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1.
Pancreatology ; 22(8): 1112-1119, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36369231

RESUMO

BACKGROUND: /Objectives: Sequence variants in several genes have been identified as being associated with an increased inherited risk to develop chronic pancreatitis (CP). In a genetic survey of a CP patient we identified in the PRSS1gene a new c.380C > G sequence variation, giving rise to a non-synonymous p.S127C mutation. Functional studies were performed to analyze the associated pathophysiology of the variant. METHODS: Following generation of an expression vector for the new PRSS1 variant we compared its expression, secretion and catalytic activity with already known PRSS1 risk variants in HEK 293T cells. The intracellular protein accumulation and induction of endoplasmic reticulum (ER)-stress was analyzed. RESULTS: Prediction tool analysis indicated a probably deleterious effect of the p.S127C variant on protein function which was confirmed by detection of a secretion defect in HEK293T cells leading to intracellular protein accumulation. While protein misfolding was associated with reduced trypsin activity, the increased expression of BIP and presence of spliced XBP1 indicated that the p.S127C variant induces ER stress and activates the UPR signaling pathway. CONCLUSIONS: The disease mechanism of the PRSS1 p.S127C variant involves defective protein secretion and the induction of ER-stress due to accumulation of presumably misfolded trypsinogen within the ER. The new variant should be considered disease-causing with an incomplete penetrance. Our results confirm that in addition to dysregulated trypsin-activity or reduced fluid secretion, ER-stress induction is an important trigger for acinar cell damage and the development of recurrent or chronic pancreatic inflammation.


Assuntos
Pancreatite Crônica , Humanos , Tripsina/genética , Tripsina/metabolismo , Células HEK293 , Pancreatite Crônica/genética , Pancreatite Crônica/metabolismo , Tripsinogênio/genética , Mutação
2.
Ann Surg Open ; 2(4): e102, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37637881

RESUMO

Objective: To evaluate (1) the efficacy of transit bipartition (TB) as revisional bariatric surgery (RBS) after laparoscopic sleeve gastrectomy (LSG); (2) the impact of the length of the common channel (CC) on weight loss. Background: LSG in combination with TB has been shown to be highly efficacious for treating morbid obesity. The role of TB as RBS to address the problem of primary failure or weight recidivism after LSG is less well defined. Methods: Observational study of outcomes in 100 morbidly obese patients who received a TB following LSG. Follow-up examinations (FE) were performed at 1, 3, 6, and 12 months. Variables analyzed included BMI, percent excess weight loss (%EWL), total body weight loss (%TBWL), effect on obesity-related conditions and complications. Results: The mean BMI before LSG was 49.9 ± 8.5 kg/m2. A nadir of 32.7 ± 6.1 kg/m2 was reached 22.1 ± 16.9 months after LSG (%EWL 70.0 ± 14.5). The time interval between LSG and TB was 52.2 ± 26.6 months at which the BMI had increased to 37.6 ± 7.1 kg/m2 and %EWL decreased to 49.4 ± 19.7. Following TB, the BMI decreased continuously to 31.4 ± 5.7 kg/m2 after 12 months with a parallel increase in %EWL to 74.7 ± 20.3 and %TWL reaching 36.3 ± 10.5. Weight loss was significantly higher for CC length of 250 versus 300 cm after 12 months (BMI 29.4 ± 5.3/33 ± 5.3 kg/m2, P = 0.002; %EWL 79.8 ± 26.6/70.4 ± 17; P = 0.009). Improvement of comorbidities was observed in a high proportion of patients. Major early complications occurred in 3% of the patients. Conclusion: TB is an effective second-step procedure to address insufficient weight loss or weight recidivism after LSG. CC length of 250 versus 300 cm had a significant impact. While most improvements of obesity-related comorbidities are likely linked to weight loss, amelioration of GERD is largely mediated by accelerated gastric emptying. Major complications were observed in 3% of patients and managed without fatalities.

3.
Surg Obes Relat Dis ; 16(8): 1060-1066, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32473786

RESUMO

BACKGROUND: Single-anastomosis duodeno-ileal bypass (SADI) and the one-anastomosis gastric bypass (OAGB) are 2 revisional procedures to address the problem of weight recidivism after laparoscopic sleeve gastrectomy (LSG). OBJECTIVES: To evaluate the efficacy and safety of SADI and OAGB as revisional bariatric surgery (RBS) in initially super-obese patients (body mass index [BMI] >50 kg/m2). SETTING: Academic hospital, bariatric center of excellence, Germany. METHODS: Observational study of outcomes in 84 initially super-obese patients who had undergone RBS after LSG (SADI n = 42, OAGB n = 42) between July 2013 and April 2018. Follow-up examinations were performed at 1, 6, 12, 24, and 36 months after RBS. The variables analyzed included time between LSG and RBS, BMI, excess weight loss, total weight loss, operation time, and complications. RESULTS: The time interval between LSG and RBS was 45.5 ± 22.8 and 43.5 ± 24.2 months for SADI and OAGB, respectively. At the time of RBS, the mean BMI was 42.8 ± 7.9 kg/m2 for SADI and 43.4 ± 9.2 kg/m2 for OAGB. The follow-up examinations rates (%) after SADI were 97.6, 92.8, 90.5, 78.6, 57.1, and 100, 97.6, 95.2, 85.7, and 59.5 after OAGB. The BMI at the follow-up examinations were 39.1 ± 7.2, 34.2 ± 6.9, 31.2 ± 5.8, 30.2 ± 5.3, 29.3 ± 5.1 for SADI, and 39.5 ± 8.1, 36.6 ± 7.4, 34.7 ± 7.9, 32.9 ± 6.3, and 31.6 ± 5.9 for OAGB. The mean operating times for SADI and OAGB were 138 ± 40 and 123 ± 39 minutes, respectively. Three patients in the SADI group and 1 patient in the OAGB group developed a major complication within the first 30 postoperative days. CONCLUSION: SADI and OAGB were effective second-step procedures for further weight reduction after LSG in initially super-obese patients after short to medium follow-up. There was a trend toward higher weight loss for SADI though this did not reach statistical significance. Substantial differences concerning surgery time and complications between the 2 procedures were not observed.


Assuntos
Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Gastrectomia/efeitos adversos , Derivação Gástrica/efeitos adversos , Alemanha , Humanos , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
4.
J Transl Med ; 17(1): 94, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890175

RESUMO

BACKGROUND: Chronic hepatitis C virus (HCV)-infection is a slowly debilitating and potentially fatal disease with a high estimated number of undiagnosed cases. Given the major advances in the treatment, detection of unreported infections is a consequential step for eliminating hepatitis C on a population basis. The prevalence of chronic hepatitis C is, however, low in most countries making mass screening neither cost effective nor practicable. METHODS: We used a Kohonen artificial neural network (ANN) to analyze socio-medical data of 1.8 million insurants for predictors of undiagnosed HCV infections. The data had to be anonymized due to ethical requirements. The network was trained with variables obtained from a subgroup of 2544 patients with confirmed hepatitis C-virus (HCV) infections excluding variables directly linked to the diagnosis of HCV. All analyses were performed using the data mining solution "RayQ". Training results were visualized three-dimensionally and the distributions and characteristics of the clusters were explored within the map. RESULTS: All 2544 patients with confirmed chronic HCV diagnoses were localized in a clearly defined cluster within the Kohonen self-organizing map. An additional 2217 patients who had not been diagnosed with hepatitis C co-localized to the same cluster, indicating socio-medical similarities and a potentially elevated risk of infection. Several factors including, age, diagnosis codes and drug prescriptions acted only in conjunction as predictors of an elevated HCV risk. CONCLUSIONS: This ANN approach may allow for a more efficient risk adapted HCV-screening. However, further validation of the prediction model is required.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/epidemiologia , Doenças não Diagnosticadas/epidemiologia , Demandas Administrativas em Assistência à Saúde/estatística & dados numéricos , Adulto , Idoso , Inteligência Artificial , Infecções Assintomáticas/epidemiologia , Estudos de Coortes , Mineração de Dados/métodos , Bases de Dados Factuais , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Redes Neurais de Computação , Prevalência , Fatores de Risco , Fatores Socioeconômicos
5.
JACC Cardiovasc Imaging ; 12(8 Pt 2): 1684-1685, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30553671
6.
Open Forum Infect Dis ; 3(1): ofw011, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26973849

RESUMO

Background. Antibiotic-associated diarrhea (AAD) and Clostridium difficile-associated diarrhea (CDAD) are common complications of antibiotic use. Data on the efficacy of probiotics to prevent AAD and CDAD are unclear. We aimed to evaluate the efficacy of Saccharomyces boulardii to prevent AAD and CDAD in hospitalized adult patients. Methods. We conducted a multicenter, phase III, double-masked, randomized, placebo-controlled trial in hospitalized patients who received systemic antibiotic treatment in 15 hospitals in Germany between July 2010 and October 2012. Participants received Perenterol forte 250 mg capsules or matching placebo twice per day within 24 hours of initiating antibiotic treatment, continued treatment for 7 days after antibiotic discontinuation, and were then observed for 6 weeks. Results. Two thousand four hundred forty-four patients were screened. The trial was stopped early for futility after inclusion of 477 participants. Two hundred forty-six patients aged 60.1 ± 16.5 years and 231 patients aged 56.5 ± 17.8 were randomized to the S boulardii group and the placebo group, respectively, with 21 and 19 AADs in the respective groups (P = .87). The hazard ratio of AAD in the S boulardii group compared with the placebo group was 1.02 (95% confidence interval, .55-1.90; P = .94). Clostridium difficile-associated diarrhea occurred in 0.8% of participants (4 of 477). Nine serious adverse events were recorded in the S boulardii group, and 3 serious adverse events were recorded in the placebo group. None were related to study participation. Conclusions. We found no evidence for an effect of S boulardii in preventing AAD or CDAD in a population of hospitalized patients without particular risk factors apart from systemic antibiotic treatment. ClinicalTrials.gov Identifier. NCT01143272.

7.
Case Rep Gastrointest Med ; 2013: 538534, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23936689

RESUMO

The gallbladder is an uncommon site of metastatic cancer. Although ultrasound can be regarded as a first line investigation for the detection of gallbladder lesions, differentiation between benign and malignant tumors usually requires resection. Real-time contrast enhanced ultrasound (CEUS) is a well-established technique for the classification of liver, pancreatic, and renal diseases (Weskott, 2008). The application of CEUS in the diagnosis of gallbladder tumors has rarely been described. We report the application of contrast enhanced ultrasound for the characterization of a gallbladder lesion in a 63-year-old patient with a history of renal cell and rectal cancer.

8.
Int J Colorectal Dis ; 28(8): 1091-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23516071

RESUMO

BACKGROUND: Endoscopic polypectomy significantly reduces the incidence of colorectal cancer, but recurrence rates are high, especially for adenomas with advanced histology. The present guidelines recommend re-colonoscopy 3 to 5 years later. Due to limited resources, more precise predictions of adenoma recurrence are required. DESIGN: Lesions from 109 patients with colorectal adenomas recruited into a randomized, placebo-controlled chemoprevention trial with mesalazine were included. Formalin-fixed paraffin-embedded tissue sections were stained for ß-catenin, cyclooxygenase-2 (Cox-2), and p53 and scored. Adenoma recurrence rates were recorded after 3 years and associated with clinical and immunohistochemical parameters by contingency table analysis. RESULTS: After 3 years, adenomas recurred in 51.4% of patients. Out of 109 adenomas, 95 met at least one criterion of advanced adenoma (size >1 cm, villous histology, high-grade intraepithelial neoplasia). There was no influence of age, sex, size or villous histology on adenoma reappearance, whilst the number of adenomas at baseline was positively associated with recurrence (p = 0.003). In contrast, ß-catenin nuclear localisation, Cox-2 expression and p53 nuclear expression were significantly associated with adenoma recurrence after 3 years (ß-catenin: p = 0.002; Cox-2: p = 0.001; p53: p = 0.001). Combining these three markers led to a negative predictive value of 88.5% and a sensitivity of 94.6%. (OR = 13.54) CONCLUSIONS: Scoring each single parameter and, more strongly, the combination of all three parameters of the expression of ß-catenin, Cox-2 and p53 in colorectal adenoma tissue may be a useful negative predictor for adenoma recurrence in patients with advanced colorectal adenomas.


Assuntos
Pólipos do Colo/cirurgia , Colonoscopia , Neoplasias Colorretais/metabolismo , Ciclo-Oxigenase 2/metabolismo , Recidiva Local de Neoplasia/patologia , Proteína Supressora de Tumor p53/metabolismo , beta Catenina/metabolismo , Adenoma/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fatores de Risco
9.
Carcinogenesis ; 33(3): 637-43, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22198215

RESUMO

Surveillance colonoscopy is an important strategy for prevention of colorectal cancer. 5-aminosalicylate (ASA) (mesalazine) is discussed as a chemopreventive agent as it reduces the cancer risk in ulcerative colitis patients. The current study analyses the effect of 5-ASA on Wnt/ß-catenin signaling in vitro and in vivo in colon epithelial cells. The effect of 5-ASA was determined using a ß-catenin/T-cell factor (TCF)-reporter assay and by western blotting in cultured colon cancer cells. Formalin fixed paraffin embedded material from 227 polyps removed from a subgroup of 56 patients, who participated in a randomized placebo-controlled 3-year prevention trial with 5-ASA was evaluated according to histomorphological characteristics and expression of ß-catenin and target genes Cox2, cyclin D1 and E-cadherin as well as ornithine decarboxylase (ODC). Patients were grouped into a low-risk and a high-risk group according to the number of adenomas at initial colonoscopy. ß-catenin/TCF signaling activity was significantly reduced by 5-ASA treatment possibly through a reduction in ß-catenin levels. Moreover, 5-ASA significantly reduced ß-catenin levels and nuclear localization in patients' adenomas. In addition, 5-ASA also significantly changed expression of the downstream targets Cox2, cyclin D1 and E-cadherin, correlating with ß-catenin status. Moreover, 5-ASA significantly reduced levels of ODC in vivo. Expression of p53 was unaltered by the 5-ASA treatment. Our study shows a significant in vitro and long-term in vivo effect of 5-ASA on ß-catenin signaling as a key signaling pathway in the development of colorectal adenoma. Therefore, we suggest the use of 5-ASA as a promising drug for prevention of sporadic colorectal carcinoma.


Assuntos
Adenoma/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Mesalamina/farmacologia , beta Catenina/metabolismo , Adenoma/prevenção & controle , Caderinas/biossíntese , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Colite Ulcerativa/tratamento farmacológico , Neoplasias Colorretais/prevenção & controle , Ciclina D1/biossíntese , Ciclo-Oxigenase 2/biossíntese , Progressão da Doença , Células Epiteliais/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Masculino , Mesalamina/uso terapêutico , Ornitina Descarboxilase/biossíntese , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição TCF/genética , Fatores de Transcrição TCF/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/biossíntese
10.
World J Gastroenterol ; 16(37): 4747-50, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20872978

RESUMO

Gastrointestinal bleeding from small-bowel varices is a rare and difficult to treat complication of portal hypertension. We describe the case of a 79-year-old female patient with recurrent severe hemorrhage from small-bowel varices 30 years after a complicated cholecystectomy. When double balloon enteroscopy was unsuccessful to reach the site of bleeding, a rendezvous approach was favored with intraoperative endoscopy. Active bleeding from varices within a biliodigestive anastomosis was found and controlled by endoscopic injection of cyanoacrylate. Intraoperative endoscopy should be considered in the case of life-threatening gastrointestinal hemorrhage that is not accessible by conventional endoscopy.


Assuntos
Colecistectomia/efeitos adversos , Endoscopia/métodos , Hemorragia Gastrointestinal , Idoso , Cianoacrilatos/uso terapêutico , Enteroscopia de Duplo Balão , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/cirurgia , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Humanos , Resultado do Tratamento
11.
Hepatology ; 50(3): 707-16, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19637188

RESUMO

UNLABELLED: The inherent sequence diversity of the hepatitis C virus (HCV) with the existence of multiple genotypes that differ up to 20% at the amino acid level represents one of the major obstacles for immune control. Accordingly, immune control of a heterologous virus challenge, particularly across genotypes, is difficult to achieve; however, the overall role of genotype-specific sequence differences has not yet been defined at the epitope level. The aim of this study was to determine the role of genotype-specific sequence differences for the CD8+ T cell response against HCV. We analyzed a cohort of anti-HCV-positive injection drug users infected with HCV genotype 1 (n = 17) or genotype 3 (n = 22) or undetectable HCV-RNA (n = 14) with overlapping peptides covering consensus sequences of NS3 from both genotypes. Importantly, the majority of HCV-specific CD8 T cells were specific for one genotype only indicating that sequence differences between genotypes are relevant at the epitope level. Interestingly, T cells active against both genotypes were significantly more frequent in HCV-RNA-negative subjects. Of note, we identified five subjects with undetectable viremia and coexistence of two T cell populations-one for each genotype-suggesting immune control of two different genotypes. CONCLUSION: We systematically analyzed the degree of cross-genotype reactivity of HCV-specific T cells and have shown that CD8 responses targeting different HCV genotypes can be primed in the same individual and that such responses potentially characterize a subgroup among injection drug users being protected from chronic HCV infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Hepacivirus/imunologia , Hepatite C Crônica/imunologia , Proteínas não Estruturais Virais/genética , Adulto , Reações Cruzadas , Usuários de Drogas , Epitopos , Feminino , Genótipo , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade
12.
Expert Rev Anti Infect Ther ; 7(5): 537-47, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19485794

RESUMO

Approximately 3% of the worldwide population (i.e., more than 170 million people) are chronically infected with the hepatitis C virus (HCV). An estimated 20% of these patients will develop liver cirrhosis within a mean of 20 years, and 2-5% of cirrhotic patients will die of end-stage liver disease or hepatocellular carcinoma. The currently approved antiviral therapy with pegylated interferon (pegIFN) and ribavirin induces a sustained virological response (SVR) in 40-50% of patients infected with genotype 1, the most prevalent HCV type. In this review, we focus on the development and clinical application of serine protease inhibitors as anti-HCV agents. Although highly active in inducing a significant decline of serum HCV RNA, the rapid development of resistance must be counteracted in combination with other antiviral agents, currently pegIFN-alpha and ribavirin. Two serine protease inhibitors have reached clinical Phase III trials, increasing SVR rates and shortening treatment duration when combined with pegIFN and ribavirin. Trials of interferon-free targeted combination therapies are currently underway.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Inibidores de Serina Proteinase/uso terapêutico , Antivirais/química , Ensaios Clínicos como Assunto , Descoberta de Drogas , Farmacorresistência Viral , Hepacivirus/efeitos dos fármacos , Hepacivirus/enzimologia , Hepatite C Crônica/virologia , Humanos , Interferon Tipo I/uso terapêutico , RNA Viral/sangue , Proteínas Recombinantes , Ribavirina/uso terapêutico , Inibidores de Serina Proteinase/química
13.
Med Klin (Munich) ; 104(5): 356-62, 2009 May 15.
Artigo em Alemão | MEDLINE | ID: mdl-19444416

RESUMO

Chronic hepatitis B (HBV) and C virus (HCV) infection can lead to liver cirrhosis, hepatocellular carcinoma and death. Treatment of these worldwide prevalent infectious diseases is subject to intensive research efforts with development of new antiviral substances and optimization of treatment strategies using molecular markers. The goal of HBV and HCV treatment is control and elimination of viral replication, respectively, thereby preventing hepatitis-associated complications. While interferon alpha is used less frequently to treat hepatitis B today, it is still (in the pegylated or albumin-fused form) an essential component of hepatitis C therapy. The growing number of targeted therapies such as new nucleus(t)ide analogs, HCV protease and RNA polymerase inhibitors and other new compounds has added complexity to the treatment of viral hepatitis. This update summarizes the current standard of care as well as new developments in chronic hepatitis B and C therapy.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Antivirais/efeitos adversos , Ensaios Clínicos como Assunto , Estudos Transversais , Farmacorresistência Viral , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/virologia , Humanos , Replicação Viral/efeitos dos fármacos
14.
Antivir Ther ; 14(1): 23-32, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19320234

RESUMO

BACKGROUND: BILB 1941 is a potent and specific nonnucleoside inhibitor of the hepatitis C virus (HCV) RNA polymerase in vitro. METHODS: In a double-blind sequential group comparison, 96 male HCV genotype 1 patients with minimal to mild liver fibrosis (Ishak or Metavir score 0-2) were randomized (8 to active treatment and 2 to placebo per dose group) and treated with 10-450 mg BILB 1941 every 8 h over 5 days. Viral load (VL) was measured using Roche Cobas TaqMan assays. RESULTS: VL decreased by > or =1 log10 IU/ml in 2/8, 2/8, 1/8, 2/7, 0/8, 2/8 and 4/5 patients on 60, 80, 100, 150, 200, 300 and 450 mg, respectively. No response was seen with placebo. HCV subtype 1b showed better response than 1a, the effect of other covariables including prior interferon treatment was not significant. NS5B population sequencing and phenotyping identified baseline samples with reduced BILB 1941 susceptibility, but did not detect an on-treatment emergence of resistant mutants. Plasma drug levels were linear until 300 mg. No serious adverse events (AEs) were reported. AEs were mainly gastrointestinal-related (most frequent diarrhoea) and frequency increased with dose. On 450 mg, all five active-treated patients discontinued (four for gastrointestinal intolerance and one for increased aspartate aminotransferase and alanine aminotransferase levels) and the trial was discontinued. CONCLUSIONS: BILB 1941 monotherapy demonstrated antiviral activity against HCV genotype 1, but gastrointestinal intolerance precluded testing of higher doses.


Assuntos
Inibidores Enzimáticos , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , RNA Viral/antagonistas & inibidores , RNA Viral/genética , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Administração Oral , Adulto , Diarreia/induzido quimicamente , Relação Dose-Resposta a Droga , Método Duplo-Cego , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacocinética , Genótipo , Cefaleia/induzido quimicamente , Hepacivirus/genética , Hepatite C Crônica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de RNA , Fatores de Tempo , Carga Viral , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/genética
15.
Hepatology ; 49(4): 1257-66, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19177598

RESUMO

UNLABELLED: Hepatic cirrhosis is a life-threatening disease arising from different chronic liver disorders. One major cause for hepatic cirrhosis is chronic hepatitis C. Chronic hepatitis C is characterized by a highly variable clinical course, with at least 20% developing liver cirrhosis within 40 years. Only liver biopsy allows a reliable evaluation of the course of hepatitis C by grading inflammation and staging fibrosis, and thus serum biomarkers for hepatic fibrosis with high sensitivity and specificity are needed. To identify new candidate biomarkers for hepatic fibrosis, we performed a proteomic approach of microdissected cirrhotic septa and liver parenchyma cells. In cirrhotic septa, we detected an increasing expression of cell structure associated proteins, including actin, prolyl 4-hydroxylase, tropomyosin, calponin, transgelin, and human microfibril-associated protein 4 (MFAP-4). Tropomyosin, calponin, and transgelin reflect a contribution of activated stellate cells/myofibroblasts to chronic liver injury. The expression of tropomyosin, transgelin, and MFAP-4, an extracellular matrix associated protein, were further evaluated by immunohistochemistry. Tropomyosin and MFAP-4 demonstrated high serum levels in patients with hepatic cirrhosis of different causes. CONCLUSION: A quantitative analysis of MFAP-4 serum levels in a large number of patients showed MFAP-4 as novel candidate biomarker with high diagnostic accuracy for prediction of nondiseased liver versus cirrhosis [area under receiver operating characteristic curve (AUC) = 0.97, P < 0.0001] as well as stage 0 versus stage 4 fibrosis (AUC = 0.84, P < 0.0001), and stages 0 to 3 versus stage 4 fibrosis (AUC = 0.76, P < 0.0001).


Assuntos
Biomarcadores/metabolismo , Proteínas de Transporte/sangue , Proteínas da Matriz Extracelular/sangue , Glicoproteínas/sangue , Cirrose Hepática/metabolismo , Fígado/metabolismo , Proteômica , Adulto , Idoso , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite C/complicações , Humanos , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Tropomiosina/sangue
16.
J Virol ; 82(7): 3438-51, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18216107

RESUMO

Failure of the adaptive immune response to control infection with the hepatitis C virus (HCV) can result from mutational escape in targeted T-cell epitopes. Recent studies suggest that T-cell immune pressure is an important factor in the evolution of the nonstructural proteins in HCV. The aim of this study was to characterize the forces that contribute to viral evolution in an HLA-A*01-restricted epitope in HCV NS3. This epitope represents a potentially attractive target for vaccination strategies since it is conserved across all genotypes. In our cohort of subjects with chronic HCV infection (genotype 1b or 3a), it is a frequently recognized CD8 epitope in HLA-A*01-positive subjects. Viral sequence data reveal that an escape variant is the dominant residue in both genotypes. The predominant Y1444F substitution seemingly impairs binding to the HLA-A*01 molecule, which may have an important impact on the ability to prime a functional CD8 response upon infection. Interestingly, a case of evolution toward the prototype sequence was observed during chronic infection, possibly because the helicase activity of the protein containing the Y1444F substitution is reduced compared to the prototype sequence. Comparison of HCV sequences from Asia and Europe suggests that the frequency of the HLA-A*01 allele in a population may influence the frequency of the escape variant in circulating strains. These data suggest a complex interaction of multiple forces shaping the evolution of HCV in which immune pressure both within the individual and also at the population level in addition to functional constraints are important contributing factors.


Assuntos
Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Evolução Molecular , Hepacivirus/imunologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia , Trifosfato de Adenosina/metabolismo , Adulto , Idoso , Substituição de Aminoácidos/genética , Ásia , DNA Helicases/metabolismo , Europa (Continente) , Feminino , Antígenos HLA-A/metabolismo , Antígeno HLA-A1 , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Ligação Proteica , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência , Proteínas não Estruturais Virais/metabolismo
17.
Antivir Ther ; 11(3): 371-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16759054

RESUMO

We analysed viral kinetics from a 2-day treatment with BILN 2061, a serine protease inhibitor of hepatitis C virus, in patients chronically infected with genotype 1 hepatitis C virus. The efficiency (E), describing inhibition of viral production, was above 99.45% in all patients with minor or moderate fibrosis receiving doses of 200mg and 500 mg twice daily and larger than in previous studies for interferon-based treatments. However, epsilon was slightly smaller in patients with cirrhosis given 200mg and markedly smaller in patients given 25 mg. Estimates of viral clearance and infected-cell loss support conclusions on these rates and on treatment mechanisms from previous studies on interferon-alpha-based treatments.


Assuntos
Carbamatos/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Compostos Macrocíclicos/uso terapêutico , Quinolinas/uso terapêutico , RNA Viral/sangue , Inibidores de Serina Proteinase/uso terapêutico , Tiazóis/uso terapêutico , Adulto , Antivirais/uso terapêutico , Área Sob a Curva , Carbamatos/administração & dosagem , Carbamatos/farmacocinética , Feminino , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/uso terapêutico , Cinética , Compostos Macrocíclicos/administração & dosagem , Compostos Macrocíclicos/farmacocinética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Quinolinas/administração & dosagem , Quinolinas/farmacocinética , Inibidores de Serina Proteinase/administração & dosagem , Inibidores de Serina Proteinase/farmacocinética , Tiazóis/administração & dosagem , Tiazóis/farmacocinética
18.
J Hepatol ; 44(2): 291-301, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16360972

RESUMO

BACKGROUND/AIMS: Therapeutic options for hepatitis C non-responder patients are limited. METHODS: We initiated an open-label pilot study to investigate the efficacy of CIFN plus ribavirin on viral kinetics, sustained virological response (SVR), and histological response in hepatitis C non-responder patients. Seventy-seven patients were enrolled to receive CIFN given daily in combination with 1000/1200 mg ribavirin. An 8-week induction-dosing regimen of 18 microg CIFN, followed by 9 microg for 40 weeks was compared to 9 microg CIFN for 48 weeks. 90% of patients were infected with HCV-genotype 1. RESULTS: Overall, 82% of the patients demonstrated an early virological response, 65% had an end-of-treatment response, and the SVR was 30%. Interferon/ribavirin non-responders demonstrated a SVR of 22%. Induction-dosing resulted in a greater first-phase HCV-RNA decay that, however, did not translate to better SVRs, presumably due to more dose modifications. High ALT, younger age, and second-phase viral kinetics were associated with SVR. Only sustained responders and relapse patients showed an improved liver histology. CONCLUSIONS: Daily dosing of CIFN plus ribavirin may be a promising concept for selected non-responder patients before considering therapies which are anti-viral but not curative. However, motivation and compliance are requisites and a CIFN induction is not required.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , RNA Viral/genética , Ribavirina/uso terapêutico , Adolescente , Adulto , Idoso , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Genótipo , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento
19.
J Virol ; 79(20): 12979-88, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16189000

RESUMO

Multispecific CD8(+) T-cell responses are thought to be important for the control of acute hepatitis C virus (HCV) infection, but to date little information is actually available on the breadth of responses at early time points. Additionally, the influence of early therapy on these responses and their relationships to outcome are controversial. To investigate this issue, we performed comprehensive analysis of the breadth and frequencies of virus-specific CD8(+) T-cell responses on the single epitope level in eight acutely infected individuals who were all started on early therapy. During the acute phase, responses against up to five peptides were identified. During therapy, CD8(+) T-cell responses decreased rather than increased as virus was controlled, and no new specificities emerged. A sustained virological response following completion of treatment was independent of CD8(+) T-cell responses, as well as CD4(+) T-cell responses. Rapid recrudescence also occurred despite broad CD8(+) T-cell responses. Importantly, in vivo suppression of CD3(+) T cells using OKT3 in one subject did not result in recurrence of viremia. These data suggest that broad CD8(+) T-cell responses alone may be insufficient to contain HCV replication, and also that early therapy is effective independent of such responses.


Assuntos
Antivirais/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Hepacivirus/imunologia , Hepatite C/tratamento farmacológico , Hepatite C/imunologia , Doença Aguda , Linfócitos T CD4-Positivos/imunologia , Quimioterapia Combinada , Epitopos de Linfócito T/imunologia , Hepacivirus/química , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Ativação Linfocitária , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes , Ribavirina/uso terapêutico , Regulação para Cima , Proteínas Virais/imunologia
20.
Hepatology ; 41(4): 832-5, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15732092

RESUMO

BILN-2061, a specific and potent peptidomimetic inhibitor of the HCV NS3 protease, has recently been shown to markedly lower serum hepatitis C virus (HCV)-RNA levels in patients chronically infected with HCV genotype 1 in three 2-day proof of principle studies. The aim of the current study was to assess the antiviral efficacy of BILN-2061 in patients with genotypes 2 and 3 HCV infection. The antiviral efficacy, pharmacokinetics, and tolerability of 500 mg twice-daily BILN-2061 given as monotherapy for 2 days in 10 patients chronically infected with non-genotype 1 HCV (genotype 2: n = 3; genotype 3: n =7) and minimal liver fibrosis (Ishak score 0-2) were assessed in a placebo-controlled (placebo n = 2), double-blind pilot study. HCV-RNA levels decreased by > or =1 log(10) copies/mL in 4 of 8 patients treated with BILN-2061. One patient showed a weak response of <1 log(10) copies/mL. Three of 8 treated patients showed no response. There was no correlation between baseline viral concentration or genotype and response. BILN-2061 exhibited good systemic exposure after oral administration and was well tolerated. In conclusion, the antiviral efficacy of the HCV serine protease inhibitor BILN-2061 is less pronounced and more variable in patients with HCV genotype 2 or 3 infection compared with previous results in patients with HCV genotype 1. A lower affinity of BILN-2061 for the NS3 protease of genotypes 2 and 3 HCV is most likely a major contributor to these findings.


Assuntos
Carbamatos/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Compostos Macrocíclicos/uso terapêutico , Quinolinas/uso terapêutico , Inibidores de Serina Proteinase/uso terapêutico , Tiazóis/uso terapêutico , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Adulto , Carbamatos/administração & dosagem , Carbamatos/efeitos adversos , Carbamatos/farmacocinética , Método Duplo-Cego , Esquema de Medicação , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/metabolismo , Humanos , Cinética , Compostos Macrocíclicos/administração & dosagem , Compostos Macrocíclicos/efeitos adversos , Compostos Macrocíclicos/farmacocinética , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Quinolinas/administração & dosagem , Quinolinas/efeitos adversos , Quinolinas/farmacocinética , Inibidores de Serina Proteinase/administração & dosagem , Inibidores de Serina Proteinase/efeitos adversos , Inibidores de Serina Proteinase/farmacocinética , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Tiazóis/farmacocinética , Carga Viral
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