Inter-annual and spatial climatic variability have led to a balance between local fluctuating selection and wide-range directional selection in a perennial grass species.

BACKGROUND AND AIMS: The persistence of a plant population under a specific local climatic regime requires phenotypic adaptation with underlying particular combinations of alleles at adaptive loci. The level of allele diversity at adaptive loci within a natural plant population conditions its potential to evolve, notably towards adaptation to a change in climate. Investigating the environmental factors that contribute to the maintenance of adaptive diversity in populations is thus worthwhile. Within-population allele diversity at adaptive loci can be partly driven by the mean climate at the population site but also by its temporal variability. METHODS: The effects of climate temporal mean and variability on within-population allele diversity at putatively adaptive quantitative trait loci (QTLs) were evaluated using 385 natural populations of Lolium perenne (perennial ryegrass) collected right across Europe. For seven adaptive traits related to reproductive phenology and vegetative potential growth seasonality, the average within-population allele diversity at major QTLs (HeA) was computed. KEY RESULTS: Significant relationships were found between HeA of these traits and the temporal mean and variability of the local climate. These relationships were consistent with functional ecology theory. CONCLUSIONS: Results indicated that temporal variability of local climate has likely led to fluctuating directional selection, which has contributed to the maintenance of allele diversity at adaptive loci and thus potential for further adaptation.

Immune recognition of the 60kD heat shock protein: implications for subsequent fertility.

The 60kD heat shock protein (hsp60) is a highly conserved protein and a dominant antigen of most pathogenic bacteria. In some women, chronic or repeated upper genital tract infections with Chlamydia trachomatis, and possibly with other microorganisms, induces immune sensitization to epitopes of hsp60 that are present in both the microbial and human hsp60. Once a woman becomes sensitized to these conserved epitpes, any subsequent induction of human or bacterial hsp60 expression will reactivate hsp60-sensitized lymphocytes and initiate a pro-inflammatory immune response. Hsp60 is expressed during the early stages of pregnancy, by both the embryo and the maternal decidua. We examined, therefore, whether women who were sensitized to hsp60 experienced less successful pregnancy outcomes compared to women who were not sensitized to this antigen. In women undergoing in vitro fertilization (IVF), the presence of cervical IgA antibodies reactive with the C. trachomatis hsp60 correlated with implantation failure after embryo transfer. Further analysis revealed that an immunodominant epitope for these IgA antibodies was an hsp60 epitope shared between C. trachomatis and man. In subsequent studies of women not undergoing IVF, cervical IgA antibodies to the human hsp60 were identified in 13 of 91 reproductive age women. This antibody was most prevalent in those women with a history of primary infertility (p = 0.003). In addition, cervical anti-hsp60 IgA correlated with the detection of the pro-inflammatory cytokines interferon-gamma (p = 0.001) and tumor necrosis factor-alpha (p = 0.02) in the cervix. Conversely, women with proven fertility had the highest prevalence of the anti-inflammatory cytokine, interleukin 10, in their cervices (p = 0.001). In an analysis of serum samples in a third study, women with a history of two or more consecutive first trimester spontaneous abortions had a higher prevalence (p = 0.01) of IgG antibodies to the human hsp60 (36.8%) than did age matched fertile women (11.1%) or women with primary infertility (11.8%). Immune sensitization to epitopes expressed by the human hsp60 may reduce the probability of a successful pregnancy outcome due to reactivation of hsp60-reactive lymphocytes, induction of a pro-inflammatory cytokine response and interference with early embryo development and/or implantation.

The role of moiré photography in evaluating minor scoliotic curves.

Satisfactory correlation has been observed between the radiographic lateral deviation and moiré documented asymmetry of the trunk in scoliotic curves. The advantage of the moiré method is that it is non-invasive and can document what has been observed for later comparison. This screening method decreases the risk of obtaining too many false positive and negative findings. It also increases the possibility of diagnosing scoliosis earlier than with conventional visual methods and, at the same time, decreases the number of radiographs for minor curves in young patients.