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Fluorescence in situ hybridization analysis was performed to evaluate P16 (9p21), P53 (17p13.1), RB1 (13q14), HER2 (17q11.2) genes and chromosomes 3, 7, 9 and 17 in 62 bladder cancer cystectomies. We found chromosome aneusomy ranged between 74.2% and 91.9%. The highest percentage of homozygous deletion was found in the P16 gene (48.4%), while the highest percentage of heterozygous deletion was in the RB1 gene (51.6%). Chromosome 17 aneusomy significantly increased in tumors with higher stage, and RB heterozygous deletion showed a higher percentage of tumors with positive lymph node. Multiple correspondence analysis (MCA) showed four different biological tumor profiles, but only one could be associated with survival, defining the most unfavorable biological profile, characterized by P53 and P16 as homozygous and heterozygous and RB as homozygous deletion. Overall survival was significantly shorter in patients with at least two positive variables out of the five detected by MCA using the Kaplan-Meier's method. The biological stratification of advanced bladder cancer patients is of particular clinical interest, because the assessment of genetic factors predictive of tumor aggressiveness may influence postoperative therapeutic strategies.  相似文献   
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Nicotine is known to decrease body weight in normal rodents and human smokers, whereas nicotine withdrawal or smoking cessation can increase body weight. We have found that mice fed a high fat diet do not show the anorectic effect of chronic nicotine treatment, but do increase their body weight following nicotine withdrawal. Nicotine withdrawal is accompanied by increased expression of the orexigenic peptides neuropeptide Y and Agouti-related protein in the hypothalamus, and decreased expression of the metabolic protein uncoupling protein-3 in brown adipose tissue. These data suggest that diet can influence the ability of nicotine to modulate body weight regulation and demonstrate that chronic nicotine exposure results in adaptive changes in central and peripheral molecules which regulate feeding behavior and energy metabolism.  相似文献   
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Vitamin D (vitD) low status is currently considered a main environmental factor in multiple sclerosis (MS) etiology and pathogenesis. VitD and its metabolites are highly hydrophobic and circulate mostly bound to the vitamin D binding protein (DBP) and with lower affinity to albumin, while less than 1% are in a free form. The aim of this study was to investigate whether the circulating levels of either of the two vitD plasma carriers and/or their relationship are altered in MS. We measured DBP and albumin plasma levels in 28 MS patients and 24 healthy controls. MS patients were found to have higher DBP levels than healthy subjects. Concomitant interferon beta therapy did not influence DBP concentration, and the difference with the control group was significant in both females and males. No significant correlation between DBP and albumin levels was observed either in healthy controls or in patients. These observations suggest the involvement of DBP in the patho-physiology of MS.  相似文献   
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