Hypothesis: multiple factors are associated with the lack of any beneficial effects of oestrogen-replacement therapy in the late postmenopausal stage.
ABSTRACT 1. Epidemiological and clinical studies suggest that women may obtain cognitive benefits from oestrogen-replacement therapy (ERT) during menopause transition rather than in the post-menopausal stages. However, the underlying mechanisms remain to be determined. 2. We propose that long-term oestrogen deficiency may result in abnormal distribution and localization of brain oestrogen receptors, brain mitochondrial dysfunction, septohippocampal cholinergic degeneration and reactive gliosis. These multiple pathogenic factors may account for the lack of any beneficial effects of ERT in post-menopausal women with or without Alzheimer's disease.
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ABSTRACT: A full-length ribosomal protein L15 cDNA from Chironomus riparius (CrRPL15) was identified from the Expressed Sequence Tag (EST) database developed vt 454 pyrosequencing, and expression of the corresponding mRNA was analyzed during different developmental stages and following exposure to Cadmium chloride (Cd) and Silver nanoparticles (AgNPs). The CrRPL15 cDNA contains an open reading frame (ORF) of 615 base pairs (bp) encoding a putative protein of 204 amino acids, with a high level of sequence similarity to RPL15 proteins from other species. The consensus sequence, GXXXXGKS, which is present in other RPL15 proteins, was also present in the putative CrRPL15 protein. The CrRPL15 transcript was present at all life stages, but was most abundant in the eggs. Expression of the CrRPL15 gene was significantly down-regulated in response to exposure to both Cd and AgNPs. In contrast, expression of the heat shock protein 70 (HSP70) gene, a general stress indicator, was significantly up-regulated.Comparative Biochemistry and Physiology Part B Biochemistry and Molecular Biology 07/2011; 159(3):157-62. · 2.07 Impact Factor