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2.
Am J Trop Med Hyg ; 103(1): 38-40, 2020 07.
Article in English | MEDLINE | ID: mdl-32228776

ABSTRACT

In the most recent Brazilian yellow fever (YF) outbreak, a group of clinicians and researchers initiated in mid-January 2018 a considerable effort to develop a multicenter randomized controlled clinical trial to evaluate the effect of sofosbuvir on YF viremia and clinical outcomes (Brazilian Clinical Trials Registry: RBR-93dp9n). The approval of this protocol had urgency given the seasonal/short-lived pattern of YF transmission, large number of human cases, and epidemic transmission at the outskirts of a large urban center. However, many intricacies in the research regulatory and ethical submission systems in Brazil were indomitable even under such pressing conditions. By April 2018, we had enrolled 29 patients for a target sample size of 90 participants. Had enrollment been initiated 3 weeks earlier, an additional 31 patients could have been enrolled, reaching the prespecified sample size for the interim analysis. This recent experience highlights the urgent need to improve local preparedness for research in the setting of explosive outbreaks, as has been seen in the last few years in different countries.


Subject(s)
Biomedical Research/legislation & jurisprudence , Communicable Diseases, Emerging/epidemiology , Disease Outbreaks , Randomized Controlled Trials as Topic/legislation & jurisprudence , Viremia/epidemiology , Yellow Fever/epidemiology , Yellow fever virus/pathogenicity , Aedes/virology , Animals , Antiviral Agents/therapeutic use , Biomedical Research/ethics , Brazil/epidemiology , Communicable Diseases, Emerging/drug therapy , Communicable Diseases, Emerging/virology , Government Regulation , Hospitalization/statistics & numerical data , Humans , Mosquito Vectors/virology , Patient Selection/ethics , Randomized Controlled Trials as Topic/ethics , Sofosbuvir/therapeutic use , Viremia/drug therapy , Yellow Fever/drug therapy , Yellow Fever/virology , Yellow fever virus/drug effects , Yellow fever virus/physiology
3.
Med Microbiol Immunol ; 205(2): 111-7, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26272127

ABSTRACT

Hepatitis C virus (HCV) infection affects approximately 3 % of the world population. HCV targets hepatic tissue, and most infected patients develop a chronic infection. Currently, studies have demonstrated an association between HCV-RNA replication and miR-122, the most abundant microRNA in the liver. Our aim was to evaluate liver and serum expression of miR-122 in patients infected with HCV genotypes 1 and 3, and to identify possible associations between miR-122 expression and lipid profiles, HCV viral load, apolipoproteins and liver enzymes. MicroRNAs were isolated from blood and liver tissue, and miR-122 expression was quantified by real-time PCR. HCV viral load was quantified by real-time PCR and HCV genotype, and serum biomarkers were obtained from medical report. The levels of miR-122 were higher in liver than those in blood from individuals infected with HCV genotypes 1 and 3 (p < 0.0001). The tissue levels of miR-122 were higher in subjects infected with HCV genotype 3 (6.22-fold, p < 0.001). A positive correlation was observed between the blood and hepatic levels of miR-122 in patients infected with HCV genotype 1 (r = 0.302, p = 0.026); in these patients, an inverse correlation was observed between serum apolipoprotein A-II (ApoA-II) levels and the blood (r = -0.330; p = 0.014) and hepatic (r = -0.311; p = 0.020) levels of miR-122. In patients infected with HCV genotype 3, there was a positive correlation between the hepatic miR-122 and the high-density lipoprotein-HDL (r = 0.412, p = 0.036) and insulin (r = 0.478, p = 0.044). Lipid metabolism proteins and miR-122 expression levels have different relations in HCV-3- and HCV-1-infected patients.


Subject(s)
Gene Expression Regulation , Genotype , Hepacivirus/genetics , Hepatitis C/genetics , Hepatitis C/virology , Liver/metabolism , Liver/virology , MicroRNAs/genetics , Adult , Biomarkers , Biopsy , Female , Hepatitis C/metabolism , Hepatitis C, Chronic/genetics , Hepatitis C, Chronic/metabolism , Hepatitis C, Chronic/virology , Humans , Lipid Metabolism , Liver/pathology , Liver Cirrhosis/etiology , Liver Cirrhosis/pathology , Liver Function Tests , Male , MicroRNAs/blood , Middle Aged , Viral Load
4.
Antivir Ther ; 20(4): 387-95, 2015.
Article in English | MEDLINE | ID: mdl-25624410

ABSTRACT

BACKGROUND: Nucleoside/nucleotide analogue (NA) treatment causes selection pressure for HBV strains carrying mutations conferring NA resistance. Drug-resistance mutations occur in the reverse transcriptase (RT) region of the HBV polymerase gene and spontaneously arise during viral replication. These mutations can also alter the hepatitis B surface (HBs) protein and in some cases reduce binding to HBs antibodies. The spread of NA-resistant HBV may impact the efficacy of antiviral treatment and hepatitis B immunization programmes. In this study, we used direct sequencing to assess the occurrence of HBV carrying known mutations that confer NA resistance in the largest cohort of treatment-naive patients with chronic hepatitis B (CHB) to date. METHODS: HBV DNA samples isolated from 702 patients were sequenced and the RT region subjected to mutational analysis. RESULTS: There was high genetic variability among the HBV samples analysed: A1 (63.7%), D3 (14.5%), A2 (3.3%), A3 (0.1%), B1 (0.1%), B2 (0.1%), C2 (0.9%), D1 (0.9%), D2 (4.6%), D4 (5.1%), D unclassified subgenotype (0.7%), E (0.6%), F2a (4.6%), F4 (0.4%) and G (0.4%). HBV strains harbouring mutations conferring NA resistance alone or combined with compensatory mutations were identified in 1.6% (11/702) of the patients. CONCLUSIONS: HBV strains harbouring resistance mutations can comprise the major population of HBV quasispecies in treatment-naive patients. In Brazil, there is a very low frequency of untreated patients who are infected with these strains. These findings suggest that the spread and natural selection of drug-resistant HBV is an uncommon event and/or most of these strains remain unstable in the absence of NA selective pressure.


Subject(s)
Antiviral Agents/pharmacology , Drug Resistance, Viral/genetics , Gene Products, pol/genetics , Hepatitis B virus/drug effects , Hepatitis B, Chronic/virology , Mutation , Adenine/analogs & derivatives , Adenine/pharmacology , Antibodies, Viral/genetics , Antibodies, Viral/immunology , Brazil , DNA, Viral/genetics , DNA, Viral/immunology , Gene Products, pol/antagonists & inhibitors , Gene Products, pol/metabolism , Genotype , Guanine/analogs & derivatives , Guanine/pharmacology , Hepatitis B Surface Antigens/genetics , Hepatitis B Surface Antigens/immunology , Hepatitis B virus/genetics , Hepatitis B virus/immunology , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/immunology , Humans , Lamivudine/pharmacology , Microbial Sensitivity Tests , Organophosphonates/pharmacology , Retrospective Studies , Sequence Analysis, DNA , Tenofovir/pharmacology , Virus Replication/drug effects
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