Fibrinogen aggregation is the last step in blood coagulation. Inhibition of fibrinogen aggregation could lead to anticoagulation effects. However, there is no good method for the ready evaluation of fibrinogen coagulation. A commonly used path method is slow and requires an expensive instrument. In this project, we have developed a microplate reader and In evaluating inhibitors of fibrinogen coagulations there is no good method. As an important process in hemostasis, fibrinogen coagulation is often detected by micro-plate reader. In our test of fibrinogen coagulation, we improved the observing and analyzing method by using photograph to see concentration-depended effect of thrombin inhibitors on the coagulation. Three known thrombin inhibitors, AEBSF, APMSF and PMSF, were applied to develop the method for detecting the fibrinogen coagulation. The results showed our method is of accuracy in determination of the amount of fibrin when compared with other types of methods.

Made available in DSpace on 2014-06-11T19:29:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-15Bitstream added on 2014-06-13T19:59:58Z : No. of bitstreams: 1 muzardo_ga_me_arafcf.pdf: 752970 bytes, checksum: 8e099df2c7034392306fc41fa222b9ad (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O número crescente de casos de intoxicações agudas, acidentais ou suicidas, por organofosforados indica a necessidade de buscar uma estratégia que evite o surgimento de graves efeitos tóxicos irreversíveis da Neuropatia Retardada Induzida por Organofosforados (NRIOP). Esta neuropatia é provocada por alguns destes compostos, como triclorfon, monocrotofós, metamidofós e clorpirifós, que são muito utilizados como agrotóxicos no Brasil e em vários países do mundo. Outro composto neuropático, o tri-orto-cresil fosfato (TOCP), utilizado principalmente como plastificante e fluído hidráulico retardante de chama, é um dos protótipos utilizados para o estudo desta neuropatia em galinhas, que é o animal de escolha para o estudo da NRIOP. Estes compostos organofosforados inibem a atividade da Enzima Susceptível à Neuropatia (ESNp) no cérebro, na medula óssea, nos nervos periféricos e nos linfócitos, iniciando a neurotoxicidade. O TOCP provoca a queda dos níveis de cálcio no plasma e isto causa uma dificuldade de contração do músculo esquelético, levando aos sinais motores da NRIOP. Assim, este projeto propõe uma estratégia de tratamento, com doses de gliconato de cálcio e de fluoreto de fenilmetilsulfonil (PMSF), até 24 horas após a intoxicação pelo TOCP, período em que ocorre a inibição da atividade da ESNp em 70-80%, nível este necessário ao surgimento dos efeitos clínicos da NRIOP. Para a realização dos experimentos, foram utilizados vários grupos de galinhas Isabrown (1,5 a 2,5 Kg; n=4; 18 meses de idade). O primeiro grupo (controle positivo) recebeu apenas 500 mg/kg de TOCP, via oral. Juntamente com a dose de 500 mg/kg de TOCP, os outros grupos receberam, via endovenosa, doses de 5 mg/Kg de gliconato de cálcio e uma dose de 90 mg/Kg de PMSF, via subcutânea, em diferentes tempos. Todas as galinhas... / The growing number of cases of acute intoxication by organophosphorus, either accidental or suicidal, shows the importance of finding a strategy to prevent the irreversible signs of the organophosphorus-induced delayed neuropathy (OPIDN). This neuropathy is caused by components such as triclorphon, monocrotophos, metamidophos and clorpyriphos, widely used as pesticides in Brazil and in many other countries. Another neuropathic compound, the tri-o-cresyl phosphate (TOCP), which is used as a plasticizing component and flame-retardant fluid, is one of the most commonly used chemicals for the study of the neuropathy in chickens, which is the animal of choice for OPIDN research. These compounds inhibit the activity of neurotoxic esterase (NTE) in brain, spinal cord, sciatic nerve and lymphocytes, and they may induce OPIDN. TOCP cause the levels of calcium in the plasma to decrease, which makes it more difficult for the muscles to contract, leading to the motor signs of neurotoxicity. Therefore, this paper suggests a strategy of treatment by providing doses of calcium glyconate and phenylmethylsulfonil fluoride (PMSF), so that diminish the signs of OPIDN, 24 hours before chickens have received TOCP, period within which occurs the largest activity inhibition of NTE, over 70-80%, necessary for observation of the clinical effects of NRIOP. Various groups of Isabrown chicken were studied (1,5 to 2,5 Kg; n=4; 18 months old). The first group (positive control) was given only 500 mg/kg of TOCP, orally. Together with 500 mg/kg of TOCP, the other groups were given intravenous doses of 5 mg/Kg of calcium glyconate and subcutaneous doses of 90 mg/Kg of PMSF, in different times. All hens had their blood tested for calcium, at: 0, 12, 24 and 48 hours; 8, 14 and 28 days after the treatment. The activity of NTE were determined in the lymphocytes... (Complete abstract click electronic access below)