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. 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. 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. 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. 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.

PROPOSAL TO SELECT ESSENTIAL OILS FROM COLOMBIAN PLANTS FOR RESEARCH BASED ON ITS CYTOXICITY

Despite intense research efforts, no approved effective therapies are available for dengue treatment. Standardized plant extracts could serve as potential candidates for developing plant-based treatments for dengue. We have compared the anti-dengue potential of ethanolic (EtOH) and supercritical (SCO2) extracts of Lippia origanoides Kunth (Verbenacea). The mode of antiviral action and the effect on the release of IL-β from DENV-1-stimulated macrophages (PMA/THP-1) were evaluated. In silico analyses were performed to predict molecular interactions between flavonoids identified in the UHPLC–ESI+–Orbitrap–MS analysis and target proteins. The EtOH extract showed a strong antiviral effect (IC50, 22 and 17 µg/mL; SI, 20 and 23) before and during DENV-1 adsorption to liver (HepG-2) cells. SCO2 showed a weak antiviral effect. EtOH, but not SCO2, reduced the level of IL-1β released from PMA/THP-1 cells by 45-55%. Flavonoid glycosides were identified in EtOH but not in SCO2. Seventeen flavonoids were predicted to bind to DENV E, GRP78, CLEC5A, and NLRP3 proteins involved in DENV replication and IL-1β production. The data provide a first step towards defining the potential of L. origanoides extract as a candidate for developing phytotherapeutics for dengue.

The lack of effective conventional therapies against dengue has created an interest in herbal preparations as alternative therapies. In the present study, in vitroeffects of Cordia curassavicaessential oil (EO) on both dengue virus replication and cytokine production were examined. Predictions ofmolecular interactions between EO compounds and virus and cell proteins were performed with AutoDock Vina. The EO inhibited replication of dengue virus serotypes at IC50< 30 μg/mL, and it reduced 87% TNF-α, 67% IL-8 and 46% IFN-α in LPS-stimulated PBMCs.The main EO compounds were trans-β-caryophyllene (21.4%), germacrene D (17.8%), α-copaene (16.5%), trans-β-guaiene (8.2%), and α-pinene (6.0%). The first two compounds, δ-cadinene, α-muurolene, α-cubebene and β-burbonene were coupled to proteins involved in the TLR-4 cytokine effector pathway. 3,7-Guaiadiene was coupled to the viral E and C proteins. This study demonstrates the potential of C. curassavicaEO as a starting point for discovering novel therapeutic for dengue.

The poultry industry is continually seeking efficient, practical strategies to control infectious diseases. Among these new alternatives are essential oils (EOs), naturally occurring compounds with antimicrobial properties. Their effectiveness has been demonstrated in various studies that focus on their broad antiviral properties. The present experiment evaluated the antiviral efficacy of an EOs formulation against the H7N3 subtype of avian influenza virus (AIV) by directly mixing virus and EOs (virus/EOs mixture) through an in vitro model in cultured Madin-Darby canine kidney cells (MDCKs). The experiment used a focus reduction neutralization test (FRNT) to determine the 50% inhibitory concentration (IC₅₀) by virus/EOs mixture, as well as the application of EOs 24 h before infection, through a viral inhibition test using a chicken embryo (CE) in ovo model. The results demonstrated the antiviral activity of the EOs formulation against the H7N3 in vitro model (IC₅₀ values of 20.4 and 38.3 ppm and selective index (SI) values of 9.4 and 5.1) and in ovo model (decreasing hemagglutination titers to 1 HA unit, 10^5.28 embryo infectious dose 50% (EID₅₀) per mL, and viral loads to approximately 10^11.4 copies/mL) when applied in CE, 24 h before viral infection, representing the lowest replication indicators recorded during the experiment. According to the results, the EOs formulation demonstrated antiviral activity against AIV H7N3 both as a virus/EOs mixture and through application in ovo 24 h before infection. Application 24 h before infection in CE showed a significant effect compared with the virus/EOs mixture, demonstrating an antiviral effect in the ovo infection model. This study demonstrates both the virucidal and antiviral capacity of the compounds in the EOs formulation against AIV H7N3 and their efficacy when applied 24 h before infection in the in ovo model.

This study examined the relationship between flavonoid content and the antiviral effects of plant extracts against the dengue virus (DENV). Fourteen extracts from medicinal plants cultivated in Colombia, which were prepared by ultrasonic-assisted solvent extraction (UAE) and supercritical fluid extraction (SFE) were included. UHPLC/ESI-Q-Orbitrap-MS analysis identified forty-six flavonoids. Antiviral effect on viral adsorption was evaluated using the DENV-CPE-based assay. UAE extracts of Scutellaria coccinea, Scutellaria incarnata, and Lippia alba contained higher amounts of flavonoid glycosides (from 97.0% to 87.9%) than aglycones, and showed antiviral effect (IC₅₀: 3.0 to 65 µg/mL; SI: 0.4 to 71). In contrast, UAE and SFE extracts from Lippia origanoides had higher content of flavonoid aglycones (41.7% to 93.4%) than glycosides (0.0 to 58.3%) and showed no antiviral effect. Cluster and one-way ANOVA analyses revealed a positive correlation between increased levels of flavone glycosides in the extract and a strong antiviral effect. Docking analyses (AutoDock Vina) revealed that the flavonoid glycosides exhibited a higher binding affinity for the target proteins (E, Gas6-Axl, clathrin, and dynamin) than the aglycones did. This study establishes a scientific basis for using extracts rich in flavonoid glycosides, particularly flavones, as starting points for developing plant-based therapies to treat dengue.