Ancestral Mechanisms in Modern Environments

It is commonly assumed that the desire for a thin female physique and its pathological expression in eating disorders result from a social pressure for thinness. However, such widespread behavior may be better understood not merely as the result of arbitrary social pressure, but as an exaggerated expression of behavior that may have once been adaptive. The reproductive suppression hypothesis suggests that natural selection shaped a mechanism for adjusting female reproduction to socioecological conditions by altering the amount of body fat. In modern Western culture, social and ecological cues, which would have signaled the need for temporary postponement of reproduction in ancestral environments, may now be experienced to an unprecedented intensity and duration.     

First elements of comparison between blood-tissue barriers at cerebral, genital and urinary levels

Fluorescence microscope observations of Trypan Blue distribution gives the demonstration of the blood-tissue barriers. It reveals the similitude between the barriers in choroid plexus, in testis, epididymis and bladder and the difference with the blood-brain barrier. Electron microscope investigations afford a statistical view of relations between structure and vascular permeability and stress the opposition reported above. Membrane specializations of each epithelium often bring forward those which are involved in the barrier. This function is principally assigned to thight junctions. The different morphological aspects encountered lead to the problem of dynamic variations in the configuration of the junctions.     

Genome‐wide SNP analysis identifies major QTL for Salmonella colonization in the chicken

Salmonella‐infected poultry products are a major source of human Salmonella infection. The prophylactic use of antimicrobials in poultry production was recently banned in the EU, increasing the need for alternative methods to control Salmonella infections in poultry flocks. Genetic selection of chickens more resistant to Salmonella colonization provides an attractive means of sustainably controlling the pathogen in commercial poultry flocks and its subsequent entry into the food chain. Analysis of different inbred chickens has shown that individual lines are consistently either susceptible or resistant to the many serovars of Salmonella that have been tested. In this study, two inbred chicken lines with differential susceptibility to Salmonella colonization (6₁^(R) and N^(S)) were used in a backcross experimental design. Unlike previous studies that used a candidate gene approach or low‐density genome‐wide screens, we have exploited a high‐density marker set of 1255 SNPs covering the whole genome to identify quantitative trait loci (QTL). Analysis of log‐transformed caecal bacterial levels between the parental lines revealed a significant difference at 1, 2, 3 and 4 days post‐infection (P < 0.05). Analysis of the genotypes of the backcross (F₁ × N) population (n = 288) revealed four QTL on chromosomes 2, 3, 12 and 25 for the two traits examined in this study: log‐transformed bacterial counts in the caeca and presence of a hardened caseous caecal core. These included one genome‐wide significant QTL on chromosome 2 at 20 Mb and three additional QTL, on chromosomes 3, 12 and 25 at 96, 15 and 1 Mb, respectively, which were significant at the chromosome‐wide level (P < 0.05). The results generated in this study will inform future breeding strategies to control these pathogens in commercial poultry flocks.     

Disappearance of prostaglandins F2α and 15-methyl F2α from amniotic fluid as measured by radioimmunoassay

A sensitive and relatively specific radioimmunoassay for 15 (S) 15 methyl prostaglandin F_2α was used to determine the levels of the drug in amniotic fluid after it had been injected intra-amniotically for termination of second trimester pregnancy. The disappearance of the free acid (tham salt) and methyl ester of the prostaglandin analogue were similar. The results of this preliminary study suggest that the drug rapidly equilibrates in the fluid and this is followed by a slow removal from the amniotic sac. A comparison with a similar study with PGF_2α, revealed that the analogue had a longer half-life in the amniotic fluid.     

Evidence for a wahlund effect in a unique breton community,the bigoudens

A random sample of the Bigoudens community was tested for 16 genetic markers. The existence of silent alleles had to be postulated more often than usual although no minus-minus phenotype was observed. Four explanations may be put forward for this apparent contradiction: selection pressure for homozygosity, inbreeding, true silent alleles and random genetic drift between and within the villages. The degree of inbreeding is unlikely to be high enough to account for our data and some of the silent alleles postulated are not thought to exist. We therefore favour the explanation of genetic differentiation and the so-called Wahlund effect.