PubMed Health⌕ Search

Biomedical subjects

M D Gokhale

Publications and source records attributed to M D Gokhale.

22 records · Page 2Linked to original sources

Insecticide susceptibility status & enzyme profile of Aedes albopictus populations from different localities of Maharashtra state.

Susceptibility status of five populations of Ae. albopictus mosquitoes from Maharashtra state, to DDT, malathion, fenitrothion, bromophos, propoxur and deltamethrin was studied and compared with the laboratory population. Four populations survived when adults were exposed to 4 per cent DDT impregnated paper for 2 h; though three of these populations had lower DDT-LC50 values at larval stages in comparison with the laboratory population. Results of topical application of DDT on these four populations supported these findings by showing comparatively higher LD50 values at adult stages in comparison with the laboratory population. All the populations were highly susceptible to other pesticides tested i.e., malathion, fenitrothion, bromophos, propoxur and deltamethrin. These populations were distinguished from each other by esterase isoenzyme patterns.

Aedes↗

Insecticide susceptibility status of certain populations of Aedes aegypti mosquito from rural areas of Maharashtra state.

Ae. aegypti mosquitoes from rural areas of Maharashtra state were subjected to insecticide bio-assays. All the populations showed resistance to DDT at larval and adult stages. No resistance to deltamithrin and malathion was detected at any stage. Biochemical analysis of these mosquito populations showed that resistance to DDT was probably due to increase in the kinetics of glutathione S-transferase.

Aedes↗

Role of gregarine parasite Ascogregarina culicis (Apicomplexa: Lecudinidae) in the maintenance of Chikungunya virus in vector mosquito.

Ascogregarina culicis and Ascogregarina taiwanensis are common gregarine parasites of Aedes aegypti and Aedes albopictus mosquitoes, respectively. These mosquito species are also known to transmit dengue and Chikungunya viruses. The sporozoites of these parasites invade the midgut epithelial cells and develop intracellularly and extracellularly in the gut to complete their life cycles. The midgut is also the primary site for virus replication in the vector mosquitoes. Therefore, studies were carried out with a view to determine the possible role of these gregarines in the vertical transmission of dengue and Chikungunya viruses from larval to adult stage. Experiments were performed by exposing first instar mosquito larvae to suspensions containing parasite oocysts and viruses. Since Ascogregarina sporozoites invade the midgut of first instar larvae, the vertical transmission was determined by feeding the uninfected first instar larvae on the freshly prepared homogenates from mosquitoes, which were dually infected with viruses and the parasite oocysts. Similarly, the role of protozoan parasites in the vertical transmission of viruses was determined by exposing fresh first instar larvae to the dried pellets of homogenates prepared from the mosquitoes dually infected with viruses and the parasite oocysts. Direct vertical transmission and the vertical transmission of CHIK virus through the oocyst of the parasites were observed in the case of Ae. aegypti mosquitoes. It is suggested that As. culicis may have an important role in the maintenance of CHIK virus during the inter-epidemic period.

Aedes↗