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31.
A 56-year-old female with congestive heart failure was transferred to our institution. Aortography demonstrated aortic valve stenosis (AS) with a congenitally bicuspid valve and dilatation of the ascending aorta. Preoperative coronary angiography showed a left single coronary artery. Replacement of the aortic valve and ascending aorta was performed. She had an uneventful postoperative course. We report the case of aortic bicuspid valve stenosis with single coronary artery as an extremely rare congenital cardiac anomaly combination.  相似文献   
32.
A case of non-Hodgkin's lymphoma showed a phenotypic and genotypic cell lineage switch twice during nine years of his clinical history; first, T-cell type, pleomorphic small cell lymphoma developed, followed by B-cell type, diffuse centroblastic/centrocytic lymphoma, and finally T-zone lymphoma without follicles again developed, from which AST-1 cultured cell line was established. Karyotype analysis demonstrated a shared abnormal chromosome, der(1)t(1;?)(p36;?), among the first relapsed B-cell tumor, the second relapsed T-cell tumor and AST-1 cell line. Furthermore, T-cell receptor (TCR) γ gene rearrangement bands of the same size were observed in the first relapsed B-cell tumor and the second relapsed T-cell tumor as well as AST-1 cell line. These results suggested that both relapsed tumors of different cell lineages are derived from a common malignant clone, presumably a committed lymphoid stem cell. A unique translocation, t(2;14)(q37;q11.2), which may involve TCR δ/α gene complex, was observed in the second relapsed tumor and AST-1 cells. To attempt to isolate the breakpoint of this translocation, the configuration of TCR δ/α gene complex was studied. The result showed that two rearrangements of TCR α gene detected with Jα probes were the products of the normal TCR rearrangement process, and were not involved in the translocation at this region. This patient, together with the AST-1 cell line, provided us a unique opportunity to study the development and clonal evolution of malignant lymphoma.  相似文献   
33.
In this study, we analyzed T cell receptor (TCR) gene rearrangements in tumor-infiltrating lymphocytes (TIL) freshly obtained from 15 patients with head and neck cancer using the reversely transcribed polymerase chain reaction (RT-PCR) method. These TILs showed preferential expression of Vα10, Vα8 and Vα1, detected in 13 (87%), 11 (73%), and 9 cases (60%), respectively. The TCRVβ gene revealed diversity without preferential usage. The head and neck region is exposed to bacteria and viruses, so it is possible that the tumor site can become infected and accumulate T cells involved in infection and inflammation. Therefore, we also investigated TCR gene usage in T cells infiltrating in chronic sinusitis mucosa to address the question of whether the Vα1, Vα8, and Vα10 subfamilies are characteristic in TIL from squamous cell carcinoma of head and neck. TCR Vα10 gene usage was also the most common in Vα segment in T cells infiltrating the sinus mucosa, but Vα and Vα8 were not detected in the T cells in sinusitis. These results indicate that the Vα10 subfamily, the preferred T cell population in both TIL and T cells in inflammatory disease, might he involved mainly in inflammation or infection. On the other hand, Vα1 and Vα8 appear to be relatively specific populations for antitumor immunity in head and neck cancer.  相似文献   
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The effects of glucocorticoids on the proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid in relation to humoral and cellular immunity were studied in 56 patients with steroid-dependent intractable asthma. To analyze the mechanism responsible for reduced numbers of BAL lymphocytes, we divided the subjects into 4 groups according to their BAL lymphocyte proportions: 0—4.9%, 5.0-9.9%, 10.0-14.9%, and 15.0-20.0%. Serum IgG levels and the peripheral lymphocyte count were significantly reduced in patients with a low proportion of BAL lymphocytes (less than 9.9%) than in those with more than 10% BAL lymphocytes. Delayed cutaneous reactivity to purified protein derivative was suppressed in patients with a low proportion of BAL lymphocytes (less than 4.9%). The mean proportion of BAL neutrophils tended to increase as the proportion of BAL lymphocytes decreased. These results show that the reduction in BAL lymphocytes produced by glucocorticoids is associated with suppressed humoral and cellular immunity, and that under such conditions the proportion of BAL neutrophils increases.  相似文献   
37.
The antagonistic effects of MDL73005EF and tamsulosin and partial agonists clonidine and tizanidine at rat thoracic aorta and rabbit iliac artery alpha1-adrenoceptors were investigated in this study. Selective alpha1-adrenoceptor antagonists MDL73005EF and tamsulosin dose-dependently shifted the concentration-response curves for noradrenaline to the right. Schild plots of the results obtained from the inhibition by MDL73005EF (pA2 8.30 +/- 0.04) and tamsulosin (pA2 10.51 +/- 0.06) of noradrenaline yielded a straight line with a slope of unity in rat thoracic aorta. The slopes of Schild plots obtained from the inhibition by MDL73005EF and tamsulosin of noradrenaline were significantly different from unity in rabbit iliac artery. Schild plots of the results obtained from the inhibition by clonidine and tizanidine of noradrenaline yielded a straight line with a slope of unity in rat thoracic aorta (pA2 7.08 +/- 0.04 and 7.32 +/- 0.04, respectively). These results suggest that alpha1D-adrenoceptors play a significant role in the alpha1-adrenoceptor-agonist-induced contraction of rat thoracic aorta and rabbit iliac artery, and that clonidine and tizanidine interact with the alpha1D-adrenoceptor subtype as competitive antagonists in rat thoracic aorta.  相似文献   
38.
The histogenesis of stromal cells in hemangioblastoma is inconclusive despite a long-term controversy. An immunohistochemical and ultrastructural study was conducted for 17 cases of cerebellar hemangioblastoma. A wide range of immunohistological markers, targeting epithelial, mesenchymal, endothelial and neuroectodermal tissues, was used. In all cases, the microscopic hallmark characterizing hemangioblastomas, that is, lipid-containing stromal cells and a fine capillary network, known as a reticular variant, was noted. Stromal cells showed a variable immunoreactivity for neuroectodermal markers, such as S-100 protein, CD56, CD57, CD99, and neuron-specific enolase. This result, in conjunction with the absence of immunoreactivity for epithelial, mesenchymal, and endothelial markers, likely suggests neuroectodermal differentiation of stromal cells. In three cases, another component, known as a cellular variant, where epithelioid tumor cells were arranged in nests encircled by capillaries and/or in pseudorosette-like structures, was noted. Glial fibrillary acidic protein-immunoreactivity, which was totally absent in cases only showing the reticular pattern, was noted in two of them, suggesting a distinctive sign of glial differentiation in a proportion of hemangioblastomas. Ultrastructurally, microvilli-like projections in intracytoplasmic vacuoles were demonstrated in stromal cells. This result, taken together with the neuroectodermal hypothesis of stromal cells, suggests that hemangioblastomas may occasionally exhibit morphological similarities to ependymomas.  相似文献   
39.
To investigate the effects of polymorphisms in the ATP-binding cassette transporter A1 (ABCA1) gene on the high-density lipoprotein cholesterol (HDL-C) level and the incidence of myocardial infarction (MI), we performed association studies. Sequence analysis identified 14 polymorphisms in the promoter region of ABCA1. After considering linkage disequilibrium, three polymorphisms in the promoter region and 11 polymorphisms from the JSNP database were determined in 1,880 subjects recruited from the Suita Study, representing the general population in Japan. We evaluated the association between the ABCA1 genotype and HDL-C level adjusted not only for standard factors, but also for genetic factors including ApoA1 and ApoE genotypes. Of the 14 polymorphisms tested, the G(–273)C (P=0.0074), C(–297)T (P=0.0195), and IMS-JST071749 (P=0.0093) polymorphisms were significantly associated with the HDL-C level in the Suita population. We could reconfirm that the G(–273)C genotype was influential in another set of subjects (P=0.0310, n=743). However, the distribution of the ABCA1 G(–273)C genotype in subjects with MI (n=598) was not different from that in the control population (n=801). These results indicate that ABCA1 G(–273)C has a significant effect on the HDL-C level in the general Japanese population, but not on the incidence of MI.  相似文献   
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