Insecticide resistance in Anopheles stephensi in Somali Region, eastern Ethiopia
MALARIA JOURNAL
Authors: Yared, Solomon; Gebressielasie, Araya; Damodaran, Lambodhar; Bonnell, Victoria; Lopez, Karen; Janies, Daniel; Carter, Tamar E.
Abstract
Background The movement of malaria vectors into new areas is a growing concern in the efforts to control malaria. The recent report of Anopheles stephensi in eastern Ethiopia has raised the necessity to understand the insecticide resistance status of the vector in the region to better inform vector-based interventions. The aim of this study was to evaluate insecticide resistance in An. stephensi in eastern Ethiopia using two approaches: (1) World Health Organization (WHO) bioassay tests in An. stephensi; and (2) genetic analysis of insecticide resistance genes in An. stephensi in eastern Ethiopia. Methods Mosquito larvae and pupae were collected from Kebri Dehar. Insecticide susceptibility of An. stephensi was tested with malathion 5%, bendiocarb 0.1%, propoxur 0.1%, deltamethrin 0.05%, permethrin 0.75%, pirimiphos-methyl 0.25% and DDT 4%, according to WHO standard protocols. In this study, the knockdown resistance locus (kdr) in the voltage gated sodium channel (vgsc) and ace1R locus in the acetylcholinesterase gene (ace-1) were analysed in An. stephensi. Results All An. stephensi samples were resistant to carbamates, with mortality rates of 23% and 21% for bendiocarb and propoxur, respectively. Adult An. stephensi was also resistant to pyrethroid insecticides with mortality rates 67% for deltamethrin and 53% for permethrin. Resistance to DDT and malathion was detected in An. stephensi with mortality rates of 32% as well as An. stephensi was resistance to pirimiphos-methyl with mortality rates 14%. Analysis of the insecticide resistance loci revealed the absence of kdr L1014F and L1014S mutations and the ace1R G119S mutation. Conclusion Overall, these findings support that An. stephensi is resistant to several classes of insecticides, most notably pyrethroids. However, the absence of the kdr L1014 gene may suggest non-target site resistance mechanisms. Continuous insecticide resistance monitoring should be carried out in the region to confirm the documented resistance and exploring mechanisms conferring resistance in An. stephensi in Ethiopia.
Microvascular Density and Circulating Endothelial Progenitor Cells Before and After Treatment with Incretin Mimetics in Diabetic Patients
HIGH BLOOD PRESSURE & CARDIOVASCULAR PREVENTION
Authors: De Ciuceis, Carolina; Agabiti-Rosei, Claudia; Rossini, Claudia; Caletti, Stefano; Coschignano, Maria Antonietta; Ferrari-Toninelli, Giulia; Ragni, Giorgio; Cappelli, Carlo; Cerudelli, Bruno; Airo, Paolo; Scarsi, Mirko; Tincani, Angela; Porteri, Enzo; Rizzoni, Damiano
Abstract
IntroductionGlucagon-like peptide 1-receptor agonists (incretin mimetics) and dipeptidyl peptidase-4 inhibitors (incretin enhancers) have been recently introduced in the treatment of diabetes mellitus. In particular, incretin mimetics seems to have ancillary antioxidant/antinflammatory properties that might be involved in endothelial protection.AimTo investigate the effect of incretin mimetic therapy (liraglutide, exenatide) given to 11 patients with type 2 diabetes mellitus, on circulating endothelial progenitor cells (EPCs) (bone marrow-derived cells possibly participating in neovascularization and endothelial protection and repair) and capillary density.MethodsFour diabetic patients were treated with exenatide (5g twice daily for 4weeks and then 10g twice daily for 3weeks) and 7 with liraglutide (0.6mg per day for 1week and then 1.2mg per day for 3weeks). Peripheral venous blood samples were obtained before treatment (basal) and after 4week in patients treated with liraglutide, and after 4 and 7weeks in patients treated with exenatide, since drug titration is usually longer. EPCs were evaluated by flow cytometry as CD34(+)/KDR+ cells. Capillary density was evaluated by videomicroscopy, before and after venous congestion, in the dorsum of the 4th finger.ResultsPatients treated with liraglutide (6 males 1 female, age 5412years) showed a decrease in body mass index and blood pressure during treatment, while patients treated with exenatide (3 males 1 female, age 57 +/- 6years) did not show any relevant change. EPCs were significantly increased after treatment with exenatide, but not after treatment with liraglutide. Capillary density was slightly increased only after 4 weeks of treatment with exenatide, however the increase was no longer present at the final evaluation.ConclusionsTreatment with exenatide, but not with liraglutide, was able to increase the number of circulating EPCs, possibly through an antioxidative/antiinflammatory effect.