Virus del dengue de serotipo 1 (DENV-1) de Colombia: su contribución a la presentación del dengue en el departamento de Santander

Introduction: Between 1998 and 2008 all dengue virus serotypes circulated in the Departamento de Santander, an endemic region in northeastern Colombia. No information is available as to the role of serotype 1 (DENV-1) with respect to epidemiology of dengue.Objective: To analyze the relationship between changes in DENV-1 predominance with respect to genetic diversity, prevalence of others serotypes and occurrence of severe dengue.Methods: Virus genetic diversity was studied by phylogenetic analysis comparing E gene sequences from 12 viral strains. Data about serotypes predominance obtained in previous studies and official data about dengue incidence were used for analysis.Results: Selected viruses grouped into genotype V together DENV-1 from Latin America countries, and segregation in four lineages was evidenced. Changes in virus predominance coincided with replacement of lineage, increase in prevalence of DENV-2 and DENV-3 and increase of severe dengue.Conclusion: Genetic divergence could have contributed to changes in DENV-1 predominance. The relationship of the virus with DENV-2 and DENV-3 could create scenarios that promote occurrence of severe cases. More studies are required to ascertain the precise role of serotypes in the epidemiology of dengue. doi: http://dx.doi.org/10.7705/biomedica.v33i0.717Introducción. Los cuatro serotipos del virus del dengue circularon en el departamento de Santander entre 1998 y 2008. No existe información sobre el papel del serotipo 1 (DENV-1) en la epidemiología de la enfermedad.Objetivo. Analizar la relación entre el cambio de predominancia del (DENV-1) con su diversificación genética, predominancia de los otros serotipos y presentación del dengue grave.Materiales y métodos. La diversificación genética se estudió por análisis filogenético usando la secuencia del gen E de 12 cepas del virus. Para el análisis se utilizaron datos sobre predominancia delos serotipos obtenidos en estudios previos y datos oficiales de incidencia del dengue.Resultados. Los virus seleccionados se agruparon en el genotipo V junto a (DENV-1) de países de Latinoamérica y se evidenció segregación en cuatro linajes. Los cambios en la predominancia del virus coincidieron con el reemplazo de linaje y esto, a su vez, con incremento en la prevalencia de DENV-2y DENV-3, e incremento del dengue grave.Conclusión. La diversificación genética podría contribuir a cambios de predominancia de (DENV-1), y la relación del virus con el DENV-2 y DENV-3 en situaciones que favorecen la presentación de casos graves. Se necesitan más estudios para precisar el papel de los serotipos en la epidemiología del dengue.doi: http://dx.doi.org/10.7705/biomedica.v33i0.717

A phylogenetic analysis using full-length viral genomes of South American dengue serotype 3 in consecutive Venezuelan outbreaks reveals a novel NS5 mutation

Dengue virus currently causes 50–100 million infections annually. Comprehensive knowledge about the evolution of Dengue in response to selection pressure is currently unavailable, but would greatly enhance vaccine design efforts. In the current study, we sequenced 187 new dengue virus serotype 3 (DENV-3) genotype III whole genomes isolated from Asia and the Americas. We analyzed them together with previously-sequenced isolates to gain a more detailed understanding of the evolutionary adaptations existing in this prevalent American serotype. In order to analyze the phylogenetic dynamics of DENV-3 during outbreak periods; we incorporated datasets of 48 and 11 sequences spanning two major outbreaks in Venezuela during 2001 and 2007–2008, respectively. Our phylogenetic analysis of newly sequenced viruses shows that subsets of genomes cluster primarily by geographic location, and secondarily by time of virus isolation. DENV-3 genotype III sequences from Asia are significantly divergent from those from the Americas due to their geographical separation and subsequent speciation. We measured amino acid variation for the E protein by calculating the Shannon entropy at each position between Asian and American genomes. We found a cluster of seven amino acid substitutions having high variability within E protein domain III, which has previously been implicated in serotype-specific neutralization escape mutants. No novel mutations were found in the E protein of sequences isolated during either Venezuelan outbreak. Shannon entropy analysis of the NS5 polymerase mature protein revealed that a G374E mutation, in a region that contributes to interferon resistance in other flaviviruses by interfering with JAK-STAT signaling was present in both the Asian and American sequences from the 2007–2008 Venezuelan outbreak, but was absent in the sequences from the 2001 Venezuelan outbreak. In addition to E, several NS5 amino acid changes were unique to the 2007–2008 epidemic in Venezuela and may give additional insight into the adaptive response of DENV-3 at the population level

Aloysia citriodora Palau

Aloysia citriodora Palau, cedron or lemon verbena, is a South American aromatic species widespread in North America, Eurasia, and Africa. It is appreciated because it therapeutic and food (condiment, flavoring) uses. Also is valued as ornamental, insect repellent, and sometimes in perfumery. Its popular culinary and medicinal uses have been expanded from Latin America to the rest of the Western world. Its main active constituents are essential oils, to which owes its aroma and flavor similar to lemon, but also contain flavonoids, verbascosides, iridoids heterosides, and others. It most disseminated uses in folk medicine include those to treat gastrointestinal disorders (digestive, antispasmodic, carminative, antidiarrheal), mild sedative, cardiotonic, febrifuge, analgesic, and antiseptic. Various experimental studies validate different effects, as eupeptic, spasmolytic, antimicrobial, anti-inflammatory, analgesic, hypotensive, among others. Its sedative/anxiolytic activity requires deeper further studies. Of particular interest are its cancer-related effects analyzed to date (antimutagenic, antigenotoxic, and antiangiogenic), and its antioxidant activity linked in various ways to our health.Fil: Hurrell, Julio Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Etnobotánica y Botánica Aplicada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin