Laryngeal carcinomas are aggressive neoplasms with controversial association with the human papillomavirus (HPV) and Epstein-Barr virus (EBV). So far, the impairment of p53 protein function and its impact on cellular proliferation has not been studied adequately in these tumors. In this work, molecular biologic techniques were used to assess the frequency of HPV and EBV in 110 squamous cell carcinomas of the larynx. In addition, accumulation of p53 and Ki-67 cell proliferation antigen expression in malignant cells was assessed by immunohistochemical analysis. High-grade HPV was found in 37.3% of cases, and none had demonstrable EBV infection. Accumulation of p53 was found in 78.2% of the cases, and it was related to a high Ki-67 labeling index and higher histologic grade. The results demonstrate association of HPV with more than one third of laryngeal carcinomas studied, mainly glottic tumors. Tumors with increased cell proliferation were more frequently high grade, with p53 accumulation and lymph node metastasis.
Epstein-Barr virus (EBV) is a ubiquitous herpesvirus, and most people have serological evidence of previous viral infection at adult age. EBV is associated with infectious mononucleosis and human cancers, including some lymphomas and gastric carcinomas. Although EBV was first reported in lymphoepithelioma-like gastric carcinoma, the virus was also found in conventional adenocarcinomas. In the present study, 53 gastric carcinomas diagnosed in São Paulo State, Brazil, were evaluated for EBV infection by non-isotopic in situ hybridization with a biotinylated probe (Biotin-AGACACCGTCCTCACCACCC GGGACTTGTA) directed to the viral transcript EBER-I, which is actively expressed in EBV latently infected cells. EBV infection was found in 6 of 53 (11.32%) gastric carcinomas, mostly from male patients (66.7%), with a mean age of 59 years old. Most EBV-positive tumors were in gastric antrum. Two EBV-positive tumors (33.3%) were conventional adenocarcinomas, whereas four (66.7%) were classified as lymphoepithelioma-like carcinomas. EBV infection in gastric carcinomas was reported elsewhere in frequencies that range from 5.6% (Korea) up to 18% (Germany). In Brazil, a previous work found EBV infection in 4 of 80 (5%) gastric carcinomas, whereas another study found 4.7 and 11.2% of EBV-positive gastric carcinomas of Brazilians of Japanese origin or not, respectively. In the present study, the frequency of EBV-positive gastric carcinomas is similar to that reported in other series, and the clinicopathologic characteristics of these EBV-positive tumors are in agreement with the data in the literature.
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O objetivo principal deste trabalho é analisar as variáveis que determinam o comércio entre Brasil-China, considerando uma classificação proposta para commodities agrícolas, minerais e produtos industriais. Adotouse um modelo de auto-regressão vetorial com correção de erro (VECM), através da decomposição de Bernanke. O período de análise compreendeu de 1995 a 2008. Os resultados indicam um alto poder explanatório da variável renda sobre a dinâmica das exportações para as três categorias avaliadas. Adicionalmente, a utilização da capacidade instalada apresentou coeficientes consistentes, mostrando que tal variável conseguiu captar corretamente os efeitos da demanda interna sobre as exportações. The main objective of this work is to analyze the variables that determine the bilateral trade between Brazil and China, considering a classification proposed for the agricultural and mineral commodities and processed products. A vector-auto regression model with error correction (VECM) was adopted, through the Bernanke decomposition. The analysis period was from 1995 to 2008. The results indicate a high explanatory power of the income variable on the exports dynamics. In addition, the capacity utilization had consistent coefficients for all models estimated showing that this variable was able to capture correctly the effects of the domestic demand on exports
Abstract:Brazil is currently the world's largest sugar producer and exporter, as well as the world's largest producer and consumer of sugarcane ethanol as a transportation fuel. The growth of this market originates from a combination of government policies and technological change, in both the sugarcane ethanol processing sector and the manufacture of flex-fuel vehicles. In recent years however, ethanol production has been questioned due to its possible impact on food prices. The present paper aims to explore the impact of Brazilian ethanol prices on sugar and gasoline prices. The relationships between a times series of these prices are investigated using a Vector Error Correction Model (VECM), supported by Granger Causality tests. In addition, Impulse Response Functions (IRFs) and Forecast Error Variance Decompositions (FEVD) are computed in order to investigate the dynamic interrelationships within these series. Our results suggest that ethanol prices are affected by both food and fuel prices, but that there is no strong evidence that changes in ethanol prices have an impact on food prices.
Laryngeal carcinomas are aggressive neoplasms with controversial association with the human papillomavirus (HPV) and Epstein-Barr virus (EBV). So far, the impairment of p53 protein function and its impact on cellular proliferation has not been studied adequately in these tumors. In this work, molecular biologic techniques were used to assess the frequency of HPV and EBV in 110 squamous cell carcinomas of the larynx. In addition, accumulation of p53 and Ki-67 cell proliferation antigen expression in malignant cells was assessed by immunohistochemical analysis. High-grade HPV was found in 37.3% of cases, and none had demonstrable EBV infection. Accumulation of p53 was found in 78.2% of the cases, and it was related to a high Ki-67 labeling index and higher histologic grade. The results demonstrate association of HPV with more than one third of laryngeal carcinomas studied, mainly glottic tumors. Tumors with increased cell proliferation were more frequently high grade, with p53 accumulation and lymph node metastasis.
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