bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thrombophilic Polymorphisms Are Common in Women with Fetal Loss without Apparent Cause
Authors: Sarig G. , Weiner Z. , Younis J. , Blumenfeld Z. , Lanir N. , Brenner B. 
Published: March 2018

SummaryAn association between fetal loss and thrombophilia has recently been described but has not been yet fully elucidated. We have evaluated prospectively the prevalence of the three common thrombophilic polymorphisms (TP) factor V G1691A (Leiden), thermolabile-methyl-enetetrahydrofolate reductase (TL-MTHFR) C677T and factor II G20210A mutations, in 76 women with fetal loss (≥3 in first, ≥2 in second, ≥1 in third trimester) without apparent cause and 106 controls without fetal loss. Thirty seven out of 76 (49%) of the women in the fetal loss group had at least one TP compared to only 23/106 (22%) in the control group (p = 0.0001). Factor V-Leiden was more common in the fetal loss group 24/76 (32%) compared to the control group 11/106 (10%) (OR = 4.0, 95% CI: 1.8-8.8, p <0.001). Five of the 76 patients (7%) were homozygous for factor V-Leiden compared to none of the controls (p = 0.012). A trend, albeit no statistically significant difference was found between women with fetal loss and control groups regarding factor II G20210A (8% vs. 4% respectively, OR = 2.2, 95% CI: 0.6-8.0, p = 0.23) and MTHFR C677T (18% vs. 10% respectively, OR = 1.95, 95% CI: 0.83-4.6, p = 0.12). Combined TP were documented in 6/76 (8%) patients compared to 1/106 (1%) in controls (OR = 9.0, 95% CI: 1.1-76, p = 0.02). Second or third trimester fetal loss were more common cause of pregnancy termination in 37 patients with TP compared to 39 patients without TP (57/158 (36%) vs. 23/135 (17%) respectively, (p = 0.0004). Thrombophilic polymorphisms are common in women with fetal loss without apparent cause and are associated with late pregnancy wastage. Combinations of TP increase the risk for fetal loss.
Helicobacter Pylori Infection and the Risk of Myocardial Infarction: Role of Fibrinogen and Its Genetic Control
Authors: Zito Francesco , Di Castelnuovo Augusto , D’Orazio Andria , Negrini Riccardo , De Lucia Domenico , Benedetta Donati Maria , Iacoviello Licia 
Published: March 2018

SummaryThe contribution of Helicobacter pylori (HP) infection to the risk of myocardial infarction was evaluated. The role of fibrinogen and its genetic control as a possibile mechanism by which HP may influence myocardial infarction risk was explored in this context. A case-control study was performed in 101 patients with myocardial infarction and in 101 controls.HP infection was associated with an increased risk of myocardial infarction independently for confounding variables (OR 4.1, CI95: 1.8-9.4). HP infection was significantly associated with higher levels of fibrinogen, both in cases and in controls. Furthermore, there was an additive effect of HP infection and B2 allele of BclI fibrinogen poly-morphism in increasing fibrinogen levels. HP infection showed a stronger effect on the risk of myocardial infarction in B2 allele carriers (OR 7.6, CI95: 1.8-31.6) as compared to subjects carrying the B1B1 genotype (OR 3.3, CI95: 1.2-9.2).We showed that a previous HP infection is a risk factor for myocardial infarction. An increase in fibrinogen levels is a possible mechanism by which HP may act. Concomitant conditions, like a genetic predisposition in increasing fibrinogen levels, seem to further increase the effect of HP on myocardial infarction risk.
A Novel Splice Acceptor Site Mutation which Produces Multiple Splicing Abnormalities Resulting in Protein S Deficiency Type I
Authors: Tatewaki Hideki , Iida Hiroko , Nakahara Mutsuko , Tsuda Hiroko , Kinoshita Sachiko , Kanaji Taisuke , Yoshida Nobuyuki , Miyazaki Sumio , Hamasaki Naotaka 
Published: March 2018

SummaryIn an attempt to explore the molecular mechanisms for protein S deficiency, a patient with such a deficiency was examined at the DNA, RNA and protein levels. Nucleotide analyses revealed that the proband, the mother and the grandmother had a G → C substitution in the invariant AG dinucleotide at the splicing acceptor site of intron A/exon 2. This patient was heterozygous for this substitution and the mutant allele was inherited from the proband’s mother and grandmother. Reverse transcription-polymerase chain reaction analysis demonstrated several kinds of splicing abnormalities such as exon skipping and cryptic splicing, in addition to correct splicing. Semiquantitation of mRNA for the protein S gene revealed that the amount of the proband’s mRNA was reduced to 60% of normal. Thus, this mutation impaired the normal processing of mRNA for the protein S gene, resulting in the subject’s severe protein S deficiency.
Regulation of Prothrombinase Activity by Protein S
Authors: Butenas Saulius , Golden Neal , Mann Kenneth , van't Veer Cornelis 
Published: March 2018

SummaryThe independent effect of protein S as prothrombinase inhibitor has been proposed to depend on binding to both coagulation factors Va and factor Xa or on the binding to phospholipid thereby limiting the phospholipid available for prothrombinase activity. In this study we show that plasma concentrations of protein S (300 nM) equilibrated with the prothrombinase components (factor Va, factor Xa, phospholipid) cause a profound inhibition at low phospholipid concentrations (~0.2 μM). This inhibition by protein S of prothrombinase activity is abrogated with increasing phospholipid concentrations. Modeling of the effect of protein S on prothrombinase based only on the reported affinity of protein S for phospholipids (Kd ~ 10-8 M) in an equilibrium model (Clotspeed), predicted the experimentally obtained thrombin generation rates at low phospholipid in the presence of protein S based on the diminished available phospholipid binding sites for the prothrombinase components. Consistently, initial rates of prothrombinase activity are already maximally inhibited when protein S is preincubated with the phospholipid prior to the addition of factor Xa, factor Va and pro-thrombin. The results indicate that the order of addition of prothrombinase components and the availability of phospholipid may have a profound influence on observed effects of protein S on prothrombinase activity. All prothrombinase components (factor Xa, factor Va, phospholipid) become available during the course of the physiological thrombin generation. The effect of protein S was therefore studied on tissue factor-induced, platelet-dependent thrombin generation. Protein S delayed and inhibited the rate of thrombin generation of tissue factor-induced thrombin formation when surface is provided at physiologic concentrations using isolated platelets (2 × 108/ml). In contrast, protein S hardly affected thrombin generation in this model when platelets were pre-activated with collagen. Furthermore, the observed effects of addition of protein C and thrombomodulin in the absence or presence of protein S on tissue factor-induced, platelet-dependent thrombin generation, indicate that protein S and protein C may cooperate in the regulation of prothrombinase activity through independent mechanisms.
The Effects of Unfractionated Heparin on Survival in Patients with Malignancy – A Systematic Review
Authors: Hettiarachchi Rohan , Vink Roel , Büller Harry , Smorenburg Susanne 
Published: March 2018

SummaryClinical and experimental studies have suggested that unfractionated heparin (UFH) effects malignancy progression. We reviewed all published clinical reports concerning the effects of UFH, as compared to no treatment on survival of cancer patients. Studies were classified on methodological strength and subdivided as to whether therapeutic or prophylactic dosages of UFH were used. Mortality rates after 3 years were extracted or calculated. One randomized study that evaluated the use of UFH in therapeutic dosages in patients with small cell lung carcinoma reported on an improved survival (odds ratio (OR) 0.64; 95% confidence interval (CI): 0.25 to 1.62). A detrimental effect was observed in 2 randomized studies which investigated the effects of intraportal UFH treatment in a prophylactic dose after surgery for gastrointestinal cancer (OR 1.66; 95% CI: 1.02 to 2.71). In contrast, level 2 studies in which either therapeutic or prophylactic dosages of UFH on mortality of patients with gastrointestinal cancer were evaluated, showed OR of 0.58 (95% CI; 0.11-3.13) and 0.65 (95% CI 0.51 to 0.84), respectively. We conclude that there is no convincing evidence of either positively or negatively effects of UFH on survival of patients with malignancy.Harry R. Büller is an Established Investigator of the Dutch Heart Foundation
Expression of Tissue Factor and Tissue Factor Pathway Inhibitor in situ in Laryngeal Carcinoma
Authors: Zacharski Leo , Ruciñska Monika , Zimnoch Lech , Jaromin Jacek , Rózañska-Kudelska Malgorzata , Kisiel Walter , Kudryk Bohdan , Wojtukiewicz Marek 
Published: March 2018

SummaryThe blood coagulation mechanism may support tumor progression by several mechanisms including promotion of cell proliferation and angiogenesis. Immunohistochemical procedures were applied to AMeX-fixed sections of twelve cases of squamous cell carcinoma of the larynx obtained at surgical resection to determine the presence and distribution of tissue factor (TF), tissue factor pathway inhibitor (TFPI), other coagulation factors, fibrinogen, and fibrin in situ. TF antigen was present in normal squamous epithelial cells and tumor cells, predominantly in immature tumor cells in the vicinity of the host-tumor interface. Tumor cells stained also for factors VII and X. Staining for TFPI antigen was demonstrated in the connective tissue stroma adjacent to the tumor, in microvascular endothelial cells, and in normal squamous epithelial cells. Fibrinogen and factor XIIIa were distributed throughout the tumor connective tissue stroma. Fibrin (thrombin-cleaved fibrinogen) was detected at the host-tumor interface and along the margins of tumor nodules. Tumor cells in carcinoma of the larynx express a functional, TF-initiated pathway of blood coagulation. Interpretation of these findings together with the results of clinical trials of inhibitors of TF-induced coagulation activation versus effects of inhibitors of TF expression suggest novel approaches to the experimental therapy of laryngeal carcinoma.
Matrix Gla Protein Synthesis and Gamma-carboxylation in the Aortic Vessel Wall and Proliferating Vascular Smooth Muscle Cells
Authors: Cain Dean , Sane David , Wallin Reidar 
Published: March 2018

SummaryMatrix GLA protein (MGP) is an inhibitor of calcification in the arterial wall and its activity is dependent upon vitamin K-dependent γ-carboxylation. This modification is carried out by a warfarin sensitive enzyme system that converts specific Glu residues to γ-carboxyglutamic acid (GLA) residues. Recent studies have demonstrated that the γ-carboxylation system in the arterial wall, in contrast to that in the liver, is unable to use vitamin K as an antidote to warfarin.By use of immunohistochemistry we demonstrate that MGP is expressed in the arterial wall and immunocytochemistry localized the MGP precursors to the endoplasmic reticulum in vascular smooth muscle cells. Resting smooth vascular muscle cells in the aortic wall and proliferating cells from explants of the aorta have all the enzymes needed for γ-carboxylation of MGP. However, when compared to the liver system, expression of the enzymes of the γ-carboxylation system in vascular smooth muscle cells is different. Of particular interest is the finding that the specific activity of the warfarin sensitive enzyme vitamin K epoxide reductase is 3-fold higher in vascular smooth muscle cells than in liver. DT-diaphorase, which catalyses the antidotal pathway for vitamin K reduction in liver, is 100-fold less active in resting vascular smooth muscle cells than in liver. Data obtained from an in vitro γ-carboxylation system suggest that the antidotal pathway catalyzed by DT-diaphorase in the vessel wall is unable to provide the carboxylase with enough reduced vitamin K to trigger γ-carboxylation of MGP. This finding provides an explanation to the inability of vitamin K to work as an antidote to warfarin intoxication of the arterial wall. Therefore the vitamin K dependent γ-carboxylation system in the arterial wall share a common feature with the system in bone cells by being unable to utilize vitamin K as an antidote.
Antithrombin Cambridge II (Ala384Ser): Clinical, Functional and Haplotype Analysis of 18 Families
Authors: Daly M. E. , Tait R. C. , Walker I. D. , Brown K. , Beauchamp N. J. , Preston F. E. , Gyde H. , Harper P. L. , Carrell R. W. , Perry D. J. 
Published: March 2018

SummaryThirty-one individuals from 18 unrelated families with antithrombin deficiency have been identified as having a single point mutation within codon 384 (13268 GCA→TCA) resulting in an alanine to serine substitution. Six families (11 individuals) were identified by the screening of individuals with thromboembolic disease or with a family history of thromboembolic disease, whilst the remaining 12 families (20 individuals) were identified by screening of asymptomatic blood donors. Four individuals had a history of venous thrombotic disease, a further 2 gave a history of superficial thrombophlebitis but the remaining 25 individuals were asymptomatic. Affected individuals demonstrated normal immunological levels of antithrombin but a decrease in anti-IIa activity in the presence of heparin. Haplotype analysis was used to examine the possibility of a founder effect to explain the high frequency of this non-CpG mutation. 29/31 individuals showed a single common “core” haplotype, the only variation existing in the number of copies of an (ATT)n repeat polymorphism – 13, 14, 15 or 17. The results suggest that at most there are four independent origins for this mutation.
The Canine Factor VIII cDNA and 5’ Flanking Sequence
Authors: Cameron Cherie , Notley Colleen , Hoyle Susan , McGlynn Leslie , Hough Christine , Kamisue Seiki , Giles Alan , Lillicrap David 
Published: March 2018

SummaryFactor VIII is a trace plasma glycoprotein involved as a cofactor in the activation of factor X by factor IXa. Inherited deficiency of factor VIII results in the X-linked bleeding disorder hemophilia A which has been documented in humans, horses, sheep and dogs. In this report, the putative proximal promoter, 5’ untranslated region, complete coding sequence and 3’ untranslated region of the canine factor VIII gene have been characterized. When compared to the human gene, the 5’ flanking region shows conservation of transcription factor binding sites in the 5’ untranslated region. Alignment of the amino acid sequence with that of the previously reported human, mouse and pig proteins demonstrates sequence identity of between 77 and 92% for the A1, A2, A3, C1 and C2 domains but an identity of only between 44 and 62% for the central B domain. The three thrombin cleavage sites are conserved in the canine sequence as are the protein C cleavage sites and the von Wille-brand factor binding region. In addition, all six tyrosine residues that are known to undergo sulfation in the human protein are conserved in the dog. The 3’ untranslated region of the canine gene extends 1.5 kilo-bases. The initial 700 basepairs of this sequence are highly GC rich and the sequence terminates with 2 alternative potential polyadenylation sites. The knowledge of this sequence, in combination with a well described canine model of hemophilia A, provides the necessary starting point for studies addressing the long-term evaluation of factor VIII gene therapy using a homologous transgene.
Characterization of Soluble Thrombomodulin Fragments in Human Urine
Authors: Furutani Masayuki , Hiraishi Sayuri , Ishii Hidemi , Nakano Masahiko 
Published: March 2018

SummaryThe soluble thrombomodulin (TM) subspecies in human urine detected by polyclonal anti-human TM IgG were isolated and characterized. 105, 85, 80, 56, 33, 31 and 28 kDa subspecies under reducing conditions was comparable to 78, 66, 56, 200, 52, 30 and 25 kDa under non-reducing conditions, respectively, in the two-dimensional electrophoresis. Each subspecies under non-reducing conditions, except the 200 and 52 kDa molecules, was constituted of single subspecies, whereas the 200 and 52 kDa molecules were constituted of the tetramer of the 56 kDa subspecies of reducing conditions and a dimer of the 33 kDa subspecies, respectively. NH2-terminal amino acid sequences of the 105, 85 and 80 kDa subspecies maintained Ala1-Pro2-Ala3- of intact human TM, however, 56, 33, 31 and 28 kDa subspecies started from Glu137-Gln138-, Gln214-Gly215-, Ser228-Val229- and Ala240-Ile241-, respectively. All subspecies obtained under non-reducing conditions exhibited cofactor activity for thrombin-dependent protein C activation ranging from 58 to 162 pmol APC/min/nmol TM at 0.4 mM Ca2+ indicating that all of the subspecies maintained the fourth to sixth repeat of epidermal growth factor-like structure of intact TM. 85, 80, 56, 33, 31 and 28 kDa subspecies were suggested to lack both chondroitin sulfate glycosaminoglycan (CSGAG), transmembrane and cytoplasmic domains of intact TM, while 105 kDa subspecies lack only CSGAG from the results of kinetic properties and the interaction with phospholipid vesicles composed from phosphatidylcholine and phosphatidylethanolamine.
Effect of SR121566A, a Potent GP IIb-IIIa Antagonist on Platelet-mediated Thrombin Generation In Vitro and In Vivo
Authors: Herault J. P. , Peyrou V. , Savi P. , Bernat A. , Herbert J. M. 
Published: March 2018

SummaryThe effect of SR121566A, a new non-peptide GP IIb-IIIa antagonist was studied in vitro with regard to thrombin generation in platelet rich plasma and in vivo on stasis-induced venous thrombosis in the rabbit. SR121566A inhibited ADP-, arachidonic acid- and collagen-induced human platelet aggregation with IC50 values of 46 ± 7.5, 56 ± 6 and 42 ± 3 nM, respectively. In the same experimental conditions, SR121566A strongly inhibited thrombin generation triggered by low concentrations of tissue factor. SR121566A reduced in a dose-dependent manner both the area under the curve and the thrombin peak concentration but did not affect the lag phase (defined as the time until 10 nM thrombin was generated). Aspirin (100 µg/ml) did not affect thrombin generation.One hour after intravenous administration to rabbits, SR121566A exhibited a potent ex vivo inhibitory effect against ADP-, arachidonic acid- and collagen-induced platelet aggregation. The ID50 were 0.6 ± 0.25, 0.7 ± 0.08 and 0.13 ± 0.08 mg/kg, respectively. The ability of aspirin and SR121566A to affect venous stasis was determined in a stasis-induced venous thrombosis model in rabbits under high and low thrombogenic challenges. While aspirin was ineffective in both conditions, SR121566A significantly inhibited thrombus formation under low thrombogenic challenge demonstrating for the first time that a potent non-peptide platelet GP IIb-IIIa antagonist inhibits thrombin generation in vivo and exhibits a strong antithrombotic effect with regard to stasis-induced venous thrombosis. These results therefore confirm the existence of a close relationship between platelet activation and thrombin generation leading to blood coagulation but also emphasise the key role of platelets in the development of venous thrombosis, most likely through activation of the GP IIb-IIIa complex.
Microvesicles Bind Soluble Fibrinogen, Adhere to Immobilized Fibrinogen and Coaggregate with Platelets
Authors: Solum Nils Olav , Brosstad Frank , Pedersen Turid , Kveine Marit , Holme Pål André 
Published: March 2018

SummaryIn the present study we have investigated whether platelet derived microvesicles can bind soluble fibrinogen, bind to immobilized fibrinogen, and coaggregate with platelets. Flow cytometry was used for studies on binding of soluble fibrinogen and coaggregation, whereas ELISA wells were used to study binding of microvesicles to immobilized fibrinogen. Biotinylated microvesicles produced by stimulation with A23187, thrombin or SFLLRN of platelets which had been surface-labelled with biotin, were used both for the coaggregation experiments and for the binding studies with immobilized fibrinogen. Unlabelled microvesicles and biotinylated fibrinogen were employed when studying binding of soluble fibrinogen to the microvesicles. For the flow cytometry, the biotinylated proteins were reacted with avidin or streptavidin which was PE-conjugated, whereas the same substances were conjugated with alkaline phosphatase for the ELISA studies. The microvesicles formed after stimulation of platelets by SFLLRN or A23187 clearly bound the soluble, biotinylated fibrinogen. Moreover, isolated biotinylated microvesicles added to washed platelets prior to activation, were associated to the microaggregates that formed after stimulation. A significant binding of biotinylated microvesicles to immobilized fibrinogen could also be detected. The binding of micro-vesicles to soluble and immobilized fibrinogen and association to platelets was clearly specific and at least partly dependent on the GPIIb-IIIa complex, as all of these phenomena could be prevented or reduced by addition of the c7E3 Fab which blocks the activated form of this receptor complex. From these in vitro results it is clear that microvesicles can bind to immobilized fibrinogen, bind soluble fibrinogen and are able to coaggregate with platelets. It may be speculated that these results also reflect a haemostatic role of microvesicles in vivo.
International Collaborative Study for the Calibration of a Proposed Reference Preparation for Thromboplastin, Human Recombinant, Plain
Authors: Chantarangkul Veena , Negri Barbara , Clerici Marigrazia , Mannucci Pier Mannuccio , Tripodi Armando 
Published: March 2018

SummaryStocks of the International Reference Preparation (IRP) for thromboplastin, human, plain, coded BCT/253 and held by the World Health Organization (WHO) are nearly exhausted and must be replaced. For practical reasons the choice of the replacement candidate was restricted to two available human recombinant preparations which were coded as X/95 and Y/95 and calibrated in an international collaborative study involving 19 laboratories from Europe, Australia, Canada and Argentina. To minimize the differences between routes of calibration, the two candidates were calibrated against the existing WHO-IRP from human, rabbit and bovine origin and the final ISI was the resultant average value. On the basis of predefined criteria (i.e., within- and between-laboratory precision of the calibration and the conformity to the calibration model), X/95 was the preferred candidate. The assigned ISI (SE of the mean) value is 0.940 (0.0060) and the interlaboratory coefficient of variation 4.7%.