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81.
Trahan S  Têtu B  Raymond PE 《Human pathology》2005,36(12):1316-1321
Serous papillary carcinoma is an aggressive tumor. Point mutations in the p53 suppressor gene might explain in part the rapid growth of this malignant tumor and its unfavorable outcome. The aims of this study were to evaluate the behavior of serous papillary carcinoma developing in endometrial polyps and to assess the p53 protein overexpression. Patients included in this study were treated in our institution between 1982 and 2003. All clinical and pathological materials were examined. A p53 protein immunohistochemical analysis was performed on paraffin-embedded tissues. Thirteen serous papillary carcinomas arising from benign polyps of the endometrium were identified. The patients' age averaged 73 years. All patients were treated surgically. After an average follow-up of 22 months, 54% of the patients were dead or alive with disease. Of 10 serous papillary carcinomas, 8 (80%) for which paraffin blocks were available overexpressed the p53 protein. A serous papillary carcinoma arising from benign polyps of the endometrium remains a malignant neoplasia with an unfavorable outcome even if the primary tumor is limited to the polyp. The high rate of protein p53 overexpression suggests that a p53 gene mutation occurs early in the disease and might explain the rapid growth of the tumor.  相似文献   
82.
β-Endorphin stimulates phytohemagglutinin-induced production of IL-4 and does not modify the production of γ-IFN in nonfractionated leukocyte suspension. In a culture of purified CD4+ T-cells, β-endorphin does not modify the levels of IL-4 and γ-IFN, but stimulates the production of IL-4 and inhibits γ-IFN production after addition of monocytes to CD4+ lymphocytes. Stimulation of IL-4 synthesis by β-endorphin is mediated by the cycloxygenase cycle products. Hence, β-endorphin shifts T-helper polarization towards Th2 cells with subsequent predominance of the humoral form of the immune response. Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 146, No. 10, pp. 427-430, October, 2008  相似文献   
83.
To elucidate the mechanism underlying crescentic formation, we assessed the phenotypic characterization and cell-cycle protein expression in human crescentic glomerulonephritis (CRGN). Kidney tissue specimens taken from CRGN patients (10 patients with pauci-immune type rapidly progressive glomerulonephritis (RPGN), 2 patients with Henoch-Schönlein purpura nephritis, and 1 patient with IgA nephropathy) were examined immunohistochemically. Most of the cellular components of the crescents expressed cytokeratin, whereas few cells expressed PHM-5. CD68-positive cells were minor components of cellular crescents, indicating that the major principal cellular component of the crescents is made up of cells with the parietal glomerular epithelial cell (PEC) phenotype. Additionally, serial section analysis revealed that Ki-67-positive cells in the crescents were frequently cyclin-A positive and Bcl-2 positive, but seldom cyclin-B1 positive. Moreover, the expression of cyclin-dependent kinase inhibitor p27Kip1 was low in the cellular crescents, despite being exclusively positive in podocytes within the same section. We concluded that the major component of the cellular crescents is made up of PECs and that apparent expression of cyclins and Bcl-2 and restrained expression of p27Kip1 may be synergistically associated with the development of cellular crescents in human CRGN.  相似文献   
84.
We have developed a microarray (DotScan) that enables rapid immunophenotyping and classification of leukaemias and lymphomas by measuring the capture of cells by immobilized dots of 82 CD antibodies [Belov, L., de la Vega, O., dos Remedios, C.G., Mulligan, S.P., 2001. Immunophenotyping of leukemia using a cluster of differentiation antibody microarray. Cancer Res. 61, 4483; Belov, L., Huang, P., Barber, N., Mulligan, S.P., Christopherson, R.I., 2003. Identification of repertoires of surface antigens on leukemias using an antibody microarray. Proteomics 3, 2147]. The DotScan technology has been used to investigate the properties of 498 new antibodies submitted to the HLDA8 Workshop. These antibodies have been applied as 10 nl dots to a film of nitrocellulose on a microscope slide to make an HLDA8 microarray. After blocking the remaining nitrocellulose surface, individual arrays were incubated with each of 7 cell types from a human leukaemia cell panel consisting of three cell lines, CCRF-CEM (a T-cell acute lymphocytic leukaemia), MEC-1 (derived from B-cell chronic lymphocytic leukaemia) and HL-60 (a promyelocytic leukaemia), and four leukaemias from patients: a T-cell prolymphocytic leukaemia, a B-cell chronic lymphocytic leukaemia, and two acute myeloid leukaemias. Leukaemia cells were captured by those immobilized antibodies for which they expressed the corresponding surface molecule. Unbound cells were gently washed off, bound cells were fixed to the arrays and dot patterns were recorded using a DotScan array reader and quantified using DotScan data analysis software. The data obtained show the unique expression profiles of the 7 cell types in the leukaemia cell panel obtained with the DotScan microarray, and the differential capture patterns for these 7 cell types screened against the 498 antibodies in the HLDA8 microarray constructed for this study.  相似文献   
85.
Prayson RA 《Human pathology》2004,35(3):317-321
Protoplasmic astrocytomas are rare gliomas whose nosology remains enigmatic. This study retrospectively reviews the clinicopathologic features of eight tumors, including evaluation of these neoplasms for chromosome 1p loss, Bcl-2 immunoreactivity, and cyclooxygenase-2 immunoreactivity. Patients ranged in age from 3 to 49 years (median 25.5 years) and included six males and two females. All patients presented with a period of seizures (median duration of period, 54 months) before surgery. Five tumors were either totally or partially based in the temporal lobe. In the six patients for whom follow-up information was available, there was no evidence of recurrence at last known follow-up (range 5 to 171 months; median 134 months). Histologically, all tumors were marked by a proliferation of cells with rounded to oval nuclear contours and a paucity of cytoplasmic processes, arranged against a microcystic background. A rare mitotic figure was observed in only one tumor. Vascular proliferative changes and necrosis were not seen in any of the tumors. None of the tumors showed allelic loss on chromosome 1p by fluorescent in situ hybridization (FISH) analysis. Cyclooxygenase-2 (an enzyme involved in the conversion of arachidonate to prostaglandin H2 and G2) immunoreactivity was observed in two tumors. Bcl-2 (an anti-apoptotic protein) immunoreactivity was also confined to two tumors. In conclusion, protoplasmic astrocytomas appear to be low-grade neoplasms, as evidenced by their relatively benign clinical course. Although they histologically resemble microcystic oligodendrogliomas, none of the tumors showed allelic loss on chromosome 1p, a finding that has been described in the majority of low-grade oligodendrogliomas. This suggests that the protoplasmic astrocytoma is a distinct entity from low-grade oligodendroglioma. Similar to other low-grade astrocytomas, only a minority of tumors show evidence of cyclooxygenase-2 and Bcl-2 immunoreactivity.  相似文献   
86.
Local recurrence is a serious complication of breast carcinoma that reduces quality of life and influences prognosis. The aim of this study was to determine whether local recurrences of breast carcinoma are genetically related to the primary tumours. Forty cases of locally recurrent breast carcinomas (median onset: 3.6 years after primary surgery) were analysed: 22 patients had undergone breast-conserving therapy and 18 mastectomy. Eighteen microsatellites on chromosomes 2p, 3p, 5q, 10q, 11p, 11q, 13q, 17q, 17p, 18p were amplified by PCR using fluorescent-labelled primers, automatically detected after polyacrylamide gel electrophoresis and analysed for loss of heterozygosity (LOH) or microsatellite instability (MSI). Follow-up data were available for 39 cases with a median value of 89 months. All LOH and MSI found in the primary tumours were also present in the corresponding recurrences, indicating that they are genetically related to the primary tumours and not secondary malignancies in the same breast. MSI was found in three cases, of which one harboured MSI at more than two loci. The median value of LOH per case was significantly higher in the recurrent (four per case) compared to the primary tumours (two per case; p < 0.001, Mann-Whitney test), reflecting the genotype of tumour progression. Early local recurrence was associated with specific LOH for TP53.15 (p = 0.018, log-rank test) in the primary tumours. LOH on D13S1699 or D17S855 was associated with lymph node metastases (p = 0.024 and p = 0.019, respectively; chi-square test). In addition, tumour grade, lack of oestrogen or progesterone receptor expression, young patient age and early appearance of local recurrence significantly correlated with poor survival. The development of local recurrence despite clear resection margins may result from residual DCIS distant from the invasive carcinoma, homing of circulating tumour cells, or genetically altered, histologically normal breast tissue not immediately adjacent to the invasive carcinoma.  相似文献   
87.
88.
Cytotoxic T lymphocytes (CTL) play a major role in the rejection of tumor cells, but tumor rejection does not always occur in vivo, indicating that defects in anti-tumor immune responses may be common. We here document a novel function for CD44--using lung cancer cells, we showed that stimulation of CD44 reduced Fas expression and Fas-mediated apoptosis: (i) lung cancer cells expressed high levels of CD44; (ii) engagement of CD44 on the cells by a specific antibody or fragmented hyaluronan reduced Fas expression; (iii) CD44 cross-linking reduced Fas-mediated apoptosis; (iv) stimulation of CD44 on lung cancer cells decreased IFN-gamma production by autologous CTL; and (v) CD44 stimulation prevented killing of lung cancer cells by autologous CTL. Based on these findings, we postulate a new concept--that interaction of CD44 on lung cancer cells with fragments of extracellular hyaluronan present in the surrounding extracellular matrix reduces Fas expression as well as Fas-mediated apoptosis of cancer cells. This leads to reduced susceptibility of the cells to CTL-mediated cytotoxicity through the Fas-Fas ligand pathway.  相似文献   
89.
Chang MS  Kim WH  Kim CW  Kim YI 《Histopathology》2000,37(4):309-315
AIMS: To clarify the relationship between the Epstein-Barr virus (EBV) and gastric carcinoma with lymphoid stroma (GCLS) in Koreans, and to characterize the EBV-positive GCLS. METHODS AND RESULTS: EBV infection was examined using EBER in-situ hybridization and polymerase chain reaction in 45 cases of GCLS among Koreans, and in 292 consecutive cases of gastric carcinomas without lymphoid stroma (non-GCLS) as controls. EBV infection was found in 30 tumours (67%) of GCLS and 10 tumours (3.4%) of non-GCLS (P < 0.05). EBV-positive GCLS was more prevalent in males, poorly differentiated histological type and diffuse type in Lauren's classification, and tended to be located more in the middle third of the stomach than EBV-negative GCLS (P < 0.05). p53 overexpression was observed in 22% of GCLS (17% of EBV-positive GCLS and 33% of EBV-negative GCLS), and 34% of non-GCLS (EBV-positive GCLS vs. non-GCLS: P = 0.056). The survival of the patient with GCLS was not correlated with EBV infection or p53 immunoexpression (follow-up period: 11-97 months). CONCLUSIONS: GCLS in Koreans is strongly associated with EBV infection. The prognosis in GCLS is not dependent upon either the status of EBV infection or the status of p53 immunoexpression.  相似文献   
90.
Summary The effects of beta-adrenergic agonists such as isoproterenol, norepinephrine and epinephrine upon the adenylate cyclase activity of human fat cell ghosts were tested, each alone and in combination with the beta-blocking agent propranolol. Saturating concentrations of these agents showed a 2–6.5-fold increase of enzyme activity without addition of any artificial cofactors. Isoproterenol was more potent in stimulating the enzyme system than epinephrine and nor-epinephrine. Propranolol caused a dose-dependent rightward shift of the log-dose response curve of these beta-adrenergic agonists. The assay of human fat cell adenylate cyclase in vitro may provide a simple and convenient assay system for the screening of beta-adrenergic drugs of potential therapeutic importance.Herrn Prof. Dr. Dr. h.c. G. Schettler zum 60. Geburtstag gewidmet  相似文献   
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