Evaluation of the blood coagulation mechanism and platelet aggregation in individuals with mechanical or biological heart prostheses.

Oral anticoagulants have been widely employed to decrease thrombotic risk by reducing the levels of vitamin K-dependent clotting factors. Paradoxically, the use of oral anticoagulants also decreases the levels of natural anticoagulants (protein C and protein S), which favors the hypercoagulability state. Increased platelet activation has been reported in patients undergoing warfarin treatment. These findings have raised questions about the antagonistic effect of oral anticoagulants and their implications for hemostatic balance. The aim of this study is to determine the relationship between warfarin dosage and prothrombin time [International Normalized Ratio (INR)], platelet aggregation, vitamin K-dependent clotting factors, and protein C and protein S. Blood samples from 27 patients were analyzed, seven with mechanical prostheses and 20 with biological prostheses, and 27 controls. Multiple regression analysis showed that factor II most significantly determines the INR. Results showed that the INR, clotting factors, and protein C and protein S activity did not correlate with warfarin dosage, highlighting the need for accurate laboratory monitoring of those undergoing anticoagulant therapy.

[Diagnosis wi transesophageal echocardiography and clinical course of 35 patients with flail mitral valve]. / Diagnóstico pela ecocardiografia transesofágica e evolução de 35 pacientes portadores de flail mitral valve.

PURPOSE: To describe transesophageal echocardiographic findings in patients presenting with flail mitral valve and to obtain their clinical follow-up. METHODS: From January/93 to March/97, 1675 patients were submitted to transesophageal echocardiogram at our institution; 35 of them were diagnosed as having flail mitral valve and their clinical follow-up was obtained. RESULTS: Thirty-five patients with the diagnosis of flail mitral valve were studied. Mean age was 65 +/- 15 years (12-87) and 27 (77%) were male. The posterior leaflet was involved in 25 (71%) patients. Ruptured chrodae tendineae was present in all but one patient in whom flail mitral valve was due to a very elongated and redundant chordae. The etiology was prolapse and/or mixomatous degeneration in 16 patients, degenerative in 10, ischemic in 5, rheumatic in 4 and endocarditis in 3. Mitral regurgitation was severe in 25 (71%) patients and moderate in 10 (29%). The mean follow-up was 375 +/- 395 days (1 to 1380). Nineteen patients were followed clinically and 16 were submitted to surgery (transesophageal echocardiogram findings were confirmed in all 16). Overall mortality was high (34%). Among the survivors, 17 are in NYHA class I and 6 in class II. CONCLUSION: The diagnosis of flail mitral valve by transesophageal echocardiography is accurate, allowing for the definition of its mechanism and etiology, as well as the evaluation of hemodynamic compromise. The observed high mortality at the time of diagnosis may be related to the severity of the disease causing the flail mitral valve. Although non-operated survivors are doing well, the observed low functional class in these patients may be related to the short period of follow-up.

Determination of lipids, including medium-chain fatty acids, in human feces.

In this method for determining fecal lipids, feces are saponified with ethanolic potassium hydroxide, the ethanol is evaporated, and the acidified residue extracted with hexane. An aliquot of the hexane solution is then titrated with ethanolic sodium hydroxide, the solvents are evaporated, and the residue (soaps and unsaponifiable matter) is weighed. The unsaponifiable matter is extracted with acetone and determined gravimetrically. The method thus permits the determination of milli-equivalents of fatty acids, total lipids, and fatty acids in one sample and is applicable to feces containing medium-chain fatty acids and their triglycerides.

Presença de Campylobacter spp. em macacos-de-cheiro (Saimiri spp.) assintomáticos cativos e sua correlação com as condições de manejo / Campylobacter spp. in asymptomatic captive squirrel monkeys (Saimiri spp.) and its correlation with the handling conditions

Avaliou-se a circulação de Campylobacter spp. em uma criação de primatas neotropicais macacos-de-cheiro (Saimiri spp.), clinicamente saudáveis, utilizados em investigações biomédicas. A análise foi feita no decorrer de sete anos não consecutivos, de 1995 a 1999, 2002 e 2003. Os resultados revelaram um maior índice de positividade no ano de 1996, em contraste com a ausência do agente em 2003. Os dados sugerem que as alterações realizadas no manejo animal, ao longo deste estudo, foram eficazes para a eliminação do Campylobacter spp. na criação de macacos-de-cheiro, levando os animais a uma melhor qualidade de vida e, consequentemente, obtendo-se um melhor produto para fins de pesquisas.

The circulation of Campylobacter spp. in a breeding colony of clinically healthy neotropical primates squirrel monkeys (Saimiri spp.) used in biomedical investigation was evaluated. Analyses were undertaken during seven non-consecutive years: 1995 to 1999, 2002 and 2003. Results revealed a higher rate of positivity in 1996, in contrast to the absence of the agent in 2003. The data suggest that the changes made in the animal management during this study were effective for the Campylobacter spp. elimination of the squirrel monkeys breeding colony, leading to a better quality of life and, hence, resulting in a better animal for research.