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981.
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Hepatitis C virus infection can be associated with different extrahepatic manifestations, including lichen planus; however, no clear role for HCV in their pathogenesis has been established. T cells were isolated from lichen biopsy specimens of 7 HCV positive patients with oral lichen planus. HCV-specific CD4(+) T-cell lines were obtained in 4 patients from lichen lesions but only in 2 of them from the peripheral blood. Different clonal populations were found in oral tissue and peripheral blood of individual patients, as shown by TCR-Vbeta analysis of antigen-specific T cells. Frequency of HCV-specific CD8(+) cells tested with 4 different HCV tetramers was significantly higher in the lichen tissue than in the circulation; moreover, lichen-derived HCV-specific CD8(+) T cells showed the phenotype of recently activated T cells because most of them were CD69(+) and produced interferon gamma (IFN-gamma) but expanded poorly in vitro upon antigen stimulation. The specificity of HCV-reactive T-cell recruitment into the lichen tissue was further confirmed by the absence of HBV-specific T cells within lichen lesions in 3 additional patients with lichen planus associated with HBV infection. Our study shows HCV-specific T-cell responses at the site of the lesions of an HCV-associated dermatologic disease, sustained by HCV-specific T cells with phenotypic and functional characteristics of terminally differentiated effector cells. In conclusion, this finding and the detection of HCV RNA strands in the lichen tissue strongly suggest a role for HCV-specific T-cell responses in the pathogenesis of oral lichen planus associated with HCV infection.  相似文献   
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Chromosome Research - Cuscuta is a cytogenetically diverse genus, with karyotypes varying 18-fold in chromosome number and 127-fold in genome size. Each of its four subgenera also presents...  相似文献   
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Background

Evidence-based guidelines for the management of localized perinatal adrenal neuroblastoma are not yet available. We describe our preliminary experience managing this tumor with a “wait and see” policy.

Methods

A single-center prospective study (February 2002 to December 2009) was conducted with 12 consecutive patients in whom an adrenal mass was detected antenatally or within the first 3 months of life. Diagnostic workup included the following investigations: measurement of urine catecholamine metabolites, imaging studies (ultrasonography, magnetic resonance imaging, or computed tomography), metaiodobenzylguanidine scintigraphy, and/or core needle biopsy.

Results

The male/female ratio was 1.4:1.0. Median tumor size at presentation was 29 mm (range 10–50 mm). Eight lesions were detected antenatally. Ten lesions were diagnosed as localized neuroblastoma. Of these ten lesions, four were excised because of parental preference (n = 2), tumor enlargement (n = 1) or tumor persistence (n = 1). The remaining six patients underwent watchful clinical observation, which showed progressive tumor shrinkage and complete regression within 10–39 months (median 12.5 months). The final two lesions were small predominantly cystic lesions without a clear-cut diagnosis. They were managed noninvasively. At an overall median follow-up of 109 months (range 30–122 months), all patients are alive and disease-free, although one patient progressed to stage 4 disease despite early excision of the primary tumor.

Conclusions

Spontaneous regression of localized perinatal adrenal neuroblastoma occurs often, and a “wait and see” strategy seems justified in these small infants. Patients with enlarging or stable lesions that have persisted for several months may benefit from surgery, although prompt excision may not prevent tumor progression.  相似文献   
988.
Our aim was to compare traditional C-peptide-based method and insulin-based method with standardized kinetic parameters in the estimation of prehepatic insulin secretion rate (ISR). One-hundred thirty-four subjects with varying degrees of glucose tolerance received an insulin-modified intravenous glucose tolerance test and a standard oral glucose tolerance test with measurement of plasma insulin and C-peptide. From the intravenous glucose tolerance test, we determined insulin kinetics parameters and selected standardized kinetic parameters based on mean values in a selected subgroup. We computed ISR from insulin concentration during the oral glucose tolerance test using these parameters and compared ISR with the standard C-peptide deconvolution approach. We then performed the same comparison in an independent data set (231 subjects). In the first data set, total ISRs from insulin and C-peptide were highly correlated (R(2) = 0.75, P < .0001), although on average different (103 ± 6 vs 108 ± 3 nmol, P < .001). Good correlation was also found in the second data set (R(2) = 0.54, P < .0001). The insulin method somewhat overestimated total ISR (85 ± 5 vs 67 ± 3 nmol, P = .002), in part because of differences in insulin assay. Similar results were obtained for fasting ISR. Despite the modest bias, the insulin and C-peptide methods were consistent in predicting differences between groups (eg, obese vs nonobese) and relationships with other physiological variables (eg, body mass index, insulin resistance). The insulin method estimated first-phase ISR peak similarly to the C-peptide method and better than the simple use of insulin concentration. The insulin-based ISR method compares favorably with the C-peptide approach. The method will be particularly useful in data sets lacking C-peptide to assess β-cell function through models requiring prehepatic secretion.  相似文献   
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990.
BackgroundIn cystic fibrosis (CF) patients the right ventricle (RV) suffers a progressive deterioration, but it is not clear when these changes begin. The aim of this study was to analyze the RV function in CF patients with mild respiratory disease.MethodsColor-Doppler-Echocardiographic studies were prospectively performed in CF adolescent patients and an age-matched control group. Findings were correlated with pulmonary function tests (PFT), genotype, chronic bacterial colonization, pancreatic status and clinical scores. Only patients with mild CF were selected.ResultsThirty seven CF patients and 40 healthy controls were recruited. In CF patients all echocardiographic parameters were abnormal compared to controls. Doppler analysis showed slightly elevated pulmonary artery pressure values, and abnormal relaxation and systolic function for all indexes. No correlation was found with any of the features studied.ConclusionsIn CF patients, abnormalities in the structure and function of the RV may be present at early stages of the disease. These abnormalities are subclinical and do not correlate with clinical scores, PFT, genotype, chronic bacterial colonization or pancreatic insufficiency.  相似文献   
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