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排序方式: 共有2308条查询结果,搜索用时 15 毫秒
31.
Yuji Ohtsuki Bruce Mackay Jae Y. Ro Alberto G. Ayala 《Medical Electron Microscopy》1998,31(4):222-225
We report ribosome-lamella complexes (RLC) in cancer cells of transitional cell carcinoma (TCC) of the prostate in a 52-year-old Caucasian man. Histopathologically, cancer cells were proliferated in various-sized nests, mostly associated with central necrosis. Some invaded into the surrounding normal glandular space and the stroma, with occasional lymphatic invasion. Fine structural study of cancer cells revealed that cross-sectioned RLC as well as densely aggregated ribosomes were detected in their cytoplasm, situated close to, but not directly connected with, dilated rough endoplasmic reticulum. These were composed of a concentric alternative arrangement of both lamellae and ribosomes. In the central and surrounding parts of the RLC, ribosomes were observed, revealing a smooth transition to the ribosomal component of RLC in size and shape. The presence of both RLC and dense aggregation of ribosomes close to the rough endoplasmic reticulum suggests that their functions might be related to specific or aberrant protein synthesis under unknown conditions. Although RLC have been often reported in hematopoietic malignancies, their occurrence in the malignant epithelial component has been only reported in a case of pulmonary adenocarcinoma. This is the first report of RLC in TCC in the literature. 相似文献
32.
Adenosine decreases post-ischaemic cardiac TNF-alpha production: anti-inflammatory implications for preconditioning and transplantation. 总被引:1,自引:0,他引:1
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D R Meldrum B S Cain J C Cleveland Jr X Meng A Ayala A Banerjee A H Harken 《Immunology》1997,92(4):472-477
Tumour necrosis factor-alpha (TNF-alpha) is an autocrine contributor to myocardial dysfunction and cardiomyocyte death in ischaemia-reperfusion injury (I/R), sepsis, chronic heart failure and cardiac allograft rejection. Cardiac resident macrophages, infiltrating leucocytes, and cardiomyocytes themselves produce TNF-alpha. Although adenosine reduces macrophage TNF-alpha production and protects myocardium against I/R, it remains unknown whether I/R induces an increase in cardiac TNF-alpha in a crystalloid-perfused model (in the absence of blood), and, whether adenosine decreases cardiac TNF-alpha and protects function after I/R. To study this, isolated rat hearts were crystalloid-perfused using the Langendorff method and subjected to I/R, with or without adenosine pretreatment. Post-ischaemic cardiac TNF-alpha (enzyme-linked immunosorbent assay and bioassay) and function were determined (Langendorff). I/R increased cardiac TNF-alpha and impaired myocardial function. Adenosine decreased cardiac TNF-alpha and improved post-ischaemic functional recovery. This study demonstrates that: first, I/R induces an increase in cardiac tissue TNF-alpha in a crystalloid-perfused model: second, adenosine decreases cardiac TNF-alpha and improves post-ischaemic myocardial function; third, decreased cardiac TNF-alpha may represent a mechanism by which adenosine protects myocardium; and fourth, adenosine-induced suppression of cardiac TNF-alpha may provide an anti-inflammatory link to preconditioning and have implications for cardiac allograft preservation. 相似文献
33.
Ethical considerations for enzyme replacement therapy in neuronopathic Gaucher disease 总被引:1,自引:0,他引:1
Elstein D, Abrahamov A, Zimran A. Ethical considerations for enzyme replacement therapy in neuronopathic Gaucher disease. Clin Genet 1998: 54: 179–184. 0 Munksgaard, 1998
Enzyme replacement therapy for Gaucher diseases, the most prevalent lysosmal storage disease, was originally approved by the FDA for type I patients and has proven to be both safe and effective in reducing hepatosplenomegaly and improving the hematological parameters. However, the use of enzyme treatment in both neuronopathic forms has heretofore been on an investigational or trial basis, with reports of progression of neurological deterioration even at very high doses. To date, there are no guidelines for clinicians with regard to enzyme replacement therapy in the neuronopathic forms of metabolic diseases. Herein, we discuss strategies derived from the literature ub-his treatment of very premature babies and from the Jewish Halachic point of view. In conclusion, we describe recommendations for the ethical treatment and/or withdrawal of treatment. as well as practical guidelines for dosage regimens, in children with neuronopathic Gaucher disease. 相似文献
Enzyme replacement therapy for Gaucher diseases, the most prevalent lysosmal storage disease, was originally approved by the FDA for type I patients and has proven to be both safe and effective in reducing hepatosplenomegaly and improving the hematological parameters. However, the use of enzyme treatment in both neuronopathic forms has heretofore been on an investigational or trial basis, with reports of progression of neurological deterioration even at very high doses. To date, there are no guidelines for clinicians with regard to enzyme replacement therapy in the neuronopathic forms of metabolic diseases. Herein, we discuss strategies derived from the literature ub-his treatment of very premature babies and from the Jewish Halachic point of view. In conclusion, we describe recommendations for the ethical treatment and/or withdrawal of treatment. as well as practical guidelines for dosage regimens, in children with neuronopathic Gaucher disease. 相似文献
34.
Myxoid leiomyosarcoma of the ovary: Analysis of three cases 总被引:2,自引:0,他引:2
Francisco F. Nogales MD Alberto Ayala MD Isabel Ruiz-Avila MD Juan J. Sirvent MD 《Human pathology》1991,22(12):1268-1273
The first three cases of myxoid leiomyosarcoma occurring in the ovary are reported. Two cases in stage III were found in postmenopausal patients and a further case was found in stage I in a 32-year-old. All masses were large and gelatinous with cystic change, necrosis, and hemorrhage, but both uteri and ligaments and contralateral adnexa appeared normal. Microscopically, the tumors showed a predominantly reticular meshwork of elongated cells surrounded by abundant basophilic material. While electron microscopy proved inconclusive due to nondifferentiation, the use of monoclonal antibodies against smooth muscle actin demonstrated a smooth muscle type of differentiation. The differential diagnosis of this rare ovarian condition includes other myxoid ovarian lesions, such as ovarian edema, myxoma, endodermal sinus tumors, and the sarcomatous component of malignant mixed müllerian tumor and carcinosarcoma, as well as lymphovascular tumors. Since mitotic count due to decreased cellular density is unusually low in myxoid leiomyosarcoma, capsular rupture and clinical stage seem to be more reliable prognostic markers. The highly aggressive behavior of myxoid leiomyosarcoma parallels that of typical ovarian leiomyosarcoma. Two of the three patients in this series died of tumor at 13 and 24 months after diagnosis; the other patient is free of disease at 3 years after diagnosis. 相似文献
35.
We have shown that immune cells from septic mice exhibit a suppressed response to exogenous stimuli in vitro. The suppressors of the cytokine signaling (SOCS) family are proteins that block intracellular signaling and can be induced by inflammatory mediators. Therefore, we hypothesized that SOCS-3 is up-regulated in immune cells in response to a septic challenge induced by cecal ligation and puncture (CLP). Mice were subjected to CLP or sham-CLP, and 2-48 h later, the blood, thymus, spleen, lung, and peritoneal leukocytes were harvested and examined. SOCS-3 was undetectable in thymocytes or blood leukocytes. In contrast, SOCS-3 was up-regulated in the spleen, lung, and peritoneal leukocytes in a time-dependent manner. Further examination revealed that only the macrophages and neutrophils expressed SOCS-3. These data suggest that cytokines and bacterial toxins present during sepsis have the ability to suppress the cytokine and/or lipopolysaccharide response and the function of immune cells by up-regulating SOCS-3. 相似文献
36.
Regulation of hepatocyte activator inhibitor-1 expression by androgen and oncogenic transformation in the prostate
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Knudsen BS Lucas JM Fazli L Hawley S Falcon S Coleman IM Martin DB Xu C True LD Gleave ME Nelson PS Ayala GE 《The American journal of pathology》2005,167(1):255-266
Hepatocyte activator inhibitor-1 (HAI-1) is a transmembrane serine protease inhibitor that regulates the conversion of latent to active hepatocyte growth factor (HGF). Studies supporting a role for the HGF pathway in prostate carcinogenesis prompted an analysis of HAI-1 expression in the prostate. Here we analyze the regulation of HAI-1 expression by androgen, oncogenic transformation, and cancer progression. Immunohistochemical analysis revealed that HAI-1 expression was restricted to prostate epithelium, where staining occurred primarily in basal and atrophic luminal epithelial cells. Compared to normal glands, HAI-1 expression was significantly increased in localized prostate cancer and was present in most prostate cancer metastases. HAI-1 protein expression levels were sensitive to androgen in normal epithelium but not in cancer. Although androgen did not increase HAI-1 protein expression levels in LNCaP cells, it decreased HAI-1 surface expression, consistent with previous data from our group (Martin DB, Gifford DR, Wright ME, Keller A, Yi E, Goodlett DR, Aebersold R, Nelson PS: Quantitative proteomic analysis of proteins released by neoplastic prostate epithelium. Cancer Res 2004, 64:347-355). HAI-1 overexpression in cancer was predictive of prostate-specific antigen recurrence (relative risk, 1.24). These results suggest that HAI-1 regulates the HGF Met axis on prostate epithelial cells and influences HGF mediated tumor invasion and metastasis. 相似文献
37.
Four tumors with the clinical and light microscopic features of Ewing's sarcoma contained cells that possessed to varying degrees ultrastructural features suggestive of neuroblastoma. These neoplasms were considered to be Ewing's sarcoma of bone by radiologic examination and on clinical grounds, and light microscopy was consistent with the diagnosis in every case. It is suggested that the ultrastructural morphology of Ewing's sarcoma is broader than had been supposed and that the presence of dendritic processes in a small cell tumor of bone should not exclude the diagnosis of Ewing's sarcoma. 相似文献
38.
We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature. 相似文献
39.
G C Friedman R W Hartwick J Y Ro G Y Saleh J J Tarrand A G Ayala 《American journal of clinical pathology》1991,96(3):368-372
Most reported cases of allergic sinusitis have been attributed to Aspergillus, based on the morphologic features of the organisms in tissue sections. However, in most cases, cultures have not been done. This is a report of three cases of non-Aspergillus allergic fungal sinusitis. The patients' ages were 11, 16, and 43; two were male and one was female. Histopathologic study disclosed fungal organisms resembling Aspergillus. However, cultures of these patients' nasal secretions grew Drechslera, Exserohilum, and Bipolaris fungal organisms. The non-Aspergillus nature of these infections was further supported by positive Fontana-Masson melanin staining. The authors conclude that allergic fungal sinusitis most likely results from non- Aspergillus organisms. For definitive fungal identification, tissue culture is mandatory. When tissue is not cultured or no organisms grow, a Fontana-Masson stain can be a useful adjunct in fungal identification. 相似文献
40.
Control of primary osteosarcoma with chemotherapy 总被引:1,自引:0,他引:1
N Jaffe R Robertson Y Takaue A Cangir S Wallace H Carrasco F Eftekhari A Ayala A Wang 《Cancer》1985,56(3):461-466
High-dose methotrexate with citrovorum factor "rescue" (MTX-CF) produced an apparent complete response of the primary tumor in three patients with osteosarcoma. The response was sustained with MTX-CF, intra-arterial cis-diamminedichloroplatinum II (CDP) and Adriamycin (doxorubicin) for 18 months. Treatment was then electively discontinued. Local recurrence occurred in two patients, 6 and 4 months later, respectively. MTX-CF was reinstated and a complete response was again achieved in one patient. This has been maintained for 15+ months with MTX-CF and intra-arterial CDP administered for 13 of the 15+ months. Reinduction with MTX-CF failed in the second relapsed patient but an apparent remission was again achieved with radiation and intra-arterial CDP. This has been maintained with intravenous CDP, cyclophosphamide and phenylalanine mustard for 14+ months. A complete response in the primary tumor was still present in the nonrelapsed patient, 42 months from diagnosis. All patients have remained free of pulmonary metastases, 40+ to 42+ months from diagnosis. 相似文献