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Substance P is a peptide that exerts its activity through the interaction with specific receptors that are distributed in different brain areas. Given the potential of NK1 receptor antagonists as antidepressants, the availability of a peripheral model of NK1 receptors would be particularly relevant for the possibility to perform studies in samples of patients. Therefore, with the present study we aimed to explore the possible existence of NK1 receptors by means of [3H]SR140333 and [125I]BHSP that behave as, respectively, antagonist and agonist, at this level, in human blood lymphocytes and granulocytes of healthy donors. The results of the present study failed to detect the presence of a high-affinity and saturable binding of [3H]SR140333 and [125I]BHSP in human blood cells, whereas a specific binding for both compounds was found in rat cerebral cortex that was used as the control tissue. These findings would question the presence of NK1 receptors in human circulating cells.  相似文献   
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To investigate the potential involvement of the nitric oxide (NO) pathway in colorectal carcinogenesis, we correlated the expression and the activity of inducible nitric oxide synthase (iNOS) with the degree of tumor angiogenesis in human colorectal cancer. Tumor samples and adjacent normal mucosa were obtained from 46 surgical specimens. Immunohistochemical expression of iNOS, vascular endothelial growth factor (VEGF), and CD31 was analyzed on paraffin-embedded tissue sections. iNOS activity and cyclic GMP levels were assessed by specific biochemical assays. iNOS protein expression was determined by Western blot analysis. iNOS and VEGF mRNA levels were evaluated using Northern blot analysis. Both iNOS and VEGF expressions correlated significantly with intratumor microvessel density (r(s) = 0.31, P = 0.02 and r(s) = 0.67, P < 0.0001, respectively). A significant correlation was also found between iNOS and VEGF expression (P = 0.001). iNOS activity and cyclic GMP production were significantly higher in the cancer specimens than in the normal mucosa (P < 0.0001 and P < 0.0001, respectively), as well as in metastatic tumors than in nonmetastatic ones (P = 0.002 and P = 0.04, respectively). Western and Northern blot analyses confirmed the up-regulation of the iNOS protein and gene in the tumor specimens as compared with normal mucosa. NO seems to play a role in colorectal cancer growth by promoting tumor angiogenesis.  相似文献   
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AIMS: To investigate by immunohistochemical analysis the expression of the TCL1 oncogene product and of CD27 in 25 cases of primary cutaneous B-cell lymphomas (PCBCL) classified according to the World Health Organization-European Organization for Research and Treatment of Cancer classification of cutaneous lymphomas. In B-cell ontogenesis TCL1 is mainly expressed by 'naive' B lymphocytes and by a subset of germinal centre B cells, whereas CD27 is expressed by a subset of germinal centre B cells, 'memory' B lymphocytes and plasma cells, suggesting that their expression in physiological conditions is mutually exclusive. METHODS AND RESULTS: Overall, TCL1 was expressed in 5/25 cases (20%) and CD27 in 15/25 cases (60%). Furthermore, 7/25 cases (28%) were TCL1- and CD27- and 2/25 cases (8%) were TCL1+ and CD27+. In particular, primary cutaneous follicle-centre lymphomas (10 cases) showed a variable expression of both TCL1 and CD27, whereas primary cutaneous marginal-zone B-cell lymphomas (eight cases) showed, with the exception of a single case, a definite CD27+/TCL1- profile. CONCLUSIONS: These findings indicate: (i) the TCL1 oncogene product is uncommonly expressed in PCBCL (20% of cases, mainly of the follicle-centre subtype); (ii) in contrast, CD27 is often expressed in PCBCL (60% of cases), mainly of the marginal-zone subtype; (iii) the coexpression of TCL1 and CD27 may be seldom observed in PCBCL (8% of cases); (iv) PCBCL does not seem to show, in terms of either TCL1 or CD27 expression, significant differences compared with its systemic counterparts.  相似文献   
25.
Italian legislation regarding reproductive medicine limits the number of embryos transferred per attempt to three. Thus, in order to achieve pregnancy, more IVF cycles may be required, generating a need for methods of ovarian stimulation with fewer side effects. The gonadotrophin-releasing hormone (GnRH) antagonists have several advantages in this respect, but there is a debate regarding a possible lower pregnancy rate from resulting cycles. This study evaluated the clinical applicability of GnRH antagonists for ovarian stimulation in young women undergoing intracytoplasmic sperm injection (ICSI) in which only three oocytes can be fertilized. The 200 women treated with GnRH antagonist had a significantly shorter stimulation and lower gonadotrophin consumption, oestradiol concentration, total and mature oocyte recovery as compared with 200 matched controls treated with GnRH agonist. No differences were found between the groups in the number of normal zygotes, total cleaved, transferred and high quality embryos, or in the clinical outcomes. Thus, the previously reported lower pregnancy rate in GnRH antagonist cycles may be related to the oocyte characteristics. Finally, under conditions of oocyte number restriction, the GnRH antagonist-based cycles may be proposed as an efficacious, safe and minimally invasive alternative to GnRH agonist in a standard long protocol.  相似文献   
26.
The bcl-2 protein is a membrane protein involved in prolonging cell survival by inhibiting apoptosis. The HER-2 oncogene, which is located on chromosome 17 and encodes for a tyrosine-kinase growth factor receptor, is amplified and HER-2/neu is overexpressed in 25% to 30% of breast carcinomas. The authors analyzed the bcl-2 expression and the bcl-2 gene and HER-2/neu overexpression and amplification in FIGO stage IIIC, serous, G3, ovarian carcinomas obtained from living patients who had no evident disease 5 years after primary treatment compared with ovarian carcinomas obtained from patients, matched for stage, grade of differentiation, and treatment, who had died of progression of disease no later than 2 years after primary treatment. bcl-2 overexpression was statistically correlated with progression of disease during first-line chemotherapy (P=0.021). The HER-2/neu status was found not to correlate with progression of disease during first-line chemotherapy. Both bcl-2 and HER-2/neu expression were not statistically associated with the clinical outcome of ovarian cancer patients. Gene amplification of the HER-2/neu chromosome 17 was found in all the HER-2/neu, 3+ score, positive-staining ovarian carcinomas. None of the analyzed samples revealed a translocation t(14;18)(q32;q21) in the bcl-2 gene. The knowledge of additional prognostic or even predictive factors, such as bcl-2 expression, in patients with advanced ovarian carcinoma before the primary chemotherapeutic treatment may help in the management of patients who require a more tailored treatment. In addition, the gene amplification of the HER-2/neu suggests that HER-2 is a potential target for treatment in ovarian cancer.  相似文献   
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The Crouzon syndrome, which is associated with fibroblast growth factor receptor (FGFR2) mutations, is characterized by premature fusion of cranial sutures. We used an in vitro model of cultured periosteal fibroblasts from normal subjects and from Crouzon patients with FGFR2 mutation. We analyzed the matrix turnover rate and the effects of adding FGF2 by evaluating fibronectin synthesis and the activity of some proteolytic enzymes. To assess the role of some FGF signaling molecules involved in FGFR2 regulation, we studied Grb2 tyrosine phosphorylation and the phosphotyrosine proteins associated with Grb2. The iodinate FGF binding assay was performed to quantify FGFR expression. Compared with normal fibroblasts, fibronectin synthesis was decreased in Crouzon fibroblasts, and protease activities in cells and medium were enhanced, suggesting that excess fibronectin catabolism is present. Differences were more marked when FGF2 was added. Very few phosphoproteins were visible in anti-Grb2 immunoprecipitations from Crouzon fibroblasts, which showed a significant increase in the number of high-affinity and low-affinity FGF2 receptors. These results suggest that the abnormal genotype and the Crouzon cellular phenotype are related. To compensate the low levels of tyrosine phosphorylation, Crouzon cells might increase the numbers of FGFR2, thus increasing the cell surface binding sites for FGF2.  相似文献   
29.
We analyzed in advanced ovarian serous G3 carcinoma the correlation between epidermal growth factor receptor (EGFR) overexpression and tumor angiogenesis and their relation with clinical outcome. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) were statistically correlated with disease-free interval and death from disease both in univariate and multivariate analyses while EGFR expression was not correlated with clinical outcome. MVD was significantly associated with progression of disease during chemotherapy while VEGF and EGFR expression were not correlated with responsiveness to chemotherapy (Fisher's exact test). VEGF expression was correlated with MVD (Fisher's exact test). EGFR showed a trend to correlation with MVD. Further studies focusing on the use of angiogenesis inhibitors in addition to EGFR inhibitors on ovarian carcinoma cells may produce therapeutic strategies in the selection of tailored therapies in ovarian cancer patients.  相似文献   
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