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- ItemSomente MetadadadosBlood coagulation and fibrinolytic factors in 105 patients with hemorrhagic syndrome caused by accidental contact with Lonomia obliqua caterpillar in Santa Catarina, Southern Brazil(Schattauer Gmbh-verlag Medizin Naturwissenschaften, 2003-02-01) Zannin, Marlene; Lourenco, Dayse Maria [UNIFESP]; Motta, Guacyara [UNIFESP]; Dalla Costa, Luís R.; Grando, Maargareth; Gamborgi, Geni P.; Noguti, Maria A. [UNIFESP]; Chudzinski-Tavassi, Ana M.; Inst Butantan; Universidade Federal de Santa Catarina (UFSC); Universidade Federal de São Paulo (UNIFESP); Chapeco Blood Ctr Santa Catarina; CIT SCHaemostatic disorders caused by Lonomia obliqua caterpillars has reached epidemic proportions in southern Brazil. Here we evaluated coagulation and fibrinolysis in 105 patients after accidental contact with Lonomia obliqua caterpillars. Global coagulation tests were prolonged in most cases and patients were divided into 3 groups according to fibrinogen (Fg) level: less than or equal to0.5 g/l (group A); 0.51-1.5 g/l (group B), >1.5 g/l (group C). There was a significant reduction of factors V, XIII, VIII and prekallikrein in group A, with no change in factors X, II and von Willebrand factor. Thrombin-antithrombin and prothrombin F1+2 were elevated in most patients. Antithrombin and protein S were not changed whereas protein C levels were reduced in group A. Plasminogen and alfa2-antiplasmin levels were significantly reduced in group A and D-Dimer levels were extremely high in all groups, showing that fibrinolysis had been activated, possibly secondary to fibrin production. Levels of t-PA were normal and PAI-1 was mildly elevated in group A. The. platelet count remained above 150 X 10(9) platelets/ml in 97% of cases. In summary, our results suggest that Lonomia obliqua envenoming is characterized by a consumption coagulopathy and secondary fibrinolysis.
- ItemSomente MetadadadosCytokine gene variants and venous thrombotic risk in the BRATROS (BRAZILIAN THROMBOSIS STUDY)(Elsevier B.V., 2007-01-01) Pieroni, Fabiano; Lourenco, Dayse M.; Morelli, Vania M.; Maffei, Francisco H.; Zago, Marco A.; Franco, Rendrik F.; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP); State Univ Sao Paolo; Fleury Res InstIntroduction: Venous thrombosis (VT) and inflammation are two closely related entities. in the present investigation we assessed whether there is a relation between genetic modifiers of the inflammatory response and the risk of VT.Materials and methods: 420 consecutive and unrelated patients with an objective diagnosis of deep VT and 420 matched controls were investigated. the frequencies of the following gene polymorphisms were determined in all subjects: TNF-alpha-308 G/A, LT-alpha+252 A/G, IL-6-174 G/C, IL1-ra 86 bp VNTR, IL-10-1082 A/G and CD-31 125 C/G.Results: Overall odds ratio (OR) for VT related to TNF-alpha-308 G/A, LT-alpha+252 A/G, IL-6-174 G/C, Al allele (4 bp repeat) of the IL1 -ra 86 bp VNTR, IL-10-1082 A/G and CD-31 125 C/G were respectively: 1.0 (CI95: 0.8-1.5), 1.3 (095: 1.0-1.7), 1.1 (CI95: 0.9-1.5), 1.6 (CI95: 1-2.5), 1.2 (CI95: 0.8-1.7) and 0.8 (CI95: 0.6-1.1). A possible interaction between polymorphisms was observed only for the co-inheritance of the mutant alleles of the LT-alpha+252 A/G and IL-10-1082 G/A polymorphisms (OR=2; CI95: 1.1-3.8). the risk of VT conferred by factor V Leiden and FII G20210A was not substantially altered by co-inheritance with any of the cytokine gene polymorphisms.Conclusions: Cytokine gene polymorphisms here investigated did not significantly influence venous thrombotic risk. (C) 2006 Elsevier B.V. All rights reserved.
- ItemAcesso aberto (Open Access)Evaluation of the changes on hemostatic parameters induced by valdecoxib in male Wistar rats(Associação Brasileira de Hematologia e Hemoterapia e Terapia Celular, 2006-03-01) Fronza, Marcio; Wrasse, Micheli; Brum Junior, Liberato; Sangoi, Maximiliano S.; Dalmora, Sérgio L. [UNIFESP]; Industrial Pharmacy; Universidade Federal de São Paulo (UNIFESP)The effects of the cyclooxygenase (COX)-2 selective inhibitor, valdecoxib, on blood coagulation parameters were evaluated, along with aspirin in male Wistar rats. Groups of animals were administered a daily oral dose of 10 mg/kg rat of valdecoxib, 100 mg/kg rat of aspirin and the vehicle alone during 4 weeks. Blood samples were collected at the end of 1, 2, 3 and 4 weeks of administration period and the plasma concentrations of valdecoxib were determined by RP-HPLC giving mean values of 101.1, 113.5, 164.0 and 184.6 ng/mL, respectively. The same plasma samples were used for the analysis of hematological parameters and the results compared to the controls. Valdecoxib induced significant activated partial thromboplastin time reduction (18%) after 2 weeks and prothrombin time reduction (12.2%) after 3 weeks (P<0.05). There were no significant changes in the platelet count and fibrinogen levels. The anti-factor Xa and anti-factor IIa activities showed slight reductions, but only significant for the anti-factor Xa on the 3rd week (6.7%). The results showed that valdecoxib at the dose tested with the plasmatic concentrations induced some changes in the hemostatic function of rats, which can be helpful to understand the side effects and the safe use of the drug.
- ItemSomente MetadadadosInsularinase A, a prothrombin activator from Bothrops insularis venom, is a metalloprotease derived from a gene encoding protease and disintegrin domains(Walter de Gruyter Gmbh, 2005-06-01) Modesto, JCD; Junqueira-de-Azevedo, ILM; Neves-Ferreira, AGC; Fritzen, M.; Oliva, MLV; Ho, P. L.; Perales, J.; Chudzinski-Tavassi, A. M.; Inst Butantan; Inst Burantan; Fiocruz MS; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)The first low-molecular-mass metalloprotease presenting prothrombin activating activity was purified from Bothrops insularis venom and named insularinase A. It is a single-chain protease with a molecular mass of 22 639 Da. cDNA sequence analysis revealed that the disintegrin domain of the precursor protein is post-translationally processed, producing the mature insularinase A. Analysis of its deduced amino acid sequence showed a high similarity with several fibrin(ogen)olytic metalloproteases and only a moderate similarity with prothrombin activators. However, SIDS-PAGE of prothrombin after activation by insularinase A showed fragment patterns similar to those generated by group A prothrombin activators, which convert prothrombin into meizothrombin independently of the prothrombinase complex. in addition, insularinase A activates factor X and hydrolyses fibrinogen and fibrin. Chelating agents fully inhibit all insularinase A activities. Insularinase A induced neither detachment nor apoptosis of human endothelial cells and was also not able to trigger an endothelial proinflammatory cell response. Nitric oxide and prostacyclin levels released by endothelial cells were significantly increased after treatment with insularinase A. Our results show that, although its primary structure is related to class P-I fibrin(ogen)olytic metalloproteases, insularinase A is functionally similar to group A prothrombin activators.
- ItemAcesso aberto (Open Access)Iron stores and coagulation parameters in patients with hypoxemic polycythemia secondary to chronic obstructive pulmonary disease: the effect of phlebotomies(Associação Paulista de Medicina - APM, 1997-04-01) Martinez, José Antônio Baddini [UNIFESP]; Guerra, Celso Carlos de Campos [UNIFESP]; Nery, Luiz Eduardo [UNIFESP]; Jardim, José Roberto [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)This study was designed to determine the effects of phlebotomy on iron body contents and coagulation tests of COPD patients with polycythemia secondary to hypoxemia. Seventeen patients with COPD and hematocrits higher than 54 percent (mean Hct: 57 ± 0.49 percent ), who had not received anti-inflammatory or antiplatelet aggregation agents recently. Their mean forced expiratory volume at 1 second (FEV1) was 0.92 ± 0.11 L. Intervention: Blood work was collected to evaluate the following: serum iron and ferritin levels, total iron binding capacity, transferrin saturation index, fibrinogen plasma levels, activated partial thromboplastin time, platelet count, platelet aggregation measurements, and thromboelastography coagulation parameters. The blood samples were obtained before and about 7 days after the hematocrit correction by 300-400 ml phlebotomies done every other day. The mean number of phlebotomies done for each patient was 4.4. Postphlebotomy iron serum levels decreased from 90.1 ± 14.8 to 59.7 ± 9.9 mg/dl and the ferritin serum levels from 133.8 ± 37.9 to 70.8 ± 32.7 ng/ml (p< 0.05). Regarding the coagulation studies, there were significant increases in the platelet count, from 227,300 ± 13,900 to 312,500 ± 30,200 per mm³, and in the maximum clot amplitude (a) obtained by thromboelastography ( from 53.6 ± 1.4 percent to 60.4 ± 1.1 percent). The coagulation time (k) of the thromboelastography also decreased significantly, from 7.5 ± 0.7mm prephlebotomy to 4.5 ± 0.3mm postphlebotomy. Although the coagulation changes were small amount, the observed significant decrease in iron contents may have important clinical implications.
- ItemSomente MetadadadosNitridergic platelet pathway activation by hementerin, a metalloprotease from the leech Haementeria depressa(Walter de Gruyter & Co, 2003-09-01) Chudzinski-Tavassi, A. M.; Bermejo, E.; Rosenstein, R. E.; Faria, F.; Sarmiento, MIK; Alberto, F.; Sampaio, M. U.; Lazzari, M. A.; Inst Butantan; Acad Nacl Med Buenos Aires; Univ Buenos Aires; Universidade Federal de São Paulo (UNIFESP)Hementerin (HT) is an 80 kDa fibrino(geno)lytic metalloprotease, purified from saliva of the leech Haementeria depressa. in the present report, the effect of HT on several functional parameters of human platelets was assessed. HT inhibited platelet aggregation and ATP release induced by different agonists such as ADP, adrenaline, collagen, thrombin, and arachidonic acid. HT did neither modify the expression of platelet glycoproteins (Ib, IIbIIIa, IaIIa, IV) nor intraplatelet fibrinogen levels, whereas it markedly decreased CD62P and CD63 levels after the stimulation with thrombin. HT significantly increased thrombininduced platelet Ca2+ intracellular levels, cGMP content and nitric oxide synthase (NOS) activity. the effect of HT on platelet aggregation was reversed by two NOS inhibitors, N-omega-Nitro-L-arginine methyl ester and 2 N-G-Nitro-L-arginine. in summary, these results indicate that HT is an effective inhibitor of human platelet aggregation, presumably through activation of the platelets nitridergic pathway.
- ItemSomente MetadadadosPlasma proteins of hemostasis in the hepatointestinal form of schistosomiasis mansoni(Lippincott-raven Publ, 1996-09-01) CamachoLobato, L.; Borges, D. R.; Universidade Federal de São Paulo (UNIFESP)The hepatosplenic form of schistosomiasis mansoni is associated with impairment of blood coagulation, a result of reduced synthesis of clotting factors and inhibitors, enhanced fibrinolytic activity, or ''consumption'' of plasma clotting proteins. the pathogenesis of the latter mechanism has not been elucidated. Schistosoma mansoni (Sm) has a long lifespan as an intravascular fluke, probably a consequence of its ability to evade host immunologic defense mechanisms. in order to determine if the parasite is able to disturb hemostasis in vivo, we studied 21 non-alcoholics with normal body mass index, and HBsAg, anti-HBc, and anti-HCV negative adult males, who were not using drugs. Eleven had the hepatointestinal form of the disease, with viable Sm ova in stools, and 10 were healthy volunteers (control group). Blood specimens were drawn by a two-syringe technique for both the performance of liver tests and determination of hemostasis proteins (prothrombin, antithrombin III, protein C, protein S, high-molecular-weight kininogen, and plasminogen). the latter proteins were assayed immunologically in plasma using specific antibodies. Statistical analysis of the results failed to demonstrate any significant difference between the two groups. We may therefore conclude that there is no derangement of hepatic protein synthesis in the mild form of the disease and that Sm probably escapes host defense mechanisms in vivo, and does not contribute to the consumption coagulopathy described in the hepatosplenic form of the disease.
- ItemAcesso aberto (Open Access)Proteinase inhibitors in Brazilian leguminosae(Instituto Oswaldo Cruz, Ministério da Saúde, 1991-01-01) Sampaio, Claudio Augusto Machado [UNIFESP]; Oliva, Maria Luiza Vilela [UNIFESP]; Tanaka, Aparecida Sadae [UNIFESP]; Sampaio, Misako Uemura [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); UFMS Instituto de Química Departamento de QuímicaSerine proteinase inhitors, in the seeds of several Leguminosae from the Pantanal region (West Brazil), were studied using bovine trypsin, a digestive enzyme, Factor XIIa and human plasma Kallikrein, two blood clotting factors. The inhibitors were purified from Enterolobium contortisiliquum (Mr=23,000), Torresea cearensis (Mr = 13,000), Bauhinia pentandra (Mr = 20,000) and Bauhinia bauhinioides (Mr = 20,000). E. contortisiliquum inhibitor inactivates all three enzymes, whereas the T. cearensis inhibitor inactivates trypsin and Factor XSSa, but does nor affect plasma kallikrein; both Bauhinia inhibitors, on the other hand, inactivate trypsin and plasma kallikrein but only the Bpentandra inhibitor affects Factor XIIa. Ki values were calculated between 10 [raised to the power of] -7 and 10 [raised to the power of] -8 M.
- ItemSomente MetadadadosA prothrombin activator from Bothrops erythromelas (jararaca-da-seca) snake venom: characterization and molecular cloning(Portland Press, 2003-01-01) Silva, Márcia B.; Schattner, Mirta; Ramos, Celso RR; Junqueira-de-Azevedo, Inácio LM; Guarnieri, Míriam C.; Lazzari, Maria A.; Sampaio, Claudio Augusto Machado [UNIFESP]; Pozner, Roberto G.; Ventura, Janaína S.; Ho, Paulo L.; Chudzinski-Tavassi, Ana M.; Inst Butantan; Universidade Federal de Pernambuco (UFPE); Consejo Nacl Invest Cient & Tecn; Universidade Federal de São Paulo (UNIFESP)A novel prothrombin activator enzyme, which we have named 'berythractivase', was isolated from Bothrops erythromelas (jararaca-da-seca) snake venom. Berythractivase was purified by a single cation-exchange-chromatography step on a Resource S (Amersham Biosciences) column. the overall purification (31-fold) indicates that berythractivase comprises about 5% of the crude venom. It is a single-chain protein with a molecular mass of 78 kDa. SDS/PAGE of prothrombin after activation by berythractivase showed fragment patterns similar to those generated by group A prothrombin activators, which convert prothrombin into meizothrombin, independent of the prothrombinase complex. Chelating agents, such as EDTA and o-phenanthroline, rapidly inhibited the enzymic activity of berythractivase, like a typical metalloproteinase. Human fibrinogen Aalpha-chain was slowly digested only. after longer incubation with berythractivase, and no effect on the beta- or gamma-chains was observed. Berythractivase was also capable of triggering endothelial proinflammatory and procoagulant cell responses. von Willebrand factor-was released, and the surface expression of both intracellular adhesion molecule-1 and E-selectin was up-regulated by berythractivase in cultured human umbilical-vein endothelial cells. the complete berythractivase cDNA was cloned from a B. erythromelas venom-gland cDNA library. the cDNA sequence possesses 2330 bp and encodes a preproprotein with significant sequence similarity to many other mature metalloproteinases reported from snake venoms. Berythractivase contains metalloproteinase, desintegrin-like and cysteine-rich domains. However, berythractivase did not elicit any haemorrhagic response. These results show that, although the primary structure of berythractivase is related to that of snake-venom haemorrhagic metalloproteinases and functionally similar to group A prothrombin activators, it is a prothrombin activator devoid of haemorrhagic activity. This is a feature not observed for most of the snake venom metalloproteinases, including the group A prothrombin activators.
- ItemSomente MetadadadosThe role of hemocytes in the immunity of the spider Acanthoscurria gomesiana(Elsevier B.V., 2008-01-01) Fukuzawa, Aline H.; Vellutini, Bruno C.; Lorenzini, Daniel M.; Silva, Pedro I.; Mortara, Renato A. [UNIFESP]; Silva, Jose M. C. da; Daffre, Sirlei; Universidade de São Paulo (USP); Inst Butantan; Universidade Federal de São Paulo (UNIFESP)Invertebrates protect themselves against microbial infection through cellular and humoral immune defenses. Since the available information on the immune system of spiders is scarce, the main goat of the present study was to investigate the role of hemocytes and antimicrobial peptides (AMPs) in defense against microbes of spider Acanthoscurria gomesiana. We previously described the purification and characterization of two AMPs from the hemocytes of naive spider A. gomesiana, gomesin and acanthoscurrin. Here we show that 57% of the hemocytes store both gomesin and acanthoscurrin, either in the same or in different granules. Progomesin labeling in hemocyte granules indicates that gomesin is addressed to those organelles as a propeptide. in vivo and in vitro experiments showed that lipopolysaccharide (LPS) and yeast caused the hemocytes to migrate. Once they have reached the infection site, hemocytes may secrete coagulation cascade components and AMPs to cell-free hemolymph. Furthermore, our results suggest that phagocytosis is not the major defense mechanism activated after microbial challenge. Therefore, the main reactions involved in the spider immune defense might be coagulation and AMP secretion. (C) 2007 Elsevier B.V. All rights reserved.