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1.
Sci Rep ; 11(1): 21286, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711878

RESUMO

Phenotypic diversity in urinary metabolomes of different geographical populations has been recognized recently. In this study, urinary metabolic signatures from Western (United Kingdom) and South-East Asian (Thai) cholangiocarcinoma patients were characterized to understand spectral variability due to host carcinogenic processes and/or exogenous differences (nutritional, environmental and pharmaceutical). Urinary liquid chromatography mass spectroscopy (LC-MS) spectral profiles from Thai (healthy = 20 and cholangiocarcinoma = 14) and UK cohorts (healthy = 22 and cholangiocarcinoma = 10) were obtained and modelled using chemometric data analysis. Healthy metabolome disparities between the two distinct populations were primarily related to differences in dietary practices and body composition. Metabolites excreted due to drug treatment were dominant in urine specimens from cholangiocarcinoma patients, particularly in Western individuals. Urine from participants with sporadic (UK) cholangiocarcinoma contained greater levels of a nucleotide metabolite (uridine/pseudouridine). Higher relative concentrations of 7-methylguanine were observed in urine specimens from Thai cholangiocarcinoma patients. The urinary excretion of hippurate and methyladenine (gut microbial-host co-metabolites) showed a similar pattern of lower levels in patients with malignant biliary tumours from both countries. Intrinsic (body weight and body composition) and extrinsic (xenobiotic metabolism) factors were the main causes of disparities between the two populations. Regardless of the underlying aetiology, biological perturbations associated with cholangiocarcinoma urine metabolome signatures appeared to be influenced by gut microbial community metabolism. Dysregulation in nucleotide metabolism was associated with sporadic cholangiocarcinoma, possibly indicating differences in mitochondrial energy production pathways between cholangiocarcinoma tumour subtypes. Mapping population-specific metabolic disparities may aid in interpretation of disease processes and identification of candidate biomarkers.


Assuntos
Variação Biológica da População , Biomarcadores/urina , Colangiocarcinoma/epidemiologia , Colangiocarcinoma/urina , Metaboloma , Metabolômica , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Vigilância da População , Tailândia/epidemiologia , Reino Unido/epidemiologia
2.
J Clin Exp Hepatol ; 10(1): 17-29, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32025163

RESUMO

BACKGROUND: A distinct serum metabonomic pattern has been previously revealed to be associated with various forms of liver disease. Here, we aimed to apply mass spectrometry to obtain serum metabolomic profiles from individuals with cholangiocarcinoma and benign hepatobiliary diseases to gain an insight into pathogenesis and search for potential early-disease biomarkers. METHODS: Serum samples were profiled using a hydrophilic interaction liquid chromatography platform, coupled to a mass spectrometer. A total of 47 serum specimens from 8 cholangiocarcinoma cases, 20 healthy controls, 8 benign disease controls (bile duct strictures) and 11 patients with hepatocellular carcinoma (as malignant disease controls) were included. Data analysis was performed using univariate and multivariate statistics. RESULTS: The serum metabolome disparities between the metabolite profiles from healthy controls and patients with hepatobiliary disease were predominantly related to changes in lipid and lipid-derived compounds (phospholipids, bile acids and steroids) and amino acid metabolites (phenylalanine). A metabolic pattern indicative of inflammatory response due to cirrhosis and cholestasis was associated with the disease groups. The abundance of phospholipid metabolites was altered in individuals with liver disease, particularly cholangiocarcinoma, but no significant difference was seen between profiles from patients with benign biliary strictures and cholangiocarcinoma. CONCLUSION: The serum metabolome in cholangiocarcinoma exhibited changes in metabolites related to inflammation, altered energy production and phospholipid metabolism. This study serves to highlight future avenues for biomarker research in large-scale studies.

3.
Hepat Med ; 11: 47-67, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118840

RESUMO

Background: Outside South-East Asia, most cases of cholangiocarcinoma (CCA) have an obscure etiology. There is often diagnostic uncertainty. Metabolomics using ultraperformance liquid chromatography mass spectrometry (UPLC-MS) offers the portent to distinguish disease-specific metabolic signatures. We aimed to define such a urinary metabolic signature in a patient cohort with sporadic CCA and investigate whether there were characteristic differences from those in patients with hepatocellular carcinoma (HCC), metastatic secondary liver cancer, pancreatic cancer and ovarian cancer (OCA). Methods: Spot urine specimens were obtained from 211 subjects in seven participating centers across the UK. Samples were collected from healthy controls and from patients with benign hepatic disease (gallstone, biliary strictures, sphincter of Oddi dysfunction and viral hepatitis) and patients with malignant conditions (HCC, pancreatic cancer, OCA and metastatic cancer in the liver). The spectral metabolite profiles were generated using a UPLC-MS detector and data were analyzed using multivariate and univariate statistical analyses. Results: The greatest class differences were seen between the metabolic profiles of disease-free controls compared to individuals with CCA with altered acylcarnitine, bile acid and purine levels. Individuals with benign strictures showed comparable urine profiles to patients with malignant bile duct lesions. The metabolic signatures of patients with bile duct tumors were distinguishable from patients with hepatocellular and ovarian tumors, but no difference was observed between CCA cases and patients with pancreatic cancer or hepatic secondary metastases. Conclusion: CCA causes subtle but detectable changes in the urine metabolic profiles. The findings point toward potential applications of metabonomics in early tumor detection. However, it is key to utilize both global and targeted metabonomics in a larger cohort for in-depth characterization of the urine metabolome in hepato-pancreato-biliary disease.

4.
J Clin Exp Hepatol ; 6(3): 186-194, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27746614

RESUMO

BACKGROUND: Discriminatory metabolic profiles have been described in urinary 1H nuclear magnetic resonance (NMR) spectroscopy studies of African patients with hepatocellular carcinoma (HCC). This study aimed to assess similarities in a UK cohort, where there is a greater etiological diversity. METHODS: Urine from cirrhosis and HCC patients was analyzed using a 600 MHz 1H NMR system. Multivariate analysis and median group MR spectra comparison identified metabolite alterations between groups. Metabolite identification was achieved through literature reference and statistical total correlation spectroscopy. Diagnostic accuracy was compared to serum alpha-fetoprotein (AFP). RESULTS: Of the 52 patients recruited, 13 samples from HCC and 25 from cirrhosis patients were selected. At 200 IU mL-1, diagnostic sensitivity of AFP was 27%. Multivariate analysis of urinary spectra generated diagnostic models with a sensitivity/specificity of 53.6%/96%. p-Cresol sulfate (P = 0.04), creatinine (P = 0.03), citrate (P = 0.21) and hippurate (P = 0.52) were reduced in the HCC patients. Carnitine (P = 0.31) and formate (P = 0.44) were elevated. CONCLUSION: Diagnostic sensitivity was lower than previous African studies, but still outperformed serum AFP. Reduced creatinine, citrate and hippurate and elevated carnitine are comparable with the African studies. p-Cresol sulfate alteration is a novel finding and may indicate an altered sulfonation capacity of the liver in patients with HCC.

5.
Int J Psychiatry Med ; 51(2): 201-10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27079778

RESUMO

Autism spectrum disorder (previously known as pervasive developmental disorders) is characterized by social communication deficits, impaired functioning, and restrictive or repetitive behaviors and interests. Patients with autism spectrum disorder also commonly experience core maladaptive behaviors such as aggression and irritability, self-injurious behaviors, hyperactivity, and sleep abnormalities. These behaviors may be sources of stress for caregivers and patients alike and may require pharmacologic management. Risperidone and aripiprazole are frequently used to treat both irritability and self-injurious behavior related to autism spectrum disorder. The opioid antagonist naltrexone has also been studied for self-injurious behaviors, although long-term data are lacking when used in the autism spectrum disorder population. Methylphenidate, atomoxetine, clonidine, and guanfacine are all potential options for the treatment of hyperactivity or attention-deficient hyperactivity disorder-like symptoms in patients with autism spectrum disorder. Lastly, melatonin is the most widely researched medication strategy for the management of sleep disorders in autism spectrum disorder. Future studies reviewing new pharmacologic treatment approaches in combination with non-pharmacologic therapies are warranted to ensure that target behaviors of autism spectrum disorder are appropriately managed.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/tratamento farmacológico , Humanos
6.
J Pharm Pract ; 29(3): 250-2, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26739480

RESUMO

PURPOSE: To report a case of hypothermia in a patient with intellectual disability treated with thioridazine. SUMMARY: A 59-year-old female presented to the emergency department with altered mental status, generalized weakness, chills, and fatigue and was diagnosed with a urinary tract infection. Upon completion of a history and physical examination, the patient was found to be hypothermic with a temperature of 91 F. A Bair Hugger protocol was initiated to manage hypothermia, and a taper schedule for thioridazine was initiated as it was identified as a possible culprit for the patient's hypothermia. According to the Naranjo probability scale, thioridazine was a possible cause of this adverse effect. Other patient-specific risk factors for hypothermia were evaluated and ruled out. CONCLUSION: This case indicates a possible correlation between hypothermia and the use of phenothiazine antipsychotics such as thioridazine. Appropriate measures, including early detection and identification of possible causative agents, should be taken to prevent and treat this adverse event in patients taking these medications, specifically in patients with the inability to participate in self-care.


Assuntos
Antipsicóticos/efeitos adversos , Hipotermia/induzido quimicamente , Hipotermia/diagnóstico , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/tratamento farmacológico , Tioridazina/efeitos adversos , Feminino , Humanos , Hipotermia/psicologia , Deficiência Intelectual/psicologia , Pessoa de Meia-Idade
7.
Hepatology ; 60(4): 1211-21, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25043514

RESUMO

There is no licensed treatment for non-alcoholic fatty liver disease (NAFLD), a condition that increases risk of chronic liver disease, type 2 diabetes and cardiovascular disease. We tested whether 15-18 months treatment with docosahexaenoic acid (DHA) plus eicosapentaenoic acid (EPA) (Omacor/Lovaza) (4 g/day) decreased liver fat and improved two histologically-validated liver fibrosis biomarker scores (primary outcomes). Patients with NAFLD were randomised in a double blind placebo-controlled trial [DHA+EPA(n=51), placebo(n=52)]. We quantified liver fat percentage (%) by magnetic resonance spectroscopy in three liver zones. We measured liver fibrosis using two validated scores. We tested adherence to the intervention (Omacor group) and contamination (with DHA and EPA) (placebo group) by measuring erythrocyte percentage DHA and EPA enrichment (gas chromatography). We undertook multivariable linear regression to test effects of: a) DHA+EPA treatment (ITT analyses) and b) erythrocyte DHA and EPA enrichment (secondary analysis). Median (IQR) baseline and end of study liver fat% were 21.7 (19.3) and 19.7 (18.0) (placebo), and 23.0 (36.2) and 16.3 (22.0), (DHA+EPA). In the fully adjusted regression model there was a trend towards improvement in liver fat% with DHA+EPA treatment (ß=-3.64 (95%CI -8.0,0.8); p=0.1) but there was evidence of contamination in the placebo group and variable adherence to the intervention in the Omacor group. Further regression analysis showed that DHA enrichment was independently associated with a decrease in liver fat% (for each 1% enrichment, ß=-1.70 (95%CI -2.9,-0.5); p=0.007). No improvement in the fibrosis scores occurred. Conclusion. Erythrocyte DHA enrichment with DHA+EPA treatment is linearly associated with decreased liver fat%. Substantial decreases in liver fat% can be achieved with high percentage erythrocyte DHA enrichment in NAFLD. (Hepatology 2014;).


Assuntos
Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Fármacos Gastrointestinais/administração & dosagem , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Adulto , Ácidos Docosa-Hexaenoicos/análise , Método Duplo-Cego , Ácido Eicosapentaenoico/análise , Eritrócitos/química , Feminino , Humanos , Cirrose Hepática/patologia , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade
8.
BMJ Case Rep ; 20142014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24599428

RESUMO

Nitrofurantoin is recommended for first line prophylaxis of recurrent urinary tract infections. Despite a number of side effects it is increasingly prescribed due to its high efficacy, low cost and minimal antimicrobial resistance. Nitrofurantoin-induced immune-mediated liver injury is a particularly serious complication, resulting in both acute hepatic failure and cirrhosis with continued use. We describe the course of two patients who recently presented to our hospital in order to highlight this.


Assuntos
Anti-Infecciosos Urinários/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatite Autoimune/patologia , Fígado/patologia , Nitrofurantoína/efeitos adversos , Idoso , Biópsia , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Feminino , Hepatite Autoimune/imunologia , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Pessoa de Meia-Idade
9.
Ophthalmology ; 120(8): 1612-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23562165

RESUMO

PURPOSE: To investigate whether modification of liver complement factor H (CFH) production, by alteration of liver CFH Y402H genotype through liver transplantation (LT), influences the development of age-related macular degeneration (AMD). DESIGN: Multicenter, cross-sectional study. PARTICIPANTS: We recruited 223 Western European patients ≥ 55 years old who had undergone LT ≥ 5 years previously. METHODS: We determined AMD status using a standard grading system. Recipient CFH Y402H genotype was obtained from DNA extracted from recipient blood samples. Donor CFH Y402H genotype was inferred from recipient plasma CFH Y402H protein allotype, measured using enzyme-linked immunosorbent assays. This approach was verified by genotyping donor tissue from a subgroup of patients. Systemic complement activity was ascertained by measuring levels of plasma complement proteins using an enzyme-linked immunosorbent assay, including substrates (C3, C4), activation products (C3a, C4a, and terminal complement complex), and regulators (total CFH, C1 inhibitor). MAIN OUTCOME MEASURES: We evaluated AMD status and recipient and donor CFH Y402H genotype. RESULTS: In LT patients, AMD was associated with recipient CFH Y402H genotype (P = 0.036; odds ratio [OR], 1.6; 95% confidence interval [CI], 1.0-2.4) but not with donor CFH Y402H genotype (P = 0.626), after controlling for age, sex, smoking status, and body mass index. Recipient plasma CFH Y402H protein allotype predicted donor CFH Y402H genotype with 100% accuracy (n = 49). Plasma complement protein or activation product levels were similar in LT patients with and without AMD. Compared with previously reported prevalence figures (Rotterdam Study), LT patients demonstrated a high prevalence of both AMD (64.6% vs 37.1%; OR, 3.09; P<0.001) and the CFH Y402H sequence variation (41.9% vs 36.2%; OR, 1.27; P = 0.014). CONCLUSIONS: Presence of AMD is not associated with modification of hepatic CFH production. In addition, AMD is not associated with systemic complement activity in LT patients. These findings suggest that local intraocular complement activity is of greater importance in AMD pathogenesis. The high AMD prevalence observed in LT patients may be associated with the increased frequency of the CFH Y402H sequence variation. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.


Assuntos
Transplante de Fígado , Fígado/metabolismo , Degeneração Macular/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Fator H do Complemento/genética , Fator H do Complemento/metabolismo , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Técnicas de Genotipagem , Humanos , Degeneração Macular/sangue , Masculino , Doadores de Tecidos , Transplante
10.
World J Gastroenterol ; 16(42): 5317-23, 2010 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21072894

RESUMO

AIM: To investigate if antibiotics administered within 8 h of endoscopy reduce mortality or increase the incidence of Clostridium difficile infection (CDI). METHODS: A 2-year retrospective analysis of all patients who presented with first variceal hemorrhage was undertaken. The primary outcome measure was 28-d mortality. Secondary outcome measures were 28-d rebleeding rates and 28-d incidence of CDI. All patients were admitted to a tertiary liver unit with a consultant-led, 24-h endoscopy service. Patients received standard care including terlipressin therapy. Data collection included: primary and secondary outcome measures, timing of first administration of intravenous antibiotics, etiology of liver disease, demographics, endoscopy details and complications. A prospective study was undertaken to determine the incidence of CDI in the study population and general medical inpatients admitted for antibiotic therapy of at least 5 d duration. Statistical analysis was undertaken using univariate, non-parametric tests and multivariate logistic regression analysis. RESULTS: There were 70 first presentations of variceal hemorrhage during the study period. Seventy percent of cases were male and 65.7% were due to chronic alcoholic liver disease. In total, 64/70 (91.4%) patients received antibiotics as prophylaxis during their admission. Specifically, 53/70 (75.7%) received antibiotics either before endoscopy or within 8 h of endoscopy [peri-endoscopy (8 h) group], whereas 17/70 (24.3%) received antibiotics at > 8 h after endoscopy or not at all (non peri-endoscopy group). Overall mortality and rebleeding rates were 13/70 (18.6%) and 14/70 (20%), respectively. The peri-endoscopy (8 h) group was significantly less likely to die compared with the non peri-endoscopy group [13.2% vs 35.3%, P = 0.04, odds ratio (OR) = 0.28 (0.078-0.997)] and showed a trend towards reduced rebleeding [17.0% vs 29.4%, P = 0.27, OR = 0.49 (0.14-1.74)]. On univariate analysis, the non peri-endoscopy group [P = 0.02, OR = 3.58 (1.00-12.81)], higher model for end-stage liver disease (MELD) score (P = 0.02), presence of hepatorenal syndrome [P < 0.01, OR = 11.25 (2.24-56.42)] and suffering a clinical episode of sepsis [P = 0.03, OR = 4.03 (1.11-14.58)] were significant predictors of death at 28 d. On multivariate logistic regression analysis, lower MELD score [P = 0.01, OR = 1.16 (1.04-1.28)] and peri-endoscopy (8 h) group [P = 0.01, OR = 0.15 (0.03-0.68)] were independent predictors of survival at 28 d. The CDI incidence (5.7%) was comparable to that in the general medical population (5%). CONCLUSION: Antibiotics administered up to 8 h following endoscopy were associated with improved survival at 28 d. CDI incidence was comparable to that in other patient groups.


Assuntos
Antibacterianos , Antibioticoprofilaxia , Clostridioides difficile/efeitos dos fármacos , Infecções por Clostridium , Endoscopia , Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal , Adulto , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Clostridium/etiologia , Infecções por Clostridium/prevenção & controle , Endoscopia/efeitos adversos , Varizes Esofágicas e Gástricas/microbiologia , Varizes Esofágicas e Gástricas/mortalidade , Varizes Esofágicas e Gástricas/cirurgia , Feminino , Hemorragia Gastrointestinal/microbiologia , Hemorragia Gastrointestinal/mortalidade , Hemorragia Gastrointestinal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida
11.
World J Gastroenterol ; 16(32): 4061-5, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-20731020

RESUMO

AIM: To investigate and characterise patients with chronic hepatitis C virus (HCV) infection presenting with hepatocellular carcinoma (HCC) in the absence of cirrhosis. METHODS: Patients with chronic hepatitis C infection without cirrhosis presenting with HCC over a 2-year period were identified. The clinical case notes, blood test results and histological specimens were reviewed to identify whether additional risk factors for the development of HCC were present. RESULTS: Six patients (five male, one female) with chronic hepatitis C infection without cirrhosis presented to a single centre with HCC over a 2-year period. Five patients were treated by surgical resection and one patient underwent liver transplantation. Evaluation of generous histological specimens confirmed the presence of HCC and the absence of cirrhosis in all cases. The degree of fibrosis of the background liver was staged as mild (n = 1), moderate (n = 4) or bridging fibrosis (n = 1). Review of the clinical case notes revealed that all cases had an additional risk factor for the development of HCC (four had evidence of past hepatitis B virus infection; two had a history of excessive alcohol consumption; a further patient had prolonged exposure to immune suppression). CONCLUSION: HCC does occur in patients with non-cirrhotic HCV infection who have other risk factors for hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/etiologia , Hepatite C Crônica/complicações , Cirrose Hepática/fisiopatologia , Neoplasias Hepáticas/etiologia , Idoso , Anticorpos Antivirais/sangue , Carcinoma Hepatocelular/fisiopatologia , Carcinoma Hepatocelular/terapia , Feminino , Hepacivirus/genética , Vírus da Hepatite B/imunologia , Hepatite C Crônica/fisiopatologia , Humanos , Neoplasias Hepáticas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
Adv Ther ; 27(8): 512-22, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20652658

RESUMO

More than 180 million people worldwide have chronic hepatitis C (CHC) virus infection, a major cause of liver cirrhosis and its life-threatening complications including liver failure, portal hypertension, and hepatocellular carcinoma. With the current standard of care of pegylated interferon-alpha and ribavirin (PEG-IFN-alpha/RBV), the chances of sustained viral clearance or "cure" are only 40%-50% for genotype 1 infection, which is the most common genotype in western populations. Consequently, there has been a drive to develop new agents specifically targeting essential components of the viral life cycle, such as the hepatitis C virus (HCV) NS3/4A serine protease. Perhaps the most advanced HCV protease inhibitor in clinical development is telaprevir, which has been shown to improve treatment outcomes when combined with PEG-IFN-alpha/RBV in genotype 1 infection, and is currently undergoing phase 3 study. In this review, we summarize the pharmacology, pharmacokinetics, and results of phase 1 and 2 clinical trials of telaprevir, and discuss the likely role of this agent in the future management of CHC.


Assuntos
Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos , Antivirais/uso terapêutico , Ensaios Clínicos como Assunto , Sinergismo Farmacológico , Predisposição Genética para Doença , Hepacivirus/genética , Hepatite C Crônica/complicações , Hepatite C Crônica/genética , Hepatite C Crônica/fisiopatologia , Humanos , Interferon-alfa/uso terapêutico , Cirrose Hepática/etiologia , Oligopeptídeos/farmacologia , Ribavirina/uso terapêutico , Inibidores de Serina Proteinase/genética , Inibidores de Serina Proteinase/uso terapêutico , Resultado do Tratamento
15.
Adv Ther ; 26(2): 155-69, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19225726

RESUMO

INTRODUCTION: The treatment of chronic hepatitis B virus (HBV) infection has been revolutionized in the past decade by the increased availability of effective antiviral agents. Telbivudine is an L-nucleoside that is structurally related to lamivudine and has recently been approved for use in patients with chronic HBV infection. Telbivudine is highly selective for HBV DNA and inhibits viral DNA synthesis with no effect on human DNA or other viruses. This article reviews the pharmacology, pharmacokinetics, therapeutic efficacy and safety of telbivudine, and discusses its place in the current armamentarium against HBV. METHODS: Relevant publications were identified from searches of Medline and PubMed between 2000 and 2008, using the search terms "hepatitis B/HBV," "telbivudine/LdT," "beta-L-thymidine," "pharmacokinetics," "safety," "adverse events," and "resistance." The reference lists of retrieved articles were searched for relevant studies. RESULTS: Phase 3 clinical studies demonstrate that telbivudine is superior to lamivudine over a 2-year period in hepatitis B e-antigen (HBeAg)-positive and HBeAg-negative patients. Telbivudine was associated with a statistically significantly greater reduction in HBV DNA, greater proportion of alanine aminotransferase normalization, and greater histological response than lamivudine. Furthermore, telbivudine use resulted in fewer cases of treatment failure and less virological resistance than lamivudine. However, after 2 years of therapy, telbivudine resistance was appreciable (25%) and considerably higher than that seen with other new antivirals such as tenofovir and entecavir. Overall, telbivudine was found to be safe, although grade 3 or 4 adverse events, including elevations in creatine kinase, were more commonly found in patients receiving telbivudine than lamivudine. Telbivudine is not active against lamivudine-resistant HBV. CONCLUSIONS: Telbivudine is a new antiviral agent joining the armamentarium against HBV. It is superior to lamivudine in terms of therapeutic response and resistance profile. However, concerns about resistance with long-term use, along with inferior cost-effective analyses, have relegated telbivudine to a second-line agent in the management of chronic HBV infection.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Nucleosídeos/uso terapêutico , Pirimidinonas/uso terapêutico , Alanina Transaminase/sangue , Alanina Transaminase/efeitos dos fármacos , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , DNA Viral/biossíntese , DNA Viral/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Interações Medicamentosas , Farmacorresistência Viral/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/metabolismo , Hepatite B Crônica/virologia , Humanos , Nucleosídeos/química , Nucleosídeos/farmacologia , Pirimidinonas/química , Pirimidinonas/farmacologia , Segurança , Telbivudina , Timidina/análogos & derivados , Resultado do Tratamento , Replicação Viral/efeitos dos fármacos
16.
Lancet Infect Dis ; 8(7): 444-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18485825

RESUMO

The treatment of hepatitis B virus (HBV) infection has been revolutionised in the past decade by the increased availability of effective antiviral agents. Many studies have shown the benefits of single agent therapy, but there is an alarming and rising rate of viral resistance, and clear evidence that viruses that harbour resistant mutations can cause liver disease and death. Current national guidelines for the treatment of HBV recommend a programme that starts with monotherapy, followed by sequential monotherapy or add-on therapy for those infections in which mutations have arisen. Very few studies starting with combination therapy have been undertaken, so there is little evidence of the clinical benefit of this approach to treatment. The studies that have been done have been short term and have concentrated on clinical parameters rather than virological resistance, which is likely to be the key determinant in the longer term. We argue that we should not wait for the evidence to use combination therapy for the treatment of HBV, since such trials may never be done and it would take several years for a benefit to become apparent. In the meantime, multidrug-resistant strains continue to hinder HBV control.


Assuntos
Antivirais/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Antivirais/uso terapêutico , Farmacorresistência Viral , Quimioterapia Combinada , Vírus da Hepatite B/efeitos dos fármacos , Humanos
18.
J Gene Med ; 6(9): 974-83, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15352070

RESUMO

BACKGROUND: For many applications, efficient gene therapy will require long-term, organ-specific therapeutic gene expression. Lentiviral vectors based on HIV-1 are promising gene delivery vehicles due to their ability to integrate transgenes into non-dividing cells. Many experimental vectors express transgenes under the control of the cytomegalovirus (CMV) immediate-early gene promoter. Although this promoter directs strong gene expression in vitro, it may be shut off rapidly in vivo. This study explores the potential of HIV-1-based vectors to transduce hepatocytes and compares gene expression from different promoters in integrated vectors. METHODS: HIV-1-based vector plasmids expressing the green fluorescent protein (GFP) under the control of the CMV promoter, the alpha-1 antitrypsin gene promoter or promoters derived from the hepatitis B virus (HBV) genome were used to compare expression in transfected and transduced cell lines. RESULTS: Hepatocyte cell lines differed strikingly in their transfectability. Transduction with replication-deficient HIV-1-based vector particles incorporating the different promoter elements was uniformly effective in hepatocyte and non-hepatocyte lines. However, in hepatocytes, only the CMV, alpha-1 antitrypsin and HBV core but not HBV surface promoters were able to produce GFP expression. Addition of the HBV enhancer 2 element improved the transducing ability of the HBV surface promoter and suppressed expression in non-hepatocytes increasing specificity for hepatocytes. CONCLUSIONS: Integrated lentiviral vectors can be used to direct transgene expression in liver cells both promiscuously and specifically. Promoters derived from the alpha-1 antitrypsin gene or HBV are alternatives to the CMV promoter. Inclusion of the HBV enhancer 2 permits strong liver-specific gene expression in vitro.


Assuntos
Regulação Viral da Expressão Gênica , Terapia Genética , Vetores Genéticos/genética , HIV-1/genética , Hepatócitos/metabolismo , Fusão Gênica Artificial , Linhagem Celular , Citomegalovirus/genética , Elementos Facilitadores Genéticos , Técnicas de Transferência de Genes , Genes Reporter/genética , Genes Reporter/fisiologia , Vetores Genéticos/uso terapêutico , Proteínas de Fluorescência Verde/genética , HIV-1/fisiologia , Vírus da Hepatite B/genética , Hepatócitos/virologia , Humanos , Regiões Promotoras Genéticas/fisiologia , Transdução Genética , Transfecção , Integração Viral/fisiologia , alfa 1-Antitripsina/genética
19.
Hosp Med ; 64(4): 200-4, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12731130

RESUMO

Liver transplantation has evolved from an experimental procedure to an acceptable therapy for end-stage liver disease. The major challenges now faced are donor organ shortage, long-term complications related to immunosuppressive therapy, and the prevention and treatment of disease recurrence.


Assuntos
Transplante de Fígado , Rejeição de Enxerto/etiologia , Humanos , Terapia de Imunossupressão , Infecções/etiologia , Seleção de Pacientes , Complicações Pós-Operatórias/etiologia , Prognóstico , Recidiva , Reoperação , Doadores de Tecidos
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