Immunobiology of liver dendritic cells

Dendritic cells (DC) are rare, bone marrow-derived antigen-presenting cells that play a critical role in the induction and regulation of immune reactivity. In this article, we review the identification and characterization of liver DC, their ontogenic development, in vivo mobilization and population dynamics. In addition, we discuss the functions of DC isolated from liver tissue or celiac lymph, or propagated in vitro from liver-resident haemopoietic stem/progenitor cells. Evidence concerning the role of DC in viral hepatitis. liver tumours, autoimmune liver diseases, granulomatous inflammation and the outcome of liver transplantation is also discussed.

Vaccination, atherosclerosis and systemic lupus erythematosus

Atherosclerosis is an inflammatory disease, leading to the formation of pro-inflammatory and pro-oxidative lipids that generate an immune response. Several antigens have been shown to activate the immune response and affect the development of atherogenesis. Systemic lupus erythematosus is an autoimmune and inflammatory disease strongly associated with premature development of atherosclerotic plaques. Modulation of the immune system could represent a useful approach to prevent and/or treat atherosclerosis. A vaccination-based approach might be a useful, effective tool in the modern arsenal of cardiovascular therapies and could be used on a large scale at a low cost. In non-systemic lupus erythematosus populations, vaccines against oxidized low-density lipoprotein, beta-2-glycoprotein I, heat shock proteins, lipoproteins, cholesterol, molecules involved in cholesterol metabolism, and other molecules (CD99, vascular endothelial growth factor-receptor, and interleukin-2) have been tested, with promising results. However, there are no studies of vaccination against atherosclerosis in systemic lupus erythematosus. Lupus (2009) 18, 1209-1212.

Molecular basis of infantile reversible cytochrome c oxidase deficiency myopathy

Childhood-onset mitochondrial encephalomyopathies are usually severe, relentlessly progressive conditions that have a fatal outcome. However, a puzzling infantile disorder, long known as `benign cytochrome c oxidase deficiency myopathy` is an exception because it shows spontaneous recovery if infants survive the first months of life. Current investigations cannot distinguish those with a good prognosis from those with terminal disease, making it very difficult to decide when to continue intensive supportive care. Here we define the principal molecular basis of the disorder by identifying a maternally inherited, homoplasmic m.14674T > C mt-tRNA(Glu) mutation in 17 patients from 12 families. Our results provide functional evidence for the pathogenicity of the mutation and show that tissue-specific mechanisms downstream of tRNA(Glu) may explain the spontaneous recovery. This study provides the rationale for a simple genetic test to identify infants with mitochondrial myopathy and good prognosis.

Pore Formation Triggered by Legionella spp. Is an Nlrc4 Inflammasome-Dependent Host Cell Response That Precedes Pyroptosis

Legionella pneumophila, the etiological agent of Legionnaires disease, is known to trigger pore formation in bone marrow-derived macrophages (BMMs) by mechanisms dependent on the type IVB secretion system known as Dot/Icm. Here, we used several mutants of L. pneumophila in combination with knockout mice to assess the host and bacterial factors involved in pore formation in BMMs. We found that regardless of Dot/Icm activity, pore formation does not occur in BMMs deficient in caspase-1 and Nlrc4/Ipaf. Pore formation was temporally associated with interleukin-1 beta secretion and preceded host cell lysis and pyroptosis. Pore-forming ability was dependent on bacterial Dot/Icm but independent of several effector proteins, multiplication, and de novo protein synthesis. Flagellin, which is known to trigger the Nlrc4 inflammasome, was required for pore formation as flaA mutant bacteria failed to induce cell permeabilization. Accordingly, transfection of purified flagellin was sufficient to trigger pore formation independent of infection. By using 11 different Legionella species, we found robust pore formation in response to L. micdadei, L. bozemanii, L. gratiana, L. jordanis, and L. rubrilucens, and this trait correlated with flagellin expression by these species. Together, the results suggest that pore formation is neither L. pneumophila specific nor the result of membrane damage induced by Dot/Icm activity; instead, it is a highly coordinated host cell response dependent on host Nlrc4 and caspase-1 and on bacterial flagellin and type IV secretion system.

Effect of Gender on Swallow Event Duration Assessed by Videofluoroscopy

There are data suggesting that women swallow liquids at a lower flow rate and ingest smaller volumes in each swallow than men. Our objective in this work was to compare swallowing in asymptomatic men and women by videofluoroscopy. We studied 18 men [age = 33-77 years, mean = 61 (10) years] and 12 women [age = 29-72 years, mean = 53 (15) years] who swallowed in duplicate 5 and 10 ml of liquid and paste barium boluses. None of the volunteers had dysphagia, neurologic diseases, or oral, pharyngeal, or esophageal diseases. The videofluoroscopic examination showed that for the 5-ml bolus, women had a longer oropharyngeal transit [liquid: men, 0.63 (0.21) s, women, 0.88 (0.39) s; paste: men, 0.64 (0.35) s, women, 0.94 (0.58) s], longer oral transit [liquid: men, 0.41 (0.21) s, women, 0.59 (0.35) s; paste: men, 0.39 (0.28) s, women, 0.59 (0.42) s], and longer pharyngeal clearance [liquid: men, 0.36 (0.11) s, women, 0.45 (0.16) s; paste: men, 0.42 (0.25) s, women, 0.56 (0.27) s] compared with men (p < 0.05). We conclude that there are differences in swallowing between men and women, with women having a longer oropharyngeal transit than men for a 5-ml bolus.

Role of LMP1 in immune control of EBV infection

The Epstein-Barr virus (EBV) encoded latent membrane protein (LMP1) plays a crucial role in the long-term persistence of this virus within the cells of the immune system. Not only is this protein critical for the transformation of resting B cells by EBV, it also displays pleiotropic effects on various cellular proteins expressed in the host cell. These include up-regulation of expression of B cell activation antigens, adhesion molecules and various components of the antigen processing pathway. Here we discuss how LMP1 acts like an expression 'switch' which, depending on the stage of EBV infection, manoeuvres various pathways that either modulate the immune system towards or against its survival.

Determinação de autoanticorpos em doentes com suspeita de hepatite autoimune e cirrose biliar primária

O diagnóstico de doença hepática autoimune em doentes com patologia hepática implica a exclusão de outras causas de lesão hepática como vírica, alcoólica, tóxica, devido a alterações genéticas ou metabólicas, esteatose hepática não alcoólica e uma criteriosa avaliação de dados clínicos, bioquímicos, histológicos e colangiográficos especificas destas patologias (Invernizzi et al 2007) O diagnóstico e tratamento precoces destas patologias são fundamentais para a prevenção da alta morbilidade e mortalidade associada a estes doentes. O despiste de patologia hepática autoimune assenta na utilização de testes serológicos para a deteção de autoanticorpos associados a estas patologias. O conhecimento destes testes e a interpretação dos resultados obtidos revelam-se fundamentais para o diagnóstico ou exclusão destas doenças (Beuers 2005). Deste modo, foi objetivo deste trabalho a pesquisa e identificação de autoanticorpos em uso clínico: ANA, AMA, AML, ANCA, Anti-SLA/LP, anti-LKM, anti-LC1 e anti-actina F, em doentes com suspeita de HAI e CBP em que foi excluída causa vírica, alcoólica e tóxica. O trabalho incidiu particularmente na comparação dos resultados do perfil de autoanticorpos de pedidos feitos ao exterior com os resultados obtidos recorrendo à utilização de um novo kit de imunoblot, e assim determinar a relevância da introdução da pesquisa dos novos autoanticorpos e avaliar a relação custo/benefício da implementação do kit BlueDot liver da D-tek® na rotina laboratorial do serviço de Patologia Clínica do Hospital Pedro Hispano. Os resultados encontrados foram de 100% de concordância entre os métodos de imunofluorescência indireta e imunoblot, e Elisa e Imunoblot. Deste modo seria uma boa estratégia a implementação desta última técnica na rotina laboratorial uma vez que proporciona uma rápida disponibilização dos resultados para o clínico, antecipando desta forma o diagnóstico e o início rápido do tratamento em benefício do doente. Por outro lado, quando analisámos a relação custo/beneficio, seria vantajosa a implementação desta técnica uma vez que o laboratório dispõe de capacidade técnica, e o custo de aquisição do kit não excede o valor praticado atualmente correspondendo a uma poupança de 51%.

Intravenous Immunoglobulin for the Treatment of Quetiapin-Induced Bullous Pemphigoid in an HIV-Infected Patient

The authors present the case of a 48-year-old woman with HIV-­associated dementia treated with antiretroviral therapy and psychoactive drugs, to whom bullous pemphigoid(BP) was diagnosed. Given incomplete response to corticotherapy, and azathioprine-­induced bicytopenia,intravenous immunoglobulin(IVIG) was initiated. Despite transient disease control, recurrent flares suggested a persistent triggering factor. Specifically, quetiapin was implicated and discontinued with an immediate clinical response. Inadvertent re-­challenge with olanzapine(a related drug)led to a new eruption, confirming drug-­induced BP (DIBP). A total of six IVIG cycles were completed, without severe side effects to report, namely HIV disease progression. HIV-­related autoimmune bullous diseases are rare. Treatment of severe drug eruptions is primarily based on immunossupressive drugs, raising concerns regarding additional immunossupression. This case suggests IVIG as a valuable option for the treatment of BP in HIV patients. In addition, quetiapin should be added to the list of neuroleptics previously linked to DIBP.

Syndrome In Question

Multiple autoimmune syndrome is a rare condition, described by Humbert and Dupond in 1988. It is defined by the association of at least 3 autoimmune diseases in the same patient. Vitiligo is the most common skin condition in this syndrome. This article presents the case of a 31-year-old male with vitiligo, alopecia areata, Crohn's disease, psoriasis vulgaris and oral lichen planus. The rarity of this case is highlighted by the coexistence of four autoimmune skin diseases in association with Crohn's disease, never described in the literature.

Epilepsy and Physical Exercise

Epilepsy is one of the commonest neurologic diseases and has always been associated with stigma. In the interest of safety, the activities of persons with epilepsy (PWE) are often restricted. In keeping with this, physical exercise has often been discouraged. The precise nature of a person’s seizures (or whether seizures were provoked or unprovoked) may not have been considered. Although there has been a change in attitude over the last few decades, the exact role of exercise in inducing seizures or aggravating epilepsy still remains a matter of discussion among experts in the field. Based mainly on retrospective, but also on prospective, population and animal-based research, the hypothesis that physical exercise is prejudicial has been slowly replaced by the realization that physical exercise might actually be beneficial for PWE. The benefits are related to improvement of physical and mental health parameters and social integration and reduction in markers of stress, epileptiform activity and the number of seizures. Nowadays, the general consensus is that there should be no restrictions to the practice of physical exercise in people with controlled epilepsy, except for scuba diving, skydiving and other sports at heights. Whilst broader restrictions apply for patients with uncontrolled epilepsy, individual risk assessments taking into account the seizure types, frequency, patterns or triggers may allow PWE to enjoy a wide range of physical activities.

Evaluation and treatment of the overactive bladder

The overactive bladder is characterized by symptoms of frequency, urgency, and urge incontinence, substantially affecting the quality of life of millions of people throughout the world. The symptoms are associated with significant social, psychological, occupational, domestic, physical, and sexual problems. Despite the considerable impact of this condition on quality of life, sufferers are often unwilling to discuss their problem with family members or health care professionals. This situation is unfortunate, for much can be done to alleviate the symptoms of this distressing condition. It is therefore of utmost importance that medical education about symptoms of the overactive bladder and other related problems be improved to help health care professionals identify and treat patients who will benefit from therapy. This article reviews current thinking regarding definition, epidemiology, quality of life effects, evaluation, and management of the overactive bladder.

Prevalencia das Doencas Cardiacas Ilustrada em 60 Anos dos Arquivos Brasileiros de Cardiologia

Considerando a relevância histórica e acadêmica dos Arquivos Brasileiros de Cardiologia, posto que sua indexa1;ão no MEDLINE iniciou-se em 1950, assumiu-se como hipótese que a análise das publica1;ões de 60 anos poderia refletir as tendências evolutivas das doen1;as cardíacas no Brasil. Os dados do trabalho foram coletados com um programa desenvolvido para a finalidade, tornando possível a extra1;ão automática das informa1;ões do banco de dados MEDLINE. As informa1;ões do trabalho foram coletadas pesquisando-se "Arquivos Brasileiros de Cardiologia AND parâmetro selecionado em inglês". Foram arbitrados quatro grupos observacionais: (1) principais grupos de doen1;as do cora1;ão (doen1;a arterial coronariana, valvulopatia cardíaca, cardiopatias congênitas e cardiomiopatias); (2) doen1;as relevantes na prática clínica (arritmias cardíacas, Cor Pulmonale, infarto do miocárdio e insuficiência cardíaca congestiva); (3) fatores de risco cardiovascular (hipertensão arterial, diabete, dislipidemia e aterosclerose), e; (4) grupo arbitrado em fun1;ão da evolu1;ão crescente das publica1;ões sobre insuficiência cardíaca congestiva constadas nos grupos anteriores (insuficiência cardíaca congestiva, infarto do miocárdio, cardiopatia reumática e cardiopatia chagásica). Foram descritas todas as publica1;ões dentro dos grupos estabelecidos, ressaltando-se o crescente aumento da insuficiência cardíaca e do diabete como fatores de risco. Foi possível um levantamento relativamente fácil, com auxílio do programa de computa1;ão desenvolvido para a pesquisa bibliográfica de seis décadas. Ressaltando-se as limita1;ões do estudo, sugere-se a existência de um elo epidemiológico entre as doen1;as cardiológicas prevalentes no Brasil e as publica1;ões dos Arquivos Brasileiros de Cardiologia.

Association between LDL-C, Non HDL-C, and Apolipoprotein B Levels with Coronary Plaque Regression

Background:Previous reports have inferred a linear relationship between LDL-C and changes in coronary plaque volume (CPV) measured by intravascular ultrasound. However, these publications included a small number of studies and did not explore other lipid markers.Objective:To assess the association between changes in lipid markers and regression of CPV using published data.Methods:We collected data from the control, placebo and intervention arms in studies that compared the effect of lipidlowering treatments on CPV, and from the placebo and control arms in studies that tested drugs that did not affect lipids. Baseline and final measurements of plaque volume, expressed in mm3, were extracted and the percentage changes after the interventions were calculated. Performing three linear regression analyses, we assessed the relationship between percentage and absolute changes in lipid markers and percentage variations in CPV.Results:Twenty-seven studies were selected. Correlations between percentage changes in LDL-C, non-HDL-C, and apolipoprotein B (ApoB) and percentage changes in CPV were moderate (r = 0.48, r = 0.47, and r = 0.44, respectively). Correlations between absolute differences in LDL-C, non‑HDL-C, and ApoB with percentage differences in CPV were stronger (r = 0.57, r = 0.52, and r = 0.79). The linear regression model showed a statistically significant association between a reduction in lipid markers and regression of plaque volume.Conclusion:A significant association between changes in different atherogenic particles and regression of CPV was observed. The absolute reduction in ApoB showed the strongest correlation with coronary plaque regression.