High frequency of Lamivudine and Telbivudine resistance mutations in hepatitis B virus isolates from human immunodeficiency virus co-infected patients on highly active antiretroviral therapy in Bucaramanga, Colombia.

Hepatitis B virus (HBV) antiviral Resistance-Associated Mutations (RAMs) in human immunodeficiency virus (HIV) coinfected patients undergoing highly active antiretroviral therapy (HAART) are complex and incompletely understood. We aimed to determine the prevalence of HBV coinfection, HBV genotypes, and RAMs in a cohort of people living with HIV (PLWH) in the northeastern region of Colombia. This cross-sectional study was carried out between February 2013 and February 2014. Virological, immunological and HAART data were collected from clinical records. In-house nested PCR and Sanger sequencing of the HBV pol gene were used to identify coinfections, genotypes, RAMs and HBV s antigen (HBsAg) escape mutants. Among 275 PLWH, HBV coinfection was confirmed in 32 patients (11.6%), of whom nine (28.2%) were HBsAg positive (active hepatitis B), and 23 (71.8%) were occult hepatitis B infections (OBI). All HBV sequences (n = 23) belonged to the genotype F3. Among HIV/HBV coinfections, 71.9% had CD4+ T cell counts above 200 cells/mm3 and 37.5% had undetectable HIV viral loads. The RAMs rtL80I, rtL180M, and rtM204V, which confer resistance to Lamivudine/Telbivudine and partially resistant to Entecavir, were found in all HBV isolates. An unknown rt236Y mutation to Tenofovir was also identified. Most patients under HAART received first-generation HBV antiviral therapy with a low genetic barrier to resistance. Antiviral Drug-associated Potential Vaccine-escape Mutations (ADAPVEMs) in the S gene were observed in all isolates ranging from 1-20 amino acid substitutions. However, no vaccine escape mutants were detected. In Conclusion, these findings highlight the importance of HBV molecular screening, antiviral resistance monitoring and new guidelines for PLWH to overcome RAMs and prevent HBV-related liver disease.

The effects of genetic polymorphisms on benzene-exposed workers: A systematic review.

BACKGROUND AND AIMS: Benzene is a group I carcinogen, which has been associated with leukemia and myelodysplastic syndrome. Moreover, it has been proposed that polymorphisms in benzene metabolizing genes influence the outcomes of benzene exposure in the human body. This systematic review aims to elucidate the existent relationship between genetic polymorphisms and the risk of developing adverse health effects in benzene-exposed workers. METHODS: Three databases were systematically searched until April 2020. The preferred reporting items for systematic reviews and meta-analyses method was used to select articles published between 2005 and 2020. Quality assessment and risk of bias were evaluated by the Newcastle-Ottawa scale. RESULTS: After full-text evaluation, 36 articles remained out of 645 initially screened. The most studied health effects within the reviewed papers were chronic benzene poisoning, hematotoxicity, altered urinary biomarkers of exposure, micronucleus/chromosomal aberrations, and gene methylation. Furthermore, some polymorphisms on NQO1, GSTT1, GSTM1, MPO, and CYP2E1, among other genes, showed a statistically significant relationship with an increased risk of developing at least one of these effects on benzene-exposed workers. However, there was no consensus among the reviewed papers on which specific polymorphisms were the ones associated with the adverse health-related outcomes, except for the NQO1 rs1800566 and the GSTT1 null genotypes. Additionally, the smoking habit was identified as a confounder, demonstrating worse health outcomes in exposed workers that smoked. CONCLUSION: Though there is a positive relationship between genetic polymorphisms and detrimental health outcomes for benzene-exposed workers, broader benzene-exposed cohorts that take into account the genetic diversity of the population are needed in order to determine which specific polymorphisms incur in health risks.

A novel method for isolation and culture of primary swine gastric epithelial cells.

BACKGROUND: Culturing primary epithelial cells has a major advantage over tumor-derived or immortalized cell lines as long as their functional phenotype and genetic makeup are mainly maintained. The swine model has shown to be helpful and reliable when used as a surrogate model for human diseases. Several porcine cell lines have been established based on a variety of tissues, which have shown to extensively contribute to the current understanding of several pathologies, especially cancer. However, protocols for the isolation and culture of swine gastric epithelial cells that preserve cell phenotype are rather limited. We aimed to develop a new method for establishing a primary epithelial cell culture from the fundic gland region of the pig stomach. RESULTS: Mechanical and enzymatic dissociation of gastric tissue was possible by combining collagenase type I and dispase II, protease inhibitors and antioxidants, which allowed the isolation of epithelial cells from the porcine fundic glands showing cell viability > 90% during the incubation period. Gastric epithelial cells cultured in RPMI 1640, DMEM-HG and DMEM/F12 media did not contribute enough to cell adhesion, cluster formation and cell proliferation. By contrast, William's E medium supplemented with growth factors supports confluency and proliferation of a pure epithelial cell monolayer after 10 days of incubation at 37 °C, 5% CO2. Mucin-producing cell phenotype of primary isolates was confirmed by PAS staining, MUC1 by immunohistochemistry, as well as the expression of MUC1 and MUC20 genes by RT-PCR and cDNA sequencing. Swine gastric epithelial cells also showed origin-specific markers such as cytokeratin cocktail (AE1/AE3) and cytokeratin 18 (CK-18) using immunohistochemical and immunofluorescence methods, respectively. CONCLUSIONS: A new method was successfully established for the isolation of primary gastric epithelial cells from the fundic gland zone through a swine model based on a combination of tissue-specific proteases, protease inhibitors and antioxidants after mechanical cell dissociation. The formulation of William's E medium with growth factors for epithelial cells contributes to cell adhesion and preserves functional primary cells phenotype, which is confirmed by mucin production and expression of typical epithelial markers over time.

Epidemiology, risk factors and genotypes of HBV in HIV-infected patients in the northeast region of Colombia: high prevalence of occult hepatitis B and F3 subgenotype dominance.

INTRODUCTION: Chronic hepatitis B virus (HBV) infection is an increasing cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected individuals. HIV-positive patients are commonly co-infected with HBV due to shared routes of transmission. OBJECTIVES: Our aim was to determine the risk factors, prevalence, genotypes, and mutations of the Surface S gene of HBV, and occult hepatitis B infection (OBI) among patients infected with HIV in a northeastern Colombian city. METHODS: A cross-sectional study was conducted with 275 HIV-positive patients attending an outpatient clinic in Bucaramanga, Colombia during 2009-2010. Blood samples were collected and screened for serological markers of HBV (anti-HBs, anti-HBc and HBsAg) through ELISA assay. Regardless of their serological profile, all samples were tested for the HBV S gene by nested-PCR and HBV genotypes were determined by phylogenetic inference. Clinical records were used to examine demographic, clinical, virological, immunological and antiretroviral therapy (ART) variables of HIV infection. RESULTS: Participants were on average 37±11 years old and 65.1% male. The prevalence of HIV-HBV coinfection was 12% (95%CI 8.4-16.4) of which 3.3% had active HBV infection and 8.7% OBI. The prevalence of HIV-HBV coinfection was associated with AIDS stage and ART treatment. Sequence analysis identified genotype F, subgenotype F3 in 93.8% of patients and genotype A in 6.2% of patients. A C149R mutation, which may have resulted from failure in HBsAg detection, was found in one patient with OBI. CONCLUSIONS: The present study found a high prevalence of HIV-HBV coinfection with an incidence of OBI 2.6-fold higher compared to active HBV infection. These findings suggest including HBV DNA testing to detect OBI in addition to screening for HBV serological markers in HIV patients.

Marcadores serológicos y moleculares de infección por el virus de la hepatitis B en estudiantes universitarios colombianos / Serological and molecular markers for Hepatitis B virus in university students

Introducción: Reportes de la OMS demuestran que la carga de infección por el virus de la hepatitis B (VHB) varía de acuerdo con la región geográfica y el grupo de riesgo. Propósito: Determinar la prevalencia de infección por el VHB y el estatus de vacunación en estudiantes universitarios de Bucaramanga. Metodología: Estudio descriptivo de corte transversal realizado en el 2010. Se incluyeron 1.298 estudiantes de cinco universidades. Se identificaron marcadores serológicos de infección para el VHB por ELISA y el genoma viral se detectó mediante PCR anidado. Resultados: Se estableció infección activa en 0,15%, confirmada por PCR; infección resuelta a 0,60%; 1,1% anti-HBc aislado, 30,2% vacunados y 67,9% susceptibles. No se evidenció hepatitis B oculta. Conclusiones: La baja prevalencia de infección por el virus de la hepatitis B reportada en el presente estudio contrasta con el patrón epidemiológico intermedio descrito en la región. Se encontró una baja cobertura de vacunación y ausencia de hepatitis B oculta en los estudiantes universitarios.

Introduction: Reports from the World Health Organization (WHO) show that the prevalence of hepatitis B virus (HBV) infections varies by geographical region and risk group. Purpose: The purpose of this study was to determine the prevalence of HBV infections, as well as the vaccination status, among university students from Bucaramanga. Methodology: This was a cross sectional study conducted in 2010 which included 1298 students from five universities. Serological markers for HBV infection were detected using ELISA. Viral genomes were detected with nested polymerase chain reaction (PCR). Results: Active infections were established in 0.15% of the study population, and this finding was confirmed by PCR. Resolved infections were identified in 0.60% of the population. Isolated anti-HBc antibodies were found, 30.2% of vaccinated individuals. 67.9% of the study population was susceptible. No occult HBV was detected. Conclusions: The low prevalence of HBV infections reported in this study contrasts with the intermediate epidemiological pattern described in the region. We found poor vaccination coverage and absence of occult hepatitis B among these university students.

Ausencia de infección por virus de la hepatitis C en usuarios de drogas ilícitas en la ciudad de Bucaramanga, Colombia / Absence of hepatitis C infection among illegal drug users in Bucaramanga, Colombia

Nos propusimos estimar la prevalencia y factores de riesgo asociados con la transmisión del virus de la hepatitis C (VHC) en usuarios de drogas ilícitas. Estudio descriptivo realizado en tres centros de rehabilitación y una cárcel en el 2009. Mediante entrevista se recolectó información sociodemográfica y factores de riesgo en 259 participantes. Anticuerpos anti-VHC fueron investigados en suero utilizando dos inmunoensayos. La prevalencia de VHC fue del 0%. El 98% usa drogas ilícitas por vía oral o nasal y 4,2% intravenosa. El 78% consume marihuana, 51% bazuco, 50,2% cocaína y 22,8% anfetaminas. El 59% ha consumido drogas por más de 5 años, 60,2% usa tatuajes, 17,8% piercings y 84,9% practica relaciones sexuales sin preservativo. La prevalencia de infección por VHC fue inferior a la descrita en Latinoamérica en usuarios de drogas. Se identificaron factores de riesgo que facilitarían la infección por el virus una vez sea introducido en esta población.

The aim of this study was to estimate the prevalence of hepatitis C virus (HCV) and identify risk factors associated with the transmission this virus among drug users. In 2009 we performed a cross-sectional study at three facilities handling cases of drug addiction and in one prison. 259 participants were interviewed to collect socio-demographic information and determine risk factors. Anti-HCV antibodies were identified with two different immunoassays. HCV prevalence was 0%. 98% of participants used illegal drugs either orally or nasally while 4.2% injected drugs. 78% of participants reported marijuana consumption, 51% reported consumption of bazuco (Colombian variant of crack cocaine), 50.2% reported cocaine consumption and 22.8% reported amphetamine consumption. 59% had consumed drugs for more than 5 years, 60.2% had tattoos, 17.8% had piercings, and 84.9% have practiced unsafe sex. HCV prevalence was lower than reported in previous studies of drug users in Latin-America. However, we identified risk factors that would facilitate HCV infection once the virus is introduced in this population.