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 The few studies available on the biological variations of coagulation parameters are mostly outdated.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.

Functional consequences of an arginine180 to glutamine mutation in factor IX Hilo.

PubMed

Monroe, D M; McCord, D M; Huang, M N; High, K A; Lundblad, R L; Kasper, C K; Roberts, H R

1989-05-01

Factor IX Hilo is a variant factor IX molecule that has no detectable coagulant activity. The defect in factor IX Hilo arises from a point mutation in the gene such that in the protein Arg180 is converted to a Gln. Activation of factor IX Hilo by factor Xla was monitored using the fluorescent active site probe p-aminobenzamidine. Normal factor IX showed complete activation in one hour as determined by measuring the increase in fluorescence when p-aminobenzamidine bound to activated factor IX. Factor IX Hilo showed no increase in fluorescence even after 24 hours, indicating that the active site was not exposed. Polyacrylamide gel electrophoresis showed that factor IX Hilo was cleaved to a light chain plus a larger peptide with a molecular weight equivalent to a heavy chain covalently linked to an activation peptide. Amino terminal amino acid sequencing of factor IX Hilo cleaved by factor Xla showed cleavage only at Arg145-Ala146, indicating that the Gln180-Val181 bond was not cleaved and that the active site was thus not exposed. The presence of factor IX Hilo in patient plasma was responsible for the patient having a very long ox brain prothrombin time characteristic of severe hemophilia Bm. Patient plasma had an ox brain prothrombin time of 100 seconds using a Thrombotest kit, significantly prolonged over the normal control value of 45 seconds. When factor IX Hilo was depleted from patient plasma using an immunoaffinity column, the ox brain prothrombin time decreased to 41 seconds. When factor IX Hilo was added back to depleted patient plasma, to normal plasma depleted of factor IX by the same affinity column, or to plasma from a CRM- hemophilia B patient, the ox brain prothrombin time was significantly prolonged. We conclude that the Arg180 to Gln mutation in factor IX Hilo results in a molecule that cannot be activated by factor Xla. Further, our data suggest that the mutation results in a molecule that interacts with components of the extrinsic pathway to give a prolonged ox brain prothrombin time.

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.

Model of a ternary complex between activated factor VII, tissue factor and factor IX.

PubMed

Chen, Shu-wen W; Pellequer, Jean-Luc; Schved, Jean-François; Giansily-Blaizot, Muriel

2002-07-01

Upon binding to tissue factor, FVIIa triggers coagulation by activating vitamin K-dependent zymogens, factor IX (FIX) and factor X (FX). To understand recognition mechanisms in the initiation step of the coagulation cascade, we present a three-dimensional model of the ternary complex between FVIIa:TF:FIX. This model was built using a full-space search algorithm in combination with computational graphics. With the known crystallographic complex FVIIa:TF kept fixed, the FIX docking was performed first with FIX Gla-EGF1 domains, followed by the FIX protease/EGF2 domains. Because the FIXa crystal structure lacks electron density for the Gla domain, we constructed a chimeric FIX molecule that contains the Gla-EGF1 domains of FVIIa and the EGF2-protease domains of FIXa. The FVIIa:TF:FIX complex has been extensively challenged against experimental data including site-directed mutagenesis, inhibitory peptide data, haemophilia B database mutations, inhibitor antibodies and a novel exosite binding inhibitor peptide. This FVIIa:TF:FIX complex provides a powerful tool to study the regulation of FVIIa production and presents new avenues for developing therapeutic inhibitory compounds of FVIIa:TF:substrate complex.

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

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

The first EGF domain of coagulation factor IX attenuates cell adhesion and induces apoptosis.

PubMed

Ishikawa, Tomomi; Kitano, Hisataka; Mamiya, Atsushi; Kokubun, Shinichiro; Hidai, Chiaki

2016-07-01

Coagulation factor IX (FIX) is an essential plasma protein for blood coagulation. The first epidermal growth factor (EGF) motif of FIX (EGF-F9) has been reported to attenuate cell adhesion to the extracellular matrix (ECM). The purpose of the present study was to determine the effects of this motif on cell adhesion and apoptosis. Treatment with a recombinant EGF-F9 attenuated cell adhesion to the ECM within 10 min. De-adhesion assays with native FIX recombinant FIX deletion mutant proteins suggested that the de-adhesion activity of EGF-F9 requires the same process of FIX activation as that which occurs for coagulation activity. The recombinant EGF-F9 increased lactate dehydrogenase (LDH) activity release into the medium and increased the number of cells stained with annexin V and activated caspase-3, by 8.8- and 2.7-fold respectively, indicating that EGF-F9 induced apoptosis. Activated caspase-3 increased very rapidly after only 5 min of administration of recombinant EGF-F9. Treatment with EGF-F9 increased the level of phosphorylated p38 mitogen-activated protein kinase (MAPK), but not that of phosphorylated MAPK 44/42 or c-Jun N-terminal kinase (JNK). Inhibitors of caspase-3 suppressed the release of LDH. Caspase-3 inhibitors also suppressed the attenuation of cell adhesion and phosphorylation of p38 MAPK by EGF-F9. Our data indicated that EGF-F9 activated signals for apoptosis and induced de-adhesion in a caspase-3 dependent manner. © 2016 The Author(s).

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 new manufacturing process to remove thrombogenic factors (II, VII, IX, X, and XI) from intravenous immunoglobulin gamma preparations.

PubMed

Park, Dong Hwarn; Kang, Gil Bu; Kang, Dae Eun; Hong, Jeung Woon; Lee, Min Gyu; Kim, Ki Yong; Han, Jeung Whan

2017-01-01

Coagulation factors (II, VII, IX, X, and particularly XIa) remaining in high concentrations in intravenous immunoglobulin (IVIG) preparations can form thrombi, causing thromboembolic events, and in serious cases, result in death. Therefore, manufacturers of biological products must investigate the ability of their production processes to remove procoagulant activities. Previously, we were able to remove coagulation factors II, VII, IX, and X from our IVIG preparation through ethanol precipitation, but factor XIa, which plays an important role in thrombosis, remained in the intermediate products. Here, we used a chromatographic process using a new resin that binds with high capacity to IgG and removes procoagulant activities. The procoagulant activities were reduced to low levels as determined by the thrombin generation assay: <1.56 mIU/mL, chromogenic FXIa assay: <0.16 mIU/mL, non-activated partial thromboplastin time (NaPTT): >250 s, FXI/FXIa ELISA: <0.31 ng/mL. Even after spiking with FXIa at a concentration 32.5 times higher than the concentration in normal specimens, the procoagulant activities were below the detection limit (<0.31 ng/mL). These results demonstrate the ability of our manufacturing process to remove procoagulant activities to below the detection limit (except by NaPTT), suggesting a reduced risk of thromboembolic events that maybe potentially caused by our IVIG preparation. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

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

Almus, F.E.; Rao, L.V.; Fleck, R.A.

An umbilical vein model was designed in which washed vein segments are filled with a reaction mixture containing factor VIIa, Ca(+)+, and a substrate, either 3H-factor IX or 3H-factor X. The vein wall provides the tissue factor (TF) for factor VIIa/TF complexes that activate the substrates as measured by activation peptide release. The model was developed to study TF induced on venous endothelium in situ. However, unlike previous studies with TF expressed on cultured umbilical vein endothelial cells, factors IX and X were activated without first having to expose the vein wall to a perturbing stimulus. Histologic studies revealed thatmore » washing the vein and mixing the reaction mixture before subsampling had disrupted the endothelium. Immunostaining with anti-TF antibodies revealed no staining of endothelium but intense staining in extensions of Wharton's jelly penetrating fenestrations of the muscularis media of the vein. Thus, the model provided data on factor VIIa/TF formed, not on endothelium, but within the mucoid connective tissue of Wharton's jelly. It is known that factor VIIa/TF formed with TF in suspension or with TF expressed on the surface of cultured cells activates factor X more rapidly than factor IX. In contrast, in the umbilical vein model, when each substrate was present in an 88 nmol/L concentration, factors IX and X were activated at equivalent rates (mean activation rate for factor IX, 18.8 +/- 3.6 nmol/L/h; for factor X, 17.8 +/- 2.9 nmol/L/h; n = 9 paired vein segments). These data strengthen the evidence that factor VIIa/TF activation of factor IX represents a key initial reaction of coagulation in tissues. These results also show that data obtained with factor VIIa/TF complexes formed on the surface of cultured cells need not hold for factor VIIa/TF complexes formed in extracellular matrix.« less

Associations of coagulation factors IX and XI levels with incident coronary heart disease and ischemic stroke: the REGARDS study.

PubMed

Olson, N C; Cushman, M; Judd, S E; Kissela, B M; Safford, M M; Howard, G; Zakai, N A

2017-06-01

Essentials Coagulation factors (F) IX and XI have been implicated in cardiovascular disease (CVD) risk. We studied associations of FIX and FXI with incident coronary heart disease (CHD) and stroke. Higher FIX antigen was associated with incident CHD risk in blacks but not whites. Higher levels of FIX antigen may be a CHD risk factor among blacks. Background Recent studies have suggested the importance of coagulation factor IX and FXI in cardiovascular disease (CVD) risk. Objectives To determine whether basal levels of FIX or FXI antigen were associated with the risk of incident coronary heart disease (CHD) or ischemic stroke. Patients/Methods The REasons for Geographic And Racial Differences in Stroke (REGARDS) study recruited 30 239 participants across the contiguous USA between 2003 and 2007. In a case-cohort study within REGARDS, FIX and FXI antigen were measured in participants with incident CHD (n = 609), in participants with incident ischemic stroke (n = 538), and in a cohort random sample (n = 1038). Hazard ratios (HRs) for CHD and ischemic stroke risk were estimated with Cox models per standard deviation higher FIX or FXI level, adjusted for CVD risk factors. Results In models adjusting for CHD risk factors, higher FIX levels were associated with incident CHD risk (HR 1.19; 95% confidence interval [CI] 1.01-1.40) and the relationship of higher FXI levels was slightly weaker (HR 1.15; 95% CI 0.97-1.36). When stratified by race, the HR of FIX was higher in blacks (HR 1.39; 95% CI 1.10-1.75) than in whites (HR 1.06; 95% CI 0.86-1.31). After adjustment for stroke risk factors, there was no longer an association of FIX levels with ischemic stroke, whereas the association of FXI levels with ischemic stroke was slightly attenuated. Conclusions Higher FIX antigen levels were associated with incident CHD in blacks but not in whites. FIX levels may increase CHD risk among blacks. © 2017 International Society on Thrombosis and Haemostasis.

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.

In Vivo Bleeding Time and In Vitro Thrombelastography Measurements are Better Indicators of Dilutional Hypothermic Coagulopathy Than Prothrombin Time

DTIC Science & Technology

2007-06-01

of increased bruising, hematomas, and oozing from the recent surgical sites, or in massive hemorrhage from silent, pre-existing lesions such as peptic ... ulcers . Severe reduction of the vitamin K-dependent coagulation factors II, VII, IX, and X prolongs both PT and aPTT tests. Treatment with sodium

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

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.

Absence of in vitro Procoagulant Activity in Immunoglobulin Preparations due to Activated Coagulation Factors

PubMed Central

Oviedo, Adriana E.; Bernardi, María E.; Guglielmone, Hugo A.; Vitali, María S.

2015-01-01

Summary Background Immunoglobulin (IG) products, including intravenous (IVIG) or subcutaneous (SCIG) immunoglobulins are considered safe and effective for medical therapy; however, a sudden and unexpected increase in thromboembolic events (TE) after administration of certain batches of IVIG products has been attributed to the presence of activated coagulation factors, mainly factor XIa. Our aims were to examine the presence of enduring procoagulant activity during the manufacturing process of IGs, with special focus on monitoring factor XIa, and to evaluate the presence of in vitro procoagulant activity attributed to coagulation factors in different lots of IVIG and SCIG. Methods Samples of different steps of IG purification, 19 lots of IVIG and 9 of SCIG were analyzed and compared with 1 commercial preparation of IVIG and 2 of SCIG, respectively. Factors II, VII, IX, XI and XIa and non-activated partial thromboplastin time (NAPTT) were assayed. Results The levels of factors II, VII, IX, X and XI were non-quantifiable once fraction II had been re-dissolved and in all analyzed lots of IVIG and SCIG. The level of factor XIa at that point was under the detection limits of the assay, and NAPTT yielded values greater than the control during the purification process. In SCIG, we detected higher concentrations of factor XIa in the commercial products, which reached values up to 5 times higher than the average amounts found in the 9 batches produced by UNC-Hemoderivados. Factor XIa in commercial IVIG reached levels slightly higher than those of the 19 batches produced by UNC-Hemoderivados. Conclusion IVIG and SCIG manufactured by UNC-Hemoderivados showed a lack of thrombogenic potential, as demonstrated not only by the laboratory data obtained in this study but also by the absence of any reports of TE registered by the post marketing pharmacovigilance department. PMID:26733772

Platelet Glycoprotein lb-1X and Malignancy

DTIC Science & Technology

2010-09-01

supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation factors. This paradigm has been...a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib-IX have been identified, including...08-1-0576 TITLE: Platelet Glycoprotein lb-1X and Malignancy PRINCIPAL INVESTIGATOR: Dr. Jerry Ware

Labor and delivery in a patient with hemophilia B.

PubMed

Przkora, R; Euliano, T Y; Roussos-Ross, K; Zumberg, M; Robicsek, S A

2011-07-01

Hemophilia B is a rare X-linked disorder that may cause dramatic bleeding. Women account for only 3.2% of those clinically affected. The X-linked inheritance frequently delays the diagnosis in women and may expose the patient to an increased risk of adverse events. There is limited experience with these patients during labor and delivery. A 28-year-old primiparous woman with hemophilia B (bleeding phenotype) delivered a male infant by an unplanned cesarean delivery under general anesthesia following treatment with factor IX and normalization of her coagulation parameters, guided by thromboelastography. Postpartum vaginal bleeding required transfusion of two units of packed red blood cells. Factor IX supplementation continued for one week. Once diagnosed with hemophilia B, a multidisciplinary approach and advanced antenatal planning can increase the likelihood of a safe delivery. Neuraxial approaches and cesarean delivery are recommended only after normalization of the coagulation profile. The male fetus of a hemophilia A or B patient requires special attention. Operative vaginal delivery and invasive fetal monitoring should be avoided. Thromboelastography is an excellent technique to assess parturients with bleeding disorders or peripartum hemorrhage and may be underused. Copyright © 2011 Elsevier Ltd. All rights reserved.

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.

Liver-Directed Lentiviral Gene Therapy in a Dog Model of Hemophilia B

PubMed Central

Bartholomae, Cynthia C.; Volpin, Monica; Della Valle, Patrizia; Sanvito, Francesca; Sergi Sergi, Lucia; Gallina, Pierangela; Benedicenti, Fabrizio; Bellinger, Dwight; Raymer, Robin; Merricks, Elizabeth; Bellintani, Francesca; Martin, Samia; Doglioni, Claudio; D’Angelo, Armando; VandenDriessche, Thierry; Chuah, Marinee K.; Schmidt, Manfred; Nichols, Timothy; Montini, Eugenio; Naldini, Luigi

2017-01-01

We investigated the safety and efficacy of liver-directed gene therapy using lentiviral vectors in a large animal model of hemophilia B, and evaluated the risk of insertional mutagenesis in tumor-prone mouse models. We show that gene therapy using lentiviral vectors targeting expression of a canine factor IX transgene to hepatocytes was well-tolerated and provided stable long-term production of coagulation factor IX in dogs with hemophilia B. By exploiting three different mouse models designed to amplify the consequences of insertional mutagenesis, we show that no genotoxicity was detected with these lentiviral vectors. Our findings suggest that lentiviral vectors may be an attractive candidate for gene therapy targeted to the liver and may be useful for the treatment of hemophilia. PMID:25739762

Preparation of factor VII concentrate using CNBr-activated Sepharose 4B immunoaffinity chromatography

PubMed Central

Mousavi Hosseini, Kamran; Nasiri, Saleh

2015-01-01

Background: Factor VII concentrates are used in patients with congenital or acquired factor VII deficiency or treatment of hemophilia patients with inhibitors. In this research, immunoaffinity chromatography was used to purify factor VII from prothrombin complex (Prothrombin- Proconvertin-Stuart Factor-Antihemophilic Factor B or PPSB) which contains coagulation factors II, VII, IX and X. The aim of this study was to improve purity, safety and tolerability as a highly purified factor VII concentrate. Methods: PPSB was prepared using DEAE-Sephadex and was used as the starting material for purification of coagulation factor VII. Prothrombin complex was treated by solvent/detergent at 24°C for 6 h with constant stirring. The mixture of PPSB in the PBS buffer was filtered and then chromatographed using CNBr-activated Sepharose 4B coupled with specific antibody. Factors II, IX, VII, X and VIIa were assayed on the fractions. Fractions of 48-50 were pooled and lyophilized as a factor VII concentrate. Agarose gel electrophoresis was performed and Tween 80 was measured in the factor VII concentrate. Results: Specific activity of factor VII concentrate increased from 0.16 to 55.6 with a purificationfold of 347.5 and the amount of activated factor VII (FVIIa) was found higher than PPSB (4.4-fold). Results of electrophoresis on agarose gel indicated higher purity of Factor VII compared to PPSB; these finding revealed that factor VII migrated as alpha-2 proteins. In order to improve viral safety, solvent-detergent treatment was applied prior to further purification and nearly complete elimination of tween 80 (2 μg/ml). Conclusion: It was concluded that immuonoaffinity chromatography using CNBr-activated Sepharose 4B can be a suitable choice for large-scale production of factor VII concentrate with higher purity, safety and activated factor VII. PMID:26034723

Preparation of factor VII concentrate using CNBr-activated Sepharose 4B immunoaffinity chromatography.

PubMed

Mousavi Hosseini, Kamran; Nasiri, Saleh

2015-01-01

Factor VII concentrates are used in patients with congenital or acquired factor VII deficiency or treatment of hemophilia patients with inhibitors. In this research, immunoaffinity chromatography was used to purify factor VII from prothrombin complex (Prothrombin- Proconvertin-Stuart Factor-Antihemophilic Factor B or PPSB) which contains coagulation factors II, VII, IX and X. The aim of this study was to improve purity, safety and tolerability as a highly purified factor VII concentrate. PPSB was prepared using DEAE-Sephadex and was used as the starting material for purification of coagulation factor VII. Prothrombin complex was treated by solvent/detergent at 24°C for 6 h with constant stirring. The mixture of PPSB in the PBS buffer was filtered and then chromatographed using CNBr-activated Sepharose 4B coupled with specific antibody. Factors II, IX, VII, X and VIIa were assayed on the fractions. Fractions of 48-50 were pooled and lyophilized as a factor VII concentrate. Agarose gel electrophoresis was performed and Tween 80 was measured in the factor VII concentrate. Specific activity of factor VII concentrate increased from 0.16 to 55.6 with a purificationfold of 347.5 and the amount of activated factor VII (FVIIa) was found higher than PPSB (4.4-fold). RESULTS of electrophoresis on agarose gel indicated higher purity of Factor VII compared to PPSB; these finding revealed that factor VII migrated as alpha-2 proteins. In order to improve viral safety, solvent-detergent treatment was applied prior to further purification and nearly complete elimination of tween 80 (2 μg/ml). It was concluded that immuonoaffinity chromatography using CNBr-activated Sepharose 4B can be a suitable choice for large-scale production of factor VII concentrate with higher purity, safety and activated factor VII.

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.

An interactive mutation database for human coagulation factor IX provides novel insights into the phenotypes and genetics of hemophilia B.

PubMed

Rallapalli, P M; Kemball-Cook, G; Tuddenham, E G; Gomez, K; Perkins, S J

2013-07-01

Factor IX (FIX) is important in the coagulation cascade, being activated to FIXa on cleavage. Defects in the human F9 gene frequently lead to hemophilia B. To assess 1113 unique F9 mutations corresponding to 3721 patient entries in a new and up-to-date interactive web database alongside the FIXa protein structure. The mutations database was built using MySQL and structural analyses were based on a homology model for the human FIXa structure based on closely-related crystal structures. Mutations have been found in 336 (73%) out of 461 residues in FIX. There were 812 unique point mutations, 182 deletions, 54 polymorphisms, 39 insertions and 26 others that together comprise a total of 1113 unique variants. The 64 unique mild severity mutations in the mature protein with known circulating protein phenotypes include 15 (23%) quantitative type I mutations and 41 (64%) predominantly qualitative type II mutations. Inhibitors were described in 59 reports (1.6%) corresponding to 25 unique mutations. The interactive database provides insights into mechanisms of hemophilia B. Type II mutations are deduced to disrupt predominantly those structural regions involved with functional interactions. The interactive features of the database will assist in making judgments about patient management. © 2013 International Society on Thrombosis and Haemostasis.

Liver-directed lentiviral gene therapy in a dog model of hemophilia B.

PubMed

Cantore, Alessio; Ranzani, Marco; Bartholomae, Cynthia C; Volpin, Monica; Valle, Patrizia Della; Sanvito, Francesca; Sergi, Lucia Sergi; Gallina, Pierangela; Benedicenti, Fabrizio; Bellinger, Dwight; Raymer, Robin; Merricks, Elizabeth; Bellintani, Francesca; Martin, Samia; Doglioni, Claudio; D'Angelo, Armando; VandenDriessche, Thierry; Chuah, Marinee K; Schmidt, Manfred; Nichols, Timothy; Montini, Eugenio; Naldini, Luigi

2015-03-04

We investigated the efficacy of liver-directed gene therapy using lentiviral vectors in a large animal model of hemophilia B and evaluated the risk of insertional mutagenesis in tumor-prone mouse models. We showed that gene therapy using lentiviral vectors targeting the expression of a canine factor IX transgene in hepatocytes was well tolerated and provided a stable long-term production of coagulation factor IX in dogs with hemophilia B. By exploiting three different mouse models designed to amplify the consequences of insertional mutagenesis, we showed that no genotoxicity was detected with these lentiviral vectors. Our findings suggest that lentiviral vectors may be an attractive candidate for gene therapy targeted to the liver and may be potentially useful for the treatment of hemophilia. Copyright © 2015, American Association for the Advancement of Science.

[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.

Platelet Glycoprotein Ib-IX and Malignancy

DTIC Science & Technology

2010-09-01

provide a unique microenvironment supporting the accumulation of more platelets and the elaboration of a fibrin - rich network produced by coagulation...process and can initiate the formation of a platelet - rich thrombus by tethering the platelet to a thrombogenic surface. Several ligands binding to GP Ib... Platelet Glycoprotein Ib-IX and Malignancy PRINCIPAL INVESTIGATOR: Jerry Ware, Ph.D

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.

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.

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

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.

Characterization of IXINITY® (Trenonacog Alfa), a Recombinant Factor IX with Primary Sequence Corresponding to the Threonine-148 Polymorph

PubMed Central

Monroe, Dougald M.; Jenny, Richard J.; Van Cott, Kevin E.; Saward, Laura L.

2016-01-01

The goal of these studies was to extensively characterize the first recombinant FIX therapeutic corresponding to the threonine-148 (Thr-148) polymorph, IXINITY (trenonacog alfa [coagulation factor IX (recombinant)]). Gel electrophoresis, circular dichroism, and gel filtration were used to determine purity and confirm structure. Chromatographic and mass spectrometry techniques were used to identify and quantify posttranslational modifications. Activity was assessed as the ability to activate factor X (FX) both with and without factor VIIIa (FVIIIa) and in a standard clotting assay. All results were consistent across multiple lots. Trenonacog alfa migrated as a single band on Coomassie-stained gels; activity assays were normal and showed <0.002 IU of activated factor IX (FIXa) per IU of FIX. The molecule has >97%  γ-carboxylation and underwent the appropriate structural change upon binding calcium ions. Trenonacog alfa was activated normally with factor XIa (FXIa); once activated it bound to FVIIIa and FXa. When activated to FIXa, it was inhibited efficiently by antithrombin. Glycosylation patterns were similar to plasma-derived FIX with sialic acid content consistent with the literature reports of good pharmacokinetic performance. These studies have shown that trenonacog alfa is a highly pure product with a primary sequence and posttranslational modifications consistent with the common Thr-148 polymorphism of plasma-derived FIX. PMID:26997955

CRISPR/Cas9-mediated somatic correction of a novel coagulator factor IX gene mutation ameliorates hemophilia in mouse.

PubMed

Guan, Yuting; Ma, Yanlin; Li, Qi; Sun, Zhenliang; Ma, Lie; Wu, Lijuan; Wang, Liren; Zeng, Li; Shao, Yanjiao; Chen, Yuting; Ma, Ning; Lu, Wenqing; Hu, Kewen; Han, Honghui; Yu, Yanhong; Huang, Yuanhua; Liu, Mingyao; Li, Dali

2016-05-01

The X-linked genetic bleeding disorder caused by deficiency of coagulator factor IX, hemophilia B, is a disease ideally suited for gene therapy with genome editing technology. Here, we identify a family with hemophilia B carrying a novel mutation, Y371D, in the human F9 gene. The CRISPR/Cas9 system was used to generate distinct genetically modified mouse models and confirmed that the novel Y371D mutation resulted in a more severe hemophilia B phenotype than the previously identified Y371S mutation. To develop therapeutic strategies targeting this mutation, we subsequently compared naked DNA constructs versus adenoviral vectors to deliver Cas9 components targeting the F9 Y371D mutation in adult mice. After treatment, hemophilia B mice receiving naked DNA constructs exhibited correction of over 0.56% of F9 alleles in hepatocytes, which was sufficient to restore hemostasis. In contrast, the adenoviral delivery system resulted in a higher corrective efficiency but no therapeutic effects due to severe hepatic toxicity. Our studies suggest that CRISPR/Cas-mediated in situ genome editing could be a feasible therapeutic strategy for human hereditary diseases, although an efficient and clinically relevant delivery system is required for further clinical studies. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

Low cost industrial production of coagulation factor IX bioencapsulated in lettuce cells for oral tolerance induction in hemophilia B

PubMed Central

Su, Jin; Zhu, Liqing; Sherman, Alexandra; Wang, Xiaomei; Lin, Shina; Kamesh, Aditya; Norikane, Joey H.; Streatfield, Stephen J.; Herzog, Roland W.; Daniell, Henry

2015-01-01

Antibodies (inhibitors) developed by hemophilia B patients against coagulation factor IX (FIX) are challenging to eliminate because of anaphylaxis or nephrotic syndrome after continued infusion. To address this urgent unmet medical need, FIX fused with a transmucosal carrier (CTB) was produced in a commercial lettuce (Simpson Elite) cultivar using species specific chloroplast vectors regulated by endogenous psbA sequences. CTB-FIX (~1mg/g) in lyophilized cells was stable with proper folding, disulfide bonds and pentamer assembly when stored ~2 years at ambient temperature. Feeding lettuce cells to hemophilia B mice delivered CTB-FIX efficiently to the gut immune system, induced LAP+ regulatory T cells and suppressed inhibitor/IgE formation and anaphylaxis against FIX. Lyophilized cells enabled 10-fold dose escalation studies and successful induction of oral tolerance was observed in all tested doses. Induction of tolerance in such a broad dose range should enable oral delivery to patients of different age groups and diverse genetic background. Using Fraunhofer cGMP hydroponic system, ~870 kg fresh or 43.5 kg dry weight can be harvested per 1000 ft2 per annum yielding 24,000–36,000 doses for 20-kg pediatric patients, enabling first commercial development of an oral drug, addressing prohibitively expensive purification, cold storage/transportation and short shelf life of current protein drugs. PMID:26302233

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.

Key role of glycoprotein Ib/V/IX and von Willebrand factor in platelet activation-dependent fibrin formation at low shear flow

PubMed Central

Cosemans, Judith M. E. M.; Schols, Saskia E. M.; Stefanini, Lucia; de Witt, Susanne; Feijge, Marion A. H.; Hamulyák, Karly; Deckmyn, Hans; Bergmeier, Wolfgang

2011-01-01

A microscopic method was developed to study the role of platelets in fibrin formation. Perfusion of adhered platelets with plasma under coagulating conditions at a low shear rate (250−1) resulted in the assembly of a star-like fibrin network at the platelet surface. The focal fibrin formation on platelets was preceded by rises in cytosolic Ca2+, morphologic changes, and phosphatidylserine exposure. Fibrin formation was slightly affected by αIIbβ3 blockage, but it was greatly delayed and reduced by the following: inhibition of thrombin or platelet activation; interference in the binding of von Willebrand factor (VWF) to glycoprotein Ib/V/IX (GpIb-V-IX); plasma or blood from patients with type 1 von Willebrand disease; and plasma from mice deficient in VWF or the extracellular domain of GpIbα. In this process, the GpIb-binding A1 domain of VWF was similarly effective as full-length VWF. Prestimulation of platelets enhanced the formation of fibrin, which was abrogated by blockage of phosphatidylserine. Together, these results show that, in the presence of thrombin and low shear flow, VWF-induced activation of GpIb-V-IX triggers platelet procoagulant activity and anchorage of a star-like fibrin network. This process can be relevant in hemostasis and the manifestation of von Willebrand disease. PMID:21037087

[Case report. Phenprocoumon (Marcumar, Falithrom) as an unusual reason for coumarin poisoning in a dog].

PubMed

Lutze, G; Römhild, W; Elwert, J; Leppelt, J; Kutschmann, K

2003-01-01

Coumarin poisoning in dogs is not unusual and is in most cases caused by warfarin, a coumarin derivative which is used as a rodenticide. Competitive inhibition of vitamin K with an incomplete synthesis of the coagulation factors II, VII, IX and X can lead to a significant bleeding tendency. We observed a 3-year old male West Highland White Terrier with a reduced general condition and dyspnoea together with a massive haemothorax. Administration of vitamin K1 (3 mg/kg) led to a rapid improvement of the condition. Coagulation analysis revealed a prolonged activated recalcification time (ARCT), prothrombin time (PT) and aPTT with uncharacteristic thrombin time (TT); factor II, VII and X activities were reduced while factor V activity was normal, all of which are characteristic for coumarin poisoning. HPLC did not reveal the presence of warfarin but of phenoprocoumon, a drug used for thromboembolic prophylaxis in humans. This observation has not been described for dogs to date.

The effects of proton radiation on the prothrombin and partial thromboplastin times of irradiated ferrets

PubMed Central

Krigsfeld, Gabriel S.; Sanzari, Jenine K.; Kennedy, Ann R.

2013-01-01

Purpose To determine whether proton radiation affects coagulation. Material and methods Ferrets were exposed to solar particle event-like proton radiation at doses of 0, 25, 100, or 200 centigray (cGy), and dose rates of 50 cGy/minute (high dose rate or HDR) or 50 cGy/hour (low dose rate or LDR). Plasma was isolated from blood collected prior to radiation exposure and at 3–7 h post-radiation. Prothrombin time (PT) assays and activated partial thromboplastin time (aPTT) assays were performed as were mixing studies to determine the coagulation factors involved. Results HDR and LDR exposure led to statistically significant increases in PT values. It was determined that the HDR-induced increase in PT was due to Factor VII, while Factors II, V, and VII contributed to the LDR-induced increase in PT values. Only acute LDR exposure caused an increase in aPTT values, which remained elevated for 48 h post-irradiation (which was the latest time assayed in these studies). Mixing studies revealed that Factor IX contributed to the increased aPTT values. A majority of the animals exposed at the LDR had an International Normalized Ratio approaching or surpassing 2.0. Conclusions PT/aPTT assays resulted in increased clotting times due to different coagulation factors, indicating potential radiation-induced coagulopathy. PMID:22221163

Low cost industrial production of coagulation factor IX bioencapsulated in lettuce cells for oral tolerance induction in hemophilia B.

PubMed

Su, Jin; Zhu, Liqing; Sherman, Alexandra; Wang, Xiaomei; Lin, Shina; Kamesh, Aditya; Norikane, Joey H; Streatfield, Stephen J; Herzog, Roland W; Daniell, Henry

2015-11-01

Antibodies (inhibitors) developed by hemophilia B patients against coagulation factor IX (FIX) are challenging to eliminate because of anaphylaxis or nephrotic syndrome after continued infusion. To address this urgent unmet medical need, FIX fused with a transmucosal carrier (CTB) was produced in a commercial lettuce (Simpson Elite) cultivar using species specific chloroplast vectors regulated by endogenous psbA sequences. CTB-FIX (∼1 mg/g) in lyophilized cells was stable with proper folding, disulfide bonds and pentamer assembly when stored ∼2 years at ambient temperature. Feeding lettuce cells to hemophilia B mice delivered CTB-FIX efficiently to the gut immune system, induced LAP(+) regulatory T cells and suppressed inhibitor/IgE formation and anaphylaxis against FIX. Lyophilized cells enabled 10-fold dose escalation studies and successful induction of oral tolerance was observed in all tested doses. Induction of tolerance in such a broad dose range should enable oral delivery to patients of different age groups and diverse genetic background. Using Fraunhofer cGMP hydroponic system, ∼870 kg fresh or 43.5 kg dry weight can be harvested per 1000 ft(2) per annum yielding 24,000-36,000 doses for 20-kg pediatric patients, enabling first commercial development of an oral drug, addressing prohibitively expensive purification, cold storage/transportation and short shelf life of current protein drugs. Copyright © 2015 The Authors. Published by 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

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.

Genetic Correction and Hepatic Differentiation of Hemophilia B-specific Human Induced Pluripotent Stem Cells.

PubMed

He, Qiong; Wang, Hui-Hui; Cheng, Tao; Yuan, Wei-Ping; Ma, Yu-Po; Jiang, Yong-Ping; Ren, Zhi-Hua

2017-09-27

Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells (iPSCs) derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by sequencing the encoding area of human coagulation factor IX (F IX) gene. Genomic DNA was extracted from the iPSCs, and the primers were designed to amplify the eight exons of F IX. Next, the point mutation in those iPSCs was genetically corrected using CRISPR/Cas9 technology in the presence of a 129-nucleotide homologous repair template that contained two synonymous mutations. Then, top 8 potential off-target sites were subsequently analyzed using Sanger sequencing. Finally, the corrected clones were differentiated into hepatocyte-like cells, and the secretion of F IX was validated by immunocytochemistry and ELISA assay. Results The cell line bore a missense mutation in the 6 th coding exon (c.676 C>T) of F IX gene. Correction of the point mutation was achieved via CRISPR/Cas9 technology in situ with a high efficacy at about 22% (10/45) and no off-target effects detected in the corrected iPSC clones. F IX secretion, which was further visualized by immunocytochemistry and quantified by ELISA in vitro, reached about 6 ng/ml on day 21 of differentiation procedure. Conclusions Mutations in human disease-specific iPSCs could be precisely corrected by CRISPR/Cas9 technology, and corrected cells still maintained hepatic differentiation capability. Our findings might throw a light on iPSC-based personalized therapies in the clinical application, especially for hemophilia B.

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.

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.

Antithrombotic Effect of Antisense Factor XI Oligonucleotide Treatment in Primates

PubMed Central

Crosby, Jeffrey R.; Marzec, Ulla; Revenko, Alexey S.; Zhao, Chenguang; Gao, Dacao; Matafonov, Anton; Gailani, David; MacLeod, A. Robert; Tucker, Erik I.; Gruber, Andras; Hanson, Stephen R.; Monia, Brett P.

2013-01-01

Objective During coagulation, factor IX (FIX) is activated by two distinct mechanisms mediated by the active proteases of either factors VII (FVIIa) or XI (FXIa). Both coagulation factors may contribute to thrombosis; factor XI, however, plays only a limited role in the arrest of bleeding. Therefore, therapeutic targeting of FXI may produce an antithrombotic effect with relatively low hemostatic risk. Approach and Results We have reported that reducing FXI levels with FXI antisense oligonucleotides (ASOs) produces antithrombotic activity in mice, and that administration of FXI ASOs to primates decreases circulating FXI levels and activity in a dose- and time-dependent manner. Here we evaluated the relationship between FXI plasma levels and thrombogenicity in an established baboon model of thrombosis and hemostasis. In previous studies with this model, antibody-induced inhibition of FXI produced potent antithrombotic effects. In the present report, ASO-mediated reduction of FXI plasma levels by ≥50% resulted in a demonstrable and sustained antithrombotic effect without an increased risk of bleeding. Conclusion These results indicate that reducing FXI levels using ASOs is a promising alternative to direct FXI inhibition, and that targeting FXI may be potentially safer than conventional antithrombotic therapies that can markedly impair primary hemostasis. PMID:23559626

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.

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.

Accumulation of functional recombinant human coagulation factor IX in transgenic soybean seeds.

PubMed

Cunha, Nicolau B; Murad, André M; Ramos, Gustavo L; Maranhão, Andréia Q; Brígido, Marcelo M; Araújo, Ana Cláudia G; Lacorte, Cristiano; Aragão, Francisco J L; Covas, Dimas T; Fontes, Aparecida M; Souza, Gustavo H M F; Vianna, Giovanni R; Rech, Elíbio L

2011-08-01

The seed-based production of recombinant proteins is an efficient strategy to achieve the accumulation, correct folding, and increased stability of these recombinant proteins. Among potential plant molecular farming systems, soybean [Glycine max (L.) Merrill] is a viable option for the production of recombinant proteins due to its high protein content, known regulatory sequences, efficient gene transfer protocols, and a scalable production system under greenhouse conditions. We report here the expression and stable accumulation of human coagulation factor IX (hFIX) in transgenic soybean seeds. A biolistic process was utilised to co-introduce a plasmid carrying the hFIX gene under the transcriptional control of the α' subunit of a β-conglycinin seed-specific promoter and an α-Coixin signal peptide in soybean embryonic axes from mature seeds. The 56-kDa hFIX protein was expressed in the transgenic seeds at levels of up to 0.23% (0.8 g kg(-1) seed) of the total soluble seed protein as determined by an enzyme-linked immunosorbent assay (ELISA) and western blot. Ultrastructural immunocytochemistry assays indicated that the recombinant hFIX in seed cotyledonary cells was efficiently directed to protein storage vacuoles. Mass spectrometry characterisation confirmed the presence of the hFIX recombinant protein sequence. Protein extracts from transgenic seeds showed a blood-clotting activity of up to 1.4% of normal plasma. Our results demonstrate the correct processing and stable accumulation of functional hFIX in soybean seeds stored for 6 years under room temperature conditions (22 ± 2°C).

EGF domain of coagulation factor IX is conducive to exposure of phosphatidylserine.

PubMed

Hidai, Chiaki; Fujiwara, Yusuke; Kokubun, Shinichiro; Kitano, Hisataka

2017-04-01

Lipid rafts are an initiation site for many different signals. Recently, we reported that an EGF domain in activated coagulation factor IX (EGF-F9) increases lipid raft formation and accelerates cell migration. However, the detailed mechanism is not well understood. This study aimed to evaluate the effects of EGF-F9 on the cell membrane. A431 cells (derived from human squamous cell carcinoma) were treated with recombinant EGF-F9. Cells were immunocytochemically stained with probes for lipid rafts or phosphatidylserine (PS). After 3 min of treatment with EGF-F9, cholera toxin subunit B (CTxB) binding domains emerged at the adhesive tips of filopodia. Subsequently, CTxB staining was observed on the filopodial shaft. Finally, large clusters of CTxB domains were observed at the edge of cell bodies. Markers for lipid rafts, such as caveolin-1 and a GPI anchored protein, co-localized with CTxB. Staining with annexin V and XII revealed that PS was exposed at the tips of filopodia, translocated on filopodial shafts, and co-localized with CTxB at the rafts. Immunocytochemistry showed that scramblase-1 protein was present at the filopodial tips. Our data indicates that EGF-F9 accelerates PS exposure around the filopodial adhesion complex and induces clustering of lipid rafts in the cell body. PS exposure is thought to occur on cells undergoing apoptosis. Further study of the function of the EGF-F9 motif in mediating signal transduction is necessary because it is shared by a number of proteins. © 2017 International Federation for Cell Biology.

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.

Increased production of functional recombinant human clotting factor IX by baby hamster kidney cells engineered to overexpress VKORC1, the vitamin K 2,3-epoxide-reducing enzyme of the vitamin K cycle.

PubMed

Wajih, Nadeem; Hutson, Susan M; Owen, John; Wallin, Reidar

2005-09-09

Some recombinant vitamin K-dependent blood coagulation factors (factors VII, IX, and protein C) have become valuable pharmaceuticals in the treatment of bleeding complications and sepsis. Because of their vitamin K-dependent post-translational modification, their synthesis by eukaryotic cells is essential. The eukaryotic cell harbors a vitamin K-dependent gamma-carboxylation system that converts the proteins to gamma-carboxyglutamic acid-containing proteins. However, the system in eukaryotic cells has limited capacity, and cell lines overexpressing vitamin K-dependent clotting factors produce only a fraction of the recombinant proteins as fully gamma-carboxylated, physiologically competent proteins. In this work we have used recombinant human factor IX (r-hFIX)-producing baby hamster kidney (BHK) cells, engineered to stably overexpress various components of the gamma-carboxylation system of the cell, to determine whether increased production of functional r-hFIX can be accomplished. All BHK cell lines secreted r-hFIX into serum-free medium. Overexpression of gamma-carboxylase is shown to inhibit production of functional r-hFIX. On the other hand, cells overexpressing VKORC1, the reduced vitamin K cofactor-producing enzyme of the vitamin K-dependent gamma-carboxylation system, produced 2.9-fold more functional r-hFIX than control BHK cells. The data are consistent with the notion that VKORC1 is the rate-limiting step in the system and is a key regulatory protein in synthesis of active vitamin K-dependent proteins. The data suggest that overexpression of VKORC1 can be utilized for increased cellular production of recombinant vitamin K-dependent proteins.

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.

Capital and Operating Cost of Small Arsenic Removal System and their Most Frequent Maintenance Problems

EPA Science Inventory

This presentation will first summarize the capital and operating cost of treatment systems by type and size of the systems. The treatment systems include adsorptive media (AM) systems, iron removal (IR), coagulation/filtration (CF), ion exchange (IX) systems, and point-of-use rev...

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.

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

Determinants of the Thrombogenic Potential of Multiwalled Carbon Nanotubes

PubMed Central

Burke, Andrew; Singh, Ravi; Carroll, David L.; Owen, John; Kock, Nancy D.; D’Agostino, Ralph; Torti, Frank M.; Torti, Suzy V.

2011-01-01

Multiwalled carbon nanotubes (MWCNTs) are cylindrical tubes of graphitic carbon with unique physical and electrical properties. MWCNTs are being explored for a variety of diagnostic and therapeutic applications. Successful biomedical application of MWCNTs will require compatibility with normal circulatory components, including constituents of the hemostatic cascades. In this manuscript, we compare the thrombotic activity of MWCNTs in vitro and in vivo. We also assess the influence of functionalization of MWCNTs on thrombotic activity. In vitro, MWCNT activate the intrinsic pathway of coagulation as measured by activated partial thromboplastin time (aPTT) assays. Functionalization by amidation or carboxylation enhances this procoagulant activity. Mechanistic studies demonstrate that MWCNTs enhance propagation of the intrinsic pathway via a non-classical mechanism strongly dependent on factor IX. MWCNTs preferentially associate with factor IXa and may provide a platform for its activation. In addition to their effects on the coagulation cascade, MWCNTs activate platelets in vitro, with amidated MWCNTs exhibiting greater platelet activation than carboxylated or pristine MWCNTs. However, contrasting trends are obtained in vivo, where functionalization tends to diminish rather than enhance pro-coagulant activity. Thus, following systemic injection of MWCNTs in mice, pristine MWCNTs decreased platelet counts, increased vWF, and increased D-dimers. In contrast, carboxylated MWCNTS exhibited little procoagulant tendency in vivo, eliciting only a mild and transient decrease in platelets. Amidated MWCNTs elicited no statistically significant change in platelet count. Further, neither carboxylated nor amidated MWCNTs increased vWF or D-dimers in mouse plasma. We conclude that the pro-coagulant tendencies of MWCNTs observed in vitro are not necessarily recapitulated in vivo. Further, functionalization can markedly attenuate the procoagulant activity of MWCNTs in vivo. This work will inform the rational development of biocompatible MWCNTs for systemic delivery. PMID:21663954

Purification and characterization of an abnormal factor IX (Christmas factor) molecule. Factor IX Chapel Hill.

PubMed Central

Chung, K S; Madar, D A; Goldsmith, J C; Kingdon, H S; Roberts, H R

1978-01-01

Human Factor IX (Christmas factor) was isolated from the plasma of a patient with mild hemophilia B. The patient's plasma contained 5% Factor IX clotting activity but 100% Factor IX antigenic activity as determined by immunological assays, which included inhibitor neutralization and a radioimmunoassay for Factor IX. This abnormal Factor IX is called Factor IX Chapel Hill (Factor IXCH). Both normal Factor IX and Factor IXCH have tyrosine as the NH2-terminal amino acid. The two proteins have a similar molecular weight, a similar amino acid analysis, the same number of gamma-carboxyglutamic acid residues (10 gamma-carboxyglutamic acid residues), and a similar carbohydrate content. Both exist as a single-chain glycoprotein in plasma. The major difference between normal Factor IX and Factor IXCH is that the latter exhibits delayed activation to Factor IXa in the presence of Factor XIa and Ca2+. Thus, Factor IXCH differs from other previously described abnormal Factor IX molecules. Images PMID:711853

Age-related regulation of genes: slow homeostatic changes and age-dimension technology

NASA Astrophysics Data System (ADS)

Kurachi, Kotoku; Zhang, Kezhong; Huo, Jeffrey; Ameri, Afshin; Kuwahara, Mitsuhiro; Fontaine, Jean-Marc; Yamamoto, Kei; Kurachi, Sumiko

2002-11-01

Through systematic studies of pro- and anti-blood coagulation factors, we have determined molecular mechanisms involving two genetic elements, age-related stability element (ASE), GAGGAAG and age-related increase element (AIE), a unique stretch of dinucleotide repeats (AIE). ASE and AIE are essential for age-related patterns of stable and increased gene expression patterns, respectively. Such age-related gene regulatory mechanisms are also critical for explaining homeostasis in various physiological reactions as well as slow homeostatic changes in them. The age-related increase expression of the human factor IX (hFIX) gene requires the presence of both ASE and AIE, which apparently function additively. The anti-coagulant factor protein C (hPC) gene uses an ASE (CAGGAG) to produce age-related stable expression. Both ASE sequences (G/CAGAAG) share consensus sequence of the transcriptional factor PEA-3 element. No other similar sequences, including another PEA-3 consensus sequence, GAGGATG, function in conferring age-related gene regulation. The age-regulatory mechanisms involving ASE and AIE apparently function universally with different genes and across different animal species. These findings have led us to develop a new field of research and applications, which we named “age-dimension technology (ADT)”. ADT has exciting potential for modifying age-related expression of genes as well as associated physiological processes, and developing novel, more effective prophylaxis or treatments for age-related diseases.

Comparison of the behavior of normal factor IX and the factor IX Bm variant Hilo in the prothrombin time test using tissue factors from bovine, human, and rabbit sources.

PubMed

Lefkowitz, J B; Monroe, D M; Kasper, C K; Roberts, H R

1993-07-01

A subset of hemophilia B patients have a prolonged bovine-brain prothrombin time. These CRM+ patients are classified as having hemophilia Bm. The prolongation of the prothrombin time has been reported only with bovine brain (referred to as ox brain in some literature) as the source of thromboplastin; prothrombin times determined with thromboplastin from rabbit brain or human brain are not reported to be prolonged. Factor IX from a hemophilia Bm patient (factor IX Hilo) was isolated. The activity of factor IX Hilo was compared to that of normal factor IX in prothrombin time assays when the thromboplastin source was of bovine, rabbit, or human origin. Factor IX, either normal or Hilo, prolonged a prothrombin time regardless of the tissue factor source. However, unless thromboplastin was from a bovine source, this prolongation required high concentrations of factor IX. Further, factor IX normal was as effective as factor IX Hilo in prolonging the prothrombin time when rabbit or human thromboplastin was used. With bovine thromboplastin, factor IX Hilo was significantly better than factor IX normal at prolonging the prothrombin time. The amount of prolongation was dependent on the amount of factor IX Hilo added. In addition, the prolongation was dependent on the concentration of factor X present in the sample. The prothrombin time changed as much as 20 seconds when the factor X concentration was varied from 50% to 150% to normal (fixed concentration of factor IX Hilo). These results demonstrate the difficulty of classifying the severity of a hemophilia Bm patient based on the bovine brain prothrombin time unless both the factor IX and factor X concentrations are known.

Activated partial thromboplastin time derivative curves: helpful diagnostic tool in mixing test interpretation.

PubMed

Esmedere Eren, Sevim; Karakukcu, Cigdem; Ciraci, Mehmet Z; Ustundag, Yasemin; Karakukcu, Musa

2018-06-01

: The mixing test is used to evaluate whether prolonged activated partial thromboplastin time (APTT) is due to an inhibitor or a factor deficiency. The coagulation reaction is demonstrated with APTT derivative curves on the ACL TOP series. We aimed to determine the utility of APTT derivative curves in the mixing test process. The plasma of a patient was mixed with normal plasma in a 1 : 1 ratio and APTT assay was performed with SynthASil reagent. We observed roughness, biphasic and shoulder patterns in derivative curves during the mixing test. An extended laboratory investigation revealed a positive lupus anticoagulant, low factors XI and IX activities. Along with mixing test cut-off limits, we recommend analysing changes in APTT derivative curves to minimize erroneous interpretations of the mixing test. Derivative curves display either a normalizing pattern in factor deficiencies or an atypical pattern in the presence of lupus anticoagulant.

Vitamin K: an old vitamin in a new perspective.

PubMed

Gröber, U; Reichrath, J; Holick, M F; Kisters, K

2014-01-01

The topic of "Vitamin K" is currently booming on the health products market. Vitamin K is known to be important for blood coagulation. Current research increasingly indicates that the antihaemorrhagic vitamin has a considerable benefit in the prevention and treatment of bone and vascular disease. Vitamin K1 (phylloquinone) is more abundant in foods but less bioactive than the vitamin K2 menaquinones (especially MK-7, menaquinone-7). Vitamin K compounds undergo oxidation-reduction cycling within the endoplasmic reticulum membrane, donating electrons to activate specific proteins via enzymatic gamma-carboxylation of glutamate groups before being enzymatically reduced. Along with coagulation factors (II, VII, IX, X, and prothrombin), protein C and protein S, osteocalcin (OC), matrix Gla protein (MGP), periostin, Gas6, and other vitamin K-dependent (VKD) proteins support calcium homeostasis, inhibit vessel wall calcification, support endothelial integrity, facilitate bone mineralization, are involved in tissue renewal and cell growth control, and have numerous other effects. The following review describes the history of vitamin K, the physiological significance of the K vitamers, updates skeletal and cardiovascular benefits and important interactions with drugs.

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.

In silico designing of hyper-glycosylated analogs for the human coagulation factor IX.

PubMed

Ghasemi, Fahimeh; Zomorodipour, Alireza; Karkhane, Ali Asghar; Khorramizadeh, M Reza

2016-07-01

N-glycosylation is a process during which a glycan moiety attaches to the asparagine residue in the N-glycosylation consensus sequence (Asn-Xxx-Ser/Thr), where Xxx can be any amino acid except proline. Introduction of a new N-glycosylation site into a protein backbone leads to its hyper-glycosylation, and may improve the protein properties such as solubility, folding, stability, and secretion. Glyco-engineering is an approach to facilitate the hyper-glycosylation of recombinant proteins by application of the site-directed mutagenesis methods. In this regard, selection of a suitable location on the surface of a protein for introduction of a new N-glycosylation site is a main concern. In this work, a computational approach was conducted to select suitable location(s) for introducing new N-glycosylation sites into the human coagulation factor IX (hFIX). With this aim, the first 45 residues of mature hFIX were explored to find out suitable positions for introducing either Asn or Ser/Thr residues, to create new N-glycosylation site(s). Our exploration lead to detection of five potential positions, for hyper-glycosylation. For each suggested position, an analog was defined and subjected for N-glycosylation efficiency prediction. After generation of three-dimensional structures, by homology-based modeling, the five designed analogs were examined by molecular dynamic (MD) simulations, to predict their stability levels and probable structural distortions caused by amino acid substitutions, relative to the native counterpart. Three out of five suggested analogs, namely; E15T, K22N, and R37N, reached equilibration state with relatively constant Root Mean Square Deviation values. Additional analysis on the data obtained during MD simulations, lead us to conclude that, R37N is the only qualified analog with the most similar structure and dynamic behavior to that of the native counterpart, to be considered for further experimental investigations. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of flomoxef on blood coagulation and alcohol metabolism.

PubMed

Uchida, K; Matsubara, T

1991-01-01

The effect of flomoxef, a newly developed oxacephem antibiotic with an N-hydroxyethyltetrazolethiol (HTT) side chain, on blood coagulation and alcohol metabolism was compared with that of a series of cephalosporin antibiotics with N-methyltetrazolethiol (NMTT), thiadiazolethiol (TDT) or methylthiadiazolethiol (MTDT) side chains in position 3' of the cephalosporin nucleus known to cause hypoprothrombinemia and bleeding in patients who are malnourished, debilitated and/or of high age. A disulfiram-like effect caused by inhibition of aldehyde dehydrogenase was observed for NMTT-containing antibiotics. Studies were carried out on healthy volunteers and on rats. Eight-day treatment with 2 g flomoxef i.v. once or twice daily in five and six healthy male volunteers, respectively, did not cause any significant changes in prothrombin time (PT), coagulation factors II, VII, IX or X, in hepaplastin values or fibrinogen levels, activated partial thromboplastin time (APTT), platelet counts, bleeding time, or collagen- and ADP-induced platelet aggregation. Inhibition of vitamin K epoxide reductase was observed in rats treated with flomoxef, yet to a much lesser extent than observed for cephalosporins with NMTT, TDT or MTDT side chains. This defect was quickly normalized by vitamin K injection. There were no differences between oxacephem (1-O) and cephem (1-S) compounds with respect to effects on blood clotting and platelet aggregation. Flomoxef and its side chain HTT showed no influence on alcohol metbolism.

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.

DIFFERENCES IN IMMUNE RESPONSE MAY EXPLAIN LOWER SURVIVAL AMONG OLDER MEN WITH PNEUMONIA

PubMed Central

Reade, Michael C.; Yende, Sachin; D’Angelo, Gina; Kong, Lan; Kellum, John A; Barnato, Amber E.; Milbrandt, Eric B.; Dooley, Christopher; Mayr, Florian B.; Weissfeld, Lisa; Angus, Derek C.

2009-01-01

Objective Lower life expectancy in men is generally attributed to higher likelihood of risky behavior and because men develop chronic conditions earlier. If sex-related differences in survival are independent of pre-infection chronic health and health behavior, it would suggest that survival differences may occur due to sex differences in quality of care and biologic response to infection and these differences may contribute to sex differences in life expectancy. We assessed if sex-related survival difference following community-acquired pneumonia (CAP) is due to differences in clinical characteristics, quality of care, or immune response. Design, setting, and subjects Prospective observational cohort of 2183 subjects with CAP. Measurements and main results Mean age was 64.9 years. Compared to women, men were more likely to smoke and had more comorbidity. At emergency department presentation, men had different biomarker patterns, as evidenced by higher inflammation (tumor necrosis factor (TNF), interleukin (IL)-6, and IL-10) and fibrinolysis (D-dimer), and lower coagulation biomarkers (antithrombin-III and Factor IX) (P<0.05). Small differences in favor of men were seen in care quality, including antibiotic timing and compliance with American Thoracic Society guidelines. Men had lower survival at 30, 90, 365 days. The higher one-year mortality was not attenuated when adjusted for differences in demographics, smoking, resuscitation, insurance, and vaccination status, comorbidity, hospital characteristics, and illness severity (unadjusted hazard ratio (HR)=1.35, p=0.003 and adjusted HR=1.29, p=0.004). HR were no longer statistically significant when additionally adjusted for differences in ED concentrations of TNF, IL-6, IL-10, D-dimer, antithrombin-III, and Factor IX (adjusted HR=1.27, p=0.17). Patterns of biomarkers observed in men were associated with worse survival over one year. Conclusions Lower survival among men following CAP was not explained by differences in chronic diseases, health behaviors, and quality of care. Patterns of inflammatory, coagulation, and fibrinolysis biomarkers among men may explain reduced short and long-term survival. PMID:19325487

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.

Factor IX assay

MedlinePlus

... factor assay; Serum factor IX; Hemophilic factor B; Plasma thromboplastin component; PTC ... BJ. Factor IX (Christmas factor, hemophilic factor B, plasma thromboplastin component, PTC) - blood. In: Chernecky CC, Berger ...

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

In vitro characterization of high purity factor IX concentrates for the treatment of hemophilia B.

PubMed

Limentani, S A; Gowell, K P; Deitcher, S R

1995-04-01

This study employed sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis and immunoblotting to assess the purity of seven high purity factor IX concentrates: Aimafix (Aima), AlphaNine-SD (Alpha Therapeutic), Factor IX VHP (Biotransfusion), Immunine (Immuno), Mononine (Armour Pharmaceutical), Nanotiv (Kabi Pharmacia), and 9MC (Blood Products Laboratory). The mean specific activity of these products ranged from 68 U factor IX/mg (Aimafix) to 246 U factor IX/mg (Mononine). SDS-PAGE analysis showed that the highest purity product, Mononine, had a single contaminating band under non-reducing conditions. Two additional bands were detected when this product was analyzed under reducing conditions. All other products had multiple contaminating bands that were more apparent under reducing than non-reducing conditions. The immunoblot for factor IX showed a dominant factor IX band for all products. In addition, visible light chain of factor IX was detected for AlphaNine-SD, Factor IX VHP, Immunine, Mononine, Nanotiv, and 9MC, suggesting that the factor IX in these products had undergone partial activation to factor IXa. Another contaminating band was visible at 49,500 for all of the products except 9MC. In addition to this band, high molecular weight contaminants were apparent for some products, most notably AlphaNine-SD. The identity of these bands is unknown. Immunoblotting failed to demonstrate factor VII as a contaminant of any of the high purity products, although factor VIIa could be detected in some lots of Immunine, Nanotiv, and 9MC by a clot-based assay. Factor X contaminated Aimafix, AlphaNine-SD, Factor IX VHP, Immunine, Nanotiv, and 9MC, but activation products of factor X were not detected.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Treatment of hemophilia B: focus on recombinant factor IX

PubMed Central

Franchini, Massimo; Frattini, Francesco; Crestani, Silvia; Sissa, Cinzia; Bonfanti, Carlo

2013-01-01

Hemophilia B is a recessive X-linked bleeding disorder characterized by deficiency of the coagulation factor IX (FIX). In hemophilia B patients the severity of the bleeding phenotype is related to the degree of the FIX defect. Hemophilia B treatment has improved greatly in the last 20 years with the introduction first of plasma-derived and then of recombinant FIX concentrates. Replacement therapy may be administered through on-demand or prophylaxis regimens, but the latter treatment modality has been shown to be superior in prevention of hemophilic arthropathy and in improvement of patients’ quality of life. The purpose of this narrative review is to summarize the current knowledge on treatment strategies for hemophilia B, focusing on recombinant FIX products either clinically used or in development. There is only one rFIX product that is licensed to treat hemophilia B patients; from the analysis of the literature data presented in this review, the authors conclude that this rFIX product has demonstrated an excellent safety profile and excellent clinical efficacy for halting and preventing bleeds in hemophilia B patients. While prophylaxis has emerged as the best therapeutic strategy for such patients because of its ability to prevent hemophilic arthropathy and to improve patients’ quality of life, the pharmacokinetically tailored dosing of rFIX is another key point when planning hemophilia B treatment, as it allows optimization of the factor concentrate usage. Further clinical studies are needed to better assess the safety and efficacy (ie, the incidence of adverse reactions and inhibitor development) of newer rFIX products. PMID:23430394

Evaluation of factor IX deficiency by interdigitated electrode (IDE)

NASA Astrophysics Data System (ADS)

Gopinath, Subash C. B.; Hashim, Uda; Uda, M. N. A.

2017-03-01

Factor IX deficiency is the main cause of hemophilia A and B. This a severe excessive bleeding disorder that can even kill the patient if not treated with the right prescription of Factor IX hormone to stop the bleeding. The bleeding can be caused by an injury or even a sudden bleeding in some very rare cases. To find the Factor IX effectiveness and to understand the deficiency more carefully for the future of medicine, experiments are conducted to test the Factor IX using the Interdigitated Electrode (IDE) and gold Nanoparticle with the help of Nanoelectrical technology.

Vitamin K deficiency: a case report and review of current guidelines.

PubMed

Marchili, Maria Rosaria; Santoro, Elisa; Marchesi, Alessandra; Bianchi, Simona; Rotondi Aufiero, Lelia; Villani, Alberto

2018-03-14

Vitamin K, a fat soluble vitamin, is a necessary cofactor for the activation of coagulation factors II, VII, IX, X, and protein C and S. In neonatal period, vitamin K deficiency may lead to Vitamin K Deficiency Bleeding (VKDB). We present the case of a 2 months and 20 days Caucasian male, presented for bleeding from the injections sites of vaccines. At birth oral vitamin K prophylaxis was administered. Neonatal period was normal. He was exclusively breastfed and received a daily oral supplementation with 25 μg of vitamin K. A late onset vitamin K deficiency bleeding was suspected. Intravenous Vitamin K was administered with complete recovery. Nevertheless the oral prophylaxis, our case developed a VKDB: it is necessary to revise the current guidelines in order to standardize timing and dosage in different clinical conditions.

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.

[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.

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.

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

Sacubitril/Valsartan

PubMed Central

Cada, Dennis J.; Baker, Danial E.; Leonard, James

2015-01-01

Each month, subscribers to The Formulary Monograph Service receive 5 to 6 well-documented monographs on drugs that are newly released or are in late phase 3 trials. The monographs are targeted to Pharmacy & Therapeutics Committees. Subscribers also receive monthly 1-page summary monographs on agents that are useful for agendas and pharmacy/nursing in-services. A comprehensive target drug utilization evaluation/medication use evaluation (DUE/MUE) is also provided each month. With a subscription, the monographs are sent in print and are also available on-line. Monographs can be customized to meet the needs of a facility. A drug class review is now published monthly with The Formulary Monograph Service. Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. For more information about The Formulary Monograph Service, call The Formulary at 800-322-4349. The December 2015 monograph topics are rolapitant, insulin degludec, flibanserin, coagulation factor IX (recombinant), and grazoprevir/elbasvir. The Safety MUE is on rolapitant. PMID:27621510

The effects of age on inflammatory and coagulation-fibrinolysis response in patients hospitalized for pneumonia.

PubMed

Kale, Sachin; Yende, Sachin; Kong, Lan; Perkins, Amy; Kellum, John A; Newman, Anne B; Vallejo, Abbe N; Angus, Derek C

2010-11-04

To determine whether inflammatory and hemostasis response in patients hospitalized for pneumonia varies by age and whether these differences explain higher mortality in the elderly. In an observational cohort of subjects with community-acquired pneumonia (CAP) recruited from emergency departments (ED) in 28 hospitals, we divided subjects into 5 age groups (<50, 51-64, 65-74, 75-84, and ≥85). We measured circulating levels of inflammatory (TNF, IL-6, and IL-10), hemostasis (D-dimer, Factor IX, thrombin-antithrombin complex, antithrombin and plasminogen-activator inhibitor-1), and cell-surface markers (TLR-2, TLR-4, and HLA-DR) during the first week of hospitalization and at discharge and compared 90-day mortality. We used logistic regression to compare odds ratios (OR) for 90-day mortality between age groups, adjusting for differences in pre-infection factors alone and then additionally adjusting for immune markers. Of 2,183 subjects, 495, 444, 403, 583, and 258 subjects were <50, 51-64, 65-74, 75-84, and ≥85 years of age, respectively. Large age-related differences were observed in 90-day mortality (0.82% vs. 3.2% vs. 6.4% vs. 12.8% vs. 13.6%, p<0.01). No age-related differences in inflammatory and cell surface markers occurred during the first week. Older subjects had higher pro-coagulant markers on ED presentation and over first week (p ≤ 0.03), but these differences were modest (1.0-1.7-fold differences). Odds of death for older adults changed minimally in models incorporating differences in hemostasis and inflammatory markers (for subjects ≥ 85 compared to those <50, OR = 4.36, when adjusted for pre-infection factors and OR = 3.49 when additionally adjusted for hemostasis markers). At discharge, despite clinical recovery as evidenced by normal vital signs in >85% subjects, older subjects had modestly increased hemostasis markers and IL-6 levels (p<0.01). Modest age-related increases in coagulation response occur during hospitalization for CAP; however these differences do not explain the large differences in mortality. Despite clinical recovery, immune resolution may be delayed in older adults at discharge.

Development of a lectin binding assay to differentiate between recombinant and endogenous proteins in pharmacokinetic studies of protein-biopharmaceuticals.

PubMed

Weber, Alfred; Minibeck, Eva; Scheiflinger, Friedrich; Turecek, Peter L

2015-04-10

Human glycoproteins, expressed in hamster cell lines, show similar glycosylation patterns to naturally occurring human molecules except for a minute difference in the linkage of terminal sialic acid: both cell types lack α2,6-galactosyl-sialyltransferase, abundantly expressed in human hepatocytes and responsible for the α2,6-sialylation of circulating glycoproteins. This minute difference, which is currently not known to have any physiological relevance, was the basis for the selective measurement of recombinant glycoproteins in the presence of their endogenous counterparts. The assay is based on using the lectin Sambucus nigra agglutinin (SNA), selectively binding to α2,6-sialylated N-glycans. Using von Willebrand factor (VWF), factor IX (FIX), and factor VIIa (FVIIa), it was demonstrated that (i) the plasma-derived proteins, but not the corresponding recombinant proteins, specifically bind to SNA and (ii) this binding can be used to deplete the plasma-derived proteins. The feasibility of this approach was confirmed in spike-recovery studies for all three recombinant coagulation proteins in human plasma and for recombinant VWF (rVWF) in macaque plasma. Analysis of plasma samples from macaques after administration of recombinant and a plasma-derived VWF demonstrated the suitability and robustness of this approach. Data showed that rVWF could be selectively measured without changing the ELISAs and furthermore revealed the limitations of baseline adjustment using a single measurement of the predose concentration only. The SNA gel-based depletion procedure can easily be integrated in existing procedures as a specific sample pre-treatment step. While ELISA-based methods were used to measure the recombinant coagulation proteins in the supernatants obtained by depletion, this procedure is applicable for all biochemical analyses. Copyright © 2015 Elsevier B.V. All rights reserved.

Productive Recognition of Factor IX by Factor XIa Exosites Requires Disulfide Linkage between Heavy and Light Chains of Factor XIa*

PubMed Central

Marcinkiewicz, Mariola M.; Sinha, Dipali; Walsh, Peter N.

2012-01-01

In the intrinsic pathway of blood coagulation factor XIa (FXIa) activates factor IX (FIX) by cleaving the zymogen at Arg145-Ala146 and Arg180-Val181 bonds releasing an 11-kDa activation peptide. FXIa and its isolated light chain (FXIa-LC) cleave S-2366 at comparable rates, but FXIa-LC is a very poor activator of FIX, possibly because FIX undergoes allosteric modification on binding to an exosite on the heavy chain of FXIa (FXIa-HC) required for optimal cleavage rates of the two scissile bonds of FIX. However preincubation of FIX with a saturating concentration of isolated FXIa-HC did not result in any potentiation in the rate of FIX cleavage by FXIa-LC. Furthermore, if FIX binding via the heavy chain exosite of FXIa determines the affinity of the enzyme-substrate interaction, then the isolated FXIa-HC should inhibit the rate of FIX activation by depleting the substrate. However, whereas FXIa/S557A inhibited FIX activation of by FXIa, FXIa-HC did not. Therefore, we examined FIX binding to FXIa/S557A, FXIa-HC, FXIa-LC, FXIa/C362S/C482S, and FXIa/S557A/C362S/C482S. The heavy and light chains are disulfide-linked in FXIa/S557A but not in FXIa/C362S/C482S and FXIa/S557A/C362S/C482S. In an ELISA assay only FXI/S557A ligated FIX with high affinity. Partial reduction of FXIa/S557A to produce heavy and light chains resulted in decreased FIX binding, and this function was regained upon reformation of the disulfide linkage between the heavy and the light chains. We therefore conclude that substrate recognition by the FXIa exosite(s) requires disulfide-linked heavy and light chains. PMID:22207756

Hematologic risk factors for stroke in Saudi children.

PubMed

Salih, Mustafa A; Abdel-Gader, Abdel-Galil M; Al-Jarallah, Ahmed A; Kentab, Amal Y; Alorainy, Ibrahim A; Hassan, Hamdy H; Bahakim, Hassan M; Kurbaan, Khadija M; Zahraa, Jihad N; Murshid, Waleed R; El-Hazmi, Mohsen A; Khoja, Waleed A

2006-03-01

To explore the hematologic risk factors for stroke in a cohort of Saudi children. We evaluated children at the Division of Pediatric Neurology at King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, during the periods July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Investigations for suspected cases included neuroimaging, transcranial Doppler (TCD) for cases of sickle cell disease (SCD), and Duplex scan. Hemostatic assays included coagulation screening tests, tests of thrombin generation and fibrinolysis, coagulation inhibitors, and activated protein C resistance. During the study period, 104 Saudi children (aged one month to 12 years) with stroke were seen. The mean age of the cohort was 27.1 months (SD = 39.3 months) and median was 6 months. Ischemic strokes accounted for the majority of cases (76%). A major risk factor was identified in 93 of 104 cases of stroke (89.4%). Hematologic disorders were the most common (46.2%), followed by prothrombic disorders (31.7%); microcytic hypochromic anemia (26%); sickle cell disease (SCD), or SCbeta(0)-thalassemia, (11.5%), and factor IX deficiency (2.9%). Raised anticardiolipin antibodies (13/49, 26.5%) was the most frequent abnormality. Deficiencies of the natural anticoagulants (protein S, protein C and antithrombin III) were as follows: protein S (15/70, 21.4%); protein C (15/70, 21.4%) and combined deficiency of 2 or more inhibitors (9/70, 12.9%). Activated protein C resistance has not been detected. Contrary to the findings of previous studies from Saudi Arabia, SCD is a common risk factor and is severe, as it resulted in multiple strokes. Moyamoya syndrome was diagnosed in 2 patients with SCD, one of whom had revascularization surgery (encephaloduroarteriosynangiosis). Assessment of children with SCD at risk of stroke was helped by the introduction of TCD followed by neuroimaging, using MRI and magnetic resonance angiography. The study strongly highlights the importance of prothrombotic disorders and the severe phenotype of SCD as risk factors for stroke in Saudi children.

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

Red blood cell-derived microparticles isolated from blood units initiate and propagate thrombin generation.

PubMed

Rubin, Olivier; Delobel, Julien; Prudent, Michel; Lion, Niels; Kohl, Kid; Tucker, Erik I; Tissot, Jean-Daniel; Angelillo-Scherrer, Anne

2013-08-01

Red blood cell-derived microparticles (RMPs) are small phospholipid vesicles shed from RBCs in blood units, where they accumulate during storage. Because microparticles are bioactive, it could be suggested that RMPs are mediators of posttransfusion complications or, on the contrary, constitute a potential hemostatic agent. This study was performed to establish the impact on coagulation of RMPs isolated from blood units. Using calibrated automated thrombography, we investigated whether RMPs affect thrombin generation (TG) in plasma. We found that RMPs were not only able to increase TG in plasma in the presence of a low exogenous tissue factor (TF) concentration, but also to initiate TG in plasma in absence of exogenous TF. TG induced by RMPs in the absence of exogenous TF was neither affected by the presence of blocking anti-TF nor by the absence of Factor (F)VII. It was significantly reduced in plasma deficient in FVIII or F IX and abolished in FII-, FV-, FX-, or FXI-deficient plasma. TG was also totally abolished when anti-XI 01A6 was added in the sample. Finally, neither Western blotting, flow cytometry, nor immunogold labeling allowed the detection of traces of TF antigen. In addition, RMPs did not comprise polyphosphate, an important modulator of coagulation. Taken together, our data show that RMPs have FXI-dependent procoagulant properties and are able to initiate and propagate TG. The anionic surface of RMPs might be the site of FXI-mediated TG amplification and intrinsic tenase and prothrombinase complex assembly. © 2012 American Association of Blood Banks.

Two distinct forms of Factor VIII coagulant protein in human plasma. Cleavage by thrombin, and differences in coagulant activity and association with von Willebrand factor.

PubMed Central

Weinstein, M J; Chute, L E

1984-01-01

We have characterized Factor VIII coagulant protein, present in normal human plasma, that reacts with a specific human 125I-labeled anti-human VIII:C antigen Fab antibody fragment. Two major Factor VIII coagulant antigen populations were present. The first, approximately 85% of the total antigen, was bound to von Willebrand factor and when tested in a standard one-stage assay had Factor VIII coagulant activity. The second antigenic population, eluting near fibrinogen when plasma was gel filtered, was not bound to von Willebrand protein, did not have Factor VIII coagulant activity unless activated, but did block anti-VIII:C Fab neutralization of clotting activity. The two antigenic populations were separable by cryoprecipitation and agarose gel electrophoresis. Although the two antigenic populations differed in their Factor VIII coagulant activity and in their binding to von Willebrand factor, the principal member of both populations is of mol wt 2.4 X 10(5). Both antigens, when proteolyzed by thrombin, were quickly converted to a 1 X 10(5)-mol wt form in association with the appearance of VIII:C activity. The 1 X 10(5)-mol wt antigen was further slowly degraded to an 8 X 10(4)-mol wt form while Factor VIII coagulant activity declined. These results demonstrate the presence of an inactive Factor VIII coagulant protein in plasma, not associated with von Willebrand factor, that can react with thrombin to yield Factor VIII coagulant activity. Images PMID:6421875

Warfarin hypersensitivity due to gluten-sensitive enteropathy: a case study.

PubMed

Kwolek, Sara; Deming, Paula

2012-01-01

A 53 year old female who was maintained on long-term warfarin therapy due to history of pulmonary embolism, repeatedly presents with an abnormally prolonged Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT). After many asymptomatic episodes were corrected with Vitamin K therapy to temporarily reverse the effects of the warfarin, the cause of the apparent coagulopathy was further investigated. Factor Activity Assays of the common pathway factors II, IX, and X all revealed critically low values; below the threshold even a loading dose of warfarin is typically capable of eliciting. The patient tested strongly positive for Tissue Transglutaminase IgA, which is highly suggestive of a gluten-sensitive enteropathy. One effect of this condition is malabsorption due to flattened intestinal villi. The patient was determined to have an acquired vitamin K deficiency secondary to gluten-sensitive enteropathy. Her condition was exacerbated by the long-term warfarin therapy, resulting in the prolonged PT and PTT. The patient was treated with vitamin K therapy, which reversed the deficiency and corrected her abnormal coagulation results.

Measuring factor IX activity of nonacog beta pegol with commercially available one-stage clotting and chromogenic assay kits: a two-center study.

PubMed

Bowyer, A E; Hillarp, A; Ezban, M; Persson, P; Kitchen, S

2016-07-01

Essentials Validated assays are required to precisely measure factor IX (FIX) activity in FIX products. N9-GP and two other FIX products were assessed in various coagulation assay systems at two sites. Large variations in FIX activity measurements were observed for N9-GP using some assays. One-stage and chromogenic assays accurately measuring FIX activity for N9-GP were identified. Background Measurement of factor IX activity (FIX:C) with activated partial thromboplastin time-based one-stage clotting assays is associated with a large degree of interlaboratory variation in samples containing glycoPEGylated recombinant FIX (rFIX), i.e. nonacog beta pegol (N9-GP). Validation and qualification of specific assays and conditions are necessary for the accurate assessment of FIX:C in samples containing N9-GP. Objectives To assess the accuracy of various one-stage clotting and chromogenic assays for measuring FIX:C in samples containing N9-GP as compared with samples containing rFIX or plasma-derived FIX (pdFIX) across two laboratory sites. Methods FIX:C, in severe hemophilia B plasma spiked with a range of concentrations (from very low, i.e. 0.03 IU mL(-1) , to high, i.e. 0.90 IU mL(-1) ) of N9-GP, rFIX (BeneFIX), and pdFIX (Mononine), was determined at two laboratory sites with 10 commercially available one-stage clotting assays and two chromogenic FIX:C assays. Assays were performed with a plasma calibrator and different analyzers. Results A high degree of variation in FIX:C measurement was observed for one-stage clotting assays for N9-GP as compared with rFIX or pdFIX. Acceptable N9-GP recovery was observed in the low-concentration to high-concentration samples tested with one-stage clotting assays using SynthAFax or DG Synth, or with chromogenic FIX:C assays. Similar patterns of FIX:C measurement were observed at both laboratory sites, with minor differences probably being attributable to the use of different analyzers. Conclusions These results suggest that, of the reagents tested, FIX:C in N9-GP-containing plasma samples can be most accurately measured with one-stage clotting assays using SynthAFax or DG Synth, or with chromogenic FIX:C assays. © 2016 International Society on Thrombosis and Haemostasis.

Gadolinium and 5-Aminolevulinic Acid-induced Protoporphyrin IX Levels in Human Gliomas: An Ex Vivo Quantitative Study to Correlate Protoporphyrin IX Levels and Blood-Brain Barrier Breakdown

PubMed Central

Valdés, Pablo A.; Moses, Ziev B.; Kim, Anthony; Belden, Clifford J.; Wilson, Brian C.; Paulsen, Keith D.; Roberts, David W.; Harris, Brent T.

2012-01-01

In recent years, 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence guidance has been used as a surgical adjunct to improve the extent of resection of gliomas. Exogenous administration of ALA prior to surgery leads to the accumulation of red fluorescent PpIX in tumor tissue that the surgeon can visualize and thereby discriminate between normal and tumor tissue. Selective accumulation of PpIX has been linked to numerous factors, of which blood-brain barrier (BBB) breakdown has been suggested to be a key factor. To test the hypothesis that PpIX concentration (CPpIX) positively correlates with gadolinium (Gd) concentrations (CGd), we performed ex vivo measurements of PpIX and of Gd using Inductively-Coupled Plasma Mass Spectrometry (ICP-MS) the latter as a quantitative biomarker of BBB breakdown; this was corroborated with immunohistochemistry of microvascular density in surgical biopsies of patients undergoing fluorescence guided surgery for glioma .We found positive correlations between CPpIX and CGd (r = 0.58, p < 0.0001), and between CPpIX and microvascular density (r = 0.55, p < 0.0001), suggesting a significant, yet limited association between BBB breakdown and ALA-induced PpIX fluorescence. To our knowledge, this is the first time that Gd measurements by ICP-MS have been used in human gliomas. PMID:22878664

Coagulation Factor Tests

MedlinePlus

... your coagulation factors. Coagulation factors are known by Roman numerals (I, II VIII, etc.) or by name ( ... need this test if you have a family history of bleeding disorders. Most bleeding disorders are inherited . ...

Trenonacog alfa for prophylaxis, on-demand and perioperative management of hemophilia B.

PubMed

Brennan, Yvonne; Curnow, Jennifer; Favaloro, Emmanuel J

2018-01-01

Current treatment for hemophilia B involves replacing the missing coagulation factor IX (FIX) with either plasma-derived or recombinant (r) FIX. Trenonacog alfa is the third normal half-life rFIX that has been granted FDA approval. Area covered: In this review, the authors examine trenonacog alfa for the treatment of hemophilia B including prophylaxis, on-demand and perioperative hemostasis. They compare the PK profile to nonacog alfa and evaluate the drug's efficacy and safety from published studies. Expert opinion: Trenonacog alfa appears to be an effective and safe treatment option for patients with hemophilia B with a PK profile similar to that of nonacog alfa. Despite the advent of extended half-life rFIX and other novel therapeutic approaches, normal half-life rFIX products, including trenonacog alfa, are likely to continue to have a place in hemophilia B treatment for at least the immediate future while the new landscape takes shape, particularly in countries that cannot afford the newer treatments.

Intraoperative Changes in Blood Coagulation and Thrombelastographic Monitoring in Liver Transplantation

PubMed Central

Kang, Yoo Goo; Martin, Douglas J.; Marquez, Jose; Lewis, Jessica H.; Bontempo, Franklin A.; Shaw, Byers W.; Starzl, Thomas E.; Winter, Peter M.

2010-01-01

The blood coagulation system of 66 consecutive patients undergoing consecutive liver transplantations was monitored by thrombelastograph and analytic coagulation profile. A poor preoperative coagulation state, decrease in levels of coagulation factors, progressive fibrinolysis, and whole blood clot lysis were observed during the preanhepatic and anhepatic stages of surgery. A further general decrease in coagulation factors and platelets, activation of fibrinolysis, and abrupt decrease in levels of factors V and VIII occurred before and with reperfusion of the homograft. Recovery of blood coagulability began 30–60 min after reperfusion of the graft liver, and coagulability had returned toward baseline values 2 hr after reperfusion. A positive correlation was shown between the variables of thrombelastography and those of the coagulation profile. Thrombelastography was shown to be a reliable and rapid monitoring system. Its use was associated with a 33% reduction of blood and fluid infusion volume, whereas blood coagulability was maintained without an increase in the number of blood product donors. PMID:3896028

Patient Management with Metallic Valve Prosthesis during Pregnancy and Postpartum Period.

PubMed

Garcez, Juliane Dantas Seabra; Rosa, Vitor Emer Egypto; Lopes, Antonio Sergio de Santis Andrade; Accorsi, Tarso Augusto Duenhas; Fernandes, João Ricardo Cordeiro; Pomerantzeff, Pablo Maria; Avila, Walkiria Samuel; Tarasoutchi, Flavio

2015-10-01

Prosthetic thrombosis is a rare complication, but it has high mortality and morbidity. Young women of childbearing age that have prosthetic heart valves are at increased risk of thrombosis during pregnancy due to changes in coagulation factors. Anticoagulation with adequate control and frequent follow-up if pregnancy occurs must be performed in order to prevent complications related to anticoagulant use. Surgery remains the treatment of choice for prosthetic heart valve thrombosis in most clinical conditions. Patients with metallic prosthetic valves have an estimated 5% risk of thrombosis during pregnancy and maternal mortality of 1.5% related to the event. Anticoagulation with vitamin K antagonists during pregnancy is related to varying degrees of complications at each stage of the pregnancy and postpartum periods. Warfarin sodium crosses the placental barrier and when used in the first trimester of pregnancy is a teratogenic agent, causing 1-3% of malformations characterized by fetal warfarin syndrome and also constitutes a major cause of miscarriage in 10-30% of cases. In the third trimester and at delivery, the use of warfarin is associated with maternal and neonatal bleeding in approximately 5 to 15% of cases, respectively. On the other hand, inadequate anticoagulation, including the suspension of the oral anticoagulants aiming at fetal protection, carries a maternal risk of about 25% of metallic prosthesis thrombosis, particularly in the mitral valve. This fact is also due to the state of maternal hypercoagulability with activation of coagulation factors V, VI, VII, IX, X, platelet activity and fibrinogen synthesis, and decrease in protein S levels. The Registry of Pregnancy and Cardiac Disease (ROPAC), assessing 212 pregnant women with metal prosthesis, showed that prosthesis thrombosis occurred in 10 (4.7%) patients and maternal hemorrhage in 23.1%, concluding that only 58% of patients with metallic prosthesis had a complication-free pregnancy.

Gene therapy in an era of emerging treatment options for hemophilia B.

PubMed

Monahan, P E

2015-06-01

Factor IX deficiency (hemophilia B) is less common than factor VIII deficiency (hemophilia A), and innovations in therapy for hemophilia B have generally lagged behind those for hemophilia A. Recently, the first sustained correction of the hemophilia bleeding phenotype by clotting factor gene therapy has been described using recombinant adeno-associated virus (AAV) to deliver factor IX. Despite this success, many individuals with hemophilia B, including children, men with active hepatitis, and individuals who have pre-existing natural immunity to AAV, are not eligible for the current iteration of hemophilia B gene therapy. In addition, recent advances in recombinant factor IX protein engineering have led some hemophilia treaters to reconsider the urgency of genetic cure. Current clinical and preclinical approaches to advancing AAV-based and alternative approaches to factor IX gene therapy are considered in the context of current demographics and treatment of the hemophilia B population. © 2015 International Society on Thrombosis and Haemostasis.

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.

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.

Finding the optimal dose of vitamin K1 to treat vitamin K deficiency and to avoid anaphylactoid reactions.

PubMed

Mi, Yan-Ni; Ping, Na-Na; Li, Bo; Xiao, Xue; Zhu, Yan-Bing; Cao, Lei; Ren, Jian-Kang; Cao, Yong-Xiao

2017-10-01

Vitamin K1 injection induces severe dose-related anaphylactoid reactions and overdose for the treatment of vitamin K deficiency. We aimed to find an optimal and small dose of vitamin K1 injection to treat vitamin K deficiency and avoid anaphylactoid reactions in animal. Rats were administered a vitamin K-deficient diet and gentamicin to establish vitamin K deficiency model. Behaviour tests were performed in beagle dogs to observe anaphylactoid reactions. The results showed an increased protein induced by vitamin K absence or antagonist II (PIVKA-II) levels, a prolonging of prothrombin time (PT) and activated partial thromboplastin time (APTT) and a decrease in vitamin K-dependent coagulation factor (F) II, VII, IX and X activities in the model group. In vitamin K1 0.01 mg/kg group, the liver vitamin K1 levels increased fivefold and the liver vitamin K2 levels increased to the normal amount. Coagulation markers PT, APTT, FVII and FIX activities returned to normal. Both in the 0.1 and 1.0 mg/kg vitamin K1 groups, coagulation functions completely returned to normal. Moreover, the amount of liver vitamin K1 was 40 (0.1 mg/kg) or 100 (1.0 mg/kg) times as in normal. Vitamin K2 was about 4 (0.1 mg/kg) or 5 (1.0 mg/kg) times as the normal amount. There was no obvious anaphylactoid symptom in dogs with the dose of 0.03 mg/kg, which is equivalent to the dose of 0.01 mg/kg in rats. These results demonstrated that a small dose of vitamin K1 is effective to improve vitamin K deficiency and to prevent anaphylactoid reactions, simultaneously. © 2017 Société Française de Pharmacologie et de Thérapeutique.

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.

Prognostic Relevance of the Expression of CA IX, GLUT-1, and VEGF in Ovarian Epithelial Cancers

PubMed Central

Kim, Kyungbin; Park, Won Young; Kim, Jee Yeon; Sol, Mee Young; Shin, Dong Hun; Park, Do Youn; Lee, Chang Hun; Lee, Jeong Hee

2012-01-01

Background Tumor hypoxia is associated with malignant progression and treatment resistance. Hypoxia-related factors, such as carbonic anhydrase IX (CA IX), glucose transporter-1 (GLUT-1), and vascular endothelial growth factor (VEGF) permit tumor cell adaptation to hypoxia. We attempted to elucidate the correlation of these markers with variable clinicopathological factors and overall prognosis. Methods Immunohistochemistry for CA IX, GLUT-1, and VEGF was performed on formalin-fixed, paraffin-embedded tissues from 125 cases of ovarian epithelial cancer (OEC). Results CA IX expression was significantly associated with an endometrioid and mucinous histology, nuclear grade, tumor necrosis, and mitosis. GLUT-1 expression was associated with tumor necrosis and mitosis. VEGF expression was correlated only with disease recurrence. Expression of each marker was not significant in terms of overall survival in OECs; however, there was a significant correlation between poor overall survival rate and high coexpression of these markers. Conclusions The present study suggests that it is questionable whether CA IX, GLUT-1, or VEGF can be used alone as independent prognostic factors in OECs. Using at least two markers helps to predict patient outcomes in total OECs. Moreover, the inhibition of two target gene combinations might prove to be a novel anticancer therapy. PMID:23323103

The role of hyperthyroidism as the predisposing factor for superior sagittal sinus thrombosis.

PubMed

Hwang, Jong-Uk; Kwon, Ki-Young; Hur, Jin-Woo; Lee, Jong-Won; Lee, Hyun-Koo

2012-09-01

Superior sagittal sinus thrombosis (SSST) is an uncommon cause of stroke, whose symptoms and clinical course are highly variable. It is frequently associated with a variety of hypercoagulable states. Coagulation abnormalities are commonly seen in patients with hyperthyroidism. To the best of our knowledge, there are few reports on the association between hyperthyroidism and cerebral venous thrombosis. We report on a 31-year-old male patient with a six-year history of hyperthyroidism who developed seizure and mental deterioration. Findings on brain computed tomography (CT) showed multiple hemorrhages in the subcortical area of both middle frontal gyrus and cerebral digital subtraction angiography (DSA) showed irregular intra-luminal filling defects of the superior sagittal sinus. These findings were consistent with hemorrhagic transformation of SSST. Findings on clinical laboratory tests were consistent with hyperthyroidism. In addition, our patient also showed high activity of factors IX and XI. The patient received treatment with oral anticoagulant and prophylthiouracil. His symptoms showed complete improvement. A follow-up cerebral angiography four weeks after treatment showed a recanalization of the SSS. In conclusion, findings of our case indicate that hypercoagulability may contribute to development of SSST in a patient with hyperthyroidism.

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.

Factor IX expression in skeletal muscle of a severe hemophilia B patient 10 years after AAV-mediated gene transfer.

PubMed

Buchlis, George; Podsakoff, Gregory M; Radu, Antonetta; Hawk, Sarah M; Flake, Alan W; Mingozzi, Federico; High, Katherine A

2012-03-29

In previous work we transferred a human factor IX-encoding adeno-associated viral vector (AAV) into skeletal muscle of men with severe hemophilia B. Biopsy of injected muscle up to 1 year after vector injection showed evidence of gene transfer by Southern blot and of protein expression by IHC and immunofluorescent staining. Although the procedure appeared safe, circulating F.IX levels remained subtherapeutic (< 1%). Recently, we obtained muscle tissue from a subject injected 10 years earlier who died of causes unrelated to gene transfer. Using Western blot, IHC, and immunofluorescent staining, we show persistent factor IX expression in injected muscle tissue. F.IX transcripts were detected in injected skeletal muscle using RT-PCR, and isolated whole genomic DNA tested positive for the presence of the transferred AAV vector sequence. This is the longest reported transgene expression to date from a parenterally administered AAV vector, with broad implications for the future of muscle-directed gene transfer.

Successful transduction of liver in hemophilia by AAV-Factor IX and limitations imposed by the host immune response.

PubMed

Manno, Catherine S; Pierce, Glenn F; Arruda, Valder R; Glader, Bertil; Ragni, Margaret; Rasko, John J; Rasko, John; Ozelo, Margareth C; Hoots, Keith; Blatt, Philip; Konkle, Barbara; Dake, Michael; Kaye, Robin; Razavi, Mahmood; Zajko, Albert; Zehnder, James; Rustagi, Pradip K; Nakai, Hiroyuki; Chew, Amy; Leonard, Debra; Wright, J Fraser; Lessard, Ruth R; Sommer, Jürg M; Tigges, Michael; Sabatino, Denise; Luk, Alvin; Jiang, Haiyan; Mingozzi, Federico; Couto, Linda; Ertl, Hildegund C; High, Katherine A; Kay, Mark A

2006-03-01

We have previously shown that a single portal vein infusion of a recombinant adeno-associated viral vector (rAAV) expressing canine Factor IX (F.IX) resulted in long-term expression of therapeutic levels of F.IX in dogs with severe hemophilia B. We carried out a phase 1/2 dose-escalation clinical study to extend this approach to humans with severe hemophilia B. rAAV-2 vector expressing human F.IX was infused through the hepatic artery into seven subjects. The data show that: (i) vector infusion at doses up to 2 x 10(12) vg/kg was not associated with acute or long-lasting toxicity; (ii) therapeutic levels of F.IX were achieved at the highest dose tested; (iii) duration of expression at therapeutic levels was limited to a period of approximately 8 weeks; (iv) a gradual decline in F.IX was accompanied by a transient asymptomatic elevation of liver transaminases that resolved without treatment. Further studies suggested that destruction of transduced hepatocytes by cell-mediated immunity targeting antigens of the AAV capsid caused both the decline in F.IX and the transient transaminitis. We conclude that rAAV-2 vectors can transduce human hepatocytes in vivo to result in therapeutically relevant levels of F.IX, but that future studies in humans may require immunomodulation to achieve long-term expression.

Factor IX[sub Madrid 2]: A deletion/insertion in Facotr IX gene which abolishes the sequence of the donor junction at the exon IV-intron d splice site

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

Solera, J.; Magallon, M.; Martin-Villar, J.

1992-02-01

DNA from a patient with severe hemophilia B was evaluated by RFLP analysis, producing results which suggested the existence of a partial deletion within the factor IX gene. The deletion was further localized and characterized by PCR amplification and sequencing. The altered allele has a 4,442-bp deletion which removes both the donor splice site located at the 5[prime] end of intron d and the two last coding nucleotides located at the 3[prime] end of exon IV in the normal factor IX gene; this fragment has been inserted in inverted orientation. Two homologous sequences have been discovered at the ends ofmore » the deleted DNA fragment.« less

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.

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.

Gypenoside IX Suppresses p38 MAPK/Akt/NFκB Signaling Pathway Activation and Inflammatory Responses in Astrocytes Stimulated by Proinflammatory Mediators.

PubMed

Wang, Xiaoshuang; Yang, Liu; Yang, Li; Xing, Faping; Yang, Hua; Qin, Liyue; Lan, Yunyi; Wu, Hui; Zhang, Beibei; Shi, Hailian; Lu, Cheng; Huang, Fei; Wu, Xiaojun; Wang, Zhengtao

2017-12-01

Gypenoside IX (GP IX) is a pure compound isolated from Panax notoginseng. Gypenosides have been implicated to benefit the recovery of enormous neurological disorders. By suppressing the activation of astrocytes, gypenosides can improve the cognitive impairment. However, so far, little is known about whether GP IX could restrain the inflammatory responses in astrocytes or reactive astrogliosis. In present study, the anti-inflammatory effects of GP IX were investigated in reactive astrocytes induced by proinflammatory mediators both in vitro and in vivo. GP IX significantly reduced the production of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) at either protein or mRNA level in glial cell line C6 cells stimulated by lipopolysaccharide (LPS)/TNF-α combination. It also alleviated the astrogliosis and decreased the production of inflammatory mediators in brain cortex of LPS-treated mice. Further study disclosed that GP IX inhibited nuclear translocation of nuclear factor kappa B (NFκB) and reduced its transcriptional activity. Meanwhile, GP IX significantly attenuated the phosphorylation of NFκB, inhibitor of kappa B (IκB), Akt, and p38 mitogen-activated protein kinase (MAPK) under inflammatory conditions both in vitro and in vivo. These findings indicated that GP IX might suppress reactive astrogliosis by suppressing Akt/p38 MAPK/NFκB signaling pathways. And GP IX might be a promising drug candidate or prodrug for the therapy of neuroinflammatory disorders characterized with reactive astrogliosis.

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

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.

Ultrasound Tomography by Galerkin or Moment Methods,

DTIC Science & Technology

1983-05-05

in terms of i(x) . Let (31,32) gj~x) - J gji ~ix and G() W i(x) where i(x) is given by (24). Thus, by (25) the coefficients gji an Gqji are givenby...4 yK (mh,nh) y, (mh,nh) gji qji and i(mn)(X) Thus on factoring, we obtain f(S) (f - fu)). 2 (3) i i 4. i 0 ~ ko y,,Qxj)f 0 (,x,)g.. + A qjG bsil. 2

Influence of vector dose on factor IX-specific T and B cell responses in muscle-directed gene therapy.

PubMed

Herzog, Roland W; Fields, Paul A; Arruda, Valder R; Brubaker, Jeff O; Armstrong, Elina; McClintock, Darryl; Bellinger, Dwight A; Couto, Linda B; Nichols, Timothy C; High, Katherine A

2002-07-20

Intramuscular injection of an adeno-associated virus (AAV) vector has resulted in vector dose-dependent, stable expression of canine factor IX (cF.IX) in hemophilia B dogs with an F.IX missense mutation (Herzog et al., Nat. Med. 1999;5:56-63). The use of a species-specific transgene allowed us to study risks and characteristics of antibody formation against the therapeutic transgene product. We analyzed seven dogs that had been injected at a single time point at multiple intramuscular sites with varying vector doses (dose per kilogram, dose per animal, dose per site). Comparison of individual animals suggests an increased likelihood of inhibitory anti-cF.IX (inhibitor) development with increased vector doses, with dose per site showing the strongest correlation with the risk of inhibitor formation. In six of seven animals, such immune responses were either absent or transient, and therefore did not prevent sustained systemic expression of cF.IX. Transient inhibitory/neutralizing anti-cF.IX responses occurred at vector doses of 2 x 10(12)/site, whereas a 6-fold higher dose resulted in a longer lasting, higher titer inhibitor. Anti-cF.IX was efficiently blocked in an eighth animal that was injected with a high vector dose per site, but in addition received transient immune suppression. Inhibitor formation was characterized by synthesis of two IgG subclasses and in vitro proliferation of lymphocytes to cF.IX antigen, indicating a helper T cell-dependent mechanism. Anti-cF.IX formation is likely influenced by the extent of local antigen presentation and may be avoided by limited vector doses or by transient immune modulation.

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.

Inelastic X-ray scattering of RTAl3 (R = La, Ce, T = Cu, Au)

NASA Astrophysics Data System (ADS)

Tsutsui, Satoshi; Kaneko, Koji; Pospisil, Jiri; Haga, Yoshinori

2018-05-01

Inelastic X-ray scattering (IXS) experiments of RTAl3 (R = La Ce, T = Cu, Au) were carried out at 300 and 5.5 K. The spectra between LaCuAl3 and CeCuAl3 (LaAuAl3 and CeAuAl3) are nearly identical at both temperatures except for temperature factors such as temperature dependence of Bose factor in IXS spectra and effect on thermal expansion. This means that no evident temperature dependence of IXS spectra was observed in CeTAl3 (T = Cu, Au). Since the major contribution of scattering cross section in IXS measurements is Thomson scattering, the present results failed to confirm the presence of vibron in these compounds.

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.

Coronary artery bypass grafting in a patient with hemophilia B: continuous recombinant factor IX infusion as per the Japanese guidelines for replacement therapy.

PubMed

Suzuki, Tomoyuki; Kawamoto, Shunsuke; Kumagai, Kiichiro; Adachi, Osamu; Kanda, Keisuke; Ishikawa, Masaaki; Okitsu, Yoko; Harigae, Hideo; Kurosawa, Shin; Saiki, Yoshikatsu

2016-08-01

We herein report our experience of successfully managing the hemostatic system by controlling serum factor IX levels throughout the perioperative period in a patient with hemophilia B. Coronary artery bypass grafting with cardiopulmonary bypass was planned for a 52-year-old man with moderate severity of hemophilia B. During surgery, recombinant factor IX (rFIX; BeneFIX(®) Pfizer Japan inc., Tokyo, Japan) was administered by bolus infusion followed by continuous infusion as per the guidelines of the Japanese Society on Thrombosis and Hemostasis. The operative course was uneventful without any considerable bleeding or complications.

Factor IX gene haplotypes in Amerindians.

PubMed

Franco, R F; Araújo, A G; Zago, M A; Guerreiro, J F; Figueiredo, M S

1997-02-01

We have determined the haplotypes of the factor IX gene for 95 Indians from 5 Brazilian Amazon tribes: Wayampí, Wayana-Apalaí, Kayapó, Arára, and Yanomámi. Eight polymorphisms linked to the factor IX gene were investigated: MseI (at 5', nt -698), BamHI (at 5', nt -561), DdeI (intron 1), BamHI (intron 2), XmnI (intron 3), TaqI (intron 4), MspI (intron 4), and HhaI (at 3', approximately 8 kb). The results of the haplotype distribution and the allele frequencies for each of the factor IX gene polymorphisms in Amerindians were similar to the results reported for Asian populations but differed from results for other ethnic groups. Only five haplotypes were identified within the entire Amerindian study population, and the haplotype distribution was significantly different among the five tribes, with one (Arára) to four (Wayampí) haplotypes being found per tribe. These findings indicate a significant heterogeneity among the Indian tribes and contrast with the homogeneous distribution of the beta-globin gene cluster haplotypes but agree with our recent findings on the distribution of alpha-globin gene cluster haplotypes and the allele frequencies for six VNTRs in the same Amerindian tribes. Our data represent the first study of factor IX-associated polymorphisms in Amerindian populations and emphasizes the applicability of these genetic markers for population and human evolution studies.

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 Q analyzer, a new cap-piercing fully automated coagulometer with clotting, chromogenic, and immunoturbidometric capability.

PubMed

Kitchen, Steve; Woolley, Anita

2013-01-01

The Q analyzer is a recently launched fully automated photo-optical analyzer equipped with primary tube cap-piercing and capable of clotting, chromogenic, and immunoturbidometric tests. The purpose of the present study was to evaluate the performance characteristics of the Q analyzer with reagents from the instrument manufacturer. We assessed precision and throughput when performing coagulation screening tests, prothrombin time (PT)/international normalized ratio (INR), activated partial thromboplastin time (APTT), and fibrinogen assay by Clauss assay. We compared results with established reagent instrument combinations in widespread use. Precision of PT/INR and APTT was acceptable as indicated by total precision of around 3%. The time to first result was 3  min for an INR and 5  min for PT/APTT. The system produced 115 completed samples per hour when processing only INRs and 60 samples (120 results) per hour for PT/APTT combined. The sensitivity of the DG-APTT Synth/Q method to mild deficiency of factor VIII (FVIII), IX, and XI was excellent (as indicated by APTTs being prolonged above the upper limit of the reference range). The Q analyzer was associated with high precision, acceptable throughput, and good reliability. When used in combination with DG-PT reagent and manufacturer's instrument-specific international sensitivity index, the INRs obtained were accurate. The Q analyzer with DG-APTT Synth reagent demonstrated good sensitivity to isolated mild deficiency of FVIII, IX, and XI and had the advantage of relative insensitivity to mild FXII deficiency. Taken together, our data indicate that the Q hemostasis analyzer was suitable for routine use in combination with the reagents evaluated.

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

Emerging drugs for hemophilia B.

PubMed

Mannucci, Pier Mannuccio; Franchini, Massimo

2014-09-01

Hemophilia B is a rare congenital bleeding disorder characterized by a deficiency of coagulation factor IX (FIX). Hemophilia B patients experience mild-to-severe bleeding complications according to the degree of FIX defect. Prophylaxis, with regular infusion of FIX concentrates, is nowadays, the mainstay of hemophilia care. However, because the relatively short half-life of such products necessitates frequent infusions and thus makes patients' adherence difficult, a number of strategies have been implemented to improve the pharmacokinetics of FIX clotting factors. This review summarizes the main results of Phase I/II and III studies on new FIX molecules engineered to have a longer half-life. Several technologies are being applied to extend FIX half-life, including Fc fusion, recombinant (r) albumin fusion and the addition of PEG polymers. By prolonging the FIX half-life up to 5 times, long-acting FIX products are expected to substantially improve the management of hemophilia B patients, allowing less frequent infusions and improving patients' adherence to prophylactic regimens and individualized treatments. Some of them are at an advanced stage of development, such as the rFIX-Fc which has been launched in March 2014. Along with the ongoing Phase III trials, long-term post-marketing surveillance studies are needed to assess their safety and effectiveness and their impact on patients' quality of life.

Qualification of a select one-stage activated partial thromboplastin time-based clotting assay and two chromogenic assays for the post-administration monitoring of nonacog beta pegol.

PubMed

Tiefenbacher, S; Bohra, R; Amiral, J; Bowyer, A; Kitchen, S; Lochu, A; Rosén, S; Ezban, M

2017-10-01

Essentials Nonacog beta pegol (N9-GP) is an extended half-life, recombinant human factor IX (FIX). One-stage clotting (OSC) and chromogenic FIX activity assays were assessed for N9-GP recovery. OSC STA ® -Cephascreen ® , ROX FIX and BIOPHEN FIX chromogenic assays were qualified for N9-GP. Other extended half-life factor products should be assessed in a similar way prior to approval. Background Nonacog beta pegol (N9-GP) is an extended half-life, glycoPEGylated recombinant human factor IX that is under development for the prophylaxis and treatment of bleeding episodes in hemophilia B patients. Considerable reagent-dependent variability has been observed when one-stage clotting assays are used to measure the recovery of recombinant FIX products, including N9-GP. Objective To qualify select one-stage clotting and chromogenic FIX activity assays for measuring N9-GP recovery. Methods The accuracy and precision of the one-stage clotting assay (with the STA-Cephascreen activated partial thromboplastin [APTT] reagent) and the ROX Factor IX and BIOPHEN Factor IX chromogenic assays for measuring N9-GP recovery were assessed in N9-GP-spiked hemophilia B plasma samples in a systematic manner at three independent sites, with manufacturer-recommended protocols and/or site-specific assay setups, including different instruments. Results For each of the three FIX activity assays qualified on five different reagent-instrument systems, acceptable intra-assay and interassay accuracy and precision, dilution integrity, reagent robustness and freeze-thaw and short-term sample stabilities were demonstrated. The STA-Cephascreen assay showed a limited reportable range at one of the three qualification sites, and the BIOPHEN Factor IX assay showed suspect low-end sensitivity at one of the three qualification sites. An individual laboratory would account for these limitations by adjusting the assay's reportable range; thus, these findings are not considered to impact the respective assay qualifications. Conclusion The one-stage clotting assay with the STA-Cephascreen APTT reagent, the ROX Factor IX chromogenic assay and the BIOPHEN Factor IX chromogenic assay are considered to be qualified for the measurement of N9-GP in 3.2% (0.109 m) citrated human plasma. © 2017 International Society on Thrombosis and Haemostasis.

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.

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.

δ-aminolevulinic acid–induced protoporphyrin IX concentration correlates with histopathologic markers of malignancy in human gliomas: the need for quantitative fluorescence-guided resection to identify regions of increasing malignancy

PubMed Central

Valdés, Pablo A.; Kim, Anthony; Brantsch, Marco; Niu, Carolyn; Moses, Ziev B.; Tosteson, Tor D.; Wilson, Brian C.; Paulsen, Keith D.; Roberts, David W.; Harris, Brent T.

2011-01-01

Extent of resection is a major goal and prognostic factor in the treatment of gliomas. In this study we evaluate whether quantitative ex vivo tissue measurements of δ-aminolevulinic acid–induced protoporphyrin IX (PpIX) identify regions of increasing malignancy in low- and high-grade gliomas beyond the capabilities of current fluorescence imaging in patients undergoing fluorescence-guided resection (FGR). Surgical specimens were collected from 133 biopsies in 23 patients and processed for ex vivo neuropathological analysis: PpIX fluorimetry to measure PpIX concentrations (CPpIX) and Ki-67 immunohistochemistry to assess tissue proliferation. Samples displaying visible levels of fluorescence showed significantly higher levels of CPpIX and tissue proliferation. CPpIX was strongly correlated with histopathological score (nonparametric) and tissue proliferation (parametric), such that increasing levels of CPpIX were identified with regions of increasing malignancy. Furthermore, a large percentage of tumor-positive biopsy sites (∼40%) that were not visibly fluorescent under the operating microscope had levels of CPpIX greater than 0.1 µg/mL, which indicates that significant PpIX accumulation exists below the detection threshold of current fluorescence imaging. Although PpIX fluorescence is recognized as a visual biomarker for neurosurgical resection guidance, these data show that it is quantitatively related at the microscopic level to increasing malignancy in both low- and high-grade gliomas. This work suggests a need for improved PpIX fluorescence detection technologies to achieve better sensitivity and quantification of PpIX in tissue during surgery. PMID:21798847

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.

Carbonic Anhydrase IX Interacts with Bicarbonate Transporters in Lamellipodia and Increases Cell Migration via Its Catalytic Domain*

PubMed Central

Svastova, Eliska; Witarski, Wojciech; Csaderova, Lucia; Kosik, Ivan; Skvarkova, Lucia; Hulikova, Alzbeta; Zatovicova, Miriam; Barathova, Monika; Kopacek, Juraj; Pastorek, Jaromir; Pastorekova, Silvia

2012-01-01

Carbonic anhydrase IX (CA IX) is a hypoxia-induced cell surface enzyme expressed in solid tumors, and functionally involved in acidification of extracellular pH and destabilization of intercellular contacts. Since both extracellular acidosis and reduced cell adhesion facilitate invasion and metastasis, we investigated the role of CA IX in cell migration, which promotes the metastatic cascade. As demonstrated here, ectopically expressed CA IX increases scattering, wound healing and transwell migration of MDCK cells, while an inactive CA IX variant lacking the catalytic domain (ΔCA) fails to do so. Correspondingly, hypoxic HeLa cells exhibit diminished migration upon inactivation of the endogenous CA IX either by forced expression of the dominant-negative ΔCA variant or by treatment with CA inhibitor, implying that the catalytic activity is indispensable for the CA IX function. Interestingly, CA IX improves cell migration both in the absence and presence of hepatocyte growth factor (HGF), an established inducer of epithelial-mesenchymal transition. On the other hand, HGF up-regulates CA IX transcription and triggers CA IX protein accumulation at the leading edge of lamellipodia. In these membrane regions CA IX co-localizes with sodium bicarbonate co-transporter (NBCe1) and anion exchanger 2 (AE2) that are both components of the migration apparatus and form bicarbonate transport metabolon with CA IX. Moreover, CA IX physically interacts with AE2 and NBCe1 in situ, as shown here for the first time. Thus, our findings suggest that CA IX actively contributes to cell migration via its ability to facilitate ion transport and pH control at protruding fronts of moving cells. PMID:22170054

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.

[Transcription factors NF-kB, HIF-1, HIF-2, growth factor VEGF, VEGFR2 and carboanhydrase IX mRNA and protein level in the development of kidney cancer metastasis].

PubMed

Spirina, L V; Usynin, Y A; Yurmazov, Z A; Slonimskaya, E M; Kolegova, E S; Kondakova, I V

2017-01-01

Here, we have investigated the participation of nuclear factors NF-kB, HIF-1 and HIF-2, VEGF, VEGFR2, and carboanhydrase IX in clear-cell renal cancer. We have determined the expression and protein level of transcription factors, VEGF, VEGFR2, and carboanhydrase IX in tumor and normal tissues of 30 patients with kidney cancer. The Real-Time PCR and ELISA were used in the study. The low levels of HIF-1 mRNA expression associated with high levels of HIF-1 protein were also associated with metastasis. The expression levels of VEGF, VEGFR2, and their protein levels are increased in primary tumors of patients with disseminated kidney cancer compared to nonmetastatic cancer. No correlation was revealed between the content of mRNA and encoded proteins in the kidney cancer tissues. The changes in the ratios of mRNA levels and the respective proteins (HIF-1α, HIF-2, NF-kB, VEGF, VEGFR2, and carboanhydrase IX) may contribute to kidney-cancer metastasis.

Diagnosing human blood clotting deficiency.

PubMed

Ong, Chong Cheen; Gopinath, Subash C B; Rebecca, Leong Wei Xian; Perumal, Veeradasan; Lakshmipriya, Thangavel; Saheed, Mohamed Shuaib Mohamed

2018-05-15

There are different clotting factors present in blood, carries the clotting cascade and excessive bleeding may cause a deficiency in the clotting Diagnosis of this deficiency in clotting drastically reduces the potential fatality. For enabling a sensor to detect the clotting factors, suitable probes such as antibody and aptamer have been used to capture these targets on the sensing surface. Two major clotting factors were widely studied for the diagnosis of clotting deficiency, which includes factor IX and thrombin. In addition, factor IX is considered as the substitute for heparin and the prothrombotic associated with the increased thrombin generation are taking into account their prevalence. The biosensors, surface plasmon resonance, evanescent-field-coupled waveguide-mode sensor, metal-enhanced PicoGreen fluorescence and electrochemical aptasensor were well-documented and improvements have been made for high-performance sensing. We overviewed detecting factor IX and thrombin using these biosensors, for the potential application in medical diagnosis. Copyright © 2018 Elsevier B.V. All rights reserved.

Factor IX expression in skeletal muscle of a severe hemophilia B patient 10 years after AAV-mediated gene transfer

PubMed Central

Buchlis, George; Podsakoff, Gregory M.; Radu, Antonetta; Hawk, Sarah M.; Flake, Alan W.; Mingozzi, Federico

2012-01-01

In previous work we transferred a human factor IX–encoding adeno-associated viral vector (AAV) into skeletal muscle of men with severe hemophilia B. Biopsy of injected muscle up to 1 year after vector injection showed evidence of gene transfer by Southern blot and of protein expression by IHC and immunofluorescent staining. Although the procedure appeared safe, circulating F.IX levels remained subtherapeutic (< 1%). Recently, we obtained muscle tissue from a subject injected 10 years earlier who died of causes unrelated to gene transfer. Using Western blot, IHC, and immunofluorescent staining, we show persistent factor IX expression in injected muscle tissue. F.IX transcripts were detected in injected skeletal muscle using RT-PCR, and isolated whole genomic DNA tested positive for the presence of the transferred AAV vector sequence. This is the longest reported transgene expression to date from a parenterally administered AAV vector, with broad implications for the future of muscle-directed gene transfer. PMID:22271447

ABCG2 transporter inhibitor restores the sensitivity of triple negative breast cancer cells to aminolevulinic acid-mediated photodynamic therapy.

PubMed

Palasuberniam, Pratheeba; Yang, Xue; Kraus, Daniel; Jones, Patrick; Myers, Kenneth A; Chen, Bin

2015-08-18

Photosensitizer protoporphyrin IX (PpIX) fluorescence, intracellular localization and cell response to photodynamic therapy (PDT) were analyzed in MCF10A normal breast epithelial cells and a panel of human breast cancer cells including estrogen receptor (ER) positive, human epidermal growth factor receptor 2 (HER2) positive and triple negative breast cancer (TNBC) cells after treatment with PpIX precursor aminolevulinic acid (ALA). Although PpIX fluorescence was heterogeneous in different cells, TNBC cells showed significantly lower PpIX level than MCF10A and ER- or HER2-positive cells. PpIX fluorescence in TNBC cells also had much less mitochondrial localization than other cells. There was an inverse correlation between PpIX fluorescence and cell viability after PDT. Breast cancer cells with the highest PpIX fluorescence were the most sensitive to ALA-PDT and TNBC cells with the lowest PpIX level were resistant to PDT. Treatment of TNBC cells with ABCG2 transporter inhibitor Ko143 significantly increased ALA-PpIX fluorescence, enhanced PpIX mitochondrial accumulation and sensitized cancer cells to ALA-PDT. Ko143 treatment had little effect on PpIX production and ALA-PDT in normal and ER- or HER2-positive cells. These results demonstrate that enhanced ABCG2 activity renders TNBC cell resistance to ALA-PDT and inhibiting ABCG2 transporter is a promising approach for targeting TNBC with ALA-based modality.

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.

Clinical utility and patient perspectives on the use of extended half-life rFIXFc in the management of hemophilia B

PubMed Central

Miguelino, Maricel G; Powell, Jerry S

2014-01-01

Hemophilia B is an X-linked genetic disease caused by mutation of the gene for coagulation protein factor IX (FIX), with an incidence of approximately once every 30,000 male births in all populations and ethnic groups. When severe, the disease leads to spontaneous life threatening bleeding episodes. When untreated, most patients die from bleeding complications before 25 years of age. Current therapy requires frequent intravenous infusions of therapeutic recombinant or plasma-derived protein concentrates containing FIX. Most patients administer the infusions at home every few days, and must limit their physical activities to avoid abnormal bleeding when the FIX activity levels are below normal. After completing the pivotal Phase III clinical trial, a new therapeutic FIX preparation that has been engineered for an extended half-life in circulation, received regulatory approval in March 2014 in Canada and the US. This new FIX represents a major therapeutic advance for patients with hemophilia B. The half-life is prolonged due to fusion of the native FIX molecule with the normal constant region of immunoglobulin G. This fusion molecule then follows the normal immunoglobulin recirculation pathways through endothelial cells, resulting in prolonged times in circulation. In the clinical trials, over 150 patients successfully used eftrenonacog alfa regularly for more than 1 year to prevent spontaneous bleeding, to successfully treat any bleeding episodes, and to provide effective coagulation for major surgery. All infusions were well tolerated and effective, with no inhibitors detected and no safety concerns. This promising therapy should allow patients to use fewer infusions to maintain appropriate FIX activity levels in all clinical settings. PMID:25143713

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

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...

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.

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.

Translational Data from Adeno-Associated Virus-Mediated Gene Therapy of Hemophilia B in Dogs

PubMed Central

Whitford, Margaret H.; Arruda, Valder R.; Stedman, Hansell H.; Kay, Mark A.; High, Katherine A.

2015-01-01

Abstract Preclinical testing of new therapeutic strategies in relevant animal models is an essential part of drug development. The choice of animal models of disease that are used in these studies is driven by the strength of the translational data for informing about safety, efficacy, and success or failure of human clinical trials. Hemophilia B is a monogenic, X-linked, inherited bleeding disorder that results from absent or dysfunctional coagulation factor IX (FIX). Regarding preclinical studies of adeno-associated virus (AAV)-mediated gene therapy for hemophilia B, dogs with severe hemophilia B (<1% FIX) provide well-characterized phenotypes and genotypes in which a species-specific transgene can be expressed in a mixed genetic background. Correction of the hemophilic coagulopathy by sustained expression of FIX, reduction of bleeding events, and a comprehensive assessment of the humoral and cell-mediated immune responses to the expressed transgene and recombinant AAV vector are all feasible end points in these dogs. This review compares the preclinical studies of AAV vectors used to treat dogs with hemophilia B with the results obtained in subsequent human clinical trials using muscle- and liver-based approaches. PMID:25675273

Vector modifications to eliminate transposase expression following piggyBac-mediated transgenesis

PubMed Central

Chakraborty, Syandan; Ji, HaYeun; Chen, Jack; Gersbach, Charles A.; Leong, Kam W.

2014-01-01

Transgene insertion plays an important role in gene therapy and in biological studies. Transposon-based systems that integrate transgenes by transposase-catalyzed “cut-and-paste” mechanism have emerged as an attractive system for transgenesis. Hyperactive piggyBac transposon is particularly promising due to its ability to integrate large transgenes with high efficiency. However, prolonged expression of transposase can become a potential source of genotoxic effects due to uncontrolled transposition of the integrated transgene from one chromosomal locus to another. In this study we propose a vector design to decrease post-transposition expression of transposase and to eliminate the cells that have residual transposase expression. We design a single plasmid construct that combines the transposase and the transpositioning transgene element to share a single polyA sequence for termination. Consequently, the separation of the transposase element from the polyA sequence after transposition leads to its deactivation. We also co-express Herpes Simplex Virus thymidine kinase (HSV-tk) with the transposase. Therefore, cells having residual transposase expression can be eliminated by the administration of ganciclovir. We demonstrate the utility of this combination transposon system by integrating and expressing a model therapeutic gene, human coagulation Factor IX, in HEK293T cells. PMID:25492703

Translational data from adeno-associated virus-mediated gene therapy of hemophilia B in dogs.

PubMed

Nichols, Timothy C; Whitford, Margaret H; Arruda, Valder R; Stedman, Hansell H; Kay, Mark A; High, Katherine A

2015-03-01

Preclinical testing of new therapeutic strategies in relevant animal models is an essential part of drug development. The choice of animal models of disease that are used in these studies is driven by the strength of the translational data for informing about safety, efficacy, and success or failure of human clinical trials. Hemophilia B is a monogenic, X-linked, inherited bleeding disorder that results from absent or dysfunctional coagulation factor IX (FIX). Regarding preclinical studies of adeno-associated virus (AAV)-mediated gene therapy for hemophilia B, dogs with severe hemophilia B (<1% FIX) provide well-characterized phenotypes and genotypes in which a species-specific transgene can be expressed in a mixed genetic background. Correction of the hemophilic coagulopathy by sustained expression of FIX, reduction of bleeding events, and a comprehensive assessment of the humoral and cell-mediated immune responses to the expressed transgene and recombinant AAV vector are all feasible end points in these dogs. This review compares the preclinical studies of AAV vectors used to treat dogs with hemophilia B with the results obtained in subsequent human clinical trials using muscle- and liver-based approaches.

In Vivo Gene Therapy of Hemophilia B: Sustained Partial Correction in Factor IX-Deficient Dogs

NASA Astrophysics Data System (ADS)

Kay, Mark A.; Rothenberg, Steven; Landen, Charles N.; Bellinger, Dwight A.; Leland, Frances; Toman, Carol; Finegold, Milton; Thompson, Arthur R.; Read, M. S.; Brinkhous, Kenneth M.; Woo, Savio L. C.

1993-10-01

The liver represents a model organ for gene therapy. A method has been developed for hepatic gene transfer in vivo by the direct infusion of recombinant retroviral vectors into the portal vasculature, which results in the persistent expression of exogenous genes. To determine if these technologies are applicable for the treatment of hemophilia B patients, preclinical efficacy studies were done in a hemophilia B dog model. When the canine factor IX complementary DNA was transduced directly into the hepatocytes of affected dogs in vivo, the animals constitutively expressed low levels of canine factor IX for more than 5 months. Persistent expression of the clotting. factor resulted in reductions of whole blood clotting and partial thromboplastin times of the treated animals. Thus, long-term treatment of hemophilia B patients may be feasible by direct hepatic gene therapy in vivo.

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.

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.

Long-Term Safety and Efficacy of Factor IX Gene Therapy in Hemophilia B

PubMed Central

Nathwani, A.C.; Reiss, U.M.; Tuddenham, E.G.D.; Rosales, C.; Chowdary, P.; McIntosh, J.; Della Peruta, M.; Lheriteau, E.; Patel, N.; Raj, D.; Riddell, A.; Pie, J.; Rangarajan, S.; Bevan, D.; Recht, M.; Shen, Y.-M.; Halka, K.G.; Basner-Tschakarjan, E.; Mingozzi, F.; High, K.A.; Allay, J.; Kay, M.A.; Ng, C.Y.C.; Zhou, J.; Cancio, M.; Morton, C.L.; Gray, J.T.; Srivastava, D.; Nienhuis, A.W.; Davidoff, A.M.

2014-01-01

BACKGROUND In patients with severe hemophilia B, gene therapy that is mediated by a novel self-complementary adeno-associated virus serotype 8 (AAV8) vector has been shown to raise factor IX levels for periods of up to 16 months. We wanted to determine the durability of transgene expression, the vector dose–response relationship, and the level of persistent or late toxicity. METHODS We evaluated the stability of transgene expression and long-term safety in 10 patients with severe hemophilia B: 6 patients who had been enrolled in an initial phase 1 dose-escalation trial, with 2 patients each receiving a low, intermediate, or high dose, and 4 additional patients who received the high dose (2×1012 vector genomes per kilogram of body weight). The patients subsequently underwent extensive clinical and laboratory monitoring. RESULTS A single intravenous infusion of vector in all 10 patients with severe hemophilia B resulted in a dose-dependent increase in circulating factor IX to a level that was 1 to 6% of the normal value over a median period of 3.2 years, with observation ongoing. In the high-dose group, a consistent increase in the factor IX level to a mean (±SD) of 5.1±1.7% was observed in all 6 patients, which resulted in a reduction of more than 90% in both bleeding episodes and the use of prophylactic factor IX concentrate. A transient increase in the mean alanine aminotransferase level to 86 IU per liter (range, 36 to 202) occurred between week 7 and week 10 in 4 of the 6 patients in the high-dose group but resolved over a median of 5 days (range, 2 to 35) after prednisolone treatment. CONCLUSIONS In 10 patients with severe hemophilia B, the infusion of a single dose of AAV8 vector resulted in long-term therapeutic factor IX expression associated with clinical improvement. With a follow-up period of up to 3 years, no late toxic effects from the therapy were reported. (Funded by the National Heart, Lung, and Blood Institute and others; ClinicalTrials.gov number, NCT00979238.) PMID:25409372

Impact of the underlying mutation and the route of vector administration on immune responses to factor IX in gene therapy for hemophilia B.

PubMed

Cao, Ou; Hoffman, Brad E; Moghimi, Babak; Nayak, Sushrusha; Cooper, Mario; Zhou, Shangzhen; Ertl, Hildegund C J; High, Katherine A; Herzog, Roland W

2009-10-01

Immune responses to factor IX (F.IX), a major concern in gene therapy for hemophilia, were analyzed for adeno-associated viral (AAV-2) gene transfer to skeletal muscle and liver as a function of the F9 underlying mutation. Vectors identical to those recently used in clinical trials were administered to four lines of hemophilia B mice on a defined genetic background [C3H/HeJ with deletion of endogenous F9 and transgenic for a range of nonfunctional human F.IX (hF.IX) variants]. The strength of the immune response to AAV-encoded F.IX inversely correlated with the degree of conservation of endogenous coding information and levels of endogenous antigen. Null mutation animals developed T- and B-cell responses in both protocols. However, inhibitor titers were considerably higher upon muscle gene transfer (or protein therapy). Transduced muscles of Null mice had strong infiltrates with CD8+ cells, which were much more limited in the liver and not seen for the other mutations. Sustained expression was achieved with liver transduction in mice with crm(-) nonsense and missense mutations, although they still formed antibodies upon muscle gene transfer. Therefore, endogenous expression prevented T-cell responses more effectively than antibody formation, and immune responses varied substantially depending on the protocol and the underlying mutation.

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

Simultaneous generation of aptamers to multiple gamma-carboxyglutamic acid proteins from a focused aptamer library using DeSELEX and convergent selection.

PubMed

Layzer, Juliana M; Sullenger, Bruce A

2007-01-01

By using the in vitro selection method SELEX against the complex mixture of GLA proteins and utilizing methods to deconvolute the resulting ligands, we were able to successfully generate 2'-ribo purine, 2'-fluoro pyrimidine aptamers to various individual targets in the GLA protein proteome that ranged in concentration from 10 nM to 1.4 microM in plasma. Perhaps not unexpectedly, the majority of the aptamers isolated following SELEX bind the most abundant protein in the mixture, prothrombin (FII), with high affinity. We show that by deselecting the dominant prothrombin aptamer the selection can be redirected. By using this DeSELEX approach, we were able to shift the selection toward other sequences and to less abundant protein targets and obtained an aptamer to Factor IX (FIX). We also demonstrate that by using an RNA library that is focused around a proteome, purified protein targets can then be used to rapidly generate aptamers to the protein targets that are rare in the initial mixture such as Factor VII (FVII) and Factor X (FX). Moreover, for all four proteins targeted (FII, FVII, FIX, and FX), aptamers were identified that could inhibit the individual protein's activitity in coagulation assays. Thus, by applying the concepts of DeSELEX and focused library selection, aptamers specific for any protein in a particular proteome can theoretically be generated, even when the proteins in the mixture are present at very different concentrations.

Ongoing advances in quantitative PpIX fluorescence guided intracranial tumor resection (Conference Presentation)

NASA Astrophysics Data System (ADS)

Olson, Jonathan D.; Kanick, Stephen C.; Bravo, Jaime J.; Roberts, David W.; Paulsen, Keith D.

2016-03-01

Aminolevulinc-acid induced protoporphyrin IX (ALA-PpIX) is being investigated as a biomarker to guide neurosurgical resection of brain tumors. ALA-PpIX fluorescence can be observed visually in the surgical field; however, raw fluorescence emissions can be distorted by factors other than the fluorophore concentration. Specifically, fluorescence emissions are mixed with autofluorescence and attenuated by background absorption and scattering properties of the tissue. Recent work at Dartmouth has developed advanced fluorescence detection approaches that return quantitative assessments of PpIX concentration, which are independent of background optical properties. The quantitative fluorescence imaging (qFI) approach has increased sensitivity to residual disease within the resection cavity at the end of surgery that was not visible to the naked eye through the operating microscope. This presentation outlines clinical observations made during an ongoing investigation of ALA-PpIX based guidance of tumor resection. PpIX fluorescence measurements made in a wide-field hyperspectral imaging approach are co-registered with point-assessment using a fiber optic probe. Data show variations in the measured PpIX accumulation among different clinical tumor grades (i.e. high grade glioma, low grade glioma), types (i.e. primary tumors. metastases) and normal structures of interest (e.g. normal cortex, hippocampus). These results highlight the contrast enhancement and underscore the potential clinical benefit offered from quantitative measurements of PpIX concentration during resection of intracranial tumors.

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.

[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.

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.

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.

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

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

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).

Real-World Analysis of Dispensed IUs of Coagulation Factor IX and Resultant Expenditures in Hemophilia B Patients Receiving Standard Half-life Versus Extended Half-life Products and Those Switching from Standard Half-life to Extended Half-life Products.

PubMed

Tortella, Bartholomew J; Alvir, José; McDonald, Margaret; Spurden, Dean; Fogarty, Patrick F; Chhabra, Amit; Pleil, Andreas M

2018-01-24

Hemophilia B requires replacement therapy with factor IX (FIX) coagulation products to treat and prevent bleeding episodes. A recently introduced extended half-life (EHL) recombinant FIX replacement product provided the opportunity to compare the amount of dispensed factor and expenditures for EHL treatment compared with a standard half-life (SHL) product. To determine factor international units (IUs) dispensed and expenditures associated with switching from nonacog alfa, the most commonly used SHL replacement product, to eftrenonacog alfa, an EHL FIX replacement product. Two U.S. claims databases were analyzed. A large national specialty pharmacy dispensation claims database was used to identify the number of IUs dispensed and monthly charges for all patients with hemophilia B from April 2015 to June 2016. Truven Health MarketScan Research Databases (January 2010-July 2016) were used to identify IUs and expenditures for patients with claims data for at least 3 months before and after switching from the SHL to the EHL product. Medians for IUs and expenditures are presented to accommodate for skewness of data distribution. The national specialty pharmacy database analysis included 296 patients with moderate or severe hemophilia B (233 on SHL; 94 on EHL). Median monthly factor dispensed was 11% lower (2,142 IU) in the EHL versus SHL cohort over the study period, while individual monthly reductions ranged from 32% to 47% (9,838 IU to 16,514 IU). Using the wholesale acquisition cost, the median per-patient monthly factor expenditures over the 15-month study period were 94% higher ($23,005) for the EHL than for the SHL product. Individual median monthly expenditure differences ranged from 15% ($6,562) to 49% ($19,624). In the Truven database, 14 patients switched from the SHL to the EHL product. The amount of factor dispensed was variable; in the 1-year period before and after the switch from the SHL to the EHL product, mean IUs dispensed decreased by 3,005 IU, while median IUs dispensed increased by 4,775 IU. Factor replacement expenditures were higher after switching from the SHL to the EHL product in each of the 3-month periods examined before versus after the switch. This analysis of real-world data showed that switching from the SHL to the EHL product was associated with higher expenditures. Increased expenditures noted in the first 3 months after switching may be related to initial stocking up of the EHL product, but expenditures were sustained throughout the 1-year period of data analysis. Further analysis of these findings with larger numbers of patients should be explored. This study was sponsored by Pfizer. Pfizer employees were involved in the study design; the collection, analysis, and interpretation of data; the review of the manuscript; and the decision to submit for publication. All authors are employees of Pfizer. No author received an honorarium or other form of payment related to the development of this manuscript. All authors participated in the study design, data interpretation, and manuscript review and revisions and granted approval for the submission of the manuscript. Alvir, McDonald, and Tortella also participated in data analysis. Data from this paper were presented in part at the European Association for Haemophilia and Allied Disorders Annual Meeting, February 1-3, 2017, Paris, France; at the International Society for Pharmacoeconomics and Outcomes Research Annual Meeting, May 20-24, 2017, Boston, Massachusetts; and at the International Society on Thrombosis and Haemostasis Congress, July 8-13, 2017, Berlin, Germany.

Use of proteomics for validation of the isolation process of clotting factor IX from human plasma.

PubMed

Clifton, James; Huang, Feilei; Gaso-Sokac, Dajana; Brilliant, Kate; Hixson, Douglas; Josic, Djuro

2010-01-03

The use of proteomic techniques in the monitoring of different production steps of plasma-derived clotting factor IX (pd F IX) was demonstrated. The first step, solid-phase extraction with a weak anion-exchange resin, fractionates the bulk of human serum albumin (HSA), immunoglobulin G, and other non-binding proteins from F IX. The proteins that strongly bind to the anion-exchange resin are eluted by higher salt concentrations. In the second step, anion-exchange chromatography, residual HSA, some proteases and other contaminating proteins are separated. In the last chromatographic step, affinity chromatography with immobilized heparin, the majority of the residual impurities are removed. However, some contaminating proteins still remain in the eluate from the affinity column. The next step in the production process, virus filtration, is also an efficient step for the removal of residual impurities, mainly high molecular weight proteins, such as vitronectin and inter-alpha inhibitor proteins. In each production step, the active component, pd F IX and contaminating proteins are monitored by biochemical and immunochemical methods and by LC-MS/MS and their removal documented. Our methodology is very helpful for further process optimization, rapid identification of target proteins with relatively low abundance, and for the design of subsequent steps for their removal or purification.

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.

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

Expression of hypoxia-inducible carbonic anhydrases in brain tumors

PubMed Central

Proescholdt, Martin A.; Mayer, Christina; Kubitza, Marion; Schubert, Thomas; Liao, Shu-Yuan; Stanbridge, Eric J.; Ivanov, Sergey; Oldfield, Edward H.; Brawanski, Alexander; Merrill, Marsha J.

2005-01-01

Malignant brain tumors exhibit distinct metabolic characteristics. Despite high levels of lactate, the intracellular pH of brain tumors is more alkaline than normal brain. Additionally, with increasing malignancy, brain tumors display intratumoral hypoxia. Carbonic anhydrase (CA) IX and XII are transmembrane isoenzymes that are induced by tissue hypoxia. They participate in regulation of pH homeostasis by catalyzing the reversible hydration of carbon dioxide. The aim of our study was to investigate whether brain tumors of different histology and grade of malignancy express elevated levels of CA IX and XII as compared to normal brain. We analyzed 120 tissue specimens from brain tumors (primary and metastatic) and normal brain for CA IX and XII expression by immunohistochemistry, Western blot, and in situ hybridization. Whereas normal brain tissue showed minimal levels of CA IX and XII expression, expression in tumors was found to be upregulated with increased level of malignancy. Hemangioblastomas, from patients with von Hippel–Lindau disease, also displayed high levels of CA IX and XII expression. Comparison of CA IX and XII staining with HIF-1α staining revealed a similar microanatomical distribution, indicating hypoxia as a major, but not the only, induction factor. The extent of CA IX and XII staining correlated with cell proliferation, as indicated by Ki67 labeling. The results demonstrate that CA IX and XII are upregulated in intrinsic and metastatic brain tumors as compared to normal brain tissue. This may contribute to the management of tumor-specific acid load and provide a therapeutic target. PMID:16212811

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

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

Establishment of the 2nd Korean national biological reference standard for blood coagulation factor VIII:C concentrate.

PubMed

Lee, Naery; Seo, Ji Suk; Kim, Jae Ok; Ban, Sang Ja

2017-05-01

Since the 1st Korean national biological reference standard for factor (F)VIII concentrate, established in 2001, has shown declining potency, we conducted this study to replace this standard with a 2nd Korean national biological reference standard for blood coagulation FVIII concentrate. The candidate materials for the 2nd standard were prepared in 8000 vials with 10 IU/ml of target potency, according to the approved manufacturing process of blood coagulation Factor VIII:C Monoclonal Antibody-purified, Freeze-dried Human Blood Coagulation Factor VIII:C. Potency was evaluated by one-stage clotting and chromogenic methods and the stability was confirmed to meet the specifications during a period of 73 months. Since the potencies obtained by the two methods differed significantly (P < 0.015), the values were determined separately according to the geometric means (8.9 and 7.4 IU/vial, respectively). The geometric coefficients of interlaboratory variability were 3.4% and 7.6% by the one-stage clotting and chromogenic assays, respectively. Copyright © 2017 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

[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.

Expression of ferrochelatase has a strong correlation in protoporphyrin IX accumulation with photodynamic detection of bladder cancer.

PubMed

Nakai, Yasushi; Tatsumi, Yoshihiro; Miyake, Makito; Anai, Satoshi; Kuwada, Masaomi; Onishi, Sayuri; Chihara, Yoshitomo; Tanaka, Nobumichi; Hirao, Yoshihiko; Fujimoto, Kiyohide

2016-03-01

The mechanism underlying the increased levels of protoporphyrin IX in bladder cancer remains unclear. Here, we focus on proteins associated with protoporphyrin IX accumulation in bladder cancer cells and investigate the protein that plays a key role in increased protoporphyrin IX accumulation in bladder cancer cells. Western blotting was used to determine the expression of peptide transporter 1, hydroxymethylbilane synthase, ferrochelatase, ATP-binding cassette 2, and heme oxygenase-1 in bladder cancer cell line cells. We evaluated the correlation between the expression of each protein and accumulated protoporphyrin IX in these cells using Pearson's correlation analysis. Immunohistochemistry was used to estimate the expression of the same five proteins in samples from 75 patients who underwent transurethral resection of bladder tumors. The correlation between the expression of each protein in cells from resected bladder specimens and accumulated protoporphyrin IX in bladder cancer cells in voided urine was evaluated using Pearson's correlation analysis. The expression of ferrochelatase showed a significant negative correlation with protoporphyrin IX accumulation in vitro (p=0.04). The expression of peptide transporter 1 (p<0.01, R=0.39), heme oxygenase-1 (p<0.01, R=0.33), and ferrochelatase (p<0.01, R=0.75) in resected bladder specimens by immunohistochemistry was correlated with protoporphyrin IX accumulation in bladder cancer cells in voided urine. On multivariate analysis, the expression of ferrochelatase (p=0.03) was significant factors to predict positive 5-aminolevulinic acid-induced fluorescent cytology. The expression of ferrochelatase has a strong correlation in protoporphyrin IX accumulation with photodynamic detection of bladder cancer. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

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.

Continuous prophylaxis with recombinant factor IX Fc fusion protein and conventional recombinant factor IX products: comparisons of efficacy and weekly factor consumption.

PubMed

Iorio, Alfonso; Krishnan, Sangeeta; Myrén, Karl-Johan; Lethagen, Stefan; McCormick, Nora; Yermakov, Sander; Karner, Paul

2017-04-01

Continuous prophylaxis for patients with hemophilia B requires frequent injections that are burdensome and that may lead to suboptimal adherence and outcomes. Hence, therapies requiring less-frequent injections are needed. In the absence of head-to-head comparisons, this study compared the first extended-half-life-recombinant factor IX (rFIX) product-recombinant factor IX Fc fusion protein (rFIXFc)-with conventional rFIX products based on annualized bleed rates (ABRs) and factor consumption reported in studies of continuous prophylaxis. This study compared ABRs and weekly factor consumption rates in clinical studies of continuous prophylaxis treatment with rFIXFc and conventional rFIX products (identified by systematic literature review) in previously-treated adolescents and adults with moderate-to-severe hemophilia B. Meta-analysis was used to pool ABRs reported for conventional rFIX products for comparison. Comparisons of weekly factor consumption were based on the mean, reported or estimated from the mean dose per injection. Five conventional rFIX studies (injections 1 to >3 times/week) met the criteria for comparison with once-weekly rFIXFc reported by the B-LONG study. The pooled mean ABR for conventional rFIX was slightly higher than but comparable to rFIXFc (difference=0.71; p = 0.210). Weekly factor consumption was significantly lower with rFIXFc than in conventional rFIX studies (difference in means = 42.8-74.5 IU/kg/week [93-161%], p < 0.001). Comparisons of clinical study results suggest weekly injections with rFIXFc result in similar bleeding rates and significantly lower weekly factor consumption compared with more-frequently-injected conventional rFIX products. The real-world effectiveness of rFIXFc may be higher based on results from a model of the impact of simulated differences in adherence.

Ethylene Response Factors Are Controlled by Multiple Harvesting Stresses in Hevea brasiliensis

PubMed Central

Putranto, Riza-Arief; Duan, Cuifang; Kuswanhadi; Chaidamsari, Tetty; Rio, Maryannick; Piyatrakul, Piyanuch; Herlinawati, Eva; Pirrello, Julien; Dessailly, Florence; Leclercq, Julie; Bonnot, François; Tang, Chaorong; Hu, Songnian; Montoro, Pascal

2015-01-01

Tolerance of recurrent mechanical wounding and exogenous ethylene is a feature of the rubber tree. Latex harvesting involves tapping of the tree bark and ethephon is applied to increase latex flow. Ethylene is an essential element in controlling latex production. The ethylene signalling pathway leads to the activation of Ethylene Response Factor (ERF) transcription factors. This family has been identified in Hevea brasiliensis. This study set out to understand the regulation of ERF genes during latex harvesting in relation to abiotic stress and hormonal treatments. Analyses of the relative transcript abundance were carried out for 35 HbERF genes in latex, in bark from mature trees and in leaves from juvenile plants under multiple abiotic stresses. Twenty-one HbERF genes were regulated by harvesting stress in laticifers, revealing an overrepresentation of genes in group IX. Transcripts of three HbERF-IX genes from HbERF-IXc4, HbERF-IXc5 and HbERF-IXc6 were dramatically accumulated by combining wounding, methyl jasmonate and ethylene treatments. When an ethylene inhibitor was used, the transcript accumulation for these three genes was halted, showing ethylene-dependent induction. Subcellular localization and transactivation experiments confirmed that several members of HbERF-IX are activator-type transcription factors. This study suggested that latex harvesting induces mechanisms developed for the response to abiotic stress. These mechanisms probably depend on various hormonal signalling pathways. Several members of HbERF-IX could be essential integrators of complex hormonal signalling pathways in Hevea. PMID:25906196

Immunosuppressive effects of factor IX products: an in vitro study.

PubMed

Grosset, A B; McGregor, J R; Samlowski, W E; Rodgers, G M

1999-11-01

The effects of a recombinant factor IX product (BeneFix), and of five plasma-derived factor IX products, AlphaNine, Immunine, Konyne, Mononine and Replinine on in vitro peripheral blood mononuclear cell (PBMC) immune function were compared in a blinded study. We assessed the effects of these products on Con-A-induced lymphocyte proliferation and interleukin-2 and interleukin-10 secretion, expression of lymphocyte activation markers, and nitric oxide secretion by stimulated mouse peritoneal macrophages. At 1 mL-1 for 48 h, Konyne reduced Con-A-induced mitogenesis by 50% (P < 0.05); AlphaNine, Mononine and BeneFix had no effect. At 10 IU mL-1, Con-A-induced mi- togenesis was at control levels with Mononine and BeneFix, but was reduced to <15% (P < 0.05) with each of the other products. IL-2 and IL-10 secretion by Con-A-stimulated lymphocytes was also markedly depressed by all the products tested except Mononine and BeneFix. Dialysis of these products did not substantially affect these results. Flow cytometric analysis of lymphocyte activation markers following Con-A stimulation showed that Konyne also decreased IL-2 receptor alpha and beta chain (CD25 and CD122) induction on PBMC. Konyne also inhibited nitric oxide secretion to levels <18% of controls. These results indicate that certain factor IX products, including some of purported higher purity, substantially depress in vitro immune function. The importance of these findings to in vivo immune function in haemophilia B patients remains to be established.

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.

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

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.

Coagulation Testing in the Core Laboratory.

PubMed

Winter, William E; Flax, Sherri D; Harris, Neil S

2017-11-08

Primary hemostasis begins with endothelial injury. VWF, produced by endothelial cells, binds to platelets and links them to subendothelial collagen. Platelet-derived ADP and thromboxane activate non-adhered platelets via their GPIIb/IIIa receptors, allowing these platelets to participate in platelet aggregation. Secondary hemostasis is initiated with the binding of factor VII to extravascular tissue factor (TF). Factors II, VII, IX and X are vitamin K-dependent factors. The role of vitamin K is to assist in the addition of gamma carboxylate groups to glutamic acids in the "GLA" domains of these factors.In vitro the intrinsic pathway is initiated when fresh whole blood is placed in a glass tube. The negative charge of the glass initiates the "contact pathway" where FXII is activated and then FXIa cleaves FIX to FIXa. The extrinsic pathway is triggered when tissue factor, phospholipid and calcium are added to plasma anticoagulated with citrate. In vitro, FVII is activated to FVIIa, and TF-FVIIa preferentially converts FX to FXa activating the common pathway.The prothrombin time is commonly used to monitor warfarin anticoagulant therapy. To correct for differences in reagent and instrument, the international normalized ratio was developed to improve standardization of PT reporting globally. The activated partial thromboplastin time (aPTT) is used to evaluate the intrinsic and common pathways of coagulation. The aPTT is useful clinically as a screening test for inherited and acquired factor deficiencies as well as to monitor unfractionated heparin therapy although the anti-Xa assay is now the preferred measure of the effects of unfractionated heparin. The Clauss assay is the most commonly performed fibrinogen assay and uses diluted plasma where clotting is initiated with a high concentration of reagent thrombin.The mixing study assists in the assessment of an abnormally prolonged PT or aPTT. An equal volume of citrated patient plasma is mixed with normal pooled plasma and the PT or aPTT are repeated on the 1:1 mix. Factor activity assays are most commonly performed as a one-stage assay. The patient's citrated plasma is diluted and mixed 1-to-1 with a single factor-deficient substrate plasma. A PT or aPTT is performed on the above mix, depending on the factor being tested.Factor inhibitors are antibodies that are most commonly diagnosed in male patients with severe hemophilia A (FVIII deficiency) where they are induced by factor replacement therapy.Factor inhibitors can also appear in the form of spontaneous autoantibodies in both male and female individuals who were previously well. This is an autoimmune condition called "acquired hemophilia."Most coagulation laboratories can measure the plasma concentration of VWF protein (VWF antigen) by an immunoturbidimetric technique. Testing the functional activity of VWF, utilizes the drug ristocetin.The state of multimerization of VWF is important and is assessed by electrophoresis on agarose gels. Type 2a and 2b VWD are associated with the lack of intermediate- and high molecular weight multimers.The antiphospholipid syndrome (APLS) is an acquired autoimmune phenomenon associated with an increased incidence of both venous and arterial thromboses, as well as fetal loss. Typically, there is a paradoxical prolongation of the aPTT in the absence of any clinical features of bleeding. This is the so-called "lupus anticoagulant (LA) effect." The laboratory definition of the APLS requires the presence of either a "lupus anticoagulant" or a persistent titer of antiphospholipid antibodies.There are now 2 broad classes of direct-acting oral anticoagulants (DOACs): [1] The oral direct thrombin inhibitors (DTIs) such as dabigatran; and [2] The oral direct factor Xa inhibitors such as rivaroxaban and apixaban. The PT and aPTT are variably affected by the DOACs and are generally unhelpful in monitoring their concentrations. Most importantly, a normal PT or aPTT does NOT exclude the presence of any of the DOACs. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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

Immunohistochemical detection of osteopontin in advanced head-and-neck cancer: prognostic role and correlation with oxygen electrode measurements, hypoxia-inducible-factor-1alpha-related markers, and hemoglobin levels.

PubMed

Bache, Matthias; Reddemann, Rolf; Said, Harun M; Holzhausen, Hans-Jürgen; Taubert, Helge; Becker, Axel; Kuhnt, Thomas; Hänsgen, Gabriele; Dunst, Jürgen; Vordermark, Dirk

2006-12-01

The tumor-associated glycoprotein osteopontin (OPN) is discussed as a plasma marker of tumor hypoxia. However, the association of immunohistochemical OPN expression in tumor sections with tumor oxygenation parameters (HF5, median pO(2)), the hypoxia-related markers hypoxia-inducible factor-1alpha (HIF-1alpha) and carbonic anhydrase IX (CAIX), or hemoglobin and systemic vascular endothelial growth factor (VEGF) levels has not been investigated. Tumor tissue sections of 34 patients with advanced head-and-neck cancer treated with radiotherapy were assessed by immunochemistry for the expression of OPN, HIF-1alpha, and CA IX. Relationship of OPN expression with tumor oxygenation parameters (HF5, median pO(2)), HIF-1alpha and CA IX expression, hemoglobin and serum VEGF level, and clinical parameters was studied. Bivariate analysis showed a significant correlation of positive OPN staining with low hemoglobin level (p = 0.02), high HIF-1alpha expression (p = 0.02), and high serum vascular endothelial growth factor level (p = 0.02) for advanced head-and-neck cancer. Furthermore, considering the 31 Stage IV patients, the median pO(2) correlated significantly with the OPN expression (p = 0.02). OPN expression alone had only a small impact on prognosis. However, in a univariate Cox proportional hazard regression model, the expression of either OPN or HIF-1alpha or CA IX was associated with a 4.1-fold increased risk of death (p = 0.02) compared with negativity of all three markers. Osteopontin expression detected immunohistochemically is associated with oxygenation parameters in advanced head-and-neck cancer. When the results of OPN, HIF-1alpha, and CA IX immunohistochemistry are combined into a hypoxic profile, a strong and statistically significant impact on overall survival is found.

Immunohistochemical detection of osteopontin in advanced head-and-neck cancer: Prognostic role and correlation with oxygen electrode measurements, hypoxia-inducible-factor-1{alpha}-related markers, and hemoglobin levels

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

Bache, Matthias; Reddemann, Rolf; Institute of Pathology, Martin-Luther-University Halle-Wittenberg, Halle

2006-12-01

Purpose: The tumor-associated glycoprotein osteopontin (OPN) is discussed as a plasma marker of tumor hypoxia. However, the association of immunohistochemical OPN expression in tumor sections with tumor oxygenation parameters (HF5, median pO{sub 2}), the hypoxia-related markers hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) and carbonic anhydrase IX (CAIX), or hemoglobin and systemic vascular endothelial growth factor (VEGF) levels has not been investigated. Methods and Materials: Tumor tissue sections of 34 patients with advanced head-and-neck cancer treated with radiotherapy were assessed by immunochemistry for the expression of OPN, HIF-1{alpha}, and CA IX. Relationship of OPN expression with tumor oxygenation parameters (HF5, median pO{sub 2}), HIF-1{alpha}more » and CA IX expression, hemoglobin and serum VEGF level, and clinical parameters was studied. Results: Bivariate analysis showed a significant correlation of positive OPN staining with low hemoglobin level (p = 0.02), high HIF-1{alpha} expression (p = 0.02), and high serum vascular endothelial growth factor level (p = 0.02) for advanced head-and-neck cancer. Furthermore, considering the 31 Stage IV patients, the median pO{sub 2} correlated significantly with the OPN expression (p = 0.02). OPN expression alone had only a small impact on prognosis. However, in a univariate Cox proportional hazard regression model, the expression of either OPN or HIF-1{alpha} or CA IX was associated with a 4.1-fold increased risk of death (p = 0.02) compared with negativity of all three markers. Conclusion: Osteopontin expression detected immunohistochemically is associated with oxygenation parameters in advanced head-and-neck cancer. When the results of OPN, HIF-1{alpha}, and CA IX immunohistochemistry are combined into a hypoxic profile, a strong and statistically significant impact on overall survival is found.« less

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.

Of von Willebrand factor and platelets.

PubMed

Bryckaert, Marijke; Rosa, Jean-Philippe; Denis, Cécile V; Lenting, Peter J

2015-01-01

Hemostasis and pathological thrombus formation are dynamic processes that require multiple adhesive receptor-ligand interactions, with blood platelets at the heart of such events. Many studies have contributed to shed light on the importance of von Willebrand factor (VWF) interaction with its platelet receptors, glycoprotein (GP) Ib-IX-V and αIIbβ3 integrin, in promoting primary platelet adhesion and aggregation following vessel injury. This review will recapitulate our current knowledge on the subject from the rheological aspect to the spatio-temporal development of thrombus formation. We will also discuss the signaling events generated by VWF/GPIb-IX-V interaction, leading to platelet activation. Additionally, we will review the growing body of evidence gathered from the recent development of pathological mouse models suggesting that VWF binding to GPIb-IX-V is a promising target in arterial and venous pathological thrombosis. Finally, the pathological aspects of VWF and its impact on platelets will be addressed.

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.

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.

Factor VIII-bypassing activity of bovine tissue factor using the canine hemophilic model.

PubMed Central

O'Brien, D P; Giles, A R; Tate, K M; Vehar, G A

1988-01-01

The bleeding disorder of hemophilia A currently treated by replacement therapy of the missing coagulation factor, factor VIII, is frequently complicated by the development of neutralizing antibodies. The therapeutic potential of attenuated forms of the lipid-associated glycoprotein tissue factor, a known initiator of coagulation, was investigated as a factor VIII-by-passing activity. The protein moiety of tissue factor (Apo-TF) was partially purified and exhibited minimal procoagulant activity before relipidation in vitro. In pilot studies, Apo-TF injection into rabbits previously anticoagulated with an antibody to factor VIII was found to have a procoagulant effect. The efficacy of the material was further demonstrated when injection of Apo-TF in hemophilic dogs resulted in a normalization of the cuticle bleeding time. Little or no change in the blood parameters associated with disseminated intravascular coagulation was observed at lower doses, although mild to moderate effects were seen at higher doses. These data suggest a novel role for Apo-TF preparations as a potential therapeutic agent for hemophiliacs with antibodies to factor VIII once the potential thrombogenicity of such materials is evaluated. Images PMID:3134399

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.

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.

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

Motives and periods in Bianchi IX gravity models

NASA Astrophysics Data System (ADS)

Fan, Wentao; Fathizadeh, Farzad; Marcolli, Matilde

2018-05-01

We show that, when considering the anisotropic scaling factors and their derivatives as affine variables, the coefficients of the heat-kernel expansion of the Dirac-Laplacian on SU(2) Bianchi IX metrics are algebro-geometric periods of motives of complements in affine spaces of unions of quadrics and hyperplanes. We show that the motives are mixed Tate and we provide an explicit computation of their Grothendieck classes.

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.

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.

Homogeneous, anisotropic three-manifolds of topologically massive gravity

NASA Astrophysics Data System (ADS)

Nutku, Y.; Baekler, P.

1989-10-01

We present a new class of exact solutions of Deser, Jackiw, and Templeton's theory (DJT) of topologically massive gravity which consists of homogeneous, anisotropic manifolds. In these solutions the coframe is given by the left-invariant 1-forms of 3-dimensional Lie algebras up to constant scale factors. These factors are fixed in terms of the DJT coupling constant μ which is the constant of proportionality between the Einstein and Cotton tensors in 3-dimensions. Differences between the scale factors result in anisotropy which is a common feature of topologically massive 3-manifolds. We have found that only Bianchi Types VI, VIII, and IX lead to nontrivial solutions. Among these, a Bianchi Type IX, squashed 3-sphere solution of the Euclideanized DJT theory has finite action. Bianchi Type VIII, IX solutions can variously be embedded in the de Sitter/anti-de Sitter space. That is, some DJT 3-manifolds that we shall present here can be regarded as the basic constituent of anti-de Sitter space which is the ground state solution in higher dimensional generalization of Einstein's general relativity.

Homogeneous, anisotropic three-manifolds of topologically massive gravity

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

Nutku, Y.; Baekler, P.

1989-10-01

We present a new class of exact solutions of Deser, Jackiw, and Templeton's theory (DJT) of topologically massive gravity which consists of homogeneous, anisotropic manifolds. In these solutions the coframe is given by the left-invariant 1-forms of 3-dimensional Lie algebras up to constant scale factors. These factors are fixed in terms of the DJT coupling constant {mu}m which is the constant of proportionality between the Einstein and Cotton tensors in 3-dimensions. Differences between the scale factors result in anisotropy which is a common feature of topologically massive 3-manifolds. We have found that only Bianchi Types VI, VIII, and IX leadmore » to nontrivial solutions. Among these, a Bianchi Type IX, squashed 3-sphere solution of the Euclideanized DJT theory has finite action, Bianchi Type VIII, IX solutions can variously be embedded in the de Sitter/anti-de Sitter space. That is, some DJT 3-manifolds that we shall present here can be regarded as the basic constitent of anti-de Sitter space which is the ground state solution in higher dimensional generalizations of Einstein's general relativity. {copyright} 1989 Academic Press, Inc.« less

Systemic delivery of factor IX messenger RNA for protein replacement therapy

PubMed Central

Ramaswamy, Suvasini; Tonnu, Nina; Tachikawa, Kiyoshi; Limphong, Pattraranee; Vega, Jerel B.; Karmali, Priya P.; Chivukula, Pad; Verma, Inder M.

2017-01-01

Safe and efficient delivery of messenger RNAs for protein replacement therapies offers great promise but remains challenging. In this report, we demonstrate systemic, in vivo, nonviral mRNA delivery through lipid nanoparticles (LNPs) to treat a Factor IX (FIX)-deficient mouse model of hemophilia B. Delivery of human FIX (hFIX) mRNA encapsulated in our LUNAR LNPs results in a rapid pulse of FIX protein (within 4–6 h) that remains stable for up to 4–6 d and is therapeutically effective, like the recombinant human factor IX protein (rhFIX) that is the current standard of care. Extensive cytokine and liver enzyme profiling showed that repeated administration of the mRNA–LUNAR complex does not cause any adverse innate or adaptive immune responses in immune-competent, hemophilic mice. The levels of hFIX protein that were produced also remained consistent during repeated administrations. These results suggest that delivery of long mRNAs is a viable therapeutic alternative for many clotting disorders and for other hepatic diseases where recombinant proteins may be unaffordable or unsuitable. PMID:28202722

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

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.

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.

The Role of Factor XIa (FXIa) Catalytic Domain Exosite Residues in Substrate Catalysis and Inhibition by the Kunitz Protease Inhibitor Domain of Protease Nexin 2*

PubMed Central

Su, Ya-Chi; Miller, Tara N.; Navaneetham, Duraiswamy; Schoonmaker, Robert T.; Sinha, Dipali; Walsh, Peter N.

2011-01-01

To select residues in coagulation factor XIa (FXIa) potentially important for substrate and inhibitor interactions, we examined the crystal structure of the complex between the catalytic domain of FXIa and the Kunitz protease inhibitor (KPI) domain of a physiologically relevant FXIa inhibitor, protease nexin 2 (PN2). Six FXIa catalytic domain residues (Glu98, Tyr143, Ile151, Arg3704, Lys192, and Tyr5901) were subjected to mutational analysis to investigate the molecular interactions between FXIa and the small synthetic substrate (S-2366), the macromolecular substrate (factor IX (FIX)) and inhibitor PN2KPI. Analysis of all six Ala mutants demonstrated normal Km values for S-2366 hydrolysis, indicating normal substrate binding compared with plasma FXIa; however, all except E98A and K192A had impaired values of kcat for S-2366 hydrolysis. All six Ala mutants displayed deficient kcat values for FIX hydrolysis, and all were inhibited by PN2KPI with normal values of Ki except for K192A, and Y5901A, which displayed increased values of Ki. The integrity of the S1 binding site residue, Asp189, utilizing p-aminobenzamidine, was intact for all FXIa mutants. Thus, whereas all six residues are essential for catalysis of the macromolecular substrate (FIX), only four (Tyr143, Ile151, Arg3704, and Tyr5901) are important for S-2366 hydrolysis; Glu98 and Lys192 are essential for FIX but not S-2366 hydrolysis; and Lys192 and Tyr5901 are required for both inhibitor and macromolecular substrate interactions. PMID:21778227

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.

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.

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

Additional Prognostic Value of SUVmax Measured by F-18 FDG PET/CT over Biological Marker Expressions in Surgically Resected Cervical Cancer Patients.

PubMed

Yun, Man Soo; Kim, Seong-Jang; Pak, Kyoungjune; Lee, Chang Hun

2015-01-01

We compared the prognostic ability of the maximum standardized uptake value (SUVmax) and various biological marker expressions to predict recurrence in patients with surgically resected cervical cancer. A retrospective review identified 60 patients with cervical cancer who received [18F]fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) at the time of the diagnosis of cancer. The SUVmax, expressions of carbonic anhydrase-IX (CA-IX), glucose transporter 1 (GLUT-1), and vascular endothelial growth factor (VEGF), and known prognostic factors were investigated. The median follow-up time was 22.2 months (range 3.4-43.1 months). Using univariate analyses, the stage (stage II, p = 0.0066), SUVmax (> 6, p = 0.027), parametrial involvement (p < 0.0001), and positivity for CA-IX (p = 0.0191) were associated with recurrences of cervical cancer. With the Cox proportional hazard regression model, the SUVmax was a potent predictor for disease-free survival (DFS). Although CA-IX expression was related to DFS in the current study, the potent predictor for DFS was SUVmax. Therefore, SUVmax is of greater prognostic value than biological marker expression in patients with surgically resected cervical cancer. © 2015 S. Karger GmbH, Freiburg.

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.).

White light-informed optical properties improve ultrasound-guided fluorescence tomography of photoactive protoporphyrin IX

NASA Astrophysics Data System (ADS)

Flynn, Brendan P.; DSouza, Alisha V.; Kanick, Stephen C.; Davis, Scott C.; Pogue, Brian W.

2013-04-01

Subsurface fluorescence imaging is desirable for medical applications, including protoporphyrin-IX (PpIX)-based skin tumor diagnosis, surgical guidance, and dosimetry in photodynamic therapy. While tissue optical properties and heterogeneities make true subsurface fluorescence mapping an ill-posed problem, ultrasound-guided fluorescence-tomography (USFT) provides regional fluorescence mapping. Here USFT is implemented with spectroscopic decoupling of fluorescence signals (auto-fluorescence, PpIX, photoproducts), and white light spectroscopy-determined bulk optical properties. Segmented US images provide a priori spatial information for fluorescence reconstruction using region-based, diffuse FT. The method was tested in simulations, tissue homogeneous and inclusion phantoms, and an injected-inclusion animal model. Reconstructed fluorescence yield was linear with PpIX concentration, including the lowest concentration used, 0.025 μg/ml. White light spectroscopy informed optical properties, which improved fluorescence reconstruction accuracy compared to the use of fixed, literature-based optical properties, reduced reconstruction error and reconstructed fluorescence standard deviation by factors of 8.9 and 2.0, respectively. Recovered contrast-to-background error was 25% and 74% for inclusion phantoms without and with a 2-mm skin-like layer, respectively. Preliminary mouse-model imaging demonstrated system feasibility for subsurface fluorescence measurement in vivo. These data suggest that this implementation of USFT is capable of regional PpIX mapping in human skin tumors during photodynamic therapy, to be used in dosimetric evaluations.

Investigations on photolon-and porphyrin-doped sol-gel fiberoptic coatings for laser-assisted applications in medicine

NASA Astrophysics Data System (ADS)

Bindig, U.; Ulatowska-Jarza, A.; Kopaczynska, M.; Müller, G.; Podbielska, H.

2008-01-01

In view of laser-assisted medical applications, the construction of silica-based sol-gel fiberoptic sensors based on photolon (Ph) and protoporphyrin IX (PP IX) is discussed. Electron microscopy and AFM were used to characterize the silica sol-gel coatings. AFM measurements indicate a change in the surface porosity. The PP IX-based sensors were constructed as a one-layer optode as well as a multilayered structure. An additional hybrid sensor made up of alternate layers of PP IX-and Ph-doped sol-gel was also constructed and examined. Sol-gel matrices were prepared from silicate precursor tetraethylorthosilicate (TEOS) mixed with ethanol in acid-catalyzed hydrolysis. The carrier matrices of photosensitive dyes were produced with factor R = 20, where R denotes the ratio of solvent moles (ethanol) to the number of TEOS moles. A multilayered coating was built up using the reverse-dipping technique. The overall coating thickness was determined by electron microscopy. Doped sol-gels with different PP IX concentrations were used to produce fiberoptic coatings. The film optodes with a different number of layers were examined by fluorescence spectroscopy. It was found that photolon and protoporphyrin IX entrapped in sol-gel preserve their chemical reactivity and have contact with the external environment. The hybrid sensor demonstrated clear fluorescence and a reversible behavior in gaseous environments.

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.

Biodistribution and photodynamic effect of protoporphyrin IX in rat urinary bladders after intravesical instillation of 5-aminolaevulinic acid

NASA Astrophysics Data System (ADS)

Chang, Shi-Chung; MacRobert, Alexander J.; Bown, Stephen G.

1995-03-01

Photodynamic therapy (PDT) has considerable potential for the treatment of superficial bladder neoplasia. Complications such as scarring of the detrusor muscle and prolonged cutaneous photosensitivity may be reduced by using the new photosensitizer precursor, 5- aminolaevulinic acid (ALA). After instillation of ALA, the concentration, pH, and time of bladder retention of ALA solution were found to be the key factors to a satisfactory PpIX buildup in the mucosa. The optimum PpIX fluorescence intensity ratio between mucosa and muscle layer is 10 to 1 with a pH 5.5, 1% ALA solution retained for 5 hours. Higher concentration resulted in more mucosal PpIX formation, but less selectivity. Unbuffered ALA was unsuitable for bladder instillation. Two days after laser treatment with 25 J/cm2 at 630 nm with optimal sensitization, typical histological findings were urothelial sloughing and lamina propria edema without obvious muscle damage. After 7 days, recovery of the urothelium was almost complete and fibroblast infiltration was minimal. ALA induced PpIX after bladder instillation may be an appropriate photosensitizer for future management of superficial bladder cancer.

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.

Ares I-X Flight Test Development Challenges and Success Factors

NASA Technical Reports Server (NTRS)

Askins, Bruce; Davis, Steve; Olsen, Ronald; Taylor, James

2010-01-01

The NASA Constellation Program's Ares I-X rocket launched successfully on October 28, 2009 collecting valuable data and providing risk reduction for the Ares I project. The Ares I-X mission was formulated and implemented in less than four years commencing with the Exploration Systems Architecture Study in 2005. The test configuration was founded upon assets and processes from other rocket programs including Space Shuttle, Atlas, and Peacekeeper. For example, the test vehicle's propulsion element was a Shuttle Solid Rocket Motor. The Ares I-X rocket comprised a motor assembly, mass and outer mold line simulators of the Ares I Upper Stage, Orion Spacecraft and Launch Abort System, a roll control system, avionics, and other miscellaneous components. The vehicle was 327 feet tall and weighed approximately 1,800,000 pounds. During flight the rocket reached a maximum speed of Mach 4.8 and an altitude of 150,000 feet. The vehicle demonstrated staging at 130,000 feet, tested parachutes for recovery of the motor, and utilized approximately 900 sensors for data collection. Developing a new launch system and preparing for a safe flight presented many challenges. Specific challenges included designing a system to withstand the environments, manufacturing large structures, and re-qualifying heritage hardware. These and other challenges, if not mitigated, may have resulted in test cancellation. Ares I-X succeeded because the mission was founded on carefully derived objectives, led by decisive and flexible management, implemented by an exceptionally talented and dedicated workforce, and supported by a thorough independent review team. Other major success factors include the use of proven heritage hardware, a robust System Integration Laboratory, multi-NASA center and contractor team, concurrent operations, efficient vehicle assembly, effective risk management, and decentralized element development with a centralized control board. Ares I-X was a technically complex test that required creative thinking, risk taking, and a passion to succeed.

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.

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

Double-stranded RNA innate immune response activation from long-term adeno-associated virus vector transduction.

PubMed

Shao, Wenwei; Earley, Lauriel F; Chai, Zheng; Chen, Xiaojing; Sun, Junjiang; He, Ting; Deng, Meng; Hirsch, Matthew L; Ting, Jenny; Samulski, R Jude; Li, Chengwen

2018-06-21

Data from clinical trials for hemophilia B using adeno-associated virus (AAV) vectors have demonstrated decreased transgenic coagulation factor IX (hFIX) expression 6-10 weeks after administration of a high vector dose. While it is likely that capsid-specific cytotoxic T lymphocytes eliminate vector-transduced hepatocytes, thereby resulting in decreased hFIX, this observation is not intuitively consistent with restored hFIX levels following prednisone application. Although the innate immune response is immediately activated following AAV vector infection via TLR pathways, no studies exist regarding the role of the innate immune response at later time points after AAV vector transduction. Herein, activation of the innate immune response in cell lines, primary human hepatocytes, and hepatocytes in a human chimeric mouse model was observed at later time points following AAV vector transduction. Mechanistic analysis demonstrated that the double-stranded RNA (dsRNA) sensor MDA5 was necessary for innate immune response activation and that transient knockdown of MDA5, or MAVS, decreased IFN-β expression while increasing transgene production in AAV-transduced cells. These results both highlight the role of the dsRNA-triggered innate immune response in therapeutic transgene expression at later time points following AAV transduction and facilitate the execution of effective strategies to block the dsRNA innate immune response in future clinical trials.

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.

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.

Platelet interactions in thrombosis.

PubMed

Andrews, Robert K; Gardiner, Elizabeth E; Shen, Yang; Berndt, Michael C

2004-01-01

Patho/physiological platelet aggregate (thrombus) formation is initiated by engagement of platelet surface receptors, glycoprotein (GP)Ib-IX-V and GPVI that bind von Willebrand factor or collagen. Although beneficial in response to vascular injury by preventing blood loss (haemostasis), platelet aggregation in a sclerotic coronary artery or other diseased blood vessel (thrombosis) can cause thrombotic diseases like heart attack and stroke. At the molecular level, ligand interactions with GPIb-IX-V or GPVI trigger signalling responses, including elevation of cytosolic Ca2+, dissociation of calmodulin from their cytoplasmic domains, cytoskeletal actin-filament rearrangements, activation of src-family kinases or PI 3-kinase, and 'inside-out' activation of the integrin, alphaIIbbeta3 (GPIIb-llla), that binds von Willebrand factor or fibrinogen and mediates platelet aggregation. Furthermore, emerging evidence supports a topographical co-association of these receptors of the leucine-rich repeat family (GPIb-IX-V) and immunoglobulin superfamily (GPVI) in an adhesive cluster or 'adhesosome'. This arrangement may underlie common mechanisms of initiating thrombus formation in haemostasis or thrombotic disease.

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

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

Effect of Food, Diet and Nutrition on Military Readiness and Preparedness of Army Personnel and Dependents in a Peacetime Environment

DTIC Science & Technology

1992-08-15

SETUP 04 Jan 9. •:09 :49 Page S, ;CHRMN VAL5 US•.ER ._-, DE INm-U. C.HOWI;RIES QSýR la;1 Test Name: EWS[ Calculation Factor: 3617 Reaction Type: [RATE i1...4 00 . aWI > Z:Z A M C4 (N0)0) 40 1 W IX I,W LLS ’n +Ix 0. el IL C.) If) a 0. Oc :10 LLI 0 >- 3t b) I 04 Lý C)La > -i -i LAJ -j .9 L" +1 I LLI I C4...kI u~ 1- - S * c2z.a w wa 140 Z M 4-9a % I M aU 1 z 0 Ix (A Z el - HW ix Il- Iz I4 Sw ;w IS I l- I W W O a Z3 ~ 1--W 1. 0. S 4- A z4 Iř 3 1400 =I 1

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

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.

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.

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.

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

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.

Harnessing cellular differentiation to improve ALA-based photodynamic therapy in an artificial skin model

NASA Astrophysics Data System (ADS)

Maytin, Edward; Anand, Sanjay; Sato, Nobuyuki; Mack, Judith; Ortel, Bernhard

2005-04-01

During ALA-based photodynamic therapy (PDT), a pro-drug (aminolevulinic acid; ALA) is taken up by tumor cells and metabolically converted to a photosensitizing intermediate (protoporphyrin IX; PpIX). ALA-based PDT, while an emerging treatment modality, remains suboptimal for most cancers (e.g. squamous cell carcinoma of the skin). Many treatment failures may be largely due to insufficient conversion of ALA to PpIX within cells. We discovered a novel way to increase the conversion of ALA to PpIX, by administering agents that can drive terminal differentiation (i.e., accelerate cellular maturation). Terminally-differentiated epithelial cells show higher levels of intracellular PpIX, apparently via increased levels of a rate-limiting enzyme, coproporphyrinogen oxidase (CPO). To study these mechanisms in a three-dimensional tissue, we developed an organotypic model that mimics true epidermal physiology in a majority of respects. A line of rat epidermal keratinocytes (REKs), when grown in raft cultures, displays all the features of a fully-differentiated epidermis. Addition of ALA to the culture medium results in ALA uptake and PpIX synthesis, with subsequent death of keratinocytes upon exposure to blue light. Using this model, we can manipulate cellular differentiation via three different approaches. (1) Vitamin D, a hormone that enhances keratinocyte differentiation; (2) Hoxb13, a nuclear transcription factor that affects the genetically-controlled differentiation program of stratifying cells (3) Hyaluronan, an abundant extracellular matrix molecule that regulates epidermal differentiation. Because the raft cultures contain only a single cell type (no blood, fibroblasts, etc.) the effects of terminal differentiation upon CPO, PpIX, and keratinocyte cell death can be specifically defined.

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

[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.

Evaluation of Consequences of Dust Positioned in Southwest of Iran on Coagulant Factors

PubMed Central

Saeb, Keivan; Sarizade, Gholamreza; Khodadi, Mohammad; Biazar, Esmaeil

2013-01-01

Background: Various regions in Iran, especially the Khuzestan Province, have been covered by dust and dirt during the past two years due to environmental changes in the Middle East. We sought to evaluate the effect of these pollutants on the coagulant factors of people residing in Abadan and Khoramshahr, two major cities of Khuzestan Province. Methods: One hundred twenty-nine healthy individuals were enrolled into this study, and their prothrombin time as well as fibrinogen, platelet, and Factor VIII levels were measured before and after climate changes. Results: After climate changes, the mean prothrombin time decreased, while the fibrinogen, platelet, and Factor VIII levels rose. Conclusion: The results of this study suggest that the pollutants deployed in the Middle East can affect prothrombin time as well as fibrinogen, platelet, and Factor VII levels considerably and increase coagulant state. The pollutants can, consequently, increase the risk of cardiovascular diseases. It seems that cooperation at government levels between Iran and its neighboring countries is required to reverse desertification and avoid inaccurate usage of subterranean water resources so as to lessen air pollution. PMID:23825886

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.

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.

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.

Abnormal factor VIII coagulant antigen in patients with renal dysfunction and in those with disseminated intravascular coagulation.

PubMed Central

Weinstein, M J; Chute, L E; Schmitt, G W; Hamburger, R H; Bauer, K A; Troll, J H; Janson, P; Deykin, D

1985-01-01

Factor VIII antigen (VIII:CAg) exhibits molecular weight heterogeneity in normal plasma. We have compared the relative quantities of VIII:CAg forms present in normal individuals (n = 22) with VIII:CAg forms in renal dysfunction patients (n = 19) and in patients with disseminated intravascular coagulation (DIC; n = 7). In normal plasma, the predominant VIII: CAg form, detectable by sodium dodecyl sulfate polyacrylamide gel electrophoresis, was of molecular weight 2.4 X 10(5), with minor forms ranging from 8 X 10(4) to 2.6 X 10(5) D. A high proportion of VIII:CAg in renal dysfunction patients, in contrast, was of 1 X 10(5) mol wt. The patients' high 1 X 10(5) mol wt VIII: CAg level correlated with increased concentrations of serum creatinine, F1+2 (a polypeptide released upon prothrombin activation), and with von Willebrand factor. Despite the high proportion of the 1 X 10(5) mol wt VIII:CAg form, which suggests VIII:CAg proteolysis, the ratio of Factor VIII coagulant activity to total VIII:CAg concentration was normal in renal dysfunction patients. These results could be simulated in vitro by thrombin treatment of normal plasma, which yielded similar VIII:CAg gel patterns and Factor VIII coagulant activity to antigen ratios. DIC patients with high F1+2 levels but no evidence of renal dysfunction had an VIII:CAg gel pattern distinct from renal dysfunction patients. DIC patients had elevated concentrations of both the 1 X 10(5) and 8 X 10(4) mol wt VIII:CAg forms. We conclude that an increase in a particular VIII:CAg form correlates with the severity of renal dysfunction. The antigen abnormality may be the result of VIII:CAg proteolysis by a thrombinlike enzyme and/or prolonged retention of proteolyzed VIII:CAg fragments. Images PMID:3932466

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.

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.

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.

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.

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.

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

Cellular pH and PI3K signaling as determinants of Protoporphyrin IX conversion and ALA PDT response

NASA Astrophysics Data System (ADS)

Anderson, Michael; El-Hamidi, Hamid; Celli, Jonathan

2018-02-01

ALA PDT is a FDA approved cancer treatment. The general model is that excess exogenous ALA is eventually converted to the active photosensitizer, PpIX, and accumulates PpIX to concentrations well above baseline. This accumulation, however, varies considerable from person to person and even intra-tumorally due to a high number of factors that are involved. Due to this there is an increasing desire to pair ALA PDT with other treatments to enhance the efficacy of PDT. This idea itself isn't new as the labs of Bin Chen and Edward Maytin have a long history of using biology to enhance PpIX accumulation. The PI3K pathway is a long-studied cancer treatment target due to it being one of the most ubiquitous over expressed pathways in cancer and that many treatments have demonstrated enhanced efficacy upon PI3K inhibition. In this paper we show that the PI3K pathway inhibitor, LY294002, alters PpIX accumulation in cells (decreased for A431 and increases for Panc-1 and Panc-1 OR) and significantly increases the efficacy of ALA PDT in every case for both monolayer and spheroid cultures. Additionally, we show that PDT treatments using the nonendogenous photosensitizer, verteporfin, also have enhanced efficacy upon PI3K inhibition. Beyond the treatment synergy of PI3K inhibition and PDT, this work presents a cell pairing model that is perfect to study the previously, to our knowledge, undocumented connection between the PI3K pathway and PpIX accumulation.

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.

Evaluation of thrombogenicity of beta-propiolactone/ultraviolet (beta-PL/UV) treated PPSB in chimpanzees

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

Kotitschke, R.; Stephan, W.; Prince, A.M.

1983-05-01

The thrombogenicity of beta-PL/UV-treated PPSB (factor IX concentrate) was evaluated in chimpanzees. PPSB isolated from beta-propiolactone-treated and UV-irradiated plasma was injected into chimpanzees at a dose of approximately 100 units/kg body weight. An FDA licensed PPSB preparation served as the negative control, and a preparation containing activated as well as precursor clotting factors served as the positive control. 15 minutes, 1 h, 4 h, and 24 h after the PPSB application the following parameters were determined in the chimpanzee blood: factors II, VII, IX, X, VIII, fibrinogen, AT III, thrombin coagulase, Quick value, APTT and platelet count. Neither the untreatedmore » control preparation, nor the PPSB isolated from beta-propiolactone-treated and UV-irradiated plasma, showed signs of thrombogenicity in the chimpanzee model. The positive control indicated that the chimpanzee is a suitable model for the thrombogenicity testing of activated clotting factors.« less

[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.

The influence of prophylactic factor VIII in severe hemophilia A

PubMed Central

Gissel, Matthew; Whelihan, Matthew F; Ferris, Lauren A; Mann, Kenneth G; Rivard, Georges E; Brummel-Ziedins, Kathleen E

2013-01-01

Introduction Hemophilia A individuals displaying a similar genetic defect have heterogeneous clinical phenotypes. Aim To evaluate the underlying effect of exogenous factor (f)VIII on tissue factor (Tf)-initiated blood coagulation in severe hemophilia utilizing both empirical and computational models. Methods We investigated twenty-five clinically severe hemophilia A patients. All individuals were on fVIII prophylaxis and had not received fVIII from 0.25 to 4 days prior to phlebotomy. Coagulation was initiated by the addition of Tf to contact-pathway inhibited whole blood ± an anti-fVIII antibody. Aliquots were quenched over 20 min and analyzed for thrombin generation and fibrin formation. Coagulation factor levels were obtained and used to computationally predict thrombin generation with fVIII set to either zero or its value at the time of the draw. Results Due to prophylactic fVIII, at the time of the blood draw, the individuals had fVIII levels that ranged from <1% to 22%. Thrombin generation (maximum level and rate) in both empirical and computational systems increased as the level of fVIII increased. FXIII activation rates also increased as the fVIII level increased. Upon suppression of fVIII, thrombin generation became comparable in both systems. Plasma composition analysis showed a negative correlation between bleeding history and computational thrombin generation in the absence of fVIII. Conclusion Residual prophylactic fVIII directly causes an increase in thrombin generation and fibrin cross-linking in individuals with clinically severe hemophilia A. The combination of each individual's coagulation factors (outside of fVIII) determine each individual's baseline thrombin potential and may affect bleeding risk. PMID:21899664

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.

Ixora coccinea Enhances Cutaneous Wound Healing by Upregulating the Expression of Collagen and Basic Fibroblast Growth Factor

PubMed Central

Upadhyay, Aadesh; Chattopadhyay, Pronobesh; Goyary, Danswrang; Mitra Mazumder, Papiya; Veer, Vijay

2014-01-01

Background. Ixora coccinea L. (Rubiaceae) has been documented for traditional use in hypertension, menstrual irregularities, sprain, chronic ulcer, and skin diseases. In the present study, I. coccinea was subjected to in vitro and in vivo wound healing investigation. Methods. Petroleum ether, chloroform, methanol, and water sequential I. coccinea leaves extracts were evaluated for in vitro antioxidant, antimicrobial, and fibroblast proliferation activities. The promising I. coccinea methanol extract (IxME) was screened for in vivo wound healing activity in Wistar rat using circular excision model. Wound contraction measurement, hydroxyproline quantification, and western blot for collagen type III (COL3A1), basic fibroblast growth factor (bFGF), and Smad-2, -3, -4, and -7 was performed with 7-day postoperative wound granulation tissue. Gentamicin sulfate (0.01% w/w) hydrogel was used as reference standard. Results. IxME showed the potent antimicrobial, antioxidant activities, with significant fibroblast proliferation inducing activity, as compared to all other extracts. In vivo study confirmed the wound healing accelerating potential of IxME, as evidenced by faster wound contraction, higher hydroxyproline content, and improved histopathology of granulation tissue. Western blot analysis revealed that the topical application of I. coccinea methanol extract stimulates the fibroblast growth factor and Smad mediated collagen production in wound tissue. PMID:24624303

Evolutionary pattern of mutation in the factor IX genes of great apes: How does it compare to the pattern of recent germline mutation in patients with hemophilia B?

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

Grouse, L.H.; Ketterling, R.P.; Sommer, S.S.

Most mutations causing hemophilia B have arisen within the past 150 years. By correcting for multiple biases, the underlying rates of spontaneous germline mutation have been estimated in the factor IX gene. From these rates, an underlying pattern of mutation has emerged. To determine if this pattern compares to a underlying pattern found in the great apes, sequence changes were determined in intronic regions of the factor IX gene. The following species were studied: Gorilla gorilla, Pan troglodytes (chimpanzee), Pongo pygmacus (orangutan) and Homo sapiens. Intronic sequences at least 200 bp from a splice junction were randomly chosen, amplified bymore » cross-species PCR, and sequenced. These regions are expected to be subject to little if any selective pressure. Early diverged species of Old World monkeys were also studied to help determine the direction of mutational changes. A total of 62 sequence changes were observed. Initial data suggest that the average pattern since evolution of the great apes has a paucity of transitions at CpG dinucleotides and an excess of microinsertions to microdeletions when compared to the pattern observed in humans during the past 150 years (p<.05). A larger study is in progress to confirm these results.« less

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.

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.

Functional assembly of intrinsic coagulation proteases on monocytes and platelets. Comparison between cofactor activities induced by thrombin and factor Xa

PubMed Central

1992-01-01

Generation of coagulation factor Xa by the intrinsic pathway protease complex is essential for normal activation of the coagulation cascade in vivo. Monocytes and platelets provide membrane sites for assembly of components of this protease complex, factors IXa and VIII. Under biologically relevant conditions, expression of functional activity by this complex is associated with activation of factor VIII to VIIIa. In the present studies, autocatalytic regulatory pathways operating on monocyte and platelet membranes were investigated by comparing the cofactor function of thrombin-activated factor VIII to that of factor Xa-activated factor VIII. Reciprocal functional titrations with purified human factor VIII and factor IXa were performed at fixed concentrations of human monocytes, CaCl2, factor X, and either factor IXa or factor VIII. Factor VIII was preactivated with either thrombin or factor Xa, and reactions were initiated by addition of factor X. Rates of factor X activation were measured using chromogenic substrate specific for factor Xa. The K1/2 values, i.e., concentration of factor VIIIa at which rates were half maximal, were 0.96 nM with thrombin- activated factor VIII and 1.1 nM with factor Xa-activated factor VIII. These values are close to factor VIII concentration in plasma. The Vsat, i.e., rates at saturating concentrations of factor VIII, were 33.3 and 13.6 nM factor Xa/min, respectively. The K1/2 and Vsat values obtained in titrations with factor IXa were not significantly different from those obtained with factor VIII. In titrations with factor X, the values of Michaelis-Menten coefficients (Km) were 31.7 nM with thrombin- activated factor VIII, and 14.2 nM with factor Xa-activated factor VIII. Maximal rates were 23.4 and 4.9 nM factor Xa/min, respectively. The apparent catalytic efficiency was similar with either form of factor VIIIa. Kinetic profiles obtained with platelets as a source of membrane were comparable to those obtained with monocytes. These kinetic profiles are consistent with a 1:1 stoichiometry for the functional interaction between cofactor and enzyme on the surface of monocytes and platelets. Taken together, these results indicate that autocatalytic pathways connecting the extrinsic, intrinsic, and common coagulation pathways can operate efficiently on the monocyte membrane. PMID:1613461

SU-F-T-66: Characteristics of Electron Beams From Varian Trubeam

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

Dimofte, A; Kennedy, C; Zhu, T

2016-06-15

Purpose: The purpose of this study was to compare the electron beam data between Truebeam and 2300ix Varian accelerators for percent depth dose for broad beam and small circular cutouts, cone factors, head scatter factor as a function of cone size and SSD, phantom scatter factor, blocking factor, distance factor and virtual source position. Methods: Measurements were performed for Truebeam and 2300ix Varian accelerators. The main energies used were: 6, 9, 12, 16 and 20 MeV. PDD was measured at SSD = 100 cm for open beam and small circular cutouts (r = 0.5, 1.0, 1.5, 2.0, 3.0, 4.0 andmore » 6.6cm) for different energies. Measurements to determine the head scatter factor (H) were done as a function of radius for six representative energies and five cone sizes (6, 10, 15, 20 and 25cm2). The phantom scatter factor (PSF) is defined as the ratio of blocking factor in water at reference depth and head scatter factor in air. PSF was measured as a function of radius and electron energy. Distance factor was measured for all energies and cones for three SSD’s (100, 110 and 120cm). Results: The percent depth dose (PDD) was measured for small cutouts of radius r = 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0 and 5.6cm. Blocking factor (BF) was measured for Truebeam and 2300ix accelerators, for different circular cutouts and energies for a 10×10 cone. Cone factors were compared between the two accelerators for different energies and applicator sizes. Conclusion: Cone factors measured for the two accelerator types differ by up to 5% for the largest applicator size. Blocking factors differs by up to 3%, with the largest variation for the smallest field size (0.5cm). Distance factor for different SSD’s differ by up to 4.5%.« less

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.

Investigating intermolecular forces associated with thrombus initiation using optical tweezers

NASA Astrophysics Data System (ADS)

Arya, Maneesh; Lopez, Jose A.; Romo, Gabriel M.; Dong, Jing-Fei; McIntire, Larry V.; Moake, Joel L.; Anvari, Bahman

2002-05-01

Thrombus formation occurs when a platelet membrane receptor, glycoprotein (GP) Ib-IX-V complex, binds to its ligand, von Willebrand factor (vWf), in the subendothelium or plasma. To determine which GP Ib-IX-V amino acid sequences are critical for bond formation, we have used optical tweezers to measure forces involved in the binding of vWf to GP Ib-IX-V variants. Inasmuch as GP Ib(alpha) subunit is the primary component in human GP Ib-IX-V complex that binds to vWf, and that canine GP Ib(alpha) , on the other hand, does not bind to human vWf, we progressively replaced human GP Ib(alpha) amino acid sequences with canine GP Ib(alpha) sequences to determine the sequences essential for vWf/GP Ib(alpha) binding. After measuring the adhesive forces between optically trapped, vWf-coated beads and GP Ib(alpha) variants expressed on mammalian cells, we determined that leucine- rich repeat 2 of GP Ib(alpha) was necessary for vWf/GP Ib-IX- V bond formation. We also found that deletion of the N- terminal flanking sequence and leucine-rich repeat 1 reduced adhesion strength to vWf but did not abolish binding. While divalent cations are known to influence binding of vWf, addition of 1mM CaCl2 had no effect on measured vWf/GP Ib(alpha) bond strengths.

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.

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).

Response Surface Analysis of Stochastic Network Performance

DTIC Science & Technology

1988-12-01

Bl5/32768/, B16 /65536/,P/2147483647/ XHI-IX/B 16 XALO=(IX-XHI* Bl6 )*A LEFTLO=XALO/ Bl6 FHI=XHI*A+LEFTLO IC=FHI/B1 5 IX-(((XALO-LEFTLO* Bl6 )-P)4(FHI-K*Bl5...ELSE GO TO 50 END IF GO TO 50 100 END D-5 * RANDOM NUMBER GENERATOR FUNCTION RANDOM( IX) INTEGER AP, IX,B15, B16 ,XHI ,XALOI,LEFTLO,FHI ,K DATA A/16807... Bl6 )+K IF(IX.LT.O) IX=IX+P RANDOM-FLOAT( IX) *4.656612875E-1O RETURN END * NETWORK ENTRY and * PATHSET AND CUTSET GENERATION SUBROUTINE SUBROUTINE

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 ...

Improved murine glioma detection following modified diet and photobleaching of skin PpIX fluorescence

NASA Astrophysics Data System (ADS)

Gibbs, Summer L.; O'Hara, Julia A.; Hoopes, P. Jack; Pogue, Brian W.

2007-02-01

The Aminolevulinic Acid (ALA) - Protoporphyrin IX (PpIX) system is unique in the world of photosensitizers in that the prodrug ALA is enzymatically transformed via the tissue of interest into fluorescently detectable levels of PpIX. This system can be used to monitor cellular metabolism of tumor tissue for applications such as therapy monitoring. Detecting PpIX fluorescence noninvasively has proven difficult due to the high levels of PpIX produced in the skin compared to other tissue both with and without ALA administration. In the current study, methods to decrease skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration have been examined. Use of a purified diet is found to decrease both skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration, while addition of a broad spectrum antibiotic to the water shows little effect. Following ALA administration, improved brain tumor detection is seen when skin PpIX fluorescence is photobleached via blue light prior to transmission spectroscopic measurements of tumor bearing and control animals. Both of these methods to decrease skin PpIX autofluorescence and skin PpIX fluorescence following ALA administration are shown to have a large effect on the ability to detect tumor tissue PpIX fluorescence noninvasively in vivo.

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.

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.

Hsp27 and its expression pattern in diffusely infiltrating astrocytomas.

PubMed

Mäkelä, Katri S; Haapasalo, Joonas A; Ilvesaro, Joanna M; Parkkila, Seppo; Paavonen, Timo; Haapasalo, Hannu K

2014-09-01

Heat shock protein 27 (Hsp27) is induced by cell stress conditions. In the presence of oxidative stress it functions as an antioxidant. To study the putative expression patterns and clinical significance of Hsp27, we assessed the associations between Hsp27, R132H mutation of Isocitrate dehydrogenase1 (IDH1-R132H), Hypoxia-inducible factor subunit alpha (HIF-1 alpha), Carbonic anhydrase IX (CA IX), and patient prognosis in astrocytic gliomas. Tissue micro-array samples of 295 grade II-IV astrocytomas were stained immunohistochemically for Hsp27, IDH1-R132H, HIF-1 alpha, and CA IX. We tested their relationship with clinicopathological features and patient survival. There was a significant correlation between Hsp27 expression and increasing WHO grade (p<0.001). Hsp27 expression correlated significantly with IDH1 mutation when studied within the entire cohort (p<0.001) as well as separately in WHO grade II and III tumors (p=0.006 and 0.002, respectively). IDH1 mutation and HIF-1 alpha positive staining were detected simultaneously (p<0.001). In IDH1 mutated tumors, positive HIF-1 alpha staining correlated with CA IX expression (p=0.027), whereas no such correlation was found in IDH1 non-mutated tumors. IDH1 mutation was associated with a low cell proliferation index (p=0.001) and HIF-1 alpha with increasing proliferation (p = 0.003). Hsp27 expression was associated with a shorter rate of patient survival in univariate survival analysis (p=0.001). In multivariate survival analysis, patient age, IDH1 mutation and HIF-1 alpha appeared as independent prognostic factors (p<0.000, <0.000 and 0.011 respectively) Hsp27 expression is associated with increasing WHO grade and patient prognosis in astrocytic gliomas. The results suggest that IDH1 mutation may have an effect on the expression pathways of Hsp27 and CA IX.

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.

Effect of Photon Radiations in Semi-Rigid Artificial Tissue Sensitized by Protoporphyrin IX Encapsulated with Silica Nanoparticles

NASA Astrophysics Data System (ADS)

Makhadmeh, Ghaseb N.; Aziz, Azlan Abdul; Razak, Khairunisak Abdul; Al-Akhras, M.-Ali H.

2018-02-01

This study involves the synthesis of Protoporphyrin IX (PpIX) encapsulated with Silica Nanoparticles (SiNPs) as an application for Photodynamic therapy. Semi-rigid artificial tissues with optical features similar to human tissue were used as sample materials to ascertain the efficacy of PpIX encapsulated with SiNPs. The disparity in optical characteristics (transmittance, reflectance, scattering, and absorption) of tissues treated with encapsulated PpIX and naked PpIX under light exposure (Intensity at 408 nm ~1.19 mW/cm2) was explored. The optimal exposure times required for naked PpIX and SiNPs encapsulated PpIX to engulf Red Blood Cells (RBCs) in the artificial tissue were subsequently measured. Comparative analysis showed that the encapsulated PpIX has a 91.5 % higher efficacy than naked PpIX. The results prove the applicability of PpIX encapsulated with SiNP on artificial tissue and possible use on human tissue.

Genetics Home Reference: glycogen storage disease type IX

MedlinePlus

... Health Conditions Glycogen storage disease type IX Glycogen storage disease type IX Printable PDF Open All Close ... to view the expand/collapse boxes. Description Glycogen storage disease type IX (also known as GSD IX) ...

[Factors influencing activity of oral anticoagulants. Interactions with drugs and food].

PubMed

Sawicka-Powierza, Jolanta; Rogowska-Szadkowska, Dorota; Ołtarzewska, Alicja Małgorzata; Chlabicz, Sławomir

2008-05-01

Oral anticoagulants (OAC) are commonly used as a life-long therapy in prevention of systemic embolism in patients with atrial fibrillation, valvular heart disease and prosthetic hart valves and in the primary and secondary prevention of venous thromboembolism. They are also used for the prevention of thromboembolic events in patients with acute myocardial infarction and with angina pectoris, in patients with biological hart valves and after some types of orthopaedics surgery. The International Normalized Ratio (INR) is used to evaluate the efficacy of anti-coagulant therapy. The risk of thromboembolic and haemorrhagic complications increases when the INR is out of the therapeutic range. The aim of this study was to present information about the factors influencing activity of oral anticoagulants and interactions between oral anticoagulants and drugs or food. The effect of oral anticoagulants is influenced by genetic and environmental factors such as: medicines, food, diseases and pre-existing conditions. A common mutation in the gene coding for the cytochrome P450 (CYP2C9), with one or more combinations of its polymorphisms, is responsible for the reduced warfarin requirements or for the resistance to warfarin. A mutation in the factor IX is responsible for the risk of bleeding during OAC therapy without excessive prolongation of the prothrombin time (PT). Drugs, herbs and multivitamin supplements can alter the absorption, pharmacokinetics or pharmakodynamics of OAC. Nonsteroid anti-inflammatory drugs and paracetamol in combination with OAC seem to be the most dangerous because they are available without prescription and are used without medical consultation. Patients on OAC therapy are sensitive to changing dietary intake of vitamin K, which is supplied from phylloquinones in plants or from vitamin K-containing medicines. The effect of OAC can be influenced by other existing factors like: fever, diarrhoea, alcohol abuse or physical hyperactivity. Some malignancies or other diseases like cardiac insufficiency, hyperthyroidism and hypothyroidism or hepatic dysfunction may also affect OAC therapy. This treatment requires patients and doctors to be knowledgeable about factors influencing the activity of oral anticoagulants. For this reason educational programme on OAC therapy should be conducted among patients and doctors.

[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.

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.

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)

Growth stimulation of Porphyromonas endodontalis by hemoglobin and protoporphyrin IX.

PubMed

Zerr, M A; Cox, C D; Johnson, W T; Drake, D R

2000-12-01

Porphyromonas endodontalis, like other Porphyromonas species, has a complex set of nutritional requirements. In addition to being an obligate anaerobe, the bacterium must be grown in a complex medium consisting of amino acids, reducing agents and heme compounds. P. endodontalis accumulates high concentrations of heme pigments to the extent that colonies appear black on blood agar. This accumulation of heme and the need for these compounds has been characterized as iron requirements by these species. However, in our studies, P. endodontalis demonstrated growth dependence on hemoglobin or protoporphyrin IX but not on free iron. Iron added to other heme compounds actually decreased growth stimulation by porphyrin-containing compounds. P. endodontalis actively transported free iron, but this process did not appear to be critical for growth. The maximum stimulation of growth by protoporphyrin IX, under conditions of iron deprivation, suggests that P. endodontalis requires the porphyrin moiety as a growth factor.

Encapsulation efficacy of natural and synthetic photosensitizers by silica nanoparticles for photodynamic applications.

PubMed

Makhadmeh, Ghaseb Naser; Abdul Aziz, Azlan; Abdul Razak, Khairunisak; Abu Noqta, Osama

2015-12-01

This study analysed the physical effects of Cichorium Pumilum (CP), as a natural photosensitizer (PS), and Protoporphyrin IX (PpIX), as a synthetic PS, encapsulated with silica nanoparticles (SiNPs) in photodynamic therapy. The optimum concentrations of CP and PpIX, needed to destroy Red Blood Cells (RBC), were determined and the efficacy of encapsulated CP and PpIX were compared with naked CP and PpIX was verified. The results confirmed the applicability of CP and PpIX encapsulated in SiNPs on RBCs, and established a relationship between the encapsulated CP and PpIX concentration and the time required to rupture 50% of the RBCs (t50). The CP and PpIX encapsulated in SiNPs exhibited higher efficacy compared with that of naked CP and PpIX, respectively, and CP had less efficacy compared with PpIX.

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.

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.

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.

Formation of Mg-Containing Chlorophyll Precursors from Protoporphyrin IX, δ-Aminolevulinic Acid, and Glutamate in Isolated, Photosynthetically Competent, Developing Chloroplasts 1

PubMed Central

Fufsler, Thomas P.; Castelfranco, Paul A.; Wong, Yum-Shing

1984-01-01

Intact developing chloroplasts isolated from greening cucumber (Cucumis sativus L. var Beit Alpha) cotyledons were found to contain all the enzymes necessary for the synthesis of chlorophyllide. Glutamate was converted to Mg-protoporphyrin IX (monomethyl ester) and protoclorophyllide. δ-Aminolevulinic acid and protoporphyrin IX were converted to Mg-protoporphyrin IX, Mg-protoporphyrin IX monomethyl ester, protochlorophyllide and chlorophyllide a. The conversion of δ-aminolevulinic acid or protoporphyrin IX to Mg-protoporphyrin IX (monomethyl ester) was inhibited by AMP and p-chloromercuribenzene sulfonate. Light stimulated the formation of Mg-protoporphyrin IX from all three substrates. In the case of δ-aminolevulinic acid and protoporphyrin IX, light could be replaced by exogenous ATP. In the case of glutamate, both ATP and reducing power were necessary to replace light. With all three substrates, glutamate, δ-aminolevulinic acid, and protoporphyrin IX, the stimulation of Mg-protoporphyrin IX accumulation in the light was abolished by DCMU, and this DCMU block was overcome by added ATP and reducing power. PMID:16663535

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.

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.

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...

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.

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 ...

Plasmapheresis in severe septic shock with disseminated intravascular coagulation.

PubMed

Zilow, E P; Selle, B; Zilow, G

1994-01-01

An 18-year-old female with CNS relapse of acute lymphoblastic leukemia after previous complete remission of the disease underwent chemotherapy. Due to the therapy she suffered from profound suppression of bone marrow with consecutive thrombocytopenia and leukopenia. Despite prophylactic treatment, severe septicemia occurred with septic shock, hemolysis and disseminated intravascular coagulation (DIC). As the clinical course became uncontrollable by means of conventional therapy, including broad-spectrum antibiotics, substitution of fresh frozen plasma, antithrombin III and heparin therapy, plasma exchange was used as a rescue therapy. This method succeeded in effective replacement of clotting factors and normalization of coagulation, in removal of fibrinogen degradation products and probably of toxins and shock mediators. The patient recovered from shock.

Proteins, Platelets, and Blood Coagulation at Biomaterial Interfaces

PubMed Central

Xu, Li-Chong; Bauer, James; Siedlecki, Christopher A.

2015-01-01

Blood coagulation and platelet adhesion remain major impediments to the use of biomaterials in implantable medical devices. There is still significant controversy and question in the field regarding the role that surfaces play in this process. This manuscript addresses this topic area and reports on state of the art in the field. Particular emphasis is placed on the subject of surface engineering and surface measurements that allow for control and observation of surface-mediated biological responses in blood and test solutions. Appropriate use of surface texturing and chemical patterning methodologies allow for reduction of both blood coagulation and platelet adhesion, and new methods of surface interrogation at high resolution allow for measurement of the relevant biological factors. PMID:25448722

Enhanced functional recombinant factor VII production by HEK 293 cells stably transfected with VKORC1 where the gamma-carboxylase inhibitor calumenin is stably suppressed by shRNA transfection.

PubMed

Wajih, Nadeem; Owen, John; Wallin, Reidar

2008-01-01

Recombinant members of the vitamin K-dependent protein family (factors IX and VII and protein C) have become important pharmaceuticals in treatment of bleeding disorders and sepsis. However, because the in vivo gamma-carboxylation system in stable cell lines used for transfection has a limited capacity of post translational gamma-carboxylation, the recovery of fully gamma-carboxylated and functional proteins is low. In this work we have engineered recombinant factor VII producing HEK 293 cells to stably overexpress VKORC1, the reduced vitamin K gamma-carboxylase cofactor and in addition stably silenced the gamma-carboxylase inhibitory protein calumenin. Stable cell lines transfected with only a factor VII cDNA had a 9% production of functional recombinant factor VII. On the other hand, these recombinant factor VII producing cells when engineered to overexpress VKORC1 and having calumenin stably suppressed more than 80% by shRNA expression, produced 68% functional factor VII. The technology presented should be applicable to all vertebrae members of the vitamin K-dependent protein family and should lower the production cost of the clinically used factors VII, IX and protein C.

Treatment tailoring for factor V deficient patients and perioperative management using global hemostatic coagulation assays.

PubMed

Levy-Mendelovich, Sarina; Barg, Assaf Arie; Rosenberg, Nurit; Avishai, Einat; Luboshitz, Jacob; Misgav, Mudi; Kenet, Gili; Livnat, Tami

2018-07-01

Congenital factor V deficiency (FVD) is a rare bleeding disorder with an estimated incidence of 1 in 1000,000 in the general population. Since the common coagulation tests do not correlate with the bleeding tendency there is an unmet need to predict FVD patients' bleeding hazard prior to surgical interventions. To optimize treatment prior to surgical interventions, using global coagulation assays, thrombin generation (TG) and rotating thromboelastogram (ROTEM). Our cohort included 5 patients with FVD, 4 severe and one mild. Two of them underwent TG and ROTEM prior to surgical interventions, including ex vivo spiking assays using bypass agents and platelets spiking. All five patients exhibited prolonged PT and PTT, non-dependent on their bleeding tendency. Patient 1, who demonstrated severe bleeding phenotype, underwent surgery treated by combination of APCC (FEIBA) and platelet transfusion. Therapy was guided by global tests (TG as well as ROTEM) results. During the pre and post-operative period neither excessive bleeding nor any thrombosis was noted. In contrast, TG and ROTEM analysis of patient 4 has lead us to perform the surgery without any blood products' support. Indeed, the patient did not encounter any bleeding. Global coagulation assays may be useful ancillary tools guiding treatment decisions in FVD patients undergoing surgical procedures. Copyright © 2018 Elsevier Inc. All rights reserved.

Response surface methodology investigation into the interactions between arsenic and humic acid in water during the coagulation process.

PubMed

Watson, Malcolm Alexander; Tubić, Aleksandra; Agbaba, Jasmina; Nikić, Jasmina; Maletić, Snežana; Molnar Jazić, Jelena; Dalmacija, Božo

2016-07-15

Interactions between arsenic and natural organic matter (NOM) are key limiting factors during the optimisation of drinking water treatment when significant amounts of both must be removed. This work uses Response Surface Methodology (RSM) to investigate how they interact during their simultaneous removal by iron chloride coagulation, using humic acid (HA) as a model NOM substance. Using a three factor Box-Behnken experimental design, As and HA removals were modelled, as well as a combined removal response. ANOVA results showed the significance of the coagulant dose for all three responses. At high initial arsenic concentrations (200μg/l), As removal was significantly hindered by the presence of HA. In contrast, the HA removal response was found to be largely independent of the initial As concentration, with the optimum coagulant dose increasing at increasing HA concentrations. The combined response was similar to the HA removal response, and the interactions evident are most interesting in terms of optimising treatment processes during the preparation of drinking water, highlighting the importance of utilizing RSM for such investigations. The combined response model was successfully validated with two different groundwaters used for drinking water supply in the Republic of Serbia, showing excellent agreement under similar experimental conditions. Copyright © 2016 Elsevier B.V. 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...

Increased circulating procoagulant and anticoagulant factors as TF and TFPI according to severity or infecting serotypes in human dengue infection.

PubMed

Leal de Azeredo, Elzinandes; Solórzano, Victor Edgar Fiestas; de Oliveira, Débora Batista; Marinho, Cintia Ferreira; de Souza, Luiz José; da Cunha, Rivaldo Venâncio; Damasco, Paulo Vieira; Kubelka, Claire Fernandes; de-Oliveira-Pinto, Luzia Maria

2017-01-01

Tissue Factor (TF) is the initiator of coagulation and Tissue Factor Inhibitor (TFPI) is the physiological inhibitor of the TF/FVIIa complex. Circulating levels of TF and TFPI were quantified in dengue patients and the relationships with disease severity and infecting serotype analysed. A significant decrease in TF and TPFI plasma levels was observed in mild DF patients compared with severe dengue. Furthermore, both factors were associated with haemorrhagic manifestations. Finally, TF levels were significantly increased in DENV-1/2 infected patients as compared with DENV-4. These findings suggest that activation of TF-pathway is an important component of DENV -related coagulation disorders. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Identification and Mechanistic Analysis of a Novel Tick-Derived Inhibitor of Thrombin

PubMed Central

Jablonka, Willy; Kotsyfakis, Michalis; Mizurini, Daniella M.; Monteiro, Robson Q.; Lukszo, Jan; Drake, Steven K.; Ribeiro, José M. C.; Andersen, John F.

2015-01-01

A group of peptides from the salivary gland of the tick Hyalomma marginatum rufipes, a vector of Crimean Congo hemorrhagic fever show weak similarity to the madanins, a group of thrombin-inhibitory peptides from a second tick species, Haemaphysalis longicornis. We have evaluated the anti-serine protease activity of one of these H. marginatum peptides that has been given the name hyalomin-1. Hyalomin-1 was found to be a selective inhibitor of thrombin, blocking coagulation of plasma and inhibiting S2238 hydrolysis in a competitive manner with an inhibition constant (Ki) of 12 nM at an ionic strength of 150 mM. It also blocks the thrombin-mediated activation of coagulation factor XI, thrombin-mediated platelet aggregation, and the activation of coagulation factor V by thrombin. Hyalomin-1 is cleaved at a canonical thrombin cleavage site but the cleaved products do not inhibit coagulation. However, the C-terminal cleavage product showed non-competitive inhibition of S2238 hydrolysis. A peptide combining the N-terminal parts of the molecule with the cleavage region did not interact strongly with thrombin, but a 24-residue fragment containing the cleavage region and the C-terminal fragment inhibited the enzyme in a competitive manner and also inhibited coagulation of plasma. These results suggest that the peptide acts by binding to the active site as well as exosite I or the autolysis loop of thrombin. Injection of 2.5 mg/kg of hyalomin-1 increased arterial occlusion time in a mouse model of thrombosis, suggesting this peptide could be a candidate for clinical use as an antithrombotic. PMID:26244557

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\

Code of Federal Regulations, 2010 CFR

1998-10-01

... 45 Public Welfare 1 1998-10-01 1998-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ GENERAL ADMINISTRATION... FINANCIAL ASSISTANCE Procedures [Interim] Interim procedures. Pt. 86, Index Subject Index to Title IX...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\

Code of Federal Regulations, 2010 CFR

1997-10-01

... 45 Public Welfare 1 1997-10-01 1997-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ GENERAL ADMINISTRATION... FINANCIAL ASSISTANCE Procedures [Interim] Interim procedures. Pt. 86, Index Subject Index to Title IX...

The Structure of Carbonic Anhydrase IX Is Adapted for Low-pH Catalysis.

PubMed

Mahon, Brian P; Bhatt, Avni; Socorro, Lilien; Driscoll, Jenna M; Okoh, Cynthia; Lomelino, Carrie L; Mboge, Mam Y; Kurian, Justin J; Tu, Chingkuang; Agbandje-McKenna, Mavis; Frost, Susan C; McKenna, Robert

2016-08-23

Human carbonic anhydrase IX (hCA IX) expression in many cancers is associated with hypoxic tumors and poor patient outcome. Inhibitors of hCA IX have been used as anticancer agents with some entering Phase I clinical trials. hCA IX is transmembrane protein whose catalytic domain faces the extracellular tumor milieu, which is typically associated with an acidic microenvironment. Here, we show that the catalytic domain of hCA IX (hCA IX-c) exhibits the necessary biochemical and biophysical properties that allow for low pH stability and activity. Furthermore, the unfolding process of hCA IX-c appears to be reversible, and its catalytic efficiency is thought to be correlated directly with its stability between pH 3.0 and 8.0 but not above pH 8.0. To rationalize this, we determined the X-ray crystal structure of hCA IX-c to 1.6 Å resolution. Insights from this study suggest an understanding of hCA IX-c stability and activity in low-pH tumor microenvironments and may be applicable to determining pH-related effects on enzymes.

[Haplotype Analysis of Coagulation Factor VII Gene in a Patient with Congenital Coagulation Factor VII Deficiency with Heterozygous p.Arg337Cys Mutation and o.Aro413Gin Polymorphism..

PubMed

Suzuki, Keijiro; Yoshioka, Tomoko; Obara, Takehiro; Suwabe, Akira

2016-05-01

Congenital coagulation factor VII (FVII) deficiency is a rare hemorrhagic disease with an autosomal reces- sive inheritance pattern. We analyzed coagulation factor VII gene (F7) of a patient with FVII deficiency and used expression studies to investigate the effect of a missense mutation on FVII secretion. The proband, a 69-year-old Japanese woman, had a history of postpartum bleeding and excessive bleeding after dental extrac- tion. She was found to have mildly increased PT-INR (1.17) before an ophthalmic operation. FVII activity and antigen were reduced (29.0% and 32.8%). Suspecting that the proband was FVII deficient, we analyzed F7 of the patient. Sequence analysis revealed that the patient was heterozygous for a point mutation (p.Arg337Cys) in the catalytic domain and polymorphisms: the decanucleotide insertion at the promoter re- gion, dimorphism (c.525C >T) in exon 5, and p.Arg413Gln in exon 8. Haplotype analysis clarified that p.Arg337Cys was located on the p.Arg413 allele (Ml allele). The other allele had the p.Arg413Gln polymor- phism(M2 allele) which is known to produce less FVII. Expression studies revealed that p.Arg337Cys causes impairment of FVII secretion. Insufficient secretion of FVII arising from both the p.Arg337Cys/M1 allele and the p.Arg337/M2 allele might lower the FVII level of this patient(<50%). The FVII level in a heterozygous FVII deficient patient might be influenced by F7 polymorphisms on the normal allele. There- fore, genetic analyses are important for the diagnosis of heterozygous FVII deficiency.

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

21 CFR 864.7290 - Factor deficiency test.

Code of Federal Regulations, 2010 CFR

2010-04-01

... state (a person carrying both a recessive gene for a coagulation factor deficiency such as hemophilia and the corresponding normal gene). (b) Classification. Class II (performance standards). [45 FR 60613...

Losac, the First Hemolin that Exhibits Procogulant Activity through Selective Factor X Proteolytic Activation*

PubMed Central

Alvarez-Flores, Miryam Paola; Furlin, Daniel; Ramos, Oscar H. P.; Balan, Andrea; Konno, Katsuhiro; Chudzinski-Tavassi, Ana Marisa

2011-01-01

Envenoming by the contact of human skin with Lonomia obliqua caterpillars promotes a hemorrhagic syndrome characterized by a consumptive coagulopathy. Losac (Lonomia obliqua Stuart factor activator) is a component of the bristle of L. obliqua that is probably partially responsible for the observed syndrome because it activates factor X and is recognized by an effective antilonomic serum. Here we unveil the proteolytic activity of Losac and demonstrate the feasibility of its recombinant production. On the other hand, Losac has no homology to known proteases, but it can be inhibited by PMSF, a serine protease inhibitor. Instead, it shows closer homology to members of the hemolin family of proteins, a group of cell adhesion molecules. The recombinant protein (rLosac) shortened the coagulation time of normal and deficient plasmas, whereas it was ineffective in factor X-deficient plasma unless reconstituted with this protein. rLosac was able to activate factor X in a dose- and time-dependent manner but not γ-carboxyglutamic acid domainless factor X. Moreover, phospholipids and calcium ions increased rLosac activity. Also, rLosac had no effect on fibrin or fibrinogen, indicating its specificity for blood coagulation activation. Linear double reciprocal plots indicate that rLosac follows a Michaelis-Menten kinetics. Cleavage of factor X by rLosac resulted in fragments that are compatible with those generated by RVV-X (a well known factor X activator). Together, our results validate Losac as the first protein from the hemolin family exhibiting procoagulant activity through selective proteolysis on coagulation factor X. PMID:21177860

Confinement Regulates Complex Biochemical Networks: Initiation of Blood Clotting by “Diffusion Acting”

PubMed Central

Shen, Feng; Pompano, Rebecca R.; Kastrup, Christian J.; Ismagilov, Rustem F.

2009-01-01

Abstract 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, Da2, 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. PMID:19843446

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.

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.

Tissue factor expression by endothelial cells in sickle cell anemia.

PubMed

Solovey, A; Gui, L; Key, N S; Hebbel, R P

1998-05-01

The role of the vascular endothelium in activation of the coagulation system, a fundamental homeostatic mechanism of mammalian biology, is uncertain because there is little evidence indicating that endothelial cells in vivo express tissue factor (TF), the system's triggering mechanism. As a surrogate for vessel wall endothelium, we examined circulating endothelial cells (CEC) from normals and patients with sickle cell anemia, a disease associated with activation of coagulation. We find that sickle CEC abnormally express TF antigen (expressed as percent CEC that are TF-positive), with 66+/-13% positive in sickle patients in steady-state, 83+/-19% positive in sickle patients presenting with acute vasoocclusive episodes, and only 10+/-13% positive in normal controls. Repeated samplings confirmed this impression that TF expression is greater when sickle patients develop acute vasoocclusive episodes. Sickle CEC are also positive for TF mRNA, with excellent concurrence between antigen and mRNA expression. The TF expressed on the antigen-positive CEC is functional, as demonstrated by a binding assay for Factor VIIa and a chromogenic assay sensitive to generation of Factor Xa. By establishing that endothelial cells in vivo can express TF, these data imply that the vast endothelial surface area does provide an important pathophysiologic trigger for coagulation activation.

Amorphous nanosilicas induce consumptive coagulopathy after systemic exposure

NASA Astrophysics Data System (ADS)

Nabeshi, Hiromi; Yoshikawa, Tomoaki; Matsuyama, Keigo; Nakazato, Yasutaro; Arimori, Akihiro; Isobe, Masaaki; Tochigi, Saeko; Kondoh, Sayuri; Hirai, Toshiro; Akase, Takanori; Yamashita, Takuya; Yamashita, Kohei; Yoshida, Tokuyuki; Nagano, Kazuya; Abe, Yasuhiro; Yoshioka, Yasuo; Kamada, Haruhiko; Imazawa, Takayoshi; Itoh, Norio; Kondoh, Masuo; Yagi, Kiyohito; Mayumi, Tadanori; Tsunoda, Shin-ichi; Tsutsumi, Yasuo

2012-02-01

We previously reported that well-dispersed amorphous nanosilicas with particle size 70 nm (nSP70) penetrate skin and produce systemic exposure after topical application. These findings underscore the need to examine biological effects after systemic exposure to nanosilicas. The present study was designed to examine the biological effects. BALB/c mice were intravenously injected with amorphous nanosilicas of sizes 70, 100, 300, 1000 nm and then assessed for survival, blood biochemistry, and coagulation. As a result, injection of nSP70 caused fatal toxicity, liver damage, and platelet depletion, suggesting that nSP70 caused consumptive coagulopathy. Additionally, nSP70 exerts procoagulant activity in vitro associated with an increase in specific surface area, which increases as diameter reduces. In contrast, nSP70-mediated procoagulant activity was absent in factor XII-deficient plasma. Collectively, we revealed that interaction between nSP70 and intrinsic coagulation factors such as factor XII, were deeply related to nSP70-induced harmful effects. In other words, it is suggested that if interaction between nSP70 and coagulation factors can be suppressed, nSP70-induced harmful effects may be avoided. These results would provide useful information for ensuring the safety of nanomaterials (NMs) and open new frontiers in biological fields by the use of NMs.

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\

Code of Federal Regulations, 2010 CFR

2000-10-01

... 45 Public Welfare 1 2000-10-01 2000-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ Public Welfare DEPARTMENT OF... procedures. Pt. 86, Index Subject Index to Title IX Preamble and Regulation \\1\\ 1 Preamble paragraph numbers...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2002-10-01

... 45 Public Welfare 1 2002-10-01 2002-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare GENERAL ADMINISTRATION... FINANCIAL ASSISTANCE Procedures [Interim] Interim procedures. Pt. 86, Index Subject Index to Title IX...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\

Code of Federal Regulations, 2010 CFR

1999-10-01

... 45 Public Welfare 1 1999-10-01 1999-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ Public Welfare DEPARTMENT OF... procedures. Pt. 86, Index Subject Index to Title IX Preamble and Regulation \\1\\ 1 Preamble paragraph numbers...

Edible bird’s nest attenuates procoagulation effects of high-fat diet in rats

PubMed Central

Yida, Zhang; Imam, Mustapha Umar; Ismail, Maznah; Ismail, Norsharina; Hou, Zhiping

2015-01-01

Edible bird’s nest (EBN) is popular in Asia, and has long been used traditionally as a supplement. There are, however, limited evidence-based studies on its efficacy. EBN has been reported to improve dyslipidemia, which is closely linked to hypercoagulation states. In the present study, the effects of EBN on high-fat diet- (HFD-) induced coagulation in rats were evaluated. Rats were fed for 12 weeks with HFD alone or in combination with simvastatin or EBN. Food intake was estimated, and weight measurements were made during the experimental period. After sacrifice, serum oxidized low-density lipoprotein (oxLDL), adiponectin, leptin, von willibrand factor, prostacyclin, thromboxane and lipid profile, and whole blood coagulation indices (bleeding time, prothrombin time, activated partial thromboplastin time, red blood count count, and platelet count) were estimated. Furthermore, hepatic expression of coagulation-related genes was evaluated using multiplex polymerase chain reaction. The results indicated that EBN could attenuate HFD-induced hypercholesterolemia and coagulation similar to simvastatin, partly through transcriptional regulation of coagulation-related genes. The results suggested that EBN has the potential for lowering the risk of cardiovascular disease-related hypercoagulation due to hypercholesterolemia. PMID:26251574

Complement component 5 promotes lethal thrombosis

PubMed Central

Mizuno, Tomohiro; Yoshioka, Kengo; Mizuno, Masashi; Shimizu, Mie; Nagano, Fumihiko; Okuda, Tomoyuki; Tsuboi, Naotake; Maruyama, Shoichi; Nagamatsu, Tadashi; Imai, Masaki

2017-01-01

Extracellular histones promote platelet aggregation and thrombosis; this is followed by induction of coagulation disorder, which results in exhaustion of coagulation factors. Complement component 5 (C5) is known to be associated with platelet aggregation and coagulation system activation. To date, the pathological mechanism underlying liver injury has remained unclear. Here, we investigated whether C5 promotes liver injury associated with histone-induced lethal thrombosis. C5-sufficient and C5-deficient mice received single tail vein injections of purified, unfractionated histones obtained from calf thymus (45–75 μg/g). Subsequently, the mice were monitored for survival for up to 72 h. Based on the survival data, the 45 μg/g dose was used for analysis of blood cell count, liver function, blood coagulation ability, and promotion of platelet aggregation and platelet/leukocyte aggregate (PLA) production by extracellular histones. C5-deficient mice were protected from lethal thrombosis and had milder thrombocytopenia, consumptive coagulopathy, and liver injury with embolism and lower PLA production than C5-sufficient mice. These results indicate that C5 is associated with coagulation disorders, PLA production, and embolism-induced liver injury. In conclusion, C5 promotes liver injury associated with histone-induced lethal thrombosis. PMID:28205538

Host defense peptides of thrombin modulate inflammation and coagulation in endotoxin-mediated shock and Pseudomonas aeruginosa sepsis.

PubMed

Kalle, Martina; Papareddy, Praveen; Kasetty, Gopinath; Mörgelin, Matthias; van der Plas, Mariena J A; Rydengård, Victoria; Malmsten, Martin; Albiger, Barbara; Schmidtchen, Artur

2012-01-01

Gram-negative sepsis is accompanied by a disproportionate innate immune response and excessive coagulation mainly induced by endotoxins released from bacteria. Due to rising antibiotic resistance and current lack of other effective treatments there is an urgent need for new therapies. We here present a new treatment concept for sepsis and endotoxin-mediated shock, based on host defense peptides from the C-terminal part of human thrombin, found to have a broad and inhibitory effect on multiple sepsis pathologies. Thus, the peptides abrogate pro-inflammatory cytokine responses to endotoxin in vitro and in vivo. Furthermore, they interfere with coagulation by modulating contact activation and tissue factor-mediated clotting in vitro, leading to normalization of coagulation responses in vivo, a previously unknown function of host defense peptides. In a mouse model of Pseudomonas aeruginosa sepsis, the peptide GKY25, while mediating a modest antimicrobial effect, significantly inhibited the pro-inflammatory response, decreased fibrin deposition and leakage in the lungs, as well as reduced mortality. Taken together, the capacity of such thrombin-derived peptides to simultaneously modulate bacterial levels, pro-inflammatory responses, and coagulation, renders them attractive therapeutic candidates for the treatment of invasive infections and sepsis.

Inhibition of carbonic anhydrase isoforms I, II, IX and XII with novel Schiff bases: identification of selective inhibitors for the tumor-associated isoforms over the cytosolic ones.

PubMed

Sarikaya, Busra; Ceruso, Mariangela; Carta, Fabrizio; Supuran, Claudiu T

2014-11-01

A series of new Schiff bases was obtained from sulfanilamide, 3-fluorosulfanilamide or 4-(2-aminoethyl)-benzenesulfonamide and aromatic/heterocyclic aldehydes incorporating both hydrophobic and hydrophilic moieties. The obtained sulfonamides were investigated as inhibitors of four physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isoforms, the cytosolic CA I and II, as well as the transmembrane, tumor-associated CA IX and XII. Most derivatives were medium potency or weak hCA I/II inhibitors, but several of them showed nanomolar affinity for CA IX and/or XII, making them an interesting example of isoform-selective compounds. The nature of the aryl/hetaryl moiety present in the initial aldehyde was the main factor influencing potency and isoform selectivity. The best and most CA IX-selective compounds incorporated moieties such as 4-methylthiophenyl, 4-cyanophenyl-, 4-(2-pyridyl)-phenyl and the 4-aminoethylbenzenesulfonamide scaffold. The best hCA XII inhibitors, also showing selectivity for this isoform, incorporated 2-methoxy-4-nitrophenyl-, 2,3,5,6-tetrafluorophenyl and 4-(2-pyridyl)-phenyl functionalities and were also derivatives of 4-aminoethylbenzenesulfonamide. The sulfanilamide and 3-fluorosulfanilamide derived Schiff bases were less active compared to the corresponding 4-aminoethyl-benzenesulfonamide derivatives. As hCA IX/XII selective inhibition is attractive for obtaining antitumor agents/diagnostic tools with a new mechanism of action, compounds of the type described here may be considered interesting preclinical candidates. Copyright © 2014 Elsevier Ltd. All rights reserved.

Surface roughness of glass ionomer cements indicated for uncooperative patients according to surface protection treatment

PubMed Central

Pacifici, Edoardo; Bossù, Maurizio; Giovannetti, Agostino; La Torre, Giuseppe; Guerra, Fabrizio; Polimeni, Antonella

2013-01-01

Summary Background Even today, use of Glass Ionomer Cements (GIC) as restorative material is indicated for uncooperative patients. Aim The study aimed at estimating the surface roughness of different GICs using or not their proprietary surface coatings and at observing the interfaces between cement and coating through SEM. Materials and methods Forty specimens have been obtained and divided into 4 groups: Fuji IX (IX), Fuji IX/G-Coat Plus (IXC), Vitremer (V), Vitremer/Finishing Gloss (VFG). Samples were obtained using silicone moulds to simulate class I restorations. All specimens were processed for profilometric evaluation. The statistical differences of surface roughness between groups were assessed using One-Way Analysis of Variance (One-Way ANOVA) (p<0.05). The Two-Way Analysis of Variance (Two-Way ANOVA) was used to evaluate the influence of two factors: restoration material and presence of coating. Coated restoration specimens (IXC and VFG) were sectioned perpendicular to the restoration surface and processed for SEM evaluation. Results No statistical differences in roughness could be noticed between groups or factors. Following microscopic observation, interfaces between restoration material and coating were better for group IXC than for group VFG. Conclusions When specimens are obtained simulating normal clinical procedures, the presence of surface protection does not significantly improve the surface roughness of GICs. PMID:24611090

Surface roughness of glass ionomer cements indicated for uncooperative patients according to surface protection treatment.

PubMed

Pacifici, Edoardo; Bossù, Maurizio; Giovannetti, Agostino; La Torre, Giuseppe; Guerra, Fabrizio; Polimeni, Antonella

2013-01-01

Even today, use of Glass Ionomer Cements (GIC) as restorative material is indicated for uncooperative patients. The study aimed at estimating the surface roughness of different GICs using or not their proprietary surface coatings and at observing the interfaces between cement and coating through SEM. Forty specimens have been obtained and divided into 4 groups: Fuji IX (IX), Fuji IX/G-Coat Plus (IXC), Vitremer (V), Vitremer/Finishing Gloss (VFG). Samples were obtained using silicone moulds to simulate class I restorations. All specimens were processed for profilometric evaluation. The statistical differences of surface roughness between groups were assessed using One-Way Analysis of Variance (One-Way ANOVA) (p<0.05). The Two-Way Analysis of Variance (Two-Way ANOVA) was used to evaluate the influence of two factors: restoration material and presence of coating. Coated restoration specimens (IXC and VFG) were sectioned perpendicular to the restoration surface and processed for SEM evaluation. No statistical differences in roughness could be noticed between groups or factors. Following microscopic observation, interfaces between restoration material and coating were better for group IXC than for group VFG. When specimens are obtained simulating normal clinical procedures, the presence of surface protection does not significantly improve the surface roughness of GICs.

Comparative proteomic analysis of normal and collagen IX null mouse cartilage reveals altered extracellular matrix composition and novel components of the collagen IX interactome.

PubMed

Brachvogel, Bent; Zaucke, Frank; Dave, Keyur; Norris, Emma L; Stermann, Jacek; Dayakli, Münire; Koch, Manuel; Gorman, Jeffrey J; Bateman, John F; Wilson, Richard

2013-05-10

Collagen IX is an integral cartilage extracellular matrix component important in skeletal development and joint function. Proteomic analysis and validation studies revealed novel alterations in collagen IX null cartilage. Matrilin-4, collagen XII, thrombospondin-4, fibronectin, βig-h3, and epiphycan are components of the in vivo collagen IX interactome. We applied a proteomics approach to advance our understanding of collagen IX ablation in cartilage. The cartilage extracellular matrix is essential for endochondral bone development and joint function. In addition to the major aggrecan/collagen II framework, the interacting complex of collagen IX, matrilin-3, and cartilage oligomeric matrix protein (COMP) is essential for cartilage matrix stability, as mutations in Col9a1, Col9a2, Col9a3, Comp, and Matn3 genes cause multiple epiphyseal dysplasia, in which patients develop early onset osteoarthritis. In mice, collagen IX ablation results in severely disturbed growth plate organization, hypocellular regions, and abnormal chondrocyte shape. This abnormal differentiation is likely to involve altered cell-matrix interactions but the mechanism is not known. To investigate the molecular basis of the collagen IX null phenotype we analyzed global differences in protein abundance between wild-type and knock-out femoral head cartilage by capillary HPLC tandem mass spectrometry. We identified 297 proteins in 3-day cartilage and 397 proteins in 21-day cartilage. Components that were differentially abundant between wild-type and collagen IX-deficient cartilage included 15 extracellular matrix proteins. Collagen IX ablation was associated with dramatically reduced COMP and matrilin-3, consistent with known interactions. Matrilin-1, matrilin-4, epiphycan, and thrombospondin-4 levels were reduced in collagen IX null cartilage, providing the first in vivo evidence for these proteins belonging to the collagen IX interactome. Thrombospondin-4 expression was reduced at the mRNA level, whereas matrilin-4 was verified as a novel collagen IX-binding protein. Furthermore, changes in TGFβ-induced protein βig-h3 and fibronectin abundance were found in the collagen IX knock-out but not associated with COMP ablation, indicating specific involvement in the abnormal collagen IX null cartilage. In addition, the more widespread expression of collagen XII in the collagen IX-deficient cartilage suggests an attempted compensatory response to the absence of collagen IX. Our differential proteomic analysis of cartilage is a novel approach to identify candidate matrix protein interactions in vivo, underpinning further analysis of mutant cartilage lacking other matrix components or harboring disease-causing mutations.

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

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay

PubMed Central

Tilley, Derek; Levit, Irina; Samis, John A.

2012-01-01

In response to injury, blood coagulation is activated and results in generation of the clotting protease, thrombin. Thrombin cleaves fibrinogen to fibrin which forms an insoluble clot that stops hemorrhage. Factor V (FV) in its activated form, FVa, is a critical cofactor for the protease FXa and accelerator of thrombin generation during fibrin clot formation as part of prothrombinase 1, 2. Manual FV assays have been described 3, 4, but they are time consuming and subjective. Automated FV assays have been reported 5-7, but the analyzer and reagents are expensive and generally provide only the clot time, not the rate and extent of fibrin formation. The microplate platform is preferred for measuring enzyme-catalyzed events because of convenience, time, cost, small volume, continuous monitoring, and high-throughput 8, 9. Microplate assays have been reported for clot lysis 10, platelet aggregation 11, and coagulation Factors 12, but not for FV activity in human plasma. The goal of the method was to develop a microplate assay that measures FV activity during fibrin formation in human plasma. This novel microplate method outlines a simple, inexpensive, and rapid assay of FV activity in human plasma. The assay utilizes a kinetic microplate reader to monitor the absorbance change at 405nm during fibrin formation in human plasma (Figure 1) 13. The assay accurately measures the time, initial rate, and extent of fibrin clot formation. It requires only μl quantities of plasma, is complete in 6 min, has high-throughput, is sensitive to 24-80pM FV, and measures the amount of unintentionally activated (1-stage activity) and thrombin-activated FV (2-stage activity) to obtain a complete assessment of its total functional activity (2-stage activity - 1-stage activity). Disseminated intravascular coagulation (DIC) is an acquired coagulopathy that most often develops from pre-existing infections 14. DIC is associated with a poor prognosis and increases mortality above the pre-existing pathology 15. The assay was used to show that in 9 patients with DIC, the FV 1-stage, 2-stage, and total activities were decreased, on average, by 54%, 44%, and 42%, respectively, compared with normal pooled human reference plasma (NHP). The FV microplate assay is easily adaptable to measure the activity of any coagulation factor. This assay will increase our understanding of FV biochemistry through a more accurate and complete measurement of its activity in research and clinical settings. This information will positively impact healthcare environments through earlier diagnosis and development of more effective treatments for coagulation disorders, such as DIC. PMID:22987015

Measurement of factor v activity in human plasma using a microplate coagulation assay.

PubMed

Tilley, Derek; Levit, Irina; Samis, John A

2012-09-09

In response to injury, blood coagulation is activated and results in generation of the clotting protease, thrombin. Thrombin cleaves fibrinogen to fibrin which forms an insoluble clot that stops hemorrhage. Factor V (FV) in its activated form, FVa, is a critical cofactor for the protease FXa and accelerator of thrombin generation during fibrin clot formation as part of prothrombinase (1, 2). Manual FV assays have been described (3, 4), but they are time consuming and subjective. Automated FV assays have been reported (5-7), but the analyzer and reagents are expensive and generally provide only the clot time, not the rate and extent of fibrin formation. The microplate platform is preferred for measuring enzyme-catalyzed events because of convenience, time, cost, small volume, continuous monitoring, and high-throughput (8, 9). Microplate assays have been reported for clot lysis (10), platelet aggregation (11), and coagulation Factors (12), but not for FV activity in human plasma. The goal of the method was to develop a microplate assay that measures FV activity during fibrin formation in human plasma. This novel microplate method outlines a simple, inexpensive, and rapid assay of FV activity in human plasma. The assay utilizes a kinetic microplate reader to monitor the absorbance change at 405 nm during fibrin formation in human plasma (Figure 1) (13). The assay accurately measures the time, initial rate, and extent of fibrin clot formation. It requires only μl quantities of plasma, is complete in 6 min, has high-throughput, is sensitive to 24-80 pM FV, and measures the amount of unintentionally activated (1-stage activity) and thrombin-activated FV (2-stage activity) to obtain a complete assessment of its total functional activity (2-stage activity - 1-stage activity). Disseminated intravascular coagulation (DIC) is an acquired coagulopathy that most often develops from pre-existing infections (14). DIC is associated with a poor prognosis and increases mortality above the pre-existing pathology (15). The assay was used to show that in 9 patients with DIC, the FV 1-stage, 2-stage, and total activities were decreased, on average, by 54%, 44%, and 42%, respectively, compared with normal pooled human reference plasma (NHP). The FV microplate assay is easily adaptable to measure the activity of any coagulation factor. This assay will increase our understanding of FV biochemistry through a more accurate and complete measurement of its activity in research and clinical settings. This information will positively impact healthcare environments through earlier diagnosis and development of more effective treatments for coagulation disorders, such as DIC.

Analysis of the N-glycans of recombinant human Factor IX purified from transgenic pig milk

PubMed Central

Gil, Geun-Cheol; Velander, William H; Van Cott, Kevin E

2008-01-01

Glycosylation of recombinant proteins is of particular importance because it can play significant roles in the clinical properties of the glycoprotein. In this work, the N-glycan structures of recombinant human Factor IX (tg-FIX) produced in the transgenic pig mammary gland were determined. The majority of the N-glycans of transgenic pig-derived Factor IX (tg-FIX) are complex, bi-antennary with one or two terminal N-acetylneuraminic acid (Neu5Ac) moieties. We also found that the N-glycan structures of tg-FIX produced in the porcine mammary epithelial cells differed with respect to N-glycans from glycoproteins produced in other porcine tissues. tg-FIX contains no detectable Neu5Gc, the sialic acid commonly found in porcine glycoproteins produced in other tissues. Additionally, we were unable to detect glycans in tg-FIX that have a terminal Galα(1,3)Gal disaccharide sequence, which is strongly antigenic in humans. The N-glycan structures of tg-FIX are also compared to the published N-glycan structures of recombinant human glycoproteins produced in other transgenic animal species. While tg-FIX contains only complex structures, antithrombin III (goat), C1 inhibitor (rabbit), and lactoferrin (cow) have both high mannose and complex structures. Collectively, these data represent a beginning point for the future investigation of species-specific and tissue/cell-specific differences in N-glycan structures among animals used for transgenic animal bioreactors. PMID:18456721

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2011 CFR

2011-07-01

... 34 Education 1 2011-07-01 2011-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2011 CFR

2011-10-01

... 45 Public Welfare 1 2011-10-01 2011-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTH AND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTH AND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2003-10-01

... 45 Public Welfare 1 2003-10-01 2003-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND.... Pt. 86, Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2009-07-01

... 34 Education 1 2009-07-01 2009-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

34 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2015-07-01

... 34 Education 1 2015-07-01 2015-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2003-07-01

... 34 Education 1 2003-07-01 2003-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2006-10-01

... 45 Public Welfare 1 2006-10-01 2006-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

34 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2016-07-01

... 34 Education 1 2016-07-01 2016-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2007-07-01

... 34 Education 1 2007-07-01 2007-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2004-07-01

... 34 Education 1 2004-07-01 2004-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2016-10-01

... 45 Public Welfare 1 2016-10-01 2016-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare Department of Health and... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2012-07-01

... 34 Education 1 2012-07-01 2012-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2017-10-01

... 45 Public Welfare 1 2017-10-01 2017-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare Department of Health and... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2008-07-01

... 34 Education 1 2008-07-01 2008-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2013-10-01

... 45 Public Welfare 1 2013-10-01 2013-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTH AND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2009-10-01

... 45 Public Welfare 1 2009-10-01 2009-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTH AND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2004-10-01

... 45 Public Welfare 1 2004-10-01 2004-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND.... Pt. 86, Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2014-10-01

... 45 Public Welfare 1 2014-10-01 2014-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare Department of Health and... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2012-10-01

... 45 Public Welfare 1 2012-10-01 2012-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTH AND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2005-10-01

... 45 Public Welfare 1 2005-10-01 2005-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTH AND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2007-10-01

... 45 Public Welfare 1 2007-10-01 2007-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2006-07-01

... 34 Education 1 2006-07-01 2006-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2002-07-01

... 34 Education 1 2002-07-01 2002-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Regulations of the Offices of the Department...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2014-07-01

... 34 Education 1 2014-07-01 2014-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2005-07-01

... 34 Education 1 2005-07-01 2005-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2001-10-01

... 45 Public Welfare 1 2001-10-01 2001-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND.... Pt. 86, Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2008-10-01

... 45 Public Welfare 1 2008-10-01 2008-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare DEPARTMENT OF HEALTHAND... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

34 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2013-07-01

... 34 Education 1 2013-07-01 2013-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

45 CFR Subject Index to Title Ix... - Subject Index to Title IX Preamble and Regulation \\1\\

Code of Federal Regulations, 2010 CFR

1996-10-01

... 45 Public Welfare 1 1996-10-01 1996-10-01 false Subject Index to Title IX Preamble and Regulation \\1\\ Index Subject Index to Title IX Preamble and Regulation \\1\\ NONDISCRIMINATION ON THE BASIS OF SEX... Procedures [Interim] Interim procedures. Pt. 86, Index Subject Index to Title IX Preamble and Regulation \\1...

45 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2015-10-01

... 45 Public Welfare 1 2015-10-01 2015-10-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Public Welfare Department of Health and... Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers are in brackets [ ]. A...

34 CFR Subject Index to Title IX... - Subject Index to Title IX Preamble and Regulation 1

Code of Federal Regulations, 2010 CFR

2017-07-01

... 34 Education 1 2017-07-01 2017-07-01 false Subject Index to Title IX Preamble and Regulation 1 Index Subject Index to Title IX Preamble and Regulation 1 Education Regulations of the Offices of the...] Procedures. Subject Index Subject Index to Title IX Preamble and Regulation 1 1 Preamble paragraph numbers...

Purification and Autoactivation Method for Recombinant Coagulation Factor VII.

PubMed

Granovski, Vladimir; Freitas, Marcela C C; Abreu-Neto, Mario Soares; Covas, Dimas T

2018-01-01

Recombinant coagulation factor VII is a very important and complex protein employed for treatment of hemophiliac patients (hemophilia A/B) who develop inhibitors antibodies to conventional treatments (FVIII and FIX). The rFVII is a glycosylated molecule and circulates in plasma as zymogen of 50 kDa. When activated the molecule is cleaved to 20-30 kDa and has a half-life of about 3 h, needing to be processed fast and efficiently until freeze-drying. Here, we describe a very simple and fast purification sequence for rFVII using affinity FVII Select resin and a dialysis system that can be easily scaled up.

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.

A Comparison of Blood Factor XII Autoactivation in Buffer, Protein Cocktail, Serum, and Plasma Solutions

PubMed Central

Golas, Avantika; Yeh, Chyi-Huey Josh; Pitakjakpipop, Harit; Siedlecki, Christopher A.; Vogler, Erwin A.

2012-01-01

Activation of blood plasma coagulation in vitro by contact with material surfaces is demonstrably dependent on plasma-volume-to-activator-surface-area ratio. The only plausible explanation consistent with current understanding of coagulation-cascade biochemistry is that procoagulant stimulus arising from the activation complex of the intrinsic pathway is dependent on activator surface area. And yet, it is herein shown that activation of the blood zymogen factor XII (Hageman factor, FXII) dissolved in buffer, protein cocktail, heat-denatured serum, and FXI deficient plasma does not exhibit activator surface-area dependence. Instead, a highly-variable burst of procoagulant-enzyme yield is measured that exhibits no measurable kinetics, sensitivity to mixing, or solution-temperature dependence. Thus, FXII activation in both buffer and protein-containing solutions does not exhibit characteristics of a biochemical reaction but rather appears to be a “mechanochemical” reaction induced by FXII molecule interactions with hydrophilic activator particles that do not formally adsorb blood proteins from solution. Results of this study strongly suggest that activator surface-area dependence observed in contact activation of plasma coagulation does not solely arise at the FXII activation step of the intrinsic pathway. PMID:23117212

Thermoelectric properties of Tl and I dual-doped Bi2Te3-based alloys

NASA Astrophysics Data System (ADS)

Wu, Fang; He, Qinglin; Tang, Mingsheng; Song, Hongzhang

2018-04-01

TlxBi2‑xTe3‑xIx (x = 0, 0.05, 0.1 and 0.2) flower-like nanopowders were prepared successfully by the hydrothermal method. Then, the synthesized nanoparticles were pressed into bulks by hot-pressing. The thermoelectric (TE) properties of the TlxBi2‑xTe3‑xIx bulk samples were investigated and discussed. The results showed that the influences of Tl doping on the electrical resistivity and Seebeck coefficients of the Bi2Te3 is over that of I doping. Thus, the power factors of the dual-doped bulks are all less than that of the Bi2Te3 bulk. The thermal conductivities of the TlxBi2‑xTe3‑xIx bulk samples also remain at lower values. As a result, the ZT value of the optimized doped bulk Tl0.1Bi1.9Te2.9I0.1 attains a value of 1.1 at 398 K.

Genetic modification of bone-marrow mesenchymal stem cells and hematopoietic cells with human coagulation factor IX-expressing plasmids.

PubMed

Sam, Mohammad Reza; Azadbakhsh, Azadeh Sadat; Farokhi, Farrah; Rezazadeh, Kobra; Sam, Sohrab; Zomorodipour, Alireza; Haddad-Mashadrizeh, Aliakbar; Delirezh, Nowruz; Mokarizadeh, Aram

2016-05-01

Ex-vivo gene therapy of hemophilias requires suitable bioreactors for secretion of hFIX into the circulation and stem cells hold great potentials in this regard. Viral vectors are widely manipulated and used to transfer hFIX gene into stem cells. However, little attention has been paid to the manipulation of hFIX transgene itself. Concurrently, the efficacy of such a therapeutic approach depends on determination of which vectors give maximal transgene expression. With this in mind, TF-1 (primary hematopoietic lineage) and rat-bone marrow mesenchymal stem cells (BMSCs) were transfected with five hFIX-expressing plasmids containing different combinations of two human β-globin (hBG) introns inside the hFIX-cDNA and Kozak element and hFIX expression was evaluated by different methods. In BMSCs and TF-1 cells, the highest hFIX level was obtained from the intron-less and hBG intron-I,II containing plasmids respectively. The highest hFIX activity was obtained from the cells that carrying the hBG intron-I,II containing plasmids. BMSCs were able to produce higher hFIX by 1.4 to 4.7-fold increase with activity by 2.4 to 4.4-fold increase compared to TF-1 cells transfected with the same constructs. BMSCs and TF-1 cells could be effectively bioengineered without the use of viral vectors and hFIX minigene containing hBG introns could represent a particular interest in stem cell-based gene therapy of hemophilias. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

A direct comparison of two nonviral gene therapy vectors for somatic integration: in vivo evaluation of the bacteriophage integrase phiC31 and the Sleeping Beauty transposase.

PubMed

Ehrhardt, Anja; Xu, Hui; Huang, Zan; Engler, Jeffrey A; Kay, Mark A

2005-05-01

In this study we performed a head-to-head comparison of the integrase phiC31 derived from a Streptomyces phage and the Sleeping Beauty (SB) transposase, a member of the TC1/mariner superfamily of transposable elements. Mouse liver was cotransfused with a vector containing our most robust human coagulation factor IX expression cassette and the appropriate recombinase recognition site and either a phiC31- or a SB transposase-expressing vector. To analyze transgene persistence and to prove somatic integration in vivo we induced cell cycling of mouse hepatocytes and found that the transgene expression levels dropped by only 16 to 21% and 56 to 66% in mice that received phiC31 and SB, respectively. Notably, no difference in the toxicity profile was detected in mice treated with either recombinase. Moreover we observed that with the integrase-mediated gene transfer, transgene expression levels were dependent on the remaining noncoding vector sequences, which also integrate into the host genome. Further analyses of a hot spot of integration after phiC31-mediated integration revealed small chromosomal deletions at the target site and that the recombination process was not dependent on the orientation in which the phiC31 recognition site attached to the pseudo-recognition sites in the host genome. Coupled together with ongoing improvements in both systems this study suggests that both nonviral vector systems will have important roles in achieving stable gene transfer in vivo.

Recombinant epidermal growth factor-like domain-1 from coagulation factor VII functionalized iron oxide nanoparticles for targeted glioma magnetic resonance imaging.

PubMed

Liu, Heng; Chen, Xiao; Xue, Wei; Chu, Chengchao; Liu, Yu; Tong, Haipeng; Du, Xuesong; Xie, Tian; Liu, Gang; Zhang, Weiguo

The highly infiltrative and invasive nature of glioma cells often leads to blurred tumor margins, resulting in incomplete tumor resection and tumor recurrence. Accurate detection and precise delineation of glioma help in preoperative delineation, surgical planning and survival prediction. In this study, recombinant epidermal growth factor-like domain-1, derived from human coagulation factor VII, was conjugated to iron oxide nanoparticles (IONPs) for targeted glioma magnetic resonance (MR) imaging. The synthesized EGF1-EGFP-IONPs exhibited excellent targeting ability toward tissue factor (TF)-positive U87MG cells and human umbilical vein endothelial cells in vitro, and demonstrated persistent and efficient MR contrast enhancement up to 12 h for preclinical glioma models with high targeting specificity in vivo. They hold great potential for clinical translation and developing targeted theranostics against brain glioma.

The effect of a nano-filled resin coating on the 3-year clinical performance of a conventional high-viscosity glass-ionomer cement.

PubMed

Diem, Vu Thi Kieu; Tyas, Martin J; Ngo, Hien C; Phuong, Lam Hoai; Khanh, Ngo Dong

2014-04-01

The main aim of the study was to compare the clinical performance of the conventional high-powder/liquid ratio glass-ionomer cement (GIC) Fuji IX GP Extra (F IX), Fuji IX GP Extra with a low-viscosity nano-filled resin coating, G-Coat Plus (F IX+GCP), and a resin composite, Solare (S), as a comparison material. Moderate-depth occlusal cavities in the first permanent molars of 91 11-12-year-old children (1-4 restorations per child) were restored with either F IX (87 restorations), F IX+GCP (84 restorations) or S (83 restorations). Direct clinical assessment, photographic assessment and assessment of stone casts of the restorations were carried out at 6 months, 1 year, 2 years and 3 years. The colour match with the tooth of the GIC restorations improved over the 3 years of the study. Marginal staining and marginal adaptation were minimal for all restorations; three restorations exhibited secondary caries at 3 years. From the assessment of the casts, at 2 years, there was significantly less wear of the F IX GP Extra+GCP restorations than the F IX GP Extra restorations (P < 0.005). At 3 years, approximately 37 % of F IX GP Extra restorations showed wear slightly more than the adjacent enamel, compared to 28 % of F IX GP Extra+GCP restorations and 21 % of Solare restorations. Although this was not statistically significant, there was a trend that GCP can protect F IX GP Extra against wear. Although both Fuji IX GP Extra and Fuji IX GP Extra with G-Coat Plus showed acceptable clinical performance in occlusal cavities in children, the application of G-Coat Plus gave some protection against wear. The application of G-Coat Plus to Fuji IX GP Extra glass-ionomer cement may be beneficial in reducing wear in occlusal cavities.

Positive Selection during the Evolution of the Blood Coagulation Factors in the Context of Their Disease-Causing Mutations

PubMed Central

Rallapalli, Pavithra M.; Orengo, Christine A.; Studer, Romain A.; Perkins, Stephen J.

2014-01-01

Blood coagulation occurs through a cascade of enzymes and cofactors that produces a fibrin clot, while otherwise maintaining hemostasis. The 11 human coagulation factors (FG, FII–FXIII) have been identified across all vertebrates, suggesting that they emerged with the first vertebrates around 500 Ma. Human FVIII, FIX, and FXI are associated with thousands of disease-causing mutations. Here, we evaluated the strength of selective pressures on the 14 genes coding for the 11 factors during vertebrate evolution, and compared these with human mutations in FVIII, FIX, and FXI. Positive selection was identified for fibrinogen (FG), FIII, FVIII, FIX, and FX in the mammalian Primates and Laurasiatheria and the Sauropsida (reptiles and birds). This showed that the coagulation system in vertebrates was under strong selective pressures, perhaps to adapt against blood-invading pathogens. The comparison of these results with disease-causing mutations reported in FVIII, FIX, and FXI showed that the number of disease-causing mutations, and the probability of positive selection were inversely related to each other. It was concluded that when a site was under positive selection, it was less likely to be associated with disease-causing mutations. In contrast, sites under negative selection were more likely to be associated with disease-causing mutations and be destabilizing. A residue-by-residue comparison of the FVIII, FIX, and FXI sequence alignments confirmed this. This improved understanding of evolutionary changes in FVIII, FIX, and FXI provided greater insight into disease-causing mutations, and better assessments of the codon sites that may be mutated in applications of gene therapy. PMID:25158795

Relative effects of plasma, fibrinogen concentrate, and factor XIII on ROTEM coagulation profiles in an in vitro model of massive transfusion in trauma.

PubMed

Schmidt, David E; Halmin, Märit; Wikman, Agneta; Östlund, Anders; Ågren, Anna

2017-10-01

Massive traumatic haemorrhage is aggravated through the development of trauma-induced coagulopathy, which is managed by plasma transfusion and/or fibrinogen concentrate administration. It is yet unclear whether these treatments are equally potent in ensuring adequate haemostasis, and whether additional factor XIII (FXIII) administration provides further benefits. In this study, we compared ROTEM whole blood coagulation profiles after experimental massive transfusion with different transfusion regimens in an in vitro model of dilution- and transfusion-related coagulopathy. Healthy donor blood was mixed 1 + 1 with six different transfusion regimens. Each regimen contained RBC, platelet concentrate, and either fresh frozen plasma (FFP) or Ringer's acetate (RA). The regimens were further augmented through addition of a low- or medium-dose fibrinogen concentrate and FXIII. Transfusion with FFP alone was insufficient to maintain tissue-factor activated clot strength, coincidental with a deficiency in fibrin-based clot strength. Fibrinogen concentrate conserved, but did not improve coagulation kinetics and overall clot strength. Only combination therapy with FFP and low-dose fibrinogen concentrate improved both coagulation kinetics and fibrin-based clot strength. Administration of FXIII did not result in an improvement of clot strength. In conclusion, combination therapy with both FFP and low-dose fibrinogen concentrate improved clotting time and produced firm clots, representing a possible preferred first-line regimen to manage trauma-induced coagulopathy when RBC and platelets are also transfused. Further research is required to identify optimal first-line transfusion fluids for massive traumatic haemorrhage.

Telangiectatic Matting is Associated with Hypersensitivity and a Bleeding Tendency.

PubMed

Kadam, Pooja; Lim, Jerrick; Paver, Ian; Connor, David E; Parsi, Kurosh

2018-04-01

The aim was to investigate the pathogenesis of telangiectatic matting (TM) and identify possible risk factors. This study had two parts. The clinical records of consecutive patients were retrospectively analysed to identify risk factors for TM. In the second part, the haemostatic and coagulation profile of the subset of patients with TM were analysed and compared with controls using standard coagulation tests, platelet function and a global assay of coagulation (rotational thromboelastometry, ROTEM). In 352 consecutive patients presenting to a phlebology practice, 25 patients had TM (7.1%). All 25 patients were female with the median age of 45 (27-57) years. A comprehensive medical history was taken. Among 27 possible risk factors assessed, statistically significant associations included recurrent epistaxis, easy bruising, hypersensitivity (eczema, hives, hay fever, and rhinitis), previous treatment with sclerotherapy or endovenous laser for lower limb veins, and a family history of telangiectasias. Variables not associated with TM included oral contraceptive intake, hormone replacement therapy, and age. The haemostatic and coagulation profile of 12 patients (6 male and 6 female) with TM did not differ significantly from those without TM. TM is associated with both hypersensitivity and a bleeding tendency. This study revealed no significant increase in the incidence of haemostatic abnormalities in patients with TM compared with the control group. Given the significant association with hypersensitivity disorders, the underlying mast cell hyper-reactivity may contribute to both hypersensitivity and a bleeding tendency and predispose patients to TM. Copyright © 2017 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.

Alteration of Antithrombin III and D-dimer Levels in Clinically Localized Prostate Cancer

PubMed Central

Ko, Dong Woo; Park, Juhyun; Kim, In Sung; Doo, Seung Hwan; Yoon, Cheol Yong; Park, Hongzoo; Lee, Won Ki; Kim, Dae Sung; Jeong, Seong Jin; Byun, Seok-Soo; Lee, Sang Eun

2010-01-01

Purpose We performed a comparative analysis of the plasma levels of antithrombin (AT) III, plasminogen, fibrinogen, and D-dimer among patients with and without clinically localized prostate cancer to investigate the clinical significance of the coagulation profile in prostate cancer. Materials and Methods A prospective study was performed in which plasma levels of AT III, plasminogen, fibrinogen, and D-dimer were assessed in patients before they underwent prostate biopsy. According to the results of the biopsy, the patients were categorized into the cancer group or the control group. Levels of the four coagulation factors were then compared between the cancer and control groups. Also, levels of the four coagulation factors were correlated with tumor stage and grade in the cancer group. Results The cancer group had significantly lower levels of AT III activity and higher plasma D-dimer levels than did the control group (p=0.007 and p=0.018, respectively). Within the cancer group, no significant differences were observed in the levels of AT III, plasminogen, fibrinogen, or D-dimer between those with a pathological Gleason score of ≥7 and otherwise. Regarding pathologic stage of prostate cancer, the subjects with organ-confined disease and those with extraprostatic extension of a tumor demonstrated no significant differences in the preoperative levels of the four coagulation factors analyzed. Conclusions Our results suggest that plasma levels of AT III and D-dimer are altered in patients with prostate cancer. Further study is needed to elucidate the underlying mechanism and clinical significances of such a phenomenon among patients with clinically localized prostate cancer. PMID:20414406

Inflammatory monocytes expressing tissue factor drive SIV and HIV coagulopathy

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

Schechter, Melissa E.; Andrade, Bruno B.; He, Tianyu

In HIV infection, persistent inflammation despite effective antiretroviral therapy is linked to increased risk of noninfectious chronic complications such as cardiovascular and thromboembolic disease. Thus, a better understanding of inflammatory and coagulation pathways in HIV infection is needed to optimize clinical care. Markers of monocyte activation and coagulation independently predict morbidity and mortality associated with non-AIDS events. We identified a specific subset of monocytes that express tissue factor (TF), persist after virological suppression, and trigger the coagulation cascade by activating factor X. This subset of monocytes expressing TF had a distinct gene signature with up-regulated innate immune markers and evidencemore » of robust production of multiple proinflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor–α (TNF-α), and IL-6, ex vivo and in vitro upon lipopolysaccharide stimulation. We validated our findings in a nonhuman primate model, showing that TF-expressing inflammatory monocytes were associated with simian immunodeficiency virus (SIV)–related coagulopathy in the progressive [pigtail macaques (PTMs)] but not in the nonpathogenic (African green monkeys) SIV infection model. Last, Ixolaris, an anticoagulant that inhibits the TF pathway, was tested and potently blocked functional TF activity in vitro in HIV and SIV infection without affecting monocyte responses to Toll-like receptor stimulation. Strikingly, in vivo treatment of SIV-infected PTMs with Ixolaris was associated with significant decreases in D-dimer and immune activation. These data suggest that TF-expressing monocytes are at the epicenter of inflammation and coagulation in chronic HIV and SIV infection and may represent a potential therapeutic target.« less

Inflammatory monocytes expressing tissue factor drive SIV and HIV coagulopathy

DOE PAGES

Schechter, Melissa E.; Andrade, Bruno B.; He, Tianyu; ...

2017-08-30

In HIV infection, persistent inflammation despite effective antiretroviral therapy is linked to increased risk of noninfectious chronic complications such as cardiovascular and thromboembolic disease. Thus, a better understanding of inflammatory and coagulation pathways in HIV infection is needed to optimize clinical care. Markers of monocyte activation and coagulation independently predict morbidity and mortality associated with non-AIDS events. We identified a specific subset of monocytes that express tissue factor (TF), persist after virological suppression, and trigger the coagulation cascade by activating factor X. This subset of monocytes expressing TF had a distinct gene signature with up-regulated innate immune markers and evidencemore » of robust production of multiple proinflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor–α (TNF-α), and IL-6, ex vivo and in vitro upon lipopolysaccharide stimulation. We validated our findings in a nonhuman primate model, showing that TF-expressing inflammatory monocytes were associated with simian immunodeficiency virus (SIV)–related coagulopathy in the progressive [pigtail macaques (PTMs)] but not in the nonpathogenic (African green monkeys) SIV infection model. Last, Ixolaris, an anticoagulant that inhibits the TF pathway, was tested and potently blocked functional TF activity in vitro in HIV and SIV infection without affecting monocyte responses to Toll-like receptor stimulation. Strikingly, in vivo treatment of SIV-infected PTMs with Ixolaris was associated with significant decreases in D-dimer and immune activation. These data suggest that TF-expressing monocytes are at the epicenter of inflammation and coagulation in chronic HIV and SIV infection and may represent a potential therapeutic target.« less

Dual-channel red/blue fluorescence dosimetry with broadband reflectance spectroscopic correction measures protoporphyrin IX production during photodynamic therapy of actinic keratosis

NASA Astrophysics Data System (ADS)

Kanick, Stephen Chad; Davis, Scott C.; Zhao, Yan; Hasan, Tayyaba; Maytin, Edward V.; Pogue, Brian W.; Chapman, M. Shane

2014-07-01

Dosimetry for aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) photodynamic therapy of actinic keratosis was examined with an optimized fluorescence dosimeter to measure PpIX during treatment. While insufficient PpIX generation may be an indicator of incomplete response, there exists no standardized method to quantitate PpIX production at depths in the skin during clinical treatments. In this study, a spectrometer-based point probe dosimeter system was used to sample PpIX fluorescence from superficial (blue wavelength excitation) and deeper (red wavelength excitation) tissue layers. Broadband white light spectroscopy (WLS) was used to monitor aspects of vascular physiology and inform a correction of fluorescence for the background optical properties. Measurements in tissue phantoms showed accurate recovery of blood volume fraction and reduced scattering coefficient from WLS, and a linear response of PpIX fluorescence versus concentration down to 1.95 and 250 nM for blue and red excitations, respectively. A pilot clinical study of 19 patients receiving 1-h ALA incubation before treatment showed high intrinsic variance in PpIX fluorescence with a standard deviation/mean ratio of >0.9. PpIX fluorescence was significantly higher in patients reporting higher pain levels on a visual analog scale. These pilot data suggest that patient-specific PpIX quantitation may predict outcome response.

Dual-channel red/blue fluorescence dosimetry with broadband reflectance spectroscopic correction measures protoporphyrin IX production during photodynamic therapy of actinic keratosis

PubMed Central

Kanick, Stephen Chad; Davis, Scott C.; Zhao, Yan; Hasan, Tayyaba; Maytin, Edward V.; Pogue, Brian W.; Chapman, M. Shane

2014-01-01

Abstract. Dosimetry for aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) photodynamic therapy of actinic keratosis was examined with an optimized fluorescence dosimeter to measure PpIX during treatment. While insufficient PpIX generation may be an indicator of incomplete response, there exists no standardized method to quantitate PpIX production at depths in the skin during clinical treatments. In this study, a spectrometer-based point probe dosimeter system was used to sample PpIX fluorescence from superficial (blue wavelength excitation) and deeper (red wavelength excitation) tissue layers. Broadband white light spectroscopy (WLS) was used to monitor aspects of vascular physiology and inform a correction of fluorescence for the background optical properties. Measurements in tissue phantoms showed accurate recovery of blood volume fraction and reduced scattering coefficient from WLS, and a linear response of PpIX fluorescence versus concentration down to 1.95 and 250 nM for blue and red excitations, respectively. A pilot clinical study of 19 patients receiving 1-h ALA incubation before treatment showed high intrinsic variance in PpIX fluorescence with a standard deviation/mean ratio of >0.9. PpIX fluorescence was significantly higher in patients reporting higher pain levels on a visual analog scale. These pilot data suggest that patient-specific PpIX quantitation may predict outcome response. PMID:24996661

Mechanism of the protective effects of the combined treatment with rhynchophylla total alkaloids and sinapine thiocyanate against a prothrombotic state caused by vascular endothelial cell inflammatory damage

PubMed Central

Li, Yunlun; Zhang, Xinya; Yang, Wenqing; Li, Chao; Chu, Yanjun; Jiang, Haiqiang; Shen, Zhenzhen

2017-01-01

The aim of the present study was to investigate the effect and the underlying mechanism of the combined treatment of rhynchophylla total alkaloids (RTA) and sinapine thiocyanate for protection against a prothrombotic state (PTS) associated with the tumor necrosis factor-alpha (TNF-α)-induced inflammatory injury of vascular endothelial cells (VECs). A TNF-α-induced VEC inflammatory injury model was established, and cell morphology of VECs was evaluated using scanning electron microscopy. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to examine the mRNA and protein expression of coagulation-related factors, including nuclear factor-κB (NF-κB), transforming growth factor-β1 (TGF-β1), tissue factor (TF), plasminogen activator inhibitor (PAI-1), protease-activation receptors (PAR-1) and protein kinase C (PKC-α) in VECs. Combined treatment with RTA and sinapine thiocyanate was demonstrated to reduce, to a varying extent, the mRNA and protein expression of NF-κB, TGF-β1, TF, PAR-1, PKC-α and PAI-1. Furthermore, combined treatment with RTA and sinapine thiocyanate was able to downregulate the expression of coagulation-related factors in injured VECs, thereby inhibiting the PTS induced by vascular endothelial injury. The underlying mechanism is partially associated with the TF-mediated activation of the thrombin-receptor signaling pathway that suppresses coagulation during inflammation and balances fibrinolysis in order to inhibit fibrin generation and deposition. PMID:28587383

Mechanism of the protective effects of the combined treatment with rhynchophylla total alkaloids and sinapine thiocyanate against a prothrombotic state caused by vascular endothelial cell inflammatory damage.

PubMed

Li, Yunlun; Zhang, Xinya; Yang, Wenqing; Li, Chao; Chu, Yanjun; Jiang, Haiqiang; Shen, Zhenzhen

2017-06-01

The aim of the present study was to investigate the effect and the underlying mechanism of the combined treatment of rhynchophylla total alkaloids (RTA) and sinapine thiocyanate for protection against a prothrombotic state (PTS) associated with the tumor necrosis factor-alpha (TNF-α)-induced inflammatory injury of vascular endothelial cells (VECs). A TNF-α-induced VEC inflammatory injury model was established, and cell morphology of VECs was evaluated using scanning electron microscopy. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to examine the mRNA and protein expression of coagulation-related factors, including nuclear factor-κB (NF-κB), transforming growth factor-β1 (TGF-β1), tissue factor (TF), plasminogen activator inhibitor (PAI-1), protease-activation receptors (PAR-1) and protein kinase C (PKC-α) in VECs. Combined treatment with RTA and sinapine thiocyanate was demonstrated to reduce, to a varying extent, the mRNA and protein expression of NF-κB, TGF-β1, TF, PAR-1, PKC-α and PAI-1. Furthermore, combined treatment with RTA and sinapine thiocyanate was able to downregulate the expression of coagulation-related factors in injured VECs, thereby inhibiting the PTS induced by vascular endothelial injury. The underlying mechanism is partially associated with the TF-mediated activation of the thrombin-receptor signaling pathway that suppresses coagulation during inflammation and balances fibrinolysis in order to inhibit fibrin generation and deposition.

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.

[Role and clinical significance of coagulation and inflammatory factors in moderate and severe ovarian endometriosis].

PubMed

Lin, Q; Ding, S J; Zhu, T H; Li, T T; Huang, X F; Zhang, X M

2018-03-25

Objective: To determine the levels of coagulation and inflammatory factors in women with moderate and severe ovarian endometriosis so as to investigate the possible role of coagulation and inflammatory factors in the pathogenesis, diagnosis and treatment of this disease. Methods: From June 2015 and June 2017, clinical data of 366 patients with pathologically diagnosed moderate and severe ovarian endometriosis (case group) and 244 patients with pathologically diagnosed benign ovarian cysts (control group) in Women's Hospital of Zhejiang University School of Medicine were retrospectively analyzed. The levels of coagulation indicators, inflammatory factors and serum tumor markers were measured. Then, the values of these indicators in diagnosis of endometriosis were analyzed. Results: (1) The levels of plasma prothrombin time (PT) and thrombin time (TT) in patients with ovarian endometriosis [median: 12.8 s (range: 12.4-13.2 s) and 15.5 s (range: 15.1-15.9 s), respectively] were significantly shorter than those with benign ovarian cysts [median: 13.0 s (range: 12.5-13.4 s) and 15.7 s (range: 15.3-16.1 s), respectively; all P <0.01]. The levels of plasma fibrinogen (FIB) and D-dimer [D-D; median: 3.1 g/L (range: 2.8-3.5 g/L) and 0.9 mg/L (range: 0.6-2.1 mg/L) , respectively] in patients with ovarian endometriosis were significantly higher than those with benign ovarian cysts [median: 2.8 g/L (range: 2.6-3.2 g/L) and 0.6 mg/L (range: 0.4-1.2 mg/L), respectively; P =0.000]. Moreover, neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio [PLR; median: 2.3 (range: 1.8-3.1) and 144 (range: 113-179), respectively] in patients with ovarian endometriosis were significantly higher than those with benign ovarian cysts [median: 2.1 (range: 1.6-2.8) and 128 (range: 104-165), respectively; P <0.01]. Furthermore, in patients with ovarian endometriosis, the levels of PT were significantly shorter in stage Ⅳ endometriosis than that in stage Ⅲ endometriosis ( P <0.05). The levels of FIB and PLR in patients with stage Ⅳ endometriosis were significantly higher than those in patients with stage Ⅲ endometriosis ( P <0.01) . (2) The cut-off value of CA(125) was 27.2 kU/L with a sensitivity of 83.6%, the cut-off value of FIB was 3.1 g/L with a sensitivity of 53.2%, while the sensitivity of combination index (FIB×CA(125)) was 84.9%. Conclusion: The abnormality of coagulation and inflammatory factors may be involved in the pathogenesis of moderate and severe ovarian endometriosis, and the detection of coagulation and inflammatory factors may be have important clinical significance for the diagnosis and treatment of moderate and severe ovarian endometriosis.

An update on anticancer drug development and delivery targeting carbonic anhydrase IX

PubMed Central

Parkkila, Seppo

2017-01-01

The expression of carbonic anhydrase (CA) IX is up-regulated in many types of solid tumors in humans under hypoxic and acidic microenvironment. Inhibition of CA IX enzymatic activity with selective inhibitors, antibodies or labeled probes has been shown to reverse the acidic environment of solid tumors and reduce the tumor growth establishing the significant role of CA IX in tumorigenesis. Thus, the development of potent antitumor drugs targeting CA IX with minimal toxic effects is important for the target-specific tumor therapy. Recently, several promising antitumor agents against CA IX have been developed to treat certain types of cancers in combination with radiation and chemotherapy. Here we review the inhibition of CA IX by small molecule compounds and monoclonal antibodies. The methods of enzymatic assays, biophysical methods, animal models including zebrafish and Xenopus oocytes, and techniques of diagnostic imaging to detect hypoxic tumors using CA IX-targeted conjugates are discussed with the aim to overview the recent progress related to novel therapeutic agents that target CA IX in hypoxic tumors. PMID:29181278

The spectroscopy analyses of PpIX by ultrasound irradiation and its sonotoxicity in vitro.

PubMed

Wang, Pan; Wang, Xiaobing; Zhang, Kun; Gao, Kaili; Song, Ming; Liu, Quanhong

2013-07-01

Protoporphyrin IX (PpIX) has been used as a sensitizer in photodynamic therapy (PDT) as well as in sonodynamic therapy (SDT). The photo-bleaching of PpIX has been well investigated in many experimental systems and some photo-products have also been identified in PDT. But until now, little information has been reported about the sono-damage of PpIX in SDT. So, the present study was to investigate changes of PpIX properties before and after different ultrasound treatment, and the potential interactions between PpIX, ultrasound and the irradiated cells. In cell-free system, the absorption and fluorescence spectra of PpIX in different solutions were measured by ultraviolet spectrometer and fluorescence spectrophotometer, respectively. The terephthalic acid dosimetry was applied to evaluate the efficiency of ultrasound cavitation by monitoring hydroxyl radical (OH) production on the thermolysis of H2O in the ultrasound field. In in vitro study, confocal microscopy was applied to detect the sub-cellular localization of PpIX in S180 cells before and after ultrasound exposure. Flow cytometry was used to detect the reactive oxygen species (ROS) generation during PpIX-SDT. MTT assay was performed to evaluate the cell viability of S180 cells after SDT treatment with or without ROS scavengers. The results show that PpIX displayed different spectral patterns in different solutions. PpIX was decomposed by ultrasound exposure as measured by the decreased absorption and fluorescence peak values in RPMI-1640 medium. In addition, the decomposition of PpIX was found to be simultaneously accompanied by OH production with increasing output power from ultrasound generator. PpIX at 1μg/ml significantly enhanced the ultrasound induced cavitation as measured by OH generation, and which was greatly eliminated by NaN3, histidine, mannitol, EDTA and catalase, but not by SOD. The in vitro study indicates more PpIX entered into S180 cells after ultrasound exposure. And, the extra-cellular PpIX play an important role in the enhanced cell killing of PpIX-SDT. SDT induced obvious ROS generation in S180 cells, which could be mostly inhibited by the general ROS scavenge NAC (N-acetylcysteine). Other scavengers such as NaN3, histidine, mannitol all partially prevented the SDT induced cell viability loss of S180 cells, suggesting OH, (1)O2 might be involved during the process. Copyright © 2012 Elsevier B.V. All rights reserved.

Betrixaban: Impact on Routine and Specific Coagulation Assays-A Practical Laboratory Guide.

PubMed

Siriez, Romain; Evrard, Jonathan; Dogné, Jean-Michel; Pochet, Lionel; Gheldof, Damien; Chatelain, Bernard; Mullier, François; Douxfils, Jonathan

2018-06-11

 Betrixaban is a novel direct oral factor Xa inhibitor approved by the Food and Drug Administration for prophylaxis of venous thromboembolism in adult patients hospitalized for an acute illness at risk for thromboembolic complications. Assessment of the anti-coagulant effect of betrixaban may be useful in some situations. Also, clinicians need to know how routine coagulation assays are influenced.  The aim of this study is to determine which coagulation assay(s) should be used to assess the impact of betrixaban on haemostasis and provide laboratory guidance for their interpretation.  Betrixaban was spiked at final concentrations ranging from 0 to 250 ng/mL in platelet-poor plasma. Different reagents from several manufacturers were tested and the impact of betrixaban on pro-thrombin time (PT), activated partial thromboplastin time (aPTT), dilute Russel viper venom time (dRVV-T), chromogenic anti-Xa assays, thrombin generation assay (TGA), and a large panel of haemostasis diagnostic tests has been assessed.  A concentration-dependent prolongation of aPTT, PT and dRVV-T is observed. The sensitivity mainly depends on the reagent. Chromogenic anti-Xa assays show high sensitivity depending on the reagent and/or the methodology. These assays applicable for other direct factor Xa inhibitors have to be adapted to obtain a relevant range of measurement. TGA may also be attractive to assess the anti-coagulant activity of betrixaban.  Adapted chromogenic anti-Xa assays are the most appropriate assays to estimate the concentration of betrixaban. Betrixaban significantly affects several haemostasis diagnostic tests and this needs to be taken into consideration when requesting and interpreting such tests. Schattauer GmbH Stuttgart.

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.

The Role of Title IX Coordinators on College and University Campuses

PubMed Central

Wiersma-Mosley, Jacquelyn D.; DiLoreto, James

2018-01-01

The purpose of this study was to better understand the role of Title IX coordinators and their policies across four-year universities and two-year community colleges in the United States (U.S.). There is little information regarding Title IX coordinators’ training, background, and policies on how they handle Title IX investigations regarding sexual violence. The data come from an online survey that included 692 Title IX coordinators across four-year (private and public) and two-year campuses and represented 42 different states in the US. The current study found that most Title IX coordinators were in part-time positions with less than three years of experience. Most of the coordinators and their investigators were trained in Title IX policies. Most coordinators provide Title IX training for their students and faculty, and most have completed a campus climate survey; however, 15% had not completed a survey. The findings suggest that the majority of campuses are continuing to increase their Title IX visibility; however, there are several recommendations for campuses to improve their policies. The current study was able to shed light on how Title IX coordinators do their jobs and the role they play in helping with the challenging issues surrounding sexual violence at institutions across the nation. PMID:29621177

Study on the blood compatibility and biodegradation properties of magnesium alloys.

PubMed

Mochizuki, Akira; Kaneda, Hideki

2015-02-01

Lately, several magnesium alloys have been investigated as a new class of biomaterials owing to their excellent biodegradability in living tissues. In this study, we considered AZ series of Mg alloy containing aluminum (3% to 9%) and zinc (1%) as a model magnesium alloy, and investigated their biodegradation in whole blood and blood compatibility in vitro. The results of the elution property of metal ions determined using chromogenic assay and the associated pH change show that the degradation resistance of the AZ series alloys in blood is improved by alloying aluminum. Furthermore, the blood compatibility of the alloys was investigated in terms of their hemolysis, factor Xa-like activity, using spectrophotometry and chromogenic assay, respectively, and coagulation time measurements (prothrombin time and activated partial thromboplastin time). The results indicated that the blood compatibility of the AZ series alloys is excellent, irrespective of the alloy composition. The excellent blood compatibility with the coagulation system could be attributed to the eluted Mg(2+) ion, which suppresses the activation of certain coagulation factors in the intrinsic and/or extrinsic coagulation pathways. In terms of the degradation resistance of the AZ series alloys in blood, the results of pH change in blood and the amount of the eluted metal ions indicate that the performance is markedly improved with an increase in aluminum content. Copyright © 2014 Elsevier B.V. All rights reserved.

Local activation of coagulation factor XIII reduces systemic complications and improves the survival of mice after Streptococcus pyogenes M1 skin infection.

PubMed

Deicke, Christin; Chakrakodi, Bhavya; Pils, Marina C; Dickneite, Gerhard; Johansson, Linda; Medina, Eva; Loof, Torsten G

2016-11-01

Coagulation is a mechanism for wound healing after injury. Several recent studies delineate an additional role of the intrinsic pathway of coagulation, also known as the contact system, in the early innate immune response against bacterial infections. In this study, we investigated the role of factor XIII (FXIII), which is activated upon coagulation induction, during Streptococcus pyogenes-mediated skin and soft tissue infections. FXIII has previously been shown to be responsible for the immobilization of bacteria within a fibrin network which may prevent systemic bacterial dissemination. In order to investigate if the FXIII-mediated entrapment of S. pyogenes also influences the disease outcome we used a murine S. pyogenes M1 skin and soft tissue infection model. Here, we demonstrate that a lack of FXIII leads to prolonged clotting times, increased signs of inflammation, and elevated bacterial dissemination. Moreover, FXIII-deficient mice show an impaired survival when compared with wildtype animals. Additionally, local reconstitution of FXIII-deficient mice with a human FXIII-concentrate (Fibrogammin ® P) could reduce the systemic complications, suggesting a protective role for FXIII during early S. pyogenes skin infection. FXIII therefore might be a possible therapeutically application to support the early innate immune response during skin infections caused by S. pyogenes. Copyright © 2016 Elsevier GmbH. All rights reserved.

Targeted inactivation of the mouse locus encoding coagulation factor XIII-A: hemostatic abnormalities in mutant mice and characterization of the coagulation deficit.

PubMed

Lauer, Peter; Metzner, Hubert J; Zettlmeissl, Gerd; Li, Meng; Smith, Austin G; Lathe, Richard; Dickneite, Gerhard

2002-12-01

Blood coagulation factor XIII (FXIII) promotes cross-linking of fibrin during blood coagulation; impaired clot stabilization in human genetic deficiency is associated with marked pathologies of major clinical impact, including bleeding symptoms and deficient wound healing. To investigate the role of FXIII we employed homologous recombination to generate a targeted deletion of the inferred exon 7 of the FXIII-A gene. FXIII transglutaminase activity in plasma was reduced to about 50% in mice heterozygous for the mutant allele, and was abolished in homozygous null mice. Plasma fibrin gamma-dimerization was also indetectable in the homozygous deficient animals, confirming the absence of activatable FXIII. Homozygous mutant mice were fertile, although reproduction was impaired. Bleeding episodes, hematothorax, hematoperitoneum and subcutaneous hemorrhage in mutant mice were associated with reduced survival. Arrest of tail-tip bleeding in FXIII-A deficient mice was markedly and significantly delayed; replacement of mutant mice with human plasma FXIII (Fibrogammin P) restored bleeding time to within the normal range. Thrombelastography (TEG) experiments demonstrated impaired clot stabilization in FXIII-A mutant mice, replacement with human FXIII led to dose-dependent TEG normalization. The mutant mice thus reiterate some key features of the human genetic disorder: they will be valuable in assessing the role of FXIII in other associated pathologies and the development of new therapies.

The Mast Cell, Contact, and Coagulation System Connection in Anaphylaxis

PubMed Central

Guilarte, Mar; Sala-Cunill, Anna; Luengo, Olga; Labrador-Horrillo, Moisés; Cardona, Victoria

2017-01-01

Anaphylaxis is the most severe form of allergic reaction, resulting from the effect of mediators and chemotactic substances released by activated cells. Mast cells and basophils are considered key players in IgE-mediated human anaphylaxis. Beyond IgE-mediated activation of mast cells/basophils, further mechanisms are involved in the occurrence of anaphylaxis. New insights into the potential relevance of pathways other than mast cell and basophil degranulation have been unraveled, such as the activation of the contact and the coagulation systems. Mast cell heparin released upon activation provides negatively charged surfaces for factor XII (FXII) binding and auto-activation. Activated FXII, the initiating serine protease in both the contact and the intrinsic coagulation system, activates factor XI and prekallikrein, respectively. FXII-mediated bradykinin (BK) formation has been proven in the human plasma of anaphylactic patients as well as in experimental models of anaphylaxis. Moreover, the severity of anaphylaxis is correlated with the increase in plasma heparin, BK formation and the intensity of contact system activation. FXII also activates plasminogen in the fibrinolysis system. Mast cell tryptase has been shown to participate in fibrinolysis through plasmin activation and by facilitating the degradation of fibrinogen. Some usual clinical manifestations in anaphylaxis, such as angioedema or hypotension, or other less common, such as metrorrhagia, may be explained by the direct effect of the activation of the coagulation and contact system driven by mast cell mediators. PMID:28798744

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

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.

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.

A sucrose-binding site provides a lead towards an isoform-specific inhibitor of the cancer-associated enzyme carbonic anhydrase IX

DOE PAGES

Pinard, Melissa A.; Aggarwal, Mayank; Mahon, Brian P.; ...

2015-09-23

Human carbonic anhydrase (CA; EC 4.2.1.1) isoform IX (CA IX) is an extracellular zinc metalloenzyme that catalyzes the reversible hydration of CO 2to HCO 3 $-$, thereby playing a role in pH regulation. The majority of normal functioning cells exhibit low-level expression of CA IX. However, in cancer cells CA IX is upregulated as a consequence of a metabolic transition known as the Warburg effect. The upregulation of CA IX for cancer progression has drawn interest in it being a potential therapeutic target. CA IX is a transmembrane protein, and its purification, yield and crystallization have proven challenging to structure-basedmore » drug design, whereas the closely related cytosolic soluble isoform CA II can be expressed and crystallized with ease. Therefore, we have utilized structural alignments and site-directed mutagenesis to engineer a CA II that mimics the active site of CA IX. In this paper, the X-ray crystal structure of this CA IX mimic in complex with sucrose is presented and has been refined to a resolution of 1.5 Å, anR cryst of 18.0% and anR free of 21.2%. Finally, the binding of sucrose at the entrance to the active site of the CA IX mimic, and not CA II, in a non-inhibitory mechanism provides a novel carbohydrate moiety binding site that could be further exploited to design isoform-specific inhibitors of CA IX.« less

[The blood coagulation system and microcirculatory disorders in ixodid tick-borne borreliosis caused by Borrelia miyamotoi].

PubMed

Platonov, A E; Sarksyan, D S; Karan, L S; Shipulin, G A; Gordygina, E V; Malinin, O V; Maleev, V V

2015-01-01

To study blood coagulation and microcirculatory disorders as a possible cause of transient dysfunctions of organs (the kidney, liver, heart, lung, etc.) in patients with ixodid tick-borne borreliosis caused by Borrelia miyamotoi (Bmt). SUBJECTS AND METHODS; Twenty-four patients with Lyme disease (LD) and 28 Bmt patients treated at Izhevsk City Hospital (Udmurtia) were examined in the study. Platelet counts and the presence of D-dimers were determined; activated partial thromboplastin time, prothrombin time, thrombin time, fibrinogen and antithrombin III levels, and Factor XIIa-dependent fibrin clot lysis time were measured. Slit lamp microscopy of the conjunctiva was. also carried out. Results. Platelet counts'were less than 150,000 per pL of blood in 43% of the Bmt patients. All the Bmt patients had at least one abnormal coagulation parameter of the eight ones that were tested; 64% of them had marked coagulation disorders with three or more abnormal laboratory findings. In contrast, all the eight parameters were normal in 71% of the LD patients. The other seven LD patients had only one or two abnormal coagulation parameters (p < 0.001 in comparison with Bmt patients). Microscopic examination of eye capillary blood flow revealed pathological findings that included aggregates of erythrocytes and obstructed and/or sinuous capillaries in 22 (79%) of the Bmt patients, but none of the LD patients. A total of 14 Bmt patients had both coagulation and microcirculatory abnormalities. Eleven of them also had transient signs of organ dysfunction. As far as Borrelia secrete no known toxins, we hypothesized that uncovered disorders of blood coagulation and microcirculation in Bmt patients may contribute to organ dysfunction.

Reconsidering the Status of Title IX.

ERIC Educational Resources Information Center

Hammer, Ben

2003-01-01

Discusses the controversy over Title IX and women's participation in college athletics. Critics say the mandate shortchanges men's teams, while proponents say that women's sports programs remain underfunded in spite of Title IX. Describes some proposed modifications to Title IX and their potential effects. (SLD)

Enhanced Functional Recombinant Factor VII Production by HEK 293 Cells Stably Transfected with VKORC1 where the Gamma-Carboxylase Inhibitor Calumenin is Stably Suppressed by shRNA Transfection

PubMed Central

Wajih, Nadeem; Owen, John; Wallin, Reidar

2008-01-01

Introduction Recombinant members of the vitamin K-dependent protein family (factors IX and VII and protein C) have become important pharmaceuticals in treatment of bleeding disorders and sepsis. However, because the in vivo γ-carboxylation system in stable cell lines used for transfection has a limited capacity of post translational γ carboxylation, the recovery of fully γ-carboxylated and functional proteins is low. Materials and Methods In this work we have engineered recombinant factor VII producing HEK 293 cells to stably overexpress VKORC1, the reduced vitamin K γ-carboxylase cofactor and in addition stably silenced the γ-carboxylase inhibitory protein calumenin. Results and Conclusions Stable cell lines transfected with only a factor VII cDNA had a 9% production of functional recombinant factor VII. On the other hand, these recombinant factor VII producing cells when engineered to overexpress VKORC1 and having calumenin stably suppressed more than 80% by shRNA expression, produced 68% functional factor VII. The technology presented should be applicable to all vertebrae members of the vitamin K-dependent protein family and should lower the production cost of the clinically used factors VII, IX and protein C. PMID:18177690

[Serum vitamin K concentration and nutrition].

PubMed

Tsugawa, Naoko; Okano, Toshio

2007-11-01

Vitamin K (VK) is well known for its role in the synthesis of a number of blood coagulation factors. VK is also an important factor for bone metabolism via gamma-carboxylation of VK-dependent proteins such as osteocalcin, matrix Gla protein, and protein S. Recently, it is rare that severe VK deficiency is observed. However, low dietary VK intake or low VK status has been shown to be associated with low bone mineral density and increased hip fracture risk. These studies suggest that there is potential VK insufficiency in bone, even in sufficient VK status for blood coagulation. In the present review, the studies concerning relationship between serum VK concentration and bone health, including pharmacokinetics of VK analogues (such as phylloquinone and menaquinone) and factors which affect on blood circulation of VK, are reviewed.

Determination of dabigatran, rivaroxaban and apixaban by ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) and coagulation assays for therapy monitoring of novel direct oral anticoagulants.

PubMed

Schmitz, E M H; Boonen, K; van den Heuvel, D J A; van Dongen, J L J; Schellings, M W M; Emmen, J M A; van der Graaf, F; Brunsveld, L; van de Kerkhof, D

2014-10-01

Three novel direct oral anticoagulants (DOACs) have recently been registered by the Food and Drug Administration and European Medicines Agency Commission: dabigatran, rivaroxaban, and apixaban. To quantify DOACs in plasma, various dedicated coagulation assays have been developed. To develop and validate a reference ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) method and to evaluate the analytical performance of several coagulation assays for quantification of dabigatran, rivaroxaban, and apixaban. The developed UPLC-MS/MS method was validated by determination of precision, accuracy, specificity, matrix effects, lower limits of detection, carry-over, recovery, stability, and robustness. The following coagulation assays were evaluated for accuracy and precision: laboratory-developed (LD) diluted thrombin time (dTT), Hemoclot dTT, Pefakit PiCT, ECA, Liquid anti-Xa, Biophen Heparin (LRT), and Biophen DiXal anti-Xa. Agreement between the various coagulation assays and UPLC-MS/MS was determined with random samples from patients using dabigatran or rivaroxaban. The UPLC-MS/MS method was shown to be accurate, precise, sensitive, stable, and robust. The dabigatran coagulation assay showing the best precision, accuracy and agreement with the UPLC-MS/MS method was the LD dTT test. For rivaroxaban, the anti-factor Xa assays were superior to the PiCT-Xa assay with regard to precision, accuracy, and agreement with the reference method. For apixaban, the Liquid anti-Xa assay was superior to the PiCT-Xa assay. Statistically significant differences were observed between the various coagulation assays as compared with the UPLC-MS/MS reference method. It is currently unknown whether these differences are clinically relevant. When DOACs are quantified with coagulation assays, comparison with a reference method as part of proficiency testing is therefore pivotal. © 2014 International Society on Thrombosis and Haemostasis.

Ambient hemolysis and activation of coagulation is different between HeartMate II and HeartWare left ventricular assist devices.

PubMed

Birschmann, Ingvild; Dittrich, Marcus; Eller, Thomas; Wiegmann, Bettina; Reininger, Armin J; Budde, Ulrich; Strüber, Martin

2014-01-01

Thromboembolic and bleeding events in patients with a left ventricular assist device (LVAD) are still a major cause of complications. Therefore, the balance between anti-coagulant and pro-coagulant factors needs to be tightly controlled. The principle hypothesis of this study is that different pump designs may have an effect on hemolysis and activation of the coagulation system. Referring to this, the HeartMate II (HMII; Thoratec Corp, Pleasanton, CA) and the HeartWare HVAD (HeartWare International Inc, Framingham, MA) were investigated. For 20 patients with LVAD support (n = 10 each), plasma coagulation, full blood count, and clinical chemistry parameters were measured. Platelet function was monitored using platelet aggregometry, platelet function analyzer-100 system ( Siemens, Marburg, Germany), vasodilator-stimulated phosphoprotein phosphorylation assay, immature platelet fraction, platelet-derived microparticles, and von Willebrand diagnostic. Acquired von Willebrand syndrome could be detected in all patients. Signs of hemolysis, as measured by lactate dehydrogenase levels (mean, 470 U/liter HMII, 250 U/liter HVAD; p < 0.001), were more pronounced in the HMII patients. In contrast, D-dimer analysis indicated a significantly higher activation of the coagulation system in HVAD patients (mean, 0.94 mg/liter HMII, 2.01 mg/liter HVAD; p < 0.01). The efficacy of anti-platelet therapy using clopidogrel was not sufficient in more than 50% of the patients. Our results support the finding that all patients with rotary blood pumps suffered from von Willebrand syndrome. In addition, a distinct footprint of effects on hemolysis and the coagulation system can be attributed to different devices. As a consequence, the individual status of the coagulation system needs to be controlled in long-term patients. © 2013 Published by International Society for the Heart and Lung Transplantation on behalf of International Society for Heart and Lung Transplantation.

A data-driven approach for the study of coagulation phenomena in waste lubricant oils and its relevance in alkaline regeneration treatments.

PubMed

Pinheiro, C T; Ascensão, V R; Reis, M S; Quina, M J; Gando-Ferreira, L M

2017-12-01

Coagulation phenomena can occur in certain types of waste lubricant oils (WLO) during regeneration processes involving alkaline treatments, causing plant shutdowns. In this context, this study addresses the nature of the compounds responsible for the coagulation phenomena after the alkaline treatment. For such, an empirical test was developed to assess the coagulation behaviour of WLO, consisting in the addition of KOH to the WLO followed by heating under stirring conditions. This test was performed on 133 samples and four coagulation classes were identified: A; B1; B2 and C. Moreover, a physicochemical characterization of WLO was carried out regarding viscosity at 40°C, saponification number (SN), total acid number (TAN), surface tension, water content, elemental analysis and functional groups (FTIR). 56 samples of fresh lubricant oils for different applications were also characterized and their properties assessed and compared. Multivariate methods were applied to WLO to discriminate among coagulation classes based on FTIR spectra. It was found that coagulation classes A and B1 exhibit statistically similar patterns for all properties determined. Spectral discriminating analysis did not reveal discriminant peaks for class B1 samples, and the presence of specific additives was pointed as the possible factor underlying the increase in viscosity in this oils. Class B2 presents the absence of additives and oxidation products as differentiating features. In addition, B2 samples showed lower TAN SN, and lower concentration of some elements. Lubricants from gear or hydraulic applications can give rise to this class of WLO. Oils of Class C are mainly composed by synthetic ester type base oils, which hamper regeneration processes using alkaline pretreatments. In future studies, WLO type A and B1 can be classified as a single class. The coagulation phenomena classification becomes A - negative, B - precipitate formation and C - positive. Copyright © 2017 Elsevier B.V. All rights reserved.

Coagulation management in patients undergoing neurosurgical procedures.

PubMed

Robba, Chiara; Bertuetti, Rita; Rasulo, Frank; Bertuccio, Alessando; Matta, Basil

2017-10-01

Management of coagulation in neurosurgical procedures is challenging. In this contest, it is imperative to avoid further intracranial bleeding. Perioperative bleeding can be associated with a number of factors, including anticoagulant drugs and coagulation status but is also linked to the characteristic and the site of the intracranial disorder. The aim of this review will be to focus primarily on the new evidence regarding the management of coagulation in patients undergoing craniotomy for neurosurgical procedures. Antihemostatic and anticoagulant drugs have shown to be associated with perioperative bleeding. On the other hand, an increased risk of venous thromboembolism and hypercoagulative state after elective and emergency neurosurgery, in particular after brain tumor surgery, has been described in several patients. To balance the risk between thrombosis and bleeding, it is important to be familiar with the perioperative changes in coagulation and with the recent management guidelines for anticoagulated patients undergoing neurosurgical procedures, in particular for those taking new direct anticoagulants. We have considered the current clinical trials and literature regarding both safety and efficacy of deep venous thrombosis prophylaxis in the neurosurgical population. These were mainly trials concerning both elective surgical and intensive care patients with a poor grade intracranial bleed or multiple traumas with an associated severe traumatic brain injury (TBI). Coagulation management remains a major issue in patients undergoing neurosurgical procedures. However, in this field of research, literature quality is poor and further studies are necessary to identify the best strategies to minimize risks in this group of patients.

Coagulation activation in autoimmune bullous diseases

PubMed Central

Marzano, A V; Tedeschi, A; Spinelli, D; Fanoni, D; Crosti, C; Cugno, M

2009-01-01

The main autoimmune blistering skin disorders are pemphigus vulgaris (PV) and bullous pemphigoid (BP). They differ in the inflammatory infiltrate, which is more intense in BP. Inflammation is known to activate coagulation in several disorders. Local and systemic activation of coagulation was evaluated in BP and PV. We studied 20 BP patients (10 active and 10 remittent), 23 PV patients (13 active and 10 remittent) and 10 healthy subjects. The coagulation markers prothrombin fragment F1+2 and D-dimer were measured by enzyme-immunoassays in plasma. The presence of tissue factor (TF), the main initiator of blood coagulation, was evaluated immunohistochemically in skin specimens from 10 patients with active PV, 10 patients with active BP and 10 controls. Plasma F1+2 and D-dimer levels were significantly high in active BP (P = 0·001), whereas in active PV the levels were normal. During remission, F1+2 and D-dimer plasma levels were normal in both BP and PV. TF immunoreactivity was found in active BP but neither in active PV nor in normal skin. TF reactivity scores were higher in active BP than in controls or active PV (P = 0·0001). No difference in TF scores was found between active PV and controls. BP is associated with coagulation activation, which is lacking in PV. This suggests that BP but not PV patients have an increased thrombotic risk. The observation that thrombotic complications occur more frequently in BP than in PV further supports this view. PMID:19737228

Scanning Fiber Endoscope Improves Detection of 5-Aminolevulinic Acid-Induced Protoporphyrin IX Fluorescence at the Boundary of Infiltrative Glioma.

PubMed

Belykh, Evgenii; Miller, Eric J; Hu, Danying; Martirosyan, Nikolay L; Woolf, Eric C; Scheck, Adrienne C; Byvaltsev, Vadim A; Nakaji, Peter; Nelson, Leonard Y; Seibel, Eric J; Preul, Mark C

2018-05-01

Fluorescence-guided surgery with protoporphyrin IX (PpIX) as a photodiagnostic marker is gaining acceptance for resection of malignant gliomas. Current wide-field imaging technologies do not have sufficient sensitivity to detect low PpIX concentrations. We evaluated a scanning fiber endoscope (SFE) for detection of PpIX fluorescence in gliomas and compared it to an operating microscope (OPMI) equipped with a fluorescence module and to a benchtop confocal laser scanning microscope (CLSM). 5-Aminolevulinic acid-induced PpIX fluorescence was assessed in GL261-Luc2 cells in vitro and in vivo after implantation in mouse brains, at an invading glioma growth stage, simulating residual tumor. Intraoperative fluorescence of high and low PpIX concentrations in normal brain and tumor regions with SFE, OPMI, CLSM, and histopathology were compared. SFE imaging of PpIX correlated to CLSM at the cellular level. PpIX accumulated in normal brain cells but significantly less than in glioma cells. SFE was more sensitive to accumulated PpIX in fluorescent brain areas than OPMI (P < 0.01) and dramatically increased imaging time (>6×) before tumor-to-background contrast was diminished because of photobleaching. SFE provides new endoscopic capabilities to view PpIX-fluorescing tumor regions at cellular resolution. SFE may allow accurate imaging of 5-aminolevulinic acid labeling of gliomas and other tumor types when current detection techniques have failed to provide reliable visualization. SFE was significantly more sensitive than OPMI to low PpIX concentrations, which is relevant to identifying the leading edge or metastasizing cells of malignant glioma or to treating low-grade gliomas. This new application has the potential to benefit surgical outcomes. Copyright © 2018 Elsevier Inc. All rights reserved.

Hemophilia

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 ...

Physiological oxygen concentration alters glioma cell malignancy and responsiveness to photodynamic therapy in vitro.

PubMed

Albert, Ina; Hefti, Martin; Luginbuehl, Vera

2014-11-01

The partial pressure of oxygen (pO2) in brain tumors ranges from 5 to 15%. Nevertheless, the majority of in vitro experiments with glioblastoma multiforme (GBM) cell lines are carried out under an atmospheric pO2 of 19 to 21%. Recently, 5-aminolevulinic acid (5-ALA), a precursor of protoporphyrin IX (PpIX), has been introduced to neurosurgery to allow for photodynamic diagnosis and photodynamic therapy (PDT) in high-grade gliomas. Here, we investigate whether low pO2 affects GBM cell physiology, PpIX accumulation, or PDT efficacy. GBM cell lines (U-87 MG and U-251 MG) were cultured under atmospheric (pO2  =  19%) and physiological (pO2  =  9%) oxygen concentrations. PpIX accumulation and localization were investigated, and cell survival and cell death were observed following in vitro PDT. A physiological pO2 of 9% stimulated GBM cell migration, increased hypoxia-inducible factor (HIF)-1 alpha levels, and elevated resistance to camptothecin in U-87 MG cells compared to cultivation at a pO2 of 19%. This oxygen reduction did not alter 5-ALA-induced intracellular PpIX accumulation. However, physiological pO2 changed the responsiveness of U-87 MG but not of U-251 MG cells to in vitro PDT. Around 20% more irradiation light was required to kill U-87 MG cells at physiological pO2, resulting in reduced lactate dehydrogenase (LDH) release (one- to two-fold) and inhibition of caspase 3 activation. Reduction of oxygen concentration from atmospheric to a more physiological level can influence the malignant behavior and survival of GBM cell lines after in vitro PDT. Therefore, precise oxygen concentration control should be considered when designing and performing experiments with GBM cells.

Comparative Proteomic Analysis of Normal and Collagen IX Null Mouse Cartilage Reveals Altered Extracellular Matrix Composition and Novel Components of the Collagen IX Interactome*

PubMed Central

Brachvogel, Bent; Zaucke, Frank; Dave, Keyur; Norris, Emma L.; Stermann, Jacek; Dayakli, Münire; Koch, Manuel; Gorman, Jeffrey J.; Bateman, John F.; Wilson, Richard

2013-01-01

The cartilage extracellular matrix is essential for endochondral bone development and joint function. In addition to the major aggrecan/collagen II framework, the interacting complex of collagen IX, matrilin-3, and cartilage oligomeric matrix protein (COMP) is essential for cartilage matrix stability, as mutations in Col9a1, Col9a2, Col9a3, Comp, and Matn3 genes cause multiple epiphyseal dysplasia, in which patients develop early onset osteoarthritis. In mice, collagen IX ablation results in severely disturbed growth plate organization, hypocellular regions, and abnormal chondrocyte shape. This abnormal differentiation is likely to involve altered cell-matrix interactions but the mechanism is not known. To investigate the molecular basis of the collagen IX null phenotype we analyzed global differences in protein abundance between wild-type and knock-out femoral head cartilage by capillary HPLC tandem mass spectrometry. We identified 297 proteins in 3-day cartilage and 397 proteins in 21-day cartilage. Components that were differentially abundant between wild-type and collagen IX-deficient cartilage included 15 extracellular matrix proteins. Collagen IX ablation was associated with dramatically reduced COMP and matrilin-3, consistent with known interactions. Matrilin-1, matrilin-4, epiphycan, and thrombospondin-4 levels were reduced in collagen IX null cartilage, providing the first in vivo evidence for these proteins belonging to the collagen IX interactome. Thrombospondin-4 expression was reduced at the mRNA level, whereas matrilin-4 was verified as a novel collagen IX-binding protein. Furthermore, changes in TGFβ-induced protein βig-h3 and fibronectin abundance were found in the collagen IX knock-out but not associated with COMP ablation, indicating specific involvement in the abnormal collagen IX null cartilage. In addition, the more widespread expression of collagen XII in the collagen IX-deficient cartilage suggests an attempted compensatory response to the absence of collagen IX. Our differential proteomic analysis of cartilage is a novel approach to identify candidate matrix protein interactions in vivo, underpinning further analysis of mutant cartilage lacking other matrix components or harboring disease-causing mutations. PMID:23530037