Background: Anopheles culicifacies s.l., a major malaria vector in India, has developed widespread resistance to DDT and is becoming resistant to pyrethroids-the only insecticide class recommended for the impregnation of bed nets. Knock-down resistance due to a point mutation in the voltage gated sodium channel at L1014 residue (kdr) is a common mechanism of resistance to DDT and pyrethroids. The selection of this resistance may pose a serious threat to the success of the pyrethroid-impregnated bed net programme. This study reports the presence of kdr mutation (L1014F) in a field population of An. culicifacies s.l. and three new PCR-based methods for kdr genotyping.

No abstract

No abstract

No abstract

Nitric oxide (NO) has dicotomic influence on modulating host-parasite interplay, synchronizing physiological orchestrations and diagnostic potential; instigated us to investigate the plausible association and genetic regulation among NO level, components of oxidative stress, iNOS polymorphisms and risk of malaria. Here, we experimentally elucidate that iNOS promoter polymorphisms are associated with risk of malaria; employing mutation specific genotyping, functional interplay using western blot and RT-PCR, quantitative estimation of NO, total antioxidant content (TAC) and reactive oxygen species (ROS).Genotyping revealed significantly associated risk of P. vivax (adjusted OR = 1.92 and 1.72) and P. falciparum (adjusted OR = 1.68 and 1.75) infection with SNP at iNOS-954G/C and iNOS-1173C/T positions, respectively; though vivax showed higher risk of infection. Intriguingly, mutation and infection specific differential upregulation of iNOS expression/NO level was observed and found to be significantly associated with mutant genotypes. Moreover, P. vivax showed pronounced iNOS protein (2.4 fold) and mRNA (2.5 fold) expression relative to healthy subjects. Furthermore, TAC and ROS were significantly decreased in infection; and differentially decreased in mutant genotypes.Our findings endorse polymorphic regulation of iNOS expression, altered oxidant-antioxidant components and evidences of risk association as the hallmark of malaria pathogenesis. iNOS/NO may serve as potential diagnostic marker in assessing clinical malaria.