Comparative Analysis of Gene Regulation by the Transcription Factor PPARα between Mouse and Human

Studies in mice have shown that PPARalpha is an important regulator of hepatic lipid metabolism and the acute phase response. However, little information is available on the role of PPARalpha in human liver. Here we set out to compare the function of PPARalpha in mouse and human hepatocytes via analysis of target gene regulation

Quantitative Electronenmikroskopie und Neue Materialien

Severe acute malnutrition (SAM) accounts for approximately 1 million child deaths per year. High mortality is linked with comorbidities, such as diarrhea and pneumonia.The aim of this systematic review was to determine the extent to which carbohydrate malabsorption occurs in children with SAM.The PubMed and Embase databases were searched. Reference lists of selected articles were checked.All observational and controlled intervention studies involving children with SAM in which direct or indirect measures of carbohydrate absorption were analyzed were eligible for inclusion. A total of 20 articles were selected for this review.Most studies reported carbohydrate malabsorption, particularly lactose malabsorption, and suggested an increase in diarrhea and reduced weight gain in children on a lactose-containing diet. As most studies reviewed were observational, there was no conclusive scientific evidence of a causal relationship between lactose malabsorption and a worse clinical outcome among malnourished children.The combined data indicate that carbohydrate malabsorption is prevalent in children with SAM. Additional well-designed intervention studies are needed to determine whether outcomes of SAM complicated by carbohydrate malabsorption could be improved by altering the carbohydrate/lactose content of therapeutic feeds and to elucidate the precise mechanisms involved

Measurement of parameters of cholic acid kinetics in plasma using a microscale stable isotope dilution technique:application to rodents and humans

A stable isotope dilution method is described that allows measurement of cholic acid (CA) kinetics, that is, pool size, fractional turnover rate (FTR), and synthesis rate in trace, rats, and humans. Decay of administered [2,2,4,4-H-2(4)]CA enrichment was measured in time in 50-mul plasma samples by gas-liquid chromatography/electron capture negative chemical ionization-mass spectrometry, applying the pentafluorobenzyl-trimethylsilyl derivative. The kinetic data expressed species-dependent differences. The CA pool sizes were 16.8 +/- 2.1, 10.6 +/- 1.2, and 2.4 +/- 0.7 mu mol/ 100 g body weight for mice, rats, and humans, respectively. The FTR values were 0.44 +/- 0.03, 0.88 +/- 0.10, and 0.46 +/- 0.14 per day for mice, rats, and humans. The corresponding synthesis rates were 7.3 +/- 1.6, 9.3 +/- 0.1, and 1.0 +/- 0.2 mu mol/100 g body weight per day. The human data agreed well with literature data obtained by conventional isotope dilution techniques. For rats and mice these are the first reported isotope dilution data. The method was validated by confirmation of isotopic equilibrium between biliary CA and plasma CA in the rat. Its applicability was demonstrated by the observation of increased CA FTR and CA synthesis rate in rats fed cholestyramine, which is known to increase fecal bile acid excretion. The presented stable isotope dilution method enables the determination of CA kinetic parameters in small plasma samples. The method can be applied in unanesthetized rodents with an intact enterohepatic circulation and may also be valuable when studying the development of human neonatal bile acid kinetics