Isolated 3-methylcrotonyl-coenzyme A carboxylase deficiency in a child with metabolic stroke.

We report a 3-year-old boy with isolated 3-methylcrotonyl-coenzyme A deficiency with unexpectedly severe presentation, seizures and history of cerebral ischae-mic episode.

Consanguineous 3-methylcrotonyl-CoA carboxylase deficiency: early-onset necrotizing encephalopathy with lethal outcome.

A patient with a severe neonatal variant of 3-methylcrotonyl-CoA carboxylase (MCC) deficiency is reported. The first child of healthy consanguineous Turkish parents presented on the second day of life with dehydration, cyanosis, no sucking, generalized muscular hypotonia, encephalopathy, respiratory depression requiring mechanic ventilation, macrocephaly, severe acidosis and hypoglycaemia. Elevated C5-OH-carnitine in dried blood spot by tandem MS and elevated urinary excretion of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine suggested MCC deficiency, confirmed by enzyme analysis in cultured fibroblasts. Cerebral ultrasonography and cranial CT findings revealed progressive changes such as disseminated encephalomalacia, cystic changes, ventricular dilatation and cerebral atrophy. Treatment with high-dose biotin and protein-restricted diet was ineffective and the patient died at the age of 33 days with progressive neurological deterioration. Mutation analysis revealed a homozygous mutation in the splice acceptor site of intron 15 in the MCC beta-subunit. Early-onset severe necrotizing encephalopathy should be included in the differential diagnosis of isolated MCC deficiency.

Increased acetylcholine-induced vasodilation in pregnant rats: A role for gap junctional communication.

We have tested the hypothesis that increased gap junctional communication contributes to the augmented endothelium-dependent vasodilation in pregnancy. Contractile force and connexin43 expression were measured in aortic rings from nonpregnant and pregnant rats. Norepinephrine-constricted aortas from pregnant rats were more sensitive to acetylcholine, but not to sodium nitroprusside, compared with those from nonpregnant rats. Vessels from pregnant rats, constricted either with 45 mmol/L KCl or with norepinephrine + 10(-4) mol/L N(G)-monomethyl-L-arginine (L-NMMA), an inhibitor of nitric oxide synthase, also exhibited greater relaxation to acetylcholine. Heptanol, an uncoupler of gap junctional communication, inhibited acetylcholine responses in norepinephrine-constricted aortas from nonpregnant rats but greatly impaired acetylcholine relaxation in aortas from pregnant rats. Heptanol also inhibited in both groups acetylcholine responses in vessels constricted with KCl, only minimally affected acetylcholine relaxation in arteries constricted with norepinephrine + L-NMMA, and did not change sodium nitroprusside-induced relaxation. Tetraethylammonium chloride induced greater contractions in control aortas compared with aortas from pregnant rats. Increased connexin43 mRNA levels were found in the uterus and in the mesenteric, uterine, and thoracic aortic arteries, but not in the heart and brain, from pregnant rats. These results suggest that increased gap junctional communication, possibly due to increased gap junction protein expression, may facilitate the effects of endothelium-derived relaxing factors, contributing to the augmented endothelium-dependent relaxation in arteries from pregnant rats.

Estudo comparativo dos metodos manuais de contagem de celulas sanguineas. / Comparative study of manual methods for blood cell count

Os autores realizaram estudo comparativo de duas metodologias recomendadas para contagem de hemacias e leucocitos, usando diferentes tipos de pipetas (pipeta de Thoma e pipeta de Sahli), para diluicao do sangue. A analise estatistica de 53 amostras mostrou nao haver diferenca significatica entre os dois metodos

Relacao estrutura-atividade em sulfas antibacterianas. / Relationship between structure and activity in antibacterial sulfonamides

A atividade bacteriostatica de derivados sulfalamidicos substituidos em N1, considerando o efeito de dissociacao, foi relacionada com as propriedades fisico-quimicas de suas moleculas, representadas por parametros hidrofobos, eletronicos e estericos, objetivando contribuir para elucidacao do seu mecanismo de acao. A tecnica omega, extensao do metodo aproximado de Huckel, foi utilizada para a determinacao de alguns parametros. Os resultados comprovam a influencia dos efeitos eletronicos dos seus substituintes no mecanismo de acao das sulfas