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We assessed the fate of beta-cyclodextrin, which is composed of seven alpha(1-->4)-linked glucose units in ring structure, in the human gastrointestinal tract. In four healthy ileostomists, ileal effluent was collected after oral administration of beta-cyclodextrin during fasting (10 g of beta-cyclodextrin) and postprandially (10 g of beta-cyclodextrin three times daily with meals). In 10 healthy volunteers, the amount of beta-cyclodextrin passing into the colon was determined by means of the breath hydrogen technique using lactulose as a standard, and stools were collected after oral administration of beta-cyclodextrin during fasting (10 g of beta-cyclodextrin) and postprandially (10 g of beta-cyclodextrin three times daily with meals). In ileostomists, we recovered from the small intestine 91 +/- 5% and 97 +/- 10% (mean +/- SD) of beta-cyclodextrin ingested during fasting and with meals, respectively. In healthy volunteers, H2 excretion in breath after beta-cyclodextrin ingestion was low compared with excretion after lactulose, but only traces of beta-cyclodextrin were recovered in stools. We conclude that beta-cyclodextrin is poorly hydrolyzed in the human small intestine but that it is fermented by the colonic flora with apparent minimal H2 production.

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We compared the effect of a standard oral rehydration solution and a high-sodium polymeric-glucose solution on sodium absorption in short-bowel syndrome. Six patients with high jejunostomy were tested in a random order with the standard solution or a solution containing maltodextrins (18 g Glucidex 12/L) enriched with 2.5 g NaCl/L. Solutions were administered via a nasogastric tube at a rate of 2 mL/min. Jejunal effluent was collected during an 8-h period. The net 8-h fluid absorption was not significantly different in the two periods. Glucose absorption was greater than 90% of the administered amount for both solutions. Net sodium absorption was greater for the maltodextrin solution than for the standard solution (56 +/- 12 vs 24 +/- 20 mmol, P less than 0.05). We conclude that replacement of glucose with maltodextrins and addition of sodium in the standard oral rehydration solution results in improved sodium absorption in short-bowel syndrome.

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The maltase (EC 3.2.1.20)/glucoamylase (EC 3.2.1.3) complex from rat small intestine brush border, which is able to split alpha (1----4) glucose-sorbitol linkage, was isolated and purified by chromatography on DEAE-Trisacryl M and Sepharose 6B. The complex was homogeneous on polyacrylamide gel electrophoresis. Kinetic parameters were studied on two substrates: maltose and maltitol (Km:1.3 mM and 30 mM, Vmax:200 nmol X min-1 and 15 nmol X min-1, respectively). Inhibition studies were performed with maltose and maltitol as substrates and isomaltitol and delta-gluconolactone as inhibitors. Crossed-inhibition reactions were also performed. The results support the existence of one single catalytic site and this fact was confirmed by physicochemical properties. Similar results were obtained with germ-free rats as well as with conventional rats adapted over 6-12 months to Lycasin 80/55 as the sole source of sugar. Lycasin 80/55, hydrogenated starch hydrolysate, was converted by purified maltase/glucoamylase complex in glucose and sorbitol.

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Intravenous inoculation of "young" bacilli of Calmette-Guérin 14 days before challenge with Schistosoma mansoni highly protect the mice against this infection.

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Various antigens interacting specifically with IgE antibodies from infected humans were identified in S. mansoni, F. hepatica and E. granulosus soluble extracts by means of radioimmunoelectrophoresis. Two allergens common to adult worm and cercariae were identified in S. mansoni extracts. They proved to be distinct from genus--or species--specific antigens previously identified in the parasite. In adult F. hepatica extract a species-specific antigen and another lipoprotein were shown to interact with IgE antibodies of patients with fasciolasis. Two major allergens were also found in whole fluid of sheep E. granulosus cysts. One of them corresponded to Echinococcus genus specific antigen. These results are discussed according to immunological findings in parasitic infections.

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Schistosomicide drugs are used as ligands to isolate the target antigens of schistosome by affinity chromatography. Anti-target antigens immune sera produced in rabbit permit their localization on the parasite using immunofluorescence. Target antigens of some drugs determine a relatively high immunoprotection in rat or mouse schistosomiasis infection.

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