A laser doppler study of the effect of 2-alkylthio-4-ethyl-4-methyl-4,5 dihydro-1H-imidazolin-5-one oxime (oxime) on the ischaemic rat lower limb.

The potential vasodilator effect of the novel compound 2-alkylthio-4-ethyl-4-methyl-4,5 dihydro-1H-imidazolin-5-one oxime (oxime) was investigated in a model of lower limb ischaemia induced in rats by unilateral ligation of the right femoral artery using Laser Doppler Flowmetry. The effect of oxime was compared with that of isoprenaline or L-arginine. Test drugs were injected systemically into the femoral vein or applied locally on the planter surface of the rat hind paw. Serum level of nitrite (NO(2) (-)) and nitrate (NO(3) (-)) were measured by ELISA. Immediately after operative induction of right lower limb ischaemia, blood flow ratio (Right/Left limb ratio: BFR) decreased to 0.33-0.39 in different groups. The intravenous (i.v.) administration of oxime increased BFR in a dose-dependent manner. Compared with pre-drug BFR, oxime administered at doses of 0.064, 0.128 or 0.256 mg/kg increased BFR to 178.8, 328.9 and 705.9 %, respectively. Meanwhile, L-arginine given i.v. at 100 mg/kg increased BFR to 560 %. Isoprenaline given i.v. at 1 microg/kg increased BFR to 274.3 %, while isoprenaline combined with oxime (0.064 mg/kg) increased BFR to 402.7 %. Similarly, after topical application of oxime, BFR increased to 113.5, 261.1 and 433.3 %, respectively. L-arginine given at 1000 mg/kg increased BFR to 389.7 %. Isoprenaline given at 10 microg/kg increased BFR to 231.6 %, while isoprenaline administered in combination with oxime (0.064 mg/kg) increased BFR to 308.3 %. The concentration of NO in serum was significantly increased after systemic or topical administration of either 0.128 and 0.256 mg/kg oxime or 100 and 1,000 mg/kg L-arginine, respectively. It is concluded that systemic or topical oxime results in marked enhancement of blood flow in the rat ischaemic lower limb. This effect of oxime is likely to be mediated through the release of NO.

Efficacy of botanical extracts from Callitris glaucophylla, against Aedes aegypti and Culex annulirostris mosquitoes

Using standard WHO methodology, this study investigated the susceptibility of 4(th) instar Aedes aegypti (L) and Culex annulirostris (Skuse) larvae to three extracts from Callitris glaucophylla (J. Thompson & L. Johnson) (1: steam distillation extract, 2: liquefied refrigerant gas extract, and 3: methanol reflux extract), lambda-cyhalothrin (a synthetic pyrethroid insecticide) and fenitrothion (an organophosphorous insecticide). Cx. annulirostris was significantly more susceptible than Ae. aegypti to all tested chemicals except lambda-cyhalothrin. Responses to the three C. glaucophylla extracts were exceptional for a botanical compound: Cx. annulirostris (LC(50) = 0.23, 9.53 and 38.95 mg/L) and Ae. aegypti (LC(50) = 0.69, 5.21 and 306.43 mg/L). Both Cx. annulirostris and Ae. aegypti larvae were significantly more susceptible to lambda-cyhalothrin (LC(50) = 0.00013 and 0.00016 mg/L) than fenitrothion (LC(50) = 0.0009 and 0.004 mg/L). As expected, the pyrethroid and organophosphorous insecticides were far more potent than the crude C. glaucophylla extracts. The steam distilled extract was fractionated and the major components guaiol and citronellic acid were identified and tested. Activities for these major components were lower than observed for the distillate. Minor components include lactones such as eldanolide, and future testing of minor components may indicate the active component.

Hepatitis C Virus and related changes in immunological parameters in non Hodgkin's lymphoma patients.

Viral hepatitis is a common and important problem in immunocompromised cancer patients. The present study was conducted to investigate changes in some cellular and humoral immunological parameters as a consequence of HCV infection in non Hodgkin's lymphoma patients (NHL). The study included 40 NHL patients: 20 anti-HCV antibody positive (Gr. I ), and 20 anti-HCV antibody negative (Gr.II ). In addition, forty non-cancer controls (NCCs) were included: 20 of them were anti-HCV antibody positive (Gr. III) and 20 anti-HCV antibody negative (Gr. IV). The studied immunological parameters included serum levels of interleukin-1 (IL-1), interleukin-2 (IL-2), interleukin-6 (IL-6), and soluble tumor necrosis factor receptors (s-TNFr) measured by ELISA, as well as assessment of T and B lymphocyte subsets by PAP immunostaining method. Mean IL-1 level (pg/ml) was significantly higher in Gr. 1 (14 +/- 6) and Gr. III (20 +/- 12) as compared to those in Gr. II (7 +/- 5) and Gr. IV (9 +/- 6). Mean IL-2 level (pg/ml) was also significantly higher in Gr. I (132 +/- 101) and Gr. III (135 +/- 59) compared to those in Gr. II (36 +/- 29) and Gr. IV (31 +/- 48). On the other hand, level of IL-6 showed no significant difference between groups. The mean level of sTNF-r, (ng/ml) was only significantly higher in Gr. I (2.9 +/- 1.7) when compared to that in Gr. IV (1.9 +/- 2.2). In group IV, the average percentage of CD3 (70 +/- 4%) and CD4 (44 +/- 5%) were significantly higher than in those of Gr. I (CD3 = 51 +/- 11%, CD4 = 30 +/- 12%), Gr. II (CD3 = 52 +/- 7%, CD4 = 30 +/- 8%), and Gr. III (CD3 = 52 +/- 9%, CD4 = 26 +/- 8%). From all the above immunological and virological features two main tips could be inferred: (1) HCV leads a mild course of infection in NCCs evidenced by normal ALT level in all but 20% of subjects, normal IL-6, sTNF-r, lower counts of CD4+ T cells and hence a mild hepatocellular injury, and (2) In the immunocompromised NHL patients the virus leads potentially more aggressive course as evidenced by higher viremia, as well as significant elevation in sTNF-r, and CD8+ depression.