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111.
We report a 20-year-old male patient with an atypical Spitz tumor, located in the dorsal aspect of his left hand, and a positive sentinel axillary lymph node. After lymphadenectomy, 1 of 23 non-sentinel lymph nodes excised was found to contain small multiple deposits of large spindle atypical melanocytes. Reviewing the pertinent literature, 5 of 29 patients with atypical Spitz tumors and positive sentinel nodes who had undergone lymphadenectomy have shown non-sentinel node involvement (17.2%), a proportion similar to that reported in melanoma patients. The exact nature of atypical Spitz tumors and the interpretation of cell deposits detected in sentinel nodes are still debated; data regarding the non-sentinel lymph node involvement in patients with atypical Spitz tumors may contribute to better understand the real biological potential of such tumors.  相似文献   
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BACKGROUND: We have recently reported that homozygosity for the minor A-allele of RAGE (receptor for advanced glycation end products) -374T/A polymorphism may exert a protective effect toward the development of angiographic coronary artery disease (CAD). Here we focused on the putative involvement of this functional RAGE polymorphism on the severity of coronary atherosclerosis as assessed by angiography. METHODS: In a total of 234 consecutive Caucasian patients with angiographically proven CAD, the severity of coronary atherosclerosis was assessed by the number of diseased vessels (greater than 50% stenosis). Genotyping for the -374T/A variant was performed by means of PCR-RFLPs. RESULTS: The mean number of diseased vessels was significantly lower in patients with the AA genotype (1.47+/-0.68) than in those with the AT or TT genotype (1.88+/-0.82, p=0.029). After confounding variables were controlled for, the number of diseased vessels remained significantly different in the AA genotype carriers from that in the AT or TT carriers (p=0.041, ANCOVA). CONCLUSIONS: Our data suggest that the RAGE -374T/A polymorphism is one of the likely candidate determinants for the genetic variance of disease phenotype in coronary atherosclerosis.  相似文献   
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Background: Cigarette smoking, a cardiovascular risk factor leading to oxygen free radical formation, is involved in the development of serious pathological conditions. On the other hand, a healthy diet and adequate supplementation can help prevent many diseases. The aim of our study was to evaluate in healthy light smokers the effects of supplementation with mixed fruit and vegetable juice powder concentrate on homocysteine metabolism and oxidative status. Methods: In this pilot study, 32 healthy volunteers, 16 light smokers and 16 non-smokers, on twice daily supplementation were monitored at time zero and after 30 days. Plasma homocysteine, and serum vitamin B(12) and folate concentrations were measured by immunoenzymatic assays; reactive oxygen species, total antioxidant capacity and thiol groups by spectrophotometric methods; and total and free malondialdehyde concentrations by gas chromatography-mass spectrometry with isotopic dilution. Results: Baseline free malondialdehyde concentrations were significantly higher in smokers than in non-smokers and normalised after 30-day supplementation. Baseline results for all the other parameters remained unchanged after supplementation, with no significant differences between smokers and non-smokers. Conclusion: This is the first study showing a significant decrease in free malondialdehyde levels in light smokers after 1-month phytonutrient supplementation.  相似文献   
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Systolic anterior motion of the mitral valve (MV) with dynamic left ventricular (LV) outflow tract obstruction is a well known phenomenon in hypertrophic cardiomyopathy, or other forms of hyper-dynamic LV function associated with hypovolemic states, or LV hypertrophy. We report three patients with MV prolapse in the absence of the above predisposing factors, who developed an LV outflow dynamic gradient during acute transient myocardial ischemia. An interaction between structural abnormalities of the mitral apparatus and ischemia-dependent LV shape deformity most likely accounted for the outflow gradient.  相似文献   
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Background  

With increasing experience, sentinel node navigation has been applied even to gastric cancer. Sentinel lymph nodes are identified by injecting lymphatic tracer dye and radioisotope-labeled particles around a gastric tumor into the submucosa endoscopically. The aim of this video was to demonstrate the feasibility of laparoscopic sentinel node navigation (SLN) in gastric cancer.  相似文献   
120.
Many cyanobacterial species are able to produce cyanotoxins as secondary metabolites. Among them, microcystins (MC) are a group of around 80 congeners of toxic cyclic heptapeptides. MC-LR is the most studied MC congener, in view of its high acute hepatotoxicity and tumor promoting activity. Humans may be exposed to cyanotoxins through several routes, the oral one being the most important. The accepted pathway for MC-LR detoxication and excretion in the urine is GSH conjugation. The GSH adduct (GS-MCLR) formation has been shown to occur spontaneously and enzymatically, catalyzed by glutathione transferases (GSTs). The enzymatic reaction has been reported but not characterized both in vitro and in vivo in animal and plant species. No data are available on humans. In the present work, the MC-LR conjugation with GSH catalyzed by five recombinant human GSTs (A1-1, A3-3, M1-1, P1-1, and T1-1) has been characterized for the first time. All GSTs are able to catalyze the reaction; kinetic parameters K(m), k(cat), and their relative specific activities to form GS-MCLR were derived (T1-1 > A1-1 > M1-1 > A3-3 ? P1-1). In the range of MC tested concentrations used (0.25-50 μM) GSTT1-1 and A1-1 showed a typical saturation curve with similar affinity for MC-LR (≈80 μM; k(cat) values 0.18 and 0.10 min(-1), respectively), A3-3 and M1-1 were linear, whereas GSTP1-1 showed a temperature-dependent sigmoidal allosteric curve with a k(cat) = 0.11 min(-1). The enzymes mainly expressed in the liver and gastrointestinal tract, GSTA1-1, T1-1, and M1-1, seemed to be mainly involved in the MC-LR detoxification after oral exposure, whereas P1-1 kinetics and location in the skin suggest a role related to dermal exposure. Considering the high frequency of some GST polymorphism, especially M1 and T1 gene deletion, with complete loss in activity, this information could be the first step to identify groups of individual at higher risk associated with MC exposure.  相似文献   
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