Coxiella burnetii vaginal shedding and antibody responses in dairy goat herds in a context of clinical Q fever outbreaks

This study, carried out in three goat herds, was aimed at describing individual responses to Q fever infection in an abortive context, focusing on both antibody and shedding levels. Seroprevalence of Coxiella burnetii (Cb) infection and vaginal shedding of 1083 goats were investigated using ELISA and realtime qPCR assays, respectively. At the end of the outbreaks, a seroprevalence of 45.0% was found, and vaginal shedding appeared massive with levels above 10(4) Cb per swab in 42.3% of the whole population and above 10(6) Cb per swab for 90.9% of aborted goats. Susceptible animals (i.e. seronegative nonshedders) were unfrequent (31.2%), most of them being kids (94.7%). Seronegative females were predominant among nonshedders and conversely seropositive ones, predominant among high shedders (above 10(6) Cb per swab). Nevertheless, at least 43.3% of seronegative goats shed bacteria confirming the need of interpreting serology on a herd scale. The subsequent farrowing period was characterized by a significant reduction in the number of clinical cases. Females that had already aborted were more often involved than others. Shedding quantities remained high, particularly for primiparous does, mainly when facing infection for the first time. Thus, Q fever control must be based on both preventive measures directed to the preherd and environmental precautions.     

An Immune-Related Gene Evolved into the Master Sex-Determining Gene in Rainbow Trout, Oncorhynchus mykiss

Since the discovery of Sry in mammals [1, 2], few other master sex-determining genes have been identified in vertebrates [3-7]. To date, all of these genes have been characterized as well-known factors in the sex differentiation pathway, suggesting that the same subset of genes have been repeatedly and independently selected throughout evolution as master sex determinants [8, 9]. Here, we characterized in rainbow trout an unknown gene expressed only in the testis, with a predominant expression during testicular differentiation. This gene is a male-specific genomic sequence that is colocalized along with the sex-determining locus. This gene, named sdY for sexually dimorphic on the Y?chromosome, encodes a protein that displays similarity to the C-terminal domain of interferon regulatory factor 9. The targeted inactivation of sdY in males using zinc-finger nuclease induces ovarian differentiation, and the overexpression of sdY in females using additive transgenesis induces testicular differentiation. Together, these results demonstrate that sdY is a novel vertebrate master sex-determining gene not related to any known sex-differentiating gene. These findings highlight an unexpected evolutionary plasticity in vertebrate sex determination through the demonstration that master sex determinants can arise from the de novo evolution of genes that have not been previously implicated in sex differentiation.     

Its all about connections: hubs and invasion in habitat networks

During the early stages of invasion, the interaction between the features of the invaded landscape, notably its spatial structure, and the internal dynamics of an introduced population has a crucial impact on establishment and spread. By approximating introduction areas as networks of patches linked by dispersal, we characterised their spatial structure with specific metrics and tested their impact on two essential steps of the invasion process: establishment and spread. By combining simulations with experimental introductions of Trichogramma chilonis (Hymenoptera: Trichogrammatidae) in artificial laboratory microcosms, we demonstrated that spread was hindered by clusters and accelerated by hubs but was also affected by small‐population mechanisms prevalent for invasions, such as Allee effects. Establishment was also affected by demographic mechanisms, in interaction with network metrics. These results highlight the importance of considering the demography of invaders as well as the structure of the invaded area to predict the outcome of invasions.     

GAPDH Expression Predicts the Response to R-CHOP,the Tumor Metabolic Status,and the Response of DLBCL Patients to Metabolic Inhibitors

1. Download : Download high-res image (163KB)
2. Download : Download full-size image

     

Antidepressants and pregnancy: risks and benefits for the mother and child

Depression, anxiety disorders, anorexia nervosa and bulimia, all indications for antidepressant use, are common disorders in women of childbearing age. Nevertheless, antidepressant use during the gestational period remains a controversial topic. Given that 50 % of pregnancies are unplanned, the safety of antidepressants during the first trimester of pregnancy, a critical period for foetal development, has become a major public health concern. Until now, most studies suggest that physicians may often under-prescribe or discontinue antidepressants at the time of conception and during pregnancy. This may be a consequence of the concern over the safety of these agents in pregnant women and the risks they may pose to the foetus. In fact, recent studies and warnings from Health Canada and the US Food and Drug Administration have reinforced this uncertainty regarding the adverse effects of antidepressant use on the foetus. On the other hand, discontinuation of antidepressant use during pregnancy was also recently associated with maternal relapse of depression and withdrawal symptoms, which is not optimal for the mother and her foetus. Consequently, women who wish to become pregnant and who suffer from psychiatric disorders are faced with the difficult task of deciding whether to continue or discontinue their antidepressant during pregnancy. At this time, it appears important to take into account all evidence-based data to evaluate the risks/benefits of using antidepressants during the gestational period in order to help mothers make the best choice for themselves, and their infants.