No abstract

Background Evidence demonstrates that the T allele of the single-nucleotide polymorphism rs405509 in the apolipoprotein E (APOE) promoter is a risk factor for Alzheimer’s disease (AD). However, it is unknown whether rs405509 T allele synergizes to the APOE ε4 allele in influencing cognition and brain structure. Methods We analyzed the interaction of the rs405509 T allele and the APOE ε4 allele on cognitive ability and brain gray matter volume (GMV) among the elderly people. The subjects were grouped into four groups according to APOE and rs405509 genotypes. Results Significant interactions were found between rs405509 and APOE on general mental status, memory and attention. Analysis of the whole brain gray matter showed a significantly positive interaction between rs405509 and APOE on the right inferior temporal gyrus and the right fusiform gyrus (alphasim correction p<0.001).Additionally, there was a significant relationship between cognitive ability and GMV. Conclusions The data indicates that the APOE rs405509 T homozygote modulates effect of APOE ε4 on both cognitive performance and brain gray matter structure.

No abstract

We use angular size versus redshift data for galaxy clusters provided by Bonamente and collaborators to place constraints on model parameters of constant and time-evolving dark energy cosmological models. These constraints are compatible with those from other recent data, but are not very restrictive. A joint analysis of the galaxy cluster angular-size data with the more restrictive baryon acoustic oscillation peak length scale and supernova Type Ia apparent-magnitude data, favors a spatially flat cosmological model currently dominated by a time-independent cosmological constant, but does not exclude time-varying dark energy.