Histological studies on praziquantel susceptible and insusceptible S. mansoni isolates

To study the biological differences of PZQ susceptible and insusceptible S. mansoni isolates; three S. mansoni isolates were studied in this work. The first one is the susceptible [Mo] isolate obtained from Egyptian villagers cured after a single oral dose PZQ [40 mg/kg]. The other two insusceptible isolates [Mt22, Mt24] were originally obtained from Egyptian villagers not cured alit three curative doses of PZQ,two doses of 40 mg / kg b.w followed by 60 mg/kg b.w This study revealed the lower PZQ efficacy on both insuceptible isolates [Mt22, Mt24] than on susceptible [Mo] isolate. Under the same circumstances the number of worm burden as well as their biological fitness [egg count/gm liver] were higher in both insusceptible isolates than susceptible one. Also, egg hatchability was low in both insusceptible isolates when compared with its absence in the susceptible one

Immunization against trichinella spiralis using antigens from different life-cycle stages: experimental study in mice

Crude antigen preparations from different life-cycle stages of T. spiralis using 10 mug and 100 mug antigen/dose were tested for their ability to immunize mice against homologous challenge infection. Immunization was assessed by accelerated expulsion of adult worms, reduction in female worm fecundity and decreased yield of muscle larvae. The dose of 100 mug proved to be more protective in all antigen preparations. The AA provided highly significant protection against adult stages [89%] and muscle larvae [80%]. NLA produced highly significant protection against muscle larvae only [76%]. MLA provided highly significant protection against adult stages [74%], female fecundity [74%] and muscle larvae [80%]. Combination of AA and MLA produced highly significant protection against adult stages [96%], female fecundity [73%] and muscle larvae [86%]. The results showed that all antigen preparations provided variable, considerable, but partial protection against challenge infection. The variations in immunization potential were discussed

Detection of pneumocystic carinii in immuno-suppressed rats by different histological stains and immunological assays

Detection of P. carinii in lung sections of 35 immunosuppressed albino rats was evaluated using five histological stains [Toluidine blue "O", Giemsa, Gram's stain, PAS and H and E] and two immunological assays [indirect immunofluorescence [IIF] and indirect immunoperoxidase [IIP]], using polyclonal antibody raised in white New Zealand rabbits against rat P. carinii. In spite of the high sensitivity of the histological stains, they yield insufficient details for easy identification with difficult interpretation. However, Gram and PAS stains provided a better visualization with easy identification of the parasite. On the other hand, both immunological assays allowed an accurate rapid interpretation to the stained slides. The IIP technique, having 100% sensitivity in detecting the precipitated parasite antigens with absolute specificity, seems to be a good diagnostic tool for detecting P. carinii in lung sections

Evaluation of Ihat in diagnosis of natural infection with trypanosoma SPP and toxoplasma in rodents

Sera of 410 murine rodents classified into 136 Mus musculus, 134 rattus and 140 Rattus norvegicus were examined for anti-Toxoplasma and anti-Trypanosoma antibodies by IHAT. Meanwhile, blood smears and tissue sections from various organs of these animals were examined, respectively, for trypomastigote stage and Toxoplasma tissue cysts. Sensitivity of IHAT was recorded to be 96.4% and 100%, respectively, for the detection of Trypanosoma and Toxoplasma infection. Thus, IHAT should be considered of value in survey study on infections of rodents with these parasites