Orthotopic liver transplantation (OLT) is an effective treatment for patients with advanced primary biliary cirrhosis (PBC). We have conducted a retrospective analysis of 400 consecutive patients transplanted for PBC between 1983 and 1999. Mean follow-up was 56 months. The proportion of patients grafted for PBC fell progressively, from 35% in 1990 (n ‫؍‬ 80) to 21% in 1999 (n ‫؍‬ 111); comparison of patients grafted in the 2 decades showed that the median age increased from 53 to 56 years and the median serum bilirubin at transplantation fell from 270 mol/L to 132 mol/L. The overall actuarial patient and graft survival at 1, 5, and 10 years is 83%, 78%, and 67% and 82%, 75%, and 61%, respectively. The net gain in 5-year survival compared with predicted survival in the absence of transplantation fell from 37% (range, 82%-90%) to 16% (range, 91%-99%). Multiple organ failure (16.1%) and sepsis (9.6%) were the major causes of early deaths (<6 months). Recurrent PBC, diagnosed on allograft histology, was found in 68 (17%) patients, at a mean time of 36 months. We were unable to identify any pretransplantation donor or recipient factor, which identified those patients at risk of recurrence, although recurrence was much earlier and more frequently seen in patients receiving tacrolimus (P ‫؍‬ .04). PBC remains a good indication for liver transplantation, with excellent survival rates. The age at transplantation increased although patients tended to be grafted earlier. Survival rates have increased although there is a reduction in the survival benefit. Recurrence may be common, but does not seem to affect medium-term graft survival. (HEPATOLOGY 2001;33:22-27.)Orthotopic liver transplantation (OLT) in humans was first successfully reported by Starzl in 1968 1 ; in the early years, few patients were transplanted and survival rates were poor. With increasing experience; better selection; improved surgical, anesthetic, and microbiological techniques; and the introduction of potent immunosuppressive agents, results have improved considerably. As results have improved, patients have been offered transplantation when they are less ill and more likely to withstand the stresses of the procedure and the postoperative period.Primary biliary cirrhosis (PBC) has been one of the most common indications for liver transplantation in adults. 2 Although the pathogenesis remains uncertain and medical therapy, at best, only slows progression of the disease, the natural history is well understood and there are several prognostic models that have been developed to predict not only survival in the absence of transplantation but also survival after transplantation. 3,4 The indications for transplantation are relatively well defined: either a poor quality of life, usually because of intractable lethargy or pruritus, or an anticipated length of life less than 1 year. 5

Esse trabalho descreve um experimento simples e de fácil execução, destinado ao estudo da transferência de calor e massa por meio de uma aula prática. Tal estudoé realizado a partir da fusão de uma placa de gelo, ao ar ambiente, e com base na avaliação quantitativa do calor transferido por radiação, convecção e condensação de vapor d água sobre a superfície dessa placa. Os valores teóricos, previstos a partir de equações relativas a esses processos de transferência de calor e massa, são comparados com dados experimentais relativosà taxa mássica de fusão dessa placa. A facilidade na execução dos ensaios e a simplicidade do equipamento empregado torna esse experimento uma atividade prática de fácil implementação em disciplinas que tratam da transferência de calor e massa. Além disso, a concordância entre valores teórico e experimental da taxa de transferência de calor e massa, e a metodologia empregada na análise e quantificação dessa taxa, viabilizam o experimento proposto como uma ferramenta pedagógica eficiente para o estudo desse tema. Palavras-chave: transferência de calor e massa, fusão de uma placa de gelo, radiação, convecção, condensação de vapor d'água.This work describes a simple and easy-to-perform experiment, destined to the study of the heat and mass transfer by means of a practical class. This study is carried out from the melting of an ice sheet into ambient air and based on the quantitative evaluation of the heat transferred by radiation, convection and condensation of water vapor on the surface of that plate. The theoretical values, predicted from equations related to these processes of heat and mass transfers, are compared with experimental data concerning the melting mass rate of this plate. The ease of running the tests and the simplicity of the equipment employed makes this experiment a practical activity that is easy to implement in disciplines dealing with heat and mass transfer. In addition, the agreement between theoretical and experimental values of the heat and mass transfer rate, and the methodology used in the analysis and quantification of this rate, make feasible the proposed experiment as an efficient pedagogical tool to study this subject.

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Liver transplantation is now widely recognised as an effective treatment option for patients with advanced liver disease. Many units now achieve greater than 85% survival at 1 year, with the majority of patients having a high quality of life. The maintenance of a high quality of life requires careful clinical management to ensure that the continued maintenance of excellent liver graft function is not achieved at the expense of immunosuppressive drug complications or morbidity. Acute liver rejection will occur in between 30 to 45% of patients, although with modern immunosuppressive protocols, usually combining one of the calcineurin agents, either cyclosporin or tacrolimus, with both azathioprine and corticosteroids (prednisolone) ensures that relatively few grafts are lost from severe acute rejection. While the incidence and severity of acute rejection may be one factor in raising the risk of chronic rejection, it may not be the principal one in many patients. It is important to recognise that the frequency of rejection also varies with the primary underlying liver disease, with patients with hepatitis B or alcoholic liver disease having relatively low rejection rates, compared with patients with primary biliary cirrhosis (PBC) or primary sclerosing cholangitis (PSC), which range between 20 to 70%. Chronic rejection will account for some 5% of grafts lost in the first 3 to 5 years. Indeed, there is some evidence that the incidence of chronic rejection is actually declining over the past few years. While the reason for this apparent decline is uncertain, and it could relate to better immunosuppression management, or more likely to the growing recognition that chronic graft dysfunction may be due to recurrent liver disease, such as autoimmune hepatitis, PBC, PSC, or recurrent hepatitis C. The differentiation of recurrent primary liver disease from chronic rejection can prove to be very difficult in clinical practice. Thus, the clinician must carefully monitor liver and graft function, evaluate any biochemical changes, and try to reach a clear diagnosis before considering any modification of immunosuppressive schedules.

Nesse trabalho é descrito um experimento quantitativo destinado a avaliar a transferência de calor durante o resfriamento de um cilindro de aço e comparar os resultados experimentais com valores previstos em modelos de convecção e radiação do calor. Além de executar os ensaios, o aluno é requisitado a confeccionar uma planilha eletrônica que detalha os cálculos realizados e avalia a consistência dos resultados. O experimento foi concebido para ser facilmente implementado em aulas práticas de cursos de graduação; e, nesse intuito, buscou-se utilizar materiais e equipamentos que viabilizem a realização de ensaios simples e de fácil execução. Os resultados obtidos são satisfatórios e propiciam uma análise quantitativa sobre os mecanismos envolvidos na transferência de calor num sistema físico real.

Introduction: Single-nucleotide polymorphisms (SNPs) associated with hepatitis C virus (HCV) clearance were identified near the IL28B gene. Coinfection by the human immunodeficiency virus (HIV) influences the course of HCV contributing to liver damage. Nevertheless, little is known about the relationship between these SNPs and HCV/HIV coinfection. Our aim was to estimate the frequencies of the allelic and genotypic variants of the IL28B polymorphisms rs12979860 (C/T) and rs8099917 (T/G) and their possible association with the establishment of HCV infection.Methodology: A total of 199 non-infected controls and 230 patients with chronic hepatitis C, including 53 coinfected with HIV, participated in the study. Genotyping consisted of polymerase chain reaction and subsequent analysis of the restriction patterns resulting from exposure to endonucleases.Results: Among the controls with established results, 47.4% (90/190) exhibited the rs12979860 CC genotype, 43.7 CT, and 8.9% TT, whereas 29.1% (66/227), 51.5%, and 19.4% of the patients exhibited the CC, CT, and TT genotypes, respectively. With respect to rs8099917, 66.8% (133/199) of the controls exhibited the TT genotype, 31.2% TG, and 2.0% GG, whereas 56.1% (129/230), 40.9%, and 3.0% of the patients exhibited the TT, TG, and GG genotypes, respectively.Conclusion: The frequencies of the rs12979860 C allele and CC genotype and of the rs8099917 T allele and TT genotype were significantly higher among controls compared with patients, thus confirming the suggested protective effect against HCV infection. No significant difference was observed in the genotype and allelic distributions between the mono- and coinfected patients.

No abstract

Resumo -O artigo descreve a construção de um tanque hidráulico para o cálculo da perda de carga em dutos cilíndricos retos e a execução dos ensaios. O tanque possui estrutura simples, baixo custo, robustez e versatilidade necessárias para a realização de ensaios de fácil execução, baseados no registro dos tempos associados à variação da altura da coluna de água num tubo vertical. A utilização deste equipamento em aulas experimentais mostrou-se muito eficaz, possibilitando a comprovação de resultados teóricos a partir da utilização de modelos reais. Os resultados obtidos são apresentados em planilhas eletrônicas, cuja elaboração baseou-se na aplicação dos princípios de conservação de massa e energia no escoamento de fluidos viscosos, e nas equações de perda de carga distribuída e localizada. O experimento proposto constitui uma ferramenta pedagógica interessante, tendo em vista que sua execução requer a participação ativa dos alunos na realização dos ensaios e na execução de cálculos. A rotina de cálculos, visando comparar valores experimentais perda de carga obtidos experimentalmente com valores teóricos, abrange uma sé-rie de conceitos e equações da Mecânica dos Fluidos, propiciando que a aprendizagem desse conteúdo seja feita a partir de um problema real. Palavras-chave -Perda de carga. Tanque hidráulico. Mecânica dos fluidos. Abstract -The article describes the construction of a hydraulic tank designed for head loss calculation in straight cylindrical pipeline and the essays execution.The tank has low cost, simple structure, robustness and versatility required for carrying out easy execution tests, upon the recording of the time associated with changes in height of the water column in a vertical tube. The use of this equipment in practical lessons was very effective, engaging students in carrying out the tests and performing calculations. The obtained results were satisfactory and presented on spreadsheets, whose development consists on applying the principles of the mass and energy conservation in the flow of viscous fluids, as well as equations for continuous and local head losses. This experimental activity is an interesting pedagogical tool, since its implementation requires the active participation of students in carrying out tests calculations. The routine of calculations, aiming to compare head losses experimentally obtained with theoretical values, covers many concepts and equations of Fluid Mechanics, providing an opportunity for learning this subject upon the analysis of a real problem.