Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 93
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Viral Hepat ; 23(2): 80-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353843

RESUMO

UNLABELLED: Grazoprevir (MK-5172, Merck & Co., Inc.) is a selective inhibitor of the hepatitis C virus (HCV) NS3/4a protease. The aim of this study was to evaluate the safety and efficacy of grazoprevir at doses of 25-100 mg/day in combination with peginterferon and ribavirin (PEG-IFN/RBV). In this randomized, dose-ranging, multicentre trial, treatment-naive adults with chronic HCV genotype 1 infection received once-daily grazoprevir 25 mg, 50 mg or 100 mg plus PEG-IFN/RBV for 12 weeks. Patients with quantifiable HCV RNA (≥25 IU/mL) at week 4 received an additional 12 weeks of PEG-IFN/RBV. The primary endpoint was sustained virologic response (HCV RNA <25 IU/mL 12 weeks after completing therapy [SVR12]). Eighty-seven patients were randomly assigned and received ≥1 dose of therapy. Median time to undetectable HCV RNA was 16 days in the 100-mg arm and 22 days in the 25- and 50-mg arms. All patients except one had HCV RNA undetectable or unquantifiable at week 4 and received 12 weeks of therapy. SVR12 was achieved by 13 of 24 (54.2%), 21 of 25 (84.0%) and 23 of 26 (88.5%) patients in the 25-, 50- and 100-mg arms, respectively (per-protocol analysis). Three patients discontinued as a result of nonserious adverse events (AEs) and three patients experienced serious AEs. Transaminase elevations occurred in two patients (one each in the 25- and 100-mg arms). CONCLUSION: These data support further study of the grazoprevir 100-mg dose. Phase 3 studies of grazoprevir 100 mg in combination with elbasvir are currently ongoing (NCT01710501; protocol P038).


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Quinoxalinas/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Amidas , Carbamatos , Ciclopropanos , Quimioterapia Combinada/efeitos adversos , Feminino , Genótipo , Hepacivirus/genética , Humanos , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Quinoxalinas/efeitos adversos , RNA Viral , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Ribavirina/efeitos adversos , Sulfonamidas , Carga Viral , Proteínas não Estruturais Virais/antagonistas & inibidores , Adulto Jovem
2.
Dig Dis Sci ; 61(6): 1728-34, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26781427

RESUMO

BACKGROUND: Overt hepatic encephalopathy (OHE) is a frequent complication of decompensated cirrhosis. AIMS: A multicenter prospective observational study was performed to assess the most commonly recorded presenting manifestations of OHE and its associated health-care burden. METHODS: Qualifying patients must have experienced ≥1 OHE episode within 30 days of enrollment (qualifying OHE) and were followed for recurrence (on-study OHE). RESULTS: Two hundred and sixty-five patients were enrolled at 30 sites and followed for up to 9 months (mean 72 days). Seventy-two patients experienced 122 on-study episodes; with 72, 23, and 13 having ≥1, ≥2, or ≥3 on-study episodes with median days to occurrence of the 1st, 2nd, and 3rd episode of 34, 19, and 11, respectively. The most frequently recorded OHE manifestations included confusion (78 %), change in mental status (57 %), disorientation (48 %), lethargy (46 %), and asterixis (45 %). West Haven grade was used inconsistently and recorded for only 28 % of episodes. Most qualifying and on-study episodes occurred on rifaximin (60 and 82 %, respectively) and were associated with hospitalization (68 and 85 %, respectively). Twenty-three patients experienced ≥2 on-study episodes within 2 months of enrollment on average (median 45 days) and accounted for 60 % of on-study episodes. CONCLUSIONS: In this prospective study, OHE's most commonly recorded presenting manifestations included confusion, altered mental status, disorientation, lethargy, and asterixis. As reflected by frequent recurrence and hospitalizations, OHE, particularly the approximately 10 % of "high-resource-utilizing" patients with frequent recurrence, continues to pose a major unmet medical need and health-care burden despite the use of rifaximin.


Assuntos
Encefalopatia Hepática/patologia , Cirrose Hepática/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Rifamicinas/administração & dosagem , Rifamicinas/farmacologia , Rifaximina , Adulto Jovem
3.
Mol Genet Metab ; 110(4): 446-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24144944

RESUMO

BACKGROUND: Phenylacetic acid (PAA) is the active moiety in sodium phenylbutyrate (NaPBA) and glycerol phenylbutyrate (GPB, HPN-100). Both are approved for treatment of urea cycle disorders (UCDs) - rare genetic disorders characterized by hyperammonemia. PAA is conjugated with glutamine in the liver to form phenylacetyleglutamine (PAGN), which is excreted in urine. PAA plasma levels ≥ 500 µg/dL have been reported to be associated with reversible neurological adverse events (AEs) in cancer patients receiving PAA intravenously. Therefore, we have investigated the relationship between PAA levels and neurological AEs in patients treated with these PAA pro-drugs as well as approaches to identifying patients most likely to experience high PAA levels. METHODS: The relationship between nervous system AEs, PAA levels and the ratio of plasma PAA to PAGN were examined in 4683 blood samples taken serially from: [1] healthy adults [2], UCD patients of ≥ 2 months of age, and [3] patients with cirrhosis and hepatic encephalopathy (HE). The plasma ratio of PAA to PAGN was analyzed with respect to its utility in identifying patients at risk of high PAA values. RESULTS: Only 0.2% (11) of 4683 samples exceeded 500 µg/ml. There was no relationship between neurological AEs and PAA levels in UCD or HE patients, but transient AEs including headache and nausea that correlated with PAA levels were observed in healthy adults. Irrespective of population, a curvilinear relationship was observed between PAA levels and the plasma PAA:PAGN ratio, and a ratio>2.5 (both in µg/mL) in a random blood draw identified patients at risk for PAA levels>500 µg/ml. CONCLUSIONS: The presence of a relationship between PAA levels and reversible AEs in healthy adults but not in UCD or HE patients may reflect intrinsic differences among the populations and/or metabolic adaptation with continued dosing. The plasma PAA:PAGN ratio is a functional measure of the rate of PAA metabolism and represents a useful dosing biomarker.


Assuntos
Glutamina/análogos & derivados , Encefalopatia Hepática/sangue , Fenilacetatos/sangue , Distúrbios Congênitos do Ciclo da Ureia/sangue , Biomarcadores/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Glutamina/administração & dosagem , Glutamina/sangue , Glicerol/administração & dosagem , Glicerol/análogos & derivados , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/patologia , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Fenilacetatos/administração & dosagem , Fenilbutiratos/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Distúrbios Congênitos do Ciclo da Ureia/epidemiologia , Distúrbios Congênitos do Ciclo da Ureia/etiologia , Distúrbios Congênitos do Ciclo da Ureia/patologia
4.
J Clin Invest ; 89(6): 2040-5, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1318328

RESUMO

Diagnostic testing for hepatitis C virus (HCV) infection currently is based on the presence of anti-HCV antibodies or a positive HCV RNA polymerase chain reaction (PCR) test. Although HCV RNA PCR is a sensitive and specific technique, widespread application is limited. Moreover, HCV RNA PCR is subject to false-positive reactions through contamination and is inherently difficult to standardize and quantitate. To overcome limitations of HCV RNA PCR, we produced both cDNA and riboprobes from a 241 nucleotide sequence of the 5' untranslated region of the HCV genome for slot hybridization. Hybridization was absent using normal human serum, horse serum, or hepatic cellular RNA from noninfected liver. Hybridization occurred predominantly with positive-stranded HCV RNA and was abolished by pretreatment with RNase A. Slot hybridization was performed on serum samples from 60 patients with chronic HCV infection and a positive HCV RNA PCR and 20 patients with liver diseases unrelated to HCV who had a negative HCV RNA PCR. Slot hybridization with cDNA and riboprobes showed concordance with HCV RNA PCR of 95 and 98.3%, respectively. There were no false-positive reactions in controls. The sensitivity of riboprobe hybridization was comparable to that of one stage HCV RNA PCR using 5' untranslated region primers. Riboprobe hybridization with the HCV H strain standard was positive in the dilution corresponding to 10(-6) chimpanzee infectious doses50/ml. The density of the hybridization signals correlated significantly with the mass of an RNA standard extracted from the liver of a patient with HCV infection. The relative quantities of HCV RNA in the sera of selected patients varied and were not correlated with the duration of disease or the histopathological stage. The highest relative quantities were associated with concurrent immunosuppression. We conclude that slot hybridization is a sensitive, specific alternative to HCV RNA PCR that can be directly quantitated using appropriate HCV RNA standards.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/diagnóstico , Sondas RNA , RNA Viral/isolamento & purificação , Sequência de Bases , Northern Blotting , Clonagem Molecular , DNA Viral , Hepacivirus/genética , Hepatite C/microbiologia , Humanos , Íntrons , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
5.
J Clin Invest ; 62(5): 1069-77, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-711852

RESUMO

An approach to the assessment of reticuloendothelial function that quantitates clearance specifically mediated by membrane receptors for C3b and immunoglobulin (Ig)G has been applied in man. Clearance of isologous erythrocytes coated with IgM or C3b or coated with IgG were examined in patients with primary biliary cirrhosis (PBC), chronic hepatitis, or alcoholic cirrhosis and normal control subjects and compared with the clearance of aggregated human serum albumin. Clearance of these three types of particles varied independently. None of the patients studied had a defect in the clearance of aggregated albumin. No patient with PBC (0:6) had delayed clearance of IgG-coated erythrocytes; one of six patients with chronic hepatitis had delayed clearance of these cells. Indeed, four of six with PBC had increased rates of IgG-mediated clearance. In contrast, six out of six patients with PBC had an unequivocal defect in clearance mediated by C3b receptors. The patients with PBC varied widely in terms of duration of symptoms, degree of cholestasis, and histologic stage of disease. No defect of C3b-mediated erythrocyte clearance was found in the patients with chronic hepatitis or alcoholic cirrhosis. Furthermore, a patient with severe cholestasis secondary to large duct biliary obstruction exhibited normal C3b-mediated clearance. The defect in C3b-mediated clearance in PBC did not correlate with serum levels of individual complement components or inhibitors or with the presence of circulating immune complexes as measured by the Clq precipitation assay. Thus, measurements of receptor specific clearance, but not clearance of aggregated proteins, have revealed a highly specific defect in reticuloendothelial function in PBC.


Assuntos
Complemento C3b/metabolismo , Cirrose Hepática Biliar/imunologia , Sistema Fagocitário Mononuclear/metabolismo , Adolescente , Adulto , Sítios de Ligação , Doença Crônica , Feminino , Hepatite/imunologia , Humanos , Imunoglobulina G , Cirrose Hepática Alcoólica/imunologia , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Sistema Fagocitário Mononuclear/imunologia
6.
J Clin Invest ; 60(5): 1116-28, 1977 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-332716

RESUMO

The in vitro cytotoxic function and target cell specificity of peripheral blood lymphocytes from selected patients with primary biliary cirrhosis and hepatitis B surface antigen-negative chronic hepatitis were investigated using 51Cr-labeled human Chang and EL-4 mouse sarcoma cell targets in assays of spontaneous cell-mediated cytotoxicity (SCMC) and mitogen-induced cellular cytotoxicity (MICC). In addition, antibody-dependent cellular cytotoxicity (ADCC) against Chang cells was assessed. At an effector-to-target cell ration of 100:1, the mean SCMC against Chang cells was much less in patients with primary biliary cirrhosis than that in either the controls (P less than 0.001) or the patients with chronic hepatitis (P less than 0.005) whereas the value for patients with chronic hepatitis did not differ significantly from that of the controls. The mean SCMC against EL-4 mouse sarcoma cells was also less in patients with primary biliary cirrhosis than in controls (P less than 0.005) whereas the value for chronic hepatitis was not significantly different from that of the controls or patients with primary biliary cirrhosis. In contrast, MICC against both targets and ADCC against Chang cells were similar for each group. Comparison of SCMC and MICC against both target cells, measured simultaneously, showed similar cytotoxic potenital against both target cells for each group. Effector cells capable of mediating cytotoxicity in each assay were defined by testing the cytotoxic function of lymphocyte subpopulations isolated from two representative patients with each disease using techniques of immunoabsorbent affinity chromatography and Fc receptor binding to antigen-antibody complexes. In both primary biliary cirrhosis and chronic hepatitis SCMC and ADCC were mediated by a subpopulation of lymphocytes which lack surface immunoglobulin (sIg-) and bear Fc receptors (Fc+). In contrast, MICC was mediated by sIg- cells which lack Fc receptors. Lymphocytes bearing sIg- were not cytotoxic in any assay. These results establish a difference in cytotoxic function in primary biliary cirrhosis and chronic hepatitis by defining the presence of a defect in spontaneous cytotoxic function of sIg-, Fc+ lymphocytes against Chang cells in primary biliary cirrhosis.


Assuntos
Citotoxicidade Imunológica , Hepatite/imunologia , Cirrose Hepática Biliar/imunologia , Adulto , Animais , Citotoxicidade Celular Dependente de Anticorpos , Células Cultivadas , Doença Crônica , Testes Imunológicos de Citotoxicidade , Feminino , Antígenos de Superfície da Hepatite B , Humanos , Fragmentos Fc das Imunoglobulinas , Técnicas de Imunoadsorção , Técnicas In Vitro , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos B , Sarcoma Experimental/imunologia , Tripsina/farmacologia
7.
Aliment Pharmacol Ther ; 45(5): 723-732, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28004405

RESUMO

BACKGROUND: High-quality data on the management of autoimmune hepatitis (AIH) are scarce. Despite published guidelines, management of AIH is still expert based rather than evidence based. AIM: To survey expert hepatologists, asking each to describe their practices in the management of patients with AIH. METHODS: A survey questionnaire was distributed to members of the International AIH Group. The questionnaire consisted of four clinical scenarios on different presentations of AIH. RESULTS: Sixty surveys were sent, out of which 37 were returned. None reported budesonide as a first line induction agent for the acute presentation of AIH. Five (14%) participants reported using thiopurine S-methyltransferase measurements before commencement of thiopurine maintenance therapy. Thirteen (35%) routinely perform liver biopsy at 2 years of biochemical remission. If histological inflammatory activity is absent, four (11%) participants reduced azathioprine, whereas 10 (27%) attempted withdrawal altogether. Regarding the management of difficult-to-treat patients, mycophenolate mofetil is the most widely used second-line agent (n = ~450 in 28 centres), whereas tacrolimus (n = ~115 in 21 centres) and ciclosporin (n = ~112 in 18 centres) are less often reported. One centre reported considerable experience with infliximab, while rescue therapy with rituximab has been tried in seven centres. CONCLUSIONS: There is a wide variation in the management of patients with autoimmune hepatitis even among the most expert in the field. Although good quality evidence is lacking, there is considerable experience with second-line therapies. Future prospective studies should address these issues, so that we move from an expert- to an evidence- and personalised-based care in autoimmune hepatitis.


Assuntos
Hepatite Autoimune/tratamento farmacológico , Imunossupressores/uso terapêutico , Azatioprina/uso terapêutico , Biópsia , Budesonida/uso terapêutico , Ciclosporina/uso terapêutico , Pesquisas sobre Atenção à Saúde , Humanos , Metiltransferases/metabolismo , Ácido Micofenólico/uso terapêutico , Rituximab/uso terapêutico , Tacrolimo/uso terapêutico
8.
Aliment Pharmacol Ther ; 42(7): 829-44, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26238707

RESUMO

BACKGROUND: Alisporivir (ALV) is an oral, host-targeting agent with pangenotypic anti-hepatitis C virus (HCV) activity and a high barrier to resistance. AIM: To evaluate efficacy and safety of ALV plus peginterferon-α2a and ribavirin (PR) in treatment-naïve patients with chronic HCV genotype 1 infection. METHODS: Double-blind, randomised, placebo-controlled, Phase 3 study evaluating ALV 600 mg once daily [response-guided therapy (RGT) for 24 or 48 weeks or 48 weeks fixed duration] or ALV 400 mg twice daily RGT with PR, compared to PR alone. Following a Food and Drug Administration partial clinical hold, ALV/placebo was discontinued and patients completed treatment with PR only. At that time, 87% of patients had received ≥12 weeks and 20% had received ≥24 weeks of ALV/PR triple therapy. RESULTS: A total of 1081 patients were randomised (12% cirrhosis, 55% CT/TT IL28B). Addition of ALV to PR improved virological response in a dose-dependent fashion. Overall, sustained virological response (SVR12; primary endpoint) was 69% in all ALV groups vs. 53% in PR control. Highest SVR12 (90%) was achieved in patients treated with ALV 400 mg twice daily and PR for >24 weeks. Seven cases of pancreatitis were reported, with similar frequency between ALV/PR and PR control groups (0.6% vs. 0.8% respectively). Adverse events seen more frequently with ALV/PR than with PR alone were anaemia, thrombocytopenia, hyperbilirubinaemia and hypertension. CONCLUSIONS: Alisporivir, especially the 400 mg twice daily regimen, increased efficacy of PR therapy in treatment-naïve patients with HCV genotype 1 infection. The mechanism of action and pangenotypic activity suggest that alisporivir could be useful in interferon-free combination regimens.


Assuntos
Antivirais/administração & dosagem , Ciclosporina/administração & dosagem , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Adolescente , Adulto , Idoso , Antivirais/efeitos adversos , Ciclosporina/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Ribavirina/efeitos adversos , Resultado do Tratamento , Estados Unidos , Adulto Jovem
9.
Clin Liver Dis ; 3(3): 571-84, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11291239

RESUMO

Currently available evidence is insufficient to classify PBC and AIC as separate diseases. The ultimate answer to the question of whether AIC, defined as AMA-negative PBC with ANA or SMA, is a disease distinct from AMA-positive PBC with or without ANA will require a detailed comparison of etiologic factors and pathogenetic mechanisms, once they are elucidated. It is intriguing to consider the suggestion of Heathcote that the term autoimmune cholangitis be adopted to describe PBC with or without detectable AMA. However, it is improbable that the venerable term PBC will be supplanted. Hepatologists will probably continue to use the terms AIC and AMA-negative PBC interchangeably, with little risk of being misunderstood.


Assuntos
Doenças Autoimunes/imunologia , Doenças Biliares/imunologia , Anticorpos Antinucleares/análise , Doenças Autoimunes/terapia , Doenças Biliares/terapia , Anidrases Carbônicas/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Mitocôndrias/imunologia
10.
Aliment Pharmacol Ther ; 19(9): 1033-9, 2004 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15113371

RESUMO

BACKGROUND: Sirolimus is a potent immunosuppressive medication that acts by inhibiting T-cell proliferation. It has been used in kidney transplantation because of its lack of nephrotoxicity. It is now being investigated in liver transplantation, but there are concerns about safety and long-term side effects such as dyslipidaemia. Hypertriglyceridaemia is a common adverse event seen with sirolimus use, and often does not respond to dose reduction or anti-lipemic drugs. METHOD: We report six patients who have developed significant hyperlipidaemia while receiving sirolimus, in spite of therapeutic trough levels. CONCLUSION: All six patients showed either resolution or improvement in lipid levels with discontinuation of sirolimus.


Assuntos
Hiperlipidemias/induzido quimicamente , Imunossupressores/efeitos adversos , Transplante de Rim , Sirolimo/efeitos adversos , Adulto , Idoso , Ciclosporina/uso terapêutico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tacrolimo/uso terapêutico
11.
Hum Pathol ; 27(11): 1161-5, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8912825

RESUMO

Polymerase chain reaction (PCR) has been used to study liver biopsy tissue in patients with known or suspected hepatitis C virus (HCV). Recent studies of cryptogenic cirrhosis using PCR have been based on study of sera, and HCV has not been shown. The failure to show HCV in patients so studied has left unanswered the question of whether or not patients with cryptogenic cirrhosis could still harbor the virus in the liver. The authors studied liver tissue, obtained at the time of orthopic liver transplantation from 10 patients clinically diagnosed as having end-stage liver disease without demonstrable origin, so-called cryptogenic cirrhosis, using reverse transcription (RT)-PCR to try to recover HCV-RNA. Formalin-fixed, paraffin-embedded tissue was used. For comparison, the authors also studied similarly obtained samples from 10 patients with typical hepatitis C-associated cirrhosis and 10 patients with end-stage liver disease resulting from autoimmune hepatitis. The authors recovered HCV-RNA from 9 of 10 livers from patients with cirrhosis resulting from HCV, and 3 of 10 livers from patients with autoimmune hepatitis. HCV-RNA was not recovered from any of the livers of the 10 patients designated as having cryptogenic cirrhosis.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/virologia , Cirrose Hepática/virologia , Fígado/virologia , RNA Viral/análise , Adolescente , Adulto , Idoso , Doenças Autoimunes/patologia , Doenças Autoimunes/virologia , Feminino , Hepatite/patologia , Hepatite/virologia , Hepatite C/patologia , Humanos , Fígado/patologia , Fígado/cirurgia , Cirrose Hepática/patologia , Cirrose Hepática/cirurgia , Transplante de Fígado/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos
12.
Best Pract Res Clin Gastroenterol ; 15(4): 591-610, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11492970

RESUMO

Since the aetiopathogenesis of primary sclerosing cholangitis (PSC) in humans remains undefined, investigators have studied a variety of animal models to gain insights into immunopathogenetic mechanisms associated with obliterative fibrous cholangitis of intra- and extra-hepatic bile ducts. To date, no animal model has been developed that exhibits all of the attributes of PSC. Rodent models instigated by bacterial cell components or colitis are promising because they may help to explain the strong association between PSC and inflammatory bowel disease (IBD). Other models of direct injury to biliary epithelia, peribiliary vascular endothelia or portal venous endothelia indicate that inflammation, chemokines and cytokines can produce diffuse sclerosis of bile ducts. Models of toxic, infectious or intra-luminal injury of the biliary tract also exhibit focal biliary sclerosis mediated by inflammation and cytokines. The histopathology of several models suggests a sequence of events beginning with secretion of proinflammatory cytokines by activated hepatic macrophages followed by peribiliary infiltration with CD4 and CD8 T cells with a T helper 1 phenotype. These results strongly suggest co-ordinated, pathogenetic roles for both the innate and adaptive immune responses. However, the stimuli that initiate and perpetuate peribiliary fibrosis remain unknown. Interestingly, several models are also associated with the development of anti-neutrophil cytoplasmic antibodies that react in a perinuclear and cytoplasmic pattern similar to that observed in patients with ulcerative colitis and/or PSC. Finally, models of extra-hepatic biliary obstruction continue to provide important information about the pathogenesis of portal fibrosis and secondary biliary cirrhosis that occurs in PSC and other diseases with obstruction of bile flow. Future studies in either existing or new animal models should advance our understanding of the pathogenesis of PSC, the major prerequisite for the development of effective therapies.


Assuntos
Colangite Esclerosante/imunologia , Animais , Infecções Bacterianas/complicações , Modelos Animais de Doenças , Humanos , Camundongos , Ratos
13.
Am Surg ; 62(10): 835-9, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8813166

RESUMO

Variceal bleeding (VB) and ascites refractory to diuretics (RA) represent a significant cause of morbidity and mortality in patients with portal hypertension. Transjugular intrahepatic portosystemic shunts (TIPS) have been used effectively in patients with these complications, especially those individuals awaiting orthotopic liver transplantation (OLT). From April 1992 to July 1995, 41 adult patients underwent an attempt at TIPS placement for refractory VB or ascites at Cedars-Sinai Medical Center. Technical success was achieved in 37 of 41 cases (90.3%) with only two technical complications. Immediate control of hemorrhage and significant improvement of ascites was obtained in 91.9% and 83.5% of the patients, respectively. Six patients (16.2%) died within a week of TIPS placement due to uncontrollable ascites and multiorgan failure. Four of 31 patients (12.9%) developed mild to moderate grades of hepatic encephalopathy that was controlled with lactulose. Rebleeding from recurrent portal hypertension was noted in 5 of 31 cases (16.1%). Shunt stenosis or occlusion was seen in 7 of 31 cases (22.6%) at an average of 6.3 months following TIPS placement. Six patients underwent OLT within an average of 87 days after TIPS. These results indicate that TIPS appears to be an effective method for treatment of refractory VB and RA, especially for patients who are poor candidates for a surgical shunt or awaiting OLT. However, TIPS may not be considered a definitive solution for all patients with portal hypertension because of its current rate of shunt occlusion or stenosis.


Assuntos
Hipertensão Portal/cirurgia , Transplante de Fígado , Derivação Portossistêmica Transjugular Intra-Hepática , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipertensão Portal/fisiopatologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento
14.
Int J Artif Organs ; 25(12): 1189-93, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12518964

RESUMO

Hepatitis C virus infection (HCV) is common in patients with end-stage renal disease (ESRD) and long observation periods have shown the detrimental effect of HCV infection on patient and graft survival after renal transplantation. At present, interferon is the most important agent for the treatment of hepatitis C in ESRD; however, limited information exists concerning the long-term response of patients who undergo renal transplantation after successful antiviral therapy. We describe the evolution of HCV infection in a dialysis patient with hepatitis C who was successfully treated with interferon alpha and then underwent renal transplantation. He received aggressive immunosuppression during the induction phase and for allograft rejection; however, regular screening showed complete absence of biochemical and virological relapse of HCV over a 6-year post-transplantation period. We conclude that interferon can offer excellent response in selected dialysis patients with hepatitis C. Alternative strategies with newer antiviral agents are currently under active investigation.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/isolamento & purificação , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Falência Renal Crônica/terapia , Transplante de Rim , Adulto , Rejeição de Enxerto , Hepacivirus/genética , Hepatite C/complicações , Hepatite C/microbiologia , Humanos , Falência Renal Crônica/complicações , Masculino , Diálise Peritoneal , Reação em Cadeia da Polimerase , Indução de Remissão
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA