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Bio-energy systems with carbon capture and storage (BECCS) will be essential if countries are to meet the gas emission reduction targets established in the 2015 Paris Agreement. This study seeks to carry out a thermodynamic optimization and analysis of a BECCS technology for a typical Brazilian cogeneration plant. To maximize generated net electrical energy (MWe) and carbon dioxide CO2 capture (Mt/year), this study evaluated six cogeneration systems integrated with a chemical absorption process using MEA. A key performance indicator (gCO2/kWh) was also evaluated. The set of optimal solutions shows that the single regenerator configuration (REG1) resulted in more CO2 capture (51.9% of all CO2 emissions generated by the plant), penalized by 14.9% in the electrical plant's efficiency. On the other hand, the reheated configuration with three regenerators (Reheat3) was less power-penalized (7.41%) but had a lower CO2 capture rate (36.3%). Results showed that if the CO2 capture rates would be higher than 51.9%, the cogeneration system would reach a higher specific emission (gCO2/kWh) than the cogeneration base plant without a carbon capture system, which implies that low capture rates (<51%) in the CCS system guarantee an overall net reduction in greenhouse gas emissions in sugarcane plants for power and ethanol production.

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BACKGROUND AND AIMS: Patients with decompensated cirrhosis are at increased risk of mortality, even in absence of ACLF. The CLIF-C AD score (CLIF-C ADs) was proposed as a prognostic score but lacks sufficient validation. Our aim was to describe clinical characteristics and hospital evolution according to score groups and evaluate prognostic capability of CLIF-C ADs alone or in combination with other scores. METHODS: Two hundred and sixty-six patients (55 ± 14 years, ascites in 63%, MELD 14 ± 5) were included, and classified as high, intermediate and low CLIF-C ADs in 13, 60 and 27% of cases. Development of new complications of cirrhosis during hospitalization and survival at 3 months were evaluated. RESULTS: Patients with high CLIF-C ADs had more severe systemic inflammation parameters and higher frequency of organ dysfunction. CLIF-C ADs ≥ 60, when compared to intermediate and low groups, was associated with higher incidence of complications of cirrhosis (90% vs 70% and 49%, p < 0.001) and lower survival (93%, 80% and 50%, p < 0.0001). In multivariate analysis, CLIF-C ADs, ascites and MELD were predictors of survival [(AUROC 0.76 (95% CI 0.69-0.83)]. Absence of ascites or MELD < 14 identified patients with intermediate CLIF-C ADs and good survival (89 and 84%, respectively). CONCLUSION: CLIF-C ADs predicts survival in cirrhotic patients with AD. High CLIF-C ADs is associated with higher frequency of organ dysfunction, increased risk of new complications of cirrhosis and high short-term mortality. On the contrary, individuals with low CLIF-C ADs, as well as those with intermediate score without ascites or with low MELD have excellent prognoses.

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BACKGROUND: Few studies have evaluated whether combination and sequential evaluation of ACLF (acute-on-chronic liver failure) and hyponatremia aids prognosis. AIMS: Describe clinical course and determine prognostic capability of assessing ACLF and hyponatremia at specific time-points. METHODS: Prospective study with inclusion of 376 patients. ACLF and hyponatremia were evaluated at days 1 and 7 and classified as persistent, transient, de novo or absent. Follow-up was 90 days. RESULTS: At inclusion, ACLF was diagnosed in 99 patients. Reversal was observed in 57 patients and was associated with lower creatinine and ACLF grade. De novo ACLF developed in 19 patients, and MELD (model of end-stage liver disease) score and lower albumin were predictive factors. Hyponatremia was present in 76 patients (persistent, transient and de novo in 27, 24 and 25 respectively). ACLF at D7 had the lowest survival compared to transient or no ACLF (21, 57 and 80%, p < 0.0001). Hyponatremia at admission was associated with low survival (35%) whereas survival was higher for de novo or absent cases (70%), p < 0.001. In multivariate analysis ACLF at D7 and hyponatremia at D1 were predictors of survival. CONCLUSION: ACLF and hyponatremia are dynamic and evaluation of both conditions at different time-points identifies patients at higher risk of short-term mortality.

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A esquistossomose constitui grave problema de saúde pública, com mais de 200 milhões de infectados no mundo. Deste total, cerca de 10% desenvolvem a forma hepatoesplênica da doença caracterizada por fibrose periportal e hipertensão porta. No passado, o diagnóstico da esquistossomose hepatoesplênica (EHE) era realizado por métodos invasivos como esplenoportografia e biópsia hepática. O estudo das alterações no sistema porta e da morfologia hepática e esplênica com métodos de imagem representou um avanço significativo no diagnóstico da doença. Os métodos mais utilizados atualmente são a ultrassonografia abdominal, a ressonância nuclear magnética e a tomografia computadorizada de abdomen. O objetivo do presente artigo é abordar as principais contribuições de cada método no diagnóstico da EHE.

Schistosomiasis is a serious public health problem with over 200 million infected worldwide. Nearly 10% of infected individuals develop the hepatosplenic form of the disease characterized by periportal fi brosis and portal hypertension. In the past, the diagnosis of hepatosplenic schistosomiasis (HHS) was performed by invasive methods such as liver biopsy and splenoportography. The study of changes in portal system and morphological aspects of liver and spleen with imaging techniques represented a significant advance in the diagnosis of the disease. The most widely used techniques are abdominal ultrasonography, magnetic resonance imaging and computed tomography of the abdomen. The aim of this article is to discuss the main contribution of each technique in the diagnosis of HHS.

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A encefalopatia hepática (EH) é um distúrbio funcional do sistema nervoso central (SNC) associado à insufi ciência hepática, de fisiopatologia multifatorial e complexa. Devido aos avanços no conhecimento sobre o manejo da EH na cirrose e na insuficiência hepática aguda (IHA), a diretoria da Sociedade Brasileira de Hepatologia (SBH) promoveu uma reunião monotemática acerca da fi siopatologia, diagnóstico e tratamento da EH, abordando aspectos controversos relacionados ao tema. Com a utilização de sistemática da medicina baseada em evidências, foram abordados o manejo da EH e da hipertensão intracraniana na IHA, o manejo da EH episódica na cirrose, as controvérsias no manejo da EH e a abordagem da EH mínima. O objetivo desta revisão é resumir os principais tópicos discutidos na reunião monotemática e apresentar recomendações sobre o manejo da síndrome votadas pelo painel de expertos da SBH.

Hepatic encephalopathy (HE) is a functional disorder of the central nervous system (CNS) associated with liver failure, either end-stage chronic liver disease or fulminant hepatic failure. Its pathogenesis remains complex and poorly understood. In view of recent advances in the management of HE, the Brazilian Society of Hepatology endorsed a monothematic meetingregarding HE in order to gather experts in the to discuss related data and to draw evidence-based recommendations concerning: management of HE and intracranial hypertension in FHF, treatment of episodic HE in cirrhosis, controversies in the management of EH including difficult to treat cases and diagnostic and treatment challenges for minimal HE. The purpose of this review is to summarize the lectures and recommendations made by the panel of experts of the Brazilian Society of Hepatology.

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BACKGROUND: The natural outcome of infection with hepatitis C virus (HCV) varies substantially among individuals. However, little is known about host and viral factors associated with a self-limiting or chronic evolution of HCV infection. METHODS: From 1 January 2001 through 31 December 2008, a consecutive series of 65 patients from Rio de Janeiro, Brazil, with a well-documented diagnosis of acute HCV infection, acquired via various routes, were enrolled in this study. Patients were prospectively followed up for a median of 40 months after the estimated date of HCV infection with serial measurements of serum alanine aminotransferase, HCV RNA, and anti-HCV antibodies. Spontaneous viral clearance (SVC) was defined as undetectable levels of HCV RNA in serum, in the absence of treatment, for 3 consecutive HCV polymerase chain reaction tests within the first 6 months of follow-up. Cox proportional hazards regression was used to identify host and viral predictors of SVC. RESULTS: The cumulative rate of SVC was 44.6% (95% confidence interval, 32.3%-57.5%). Compared with chronic HCV evolution, patients with self-limiting disease had significantly lower peak levels of anti-HCV antibodies (median, 109.0 vs 86.7 optical density-to-cutoff ratio [od/co]; P<.02), experienced disease symptoms more frequently (69.4% vs 100%; P<.001), and had lower viral load at first clinical presentation (median, 4.3 vs 0.0 log copies; P=.01). In multivariate analyses, low peak anti-HCV level (<93.5 od/co) was the only independent predictor for SVC; the hazard ratio compared with high anti-HCV levels (> or =93.5 od/co) was 2.62 (95% confidence interval, 1.11-6.19; P=.03). CONCLUSION: Our data suggest that low levels of anti-HCV antibodies during the acute phase of HCV infection are independently related to spontaneous viral clearance.

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The selection of donors for living donor liver transplantation (LDLT) is one of the most important features in this kind of surgery. The aim of this study is to describe our initial experience in the donor evaluation process. From December 2001 to January 2005, 104 donors were evaluated for 70 recipients (65 potential donors were evaluated for 39 adult recipients, and 39 donors for 31 pediatric recipients). Only 30 donors were able to donate: 13 for the adult group, and 17 for the pediatric one. In general, the utilization rate of potential donors was 28.8% (30/104). For the adult patients, 65 potential donors were seen to perform 13 LDLT, which represents a utilization rate of potential donors of 20%. For the pediatric patients, this rate was 43.6%. The exclusion criteria were clinical in 22 cases (21%), anatomical in 13 cases (13%), psychosocial in nine cases (9%), and others in 12 (12%). Death of recipients led to exclusion 18 of donors (17%). Thirty-three percent of adults and 55% of pediatric recipients who had at least one potential donor to start the evaluation process were able to identify a living donor. In conclusion, the first limit for LDLT is the rigorous donor evaluation.

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Uma vez que existe a possibilidade de ocorrer infecção cruzada através das moldagens, surgiu a idéia de se fazer a desinfecção dos materiais de moldagem antes de se vazar o gesso, segundo Laufer et al. (1996). Por se necessitar de fidelidade durante a reabilitação bucal, os métodos de desinfecção não devem alterar a dimensão das impressões dentais elastoméricas. Estudos de Drennon et al. (1989) mostram que a desinfecção de impressões elastoméricas por imersão não leva a alterações significantes nos modelos subseqüentes. Também para eles, o uso de spray desinfetante não traz deformações nos modelos de gesso feitos sobre impressões elastoméricas. Já a solução de hipoclorito de sódio sempre tende a uma expansão em comparação com controles, afirma Laufer et al. (1996)

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A intensa pressäo social em torno do "sorriso branco" com o padräo de beleza fez com que houvesse uma ampla divulgaçäo nos meios de comunicaçäo e, consequentemente, um maior interesse por parte dos pacientes em relaçäo ao tratamento do clareamento dental. O surgimento de novas técnicas e produtos acabou criando maiores dificuldades para o clínico geral em relaçäo a um correto planejamento e execuçäo de tratamentos clareadores. Este artigo, recorrendo à literatura referenciada e a experiência clínica, indica uma abordagem particular para o clareamento de manchas dentinárias de forma caseira, clínica e associada; discutindo vantagens e desvantagens destes novos métodos e produtos clareadores, bem como o passo a passo das manobras. Os produtos à base de Carbamida em gel, tanto em casa como em consultório, tem se mostrado como tendência dentro da prática clínica, usados de forma e concentraçöes variadas referentes a cada tipo de manchamento

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