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1H pylori (CagA) and Epstein-Barr virus infection in gastric carcinomas:Correlation with p53 mutation and c-Myc,Bcl-2 and Bax expression显示文摘AIM: To investigate the interrelationship between H pylori and Epstein-Barr virus (EBV) infection in the gastric carcinogenesis having in focus the p53 mutation and the c-Myc, Bcl-2 and Bax expression. METHODS: seventy-one gastric carcinoma tissues were assessed by polymerase chain reaction (PCR) for H pylori and in situ hybridization for EBV. c-Myc, Bcl-2 and Bax expression were detected by immunohistochemistry and single-stranded conformational polymorphism (SSCP) for p53 mutation. RESULTS: The positivity rates for H pylori and EBV were 94.4% and 8.45%, respectively. The majority of the cases displayed only the H pylori presence. All EBV positive cases were also H pylori positive. None infectious agent was observed in 5.55% of the cases. The intestinal type tumor was more frequent in the co-infected and non-infected groups. The female predominated in the non-infected group showing statistical significance (70.4% vs 29.6%, P=0.039). The Bcl-2 was only detected in the group exclusively infected by H pylori. However, c-Myc and Bax were detected in the three groups but with a low frequency in the co-infected group. Mutation of p53 was present in all groups, with the highest frequencies in the H pylori positive groups. CONCLUSION: The frequency of H pylori infection in gastric carcinomas was high. The presented data indicated that gastric carcinogenesis has different pathways depending of the presence of the two investigated infectious agents, suggesting a possible involvement of H pylori with apoptotic process. The low expression of c-Myc and Bax in the EBV-positive groups suggests that EBV may inhibit the expression of these proteins. Nevertheless, p53 mutation shows to be a relevant alteration, independent of both infectious agents.Valeska Portela Lima Marcos Antonio Pereira de Lima Angela Rosa André Márcia Valéria Pitombeira Ferreira Marcos Aurélio Pessoa Barros Sílvia Helena Barem Rabenhorst 2008World Journal of Gastroenterology2008,14,6:17
2Interrelationship between chromosome 8 aneuploidy,C-MYC amplification and increased expression in individuals from northern Brazil with gastric adenocarcinoma显示文摘AIM: To investigate chromosome 8 numerical aberra- tions, C-MYC oncogene alterations and its expression in gastric cancer and to correlate these findings with histo- pathological characteristics of gastric tumors. METHODS: Specimens were collected surgically from seven patients with gastric adenocarcinomas. Immu- nostaining for C-MYC and dual-color fluorescence in situ hybridization (FISH) for C-MYC gene and chromosome 8 centromere were performed. RESULTS: All the cases showed chromosome 8 aneu- ploidy and C-MYC amplification, in both the diffuse and intestinal histopathological types of Lauren. No significant difference (P < 0.05) was observed between the level ofchromosome 8 ploidy and the site, stage or histological type of the adenocarcinomas. C-MYC high amplification, like homogeneously stained regions (HSRs) and double minutes (DMs), was observed only in the intestinal-type. Structural rearrangement of C-MYC, like translocation, was observed only in the diffuse type. Regarding C-MYC gene, a significant difference (P < 0.05) was observed between the two histological types. The C-MYC protein was expressed in all the studied cases. In the intestinal- type the C-MYC immunoreactivity was localized only in the nucleus and in the diffuse type in the nucleus and cytoplasm. CONCLUSION: Distinct patterns of alterations between intestinal and diffuse types of gastric tumors support the hypothesis that these types follow different genetic path- ways.Danielle Queiroz Calcagno Mariana Ferreira Leal Aline Damaceno Seabra Andre Salim Khayat Elizabeth Suchi Chen Samia Demachki Paulo Pimentel Assumpcao Mario Henrique Girao Faria Silvia Helena Barem Rabenhorst Márcia Valéria Pitombeira Ferreira Marília de Arruda Cardoso Smith Rommel Rodríguez Burbano 2006World Journal of Gastroenterology2006,12,38:9
3Helicobacter pylori and EBV in gastric carcinomas:Methylation status and microsatellite instability显示文摘AIM:To verify the methylation status of CDH1, DAPK, COX2, hMLH1 and CDKN2A genes and to evaluate their association with Helicobacter pylori (H. pylori)-cagA+ and Epstein Barr virus (EBV) infections in gastric adenocarcinomas.METHODS: Methylation-specific PCR (MSP) assay was performed in 89 primary gastric carcinomas (intestinal and diffuse types). Microsatellite instability (MSI) analysis was performed using the BAT26 primer set and PCR products were analyzed with the ABI PRISM 3100 Genetic Analyzer using Genescan 3.7 software (Applied Biosystems). Detection of H. pylori and genotyping were performed by PCR, using specifi c primers for ureaseC and cagA genes. The presence of EBV was assessed by in situ hybridization. Statistical analyses were performed using the χ2 or Fisher's exact test.RESULTS: The most frequent hypermethylated gene was COX-2 (63.5%) followed by DAPK (55.7%), CDH1 (51%), CDKN2A (36%) and hMLH1 (30.3%). Intestinal and diffuse adenocarcinomas showed different methylation profiles and there was an association between methylation of E-CDH1 and H. pylori-cagA+ in the intestinal adenocarcinoma type. MSI was correlated with hMLH1 methylation. There was an inverse correlation between DAPK hypermethylation and MSI.CONCLUSION: We found a strong association between CDH1 methylation and H. pylori-cagA+ in intestinal-type gastric cancer, association of MSI and better prognosis and an heterogeneous COX-2 overexpression.Adriana Camargo Ferrasi Nídia Alice Pinheiro Silvia Helena Barem Rabenhorst Otávia Luisa Caballero Maria Aparecida Marchesan Rodrigues Fabrício de Carvalho Celso Vieira de Souza Leite Marcia Valéria Pitombeira Ferreira Marcos Aurélio Pessoa Barros Maria Inês de Moura Campos Pardini 2010World Journal of Gastroenterology2010,16,3:6
4Inactivation of COX-2, HMLH1 and CDKN2A Gene by Promoter Methylation in Gastric Cancer: Relationship with Histological Subtype, Tumor Location and Helicobacter pylori Genotype显示文摘Alves Markênia Kélia Santos Ferrasi Adriana Camargo Lima Valeska Portela Ferreira Márcia Valéria Pitombeira De Moura Campos Pardini Maria Inês Rabenhorst Silvia Helena Barem 2011EN2011,,5:1
5^(11)C-PK11195 plasma metabolization has the same rate in multiple sclerosis patients and healthy controls:a cross-sectional study显示文摘^(11)C-PK11195 is a positron emitter tracer used for Positron Emission Tomography(PET)imaging of innate immune cell activation in studies of neuroinflammatory diseases.For the image quantitative analysis,it is necessary to quantify the intact fraction of this tracer in the arterial plasma during imaging acquisition(plasma intact fraction).Due to the complexity and costs involved in this analysis it is important to evaluate the real necessity of individual analysis in each 11C-PK11195 PET imaging acquisition.The purpose of this study is to compare 11CPK11195 plasma metabolization rate between healthy controls and multiple sclerosis(MS)patients and evaluate the interference of sex,age,treatment,and disease phenotype in the tracer intact fraction measured in arterial plasma samples.11C-PK11195 metabolization rate in arterial plasma was quantified by high performance liquid chromatography in samples from MS patients(n=50)and healthy controls(n=23)at 20,45,and 60 minutes after 11C-PK11195 injection.Analyses were also stratified by sex,age,treatment type,and MS phenotype.The results showed no significant differences in the metabolization rate of healthy controls and MS patients,or in the stratified samples.In conclusion,11C-PK11195 metabolization has the same rate in patients with MS and healthy controls,which is not affected by sex,age,treatment,and disease phenotype.Thus,these findings could contribute to exempting the necessity for tracer metabolization determination in all 11C-PK11195 PET imaging acquisition,by using a population metabolization rate average.The study procedures were approved by the Ethics Committee for Research Projects Analysis of the Hospital das Clinicas of the University of Sao Paulo Medical School(approval No.624.065)on April 23,2014.Aline Morais de Souza Milena Sales Pitombeira Larissa Estessi de Souza Fabio Luiz Navarro Marques Carlos Alberto Buchpiguel Caroline Cristiano Real Daniele de Paula Faria 2021Neural Regeneration Research2021,16,12:1
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