Evolutionary history and spatio-temporal dynamics of dengue virus serotypes in an endemic region of Colombia.

Dengue is a prevalent disease in Colombia and all dengue virus serotypes (DENV-1 to -4) co-circulate in the country since 2001. However, the relative impact of gene flow and local diversification on epidemic dynamics is unknown due to heterogeneous sampling and lack of sufficient genetic data. The region of Santander is one of the areas with the highest incidence of dengue in Colombia. To provide a better understanding of the epidemiology of dengue, we inferred DENV population dynamics using samples collected between 1998 and 2015. We used Bayesian phylogenetic analysis and included 143 new envelope gene sequences from Colombia, mainly from the region of Santander, and 235 published sequences from representative countries in the Americas. We documented one single genotype for each serotype but multiple introductions. Whereas the majority of DENV-1, DENV-2, and DENV-4 strains fell into one single lineage, DENV-3 strains fell into two distinct lineages that co-circulated. The inferred times to the most recent common ancestors for the most recent clades of DENV-1, DENV-2, and DENV-4 fell between 1977 and 1987, and for DENV-3 was around 1995. Demographic reconstructions suggested a gradual increase in viral diversity over time. A phylogeographical analysis underscored that Colombia mainly receives viral lineages and a significant diffusion route between Colombia and Venezuela. Our findings contribute to a better understanding of the viral diversity and dengue epidemiology in Colombia.

Leucemia mieloide cronica, estado del arte / Myeloid cronic leukemia, state of the art

La leucemia mieloide crónica es un desorden clonal maligno producido por la translocación genética t(9;22)(q34;q11), que genera hiperplasia en médula ósea y proliferación incontrolada de la línea mieloide en sangre periférica. Hasta 1980, se consideró una enfermedad fatal, sin embargo gracias a los avances científicos se empezaron a dilucidar diferentes estrategias terapéuticas, que han ido desde el trasplante alogénico de médula ósea, hasta el desarrollo de fármacos de última generación como es el caso de los inhibidores tirosin kinasa de primera y segunda generación (Imanitib y Nilotinib), con los cuales se ha obtenido una respuesta positiva hasta en un 95% de los casos que ha obligado a nuevas estrategias diagnósticas y de seguimiento como la fluorescencia por hibridación in situ y las diferentes variantes de la reacción en cadena de la polimerasa; conocer estos avances es fundamental para nuestro desempeños como profesionales de la salud, ya que nos permite actuar y tomar decisiones acertadas para el beneficio del paciente, acordes con los recursos del medio.

Myeloid chronic leukemia is a malignant clonal disorder caused by genetic the translocation t(9; 22) (q34, q11) which generates hyperplasia in bone marrow and uncontrolled myeloid proliferation in peripheral blood. Until 1980, it was considered a fatal disease, however, thanks to scientific progress, scientists began to elucidate different therapeutic strategies, from allogeneic transplantation of bone marrow, to the first and second generation tyrosine kinase inhibitors (Imanitib and Nilotinib), which has provided a positive response in up to 95% of cases. Such development has enforced new diagnostic and monitoring strategies as the fluorescence in situ hybridization and different variants of the polymerase chain reaction. Knowing such advances is fundamental to our performance as health care professionals, allowing us to act and make sound decisions for the benefit of the patient, according to available resources.