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. Effects of sleep deprivation on the development of autoimmune disease in an experimental model of systemic lupus erythematosus.

A B S T R A C T This study describes two sensitive, rapid, relatively simple, competitive inhibition radioimmunoassays for detecting immune complex.

We investigated kidney and lung alterations caused by intercellular adhesion molecule type 1 (ICAM-1) blockade after ischemia and reperfusion of hind limb skeletal muscles. Rats were submitted to ligature of the infrarenal aorta for 6 h. The animals were randomized into three groups of 6 rats each: group I, sacrificed after ischemia; group II, reperfusion for 24 h, and group III, reperfusion for 24 h after receiving monoclonal anti-ICAM-1 antibodies. At the end of the experiment, blood samples were collected for creatinine, lactate dehydrogenase, creatine phosphokinase, potassium, pH and leukocyte counts. Samples were taken from the muscles of the hind limbs and from the kidneys and lungs for histological analysis and measurement of the neutrophil infiltrate by myeloperoxidase staining. The groups did not differ significantly with regard to the laboratory tests. There were no major histological alterations in the kidneys. An intense neutrophil infiltrate in the lungs, similar in all groups, was detected. Myeloperoxidase determination showed that after reperfusion there was significantly less retention of polymorphonuclear neutrophils in the muscles (352 ± 70 vs 1451 ± 235 × 10 2 neutrophils/mg; P<0.01) and in the kidneys (526 ± 89 vs 852 ± 73 × 10 2 neutrophils/mg; P<0.01) of the animals that received anti-ICAM-1 before perfusion compared to the group that did not. The use of anti-ICAM-1 antibodies in this experimental model minimized neutrophil influx, thus reducing the inflammatory process, in the muscles and kidneys after ischemia and reperfusion of the hind limbs.

The endothelins (ET-1, 2 and 3) constitute a family of 21 amino acid peptides with potent biological activities. ET-1 is one of the most potent endogenous vasoconstrictors so far identified and its increased concentration in plasma appears to be closely related to the pathogenesis of arterial hypertension as well as to obstructive sleep apnea (OSA). OSA patients exhibit repetitive episodes of apnea and hypopnea that result in hypoxia and consecutive arousals. These patients are chronically sleep deprived, which may aggravate the hypertensive features, since literature data show that sleep deprivation results in hypertension both in humans and in animals. Based on the reported relationship between ET-1, hypertension and sleep deprivation consequences, the purpose of the present study was to determine plasma ET concentrations in paradoxical sleep-deprived animals. Male Wistar rats, 3 to 4 months old (N = 10 per group), were deprived of sleep for 24 and 96 h by the platform technique and plasma ET-1/2 was measured by radioimmunoassay. Analysis of plasma revealed that 96 h of sleep deprivation induced a significant increase in ET-1/2 release (6.58 fmol/ml) compared to control (5.07 fmol/ml). These data show that sleep deprivation altered plasma ET-1/2 concentrations, suggesting that such an increase may participate in the genesis of arterial hypertension and cardiorespiratory changes observed after sleep deprivation.

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We report the finding of unexpected microscopic oval structures in clinical stool samples processed by AFIP/Medicina Laboratorial, a laboratory performing routine clinical analysis in São Paulo, Brazil. Surprisingly, these objects were identified as mite eggs, sometimes accompanied by adult mites. Because misidentification of mite eggs as helminth ova may lead to erroneous treatment with far-reaching consequences, we sought to verify the frequency of adult mites and mite eggs among a number of processed stool specimens. Given their similarity to some helminth eggs, it is important that clinical laboratories recognize these structures, especially in geographic regions where intestinal parasitosis is prevalent.

A monitoração de vários interferentes nos resultados das análises clínicas laboratoriais originados do sistema de transporte de amostras biológicas de um posto de coleta para o local da fase analítica propriamente dita é de extrema importância. Com o objetivo de avaliar a estabilidade dos bioanalitos durante o transporte, os autores, neste trabalho, monitoraram a temperatura das caixas térmicas. Através de dispositivos medidores de temperatura (chips) introduzidos no interior de cada caixa térmica, observou-se que elas permaneceram climatizadas em torno de 13º a 23ºC, simulando a temperatura ambiente por todo o percurso e tempo necessários. Compararam-se os resultados de análises clínicas laboratoriais das amostras biológicas sem transporte realizadas no laboratório de origem da coleta (Jundiaí) com os das mesmas amostras biológicas com transporte realizado na central em São Paulo. Inicialmente foram estudados os principais parâmetros bioquímicos e a coagulação do sangue, além da urinálise com bacteriologia. A análise estatística foi de concordância entre as duas médias através do coeficiente de correlação intraclasse e também pela técnica de Bland-Altman, na qual se observou que, entre os 29 analíticos estudados, 23 (79,3%) apresentaram concordância boa a excelente; cinco (17,2%), moderada a boa; e uma (3,5%), fraca a moderada. Quanto às uroculturas, elas apresentaram 88% de concordância, portanto boa a excelente, e a urina I apresentou 94% de concordância na hematúria e 87,5% na leucocitúria, também boa a excelente. Os dados obtidos pelas correlações dos resultados das amostras e dos gráficos de temperatura emitidos pelos dispositivos registradores representaram indicadores de validação do sistema de transporte e das análises laboratoriais em até 16 horas após coleta do material, simulando um posto muito distante. abstract resumo The results obtained from biological sample analysis may be affected by several factors, among them, the conditions of samples transportation from the site of collection to the central laboratory.The aim of this paper was to verify the stability of the samples submitted to the transportation process (from Jundiaí to São Paulo) by comparing the results of 29 clinical laboratory parameters (including microbiology tests