Differential responses of anopheles stephensi [diptera: culicidae] to skin emanations of a man, a cow, and a guinea pig in the olfactometer

Biting habit of mosquitoes plays an important role in the epidemiology of mosquito-borne diseases. Mosquitoes use a set of elaborate sensory modalities to find their preferred hosts by exploiting cues emanating from a nearby host. It has been suggested that the chemical profile of skin can provide further support for anthropophilic mosquito species to find their suitable hosts. This study aimed at revealing the value of skin emanation for a zoophilic species like Anopheles stephensi as a model. Skin emanations of a man, a cow and a Guinea pig were collected by ethanol soaked cottons. Upwind responses of mosquitoes to 100 and 200 micro L of filtered skin materials were non-competitively explored in a dual-choice olfactometer. L-lactic acid and other chemical content of the skin samples were identified by an enzymatic kit and GC-MS, respectively. Unexpectedly, only human skin emanation was resulted in the statistically significant activation and attraction responses of Anopheles. stephensi in the wind tunnel. L-lactic acid content of this skin sample was 10 and 29 times more than the cow and the Guinea pig, respectively. The possible role of lactic acid and a few other identified compounds have been discussed here. An. stephensi showed higher and more specific upwind responses to human skin emanation in the olfactometer. Undoubtedly, the thorough explanation of this unexpected finding needs further investigation. But, if new data verify this result, then, it may be necessary to reconsider the role of skin emanation and thence the human blood index and vectorial capacity of this zoophilic mosquito

Systematics, bioecology, and medical importance of Widow Spiders [Lathrodectus spp.] in Khorasan province, Iran

Following the hospitalization of 195 individuals due to the spider bite in 1995 and three cases of recorded death in the year of 1993 which were referred to Emam Reza Hospital in Mashad, the present study was undertaken on bionomics and medical importance of Lathrodectus spp in Khorasan Province, during 1995-2005. A total cases of 195 bites were studied composing of 70.8% males and 29.2% females. The most prevalence cases were observed in mid age [20-55 years old] and particularly among farmers [36.4%]. A total number of 216 adult widow spiders and 258 egg sacs were collected from their habitats in different localities of 15 counties in the province. The following species have been recognized: Lathrodectus tredecimgottatus [62%], L. dahli [32%], L. geometricus [5%] and L. pallidus [1%]. Here is the first report on the occurrence of males of L. pallidus as well as both sexes of L. trdecimgottatus and L. geometricus in the country. The sex ratio among collected specimens was 88% and 12% female and male, respectively. Summer provides the most suitable and favorable climatic condition for the activities of these spiders. However 65% of spiders were collected in this season. Among different cities, Mashad had [60%] the most reported cases in the study area. Foot was more injured than other parts. 96.5% of patients exhibited localized pain from which only 2% had no pain in the bitten part and 87% had a generalized pain in whole body

[Study of the effect of hemiscorpius lepturus venom on levels of WBC, RBC and hematocrit in rats]

Hemiscorpius lepturus scorpion present in the southern provinces of the country, especially inKhoozestan stings a lot of people that results in long-standing dangerous side effects and sometimes evenmortality. As the study of the effects of this scorpion venom on some laboratory animals can determine itsmechanism of action and help us to cure people stung by scorpions, this study has been done to study the effectsof Hemiscorpius lepturus venom on levels of WBC, RBC and hematocrit of rats.An experimental study has been done on 51 rats of the same race with approximate age of 2-3 months,and weight of 200-250 grams. . All the hematological features including WBC [White Blood Cell], RBC [RedBlood Cell] and HT [Hematocrit] were measured prior to venom injection. The same procedures were followedafter injection of 1 microlitre of venom. Results before and after injection have been analyzed by WilcoxonMatched, Pairs signed and Ranks statistical tests.The results of the study have shown that the venom caused changes in the levels of WBC, RBC andHematocrit. The mean level of WBC at the start was 10234, whereas following the venom injection it reached tothe level of 11757 [P < 0.0007]. The mean number for RBC before the treatment was 7509130 and after injection,the number declined to 7065098 [P < 0.0001]. The average amount of Hematocrit before and after injection was40.087% and 39.0588%, respectively [P < 0.001].Hemiscorpius lepturus venom has some effects on the levels of WBC, RBC and hematocrit of rats.The study of the hematological changes in humans can lead to better study of the effect of this venom andconsequently suitable cure for the injured