Prevalence of Toxoplasma gondii antibodies in sera of turkeys, chickens, and ducks from Egypt.

Sera from 173 turkeys, 108 chickens, and 48 ducks from Giza, Egypt, were tested for the presence of anti-Toxoplasma gondii antibodies by means of the modified agglutination test using mercaptoethanol and formalin-fixed tachyzoites. The prevalence of anti-T. gondii antibodies (>1:25) among turkeys, chickens, and ducks was 59.5%, 47.2%, and 50%, respectively.

Evidence of Onchocerca fasciata (Filarioidea: Onchocercidae) in camels (Camelus dromedarius): I-prevalence, nodular lesions appearance and parasite morphology.

Examination of 3376 imported and 200 local Egyptian camels was carried out during the period extending between September 1997 and August, 1998. These animals were carefully examined for the presence of Onchocerca fasciata nodules and subsequently for O. fasciata adult parasites. Results of this study revealed that imported camels had the higher infection rate (2.75%), while those of local origin showed no palpable or detected Onchocerca nodules. Distribution of these nodules was mainly on the two sides of abdomen, hind limbs (concentrated in thigh region) and fore limbs particularly on the shoulders and nuchal ligament. This distribution varied according to the degree of infection. Searches for microfilariae were also performed using either blood samples, or in the subcutis and fascial sheath near or around the detected nodules.

Characterization of antigenic property of Toxocara canis and Toxascaris leonina adults and larvae through immunodiagnostic electrophoresis (SDS-PAGE) and western blot technique.

Differential molecular studies were performed by sodium dodecyle sulphate polyacrylamide gel electrophoresis--SDS-PAGE--between somatic antigen of Toxocara canis and Toxascaris leonina, adults and larvae, recovered from dogs. SDS-PAGE of both adults somatic antigen showed two closely similar bands (90.00, 91.95 KDa and 69.25-70.56 KDa). Each parasite had characteristic bands clustered in different molecular weights. While for their larval antigen, T. canis showed a very different antigenic profile when analysed in comparison to T. leonina antigen except at one band (66.85-66.89 KDa). The Western blot analysis showed four prominent bands represented immunoreaction between the separated somatic antigen of T. canis adults and experimentally immunized rabbit with the corresponding parasite (125.37, 117.73, 90.00 and 69.25 KDa). While separated antigen of T. leonina adults immune reacted with the corresponding hyperimmune rabbit sera at 119.04, 91.95 and 70.56 KDa. The Western blot showed cross reactive immune bands between T. canis and T. leonina adults somatic antigen at two bands (90.00, 91.95 KDa and 69.25-70.56 KDa). The polypeptide bands reacted at 125.37 KDa and 117.73 KDa can be used as specific finger print for T. canis adults while that at 119.04 KDa was specific for T. leonina adult worm.

An enzyme linked immunosorbent assay for serodiagnosis of Taenia hydatigena metacestode infection in sheep.

Serological examination of 500 sheep serum samples obtained from cairo Abattoir during the period from January 1997 to September 1997 using enzyme linked immunosorbent assay (ELISA), revealed that 151 samples (30.2%) were seropositive for Taenia hydatigena metacestodes with optical density mean value 1.09 +/- 0.09, 0.56 +/- 0.09 and 0.31 +/- 0.04 for heavy, moderate and light infected animals respectively. Out of 100 positive animals at postmortem (PM), 91 were seropositive with ELISA test with a sensitivity rate 91%. Sixty animals (15%) from 400 negative ones at PM showed positive reaction, while 340 animals (85%) showed negative reaction with ELISA test.

Some studies on the growth and development of Echinococcus granulosus, camel origin in experimentally infected dogs.

The development of Echinococcus granulosus of camel subspecies in 35 experimentally infected dogs was studied at 3, 7, 10, 13, 18, 23, 35 and 56 days post-infection (d.p.i.). The morphological characteristics of each developmental stage is studied and discussed. Morphological characters included number, total length, shape, arrangement of rosteller hooks and blade length to total length percentage (B1/T1%). In addition, total worm length, scolex, suckers, rostellum, neck and segments were measured and described. Other useful characters are considered to be the position of common genital pore, number and distribution of testes, uterus, shape of ovary and vitelline glands. Generally, the results indicated that the segmentation first appears at 18 d.p.i. Moreover, male and female genitalia could be detected at the same period. However, completely developed genitalia appeared at 56 d.p.i. Histological examination of the small intestine of experimentally infected dogs revealed that the parasites were found in distended and thin wall crypts of Liberkuhn at the periods of 3.7 and 10 d.p.i, while the parasite scoleces were found embeded in the mucosa at the periods of 13, 18 and 23 d.p.i. No significant pathological changes were encountered in both infected and control dogs. The data presented here are the first report of strobilar development of E. granulosus of camel origin in experimentally infected dogs.

Some studies on the growth and development of Echinococcus granulosus, camel origin in experimentally infected dogs.

Development of Echinococcus granulosus of camel subspecies in 35 experimentally infected dogs was performed at 3, 7, 10, 13, 18, 23, 35 and 56 days post-infection (d.p.i.). Morphological characters of each developmental stage was studied and discussed. Generally, the results indicate that the segmentation firstly appeared at 18 d.p.i. Also, male and female genitalia could be detected at the same period. However, completely developed of genitalia appeared at 56 d.p.i. Histological examination of small intestine of experimentally infected dogs revealed that the parasites were found in distended and thin wall crypts of Liberkuhn at 3, 7, & 10 d.p.i, while the parasite scolices were found embedded in the mucosa at 13, 18 & 23 d.p.i. No significant pathological changes were encountered in both infected and control dogs. This is the first report of strobilar development of E. granulosus of camel origin in experimentally infected dogs.

Aminoglycoside levels in the rabbit vitreous cavity after intravenous administration.

PURPOSE: To determine the penetration of gentamicin and amikacin into the rabbit vitreous cavity after their intravenous administration. METHODS: Gentamicin (1.6 mg/kg every 8 hours) and amikacin (6 mg/kg every 12 hours) were administered intravenously to 25 rabbits that had previously had the lens and vitreous removed from 43 eyes. For each drug, ocular inflammation was induced in one group of eyes by injection of heat-killed Staphylococcus epidermidis, while the other group was maintained as a control. Samples from the vitreous cavity were taken at regular intervals for 72 hours after beginning the intravenous medications and were analyzed for drug concentrations. RESULTS: The maximum intravitreal concentration +/- SD achieved for gentamicin was 1.8 +/- 0.5 microgram/ml. The maximum intravitreal concentration for amikacin was 8.5 +/- 3.2 micrograms/ml. Inflamed eyes demonstrated higher concentrations than did those without inflammation. CONCLUSIONS: In a rabbit model with conditions optimized to enhance penetration of antimicrobials into the vitreous cavity after intravenous administration, neither gentamicin nor amikacin penetrated sufficiently to reach potentially therapeutic concentrations consistently for either Pseudomonas or S epidermidis organisms.

Vancomycin levels after intravitreal injection. Effects of inflammation and surgery.

OBJECTIVE: Vancomycin hydrochloride for intraocular injection is the drug of choice for the treatment of suspected gram-positive endophthalmitis. To study its intraocular pharmacokinetics, we injected vancomycin into the vitreous cavity of phakic, aphakic, and aphakic-vitrectomized rabbit eyes and determined its rate of clearance. Inflamed eyes were compared to control eyes in each group. METHODS: Three groups of eyes were prepared. The eyes in Group 1 were phakic, the eyes in Group 2 had the lens removed, and the eyes in Group 3 had both the lens and central vitreous removed. Each group was subdivided into a control group and a group made inflamed by injection of heat-killed Staphylococcus epidermidis. Vancomycin hydrochloride 1 mg in 0.1 cc of diluent was injected into the midvitreous cavity and samples obtained at 2 or 3, 8, 24, and 48 hours after injection. Vancomycin concentrations were measured and clearance rates were calculated for each of the groups. RESULTS: Vancomycin was cleared substantially faster from aphakic-vitrectomized eyes (half-life 9.0 hours) and aphakic eyes (half-life 8.9 hours) than phakic eyes (half-life 25.1 hours). Inflammation increased the rate of elimination of vancomycin only in the aphakic group. CONCLUSIONS: Clearance of vancomycin from the phakic eye is prolonged compared to that of beta-lactam antibiotics, an important pharmacokinetic advantage in treating endophthalmitis. Its clearance from aphakic-vitrectomized eyes is dramatically faster than from phakic eyes and is similar to that of other antimicrobial agents.

Effects of inflammation and surgery on amikacin levels in the vitreous cavity.

Intraocular injection of amikacin is increasingly used in the treatment of endophthalmitis. We injected 400 micrograms of amikacin into the vitreous cavity of rabbit eyes to study its pharmacokinetics. Phakic, aphakic, and aphakic vitrectomized eyes were injected, and inflamed eyes were compared to control eyes. Vitreous concentrations were determined at two, eight, 24, and 48 hours, and clearance rates were calculated. Amikacin is cleared considerably more quickly from aphakic (half-life, 14.3 hours) than phakic control eyes (half-life, 25.5 hours) and even more quickly from aphakic vitrectomized eyes (half-life, 7.0 hours). Inflammation substantially increased the rate of clearance in aphakic eyes. In inflamed aphakic and aphakic vitrectomized eyes, vitreous drug levels were equal to or below the minimal inhibitory concentration for most organisms considered sensitive to amikacin at 24 hours. Supplementation of intraocular antibiotics may therefore be required in clinical settings.