Study of the diversity and short-chain fatty acids production by the bacterial community in overweight and obese Mexican children.

Obesity and overweight are health problems of multifactorial etiology, which may include changes in the microbiome. In Mexico, more than 30 % of the child population between 5 and 11 years of age suffer from being overweight or are obese, which makes it a public health issue in progress. The purpose of this work was to measure the short-chain fatty acid concentration by high-performance liquid chromatography (HPLC), and to characterize the bacterial diversity by ion torrent semiconductor sequencing, of 16S rDNA libraries prepared from stools collected from a sample of well-characterized Mexican children for normal weight, overweight, and obese conditions by anthropometric and biochemical criteria. We found that triglyceride levels are increased in overweight and obese children, who presented altered propionic and butyric acid concentrations in feces. In addition, although the colon microbiota did not show a clear bacterial dysbiosis among the three conditions, the abundance of some particular bacteria was changed with respect to normal controls. We conclude from our results that the imbalance in the abundance of at least nine different bacteria as well as altered short-chain fatty acid concentration in feces is associated to the overweight and obese conditions of Mexican children.

[Evaluation of a breakfast as screening test for the detection of gestational diabetes]. / Evaluación de un desayuno como prueba de tamiz para la detección de diabetes gestacional.

A standard breakfast was evaluated as a screening test (BT) for gestational diabetes in a case-control study. The breakfast had a high carbohydrate content and was designed based on women's preferences in a similar sample. Women were selected with a standard 50 g, 1 hour glucose screening test (GT). Fifteen women had a positive GT and 15 had a negative test. A glucose tolerance test (GTT) and a standard breakfast (719 kcal) were performed to all women. Age, weight, height, tricipital and subscapular skinfold thicknesses were obtained by previously standardized personnel and glucose levels were determined by an automatic technique (oxidase glucose). Ten women had gestational diabetes. Sensitivity and specificity were calculated for the GT and several values of the BT, in order to identify the threshold and optimum time. Concordance of both screening tests with GTT was calculated through Kappa test. For the BT, a sensitivity of 0.90 and specificity of 1.00 with a glucose level > or = 140 mg/L (7.2 mmol/L) at 60 and 90 minutes were found. The 60 minutes timing were preferred due to a shorter waiting time to performed the test. Concordance of GTT with GT and BT was 0.53 and 0.92 respectively, both statistically significant. GT had high frequency of false negative values (6/15) that explain the low kappa value. Standard breakfast can be used as an alternative method for assessing carbohydrate tolerance in pregnancy with a better physiological response in these women.