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1.
J Viral Hepat ; 22(7): 596-606, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25412795

RESUMO

Alisporivir (ALV) is an oral, investigational host-targeting agent, with pangenotypic activity against hepatitis C virus (HCV). This randomized, double-blind, placebo-controlled, Phase II study explored the efficacy and safety of ALV with peginterferon-α2a/ribavirin (PR) in patients with chronic HCV genotype 1 infection in whom prior PR had failed (43% relapsers, 34% null responders and 23% partial responders). Four-hundred-and-fifty-nine patients were randomized (1:1:1:1) to ALV 600 mg once daily (QD), ALV 800 mg QD, ALV 400 twice daily (BID) or placebo plus PR for 48 weeks. When the global ALV trial programme was put on clinical hold, all patients in this study had received ≥31 weeks of randomized treatment; patients completed 48 weeks on PR alone. All ALV groups demonstrated superior rates of complete early virologic response (cEVR; primary endpoint) vs PR alone (P ≤ 0.0131), with highest cEVR rate seen with ALV 400 mg BID (74% vs 36% with PR alone; P < 0.0001). Respective SVR12 rates (key secondary endpoint) were 65% vs 26% in prior relapsers, 63% vs 5% in partial responders and 68% vs 3% in null responders. In patients who received >40 weeks of randomized treatment, the SVR12 rate was 89% for ALV 400 mg BID vs 30% for PR alone (P = 0.0053). Rates of viral breakthrough and relapse were lowest with ALV 400 mg BID. One case of pancreatitis (fully recovered) occurred with ALV/PR. Common AEs were headache, fatigue, anaemia, neutropenia and nausea. Hypertension was infrequent, but more common with ALV. ALV merits further investigation in interferon-free regimens in combination with direct-acting antiviral agents.


Assuntos
Antivirais/uso terapêutico , Ciclosporina/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Antivirais/efeitos adversos , Ciclosporina/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Placebos , Ribavirina/efeitos adversos , Terapia de Salvação/efeitos adversos , Terapia de Salvação/métodos , Resultado do Tratamento , Carga Viral , Adulto Jovem
2.
J Viral Hepat ; 20(8): 524-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23808990

RESUMO

Sustained virologic response (SVR) is the standard measure for evaluating response to therapy in patients with chronic hepatitis C (CHC). The aim of this study was to prospectively assess the durability of SVR in the pivotal studies of peginterferon (PEG-IFN) α-2b or IFN α-2b. We conducted two phase 3b long-term follow-up studies of patients previously treated for CHC in eight prospective randomized studies of IFN α-2b and/or PEG-IFN α-2b. Patients who achieved SVR [undetectable hepatitis C virus (HCV) RNA 24 weeks after completion of treatment] were eligible for inclusion in these follow-up studies. In total, 636 patients with SVR following treatment with IFN α-2b and 366 with SVR following treatment with PEG-IFN α-2b were enrolled. Definite relapse (quantifiable serum HCV RNA with no subsequent undetectable HCV RNA) was reported in six patients treated with IFN α-2b and three patients treated with PEG-IFN α-2b. Based on these relapses, the point estimate for the likelihood of maintaining response after 5 years was 99.2% [95% confidence interval (CI), 98.1-99.7%] for IFN α-2b and 99.4% (95% CI, 97.7-99.9%) for PEG-IFN α-2b. Successful treatment of hepatitis C with PEG-IFN α-2b or IFN α-2b leads to clinical cure of hepatitis C in the vast majority of cases.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Quimioterapia Combinada , Seguimentos , Hepacivirus/isolamento & purificação , Humanos , Interferon alfa-2 , Estudos Prospectivos , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico , Recidiva , Resultado do Tratamento
3.
Mol Psychiatry ; 17(8): 781-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21691274

RESUMO

Interferon (IFN)-α treatment for infectious diseases and cancer is associated with significant depressive symptoms that can limit therapeutic efficacy. Multiple mechanisms have been implicated in IFN-α-induced depression including immune, neuroendocrine and neurotransmitter pathways. To further explore mechanisms of IFN-α-induced depression and establish associated genetic risk factors, single nucleotide polymorphisms in genes encoding proteins previously implicated in IFN-α-induced depression were explored in two self-reported ethnic groups, Caucasians (n=800) and African Americans (n=232), participating in a clinical trial on the impact of three pegylated IFN-α treatment regimens on sustained viral response in patients with chronic hepatitis C. Before treatment, all subjects were free of psychotropic medications and had a score ≤20 on the Center for Epidemiologic Studies Depression Scale (CES-D), which was used to assess depressive symptom severity throughout the study. In Caucasians, a polymorphism (rs9657182) in the promoter region of the gene encoding indoleamine-2,3-dioxygenase (IDO1) was found to be associated with moderate or severe IFN-α-induced depressive symptoms (CES-D>20) at 12 weeks of IFN-α treatment (P=0.0012, P<0.05 corrected). Similar results were obtained for treatment weeks 24, 36 and 48. In subjects homozygous for the risk allele (CC, n=150), the odds ratio for developing moderate or severe depressive symptoms at treatment week 12 was 2.91 (confidence interval: 1.48-5.73) compared with TT homozygotes (n=270). rs9657182 did not predict depression in African Americans, who exhibited a markedly lower frequency of the risk allele at this locus. The findings in Caucasians further support the notion that IDO has an important role in cytokine-induced behavioral changes.


Assuntos
Depressão/genética , Predisposição Genética para Doença/genética , Predisposição Genética para Doença/psicologia , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Interferon-alfa/efeitos adversos , Polietilenoglicóis/efeitos adversos , Adulto , Negro ou Afro-Americano/genética , Negro ou Afro-Americano/psicologia , Alelos , Antivirais/efeitos adversos , Depressão/complicações , Depressão/psicologia , Feminino , Genótipo , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/psicologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Escalas de Graduação Psiquiátrica , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/psicologia , Proteínas Recombinantes/efeitos adversos , População Branca/genética , População Branca/psicologia
4.
J Clin Invest ; 87(2): 424-31, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1991828

RESUMO

It has been widely proposed that conversion of xanthine dehydrogenase (XDH) to its free radical-producing form, xanthine oxidase (XOD), underlies ischemic/reperfusion injury, although the relationship of this conversion to hypoxia and its physiologic control have not been defined. This study details the time course and control of this enzymatic interconversion. In a functionally intact, isolated perfused rat liver model, mean % XOD activity increased as a function of both the duration (25 to 45% in 3 h) and degree (r = 0.97) of hypoxia. This process was markedly accelerated in ischemic liver by an overnight fast (45 vs. 30% at 2 h), and by imposing a short period of in vivo ischemia (cardiopulmonary arrest 72%). Moreover, only under these conditions was there a significant rise in the XOD activity due to the conformationally altered XDH molecule (XODc, 18%), as well as concomitant morphologic injury. Neither circulating white blood cells nor thrombosis appeared to contribute to the effects of in vivo ischemia on enzyme conversion. Thus, it is apparent that conversion to the free radical-producing state, with high levels of XOD activity and concurrent cellular injury, can be achieved during a relatively short period of hypoxia under certain well-defined physiologic conditions, in a time course consistent with its purported role in modulating reperfusion injury. These data also suggest that the premorbid condition of organ donors (e.g., nutritional status and relative state of hypoxia) is important in achieving optimal organ preservation.


Assuntos
Fígado/enzimologia , Consumo de Oxigênio , Xantina Oxidase/metabolismo , Animais , Radicais Livres , Técnicas In Vitro , Fígado/fisiologia , Fígado/fisiopatologia , Neutropenia/metabolismo , Ratos , Ratos Endogâmicos , Traumatismo por Reperfusão/metabolismo , Xantina Desidrogenase/metabolismo
5.
J Clin Invest ; 94(6): 2224-30, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7989578

RESUMO

It has been widely postulated that the central mechanism of hepatic reperfusion injury involves the conversion, during ischemia, of the enzyme xanthine dehydrogenase (XDH) to its free radical-producing form, xanthine oxidase (XOD). However, this theory has been questioned because (a) XDH to XOD conversion in whole liver occurs very slowly; (b) the cellular distribution of XDH/XOD is unclear; and (c) the direct demonstration of XDH to XOD conversion in viable cells is lacking. In this paper, we address all three issues by measuring XDH to XOD conversion and cell viability in purified populations of hepatic endothelial cells (EC), Kupffer cells (KC), and hepatocytes (HEP). Although XDH/XOD activity on a cellular basis was greater in hepatocytes (0.92 +/- 0.12 mU/10(6) cells) than ECs (0.03 +/- 0.01) or KCs (0.12 +/- 0.04), XDH + XOD specific activity was similar in all three cell types (HEP 1.85 +/- 0.10 U/g protein; EC 1.69 +/- 0.54; KC 2.30 +/- 0.22). Over 150 min of warm (37 degrees C) or 24 h of cold (4 degrees C) hypoxia, percent XOD activity increased slowly in ECs, from 21 +/- 2% (basal) to 39 +/- 3% (warm) and 49 +/- 5% (cold) and in HEPs (29 +/- 2% to 38 +/- 3% and 49 +/- 2%), but converted significantly faster in KCs (28 +/- 3% to 91 +/- 7% and 94 +/- 4%). The dramatic changes in Kupffer cell XOD during cold hypoxia occurred despite only minor changes in cell viability. When hypoxic KCs were reoxygenated after 16 h of cold hypoxia, there was a marked increase in cell death that was significantly blocked by allopurinol. These data suggest that significant conversion to the free radical-producing state occurs within viable KCs, and that Kupffer cell XOD may play an important role in mediating reperfusion injury in the liver.


Assuntos
Células de Kupffer/enzimologia , Fígado/enzimologia , Xantina Desidrogenase/metabolismo , Xantina Oxidase/metabolismo , Animais , Separação Celular/métodos , Sobrevivência Celular , Temperatura Baixa , Endotélio/citologia , Endotélio/enzimologia , Temperatura Alta , Hipóxia/enzimologia , Fígado/citologia , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/etiologia , Fatores de Tempo , Distribuição Tecidual
6.
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
7.
Clin Pharmacol Ther ; 42(4): 465-70, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3311551

RESUMO

The effects of ketoconazole and methylprednisolone on endogenous cortisol were studied in eight normal subjects. Intravenous methylprednisolone sodium succinate was given alone in doses of 15 or 30 mg. The methylprednisolone dose was reduced by 57% when ketoconazole was administered chronically for 1 week to seek equivalent methylprednisolone AUCs by compensating for the expected reduction in methylprednisolone clearance. Ketoconazole decreased clearance by 46% and increased mean residence time by 37%. The ratio of the cortisol AUC during each drug treatment compared with baseline conditions was used to assess the net extent and duration of cortisol suppression. This cortisol AUC ratio was reduced from 0.45 (methylprednisolone) to 0.39 (methylprednisolone plus ketoconazole), suggesting that ketoconazole modestly enhanced (P less than 0.01) cortisol suppression. Based on the reduction in methylprednisolone clearance and cortisol AUC by ketoconazole, a 50% lower dose of methylprednisolone during concomitant therapy with ketoconazole is recommended.


Assuntos
Hidrocortisona/metabolismo , Cetoconazol/farmacologia , Hemissuccinato de Metilprednisolona/farmacocinética , Metilprednisolona/análogos & derivados , Adulto , Análise de Variância , Ensaios Clínicos como Assunto , Humanos , Hidrocortisona/sangue , Cetoconazol/administração & dosagem , Masculino , Hemissuccinato de Metilprednisolona/administração & dosagem , Hemissuccinato de Metilprednisolona/sangue , Distribuição Aleatória , Fatores de Tempo
8.
Clin Pharmacol Ther ; 39(6): 654-9, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3709030

RESUMO

The disposition of methylprednisolone was examined in six normal subjects after the injection of 20 mg iv methylprednisolone sodium succinate. Disposition studies were performed both without and with ketoconazole, 200 mg/day, for 6 days. Ketoconazole increased the methylprednisolone AUC and mean residence time (by 135% and 66%, respectively) and decreased clearance (60%), the terminal phase slope, and the volume of distribution. These findings are typical of macrolide antibiotic alteration of methylprednisolone disposition and consistent with reports of inhibition of drug metabolism by ketoconazole. Methylprednisolone reduced the 24-hour cortisol AUC by 44%, but morning cortisol concentrations returned to normal. Ketoconazole with methylprednisolone further reduced the 24-hour cortisol AUC and suppressed morning cortisol concentrations. Thus ketoconazole inhibits methylprednisolone disposition and extends the adrenal suppression effects of this corticosteroid.


Assuntos
Hidrocortisona/metabolismo , Cetoconazol/farmacologia , Metilprednisolona/metabolismo , Adulto , Análise de Variância , Interações Medicamentosas , Humanos , Hidrocortisona/sangue , Injeções Intravenosas , Cinética , Masculino , Metilprednisolona/sangue , Distribuição Aleatória
9.
Transplantation ; 58(12): 1329-35, 1994 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-7809924

RESUMO

Despite general agreement on the importance of oxyradicals in mediating "reperfusion" injury, the precise event(s) mediated by increased free radical production remain unclear. In this study we describe for the first time a model of unenhanced chemiluminescence of isolated perfused rat liver demonstrating a marked increase in oxyradical production after reoxygenation. Using aspartate aminotransferase and purine nucleoside phosphorylase release as measures of liver injury, there was no direct link between oxyradical production and hepatic injury. However, there was an abrupt increase in neutrophil chemotaxis activity in the perfusate at the time of reoxygenation with a subsequent decrement, following the pattern of oxyradical production. These data suggest that free radical formation during hepatic reperfusion may mediate signal transduction, as opposed to direct cell injury, as a primary mechanism of action.


Assuntos
Fígado/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Radicais Livres/metabolismo , Fígado/patologia , Fígado/fisiologia , Medições Luminescentes , Masculino , Oxirredução , Perfusão , Purina-Núcleosídeo Fosforilase/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
10.
J Clin Psychiatry ; 50(2): 57-9, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2914881

RESUMO

Thirty patients meeting DSM-III-R criteria for bulimia nervosa with at least three bingeing episodes a week were compared with 30 age- and sex-matched controls on DSM-III personality measures. The bulimic patients were more likely to display cluster B (histrionic, narcissistic, antisocial, and borderline) personality abnormalities (odds ratio 15.0) and cluster C (avoidant, dependent, compulsive, and passive-aggressive) personality abnormalities (odds ratio 4.3) than were the community controls. This study supports the finding that personality disorder is a possible risk factor for bulimia.


Assuntos
Bulimia/complicações , Transtornos da Personalidade/complicações , Transtorno da Personalidade Borderline/complicações , Transtorno da Personalidade Borderline/psicologia , Bulimia/psicologia , Transtorno Depressivo/complicações , Transtorno Depressivo/psicologia , Feminino , Humanos , Transtornos da Personalidade/psicologia , Escalas de Graduação Psiquiátrica , Fatores de Risco
11.
Clin Ther ; 20(3): 388-97, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9663356

RESUMO

Results of numerous studies have demonstrated similar efficacy profiles for the interferons (IFNs) currently approved for the treatment of chronic hepatitis C virus (HCV) infection. Although it has been suggested that some IFNs are more efficacious in certain patient populations, the current data support an equivalent efficacy and safety profile for these agents. Among patients requiring retreatment, no single study has made a direct comparison of IFN alfa-2b (IFN-alpha 2b) and consensus IFN (CIFN) in patients who have relapsed or have not responded to previous IFN therapy. However, at least 11 studies using IFN-alpha 2b and 1 using CIFN have demonstrated efficacy in the relapsing and nonresponding patient populations. A review of these studies suggests that overall efficacy and tolerability are similar regardless of IFN-alpha subtype. Overall, up to 59% and 83% of relapsed patients retreated with IFN have shown sustained response rates, as measured by negative HCV RNA titer and normalization of alanine aminotransferase (ALT) levels, respectively. Up to 14% and 25% of patients who failed to respond to previous IFN therapy have shown sustained HCV RNA response and normalization of ALT, respectively, after retreatment.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , Animais , Humanos , Recidiva
12.
Brain Res ; 223(1): 229-34, 1981 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-7284807

RESUMO

Female Fischer and Sprague-Dawley rats rotate significantly more in response to D-amphetamine sulfate (1 mg/kg, i.p.) than their male littermates. Although Sprague-Dawley males rotate more than females when injected with apomorphine hydrochloride (10 mg/kg, i.p.), Fischer males and females respond similarly to this drug. The sexually dimorphic behavioral response to amphetamine appears to be due to differences in brain sensitivity to this drug, and may relate to reports of sex-related differences in nigrostriatal dopaminergic activity.


Assuntos
Dextroanfetamina/farmacologia , Atividade Motora/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Ratos , Ratos Endogâmicos , Rotação , Fatores Sexuais , Especificidade da Espécie
13.
Am J Surg ; 135(1): 91-6, 1978 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-341733

RESUMO

A prospective randomized clinical trial assessing the relative effectiveness of erythromycin-neomycin and metronidazole-neomycin as a preoperative bowel preparation was carried out. Bacteriologic studies of feces and colon content revealed no significant difference in the reduction of aerobic bacteria between the two groups. There was, however, a significantly greater reduction in anaerobic bacteria in the feces and colon contents of patients receiving metronidazole. Wound infection rate was 25% in the erythromycin group, and organisms recovered from the wound in all cases were fecal in nature. Two wound infections occurred in the metronidazole group (5%) and in both cases the organisms recovered were staphylococci of presumed skin origin. These studies suggest that anaerobic bacteria are the major contributors to wound infection after colon surgery and that their specific reduction is associated with a lower incidence of wound infection.


Assuntos
Colo/cirurgia , Metronidazol/uso terapêutico , Infecção da Ferida Cirúrgica/prevenção & controle , Bacteroides/efeitos dos fármacos , Ensaios Clínicos como Assunto , Colo/microbiologia , Eritromicina/uso terapêutico , Fezes/microbiologia , Bactérias Anaeróbias Gram-Negativas/efeitos dos fármacos , Humanos , Metronidazol/farmacologia , Neomicina/uso terapêutico , Infecção da Ferida Cirúrgica/microbiologia
14.
J Pharm Sci ; 75(5): 443-7, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-3735080

RESUMO

The single-dose pharmacokinetics and bioavailability of three ketoconazole formulations were evaluated using HPLC in five healthy human volunteers and six male mongrel dogs. The human volunteers received 400 mg po of ketoconazole as tablet (Ktab) and solution (Ksol) formulations. The dogs received 400 mg po of Ktab and Ksol, and 376 mg iv of an intravenous dose (Kiv). In humans the AUC value for Ksol (62.21 +/- 21.2 microgram X h/ml; mean +/- SD) was significantly greater than for Ktab (50.0 +/- 15.2 micrograms X h/ml; p less than 0.05). Peak serum concentrations (Cmax), time to peak serum concentrations (tmax), t1/2, and the terminal elimination rate constant (kel) did not differ between Ktab and Ksol. This suggests that the administration of Ksol may be a useful alternative to dosage increases in situations where low bioavailability of ketoconazole in tablet form is suspected. The mean systemic clearance (CLs) of Kiv in dogs was 2.74 +/- 1.10 mL/min/kg, the volume of distribution at steady state (Vdss) was 0.72 +/- 0.28 L/kg, and the half-life was 2.7 +/- 1.6 h. Considerable variability was seen in the AUC of ketoconazole, particularly with the oral preparations. The absolute bioavailability of Ktab was 0.50 +/- 0.38, which did not differ statistically from that of Ksol, 0.56 +/- 0.23. The Ksol showed less variability in AUC, Cmax, and F values than did Ktab, and two dogs with low bioavailability with Ktab (0.04 and 0.07) had substantially greater bioavailability with Ksol (F = 0.96 and 0.57, respectively). Evaluation of Kiv in dogs confirms decreased bioavailability from orally administered tablet formulations of ketoconazole.


Assuntos
Cetoconazol/metabolismo , Administração Oral , Adulto , Animais , Disponibilidade Biológica , Cães , Humanos , Injeções Intravenosas , Cetoconazol/administração & dosagem , Cinética , Masculino , Soluções , Especificidade da Espécie , Comprimidos
15.
Aliment Pharmacol Ther ; 38(1): 16-27, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23710734

RESUMO

BACKGROUND: Adherence to therapeutic regimens affects the efficacy of peginterferon alfa (P) and ribavirin (R) therapy in patients with chronic hepatitis C virus genotype 1. AIM: To determine if medication adherence impacts efficacy [sustained virological response (SVR)] with triple therapy that includes boceprevir (BOC) plus P/R. METHODS: Adherence was determined in two Phase 3 clinical studies with BOC: SPRINT-2 (previously untreated patients) and RESPOND-2 (patients who failed previous therapy with P/R). Adherence to the assigned duration of the dosing regimen and adherence to the three times a day (t.d.s.) dosing interval of 7-9 h for BOC were assessed by the recording of data from patients' dosing diaries and by the amount of study drug dispensed and returned. RESULTS: Most patients (63-71%) adhered to ≥80% of their assigned treatment duration and achieved SVR rates of 86-90%. In contrast, patients who adhered to <80% of their assigned treatment duration achieved SVR rates of 8-32% (P < 0.0001), particularly low in patients who failed previous therapy (SVR = 8-15%). Different rates of adherence (<60% to >80%) to the t.d.s. dosing interval (7-9 h) with BOC did not influence the SVR rates (SVR = 60-83%) with the exception of patients who failed previous treatment and adhered to <60% of the t.d.s. dosing interval with BOC (SVR = 48-50%; P = 0.005). CONCLUSIONS: The achievement of an SVR is more dependent on adherence to the assigned duration of treatment than adherence to the t.d.s. dosing interval with boceprevir. Adherence to >60% of t.d.s. dosing with boceprevir is important in patients who failed previous therapy.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adesão à Medicação , Polietilenoglicóis/uso terapêutico , Prolina/análogos & derivados , Ribavirina/uso terapêutico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Genótipo , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Prolina/uso terapêutico , RNA Viral/genética , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Carga Viral
19.
Hepatology ; 21(1): 174-9, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7806152

RESUMO

With emerging data that endothelial cell (EC) injury is the limiting factor in liver preservation and hepatic function, a simple and reliable biochemical technique for monitoring EC injury is needed. Measurement of purine nucleoside phosphorylase (PNP) release into the circulation from perfused liver has been proposed as such a method. However, our experiments with perfused rat liver did not display a clear or direct relationship between PNP release and endothelial cell injury. Therefore, we re-examined the suitability of using PNP as a measure of nonparenchymal injury by measuring its distribution in purified populations of hepatocytes, ECs, and Kupffer cells (KCs) and correlating cell injury and enzyme release in short-term cultures at 37 degrees C of each cell type. Purified cells were incubated (4 x 10(6) cells/mL) in oxygen or nitrogen saturated. Wisconsin solution or Krebs buffer for 6 hours, with cell viability and PNP release assayed every 2 hours. ECs had the lowest specific activity (27 +/- 9 U/mg protein; mean +/- standard error of the mean [SEM]) compared with both hepatocytes (115 +/- 15) and KCs (66 +/- 18). Despite a decrement in EC and KC viability over time in each incubation solution, there was poor correlation between time of incubation and PNP release (r = .01 to .22), and between cell viability and PNP release (r = .01 to .16). In contrast, PNP release from incubated hepatocytes correlated with the length of incubation (r = .57 to .78) as well as cell injury (r = .63 to .77) in all four test solutions.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fígado/patologia , Soluções para Preservação de Órgãos , Purina-Núcleosídeo Fosforilase/metabolismo , Adenosina/farmacologia , Alopurinol/farmacologia , Animais , Soluções Tampão , Separação Celular , Endotélio/metabolismo , Endotélio/patologia , Glutationa/farmacologia , Insulina/farmacologia , Soluções Isotônicas/farmacologia , Células de Kupffer/metabolismo , Fígado/efeitos dos fármacos , Masculino , Rafinose/farmacologia , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
20.
Gastroenterology ; 108(4): 1167-75, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7698585

RESUMO

BACKGROUND/AIMS: Free radicals are important mediators of reperfusion injury; however, the mechanism(s) of oxyradical production after liver reimplantation are not well understood. A model of cold storage and reperfusion using low-level chemiluminescence to directly measure oxyradical production during reperfusion was developed. METHODS: Rat livers were harvested and stored at 4 degrees C in University of Wisconsin cold-storage solution or Euro-Collins solution for 0-48 hours and then flushed and reperfused with warm oxygenated (37 degrees C) Krebs-Henseleit buffer. Liver chemiluminescence was measured using a sensitive photomultiplier tube, and hepatocellular injury was assessed by measuring aspartate aminotransferase release into the perfusate. RESULTS: Chemiluminescence reached a maximum within 5 minutes of reperfusion and then decreased to a baseline within 30 minutes. There was a marked increase in chemiluminescence after only a short period of storage in University of Wisconsin cold-storage solution. Chemiluminescence decreased with longer periods of storage but steadily increased again after 16 hours of storage. Chemiluminescence after 22 hours of storage, but not after 3 hours of storage, was decreased by pretreatment with the Kupffer cell inactivator gadolinium chloride. CONCLUSIONS: The data suggest two mechanisms of oxyradical production during cold storage and reperfusion of the rat liver. The later phase seems to be Kupffer cell dependent.


Assuntos
Células de Kupffer/metabolismo , Fígado/metabolismo , Soluções para Preservação de Órgãos , Preservação de Órgãos/métodos , Oxigênio/metabolismo , Adenosina , Alopurinol , Animais , Aspartato Aminotransferases/metabolismo , Temperatura Baixa , Radicais Livres , Glutationa , Soluções Hipertônicas , Insulina , Análise dos Mínimos Quadrados , Fígado/enzimologia , Medições Luminescentes , Masculino , Rafinose , Ratos , Ratos Sprague-Dawley , Reperfusão , Traumatismo por Reperfusão/metabolismo
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