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INTRODUCTION: This study is to evaluate the safety and pharmacokinetics (PK) of larsucosterol (DUR-928 or 25HC3S) in subjects with alcohol-associated hepatitis (AH), a devastating acute illness without US Food and Drug Administration-approved therapies. METHODS: This phase 2a, multicenter, open-label, dose escalation study evaluated the safety, PK, and efficacy signals of larsucosterol in 19 clinically diagnosed subjects with AH. Based on the model for end-stage liver disease (MELD) score, 7 subjects were considered to have moderate AH and 12 to have severe AH. All subjects received 1 or 2 intravenous infusions (72 hours apart) of larsucosterol at a dose of 30, 90, or 150 mg and were followed up for 28 days. Efficacy signals from a subgroup of subjects with severe AH were compared with those from 2 matched arms of those with severe AH treated with standard of care (SOC), including corticosteroids, from a contemporaneous study. RESULTS: All 19 larsucosterol-treated subjects survived the 28-day study. Fourteen (74%) of all subjects including 8 (67%) of the subjects with severe AH were discharged ≤72 hours after receiving a single infusion. There were no drug-related serious adverse events nor early terminations due to the treatment. PK profiles were not affected by disease severity. Biochemical parameters improved in most subjects. Serum bilirubin levels declined notably from baseline to day 7 and day 28, and MELD scores were reduced at day 28. The efficacy signals compared favorably with those from 2 matched groups treated with SOC. Lille scores at day 7 were <0.45 in 16 of the 18 (89%) subjects with day 7 samples. Lille scores from 8 subjects with severe AH who received 30 or 90 mg larsucosterol (doses used in phase 2b trial) were statistically significantly lower ( P < 0.01) than those from subjects with severe AH treated with SOC from the contemporaneous study. DISCUSSION: Larsucosterol was well tolerated at all 3 doses in subjects with AH without safety concerns. Data from this pilot study showed promising efficacy signals in subjects with AH. Larsucosterol is being evaluated in a phase 2b multicenter, randomized, double-blinded, placebo-controlled (AHFIRM) trial.
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Doença Hepática Terminal , Hepatite Alcoólica , Humanos , Projetos Piloto , Índice de Gravidade de Doença , Hepatite Alcoólica/tratamento farmacológico , Hepatite Alcoólica/diagnósticoRESUMO
BACKGROUND & AIMS: Twenty-eight-day mortality ranges from 30-90% in patients with acute-on-chronic liver failure grades 2/3 (severe ACLF). Though liver transplantation (LT) has demonstrated a survival benefit, the scarcity of donor organs and uncertainty regarding post-LT mortality among patients with severe ACLF may cause hesitancy. We developed and externally validated a model to predict 1-year post-LT mortality in severe ACLF, called the Sundaram ACLF-LT-Mortality (SALT-M) score, and estimated the median length of stay (LoS) after LT (ACLF-LT-LoS). METHODS: In 15 LT centers in the US, we retrospectively identified a cohort of patients with severe ACLF transplanted between 2014-2019, followed up to Jan'2022. Candidate predictors included demographics, clinical and laboratory values, and organ failures. We selected predictors in the final model using clinical criteria and externally validated them in two French cohorts. We provided measures of overall performance, discrimination, and calibration. We used multivariable median regression to estimate LoS after adjusting for clinically relevant factors. RESULTS: We included 735 patients, of whom 521 (70.8%) had severe ACLF (120 ACLF-3, external cohort). The median age was 55 years, and 104 with severe ACLF (19.9%) died within 1-year post-LT. Our final model included age >50 years, use of 1/≥2 inotropes, presence of respiratory failure, diabetes mellitus, and BMI (continuous). The c-statistic was 0.72 (derivation) and 0.80 (validation), indicating adequate discrimination and calibration based on the observed/expected probability plots. Age, respiratory failure, BMI, and presence of infection independently predicted median LoS. CONCLUSIONS: The SALT-M score predicts mortality within 1-year after LT in patients with ACLF. The ACLF-LT-LoS score predicted median post-LT stay. Future studies using these scores could assist in determining transplant benefits. IMPACT AND IMPLICATIONS: Liver transplantation (LT) may be the only life-saving procedure available to patients with acute-on-chronic liver failure (ACLF), but clinically instability can augment the perceived risk of post-transplant mortality at 1 year. We developed a parsimonious score with clinically and readily available parameters to objectively assess 1-year post-LT survival and predict median length of stay after LT. We developed and externally validated a clinical model called the Sundaram ACLF-LT-Mortality score in 521 US patients with ACLF with 2 or ≥3 organ failure(s) and 120 French patients with ACLF grade 3. The c-statistic was 0.72 in the development cohort and 0.80 in the validation cohort. We also provided an estimation of the median length of stay after LT in these patients. Our models can be used in discussions on the risks/benefits of LT in patients listed with severe ACLF. Nevertheless, the score is far from perfect and other factors, such as patient's preference and center-specific factors, need to be considered when using these tools.
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Insuficiência Hepática Crônica Agudizada , Transplante de Fígado , Humanos , Pessoa de Meia-Idade , Cirrose Hepática/complicações , Insuficiência Hepática Crônica Agudizada/etiologia , Estudos Retrospectivos , Transplante de Fígado/efeitos adversos , Medição de Risco , PrognósticoRESUMO
BACKGROUND & AIMS: Although liver transplantation (LT) has been demonstrated to provide survival benefit for patients with acute-on-chronic liver failure (ACLF), data are lacking regarding resource utilization for this population after LT. METHODS: We retrospectively reviewed data from 10 centers in North America of patients transplanted between 2018 and 2019. ACLF was identified by using the European Association for the Study of the Liver-Chronic Liver Failure criteria. RESULTS: We studied 318 patients of whom 106 patients (33.3%) had no ACLF, 61 (19.1%) had ACLF-1, 74 (23.2%) had ACLF-2, and 77 (24.2%) had ACLF-3 at transplantation. Healthcare resource utilization after LT was greater among recipients with ACLF compared with patients without ACLF regarding median post-LT length of hospital stay (LOS) (P < .001), length of post-LT dialysis (P < .001), discharge to a rehabilitation center (P < .001), and 30-day readmission rates (P = .042). Multivariable negative binomial regression analysis demonstrated a significantly longer LOS for patients with ACLF-1 (1.9 days; 95% confidence interval [CI], 0.82-7.51), ACLF-2 (6.7 days; 95% CI, 2.5-24.3), and ACLF-3 (19.3 days; 95% CI, 1.2-39.7), compared with recipients without ACLF. Presence of ACLF-3 at LT was also associated with longer length of dialysis after LT (9.7 days; 95% CI, 4.6-48.8) relative to lower grades. Multivariable logistic regression analysis revealed greater likelihood of discharge to a rehabilitation center among recipients with ACLF-1 (odds ratio [OR], 1.79; 95% CI, 1.09-4.54), ACLF-2 (OR, 2.23; 95% CI, 1.12-5.01), and ACLF-3 (OR, 2.23; 95% CI, 1.40-5.73). Development of bacterial infection after LT also predicted LOS (20.9 days; 95% CI, 6.1-38.5) and 30-day readmissions (OR, 1.39; 95% CI, 1.17-2.25). CONCLUSIONS: Patients with ACLF at LT, particularly ACLF-3, have greater post-transplant healthcare resource utilization.
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Insuficiência Hepática Crônica Agudizada , Transplante de Fígado , Humanos , Insuficiência Hepática Crônica Agudizada/complicações , Cirrose Hepática/complicações , Estudos Retrospectivos , Aceitação pelo Paciente de Cuidados de Saúde , PrognósticoRESUMO
Although liver transplantation (LT) yields survival benefit for patients with acute-on-chronic liver failure grade 3 (ACLF-3), knowledge gaps remain regarding risk factors for post-LT mortality. We retrospectively reviewed data from 10 centers in the United States and Canada for patients transplanted between 2018 and 2019 and who required care in the intensive care unit prior to LT. ACLF was identified using the European Association for the Study of the Liver-Chronic Liver Failure (EASL-CLIF) criteria. A total of 318 patients were studied, of whom 106 (33.3%) had no ACLF, 61 (19.1%) had ACLF-1, 74 (23.2%) had ACLF-2, and 77 (24.2%) had ACLF-3 at transplantation. Survival probability 1 year after LT was significantly higher in patients without ACLF (94.3%) compared with patients with ACLF (87.3%; P = 0.02), but similar between ACLF-1 (88.5%), ACLF-2 (87.8%), and ACLF-3 (85.7%; P = 0.26). Recipients with ACLF-3 and circulatory failure (n = 29) had similar 1-year post-LT survival (82.3%) compared with patients with ACLF-3 without circulatory failure (89.6%; P = 0.32), including those requiring multiple vasopressors. For patients transplanted with ACLF-3 including respiratory failure (n = 20), there was a trend toward significantly lower post-LT survival (P = 0.07) among those with respiratory failure (74.1%) compared with those without (91.0%). The presence of portal vein thrombosis (PVT) at LT for patients with ACLF-3 (n = 15), however, yielded significantly lower survival (91.9% versus 57.1%; P < 0.001). Multivariable logistic regression analysis revealed that PVT was significantly associated with post-LT mortality within 1 year (odds ratio, 7.3; 95% confidence interval, 1.9-28.3). No correlation was found between survival after LT and the location or extent of PVT, presence of transjugular intrahepatic portosystemic shunt, or anticoagulation. LT in patients with ACLF-3 requiring vasopressors yields excellent 1-year survival. LT should be approached cautiously among candidates with ACLF-3 and PVT.
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Insuficiência Hepática Crônica Agudizada , Transplante de Fígado , Insuficiência Respiratória , Insuficiência Hepática Crônica Agudizada/complicações , Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/cirurgia , Humanos , Cirrose Hepática/complicações , Transplante de Fígado/efeitos adversos , América do Norte , Prognóstico , Insuficiência Respiratória/complicações , Estudos Retrospectivos , Fatores de RiscoRESUMO
Recent data have demonstrated >80% 1-year survival probability after liver transplantation (LT) for patients with severe acute-on-chronic liver failure (ACLF). However, longterm outcomes and complications are still unknown for this population. Our aim was to compare longterm patient and graft survival among patients transplanted across all grades of ACLF. We analyzed the United Network for Organ Sharing database for the years 2004-2017. Patients with ACLF were identified using the European Association for the Study of the Liver-Chronic Liver Failure criteria. Kaplan-Meier and Cox regression methods were used to determine patient and graft survival and associated predictors of mortality in adjusted models. A total of 56,801 patients underwent transplantation of which 31,024 (54.6%) had no ACLF, 8757 (15.4%) had ACLF grade 1, 9039 (15.9%) had ACLF grade 2, and 7891 (14.1%) had ACLF grade 3. The 5-year patient survival after LT was lower in the ACLF grade 3 patients compared with the other groups (67.7%; P < 0.001), although after year 1, the percentage decrease in survival was similar among all groups. Infection was the primary cause of death among all patient groups in the first year. Infection was the primary cause of death among all patient groups in the first year. After the first year, infection was the main cause of death in patients transplanted with ACLF grade 1 (32.1%), ACLF grade 2 (33.9%), and ACLF grade 3 (37.6%), whereas malignancy was the predominant cause of death in those transplanted with no ACLF (28.5%). In conclusion, patients transplanted with ACLF grade 3 had lower 5-year survival as compared with patients with ACLF grades 0-2, but mortality rates were not significantly different after the first year following LT. Graft survival was excellent across all ACLF groups.
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Insuficiência Hepática Crônica Agudizada , Transplante de Fígado , Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/cirurgia , Bases de Dados Factuais , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/efeitos adversos , Prognóstico , Estudos RetrospectivosRESUMO
INTRODUCTION: Pre-transplant locoregional therapy for hepatocellular carcinoma (HCC) during bridge-to-transplant impacts recurrence and survival rates following liver transplantation. Optimizing the effectiveness of transarterial chemoembolization (TACE) in this population is imperative, and microvalve infusion catheters offer a means of such improvement. METHODS: All treatment-naive patients with solitary HCC tumors < 6.5 cm who underwent drug-eluting microspheres (DEM) TACE between 04/2015 and 08/2017 were retrospectively reviewed. Eighty-eight included patients underwent DEM-TACE with either standard end-hole catheters (EH) or microvalve infusion catheters (MVI). The EH (n = 70) and MVI (n = 18) cohorts had similar baseline tumor size, laboratory values, and tumor etiologies. RESULTS: Initial objective response rates were significantly higher in MVI vs. EH (100% vs. 76.5%, p = 0.019). There was no difference in adverse events between groups (p = 0.265). MVI patients exhibited lower AST (p = 0.003) and ALT (p = 0.044) at 6 months. Blinded pathological analysis of explanted livers showed greater concentrations of microspheres within the tumor relative to the surrounding tissue in MVI explants (88.7 ± 10.6%) versus the EH explants (55.3 ± 32.7%) (p = 0.002). There was significantly higher percentage tumor necrosis in the MVI group (89.0 ± 2.2%) compared with the EH group (56.1 ± 44.5%) (p = 0.006). CONCLUSION: In this retrospective study of a single-center cohort, DEM-TACE procedures with MVI were associated with improved tumor response, increased deposition of microspheres within tumor tissue, and higher percentage tumor necrosis at explant relative to those performed using EH catheters.
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Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica/instrumentação , Neoplasias Hepáticas/tratamento farmacológico , Microesferas , Dispositivos de Acesso Vascular , Adulto , Idoso , Antineoplásicos/farmacocinética , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Desenho de Equipamento , Feminino , Humanos , Neoplasias Hepáticas/patologia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Pré-Medicação , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Severe alcoholic hepatitis (sAH) is associated with a poor prognosis. There is no proven effective treatment for sAH, which is why early transplantation has been increasingly discussed. Hepatoblastoma-derived C3A cells express anti-inflammatory proteins and growth factors and were tested in an extracorporeal cellular therapy (ELAD) study to establish their effect on survival for subjects with sAH. Adults with sAH, bilirubin ≥8 mg/dL, Maddrey's discriminant function ≥ 32, and Model for End-Stage Liver Disease (MELD) score ≤ 35 were randomized to receive standard of care (SOC) only or 3-5 days of continuous ELAD treatment plus SOC. After a minimum follow-up of 91 days, overall survival (OS) was assessed by using a Kaplan-Meier survival analysis. A total of 203 subjects were enrolled (96 ELAD and 107 SOC) at 40 sites worldwide. Comparison of baseline characteristics showed no significant differences between groups and within subgroups. There was no significant difference in serious adverse events between the 2 groups. In an analysis of the intent-to-treat population, there was no difference in OS (51.0% versus 49.5%). The study failed its primary and secondary end point in a population with sAH and with a MELD ranging from 18 to 35 and no upper age limit. In the prespecified analysis of subjects with MELD < 28 (n = 120), ELAD was associated with a trend toward higher OS at 91 days (68.6% versus 53.6%; P = .08). Regression analysis identified high creatinine and international normalized ratio, but not bilirubin, as the MELD components predicting negative outcomes with ELAD. A new trial investigating a potential benefit of ELAD in younger subjects with sufficient renal function and less severe coagulopathy has been initiated. Liver Transplantation 24 380-393 2018 AASLD.
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Circulação Extracorpórea/métodos , Hepatite Alcoólica/terapia , Hepatoblastoma/metabolismo , Neoplasias Hepáticas/metabolismo , Adulto , Austrália , Linhagem Celular Tumoral , Circulação Extracorpórea/efeitos adversos , Circulação Extracorpórea/mortalidade , Feminino , Hepatite Alcoólica/sangue , Hepatite Alcoólica/diagnóstico , Hepatite Alcoólica/mortalidade , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Reino Unido , Estados UnidosRESUMO
OBJECTIVES: To measure prescribed time to therapy (TtT) and sustained virologic response (SVR). Secondary objectives were to assess insurance appeals and copay assistance amount facilitated by a local specialty pharmacy (LSP). METHODS: This descriptive, retrospective study used a joint clinical and pharmacy database of patients who were prescribed direct-acting antivirals (DAAs) at a single-center liver specialty clinic and received LSP services from December 2013 to December 2015. RESULTS: Among 388 patients prescribed DAAs, 364 (94%) patients, who were 18 years of age or older, initiated DAA therapy, and received LSP services, were included in the study. Of these, 211 (58.0%) had cirrhosis, 159 (43.7%) had previous treatment, and 57 (15.7%) had previous liver transplants. Most patients had commercial insurance (n = 249; 68.4%), and 295 (81.0%) required prior authorization. Insurance initially denied coverage to 70 patients (19.2%), for who the LSP drafted appeals for 60 (85.7%). Copay information was available for 154 LSP patients. Although 66 had initial copays of more than $20 per month, the LSP was able to assist most (98.1%; n = 151) with copay reductions to $20 or less. Full financial assistance was received for 20 patients without insurance or any DAA coverage. Among 171 patients with SVR and prescribed TtT information, mean TtT was 12 days (median 4 days), and most received medications within 10 days (n = 122; 71.3%). The overall intention-to-treat SVR rate was 86.8%; the per-protocol (PP) SVR rate was 93.8%. CONCLUSION: Collaboration between providers and an LSP minimized delay in therapy, lowered rates of DAA denial, facilitated patient financial assistance, and helped to optimize clinical outcomes. The PP-SVR rate for this study was similar to rates reported in the literature and higher than expected, considering the inclusion of earlier-generation DAAs and many patients with advanced liver disease.
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Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Assistência Farmacêutica/estatística & dados numéricos , Farmácia/estatística & dados numéricos , Comportamento Cooperativo , Feminino , Hepacivirus/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resposta Viral SustentadaRESUMO
Although chronic hepatitis C is still the leading indication for liver transplantation (LT) in the United States and Europe, acute liver failure caused by hepatitis C is distinctly uncommon and transplantation for fulminant hepatitis C virus (HCV) has not been documented in the United States. We present a case report of fulminant hepatic failure caused by genotype 2a/c HCV not only treated with LT but also complicated by severe, rapid recurrence of HCV within 6 days of transplantation. The risk factor for the initial infection was likely sexual, and there were no explanations for acute hepatitis post-transplant other than recurrent hepatitis C. Treatment with all-oral direct antiviral agents was swiftly initiated during the index hospitalization, leading to resolution of the acute hepatitis and resulting in sustained virologic response. It can only be speculated whether this was an infection with the JFH-1 strain or another similarly virulent genotype 2a/c HCV infection.
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Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C/terapia , Falência Hepática Aguda/cirurgia , Transplante de Fígado/efeitos adversos , Doença Aguda , Administração Oral , Carbamatos , Quimioterapia Combinada , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C/sangue , Hepatite C/complicações , Hepatite C/genética , Humanos , Imidazóis/uso terapêutico , Falência Hepática Aguda/sangue , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Pirrolidinas , Recidiva , Ribavirina/uso terapêutico , Fatores de Risco , Sofosbuvir/uso terapêutico , Valina/análogos & derivadosRESUMO
Gastrointestinal neuroendocrine tumors (NET) are rare but the age-adjusted incidence in the United States has increased, possibly due to improved radiographic and endoscopic detection. In advanced NET, hepatic metastases are common. Orthotopic liver transplant (OLT) is currently considered an acceptable therapy for selected patients with limited hepatic disease or liver metastases where complete resection is thought to have curative intent. The development of NET of donor origin is very uncommon after organ transplant, and it is unclear if the same treatment strategies applied to hepatic NET would also be efficacious after OLT. Here, we describe a unique case of an OLT recipient with a donor-derived NET that was treated with redo OLT as the primary therapy. The donor-derived NET recurred in the recipient's second liver allograft suggesting an extrahepatic reservoir. This case describes the natural history of such a rare event. Here, we highlight the treatment options for hepatic NET and challenge the role of OLT for a donor-derived hepatic NET.
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Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Feminino , Humanos , MasculinoRESUMO
PURPOSE: To identify prognostic factors for survival in patients with hepatocellular carcinoma (HCC) treated with transarterial chemoembolization with doxorubicin-eluting beads (DEBs). MATERIALS AND METHODS: In a retrospective, single-center analysis, tumor- and patient-related factors were recorded for univariate and multivariate analyses via Kaplan-Meier and Cox regression. Infiltrative HCC phenotype and portal vein invasion (PVI) were correlated, and patients with either or both were classified as having radiographically advanced (RAdv) HCC. The primary endpoint was overall survival, which was calculated from the time of first DEB chemoembolization procedure. RESULTS: A total of 168 patients underwent 248 procedures, of which 215 (86.7%) were outpatient procedures. Mean length of stay was 0.33 days, and 25 patients (10.1%) were readmitted within 30 days. A total of 33 patients underwent liver transplantation and were excluded from survival analyses. A total of 130 had cirrhosis; 62, 50, and 18 had Child class A, B, and C disease, respectively. Forty-one patients had infiltrative HCC phenotype, 28 of whom also had PVI. Multivariate analysis of survival in all patients showed α-fetoprotein (AFP), performance status (PS), RAdv HCC, Child classification, albumin level, and ascites to predict survival. In patients without RAdv HCC, AFP, PS, Child classification, albumin level, and International Normalized Ratio were independent predictors. Increased bilirubin level was not an independent risk factor for death. CONCLUSIONS: Independent prognostic factors in patients with HCC undergoing DEB chemoembolization have been identified. Increased bilirubin level was not an independent risk factor. These data can be used in HCC patient selection and counseling for DEB chemoembolization.
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Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/mortalidade , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/terapia , Modelos de Riscos Proporcionais , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/administração & dosagem , Stents Farmacológicos/estatística & dados numéricos , Feminino , Georgia/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Medição de Risco , Análise de Sobrevida , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Marasmus is a severe form of protein-calorie malnutrition characterized by the depletion of fat stores, muscle wasting, and the lack of edema. In developed countries, marasmus is often the result of anorexia nervosa. Abnormal transaminases with liver synthetic dysfunction have rarely been reported with anorexia nervosa. To our knowledge, we report the first detailed case of acute liver injury with severe coagulopathy (INR > 1.5) in a patient with marasmus due to self-induced calorie restriction caused by a somatic delusional disorder. This case highlights the severity of liver injury that may occur with significant weight loss from self-induced calorie restriction and the rapid normalization of this injury with treatment. It is important for clinicians to be aware of patterns of acute liver injury in patients with severe protein-calorie malnutrition, regardless of the underlying cause.
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Although humans and chimpanzees share >99% identity in alignable protein sequences, they differ surprisingly in the incidence and severity of some common diseases. In general, humans infected with various viruses, such as HIV and hepatitis C virus, appear to develop stronger reactions and long-term complications. Humans also appear to suffer more from other diseases associated with over-reactivity of the adaptive immune system, such as asthma, psoriasis, and rheumatoid arthritis. In this study, we show that human T cells are more reactive than chimpanzee T cells to a wide variety of stimuli, including anti-TCR Abs of multiple isotypes, l-phytohemagglutin, Staphylococcus aureus superantigen, a superagonist anti-CD28 Ab, and in MLRs. We also extend this observation to B cells, again showing a human propensity to react more strongly to stimuli. Finally, we show a relative increase in activation markers and cytokine production in human lymphocytes in response to uridine-rich (viral-like) ssRNA. Thus, humans manifest a generalized lymphocyte over-reactivity relative to chimpanzees, a finding that is correlated with decreased levels of inhibitory sialic acid-recognizing Ig-superfamily lectins (Siglecs; particularly Siglec-5) on human T and B cells. Furthermore, Siglec-5 levels are upregulated by activation in chimpanzee but not human lymphocytes, and human T cell reactivity can be downmodulated by forced expression of Siglec-5. Thus, a key difference in the immune reactivity of chimp and human lymphocytes appears to be related to the differential expression of Siglec-5. Taken together, these data may help explain human propensities for diseases associated with excessive activation of the adaptive immune system.
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Imunidade Adaptativa , Linfócitos B/imunologia , Linfócitos B/metabolismo , Ativação Linfocitária/imunologia , Pan troglodytes/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/metabolismo , Síndrome da Imunodeficiência Adquirida/patologia , Imunidade Adaptativa/genética , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Antígenos CD/fisiologia , Antígenos de Diferenciação Mielomonocítica/biossíntese , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/fisiologia , Linfócitos B/virologia , Proliferação de Células , Células Cultivadas , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Inibidores do Crescimento/biossíntese , Inibidores do Crescimento/genética , Inibidores do Crescimento/fisiologia , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Hepatite C/imunologia , Hepatite C/metabolismo , Hepatite C/patologia , Humanos , Lectinas/biossíntese , Lectinas/genética , Lectinas/fisiologia , Receptores de Superfície Celular/fisiologia , Linfócitos T/virologia , Regulação para Cima/genética , Regulação para Cima/imunologiaRESUMO
Nonalcoholic fatty liver disease (NAFLD), first described in 1980, is now recognized as one of the most common causes of elevated liver enzymes and chronic liver disease in Western countries. The incidence of NAFLD in both adults and children is rising, in conjunction with the burgeoning epidemics of obesity and type 2 diabetes mellitus. NAFLD often coexists with other sequelae of the metabolic syndrome: central obesity, type 2 diabetes, hypertension, and hyperlipidemia. NAFLD encompasses a spectrum of pathologic liver diseases ranging from simple hepatic steatosis to a predominant lobular necro-inflammation, with or without centrilobular fibrosis (called nonalcoholic steatohepatitis or NASH). NASH can progress to cirrhosis, decompensated liver disease, and hepatocellular carcinoma. Though the natural history of NASH is still not clearly defined, it has been observed to progress to cirrhosis in 15%-220% of those affected. Insulin resistance is nearly universal in NASH and is thought to play an important role in its pathogenesis leading to dysregulated lipid metabolism. The prevalence of insulin resistance is reported in the general population to be approaching 45%, suggesting that NAFLD and NASH will contin nue to be an important public health concern. To date, NASH has proven to be a difficult disease to treat. Front-line therapy with lifestyle modifications resulting in weight loss through decreased caloric intake and moderate exercise is generally believed to be beneficial in patients with NASH, but is often difficult to maintain long term. Given that insulin resistance plays a dominant role in the pathogenesis, many studies have examined the use of insulin sensitizers: the biguanides (metformin), thiazolidinediones (pioglitazone, troglitazone, and rosiglitazone), glucagon-like peptide-1-receptor agonists, or incretins (exenatide)in NASH. This review will provide an overview of insulin resistance in NAFLD and provide a detailed summary on the clinical data regarding the use of insulin sensitizers in NASH.
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Fígado Gorduroso/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Resistência à Insulina/fisiologia , Fígado Gorduroso/fisiopatologia , Peptídeo 1 Semelhante ao Glucagon/agonistas , Glucose/metabolismo , Humanos , Metformina/uso terapêutico , Prevalência , Tiazolidinedionas/uso terapêutico , Triglicerídeos/metabolismoRESUMO
Hepatitis B virus infection (HBV) is a significant global health problem. Despite the success of universal hepatitis B vaccination in many countries, more than 350 million individuals worldwide are chronically infected and 15- 40% of those will develop cirrhosis and/or hepatocellular carcinoma if left untreated. Available therapies for chronic hepatitis B (CHB) infection are effective at decreasing viremia and improving measured clinical outcomes, however, no single therapy is optimal. As such, alternative drug therapies and the investigation of their role in the management of CHB are warranted. Significant improvements in the understanding of the HBV life cycle, viral genomics, and virus-host interactions continue to lead to the development of novel viral targets and immune modulators. Currently, two major classes of agents are utilized in CHB: the interferons and the nucleos(t)ide analogues. Each agent has individual advantages and drawbacks. The development of specific antiviral therapy has led to the emergence of HBV drug-resistant strains that has limited the long-term therapeutic potential of available agents. This necessitates the development of new agents that target both wild-type and drug-resistant strains. Further understanding of the basic mechanisms and clinical nuances of drug therapy is warranted. As most novel therapies are in the earliest stages of clinical development and testing, in the near future, treatment will continue to be long-term and likely involve the use of combination therapies to prevent viral resistance. In this review, we will highlight the HBV life cycle and genome, focusing in on current and potential novel antiviral drug targets as well as the benefits and clinical challenges with these therapies.
Assuntos
Antivirais/farmacologia , Antivirais/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Antivirais/química , Vacinas contra Hepatite B/uso terapêutico , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/fisiologia , Humanos , Fatores Imunológicos/uso terapêutico , Interferons/farmacologia , Interferons/uso terapêutico , Inibidores da Síntese de Ácido Nucleico , RNA Interferente Pequeno/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/fisiologia , VacinaçãoRESUMO
Leptin has properties of a profibrogenic cytokine. In liver, the activated hepatic stellate cell (HSC) is responsible for a net production of extracellular matrix. A key molecule synthesized is the tissue inhibitor of metalloproteinase I (TIMP-1), which acts to inhibit the activity of matrix metalloproteinases. The purpose of the present study was to determine how leptin, a gp130 cytokine, orchestrates the regulation of TIMP-1 gene activation and expression. Transient transfection of primary HSCs revealed that leptin significantly increased luciferase activity of a 229-bp TIMP-1 promoter construct (TIMP-1-229). An EMSA revealed that leptin enhanced specificity protein 1 (Sp1) binding. Site-directed mutagenesis for Sp1 reduced the enhancing effect of leptin on TIMP-1 transcriptional activation, and this effect was dose dependent on the number of Sp1 sites mutated. Chromatin immunoprecipitation revealed that leptin enhanced binding of Sp1; however, inhibition of signal transducer and activator of transcription (STAT) 3 phosphorylation by AG490 also blocked Sp1 phosphorylation and significantly reduced leptin-associated TIMP-1-229 promoter activity, indicating that one mechanism for leptin-increased transcriptional activity is via phosphorylation of Sp1 and subsequent promoter binding. Finally, we demonstrate that leptin also results in intranuclear pSTAT3 binding to Sp1. We propose a novel mechanism whereby leptin-mediated TIMP-1 transcription employs a Sp1/pSTAT3-dependent mechanism, one of which is a noncanonical association between Sp1 and pSTAT3. These data provide a new molecular mechanism whereby the adipocytokine leptin plays a role in complications of the metabolic syndrome.