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排序方式: 共有9379条查询结果,搜索用时 31 毫秒
31.
An orthotopic metastatic prostate cancer model in SCID mice via grafting of a transplantable human prostate tumor line 总被引:2,自引:0,他引:2
Wang Y Xue H Cutz JC Bayani J Mawji NR Chen WG Goetz LJ Hayward SW Sadar MD Gilks CB Gout PW Squire JA Cunha GR Wang YZ 《Laboratory investigation; a journal of technical methods and pathology》2005,85(11):1392-1404
Metastasis is the major cause of prostate cancer deaths and there is a need for clinically relevant in vivo models allowing elucidation of molecular and cellular mechanisms underlying metastatic behavior. Here we describe the development of a new in vivo model system for metastatic prostate cancer. Pieces of prostate cancer tissue from a patient were grafted in testosterone-supplemented male NOD-SCID mice at the subrenal capsule graft site permitting high tumor take rates. After five serial transplantations, the tumor tissues were grafted into mouse prostates. Resulting tumors and suspected metastatic lesions were subjected to histopathological and immunohistochemical analysis. Samples of metastatic tissue were regrafted in mouse anterior prostates and their growth and spread examined, leading to isolation from lymph nodes of a metastatic subline, PCa1-met. Orthotopic grafting of PCa1-met tissue in 47 hosts led in all cases to metastases to multiple organs (lymph nodes, lung, liver, kidney, spleen and, notably, bone). Histopathological analysis showed strong similarity between orthotopic grafts and their metastases. The latter were of human origin as indicated by immunostaining using antibodies against human mitochondria, androgen receptor, prostate-specific antigen and Ki-67. Spectral karyotyping showed few chromosomal alterations in the PCa1-met subline. This study indicates that transplantable subrenal capsule xenografts of human prostate cancer tissue in NOD-SCID mice can, as distinct from primary cancer tissue, be successfully grown in the orthotopic site. Orthotopic xenografts of the transplantable tumor lines and metastatic sublines can be used for studying various aspects of metastatic prostate cancer, including metastasis to bone. 相似文献
32.
Effects of omalizumab and budesonide on markers of inflammation in human bronchial epithelial cells.
Yu-Ching Huang Bartlomiej Leyko Marianne Frieri 《Annals of allergy, asthma & immunology》2005,95(5):443-451
BACKGROUND: Many patients with asthma have an IgE-mediated allergic component to the disease. Omalizumab, a monoclonal anti-IgE antibody, has demonstrated clinical efficacy in patients with allergic asthma. The effects of omalizumab on inflammation in asthma are not completely understood. OBJECTIVES: To evaluate the effects of omalizumab on allergen- and growth factor-stimulated proinflammatory cytokine and nitric oxide (NO) production in human bronchial epithelial cells (BECs) and to compare them to the effects of budesonide, a corticosteroid with known anti-inflammatory properties. METHODS: Human BECs were stimulated in duplicate with interleukin 1beta (IL-1beta), 100 U/mL; ragweed, 10 microg/mL; dust mite, 1000 AU; and epithelial growth factor, 40 ng/mL; and either 10(-7) M budesonide or 0.1 microg/mL of omalizumab in a 4% dust mite atopic serum medium for 6 and 24 hours in 5% carbon dioxide at 37 degrees C. Tumor necrosis factor alpha and transforming growth factor betaexpression and production and IL-4, IL-13, and NO production were assayed using gene-specific messenger RNA or sensitive enzyme-linked immunosorbent assays. RESULTS: Omalizumab inhibited the expression and of production proinflammatory cytokines and growth factor in antigen-stimulated BECs at 6 and 24 hours. Production of NO was inhibited at 6 hours and increased at 24 hours by omalizumab and budesonide. CONCLUSIONS: The effects of omalizumab were similar to those of budesonide. These results, consistent with previously reported evidence of anti-inflammatory effects of omalizumab, demonstrate that omalizumab may reduce airway inflammation and probably contributes to decreased airway remodeling in patients with asthma. 相似文献
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Extracts of infective larvae and adults of the trichostrongylid Haemonchus contortus were studied for the presence of carbohydrate moieties. Several different lectin-binding sites were demonstrated in both stages using a panel of nine lectins. The carbohydrate specificity of the lectins used strongly suggests that α-D-mannose, α-D-glucose, and D-N-acetylglucosamine are the most important carbohydrate epitopes present on H. contortus proteins. Thus, N-linked oligosaccharides form the major part of the carbohydrate moieties on these glycoproteins. Treatment with sodium periodate was performed to investigate the immunoreactivity towards the carbohydrate moieties. This treatment resulted in a reduction in the immunoreactivity of these antigens as demonstrated by enzyme-linked immunosorbent assay (ELISA) and immunoblotting, suggesting that a substantial part of the host immune response against H. contortus is directed against the carbohydrate epitopes on the parasite antigens. 相似文献
38.
Tumor Vascularity Is Not a Prognostic Factor for Malignant Melanoma of the Skin 总被引:1,自引:4,他引:1 下载免费PDF全文
Klaus J. Busam Marianne Berwick Karen Blessing Katrin Fandrey Sewon Kang Themis Karaoli Judy Fine Alistair J. Cochran Wain L. White Jason Rivers David E. Elder Duan-Ren Po Wen Bradley H. Heyman Raymond L. Barnhill 《The American journal of pathology》1995,147(4):1049-1056
Tumor vascularity has been proposed as a prognostic indicator for a number of solid tumors. Although a correlation between microvessel number and metastatic behavior has also been suggested for cutaneous melanoma, the small number of cases studied to date allows one to draw only preliminary conclusions. In this study, we have assessed tumor vascularity in cutaneous melanoma by comparing 60 cases of metastasizing and non-metastasizing tumors matched for tumor thickness, age, sex, and anatomic site. Ulex europaeus agglutinin I appeared to be the most suitable vascular marker for this study. Our results indicate that there was no statistically significant difference between the two groups with regard to tumor vascularity. Even after identifying 15 cases of thin (<1.0 mm thick) melanoma, there was no significant difference in the number of microvessels between metastasizing and non-metastasizing tumors. Comparison of patterns of vascular microarchitecture also failed to discriminate between the two groups. Thus, our results indicate that tumor vascularity may not be an independent prognostic factor for cutaneous melanoma. 相似文献
39.
We have developed a transient expression system for the protist Physarum polycephalum based on firefly luciferase. We demonstrate the utility of this system for comparing the activities of different promoters in Physarum amoebae, and also for detecting genetic elements that affect the level of gene expression. This system is likely to facilitate improvements in the stable transformation of this organism. 相似文献
40.
Development and application of a salmonid EST database and cDNA microarray: data mining and interspecific hybridization characteristics 总被引:10,自引:0,他引:10 下载免费PDF全文