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2.
J Clin Gastroenterol ; 43(4): 374-81, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19098685

RESUMO

GOALS: To describe the mechanisms of severe hepatocellular injury with apoptosis in 2 patients receiving hepatitis C virus (HCV)-796. BACKGROUND: HCV-796 is a hepatitis C polymerase inhibitor approved by the US Food and Drug Administration for a phase 2 study of the treatment of hepatitis C in combination with PEG-Interferon and ribavirin. RESULTS: The injury occurred after more than 12 weeks of treatment, with a >20-fold increase in serum alanine aminotransferase and aspartate aminotransferase, and a marked increase in total (and direct) bilirubin in the absence of cholestasis. There was no evidence of autoimmune or viral hepatitis. Involvement of the mitochondrial apoptotic pathway was demonstrated by (1) release of cytochrome C into the cytosol; (2) association of cytochrome C with apoptotic protease activating factor-1 in the cytosol; (3) activation of initiator caspase 9; (4) activation of effector caspase 3; (5) increased serum caspase-3 cleaved cytokeratin-18 peptide; (6) nuclear fragmentation; (7) mitochondrial structural abnormalities; (8) expression of light chain 3 B, an indicator of autophagy; (9) probable autophagy of mitochondria by autophagosomes; and (10) probable phagocytosis of apoptotic hepatocytes by activated macrophages. Immunoglobulin G immune complexes were identified in the hepatocytes and localized to the endoplasmic reticulum and Golgi of these patients after the drug-induced liver disease, reflecting a primary or secondary target. Hepatitis C treatment was discontinued at weeks 15 and 19 in patients 1 and 2, respectively. After more than 6 months off the medication, both patients normalized the serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin with undetectable HCV RNA. CONCLUSIONS: HCV-796 may cause severe hepatocellular injury and apoptosis, with a marked immune reaction in susceptible patients.


Assuntos
Antivirais/efeitos adversos , Apoptose , Benzofuranos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Hepatócitos/patologia , Sulfonamidas/efeitos adversos , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Benzofuranos/administração & dosagem , Benzofuranos/uso terapêutico , Quimioterapia Combinada , Hepacivirus/enzimologia , Hepatite C/virologia , Humanos , Interferons/administração & dosagem , Interferons/uso terapêutico , Fígado/citologia , Fígado/patologia , Hepatopatias/imunologia , Hepatopatias/patologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/uso terapêutico , Ribavirina/administração & dosagem , Ribavirina/uso terapêutico , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico
3.
Am J Gastroenterol ; 103(7): 1810-23, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18564122

RESUMO

The prevalence of hepatitis C virus (HCV) infection is higher among veterans than nonveterans, but only about 14% of all identified infected veterans have ever received antiviral therapy. High rates of comorbid psychiatric and substance use disorders are major barriers to receiving antiviral treatment for veterans, and characteristics associated with poor virologic response are more common in this population. However, accumulating evidence indicates that patients with psychiatric and substance use disorders can successfully receive interferon-based antiviral therapies in an integrated or multidisciplinary health-care setting. The broad aims of integrated care models include reducing fragmentation and improving continuity and coordination of care. Although, to date, there are no randomized controlled trials of specific care models for patients with HCV, studies of integrated care for other chronic diseases suggest several strategies for optimizing outcomes for patients with HCV. Components of an HCV clinic incorporating these principles have been tested in a nonrandomized setting and include routine screening of all patients for psychiatric and substance use disorder risk factors, collaboration with mental health providers within the HCV clinic, following a defined integrated medical/psychiatric clinical protocol, provision of ongoing integrated support during antiviral treatment or retreatment, and educating patients on principles of chronic disease self-management.


Assuntos
Hepatite C Crônica/terapia , Equipe de Assistência ao Paciente , Veteranos , Humanos , Serviços de Saúde Mental , Modelos Teóricos , Transtornos Relacionados ao Uso de Substâncias/terapia , Estados Unidos
4.
J Clin Gastroenterol ; 41 Suppl 3: S318-22, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17975483

RESUMO

Variceal rebleeding is a very frequent and severe complication in cirrhotic patients; therefore, its prevention should be mandatory. Lately several studies demonstrated that the rate of rebleeding was decreased by 40% and overall survival is improved by 20% with beta-blockers. However, this treatment presents some problems, such as the number of nonresponders and contraindications for its use. Recent trials found that the combination of beta-blockers with mononitrate of isosorbide to be superior to beta-blockade alone. Furthermore, endoscopic band ligation also shown to decrease the frequency of rebleeding, complications, and death compared with sclerotherapy and should be the preferred endoscopic treatment. In addition, the comparison between combined pharmacologic treatment with endoscopic treatment present similar rebleeding and mortality rates. More recently, the addition of nadolol to endoscopic band ligation increased the efficacy of endoscopy alone in the prevention of variceal rebleeding. These studies suggest that banding plus drugs could be the treatment of choice for the prophylaxis of rebleeding. When these treatments fail, the recommendation is to use transjugular intrahepatic portosystemic shunt (TIPS) or surgical shunts. Both treatments are effective in preventing rebleeding; however, they are associated with a greater risk of encephalopathy. The comparison of portacaval shunts with TIPS demonstrated that TIPS patients presented higher rebleeding, treatment failure, and transplantation. Another randomized controlled trial comparing distal splenorenal shunt with TIPS shows that variceal rebleeding was similar in both groups without differences in encephalopathy and mortality. The only difference observed was the higher rate of reintervention observed in the TIPS group to maintain his patency.


Assuntos
Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/terapia , Técnicas Hemostáticas , Hipertensão Portal/complicações , Cirrose Hepática/complicações , Antagonistas Adrenérgicos beta/uso terapêutico , Terapia Combinada , Endoscopia , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/fisiopatologia , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/fisiopatologia , Hemostáticos/uso terapêutico , Humanos , Hipertensão Portal/etiologia , Hipertensão Portal/fisiopatologia , Hipertensão Portal/terapia , Dinitrato de Isossorbida/análogos & derivados , Dinitrato de Isossorbida/uso terapêutico , Ligadura , Cirrose Hepática/fisiopatologia , Cirrose Hepática/terapia , Derivação Portocava Cirúrgica , Pressão na Veia Porta , Derivação Portossistêmica Transjugular Intra-Hepática , Guias de Prática Clínica como Assunto , Escleroterapia , Prevenção Secundária , Falha de Tratamento , Resultado do Tratamento
5.
Am J Physiol Gastrointest Liver Physiol ; 288(5): G914-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15626729

RESUMO

We report our experience with an ultrasound system to measure esophageal varix pressure in an in vitro model. The ultrasound system consists of a 12.5 MHz frequency intraluminal ultrasound probe, a water infusion catheter, and a manometry catheter, all contained within a nondistensible latex bag. Esophagi and external jugular veins were harvested from five pigs. The vein and ultrasound system were placed inside the esophagus. One end of the vein was connected to a water reservoir to modulate its pressure; the other end was connected in two different ways to simulate hydrodynamic and hydrostatic flow conditions. The bag was inflated with water until vein occlusion was discernible on the ultrasound images. The influences of vein pressure, vein cross-sectional area and esophageal elasticity on the ultrasound measurement of vein pressure were assessed. A total of 108 trials were performed at nine different vein pressures. Complete vein occlusion occurred when the bag pressure was slightly greater (1.4 +/- 0.7 mmHg) than the vein pressure. For a vein pressure of 25 mmHg, the average occlusion and opening pressures were 27 +/- 0.2 and 25.7 +/- 0.3 mmHg, respectively (P < .05) suggesting that the vein opening pressure on the ultrasound images is more accurate than the vein closing pressure. In conclusion, the ultrasound technique can accurately measure intravariceal pressure in vitro. The bag pressure at the point of vein reopening is the best determinant of the vein pressure.


Assuntos
Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/fisiopatologia , Esôfago/irrigação sanguínea , Manometria/instrumentação , Animais , Suínos , Transdutores de Pressão , Ultrassonografia , Veias
9.
Acta gastroenterol. latinoam ; 34(2): 88-95, 2004.
Artigo em Espanhol | BINACIS | ID: bin-38604
10.
Hepatology ; 37(2): 359-65, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12540786

RESUMO

Treatment with beta-blockers fails to decrease portal pressure in nearly 40% of cirrhotic patients. Recent studies have suggested that treatment with spironolactone reduces pressure and flow in the portal and variceal systems. This trial was designed to assess if nadolol plus spironolactone is more effective than nadolol alone to prevent the first variceal bleeding. One hundred patients with medium and large varices who had never bled and were without ascites were included in a prospective, randomized, multicenter, double-blind, placebo-controlled trial. The patients were randomized into 2 groups: 51 received nadolol plus placebo (N + P) and 49 received nadolol plus spironolactone 100 mg/d (N + S). Hepatic venous pressure gradient (HVPG) and activity of the renin-aldosterone system (plasma renin activity/plasma aldosterone levels) were measured in 24 patients. There were no significant differences in the appearance of variceal bleeding and ascites between groups at a mean follow-up of 22 +/- 16 months. However, analyzing both complications together, the incidence was significantly higher in the N + P group than in the N + S group (39% vs. 20%; P <.04). Clinical ascites was also higher in patients in the N + P group than in the N + S group (21% vs. 6%; P <.04). Significant increases in plasma renin activity and plasma aldosterone levels were only observed in patients in the N + S group (P <.01). The cumulative probabilities of remaining free of bleeding and ascites were similar in both groups after 70 months of follow-up. In conclusion, these results suggest that nadolol plus spironolactone does not increase the efficacy of nadolol alone in the prophylaxis of the first variceal bleeding. However, when bleeding and ascites were considered together, the combined therapy effectively reduced the incidence of both portal-hypertensive complications.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Varizes Esofágicas e Gástricas/etiologia , Hemorragia/etiologia , Hemorragia/prevenção & controle , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Nadolol/uso terapêutico , Espironolactona/uso terapêutico , Idoso , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Circulação Esplâncnica/efeitos dos fármacos , Resultado do Tratamento
11.
Gastroenterology ; 122(4): 916-22, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11910343

RESUMO

BACKGROUND & AIMS: Postprandial increases in portal pressure may influence esophageal variceal rupture. The effects of chronic propranolol and octreotide (100 and 200 microg subcutaneously in a single dose) on postprandial hemodynamics were evaluated. METHODS: FIRST STUDY: 36 cirrhotic patients were studied at baseline and 30 and 60 minutes after a standard meal and then treated with propranolol (139 +/- 9 mg/d during 39 +/- 2 days). SECOND STUDY: After baseline measurements, patients were randomized into 3 groups: (1) placebo, (2) octreotide (100 microg), or (3) octreotide (200 microg) (n = 12 for each group). Thirty minutes postinjection a new baseline was established and measurements were repeated 30 and 60 minutes after the meal. RESULTS: First study: Baseline portal pressure was 18.1 +/- 1.2 mm Hg, 30 and 60 minutes after the meal it was 21.5 +/- 0.8 mm Hg and 20.5 +/- 0.8 mm Hg, respectively (both P < 0.01 vs. baseline). Cardiac index (CI) was 4.5 +/- 0.2, 4.8 +/- 0.2, and 4.9 +/- 0.2 L x min(-1) x m(-2), respectively (both P < 0.05 vs. baseline). Peripheral vascular resistance was 1012 +/- 56, 902 +/- 51 (P = NS), and 884 +/- 49 dynes x sec x cm(-5) (P< 0.05 vs. baseline), respectively. Second study: Propranolol and placebo did not blunt postprandial increase in portal pressure. Octreotide (100 microg) partially ameliorated postprandial increase in portal pressure. Octreotide (200 microg) significantly enhanced the portal hypotensive effect of propranolol and blunted the postprandial increase in portal pressure. CONCLUSIONS: Octreotide blunts postprandial increase in portal pressure not prevented by long-term propranolol administration.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Circulação Hepática/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Octreotida/administração & dosagem , Propranolol/administração & dosagem , Vasoconstritores/administração & dosagem , Cateterismo , Quimioterapia Combinada , Feminino , Veias Hepáticas , Humanos , Masculino , Pessoa de Meia-Idade , Pressão na Veia Porta/efeitos dos fármacos , Período Pós-Prandial
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