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51.
Malignant granular cell tumors (MGCTs) are rare neoplasms of uncertain histogenesis. We report a case of MGCT involving a peripheral nerve with peritoneal and omental dissemination in which cytogenetic findings are available. Our results show that MGCTs share some cytogenetic abnormalities with malignant peripheral nerve sheath tumors (MPNSTs), supporting the hypothesis that they may represent histogenetically related lesions.  相似文献   
52.
Circulating levels of cytokines are deeply influenced by aging, and few data about serum chemokines are available. The aim of this study was to evaluate the influence of aging on circulating CXCL10. One hundred forty healthy subjects (70 males and 70 females), 10-79 years of age, underwent fasting plasma glucose, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride, and CXCL8 serum assay. Thyroid hormone testing for thyroid-stimulating hormone (TSH), antithyroglobulin (AbTg), and antithyroperoxidase (AbTPO) autoantibodies and thyroid ultrasonography were performed in all subjects to exclude the presence of clinical or subclinical thyroid disease. Serum CXCL10 levels were assayed in all subjects and found to be increased in 14 of 70 females (20%) and in 4 of 70 males (5.7%) (p = 0.01). In a multiple linear regression model including age, body mass index (BMI), systolic and diastolic blood pressure, glycemia, total cholesterol, HDL, LDL, triglycerides, TSH, AbTPO, AbTg, and CXCL8, only age was significantly related to CXCL10 [C.R. 1.30 (0.28-2.33), p = 0.001]. No relationship was present between CXCL8 serum levels and age, suggesting a specificity of CXCL10 elevation as a function of age. Results of this study, performed in healthy subjects on an age gradient, demonstrate an increase in serum CXCL10 with advancing age overall in females, supporting the hypothesis of enhanced Th1 immune responses in aging.  相似文献   
53.
The surface expression of given HLA class I alleles protects target cells from lysis mediated by natural killer (NK) clones specific for these (or related) alleles. We could define two groups of NK clones specifically recognizing either Cw4 and related C alleles (“group 1”) or Cw3 and related C alleles (“group 2”), respectively. Monoclonal antibodies (mAb) to class I molecules should interfere with the interaction between NK receptors and class I molecules, thus resulting in lysis of protected target cells. However, none of the numerous available mAb to class I molecules had this effect. Therefore, we attempted to select new mAb on the basis of their ability to induce lysis of Cw4- or Cw3-protected lymphoblastoid cell lines by “group 1” or “group 2” NK clones, respectively. From mice immunized with phytohemagglutinin (PHA)-activated lymphocytes expressing either Cw3 or Cw4 alleles, two mAb were selected, the 6A4 (IgG1) and the A6-136 (IgM), on the basis of their ability to induce lysis of protected target cell. Both mAb immunoprecipitated molecules which, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gave two bands of 45 and 12 kDa, typical of the class I heavy chain and β2 microglobulin, respectively. It has been proposed (but not proven), that self major histocompatibility complex class I molecules protect normal cells from autologous NK cell lysis. Thus, we used the 6A4 and A6-136 mAb to assess this possibility directly. Cw4-specific (“group 1”) and Cw3-specific (“group 2”) NK clones were isolated from donors expressing the corresponding (or related) protective C alleles. None of these clones lysed autologous PHA-induced blasts, used as target cells. However, addition of the F(ab′)2 of 6A4 mAb or the A6-136 mAb resulted in lysis of autologous target cells by “group 1” or “group 2” NK clones, respectively. These data provide direct evidence that the expression of class I molecules protects normal cells from lysis by autologous NK cells.  相似文献   
54.
The aim of our study was to investigate a possible influence of monoamine oxydase A (MAO-A), catechol-O-methyltransferase (COMT), serotonin receptor 2A (5-HT2A), dopamine receptor D2 (DRD2), and dopamine receptor D4 (DRD4) gene variants on timing of recurrence in mood disorders. Gene variants were determined using PCR-based techniques in 550 inpatients affected by recurrent mood disorders (major depressives: n = 212; bipolars: n = 338), rapid cycling mood disorder (n = 81), and 663 controls. We investigated possible genetic influences by comparing illness time course of subjects subdivided according to genotype using multivariate analysis of variance (MANOVA). We could not observe a significantly different time course. No demographic and clinical variables such as sex, age or polarity of onset, presence of psychotic features, genetic loading, or education level influenced the observed results. Our results suggest that MAO-A, COMT, 5-HT2A, DRD2, and DRD4 gene variants are not involved in susceptibility toward different time courses in mood disorders.  相似文献   
55.
Several studies indicate that cyclooxygenase-2 (COX-2) is overexpressed in human malignancies, where it produces high levels of prostaglandins and contributes to tumor growth. In this study we have analyzed the expression of COX-2 in a series of 48 skeletal osteosarcomas of different subtypes by immunohistochemistry. In addition, we examined the effects of the specific COX-2 inhibitor Celecoxib on the growth of the human osteosarcoma cell line SaOS-2. Immunoreactivity for COX-2 was observed in 39 out of 48 tumors (81.2%), 30 (76.9%) of which showed a moderate or diffuse immunostaining. Considering the group of 42 primary osteosarcomas, COX-2 immunoreactivity was significantly higher in high grade osteosarcomas, where moderate or diffuse expression was detected in 23 out of 32 cases (71.8%), than in low grade osteosarcomas, where moderate or diffuse expression was detected in 2 out of 10 cases (20%) (P = 0.008, Fisher exact test). In addition, low COX-2 expression was always associated with a good response to chemotherapy (5 out of 5 cases), whereas moderate or diffuse COX-2 expression was associated with a good response in 11 out of 20 cases (55%) (P = 0.12, Fisher exact test). In SaOS-2 osteosarcoma cells, which express COX-2, treatment with Celecoxib determined inhibition of cell proliferation and induction of apoptosis. These results indicate that COX-2 is expressed at high levels in high grade osteosarcomas and support the use of COX-2 inhibitors to improve both the tumor response to chemotherapy and the outcome of osteosarcoma patients.  相似文献   
56.
Using short term CTL lines derived from HLA A2/Kb transgenic mice and IFN-gamma release assays we demonstrate that the NS4.1769 epitope, is generated from natural processing of the NS4 antigen, and presented in the context of the A2/Kb molecules. Interestingly, T cell recognition of the naturally processed form of the NS4.1769 epitope was associated with significant IFN-gamma release, but no direct cytolytic activity. Epitopes of this phenotype might be of interest, in terms of therapy of chronic HCV infection by associating the benefit of localized lymphokine release with low or absent direct cytopathicity.  相似文献   
57.
58.
INTRODUCTION: Blue rubber bleb nevus syndrome (BRBNS) is a rare congenital systemic angiodysplasia with multiple vascular malformations in the skin, gastrointestinal tract and, less often, in other internal organs and the brain. CASE REPORT: A 36-year-old man with past history of BRBNS was admitted to our hospital for progressive dyspnea and fatigue. Primary pulmonary hypertension (PPH) was diagnosed. He then developed acute abdominal pain and dyspnea, dying in a few hours due to sudden cardiac arrest. Postmortem examination demonstrated angiomatous lesions located in the skin, small bowel, heart, lungs, liver and thyroid. The lesions were slightly raised, soft and compressible and microscopically consisted of dilated vascular channels lined by a flattened endothelium. The vascular wall was formed by several layers of smooth muscle cells, intermixed with abundant aggregates of elastic lamellae and thin collagen fibers. Luminal thrombi were a frequent finding. In the small bowel, we identified the presence of an abnormally large artery directly opening into a thin-walled venous channel. The most striking finding in the lungs was the presence of thrombi of varying age in the lumen of segmental and elastic arteries, as well as muscular arteries and arterioles. Severe medial hypertrophy of muscular arteries and muscolarization of arterioles were also present. Intimal proliferative lesions and plexiform lesions were never observed. CONCLUSION: The pulmonary findings are consistent with recurrent thromboembolic events from shunts in the visceral lesions. To our knowledge, this is the first report of BRBNS with visceral arterovenous (AV) fistulae complicated by thromboembolic pulmonary hypertension (PH).  相似文献   
59.
To increase the likelihood of finding genetic variation conferring liability to eating disorders, we measured over 100 attributes thought to be related to liability to eating disorders on affected individuals from multiplex families and two cohorts: one recruited through a proband with anorexia nervosa (AN; AN cohort); the other recruited through a proband with bulimia nervosa (BN; BN cohort). By a multilayer decision process based on expert evaluation and statistical analysis, six traits were selected for linkage analysis (1): obsessionality (OBS), age at menarche (MENAR), and anxiety (ANX) for quantitative trait locus (QTL) linkage analysis; and lifetime minimum body mass index (BMI), concern over mistakes (CM), and food-related obsessions (OBF) for covariate-based linkage analysis. The BN cohort produced the largest linkage signals: for QTL linkage analysis, four suggestive signals: (for MENAR, at 10p13; for ANX, at 1q31.1, 4q35.2, and 8q13.1); for covariate-based linkage analyses, both significant and suggestive linkages (for BMI, one significant [4q21.1] and three suggestive [3p23, 10p13, 5p15.3]; for CM, two significant [16p13.3, 14q21.1] and three suggestive [4p15.33, 8q11.23, 10p11.21]; and for OBF, one significant [14q21.1] and five suggestive [4p16.1, 10p13.1, 8q11.23, 16p13.3, 18p11.31]). Results from the AN cohort were far less compelling: for QTL linkage analysis, two suggestive signals (for OBS at 6q21 and for ANX at 9p21.3); for covariate-based linkage analysis, five suggestive signals (for BMI at 4q13.1, for CM at 11p11.2 and 17q25.1, and for OBF at 17q25.1 and 15q26.2). Overlap between the two cohorts was minimal for substantial linkage signals.  相似文献   
60.
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