Integrable semi-discretization of the massive Thirring system in laboratory coordinates

Several integrable semi-discretizations are known in the literature for the massive Thirring system in characteristic coordinates. We present for the first time an integrable semi-discretization of the massive Thirring system in laboratory coordinates. Our approach relies on the relation between the continuous massive Thirring system and the Ablowitz-Ladik lattice. The Backlund transformation for solutions to the Ablowitz-Ladik lattice and the time evolution of the massive Thirring system in laboratory coordinates are combined together in the derivation of the Lax system for the integrable semi-discretization of the massive Thirring system.Comment: 10 pages, 0 figure

Leukocyte ratios are useful early predictors for adverse outcomes of COVID-19 infection

Leukocyte biomarkers, including the neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte-(MLR), platelet-to-lymphocyte (PLR) ratios and systemic immune-inflammation index (SII) have been associated with severity and mortality of patients with COVID-19. The purpose of this study was to evaluate the association of baseline leukocyte biomarkers calculated in the emergency department (ED) with the disease severity and mortality. This was a retrospective cohort study that evaluated 1,535 (mean age 57+18 years) patients with SARS-CoV-2 infection in the ED of a single reference center. Outcomes were severity, defined as intensive care unit (ICU) admission requirement, and in-hospital mortality. All leukocyte biomarkers were calculated in the ED before the hospital admission. Their ability to predict the severity and mortality was measured using receiver operating characteristic (ROC) curves. Severity and mortality were observed in 30.9% and 12.6% of the patients, respectively, and were significantly correlated with NLR, MLR, PLR and SII, but only NLR was independently associated with both outcomes on multivariate analysis. Analysis of ROC curves revealed that NLR (0.78 for severity and 0.80 for mortality) and SII (0.77 for severity and 0.75 for mortality) had the best ability to predict mortality, when compared to other ratios. The highest AUC was observed for NLR, employing cut-off points of 5.4 for severity and 5.5 for mortality. Leukocyte biomarkers, particularly NLR, are capable of predicting the severity and mortality of patients with SARS-CoV-2 infection and could be important adjunct tools to identify patients in the ED that are more prone to develop adverse outcomes

Chronic hepatitis C and fibrosis: evidences for possible estrogen benefits

The main injury caused by hepatitis C virus is the hepatic fibrosis, as a result of a chronic inflammatory process in the liver characterized by the deposit of components from the extracellular matrix. The fibrosis development leads to the modification of the hepatic architecture, of the hepatocellular function and to irregularities in the microcirculation. The tissue remodeling process observed in fibrosis has stellate cells, located at the space of Disse, as main acting agents. These cells, in response to a harmful stimulus, undergo phenotypic changes from non-proliferating cells to proliferating cells that express a- smooth-muscle actin (a-SMA), a process called as transdifferentiation. There are evidences that the oxidative stress is involved in the chronic liver disease and serves as bond between the injury and the hepatic fibrosis. A number of studies suggest that the estrogen, at physiological levels, presents an antifibrogenic action probably through an antioxidant effect, decreasing the levels of lipid peroxidation products in the liver and blood, thus inhibiting the myofibroblastic transformation of stellate cells and contributing for gender-associated differences in relation to the fibrosis development. The aim of this paper was to describe data from literature concerning the interaction between chronic hepatitis C and estrogens, pregnancy, use of oral contraceptives, menopause and hormone reposition therapy

Liver International

RESTRITOAbstract: Background/Aim: Pegylated interferon (Peg-IFN) plus ribavirin is the standard therapy for hepatitis C. Peg-IFN has several antiviral mechanisms, but its role in hepatitis C treatment seems to be related to its immunomodulatory effect. Ribavirin, an antiviral agent, potentiates IFN activity when added to it. Both drugs are associated with adverse reactions of different magnitudes. Autoimmune phenomena have been reported with this treatment. In this paper, we describe cases of ALT/GGT flares during Peg-IFN plus ribavirin treatment, which related to the appearance of anti-Golgi antibody and disease progress. Methods: We investigated three patients with hepatitis C and severe ALT/GGT flares during Peg-IFN and ribavirin treatment coinciding with anti-Golgi complex antibody as the only marker of autoimmunity. We then reviewed the medical files and tested anti-Golgi antibody in stored sera from 25 patients treated with conventional IFN and in 14 patients treated with Peg-IFN. Results: The three patients were male, over 45 years of age; all were relapsers and non-responders. Anti-Golgi antibody was positive during treatment coinciding with ALT/GGT flares but with hepatitis C virus (HCV)-RNA negativity, disappearing after stopping treatment, with normalization of ALT/AST levels. One patient had progression of fibrosis from F2 to F3 despite negativity of HCV-RNA. In the last group, only two patients treated with Peg-IFN experienced ALT/GGT flares but without anti-Golgi antibody Conclusions: The presence of anti-Golgi complex antibody could be a marker of a temporary autoimmune phenomenon and progressive disease. Infection with hepatitis C virus (HCV) is an important public health problem worldwide (1). About 55–86% of HCV patients develop chronic infection (2–4). Chronic HCV is usually characterized by a lack of symptoms or only fatigue or abdominal pain. Extra hepatic manifestations are well known and primarily associated with autoimmune or lymphoproliferative states such as arthritis, autoimmune thyroiditis, diabetes mellitus, idiopathic thrombocytopenic purpura, myasthenia gravis, Sjogren syndrome, aplastic anemia, essential mixed (type II) cryoglobulinemia, monoclonal gammopathy and non-Hodking lymphoma. Dermatological manifestations include erythema multiforme, erythema nodosun, Lichen Planus, Porphyria cutanea tarda, psoriasis, pruritus and vasculitis. Idiopathic pulmonary fibrosis and membranoproliferative glomerulonephritis have also been reported (5). Patients with chronic HCV infection do have a higher prevalence rate of autoantibodies in the serum (6). The determination of the antinuclear antibody has thus been recommended before starting HCV therapy (7). Since 1999, interferon (IFN) plus ribavirin is considered as the standard of care for hepatitis C (8). IFN has several antiviral mechanisms, but its role in hepatitis C treatment seems to be related to its immunomodulatory effect (9). Despite its broad spectrum of antiviral activity, ribavirin has a negligible direct antiviral action against HCV replication when used in monotherapy. In contrast, it potentiates IFN activity when added to it, suggesting an additional immunomodulatory effect (10). Both drugs are related to adverse reactions of different magnitudes. Among these side-effects, anemia, neutropenia, thrombopenia, depression and fatigue are the most common, but less frequent adverse reactions related to autoimmune phenomena have been frequently reported. Therapy with IFN-α does also induce autoantibodies in more than half of the patients treated for chronic hepatitis C. Common antibodies are antithyroid, antinuclear antibodies and antibodies against insulin. In the majority of these patients, no evidence of autoimmune disease will develop. However, in susceptible patients, autoimmune features may occur (11, 12). Another unusual side-effect is autoimmune hepatitis, which can prompt immediate discontinuation of the treatment (13). Antithyroid antibodies and autoimmune thyroiditis seem to be the most common side-effects attributable to the immunomodulatory role of IFN. Autoimmune hemolytic anemia and immune-mediated thrombocytopenia purpura were related to this therapy. Autoimmune arthritis including rheumatoid arthritis can emerge during IFN-α therapy as well as systemic lupus erythematosus-like syndrome. Diabetes mellitus may worsen or develop during this therapy (11–16). More recently, Pegylated interferon (Peg-IFN) replaced the conventional one because of best results in terms of sustained virological response (17, 18). Although these newer agents are significantly more effective than earlier versions of standard IFN, the side-effect profile of IFN-based therapies has remained unchanged despite increased incidence of AES. Thus, influenza-like symptoms (fever, myalgia and rigor) and several gastrointestinal disturbances occur with increased frequency (P<0.05) in those treated with Peg-IFN combination therapy compared with standard IFN and ribavirine (19–21). New side-effects of this therapy are reported continuously with the acknowledgment of the results of the different trials (22). During Peg-IFN plus ribavirin treatment, some ALT and GGT elevations are observed, but its mechanism remains unknown (18). Such liver enzyme elevations do not seem to alter antiviral response and even mild to moderate flares are considered benign as they are not related to liver disease progression. In this paper, we described cases of ALT/GGT flares during Peg-IFN plus ribavirin treatment, which were related to anti-Golgi antibody appearance and progressive liver disease. Interestingly, the Golgi apparatus may serve as the starting site of morphological changes associated with viral infection and replication leading to cell fusion and syncytia formation

Hepatoportal sclerosis related to the use of herbal and nutritional supplements. Causality or coincidence?

Introduction and aim. Non-cirrhotic idiopathic portal hypertension (NCIPH), also known as hepatoportal sclerosis (HPS) is a disease of uncertain etiology. However, many pathophysiological mechanisms has been postulated, including thrombophilia, chronic recurrent infections and exposure to drugs or toxins. In this context, it appears to be of multifactorial etiology or resulting from a portal vascular endothelium aggression. It is important to consider whether the use of dietary supplements and herbs can trigger or contribute to the occurance of HPS. We report a possible association of HPS with the consumption of herbal and / or dietary supplements.Material and methods. We describe two cases of HPS in patients without known etiology causes associated with this disease.Results. Both patients were females who were diagnosed with HPS following the consumption of Herbalife® products and putative anorexigenic agents in the herbal infusions. Image-based analysis and the assessment of the histopathological alterations found in the livers confirmed the diagnosis. The histopatological analysis of liver samples from both patients showed portal tracts enlarged by fibrosis with disappearance or reduction in the diameter of the portal vein branches. In many portal tracts, portal veins branches were replaced by aberrant thin-walled fendiforme vessels. The bile ducts and branches of the hepatic artery show normal aspects.Conclusion. After the exclusion of other etiologic factors and a comprehensive analysis of clinical history, consumption of Herbalife® products and anorexigenic agents was pointed-out as a puttative predisposing factor for the development of the disease

Jornal Brasileiro de Patologia e Medicina Laboratorial

p.293-298Hepatites agudas ou crônicas de causas não definidas constituem um problema na prática de médicos clínicos e gastroenterologistas. Apesar do desenvolvimento de sofisticados testes laboratoriais, uma proporção significativa das hepatites ainda permanece com causa não-determinada. São as chamadas hepatites criptogênicas ou hepatites não A-E. Possíveis etiologias são sugeridas: vírus desconhecido, doenças metabólicas ou hepatite auto-imune de apresentação atípica. Recentemente, nosso grupo demonstrou que, num centro de referência no Brasil, 17% dos casos de hepatites agudas são criptogênicos, com alguns aspectos sugerindo etiologia viral. Nós relatamos quatro casos de hepatite aguda criptogênica, demonstrando a heterogeneidade dessa condição clínica associada à possibilidade de complicações, o que justifica uma criteriosa investigação epidemiológica, clínica e laboratorial, assim como o acompanhamento desses pacientes

Hepatite aguda criptogênica: uma entidade heterogênea com possibilidades de complicações

Hepatites agudas ou crônicas de causas não definidas constituem um problema na prática de médicos clínicos e gastroenterologistas. Apesar do desenvolvimento de sofisticados testes laboratoriais, uma proporção significativa das hepatites ainda permanece com causa não-determinada. São as chamadas hepatites criptogênicas ou hepatites não A-E. Possíveis etiologias são sugeridas: vírus desconhecido, doenças metabólicas ou hepatite auto-imune de apresentação atípica. Recentemente, nosso grupo demonstrou que, num centro de referência no Brasil, 17% dos casos de hepatites agudas são criptogênicos, com alguns aspectos sugerindo etiologia viral. Nós relatamos quatro casos de hepatite aguda criptogênica, demonstrando a heterogeneidade dessa condição clínica associada à possibilidade de complicações, o que justifica uma criteriosa investigação epidemiológica, clínica e laboratorial, assim como o acompanhamento desses pacientes