Correlation between the Polymorphism of Coagulation-Related Genes and Lower Extremity Deep Venous Thrombosis / 法医学杂志

Objective To investigate the correlation between the polymorphism of 4 coagulation-related genes, rs1799963 （coagulation factor V gene Leiden）, rs6025 （prothrombin gene G20210A）, rs1042579 （thrombomodulin protein gene c.1418C>T） and rs1801131 （methylenetetrahydroflate reductase gene） and lower extremity deep venous thrombosis （LEDVT）. Methods The 4 genotypes mentioned above of 150 LEDVT patients and 153 healthy controls were detected by the kompetitive allele specific polymerase chain reaction （KASP）, then related blood biochemical indicators were collected, binary Logistic regression was established to screen the independent risk factors of LEDVT, and the correlation between polymorphism of 4 coagulation-related genes and LEDVT and its indicators under different genetic modes after adjusting confounding factors were analyzed. Results Five variables, D-dimer, fibrinogen degradation product, homocysteine, sex and age might be the risk factors of LEDVT. These variables were put into 4 genetic inheritance models, and adjusted in binary Logistic regression. The results suggested that the mutations of rs1042579 were correlated with LEDVT under dominant inheritance mode. Conclusion The gene polymorphism of rs1799963, rs6025 and rs1801131 has no significant correlation with the formation of LEDVT. The gene polymorphism of rs1042579 plays a role under dominant inheritance mode, and might be an independent risk factor for formation of LEDVT.

Cerebral venous thrombosis associated with homozygous factor V Leiden mutation in a 15-year-old girl of Tunisian origin

Cerebral venous thrombosis [CVT] is a rare disease. It has numerous and complex etiologies. Inherited or acquired prothrombotic states play a key role in the development of this disease, such as factor V G1691A mutation [FV Leiden]. A 15-year-old girl presented to the Department of Neurology with a complaint of severe headache with visual blurring. The diagnosis of CVT was not initially suspected because of the patient's condition on presentation. An MRI showed thrombosis in the superior sagittal sinus, confirming venous stroke. Anticardiolipin and antiphospholipid antibodies were assessed. In addition, inherited prothrombotic defects, such as protein C, protein S, and antithrombin deficiencies, and genetic mutations for FV Leiden, prothrombin gene G20210A [Fll G20210A], and methyltetrahydrofolate reductase C677T [MTHFR C677T] were studied. All results were unremarkable except for the unique homozygous FV Leiden mutation, which likely contributed to this prothrombotic situation. This study highlights the fact that FV Leiden may play a significant role in the onset of CVT in young patients

Análise da expressão gênica de proteínas associadas à coagulação sanguínea na neoplasia maligna de esôfago / Analysis of gene expression of proteins associated with blood coagulation in malignant esophageal neoplasm

Estudos recentes indicam que o fator tecidual (TF) participa no crescimento tumoral, metástase e angiogênese através de uma via independente da coagulação sanguínea. A superexpressão do TF em células tumorais contribui para o estado pró-trombótico em pacientes com câncer. Adicionalmente, uma família de receptores acoplados à proteína G, conhecidos como receptores ativados por proteases (PARs), tem sido associada à biologia do tumor. Estes receptores podem ser ativados por proteases da coagulação como a trombina, o fator VIIa (FVIIa) e o fator FXa (FXa), mediando assim a sinalização celular e podendo levar a um aumento da expressão de IL-8 em vários tipos celulares. O objetivo deste estudo foi analisar a expressão do RNAm de TF, PAR-1, PAR-2 e IL-8 em pacientes com câncer de esôfago. Amostras de tecidos foram obtidas de 35 pacientes submetidos a esofagectomia ou endoscopia em 3 hospitais das regiões Sul e Sudeste do Brasil: Hospital Universitário Pedro Ernesto (HUPE-UERJ), na cidade do Rio de Janeiro, Hospital de Clínicas (HCPA-UFRGS), na cidade de Porto Alegre - Rio Grande do Sul e o Hospital de Clínicas - Gastrocentro (HC-UNICAMP), na cidade de Campinas - São Paulo. Amostras de tecido esofágico tumoral e da mucosa normal adjacente ao tumor, foram obtidas de cada paciente e o diagnóstico foi confirmado através da análise histopatológica do tecido adjacente. O RNA total foi então extraído e analisado por transcrição reversa e reação em cadeia da polimerase (RT-PCR) e por PCR em tempo real (qPCR). Nossos resultados demonstraram um aumento significativo, nas amostras tumorais quando comparadas as amostras normais, da expressão de TF (4,2 +- 5,3, SE=0,9), PAR-1 (6,1 +- 4,7, SE=0,9) e IL-8 (18,2 +- 14,4, SE=3,9), o mesmo porém não foi encontrado para o PAR-2 (1,6 +- 0,8, SE=0,2). Nossos dados sugerem que TF, PAR-1 e IL-8 podem ter um importante papel na biologia dos tumores de esôfago. Na busca por esclarecimentos de como as proteínas analisadas...

A number of studies indicate that Tissue Factor (TF) might participate in tumor growth, metastasis and angiogenesis through a pathway that is independet of blood coagulation. TF overexpression by tumor cells contributes to a pro-thrombotic status in cancer patients. Also, a family of G protein-coupled receptors known as protease-activated receptors (PARs) has been implicated in tumor biology. These receptors may be activated by blood coagulation proteases including thrombin, FVIIa and FXa, thus eliciting cell signalling which might lead to interleukin-8 (IL-8) expression by a variety of cells. The aim of this study was to compare the expression of TF, PAR-1, PAR-2 and IL-8 mRNAs in patients with esophageal cancer. Tissue samples were obtained from 35 patients submitted to esophagectomy or endoscopy in three hospitals from south and southeast regions of Brazil: Hospital Universitário Pedro Esnesto (HUPE-UERJ), located at Rio de Janeiro, Hospital de Clínicas (HCPA-UFRGS), located at Porto Alegre, Rio Grande do Sul, and Hospital de Clínicas - Gastrocentro (HC-UNICAMP), located at Campinas, São Paulo. Tumor samples and the corresponding normal mucosa were obtained from each patient and the diagnosis was confirmed by histopathological analysis of adjacent tissues. Total RNA was extracted and further analyzed by reverse transcriptase (RT)-PCR and Real Time PCR. Our results showed a significant increased expression of TF (4,2 +- 5,3, SE=0,9), PAR-1 (6,1 +- 4,7, SE=0,9) and IL-8 (18,2 +- 14,4, SE=3,9) in tumor samples, but not of PAR-2 (1,6 +- 0,8, SE=0,2). Our data indicate that TF, PAR-1 and IL-8 might play an important role in esophageal cancer. To analyze the role of this proteins in oesophageal cancer patients, we used "in vitro" models with TE-1 cell line. Our results demonstrated that TE-1 cells express TF, PAR-1 and PAR-2 and display potent procoagulant activity. In this context, we will further investigate whether the activation of PAR receptors induces...

The role of autolysis loop in determining the specificity of coagulation proteases

We recently demonstrated that the substitution of the autolysis loop (residues 143 to 154 in the chymotrypsin numbering system) of activated protein C (APC) with the corresponding loop of factor Xa (fXa) renders the APC mutant (APC/fX143-154) susceptible to inhibition by antithrombin (AT) in the presence of pentasaccharide. Our recent results further indicated, that in addition to an improvement in the reactivity of APC/fX143-154 with AT, both the amidolytic and anti-factor Va activities of the mutant APC have also been significantly increased. Since the autolysis loop of APC is five residues longer than the autolysis loop of fXa, it could not be ascertained whether this loop in the mutant APC specifically interacts with the activated conformation of AT or if a shorter autolysis loop is responsible for a global improvement in the catalytic activity of the mutant protease. To answer this question, we prepared another APC mutant in which the autolysis loop of the protease was replaced with the corresponding loop of trypsin (APC/Tryp143-154). Unlike an ~500-fold improvement in the reactivity of APC/fX143-154 with AT in the presence of pentasaccharide, the reactivity of APC/Tryp143-154 with the serpin was improved ~10-fold. These results suggest that both the length and structure of residues of the autolysis loop are critical for the specificity of the coagulation protease interaction with AT. Further factor Va inactivation studies with the APC mutants revealed a similar role for the autolysis loop of APC in the interaction with its natural substrate.

Resistência à proteína C ativada / Resistance to activeted protein C

O fator V da coagulaçäo, quando ativado, participa como um co-fator essencial na ativaçäo da pró-trombina pelo fator X ativado. O fator V ativado é inativado pela proteína C ativada, numa reaçäo potencializada pela proteína S. Uma mutaçäo no éxon 10 (Arg 506 Gln) do gene do fator V dß origem a uma molécula do fator V que näo é adequadamente inativada pela proteína C ativada, o que causa a chamada resistência à proteína C ativada.

Técnicas diagnósticas de laboratorio en trombofilias congénitas / Diagnostic laboratory techniques for hereditary trombophillias

Las alteraciones hereditarias de los inhibidores naturales de la coagulación y de los componentes del sistema fibrinolítico, están asociadas con enfermedad tromboembólica. Como no siempre es posible determinar la causa de la trombofilia, se analizan aquí distintas metodologías que pueden ser de utilidad para arrojar más luz sobre este problema; y que están disponibles en la bibliografía, para medir la actividad funcional y la concentración de antitrombina III, proteína C, proteína S, cofactor II de la heparina, glicoproteína rica en histidina, lipoproteína A, fibrinógeno, plasminógeno y homocisteína. En todos los casos es conveniente comenzar primero con la determinación de la actividad funcional de la proteína en estudio y, en caso de encontrar una alteración, se completará el estudio con una cuantificación inmunológica u otra metodología que permita obtener mayor información sobre la alteración

Pseudoquiste óseo en un caso de Hipo-disfibrinogenemia / Osseous pseudocysten in a case of hypodisfibrinogenemia

Se describe un caso de pseudoquiste óseo múltiple de húmero izquierdo, que condujo a fracturas espontáneas en dicho sitio en dos ocasiones, en una niña de 10 años con severa tendencia hemorrágica por Hipo-disfibrinogenemia. Se trata esta de una coagulopatía muy poco frecuente, con una manifestación ósea que hasta ahora hemos observado sólo en pacientes hemofílicos por lo que consideramos de interés describir este caso