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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of acarbose on hydrolysis of a pure starch meal was investigated in normal subjects and ileostomy patients by means of 13CO2 breath tests and blood glucose levels as parameters of absorption, and of H2 breath tests, serum acetate levels, and ileal loss of carbohydrate as parameters of malabsorption. Additional information on the effect of acarbose on alpha-amylase activity was obtained by in vitro experiments. Acarbose (200 and 400 mg) significantly delayed starch absorption. Serum acetate was found to be a less sensitive marker of malabsorption than breath H2 excretion. After intake of 50 g starch plus 400 mg acarbose, 23-71% of the starch load was lost in the ileostomy effluent, for a large part as starch. This suggests that acarbose considerably inhibits alpha-amylase, and not only brush-border enzymes. In vitro experiments confirm that an inhibition of two thirds of alpha-amylase activity can be expected from pharmacologically used doses of acarbose.
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PMID:Effects of acarbose on starch hydrolysis. Study in healthy subjects, ileostomy patients, and in vitro. 161 53

The influence of hydrolysis on the assimilation rate of important nutritional carbohydrates was studied in healthy subjects and patients with intestinal diseases, mainly by means of 13CO2 breath test techniques. All substrates were "naturally enriched" with carbon-13. The studies showed that hydrolysis is the rate limiting step for the assimilation of lactose, starch and even maltose, but not for the assimilation of sucrose. The degree of gelatinisation and the degree of side-branching of starch molecules were two important parameters, influencing starch hydrolysis in normal subjects. Addition of wheat bran had no influence on the digestion rate of starch. A comparative study between normal subjects and patients with pancreatic disease, showed that starch digestion may be impaired in patients with pancreatic disease. However, this occurs only if amylase output is extremely low. The effect of lactase deficiency on lactose absorption was studied in patients with a history suggestive of lactase deficiency. For this purpose a lactose 13CO2 and H2 breath test were compared with lactase activity in a jejunal biopsy. The results showed that the relation between lactase activity in the biopsy and lactose assimilation takes the form of a saturation curve. The 13CO2 breath test was found to be a reliable test for the diagnosis of lactase deficiency. Finally, the effect of acarbose on starch digestion was studied in normal subjects, ileostomy patients, and a fecal incubation system. These experiments showed that acarbose may induce an important degree of starch malabsorption. If administered in high doses, the effect is not only related to inhibition of brush border enzymes, but also to the inhibition of alpha-amylase.
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PMID:Georges Brohee Prize 1988-1989. Assimilation of nutritional carbohydrates: influence of hydrolysis. 205 48

The material comprises 25 patients with gluten-induced enteropathy and 16 patients with various intestinal disorders. The intestinal contents were aspirated in four subsequent periods of 20 minutes each after ingestion of a standard meal. The volume, pH, and the concentration of alpha-amylase, trypsin, chymotrypsin, and lipase were determined in the collections. Only minor deviations from normal pH-levels were observed. In both groups of patients, the secretion of lipase, and to a minor degree that of amylase, were more markedly reduced than the secretion of the proteolytic enzymes. With the exception of the values of trypsin, concentrations of enzymes were seen to be below the lowest normal value in approximately one-third of the patients throughout the period of digestion. It is concluded that the pancreatic function was genuinely reduced in several patients with enterogenous malabsorption. It may be explained as an unspecific effect of the malabsorption.
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PMID:pH and concentration of pancreatic enzymes in aspirates from the human duodenum during digestion of a standard meal in patients with intestinal disorders. 2018 73