similar among the 3 different groups of subjects, but reduced levels of PS were observed in HRT users (PS 93+/-23%, 105+/-22% vs 109+/-12 p=0.0001). The mean normalized APC sensitivity ratio (APC-SR) was lower in the two populations of women as compared with that of controls (nAPC-SR 1.02+/-0.7, 1.02+/-0.8 vs 1.1+/-25 p=0.02). The values of free TFPI were reduced in HRT users compared to HRT non-users (9.1+/-1.9 ng/ml, 10.1+/-2.3 ng/ml vs 4.6+/-1.5 ng/ml p<0.0001). HRT appears to be associated to a shift in the procoagulant-anticoagulant balance towards a procoagulant state. The changes in hemostatic system could explain the increased risk of VTE in healthy postmenopausal women during HRT, nevertheless this risk could be higher in women known to have a congenital or acquired thrombophilic state.

Structural investigation of C4b-binding protein by molecular modeling: localization of putative binding sites.

PubMed

Villoutreix, B O; Härdig, Y; Wallqvist, A; Covell, D G; García de Frutos, P; Dahlbäck, B

1998-06-01

C4b-binding protein (C4BP) contributes to the regulation of the classical pathway of the complement system and plays an important role in blood coagulation. The main human C4BP isoform is composed of one beta-chain and seven alpha-chains essentially built from three and eight complement control protein (CCP) modules, respectively, followed by a nonrepeat carboxy-terminal region involved in polymerization of the chains. C4BP is known to interact with heparin, C4b, complement factor I, serum amyloid P component, streptococcal Arp and Sir proteins, and factor VIII/VIIIa via its alpha-chains and with protein S through its beta-chain. The principal aim of the present study was to localize regions of C4BP involved in the interaction with C4b, Arp, and heparin. For this purpose, a computer model of the 8 CCP modules of C4BP alpha-chain was constructed, taking into account data from previous electron microscopy (EM) studies. This structure was investigated in the context of known and/or new experimental data. Analysis of the alpha-chain model, together with monoclonal antibody studies and heparin binding experiments, suggests that a patch of positively charged residues, at the interface between the first and second CCP modules, plays an important role in the interaction between C4BP and C4b/Arp/Sir/heparin. Putative binding sites, secondary-structure prediction for the central core, and an overall reevaluation of the size of the C4BP molecule are also presented. An understanding of these intermolecular interactions should contribute to the rational design of potential therapeutic agents aiming at interfering specifically some of these protein-protein interactions.

Effects of dark chocolate consumption on the prothrombotic response to acute psychosocial stress in healthy men.

PubMed

von Känel, R; Meister, R E; Stutz, M; Kummer, P; Arpagaus, A; Huber, S; Ehlert, U; Wirtz, P H

2014-12-01

Flavanoid-rich dark chocolate consumption benefits cardiovascular health, but underlying mechanisms are elusive. We investigated the acute effect of dark chocolate on the reactivity of prothrombotic measures to psychosocial stress. Healthy men aged 20-50 years (mean ± SD: 35.7 ± 8.8) were assigned to a single serving of either 50 g of flavonoid-rich dark chocolate (n=31) or 50 g of optically identical flavonoid-free placebo chocolate (n=34). Two hours after chocolate consumption, both groups underwent an acute standardised psychosocial stress task combining public speaking and mental arithmetic. We determined plasma levels of four stress-responsive prothrombotic measures (i. e., fibrinogen, clotting factor VIII activity, von Willebrand Factor antigen, fibrin D-dimer) prior to chocolate consumption, immediately before and after stress, and at 10 minutes and 20 minutes after stress cessation. We also measured the flavonoid epicatechin, and the catecholamines epinephrine and norepinephrine in plasma. The dark chocolate group showed a significantly attenuated stress reactivity of the hypercoagulability marker D-dimer (F=3.87, p=0.017) relative to the placebo chocolate group. Moreover, the blunted D-dimer stress reactivity related to higher plasma levels of the flavonoid epicatechin assessed before stress (F=3.32, p = 0.031) but not to stress-induced changes in catecholamines (p's=0.35). There were no significant group differences in the other coagulation measures (p's≥0.87). Adjustments for covariates did not alter these findings. In conclusion, our findings indicate that a single consumption of flavonoid-rich dark chocolate blunted the acute prothrombotic response to psychosocial stress, thereby perhaps mitigating the risk of acute coronary syndromes triggered by emotional stress.

Impact of aerobic exercise on haemostatic indices in paediatric patients with haemophilia.

PubMed

Kumar, Riten; Bouskill, Vanessa; Schneiderman, Jane E; Pluthero, Fred G; Kahr, Walter H A; Craik, Allison; Clark, Dewi; Whitney, Karen; Zhang, Christine; Rand, Margaret L; Carcao, Manuel

2016-06-02

This study investigated the impact of aerobic exercise on laboratory assessments of haemostatic activity in boys (5-18 years of age) with haemophilia A (HA) or B (HB), examining the hypothesis that laboratory coagulation parameters temporarily improve with exercise. Thirty subjects meeting eligibility criteria (19 HA; 11 HB; mean age: 12.8 years) were invited to participate. They underwent a replacement factor washout period and were advised against strenuous activity for three days prior to the planned intervention. At study visit, baseline blood samples were drawn prior to exercise on a stationary cycle ergometer, aiming to attain 3 minutes (min) of cycling at 85 % of predicted maximum heart rate. Blood work was repeated 5 min (t5) and 60 min (t60) post exercise completion. Samples were assessed for platelet count (PC), factor VIII activity ( C), von Willebrand antigen (VWF:Ag), ristocetin cofactor activity (VWF:RCo) and platelet function analysis (PFA-100); maximum rate of thrombus generation (MRTG) in blood was measured via thromboelastography and plasma peak thrombin generation (PTG) via calibrated automated thrombography. Mean duration of exercise was 13.9 (± 2.6) min. On average, t5 samples showed significant elevation, relative to baseline in PC, FVIII:C, VWF:Ag, VWF:RCo and PTG, while C, VWF:Ag, VWF:RCo and MRTG were significantly elevated in t60 samples. Within the cohort, participants with severe HA showed no change in C levels with exercise. The greatest improvement in haemostatic indices was observed in post-adolescent males with mild-moderate HA, who thus represent the group most likely to benefit from a reduction of bleeding risk in the setting of exercise.

Use of combined coagulation-adsorption process as pretreatment of landfill leachate

PubMed Central

2013-01-01

Landfill leachate is an important pollution factor resulting from municipal landfill sites. Physical and chemical processes are the better option for pretreatment or full treatment of landfill leachate. This article presents a combination of pre-treatment method (coagulation and adsorption) for leachate collected from municipal solid waste open dumping site. Physico chemical characteristics of stabilized and fresh leachate were examined. Coagulation process was examined by using alum and ferric chloride. A low cost adsorbent, fly ash was used for adsorption studies. Coagulation studies were carried out for fresh and stabilized leachate. Adsorption studies have been conducted for alum pre-treated stabilized leachate. Effect of coagulant dose, adsorbent dose, pH and contact time were carried out. The effective optimum coagulant dosages were 0.6 g/L and 0.7 g/L for alum and ferric chloride respectively for stabilized leachate and incase of fresh leachate 0.8 g/L and 0.6 g/L for alum and ferric chloride respectively. For the alum pretreated stabilized leachate, the maximum COD removal is 28% using fly ash adsorbent with equilibrium time of 210 min and optimum dose of 6 g/L. Overall COD removal efficiency of 82% was obtained by coagulation using alum and adsorption using fly ash for stabilized leachate. The results obtained showed that combined coagulation and adsorption process can be used effectively for stabilized leachate treatment. PMID:23517661

Increased thrombin generation in a mouse model of cancer cachexia is partially interleukin-6 dependent.

PubMed

Reddel, C J; Allen, J D; Ehteda, A; Taylor, R; Chen, V M Y; Curnow, J L; Kritharides, L; Robertson, G

2017-03-01

Essentials Cancer cachexia and cancer-associated thrombosis have not previously been mechanistically linked. We assessed thrombin generation and coagulation parameters in cachectic C26 tumor-bearing mice. C26 mice are hypercoagulable, partially corrected by blocking tumor derived interleukin-6. Coagulability and anti-inflammatory interventions may be clinically important in cancer cachexia. Background Cancer cachexia and cancer-associated thrombosis are potentially fatal outcomes of advanced cancer, which have not previously been mechanistically linked. The colon 26 (C26) carcinoma is a well-established mouse model of complications of advanced cancer cachexia, partially dependent on high levels of interleukin-6 (IL-6) produced by the tumor. Objectives To assess if cancer cachexia altered the coagulation state and if this was attributable to tumor IL-6 production. Methods In male BALB/c*DBA2 (F1 hybrid) mice with a C26 tumor we used modified calibrated automated thrombogram and fibrin generation (based on overall hemostatic potential) assays to assess the functional coagulation state, and also examined fibrinogen, erythrocyte sedimentation rate (ESR), platelet count, tissue factor pathway inhibitor (TFPI) and hepatic expression of coagulation factors by microarray. C26 mice were compared with non-cachectic NC26, pair-fed and sham control mice. IL-6 expression in C26 cells was knocked down by lentiviral shRNA constructs. Results C26 mice with significant weight loss and highly elevated IL-6 had elevated thrombin generation, fibrinogen, ESR, platelets and TFPI compared with all control groups. Fibrin generation was elevated compared with pair-fed and sham controls but not compared with NC26 tumor mice. Hepatic expression of coagulation factors and fibrinolytic inhibitors was increased. Silencing IL-6 in the tumor significantly, but incompletely, attenuated the increased thrombin generation, fibrinogen and TFPI. Conclusions Cachectic C26 tumor-bearing mice are in a hypercoagulable state, which is partly attributable to IL-6 release by the tumor. The findings support the importance of the coagulation state in cancer cachexia and the clinical utility of anti-inflammatory interventions. © 2017 International Society on Thrombosis and Haemostasis.

Indirect comparisons of efficacy and weekly factor consumption during continuous prophylaxis with recombinant factor VIII Fc fusion protein and conventional recombinant factor VIII products.

PubMed

Iorio, A; Krishnan, S; Myrén, K J; Lethagen, S; McCormick, N; Yermakov, S; Karner, P

2017-05-01

Recombinant factor VIII (rFVIII) products with extended half-lives have the potential to improve adherence and outcomes in haemophilia beyond the results obtained with conventional rFVIII products. In the absence of head-to-head comparisons, annualized bleed rates (ABRs) and weekly factor consumption with rFVIII Fc fusion protein (rFVIIIFc) and conventional rFVIII products were indirectly compared using studies of continuous prophylaxis. A systematic literature review was conducted to identify studies of rFVIII products for comparison with rFVIIIFc in the continuous prophylactic treatment of previously treated adolescents and adults with moderate and severe haemophilia A. Mean ABRs were compared between rFVIIIFc and individual rFVIII studies and between rFVIIIFc and a pooled measure for rFVIII estimated by meta-analysis. Comparisons of factor consumption were based on mean or median weekly factor consumption. Results from seven studies of conventional rFVIII products (injections 2-4 times week -1 ) were compared with rFVIIIFc (injections 1.4-2.4 times week -1 ). The pooled mean ABR for rFVIII products was significantly higher compared with rFVIIIFc (difference = 2.0; P = 0.007). Compared with most rFVIII studies, the reported weekly factor consumption was lower with rFVIIIFc [mean differences = 15.5-21.8 IU kg -1 week -1 (17-26%); median differences = 12.7-29.8 IU kg -1 week -1 (16-37%)]. In one comparison, mean weekly factor consumption with rFVIII was significantly lower but mean ABR was significantly higher than rFVIIIFc. Prophylaxis with rFVIIIFc may be associated with improved bleeding rates and lower weekly factor consumption than more frequently injected rFVIII products. Relative to rFVIII products with similar bleeding rates, results indicate that rFVIIIFc is associated with reduced weekly factor consumption while requiring fewer prescribed injections. © 2017 John Wiley & Sons Ltd.

Tissue Factor Pathway Inhibitor: Multiple Anticoagulant Activities for a Single Protein.

PubMed

Mast, Alan E

2016-01-01

Tissue factor (TF) pathway inhibitor (TFPI) is an anticoagulant protein that inhibits early phases of the procoagulant response. Alternatively spliced isoforms of TFPI are differentially expressed by endothelial cells and human platelets and plasma. The TFPIβ isoform localizes to the endothelium surface where it is a potent inhibitor of TF-factor VIIa complexes that initiate blood coagulation. The TFPIα isoform is present in platelets. TFPIα contains a stretch of 9 amino acids nearly identical to those found in the B-domain of factor V that are well conserved in mammals. These amino acids provide exosite binding to activated factor V, which allows for TFPIα to inhibit prothrombinase during the initiation phase of blood coagulation. Endogenous inhibition at this point in the coagulation cascade was only recently recognized and has provided a biochemical rationale to explain the pathophysiological mechanisms underlying several clinical disorders. These include the east Texas bleeding disorder that is caused by production of an altered form of factor V with high affinity for TFPI and a paradoxical procoagulant effect of heparins. In addition, these findings have led to ideas for pharmacological targeting of TFPI that may reduce bleeding in hemophilia patients. © 2015 American Heart Association, Inc.

New associations: INFG and TGFB1 genes and the inhibitor development in severe haemophilia A.

PubMed

de Alencar, J B; Macedo, L C; de Barros, M F; Rodrigues, C; Shinzato, A H; Pelissari, C B; Machado, J; Sell, A M; Visentainer, J E L

2015-07-01

The development of factor VIII (FVIII) inhibitor is the main complication of replacement therapy in patients with haemophilia A (HA). A ratio of 5-7% of individuals HA develops antibodies (inhibitors) against the FVIII infused during the treatment, thereby reducing their pro-coagulant activity. The immunomodulatory cytokine genes have been related to the risk of development of alloantibodies in several studies, mainly in HA with severe form. We investigated the polymorphisms in regulatory regions of cytokine genes (IL1A, IL1B, IL1R, IL1RA, IL4RA, IL12, INFG, TGFB1, TNF, IL2, IL4, IL6, IL10) that could influence the risk of developing inhibitors in patients with severe HA. The genotyping of cytokine genes of 117 patients with HA was performed by polymerase chain reaction with sequence-specific primers (PCR-SSP) using the protocol recommended by the manufacturer (Invitrogen kit Cytokines(®) , Canoga Park, USA) RESULTS: From the cohort of 117 patients with severe HA, 35 developed inhibitors. There was a higher frequency of +874 T allele in INFG and of +869 TT and TG/TG in TGFB1 genes on patients with inhibitors. This suggests that polymorphisms in INFG and in TGFB1 genes are related to risk of developing inhibitor, and could contribute to a genetic profile of the individual HA for the risk of inhibitors development to FVIII. © 2015 John Wiley & Sons Ltd.

Demographic and clinical data in acquired hemophilia A: results from the European Acquired Haemophilia Registry (EACH2).

PubMed

Knoebl, P; Marco, P; Baudo, F; Collins, P; Huth-Kühne, A; Nemes, L; Pellegrini, F; Tengborn, L; Lévesque, H

2012-04-01

Acquired hemophilia A (AHA) is a rare autoimmune disease caused by autoantibodies against coagulation factor VIII and characterized by spontaneous hemorrhage in patients with no previous family or personal history of bleeding. Although data on several AHA cohorts have been collected, limited information is available on the optimal management of AHA. The European Acquired Hemophilia Registry (EACH2) was established to generate a prospective, large-scale, pan-European database on demographics, diagnosis, underlying disorders, bleeding characteristics, treatment and outcome of AHA patients. Five hundred and one (266 male, 235 female) patients from 117 centers and 13 European countries were included in the registry between 2003 and 2008. In 467 cases, hemostasis investigations and AHA diagnosis were triggered by a bleeding event. At diagnosis, patients were a median of 73.9 years. AHA was idiopathic in 51.9%; malignancy or autoimmune diseases were associated with 11.8% and 11.6% of cases. Fifty-seven per cent of the non-pregnancy-related cases were male. Four hundred and seventy-four bleeding episodes were reported at presentation, and hemostatic therapy initiated in 70.5% of patients. Delayed diagnosis significantly impacted treatment initiation in 33.5%. Four hundred and seventy-seven patients underwent immunosuppression, and 72.6% achieved complete remission. Representing the largest collection of consecutive AHA cases to date, EACH2 facilitates the analysis of a variety of open questions in AHA. © 2012 International Society on Thrombosis and Haemostasis.

Designed Ankyrin Repeat Proteins: A New Approach to Mimic Complex Antigens for Diagnostic Purposes?

PubMed Central

Hausammann, Stefanie; Vogel, Monique; Kremer Hovinga, Johanna A.; Lacroix-Desmazes, Sebastien; Stadler, Beda M.; Horn, Michael P.

2013-01-01

Inhibitory antibodies directed against coagulation factor VIII (FVIII) can be found in patients with acquired and congenital hemophilia A. Such FVIII-inhibiting antibodies are routinely detected by the functional Bethesda Assay. However, this assay has a low sensitivity and shows a high inter-laboratory variability. Another method to detect antibodies recognizing FVIII is ELISA, but this test does not allow the distinction between inhibitory and non-inhibitory antibodies. Therefore, we aimed at replacing the intricate antigen FVIII by Designed Ankyrin Repeat Proteins (DARPins) mimicking the epitopes of FVIII inhibitors. As a model we used the well-described inhibitory human monoclonal anti-FVIII antibody, Bo2C11, for the selection on DARPin libraries. Two DARPins were selected binding to the antigen-binding site of Bo2C11, which mimic thus a functional epitope on FVIII. These DARPins inhibited the binding of the antibody to its antigen and restored FVIII activity as determined in the Bethesda assay. Furthermore, the specific DARPins were able to recognize the target antibody in human plasma and could therefore be used to test for the presence of Bo2C11-like antibodies in a large set of hemophilia A patients. These data suggest, that our approach might be used to isolate epitopes from different sets of anti-FVIII antibodies in order to develop an ELISA-based screening assay allowing the distinction of inhibitory and non-inhibitory anti-FVIII antibodies according to their antibody signatures. PMID:23626669

Factor XII (Hageman factor) deficiency

MedlinePlus

... disorders: coagulation factor deficiencies. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. ... Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by ...

Sepsis-Induced Coagulation in the Baboon Lung Is Associated with Decreased Tissue Factor Pathway Inhibitor

PubMed Central

Tang, Haiwang; Ivanciu, Lacramioara; Popescu, Narcis; Peer, Glenn; Hack, Erik; Lupu, Cristina; Taylor, Fletcher B.; Lupu, Florea

2007-01-01

Increased tissue factor (TF)-dependent procoagulant activity in sepsis may be partly due to decreased expression or function of tissue factor pathway inhibitor (TFPI). To test this hypothesis, baboons were infused with live Escherichia coli and sacrificed after 2, 8, or 24 hours. Confocal and electron microscopy revealed increased leukocyte infiltration and fibrin deposition in the intravascular and interstitial compartments. Large amounts of TF were detected by immunostaining in leukocytes and platelet-rich microthrombi. TF induction was documented by quantitative reverse transcriptase-polymerase chain reaction, enzyme-linked immunosorbent assay, and coagulation assays. Lung-associated TFPI antigen and mRNA decreased during sepsis, and TFPI activity diminished abruptly at 2 hours. Blocking antibodies against TFPI increased fibrin deposition in septic baboon lungs, suggesting that TF-dependent coagulation might be aggravated by reduced endothelial TFPI. Decreased TFPI activity coincided with the release of tissue plasminogen activator and the peak of plasmin generation, suggesting that TFPI could undergo proteolytic inactivation by plasmin. Enhanced plasmin produced in septic baboons by infusion of blocking antibodies against plasminogen activator inhibitor-1 led to decreased lung-associated TFPI and unforeseen massive fibrin deposition. We conclude that activation of TF-driven coagulation not adequately countered by TFPI may underlie the widespread thrombotic complications of sepsis. PMID:17640967

Differences in coagulation among Asians and Caucasians and the implication for reconstructive microsurgery.

PubMed

Singhal, Dhruv; Smorodinsky, Emmanuil; Guo, Lifei

2011-01-01

Microvascular reconstructive surgery has seen a revival with the introduction of muscle-sparing perforator flaps. Recognition of potential ethnic differences in coagulation profiles would be important to a microvascular surgeon. Based on clinical observations, we hypothesize that Asian patients have a less thrombogenic coagulation profile than Caucasians. An extensive retrospective review was performed. The annual incidence of venous thromboembolism in the United States is generally accepted to range from 70 to 120 events per 100,000 people versus 16 to 17 events per 100,000 persons in Asia. Autopsy analysis of pulmonary embolism incidence was noted to be 15% in North Americans and less than 1% in Asian populations. Thromboelastography analysis of Asian and Caucasian patients undergoing cholecystectomy revealed different hemostatic mechanisms. Comparison of Asians and Caucasians undergoing the Fontan procedure revealed significantly lower postoperative factor levels in Asians than Caucasians. Baseline comparison of factor and serum levels revealed Asians with the least thrombogenic profiles compared with other ethnic groups. Asians and Caucasians demonstrate different baseline rates of deep vein thrombosis and pulmonary embolism, different hemostatic responses to surgery, and different baseline levels of clotting factors. Further study may lead to better pre-, intra-, and postoperative care of the free flap patient based on their ethnic coagulation profile. © Thieme Medical Publishers.

Neuro-Coagulopathy: Blood Coagulation Factors in Central Nervous System Diseases.

PubMed

De Luca, Ciro; Virtuoso, Assunta; Maggio, Nicola; Papa, Michele

2017-10-12

Blood coagulation factors and other proteins, with modulatory effects or modulated by the coagulation cascade have been reported to affect the pathophysiology of the central nervous system (CNS). The protease-activated receptors (PARs) pathway can be considered the central hub of this regulatory network, mainly through thrombin or activated protein C (aPC). These proteins, in fact, showed peculiar properties, being able to interfere with synaptic homeostasis other than coagulation itself. These specific functions modulate neuronal networks, acting both on resident (neurons, astrocytes, and microglia) as well as circulating immune system cells and the extracellular matrix. The pleiotropy of these effects is produced through different receptors, expressed in various cell types, in a dose- and time-dependent pattern. We reviewed how these pathways may be involved in neurodegenerative diseases (amyotrophic lateral sclerosis, Alzheimer's and Parkinson's diseases), multiple sclerosis, ischemic stroke and post-ischemic epilepsy, CNS cancer, addiction, and mental health. These data open up a new path for the potential therapeutic use of the agonist/antagonist of these proteins in the management of several central nervous system diseases.

Hemostatic abnormalities in Noonan syndrome.

PubMed

Artoni, Andrea; Selicorni, Angelo; Passamonti, Serena M; Lecchi, Anna; Bucciarelli, Paolo; Cerutti, Marta; Cianci, Paola; Gianniello, Francesca; Martinelli, Ida

2014-05-01

A bleeding diathesis is a common feature of Noonan syndrome, and various coagulation abnormalities have been reported. Platelet function has never been carefully investigated. The degree of bleeding diathesis in a cohort of patients with Noonan syndrome was evaluated by a validated bleeding score and investigated with coagulation and platelet function tests. If ratios of prothrombin time and/or activated partial thromboplastin time were prolonged, the activity of clotting factors was measured. Individuals with no history of bleeding formed the control group. The study population included 39 patients and 28 controls. Bleeding score was ≥2 (ie, suggestive of a moderate bleeding diathesis) in 15 patients (38.5%) and ≥4 (ie, suggestive of a severe bleeding diathesis) in 7 (17.9%). Abnormal coagulation and/or platelet function tests were found in 14 patients with bleeding score ≥2 (93.3%) but also in 21 (87.5%) of those with bleeding score <2. The prothrombin time and activated partial thromboplastin time were prolonged in 18 patients (46%) and partial deficiency of factor VII, alone or in combination with the deficiency of other vitamin K-dependent factors, was the most frequent coagulation abnormality. Moreover, platelet aggregation and secretion were reduced in 29 of 35 patients (82.9%, P < .01 for all aggregating agents). Nearly 40% of patients with the Noonan syndrome had a bleeding diathesis and >90% of them had platelet function and/or coagulation abnormalities. Results of these tests should be taken into account in the management of bleeding or invasive procedures in these patients. Copyright © 2014 by the American Academy of Pediatrics.

Reversal of dabigatran anticoagulation ex vivo: Porcine study comparing prothrombin complex concentrates and idarucizumab.

PubMed

Honickel, Markus; Treutler, Stefanie; van Ryn, Joanne; Tillmann, Sabine; Rossaint, Rolf; Grottke, Oliver

2015-04-01

Urgent surgery or life-threatening bleeding requires prompt reversal of the anticoagulant effects of dabigatran. This study assessed the ability of three- and four-factor prothrombin complex concentrate (PCC) and idarucizumab (specific antidote for dabigatran) to reverse the anticoagulant effects of dabigatran in a porcine model of trauma. Twelve animals were given dabigatran etexilate (DE) orally and dabigatran intravenously, before infliction of trauma. Six animals received tranexamic acid plus fibrinogen concentrate 12 minutes post-injury. Six PCCs (each 30 and 60 U/kg) and idarucizumab (30 and 60 mg/kg) were added to blood samples ex vivo. Coagulation was assessed by several coagulation assays. All coagulation parameters were altered after dabigatran infusion (plasma level: 442 ± 138 ng/ml). Both three- and four-factor PCCs mostly or completely reversed the effects of dabigatran on thromboelastometry variables and PT but not on aPTT. Idarucizumab neutralised plasma concentrations of dabigatran, and reversed the effects of the drug on coagulation variables. Thrombin generation showed dose-dependent over-correction following the addition of PCC, implying that elevated levels of thrombin are required to overcome dabigatran-induced coagulopathy. In contrast, treatment with idarucizumab returned thrombin generation to baseline levels. Following trauma, therapy with tranexamic acid plus fibrinogen improved correction of coagulation parameters by PCC, and thromboelastometry parameters by idarucizumab. All investigated PCCs improved dabigatran- and trauma-induced coagulopathy to a similar degree. In conclusion, this study shows that three- and four-factor PCCs are similarly effective for dabigatran reversal. Idarucizumab also reversed the effects of dabigatran and, unlike PCCs, was not associated with over-correction of thrombin generation.

12 CFR 611.1137 - Title VIII service corporations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 7 2014-01-01 2014-01-01 false Title VIII service corporations. 611.1137... Corporations § 611.1137 Title VIII service corporations. (a) What is a title VIII service corporation? A title VIII service corporation is a service corporation organized for the purpose of exercising the...

12 CFR 611.1137 - Title VIII service corporations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Title VIII service corporations. 611.1137... Organizations § 611.1137 Title VIII service corporations. (a) What is a title VIII service corporation? A title VIII service corporation is a service corporation organized for the purpose of exercising the...

12 CFR 611.1137 - Title VIII service corporations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 12 Banks and Banking 7 2012-01-01 2012-01-01 false Title VIII service corporations. 611.1137... Organizations § 611.1137 Title VIII service corporations. (a) What is a title VIII service corporation? A title VIII service corporation is a service corporation organized for the purpose of exercising the...

12 CFR 611.1137 - Title VIII service corporations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 12 Banks and Banking 7 2013-01-01 2013-01-01 false Title VIII service corporations. 611.1137... Organizations § 611.1137 Title VIII service corporations. (a) What is a title VIII service corporation? A title VIII service corporation is a service corporation organized for the purpose of exercising the...

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2014 CFR

2014-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2012 CFR

2012-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2011 CFR

2011-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

40 CFR Appendix Viii to Part 268 - LDR Effective Dates of Injected Prohibited Hazardous Wastes

Code of Federal Regulations, 2013 CFR

2013-07-01

... Prohibited Hazardous Wastes VIII Appendix VIII to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt. 268, App. VIII Appendix VIII to Part 268—LDR Effective Dates of Injected Prohibited Hazardous Wastes National Capacity LDR...

Prolonged activity of a recombinant factor VIII-Fc fusion protein in hemophilia A mice and dogs

PubMed Central

Dumont, Jennifer A.; Liu, Tongyao; Low, Susan C.; Zhang, Xin; Kamphaus, George; Sakorafas, Paul; Fraley, Cara; Drager, Douglas; Reidy, Thomas; McCue, Justin; Franck, Helen W. G.; Merricks, Elizabeth P.; Nichols, Timothy C.; Bitonti, Alan J.; Pierce, Glenn F.

2012-01-01

Despite proven benefits, prophylactic treatment for hemophilia A is hampered by the short half-life of factor VIII. A recombinant factor VIII-Fc fusion protein (rFVIIIFc) was constructed to determine the potential for reduced frequency of dosing. rFVIIIFc has an ∼ 2-fold longer half-life than rFVIII in hemophilia A (HemA) mice and dogs. The extension of rFVIIIFc half-life requires interaction of Fc with the neonatal Fc receptor (FcRn). In FcRn knockout mice, the extension of rFVIIIFc half-life is abrogated, and is restored in human FcRn transgenic mice. The Fc fusion has no impact on FVIII-specific activity. rFVIIIFc has comparable acute efficacy as rFVIII in treating tail clip injury in HemA mice, and fully corrects whole blood clotting time (WBCT) in HemA dogs immediately after dosing. Furthermore, consistent with prolonged half-life, rFVIIIFc shows 2-fold longer prophylactic efficacy in protecting HemA mice from tail vein transection bleeding induced 24-48 hours after dosing. In HemA dogs, rFVIIIFc also sustains partial correction of WBCT 1.5- to 2-fold longer than rFVIII. rFVIIIFc was well tolerated in both species. Thus, the rescue of FVIII by Fc fusion to provide prolonged protection presents a novel pathway for FVIII catabolism, and warrants further investigation. PMID:22246033

Immunosuppression for acquired hemophilia A: results from the European Acquired Haemophilia Registry (EACH2)

PubMed Central

Baudo, Francesco; Knoebl, Paul; Lévesque, Hervé; Nemes, László; Pellegrini, Fabio; Marco, Pascual; Tengborn, Lilian; Huth-Kühne, Angela

2012-01-01

Acquired hemophilia A (AHA) is an autoimmune disease caused by an autoantibody to factor VIII. Patients are at risk of severe and fatal hemorrhage until the inhibitor is eradicated, and guidelines recommend immunosuppression as soon as the diagnosis has been made. The optimal immunosuppressive regimen is unclear; therefore, data from 331 patients entered into the prospective EACH2 registry were analyzed. Steroids combined with cyclophosphamide resulted in more stable complete remission (70%), defined as inhibitor undetectable, factor VIII more than 70 IU/dL and immunosuppression stopped, than steroids alone (48%) or rituximab-based regimens (59%). Propensity score-matched analysis controlling for age, sex, factor VIII level, inhibitor titer, and underlying etiology confirmed that stable remission was more likely with steroids and cyclophosphamide than steroids alone (odds ratio = 3.25; 95% CI, 1.51-6.96; P < .003). The median time to complete remission was approximately 5 weeks for steroids with or without cyclophosphamide; rituximab-based regimens required approximately twice as long. Immunoglobulin administration did not improve outcome. Second-line therapy was successful in approximately 60% of cases that failed first-line therapy. Outcome was not affected by the choice of first-line therapy. The likelihood of achieving stable remission was not affected by underlying etiology but was influenced by the presenting inhibitor titer and FVIII level. PMID:22517903

[Case of cerebral venous thrombosis due to graves' disease with increased factor VIII activity].

PubMed

Kasuga, Kensaku; Naruse, Satoshi; Umeda, Maiko; Tanaka, Midori; Fujita, Nobuya

2006-04-01

A 39 year-old man was admitted to our hospital because of severe headache with fever continuing over two weeks. Three days after admission he developed aphasia and right hemiparesis, when his CT revealed subarachnoid hemorrhage at the left sylvian fissure. He was diagnosed as suffering from cerebral venous thrombosis because empty delta sign was positive on the enhanced brain CT. Suprasagittal sinus and bilateral transverse sinuses were not detected on the cerebral angiography. He was also diagnosed as having Graves' disease for the first time on the basis of free T3 13.56 pg/ml, free T4 4.65 ng/dl, TSH < 0.01 IU/ml, anti-TSH receptor antibody 4.3 IU/l, and thyroid stimulating antibody 224%. On the examination, homocystine and activities of antithrombin III, protein C, and protein S were normal. Antinculear, anti-DNA, anti-Sm, anticardiolipin beta2GP-I antibodies, and PR3ANCA were negative. Factor VIII activity, however, markedly increased over 300%, which has been known to increase in the cases of hyperthyroidism. He recovered well after the treatment with thiamazole in addition to warfarin followed by intravenous heparin. There are only six cases of cerebral venous thrombosis due to hyperthyroidism with increased factor VIII level. All of those cases were female, and 5 of them were taking oral contraceptives. This is a first Japanese male case.

Development of a microplate coagulation assay for Factor V in human plasma

PubMed Central

2011-01-01

Background Factor V (FV) in its activated form, FVa, is a critical regulator of thrombin generation during fibrin clot formation. There is a need of a simple, fast, and inexpensive microplate-based coagulation assay to measure the functional activity of FV in human plasma. The objective of this study was to develop a microplate-based assay that measures FV coagulation activity during clot formation in human plasma, which is currently not available. Methods The FV assay requires a kinetic microplate reader to measure the change in absorbance at 405nm during fibrin formation in human plasma. The FV assay accurately measures the time, initial rate, and extent of fibrin clot formation in human plasma. Results The FV microplate assay is simple, fast, economical, sensitive to approx 24-80pM, and multiple samples may be analyzed simultaneously. All the required materials are commercially available. Standard curves of time or initial rate of fibrin clot formation vs FV activity in the 1-stage assay (Without activation by thrombin) may be used to measure FV activity in samples of human plasma. The assay was used to demonstrate that in nine patients with disseminated intravascular coagulation (DIC), the FV 1-stage, 2-stage (With activation by thrombin), and total (2-stage activity - 1-stage activity) activities were decreased, on average, by approximately 54%, 44%, and 42%, respectively, from prolonged clot times when compared to normal pooled human reference plasma (NHP). The results indicate that the FV in the DIC patient plasmas supported both a delayed and slower rate of fibrin clot formation compared with NHP; however, the extent of fibrin clot formation in the DIC patients remained largely unchanged from that observed with NHP. Conclusions The FV microplate assay may be easily adapted to measure the activity of any coagulation factor using the appropriate factor-deficient plasma and clot initiating reagent. The microplate assay will find use in both research and clinical laboratories to provide measurement of the functional coagulation activity of FV in human plasma. PMID:21711555

Prolonged Activated Clotting Time after Protamine Administration Does Not Indicate Residual Heparinization after Cardiopulmonary Bypass in Pediatric Open Heart Surgery.

PubMed

Yamamoto, Tomohiro; Wolf, Hans-Gerd; Sinzobahamvya, Nicodème; Asfour, Boulos; Hraska, Victor; Schindler, Ehrenfried

2015-08-01

In open heart surgery, heparinization is commonly neutralized using an empirical heparin:protamine ratio ranging between 1:1 and 1:1.5. However, these ratios may result in protamine overdose that should be avoided for its negative side effects on the coagulation system. This study aimed to indicate the appropriate treatment for prolonged activated clotting time (ACT) after protamine administration following cardiopulmonary bypass (CPB) in pediatric open heart surgery by investigating the underlying reasons for it. Twenty-seven children (<10 kg) undergoing open heart surgery were included. Heparin was administered only before CPB (400 IU/kg) and in the pump priming volume for CPB (2,000 IU) and was neutralized by 1:1 protamine after CPB. The blood heparin concentration was measured using anti-Xa assay. ACT and blood concentrations of heparin, coagulation factors, thrombin-antithrombin complex, and prothrombin fragment 1 + 2 were assessed. A rotational thromboelastometry (ROTEM; Tem International GmbH, München, Bayern, Germany) was used to confirm the coagulation status and residual heparin after protamine administration. Anti-Xa assay showed that there is no residual heparin in the blood after 1:1 protamine administration. Nevertheless, ACT (128.89 ± 3.09 seconds before heparin administration) remained prolonged (177.14 ± 5.43 seconds at 10 minutes after protamine, 182.00 ± 5.90 seconds at 30 minutes after protamine). The blood concentrations of coagulation factors were significantly lower than those before heparin administration (p < 0.01). The low FIBTEM MCF of ROTEM (4.43 ± 0.32 mm) at 10 minutes after protamine indicated low fibrinogen concentration. Prolonged ACT after heparin neutralization by 1:1 protamine administration does not necessarily indicate residual heparin, but low blood concentrations of coagulation factors should be considered as a reason as well. Accordingly, supply of coagulation factors instead of additional protamine should be considered. Georg Thieme Verlag KG Stuttgart · New York.

Studies on a family with combined functional deficiencies of vitamin K-dependent coagulation factors.

PubMed Central

Goldsmith, G H; Pence, R E; Ratnoff, O D; Adelstein, D J; Furie, B

1982-01-01

Two siblings with m ild hemorrhagic symptoms had combined functional deficiencies of vitamin K-dependent clotting factors. Prothrombin (0.18-0.20 U/ml) and Stuart factor (Factor X, 0.18-0.20 U/ml) and Stuart factor (Factor X, 0.18-0.20 U/ml) were most severely affected. Antigenic amounts of affected coagulation factors were normal and normal generation of thrombin activity occurred in the patients' plasmas after treatment with nonophysiologic activators that do not require calcium for prothrombin activation. Hepatobilary disease, malabsorptive disorders, and plasma warfarin were not present. Both parents had normal levels of all coagulation factors. The patients' plasmas contained prothrombin that reacted both with antibody directed against des-gamma-carboxyprothrombin and native prothrombin. Crossed immunoelectrophoresis of patients' plasmas and studies of partially purified patient prothrombin suggested the presence of a relatively homogeneous species of dysfunctional prothrombin, distinct from the heterologous species found in the plasma of warfarin-treated persons. These studies are most consistent with a posttranslational defect in hepatic carboxylation of vitamin K-dependent factors. This kindred uniquely possesses an autosomal recessive disorder of vitamin K-dependent factor formation that causes production of an apparently homogeneous species of dysfunctional prothrombin; the functional deficiencies in clotting factors are totally corrected by oral or parenteral administration of vitamin K1. Images PMID:7085873

19 CFR Annex Viii-B to Part 351 - Schedule for Expedited Sunset Reviews

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Schedule for Expedited Sunset Reviews VIII Annex VIII-B to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-B Annex VIII-B to Part 351—Schedule for Expedited...

19 CFR Annex Viii-B to Part 351 - Schedule for Expedited Sunset Reviews

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 3 2011-04-01 2011-04-01 false Schedule for Expedited Sunset Reviews VIII Annex VIII-B to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-B Annex VIII-B to Part 351—Schedule for Expedited...

19 CFR Annex Viii-B to Part 351 - Schedule for Expedited Sunset Reviews

Code of Federal Regulations, 2013 CFR

2013-04-01

... 19 Customs Duties 3 2013-04-01 2013-04-01 false Schedule for Expedited Sunset Reviews VIII Annex VIII-B to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-B Annex VIII-B to Part 351—Schedule for Expedited...

19 CFR Annex Viii-B to Part 351 - Schedule for Expedited Sunset Reviews

Code of Federal Regulations, 2014 CFR

2014-04-01

... 19 Customs Duties 3 2014-04-01 2014-04-01 false Schedule for Expedited Sunset Reviews VIII Annex VIII-B to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-B Annex VIII-B to Part 351—Schedule for Expedited...

19 CFR Annex Viii-B to Part 351 - Schedule for Expedited Sunset Reviews

Code of Federal Regulations, 2012 CFR

2012-04-01

... 19 Customs Duties 3 2012-04-01 2012-04-01 false Schedule for Expedited Sunset Reviews VIII Annex VIII-B to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-B Annex VIII-B to Part 351—Schedule for Expedited...

42 CFR 66.206 - Grant awards.

Code of Federal Regulations, 2010 CFR

2010-10-01

... other pertinent factors: (i) The scientific, technical, or educational merit of the proposed program...; (vii) The reasonableness of the proposed budget in relation to the proposed program; and (viii) The... of such awards will be made after consideration of such factors as the grantee's progress and...

36 CFR 907.12 - Preparation of an environmental assessment.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Energy requirements and conservation; (vi) Solid waste; (vii) Transportation; (viii) Community facilities and services; (ix) Social and economic; (x) Historic and aesthetic; and (xi) Other relevant factors...

Topical application of recombinant activated factor VII during cesarean delivery for placenta previa.

PubMed

Schjoldager, Birgit T B G; Mikkelsen, Emmeli; Lykke, Malene R; Præst, Jørgen; Hvas, Anne-Mette; Heslet, Lars; Secher, Niels J; Salvig, Jannie D; Uldbjerg, Niels

2017-06-01

During cesarean delivery in patients with placenta previa, hemorrhaging after removal of the placenta is often challenging. In this condition, the extraordinarily high concentration of tissue factor at the placenta site may constitute a principle of treatment as it activates coagulation very effectively. The presumption, however, is that tissue factor is bound to activated factor VII. We hypothesized that topical application of recombinant activated factor VII at the placenta site reduces bleeding without affecting intravascular coagulation. We included 5 cases with planned cesarean delivery for placenta previa. After removal of the placenta, the surgeon applied a swab soaked in recombinant activated factor VII containing saline (1 mg in 246 mL) to the placenta site for 2 minutes; this treatment was repeated once if the bleeding did not decrease sufficiently. We documented the treatment on video recordings and measured blood loss. Furthermore, we determined hemoglobin concentration, platelet count, international normalized ratio, activated partial thrombin time, fibrinogen (functional), factor VII:clot, and thrombin generation in peripheral blood prior to and 15 minutes after removal of the placenta. We also tested these blood coagulation variables in 5 women with cesarean delivery planned for other reasons. Mann-Whitney test was used for unpaired data. In all 5 cases, the uterotomy was closed under practically dry conditions and the median blood loss was 490 (range 300-800) mL. There were no adverse effects of recombinant activated factor VII and we did not measure factor VII to enter the circulation. Neither did we observe changes in thrombin generation, fibrinogen, activated partial thrombin time, international normalized ratio, and platelet count in the peripheral circulation (all P values >.20). This study indicates that in patients with placenta previa, topical recombinant activated factor VII may diminish bleeding from the placenta site without initiation of systemic coagulation. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Effects of anti-aggregant, anti-inflammatory and anti-coagulant drug consumption on the preparation and therapeutic potential of plasma rich in growth factors (PRGF).

PubMed

Anitua, Eduardo; Troya, María; Zalduendo, Mar; Orive, Gorka

2015-02-01

The prevalence and incidence of trauma-related injuries, coronary heart disease and other chronic diseases increase dramatically with age. This population sector is therefore a regular consumer of different types of drugs that may affect platelet aggregation and the coagulation cascade. We have evaluated whether the consumption of acetylsalicylic acid, acenocoumarol, glucosamine sulfate and chondroitin sulfate, and therefore their presence in blood, could interfere with the preparation and biological outcomes of plasma rich in growth factors (PRGF). Clotting time, clot retraction and platelet activation of PRGF was evaluated. PRGF growth factor content and the release of different biomolecules by tendon fibroblasts were also quantified, as well as cell proliferation and cell migration. The preparation and biological potential of PRGF is not affected by the intake of the evaluated drugs, and solely its angiogenic potential and its capacity to induce HA and fibronectin synthesis, is reduced in patients taking anti-coagulants.

[Use of thrombelastography to guide posttraumatic hemostatic therapy: More coagulation factor concentrates and less allogenic blood transfusion?

PubMed

David, J S; Imhoff, E; Parat, S; Augey, L; Geay-Baillat, M-O; Incagnoli, P; Tazarourte, K

2016-11-01

Viscoelastic technics are used for 10 years and include the ROTEM ® and the TEG ® . These devices that exploit the viscoelastic properties of the clotting blood, allow a rapid and global analysis of the haemostatic process taking into account all the process interfering with haemostasis such as inflammation. It has been shown that the use of these technics in clinical situations such as trauma, postpartum haemorrhage, gastrointestinal bleeding or cardiac surgery may reduce the need for blood product, the cost and perhaps may improve the outcome of the patients. Thanks to a rapid identification of the underlying coagulation deficit, these technics facilitate decision-making during acute care and help to guide the treatment, particularly with coagulation factor's concentrate. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Near fatal spontaneous intraperitoneal bleeding: A rare manifestation in a congenital factor X deficiency carrier.

PubMed

Vinod, K V; Hitha, B; Kaaviya, R; Dutta, T K

2015-03-01

Congenital factor X (FX) deficiency is a rare coagulation disorder of autosomal recessive inheritance, characterized by bleeding of variable severity. Bleeding severity generally correlates with the level of FX functional activity and severe bleeding usually occurs in moderate and severe deficiency, when FX coagulant activity is <5%. FX activity above 10% is infrequently associated with severe bleeding. Here we report the rare occurrence of life-threatening massive spontaneous intraperitoneal bleeding with hypovolemic shock, resulting from spontaneous rupture of an ovarian luteal cyst in a 25-year-old FX deficiency carrier woman, with a FX activity of 26%. She was managed successfully conservatively, with fresh frozen plasma and packed red blood cell transfusions and she showed gradual improvement. The case is being reported to discuss the diagnosis and management of this rare inherited coagulation disorder.

Haemostatic monitoring during postpartum haemorrhage and implications for management

PubMed Central

Solomon, C.; Collis, R. E.; Collins, P. W.

2012-01-01

Summary Postpartum haemorrhage (PPH) is a major risk factor for maternal morbidity and mortality. PPH has numerous causative factors, which makes its occurrence and severity difficult to predict. Underlying haemostatic imbalances such as consumptive and dilutional coagulopathies may develop during PPH, and can exacerbate bleeding and lead to progression to severe PPH. Monitoring coagulation status in patients with PPH may be crucial for effective haemostatic management, goal-directed therapy, and improved outcomes. However, current PPH management guidelines do not account for the altered baseline coagulation status observed in pregnant patients, and the appropriate transfusion triggers to use in PPH are unknown, due to a lack of high-quality studies specific to this area. In this review, we consider the evidence for the use of standard laboratory-based coagulation tests and point-of-care viscoelastic coagulation monitoring in PPH. Many laboratory-based tests are unsuitable for emergency use due to their long turnaround times, so have limited value for the management of PPH. Emerging evidence suggests that viscoelastic monitoring, using thrombelastography- or thromboelastometry-based tests, may be useful for rapid assessment and for guiding haemostatic therapy during PPH. However, further studies are needed to define the ranges of reference values that should be considered ‘normal’ in this setting. Improving awareness of the correct application and interpretation of viscoelastic coagulation monitoring techniques may be critical in realizing their emergency diagnostic potential. PMID:23075633

Coagulation under flow: the influence of flow-mediated transport on the initiation and inhibition of coagulation.

PubMed

Fogelson, Aaron L; Tania, Nessy

2005-01-01

A mathematical model of intravascular coagulation is presented; it encompasses the biochemistry of the tissue factor pathway, platelet activation and deposition on the subendothelium, and flow- and diffusion-mediated transport of coagulation proteins and platelets. Simulation experiments carried out with the model indicate the predominant role played by the physical processes of platelet deposition and flow-mediated removal of enzymes in inhibiting coagulation in the vicinity of vascular injury. Sufficiently rapid production of factors IXa and Xa by the TF:VIIa complex can overcome this inhibition and lead to formation of significant amounts of the tenase complex on the surface of activated platelets and, as a consequence, to substantial thrombin production. Chemical inhibitors are seen to play almost no (TFPI) or little (AT-III and APC) role in determining whether substantial thrombin production will occur. The role of APC is limited by the necessity for diffusion of thrombin from the site of injury to nearby endothelial cells to form the thrombomodulin-thrombin complex and for diffusion in the reverse direction of the APC made by this complex. TFPI plays an insignificant part in inhibiting the TF:VIIa complex under the conditions studied whether its action involves sequential binding of TFPI to Xa and then TFPI:Xa to TF:VIIa, or direct binding of TFPI to Xa already bound to the TF:VIIa complex. Copyright 2005 S. Karger AG, Basel.

Optimum coagulant forecasting by modeling jar test experiments using ANNs

NASA Astrophysics Data System (ADS)

Haghiri, Sadaf; Daghighi, Amin; Moharramzadeh, Sina

2018-01-01

Currently, the proper utilization of water treatment plants and optimizing their use is of particular importance. Coagulation and flocculation in water treatment are the common ways through which the use of coagulants leads to instability of particles and the formation of larger and heavier particles, resulting in improvement of sedimentation and filtration processes. Determination of the optimum dose of such a coagulant is of particular significance. A high dose, in addition to adding costs, can cause the sediment to remain in the filtrate, a dangerous condition according to the standards, while a sub-adequate dose of coagulants can result in the reducing the required quality and acceptable performance of the coagulation process. Although jar tests are used for testing coagulants, such experiments face many constraints with respect to evaluating the results produced by sudden changes in input water because of their significant costs, long time requirements, and complex relationships among the many factors (turbidity, temperature, pH, alkalinity, etc.) that can influence the efficiency of coagulant and test results. Modeling can be used to overcome these limitations; in this research study, an artificial neural network (ANN) multi-layer perceptron (MLP) with one hidden layer has been used for modeling the jar test to determine the dosage level of used coagulant in water treatment processes. The data contained in this research have been obtained from the drinking water treatment plant located in Ardabil province in Iran. To evaluate the performance of the model, the mean squared error (MSE) and correlation coefficient (R2) parameters have been used. The obtained values are within an acceptable range that demonstrates the high accuracy of the models with respect to the estimation of water-quality characteristics and the optimal dosages of coagulants; so using these models will allow operators to not only reduce costs and time taken to perform experimental jar tests but also to predict a proper dosage for coagulant amounts and to project the quality of the output water under real conditions.

40 CFR Appendix Viii to Part 600 - Fuel Economy Label Formats

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Fuel Economy Label Formats VIII Appendix VIII to Part 600 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF MOTOR VEHICLES Pt. 600, App. VIII Appendix VIII to Part 600—Fuel Economy Label Formats...

19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII-A to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset...

19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

Code of Federal Regulations, 2014 CFR

2014-04-01

... 19 Customs Duties 3 2014-04-01 2014-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII-A to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset...

19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

Code of Federal Regulations, 2012 CFR

2012-04-01

... 19 Customs Duties 3 2012-04-01 2012-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII-A to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset...

19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

Code of Federal Regulations, 2013 CFR

2013-04-01

... 19 Customs Duties 3 2013-04-01 2013-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII-A to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset...

19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 3 2011-04-01 2011-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII-A to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset...

Safety and efficacy of BAY 94-9027, a prolonged-half-life factor VIII.

PubMed

Reding, M T; Ng, H J; Poulsen, L H; Eyster, M E; Pabinger, I; Shin, H-J; Walsch, R; Lederman, M; Wang, M; Hardtke, M; Michaels, L A

2017-03-01

Essentials Recombinant factor VIII BAY 94-9027 conjugates in a site-specific manner with polyethylene glycol. BAY 94-9027 was given to patients with severe hemophilia A as prophylaxis and to treat bleeds. BAY 94-9027 prevented bleeds at dose intervals up to every 7 days and effectively treated bleeds. BAY 94-9027 treatment was mainly well tolerated and no patient developed factor VIII inhibitors. Click to hear Dr Tiede's perspective on half-life extended factor VIII for the treatment of hemophilia A SUMMARY: Background BAY 94-9027 is a B-domain-deleted prolonged-half-life recombinant factor VIII (FVIII) that conjugates in a site-specific manner with polyethylene glycol. Objective Assess efficacy and safety of BAY 94-9027 for prophylaxis and treatment of bleeds in patients with severe hemophilia A. Patients/methods In this multinational, phase 2/3, partially randomized, open-label trial, men aged 12-65 years with FVIII < 1% and ≥ 150 exposure days to FVIII received BAY 94-9027 for 36 weeks on demand or prophylactically at intervals determined following a 10-week run-in period on 25 IU kg -1 body weight two times per week. Patients with > 1 bleed during the run-in subsequently received 30-40 IU kg -1 two times per week; patients with ≤ 1 bleed were eligible for randomization to every-5-days (45-60 IU kg -1 ) or every-7-days (60 IU kg -1 ) prophylaxis (1 : 1) for 26 additional weeks until randomization arms were filled. Patients who were eligible but not randomized continued twice-weekly prophylaxis. The primary efficacy outcome was annualized bleeding rate (ABR). Results The intent-to-treat population included 132 patients (prophylaxis, n = 112; on demand, n = 20). Median ABR (quartile [Q1; Q3]) for patients treated two times per week who were not eligible for randomization (n = 13) improved after dose increase (17.4 [14.3; 26.0] to 4.1 [2.0; 10.6]). Median ABR for patients randomized to every-5-days treatment (n = 43) was 1.9 (0; 4.2), similar to patients eligible for randomization but who continued treatment two times per week (n = 11). Median ABR for 32/43 patients (74%) who continued every-7-days prophylaxis until study end was 0.96 (0.0; 4.3). Six hundred and thirty-six of 702 bleeds (90.6%) were controlled with ≤ 2 infusions. No patient developed a FVIII inhibitor. Conclusions BAY 94-9027 prevented bleeding across three individually tailored dose regimens and was effective for treatment of bleeds. © 2016 The Authors. Journal of Thrombosis and Haemostasis published by Wiley Periodicals, Inc. on behalf of International Society on Thrombosis and Haemostasis.

Youth Suicidal Behavior

MedlinePlus

... ii Risk Factors* Mental illness Substance abuse iv Firearms in the household vi Previous suicide attempts viii ... connectedness iii Safe schools v Reduced access to firearms vii Academic achievement ix Self-esteem xi Talking ...

Chemical coagulation-based processes for trace organic contaminant removal: current state and future potential.

PubMed

Alexander, Jonathan T; Hai, Faisal I; Al-Aboud, Turki M

2012-11-30

Trace organic contaminants have become an increasing cause of concern for governments and water authorities as they attempt to respond to the potential challenges posed by climate change by implementing sustainable water cycle management practices. The augmentation of potable water supplies through indirect potable water reuse is one such method currently being employed. Given the uncertainty surrounding the potential human health impacts of prolonged ingestion of trace organic contaminants, it is vital that effective and sustainable treatment methods are utilized. The purpose of this article is to provide a comprehensive literature review of the performance of the chemical coagulation process in removing trace organic contaminants from water. This study evaluated the removal data collated from recent research relating to various trace organic contaminants during the coagulation process. It was observed that there is limited research data relating to the removal of trace organic contaminants using coagulation. The findings of this study suggest that there is a gap in the current research investigating the potential of new types of coagulants and exploring coagulation-based hybrid processes to remove trace organic contaminants from water. The data analysed in this study regarding removal efficiency suggests that, even for the significantly hydrophobic compounds, hydrophobicity is not the sole factor governing removal of trace organic contaminants by coagulation. This has important implications in that the usual practice of screening coagulants based on turbidity (suspended solid) removal proves inadequate in the case of trace organic contaminant removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

30 CFR 750.12 - Permit applications.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 779; (vii) Part 780; (viii) Part 783; (ix) Part 784; and (x) Part 785; (2) The following provisions of... consider the following factors as well as other relevant factors in determining the significance of a... significant deterioration limitations, or other Federal laws for air quality protection. (vii) A description...

19 CFR Annex Viii-C to Part 351 - Schedule for Full Sunset Reviews

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Schedule for Full Sunset Reviews VIII Annex VIII-C to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-C Annex VIII-C to Part 351—Schedule for Full Sunset Reviews Day 1 Event...

19 CFR Annex Viii-C to Part 351 - Schedule for Full Sunset Reviews

Code of Federal Regulations, 2014 CFR

2014-04-01

... 19 Customs Duties 3 2014-04-01 2014-04-01 false Schedule for Full Sunset Reviews VIII Annex VIII-C to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-C Annex VIII-C to Part 351—Schedule for Full Sunset Reviews Day 1 Event...

19 CFR Annex Viii-C to Part 351 - Schedule for Full Sunset Reviews

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 3 2011-04-01 2011-04-01 false Schedule for Full Sunset Reviews VIII Annex VIII-C to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-C Annex VIII-C to Part 351—Schedule for Full Sunset Reviews Day 1 Event...

19 CFR Annex Viii-C to Part 351 - Schedule for Full Sunset Reviews

Code of Federal Regulations, 2013 CFR

2013-04-01

... 19 Customs Duties 3 2013-04-01 2013-04-01 false Schedule for Full Sunset Reviews VIII Annex VIII-C to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-C Annex VIII-C to Part 351—Schedule for Full Sunset Reviews Day 1 Event...

19 CFR Annex Viii-C to Part 351 - Schedule for Full Sunset Reviews

Code of Federal Regulations, 2012 CFR

2012-04-01

... 19 Customs Duties 3 2012-04-01 2012-04-01 false Schedule for Full Sunset Reviews VIII Annex VIII-C to Part 351 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE ANTIDUMPING AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-C Annex VIII-C to Part 351—Schedule for Full Sunset Reviews Day 1 Event...

Coagulation tests show significant differences in patients with breast cancer.

PubMed

Tas, Faruk; Kilic, Leyla; Duranyildiz, Derya

2014-06-01

Activated coagulation and fibrinolytic system in cancer patients is associated with tumor stroma formation and metastasis in different cancer types. The aim of this study is to explore the correlation of blood coagulation assays for various clinicopathologic factors in breast cancer patients. A total of 123 female breast cancer patients were enrolled into the study. All the patients were treatment naïve. Pretreatment blood coagulation tests including PT, APTT, PTA, INR, D-dimer, fibrinogen levels, and platelet counts were evaluated. Median age of diagnosis was 51 years old (range 26-82). Twenty-two percent of the group consisted of metastatic breast cancer patients. The plasma level of all coagulation tests revealed statistically significant difference between patient and control group except for PT (p<0.001 for all variables except for PT; p=0.08). Elderly age (>50 years) was associated with higher D-dimer levels (p=0.003). Metastatic patients exhibited significantly higher D-dimer values when compared with early breast cancer patients (p=0.049). Advanced tumor stage (T3 and T4) was associated with higher INR (p=0.05) and lower PTA (p=0.025). In conclusion, coagulation tests show significant differences in patients with breast cancer.

Principles of dielectric blood coagulometry as a comprehensive coagulation test.

PubMed

Hayashi, Yoshihito; Brun, Marc-Aurèle; Machida, Kenzo; Nagasawa, Masayuki

2015-10-06

Dielectric blood coagulometry (DBCM) is intended to support hemostasis management by providing comprehensive information on blood coagulation from automated, time-dependent measurements of whole blood dielectric spectra. We discuss the relationship between the series of blood coagulation reactions, especially the aggregation and deformation of erythrocytes, and the dielectric response with the help of clot structure electron microscope observations. Dielectric response to the spontaneous coagulation after recalcification presented three distinct phases that correspond to (P1) rouleau formation before the onset of clotting, (P2) erythrocyte aggregation and reconstitution of aggregates accompanying early fibrin formation, and (P3) erythrocyte shape transformation and/or structure changes within aggregates after the stable fibrin network is formed and platelet contraction occurs. Disappearance of the second phase was observed upon addition of tissue factor and ellagic acid for activation of extrinsic and intrinsic pathways, respectively, which is attributable to accelerated thrombin generation. A series of control experiments revealed that the amplitude and/or quickness of dielectric response reflect platelet function, fibrin polymerization, fibrinolysis activity, and heparin activity. Therefore, DBCM sensitively measures blood coagulation via erythrocytes aggregation and shape changes and their impact on the dielectric permittivity, making possible the development of the battery of assays needed for comprehensive coagulation testing.

Intensity of factor VIII treatment and the development of inhibitors in non-severe hemophilia A patients: results of the INSIGHT case-control study.

PubMed

van Velzen, A S; Eckhardt, C L; Peters, M; Leebeek, F W G; Escuriola-Ettingshausen, C; Hermans, C; Keenan, R; Astermark, J; Male, C; Peerlinck, K; le Cessie, S; van der Bom, J G; Fijnvandraat, K

2017-07-01

Essentials Research suggests that intensive treatment episodes may increase the risk to develop inhibitors. We performed an international nested case-control study with 298 non-severe hemophilia A patients. Surgery and a high dose of factor VIII concentrate were associated with increased inhibitor risk. Physicians need to review arguments for factor VIII dose and elective surgery extra critically. Background Inhibitor development is a major complication of treatment with factor VIII concentrates in hemophilia. Findings from studies among severe hemophilia A patients suggest that intensive treatment episodes increase the risk of developing inhibitors. Objectives We set out to assess whether intensive treatment is also associated with an increased risk of inhibitor development among non-severe hemophilia A patients. Patients/Methods We performed a nested case-control study. A total of 75 inhibitor patients (cases) and 223 control patients were selected from 2709 non-severe hemophilia A patients (FVIII:C, 2-40%) of the INSIGHT cohort study. Cases and controls were matched for date of birth and cumulative number of exposure days (EDs) to FVIII concentrates. Conditional logistic regression was used to calculate both unadjusted and adjusted odds ratios (aOR); the latter were adjusted for a priori specified confounders. Results Peak treatment of 5 or 10 consecutive EDs did not increase inhibitor risk (aOR, 1.0; 95% confidence interval (CI), 0.4-2.5; and aOR, 1.8; CI, 0.6-5.5, respectively). Both surgical intervention (aOR, 4.2; CI, 1.7-10.3) and a high mean dose (> 45 IU kg -1 /ED) of FVIII concentrate (aOR, 7.5; CI, 1.6-35.6) were associated with an increased inhibitor risk. Conclusions Our findings suggest that high-dose FVIII treatment and surgery increase the risk of inhibitor development in non-severe hemophilia A. Together with the notion that non-severe hemophilia A patients are at a lifelong risk of inhibitor development, we suggest that in the future physicians will review the arguments for the FVIII dose and elective surgery extra critically. © 2017 International Society on Thrombosis and Haemostasis.

Imaging analyses of coagulation-dependent initiation of fibrinolysis on activated platelets and its modification by thrombin-activatable fibrinolysis inhibitor.

PubMed

Brzoska, Tomasz; Suzuki, Yuko; Sano, Hideto; Suzuki, Seiichirou; Tomczyk, Martyna; Tanaka, Hiroki; Urano, Tetsumei

2017-04-03

Using intravital confocal microscopy, we observed previously that the process of platelet phosphatidylserine (PS) exposure, fibrin formation and lysine binding site-dependent plasminogen (plg) accumulation took place only in the centre of thrombi, not at their periphery. These findings prompted us to analyse the spatiotemporal regulatory mechanisms underlying coagulation and fibrinolysis. We analysed the fibrin network formation and the subsequent lysis in an in vitro experiment using diluted platelet-rich plasma supplemented with fluorescently labelled coagulation and fibrinolytic factors, using confocal laser scanning microscopy. The structure of the fibrin network formed by supplemented tissue factor was uneven and denser at the sites of coagulation initiation regions (CIRs) on PS-exposed platelets. When tissue-type plasminogen activator (tPA; 7.5 nM) was supplemented, labelled plg (50 nM) as well as tPA accumulated at CIRs, from where fibrinolysis started and gradually expanded to the peripheries. The lysis time at CIRs and their peripheries (50 µm from the CIR) were 27.9 ± 6.6 and 44.4 ± 9.7 minutes (mean ± SD, n=50 from five independent experiments) after the addition of tissue factor, respectively. Recombinant human soluble thrombomodulin (TMα; 2.0 nM) attenuated the CIR-dependent plg accumulation and strongly delayed fibrinolysis at CIRs. A carboxypeptidase inhibitor dose-dependently enhanced the CIR-dependent fibrinolysis initiation, and at 20 µM it completely abrogated the TMα-induced delay of fibrinolysis. Our findings are the first to directly present crosstalk between coagulation and fibrinolysis, which takes place on activated platelets' surface and is further controlled by thrombin-activatable fibrinolysis inhibitor (TAFI).

Hemostasis biomarkers and incident cognitive impairment: the REGARDS study.

PubMed

Gillett, S R; McClure, L A; Callas, P W; Thacker, E L; Unverzagt, F W; Wadley, V G; Letter, A J; Cushman, M

2018-05-07

Vascular risk factors are associated with cognitive impairment, a condition with substantial public health burden. We hypothesized that hemostasis biomarkers related to vascular disease would be associated with risk of incident cognitive impairment. We performed a nested case control study including 1,082 participants with 3.5 years of follow-up in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a longitudinal cohort study of 30,239 black and white Americans ≥45 years old. Participants were free of stroke or cognitive impairment at baseline. Baseline D-dimer, fibrinogen, factor VIII, and protein C were measured in 495 cases who developed cognitive impairment during follow-up (based on abnormal scores on ≥2 of 3 cognitive tests) and 587 controls. Unadjusted ORs for incident cognitive impairment were 1.32 (95% CI 1.02, 1.70) for D-dimer >0.50 μg/mL, 1.83 (CI 1.24, 2.71) for fibrinogen >90 th percentile, 1.63 (CI 1.11, 2.38) for factor VIII >90 th percentile and 1.10 (CI 0.73, 1.65) for protein C < 10 th percentile. There were no differences in associations by race or region. Adjustment for demographic, vascular and health behavior risk factors attenuated these associations. However, having at least 2 elevated biomarkers was associated with incident cognitive impairment, with an adjusted OR 1.73 (CI 1.10, 2.69). Elevated D-dimer, fibrinogen, and factor VIII were not associated with occurrence of cognitive impairment after multivariable adjustment; however, having at least 2 abnormal biomarkers was associated, suggesting the burden of these biomarkers is relevant. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Factor II deficiency

MedlinePlus

... disorders: coagulation factor deficiencies. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. ... Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by ...

Factor X deficiency

MedlinePlus

... disorders: coagulation factor deficiencies. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. ... Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by ...

Factor VII deficiency

MedlinePlus

... disorders: coagulation factor deficiencies. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. ... Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by ...

TREATMENT OF LANDFILL LEACHATE BY COUPLING COAGULATION-FLOCCULATION OR OZONATION TO GRANULAR ACTIVATED CARBON ADSORPTION.

PubMed

Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim; Demeestere, Kristof; Van Hulle, Stijn W H

2015-01-01

A major concern for landfilling facilities is the treatment of their leachate. To optimize organic matter removal from this leachate, the combination of two or more techniques is preferred in order to meet stringent effluent standards. In our study, coagulation-flocculation and ozonation are compared as pre- treatment steps for stabilized landfill leachate prior to granular activated carbon (GAC) adsorption. The efficiency of the pre treatment techniques is evaluated using COD and UVA254 measurements. For coagulation- flocculation, different chemicals are compared and optimal dosages are determined. After this, iron (III) chloride is selected for subsequent adsorption studies due to its high percentage of COD and UVA254 removal and good sludge settle-ability. Our finding show that ozonation as a single treatment is effective in reducing COD in landfill leachate by 66% compared to coagulation flocculation (33%). Meanwhile, coagulation performs better in UVA254 reduction than ozonation. Subsequent GAC adsorption of ozonated effluent, coagulated effluent and untreated leachate resulted in 77%, 53% and 8% total COD removal respectively (after 6 bed volumes). The effect of the pre-treatment techniques on GAC adsorption properties is evaluated experimentally and mathematically using Thomas and Yoon-Nelson models. Mathematical modelling of the experimental GAC adsorption data shows that ozonation increases the adsorption capacity and break through time with a factor of 2.5 compared to coagulation-flocculation.

Stability of colloidal gold and determination of the Hamaker constant

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

Demirci, S.; Enuestuen, B.V.; Turkevich, J.

1978-12-14

Previous computation of stability factors of colloidal gold from coagulation data was found to be in systematic error due to an underestimation of the particle concentration by electron microscopy. A new experimental technique was developed for determination of this concentration. Stability factors were recalculated from the previous data using the correct concentration. While most of the previously reported conclusions remain unchanged, the absolute rate of fast coagulation is found to agree with that predicted by the theory. A value of the Hamaker constant was determined from the corrected data.

6-Methylsulfinylhexyl isothiocyanate modulates endothelial cell function and suppresses leukocyte adhesion.

PubMed

Okamoto, Takayuki; Akita, Nobuyuki; Nagai, Masashi; Hayashi, Tatsuya; Suzuki, Koji

2014-01-01

6-Methylsulfinylhexyl isothiocyanate (6-MSITC) is an active compound in wasabi (Wasabia japonica Matsum.), which is one of the most popular spices in Japan. 6-MSITC suppresses lipopolysaccharide-induced macrophage activation, arachidonic- or adenosine diphosphate-induced platelet activation, and tumor cell proliferation. These data indicate that 6-MSITC has several biological activities involving anti-inflammatory, anti-coagulant, and anti-apoptosis properties. Endothelial cells (ECs) maintain vascular homeostasis and play crucial roles in crosstalk between blood coagulation and vascular inflammation. In this study, we determined the anti-coagulant and anti-inflammatory effects of 6-MSITC on human umbilical vein endothelial cells (HUVECs). 6-MSITC slightly reduced tissue factor expression, but did not alter von Willebrand factor release in activated HUVECs. 6-MSITC modulated the generation of activated protein C, which is essential for negative regulation of blood coagulation, on normal ECs. In addition, 6-MSITC reduced tumor necrosis factor-α (TNF-α)-induced interleukin-6 and monocyte chemoattractant protein-1 expression. 6-MSITC markedly attenuated TNF-α-induced adhesion of human monoblast U937 cells to HUVECs and reduced vascular cell adhesion molecule-1 and E-selectin mRNA expression in activated ECs. These results showed that 6-MSITC modulates EC function and suppresses cell adhesion. This study provides new insight into the mechanism of the anti-inflammatory effect of 6-MSITC, suggesting that 6-MSITC has therapeutic potential as a treatment for vasculitis and vascular inflammation.

IgMk paraprotein from gammopathy patient can bind to cardiolipin and interfere with coagulation assay: a case report.

PubMed

Wu, Xin-Yao; Yin, Yu-Feng; Teng, Jia-Lin; Zhang, Li-Wei; Yang, Cheng-de

2017-06-23

The monoclonal gammopathies are a group of plasma-cell proliferative disorders characterized by the secretion of monoclonal immunoglobulin (M protein or paraprotein). Some rare cases have revealed the specific affinity of paraprotein as autoantibody. Here we report a patient with monoclonal gammopathy of undetermined significance (MGUS) accompanied by a remarkable increase of anticardiolipin antibody (aCL) and an extensively decreased coagulation factor activity, however, without any clinical signs of antiphospholipid syndrome (APS) and bleeding. Our further investigation indicated that IgMκ paraprotein of this patient possessed an antibody activity against phospholipids so as to bind to cardiolipin and interfere with coagulation assay in vitro. This case might be indicative that an abnormality of coagulation tests, disturbed by IgMκ paraprotein, does not predict a risk of bleeding in this patient.

Antithrombin, an Important Inhibitor in Blood Clots.

PubMed

Zhu, Ying; Cong, Qing-Wei; Liu, Yue; Wan, Chun-Ling; Yu, Tao; He, Guang; He, Lin; Cai, Lei; Chou, Kuo-Chen

2016-01-01

Blood coagulation is healthy and lifesaving because it can stop bleeding. It can, however, be a troublemaker as well, causing serious medical problems including heart attack and stroke. Body has complex blood coagulation cascade to modulate the blood clots. In the environment of plasma, the blood coagulation cascade is regulated by antithrombin, which is deemed one of the most important serine protease inhibitors. It inhibits thrombin; it can inhibit factors IXa and Xa as well. Interestingly, its inhibitory ability will be significantly increased with the existence of heparin. In this minireview paper, we are to summarize the structural features of antithrombin, as well as its heparin binding modes and anti-coagulation mechanisms, in hopes that the discussion and analysis presented in this paper can stimulate new strategies to find more effective approaches or compounds to modulate the antithrombin.

Principal component analysis to assess the efficiency and mechanism for enhanced coagulation of natural algae-laden water using a novel dual coagulant system.

PubMed

Ou, Hua-Se; Wei, Chao-Hai; Deng, Yang; Gao, Nai-Yun; Ren, Yuan; Hu, Yun

2014-02-01

A novel dual coagulant system of polyaluminum chloride sulfate (PACS) and polydiallyldimethylammonium chloride (PDADMAC) was used to treat natural algae-laden water from Meiliang Gulf, Lake Taihu. PACS (Aln(OH)mCl3n-m-2k(SO4)k) has a mass ratio of 10 %, a SO4 (2-)/Al3 (+) mole ratio of 0.0664, and an OH/Al mole ratio of 2. The PDADMAC ([C8H16NCl]m) has a MW which ranges from 5 × 10(5) to 20 × 10(5) Da. The variations of contaminants in water samples during treatments were estimated in the form of principal component analysis (PCA) factor scores and conventional variables (turbidity, DOC, etc.). Parallel factor analysis determined four chromophoric dissolved organic matters (CDOM) components, and PCA identified four integrated principle factors. PCA factor 1 had significant correlations with chlorophyll-a (r=0.718), protein-like CDOM C1 (0.689), and C2 (0.756). Factor 2 correlated with UV254 (0.672), humic-like CDOM component C3 (0.716), and C4 (0.758). Factors 3 and 4 had correlations with NH3-N (0.748) and T-P (0.769), respectively. The variations of PCA factors scores revealed that PACS contributed less aluminum dissolution than PAC to obtain equivalent removal efficiency of contaminants. This might be due to the high cationic charge and pre-hydrolyzation of PACS. Compared with PACS coagulation (20 mg L(-1)), the removal of PCA factors 1, 2, and 4 increased 45, 33, and 12 %, respectively, in combined PACS-PDADMAC treatment (0.8 mg L(-1) +20 mg L(-1)). Since PAC contained more Al (0.053 g/1 g) than PACS (0.028 g/1 g), the results indicated that PACS contributed less Al dissolution into the water to obtain equivalent removal efficiency.

Current options and new developments in the treatment of haemophilia.

PubMed

Wong, Trisha; Recht, Michael

2011-02-12

Haemophilia A and B are X-linked bleeding disorders due to the inherited deficiency of factor VIII or factor IX, respectively. Of the approximately 1 per 5000-10000 male births affected by haemophilia, 80% are deficient in factor VIII and 20% are deficient in factor IX. Haemophilia is characterized by spontaneous and provoked joint, muscle, gastrointestinal and CNS bleeding leading to major morbidity and even mortality if left untreated or under-treated. The evolution of haemophilia management has been marked by tragedy and triumph over recent decades. Clotting factors and replacement strategies continue to evolve for patients without inhibitors. For patients with an inhibitor, factor replacement for acute bleeding episodes and immune tolerance, immune modulation and extracorporeal methods for inhibitor reduction are the cornerstone of care. In addition, adjuvant therapies such as desmopressin, antifibrinolytics and topical agents also contribute to improved outcomes for patients with and without inhibitors. The future direction of haemophilia care is promising with new longer-acting clotting factors and genetic therapies, including gene transfer and premature termination codon suppressors. With these current and future treatment modalities, the morbidity and mortality rates in patients with haemophilia certainly will continue to improve.

Factor Xa Activation of Factor V is of Paramount Importance in Initiating the Coagulation System: Lessons from a Tick Salivary Protein

PubMed Central

Schuijt, Tim J.; Bakhtiari, Kamran; Daffre, Sirlei; DePonte, Kathleen; Wielders, Simone J.H.; Marquart, J. Arnoud; Hovius, Joppe W.; van der Poll, Tom; Fikrig, Erol; Bunce, Matthew W.; Camire, Rodney M.; Nicolaes, Gerry A.F.; Meijers, Joost C.M.; van 't Veer, Cornelis

2013-01-01

Background Generation of active procoagulant cofactor FVa and its subsequent association with the enzyme FXa to form the prothrombinase complex is a pivotal initial event in blood coagulation and has been the subject of investigative effort, speculation and controversy. The current paradigm assumes that FV activation is initiated by limited proteolysis by traces of (meizo) thrombin. Methods and Results Recombinant tick salivary protein TIX-5 was produced and anticoagulant properties were studied using plasma, whole blood and purified systems. Here we report that TIX-5 specifically inhibits FXa-mediated FV activation involving the B-domain of FV and show that FXa activation of FV is pivotal for plasma and blood clotting. In line, tick feeding is impaired on TIX-5 immune rabbits displaying the in vivo importance of TIX-5. Conclusions Our data elucidate a unique molecular mechanism by which ticks inhibit the host's coagulation system. Based on our data we propose a revised blood coagulation scheme wherein direct FXa-mediated FV activation occurs in the initiation phase during which thrombin-mediated FV activation is restrained by fibrinogen and inhibitors. PMID:23817575

Polyacrylamide grafted cellulose as an eco-friendly flocculant: Key factors optimization of flocculation to surfactant effluent.

PubMed

Zhu, Hangcheng; Zhang, Yong; Yang, Xiaogang; Shao, Lan; Zhang, Xiumei; Yao, Juming

2016-01-01

The discharge of effluents from surfactant manufacturers is giving rise to increasingly serious environmental problems. In order to develop the eco-friendly flocculation materials to achieve effective removal of pollutants from the surfactant effluents, the bamboo pulp cellulose from Phyllostachys heterocycla is employed as the skeleton material to synthesize an eco-friendly bamboo pulp cellulose-g-polyacrylamide (BPC-g-PAM) for flocculation. The BPC-g-PAM is used with the metal ions as the coagulant to treat the effluent from a surfactant manufacturer. The response surface methodology coupled with Box-behnken design is employed to optimize the key factors of coagulation-flocculation. The results show that the combination of Fe(3+) with BPC-g-PAM achieves the best coagulation-flocculation performance like, the fast treatment time, minimum coagulant and BPC-g-PAM dosages compared with the other two combinations of Al(3+) with BPC-g-PAM and Ca(2+) with BPC-g-PAM. Therefore, the combination of Fe(3+) with BPC-g-PAM is expected to promote its application for the pollution control in the surfactant manufacturers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hyper-coagulable profile with elevated pro-thrombotic biomarkers and increased cerebro- and cardio-vascular disease risk exist among healthy dyslipidemic women.

PubMed

Ferreira, Cláudia N; Carvalho, Maria G; Reis, Helton J; Gomes, Karina B; Sousa, Marinez O; Palotás, András

2014-05-01

Dyslipidemia is one of the pathognomonic elements of athero-genesis, as well as cerebro- and cardio-vascular disease (CCVD). Hemostatic factors are also involved in athero-sclerosis and ischemic changes, however their relationship with disrupted lipid homeostasis is not well characterized. The aim of this study was to determine the coagulation state of dyslipidemic patients and to evaluate their association with CCVD risk factors. Biochemical and hematological parameters, as well as neuro-psychiatric profile of 109 dyslipidemic subjects and 107 normo-lipidic healthy volunteers were assessed. Serum bio-marker levels and cognitive performance generally did not differ in the groups, but prothrombin fragment 1+2 (F1+2) and D-dimer concentrations were markedly higher among women. Hyper-coagulability was not associated with dyslipidemia, but was correlated with the female gender, which might pose an increased thromboembolic risk in asymptomatic women.

40 CFR 60.2635 - What are the operator training and qualification requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Combustion controls and monitoring. (v) Operation of air pollution control equipment and factors affecting... devices. (vii) Actions to correct malfunctions or conditions that may lead to malfunction. (viii) Bottom...

Metabolic aspects and viability of heparin/CPDA-1-stored red cell concentrate as a by-product of a high-yield factor VIII production method.

PubMed

de Jonge, J; Smit Sibinga, C T; Das, P C

1983-01-01

As a by-product of a new high-yield method of production of freeze-dried factor VIII, red cell concentrate (RCC) containing a small amount of heparin besides CPDA-1 was studied. Compared to CPDA-1 stored RCC no difference was found in hematology parameters and 2,3-DPG levels during 28 days storage. Although still in the normal range for transfusion, ATP levels were significantly lower compared to CPDA-1-stored RCC after 30 days shelf life. A survival study with 51Cr-labelled red cells showed good recovery and normal red cell half-life. Rapid transfusion of heparin/CPDA-1 RCC in 6 volunteers did not have any effect on aPTT. Heparin could not be detected in posttransfusion plasma samples.

Hemostatic Abnormalities in Multiple Myeloma Patients

PubMed Central

Gogia, Aarti; Sikka, Meera; Sharma, Satender; Rusia, Usha

2018-01-01

Background: Multiple myeloma (MM) is a neoplastic plasma cell disorder characterized by clonal proliferation of plasma cells in the bone marrow. Diverse hemostatic abnormalities have been reported in patients with myeloma which predispose to bleeding and also thrombosis. Methods: Complete blood count, biochemical parameters and parameters of hemostasis i.e. platelet count, prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), factor VIII assay results, plasma fibrinogen, D-dimer and lupus anticoagulant, were assessed in 29 MM patients and 30 age matched controls. Results: The most frequent abnormal screening parameter was APTT. Of the six indicative of a bleeding tendency i.e. thrombocytopenia, prolonged PT, APTT, TT, reduced plasma fibrinogen and factor VIII, at least one was abnormal in 8 (27.6%) patients. Of the four prothrombotic markers, lupus anticoagulant, D-dimer, elevated factor VIII and plasma fibrinogen, one or more marker was present in 24 (82.7%). D-dimer was the most common prothrombotic marker, being elevated in 22 (75.9%) patients. One or more laboratory parameter of hemostasis was abnormal in all 29 (100%) patients. Though thrombotic complications are reported to be less frequent as compared to hemorrhagic manifestations, one or more marker of thrombosis was present in 24 (82.7%) patients. Conclusion: This study provided laboratory evidence of hemostatic dysfunction which may be associated with thrombotic or bleeding complications at diagnosis in all MM patients. Hence, screening for these abnormalities at the time of diagnosis should help improved prognosis in such cases. PMID:29373903

Neovascularization of the corpus luteum of rats during the estrus cycle.

PubMed

Tsukada, K; Matsushima, T; Yamanaka, N

1996-06-01

In order to elucidate the chronological morphological changes of the corpus luteum (CL) of rats, as a physiological angiogenesis model, the CL of rat ovaries was studied light microscopically using periodic acid methenamine silver staining (PAM) and immunostaining for type IV collagen, laminin, thrombomodulin (TM), factor VIII related antigen (factor VIII) and alpha-smooth muscle actin (alpha-SMA). The CL was also studied electron microscopically. Female Wistar-Imamichi rats were used, which have a regular 4-day estrous cycle. The histological changes of the CL were observed in 6-hour intervals from 4 h before the ovulation to 28 h post-ovulation during the estrous cycle. Once the basement membrane (BM) of the follicle disintegrated following ovulation, developing capillaries entered into the CL and formed a vascular lumen with a surrounding BM, which showed positive for PAM staining, type IV collagen and laminin. The developing capillaries in the CL showed a weakly positive reaction for TM and factor VIII, but were negative for alpha-SMA. However, the appearance of immature pericytes around the well-developed capillary was obvious with electron microscopy. The study reported here provides detailed descriptions of angiogenesis during luteinization. It is concluded that the angiogenesis of the CL begins at the time of destruction of the BM of the ovarian follicle, and that the capillary BM appears when the capillary forms its lumen. Moreover, it was demonstrated that the capillary does not develop into an arteriole during luteinization.

Coagulation is more affected by quick than slow bleeding in patients with massive blood loss.

PubMed

Zhao, Juan; Yang, Dejuan; Zheng, Dongyou

2017-03-01

Profuse blood loss affects blood coagulation to various degrees. However, whether bleeding speed affects coagulation remains uncertain. This study aimed to evaluate the effect of bleeding speed on coagulation function. A total of 141 patients in the Department of Thoracic Surgery of our hospital were evaluated between January 2007 and February 2014. There are two groups of patients, those who received decortication for chronic encapsulated empyema were called the slow-bleeding group, and those who received thoracoscopic upper lobectomy were called the fast bleeding group; each group was further subdivided into three: group A, 1000 ml ≤ bleeding amount < 1500 ml; group B, 1500 ml ≤ bleeding amount < 1700 ml; group C, 1700 ml ≤ bleeding amount < 2000 ml. Then, coagulation function was assessed in all patients before and during surgery and at 1, 2, and 24 h after surgery, measuring prothrombin time, activated partial thromboplastin time (APTT), fibrinogen, blood pressure, hematocrit, hemoglobin, and platelets. Bleeding duration was overtly longer in the slow-bleeding group than that in quick bleeding individuals (2.3 ± 0.25 h vs. 0.41 ± 0.13 h, P < 0.001). Fibrinogen, hematocrit, hemoglobin, and platelets strikingly decreased, whereas prothrombin time and APTT values significantly increased with bleeding amounts in both quick and slow-bleeding groups. Interestingly, compared with slow-bleeding patients, coagulation indices at each time point and bleeding amounts had significant differences in the quick bleeding group.Increased consumption of coagulation factors in quick bleeding may have greater impact on coagulation function.

Effects of Recombinant Activated Factor VII in Traumatic Nonsurgical Intracranial Hemorrhage

DTIC Science & Technology

2006-09-01

with inhibitors to factors VIII and IX, and it is ap- proved in Europe for the treatment of patients with acquired hemophilia, congenital FVII deficiency...GARY P. WRATTEN SURGICAL SYMPOSIUM Effects of Recombinant Activated Factor VII in Traumatic Nonsurgical Intracranial Hemorrhage Christopher E. White...OBJECTIVE: To determine whether treatment with recombi- nant activated factor VII (rFVIIa) will prevent progression of bleeding in nonsurgical

[Reference values for the blood coagulation tests in Mexico: usefulness of the pooled plasma from blood donors].

PubMed

Calzada-Contreras, Adriana; Moreno-Hernández, Manuel; Castillo-Torres, Noemi Patricia; Souto-Rosillo, Guadalupe; Hernández-Juárez, Jesús; Ricardo-Moreno, María Tania; Sánchez-Fernández, Maria Guadalupe de Jesús; García-González, América; Majluf-Cruz, Abraham

2012-01-01

The blood coagulation system maintains the blood in a liquid state and bleeding and thrombosis are the manifestations of its malfunction. Blood coagulation laboratory evaluates the physiology of this system. To establish both, the reference values for several tests performed at the blood coagulation laboratory as well as the utility of the pooled plasma to perform these assays. MATERIAL AND: In this descriptive, cross-sectional, randomized study, we collected plasma from Mexican Mestizos. Each pooled plasma was prepared with the plasma from at least 20 blood donors. We performed screening and special tests and the Levey-Jennings graphs were built and interpreted after each pass. Results of the tests were analyzed and their distribution was established using the Kolmogorov-Smirnov test. To establish the reference values we used 95% confidence intervals. We collected 72 pooled plasmas. The distribution for PT, APTT, and TT tests was abnormal. Although the PT test showed a bimodal distribution it was normal for factor VII. The reference values for the hemostatic, anticoagulant, and fibrinolytic factors were different from those suggested by the manufacturers. We established the reference values for the blood coagulation tests in the adult Mexican population. We have shown that the pooled plasma must be used for the screening tests. We suggest that each clinical laboratory should establish its own reference values (at least for the screening tests). To reach this objective, we encourage the use of the pooled plasma.

Activation of Blood Coagulation in Two Prototypic Autoimmune Skin Diseases: A Possible Link with Thrombotic Risk.

PubMed

Cugno, Massimo; Tedeschi, Alberto; Borghi, Alessandro; Bucciarelli, Paolo; Asero, Riccardo; Venegoni, Luigia; Griffini, Samantha; Grovetti, Elena; Berti, Emilio; Marzano, Angelo Valerio

2015-01-01

Coagulation activation has been demonstrated in two prototypic autoimmune skin diseases, chronic autoimmune urticaria and bullous pemphigoid, but only the latter is associated with increased thrombotic risk. Two markers of coagulation activation (prothrombin fragment F1+2 and fibrin fragment D-dimer) were measured by immunoenzymatic methods in plasma samples from 30 patients with active chronic autoimmune urticaria, positive for autologous serum skin test, 30 patients with active bullous pemphigoid and 30 healthy subjects. In skin biopsies, tissue factor expression was evaluated by both immunohistochemistry and in situ hybridization. F1+2 and D-dimer levels were higher in active chronic autoimmune urticaria (276.5±89.8 pmol/L and 5.56±4.40 nmol/L, respectively) than in controls (145.2±38.0 pmol/L and 1.06±0.25 nmol/L; P=0.029 and P=0.011) and were much higher in active bullous pemphigoid (691.7±318.7 pmol/L and 15.24±9.09 nmol/L, respectively) (P<0.0001). Tissue factor positivity was evident in skin biopsies of both disorders with higher intensity in bullous pemphigoid. F1+2 and D-dimer, during remission, were markedly reduced in both disorders. These findings support the involvement of coagulation activation in the pathophysiology of both diseases. The strong systemic activation of coagulation in bullous pemphigoid may contribute to increase the thrombotic risk and provides the rationale for clinical trials on anticoagulant treatments in this disease.

Activation of Blood Coagulation in Two Prototypic Autoimmune Skin Diseases: A Possible Link with Thrombotic Risk

PubMed Central

Cugno, Massimo; Tedeschi, Alberto; Borghi, Alessandro; Bucciarelli, Paolo; Asero, Riccardo; Venegoni, Luigia; Griffini, Samantha; Grovetti, Elena; Berti, Emilio; Marzano, Angelo Valerio

2015-01-01

Coagulation activation has been demonstrated in two prototypic autoimmune skin diseases, chronic autoimmune urticaria and bullous pemphigoid, but only the latter is associated with increased thrombotic risk. Two markers of coagulation activation (prothrombin fragment F1+2 and fibrin fragment D-dimer) were measured by immunoenzymatic methods in plasma samples from 30 patients with active chronic autoimmune urticaria, positive for autologous serum skin test, 30 patients with active bullous pemphigoid and 30 healthy subjects. In skin biopsies, tissue factor expression was evaluated by both immunohistochemistry and in situ hybridization. F1+2 and D-dimer levels were higher in active chronic autoimmune urticaria (276.5±89.8 pmol/L and 5.56±4.40 nmol/L, respectively) than in controls (145.2±38.0 pmol/L and 1.06±0.25 nmol/L; P=0.029 and P=0.011) and were much higher in active bullous pemphigoid (691.7±318.7 pmol/L and 15.24±9.09 nmol/L, respectively) (P<0.0001). Tissue factor positivity was evident in skin biopsies of both disorders with higher intensity in bullous pemphigoid. F1+2 and D-dimer, during remission, were markedly reduced in both disorders. These findings support the involvement of coagulation activation in the pathophysiology of both diseases. The strong systemic activation of coagulation in bullous pemphigoid may contribute to increase the thrombotic risk and provides the rationale for clinical trials on anticoagulant treatments in this disease. PMID:26057532

Coagulation activation by MC28 fibrosarcoma cells facilitates lung tumor formation.

PubMed

Amirkhosravi, M; Francis, J L

1995-01-01

Tumor cells interact with the hemostatic system in various ways and may thus influence malignant growth and spread. MC28 fibrosarcoma cells possess a potent procoagulant activity (PCA) and form lung tumors following intravenous injection. The aim of this work was to study the relationship between PCA, intravascular coagulation and lung seeding in the MC28 model. MC28 cells were injected into control, warfarinized and heparinized hooded Lister rats. Coagulation changes were monitored by thromboelastography (TEG) and Sonoclot analysis (SA), lung fibrin formation by light and electron microscopy, tumor seeding by macroscopic counting and tumor cell and platelet deposition in the lungs by radiolabelling. PCA was measured by chromogenic assay. MC28 PCA was characterized as a tissue factor-factor VIIa complex that probably arose during cell culture or disaggregation of solid tumors. Injection of tumor cells caused marked coagulopathy and was rapidly (within 30 min) followed by fibrin deposition in the lungs and accumulation of radiolabelled platelets. Heparin and warfarin significantly reduced lung seeding (p < 0.001) and reduced retention of radiolabelled tumor cells in the pulmonary circulation (p < 0.01). Inhibition of cellular PCA by prior treatment with concanavalin A markedly reduced intravascular coagulation and lung seeding. We conclude that MC28 cells cause intravascular coagulation as a direct result of their procoagulant activity. The data suggest that tumor cells form complexes with platelets and fibrin which are retained in the lungs long enough for extravasation and seeding to occur.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterisation of clotting factors, anticoagulant protein activities and viscoelastic analysis in healthy donkeys.

PubMed

Perez-Ecija, A; Mendoza, F J

2017-11-01

Studies have demonstrated differences in commonly measured haemostatic parameters between donkeys and horses. Whether clotting factors, anticoagulant protein activities and thromboelastography parameters also differ between species is still unknown. To characterise haemostatic parameters in healthy donkeys and to compare these with those in horses. Cross-sectional study. Clotting factors (V, VII, VIII, IX, X, XI and XII), and antithrombin III, Protein C and Protein S activities were measured in 80 healthy Andalusian and crossbred donkeys and 40 healthy Andalusian crossbred horses with assays based on human deficient plasmas. Thromboelastography was performed in 34 donkeys using a coagulation and platelet function analyser. Donkeys had shorter activated partial thromboplastin time (mean ± s.d. 33.4 ± 5.2 s vs. 38.8 ± 4.2 s; P<0.001) and higher Factor VII (1825 ± 206 vs. 1513 ± 174; P<0.001), IX (142 ± 41 vs. 114 ± 28; P<0.05) and XI (59.4 ± 14.0 vs. 27.2 ± 6.3; P<0.001) activities, whereas horses showed higher Factor X (130 ± 32 vs. 145 ± 23; P>0.05) and XII (96 ± 21 vs. 108 ± 15; P<0.001) activities. Antithrombin III (204 ± 26 vs. 174 ± 29; P<0.001), Protein C (33.16 ± 10.0 vs. 7.57 ± 1.70; P<0.001) and Protein S (median [interquartile range]: 7.8 [5.8-9.3] vs. 6.2 [5.2-7.0]; P<0.001) activities were higher in donkeys. Activated clot time (175 [159-189]), time to peak (6.5 [5.8-7.8]) and clot formation rate (26.9 [16.9-36.4]) in donkeys were shorter than reported values in horses. Haemostatic pathways could not be fully evaluated in donkeys because some tests are unavailable. Certain fibrinolytic parameters (plasmin, plasminogen, etc.) have not been characterised in donkeys and this may have affected our results. The haemostatic system in donkeys differs from that in horses and extrapolation of reference values between these species is not appropriate. © 2017 EVJ Ltd.

Protein Z efficiently depletes thrombin generation in disseminated intravascular coagulation with poor prognosis.

PubMed

Lee, Nuri; Kim, Ji-Eun; Gu, Ja-Yoon; Yoo, Hyun Ju; Kim, Inho; Yoon, Sung-Soo; Park, Seonyang; Han, Kyou-Sup; Kim, Hyun Kyung

2016-01-01

Disseminated intravascular coagulation (DIC) is characterized by consumption of coagulation factors and anticoagulants. Thrombin generation assay (TGA) gives useful information about global hemostatic status. We developed a new TGA system that anticoagulant addition can deplete thrombin generation in plasma, which may reflect defective anticoagulant system in DIC. TGAs were measured on the calibrated automated thrombogram with and without thrombomodulin or protein Z in 152 patients who were suspected of having DIC, yielding four parameters including lag time, endogenous thrombin potential, peak thrombin and time-to-peak in each experiment. Nonsurvivors showed significantly prolonged lag time and time-to-peak in TGA-protein Z system, which was performed with added protein Z. In multivariate Cox regression analysis, lag time and time-to-peak in TGA system were significant independent prognostic factors. In TGA-protein Z system, lag time and time-to-peak were revealed as independent prognostic factors of DIC. Protein Z addition could potentiate its anticoagulant effect in DIC with poor prognosis, suggesting the presence of defective protein Z system. The prolonged lag time and time-to-peak in both TGA and TGA-protein Z systems are expected to be used as independent prognostic factors of DIC.

Coagulopathy induced by acidosis, hypothermia and hypocalcaemia in severe bleeding.

PubMed

De Robertis, E; Kozek-Langenecker, S A; Tufano, R; Romano, G M; Piazza, O; Zito Marinosci, G

2015-01-01

Acidosis, hypothermia and hypocalcaemia are determinants for morbidity and mortality during massive hemorrhages. However, precise pathological mechanisms of these environmental factors and their potential additive or synergistic anticoagulant and/or antiplatelet effects are not fully elucidated and are at least in part controversial. Best available evidences from experimental trials indicate that acidosis and hypothermia progressively impair platelet aggregability and clot formation. Considering the cell-based model of coagulation physiology, hypothermia predominantly prolongs the initiation phase, while acidosis prolongs the propagation phase of thrombin generation. Acidosis increases fibrinogen breakdown while hypothermia impairs its synthesis. Acidosis and hypothermia have additive effects. The effect of hypocalcaemia on coagulopathy is less investigated but it appears that below the cut-off of 0.9 mmol/L, several enzymatic steps in the plasmatic coagulation system are blocked while above that cut-off effects remain without clinical sequalae. The impact of environmental factor on hemostasis is underestimated in clinical practice due to our current practice of using routine coagulation laboratory tests such as partial thromboplastin time or prothrombin time, which are performed at standardized test temperature, after pH correction, and upon recalcification. Temperature-adjustments are feasible in viscoelastic point-of-care tests such as thrombelastography and thromboelastometry which may permit quantification of hypothermia-induced coagulopathy. Rewarming hypothermic bleeding patients is highly recommended because it improves patient outcome. Despite the absence of high-quality evidence, calcium supplementation is clinical routine in bleeding management. Buffer administration may not reverse acidosis-induced coagulopathy but may be essential for the efficacy of coagulation factor concentrates such as recombinant activated factor VII.

Simultaneous expression of tissue factor and tissue factor pathway inhibitor by human monocytes. A potential mechanism for localized control of blood coagulation

PubMed Central

1994-01-01

Cells of monocytic lineage can initiate extravascular fibrin deposition via expression of blood coagulation mediators. This report is about experiments on three mechanisms with the potential to modulate monocyte- initiated coagulation. Monocyte procoagulant activity was examined as a function of lipid cofactor, protein cofactor, and specific inhibitor expression during short-term culture in vitro. Lipid cofactor activity was measured as the initial rate of factor X activation by intrinsic- pathway components, the assembly of which depends on this cofactor. Lipid cofactor activity levels changed by < 30% during 48-h culture. Protein cofactor, i.e., tissue factor (TF) antigen was measured by enzyme immunoassay. It increased from 461 pg/ml to a maximum value of 3,550 pg/ml at 24 h and remained at 70% of this value. Specific TF activity, measured as factor VII-dependent factor X activation rate, decreased from 54 to 18 nM FXa/min between 24 and 48 h. TF activity did not correlate well with either lipid cofactor or TF protein levels. In contrast, the decrease in TF activity coincided in time with maximal expression of tissue factor pathway inhibitor (TFPI) mRNA, which was determined using reverse transcriptase polymerase chain reaction (RT- PCR), and with maximal TFPI protein levels measured by immunoassay. The number of mRNA copies coding for TFPI and TF in freshly isolated blood monocytes were 46 and 20 copies/cells, respectively. These values increased to 220 and 63 copies/cell during short-term cell culture in the presence of endotoxin. Results demonstrate concomitant expression by monocytes of genes coding for both the essential protein cofactor and the specific inhibitor of the extrinsic coagulation pathway. Together with functional and antigenic analyses, they also imply that the initiation of blood clotting by extravascular monocyte/macrophages can be modulated locally by TFPI independently of plasma sources of the inhibitor. PMID:8195712

Coagulation Profile as a Risk Factor for 30-Day Morbidity and Mortality Following Posterior Lumbar Fusion.

PubMed

Bronheim, Rachel S; Oermann, Eric K; Cho, Samuel K; Caridi, John M

2017-06-15

A retrospective cohort study. The aim of this study was to identify associations between abnormal coagulation profile and postoperative morbidity and mortality in patients undergoing posterior lumbar fusion (PLF). The literature suggests that abnormal coagulation profile is associated with postoperative complications, notably the need for blood transfusion. However, there is little research that directly addresses the influence of coagulation profile on postoperative complications following PLF. The American College of Surgeons National Surgical Quality Improvement Program database (ACS-NSQIP) was utilized to identify patients undergoing PLF between 2006 and 2013. Nine thousand two hundred ninety-five patients met inclusion criteria. Multivariate analysis was utilized to identify associations between abnormal coagulation profile and postoperative complications. Low platelet count was an independent risk factor for organ space surgical site infections (SSIs) [odds ratio (OR) = 6.0, P < 0.001], ventilation >48 hours (OR = 4.5, P = 0.002), Acute renal failure (OR = 5.8, P = 0.007), transfusion (OR = 1.6, P < 0.001), sepsis (OR = 2.2, P = 0.037), reoperation (OR = 2.5, P = 0.001), and death (OR = 3.7, P = 0.049). High partial thromboplastin time (PTT) was an independent risk factor for ventilation >48 hours (OR = 5.6, P = 0.002), cerebrovascular accident (CVA)/stroke with neurological deficit (OR = 5.1, P = 0.011), cardiac arrest (OR = 5.4, P = 0.030), transfusion (OR = 1.5, P = 0.020), and death (OR = 4.5, P = 0.050). High International Normalized Ration (INR) was an independent risk factor for pneumonia (OR = 8.7, P = 0.001), pulmonary embolism (OR = 5.6, P = 0.021), deep venous thrombosis/Thrombophlebitis (OR = 4.8, P = 0.011), septic shock (OR = 8.4, P = 0.048), and death (OR = 9.8, P = 0.034). Bleeding disorder was an independent risk factor for organ space SSI (OR = 5.4, P = 0.01), pneumonia (OR = 3.0, P = 0.023), and sepsis (OR = 4.4, P < 0.001). Abnormal coagulation profile was an independent predictor of morbidity and mortality in patients undergoing PLF. As such, it should be considered in preoperative optimization and risk stratification.

The unexpected finding of a splenic infarction in a patient with infectious mononucleosis due to Epstein-Barr virus

PubMed Central

Machado, Catarina; Melo Salgado, Joana; Monjardino, Leonor

2015-01-01

The authors present a case of a 24-year-old man with infectious mononucleosis (IM) due to Epstein-Barr virus (EBV). Among his symptoms, he reported abdominal pain in the upper left quadrant. An abdominal ultrasound and CT revealed an extensive splenic infarction. During the acute stage of this disease, the thrombophilic screening revealed reduced free protein S and elevated factor VIII, with normalisation on re-evaluation 6 weeks later. Splenic infarction is a very rare complication of IM due to EBV but should be considered in patients presenting abdominal pain. A hypercoagulability state should be investigated. To our knowledge, this is the first described case of a splenic infarction in a patient with IM due to EBV associated with a transient reduction of protein S and elevation of factor VIII. Thus, this work promotes the importance of including these factors in the thrombophilic screening conducted during the investigation of similar cases. PMID:26607191

The unexpected finding of a splenic infarction in a patient with infectious mononucleosis due to Epstein-Barr virus.

PubMed

Machado, Catarina; Melo Salgado, Joana; Monjardino, Leonor

2015-11-25

The authors present a case of a 24-year-old man with infectious mononucleosis (IM) due to Epstein-Barr virus (EBV). Among his symptoms, he reported abdominal pain in the upper left quadrant. An abdominal ultrasound and CT revealed an extensive splenic infarction. During the acute stage of this disease, the thrombophilic screening revealed reduced free protein S and elevated factor VIII, with normalisation on re-evaluation 6 weeks later. Splenic infarction is a very rare complication of IM due to EBV but should be considered in patients presenting abdominal pain. A hypercoagulability state should be investigated. To our knowledge, this is the first described case of a splenic infarction in a patient with IM due to EBV associated with a transient reduction of protein S and elevation of factor VIII. Thus, this work promotes the importance of including these factors in the thrombophilic screening conducted during the investigation of similar cases. 2015 BMJ Publishing Group Ltd.

Molecular cloning, characterization and expression analysis of coagulation factor VII gene in grass carp (Ctenopharyngodon idella).

PubMed

Liu, Qiaolin; Xu, Baohong; Xiao, Tiaoyi; Su, Jianming; Zhong, Lei

2013-08-01

Coagulation factor VII has been studied in several species but, to date, not in grass carp (Ctenopharyngodon idella), a commercially important freshwater fish found in China. In this study, the full-length cDNA of grass carp coagulation factor VII (GcCFVII) was cloned using a RACE-Ready cDNA Kit, grass carp were challenged with a hemorrhagic virus, and temporal expression profiles of GcCFVII in the thymus, gills, liver, spleen, and head kidney were examined at 0 h, 24 h, 48 h, 72 h, 96 h, and 138 h using fluorescence quantitative PCR. The results showed the 1480 bp GcCFVII to contain three conservative motifs: Gla, EGF-CA, and Tryp-SPc, similar to other species. Phylogenetic analysis showed the evolution of GcCFVII gene to be consistent with the evolution of the species. After viral challenge, GcCFVII expression in five tissues of grass carp showed different patterns of fluctuation. These results provide a solid basis for further investigation of GcCFVII and its relationship with grass carp hemorrhage. Copyright © 2013 Elsevier Ltd. All rights reserved.

Physiotherapy, rehabilitation and sports in countries with limited replacement coagulation factor supply.

PubMed

Buzzard, B M

2007-09-01

It is well documented that physiotherapy and rehabilitation benefit people with haemophilia by strengthening the key muscle groups and protecting joints from the adverse effects of repeated haemorrhages. Rehabilitation, in conjunction with the availability of replacement coagulation factor products, has revolutionized approaches to the management of patients with haemophilia in developed countries and has led to a substantial decrease in both the morbidity and mortality rates among the haemophilic population. Modern treatment approaches have also enabled persons with haemophilia to participate in sporting activities along with their peers; however, these improvements in care have not been achieved in developing nations, where health-care resources and facilities are scarce and the supply of coagulation factor products is limited. This article attempts to address the following questions about the management of haemophilic patients in developing countries: Can physiotherapy, rehabilitation and sports prevent disabilities and preserve independence? Is participation in sports activities possible in developing countries? Do countries differ with regard to guidelines for participation in sports? Should we be encouraging participation in sports or allowing patients with haemophilia to do as they choose?

Fat high in stearic acid favorably affects blood lipids and factor VII coagulant activity in comparison with fats high in palmitic acid or high in myristic and lauric acids.

PubMed

Tholstrup, T; Marckmann, P; Jespersen, J; Sandström, B

1994-02-01

The effect of fats high in individual, prevalent saturated dietary fatty acids on lipoproteins and hemostatic variables in young healthy subjects was evaluated in a randomized strictly controlled metabolic feeding study. Three experimental diets: shea butter (S; 42% stearic acid), palm oil (P; 43% palmitic palmitic acid), and palm-kernel oil with high-oleic sunflower oil (ML; 10% myristic acid, 30% lauric acid) were served to 15 men for 3 wk each, separated by washout periods. Diet S compared with diet P resulted in significant reduction in plasma cholesterol (22%) LDL cholesterol (26%), apolipoprotein B (18%), HDL cholesterol (12%), apolipoprotein A-I (13%), and a 13% lower factor VII coagulant activity (P = 0.001). Similar differences were observed between diets S and ML. In conclusion, intake of shea butter high in stearic acid favorably affects blood lipids and factor VII coagulant activity in young men, compared with fats high in saturated fatty acids with 12-16 carbons.

39 CFR 255.8 - Access to postal facilities.

Code of Federal Regulations, 2010 CFR

2010-07-01

... with the National Historic Preservation Act of 1966, 16 U.S.C. 470 et seq.; (vii) The availability of other options to foster service accessibility; and (viii) Any other factor that is relevant and...

Confinement regulates complex biochemical networks: initiation of blood clotting by "diffusion acting".

PubMed

Shen, Feng; Pompano, Rebecca R; Kastrup, Christian J; Ismagilov, Rustem F

2009-10-21

This study shows that environmental confinement strongly affects the activation of nonlinear reaction networks, such as blood coagulation (clotting), by small quantities of activators. Blood coagulation is sensitive to the local concentration of soluble activators, initiating only when the activators surpass a threshold concentration, and therefore is regulated by mass transport phenomena such as flow and diffusion. Here, diffusion was limited by decreasing the size of microfluidic chambers, and it was found that microparticles carrying either the classical stimulus, tissue factor, or a bacterial stimulus, Bacillus cereus, initiated coagulation of human platelet-poor plasma only when confined. A simple analytical argument and numerical model were used to describe the mechanism for this phenomenon: confinement causes diffusible activators to accumulate locally and surpass the threshold concentration. To interpret the results, a dimensionless confinement number, Cn, was used to describe whether a stimulus was confined, and a Damköhler number, Da(2), was used to describe whether a subthreshold stimulus could initiate coagulation. In the context of initiation of coagulation by bacteria, this mechanism can be thought of as "diffusion acting", which is distinct from "diffusion sensing". The ability of confinement and diffusion acting to change the outcome of coagulation suggests that confinement should also regulate other biological "on" and "off" processes that are controlled by thresholds.

The Loss of Homeostasis in Hemostasis: New Approaches in Treating and Understanding Acute Disseminated Intravascular Coagulation in Critically Ill Patients*

PubMed Central

Abrams, Charles S.

2012-01-01

Abstract Disseminated intravascular coagulation (DIC) profoundly increases the morbidity and mortality of patients who have sepsis. Both laboratory and clinical research advanced the understanding of the biology and pathophysiology of DIC. This, in turn, gave rise to improved therapies and patient outcomes. Beginning with a stimulus causing disruption of vascular integrity, cytokines and chemokines cause activation of systemic coagulation and inflammation. Seemingly paradoxically, the interplay between coagulation and inflammation also inhibits endogenous anticoagulants, fibrinolytics, and antiinflammatory pathways. The earliest documented and best‐studied microbial cause of DIC is the lipopolysaccharide endotoxin of Gram‐negative bacteria. Extensive microvascular thrombi emerge in the systemic vasculature due to dysregulation of coagulation. The result of this unrestrained, widespread small vessel thromboses multiorgan system failure. Consumption of platelets and coagulation factors during this process can lead to an elevated risk of hemorrhage. The management of these patients with simultaneous hemorrhage and thrombosis is complex and challenging. Definitive treatment of DIC, and attenuation of end‐organ damage, requires control of the inciting cause. Currently, activated protein C is the only approved therapy in the United States for sepsis complicated by DIC. Further research is needed in this area to improve clinical outcomes for patients with sepsis. Clin Trans Sci 2012; Volume 5: 85–92 PMID:22376264

Coagulation Abnormalities of Sickle Cell Disease: Relationship with Clinical Outcomes and the Effect of Disease Modifying Therapies

PubMed Central

Noubouossie, Denis; Key, Nigel S.; Ataga, Kenneth I.

2015-01-01

Sickle cell disease (SCD) is a hypercoagulable state. Patients exhibit increased platelet activation, high plasma levels of markers of thrombin generation, depletion of natural anticoagulant proteins, abnormal activation of the fibrinolytic system, and increased tissue factor expression, even in the non-crisis “steady state.” Furthermore, SCD is characterized by an increased risk of thrombotic complications. The pathogenesis of coagulation activation in SCD appears to be multi-factorial, with contributions from ischemia-reperfusion injury and inflammation, hemolysis and nitric oxide deficiency, and increased sickle RBC phosphatidylserine expression. Recent studies in animal models suggest that activation of coagulation may contribute to the pathogenesis of SCD, but the data on the contribution of coagulation and platelet activation to SCD-related complications in humans are limited. Clinical trials of new generations of anticoagulants and antiplatelet agents, using a variety of clinical endpoints are warranted. PMID:26776344

Enzymatic lipid oxidation by eosinophils propagates coagulation, hemostasis, and thrombotic disease

PubMed Central

Uderhardt, Stefan; Ackermann, Jochen A.; Fillep, Tobias; Hammond, Victoria J.; Willeit, Johann; Stark, Konstantin; Rossaint, Jan; Schubert, Irene; Mielenz, Dirk; Dietel, Barbara; Raaz-Schrauder, Dorette; Ay, Cihan; Thaler, Johannes; Heim, Christian; Collins, Peter W.; Schabbauer, Gernot; Mackman, Nigel; Voehringer, David; Nadler, Jerry L.; Lee, James J.; Massberg, Steffen; Rauh, Manfred; O’Donnell, Valerie B.

2017-01-01

Blood coagulation is essential for physiological hemostasis but simultaneously contributes to thrombotic disease. However, molecular and cellular events controlling initiation and propagation of coagulation are still incompletely understood. In this study, we demonstrate an unexpected role of eosinophils during plasmatic coagulation, hemostasis, and thrombosis. Using a large-scale epidemiological approach, we identified eosinophil cationic protein as an independent and predictive risk factor for thrombotic events in humans. Concurrent experiments showed that eosinophils contributed to intravascular thrombosis by exhibiting a strong endogenous thrombin-generation capacity that relied on the enzymatic generation and active provision of a procoagulant phospholipid surface enriched in 12/15-lipoxygenase–derived hydroxyeicosatetraenoic acid–phosphatidylethanolamines. Our findings reveal a previously unrecognized role of eosinophils and enzymatic lipid oxidation as regulatory elements that facilitate both hemostasis and thrombosis in response to vascular injury, thus identifying promising new targets for the treatment of thrombotic disease. PMID:28566277

Role of plasma kallikrein in diabetes and metabolism.

PubMed

Feener, E P; Zhou, Q; Fickweiler, W

2013-09-01

Plasma kallikrein (PK) is a serine protease generated from plasma prekallikrein, an abundant circulating zymogen expressed by the Klkb1 gene. The physiological actions of PK have been primarily attributed to its production of bradykinin and activation of coagulation factor XII, which promotes inflammation and the intrinsic coagulation pathway. Recent genetic, molecular, and pharmacological studies of PK have provided further insight into its role in physiology and disease. Genetic analyses have revealed common Klkb1 variants that are association with blood metabolite levels, hypertension, and coagulation. Characterisation of animal models with Klkb1 deficiency and PK inhibition have demonstrated effects on inflammation, vascular function, blood pressure regulation, thrombosis, haemostasis, and metabolism. These reports have also identified a host of PK substrates and interactions, which suggest an expanded physiological role for this protease beyond the bradykinin system and coagulation. The review summarises the mechanisms that contribute to PK activation and its emerging role in diabetes and metabolism.

The role of protease-activated receptors PAR-1 and PAR-2 in the repair of 16HBE 14o(-) epithelial cell monolayers in vitro.

PubMed

Ewen, D; Clarke, S L; Smith, J R; Berger, C; Salmon, G; Trevethick, M; Shute, J K

2010-03-01

We recently reported that repair following mechanical wounding of epithelial cell layers in vitro is dependent on fibrin formation and the activity of locally expressed coagulation cascade proteins. Serine proteases of the coagulation cascade are an important group of protease-activated receptor (PAR) activators and PAR-1 to 4 are expressed by the normal bronchial epithelium. We tested the hypothesis that activation of PAR-1 and PAR-2 by coagulation cascade proteases stimulates epithelial repair via effects on fibrin formation. Using mechanically wounded 16HBE 14o(-) epithelial cell layers in culture, we investigated the effect of PAR-1 and PAR-2 agonist peptides, control partially scrambled peptides and PAR-neutralizing antibodies on the rate of repair and fibrin formation. Coagulation factors in culture supernatants were measured by immunoblot. RT-PCR was used to investigate PAR-1, PAR-2 and PGE2 receptor (EP-1 to EP-4) expression in this model and qRT-PCR to quantify responses to wounding. Additionally, we investigated the effect of exogenously added factor Xa (FXa) and neutrophil elastase and the influence of PGE2 and indomethacin on the repair response. PAR-1 and PAR-2 peptide agonists stimulated the rate of repair and enhanced the formation of a fibrin provisional matrix to support the repair process. Conversely, PAR-neutralizing antibodies inhibited repair. Under serum-free culture conditions, 16HBE 14o(-) cells expressed EP-2 and EP-3, but not EP-1 or EP-4, receptors. Wounding induced an increased expression of EP-3 but did not alter EP-2, PAR-1 or PAR-2 expression. In the absence of PAR agonists, there was no evidence for a role for PGE2 in fibrin formation or the repair process. Indomethacin attenuated fibrin formation in wounded cultures only in the presence of the PAR-2 peptide. FXa stimulated epithelial repair while neutrophil elastase reduced the levels of coagulation factors and inhibited repair. Locally expressed serine proteases of the coagulation cascade activate PAR-1 and PAR-2 to enhance fibrin formation and bronchial epithelial repair.

12 CFR 611.1137 - Title VIII service corporations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Title VIII service corporations. 611.1137 Section 611.1137 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM ORGANIZATION Service Organizations § 611.1137 Title VIII service corporations. (a) What is a title VIII service corporation? A title...

Analysis of the Strategy to Combat Maritime Piracy

DTIC Science & Technology

2009-12-11

26  Contemporary Maritime Piracy: Causative Factors...NSC National Security Council PUC Persons Under Control viii SLOC Sea lines of communication SSA Ships Security Assessment SSP Ships Security Plan...UNCLOS United Nations Convention on the Law of the Sea USD United States Dollar U.S. United States ix ILLUSTRATIONS Page Figure 1.  Factors

Purchasing factor concentrates in the 21st century through competitive tendering.

PubMed

Hay, C R M

2013-09-01

The increasing intensity of treatment, the widespread adoption of factor VIII and IX prophylaxis and increasing usage over the past decade have led to haemophilia becoming an almost uniquely expensive condition to treat. The average adult with severe haemophilia A in the UK used 250,000 IU of factor VIII in 2011/2012, at a cost in excess of £ 100,000 p.a. The cost to the end-user may be considerably higher than this for some US patients supplied by home care companies with high on-costs. This has led to a high level of administrative scrutiny of treatment and an imperative to procure clotting factor concentrates more efficiently and collectively. National procurement schemes have run successfully in various countries and will become commoner. The UK system of procurement is described. This system, following EU procurement rules, evaluated products technically and by price. The price of bioequivalent products was determined by reverse e-auction. Considerable cost reductions were achieved whilst retaining all suppliers and maintaining a degree of prescribing freedom. Elements of this system could be more widely applied. © 2013 John Wiley & Sons Ltd.

Recombinant to modified factor VIII and factor IX - chromogenic and one-stage assays issues.

PubMed

Kitchen, S; Kershaw, G; Tiefenbacher, S

2016-07-01

The recent development of modified recombinant factor VIII (FVIII) and factor IX (FIX) therapeutic products with extended half-lives will create challenges for the haemostasis laboratory in obtaining recovery estimates of these products in clinical samples using existing assays. The new long-acting therapeutic concentrates contain molecular modifications of Fc fusion, site-specific of polyethylene glycol or albumin fusion. The optimum methods for monitoring each new product will need to be assessed individually and laboratories should select an assay which gives similar results to the assay used to assign potency to the product in question. For some extended half-life FVIII and FIX products some one stage assays are entirely unsuitable for monitoring purposes. For most products and assay reagents studied so far, and reviewed in this manuscript, chromogenic FVIII or FIX assays can be safely used with conventional plasma standards. If one stage assays are used then they should be performed using carefully selected reagents/methods which have been shown to recover activity close to the labelled potency for the specific product being monitored. © 2016 John Wiley & Sons Ltd.

Coagulation removal of humic acid-stabilized carbon nanotubes from water by PACl: influences of hydraulic condition and water chemistry.

PubMed

Ma, Si; Liu, Changli; Yang, Kun; Lin, Daohui

2012-11-15

Discharged carbon nanotubes (CNTs) can adsorb the widely-distributed humic acid (HA) in aquatic environments and thus be stabilized. HA-stabilized CNTs can find their way into and challenge the potable water treatment system. This study investigated the efficiency of coagulation and sedimentation techniques in the removal of the HA-stabilized multi-walled carbon nanotubes (MWCNTs) using polyaluminum chloride (PACl) as a coagulant, with a focus on the effects of hydraulic conditions and water chemistry. Stirring speeds in the mixing and reacting stages were gradually changed to examine the effect of the hydraulic conditions on the removal rate. The stirring speed in the reacting stage affected floc formation and thereby had a greater impact on the removal rate than the stirring speed in the mixing stage. Water chemistry factors such as pH and ionic strength had a significant effect on the stability of MWCNT suspension and the removal efficiency. Low pH (4-7) was favorable for saving the coagulant and maintaining high removal efficiency. High ionic strength facilitated the destabilization of the HA-stabilized MWCNTs and thereby lowered the required PACl dosage for the coagulation. However, excessively high ionic strength (higher than the critical coagulation concentration) decreased the maximum removal rate, probably by inhibiting ionic activity of PACl hydrolyzate in water. These results are expected to shed light on the potential improvement of coagulation removal of aqueous stabilized MWCNTs in water treatment systems. Copyright © 2012 Elsevier B.V. All rights reserved.

[Effects on phenol removal in the process of enhanced coagulation by manganese dioxide formed in situ].

PubMed

Zhang, Li-Zhu; Chen, Xiao-Dong; Ma, Jun; Yu, Min; Li, Xin

2011-10-01

Phenol was selected as a model compound. Factors, such as Ca2+, tannic acid, dose of kaolinite, dose of manganese dioxide formed in situ and pH, were invested on phenol removal in the process of enhanced coagulation by manganese dioxide formed in situ. Results showed that the addition of Ca2+ is beneficial for phenol removal. In the range of Ca2+ varied from 0 to 1.0 mmol x L(-1), the efficiency of phenol removal was enhanced more than 10%. Tannic acid can enhance phenol removal significantly when they are coexisted in water. As tannic acid was added to 10 mg x L(-1), phenol removal can be increased about 30% and 50% in the process of coagulation by AlCl3 and enhanced coagulation by manganese dioxide formed in situ, respectively. The dose of coagulant can be reduced in the process of enhanced coagulation with the addition of manganese dioxide formed in situ. The point of 1 mg x L(-1) manganese dioxide formed in situ linked with 30 mg x L(-1) AlCl3 can have the same phenol removal efficiency as the addition of 50 mg x L(-1) AlCl3. In the range of pH varied from 5 to 9, phenol can be removed with the high efficiency in the process of enhanced coagulation by manganese dioxide formed in situ. While under the strong acid condition and strong basic condition, phenol has lower removal efficiency.

Effects of oversulfated and fucosylated chondroitin sulfates on coagulation. Challenges for the study of anticoagulant polysaccharides.

PubMed

Fonseca, Roberto J C; Oliveira, Stephan-Nicollas M C G; Pomin, Vitor H; Mecawi, André S; Araujo, Iracema G; Mourão, Paulo A S

2010-05-01

We report the effects of a chemically oversulfated chondroitin sulfate and a naturally fucosylated chondroitin sulfate on the coagulation system. The former has been recently identified as a contaminant of heparin preparations and the latter has been proposed as an alternative anticoagulant. The mechanism of action of these polymers on coagulation is complex and target different components of the coagulation system. They have serpin-independent anticoagulant activity, which preponderates in plasma. They also have serpin-dependent anticoagulant activity but differ significantly in the target coagulation protease and preferential serpin. Their anticoagulant effects differ even more markedly when tested as inhibitors of coagulation proteases using plasma as a source of serpins. It is possible that the difference is due to the high availability of fucosylated chondroitin sulfate whereas oversulfated chondroitin sulfate has strong unspecific binding to plasma protein and low availability for the binding to serpins. When tested using a venous thrombosis experimental model, oversulfated chondroitin sulfate is less potent as an antithrombotic agent than fucosylated chondroitin sulfate. These highly sulfated chondroitin sulfates activate factor XII in in vitro assays, based on kallikrein release. However, only fucosylated chondroitin sulfate induces hypotension when intravenously injected into rats. In conclusion, the complexity of the regulatory mechanisms involved in the action of highly sulfated polysaccharides in coagulation requires their analysis by a combination of in vitro and in vivo assays. Our results are relevant due to the urgent need for new anticoagulant drugs or alternative sources of heparin.

Measurement of the coagulation dynamics of bovine liver using the modified microscopic Beer-Lambert law.

PubMed

Terenji, Albert; Willmann, Stefan; Osterholz, Jens; Hering, Peter; Schwarzmaier, Hans-Joachim

2005-06-01

During heating, the optical properties of biological tissues change with the coagulation state. In this study, we propose a technique, which uses these changes to monitor the coagulation process during laser-induced interstitial thermotherapy (LITT). Untreated and coagulated (water bath, temperatures between 35 degrees C and 90 degrees C for 20 minutes.) samples of bovine liver tissue were examined using a Nd:YAG (lambda = 1064 nm) frequency-domain reflectance spectrometer. We determined the time integrated intensities (I(DC)) and the phase shifts (Phi) of the photon density waves after migration through the tissue. From these measured quantities, the time of flight (TOF) of the photons and the absorption coefficients of the samples were derived using the modified microscopic Beer-Lambert law. The absorption coefficients of the liver samples decreased significantly with the temperature in the range between 50 degrees C and 70 degrees C. At the same time, the TOF of the investigated photos was found increased indicating an increased scattering. The coagulation dynamics could be well described using the Arrhenius formalism with the activation energy of 106 kJ/mol and the frequency factor of 1.59 x 10(13)/second. Frequency-domain reflectance spectroscopy in combination with the modified microscopic Beer-Lambert (MBL) is suitable to measure heat induced changes in the absorption and scattering properties of bovine liver in vitro. The technique may be used to monitor the coagulation dynamics during local thermo-coagulation in vivo. Copyright 2005 Wiley-Liss, Inc.

Activation of coagulation and endothelium with concurrent impairment of anticoagulant mechanisms in patients with typhoid fever.

PubMed

de Jong, Hanna K; Parry, Chris M; van der Vaart, Thomas W; Kager, Liesbeth M; van den Ende, Stannie J; Maude, Rapeephan R; Wijedoru, Lalith; Ghose, Aniruddha; Hassan, Mohammed U; Hossain, Mohammed A; Dondorp, Arjan M; Baker, Steve; Faiz, M Abul; Meijers, Joost C M; Wiersinga, W Joost

2018-05-07

Typhoid fever caused by Salmonella Typhi remains a major burden worldwide. Gastrointestinal bleeding can be seen in up to 10 percent of patients and may be fatal. The coagulopathy, which may be the driver of this severe complication in patients with typhoid fever, however is ill defined. The aim of this study was to evaluate the activation of coagulation, anticoagulation, and fibrinolysis in patients with acute typhoid fever. Parameters of coagulation and fibrinolysis were measured in 28 hospitalized patients with culture-confirmed or PCR-confirmed typhoid fever and compared to 38 age- and sex-matched healthy volunteers. Patients demonstrated activation of the coagulation system, as reflected by elevated in vitro thrombin generation and high plasma levels of fibrinogen, D-dimer and prothrombin fragment F1 + 2 in concert with consumption of coagulation factors resulting in a prolonged prothrombin-time and activated-partial-thromboplastin-time. Concurrently, the anticoagulant proteins, protein C and antithrombin, were significantly lower in comparison to healthy controls. Patients also demonstrated evidence of activation and inhibition of fibrinolysis and a marked activation of endothelial cells. The extent of coagulation activation was associated with the course of the disease, repeated testing during convalescence showed a return toward normal values. Activation of coagulation is an important clinical feature of typhoid fever and is associated with severity of disease. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Characterization of factor VIII pharmaceutical preparations by means of MudPIT proteomic approach.

PubMed

Basilico, Fabrizio; Nardini, Ilaria; Mori, Filippo; Brambilla, Elena; Benazzi, Louise; De Palma, Antonella; Rosti, Enrico; Farina, Claudio; Mauri, PierLuigi

2010-09-21

For a good clinical outcome of Haemophilia A substitutive therapy a detailed characterization of factor VIII (FVIII) concentrates is required, in order to disclose the eventual relations between differently composed concentrates and their biological effects. This preliminary work could be a first step towards a deep structural characterization of FVIII concentrates, using the fast and simply manageable MudPIT technology, which enables the identification and characterization of protein mixtures taking advantage of both the high separation capacity of two-dimensional chromatography and the powerful peptide characterization ability of tandem mass spectrometry. The aim of this study was to evaluate the suitability of for the characterization of FVIII molecule in complex mixtures such its commercial concentrates, both plasma-derived and recombinant, and for the determination of the protein composition of different FVIII preparations. By means of Multidimensional Protein Identification Technology (MudPIT) it was possible to assess the presence of factor VIII in its preparations and to identify most of the contaminant proteins without gel separation. In particular, 125 and 42 proteins were identified in plasma-derived and recombinant concentrates, respectively. Concerning investigation of FVIII, 24 different peptides were identified in plasma-derived corresponding to 7, 29, 27, 19 and 67 of percentage coverage for A1, A2, A3, C1 and C2 domains, respectively. About its multimeric carrier von Willebrand factor (VWF), we have sequenced 42% of domain interacting with A3 and C2 domains of FVIII. Finally, it has been observed that normalized parameters, such as total peptide hits obtained by SEQUEST may be used for evaluation of the relative abundance of FVIII in different preparations. Copyright 2010 Elsevier B.V. All rights reserved.

Short communication: Prediction of milk coagulation and acidity traits in Mediterranean buffalo milk using Fourier-transform mid-infrared spectroscopy.

PubMed

Manuelian, C L; Visentin, G; Boselli, C; Giangolini, G; Cassandro, M; De Marchi, M

2017-09-01

Milk coagulation and acidity traits are important factors to inform the cheesemaking process. Those traits have been deeply studied in bovine milk, whereas scarce information is available for buffalo milk. However, the dairy industry is interested in a method to determine milk coagulation and acidity features quickly and in a cost-effective manner, which could be provided by Fourier-transform mid-infrared (FT-MIR) spectroscopy. The aim of this study was to evaluate the potential of FT-MIR to predict coagulation and acidity traits of Mediterranean buffalo milk. A total of 654 records from 36 herds located in central Italy with information on milk yield, somatic cell score, milk chemical composition, milk acidity [pH, titratable acidity (TA)], and milk coagulation properties (rennet coagulation time, curd firming time, and curd firmness) were available for statistical analysis. Reference measures of milk acidity and coagulation properties were matched with milk spectral information, and FT-MIR prediction models were built using partial least squares regression. The data set was divided into a calibration set (75%) and a validation set (25%). The capacity of FT-MIR spectroscopy to correctly classify milk samples based on their renneting ability was evaluated by a canonical discriminant analysis. Average values for milk coagulation traits were 13.32 min, 3.24 min, and 39.27 mm for rennet coagulation time, curd firming time, and curd firmness, respectively. Milk acidity traits averaged 6.66 (pH) and 7.22 Soxhlet-Henkel degrees/100 mL (TA). All milk coagulation and acidity traits, except for pH, had high variability (17 to 46%). Prediction models of coagulation traits were moderately to scarcely accurate, whereas the coefficients of determination of external validation were 0.76 and 0.66 for pH and TA, respectively. Canonical discriminant analysis indicated that information on milk coagulating ability is present in the MIR spectra, and the model correctly classified as noncoagulating the 91.57 and 67.86% of milk samples in the calibration and validation sets, respectively. In conclusion, our results can be relevant to the dairy industry to classify buffalo milk samples before processing. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Coagulation Profile as a Risk Factor for 30-day Morbidity Following Cervical Laminectomy and Fusion.

PubMed

Bronheim, Rachel S; Oermann, Eric K; Cho, Samuel K; Caridi, John M

2018-02-15

Retrospective analysis of prospectively collected data. The aim of this study was to determine the ability of abnormal coagulation profile to predict adverse events following posterior cervical laminectomy and fusion (PCLF). PCLF is an increasingly common procedure used to treat a variety of traumatic and degenerative spinal conditions. Abnormal coagulation profile is associated with postoperative adverse events, including blood transfusion. There is a paucity of literature that specifically addresses the relationship between coagulation profile and complications following PCLF. ACS-NSQIP was utilized to identify patients undergoing PCLF between 2006 and 2013. A total of 3546 patients met inclusion criteria. Multivariate analysis was utilized to identify associations between abnormal coagulation profile and postoperative complications. Membership in the low-platelet cohort was an independent risk factor for myocardial infarction (Odds Ratio (OR) = 5.4 [1.0, 29.1], P = 0.049) and bleeding transfusion (OR = 2.0 [1.2, 3.4], P = 0.011). Membership in the high international normalized ratio group was an independent risk factor for pneumonia (OR = 6.3 [2.5, 16.1], P < 0.001), ventilation >48 hours (OR = 6.5 [2.3, 18.4], P < 0.001), organ space surgical site infection (OR = 11.1 [2.1, 57.3], P = 0.004), urinary tract infection (OR = 3.0 [1.2, 8.0], P = 0.024), bleeding transfusion (OR = 6.0 [3.4, 10.7], P < 0.001), sepsis (OR = 5.1 [1.6, 16.4], P = 0.006), and septic shock (OR = 6.8 [1.7, 27.4], P = 0.007). Membership in the bleeding disorders cohort was an independent predictor of unplanned intubation (OR = 3.2 [1.1, 9.5], P = 0.041), pneumonia (OR = 2.9 [1.2, 7.2], P = 0.023), ventilation >48 hours (OR = 4.8 [1.9, 12.4], P = 0.001), cerebrovascular accident/stroke with neurological deficit (OR = 24.8 [2.9, 210.6], P = 0.003), bleeding transfusion (OR = 2.1 [1.1, 4.1], P = 0.032), reoperation (OR = 3.6 [1.4, 9.3], P = 0.008), and sepsis (OR = 3.4 [1.1, 10.4], P = 0.031). This is the first large study to document abnormal coagulation profile as an independent predictor of outcomes following PCLF. Abnormal coagulation profile represents a predictor of complications that can be medically mitigated, and is therefore a valuable parameter to assess preoperatively. Coagulation profile should continue to play a role in targeting patients for risk stratification, preoperative optimization, and quality improvement initiatives. 3.

[Molecular genetic analysis for a pedigree with severe hereditary coagulation factor VII deficiency].

PubMed

Ding, Qiu-lan; Wang, Hong-li; Wang, Xue-feng; Wang, Ming-shan; Fu, Qi-hua; Wu, Wen-man; Hu, Yi-qun; Wang, Zhen-yi

2003-10-01

To identify the genetic mutations of a severe inherited coagulation factor VII (FVII) deficiency pedigree. The diagnosis was validated by coagulant and haemostatic parameters. FVII gene mutations were screened in the propositus and his family members by DNA direct sequencing and confirmed by digestions of the restriction enzymes of the PCR production. Two heterozygous missense mutations were found in the propositus of the pedigree: a G to T transversion at position 9482 in exon 6 and a C to T mutation at position 11348 in exon 8 resulting in the amino acid substitution of Arg152 with Leu and Arg304 with Trp, respectively. A heterozygous single nucleotide deletion (C) at position 11487-11489(CCC) within exon 8 was identified, which predicted the frameshift mutation at position His351 followed by the changes of six corresponding amino acids and appearance of a premature protein caused by stop codon. The heterozygous mutations identified in the proband were derived from his father (Arg152 to Leu) and his mother (Arg304 to Trp mutation) and a heterozygous deletion (C) at position 11487-9(CCC). By tracing the other pedigree members, it was found that his grandmother had a heterozygous mutation of Arg304Trp and a heterozygous polymorphism of Arg353Gln and his grandfather had a heterozygous Arg152Leu mutation. Three heterozygous mutations were found in a pedigree with hereditary coagulation factor VII deficiency. Arg152Leu and deletion C at position 11487-9(CCC) were novel mutations.

The Carmat Bioprosthetic Total Artificial Heart Is Associated With Early Hemostatic Recovery and no Acquired von Willebrand Syndrome in Calves.

PubMed

Smadja, David M; Susen, Sophie; Rauch, Antoine; Cholley, Bernard; Latrémouille, Christian; Duveau, Daniel; Zilberstein, Luca; Méléard, Denis; Boughenou, Marie-Fazia; Belle, Eric Van; Gaussem, Pascale; Capel, Antoine; Jansen, Piet; Carpentier, Alain

2017-10-01

To determine hemostasis perturbations, including von Willebrand factor (VWF) multimers, after implantation of a new bioprosthetic and pulsatile total artificial heart (TAH). Preclinical study SETTING: Single-center biosurgical research laboratory. Female Charolais calves, 2-to-6 months old, weighing 102-to-122 kg. Surgical implantation of TAH through a mid-sternotomy approach. Four of 12 calves had a support duration of several days (4, 4, 8, and 10 days), allowing for the exploration of early steps of hemostasis parameters, including prothrombin time; coagulation factor levels (II, V, VII+X, and fibrinogen); and platelet count. Multimeric analysis of VWF was performed to detect a potential loss of high-molecular weight (HMW) multimers, as previously described for continuous flow rotary blood pumps. Despite the absence of anticoagulant treatment administered in the postoperative phase, no signs of coagulation activation were detected. Indeed, after an immediate postsurgery decrease of prothrombin time, platelet count, and coagulation factor levels, most parameters returned to baseline values. HMW multimers of VWF remained stable either after initiation or during days of support. Coagulation parameters and platelet count recovery in the postoperative phase of the Carmat TAH (Camat SA, Velizy Villacoublay Cedex, France) implantation in calves, in the absence of anticoagulant treatment and associated with the absence of decrease in HMW multimers of VWF, is in line with early hemocompatibility that is currently being validated in human clinical studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of Mg/Ga and V/III source ratios on hole concentration of N-polar (000\\bar{1}) p-type GaN grown by metalorganic vapor phase epitaxy

NASA Astrophysics Data System (ADS)

Nonoda, Ryohei; Shojiki, Kanako; Tanikawa, Tomoyuki; Kuboya, Shigeyuki; Katayama, Ryuji; Matsuoka, Takashi

2016-05-01

The effects of growth conditions such as Mg/Ga and V/III ratios on the properties of N-polar (000\\bar{1}) p-type GaN grown by metalorganic vapor phase epitaxy were studied. Photoluminescence spectra from Mg-doped GaN depended on Mg/Ga and V/III ratios. For the lightly doped samples, the band-to-acceptor emission was observed at 3.3 eV and its relative intensity decreased with increasing V/III ratio. For the heavily doped samples, the donor-acceptor pair emission was observed at 2.8 eV and its peak intensity monotonically decreased with V/III ratio. The hole concentration was maximum for the Mg/Ga ratio. This is the same tendency as in group-III polar (0001) growth. The V/III ratio also reduced the hole concentration. The higher V/III ratio reduced the concentration of residual donors such as oxygen by substituting nitrogen atoms. The surface became rougher with increasing V/III ratio and the hillock density increased.

Cyclophosphamide Treatment for Acquired Factor VIII Inhibitor in a Patient with AIDS-Associated Progressive Multifocal Leukoencephalopathy.

PubMed

Malhotra, Uma; Aboulafia, David M

2016-01-01

Acquired hemophilia A (AHA) is a severe bleeding disorder with high mortality rates resulting from the development of autoantibodies to factor VIII (FVIII). Patients typically present with hemorrhages in the skin, subcutaneous tissues, and muscles, which are frequently severe. They can also develop life-threatening retroperitoneal hematomas and compartment syndromes. We describe the case of a man with a long history of AIDS complicated by progressive multifocal leukoencephalopathy (PML), who developed AHA while on stable antiretroviral therapy and then presented with new onset bleeding and hypotension. We treated our patient with incrementally increasing doses of cyclophosphamide resulting in resolution of coagulopathy. We review the medical literature for additional cases of HIV-associated AHA and discuss the challenges in the care of our patient, since the immunosuppression needed to eradicate the FVIII inhibitor had the potential to cause recrudescence of his PML. © The Author(s) 2015.

Thromboelastography during coronary artery bypass grafting surgery of severe hemophilia A patient - the effect of heparin and protamine on factor VIII activity.

PubMed

Misgav, Mudi; Mandelbaum, Tal; Kassif, Yigal; Berkenstadt, Haim; Tamarin, Ilia; Kenet, Gili

2017-06-01

: Coronary artery bypass grafting surgery (CABG) in hemophilia patients is challenging. Thromboelastography (TEG) is useful to assess hemostasis perioperatively. A patient with severe hemophilia A underwent CABG with TEG studies. After factor VIII (FVIII) bolus dose, TEG was normalized. Following 'on-pump' heparinization, protamine administration revealed prolonged TEG-R and TEG-R with heparinase confirming it, whereas the activated clotting time was normal, suggesting low FVIII activity rather than excess of heparin. Another FVIII bolus yielded complete normalization of all TEG parameters. Data are compatible with in-vitro assays performed in our laboratory, showing that both heparin and protamine may impair measurable FVIII activity. The rational use of TEG measurements enabled more accurate hemostatic therapy application with regard to FVIII, heparin and protamine administration. Adopting this approach may lead to a better therapy tailoring for hemophilia patients undergoing CABG surgery.

Thrombomodulin as a marker for vascular tumors. Comparative study with factor VIII and Ulex europaeus I lectin.

PubMed

Yonezawa, S; Maruyama, I; Sakae, K; Igata, A; Majerus, P W; Sato, E

1987-10-01

Thrombomodulin (TM) is a newly described endothelial cell-associated protein that functions as a potent natural anticoagulant by converting thrombin from a procoagulant protease to an anticoagulant. Various vascular tumors were characterized with immunoperoxidase staining with the use of a polyclonal anti-TM serum. The staining patterns of TM were compared with those of Factor VIII-related antigen (FVIII-RAG) and Ulex europaeus agglutinin-I (UEA-I), which have been used as markers for endothelial cells. The results showed that TM is a specific and a highly sensitive marker for angiosarcomas in comparison with FVIII-RAG or UEA-I. In contrast, UEA-I is more sensitive for benign vascular tumors than TM or FVIII-RAG. The other mesenchymal tumors of nonvascular origin showed negative staining for three endothelial markers. These results indicate that TM is a new specific and sensitive tool for the diagnosis of angiosarcomas.