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AIMS: Recent studies suggest an association between acute inflammation and deterioration of arterial function. The effect of acute inflammation on endothelial function and the role of treatment with statins have not been investigated in subjects with dyslipidaemia. METHODS AND RESULTS: In this randomized, placebo-controlled, double-blind study, we generated a transient systemic inflammation by Salmonella typhi vaccination in 50 volunteers with mild hypercholesterolaemia after 4 days of treatment with atorvastatin 40 mg or placebo once daily. Endothelium-dependent flow-mediated dilation (FMD) of the brachial artery and circulating levels of endothelial and inflammatory markers were measured before and 8 h after the vaccine. Vaccination produced a decline on FMD at 8 h (absolute decrease of 2.55%, P = 0.001), indicating an unfavourable effect on endothelial function. In contrast, in atorvastatin-treated subjects, FMD was preserved after vaccination (decrease of 0.15%, P = 0.005 vs. placebo). The vaccination-induced decline in plasma level of nitric oxide metabolites (by 6.0 micromol/L, P = 0.007) and antioxidant capacity (by 20.6 micromol/L, P = 0.001) in the placebo group were completely abolished by atorvastatin (P = 0.038 and P = 0.005, respectively, vs. placebo). In contrast, atorvastatin had no significant effect on cytokine levels. CONCLUSION: Acute inflammation is aetiologically associated with the deterioration of vasomotor and systemic endothelial function in hypercholesterolaemic patients. Atorvastatin effectively abrogates these deleterious effects.  相似文献   
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We describe a 36-year-old man with advanced multiple myeloma (Salmon and Durie stage III) who developed jaundice and severe cholestasis after a first cure with systemic chemotherapy of vincristine, doxorubicin, and oral dexamethasone (VAD). Serology for hepatitis A, B, and C and for CMV was negative. A liver ultrasound and CT scan showed mild hepatomegaly without evidence of extrahepatic or intrahepatic biliary tree dilatation. A percutaneous liver biopsy revealed perisinusoidal deposits of an abundant slightly eosinophilic, PAS-positive amorphous substance. Immunohistochemistry showed positivity for kappa-light chains and was negative for lambda-light chains, for IgA, IgG, IgM, and IgD immunoglobulins as well as for AA and AL proteins and for amyloid P component. A diagnosis of light chain deposition disease (LCDD) of the liver was made. The patient developed rapid deterioration of liver function, leading to a multisystem dysfunction and death. The occurrence of LCDD in multiple myeloma is close to 5% and myeloma is the underlying disease in two thirds of patients with LCDD. The kidneys are involved in almost all cases of LCDD and renal dysfunction usually reveals the disease. Only three patients with LCDD of the liver without overt renal involvement have been reported so far. This is the first observation of LCDD presenting with jaundice and severe cholestasis shortly after the diagnosis of high tumor mass myeloma, without overt renal involvement, leading rapidly to the patient's death.  相似文献   
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AIM: To study the association of the frequency and pattern of KIT and PDGFRA mutations and clinicopathological factors in a group of patients with gastrointestinal stromal tumors (GIST). METHODS: Thirty patients with GIST were examined. Exons 9, 11, 13, and 17 of the KIT and exons 12 and 18 of the PDGFRA gene were analyzed for the presence of mutations by PCR amplification and direct sequencing. RESULTS: KIT or PDGFRA mutations were detected in 21 of the 30 patients (70%). Sixteen patients had mutations within KIT exon 11, three within KIT exon 9, and two within PDGFRA exon 18. GISTs with KIT exon 9 mutations were predominantly located in the small intestine, showed a spindle cell phenotype, and were assessed as potentially malignant. GISTs with KIT exon 11 mutations were located in the stomach and intestine, showed mainly a spindle cell phenotype, and were scored as potentially malignant (P 〈 0.05). Tumors with KIT exon 11 codon 557/558 deletion/insertion mutations were found to be associated with a potentially malignant clinical behaviour (P 〈 0.003). GISTs with PDGFRA mutations located in stomach showed a mixed cell phenotype and were classified as of very low or low moderate malignant potential. CONCLUSION: Determination of KIT and PDGFRA mutations should be additional parameters for the better prediction of GISTs clinical behaviour. Tumors with deletion/insertion mutations affecting codons 557/558 of the KIT gene seem to represent a distinct subset of malignant GISTs.  相似文献   
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AIMTo investigate the incidence of KIT immunoho-stochemical staining in(GI)stromal tumors(GISTs),and to analyze the clinical manifestations of the tumors and prognostic indicators.METHODSWe retrospectively analyzed 50 cases of Previously diagnosed GISTs.Tissue samples were assessed with KIT(CD117 antigen),CD34,SMA,desmin,S-100,NSE,PCNA,Ki-67,and BCL-2 for immunohistochemical study and pathological characteristics were analyzed for prognostic factors.RESULTSFifteen tumors(30%)were negative in KIT staining.A significant association was observed between gender(male patients14/15)and KIT-negative staining P = 0.003).The patients's mean age was 56.6 years.Tumors developed in stomach(n = 8),small intestine (n = 5),large intestine(n = 1)and oesophagus(n = 1).The mean tumor size was 5.72 cm.The mitotic count ranged from 0-29/50 HPF(mean3.4)and 73% of tumors showed no necrosis.The majority of the tumors(67%)had dual or epithelioid differentiation.Tumors were classified as very low or low risk(n = 7),intermediate risk(n = 5),and high risk(n = 3)groups.Twelve(80%)patients were alive without evidence of residual tumor for an average period of 40.25 mo(12-82 mo);three patients developed metastatic disease to the liver and eventually died within 2-12 mo(median survival8.6 mo).CONCLUSIONA small subgroup of GISTs fulfils the clinical and morphological criteria of these tumors,and lacks KIT expression.These tumors predominantly developed in the stomach,being dual or epithelioid in morphology,which are classified as low risk tumors and presented a better survival status than KIT-positive tumors.The ability to diagnose GISTs still depends on immunohistochemical staining but the research should extend in gene mutations.  相似文献   
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Despite improved hematologic care, multiendocrine dysfunction is a common complication of homozygous transfusion-dependent beta-thalassemia. In this study our goal was to estimate the prevalence of thyroid dysfunction in a large homogenous group of thalassemic patients. Two hundred patients with beta-thalassemia major (100 males and 100 females; mean age, 23.2 +/- 6.7 years; age range 11-43 years), regularly transfused and desferioxamine chelated, were randomly selected from a pool of approximately 800 patients with beta-thalassemia followed in our department. Thyroid function and iron-load status were evaluated by measurements of free thyroxine (FT4), free triiodothyronine (FT3), thyrotropin (TSH), and serum ferritin levels. Of the subgroup of patients who proved to have normal thyroid hormone values, 26 (12 males, 14 females; mean age, 23.6 +/- 6.8 years; age range, 15-36 years) were randomly selected and underwent a standard TRH stimulation test. Thyroid dysfunction was defined as follows: overt hypothyroidism: low FT4 and/or FT3, increased TSH levels; subclinical hypothyroidism: normal FT4, FT3, increased TSH levels; exaggerated TSH response: normal FT4, FT3, normal basal TSH, deltaTSH > or = 21 microIU/mL (TSH levels measured prior and 30 minutes after intravenous TRH administration). Normal thyroid hormone values were found in 167 (83.5%) of the 200 patients studied. Eight (4%) of the remaining patients had overt hypothyroidisim, and 25 (12.5%) had subclinical hypothyroidism. Exaggerated TSH response to TRH was revealed in 7 of the 26 patients with normal hormone values tested (26.9%). Antithyroglobulin and anti-thyroid peroxidase (TPO) antibody titers were negative in 191 patients (95.5%). Mean ferritin levels in hypothyroid and euthyroid patients were 2707.66 +/- 1990.5 mg/L and 2902.9 +/- 1997.3 mg/L, respectively, (p = 0.61), indicating no correlation between ferritin levels and thyroid functional status. Mean ferritin levels in the patients who responded normally to TRH stimulation and in those who overresponded, were 2,586 +/- 1791 mg/L and 3,228 +/- 2473 mg/L, respectively (p = 0.46; NS). Thyroid failure is a rather rare endocrine complication in patients with beta-thalassemic from Greece. In our series, no case of central hypothyroidism was observed. No correlation was found between thyroid functional status and ferritin plasma levels. Approximately 1 of 5 beta-thalassemic patients with normal thyroid hormone values showed an exaggerated TSH response to TRH test. It is to be investigated how many of these patients will establish overt or subclinical hypothyroidism in the future.  相似文献   
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