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2.
We have studied 25 thymomas by both immunohistochemistry and in situ hybridization for the presence of growth hormone (GH)-producing cells. Our results indicate that 1) GH-immunoreactive cells were present in 13 of 17 thymomas of cortical and predominantly cortical type but not in medullary (spindled) thymomas (n = 3) or low- to high-grade thymic carcinomas (n = 5), 2) GH-positive cells were mainly located at the periphery of the neoplastic lobules, at the periphery of the perivascular spaces and in the areas of medullary differentiation, 3) cells containing GH mRNA appeared at locations similar to those of GH-immunoreactive cells, and 4) GH-immunoreactive material was present only in the epithelial cell component as revealed by immunoelectron microscopy. In conclusion, this paper demonstrates the occurrence of GH-producing cells in noncarcinoid thymic tumors. The relevance of GH in thymoma cell biology requires additional investigations.  相似文献   
3.
The inhibitory effect of glucocorticoids on the in vitro response to phytohaemagglutinin of the residual circulating T lymphocytes in renal transplant patients during maintenance immunosuppressive therapy with glucocorticosteroids and azathioprine has been investigated. As in normal subjects, the steroid-induced inhibition of transplanted patients' lymphocyte response was inversely correlated with the mitogen concentration used. On the other hand, the response of the various lymphocyte preparations from transplanted patients appeared less inhibited by steroids than the corresponding preparations from normal subjects. The addition to the culture of the adherent cell product interleukin 1 was effective in removing to a similar extent the steroid inhibitory effect on lymphocytes from normal and transplanted subjects. Thus, the lesser inhibitory effect of glucocorticoids on transplanted patient lymphocytes could be explained by the higher percentages of monocytes present in all peripheral blood mononuclear cell preparations. These results suggest that during immunosuppressive therapy with glucocorticoids and azathioprine the residual circulating lymphocytes have a responsiveness to in vitro dexamethasone suppression similar to that of normal peripheral blood lymphocytes.  相似文献   
4.
To study the relevance of γδ T cells in multiple sclerosis (MS) we analyzed the T cell receptor (TCR) γδ repertoire and the antigen reactivity of γδ clones isolated from cerebrospinal fluid (CSF). In T cell cultures derived from CSF we found an increased percentage of Vδ1+ cells as compared to peripheral blood of the same donors. Phenotypic analysis of cells from MS CSF with Vγ- and Vγ-specific monoclonal antibodies (mAb) showed that the Vγ1 chain is most frequently associated with γ chains belonging to the VγI family. Sequence analysis of TCR genes revealed heterogeneity of junctional regions in both δ and γ genes indicating polyclonal expansion. γδ clones were established and some recognized glioblastoma, astrocytoma or monocytic cell lines. Stimulation with these targets induced serine esterase release and lymphokine expression characteristic of the TH0-like phenotype. Remarkably, these tumor-reactive γδ cells were not detected in the peripheral blood using PCR oligotyping, but were found in other CSF lines independently established from the same MS patient. Altogether, these results demonstrate that in the CSF there is a skewed TCR γδ repertoire and suggest that γδ cells reacting against brain-derived antigens might have been locally expanded.  相似文献   
5.
S-100 antigen containing cells with dendritic features, recognisable by morphological and immunohistochemical criteria as belonging to the Langerhans' or interdigitating reticulum cell type, have been found in undifferentiated nasopharyngeal carcinoma. The presence of these cells, which have a special function of antigen presentation in immune responses, may be involved in a possible modulation of nasopharyngeal carcinoma associated Epstein-Barr virus infection and host-tumour interactions.  相似文献   
6.
Summary The immunohistochemical distribution of S-100 protein in patients with Down's syndrome was investigated as part of a study aimed at ascertaining a possible involvement in the syndrome (trisomy 21) of this protein, which has recently been shown to be coded in chromosome 21. No appreciable differences in the cell distribution of the antigen could be observed between patients with Down's syndrome and normal subjects. The possibility of an overexpression or abnormal expression of the molecule as a consequence of chromosome 21 triplication, not detectable by immunocytochemical methods alone, remains to be investigated.Supported in part by grants from Consiglio Nazionale delle Ricerche and Ministero della Pubblica Istruzione to F. M. and L. L.  相似文献   
7.
Screening patients admitted to a rehabilitation center has become important. Actually, co-existing diseases are not very often evaluated and their importance is underestimated. At our department 166 consecutive patients were enrolled. The Cumulative Illness Rating Scale (CIRS) appeared to be the most suitable for these cases. In this series, stroke patients presented with higher severity and higher comorbidity than the hip fracture patients. The hip fracture cases were older but the stroke cases had higher severity and comorbidity. Comorbidity, also, showed a significant negative correlation with FIM in the stroke patients. These data show that severe comorbid conditions influence the functional autonomy. Severity and comorbidity were correlated both in the hip fracture and stroke cases. A review of geriatric literature demonstrates lower values in patients in rehabilitation. The difference is due to our accurate selection of patients at admission, where general health conditions are considered. In conclusion, the CIRS should be used as a method for selecting patients at admission and as a prognostic index for improvement at discharge. The CIRS, however, has some inconveniences and amelioration is necessary, such as the inclusion of a double testing (admission-discharge), psychiatric disturbances and a new item for skin alone. The Severity Index was higher in women, who were older than men, whereas, comorbidity was the same. In the patients suffering from hip fracture, the age was higher in women, but dependence, severity and comorbidity did not statistically differ between the groups.  相似文献   
8.
Hypothalamitis: a diagnostic and therapeutic challenge   总被引:1,自引:0,他引:1  
To report an unusual case of biopsy-proven autoimmune hypophysitis with predominant hypothalamic involvement associated with empty sella, panhypopituitarism, visual disturbances and antipituitary antibodies positivity. We present the history, physical findings, hormonal assay results, imaging, surgical findings and pathology at presentation, together with a 2-year follow-up. A literature review on the hypothalamic involvement of autoimmune hypophysitis with empty sella was performed. A 48-year-old woman presented with polyuria, polydipsia, asthenia, diarrhea and vomiting. The magnetic resonance imaging (MRI) revealed a clear suprasellar (hypothalamic) mass, while the pituitary gland appeared atrophic. Hormonal testing showed panhypopituitarism and hyperprolactinemia; visual field examination was normal. Pituitary serum antibodies were positive. Two months later an MRI documented a mild increase of the lesion. The patient underwent biopsy of the lesion via a transsphenoidal approach. Histological diagnosis was lymphocytic “hypothalamitis”. Despite 6 months of corticosteroid therapy, the patient developed bitemporal hemianopia and blurred vision, without radiological evidence of chiasm compression, suggesting autoimmune optic neuritis with uveitis. Immunosuppressive treatment with azathioprine was then instituted. Two months later, an MRI documented a striking reduction of the hypothalamic lesion and visual field examination showed a significant improvement. The lesion is stable at the 2-year follow-up. For the first time we demonstrated that “hypothalamitis” might be the possible evolution of an autoimmune hypophysitis, resulting in pituitary atrophy, secondary empty sella and panhypopituitarism. Although steroid treatment is advisable as a first line therapy, immunosuppressive therapy with azathioprine might be necessary to achieve disease control.  相似文献   
9.
Pleomorphic xanthoastrocytoma (PXA) is a rare tumor with good prognosis after surgery. Few cases of anaplastic PXA (either de novo or secondary to transformation of a recurrent low grade PXA) have been reported. Moreover, primary anaplastic PXA with dissemination at diagnosis has been described only in two patients, to our knowledge. We report the first case of primary multicentric anaplastic PXA and discuss its atypical features and the pertinent literature.  相似文献   
10.
The aim of the study was to evaluate serum acid-labile subunit (ALS) concentrations and their relationship with other parameters of the human ternary IGF-I-binding protein (IGFBP) complex in girls with central precocious puberty (CPP) before and after pharmacological arrest of puberty. We studied serum ALS, free IGF-I, total IGF-I, IGFBP-3 levels and IGFBP-3 protease activity in 13 girls, aged 1.6-7.8 yr (mean, 5.9 +/- 2.2), diagnosed as having CPP before and after 6 and 12 months of GnRH analog (GnRHa) therapy. The ALS SD score before treatment was high (1.4 +/- 0.72) and decreased significantly after 6 and 12 months of GnRHa therapy [0.4 +/- 0.54 (P < 0.01) and -0.4 +/- 0.61 (P < 0.01), respectively]. Serum IGF-I and IGFBP-3 were also increased before treatment, but both of these factors remained elevated after 6 and 12 months of GnRH-A therapy [IGF-I SD score, 3.20 +/- 1.64, 2.92 +/- 1.82, and 3.68 +/- 1.94 (P = NS), respectively; IGFBP-3 SD score, 1.02 +/- 0.53, 0.94 +/- 0.68, and 1.22 +/- 0.87 (P = NS), respectively]. Serum free IGF-I levels and IGFBP-3 proteolytic activity did not vary significantly from their pretreatment values during GnRHa therapy. In conclusion, serum ALS levels were elevated in girls with CPP and decreased significantly during the first year of GnRHa therapy. Serum IGF-I and IGFBP-3 levels were also increased before therapy, but their levels were not influenced by treatment. The ALS decrease seems to be the sole GH-dependent factor that parallels the decreases in steroid levels and growth velocity during GnRHa therapy.  相似文献   
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