Experimental studies on vaccination of rabbits against hard ticks [hyalomma dromedarii]

Boscat while rabbits were vaccinated with Hyalomma dromedarii tick eggs antigen [Antigen I] and sex organs with midgut antigen [Antigen II]. Both antigen were exposed to electrophorytic analysis. The rabbit received two inoculations subcutaneously on 0 day and after 2 weeks. The effect of the immunity induced was determined by enzyme linked immunosorbent assay [ELISA] and by infesting the rabbits with adult H.dromedarii ticks. In immunized rabbits, the antibody titer was detected in scrum. A significant reduction in tick weight, egg mass weight, ovipositor period and percentage of eggs hatchability were found. Three specific immunogenic bands were detected for antigen I and four for antigen II. Sex organs with midgut antigen induced best protection than eggs antigen

Spectrophotometric determination of piroxicam using 2,2-diphenyl-1-picrylhydrazyl1]

An indirect spectrophotometric method has been developed for the determination of piroxicam by interaction with 2,2-diphenyl-1-picrylhydrazyl [DPPH]. The DPPH reagent is an intense violet-colored stable free radical which is discolored on reaction with the drug. The decrease in violet color is used as measure of the quantity of the drug present. Beer's Law is obeyed in the concentration range of 2-20 mug of piroxicam per ml [sigma max = 1.66 x 10 4 mol -1 cm -1]. No interference occurred by the degradation product of the drug [2-aminopyridine] or the common excipients in pharmaceutical preparations. A reaction pathway was suggested and verified by the synthesized piroxicam cyclodehydration product. The structure of the latter compound was confirmed by TLC, IR and PMR spectroscopy

Synthesis of some nalidixic acid derivatives

Esterification of nalidixic acid [I] using dicyclohexylcarbodiimide [DCC] [III] has been studied. A crystalline compound was isolated as the main product from the reaction under several conditions, in presence or absence of alcoholic nucleophiles. Homogenity of the product was confirmed by TLC. The separated compound was assigned to be N-nalidixyldicyclohexylurea [IV] on the basis of spectral data [IR, 1H-, 13C-NMR and MS] as well as elemental analysis. Esterification of nalidixic acid has been achieved under comparatively mild conditions, using ethyl chloroformate as modifying agent for the carboxylic group. The structures of the synthesized esters were confirmed with reference to reported data as well as spectral [IR, PMR] and elemental analyses