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Multiple sclerosis (MS) is an auto-immune disease whose etiology remains controversial. Both genetic and environmental factors are thought to be involved in the risk of developing the disease. The purpose of our study was to assess the association of Vitamin D receptor (VDR) polymorphisms with MS and to investigate the interaction of these polymorphisms with vitamin D levels. A total of 179 Sicilian subjects, including 104 MS patients and 75 healthy controls, were studied. The most common VDR polymorphisms (Fok-I, Bsm-I, Taq-I and Apa-I) were genotyped by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) analyses in both groups and serum 25-hydroxyvitamin D [25(OH)D] levels were determined in MS patients by high-performance liquid chromatography (HPLC). The distribution of genotype and allele frequencies of the four VDR polymorphisms did not differ significantly between MS patients and healthy controls, and were unrelated to the forms and the course of MS. Low serum levels of 25(OH)D were observed in MS patients but no association was observed between VDR and 25(OH)D levels except for Fok-I. Moreover, MS patients with FF and Ff genotype had a significantly lower serum levels of 25(OH)D compared with ff carriers (P < 0.05 FF vs Ff and Ff vs ff). Our findings showed no association between VDR polymorphisms and risk of MS. Interestingly, F allele could confer a genetic predisposition to lower 25(OH)D levels.  相似文献   
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Background and aimsA single high-fat meal may induce endothelial activation and dysfunction in both normal subjects and in patients with type 2 diabetes. The aim of this study was to assess the effect of a high-fat meal on endothelial function in patients with the metabolic syndrome.Methods and resultsTwenty-five patients with the metabolic syndrome (ATP III criteria) were matched for sex, age and body mass index with 25 subjects without the metabolic syndrome. All subjects ate under supervision a high fat meal (760 calories) with 59% energy from fat, 12% energy from protein and 29% energy from carbohydrates. Compared with the control group, subjects with the metabolic syndrome had reduced endothelial function, as assessed with the l-arginine test, and higher circulating levels of TNF-α. Following the high-fat meal, both triglyceride and TNF-α levels increased more in subjects with the metabolic syndrome than in subjects without, while endothelial function decreased more in subjects with the metabolic syndrome. There was a significant relation between increases in TNF-α levels and decreases in endothelial function score in subjects with the metabolic syndrome (r = −0.39, P = 0.03).ConclusionTNF-α levels are increased in subjects with the metabolic syndrome; moreover, a high-fat meal produces further increase in its levels associated with endothelial dysfunction.  相似文献   
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Background: Soldered or cast bars are used as a standard of care in attachment systems supporting maxillary and mandibular implant overdentures. When failures of these bars occur, currently there is a lack of evidence in relation to their specific etiology, location, or nature. Purpose: To investigate the failure process of a case series of six failed soldered bars, four intact soldered bars, and one intact cast milled bar, which had been supporting implant overdentures. Materials and Methods: A total of 11 different overdenture bars were removed from patients with different configuration of opposing arches. A failed bar (FB) group (n = 6) had failed soldered overdenture bars, which were recovered from patients following up to 2 years of wear before requiring prosthodontic maintenance and repair. An intact bar (IB) group (n = 5) had both soldered bars and a single cast milled bar, which had been worn by patients for 2 to 5 years prior to receiving other aspects of prosthodontic maintenance. All bars were examined using scanning electron microscopy to establish the possible mode of failure (FB) or to identify evidence of potential failure in the future (IB). Results: Evidence of a progressive failure mode of corrosion fatigue and creep were observed on all the FB and IB usually around the solder areas and nonoxidizing gold cylinder. Fatigue and creep were also observed in all the IB. Where the level of corrosion was substantial, there was no evidence of wear from the matrices of the attachment system. Evidence of an instantaneous failure mode, ductile and brittle overload, was observed on the fracture surfaces of all the FB, within the solder and the nonoxidizing gold cylinders, at the solder/cylinder interface. Conclusion: Corrosion, followed by corrosion fatigue, appears to be a key factor in the onset of the failure process for overdenture bars in this case series of both maxillary and mandibular overdentures. Limited sample size and lack of standardization identify trends only but prevent broad interpretation of the findings.  相似文献   
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Crack cocaine addiction is a public health problem in Brazil. It is an endemicdisease that affects rural and urban areas. The Ministry of Health has launchedemergency programs for the treatment of dependents and to combat drug trafficking.Recognition of dermatological signs of this disease is important because through themthe diagnosis can be suspected and early treatment of patients with crack cocaineaddiction be provided.  相似文献   
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