Antiviral responses of human Leydig cells to mumps virus infection or poly I:C stimulation

International audienceBACKGROUND: The immuno-privileged status of the testis is essential to the maintenance of its functions, and innate immunity is likely to play a key role in limiting harmful viral infections, as demonstrated in the rat. In men mumps virus infects Leydig cells and has deleterious effects on testosterone production and spermatogenesis. The aim of this study was to test whether mumps virus infection of isolated human Leydig cells was associated with an inhibition of their innate antiviral defences. METHODS: Leydig cell production of mRNA and protein for interferons (IFNs) and of three antiviral proteins-2'5' oligoadenylate synthetase (2'5'OAS), double-stranded RNA-activated protein kinase (PKR) and MxA-was investigated, in the absence or presence of mumps virus or viral stimuli including poly I:C, a mimetic of RNA viruses replication product. RESULTS: Stimulated or not, human Leydig cells appeared unable to produce routinely detectable IFNs alpha, beta and gamma. Although the level of PKR remained unchanged after stimulation, the expression of 2'5'OAS and MxA was enhanced following either mumps virus or poly I:C exposure (P < 0.05 versus control). CONCLUSIONS: Overall, our results demonstrate that mumps virus replication in human Leydig cells is not associated with a specific inhibition of IFNs or 2'5'OAS, MxA and PKR production and that these cells display relatively weak endogenous antiviral abilities, as opposed to their rat counterparts

Edaphic specialization in relation to termite mounds in Katanga (DR Congo): A reciprocal transplant experiment with congeneric tree species

Question: Do termitophilous and non-termitophilous trees of dry tropical woodlands show local adaptation? Location: Region of Lubumbashi, Upper Katanga, DR Congo. Methods: Three pairs of congeneric tree species showing strict edaphic specialization with respect to termite mounds, Combretum molle (termitophilous, T)/C. collinum (non-termitophilous, NT); Strychnos potatorum (T)/S. spinosa (NT), Ziziphus mucronata (T)/Z. abyssinica (NT), were used in a reciprocal transplant experiment in situ. Seedlings were reciprocally transplanted on termite mounds and in the surrounding matrix in a miombo woodland. Growth (height and number of leaves) and survival were monitored for 30 months. Soil physical and chemical properties, and available water, were assessed on and off mounds. Results: Growth was little affected by habitat; only one species showed better growth in its home habitat (S. spinosa in the matrix). Survival was strongly affected by habitat, in opposite directions consistent with species’ habitat specialization. Termitophilous species experienced a very high mortality rate in the matrix, especially during the dry season. Available water content was higher in termite mound soil than in the matrix soil. Conclusions: Termitophilous and non-termitophilous tree species show local adaptation at the seedling stage, expressed mostly as different patterns of mortality in the dry season. The results point to water supply as a critical factor in the edaphic specialization of termitophilous species. In contrast, the higher mortality of non-termitophilous species on termite mounds is not explained by water stress.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Appropriate Education, Juvenile Corrections, and No Child Left Behind

The No Child Left Behind (NCLB) Act of 2001 promotes high-quality educational services for all children and youths, regardless of race, gender, ethnicity, disability, income, or background. Despite the law\u27s laudable goals, one group continues to be left behind: youths who are incarcerated in juvenile correctional facilities. These youths--particularly those with emotional or behavioral disorders--often fail to receive high-quality educational services for a multitude of reasons. The authors review current knowledge about youths with disabilities in juvenile corrections and factors associated with high-quality education programs. They then examine aspects of NCLB in the context of current practices in correctional education and conclude with a brief discussion of how NCLB might be used to improve education programs for incarcerated youths