Lactase and placebo in the management of the irritable bowel syndrome: a double-blind, cross-over study.

A double-blind, cross-over, therapeutic, clinical trial of the efficacy of exogenous, microbial beta-D-galactosidase to reduce the symptoms of the irritable bowel syndrome (IBS) was conducted in 12 patients whose customary diets regularly included milk. Eight of the 12 subjects (67%) proved to be lactase-nonpersistent, lactose-maldigesters when challenged with a aqueous dose of 12.5 g. The study lasted 4 months, with the first month a non-intervention, control period and the latter 3 months alternating in the sequence, treatment/placebo/treatment, or placebo/treatment/placebo. When symptoms during trial months were analyzed by the cumulative sum procedure, gastrointestinal symptoms were found to be independent of lactase treatment. We found a positive temporal association of the severity of both gastrointestinal and non-gastrointestinal symptomatology. In populations with a high prevalence of lactose deficiency, IBS symptoms appear to be independent of lactose maldigestion.

Lack of relationship between lactose absorption and senile cataracts.

In a double-blind study using the hydrogen breath-excretion test to identify lactase status, we found 45% of absorbers in a group of 64 patients with senile cataracts compared with 71% of absorbers in the control group. These results oppose the hypothesis that lactose absorbers are especially prone to develop senile cataracts.

Gene frequencies and admixture estimates in the state of Puebla, Mexico.

Three hundred ninety-three individuals from the Universidad Autónoma de Puebla and its University Hospital were studied to determine the distribution of ABO, MN, Rh-Hr, Duffy, and Diego blood groups; red cell hemoglobin and glucose-6-phosphate dehydrogenase variants; and serum haptoglobins, albumins, and factor Bf types. With the results we estimated that the proportions of black, indian, and white genes are 10.7%, 56.3%, and 33.0%, respectively, in a trihybrid model. Reasons are given as to why the black ancestry may be artifically high, and it is pointed out that independent confirmation with other markers is needed before the figure can be accepted as a true value.

Sindrome de Down e ilegitimidad / Ilegitimacy and Dow syndrome

Por medio de seis marcadores genéticos cuya sensibilidad había sido establecida previamente se determinó la frecuencia de ilegitimidad en una población de 44 familias que tenían en común ser del Distrito Federal y tener un hijo con síndrome de Down por trisomía regular. Se encontraron siete hijos ilegítimos, dos con síndrome de Down y cinco entre los hermanos de los casos índice, lo que representa una frecuencia de 11.1 por ciento. Esa frecuencia es cuatro veces superior a la encontrada por otros autores en una población de la ciudad de Mexíco. A pesar de ese elevado índice de ilegitimidad los hallazgos no apoyan, cuando menos de manera directa, la hipótesis de que en los niños con síndrome de Down se encuentra una mayor frecuencia de ilegitimidad. El análisis de las frecuencias génicas permite establecer que no existe segregación preferencial de alguno de los marcadores en el síndrome de Down y que los sujetos estudiados se encuentran en equilibrio de Hardy- Weinberg

Gene frequencies and admixture estimates in a Mexico City population.

Five hundred and ten students of the Universidad Nacional Autónoma de México were tested to determine the distribution of ABO, MN, Rr-Hr blood groups, and serum haptoglobin, albumin, and Factor Bf types. Based on the results we found that the proportion of Indian and White genes are of 56.16 and 43.84%, respectively in the dihybrid model and 2.93, 56.22, and 40.85% for Blacks, Indians, and Whites in the trihybrid one. The present study reveals a higher proportion of Indian genes in the Mexico City population than estimated in previous publications. Reasons why the present results apply to a much larger group of Mexico City mestizos than the previous ones are given.

A new glucose-6-phosphate dehydrogenase variant, Gd(-) Tepic, characterized by moderate enzyme deficiency and mild episodes of hemolytic anemia.

A 16-year-old Mexican male of Japanese ancestry was found to have a new glucose-6-phosphate dehydrogenase (G-6-PD) deficient variant, named Gd(-) Tepic after the birthplace of the maternal grandmother. A younger brother was also affected and the two sisters were heterozygous. The mother, an obligatory heterozygote, did not show the abnormal variant and the possible explanation of this phenomenon is discussed. From the clinical standpoint, the propositus has had three mild hemolytic episodes while his siblings are so far asymptomatic.

Gc types in one Indian group and one Mestizo Mexican group.

The distribution of Gc types was investigated in an Indian group residing in Cuetzalan, Puebla, and in a Mestizo group from Mexico City. Gc1 and Gc2 gene frequencies were 0.862 and 0.138 in Cuetzalan, and 0.858 and 0.142 in Mexico City. These figures are similar to those obtained by other authors in one Northeastern Mexican City. A literature review showed that there appears to be a pattern of high Gc2 frequency in most Brazilian Indians (above 0.3) in contrast to a low frequency (below 0.2) in most other Amerindian groups studied.

Deficiencia de lactasa y el sindrome de colon irritable. / Lactase deficiency and irritable colon syndrome

Se ivestigo la posible relacion entre el sindrome de colon iritable y la deficiencia de lactasa intestinal.Cincuenta y cinco (66%) de 83 pacientes con colon irritable tuvieron hipolactasia, proporcion similar a la de otros pacientes sin colon irritable en nuestra Institucion. Por otro lado, cuando menos el 56% de los sujetos deficientes que se sometieron a una dieta sin lactosa, mostraron clara mejoria clinica. Este estudio piloto plantea la necesidad de realizar una investigacion doble ciego para esclarecer el papel de la hipolactasia en el sindrome de colon irritabl

Distribution of ABO blood groups and other genetic markers in mothers of infants with congenital malformations.

The distribution of ABO and Rh (antigen D) blood groups and of serum albumin, haptoglobin and transferrin variants, in a group of mothers of malformed newborns was investigated. In the first phase of the study, the results showed borderline statistical differences in the distribution of the transferrin types between the study group and a suitable control population. The second phase of the research, where only transferrin phenotypes were studied, showed the same trend as in the first one, but the results were not statistically significant. We conclude that probably there are no true distribution differences, but that it would be desirable to study this problem in a different ethnic group.

Glucosa-6-fosfato deshidrogenasa Gd(-) Distrito Federal. Nueva variante asociada a deficiencia enzimatica moderada y anemia hemolitica ocasional. / Glucose-6-phosphate dehydrogenase (Gd-) Distrito Federal. A new variant associated with moderate enzyme deficiency and mild hemolytic anemia

Se describe una nueva variante de Glucosa-6-fosfato deshidrogenasa eritrocitica, la G-6-PD Gd(-) Distrito Federal, caracterizada por tener deficiencia enzimatica moderada y anemia hemolitica ocasional. El caso indice fue un nino de un ano y medio que habia presentado en dos ocasiones cuadros clinicos sugestivos de anemia hemolitica aguda de moderada intensidad. Dado que esta es la quinta variante de G-6-PD descrita originalmente em mexicanos, se plantea la posibilidad de que la deficiencia de G-6-PD en Mexico no sea tan rara como comunmente se cree

Serum atypical pseudocholinesterase and leprosy.

The frequency of the serum atypical pseudochloinesterase variant was significantly higher (p less than 0.005) in a group of 115 lepromatous leprosy patients than in a comparison group of 133 healthy individuals. This finding corroborates the results obtained in the group of patients from India, and supports the contention that the serum atypical pseudocholinesterase is one of the possible genetic factors involved in susceptibility to leprosy.