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1.
Hepatology ; 48(5): 1549-57, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18846542

RESUMO

UNLABELLED: Primary biliary cirrhosis (PBC) is sometimes diagnosed based on a positive antimitochondrial antibody in the appropriate clinical setting without a liver biopsy. Although a liver biopsy can assess the extent of liver fibrosis and provide prognostic information, serum fibrosis markers avoid biopsy complications and sampling error and provide results as a continuous variable, which may be more precise than categorical histological stages. The current study was undertaken to evaluate serum fibrosis markers as predictors of clinical progression in a large cohort of PBC patients. Serial liver biopsy specimens and serum samples were collected every 2 years in 161 PBC subjects for a median of 7.3 years. Clinical progression was defined as development of one or more of the following events: varices, variceal bleed, ascites, encephalopathy, liver transplantation, or liver-related death. Serum hyaluronic acid, tissue inhibitor of metalloproteinase 1, and procollagen III aminopeptide were measured and entered into the previously validated enhanced liver fibrosis (ELF) algorithm. The ability of ELF, histological fibrosis, bilirubin, Model for End-Stage Liver Disease (MELD), and Mayo Risk Score to differentiate between individuals who would experience a clinical event from those who would not was evaluated at different time points. Event-free survival was significantly lower in those with high baseline ELF. Each 1-point increase in ELF was associated with a threefold increase in future complications. The prognostic performance of all tests was similar when performed close to the time of the first event. However, at earlier times in the disease process (4 and 6 years before the first event), the prognostic performance of ELF was significantly better than MELD or Mayo R score. CONCLUSION: The ELF algorithm is a highly accurate noninvasive measure of PBC disease severity that provides useful long-term prognostic information.


Assuntos
Cirrose Hepática Biliar/terapia , Adulto , Algoritmos , Bilirrubina/sangue , Biópsia , Progressão da Doença , Fibrose , Humanos , Imunossupressores/uso terapêutico , Cirrose Hepática Biliar/tratamento farmacológico , Cirrose Hepática Biliar/imunologia , Cirrose Hepática Biliar/patologia , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Prognóstico , Resultado do Tratamento
2.
Aliment Pharmacol Ther ; 20(9): 943-9, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15521841

RESUMO

BACKGROUND: Ursodeoxycholic acid has been ineffective in the treatment of primary sclerosing cholangitis. Because the pathogenesis of primary sclerosing cholangitis is related to immune destruction of bile duct epithelium, several immune suppressive agents have been evaluated. Mycophenolate mofetil is a potent immunosuppressant that is now widely used in organ transplantation. AIM: In this pilot study to determine if mycophenolate mofetil when combined with ursodeoxycholic acid could prevent evidence of clinical progression and improve the biochemical, histological and/or cholangiographic features of primary sclerosing cholangitis compared with patients treated with ursodeoxycholic acid alone. METHODS: Twenty-five patients with well-defined primary sclerosing cholangitis were randomized to ursodeoxycholic acid (13-15 mg/kg/day) with or without mycophenolate mofetil (1000 mg b.d.). Cholangiography and liver biopsy were performed at study entry and after 2 years of treatment. Symptoms, clinical features of liver disease and biochemical tests were monitored at 3-month intervals. RESULTS: The mean age 44 years, 58% male, 84% Caucasian and 64% had ulcerative colitis. After 2 years, there were no differences in laboratory values, histological stage or cholangiograms between patients treated with ursodeoxycholic acid alone and those treated with mycophenolate mofetil + ursodeoxycholic acid. CONCLUSIONS: Mycophenolate mofetil combined with ursodeoxycholic acid does not appear to provide additional benefit compared with standard doses of ursodeoxycholic acid alone in the treatment of primary sclerosing cholangitis.


Assuntos
Colagogos e Coleréticos/uso terapêutico , Colangite Esclerosante/tratamento farmacológico , Imunossupressores/uso terapêutico , Fígado/patologia , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Ácido Ursodesoxicólico/uso terapêutico , Adulto , Biópsia/métodos , Colangite Esclerosante/patologia , Feminino , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos
3.
Liver Transpl ; 7(4): 363-73, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11303298

RESUMO

Many subjects with cryptogenic cirrhosis have underlying nonalcoholic steatohepatitis (NASH). The natural history of NASH-related cryptogenic cirrhosis after orthotopic liver transplantation (OLT) is not well defined. A primarily retrospective study of patients with the clinical histological phenotype of NASH-related cirrhosis undergoing OLT was performed. Data were compared with 2 sets of age- and weight-matched controls with (1) primary biliary cirrhosis or primary sclerosing cholangitis or (2) alcoholic liver disease. After OLT, all patients were managed by a standard immunosuppressive protocol. Liver biopsies were performed at 6 and 12 months after OLT and at 1- to 2-year intervals thereafter, as well as when liver enzyme levels were elevated enough to warrant diagnostic biopsy. Twenty-seven subjects with cryptogenic cirrhosis and a clinical histological phenotype of NASH and 3 patients with a long-standing diagnosis of NASH before OLT were included. The 30-day perioperative mortality was 1 in 30 patients. During a median follow-up of 3.5 +/- 2.7 years, 2 additional patients died of sepsis. There was a time-dependent increase in the risk for allograft steatosis that approached 100% by 5 years compared with only an approximately 25% incidence of steatosis in the control groups (P <.009, log-rank test). On multivariate analysis, only the cumulative steroid dose correlated with time to development of allograft steatosis. Three patients developed histological progression from hepatic steatosis to steatohepatitis. Of these, 1 patient developed progressive fibrosis. Four patients experienced at least 1 episode of acute cellular rejection; however, no patient developed chronic rejection or graft failure. In conclusion, nonalcoholic fatty liver disease occurs frequently after OLT in patients with the phenotype of NASH-related cirrhosis. Despite the frequent histological recurrence of disease, clinical outcomes are similar to those of other groups of patients undergoing OLT.


Assuntos
Fígado Gorduroso/etiologia , Cirrose Hepática/cirurgia , Transplante de Fígado , Complicações Pós-Operatórias , Adulto , Progressão da Doença , Fígado Gorduroso/patologia , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
5.
Am Surg ; 66(2): 219-22, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10695758

RESUMO

The case of a young woman presenting with fever, abdominal distention, and diarrhea is presented. While hospitalized, she developed peritonitis, and a laparotomy was performed emergently. Intraoperative and pathologic examinations are highly suggestive of Salmonella typhi as an etiology for her symptoms and eventual perforation. Salmonella enteritis can be a difficult diagnosis to make, but in most cases it is a self-limited disease process. In a minority of cases, multidrug antibiotic therapy may be required secondary to an increasing prevalence of resistant strains. Patients who perforate require prompt operation to limit morbidity and mortality. Outcome is significantly improved in those patients by directed resection of the affected segment of bowel and by aggressive perioperative care.


Assuntos
Enterite/microbiologia , Perfuração Intestinal/microbiologia , Doenças do Jejuno/microbiologia , Febre Tifoide/complicações , Adulto , Feminino , Humanos , Salmonella typhi
6.
J Cereb Blood Flow Metab ; 20(1): 82-92, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10616796

RESUMO

Hypoglycemia can cause brain dysfunction, brain injury, and death. The present study seeks to broaden current information regarding mechanisms of hypoglycemic brain injury by investigating a novel etiology. The cat's high resistance to brain injury from hypoglycemia suggested that additional influences such as respiratory depression might play a facilitating role. Three groups of cats were exposed to fasting and insulin-induced hypoglycemia (HG; n = 6), euglycemic respiratory depression (RD; n = 5), and combined hypoglycemic respiratory depression (HG/RD; n = 10). The HG animals were maintained at <1.5 mmol (mean 1 mmol) serum glucose concentration for 2 to 6.6 hours. The respiratory depression was associated with PaO2 and PaCO2 values of approximately 50 mm Hg for 1 hour and of approximately 35 and approximately 75 mm Hg, respectively, for the second hour. Magnetic resonance diffusion-weighted imaging estimated brain energy state before, during, and after hypoglycemia. The hypoglycemic respiratory depression exposures were terminated either to euglycemia (n = 4) or to hyperglycemia (n = 6). Brain injury was assessed after 5 to 7 days of survival. Cats exposed to hypoglycemia alone maintained unchanged diffusion coefficients; that is, they lacked evidence of brain energy failure and all six remained brain-intact. Only 1 of 5 euglycemic RD but 10 of 10 HG/RD cats developed brain damage (HG and RD vs. HG/RD, P < 0.01). This difference in brain injury rates suggests injury potentiation by hypoglycemia and respiratory depression acting together. Three injury patterns emerged, including activation of microglia, selective neuronal necrosis, and laminar cortical necrosis. Widespread activation of microglia suggesting damage to neuronal cell processes affected all damaged brains. Selective neuronal necrosis affecting the cerebral cortex, hippocampus, and basal ganglia was observed in all but one case. Instances of laminar cortical necrosis were limited to cats exposed to hypoglycemic respiratory depression treated with hyperglycemia. Thus, treatment with hyperglycemia compared with euglycemia after hypoglycemic respiratory depression exposures significantly increased the brain injury scores (24 +/- 6 vs. 13 +/- 2 points; P < 0.05). This new experimental hypoglycemia model's contribution lies in recognizing additional factors that critically define the occurrence of hypoglycemic brain injury.


Assuntos
Encefalopatias/etiologia , Encéfalo/patologia , Hiperglicemia/fisiopatologia , Hipoglicemia/complicações , Transtornos Respiratórios/fisiopatologia , Animais , Encefalopatias/diagnóstico , Gatos , Eletroencefalografia , Feminino , Hiperglicemia/complicações , Hiperglicemia/diagnóstico , Hipoglicemia/patologia , Imageamento por Ressonância Magnética , Masculino , Transtornos Respiratórios/complicações , Transtornos Respiratórios/diagnóstico
7.
Am J Gastroenterol ; 94(12): 3576-82, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10606322

RESUMO

OBJECTIVES: Hepatitis C virus (HCV) is common in patients with end stage renal disease (ESRD) awaiting renal transplantation (RT). However, few data are available on the liver histology and viral titer in these patients relative to patients with HCV and normal renal function. The aims of this study were to assess liver histology, quantitative HCV-RNA titer, and alanine aminotransferase (ALT) levels in patients with ESRD awaiting RT, and to identify clinical predictors of histological progression to advanced bridging fibrosis and/or cirrhosis. METHODS: A total of 50 consecutive patients (mean age 42 yr, 62% male) with ESRD and HCV, who were awaiting RT, underwent liver biopsy. Two HCV populations, one with persistently normal ALT and another with elevated ALT, both with normal renal function, served as controls. HCV-RNA titer was assessed by quantitative PCR. RESULTS: Of the patients with ESRD, 94% had normal ALT. Log HCV RNA titer was significantly higher in patients with ESRD (5.8+/-0.3) than in either normal ALT (5.4+/-0.1) or elevated ALT (5.3+/-0.1) controls (p < 0.05). Knodell Histological Activity Index (HAI) in patients with ESRD was similar to that observed in control patients with normal ALT (4.8+/-0.4 vs 4.9+/-0.4) but significantly less (p < 0.05) than that observed in control patients with elevated ALT (8.4+/-0.5). The percentage of patients with bridging fibrosis or cirrhosis was similar in patients with ESRD and controls with persistently normal ALT (22% vs 13%) but significantly less (p < 0.001) than that observed in control patients with elevated ALT (48%). No significant differences in ALT, HCV-RNA titer, duration on hemodialysis, or time from first possible exposure was observed between ESRD patients with advance fibrosis (n = 11) and those with mild disease (n = 39). CONCLUSIONS: Our data suggest that liver biopsy is necessary to exclude significant liver pathology in patients with HCV and ESRD, and to help define those patients in whom interferon treatment might be helpful.


Assuntos
Hepatite C Crônica/patologia , Falência Renal Crônica/patologia , Transplante de Rim/patologia , Fígado/patologia , Carga Viral , Adulto , Alanina Transaminase/sangue , Progressão da Doença , Feminino , Humanos , Cirrose Hepática/patologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Listas de Espera
8.
Gastroenterology ; 117(5): 1164-72, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10535880

RESUMO

BACKGROUND & AIMS: : At least half of patients with chronic hepatitis C virus (HCV) fail to respond to interferon or interferon/ribavirin therapy. Histological improvement is observed in some nonresponders. We conducted a randomized, controlled trial to determine if maintenance interferon therapy could prevent histological progression in this subset of nonresponders. METHODS: Fifty-three patients with chronic HCV were enrolled. All were HCV-RNA positive after 6 months of treatment with interferon alfa-2b but had a histological response. Twenty-seven of the patients were randomly assigned to continue interferon (3 MU 3 times weekly) for 24 months; 26 patients discontinued treatment and were observed prospectively. Alanine aminotransferase (ALT) level and HCV-RNA titer were monitored, and liver biopsy was repeated every 12 months. RESULTS: Before interferon therapy, the 2 groups were well matched for all demographic factors, serum ALT (94.0 +/- 15.6), log HCV-RNA titer (5. 85 +/- 0.15 copies/mL), histology score (9.5 +/- 0.2), and percentage with cirrhosis (25%). After 6 months of treatment, significant reductions (P < 0.05) in serum ALT level (62.6 +/- 9.6), log HCV-RNA titer (4.79 +/- 0.13 copies/mL), and hepatic inflammation (4.0 +/- 0.2) were observed. These improvements were maintained in the patients randomized to continue interferon. Stopping treatment was associated with an increase in serum ALT, log HCV-RNA, and hepatic inflammation back to baseline. After 30 months of treatment, mean fibrosis score declined from 2.5 to 1.7 and 80% of patients had histological improvement (P < 0.03). Discontinuation of interferon was associated with an increase in mean fibrosis score from 2.2 to 2.4 and worsening of hepatic histology in 30% of patients (P < 0.01). CONCLUSIONS: These data support the hypothesis that maintenance interferon may prevent histological progression of chronic HCV in patients who remain viremic.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Viremia/tratamento farmacológico , Alanina Transaminase/sangue , DNA Viral/análise , Feminino , Hepacivirus/genética , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes
9.
Hepatology ; 30(3): 602-5, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10462363

RESUMO

The frequency with which florid duct lesions are seen in needle-biopsy specimens of the liver was assessed in patients with primary biliary cirrhosis (PBC) enrolled in a 2-year randomized, double-blind, placebo-controlled trial of ursodeoxycholic acid (UDCA) versus placebo. Paired biopsy specimens obtained at entry and after 2 years on medication were reviewed blindly and mostly simultaneously by a panel of 5 hepatopathologists who, earlier, had characterized the florid duct lesion, which has been well described in the pathology literature. Florid duct lesions at entry were identified in approximately 36%. Patients with earlier disease showed florid duct lesions much more frequently than those with more advanced disease. The prevalence of florid duct lesions in 60 patients receiving placebo medication fell from 38.3% to 21.7%, P =. 025, over the period of 2 years. The prevalence of florid duct lesions also decreased in the 55 patients receiving UDCA, from 32.7% to 18.2%, P =.046. The prevalences of these lesions in the placebo and UDCA patients at entry and at 2 years were not significantly different from each other. The findings suggest that UDCA does not prevent ongoing bile duct destruction in patients with PBC. Instead, they support the impression that UDCA exerts its beneficial effects by protecting against the consequences of bile duct destruction.


Assuntos
Ductos Biliares/efeitos dos fármacos , Cirrose Hepática Biliar/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico , Ductos Biliares/patologia , Método Duplo-Cego , Humanos , Cirrose Hepática Biliar/patologia
10.
Am Surg ; 65(2): 121-4, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9926743

RESUMO

A 24-year-old female patient who had suffered from recurrent bouts of acute pancreatitis for over 3 years was found on endoscopic retrograde cholangiopancreatography to have an aberrant pancreatic duct that terminated in a cyst. An aberrant lobe of pancreas had been discovered at exploratory laparotomy 3 years previously and was left untreated. Excision of the aberrant lobe of pancreas and accompanying gastric duplication cyst was curative. This case illustrates the importance of obtaining endoscopic retrograde cholangiopancreatography in all young individuals with recurrent pancreatitis to detect this rare, but curable, cause of pancreatitis.


Assuntos
Pâncreas/anormalidades , Pancreatite/etiologia , Estômago/anormalidades , Doença Aguda , Adulto , Colangiopancreatografia Retrógrada Endoscópica , Feminino , Humanos , Pancreatectomia , Ductos Pancreáticos/anormalidades , Pancreatite/cirurgia , Recidiva
11.
Int J Surg Investig ; 1(1): 55-66, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-11817338

RESUMO

OBJECTIVE: The study was aimed at determining whether the vasodilator, adenosine, shown to produce dramatic improvement in liver graft and animal acute and long-term survival, would be beneficial in human liver transplantation. METHODS: A prospective, randomized, double-blind trial of an adenosine rinse preservation solution in human orthotopic liver transplantation (OLTX) was conducted in 43 consecutive transplants. Intraoperative and postoperative care was performed by a single transplant team utilizing a quadruple drug immunosuppressive protocol, with complete 5-year patient follow-up. At implantation all allografts were flushed with a 4 degrees C (pH 7.4) Normosol solution, with 0.12 mM adenosine or without adenosine. RESULTS: Recipient characteristics were similar in the treated and control groups including age, pre-OLTX diagnosis, and United Network for Organ Sharing (UNOS) status. Donor variables were equivalent in the two groups including age, weight, prothrombin time, and serum chemistries. Operative variables showed no differences except a significant (p = 0.006) reduction of veno-venous bypass time in the adenosine treated group. Liver allograft function improved in the adenosine rinse groups as measured by both postoperative bile production (218 +/- 156cc/24h adenosine vs. 116 +/- 78 cc/24 h without adenosine, p = 0.03) and Factor 7 production at day 3 (64 +/- 26% adenosine vs. 51 +/- 20% without adenosine, p = 0.08). The adenosine treated group had an insignificant 10% patient and graft improvement in survival at 6 months to 60 months compared to the control group. CONCLUSIONS: These results suggest that adenosine added to the intraoperative flush solution during human liver transplantation is safe, does not reduce cardiac stability at reperfusion, improves early liver allograft function, but has an insignificant short- and long-term affect on allograft survival.


Assuntos
Adenosina/farmacologia , Transplante de Fígado , Soluções para Preservação de Órgãos/farmacologia , Preservação de Órgãos , Irrigação Terapêutica , Adenosina/administração & dosagem , Adulto , Método Duplo-Cego , Feminino , Sobrevivência de Enxerto , Histocompatibilidade , Humanos , Soluções Isotônicas/química , Soluções Isotônicas/farmacologia , Fígado/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Transplante de Fígado/imunologia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Análise de Sobrevida , Doadores de Tecidos , Transplante Homólogo
12.
Hepatology ; 26(3): 780-5, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9303513

RESUMO

The present study was conducted to evaluate the relationship between biochemical, virological, and histological response during the course of interferon therapy. Ninety consecutive patients with well-documented chronic hepatitis C virus (HCV) were treated with 5 MU of interferon alfa-2b three times weekly for 6 months. Liver biopsy was performed, and serum HCV RNA titer was measured before and at the completion of interferon treatment. Normalization of serum alanine transaminase (ALT) concentration (biochemical response) was observed in 50% of patients. In these patients, Knodell score declined significantly from 9.6 +/- 0.5 to 5.0 +/- 0.5 (P < .01), and 75% became HCV RNA negative. The remaining patients (50%) were biochemical nonresponders; mean Knodell score declined from 9.6 +/- 0.5 to 7.7 +/- 0.5 (P < .01), and 11% became HCV RNA negative. For both biochemical responders and nonresponders, the decline in Knodell score was confined to the components of hepatic inflammation (piecemeal necrosis + lobular + portal inflammation); no change in fibrosis was observed. Hepatic inflammation declined by 5 points or more in 69% of biochemical responders and 48% of biochemical nonresponders, and by at least 50% from pretreatment values in 74% and 38% of biochemical responders and biochemical nonresponders, respectively. For all patients (both biochemical responders and nonresponders) who remained viremic at the conclusion of interferon therapy, the reduction in hepatic inflammation was a linear function of the decline in HCV RNA titer. We conclude that more than one third of patients who had no biochemical response after 6 months of interferon therapy achieved a similar improvement in hepatic histology as was observed in patients with biochemical response. This improvement in hepatic histology appeared to correlate with a reduction in HCV RNA titer, especially in patients who remained viremic.


Assuntos
Hepacivirus/genética , Hepatite C/terapia , Interferon-alfa/uso terapêutico , Adulto , Alanina Transaminase/sangue , Biópsia , Feminino , Seguimentos , Hepacivirus/isolamento & purificação , Hepatite C/patologia , Hepatite C/fisiopatologia , Humanos , Inflamação , Interferon alfa-2 , Fígado/patologia , Testes de Função Hepática , Masculino , RNA Viral/sangue , Proteínas Recombinantes , Análise de Regressão , Estudos Retrospectivos
13.
Mol Pharmacol ; 50(1): 10-6, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8700101

RESUMO

Interindividual variation in the spontaneous and in the glucocorticoid-or rifampicin-inducible expression of the CYP3A cytochromes P450, the dominant froms of this supergene family that catalyze the oxidation of numerous drugs and environmental chemicals in human liver, remains largely unexplained, due in part to the lack of a validated animal model. We analyzed the 5'-flanking sequences of CYP3A genes from the rat (CYP3A23, CYP3A2), rabbit (CYP3A6), and human (CYP3A4, CYP3A5, CYP3A7) and found variable regions separated by three areas (consensus I, II, and III) of sequence homology immediately upstream of their respective promoters. We used trans-species gene transfer in cellulo as a new approach for determining the basis for qualitative differences among species in liver expression of different forms of CYP3A. When we transfected into cultured rat hepatocytes vectors containing 5'-flanking DNA from CYP3A23, CYP3A4, or CYP3A6 genes, we found that CAT activity was induced on treatment with dexamethasone or pregnenolone-16 alpha-carbonitrile only if consensus II sequences were included. Rifampicin treatment had no effect. When the same constructions containing consensus II were transfected into rabbit hepatocytes, increased activity was observed on treatment of the cells with dexamethasone or with rifampicin but not with pregnenolone-16 alpha-carbonitrile. These results suggest that the host cellular environment rather than the structure of the gene dictates the pattern of CYP3A inducibility. The application of this new model system will provide a unique technique for identifying mechanisms of induction and advancing the development of appropriate toxicological models for human safety assessment.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450/biossíntese , Glucocorticoides/farmacologia , Fígado/metabolismo , Oxigenases de Função Mista/biossíntese , Ativação Transcricional , Transfecção/métodos , Animais , Sequência de Bases , Células Cultivadas , Cloranfenicol O-Acetiltransferase/biossíntese , Sequência Consenso , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/genética , Dexametasona/farmacologia , Humanos , Masculino , Oxigenases de Função Mista/genética , Modelos Biológicos , Dados de Sequência Molecular , Família Multigênica , Oligodesoxirribonucleotídeos , Plasmídeos , Carbonitrila de Pregnenolona/farmacologia , Regiões Promotoras Genéticas , Coelhos , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/biossíntese , Rifampina/farmacologia , Especificidade da Espécie , Ativação Transcricional/efeitos dos fármacos
14.
Hepatology ; 24(1): 21-6, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8707264

RESUMO

Interferon (IFN) treatment of chronic hepatitis C virus (HCV) is associated with a high rate of relapse. IFN is thought to exert its effect against HCV via direct viral inhibition and immune stimulation. We have hypothesized that relapse following termination of therapy results from the sudden withdrawal of this immune modulatory effect and that gradual reduction in the IFN dose may decrease the incidence of relapse. One hundred six patients with chronic HCV were enrolled into this 24-month controlled, randomized prospective trial. All were treated with 5 mU of interferon-alpha-2b three times a week for 6 months. Patients who achieved biochemical response were randomized to either stop or taper IFN gradually at monthly intervals as follows; 3 mu, 2 mU, 1 mU, and 0.5 mU (all three times a week). 0.5 mU twice weekly and then once weekly. Liver histology was assessed by Knodell index and HCV RNA was measured by a quantitative polymerase chain reaction (PCR) assay. Of the 92 patients who completed the initial 6 months of IFN treatment, 47 (51%) achieved biochemical response. Twenty-one of these patients were randomized to stop IFN treatment and 25 to taper (1 drop-out). At randomization patients were well matched with respect to age, sex, race, serum alanine transaminase (ALT), and liver histology. Biochemical relapse was observed in 19 of 21 (91%) patients who stopped IFN treatment compared with only 60% who tapered IFN (P= .04). Virological relapse occurred in 90% of patients who stopped and only 48% of persons who tapered IFN therapy. At completion of the 24-month study patients who achieved long-term sustained biochemical response had a significantly lower mean Knodell score (3.5 vs. 6.5) and a significantly greater number were HCV RNA negative in serum (85% vs. 18%) compared with relapsers. We conclude that gradual reduction in IFN dose is associated with a significant higher rate of sustained response and clearance of HCV RNA from serum compared with abruptly stopping treatment. This in turn is associated with a significant improvement in hepatic histology supporting the premise that response to IFN therapy can prevent progression to cirrhosis.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/terapia , Interferon-alfa/uso terapêutico , RNA Viral/sangue , Adulto , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Hepatite C/patologia , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Fígado/patologia , Cirrose Hepática/prevenção & controle , Masculino , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Proteínas Recombinantes , Recidiva , Fatores de Tempo
15.
J Biol Chem ; 270(48): 28917-23, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7499421

RESUMO

The induction by dexamethasone of rat liver CYP3A1 differs from classical glucocorticoid gene regulation in part because both glucocorticoids and antiglucocorticoids such as pregnenolone 16 alpha-carbonitrile (PCN) induce CYP3A1 through transcriptional gene activation. In the present study, we transiently expressed in primary cultures of rat hepatocytes plasmids consisting of CYP3A1 5'-flanking sequences fused to a chloramphenicol acetyltransferase reporter plasmid. Deletional analysis identified a 78-base pair (bp) element located approximately 135 bp upstream of the transcriptional start site that was inducible by treatment of the cultures with dexamethasone or PCN and was induced synergistically by dexamethasone plus PCN. Nuclear extract from control rat liver protected two regions within the 78-bp sequence against digestion with DNase I. The same two regions were protected when nuclear extracts from dexamethasone-treated animals were used. Analysis of both of the "footprints" (FP1 and FP2) failed to reveal a classical sequence for the glucocorticoid-responsive element. A 33-bp element that includes FP1 sequences inserted into the chloramphenicol acetyltransferase reporter plasmid and transiently expressed in rat hepatocytes conferred a profile of dexamethasone and PCN induction similar to that of the 78-bp element. However, an Escherichia coli expressed glucocorticoid receptor protein failed to protect sequences within FP1 in DNase I footprinting experiments and failed to change its mobility in gel shift assays. Moreover, as judged by the gel shift assay, the specific protein binding to this fragment was the same whether nuclear extracts from the liver of untreated or dexamethasone-treated rats were used. We conclude that the activation of CYP3A1 gene transcription by glucocorticoids may involve proteins already bound to the controlling element in the CYP3A1 gene through a mechanism in which GR in the presence of hormone does not bind directly to CYP3A1 DNA.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Dexametasona/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Fígado/enzimologia , Oxigenases de Função Mista/genética , Carbonitrila de Pregnenolona/farmacologia , Animais , Sequência de Bases , Células Cultivadas , Cloranfenicol O-Acetiltransferase/genética , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/metabolismo , Dexametasona/antagonistas & inibidores , Fígado/citologia , Masculino , Oxigenases de Função Mista/metabolismo , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/química , Ratos , Ratos Sprague-Dawley , Transativadores/metabolismo , Ativação Transcricional
16.
Hepatology ; 19(4): 933-40, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8138268

RESUMO

Recent advances in the medical and surgical treatment of chronic hepatitis and cirrhosis have made it increasingly important to develop noninvasive tests of liver function. Our study has evaluated the hepatic conversion of lidocaine to its primary metabolite monoethylglycinexylodide and compared this with liver histological findings in 225 patients with chronic hepatitis (161 with hepatitis C, 23 with hepatitis B, 21 with autoimmune hepatitis and 20 with cryptogenic hepatitis). One hundred seven (47.7%) patients had cirrhosis at the time of evaluation. A decline in monoethylglycinexylodide production was observed with worsening liver histological conditions from a mean of 81.5 +/- 7.0 ng/ml in patients with chronic persistent hepatitis to 61.2 +/- 5.5 ng/ml for chronic active hepatitis and 20.9 +/- 1.5 ng/ml in patients with cirrhosis (p < 0.05). A further stepwise decline in monoethylglycine xylodide production was observed with worsening Child class: from 25.5 +/- 2.2 ng/ml for class A patients to 8.9 +/- 1.4 ng/ml for patients with Child class C disease (p < 0.05). All patients with monoethylglycinexylodide production less than 20 ng/ml had cirrhosis confirmed on histological examination. In contrast, no relationship was observed between liver histological status and serum transaminases (AST or ALT), bilirubin, albumin and prothrombin time. Thirty-five patients underwent repeat histological evaluation and monoethylglycinexylodide testing after receiving at least 6 mo treatment for chronic hepatitis (interferon for hepatitis B and C and corticosteroids for autoimmune hepatitis). The change in monoethylglycinexylodide production observed in these patients was a linear function of the change in Knodell histological index (r = 0.73, p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Hepatite/metabolismo , Lidocaína/farmacocinética , Cirrose Hepática/metabolismo , Fígado/metabolismo , Adulto , Idoso , Alanina Transaminase/sangue , Doença Crônica , Feminino , Hepatite/patologia , Humanos , Lidocaína/análogos & derivados , Lidocaína/sangue , Lidocaína/metabolismo , Fígado/patologia , Cirrose Hepática/patologia , Testes de Função Hepática/métodos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
17.
Transplantation ; 57(4): 526-32, 1994 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-8116036

RESUMO

It is well recognized that hepatitis recurs in virtually all patients who undergo orthotopic liver transplantation for cirrhosis secondary to chronic hepatitis C (HCV). The present report describes the biochemical and histologic findings of recurrent hepatitis in 25 such patients. One patient was found to have hepatocellular carcinoma at the time of OLT and was excluded from further analysis. All post-OLT laboratory values were reviewed. Liver biopsies were performed on protocol 6, 12, 24, and 36 months following OLT. Additional biopsies were performed as necessary to evaluate abnormalities in serum liver chemistries. A total of 104 biopsies was obtained; hepatitis consistent with recurrent HCV was present in 68 (65%). Other biopsy findings included cytomegalovirus hepatitis; acute, chronic, or resolving rejection; cholestasis with or without an underlying hepatitis; steatosis, and centrilobular necrosis. Histologic hepatitis appeared in all patients within 12 months following OLT. Despite these histologic findings, serum ALT was normal for prolonged periods in over 50% of such patients. In all cases this hepatitis was mild and did not progress over a mean follow-up of 22 months (maximum 44 months), as judged by Knodell histologic activity score (mean score: 4.0 +/- 0.3). Five patients developed cholestatic jaundice, far out of proportion to the degree of histologic hepatitis. In 2 patients this was secondary to chronic rejection. The other 3 patients had drug-induced cholestasis that resolved after various medications were discontinued. HCV did not contribute to graft dysfunction in any of the 24 patients. To date, our data suggest that post-OLT hepatitis in patients with preexisting HCV is a relatively benign process. Severe cholestatic jaundice in such patients is not secondary to HCV, and should stimulate a search for other possible causes of graft dysfunction. The long-term consequences of recurrent HCV following hepatic transplantation remain to be determined.


Assuntos
Hepatite C/diagnóstico , Transplante de Fígado , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Bilirrubina/sangue , Colestase/etiologia , Feminino , Sobrevivência de Enxerto , Hepatite C/patologia , Humanos , Transplante de Fígado/patologia , Masculino , Pessoa de Meia-Idade , Necrose
18.
Anat Embryol (Berl) ; 185(6): 517-27, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1605364

RESUMO

The extracellular matrix influences organogenesis by modulating cell behavior. In humans, collagen is the major matrix constituent of the adult intestinal wall and is synthesized by smooth muscle cells. The objective of the current study was to examine collagen production by fetal human intestinal smooth muscle cells isolated during intestinal morphogenesis. Techniques were developed for the isolation and culture of human fetal intestinal smooth muscle cells. The cultured cells were confirmed as muscle by immunohistochemical stains for cytoskeletal filaments and documentation of contractile behavior. In culture, these cells stained for mesenchymal and muscle cytoskeletal proteins: vimentin, actin, and desmin, and did not stain for neural or epithelial markers. The muscle cells contracted in response to acetylcholine, in contrast to human fetal dermal fibroblasts which did not contract appreciably. Collagen production was assayed by the uptake of [3H]-proline into collagenase-digestible protein. Collagen production was greatest at 11 weeks gestation, the youngest age studied. By 20 weeks gestation, collagen production had decreased to adult levels. However, when compared to another matrix-producing fetal mesenchymal cell, the dermal fibroblast, intestinal smooth muscle cells produced twice as much collagen. Collagen types were determined by polyacrylamide slab gel electrophoresis. Smooth muscle cells predominantly produced types I and III collagen alpha chains. Therefore, collagen production is a significant function of human fetal intestinal smooth muscle cells, and probably plays a major role in the development of intestinal structure. The in vitro model presented here provides a means of studying the regulation of this collagen production throughout intestinal organogenesis.


Assuntos
Colágeno/biossíntese , Intestinos/embriologia , Músculo Liso/metabolismo , Fibroblastos/metabolismo , Idade Gestacional , Humanos , Imuno-Histoquímica , Mucosa Intestinal/metabolismo
20.
Gastroenterology ; 100(1): 203-11, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1983822

RESUMO

The protective effect of ursodeoxycholate conjugates against bile salt hepatotoxicity was studied in chronic bile fistula rats. Taurochenodeoxycholate or taurodeoxycholate, infused intraduodenally at 24 or 16 mumols/100 g rat per hour, respectively, caused cholestasis and severe hepatocellular necrosis within 8 hours. In contrast, tauroursodeoxycholate or taurocholate at 48 mumols/100 g rat per hour were choleretic. Tauroursodeoxycholate was not hepatotoxic, whereas taurocholate produced moderate hepatocellular necrosis. Simultaneous infusion of tauroursodeoxycholate to rats receiving taurochenoxycholate or taurodeoxycholate preserved bile flow and ameliorated hepatic injury in a dose-dependent manner. Tauroursodeoxycholate protected equally by intravenous and intraduodenal routes. Intravenous glycoursodeoxycholate also was protective. The hydrophobicity index of infused bile salts correlated well with their toxicity. Concurrent administration of ursodeoxycholate conjugates did not reduce biliary recovery of intraduodenally infused [24-14C]-taurocholate. Biliary alkaline phosphatase secretion was stimulated by infusion of taurocholate, taurodeoxycholate, or taurochenodeoxycholate; simultaneous infusion of ursodeoxycholate conjugates failed to prevent this increase. We conclude that ursodeoxycholate counteracts hepatoxicity of more hydrophobic bile salts via a direct effect at the level of the liver.


Assuntos
Colestase/prevenção & controle , Hepatopatias/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico , Animais , Ácidos e Sais Biliares/antagonistas & inibidores , Doença Hepática Induzida por Substâncias e Drogas , Colestase/induzido quimicamente , Colestase/enzimologia , Hepatopatias/enzimologia , Hepatopatias/patologia , Masculino , Necrose/tratamento farmacológico , Ratos , Ratos Endogâmicos
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