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11.
A skin-specific block in NF-κB signaling leads to hyperproliferation of the keratinocytes, inflammation, and spontaneous development of squamous cell carcinoma (SCC). Here we show that an inhibition of NF-κB signaling in keratinocytes, via the expression of the super-repressor/ degradation-resistant form of the IκBα protein (IκBαDN), interferes with the growth arrest induced by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA). The IκBαDN cells are able to overcome the TPA-induced cell cycle block. Although SCC development as well as hyperproliferation due to IκBαDN expression in keratinocytes is known to require TNFR1 signaling, the effect of IκBαDN on phorbol ester signaling is downstream/independent of TNFR1. These data thus identify an interaction between IκBαDN and the tumor promoter TPA in the growth regulation of keratinocytes. The proposed mechanism is also likely to be significant in the process of cancer development due to NF-κB inhibition.  相似文献   
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The present study was carried out to ascertain the birth order as a risk factor for schizophrenia on the basis of HLA genetics. India born schizophrenic patients of Siliguri, West Bengal who attended Outpatient Department of Psychiatry, North Bengal Medical College and Hospital were included in the study. After longitudinal follow up of 136 patients and 150 controls matched in age, sex and ethnicity were screened for the study. The typing of HLA was done by PCR-SSP method. The results showed a significantly increased frequency of HLA*A3 among the patients. Further, birth order was studied among HLA*A3 positive 108 patients and 41 controls. Although, results indicated higher incidence of schizophrenia among second children irrespective of sex but it was not found to be statistically significant. However, when the birth order of male and female patients was analyzed separately, a significant decreased incidence of schizophrenia was observed among the third female child. The findings do not corroborate with the earlier findings of association of birth order with schizophrenia.  相似文献   
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Background

The pro-inflammatory status of the elderly triggers most of the age-related diseases such as cancer and atherosclerosis. Atherosclerosis, the leading cause world wide of morbidity and death, is an inflammatory disease influenced by life-style and genetic host factors. Stimuli such as oxLDL or microbial ligands have been proposed to trigger inflammation leading to atherosclerosis. It has recently been shown that oxLDL activates immune cells via the Toll-like receptor (TLR) 4/6 complex. Several common single nucleotide polymorphisms (SNPs) of the TLR system have been associated with atherosclerosis. To investigate the role of TLR-6 we analyzed the association of the TLR-6 SNP Pro249Ser with atherogenesis.

Results

Genotyping of two independent groups with CAD, as well as of healthy controls revealed a significant association of the homozygous genotype with a reduced risk for atherosclerosis (odds ratio: 0.69, 95% CI 0.51-0.95, P?=?0.02). In addition, we found a trend towards an association with the risk of restenosis after transluminal coronary angioplasty (odds ratio: 0.53, 95% CI 0.24-1.16, P?=?0.12). In addition, first evidence is presented that the frequency of this protective genotype increases in a healthy population with age. Taken together, our results define a role for TLR-6 and its genetic variations in modulating the inflammatory response leading to atherosclerosis.

Conclusions

These results may lead to a better risk stratification, and potentially to an improved prophylactic treatment of high-risk populations. Furthermore, the protective effect of this polymorphism may lead to an increase of this genotype in the healthy elderly and may therefore be a novel genetic marker for the well-being during aging.
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IntroductionVaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy.ConclusionsThese findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective.

Trial registration

ClinicalTrials.gov NCT00289224  相似文献   
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Light causes damage to the retina, which is one of the supposed factors for age-related macular degeneration in human. Some animal species show drastic retinal changes when exposed to intense light (e.g. albino rats). Although birds have a pigmented retina, few reports indicated its susceptibility to light damage. To know how light influences a cone-dominated retina (as is the case with human), we examined the effects of moderate light intensity on the retina of white Leghorn chicks (Gallus g. domesticus). The newly hatched chicks were initially acclimatized at 500 lux for 7 days in 12 h light: 12 h dark cycles (12L:12D). From posthatch day (PH) 8 until PH 30, they were exposed to 2000 lux at 12L:12D, 18L:6D (prolonged light) and 24L:0D (constant light) conditions. The retinas were processed for transmission electron microscopy and the level of expressions of rhodopsin, S- and L/M cone opsins, and synaptic proteins (Synaptophysin and PSD-95) were determined by immunohistochemistry and Western blotting. Rearing in 24L:0D condition caused disorganization of photoreceptor outer segments. Consequently, there were significantly decreased expressions of opsins and synaptic proteins, compared to those seen in 12L:12D and 18L:6D conditions. Also, there were ultrastructural changes in outer and inner plexiform layer (OPL, IPL) of the retinas exposed to 24L:0D condition. Our data indicate that the cone-dominated chick retina is affected in constant light condition, with changes (decreased) in opsin levels. Also, photoreceptor alterations lead to an overall decrease in synaptic protein expressions in OPL and IPL and death of degenerated axonal processes in IPL.  相似文献   
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Binocular vision requires an exquisite matching of projections from each eye to form a cohesive representation of the visual world. Eye-specific inputs are anatomically segregated, but in register in the visual thalamus, and overlap within the binocular region of primary visual cortex. Here, we show that the transmembrane protein Ten_m3 regulates the alignment of ipsilateral and contralateral projections. It is expressed in a gradient in the developing visual pathway, which is consistently highest in regions that represent dorsal visual field. Mice that lack Ten_m3 show profound abnormalities in mapping of ipsilateral, but not contralateral, projections, and exhibit pronounced deficits when performing visually mediated behavioural tasks. It is likely that the functional deficits arise from the interocular mismatch, because they are reversed by acute monocular inactivation. We conclude that Ten_m3 plays a key regulatory role in the development of aligned binocular maps, which are required for normal vision.  相似文献   
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