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1.
We immunohistochemically analyzed cellular apoptosis susceptibility (CAS) protein expression and compared it with 20q13.2 copy number and the expression of cell cycle-associated proteins retinoblastoma (Rb), cyclin D1, and p53 and prognosis on paraffin-embedded tissue from 69 ovarian carcinomas (OCs). CAS protein reactivity was present in 100%, Rb in 54%, cyclin D1 in 47%, and p53 in 49%. Significant reciprocal correlation was observed between high levels of CAS and histologic type, FIGO (International Federation of Obstetrics and Gynecology) stage III and grade 3, residual tumor (>2 cm), 20q13.2 (ZNF217 gene) amplification (>4 copies in >20% cells), and high expression of cyclin D1 (all P < .05). No association was found between cyclin D1, p53, or Rb levels with clinicopathologic factors. In univariate analysis, residual tumor, FIGO stage and grade, ZNF217 amplification, and CAS levels predicted outcome (all P < .05). In multivariate analysis, stage, grade, amount of residual tumor, and ZNF217 amplification showed independent prognostic value (all P < .05). In OC, alteration of CAS and ZNF217 genes, both located at 20q13, is frequent and relevant prognostically. Cyclin D1, Rb, and p53 seem to have a secondary role.  相似文献   
2.
Ki-ras mutations by denaturing gradient gel electrophoresis (DGGE) and direct sequencing after microdissection. Point mutations at codon 12 were found in 7 of 20 tumours of low malignant potential (LMP) (35%) and in 2 of 6 well-differentiated carcinomas (33%). In contrast, no mutations were detected in the 11 poorly differentiated ovarian carcinoma samples or in the 7 serous cystadenomas. The frequency of Ki-ras mutations in serous ovarian tumours seems to correlate with the malignant potential of the neoplasms. The data favour the hypothesis of a de novo development of poorly differentiated ovarian carcinomas and do not support an evolution from LMP tumours or well-differentiated carcinomas. Received: 8 June 1998/Accepted: 8 October 1998  相似文献   
3.
Summary Between 1978 and 1983 a total of 33 patients with non-Hodgkin's lymphoma (NHL) involving the gastrointestinal tract were seen in our institution. Pathological classification was performed according to Kiel. Low grade NHL was diagnosed in 17, high grade NHL in 16 patients. The most frequent histological entity was lymphoplasmocytoid immunocytoma (11 patients). The most common sites of origin were the stomach (23 patients) and the ileocecal region (6 patients). The majority of patients presented with stage I and II disease (20 of 33 patients). As a rule primary therapy consisted of surgery with curative intent. Most of the patients received additional chemotherapy or radiotherapy. Patients with limited disease and complete tumour resection showed long-term survival from 12+ to 57+ months (mean 32.9+ months). Patients with advanced disease (stage III and IV) and only palliative surgery or with lymphoblastic lymphoma had a probability of survival of less than 12 months.Abbreviations NHL non-Hodgkin's lymphoma - IC lymphoplasmocytoid immunocytoma - CC centrocytic lymphoma - CB/CC centroblastic/centrocytic lymphoma - CB centroblastic lymphoma - IB immunoblastic lymphoma - LB lymphoblastic lymphoma - NWDL nodular well-differentiated lymphocytic lymphoma - NPDL nodular poorly differentiated lymphocytic lymphoma - NM nodular mixed lymphoma - NH nodular histiocytic lymphoma - DWDL diffuse well-differentiated lymphocytic lymphoma - DPDL diffuse poorly differentiated lymphocytic lymphoma - DM diffuse mixed lymphoma - DH diffuse histiocytic lymphoma - DU diffuse undifferentiated lymphoma - CT computerized tomography - GI gastrointestinal  相似文献   
4.
OBJECTIVE: In a prospective multicenter trial, it was our intention to elucidate clinical prognostic factors of seminomas with special reference to the importance of human chorionic gonadotropin (HCG) elevations in histologically pure seminomas. METHODS: Together with 96 participating urological departments in Germany, Austria, and Switzerland, we recruited 803 seminoma patients between 1986 and 1991. Out of 726 evaluable cases, 378 had elevated, while 348 had normal HCG values in the cubital vein. Histology was reviewed by two reference pathologists. HCG levels were determined in local laboratories and in a study laboratory. Standard therapy was defined as radiotherapy in stages I (30 Gy) and IIA/B (36 Gy) to the paraaortal and the ispilateral (stage I) and bilateral (stage IIA/B) iliac lymph nodes; higher stages received polychemotherapy and surgery in case of residual tumor masses. Statistics included chi-square tests, linear Cox regression, and log-rank test. RESULTS: The HCG elevation is associated with a larger tumor mass (primary tumor and/or metastases). HCG-positive and HCG-negative seminomas had no different prognostic outcome after standard therapy. The overall relapse rate of 6% and the survival rate of 98% after 36 months (median) indicate an excellent prognosis. The calculation of the relative risk of developing a relapse discovered only stage of the disease and elevation of the lactate dehydrogenase concentration and its prolonged marker decay as independent prognostic factors for seminomas. A more detailed analysis of the prognostic significance of the stage revealed that the high relapse rate in stage IIB seminomas after radiotherapy (24%) is responsible for this result. CONCLUSIONS: We conclude that HCG-positive seminomas do not represent a special entity. Provided standard therapy is applied, HCG has no influence on the prognosis. Patients with stage IIB disease should be treated with chemotherapy because of the demonstrated higher relapse rate outside the retroperitoneum.  相似文献   
5.
Nitric oxide (NO) has important functions in the regulation of pulmonary smooth muscle tone. In the human lung, published data on the expression and distribution of neuronal nitric oxide synthase (NOS-I) are contradictory. The aim of this study, therefore, was to determine the predominant cells expressing NOS-I in the human lung. Immunofluorescence double staining techniques were applied to normal human lung tissue using established monospecific antibodies directed against NOS-I. Suprisingly, capillary endothelial cells in the alveolar septa were identified as the major sites of NOS-I expression. Neither alveolar nor bronchiolar epithelium, nor the alveolar macrophages, expressed NOS-I. These results indicate that the predominant sites of NOS-I expression in the human lung are confined to non-neuronal, i.e. capillary endothelial cells and suggest a role for NO in the regulation of pulmonary endothelial cell permeability.  相似文献   
6.
H Yamaguchi  H Weidenbach  H Lührs  M M Lerch  G Dickneite    G Adler 《Gut》1997,40(4):531-535
BACKGROUND: Patients with severe acute pancreatitis die of complications closely related to the systemic activation of protease cascades. AIM: To examine the effects of human C1 esterase inhibitor (C1 INH) and antithrombin III (AT III) on two experimental models of acute pancreatitis. METHODS: Oedematous pancreatitis was induced by continuous intravenous infusion of caerulein and haemorrhagic pancreatitis by retrograde injection of sodium taurocholate into the biliopancreatic duct. C1 INH and AT III were given intravenously, either before or after the induction of pancreatitis. Treatment with C1 INH and AT III had no beneficial effect on oedematous pancreatitis. On the other hand, combined C1 INH and AT III therapy improved the survival in haemorrhagic pancreatitis compared with treatment with human serum albumin. This reduction in mortality was found regardless of whether the treatment was given prophylactically or therapeutically. CONCLUSIONS: Treatment with C1 INH and AT III represents a promising therapeutic concept for patients with severe haemorrhagic pancreatitis.  相似文献   
7.
Highly pathogenic avian influenza viruses of subtype H5N1 sporadically cause severe disease in humans and involve the risk of inducing a pandemic by gaining the ability for human-to-human transmission. In naïve poultry, primarily gallinaceous birds, the virus induces fatal disease and the used inactivated vaccines occasionally are unable to provide efficient and early onset of protection. Therefore, optimized vaccines must be developed and evaluated in model systems. In our study, we tested a novel H5 neuraminidase-deleted influenza A virus variant to analyze the induction of a very early onset of immunity. Ferrets, mice and chickens were each immunized with a single vaccine dose seven, three and one day before lethal challenge infection, respectively. Sound protection was conferred in 100% of animals immunized seven days prior to challenge infection. In these animals, no clinical signs were observed, and no challenge virus RNA was detected by real-time RT-PCR analyses of swabs, nasal washings, and organ samples. Moreover, the attenuated modified-live virus variant protected all chickens, mice, and ferrets as early as three days after vaccination against severe clinical signs. Chickens and ferrets developed hemagglutinin-specific antibodies after seven days, but no neuraminidase-specific antibodies, making this kind of neuraminidase-negative strain suitable for the DIVA (“differentiating vaccinated from infected animals”) strategy.  相似文献   
8.
Prolongation of allograft survival in ccr7-deficient mice   总被引:4,自引:0,他引:4  
BACKGROUND: Lymphocyte homing to secondary lymphoid organs is thought to be required for initiation of the alloreactive immune response. Because CCR7 is the essential chemokine receptor responsible for lymphocyte and dendritic cell homing to secondary lymphoid organs, allograft survival was analyzed in CCR7-deficient (CCR7) mice. METHODS: Heterotopic heart and skin allotransplantation was performed in CCR7 and wild-type (WT) recipients. Graft survival was monitored daily. Grafts and draining lymph nodes were analyzed by immunohistology and flow cytometry at different time points. Groups of mice were splenectomized at the day of allotransplantation. RESULTS: A significant though modest prolongation of allograft survival in CCR7 recipients was observed for heart grafts (WT, 7.3 +/- 0.5 days; CCR7, 10.7 +/- 2.8 days) and skin grafts (WT, 8.9 +/- 0.9 days; CCR7, 12.3 +/- 0.9 days). This was accompanied by a delay in the cellular infiltration of allografts. T-cell accumulation and expansion in the draining lymph nodes in CCR7 recipients was severely impaired. Splenectomy had only a moderate prolongation effect on allograft survival in CCR7 mice. CONCLUSIONS: These results suggest that CCR7-dependent processes support allograft rejection yet are dispensable for the rejection response.  相似文献   
9.
BACKGROUND: Currently no serological marker for the monitoring of uveal melanoma and its metastases is available. The novel tumor associated antigen Melanoma inhibitory activity (MIA) is expressed in the uveal melanoma and it's metastatic lesions. METHOD: We report about the serum samples of 38 patients with uveal melanomas. 4 of these patients had overt metastatic disease. A nonradioactive one step ELISA was used to quantify the MIA serum levels. RESULTS: In the 34 patients without overt metastatic disease the serum concentration of MIA was mean (+/- 1 SD) 3.6 +/- 1.0 ng/ml. In the 4 patients with overt metastatic disease the serum concentration of MIA was mean (+/- 1 SD) 27.7 +/- 3.0 ng/ml. The difference was statistically highly significant (student t test: p = 0.0001). CONCLUSION: MIA is expressed in primary and metastatic lesions of uveal melanomas. The elevation of MIA serum levels in patients with metastatic disease from melanomas suggests a promising role as a serum marker for monitoring patients with uveal melanoma.  相似文献   
10.
Lipoxygenase metabolites of arachidonic acid can act as growth promoting factors for various cancer cell lines. Here we demonstrate that the 5-lipoxygenase inhibitor nordihydroguaiaretic acid potently inhibits anchorage-independent growth of human pancreatic and cervical cancer cells in soft agar and delays growth of pancreatic and cervical tumours established in athymic mice. Furthermore, nordihydroguaiaretic acid induces apoptosis of these cancer cells in vitro and in vivo. Potential mechanisms mediating these effects of nordihydroguaiaretic acid were examined. Nordihydroguaiaretic acid had no inhibitory effect on growth and survival signals such as tyrosine phosphorylation of the epidermal growth factor receptor or basal and growth factor-stimulated activities of extracellular signal-regulated kinase 1/2, p70(s6k) and AKT but selectively inhibited expression of cyclin D1 in the cancer cells. In addition, treatment with nordihydroguaiaretic acid lead to a disruption of the filamentous actin cytoskeleton in human pancreatic and cervical cancer cells which was accompanied by the activation of Jun-NH(2)-terminal kinase and p38(mapk). Similar effects were obtained by treatment of the cancer cells with cytochalasin D. These results suggest that nordihydroguaiaretic acid induces anoikis-like apoptosis as a result of disruption of the actin cytoskeleton in association with the activation of stress activated protein kinases. In conclusion, nordihydroguaiaretic acid could constitute a lead compound in the development of novel therapeutic agents for various types of cancer.  相似文献   
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