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A laboratory experiment was carried out at Seed Technology Research Unit at Mansoura, Dakahlia Governorate, Field Crops Research Institute, Agricultural Research Center, Egypt, to evaluate the effect of storage methods (normal storage in cotton bags and sealing storage in plastic jars and metal packages) and fumigation with phosphine at 0, 3, 5 and 7 tablets/m3 on storage efficacy, germination and seedlings parameters of wheat during different storage periods (3, 6 and 9 months after harvesting). The most important results can be summarized as follows:- Increasing storage periods of wheat seed from 3 to 6 and 9 months significantly affected storage efficacy characters (insect infestation and weight loss percentages), final germination percentage and seedling parameters (seedling length, root length, shoot length and seedlings fresh and dry weights). - The best results of storage efficacy of wheat recorded when sealed stored in metal packages, followed sealed stored in plastic jars and lastly in cotton bags. Whereas, highest germination and seedling parameters were recorded when sealed stored in metal packages, followed by normal stored in cotton bags and lastly stored in plastic jars. - The lowest percentages of insect infestation and weight loss in wheat seeds were obtained from fumigation with phosphine at the rate of 7 tablets/m3. While, maximum values of germination and seedling parameters were obtained from fumigation with phosphine at the rate of 5 tablets/m3. This study recommended that fumigation wheat seeds before storage in metal packages with phosphine at the rate of 5 tablets/m3 under the environmental conditions of the experiment in Mansoura, Dakahlia Governorate, Egypt.

No doubt, double and triple infections are not uncommon features in some of the developing countries. In this paper, the effect of leishmanial infantum and schistosomal mansoni infection on the heart and lung of hamsters promoted many changes not seen in positive control with either parasite alone. Of these important changes, were the presence of leishmanial cardiac granulomas and earlier pulmonary granulomas in the lung were more or less the same as in positive schistosomal control. No doubt, with pulmonary schistosomiasis mansoni dangerous disease. Moreover, additional infection with pulmonary leishmaniasis increases the dramatic clinico-pathological picture.

In general, both Schistosoma mansoni and Leishmania, d. infantum affect more or less the same human organs. While the liver is the main organ affected, the intestine follows in importance. In the present study, L.d. infantum on tip of pre-existing S. mansoni in Syrian golden hamsters had delayed the appearance of both schistosomal and leishmanial granulomas in the intestine the positive control with either parasite alone. However, the leishmanial infection suppressed the schistosomal infection. Nevertheless, both types of granulomas caused shortening and broadening of the intestinal villi. The concomitant infection with leishmaniasis infantum and schistosomiasis mansoni promote the development of many pathological changes (liver, kidneys, intestine, blood picture etc.). No doubt, these changes lead to marked changes in the typical clinical picture of both parasites. Consequently, parasitological diagnosis of visceral leishmaniasis in concomitant infection is a must as in a case of VL. and HIV.

No doubt, double and triple infection in a patient is not an uncommon phenomenon in the Old World. Consequently, the histopathological picture of the liver of Syrian golden hamsters experimentally infected with Leishmania. d. infantum on top of pre-infection with S. mansoni was studied. The results showed that the liver was markedly affected by the concomitant infection than infection with either parasite alone. The superadded Leishmania infection caused the early appearance of cell necrosis and fatty changes. The schistosomal granulomas were rounded in shape and well circumscribed. However, they were smaller in size and less in number when compared with schistosomal control. Also, there was a comparative decrease in the number of their cellular constitutions but without changing in the cell types. The schistosomal granulomas were surrounded with a rim of amastigotes laden macrophages. On the other hand, the leishmanial granulomas, were irregular in shape but comparatively increased in size and in number on the behalf of the schistosomal granulomas. Their cellular constitutions comparatively increased as well. So, it is concluded that the L.d. infantum infection on the top of S. mansoni infection suppressed the schistosomal pathological picture in the liver of hamsters.

In Egypt, Schistosomiasis mansoni is one of the most important parasitic disease of man. Besides, in the last two decades, indigenous cases of infantile visceral leishmaniasis have been reported. These two parasites affect the kidney causing renal histopathological changes. Thus, it was aimed to study the concomitant infection of L. d. infantum on top of S. mansoni infection in Syrian golden hamsters, the model animal for both parasites. The results showed that the renal changes were more or less the same as infection with either parasite alone. Both parasites produce mesangial cell proliferation and mesangial matrix increase. Some glomeruli showed complete replacement of the capillary tuft with structureless homogenous material. In one S. mansoni positive control hamster Schistosoma eggs were seen within granulomas and atrophic glomeruli. However, the lesihmanial infection, more or less suppressed the schistosomal infection. The leishmanial infection itself became more prominent and the renal changes it caused appeared earlier and were more obvious.

In the 1980s, infantile visceral leishmaniasis was documented in Al Agamy (Alexandria). The causative agent is Leishmania d. infantum and the insect vector is Phlebotomus langeroni. In this paper, Syrian golden hamsters were chosen as a model animal for histopathological studies of L. d. infantum. Twenty four male hamsters were experimentally infected with L.d. infantum. Every week, two hamsters were sacrificed and parts from the liver, heart, lung, spleen, small intestine and kidney were paraffin sectioned and stained with haematoxylin and eosin or with Giemsa stain. The leishmanial granuloma was the main histopathological changes and the liver was the main organ affected. Leishmanial granulomas were common in the liver, but few in lung and small intestine. The hepatic granulomas increased in surface areas and in number in the late stage of the infection (6 weeks). They were formed mainly of histiocytes, less lymphocytes and very few eosinophils with necrosis inside and bridging in between granulomas mainly occurred in the late stage of infection. Neither fibrosis nor peripheral delimitation was seen. Kupffer cell hyperplasia was seen throughout the experimental period (12 weeks). The spleen showed expansion of the red pulp and atrophy of the white pulp. The kidney showed mesangial cell proliferation and the mesangial matrix increased accompanied with amyloid deposition. All the tissue sections were photographed and the results were discussed.

The electron microscopic structure of the detrusor muscle in schistosomiasis patients with poor bladder contractility as evaluated by urodynamic measures had been compared with normal detrusor muscle from non-schistosomiasis patients. In the patients with poor bladder contractility the detrusor was formed of muscle fibers which were smaller in size, widely separated by collagen and showed degenerative changes and hyalinosis. No evidence of smooth muscle hyperplasia, mitosis or fibroblastic proliferation was seen. This pathological changes in the bladder of schistosomiasis patients may explain the cause of poor contractility.

The immunoglobulins (IgG, IgM, IgE,IgA) and the complements (C3C4) were studied in hamsters as result of a single infection (S. mansoni or L.d. infantum) and as concomitant infection (L.d. infantum on top of S. mansoni). The immunological pattern showed profound IgG and IgA increase in the concomitant group than either infection alone. Also, concomitant infection induced more IgE increase than either infection alone. On the other hand, C3 and C4 showed more decrease in concomitant infection. The whole results were discussed.

A total of fifteen clinically and parasitologically proven adult cases of cutaneous leishmaniasis were studied for the demonstration of premalignant factor(s). The levels of antibodies against Leishmania parasite were measured with the indirect haemagglutination test (IHAT) and evaluated with the results of lymphoblast transformation test (LTT), a tumour suppressor gene (P53) and an asportic proteinase enzyme (Cathepsin D). Three patients (females) refused to be biopsied. The results showed a direct correlation between elevation of IHAT in 7/12 patients (Titers 1/128 to 1/512) and elevation of LTT in 7/12 patients (82 to 90%). On the other hand, two males with low (?) seropositive IHAT (1/64) and low LTT (2040%) gave positive P53 antibody and moderate (1) and marked (1) degrees Cathepsin D. So, it is concluded that cutaneous leishmaniasis infection particularly chronic one favours the premalignant changes in the granulomatous lesions.

The sera of 72 women with a history of abortion (sporadic or habitual abortion) or perinatal complications were examined for Toxoplasma antibodies using indirect immunofluorescent antibody test (IFAT). It was found that 27.8% of them were positive for toxoplasmosis with geometric mean titre of 1/64. Also sera of 34 women with normal obstetric history as a control group were examined. 11.8% of them were positive for toxoplasmosis with geometric mean titre 1/16. The difference between the control group and complicated group was found to be statistically significant. The histopathological picture of placenta of positive cases showed characteristics of toxoplasmic placentosis with detection of the organism in fixed paraffin sections using HX and E, PAS or Giemsa stains.

The present work is concerned with study of the effects of praziquantel, thiabendazole, mebendazole, cyclophosphamide and cortisone on histopathology of the small intestine (during intestinal phase) and skeletal muscles (during muscular phase), in addition to T. lymphocytes count and serum IgG estimation in experimental trichinosis in albino rats. Praziquantel has no effect on the histopathology of small intestine or skeletal muscles. Thiabendazole and mebendazole treatment resulted in complete eradication of Trichinella spiralis worms of small intestine and marked reduction of larval infection (mild infection) of skeletal muscle. Praziquantel, thiabendazole and mebendazole did not affect significantly the T. lymphocytes count of the host during the intestinal phase. Cyclophosphamide and cortisone suppressed the cellular immunity (T. lymphocytes) and accordingly enhanced the parasitic infection in histopathology of both phases. All the drugs tested induced significant reduction of T. lymphocytes in muscular phase (which may be due to parasitic infection itself) and insignificant effect on IgG level in both phases.

One hundred cases aged 4-20 years and suffering from chronic tonsillitis were examined for Toxoplasma antibodies using indirect immunofluorescent test (IFAT). It was found that 37% of them were positive for toxoplasmosis. 41.5% of hypertrophic cases and 32% of atrophic ones had toxoplasmosis but the difference was statistically insignificant. The mean antibody titres were higher in both atrophic and hypertrophic cases than in the control group. The patients aged from 11-20 years had a higher titre of Toxoplasma antibodies than those aged below ten years. Trials to detect tachyzoites, cysts or pseudocysts in fixed paraffin sections using HxE, PAS or Giemsa stains were not successful. The histopathological picture of tonsils removed from positive cases of toxoplasmosis showed characteristics of toxoplasmic lymphadenitis.