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1.
Anaesthesia ; 78(7): 861-873, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36632667

RESUMO

Kidney disease, both acute and chronic, is commonly encountered on the intensive care unit. Due to the role the kidneys play in whole body homeostasis, it follows that their dysfunction has wide-ranging implications and can affect prescribing and therapeutic management. This narrative review discusses the pathophysiology of acute kidney injury and chronic kidney disease, and how this relates to critically unwell patients. We cover several aspects of the management of renal dysfunction on the critical care unit, exploring some of the recurrent themes within the literature, including type and timing of kidney replacement therapy, management of acute kidney injury, as well as discussing how novel biomarkers for acute kidney injury may help to identify patients suffering from acute kidney injury as well as risk stratifying these patients. We discuss how early involvement of specialist nephrology services can improve outcomes in patients with kidney disease as well as offer valuable diagnostic and specialist management advice, particularly for patients with established end stage kidney disease and patients who are already known to nephrology services. We also explore some of the ongoing research questions that need to be answered within this arena.


Assuntos
Injúria Renal Aguda , Falência Renal Crônica , Nefrologia , Insuficiência Renal Crônica , Humanos , Unidades de Terapia Intensiva , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/terapia , Terapia de Substituição Renal , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/terapia , Injúria Renal Aguda/etiologia , Estado Terminal/terapia
2.
J Acoust Soc Am ; 148(4): EL307, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33138473

RESUMO

To explore how crocodilians locate a sound source, two Nile crocodiles (Crocodylus niloticus) were trained to swim towards an acoustic target. Using filtered versions of synthesized stimuli, the respective roles of interaural level differences (ILDs) and interaural time differences (ITDs), which are the two main cues providing information on sound source position, were tested. This study shows that crocodiles rely on both ILDs and ITDs to locate the spatial direction of a sound source and that their performance is lower when one of the cues is lacking.


Assuntos
Jacarés e Crocodilos/fisiologia , Localização de Som , Estimulação Acústica , Animais , Sinais (Psicologia)
3.
J Viral Hepat ; 23(11): 905-911, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27375231

RESUMO

Quantitative hepatitis B core-related antigen (qHBcrAg) has been proposed as an additional marker to quantitative HBsAg (qHBsAg), for management of chronic hepatitis B. Evaluate baseline combination of qHBsAg and qHBcrAg for identification of patients that could benefit from pegylated interferon-alpha-2a (PegIFN)-based therapy. Sixty-two HBeAg-negative patients treated with PegIFN or PegIFN plus tenofovir disoproxil fumarate (PegIFN+TDF). HBsAg and HBcrAg titres were evaluated at baseline. Thirty patients received PegIFN and 32 PegIFN+TDF. SR was 10 of 30 and 17 of 32 in PegIFN and PegIFN+TDF patients, respectively. Cut-offs determined by maximized Youden's index for identifying patients likely to respond to therapy were as follows: 3.141 log10 IU/mL and 3.450 log10 U/mL for HBsAg and HBcrAg, respectively. At the end of 3 years post-treatment follow-up, HBsAg loss was observed in 7 of 30 and 6 of 32 in PegIFN and PegIFN+TDF patients, respectively. The AUC was estimated to be 0.716 (95% CI [0.578, 0.855]) for HBsAg and 0.668 (95% CI [0.524, 0.811]) for HBcrAg (P=.5541). PPVs for AUCs(95%CI) were 0.762(0.590-0.947), 0.714(0.533-1.000) and 0.800(0.611-1.000), and NPVs for AUCs(95%CI) were 0.756(0.660-0.899), 0.718(0.630-0.857) and 0.765(0.675-0.889) for qHBsAg, qHBcrAg and the combination of both markers, respectively. Baseline qHBsAg 3.141 log10 IU/mL and qHBcrAg 3.450 log10 U/mL thresholds used separately or in combination allow prediction of response, prior to PegIFN-based therapy, with a PPV of 80.3% and NPV of 76.5%. Baseline qHBsAg is predictive of HBsAg loss. Both markers could be used, separately or in combination, for PegIFN-based 'precision therapy'. Our results emphasize that the combination of PegIFN alpha-2a plus TDF with 53% of SR might be an alternative to finite therapy.


Assuntos
Antivirais/uso terapêutico , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Medicina de Precisão/métodos , Adulto , Feminino , Hepatite B Crônica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Resposta Viral Sustentada , Tenofovir/uso terapêutico , Resultado do Tratamento
4.
J Viral Hepat ; 21(7): 525-32, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24118626

RESUMO

UNLABELLED: The impact of IFNL3 (IL28B) polymorphism on response to interferon (IFN) treatment in patients infected with hepatitis B virus (HBV) is controversial. We aimed to investigate whether IFNL3 polymorphism (rs12979860) influences the long-term response of chronic hepatitis B (CHB) treatment to conventional IFN. DESIGN: Ninety-seven HBeAg-positive patients treated with IFN were evaluated in this study. Associations were investigated between IFNL3 genotypes and (i) HBeAg seroconversion at the end of treatment (EOT), (ii) sustained virological response (SVR) and (iii) HBsAg seroconversion through long-term follow-up (LTFU). Patients were followed for a median of 14 years. The majority of patients were infected with HBV genotype A (69.6%) and were Caucasian (77.9%). Ninety-five patients were genotyped at rs12979860. Similar IFNL3 distribution was observed among the different ethnicities (P = 0.62) or across HBV genotypes A through G (P = 0.70). Thirty-six patients experienced HBeAg seroconversion at EOT; HBeAg seroconversion rates were 37.0 and 35.5% in patients with CC and CT/TT genotypes, respectively (P = 0.82). Among the 44 patients (45%) who achieved a SVR, SVR rates were 48.9 and 39.6% in patients with CC and CT/TT IL28B genotypes, respectively (P = 0.80). HBsAg seroconversion occurred through LTFU in 28 patients. HBsAg seroconversion rates were 25.5 and 31.2% in patients with CC and CT/TT genotypes, respectively (P = 0.51). No significant relationship between IFNL3 rs12979860 and fibrosis stage was observed (P = 0.85). IFNL3 genotype was neither associated with SVR, nor with HBeAg seroconversion and long-term HBsAg seroconversion in HBeAg-positive CHB patients responding to IFN therapy.


Assuntos
Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Prognóstico , Adulto , Idoso , DNA Viral/sangue , Feminino , Seguimentos , Genótipo , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Interferons , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Viral , Adulto Jovem
5.
J Viral Hepat ; 18(8): 580-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20487260

RESUMO

To assess the impact of sequential therapy with adefovir dipivoxil (ADV) and pegylated interferon alfa-2a (PEG-IFN) on virological (serum HBV-DNA) and serological (serum HBsAg) response in 20 consecutive HBeAg-negative patients. Patients received ADV for 20 weeks, then ADV and PEG-IFN for 4 weeks and lastly PEG-IFN for 44 weeks. Serum HBV-DNA and HBsAg were assessed at baseline, during therapy (weeks 20, 44 and 68) and follow-up (weeks 92 and 116). Sustained virological response (SVR) was defined as serum HBV-DNA <10 000 copies/mL (partial) or <70 copies/mL (complete) 24 weeks after stopping treatment. A serological response was defined as a serum HBsAg decrease ≥1 log(10) IU/mL at the end of treatment. Baseline median serum HBV-DNA and HBsAg levels were 7.6 log(10) copies/mL and 3.8 log(10) IU/mL, respectively. Ten patients (50%) achieved SVR, six of them had partial response and four complete response. Four patients (20%) achieved serological response. Complete SVRs showed a major and steep decline in HBsAg level with a median decrease of 0.5, 1.6 and 2.0 log(10) IU/mL at treatment week 20, 44 and 68, respectively. Partial SVRs showed a slight and slow decline in serum HBsAg level (0.1, 0.4, and 0.6 log IU/mL at weeks 20, 44 and 68, respectively). On-treatment serum HBsAg decrease had a high accuracy to predict SVR (AUROC = 0.88). Our results suggest that sequential therapy might be an interesting strategy for HBeAg-negative patients. Serum HBsAg kinetics seem to be an accurate tool to predict SVR. Large clinical trials are needed to explore this strategy with more potent analogues.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Organofosfonatos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adenina/administração & dosagem , Adenina/uso terapêutico , Adulto , Alanina Transaminase/sangue , Antivirais/administração & dosagem , DNA Viral/sangue , DNA Viral/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Genótipo , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/efeitos dos fármacos , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Organofosfonatos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Proteínas Recombinantes
6.
Gut ; 58(12): 1662-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19671541

RESUMO

BACKGROUND AND AIMS: Hepatitis C virus (HCV) genotype 4 (HCV-4) is increasing in prevalence in Western countries. However, little is known about the severity of the disease and response to treatment. The aim of this study was to assess the predictors (logistic regression) of severe fibrosis (METAVIR score F3-F4), and sustained virological response (SVR) to peginterferon and ribavirin in 226 consecutive HCV-4 patients (Egyptians 40%, Europeans 35% and Africans 24%). PATIENTS AND METHODS: Insulin resistance was assessed using the homeostasis model (HOMA-IR). Serum HCV-RNA level (bDNA) and subtypes of HCV (LiPA) were determined for all patients. RESULTS: Insulin resistance (HOMA-IR >3) was present in 105 patients (46%), and was associated with: age >45 years (OR, 2.614; 95% CI, 1.316 to 5.194), body mass index (BMI) >25 kg/m(2) (OR, 2.105; 95% CI, 1.048 to 4.229), serum HCV-RNA >800 000 IU/ml (OR, 3.143; 95% CI, 1.503 to 6.574), severe fibrosis (OR, 2.657; 95% CI, 1.214 to 5.818), and steatosis >30% (OR, 2.488; 95% CI, 1.105 to 5.602). Severe fibrosis was present in 67 patients (29%) and was associated with Egyptian origin (OR, 5.872; 95% CI, 2.747 to 12.553), excessive alcohol intake (OR, 5.311; 95% CI, 1.287 to 21.924), and HOMA-IR >3 (OR, 3.864; 95% CI, 1.859 to 8.034). 108 patients received a 48 week course of peginterferon plus ribavirin. SVR (undetectable serum HCV-RNA (TMA) 24 weeks after treatment stopping) was achieved in 59 patients (55%) and was associated with Egyptian origin (OR, 13.119; 95% CI, 3.089 to 55.706), HOMA-IR <2 (OR, 5.314; 95% CI, 1.953 to 14.459), and non-severe fibrosis (OR, 8.059; 95% CI, 2.512 to 25.855). CONCLUSION: Insulin resistance and geographical origin are major predictors of liver fibrosis and response to peginterferon and ribavirin in HCV-4 patients. Insulin resistance is frequently encountered in these patients, and correlated independently with serum HCV-RNA.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/complicações , Resistência à Insulina/etnologia , Cirrose Hepática/virologia , Adulto , População Negra/estatística & dados numéricos , Egito/etnologia , Feminino , França/epidemiologia , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/etnologia , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Cirrose Hepática/etnologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Estudos Prospectivos , RNA Viral/sangue , Proteínas Recombinantes , Ribavirina/uso terapêutico , Resultado do Tratamento
7.
Gut ; 57(4): 516-24, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17895355

RESUMO

BACKGROUND AND AIMS: The gold standard treatment of chronic hepatitis C (CHC) is combined pegylated interferon and ribavirin. Considering side effects and treatment cost, prediction of treatment response before therapy is important. The aim of this study was to identify a liver gene signature to predict sustained virological response in patients with CHC. METHODS: Group A (training set) comprised 40 patients with CHC including 14 non-responders (NRs) and 26 sustained virological responders (SVRs). Group B (validation set) comprised 29 patients including 9 NRs and 20 SVRs. Eleven responder-relapsers were also included. A total of 58 genes associated with liver gene expression dysregulation during CHC were selected from the literature. Real-time quantitative RT-PCR assays were used to analyse the mRNA expression of these 58 selected genes in liver biopsy specimens taken from the patients before treatment. RESULTS: From the Group A data, three genes whose expression was significantly increased in NRs compared with SVRs were identified: IFI-6-16/G1P3, IFI27 and ISG15/G1P2. These three genes also showed significant differences in their expression profiles between NRs and SVRs in the independent sample (Group B). Supervised class prediction analysis identified a two-gene (IFI27 and CXCL9) signature, which accurately predicted treatment response in 79.3% (23/29) of patients from the validation set (Group B), with a predictive accuracy of 100% (9/9) and of 70% (14/20) in NRs and SVRs, respectively. The expression profiles of responder-relapsers did not differ significantly from those of NRs and SVRs, and 73% (8/11) of them were predicted as SVRs with the two-gene classifier. CONCLUSION: NRs and SVRs have different liver gene expression profiles before treatment. The most notable changes occurred mainly in interferon-stimulated genes. Treatment response could be predicted with a two-gene signature (IFI27 and CXCL9).


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Estudos de Coortes , Quimioterapia Combinada , Feminino , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Marcadores Genéticos , Hepatite C Crônica/metabolismo , Humanos , Interferon alfa-2 , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , Prognóstico , RNA Mensageiro/genética , Proteínas Recombinantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Resultado do Tratamento
8.
R Soc Open Sci ; 6(7): 190423, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31417740

RESUMO

As top predators, crocodilians have an acute sense of hearing that is useful for their social life and for probing their environment in hunting situations. Although previous studies suggest that crocodilians are able to localize the position of a sound source, how they do this remains largely unknown. In this study, we measured the potential monaural sound localization cues (head-related transfer functions; HRTFs) on alive animals and skulls in two situations, both mimicking natural positions: basking on the land and cruising at the interface between air and water. Binaural cues were also estimated by measuring the interaural level differences (ILDs) and the interaural time differences (ITDs). In both conditions, HRTF measurements show large spectral variations (greater than 10 dB) for high frequencies, depending on the azimuthal angle. These localization cues are influenced by head size and by the internal coupling of the ears. ITDs give reliable information regarding sound-source position for low frequencies, while ILDs are more suitable for frequencies higher than 1.5 kHz. Our results support the hypothesis that crocodilian head morphology is adapted to acquire reliable localization cues from sound sources when outside the water, but also when only a small part of their head is above the air-water interface.

9.
Gastroenterol Clin Biol ; 32(8-9): 749-68, 2008.
Artigo em Francês | MEDLINE | ID: mdl-18775613

RESUMO

SUMMARY: In recent years, marked progress has been made in the treatment of chronic hepatitis B. Several agents have been approved: interferon alpha-(IFN), pegylated interferon alpha2a (PEG-IFN alpha2a), lamivudine, adefovir, entecavir, telbivudine and recently, tenofovir. Each drug has advantages and limitations. IFN and PEG-IFN alpha2a have the advantage of inducing a sustained virologic response after a defined, limited course of treatment. However, these drugs are only effective in a minority of patients and have frequent side effects. Analogues have the advantage of being administered orally, with good safety profiles and a potent antiviral effect. However, these drugs need to be administered indefinitely since withdrawal of therapy is generally associated with reactivation, and a sustained response is uncommon except in HBeAg positive patients who develop HBe seroconversion. In case of HBe seroconversion, therapy should usually be continued for at least another 24 weeks. The efficacy of lamivudine is limited by the emergence of lamivudine-resistant HBV. Adefovir is associated with a moderate incidence of resistance but its antiviral effect is not optimal. Entecavir has shown to be more effective with a favourable safety profile and a low incidence of resistance. Telbivudine is more potent and has a lower rate of resistance than lamivudine but the resistance rate is significantly higher than other approved drugs. Tenofovir has a potent antiviral effect with a good resistance profile. The future of chronic hepatitis B therapy appears to be different drug combinations. Normally the advantage of drug combinations versus monotherapy should be additive or synergistic antiviral effects and a decrease in viral resistance. Unfortunately, there are few data available and none of the evaluated analogue combinations have been shown to be better than monotherapy. The only combination which has shown a synergistic effect is of pegylated interferon alpha2a with lamivudine. Therefore, combinations of pegylated interferon with the most potent analogues need to be evaluated. The ultimate goal of therapy is HBsAg seroconversion which is more often observed with interferon. Indeed, quantification of serum HBsAg will be a useful tool to predict the treatment outcome. More potent drugs and new combinations as well as understanding the mechanisms of viral resistance should be evaluated to improve the efficacy of treatment.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Antivirais/uso terapêutico , Farmacorresistência Viral , Quimioterapia Combinada , Humanos , Interferons/uso terapêutico
10.
Minerva Gastroenterol Dietol ; 53(1): 9-23, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17415342

RESUMO

Chronic hepatitis C is a major cause of cirrhosis and primary liver cancer (hepatocellular carcinoma). Decompensated cirrhosis or hepatocellular carcinoma secondary to hepatitis C is the first cause of liver transplantation in Europe and in the United States. The prognosis of chronic hepatitis C depends on the progression of fibrosis which determines the risk of developing cirrhosis and its complications. Knowledge of the natural history and the factors associated with the progression of fibrosis is essential for the patient's management. The risk of the progression of fibrosis is difficult to predict in one particular patient. Liver biopsy remains the best test to evaluate the severity of fibrosis, determine its prognosis and discuss the therapeutic options. At present, in a patient with hepatitis C, combined therapy associating pegylated alpha interferon and ribavirin results in a sustained response in approximately 55% of cases. Based on existing results, the sustained virological response with this treatment option appears to be long lasting, to be associated with a histological benefit and is also probably associated with a reduction in the risk of cirrhosis and hepatocellular carcinoma. The management of hepatitis C virus infections must include better knowledge of the natural history of the disease and existing available antiviral treatments (pegylated interferon and ribavirin) as well as in depth knowledge of the aims of treatment, the results obtained, the predictive factors of response and side effects. With close follow-up, doses can be rapidly modified and erythropoietin more frequently administered; new molecules may also be developed in this context. This paper will discuss the natural history, the factors associated with the progression of fibrosis, the predictive factors of response to treatment, and existing and future treatments for hepatitis C.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Árvores de Decisões , Progressão da Doença , Hepatite C Crônica/complicações , Hepatite C Crônica/genética , Humanos , Interferons/uso terapêutico , Cirrose Hepática/etiologia , Ribavirina/uso terapêutico
11.
Minerva Gastroenterol Dietol ; 52(1): 23-38, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16554704

RESUMO

Five agents are currently approved for the treatment of chronic hepatitis B: standard interferon-alpha (IFN-alpha), pegylated interferon-alpha 2a (PEG-IFN-alpha 2a), lamivudine, adefovir and entecavir. Each agent has inherent limitations. IFN and PEG-IFN-alpha 2a are effective in a minority of patients and have frequent side effects that limit their tolerability. The efficacy of lamivudine is limited by the emergence of drug-resistant hepatitis B virus (HBV) mutants, restricting its utility as a long-term therapy. Adefovir is well tolerated and associated with a low incidence of resistance but its antiviral effect is not optimal. Entecavir, which has been recently registered, has a more potent anti-viral effect but its long term efficacy and resistance profile is still not known. These antivirals induce a sustained response after withdrawal of therapy in only a minority of patients and therefore the treatment needs to be indefinitely administered in the majority of patients. After a brief summary of the natural history of chronic hepatitis B in order to understand the indications and the objectives of therapy, this review focuses on treatment of HBeAg-negative chronic hepatitis B with IFN and PEG-IFN-alpha 2a.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Adenina/análogos & derivados , Adenina/uso terapêutico , Guanina/análogos & derivados , Guanina/uso terapêutico , Antígenos E da Hepatite B , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Lamivudina/uso terapêutico , Organofosfonatos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes
12.
Biochim Biophys Acta ; 1235(2): 249-55, 1995 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-7756332

RESUMO

Fluidity changes in plasma membrane (PM) lipid extracts or native membranes isolated from Bryonia dioica internodes after a mechanical stimulation were monitored by steady-state fluorescence polarization with 1,6-diphenyl-1,3,5-hexatriene as a probe. The signal was shown to rapidly induce an increase in the bulk lipid fluidity. This event was closely related to a relative enrichment in some phospholipid species (PC, PG and PS) as well as a significant increase in the unsaturation index of total fatty acyl chains. Free sterols and protein content did not appear to be involved into this process. After 48 h, lipids from rubbed internodes became less fluid than PM lipids from control internodes.


Assuntos
Fluidez de Membrana/fisiologia , Lipídeos de Membrana/fisiologia , Plantas/ultraestrutura , Membrana Celular/química , Membrana Celular/fisiologia , Difenilexatrieno , Ácidos Graxos/análise , Polarização de Fluorescência , Lipídeos de Membrana/análise , Morfogênese , Fosfolipídeos/análise , Estimulação Física , Fenômenos Fisiológicos Vegetais , Esteróis/análise
13.
Minerva Gastroenterol Dietol ; 51(1): 63-75, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15756147

RESUMO

The natural course of hepatitis B virus (HBV) chronic infection is variable, ranging from an inactive HBsAg carrier state to a more or less progressive chronic hepatitis, potentially evolving to cirrhosis and hepatocellular carcinoma (HCC). Chronic hepatitis may present as typical HBeAg-positive chronic hepatitis B or HBeAg-negative chronic hepatitis B. HBeAg-positive chronic hepatitis is due to wild type HBV; it represents the early phase of chronic HBV infection. HBeAg-negative chronic hepatitis is due to a naturally occurring HBV variant with mutations in the precore or/and basic core promoter regions of the genome; it represents a late phase of chronic HBV infection. The latter form of the disease has been recognized as increasing in many countries within the last decade and it represents the majority of cases in many countries. HBeAg-negative chronic hepatitis B is generally associated with a more severe liver disease with a very low rate of spontaneous disease remission and a low sustained response rate to antiviral therapy. Longitudinal studies of patients with chronic hepatitis B indicate that, after diagnosis, the 5-year cumulative incidence of developing cirrhosis ranges from 8-20%. Morbidity and mortality in chronic hepatitis B are linked to evolution to cirrhosis or HCC. The 5-year cumulative incidence of hepatic decompensation is approximately 20%. The 5-year probability of survival is approximately 80-86% in patients with compensated cirrhosis. Patients with decompensated cirrhosis have a poor prognosis (14-35% probability of survival at 5 years). HBV-related end-stage liver disease or HCC are responsible for at least 500,000 deaths per year.


Assuntos
Hepatite B , Adolescente , Adulto , Carcinoma Hepatocelular/etiologia , Criança , Diagnóstico Diferencial , Progressão da Doença , Hepatite B/complicações , Hepatite B/diagnóstico , Hepatite B/tratamento farmacológico , Hepatite B/epidemiologia , Hepatite B/imunologia , Hepatite B/virologia , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/mortalidade , Hepatite B Crônica/virologia , Humanos , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , Estudos Longitudinais , Prognóstico , Análise de Sobrevida , Fatores de Tempo
14.
CPT Pharmacometrics Syst Pharmacol ; 4(1): e00008, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26225222

RESUMO

Hézode et al. recently reported the frequent occurrence of anemia and thrombocytopenia in the ANRS-CO20-CUPIC cohort of hepatitis C virus (HCV) cirrhotic experienced patients treated with pegylated-interferon (Peg-IFN), ribavirin (RBV), and telaprevir or boceprevir.1,2 Using frequent measurements of serum drug concentrations, hemoglobin, and platelet concentrations obtained in 15 patients of this cohort, we show how an on-treatment model-based approach could be used to individualize dose regimen and avoid the occurrence of RBV-induced anemia and Peg-IFN-induced thrombocytopenia.

15.
Clin Liver Dis ; 3(4): 843-53, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11291254

RESUMO

An important subset of patients with chronic hepatitis C have normal ALT levels despite having detectable HCV RNA in serum. These patients are typically identified after donating blood and being found positive for antibody to HCV (anti-HCV). A strict definition of this patient population is needed, which should include the presence of anti-HCV, detectable HCV RNA by PCR and persistently normal ALT levels. These patients are usually asymptomatic, but on liver biopsy almost all have histologic evidence of chronic hepatitis. The histologic findings generally are mild, and cirrhosis is rare. The long-term outcome of this group of patients with chronic HCV infection is not known, but the prognosis is probably good. In small, uncontrolled trials of IFN-alpha in patients with normal ALT levels, end-of-treatment virologic responses occurred in 42% of patients, and sustained responses 6 to 12 months afterwards in 13% of patients. These rates of response are not very different from those reported in patients with elevated ALT levels. Importantly, in most studies, serum ALT levels became elevated during IFN therapy in approximately one half of patients, and levels remained elevated in some of these patients after therapy. These findings suggest that IFN-alpha therapy is not usually beneficial and may be harmful in chronic hepatitis C patients with normal ALT levels. Combination therapy with IFN and ribavirin has not been evaluated in this group of patients.


Assuntos
Alanina Transaminase/sangue , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/enzimologia , Hepatite C Crônica/patologia , Humanos , Interferon-alfa/uso terapêutico , Fígado/patologia , RNA Viral/sangue
16.
J Thorac Cardiovasc Surg ; 74(2): 286-94, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-881882

RESUMO

Acute myocardial infarction with shock (AMI/S) was produced in 46 anesthetized "closed-chest" dogs by catheter injection of metallic mercury into the circumflex coronary artery. Twenty-four dogs were kept normothermic and 22 were maintained at 32 degrees C. Nine of the latter were rewarmed to 37 degrees C. and the experiments then were terminated, so that true survival time was arbitrarily shortened. Including these dogs, the survival time was three times longer than in the normothermic series (p less than 0.001). Hypothermia reduced heart rate (HR) by 34 percent, oxygen consumption by 38 percent, and myocardial oxygen consumption by an estimated 30 to 40 percent, while cardiac output (CO), stroke volume, and stroke work were unchanged. Left ventricular end-diastolic pressure (LVEDP) was reduced by 40 percent during hypothermia (p less than 0.05) and increased by 60 percent on rewarming. HR during rewarming increased substantially more than CO and thereby significantly reduced stroke volume.


Assuntos
Modelos Animais de Doenças , Hipotermia Induzida , Infarto do Miocárdio/fisiopatologia , Choque Cardiogênico/fisiopatologia , Doença Aguda , Animais , Pressão Sanguínea , Débito Cardíaco , Cães , Feminino , Coração/fisiopatologia , Bloqueio Cardíaco/fisiopatologia , Frequência Cardíaca , Masculino , Contração Miocárdica , Infarto do Miocárdio/mortalidade , Miocárdio/metabolismo , Consumo de Oxigênio , Choque Cardiogênico/mortalidade
17.
Drug Saf ; 24(5): 375-84, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11419564

RESUMO

Interferon-alpha is the most widely used antiviral drug in chronic hepatitis B and C. Tolerability is usually good and serious adverse effects are rare. Most of the adverse effects are mild or transient and do not necessitate drug withdrawal. More than 90% of patients who are given interferon-alpha achieve 6 months to 1 year of treatment without serious adverse effects. The serious adverse effects usually occur in predisposed patients with pre-existing organ dysfunction. Nevertheless, careful selection of patients for therapy and observation during therapy are recommended. Nucleoside analogues are promising drugs in the treatment of chronic hepatitis B through inhibition of viral DNA polymerase. Lamivudine has been licensed for use in this indication. Its tolerability is excellent even when used for periods of 1 year or more. The main concern is the relatively high incidence of viral resistance resulting in breakthrough during or relapse after therapy. In the treatment of chronic hepatitis C, ribavirin, in combination with interferon-alpha is currently the reference therapy. The main adverse effect is haemolytic anaemia, which necessitates careful monitoring and adjustment of dosage in many cases. Recently, large trials showed the better efficacy of pegylated interferons as compared with standard interferon. The combination of pegylated interferon with ribavirin is under evaluation.


Assuntos
Antivirais/efeitos adversos , Hepatite B/prevenção & controle , Hepatite C/prevenção & controle , Humanos , Interferon-alfa/efeitos adversos , Interleucina-2/efeitos adversos , Nucleosídeos , Timopentina/efeitos adversos
18.
Clin Biochem ; 32(7): 537-45, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10614716

RESUMO

OBJECTIVES: To utilize cytokine levels to predict sustained response (SR) to alpha interferon (IFN alpha) therapy in chronic hepatitis C patients, and to determine the relationship between serum tumor necrosis factor alpha (TNF alpha), interleukin (IL) IL 6, IL 8, IL 12, transforming growth factor beta (TGF beta 1) and the degree of liver damage as reflected by traditional markers. DESIGN AND METHODS: Serum cytokine levels were assessed using ELISA in 18 patients included in a controlled clinical trial of IFN alpha. RESULTS: Of the 18 patients, 27% were sustained responders (SR), 27% were response and relapse responders (RR), and 46% were non-responders (NR). Multivariate analysis showed that a low serum TNF alpha level and high serum IL 8 levels were independent factors associated with SR to IFN alpha therapy. Serum TNF alpha level highly correlated with viral load and genotype predictive values (p < 0.001). Therapy lowered the IL 6 and IL 12 profile. TGF beta 1 levels in serum are positively correlated with fibrinogenesis. CONCLUSIONS: IFN alpha therapy modulates immune response to hepatitis C virus, contributing to sustained response.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Idoso , Feminino , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Humanos , Interleucinas/sangue , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta/sangue , Resultado do Tratamento
19.
Clin Biochem ; 34(3): 173-82, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11408014

RESUMO

OBJECTIVES: (i) To characterize serum cytokine levels of tumor necrosis factor alpha (TNF alpha), interleukin 6 (IL 6), IL 8 and IL 12 in non-cirrhotic patients with chronic hepatitis C, (ii) to correlate the levels of these cytokines with the degree of the disease at the basal level, (iii) to correlate these levels with the response to therapy, (iv) to compare profiles of cytokines in monotherapy (MT) versus combination therapy (CT), and (v) to compare the immunomodulatory effects of MT versus CT. DESIGN AND METHODS: 47 patients were enrolled in the study. The controls were 120 volunteers (recruited from students and staff) that did not present HCV RNA positive and were not known to suffer any other metabolic disease. Thirty patients formed the other group of controls, with alcoholic liver disease (ALD). Serum cytokine levels were assessed using enzyme-linked immunosorbent assay (ELISA). RESULTS: The sustained responders (SRs) have basal values much lower than relapsed responders (RRs) and non-responders (NRs) regardless of the therapy. CONCLUSIONS: Cytokines can be used as non-invasive markers for sustained response and as monitors for the outcome of therapy.


Assuntos
Biomarcadores , Hepatite C Crônica/imunologia , Interferons/uso terapêutico , Interleucinas/sangue , Ribavirina/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Alanina Transaminase/sangue , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/sangue , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferons/administração & dosagem , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Ribavirina/administração & dosagem , Carga Viral
20.
J Vestib Res ; 6(2): 61-70, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8925117

RESUMO

Acetylcholinesterase (AchE) activity was studied in pigmented rats 6 h to 1 y after hemilabyrinthectomy. A strong reduction of this activity was localized in the rostrocaudal extent of both the prepositus hypoglossi nucleus and the medial vestibular nucleus (that is, medial vestibular complex: VCm) ipsilateral to the lesion 6 h after the lesion. This deficit persisted within some areas dispersed throughout this complex 3 w and 1 y postoperatively. This result supports the hypothesis that the asymmetry of AchE activity in VCm could be necessary for vestibular compensation and provides an additional model for functional plasticity in the central nervous system.


Assuntos
Acetilcolinesterase/metabolismo , Orelha Interna/fisiologia , Eminência Mediana/enzimologia , Substância Cinzenta Periaquedutal/enzimologia , Núcleos Vestibulares/enzimologia , Animais , Orelha Interna/cirurgia , Histocitoquímica , Ratos
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