Human papillomavirus (HPV) is an etiologic agent for both oropharyngeal and cervical cancers, yet little is known about the interrelationship between oral and cervical HPV infections. Therefore, we ...compared the prevalences and type distributions of oral and cervical HPV infections and evaluated infection concordance in a cross-sectional study within the Women's Interagency HIV Study cohort. Oral rinse and cervical-vaginal lavage samples were concurrently collected from a convenience sample of 172 human immunodeficiency virus (HIV)-positive and 86 HIV-negative women. HPV genomic DNA was detected by PGMY09/11 L1 consensus primer PCR and type specified by reverse line blot hybridization for 37 HPV types and β-globin. Only 26 of the 35 HPV types found to infect the cervix were also found within the oral cavity, and the type distribution for oral HPV infections appeared distinct from that for cervical infections (P < 0.001). Oral HPV infections were less common than cervical infections for both HIV-positive (25.2% versus 76.9%, P < 0.001) and HIV-negative (9.0% versus 44.9%, P < 0.001) women. Oral HPV infections were more common among women with a cervical HPV infection than those without a cervical HPV infection (25.5% versus 7.9%, P = 0.002). The majority of women (207; 93.7%) did not have simultaneous oral and cervical infections by the same HPV type; however, the number of women who did (14; 6.3%) was significantly greater than would be expected by chance (P = 0.0002). Therefore, the oral and cervical reservoirs for HPV infection are likely not entirely independent of one another.
Paraventricular (PVN) and supraoptic nuclei of the hypothalamus maintain homeostasis by modulating pituitary hormonal output. PVN and supraoptic nuclei contain five major cell types: oxytocin-, ...vasopressin-, CRH-, somatostatin-, and TRH-secreting neurons. Sim1, Arnt2, and Otp genes are essential for terminal differentiation of these neurons. One of their common downstream genes, Brn2, is necessary for oxytocin, vasopressin, and CRH cell differentiation. Here we show that Sim2, a paralog of Sim1, contributes to the expression of Trh and Ss genes in the dorsal preoptic area, anterior-periventricular nucleus, and PVN. Sim2 expression overlaps with Trh- and Ss-expressing cells, and Sim2 mutants contain reduced numbers of Trh and Ss cells. Genetically, Sim1 acts upstream of Sim2 and partially compensates for the loss of Sim2. Comparative expression studies at the anterior hypothalamus at early stages reveal that there are separate pools of Trh cells with distinctive molecular codes defined by Sim1 and Sim2 expression. Together with previous reports, our results demonstrate that Sim1 and Otp utilize two common downstream genes, Brn2 and Sim2, to mediate distinctive sets of neuroendocrine hormone gene expression.
SIM1 and ARNT2 are two basic helix-loop-helix/PAS ( Per- Arnt- Sim) transcription factors that control the differentiation of neuroendocrine lineages in the mouse hypothalamus. Heterozygous Sim1 mice ...also develop early onset obesity, possibly due to hypodevelopment of the hypothalamus. Although SIM1 and ARNT2 form heterodimers to direct the same molecular pathway, knowledge of this pathway is limited. To facilitate the identification of their downstream genes, we combined an inducible gene expression system in a neuronal cell line with microarray analysis to screen for their transcriptional targets. This method identified 268 potential target genes of SIM1/ARNT2 that displayed >1.7-fold induced expression. 15 of these genes were subjected to Northern analysis, and a high percentage of them were confirmed to be up-regulated. In vivo, several of these genes showed neuroendocrine hypothalamic expression correlating with that of Sim1. Furthermore, we found that expression of two of these potential targets, the Jak2 and thyroid hormone receptor β2 genes, was lost in the neuroendocrine hypothalamus of the Sim1 mutant. The expression and predicted functions of many of these genes provide new insight into both the Sim1/Arnt2 action in neuroendocrine hypothalamus development and the molecular basis for the Sim1 haplo-insufficient obesity phenotype.
The bHLH-PAS transcription factor SIM1 is required for the development of the paraventricular nucleus (PVN) of the hypothalamus. Mice homozygous for a null allele of Sim1 (Sim1(-/-)) lack a PVN and ...die perinatally. In contrast, we show here that Sim1 heterozygous mice are viable but develop early-onset obesity, with increased linear growth, hyperinsulinemia and hyperleptinemia. Sim1(+/-) mice are hyperphagic but their energy expenditure is not decreased, distinguishing them from other mouse models of early-onset obesity such as deficiencies in leptin and melanocortin receptor 4. Quantitative histological comparison with normal littermates showed that the PVN of Sim1(+/-) mice contains on average 24% fewer cells without a selective loss of any identifiable major cell type. Since acquired lesions in the PVN also induce increased appetite without a decrease in energy expenditure, we propose that abnormalities of PVN development cause the obesity of Sim1(+/-) mice. Severe obesity was described recently in a patient with a balanced translocation disrupting SIM1. Pathways controlling the development of the PVN thus have the potential to cause obesity in both mice and humans.
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