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Down-regulation of annexin A1 and A2 protein expression in intestinal-type sinonasal adenocarcinomas
Rodrigo JP García-Pedrero JM Llorente JL Fresno MF Allonca E Suarez C Hermsen M 《Human pathology》2011,42(1):88-94
Annexins are a structurally related family of calcium- and phospholipid-binding proteins that have been implicated in a broad range of molecular and cellular processes. The altered expression of individual annexins has been implicated in tumor development and progression. In this study the expression of annexin A1 and annexin A2 was studied by immunohistochemistry in intestinal-type sinonasal adenocarcinoma using a study set of 57 intestinal-type sinonasal adenocarcinomas represented on an intestinal-type sinonasal adenocarcinoma tissue microarray to assess its potential role in the pathogenesis of these tumors. Our results showed that annexin A1 expression was consistently lost in 52 (91%) intestinal-type sinonasal adenocarcinomas, as compared with the normal epithelium. The expression of annexin A2 was more heterogeneous, and only 19 (33%) cases showed annexin A2 negative expression. Annexin A2 expression was correlated with the histopathological type, being lower in the mucinous type (P = .022). The loss of annexin A2 expression correlated with a reduced survival in univariate analysis (P = .004). However, the impact of annexin A2 expression on patient survival could be an indirect consequence of its association with the histopathological type, since annexin A2 expression was not found to be an independent predictor in multivariate analyses. These results suggest that annexin A1 expression is frequently and commonly lost in intestinal-type sinonasal adenocarcinoma development. Annexin A2 expression is also reduced in intestinal-type sinonasal adenocarcinoma, and this loss of expression is associated to the more aggressive histopathological types. 相似文献
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Rocha L Lorigados-Pedre L Orozco-Suárez S Morales-Chacón L Alonso-Vanegas M García-Maeso I Villeda-Hernández J Osorio-Rico L Estupiñán B Quintana C 《Progress in neuro-psychopharmacology & biological psychiatry》2007,31(6):1208-1218
The main goal of the present study was to evaluate binding to serotonin in the neocortex surrounding the epileptic focus of patients with mesial temporal lobe epilepsy (MTLE). Binding to 5-HT, 5-HT(1A), 5-HT(4), 5-HT(7) receptors and serotonin transporter (5-HTT) in T1-T2 gyri of 15 patients with MTLE and their correlations with clinical data, neuronal count and volume were determined. Autopsy material acquired from subjects without epilepsy (n=6) was used as control. The neocortex from MTLE patients demonstrated decreased cell count in layers III-IV (21%). No significant changes were detected on the neuronal volume. Autoradiography experiments showed the following results: reduced 5-HT and 5-HT(1A) binding in layers I-II (24% and 92%, respectively); enhanced 5-HT(4) binding in layers V-VI (32%); no significant changes in 5-HT(7) binding; reduced 5-HTT binding in all layers (I-II, 90.3%; III-IV, 90.3%, V-VI, 86.9%). Significant correlations were found between binding to 5-HT(4) and 5-HT(7) receptors and age of seizure onset, duration of epilepsy and duration of antiepileptic treatment. The present results support an impaired serotoninergic transmission in the neocortex surrounding the epileptic focus of patients with MTLE, a situation that could be involved in the initiation and propagation of seizure activity. 相似文献
76.
In the central nervous system, transferrin (Tf) is produced by oligodendroglial cells (OLGcs) and is essential for their development. Recently, using the complete cDNA of the human Tf gene, we obtained clones overexpressing Tf in two OLGc lines, N19 and N20.1, which represent different stages of differentiation. We showed that the overexpression of this glycoprotein promotes the maturation and myelinogenic capacity of both cell lines. In this work, using cDNA array technology, we examined changes induced by Tf in 1,176 genes. We found 41 genes differentially expressed in both cell lines, all of them involved in OLGc development. In the less mature cells (N19) overexpressing Tf, there was a significant increase in key enzymes of neurosteroid metabolism, such as cholesterol side chain cleavage cytochrome P450, 3beta-hydroxysteroid dehydrogenase and 5alpha-reductase type 1. In the more mature cell line (N20.1), Tf overexpression produced an induction of several mRNAs of the GABA(A) receptor subunits, of thyroid hormone receptors and of proteins involved in axon-glia interactions such as F3/contactin. In addition, in both cell lines, Tf overexpression induced an increase in the expression of different isoforms of transforming growth factor beta receptors and in several genes related to mitochondrial function and to complex lipid metabolism, crucial steps in myelin synthesis. Differentiation produced by Tf in both cell lines seems to occur by modulation of different genes depending on the maturational stage of the cells. Our findings provide new insights into the molecular basis of OLGc differentiation and on the role played by Tf in this process. 相似文献
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The prevalence of child sexual abuse in community and student samples: A meta-analysis 总被引:4,自引:0,他引:4
Background
Studies conducted internationally confirm that child sexual abuse is a much more widespread problem than previously thought, with even the lowest prevalence rates including a large number of victims that need to be taken into account.Objective
To carry out a meta-analysis of the prevalence of child sexual abuse in order to establish an overall international figure.Methods
Studies were retrieved from various electronic databases. The measure of interest was the prevalence of abuse reported in each article, these values being combined via a random effects model. A detailed analysis was conducted of the effects of various moderator variables.Results
Sixty-five articles covering 22 countries were included. The analysis showed that 7.9% of men (7.4% without outliers) and 19.7% of women (19.2% without outliers) had suffered some form of sexual abuse prior to the age of eighteen.Conclusions
The results of the present meta-analysis indicate that child sexual abuse is a serious problem in the countries analysed. 相似文献79.
80.
Milagro Fernández-Delgado M. Alexandra García-Amado Monica Contreras Virginia Edgcomb Juana Vitelli Pulchérie Gueneau 《International journal of environmental health research》2009,19(4):279-289
The aim of this study was to characterize the virulence properties and the antimicrobial resistance of Vibrio cholerae isolates from a coastal area of the Caribbean Sea. Three V. cholerae isolates were obtained from seawater and plankton using the HP selective medium for Helicobacter pylori. These V. cholerae isolates belonged to the non-O1, non-O139 serogroups and they did not have cholera toxin genes. They were resistant to penicillins and some cephalosporins and were sensitive to netilmicin, tetracyclines, sulfamethoxazole-trimethoprim and quinolones. This is the first study that provides biochemical and molecular evidence of non-O1, non-O139 V. cholerae isolates, non-toxigenic, carrying antibiotic resistance in seawater and plankton from a coastal area of the Caribbean Sea. 相似文献