Mammary gland morphology in Sprague-Dawley rats following treatment with an organochlorine mixture in utero and neonatal genistein.

In a related reproductive toxicology study designed to investigate the effects of in utero exposure to environmental toxicants and potential interaction with postnatal genistein, gross enlargement of thoracic mammary glands was observed in female offspring at 200 days of age. Therefore, the objective of this study was to analyze the effect of in utero exposure to a mixture of toxicants on mammary gland morphology. Time-mated Sprague-Dawley rats were treated on days 9-16 of gestation with vehicle or a mixture of environmental toxicants at 1x the acceptable daily intake. Furthermore, it is unclear whether postnatal exposure to phytoestrogens in soy formulas poses breast cancer benefit or risk, and potential interactions with environmental toxicants are unknown. Therefore, half the female pups from each treatment group received either subcutaneous vehicle or genistein (10 microg/g body weight [bw]/day) on postnatal days 2-8. Following necropsy at 200 days of age, a pathologist, blinded to treatment groups, examined mammary gland histopathology. Only mild histological changes were found in mammary glands of rats exposed to the mixture in utero while pronounced ductal hyperplasia, lactational changes, and fibrosis were observed in mammary glands from the genistein group and were more prominent in the mixture + genistein group. Mammary glands of the control group were histologically normal. Collectively, our results reveal that postnatal exposure to pharmacological levels of genistein induces profound morphological changes in the mammary glands of adult female rats, and that high levels of phytoestrogens possess the potential to modulate the toxicological effects of toxicant mixtures.     

Localisation of drug permeability along the rat small intestine, using markers of the paracellular, transcellular and some transporter routes

The small intestine is the major site of drug absorption. Some reports in the literature have evoked the concept of “absorption windows” in the small intestine: are there specific regions where drug absorption is significantly higher than others? To investigate this question, we used an everted gut sac method to study the permeability of drugs and markers every 3–4 cm down the entire small intestine in rat. These markers were chosen to be representative of the mechanisms by which drugs cross the small intestinal mucosa: paracellular and transcellular passive diffusion, via influx transporters, and a drug (digoxin) that is effluxed from cells by P-glycoprotein (P-gp). The passive diffusion and influx transporter markers gave similar profiles with a plateau of permeability along the jejunum, and with the exception of L-Dopa, lower permeability in the ileum. Digoxin showed a linear decrease in the profile from the proximal jejunum to the ileum. Permeability in the duodenum was two to three times lower than the jejunum for all compounds. There were no narrow specific regions of high permeability and so the concept of discrete “absorption windows” along the small intestine as suggested from some pharmacokinetic studies may be related to other effects such as pH and/or solubility.     

Promises and pitfalls of untargeted metabolomics

Metabolomics is one of the newer omics fields, and has enabled researchers to complement genomic and protein level analysis of disease with both semi-quantitative and quantitative metabolite levels, which are the chemical mediators that constitute a given phenotype. Over more than a decade, methodologies have advanced for both targeted (quantification of specific analytes) as well as untargeted metabolomics (biomarker discovery and global metabolite profiling). Untargeted metabolomics is especially useful when there is no a priori metabolic hypothesis. Liquid chromatography coupled to mass spectrometry (LC-MS) has been the preferred choice for untargeted metabolomics, given the versatility in metabolite coverage and sensitivity of these instruments. Resolving and profiling many hundreds to thousands of metabolites with varying chemical properties in a biological sample presents unique challenges, or pitfalls. In this review, we address the various obstacles and corrective measures available in four major aspects associated with an untargeted metabolomics experiment: (1) experimental design, (2) pre-analytical (sample collection and preparation), (3) analytical (chromatography and detection), and (4) post-analytical (data processing).     

Dietary Therapies: Emerging Paradigms in Therapy of Drug Resistant Epilepsy in Children

About one-third of childhood epilepsy ultimately becomes drug resistant epilepsy. Only about one-third of drug resistant epilepsy is amenable for epilepsy surgery. Epilepsy surgery and vagal nerve stimulation is still beyond the reach of huge proportion of children with pharmacoresistant epilepsy. Ketogenic diet (KD) has been in use for almost a century now all over the world for drug resistant epilepsy, although in between there was a decline in its popularity with advent of newer antiepileptic drugs like valproate, phenytoin and carbamazepine. Again from 1990s there was resurgence of interest in KD for pharmacoresistant epilepsy and in the last two decades several randomized controlled trials and systemic reviews have proved its efficacy beyond any suspicion. Ketogenic diet is a high fat low carbohydrate and low protein diet, which has been found to reduce epileptogenesis in body most probably by production of ketone bodies. Modified Atkin’s Diet (MAD) first introduced in 2003 and Low Glycemic Index Treatment (LGIT) first introduced in 2005 are another two dietary therapies, which are less restrictive, more palatable with fewer adverse effects and comparable efficacy. MAD is also a high fat, low carbohydrate diet, in which high sugar foods are discouraged and protein and fluids are unrestricted. In LGIT, only carbohydrates with Glycemic Index <50 are allowed and carbohydrate intake is restricted to 40–60 g per day. Medium Chain Triglyceride KD (MCT KD) is another alternative, in which there are more food choices as compared to classic KD, with comparable efficacy.     

Financial incentives,timing of births,and infant health: a closer look into the delivery room

As a result of strong financial incentives created by the German parental leave reform on January 1, 2007, some 1000 births have been shifted from the last days of 2006 to the first days of 2007, especially by working mothers. This fact is already described in the literature, yet there is no evidence as to the mechanisms and only scarce evidence regarding the effects on newborn health. I use new data to study the timing of C-sections and the induction of births around the day the reform took effect. I estimate that postponed C-sections and inductions account for nearly 80 % of the pre-reform shortfall and nearly 90 % of the post-reform excess number of births. Despite concerns voiced by doctors before the reform, hardly any evidence can be found for detrimental health effects of those shifts, as measured by changes in gestational age, birth weight, APGAR scores, neonatal mortality, or hospitalization.