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The effects of soluble extracts of Ascaris suum on human blood coagulation were investigated. Whole worm supernatant solution prolonged the whole blood clotting time and the kaolin-activated, partial thromboplastin time but it did not alter the prothrombin time. These data indicate impairment of the intrinsic pathway of blood coagulation. Whole worm supernate inhibited platelet aggregation induced by ADP and ristocetin. This supernate did not affect fibrinolysis. The maximal concentration of anticoagulant activity was found in the pseudocoelomic fluid of the worm. Activity was also noted in the cuticle and secretory/excretory products. Perhaps inhibition of blood clotting by helminths may facilitate their passage through the blood stream.

Calmodulin was purified from the obliquely striated skeletal muscle of Ascaris suum. The calmodulin had a molecular weight of 16,400 and the amino acid composition indicated it is highly similar to other purified calmodulins, showing insignificant variation in 12 of 17 residues. In the residues that showed variation, a trend towards conservative substitution was observed. Spectrophotometric absorption maxima of 276 nm and 283 nm were observed. A molar absorption coefficient of 7,800 was calculated. Calcium-dependent binding to phenothiazine Affi-Gel confirmed that calcium binding induces conformation changes characteristic of calmodulin. Double reciprocal analysis of phosphodiesterase activation by A. suum calmodulin gave a Kapp of 40 nM.

The effect of in vivo treatment with mebendazole on the ultrastructural morphology of Ascaris suum intestine was investigated. Pigs, infected with A. suum, were fed ad libitum a medicated food containing mebendazole at a concentration of 30 ppm. Control and treated animals were killed 6, 9, 15, and 24 hr after the onset of feeding. The parasites were quickly collected from the pig intestinal tract and prepared for ultrastructural and cytochemical examination. Absence of secretory granules in the terminal web, accumulation of secretory granules in the Golgi region, formation of autophagic vacuoles in the apical cell part, and loss of glycogen were the characteristic changes observed after 6 and 9 hr of treatment. Degenerative changes were very pronounced after 15 and 24 hr and involved almost the entire cytoplasm. Microvilli were decreased in number and appeared swollen in the majority of absorptive cells. Some more severely altered cells were completely devoid of microvilli. Cytochemistry revealed that the accumulated secretory granules in the Golgi area contained glycoproteins or polysaccharides. Microvilli, lysosomes, and Golgi apparatus were reactive for acid phosphatase in the control intestinal cells. After treatment, the enzyme activity was localized in numerous autophagic vacuoles, whereas the secretory granules remained unstained. The acid phosphatase activity in the microvilli decreased or was completely absent. The possible significance of these modifications in view of mebendazole's anthelmintic activity is discussed.

Representative facultative anaerobes of the bacterial flora from the intestine of female Ascaris suum were isolated and identified. The number of bacteria in the intestine was approximately 4 X 10(9) per g wet weight of intestine. Seventeen of 19 of the isolated colonies were found to secrete 5-hydroxytryptamine in culture. Holding A. suum in an antibiotic-containing medium did not affect the levels of 5-hydroxytryptamine in the worm, which were 231 +/- 14 ng/g in antibiotic-media as compared to 250 +/- 16 ng/g in control media. This implied that the bacteria may not be contributing to the level of 5-hydroxytryptamine in the tissues of A. suum.