An experimental vaccine providing heterologous protection for Leishmania species in murine model.

Five groups each of 20 BALB/C mice were immunized by heat killed L. donovani promastigotes. Two groups served as control. Each group of mice was subdivided into 2 equal subgroups and challenged with either L. donovani or L. major. The results revealed a high cross reactivity paralleled by a high cross protection between L. donovani and L. major. Heat killed L. donovani promastigotes super-passed other tested SDS-PAGE fractionated and eluted L. d. fractions identified by immune BALB/c mice in providing protection against both L. donovani and L. major. The percentage of protection (reduction in parasite burden) offered by each vaccine was as follows: 80.21%, 36.11%, 9.29%, 33.44% and 17.48% respectively against challenge infection with L. donovani and 3.012 x 10(4), 1.095 x 10(4), 6.054 x 10(2), 2.409 x 10(4), and 3.34 x 10(2), respectively against challenge infection with L. major.

Variations of direct fluorescent antibody test and serum bile acids levels following praziquantel treatment in Schistosoma mansoni experimentally infected mice.

This study was performed to evaluate the efficiency and use of an immunopathological test viz "Direct Fluorescent Antibody Test (DFAT) for detection of IgG and IgM deposits in liver and kidney biopsies" and a biochemical test viz "estimation of serum bile acids by enzymatic colorimetric technique" for follow up Schistosoma mansoni infection using Swiss albino mice. Test were done during infection and after Praziquantel (PZQ) treatment. Mice were classified according to the duration of infection and post-therapy periods. It was found that both tests should be used together to provide good parameters to demonstrate S. mansoni infection and to test the regression of the disease after treatment.

Immune complexes as monitors of cure in Schistosoma mansoni infected mice.

This study was done to assess the use of immune complexes estimated by micro-ELISA as monitors of cure of schistosomiasis mansoni experimentally infected Swiss albino mice which received praziquantel (PZQ) treatment. They were grouped according to duration of infection (4, 8, 12, 16w) and then subgrouped owing to post-treatment life span (4, 6, 8w). It was found that the changes observed in serum level of immune complexes (IC) would provide a good parameter to demonstrate the severity of infection and being an indication of improvement after treatment. The recorded changes confirmed the relationship between schistosomal hepatic affection and serum levels of IC. The study showed the potent anti-schistosomal effect of PZQ. It cured completely when it was given early after infection or improved moderately when given late.

Effect of praziquantel treatment on hepatic pathology of Schistosoma mansoni experimentally infected mice.

In this study we used Schistosoma mansoni (S. mansoni) infected mice were used to assess the pathological changes in the liver at various stages of the disease as well as the effectiveness of Praziquantel (PZQ) treatment on hepatic pathology also at different stages. The S. mansoni infected mice were divided into 7 groups and subgroups according to post infection and/or post treatment periods. The various hepatic pathological changes were recorded and it was concluded that PZQ is an effective yet, safe non hepatotoxic drug and that the earlier the application of treatment in the course of the disease the better cure we can get with minimal or no insult to the liver tissue.

Parasitic infections associated with malignancy and leprosy.

Results of parasitic infections, as revealed by urine and stool examination was significant (P less than 0.05) in 43.3% of patients suffering from different malignant diseases and non significant (P greater than 0.05) in 29.3% of leprosy patients compared to 22% in control subjects. The most prevalent parasites were E. histolytica and G. lamblia. Cryptosporidium occysts were not detected. By stool examination and culture, S. stercoralis larvae were detected only in the malignancy group. The most common parasites occurring concomitantly were A. duodenale and S. stercoralis. By the IFAT, strongyloidiasis gave significantly higher positive results in the malignancy group than in the leprosy and control groups. IFAT for toxocariasis, showed highly significant positivity in the leprosy group and significantly positivity in the malignancy group. For toxoplasmosis, it showed highly significant positive results in both leprosy and malignancy groups. Eosinophilia was significantly more prominent among malignancy patients and insignificant among those with leprosy. Parasitic infection detected by urine and stool examination among patients with eosinophilia was found in 76% of the malignancy patients and in 66.7% of the leprosy patients.

Circulating immune complex in bilharzial arthropathy.

Using the enzyme-linked immunosorbent assay (ELISA), the immune complex (IC) level was estimated in sera of 100 individuals grouped as follows; Group 1: 40 cases with bilharzial arthropathy. Group II: 20 cases with bilharziasis. Group III: 20 cases with rheumatoid arthritis. Group IV: 20 apparently healthy individuals. IC level was also estimated in synovial fluid of 4 cases with knee joint effusion. A significant increase in IC level in cases with bilharzial infection (with or without arthropathy) was noticed. This was higher in intestinal than in urinary bilharziasis. Further more IC level was significantly higher in cases of bilharzial arthropathy than in cases with bilharziasis alone. The IC level in synovial fluid was higher than in serum with a positive correlation. The role of IC as a causative agent in the pathogenesis of bilharzial arthropathy is clearly discussed.

Parasitic infections associated with mental retardation in Egypt.

Examination of 150 mentally retarded patients for parasitic infections by urine and stool analysis revealed that 115 (76.67%) were positive. The most prevalent parasites found were T. trichiura in 56%, A. lumbricoides in 40.6% and A. duodenale in 21.33%. Double infection was present in 30.67%, triple infection in 15.33% and quadriple infection in 6%. Eosinophilia was detected in 91 (64.08%) of 142 examined cases, all were suffering from intestinal parasites. S. stercoralis was present in 11.33% by stool examination and culture and in 24 (60%) out of 40 examined cases by the IFAT. Toxocara antibodies were present in 38 (56.72%) out of 67 examined cases by the IFAT. Toxoplasma antibodies were present in 106 (74.65%) out of 142 examined cases by the IFAT.

Immunodiagnostics of Toxocara canis in suspected ocular and visceral manifestations.

Sera from patients with ocular and visceral manifestations of toxocariasis were tested by precipitin absorption (PAT), counter-immunoelectrophoresis (CIEP), indirect fluorescent antibody (IFAT) and ELISA. The ocular cases revealed a percentage of positivity of 36% by PAT, 0% by CIEP, 32% and 28% by IFAT with embryonated egg (EE) and frozen section antigens (FS) respectively and 40% by ELISA. The visceral cases revealed 44% positively by PAT, 24% by CIEP 52% and 48% by IFAT with EE and FS respectively and 52% by ELISA. Statistical evaluation was done to interpret the results.

Immunodiagnostics of visceral toxocariasis.

Twenty five suspected cases of visceral toxocariasis and 25 apparently healthy controls, were tested in four serological tests, namely precipitin absorption test (PAT), counter immunoelectrophoresis (CIEP), indirect fluorescent antibody test (IFAT), and enzyme linked immunosorbent assay (ELISA). Adult Toxocara worm antigen was used in PAT & CIEP as saline extract and as frozen sections (FS) in IFAT while the embryonated eggs (EE) were used as saline extract in ELISA and as a whole in IFAT. The percentages of positivity reported were 44% by PAT, 24% with CIEP, 52% with IFAT (EE), 48% with IFAT (FS), and 52% in the ELISA. In the apparently healthy control group, only one subject gave positive result with PAT, and ELISA at titres of 1/16 and 1/64 respectively. The EE antigen proved to be more sensitive than adult worm antigen, where it was used in IFAT & ELISA and gave the highest percentage of positivity and the highest titre (1/256 & 1/4096 respectively). It was noticed that the children below the age of 10 years, were statistically significant (P less than 0.05) by all tests except CIEP.

Some aspects of sandflies of the genus Phlebotomus in El Agamy, Alexandria.

Leishmaniasis presents a health problem in several countries of the old world. Cutaneous and now visceral leishmaniasis have been reported in Egypt. Visceral leishmaniasis has been reported in El Agamy, Alexandria. In this paper, the seasonal and daily hours of activities of both P. papatasi and P. langeroni as well as the blood preference were studied over two successive years. The results showed a bi-model or two peaks a year. The sandflies started to appear in the last of March or beginning of April and ended in last of November or beginning of December. The indoor hours of activity standard earlier and ended later than the outdoors one. The blood of the females of P. papatasi was mainly human blood, while that of P. langeroni was mainly non-human blood.

Relationship between schistosomiasis and arthropathy.

This study was carried out to suggest criteria for diagnosing arthritis associated with schistosomiasis. 180 cases were classified into three clinical groups, 120 schistosomal arthritic group (I), 20 schistosomal non-arthritic (II), 20 arthritic non-schistosomal (III) and 20 controls (IV). Four tests were done to exclude other causes of arthritis namely, Erythrocyte sedimentation rate (ESR), Rose-Waaler test (RW) for rheumatoid factor (RF), antinuclear antibody test (ANA) and determination of serum uric acid (SUA) level. A history, clinical examination, urine and stool examination, intradermal test (IDT), indirect haemagglutination test (IHAT), circumoval precipitin test (COPT) and complete blood picture, were performed for all groups. 20 patients were selected randomly from group I and received praziquantel to be followed up 6 months later. Bilharzial ova were found in the excreta of group I and II. The percentage of positive IDT, IHAT and COPT in I & II was 90.8%, 90%, 88.3% and 85% respectively. Blood picture showed mild anaemia and from low to moderate eosinophilia. ESR was moderately raised. RF positivity was 6.6%, 10%, 65% and 5% in the four groups respectively. ANA positivity was 1.6%, 0%, 50% and 0% respectively. There was a marked improvement of arthritic manifestations after praziquantel in 90% of cases.

Studies on biting midges of the genus Culicoides in the Suez Canal Zone.

The importance of the biting midges of the genus Culicoides being in their role as vector of non periodic filarial worms of the genus Mansonella and Dipetalonema to man and pathogenic virus to livestock. Besides, their painful bite may disappear within an hour or cause an appreciable systemic reaction. In this paper, the four species recorded in the Suez Canal Zone (C. schultzei, C. puncticollis, C. pallidipennis & C. distinctipennis) were redescribed. Also, the hours of activity of the most common and abundant species, C. schultzei was studied. C. neavei Austin, 1912, representing a new record in Egypt.