Comparative study between non lethal and lethal strains of Plasmodium yoelii with reference to its immunological aspect

Innate immunity has an important role in the protection against malaria. To clarify the effect on non lethal and lethal strain of Plasmodium yoelii, comparison between two groups of C57BL/6 mice infected with 10[4] parasitized RBCs was performed. Liver and spleen mononuclear cells were isolated and analyzed by flow cytometry. The parasite appeared in blood on day 3 in both strains, with non lethal infection parasitemia reached a peak of 60% on day 14 and mice completely recovered, while in lethal infection parasitemia was 80% on day 7 and mice succumbed to death. In non lethal strain, mice became anemic and the hematocrit percentage returned to its normal value during recovery, while in the lethal strain mice were severely anemic before death. The major expanding cells were found to be TCR Intermediate [TCR[int]] cells, mainly NK1.1 subset, these TCR[int] cells were distinguished from conventional T cells of thymic origin. CD4[-] and CD8[-] cells increased in both strains. During malarial infection, the population of conventional T cells did not increase and usually associated with thymic atrophy. The present results showed that TCR[int] cells were intimately associated with the protection against malarial infection in both non lethal and lethal strains but the mice died in lethal infection due to the massive destruction of red blood cells leading to fatal anemia

Comparative morphological studies on three sarcocystis species in Sohag, Egypt

Samples from the tongue, heart, oesophageal and skeletal muscles were collected from 100 cow and 100 buffalo from Sohag slaughterhouses. Macroscopic examination for sarcocysts was followed by microscopic ones on impression smears and compressed muscles. Histological sections and transmission electron microscope [TEM] studies were done on positive cases. Sarcocystis infection rate of cows were 84%. Two species of Sarcocystis were detected: 1-S. cruzi with a membrane provided with hairlike villar protrusions folded over the surface of the cyst. These protrusions were rod-like, round, oval or irregular in shape and were approximately parallel to the cyst surface. 2-S. hominis characterized by a cyst wall consisting of cylindrical finger-like villar protrusions and having microfilaments. The protrusions were perpendicular on the cyst surface with broad tips and contain microfilaments. Buffaloes' muscle, samples revealed an infection rate of 28%. The macroscopic fusiform-shaped species only was detected [Sarcocystis fusiformis]. The role of cyst wall ultrastructure and thickness were discussed regarding identification and pathogenicity

Light microscopic study of the effect of flubendazole, praziquantel and combination of both drugs on adult schistosoma mansoni [with 14 figures]

It is considered that combination of chemotherapy with other control measures can reduce transmission and morbidity of schistosomiasis. This study was done using 60 albino mice infected with cercariae of Schistosoma mansoni. Mice were divided into 4 groups [control, flubendazole treated, praziquantel treated and combination of both drugs]. The effect of treatment was evaluated on male and female worms after [1, 2 and 3 Week Post Treatment]. Worms were collected by perfusion of portal vein and mesenteric veins separately, stained with acetic acid alum carmine and examined by light microscope

Scanning electron microscopy of adult schistosoma mansoni after treatment with praziquantel, flubendazol and combination of both [with 4 plates]

Many antischistosomal drugs are known to cause changes in the ultrastructure of adult worms. This study was done using 60 albino mice infected with cercariae of Schistosoma mansoni. Mice were divided into 4 groups [Control, Flubendazole-treated, Praziquantel-treated and the last group treated by combination of both drugs]. The effect of treatment was evaluated on male and female worms after one and three weeks post treatment. Worms were collected by perfusion of portal vein and mesenteric vein separately then examined by scanning electron microscopy

Evaluation of some serological tests in diagnosis of toxoplasmosis among complicated pregnancy

Toxoplasmosis is one of the common public health problems. The congenital infection is the most serious form of the disease. This work was conducted on 100 serum samples of pregnant women with previous complicated obstetric history suggesting Toxoplasma infection. Anti-Toxoplasma IgG and, IgM antibodies were evaluated using four commercial serological tests: Latex agglutination, IHAT, ELISA and Immuno-Comb test. The results of the study proved that Latex test gave the highest percentage of seropositivity [58.3%], followed by IgG ELISA [55.8%] and Immuno-comb [55%], while IHAT gave a positive result of [50%]. IgM seropositivity was [44.1%] by ELISA and [46.6%] by Immuno-comb. The correlation between all tests was significant

Parasitological and histopathological studies on intestinal coccidian parasities in immunosuppressed mice.

Immunosuppression of 24 clean laboratory albino mice treated with cortisone induced infection by three intestinal coccidian parasites, Cryptosporidium [muris and parvum],Microsporidia and Isospora sp. These parasites were detected in stool smears, intestinal scraping smears and intestinal tissue sections of immunosuppressed mice at intervals. Modified Ziehl-Neelsen and Giemsa stains were used for staining of smears. Intestinal tissue sections were stained with hematoxylin and eosin, modified ZN and alcian yellow toluidine blue. It was found that the modified ZN stain is the best one for the diagnosis of these coccidian parasites in stool smears and in tissue sections. Alcian yellow toluidine blue stain was useful in tissue sections because it provided excellent contrast and stained the organisms with a blue color against a yellow background. Histopathological changes in the intestinal tissues caused by these coccidian parasites were fully described

use of three Ascarid antigens in serodiagnosis of visceral larva migrans in clinically suspected patients

The syndrome of visceral larva migrans [VLM] is a zoonotic disease caused by migration of nematode larvae especially ascarids in human tissues. In the present study serum samples of 40 clinically suspected patients of VLM with persistent unexplained eosinophilia were tested by ELISA IgG and Western-immunoblotting assays for antibodies of three ascarids [Parascaris equorum, Toxocara vitulorum and Toxascaris leonina]. Embryonated egg extract antigens of these ascarids were used for serodiagnosis. By ELISA test the percentage of positivity was 42.5 percent with P.equorum, 40 percent with T.vitulorum and 30 percent with T.leonina antigens. By Western-blot assay, the seropositivity was 42.5 percent with P.equorum and 25 percent with T.vitulorum antigens. 27.5 percent of tested sera reacted with T.leonina antigen and showed single band at 65 KDa. This band was previously proven to be specific for Toxocara canis infection only. Some cases showed seropositivity for two or three species of ascarid antigens. The relationship between the seropositivity, clinical symptoms, eosinophilia and age groups was discussed. The use of two immunological assays and three types of ascarid antigens in the present study revealed for the first time the role of P.equorum and Toxocara vitulorum as causative agents of human VLM in Upper Egypt

Intestinal protozoal infection in immunocompromised children in Assiut with special referrence to cryptosporidiosis

Examination of one hundred stool samples collected from immunocompromised children for intestinal protozoal parasitic infection revealed that twenty-six cases were positive. The most commonly detected parasite was Giardia lamblia [21%]. Cryptosporidium oocysts were found in 3%, Entamoeba histolytica in 3% and E. coli in 3%. Chilomastix mesnili was found in 2% and Trichomonas hominis in 1% of the cases. Mixed infections were detected in 6%. The opportunistic character of Cryptosporidium and non-opportunistic habits of other intestinal protozoa encountered were discussed