Mala absorción de glucosa y de galactosa y su asociación con el síndrome de Down / Malabsorption of glucose and galactose and its relation with Down sydrome

Introducción: La malabsorción de glucosa y de galactosa es una enfermedad genética autosómica recesiva debida a una mutación que afecta al cotransportador de sodio-glucosa. Objetivo: Describir una asociación infrecuente entre el síndrome de Down y la mala absorción de glucosa y de galactosa. Presentación del caso: Niño desnutrido de 3 ½ meses de edad con síndrome de Down, de padres consanguíneos. Presentó precozmente diarrea explosiva, vómitos con deshidratación. Se mejoró tras la eliminación de la alimentación oral y la perfusión hidroelectrolítica y empeoró con la utilización de las sales de rehidratación oral y las fórmulas lácteas, sin proteínas de leche de vaca. El estudio de las heces mostró un pH fecal /5, presencia de glucosa, ionograma de las 24 horas fue: sodio 0,5 mEq (1-10), potasio 2,6 mEq (8-22) y el cálculo realizado para distinguir entre diferentes causas de diarrea dio aumentado: 168 mOsm/kg (50-125). Ante este cuadro clínico se consideró el diagnóstico de malabsorción de glucosa y de galactosa sobre todo tras la mejora de la sintomatología bajo dieta exclusivamente azucarada con fructosa. Conclusiones: Es importante tener en cuenta la malabsorción de glucosa y de galactosa dentro de los diagnósticos diferenciales de las diarreas acuosas congénitas. El diagnóstico precoz y la dieta adecuada con fructosa evitan deshidratación y malnutrición. La particularidad de nuestro caso es la asociación de la malabsorción de glucosa y de galactosa con el síndrome de Down, que, según nuestro conocimiento, es la primera vez que se describe y podría aumentar la morbilidad(AU)

Introduction: Malabsorption of glucose and galactose is a genetic autosomic recesive disease caused by a mutation that affects the co-transportator of sodium-glucose. Objective: To describe an unfrequent relation between the Down syndrome and the malabsortion of glucose and galactose. Case presentation: Undernourished child, 3 and half months old with Down syndrome from parents by blood. He early presented explosive diarrhea and vomiting with dehydration. He improved his state after elimination of oral feeding and a hydroelectrolitic perfusion, and his state worsened with the use of oral rehydration salts and dairy formula, even without cow´s milk proteins. The study of feces showed a fecal pH /5, presence of glucose, and the ionogram after 24 hours showed: sodium 0,5mEg (1-10), potasium 2,6 mEg (8-22) and the calculation made to identify the different causes of diarrhea was increased: 168 mOsm/kg (50-125). Having this clinical records, it was considered a diagnostic of glucose and galactose malabsorption, mainly after the improvement of the symptoms under a diet exclusively sugared with fructose. Conclusions: It is important to take into account glucose and galactose malabsortion in the differential diagnosis of congenital watery diahrrea. The early diagnosis and an adequate diet with fructose avoid dehytration and malnutrition. The particularity of this case is the relation of glucose and galactose malabsorption with Down syndrome, that according to our knowledge is the first time it is described and it can increase the morbility(AU)

Conteúdo de lactose e atividade de beta-galactosidade em iogurtes, queijos e coalhadas produzidos no Brasil / Lactose content and beta-galactosidase activity in yogurts, cheeses and curdled milk made in Brazil

Foram estudados iogurtes e coalhada industrializada em três tempos de estocagem, além de coalhada caseira e síria, e queijos de vários tipos e marcas. Determinou-se o conteúdo de lactose e a atividade de ß-galactosidase destes produtos. Os níveis de lactose foram elevados nos iogurtes e coalhadas, com reduçäo de cerca de 22 por cento com relaçäo ao leite de vaca, apresentando média e desvio padräo de 3,81 ñ 0,46g por cento. Nos queijos, estes níveis foram baixos, variando de 1,91 a 0,03g por cento. A atividade de ß-galactosidase esteve presente nos iogurtes e coalhada, com níveis que variam de 0,58 a 3,6l unidades no tempo I de estocagem, com média e desvio padräo de 2,15 ñ 0,23 U. Houve queda significativa desta atividade segundo o tempo de estocagem. Analisando os achados e comparando com os estudos de literatura conclui-se que os produtos estudados, quer pelo seu baixo conteúdo de lactose (queijos e yakult), quer pela presença ß-galactosidase (iogurtes e coalhadas no tempo I), provavelmente seriam tolerados pela maioria dos indivíduos hipolactásicos

Lectin binding to complex carbohydrate at the interface: a study by resonance energy transfer.

The binding affinity of the oligosaccharide moiety of a neutral glycosphingolipid, asialoGM1, towards Ricinus communis agglutinin (RCAI) was determined for the first time by fluorescence resonance energy transfer (RET). The asialoGM1 was incorporated into a phospholipid (DMPC) vesicle doped with dansylated DPPE and then titrated with an increasing amount of the galactose specific RCAI. The efficiency of RET was determined by a saturable increase in the quenching of 'donor' fluorescence, i.e. the 'trp' residue of RCAI, due to the energy transfer from the 'acceptor' dansyl group on the surface of the vesicle. The apparent binding constant was found to be in the range of 10(5)-10(6) M-1 at 27 degrees C.