No abstract

Dengue virus is a ssRNA+ flavivirus, which produces the dengue disease in humans. Currently, no specific treatment exists. siRNAs regulate gene expression and have been used systematically to silence viral genomes; however, they require controlled release. Liposomes show favorable results encapsulating siRNA for gene silencing. The objective herein was to design and evaluate in vitro siRNAs bound to liposomes that inhibit DENV replication. siRNAs were designed against DENV1–4 from conserved regions using siDirect2.0 and Web-BLOCK-iT™ RNAiDesigner; the initial in vitro evaluation was carried out through transfection into HepG2 cells. siRNA with silencing capacity was encapsulated in liposomes composed of D-Lin-MC3-DMA, DSPC, Chol. Cytotoxicity, hemolysis, pro-inflammatory cytokine release and antiviral activity were evaluated using plaque assay and RT-qPCR. A working concentration of siRNA was established at 40 nM. siRNA1, siRNA2, siRNA3.1, and siRNA4 were encapsulated in liposomes, and their siRNA delivery through liposomes led to a statistically significant decrease in viral titers, yielded no cytotoxicity or hemolysis and did not stimulate release of pro-inflammatory cytokines. Finally, liposomes were designed with siRNA against DENV, which proved to be safe in vitro.

Introducción: La antibiótico-resistencia es un fenómeno por el cual las bacterias logran sobrevivir al tratamiento con antimicrobianos; con incidencia en ambientes intra y extrahospitalarios como: fuentes hídricas, sector agrario/ganadero y fómites. Objetivo: Describir bacterias presentes en fómites de alta circulación en una región centro-occidental de Colombia junto a su perfil de sensibilidad fenotípica y presencia de genes para betalactamasas tipo TEM-full, OXA-3 y SHV-full. Metodología: Se aislaron cepas bacterianas de billetes, pasamanos de escaleras eléctricas y botones de cajeros automáticos; se evaluó su perfil de sensibilidad fenotípica por medio de concentración mínima inhibitoria-técnica automatizada/Vitek2® y genes para betalactamasas tipo TEM-full, OXA-3 y SHV-full mediante PCR convencional. Resultados: Se obtuvo 30 aislados; Acinetobacter baumannii complex, fue la más común; el fómite con mayor aislados y resistencia fueron los billetes; el 53% portó al menos uno de los genes estudiados. Se identificaron bacterias gramnegativas con resistencia frente a: Imipinem, Piperacilina/Tazobactam, Colistina, Ceftazidima, Tigeciclina y Ceftriaxona; bacterias grampositivas con resistencia frente a: Quinupristina/Dalfopristina, Minociclina, Tetraciclina, Teicoplanina, Nitrofuratoina, Oxacilina, Clindamicina, Trimetropina-sulfametoxazol, y Minociclina. Conclusión: Teniendo en cuenta la circulación de cepas con estas resistencias, es importante la educación en la comunidad para evitar la adquisición o propagación de infecciones por manipulación inadecuada de fómites.

Infection through the Hepatitis C virus does not have a vaccine and treatment with pegylated interferon and ribavirin can fail; which is why it may cause chronic infection and, consequently, could develop liver failure or hepatocellular carcinoma. It has been described that virus-cell recognition occurs between the E2 viral envelope protein and diverse cell receptors, with this interaction being critical in viral infection. which is why the study sought to identify inhibitory peptides of the interaction between viral E2 protein and the CD81 and CD209 receptors. Methodology: Through the RCSB protein database, crystals from the CD81 and CD209 receptors were selected, CD81/E2-HCV, CD209/E2-HCV complexes were carried out by SWISS-MODEL to generate inhibitory peptides of protein interaction through the Rosetta web server, this interaction was validated through ClusPro and finally, determined the theoretical physicochemical and cytotoxic properties of these peptides. Results: two peptides were obtained, without predicted toxicity, with a theoretical capacity of blocking the protein interaction between the E2 protein of the virus and CD81 and CD209.