Biologia e controle microbiano de Urbanus acawoios (Williams, 1926) (Lepidoptera: Hesperiidae): II. patologia e susceptibilidade em larvas infectadas por Bacillus thuringiensis Var. kurstaki (H-3a:3b)

Devido à falta de informações sobre Urbanus acawoios (Williams, 1926) (Lepidoptera: Hesperiidae), e pelos danos severos por ele causados em árvores de Clitoria racemosa, o presente trabalho foi desenvolvido sob condições de laboratório para verificar a possibilidade de utilizar Bacillus thuringiensis var. kurstaki (H-3a:3b) como agente microbiano para o seu controle. O pH do intestino médio do hesperídeo mostrou ser bastante alcalino, variando de 8,4 a 9,2 (média de 8,7), indicando a possibilidade das larvas serem susceptíveis ao patógeno. Os ensaios confirmaram a alta susceptibilidade a dosagens equivalentes a 110 g / ha, resultando em tempos letais medianos (TL50) de 42,28, 37,18, 28,00 e 51,87 horas para larvas de 3o, 4°, início e final do 5º ínstares, respectivamente. Três outras dosagens (80, 150 e 280 g/h) foram aplicadas para larvas do 3º ínstar, resultando em TLs50 de 42,62, 30,77 e 30,06 horas, respectivamente. Descrições detalhadas sobre os sintomas externos nas larvas infectadas foram dadas. As alterações histológicas do intestino médio afetado pela d-endotoxina de B. thuringiensis foram descritas. Os resultados obtidos no presente trabalho revelam a grande possibilidade de controlar esta praga utilizando-se produtos e formulados à base desta bactéria.

Sequencing of E2 and NS5A regions of HCV genotype 3a in Brazilian patients with chronic hepatitis

Hepatitis C virus (HCV) is a major cause of liver disease throughout the world. The NS5A and E2 proteins of HCV genotype 1 were reported to inhibit the double-stranded (ds) RNA-dependent protein kinase (PKR), which is involved in the cellular antiviral response induced by interferon (IFN). The response to IFN therapy is quite different between genotypes, with response rates among patients infected with types 2 and 3 that are two-three-fold higher than in patients infected with type 1. Interestingly, a significant percentage of HCV genotype 3-infected patients do not respond to treatment at all. The aim of this paper was to analyse the sequences of fragments of the E2 and NS5A regions from 33 outpatients infected with genotype 3a, including patients that have responded (SVR) or not responded (NR) to treatment. HCV RNA was extracted and amplified with specific primers for the NS5A and E2 regions and the PCR products were then sequenced. The sequences obtained covered amino acids (aa) 636-708 in E2 and in NS5A [including the IFN sensitivity determining region (ISDR), PKR-binding domain and extended V3 region)]. In the E2 and NS5A regions, we did observe aa changes among patients, but these changes were not statistically significant between the SVR and NR groups. In conclusion, our results suggest that the ISDR domain is not predictive of treatment success in patients infected with HCV genotype 3a.

Efeitos da incorporação de peneiras moleculares 3A, 4A, 5A e 13X em membranas compósitas de quitosana/poli(vinil álcool)

The composite membranes prepared via incorporation of 12.5% of molecular sieves 3A, 4A, 5A and 13X into chitosan/poly(vinyl alcohol) (1:1). The composite membranes were immersed in the cross-linker sulfuric acid in order to acquire high proton conductivity for applications in electrolytes in PEMCF and DMF. The influence of the molecular sieves on the structural, optical, thermal, mechanical, morphologic and protonic conductivity properties and water/methanol swelling degree of membranes were investigated.

Effect of activation of canonical Wnt signaling by the Wnt-3a protein on the susceptibility of PC12 cells to oxidative and apoptotic insults

Wnt proteins are involved in tissue development and their signaling pathways play an important role during embryogenesis. Wnt signaling can promote cell survival, which is beneficial for neurons, but could also lead to tumor development in different tissues. The present study investigated the effects of a Wnt protein on the susceptibility of a neural tumor cell line (PC12 cells) to the cytotoxic compounds ferrous sulfate (10 mM), staurosporine (100 and 500 nM), 3-nitropropionic acid (5 mM), and amyloid β-peptide (Aβ25-35; 50 µM). Cells (1 x 10(6) cells/mL) were treated with the Wnt-3a recombinant peptide (200 ng/mL) for 24 h before exposure to toxic insults. The Wnt-3a protein partially protected PC12 cells, with a 6-15% increase in cell viability in the presence of toxic agents, similar to the effect measured using the MTT and lactate dehydrogenase cell viability assays. The Wnt-3a protein increased protein expression of β-catenin by 52% compared to control. These findings suggest that Wnt signaling can protect neural cells against apoptosis induced by toxic agents, which are relevant to the pathogenesis of Alzheimer’s and Huntington’s diseases.

Potencial cognitivo P300 realizado em campo livre: aplicabilidade do teste

Avaliar a função auditiva em usuários de dispositivos eletrônicos aplicados a surdez é muito importante para o processo de reabilitação. Entretanto, nestes indivíduos os procedimentos devem ser realizados em campo livre. OBJETIVO: Analisar a aplicabilidade do potencial cognitivo P300 pesquisado em campo livre. FORMA DE ESTUDO: Clínico prospectivo. MATERIAL E MÉTODO: Foram avaliados 33 indivíduos de ambos os sexos com idade entre 7 e 34 anos, com audição normal e sem fator de risco para problemas mentais. O potencial cognitivo P300 foi realizado por meio do equipamento Biologic's Evoked Potential System (EP), com fones de inserção (3A) e em campo livre (0º Azimute e 45º Azimute). RESULTADOS: Não houve diferença estatisticamente significante para a latência do N2 e P300 e amplitude do P300 quando analisado o sexo e o modo de realização do teste (fone e campo livre), assim como não houve diferença ao comparar as medidas em campo livre a 0º e 45º Azimute. CONCLUSÃO: A pesquisa do potencial cognitivo P300 em campo livre é um procedimento viável de ser realizado.

Prevalência, fatores de risco e genótipos da hepatite C entre usuários de drogas

OBJETIVO: Estimar a prevalência e fatores associados à infecção pelo vírus da hepatite C em usuários de drogas e identificar os genótipos e subtipos virais circulantes. MÉTODOS: Estudo realizado com 691 usuários de drogas de 26 centros de tratamento de uso de drogas filantrópicos, particulares e públicos de Goiânia (GO) e Campo Grande (MS), entre 2005 e 2006. Dados sociodemográficos e fatores de risco para infecção pelo HCV foram obtidos por meio de entrevistas. Amostras sangüíneas foram testadas para a detecção de anticorpos para o HCV. As amostras positivas foram submetidas à detecção do RNA-HCV pela reação em cadeia da polimerase com iniciadores complementares às regiões 5' NC e NS5B do genoma viral e genotipadas pelo line probe assay (LiPA) e por seqüenciamento direto, seguido de análise filogenética. Prevalência e odds ratio foram calculados com intervalo de 95% de confiança. Os fatores de risco com p<0,10 pela análise univariada foram analisados por regressão logística hierárquica. Valores de p<0,05 foram considerados estatisticamente significantes. RESULTADOS: A prevalência para anti-HCV foi 6,9% (IC 95%: 5,2;9,2). A análise multivariada de fatores de risco indicou que idade superior a 30 anos e uso injetável de drogas se mostraram associados à infecção pelo HCV. O RNA-HCV foi detectado em 85,4% (41/48) das amostras anti-HCV positivas. Trinta e três amostras foram do genótipo 1 pelo LiPA, subtipos 1a (63,4%) e 1b (17,1%), e 8 (19,5%) do genótipo 3, subtipo 3a. A análise filogenética da região NS5B mostrou que 17 (68%), 5 (20%) e 3 (12%) amostras foram dos subtipos 1a, 3a e 1b, respectivamente. CONCLUSÕES: Os resultados mostram uma prevalência elevada da infecção e do subtipo 1a do HCV em usuários de drogas, sendo o uso injetável de drogas o principal fator de risco para essa infecção.

Chronic hepatitis C virus infections in Brazilian patients: association with genotypes, clinical parameters and response to long term alpha interferon therapy

The present study assessed the clinical significance of hepatitis C virus (HCV) genotypes and their influence on response to long term recombinant-interferon-alpha (r-IFN-a) therapy in Brazilian patients. One hundred and thirty samples from patients previously genotyped for the HCV and with histologically confirmed chronic hepatitis C (CH-C) were evaluated for clinical and epidemiological parameters (sex, age, time of HCV infection and transmission routes). No difference in disease activity, sex, age or mode and time of transmission were seen among patients infected with HCV types 1, 2 or 3. One hundred and thirteen of them were treated with 3 million units of r-IFN-a, 3 times a week for 12 months. Initial response (IR) was significantly better in patients with genotype 2 (100%) and 3 (46%) infections than in patients with genotype 1 (29%) (p < 0.005). Among subtypes, difference in IR was observed between 1b and 2 (p < 0.005), and between 1b and 3a (p < 0.05). Sustained response (SR) was observed in 12% for (sub)type 1a, 13% for 1b, 19% for 3a, and 40% for type 2; significant differences were found between 1b and 2 (p < 0.001), and between 1b and 3a (p < 0.05). Moreover, presence of cirrhosis was significantly associated with non response and response with relapse (p < 0.05). In conclusion, non-1 HCV genotype and lack of histological diagnosis of cirrhosis were the only baseline features associated with sustained response to treatment. These data indicate that HCV genotyping may have prognostic relevance in the responsiveness to r-IFN-a therapy in Brazilian patients with chronic HCV infection, as seen in other reports worldwide.

Distribution of hepatitis C virus genotypes among blood donors from mid-west region of Brazil

In order to investigate the hepatitis C virus (HCV) genotypes in mid-west region of Brazil, 250 anti-HCV positive blood donors were studied. Among them, the anti-HCV serological status was confirmed in 205 (82%). HCV RNA was detected in 165 samples, which were genotyped. HCV types 1, 2 and 3 were found in 67.9%, 3% and 29.1% of the donors, respectively. In Goiás state, subtype 1a (50%) was the most prevalent, followed by subtypes 3a (30.9%) and 1b (16.7%). In Mato Grosso state, subtype 1a was also predominant (41%), followed by subtypes 1b (29.5%) and 3a (25%). In Mato Grosso do Sul state, subtypes 1a and 1b were detected equally (36.8%), followed by 3a (21.1%). Subtype 2b was rare (2.4%, 4.5% and 5.3%, respectively). In Distrito Federal, subtype 3a (39%) was more frequent than 1a (31.7%) and the remaining (29.3%) belonged to subtype 1b.

Hepatitis C virus genotypes in hemodialysis patients in the Federal District, Brazil

Hepatitis C virus (HCV) genotypes and subtypes were determined in hemodialysis patients in the Federal District, Brazil, by sequencing of the 5' noncoding (NC) and nonstructural 5B (NS5B) regions. From 761 patients, 66 anti-HCV-positive samples were tested for HCV RNA. All 51 HCV RNA-positive samples by PCR of the 5' NC region were genotyped as genotypes 1 (90.2%) and 3 (9.8%). Subtype 1a (82.3%) was the most prevalent, followed by subtypes 3a (9.8%), 1b (5.9%) and 1a/1b (2.0%). Forty-two samples could be amplified and genotyped in the NS5B region: 38 (90.5%) as genotype 1, subtypes 1a, and 8 (9.5%) as genotype 3, subtype 3a. For the 42 samples sequenced in both regions, the genotypes and subtypes determined were concordant in 100% and 95.2% of cases, respectively. Two samples presented discrepant results, with the 5' NC region not distinguishing correctly the subtypes 1a and 1b. These findings indicate that the HCV genotype 1, subtype 1a, is the most prevalent among hemodialysis patients in the Federal District, Brazil.

HEPATOCELLULAR CARCINOMA IN A NON-CIRRHOTIC PATIENT WITH SUSTAINED VIROLOGICAL RESPONSE AFTER HEPATITIS C TREATMENT

Chronic infection by hepatitis C virus (HCV) is one of the main risk factors for the development of liver cirrhosis and hepatocellular carcinoma. However, the emergence of hepatocellular carcinoma (HCC) in non-cirrhotic HCV patients, especially after sustained virological response (SVR) is an unusual event. Recently, it has been suggested that HCV genotype 3 may have a particular oncogenic mechanism, but the factors involved in these cases as well as the profile of these patients are still not fully understood. Thus, we present the case of a non-cirrhotic fifty-year-old male with HCV infection, genotype 3a, who developed HCC two years after treatment with pegylated-interferon and ribavirin, with SVR, in Brazil.

Alta prevalência do genótipo 1 em portadores de hepatite C crônica em Belo Horizonte, MG

O vírus da hepatite C é caracterizado pela significativa heterogeneidade genética e é atualmente classificado em seis genótipos principais e diversos subtipos. A determinação do genótipo do vírus tem importância na prática clínica para orientar o tratamento dos pacientes portadores de hepatite C crônica. A prevalência dos diferentes genótipos e subtipos do vírus da hepatite C não tem sido amplamente estudada em algumas regiões do Brasil. Neste estudo foram analisadas 788 amostras de pacientes portadores de hepatite C crônica atendidos nos Centros de Referência em Hepatites Virais de Belo Horizonte, entre 2002 e 2006. A genotipagem do vírus foi realizada por seqüenciamento direto da região 5’ UTR. Adicionalmente, foi realizada análise filogenética incluindo todas as variantes genotípicas obtidas. Observou-se alta prevalência do genótipo 1 (78,4%; 1b [40,4%], 1a [37,5%] e 1a/b [0,5 %]), seguida pelo genótipo 3a (17,9%) e pelo 2b (3,1%). Foram identificadas três amostras (0,4%) com o genótipo 2a/c e duas amostras (0,2%) com o genótipo 4. A análise filogenética mostrou a segregação esperada das seqüências obtidas junto às seqüências de referência para os genótipos 1, 2, 3 e 4, exceto em duas amostras do genótipo 1a. A alta prevalência do genótipo 1 (78,4%), encontrada na população de Belo Horizonte é semelhante à previamente descrita em outras cidades, como Rio de Janeiro, mas superior à encontrada em São Paulo e no Sul do país. A presença de raras seqüências atípicas da região 5’UTR sugere a presença de variantes do vírus da hepatite C nesta população.

Hepatite C e gestação: análise de fatores associados à transmissão vertical

INTRODUÇÃO: Informações sobre hepatite C durante a gestação em serviços brasileiros são escassas. O objetivo deste estudo foi verificar os fatores associados à transmissão vertical do vírus da hepatite C em gestantes. MÉTODOS: Estudo observacional, transversal, realizado em gestantes procedentes do município de Campo Grande/MS, que apresentaram sorologia reagente e confirmada para VHC, no período de 2002 a 2005. Considerou-se transmissão vertical sorologia VHC positiva por ELISA, confirmada com PCR, após os 18 meses de vida do recém-nascido. Considerou-se fatores associados a TV: tipo de parto, tempo de rotura de membranas, amamentação, histórico de transfusões sanguíneas prévias, uso de drogas ilícitas, número de parceiros sexuais e presença de tatuagens pelo corpo. RESULTADOS: Identificou-se 58 gestantes portadoras do VHC, revelando prevalência de infecção de 0,2% (58/31.187). Das 58 pacientes, 23 (39,6%) preencheram os critérios de inclusão no estudo. A taxa de TV foi de 13% (3/23), sendo os subtipos virais mais frequentes: 1a (53%), 1b (30%), 2b (4%) e 3a (13%). Duas (8,7%) pacientes apresentaram co-infecção pelo HIV. Houve associação (p < 0,05) entre TV e carga viral elevada (> 2,5x10(6)) e entre TV e uso de drogas ilícitas pela mãe (p < 0,05). CONCLUSÕES: O presente estudo demonstra que elevada viremia materna e o uso de drogas ilícitas pela mãe associam-se a transmissão materno-fetal do VHC.

Epidemiology of the viral hepatitis B and C in female prisoners of Metropolitan Regional Prison Complex in the State of Goiás, Central Brazil

INTRODUCTION: Little information regarding hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among Brazilian female prisoners exists. This study investigated the prevalence and risk factors associated with HBV and HCV infections and identified viral genotypes among female prisoners in Goiás, Central Brazil. METHODS: Women incarcerated in the largest prison in the State of Goiás were invited to participate in the study. All female prisoners were interviewed and tested for the detection of hepatitis B surface antigen (HBsAg), antibodies against HBsAg (anti-HBs), against hepatitis B core antigen (anti-HBc), and antibody against HCV (anti-HCV) by ELISA. HBsAg and anti-HCV positive samples were tested for HBV DNA and HCV RNA and genotyped, respectively. RESULTS: Participants (n=148; 98.6%) completed the study with an overall HBV prevalence of 18.9%. Age >30 years, a low education level, sex with a sexually transmitted diseases carrier, and a male sexual partner serving in the same penitentiary were associated with HBV infections. Only 24% of the women were anti-HBs positive suggesting previous HBV vaccination. Nine female prisoners (6.1%) were anti-HCV positive. Age >40 years, injecting drug use and length of incarceration were statistically associated with anti-HCV antibodies. Five samples were HCV RNA positive and classified as genotypes 1 (subtypes 1a; n=3 and 1b; n=1) and 3 (subtype 3a; n=1). The HBsAg-reactive sample was HBV DNA positive and genotype A. CONCLUSIONS: These findings highlight the necessity of public policies to control hepatitis B and C infections and emphasize the importance of hepatitis B vaccination in prison environments.

Length and caliber of the rectosigmoid colon among patients with Chagas disease and controls from areas at different altitudes

Introduction In this study, we investigated radiological changes in the sigmoid colon in chagasic patients by comparing their colon lengths and caliber with those of non-chagasic living in the same region and non-chagasic living at high altitudes. Methods A total of 317 individuals were evaluated using clinical, serological and radiological methods and divided into three groups: 1) one hundred and nine non-chagasic individuals from Uberaba, Brazil; 2) sixty-one non-chagasic from Puno, Peru; 3) one hundred forty-seven chagasics examined in Uberaba, being 62 without megacolon (3A), 72 with megacolon (3B) and 13 with doubtful diagnosis of megacolon (3C). Results In group 2, the sigmoid colon had a significantly larger caliber (p=0.001) and the rectosigmoid colon was longer (p<0.001) than group 1. In subgroup 3A, the sigmoid colon (p<0.001) and rectum (p<0.001) had a significantly larger caliber and the rectosigmoid was longer (p<0.001) than that of the non-chagasic individuals. In subgroup 3B, the rectosigmoid was longer in all patients, and the caliber of the sigmoid was significantly larger than that of subjects in subgroups 3A and 3C (p<0.001). Conclusions Morphometric analysis confirms that Chagas disease may increase the caliber and length of the rectosigmoid. Our results suggest that altitude, ethnicity and diet may have influenced the size and length of the rectosigmoid of andean patients.

Do differences exist between chronic hepatitis C genotypes 2 and 3?

Introduction Six genotypes of the hepatitis C virus (HCV) have been identified thus far, and their distribution is well defined. Genotype 1, which is the most prevalent worldwide, is always compared to genotypes 2 and 3, particularly in terms of treatment response. However, little is known about the differences between genotypes 2 and 3 because these genotypes are analyzed together in most studies. Therefore, the aim of this study was to evaluate differences in the clinical, epidemiological, laboratory, and histological parameters between HCV-2 and HCV-3. Methods Patients with chronic hepatitis C infected with genotypes 2 and 3 were studied retrospectively and compared according to clinical, laboratory, and histological aspects. Hepatitis C virus-ribonucleic acid (HCV-RNA) was analyzed quantitatively by TaqMan® real-time PCR, and the HCV genotype was determined by sequencing the 5′-untranslated region. Results A total of 306 patients with chronic HCV-2 (n=50) and HCV-3 (n = 256) were studied. Subtype 2b (n=17/50) and subtype 3a (n=244/256) were the most prevalent among patients infected with HCV-2 and HCV-3, respectively. The mean age was 47 ± 10 years, and there was a predominance of men in the group studied (61%). Comparative analysis between HCV-2 and HCV-3 showed a younger age (p=0.002), less prevalence of arterial hypertension (p=0.03), higher serum albumin levels (p=0.01), more advanced stage of liver fibrosis (p=0.03), and higher frequency of steatosis in patients with HCV-3 (p=0.001). After multivariate regression analysis, all the variables, except serum albumin, remained as variables associated with HCV-3 in the final model. Conclusions Clinical and histological differences exist between HCV-2 and HVC-3, which suggests the need for separate analyses of these genotypes.