Maximum activities of some key enzymes of glucose metabolism in livers of schistosoma mansoni infected mice

The effects of infection with Schistosoma mansoni [Saudi strain] on the maximal activities of glucose utilization pathways were studied in livers of mice during 16 weeks post-infection. The maximal activities of 6-phosphofructokinase and pyruvate kinase were significantly increased from week 4 indicating the increased capacity of the liver to utilize glucose, whereas the activity of glycogen phosphorylase was decreased as early as week 2, suggesting diminished hepatic glycogen break-down. Glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were significantly decreased from week 2 and 4, respectively. This suggested decreased flux through the pentose phosphate pathway in livers of infected animals. A significant decrease in the activities of citrate synthase and oxoglutarate dehydrogenase was observed at week 10 and 6, respectively, indicating diminished maximal capacity of the Kreb's cycle. All enzymatic changes [except Kreb's cycle enzymes] were detected prior to egg deposition [2-4 weeks] and are related, therefore, to the toxic products of growing worms. Such changes became more evident following egg deposition. Hepatic necrosis was observed at week 4 prior to egg deposition, which provides further evidence that factors released by worms can adversely affect the hepatic parenchyma. Necrosis, however, became more marked with the onset of egg deposition. The significance of these enzymatic changes, pathological findings and the underlying mechanisms are discussed

Schistosoma mansoni: tegumental surface alterations following oxamniquine treatment of infected mice [Sup]

The in vivo effects of oxamniquine on the tegumental surface of adult Schistosoma mansoni were studied using scanning electron microscopy. Pronounced tegumental alterations were observed in all worms including marked edema, wrinkling and distortion, atrophy, loss of tone and complete disorganization of suckers, blebbing, destruction of tubercles, collapse of sensory papillae and erosion or peeling of the surface layer. The amount of damage was more marked in males than females and varied considerably among worms recovered from the same host and even in different regions of the same worm. Damage was irreversible and all worms were eventually eliminated

Experimental schistosomiasis mansoni: electro-phonetic studies on serum proteins before and after administration of oxamniquine

By means of electrophoresis quantitative estimation of serum protein components were made at various intervals before and after treatment with oxamniquine. During infection of mice with S. mansoni serum protein fractions showed marked alterations. Significant increase of total protein, alpha-2 globulin and beta globulin started at week 4 and alpha-1 globulin and gamma globulin at week 6. The significant decrease of globulins at week 6 resulted in reduced albumin globulin ratios. Some of these changes developed during maturation of worms and became more evident with initiation of egg deposition. The possible cause of these variations and their significance was discussed. Oxamniquine treatment of the drug to normal was followed by temporary increase of serum albumin

Effect of schistosomiasis mansoni on open-field exploratory behaviour in mice

The response of mice infected with Schistosoma mansoni to a novel environment has been investigated in an attempt to study the effects of the disease on brain cognitive function by using Opto-Varimix instrument and Autotrack computer program. Two to 18 weeks infected mice showed lower ambulatory activities than their matched controls with the largest reduction occurring between weeks 6 to 10. Maximum effects were observed in week 8. The first 5 minutes of ambulatory activities, designated as the "first session", were 22.5% lower in infected mice as compared with controls. The decline in the first session activities of infected mice was slower than the controls. Infected mice showed fewer stereotype movements with maximum reduction in week 16 of infection. There was no correlation between mice ambulatory activities or stereotype movements and infection duration. The importance of these findings in relation to the course of the disease and the underlying mechanism[s] are discussed

Effect of ultra-violet irradiation on the ocystic zygotes of eimeria stiedae

Irradiation proved to be lethal to the zygotes as indicated by failure of maturation of irradiated oocysts on subsequent culturing in potassium dichromate solution. Prolonged irradiation led to apparent degenerative changes which involved the zygote as well as the cyst wall

Treatment of hepatic coccidiosis in rabbits by tinidazole

A single oral dose of 100 mg tinidazole resulted in a cure rate of 40% of rabbits infected with Eimeria stiedae. Repetition of this dose for 2 or 3 successive days led to a 100% cure rate. No side-effects could be observed even with repeated doses