Influência do grau de comprometimento hepático sobre a circulaçäo e excreçäo renal do ácido úrico, em pacientes cirróticos / Influence of the degreees of chronic hepatic failure on the circulation and renal excretion of uric acid in cirrhotic patients

A influência do grau de insuficiência hepatocelular (na cirrose hepática) sobre a circulaçäo e excreçäo do ácido úrico foi investigada em 12 pacientes cirróticos, de etiologia alcoólica, classificados em Child A (n=5) e Child B+C (n=7), todos do sexo masculino de 27 a 59 anos de idade, comparativamente ao grupo controle saudável (n=5), pareado por sexo e idade. A excreçäo urinária do ácido úrico e dos demais metabólitos nitrogenados (uréia, amônia e creatinina) foi estudada nas condiçöes de dieta hipoprotéica-hipoenergética (0,4g-20kcal/kg/d) e normoprotéica-normoenergética (1,14g-38kcal/kg/d). Os níveis séricos de ácido úrico, de albumina e alfa-1 antitripsina (alfa 1AT) foram determinados em amostras de sangue obtidas após jejum. A presença da doença hepática resultou na elevaçäo dos níveis de alfa 1AT, e o agravamento hepatocelular, na queda de albuminemia, sem alteraçäo significativa do ácido úrico circulante. A excreçäo urinária do ácido úrico foi semelhante entre os grupos, em ambas as dietas, porém, na dieta hipoprotéica-hipoenergética, o ácido úrico näo acompanhou o padräo de excreçäo da uréia e da creatinina, o que pode ser atribuído às quedas da ureogênese e da massa muscular (creatinogênese), com o agravamento da doença ou a maior capacidade renal em reter ácido úrico, nestas condiçöes. Isto pode ser configurado matematicamente, relacionando-se metabólitos excretados na urina com seus níveis plasmáticos, mostrando hipoexcreçäo de 45 por cento dos hepatopatas, tanto para o ácido úrico como para a creatinina. Assim, a menor produçäo hepática do ácido úrico, pelos pacientes cirróticos, seria compensada pela menor excreçäo renal do metabólito, preservando os níveis plasmáticos. A importância fisiológica deste processo adaptativo estaria fundamentada na participaçäo do estresse oxidativo, na gênese e perpetuaçäo da cirrose pelo álcool, e nas propriedades anti-oxidantes do ácido úrico.

Estudo dos fios de poligliconato, categute cromado e poliglactina 910 em contato com urina estéril, urina contaminada por Escherichia coli e Proteus mirabilis com variaçöes da concentraçäo de amônia urinária: estudo experimental em ratas Wistar / Polyglyconate, chromic catgut and polyglactin 910 strands in contact with sterile urine, urine infected by Escherichia coli and Proteus mirabilis with variations of the urinary ammonia concentration: experimental study in Wistar female rats

Com o objetivo de avaliar o comportamento dos fios de sutura absorvíveis em contato com urina estéril, urina contaminada por Escherichia coli e por Proteus mirabilis, foram utilizadas 90 ratas Wistar, distribuídas em três grupos de 30 animais cada, e também três tipos de fios de sutura absorvíveis (poligliconato, categute cromado e poliglactina 910). A alta concentraçäo de amônia na urina infectada por Proteus mirabilis alterou a resistência tênsil dos fios absorvíveis sintéticos. Existiu também uma relaçäo direta entre a distribuiçäo dos fios de poliglactina 910 e a quantidade de amônia na urina

Urinary aspartate transaminase (AST) activity and detection of its inhibitors in normal urine.

Urinary aspartate-transaminase activity in the whole urine was found to be mean +/- S.D. = 8.46 +/- 0.69 l.U/l when measured immediately after urine collection. About 50% loss in enzyme activity was observed after 18 hours dialysis. An overall 176% increase in enzyme activity followed by Sephadex G-25 (fine) whole urine fractionation and a highly significant (P less than .001) partial inhibition by earlier Sephadex fractions and maximum inhibition by earlier Sephadex fractions and maximum inhibition of enzyme by fraction 7 have suggested the presence of both high and low molecular weight urinary inhibitors of aspartate-transaminase. Urea and ammonia presence and inhibitor activity in fraction 6 to 8 bear a close parallelism; both the substances produced 31% inhibition of partially purified goat liver GOT at concentrations approximating normal human urine. Therefore, low enzyme activity and its substantial loss in the whole urine and during dialysis may be due to the concomitant inhibitory effects of urea, ammonia and unidentified nature of high molecular weight substance(s). The present method may be effective in separating inhibitors and overcoming the disadvantages of dialysis in determining true urinary aspartate-transaminase activity.

Nitrogen and sulphur elimination in 24 hours urine by elderly Indians.

Urinary output of N2-urea, creatinine, uric acid, ammonia and organic and inorganic SO3 were repeatedly examined in healthy vegetarian subjects in Bombay--35 elderly and 2 young. Their routine diet examined for a week indicated an average intake of 56 g proteins (15 g animal) and excretion of about 8 g N2, 0.75 g of SO3 both in young and old subjects. These are much lower than figures reported for Europeans taking protein rich diets. Two elderly subjects supplemented their protein intake to 95 g/day (50 g animal) for 3 weeks. A progressive rise in the outputs of N2 and SO3 with increasing protein intakes was seen. SO3 estimation like that of N2 (urea) is indicative of the protein consumption of a person, but the estimations of urea output per day being easier are to be preferred.

Further Analysis of Various Renal Functions in the Korean III. Urinary Excretion of Phosphate, Ammonia and Titratable Acid

In an attempt to investigate the pattern of the urinary acidification process in the Korean, the urinary excretion of phosphate, ammonia, and the titratable acid were measured in 20 medical students (A group) and in 15 psychiatric patients (B group) under regular Korean diets, while the effects of high protein diets on them were studied in 4 subjects. In addition, TmPO4 was also determined in 11 subjects. The urinary excretions of phosphate, titratable acid, and ammonia under regular Korean diets were markedly lower as compared to those of the Europeans. However, there was no difference in the plasma concentration of phosphate between the Korean and the European. Upon administration of high protein diets, the urinary excretions of phosphate and titratable acid increased while the urine pH and the ammonia excretion were little affected. Thus, the correlations between urinary nitrogen and titratable acidity were 0.50 and 0.65, respective1y, showing a linear relationship. However, the correlation between urinary nitrogen and ammonia excretion was slight. The value of TmPO4 ranged from 74 to 355 muM/min with the mean of 193 muM/min, which is considerably higher than that of the European. On the basis of these findings, the overall pattern of the urinary acidification processes in the Korean is discussed.