ABSTRACT
DEET (N, N-diethyl-m-toluamide) is one of the reliable and most widely used insect repellents. The present work was planed to evaluate the effect of free DEET, controlled release DEET and white precipitate ointment on the viability of cercariae of S. mansoni in-vitro. They were also topically applied to mice to study their efficiency in preventing cercarial skin penetration. Free DEET and controlled release DEET formula caused immobilization and death of cercariae within twenty and five minutes respectively. The number of adults detected after application of free DEET and white precipitate ointment to mice skin prior to infection were significantly lower than the control group. When controlled release DEET was applied no adults could be detected indicating failure of cercariae to enter through the skin. This was confirmed by histopathological study of the liver which was free of granuloma. Scanning electron microscopy revealed tegumental changes in cercariae exposed to both free DEET and controlled released DEET. So, topical application of any of the three chemicals was effective in controlling S. mansoni infection. The best was with controlled release DEET.
Subject(s)
DEET/pharmacology , Schistosoma mansoni/drug effects , Schistosomiasis mansoni/prevention & control , Administration, Topical , Animals , DEET/administration & dosage , Delayed-Action Preparations , Mice , Ointments/administration & dosage , Ointments/pharmacology , Schistosoma mansoni/growth & development , Schistosomiasis mansoni/parasitologyABSTRACT
Out of 23 symptomatic cases 21 specimens were positive for T. vaginalis by one or more methods. 21 were positive by PCR (91.3%) and 17 (72.9%) by culture, 14 (60.8%) by Acridine orange (AO) stain and 13 (56.5%) by wet mount microscopy. The PCR detected all the positive cases and no PCR negative cases proved to be positive by any other technique. So, it is the test of choice for diagnosis of trichomoniasis. The modified Diamond's media proved to be highly sensitive (80.95%) and the results of the culture were significantly associated with those of PCR. The results of both wet mount and AO stain were insignificantly associated. The wet mount although widely used, easy, rapid and inexpensive yet, it has low sensitivity. So, negative cases should be repeated by either culture or PCR.
Subject(s)
Trichomonas Vaginitis/parasitology , Trichomonas vaginalis/growth & development , Vagina/parasitology , Adolescent , Adult , Animals , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Electrophoresis, Agar Gel/methods , Female , Humans , Middle Aged , Polymerase Chain Reaction/methods , Trichomonas vaginalis/geneticsABSTRACT
The present work was designed to assess the effect of different degrees of temperature and salinity on the viability and infectivity of G. lamblia and C. parvum at different storage time. The results revealed that boiling of protozoa for one minute minimized their viability to less than 1% and rendered them non-infectious, while exposure to 4 degrees C and -4 degrees C up to seven days preserved their viability and infectivity. Whereas it was found that salinity was effective at high concentration (50 ppt) or for long storage time at lower concentrations.
Subject(s)
Cryptosporidium parvum/pathogenicity , Giardia lamblia/pathogenicity , Sodium Chloride/metabolism , Temperature , Animals , Cryptosporidiosis/parasitology , Cryptosporidium parvum/growth & development , Cryptosporidium parvum/metabolism , Dose-Response Relationship, Drug , Egypt , Feces/parasitology , Giardia lamblia/growth & development , Giardia lamblia/metabolism , Giardiasis/parasitology , Humans , Mice , Rats , Sodium Chloride/administration & dosage , Time FactorsABSTRACT
Different types of Toxoplasma gondii vaccines were evaluated using parasitological and histopathological means to induce immunity in Swiss pregnant mice and their pups against the challenge with virulent RH strain. Immunization was performed before mating by using live cyst vaccines (LCV), LCV-IL-2 combination, irradiated cyst vaccine (ICV) and ICV-IL-2 combination. It was demonstrated that pre-immunization with the current vaccines offered significant protection of both dams and pups. The highest level of protection was noticed in mice which received LCV-IL-2, followed by ICV-IL-2, then LCV and the least protection was elicited in dams immunized with ICV alone. The results threw light on the possibility of applying such vaccines not only in mice but also in other mammalian hosts including human.
Subject(s)
Infectious Disease Transmission, Vertical/prevention & control , Protozoan Vaccines , Toxoplasma/immunology , Toxoplasmosis, Congenital/prevention & control , Vaccination , Animals , Animals, Newborn/immunology , Disease Models, Animal , Female , Lethal Dose 50 , Mice , Pregnancy , Pregnancy Complications, Parasitic/prevention & control , Toxoplasma/pathogenicity , Toxoplasmosis, Congenital/transmission , VirulenceABSTRACT
Bivalves are filter feeders concentrating pathogens from waters and are often eaten raw. Two species, Caelatura Iaronia pruneri and Donax trunculus limiacus commonly known as Gandofli and Om el Kholool respectively were examined. Shellfish were collected from markets in Alexandria to detect any human pathogenic protozoa in them. The infectivity of the detected protozoa was studied by experimental animal inoculation. The results revealed the presence of infectious Cryptosporidia oocysts and Microsporidia spores in both bivalves. Cyclospora sp. was detected only in Gandofli but was non-infectious to mice. There is a potential risk of acquiring protozoa infections if shellfish are eaten raw or insufficiently cooked.
