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Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case–control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66–0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57–0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69–0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61–0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer.  相似文献   
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BACKGROUND/PURPOSE: Sensitive skin is a condition associated with reduced tolerance to environmental factors and/or the application of topical products, such as cosmetics. Its pathophysiology has not been fully elucidated and few data are available on its prevalence. The aim of this study was to investigate possible correlation between objective sensitivity and skin surface microrelief. METHODS: During an epidemiological survey conducted for a campaign promoted by International Society of Plastic Dermatology in Italy, 243 adult healthy subjects of both sexes with no evident dermatological disorder but positive to the lactic acid stinging test, were submitted to cyanoacrylate stratum corneum stripping from the volar forearm for the determination of the irregularity of the skin surface microrelief (irregularity skin index (ISI)). RESULTS: A significant correlation was found between intensity of symptoms in stingers and ISI (r(s)=-0.47; P<0.001). CONCLUSION: Sensitive skin is common in the healthy population. ISI can contribute towards the identification of subjects with sensitive skin and the development of more specific skin treatments for this prevalent condition.  相似文献   
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Is interleukin 2 a neuromodulator in the brain?   总被引:5,自引:0,他引:5  
A bidirectional flow of information exists between the CNS and the neuroendocrine and immune systems, representing an important homeostatic mechanism in the body. Lymphokines and other products of immunocompetent cells seem to play a crucial role in this communication and seem to exert powerful effects on neurones in the brain. In this article, Giuseppe Nisticò and Giovambattista De Sarro describe the central effects following interleukin 2 (IL-2) microinfusion into several areas of the rat brain. The locus coeruleus seems to be the main site in the brain through which IL-2 exerts soporific effects. In addition, the possible transducing mechanisms coupling IL-2 receptor stimulation and the electroencephalogram (EEG) spectrum power responses elicited from the locus coeruleus seem to involve stimulation of specific receptors coupled to adenylate cyclase through a Gi protein.  相似文献   
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