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Infection by hepatitis B virus (HBV) is a worldwide public health problem. Chronic HBV infection with high viral replication may lead to cirrhosis and/or hepatocellular carcinoma. Mutant HBV strains, such as the HBV A1762T/G1764A double mutant, have been associated with poor prognosis and higher risk of the patient for developing cirrhosis and/or hepatocellular carcinoma. This study analyzed the presence of the HBV A1762T/G1764A double mutant in patients with chronic HBV and its association with clinical parameters such as viral load, aminotransferases, and HBV antigens. A total of 49 patients with chronic hepatitis B were included in the study, and the HBV A1762T/G1764A double mutant strain was detected in four samples (8.16%) by polymerase chain reaction followed by restriction fragment length analysis (PCR-RFLP). The viral load was not significantly different between patients with or without the double mutant strain (p = 0.43). On the other hand, carriers of the HBV A1762T/G1764A double mutant had higher levels of ALT (p = 0.0028), while AST levels did not differ between groups (p = 0.051). In this study, 75% of the samples with the HBV A1762T/G1764A double mutation were HBeAg negative and anti-HBe positive, reflecting seroconversion even though they still displayed high viral loads. Our study has shown that the HBV A1762T/G1764A double mutant strain circulates in Brazilian patients, and is associated with elevated levels of ALT and HBeAg seroconversion. Keywords: Hepatitis B, HBV, A1762T/G1764A mutation

The influenza virus is one of the most critical viruses in epidemiology. The 2009 pandemic was caused by a reassortment of the human–avian–swine virus with eight RNA segments responsible for all virus proteins. Segment 7 codifies for matrix proteins M1 and M2. These proteins exhibited low mutation rate because the matrix is fundamental for virion encapsidation and ion channel formation. However, hemagglutinin (HA) segment 4 is one of the most important segments for virulence and hence, is more studied. Brazil had many influenza virus infection cases just before 2009 and from 2011 to 2015, particularly in the Rio Grande do Sul (RS) State. Two hundred samples obtained during the pandemic were used for amplification and sequencing of the viral genome; a total of 19 M and 17 HA amplified segments were sequenced. Sequencing of the M fragment showed that RS has a virus origin different from that in Eastern Asia, Western Europe, USA, and Central America (Mexico and Nicaragua). All the sequences showed amantadine resistance (S31N) and one was out of the phylogenetic tree (Brazil/RS-3335/2009) due to high mutation rate. RS-3335 was the only sample obtained from a patient who died. Many migratory birds that flock to RS are from Europe, Asia, and USA, which could explain this rate of mutation. Insertions and deletions were found in the M1 protein in these samples. The HA sequences showed worldwide spread and less diversity than the M sequences in this study. The most divergent sample was Brazil/RS-3093/2009 that showed mutations in the sialic acid ligation site.

Context Hepatitis B virus (HBV) can cause fulminant hepatitis, cirrhosis and hepatocellular carcinoma, and is one of the most common causes of acute and chronic liver failure. The genetic variants of HBV can be decisive for the evolution of these diseases as well as for the election of therapy. Objectives The aim of this study was to evaluate and standardize an in house methodology based on the analysis of the melting curve polymerase chain reaction (PCR) of real-time (qPCR) to screen for genotypes A, D and F of HBV in patients from a hospital in Rio Grande do Sul, Brazil. Methods We evaluated 104 patients presumably with HBV chronic infection. Viral DNA was extracted from plasma and viral genotypes and different mutations were determined using PCR-based protocols. Results A PCR-based methodology was standardized for the analysis of genotypes A, D and F of HBV. The technique was based in a nested PCR with the final step consisting of a multiplex real-time PCR, using the melting curve as a tool for the differentiation of fragments. A higher frequency of genotype D (44.4%), followed by genotype A (22.2%) and genotype F (3.7%) was observed. Conclusion The standardized assay, a nested PCR-multiplex qPCR using specific primers, provides a rapid and accurate method for the differentiation of HBV genotypes that are more frequent in Southern Brazil – A, D and F. This method can be applied in the clinical practice. Contexto O vírus da hepatite B pode causar hepatite fulminante, cirrose e carcinoma hepatocelular, sendo uma das causas mais frequentes de doença aguda e crônica do fígado. As variantes genéticas do VHB podem ser determinantes para a evolução da doenças assim como para a eleição da terapêutica. Objetivos O objetivo deste estudo foi padronizar e avaliar uma metodologia “in house”, através da utilização da curva de melting de reação em cadeia da polimerase (PCR) em tempo real (qPCR), como rastreamento para análise dos genótipos A, D e F do vírus da hepatite B em pacientes do Rio Grande do Sul. Métodos Foram avaliados 104 pacientes supostamente com infecção crônica pelo VHB. O DNA foi extraído com kit comercial, os genótipos e as mutações foram determinados utilizando diferentes protolocos baseados em PCR. Resultados Foi padronizada uma metodologia baseada em PCR para a análise dos genótipos A, D e F do VHB. A técnica consistiu de uma PCR Nested incluindo uma etapa final de PCR em tempo real Multiplex, utilizando a curva de melting como ferramenta para a definição dos fragmentos. Foi observada uma maior frequência do genótipo D (44,4%), seguido do genótipo A (22,2%) e do genótipo F (3,7%) na amostra analisada. Conclusão O ensaio padronizado fornece um método rápido e preciso para diferenciar genótipos do VHB mais frequentes no sul do Brasil – A, D e F – usando um PCR Nested Multiplex com primers específicos, o qual apresenta potencial aplicação na prática clínica.

OBJECTIVE: To evaluate structural alterations of the lung in rats with diabetes mellitus (DM), by quantifying oxidative stress and DNA damage, as well as to determine the effects that exogenous superoxide dismutase (SOD) has on such alterations. METHODS: A controlled experimental study involving 40 male Wistar rats, divided into four groups (10 animals each): control; SOD-only (without DM but treated with SOD); IDM-only (with streptozotocininduced DM but untreated); and IDM+SOD (with streptozotocin-induced DM, treated with SOD). The animals were evaluated over a 60-day period, day 0 being defined as the day on which the streptozotocin-injected animals presented glycemia > 250 mg/dL. The SOD was administered for the last 7 days of that period. At the end of the study period, samples of lung tissue were collected for histopathological analysis, evaluation of tissue oxidative stress, and assessment of DNA damage. RESULTS: There were no significant differences among the groups regarding DNA damage. In the IDM-only group, there was a significant increase in the extracellular matrix and significantly greater hyperplasia of the capillary endothelium than in the SOD-only and control groups. In addition, there were significant changes in type II pneumocytes and macrophages, suggesting an inflammatory process, in the IDM-only group. However, in the IDM+SOD group, there was a reduction in the extracellular matrix, as well as normalization of the capillary endothelium and of the type II pneumocytes. CONCLUSIONS: Exogenous SOD can reverse changes in the lungs of animals with induced DM.

The aim of this study was to evaluate NF-kB during 5-fluorouracil (FU)-induced oral mucositis and ascertain whether photobiomodulation (PBM), as a preventive and/or therapeutic modality, influences this transcription factor. Ninety-six male golden Syrian hamsters were allocated into four groups: control (no treatment); PBM therapeutic, PBM preventive, and PBM combined. Animals received an injection of 5-FU on days 0 and 2. On days 3 and 4, the buccal mucosa was scratched. Irradiation was carried out using a 660-nm, 40-mW diode laser at 6 J/cm(2) during 6 s/point, 0.24 J/point, for a total dose of 1.44 J/day of application. Animals were euthanized on days 0, 5, 10, and 15 (n=6). Buccal mucosa was removed for protein quantification by Western blot. Clinical analysis revealed that PBM groups exhibited less mucositis than controls on day 10. Control animals exhibited lower levels of NF-kB during mucositis development and healing. The preventive and combined protocols were associated with higher NF-kB levels at day 5; however, the therapeutic group had higher levels at days 10 and 15. These findings suggest that the preventive and/or therapeutic PBM protocols reduced the severity of oral mucositis by activating the NF-kB pathway.

Background Evidences have been highlighted the relationship among metabolic syndrome, chronic low-grade inflammation, oxidative stress and several diseases. In this sense, the aim of this study was to investigate the effects of aerobic exercise training on oxidative stress and inflammatory parameters on women with metabolic syndrome (MS). Methods Twenty-three untrained women (51.86 ± 6.58 years old, BMI 30.8 ± 4.3 kg/m2) completed a 12-week treadmill exercise training, without modifications on dietary pattern. Advanced oxidation protein products (AOPP), thiobarbituric acid-reactive substances (TBARS), total thiol content (T-SH) and nitrite and nitrate (NOx) levels were assessed in plasma while the levels of interleukin-1 beta (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor alpha (TNF-α) and interferon-gamma (IFN-γ) were evaluated in the serum. The RNA expression (mRNA) of IL-1β, IL-10, TNF-α, IFN-γ, insulin receptor substrate 2 (IRS-2) and matrix metalloproteinase-9 (MMP-9) were performed inperipheral blood mononuclear cells (PBMC) of a subset with eight women with MS using real real-time polymerase chain reaction (qPCR). Results The intervention resulted in decreased serum levels of IL-1β, IL-6, TNF-α, IFN-γ, AOPP and TBARS, besides increased levels of IL-10 and T-SH (P < 0.001). NOx concentrations were unchanged, similarly to mRNA expressions quantified in PBMC. Conclusions Twelve weeks of AT improved systemic oxidative stress and inflammatory biomarkers in women with MS, although PBMC mRNA expression for inflammatory pathways appeared to be unchanged. This may indicate that AT induced beneficial effects not only in physical fitness but also on health promotion through decreased oxidative damage and proinflammatory status.

Croton cajucaraBenth is a plant found in Amazonia, Brazil and the bark and leaf infusion of this plant have been popularly used to treat diabetes and hepatic disorders. The present study was designed to evaluate the oxidative stress as well as the therapeutic effect ofCroton cajucaraBenth (1.5 mL of theC. cajucaraextract i.g.) in rats with streptozotocin-induced diabetes.Croton cajucaraBenth was tested as an aqueous extract for its phytochemical composition, and its antioxidant activityin vitrowas also evaluated. Lipid peroxidation and superoxide dismutase, catalase, and glutathione reductase activities were measured in the hepatic tissue, as well as the presence activation of p65 (NF-κB), through western blot. Phytochemical screening ofCroton cajucaraBenth detected the presence of flavonoids, coumarins and alkaloids. The extract exhibited a significant antioxidant activity in the DPPH-scavenging and the hypoxanthine/xanthine oxidase assays. Liver lipid peroxidation increased in diabetic animals followed by a reduction in theCroton-cajucara-Benth-treated group. There was activation of p65 nuclear expression in the diabetic animals, which was attenuated in the animals receiving theCroton cajucaraBenth aqueous extract. The liver tissue in diabetic rats showed oxidative alterations related to the streptozotocin treatment. In conclusion theCroton cajucaraBenth aqueus extract treatment effectively reduced the oxidative stress and contributed to tissue recovery.

To evaluate structural alterations of the lung in rats with diabetes mellitus (DM), by quantifying oxidative stress and DNA damage, as well as to determine the effects that exogenous superoxide dismutase (SOD) has on such alterations.A controlled experimental study involving 40 male Wistar rats, divided into four groups (10 animals each): control; SOD-only (without DM but treated with SOD); IDM-only (with streptozotocininduced DM but untreated); and IDM+SOD (with streptozotocin-induced DM, treated with SOD). The animals were evaluated over a 60-day period, day 0 being defined as the day on which the streptozotocin-injected animals presented glycemia250 mg/dL. The SOD was administered for the last 7 days of that period. At the end of the study period, samples of lung tissue were collected for histopathological analysis, evaluation of tissue oxidative stress, and assessment of DNA damage.There were no significant differences among the groups regarding DNA damage. In the IDM-only group, there was a significant increase in the extracellular matrix and significantly greater hyperplasia of the capillary endothelium than in the SOD-only and control groups. In addition, there were significant changes in type II pneumocytes and macrophages, suggesting an inflammatory process, in the IDM-only group. However, in the IDM+SOD group, there was a reduction in the extracellular matrix, as well as normalization of the capillary endothelium and of the type II pneumocytes.Exogenous SOD can reverse changes in the lungs of animals with induced DM.

CONTEXT: In recent years the hepatitis B virus (HBV) genotyping has been considered a relevant factor in the natural history of the disease. OBJECTIVE: To determine hepatitis B virus genotypes and its epidemiological and clinical implications, in a cohort of patients in a hospital in Porto Alegre, South of Brazil. Methods - Sixty seven patients with HBV chronic infection markers who were being treated at ''Complexo Hospitalar Santa Casa'', in Porto Alegre, RS, Brazil, were evaluated. Demographic and epidemiological data were collected from these group of patients by following a standard protocol and ALT and HBeAg were determined. The genotypes and subtypes were determined by in-house PCR and, finally, the samples were sequenced. The level of significance used was 5%. RESULTS: The qualitative analysis for HBV-DNA by PCR was positive in 79.1% of the samples (53/67). The genotype was determined in all positive VHB-DNA samples and the genotypes A (34%), D (60.4%) and F (5.4%) as well as the subtypes adw, ayw and adw4 were found. No significant correlation was found between the hepatitis B virus genotypes and demographic variables considered as risk factors for hepatitis B virus infection. There was also no correlation between the genotypes and the serological and laboratory variables related to liver disease. CONCLUSION: We concluded that the most prevalent genotype found was D. However, further studies are needed to allow us to evaluate the implications of genetic variability in the clinical evolution of HBV carriers.CONTEXTO: Nos últimos anos a genotipagem do vírus da hepatite B (VHB) tem sido considerado fator relevante para a história natural da doença. OBJETIVOS: Determinar os genótipos do VHB e suas implicações clínicas e epidemiológicas, em uma coorte de pacientes em um hospital de Porto Alegre, RS, sul do Brasil. MÉTODOS: Foram avaliados 67 pacientes com marcadores de infecção crônica pelo VHB que estavam sendo tratados no Complexo Hospitalar Santa Casa de Porto Alegre, RS. Foi aplicado um protocolo com dados demográficos e epidemiológicos dos pacientes, e AgHBe e ALT foram determinadas. Os genótipos e subtipos foram determinados por PCR in-house e, finalmente, as amostras foram sequenciadas. O nível de significância utilizado foi de 5%. RESULTADOS: A análise qualitativa de VHB-DNA por PCR foi positiva em 79,1% das amostras (53/67). O genótipo foi determinado em todas as amostras de VHB-DNA positivo. A análise demonstrou a presença dos genótipos A (34%), D (60,4%) e F (5,4%). Foram encontrados os seguintes subtipos: adW, ayw e adw4. Nenhuma correlação significativa foi encontrada entre os genótipos do VHB e as variáveis demográficas estudadas como fator de risco para infecção pelo VHB, e com os exames sorológicos e laboratoriais de doença hepática. CONCLUSÃO: O genótipo mais prevalente encontrado foi o D. No entanto, mais estudos são necessários para que se possa avaliar as implicações da variabilidade genética na evolução clínica de portadores do VHB.

To evaluate the effects of the use of gadolinium chloride before and after induction of acute pancreatitis with sodium taurocholate 3% in rats.Wistar rats were divided into five groups: SF--control with saline intra-ductal and IV; GD control with saline intra-ductal and gadolinium chloride IV; TS--with AP control induced by sodium taurocholate 3% and saline IV; GDTS--pre-treatment with GD (24 hours before the induction of AP) and TSGD--treatment with GD (1 hour after the induction of AP). Analysis was made in serum amylase, transaminases and TNF-α; determination of the MPO activity in lung tissue, lung and pancreatic histology.The number of dead animals before the end of the experiment was significantly higher in TSGD (P = 0.046). The scores of pancreatitis and lung damage were higher in the groups that used sodium taurocholate compared to groups with intra-ductal infusion of saline solution. There were no differences in other variables studied when comparing TS, GDTS and TSGD groups.The benefits with the use of gadolinium chloride as a prophylactic and therapeutic drug were not demonstrated.

Diabetes mellitus is an endocrine/metabolic disorder characterized by hyperglycemia. Its impact on the respiratory system is characterized by functional changes and alterations in gas exchange. The objective of this study was to evaluate the increase in oxidative stress and the potential damages to the lung structure in an experimental model of streptozotocin-induced diabetes. We conducted histological, biochemical and blood gas analyses in the lungs of diabetic rats. We concluded that the effects of experimental diabetes mellitus include oxidative stress, structural changes in the lung tissue and altered gas exchange.

O diabetes mellitus é uma desordem endócrino-metabólica caracterizada pela hiperglicemia. O seu impacto no sistema respiratório é caracterizado por alterações funcionais e na troca gasosa. O objetivo deste estudo foi avaliar o aumento do estresse oxidativo e os possíveis danos na estrutura pulmonar no modelo de diabetes experimental induzido por estreptozotocina. Foram realizadas análises histológicas, bioquímicas e gasométricas no pulmão de ratos diabéticos. Concluiu-se que o estresse oxidativo está presente no diabetes mellitus experimental e que ocorrem alterações estruturais no tecido pulmonar, bem como alterações na troca gasosa. Diabetes mellitus is an endocrine/metabolic disorder characterized by hyperglycemia. Its impact on the respiratory system is characterized by functional changes and alterations in gas exchange. The objective of this study was to evaluate the increase in oxidative stress and the potential damages to the lung structure in an experimental model of streptozotocin-induced diabetes. We conducted histological, biochemical and blood gas analyses in the lungs of diabetic rats. We concluded that the effects of experimental diabetes mellitus include oxidative stress, structural changes in the lung tissue and altered gas exchange.

Background: Liver cancer is one of the most common malignancies in the world and at the moment, there is no drug intervention effective for the treatment of liver tumours. Investigate the effect of N-acetylcysteine (NAC), which has been studied for its antitumoural properties, on the toxicity of hepatocarcinoma (HCC) cells in vitro when used with the drug interferon alpha-2A (IFN), which is used clinically to treat HCC. Results: NAC, IFN and NAC plus IFN reduced cell viability, as determined by MTT assay. More importantly, NAC potentiates the cytotoxic effect of IFN, with the best response achieved with 10 mM of NAC and 2.5 x 104 of IFN. These results were confirmed by Annexin/PI staining through flow cytometry and morphologic analyses. Co-treatment reduced the expression of the nuclear transcription factor kappa-B (NF-kB). In a similar way to NAC, RNAi against p65 potentiated the toxic effect of IFN, suggesting that, indeed, NAC may be enhancing the effect of IFN through inhibition of NF-kB. Conclusions: Our results support the notion that NAC may be an important drug for the treatment of liver tumours as primary or adjuvant therapy. IFN has a limited clinical response, and therefore, the anti-proliferative properties of NAC in the liver should be explored further as an alternative for non-responders to IFN treatment.