Effects of gamma radiation on the vector competence of Aedes aegypti (diptera: Culicidae) to transmit Zika virus.

One of the limitations of the Sterile Insect Technique (SIT), conventionally performed by ionizing radiation, regards separating males from females, which is not 100% effective. Some irradiated females may be released together with males in the field at SIT. The present study aimed to evaluate the influence of ionizing radiation on the ability of Aedes aegypti mosquitoes to transmit the Zika virus after exposing female pupae to a 40 Gy of gamma radiation. The results suggest that the genetic damage induced by exposure of females to this dose level promotes their total sterility, but it does not influence their vector competence. However, our data point out that ionizing radiation may decrease the proportion of infective mosquitoes.

Antibacterial activity of irradiated extracts of Anacardium occidentale L. on multiresistant strains of Staphylococcus aureus.

This study evaluated the antibacterial activity of crude and fractionated leaf extracts of Anacardium occidentale, after receiving 10 kGy from 60Co, against multiresistant strains of Staphylococcus aureus in vitro. Minimum Inhibitory Concentrations-MIC and Minimum Bacteriostatic Concentrations-MBC were respectively assessed by serial microdilution technique in multiwall plates and Petri dishes, against standard strains and clinical isolates of multiresistant S. aureus. The results pointed out a significantly increase of the antibacterial activity of the such extracts after irradiation, emphasizing the role of gamma radiation on leaf extracts of A. occidentale to improve bioactive substances, offering new raw material for antibacterial drugs.