Schistosomiasis is a public health problem in many developing countries. Control of the snail intermediate hosts of Schistosoma is a promising method for eliminating this disease. Copper (Cu-chl) and magnesium chlorophyllin (Mg-chl) are potent photosensitisers used in diverse biological applications. Their effects on the fecundity of Biomphalaria alexandrina (Ehrenberg): its reproductive rate (R 0 ) and total levels of progesterone, testosterone and estradiol were evaluated. Besides, we determined the production of cercariae of S. mansoni. The concentrations LC 10 and LC 25 of Cu-chl and Mg-chl significantly reduced the fecundity and R 0 of the treated snails which could be partially due to the decrease in the level of steroid sex hormones. The reduction rates of R 0 for the snails treated with LC 10 Cu-chl and Mg-chl were 72.7% and 89.7%, respectively. Moreover, Cu-chl and Mg-chl significantly suppressed the cercarial production which dropped from 9,778 cercariae per snail in the light control group to 3,126 and 107 cercariae per snail in the groups treated with LC 10 Cu-chl and Mg-chl 21 days after exposure to miracidia, respectively. Since Cu-chl and Mg-chl negatively interfere with the parasite transmission, they should be considered in schistosomiasis control programmes.

This work is concerned with studying the effect of Green synthesized Silver Nanoparticles (GSNPs) on the mosquito larvae of Culex pipiens. The lethal concentration LC10, LC50 and LC90 were obtained from the established regression log concentrateresponse lines after 24 hours of exposure. Results implied significant increasing mortality rate upon increasing the lethal concentrations of GSNPs which recorded 0.576 ppm, 1.719 ppm and 5.129 ppm for LC10, LC50, and LC90 respectively. For investigating the root cause of mortality, data indicated that there was a significant increase of lipid peroxidation level in tissue homogenates of larvae treated with the increasing of above mentioned lethal concentrations of GSNPs, which recorded 17.25 nmol /g.tissue, 18.0 nmol /g.tissue and 25.0 nmol /g.tissue for LC10, LC50, and LC90 respectively, compared to control sample which recorded 16.0 nmol /g. tissue. At the meantime, data also revealed a significant increase in levels of total protein, albumin and globulin levels in tissue homogenates of larvae previously treated with the increasing of above mentioned lethal concentrations of GSNPs , which recorded, 0.231 g/dl , 0.109 g/dl and 0.122 g/dl for LC10, 0.735 g/dl, 0.115 g/dl and 0.62 g/dl for LC50, 0.93 g/dl ,0.125 g/dl and 0.805 g/dl for LC90 for total protein, albumin and globulin, respectively, compared to control samples which recorded 0.21 g/dl , 0.089 g/dl and 0.121 g/dl, for the same biochemical parameters respectively.

No abstract

No abstract

No abstract