No abstract

Extraordinarily high rates of CSA were observed for sexual minorities, and sexual minorities were more likely to have incident HIV or STIs, in this U.S. population survey. Identifying the impact of CSA among heterosexuals and sexual minorities in the US is a crucial first step in examining the sequelae of CSA, including the potential mediators of mental health and substance abuse disorders in the relationship between CSA and sexual risk taking.

No abstract

The Wnt signaling pathway has been implicated in a variety of biological events inducing neurogenesis. In this study, we aim to investigate the expression pattern of various components of the Wnt pathway including β-catenin and its partners LEF-1/TCF-4, GSK-3β and their nuclear target genes such as c-myc and cyclin D1 during mouse brain development. We performed a series of Western blot and immunohistochemistry of brain cortex, brainstem, and cerebellum which revealed differential accumulation of these proteins in different types of brain cells including neurons, astrocytes, and oligodendrocytes at different developmental stages. Intense cytoplasmic immunolabeling of β-catenin in 5 day old neurons throughout the cortex and brainstem significantly decreased as the brain developed, whereas the level of GSK-3β, the protein that phosphorylates β-catenin and causes its destabilization, increased during brain maturation. On the other hand, high level accumulation of LEF-1 and TCF-4 in neurons and astrocytes at the early stage of brain development diminished at the later stages. Interestingly, while the majority of LEF-1 and TCF-4 immunoreactivity was detected in the cytoplasm of neurons, it was evident that both proteins accumulated in the nuclei of astrocytes. Examination of cyclin D1, a protein that controls the cell cycle and proliferation, exhibited an intense staining in the nuclei of astrocytes throughout brain parenchyma during development. Interestingly, cyclin D was found in the cytoplasm of neurons from cortex, brainstem, and cerebellum during brain development. These data provide compelling evidence for the differential expression of the Wnt signaling pathway during brain development, and suggest that these signaling pathways may function differently in various brain regions and cell types.