Bioavailability to rats of 14C-lindane residues in stored potato tubers.

Potato tubers were applied with radiolabelled lindane (U-14C gamma- 1,2,3,4,5,6-hexachlorocyclohexane) at three dose levels 30, 150, and 300 ppm and stored for 30, 60 and 90 days at room temperature. The data revealed that lindane penetrated into the pulp tissues through the epidermal layer. The amounts recovered in the peel were found to increase with a greater storage period up to 60 days followed by a drop at 90 days. On the other hand, there was a slight increase in radioactivity in the pulp tissue from 30 to 60 days followed by significant increase after 90 days. The incorporation of the compound in the tubers was dose independent. Methanol extraction showed binding of about 8.1% and 5.8% of the applied dose in peel and pulp tissues, respectively. The insecticide was found to be bioavailable when rats health hazard. It is therefore, desirable to demonstrate that the quantity of the terminal residues may be safe for the consumer. In the present investigation an attempt was made to determine the fate and bioavailability of lindane when applied to stored potato tubers.

Enhanced efficacy of praziquantel treatment in mice vaccinated with radiation attenuated cercariae of Schistosoma mansoni.

Normal, and vaccinated mice four weeks previously with radiation attenuated cercariae of S. mansoni (500/mouse) were challenged with normal cercariae (150/mouse), then treated one week later with praziquantel (400 mg/kg body weight, orally). Worm burden was determined to calculate the % immunity in all groups under study. Histopathological examination of liver, small and large intestine, spleen and lung was done. Serum IgE level was estimated using the immunoradiometric assay. (IRMA). The % immunity was highest among vaccinated, infected and treated group with minimal pathological changes recorded and highest IgE level. From the data collected, it was found that, the efficacy of praziquantel treatment was enhanced in vaccinated mice and that there was synergistic effect between drug treatment and vaccination when praziquantel was given seven days post-infection (challenge).

Effect of praziquantel on sex hormone levels in murine schistosomiasis mansoni.

Changes in sex hormonal levels were studied in Schistosoma mansoni infected and praziquantel treated mice (400 x 2 mg/Kg), drug control and in normal control groups. It was observed that schistosomiasis lead to increase in the level of testosterone, progesterone and 17B-esteradiol, 60 and 70 days postinfection in male and female mice, respectively. In praziquantel treated group the level of testosterone was lowered 10, 20 & 30 days post treatment, progesterone and 17 beta-estradiol fell 30 days post treatment after primary rise. The mechanism of recorded changes will be discussed in details.

The effect of praziquantel treatment on the liver functions, worm burden, and granuloma size using two drug regimen in murine Schistosoma mansoni infection.

The effect of single dose of praziquantel (400 mg/kg) or two doses on two consecutive days was studied in mice infected with S. mansoni. With the single dose there was improvement in the serum protein pattern towards pre-infection values & a transient rise in serum transaminases which soon declined to normal. Improvement was more evident after using two doses of praziquantel (P < 0.001). Worms were eradicated by 70%. 77% and 80% after the single dose and by 88%, 92% and 95% after two doses. Granuloma size was reduced by 50%, 54% and 60% after single dose and by 58% and 73% respectively after 10, 20, and 30 days from treatment.