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1.
J Hepatol ; 73(1): 62-71, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32061869

RESUMO

BACKGROUND & AIMS: The outcome of HBV infection, including the dynamics of HBsAg and HBV virological reactivation, among patients coinfected with HCV receiving direct-acting antivirals (DAAs) remains unclear. Thus, we aimed to analyze HBV-related outcomes in these patients. METHODS: Serial HBsAg and HBV DNA levels were measured in 79 HBV/HCV-coinfected patients receiving DAAs (13 receiving anti-HBV nucleot(s)ide analog [NUC] therapy simultaneously). The endpoints included HBsAg dynamics and seroclearance, HBV reactivation (HBV DNA >1 log increase or >100 IU/ml if undetectable at baseline) and HBV-related clinical reactivation. RESULTS: HBsAg levels declined from a median of 73.3 IU/ml at baseline to 16.2 IU/ml at the end-of-DAA treatment and increased to 94.1 IU/ml at 12 months post-treatment. During a mean 11.1-months of follow-up, 8 (10.1%) patients experienced HBsAg seroclearance and 30 (38.0%) HBV reactivation (12-month cumulative incidence, 10.3% and 40.4%, respectively). Patients with pre-treatment HBsAg ≤10 IU/ml had a significantly higher rate of HBsAg seroclearance (hazard ratio [HR] 8.52; 95% CI 1.048-69.312) and lower risk of HBV reactivation than those with pre-treatment HBsAg >10 IU/ml (HR 2.88; 95% CI 1.057-7.844) in multivariate analyses. Six patients (4 cirrhotics) not receiving NUC therapy experienced HBV-related clinical reactivation; 3 of the 4 cirrhotics developed liver failure and 2 died despite immediate NUC therapy. Compared to untreated HBV-monoinfected patients, HBV/HCV-coinfected patients without NUC prophylaxis had a similar rate of HBsAg seroclearance, but a significantly higher risk of HBV reactivation following DAA therapy (HR 6.59; 95% CI 2.488-17.432). CONCLUSIONS: DAA-treated HBV/HCV-coinfected patients had significantly higher rates of HBV seroclearance, particularly among those with low pre-treatment HBsAg titer, but were at higher risk of HBV reactivation, particularly among those with higher pre-treatment HBsAg titer. Prophylactic anti-HBV therapy is essential for cirrhotic patients, irrespective of baseline HBV DNA levels. LAY SUMMARY: We studied outcomes relating to hepatitis B virus (HBV) in patients coinfected with both hepatitis B and C. Patients receiving direct-acting antiviral treatment for hepatitis C were more likely to experience seroclearance (or functional cure of HBV), but were also more likely to experience HBV reactivation, which can lead to hepatitis, liver failure and death. In coinfected cirrhotic patients being treated for HCV, prophylactic treatment for HBV is mandatory.


Assuntos
Antivirais/uso terapêutico , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B , Hepatite B Crônica , Hepatite C Crônica , Ativação Viral , Idoso , Coinfecção/epidemiologia , DNA Viral/isolamento & purificação , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/imunologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/imunologia , Humanos , Masculino , Conduta do Tratamento Medicamentoso/normas , Medição de Risco , Fatores de Risco , Prevenção Secundária/métodos , Taiwan/epidemiologia , Ativação Viral/efeitos dos fármacos , Ativação Viral/imunologia
2.
Eur J Gastroenterol Hepatol ; 30(1): 27-32, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29049126

RESUMO

OBJECTIVES: Direct-acting antiviral agents have revolutionized hepatitis C therapy, and are also found to be effective in the liver transplant setting. The extent of liver fibrosis influences patient management and is used to monitor therapeutic effects. Shear-wave elastography (SWE) is a relatively new imaging-based method that has not yet been studied extensively in liver transplant patients. Our aim was to study the effect of direct-acting antivirals in heaptitis C recurrence on liver stiffness determined by SWE. PATIENTS AND METHODS: A total of 23 liver transplant patients with hepatitis C recurrence were enrolled in this prospective study. The patients underwent 24 weeks of ombitasvir/paritaprevir/ritonavir+dasabuvir±ribavirin combination therapy. Elastographic examinations, serological tests and laboratory tests were performed, and serum biomarkers of liver fibrosis were calculated the day before treatment (baseline) and at the end of the treatment. RESULTS: All our patients became hepatitis C virus RNA negative by the end of the treatment. Median liver stiffness values decreased significantly after treatment compared with baseline (8.72±3.77 vs. 7.19±2.4 kPa; P<0.001). Among the studied laboratory values, a significant decrease was observed in the levels of alanine aminotransferase, aspartate aminotransferase and γ-glutamyltransferase, whereas international normalized ratio levels increased. Serum biomarkers, namely aspartate aminotransferase-to-platelet ratio index and Fibrosis-4, decreased significantly after treatment compared with baseline. CONCLUSION: In the present study, SWE was succesfully used to monitor the beneficial therapeutic effects of direct-acting antivirals in hepatitis C recurrence following liver transplantation. We believe that SWE is a useful noninvasive diagnostic tool in the follow-up of hepatitis C treatment in liver transplant patients.


Assuntos
Antivirais/uso terapêutico , Técnicas de Imagem por Elasticidade , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Transplante de Fígado/efeitos adversos , Ativação Viral/efeitos dos fármacos , Idoso , Antivirais/efeitos adversos , Ensaios Enzimáticos Clínicos , Feminino , Hepacivirus/genética , Hepacivirus/patogenicidade , Hepatite C Crônica/sangue , Hepatite C Crônica/diagnóstico por imagem , Hepatite C Crônica/virologia , Humanos , Coeficiente Internacional Normatizado , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , RNA Viral/sangue , RNA Viral/genética , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Carga Viral
3.
Exp Clin Transplant ; 15(Suppl 1): 1-5, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28260422

RESUMO

OBJECTIVES: Our goal was to investigate wait times related to hepatitis C virus treatment with direct acting antivirals before versus after liver transplant at a single center as well as wait times for insurance approval for preemptive treatment with these agents after liver transplant. MATERIALS AND METHODS: We retrospectively evaluated hepatitis C virus infections in transplant recipients of deceased liver donations in 2014 and 2015. Demographics, hepatocellular carcinoma incidence, Model for End-Stage Liver Disease scores, and transplant wait times were compared between patients treated before or after liver transplant. Wait times to approval of direct-acting antiviral treatment were evaluated in those untreated before transplant. RESULTS: During our study period, of 67 deceased-donor liver transplants, 21 patients received hepatitis C virus treatment pretransplant (treated group) and 46 patients were not treated pretransplant (untreated group). Twenty-five patients in the untreated group received hepatitis C virus-positive donations, with all in this group treated with direct-acting antivirals. We found no statistically significant differences regarding age, sex, race, donation after cardiac death, or incidence of hepatocellular carcinoma between groups. The treated group had a longer median wait time (287 vs 172 days; P = .02). Twelve of the 46 untreated patients (26.1%) developed biopsy-proven hepatitis C virus-related relapse (median 87 days; range, 55-383 days). Preemptive direct-acting antiviral therapy was initiated at a median of 81 days in the untreated group. CONCLUSIONS: Although treatment of hepatitis C virus before liver transplant is an attractive option to eliminate the risk of complications, it can limit the donor pool for recipients to uninfected donors, significantly increasing wait times in regions with large hepatitis C virus-positive donor pools. Allocation of Model for End-Stage Liver Disease score was not different between the treated and untreated groups. Insurance companies should revise their policies for rapid approval of preemptive direct-acting antiviral treatment after liver transplant.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Transplante de Fígado , Tempo para o Tratamento , Doadores de Tecidos/provisão & distribuição , Adulto , Idoso , Antivirais/efeitos adversos , Seleção do Doador , Esquema de Medicação , Definição da Elegibilidade , Feminino , Hepacivirus/patogenicidade , Hepatite C/complicações , Hepatite C/diagnóstico , Hepatite C/transmissão , Humanos , Seguro Saúde , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Ativação Viral/efeitos dos fármacos , Listas de Espera
4.
Rheumatol Int ; 36(5): 635-41, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26573663

RESUMO

Over the past decade, reactivation of occult hepatitis B virus (HBV) infection has garnered much attention from rheumatologists owing to a number of reports which have indicated the potential risk of biologics in causing this previously ignored infectious complication. Hepatitis due to reactivation of occult HBV infection occurs only occasionally but with high mortality upon occurrence, placing us in a clinical dilemma "to address or not to address?" In this review, we discuss how biological and other immunosuppressive therapies increase the risk of developing reactivation of occult HBV infection and attempt to solve this clinical quandary.


Assuntos
Vírus da Hepatite B , Hepatite B/virologia , Imunossupressores/efeitos adversos , Doenças Reumáticas/tratamento farmacológico , Ativação Viral/efeitos dos fármacos , Hepatite B/induzido quimicamente , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Medição de Risco
5.
Liver Int ; 36(4): 515-21, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26610059

RESUMO

BACKGROUND & AIMS: Orthotopic liver transplant patients with recurrent hepatitis C (HCV) historically have had limited treatment options. Ombitasvir/paritaprevir/ritonavir, dasabuvir and ribavirin (3D+R) was approved by the FDA in December 2014 for liver transplant recipients with recurrent genotype 1 HCV, in whom it is effective and well-tolerated. METHODS: Using a two-phase Markov model, we analysed the cost-effectiveness of 3D+R in liver transplant recipients, the only HCV treatment with FDA approval in this population. As a sensitivity analysis, we also considered the cost-effectiveness of pegylated interferon plus ribavirin, the only other therapy with data from Phase III trials in this population. Patients were given one of three options: 3D+R for 24 weeks, pegylated interferon and ribavirin for 48 weeks (PR48) or no treatment (NT). Patients were then followed through subsequent disease progression until death. Outcome measures analysed were: lifetime risks of liver morbidity and mortality, treatment costs, non-treatment medical expenditures, and quality-adjusted life years. RESULTS: Treatment with 3D+R was associated with a significantly lower lifetime risk of liver-related morbidity and mortality than treatment with PR48 or NT. 3D+R also was associated with a higher gain in quality-adjusted life years (11.3 compared to 8.25 with NT) and lower discounted overall costs ($423,585 compared to $724,757 with NT). CONCLUSIONS: The use of 3D+R for liver transplant recipients with recurrent HCV is an outcome-improving and cost-effective regimen for this population with limited treatment options and large unmet need.


Assuntos
Anilidas , Antivirais , Carbamatos , Custos de Medicamentos , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Hepatite C/economia , Transplante de Fígado/efeitos adversos , Transplante de Fígado/economia , Compostos Macrocíclicos , Ribavirina , Ritonavir , Sulfonamidas , Uracila/análogos & derivados , 2-Naftilamina , Anilidas/economia , Anilidas/uso terapêutico , Antivirais/economia , Antivirais/uso terapêutico , Carbamatos/economia , Carbamatos/uso terapêutico , Análise Custo-Benefício , Ciclopropanos , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/diagnóstico , Hepatite C/mortalidade , Humanos , Lactamas Macrocíclicas , Transplante de Fígado/mortalidade , Compostos Macrocíclicos/economia , Compostos Macrocíclicos/uso terapêutico , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Modelos Econômicos , Fenótipo , Prolina/análogos & derivados , Recidiva , Ribavirina/economia , Ribavirina/uso terapêutico , Fatores de Risco , Ritonavir/economia , Ritonavir/uso terapêutico , Sulfonamidas/economia , Sulfonamidas/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Uracila/economia , Uracila/uso terapêutico , Valina , Carga Viral , Ativação Viral/efeitos dos fármacos
6.
World J Gastroenterol ; 21(15): 4447-56, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25914454

RESUMO

Chronic hepatitis C (CHC) is the most common indication for liver transplantation (LT). Aggressive treatment of hepatitis C virus (HCV) infection before cirrhosis development or decompensation may reduce LT need and risk of HCV recurrence post-LT. Factors associated with increased HCV risk or severity of recurrence include older age, immunosuppression, HCV genotype 1 and high viral load at LT. HCV recurrence post-LT leads to accelerated liver disease and cirrhosis development with reduced graft and patient survival. Currently, interferon (IFN)-based regimens can be used in dual-agent regimens with ribavirin, in triple-agent antiviral strategies with direct-acting antivirals (e.g., protease inhibitors telaprevir or boceprevir), or before transplant in compensated patients to reduce HCV viral load to prevent or reduce the risk of post-LT recurrence and complications; they cannot be used in patients with decompensated cirrhosis. IFN-based regimens are used in less than half of HCV-infected patients waiting for LT due to extremely low efficacy and poor tolerability. However, antiviral therapy is indicated after LT in patients with histologically confirmed CHC despite tolerability issues. Improvements in side effect management have increased survival in patients achieving therapeutic targets. HCV treatment pre- and post-LT results in significant health care costs especially when lack of efficacy leads to disease worsening, although studies have shown sofosbuvir treatment before LT vs conventional post-LT dual antiviral is cost effective. The suboptimal efficacy and tolerability of IFN-based therapies, plus the significant economic burden, means the need for effective and well tolerated IFN-free anti-HCV therapy for pre- and post-LT remains high.


Assuntos
Antivirais/administração & dosagem , Doença Hepática Terminal/cirurgia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Transplante de Fígado , Ativação Viral/efeitos dos fármacos , Antivirais/efeitos adversos , Antivirais/economia , Análise Custo-Benefício , Esquema de Medicação , Custos de Medicamentos , Quimioterapia Combinada , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/economia , Doença Hepática Terminal/mortalidade , Doença Hepática Terminal/virologia , Hepacivirus/crescimento & desenvolvimento , Hepacivirus/imunologia , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/economia , Hepatite C Crônica/imunologia , Hepatite C Crônica/mortalidade , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/economia , Transplante de Fígado/mortalidade , Seleção de Pacientes , Recidiva , Fatores de Risco , Resultado do Tratamento
7.
Leuk Lymphoma ; 56(10): 2841-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25682966

RESUMO

Several reports have emphasized the risk of hepatitis B virus (HBV) reactivation in patients with lymphoproliferative disorders undergoing cytotoxic treatment. To determine the prevalence of occult B infection (OBI) in a population with chronic lymphocytic leukemia (CLL) and management with universal prophylaxis (UP) in all patients undergoing chemoimmunotherapy or targeted prophylaxis (TP) in patients experiencing seroreversion during therapy, we analyzed 397 patients with CLL from our database. The prevalence of OBI in our patients with CLL was 8.6% (34 patients). When comparing patients with OBI/CLL with those with CLL, we did not find any statistical difference among clinical-biological parameters and time dependent endpoints except for a lower peripheral blood lymphocyte count in the OBI/CLL group (p = 0.036). From 2000 to 2010 careful follow-up and TP were adopted; two out of 10 patients (20%) showed seroreversion. From June 2010 we adopted UP during and 12 months after immunosuppressive treatment in all patients with CLL with OBI; no evidence of seroreversion was detected.


Assuntos
Hepatite B/complicações , Hepatite B/epidemiologia , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores , Gerenciamento Clínico , Progressão da Doença , Feminino , Seguimentos , Hepatite B/diagnóstico , Hepatite B/terapia , Vírus da Hepatite B/fisiologia , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Resultado do Tratamento , Ativação Viral/efeitos dos fármacos
8.
J Clin Oncol ; 30(26): 3167-73, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22711851

RESUMO

PURPOSE: Hepatitis B virus (HBV) reactivation is a potentially fatal complication of chemotherapy that can be largely prevented with antiviral prophylaxis. It remains unclear whether HBV screening is cost effective. METHODS: A decision model was developed to compare the clinical outcomes, costs, and cost effectiveness of three HBV screening strategies for patients with lymphoma before R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy: screen all patients for hepatitis B surface antigen (HBsAg; Screen-All), screen patients identified as being at high risk for HBV infection (Screen-HR), and screen no one (Screen-None). Patients testing positive were administered antiviral therapy until 6 months after completion of chemotherapy. Those not screened were initiated on antiviral therapy only if HBV hepatitis occurred. Probabilities of HBV and lymphoma outcomes were derived from systematic literature review. A third-party payer perspective was adopted, costs were expressed in 2011 Canadian dollars, and a 1-year time horizon was used. RESULTS: Screen-All was the dominant strategy. It was least costly at $32,589, compared with $32,598 for Screen-HR and $32,657 for Screen-None. It was also associated with the highest 1-year survival rate at 84.99%, compared with 84.96% for Screen-HR and 84.86% for Screen-None. The analysis was sensitive to the prevalence of HBsAg positivity in the low-risk population, with Screen-HR becoming least costly when this value was ≤ 0.20%. CONCLUSION: In patients receiving R-CHOP for lymphoma, screening all patients for HBV reduces the rate of HBV reactivation (10-fold) and is less costly than screening only high-risk patients or screening no patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Análise Custo-Benefício , Diagnóstico Precoce , Hepatite B/diagnóstico , Hepatite B/economia , Linfoma Difuso de Grandes Células B/economia , Linfoma Difuso de Grandes Células B/virologia , Idoso , Anticorpos Monoclonais Murinos/efeitos adversos , Ciclofosfamida/efeitos adversos , Técnicas de Apoio para a Decisão , Doxorrubicina/efeitos adversos , Antígenos de Superfície da Hepatite B/análise , Vírus da Hepatite B , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Pessoa de Meia-Idade , Prednisona/efeitos adversos , Rituximab , Resultado do Tratamento , Vincristina/efeitos adversos , Ativação Viral/efeitos dos fármacos
9.
J Neurovirol ; 18(1): 55-61, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22281875

RESUMO

Polyomavirus JC (JCV) reactivation causing progressive multifocal leukoencephalopathy is a main concern during biological therapies. Here, JCV reactivation in patients suffering from immune-mediated diseases after a long-term treatment with anti-tumor necrosis factor alpha (TNF-α) inhibitor infliximab was investigated. Peripheral mononuclear blood cells (PBMC), plasma and urine samples were obtained from 61 immune-mediated diseases patients treated or not with infliximab in combination with steroid and other immunomodulators and from 20 healthy donors. JCV DNA was transiently detected in 12 PBMC of 40 patients at different doses of infliximab with a higher prevalence than that of the 21 patients untreated. Conversely, a stable JCV positivity in urine of treated and untreated patients was detected. Sequencing the noncoding control region (NCCR), all samples exhibited the archetype structure with few mutations in transcriptional factor binding regions. The consequence of anti-TNF-α treatment on viral persistence was examined monitoring Torquetenovirus viremia and investigating the TNF-α-induced microRNA regulators of transcriptional factors, with a binding site on NCCR. Although infliximab treatment in this study did not affect directly JCV reactivation, further investigation on host factor(s) regulated by it will be of warranty in the understanding the mechanism(s) that may affect viral persistence.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Vírus JC/genética , Leucócitos Mononucleares/virologia , Leucoencefalopatia Multifocal Progressiva/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Estudos de Casos e Controles , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/uso terapêutico , Infliximab , Vírus JC/patogenicidade , Leucócitos Mononucleares/imunologia , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/imunologia , Leucoencefalopatia Multifocal Progressiva/urina , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia , Ativação Viral/efeitos dos fármacos , Ativação Viral/imunologia
10.
Microb Ecol ; 56(3): 437-47, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18322729

RESUMO

Lysogeny has long been proposed as an important long-term maintenance strategy for autochthonous soil bacteriophages (phages). Whole genome sequence data indicate that prophage-derived sequences pervade prokaryotic genomes, but the connection between inferred prophage sequence and an active temperate phage is tenuous. Thus, definitive evidence of phage production from lysogenic prokaryotes will be critical in determining the presence and extent of temperate phage diversity existing as prophage within bacterial genomes and within environmental contexts such as soils. This study optimized methods for systematic and definitive determination of lysogeny within a collection of autochthonous soil bacteria. Twenty bacterial isolates from a range of Delaware soil environments (five from each soil) were treated with the inducing agents mitomycin C (MC) or UV light. Six isolates (30%) carried inducible temperate phages as evidenced by an increase in virus direct counts. The magnitude of induction response was highly dependent upon specific induction conditions, and corresponding burst sizes ranged from 1 to 176. Treatment with MC for 30 min yielded the largest induction responses for three of the six lysogens. Morphological analysis revealed that four of the lysogens produced lambda-like Siphoviridae particles, whereas two produced Myoviridae particles. Additionally, pulsed-field gel electrophoresis data indicated that two of the six lysogens were polylysogens, producing more than one distinct type of phage particle. These results suggest that lysogeny is relatively common among soil bacteria.


Assuntos
Bactérias/virologia , Bacteriófagos/fisiologia , Lisogenia/fisiologia , Microbiologia do Solo , Bactérias/genética , Bactérias/efeitos da radiação , Bacteriófagos/efeitos dos fármacos , Bacteriófagos/genética , Bacteriófagos/efeitos da radiação , Sequência de Bases , Contagem de Colônia Microbiana , DNA/química , DNA/genética , Eletroforese em Gel de Campo Pulsado , Lisogenia/efeitos dos fármacos , Lisogenia/efeitos da radiação , Microscopia Eletrônica de Transmissão , Mitomicina/farmacologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Ribossômico/química , RNA Ribossômico/genética , Análise de Sequência de DNA , Raios Ultravioleta , Ativação Viral/efeitos dos fármacos , Ativação Viral/fisiologia , Ativação Viral/efeitos da radiação
11.
Bone Marrow Transplant ; 29(3): 263-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11859400

RESUMO

HSV can cause oral lesions that exacerbate chemotherapy-related mucositis. Intravenous acyclovir is effective in preventing HSV reactivations, but expensive. Valacyclovir has good bioavailability and has not been studied for prophylaxis of HSV among PCT patients. We compared the efficacy and costs of valacyclovir in preventing HSV reactivation among HSV seropositive autologous progenitor cell transplantation (APCT) patients with historical controls in whom intravenous acyclovir or no HSV prophylaxis were used. Valacyclovir group: From October 1997 to April 1999 108 adult patients received valacyclovir 500 mg twice daily from day -3 of APCT until neutropenia recovery or day +30. Valacyclovir was switched to intravenous acyclovir in cases of oral intolerance (17 patients) or suspected HSV reactivation (five patients). Intravenous acyclovir group: From January 1996 to October 1997 43 patients received 5 mg/kg twice-daily intravenous acyclovir from day -3 until recovery from neutropenia. No prophylaxis group: 38 patients from January 1996 to October 1997 did not receive HSV prophylaxis. HSV reactivations were seen in 2.7%, 2% and 45% of patients in the valacyclovir, intravenous acyclovir, and no prophylaxis groups, respectively. Valacyclovir was well tolerated and was the least expensive strategy. Oral valacyclovir was as effective as intravenous acyclovir for the prophylaxis of HSV reactivation in APCT patients.


Assuntos
Aciclovir/análogos & derivados , Aciclovir/administração & dosagem , Antivirais/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpes Simples/prevenção & controle , Simplexvirus/efeitos dos fármacos , Valina/análogos & derivados , Valina/administração & dosagem , Aciclovir/economia , Aciclovir/normas , Adolescente , Adulto , Idoso , Antivirais/economia , Antivirais/normas , Custos e Análise de Custo , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Herpes Simples/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Simplexvirus/crescimento & desenvolvimento , Transplante Autólogo/efeitos adversos , Transplante Autólogo/métodos , Resultado do Tratamento , Valaciclovir , Valina/economia , Valina/normas , Ativação Viral/efeitos dos fármacos
12.
Mutat Res ; 490(2): 141-58, 2001 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-11342240

RESUMO

The genotoxicity of river water and sediment including interstitial water was evaluated by microscreen phage-induction and Salmonella/microsome assays. Different processes used to fractionate the sediment sample were compared using solvents with different polarities. The results obtained for mutagenic activity using the Salmonella/microsome test were negative in the water and interstitial water samples analysed using the direct concentration method. The responses in the microscreen phage-induction assay showed the presence of genotoxic or indicative genotoxic activity for at least one water sample of each site analysed using the same concentration method. Similar results were obtained for interstitial water samples, i.e. absence of mutagenic activity in the Salmonella/microsome test and presence of genotoxic activity in the microscreen phage-induction assay. Metal contamination, as evidenced by the concentrations in stream sediments, may also help explain some of these genotoxic results. Stream sediment organic extracts showed frameshift mutagenic activity in the ether extract detected by Salmonella/microsome assay. The concentrates evaluated by microscreen phage-induction assay identified the action of organic compounds in the non-polar, medium polar and polar fractions. Thus, the microscreen phage-induction assay has proven to be a more appropriate methodology than the Salmonella/microsome test to analyse multiple pollutants in this ecosystem where both organic compounds and heavy metals are present.


Assuntos
Bacteriófago lambda/fisiologia , DNA Bacteriano/efeitos dos fármacos , Metais Pesados/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Ativação Viral/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise , Animais , Bacteriófago lambda/genética , Biotransformação , Brasil , DNA Bacteriano/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/virologia , Água Doce , Genes Bacterianos/efeitos dos fármacos , Sedimentos Geológicos/química , Resíduos Industriais/análise , Lisogenia , Masculino , Metais Pesados/análise , Metais Pesados/isolamento & purificação , Microssomos Hepáticos/metabolismo , Testes de Mutagenicidade , Ratos , Ratos Sprague-Dawley , Resposta SOS em Genética , Salmonella typhimurium/genética , Solventes , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
13.
J Clin Pathol ; 53(6): 470-5, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10911807

RESUMO

AIMS: To determine the conditions of photodynamic inactivation of vesicular stomatitis virus (VSV) added to pooled coumarin plasma and the effects of the photodynamic treatment on the prothrombin times and international normalised ratio (INR) in a Netherlands national external quality assessment scheme. METHODS: Pooled coumarin plasma samples were illuminated with visible light in the presence of 1 microM methylene blue. Inactivation conditions for VSV in pooled coumarin plasma were determined using an end point dilution assay. Plasma illuminated for 20 minutes was mixed with red blood cells and mailed to participants of the Netherlands external quality assessment (EQA) scheme. Prothrombin times and INRs were determined with various thromboplastin reagents. RESULTS: Photodynamic treatment using 1 microM methylene blue and 700 W/m2 caused 4.7 log inactivation of VSV in pooled coumarin plasma. Fibrinogen and coagulation factors II, V, VII, and X were decreased slightly by the treatment. These conditions caused prolongation of the prothrombin time in EQA surveys. The magnitude of the effect was different for various thromboplastin reagents. The increase of the INR was negligible when measured with the Thrombotest reagent. With other reagents, an approximately 5-16% increase of the INR was observed. Interlaboratory variation of the INR was not affected by photodynamic treatment. CONCLUSIONS: Photodynamic treatment of pooled coumarin plasma is very effective for the inactivation of some enveloped viruses such as VSV, but has only a limited effect on the prothrombin time and INR. Photodynamic treatment can be used to improve the viral safety of coumarin plasma for EQA of the prothrombin time and INR.


Assuntos
Cumarínicos/sangue , Coeficiente Internacional Normatizado/normas , Fotoquimioterapia , Tempo de Protrombina , Vírus da Estomatite Vesicular Indiana/efeitos dos fármacos , Humanos , Técnicas de Diluição do Indicador , Azul de Metileno/farmacologia , Garantia da Qualidade dos Cuidados de Saúde , Infecções por Rhabdoviridae/prevenção & controle , Ativação Viral/efeitos dos fármacos
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