Polydnaviruses from certain parasitoid Hymenoptera have been reported to interfere with both host immunitv and host development. Heliothis virescens larvae injected with either calyx fluid or sucrose gradient-purified polydnavirus from Microplitis croceipes (McPDV) gained less weight than saline-injected larvae. The active feeding portion of the fifth stadium larva (time to reach the burrowing-digging stage) was doubled (7.0 vs. 3.4 days) when a 0.25 wasp equivalent (WE) of sucrose gradient-purified McPDV was injected into a newly ecdysed fifth stadium host. Many of the treated larvae were unable to pupate successfully and died at a point of incomplete larval-pupal ecdysis. Pupae that did result from the treated larvae weighed significantly less than controls, even at 0.025 WE. The rate of weight gain and extent of delay of development were dose-dependent; as little as 0.1 WE extended the time of active feeding by 1.5 days and yielded only 25% adults. A 0.05 WE dose yielded 78% adults compared to 95% for controls. The total protein content of hemolymph from indi-

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According to the use of Quercus infectoria (QI) and Rosa damascena L. (RD) for therapeutic purposes and lack of adequate information about their cardiovascular effects, we investigated the cardiovascular indices of rabbits which chronically pretreated with these agents. Animal groups were control group (CTL), RD and QI groups with normal chow plus 1.5 g RD and QI extracts, respectively, in each kg of the diet for 45 days; Hyperlipidemic (H) group received high-fat diet for 45 days; H+RD and H+QI groups received high fat diet plus QI and RD extracts, respectively. Blood pressure was greater in H+RD group than CTL, RD, and H groups. Left ventricular developed pressure and left ventricular systolic pressure increased significantly in H+RD group versus CTL and RD groups (P < 0.05 and P < 0.0001, resp.) and in H+QI groups (P < 0.01 versus QI groups). Left ventricular end diastolic pressure (LVEDP) showed significant reduction in H+QI group versus H group. QI attenuated the values of total cholesterol, LDL, TG, and atherogenic indices of plasma when coadministrated with a high-fat diet. The results suggest the antilipidemic and antiatherogenic effects of QI. In addition, the use of RD along with a high-fat diet may increase the risk of hypertension in rabbits.

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Background:Until now, no experimental study has directly assessed the arrhythmogenesis of chronic consumption of anabolic androgenic steroids along with moderate-intensity endurance exercise.Objectives:We evaluated the influence of integration of anabolic androgenic steroids along with moderate-intensity endurance exercise on susceptibility to lethal ventricular arrhythmias in rat.Materials and Methods:The animal groups were as follows: control group (CTL); exercise group (EX) which were under 6 weeks of treadmill exercise; nandrolone group (Nan) which received 5 mg/kg of nandrolone decanoate twice a week; vehicle group (Arach) which received Arachis oil (solvent of nandrolone); trained vehicle group (Arach + Ex); and trained nandrolone group (Nan + Ex). One day after ending of the intervention period, arrhythmia was inducted by intravenous infusion of aconitine and ventricular arrhythmias were recorded. Then malondialdehyde (MDA) and glutathione peroxidase (GPX) of heart tissue were measured.Results:Nandrolone, exercise, and their combination were associated with heart hypertrophy. Exercise could prevent the incremental effect of nandrolone on MDA/GPX ratio. Chronic administration of nandrolone with moderate-intensity endurance exercise had no significant effect on blood pressure, heart rate, and basal electrocardiographic parameters. Combination of nandrolone and exercise significantly increased the incidence of ventricular fibrillation (VF) and reduced the VF latency (P < 0.05).Conclusions:The findings suggest that chronic coadministration of nandrolone with moderate-intensity endurance exercise facilitates the VF occurrence in rat. Complementary studies are needed to elucidate the involved mechanisms of this abnormality.