Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bacterial extracts were prepared from cultures originating in chronic self-filling intestinal blind loops in rats. Their ability to remove active maltase molecules from isolated brush border membranes was studied in vitro. Twelve strains in 51 tested, belonging to one of three species, Bacteroides fragilis, Clostridium perfringens, and Streptococcus fecalis, possessed maltase-releasing activity. The ability to remove maltase correlated well with the ability to hydrolyze p-nitrophenyl-tert-butyloxycarbonyl-l-alaninate (NBA), an ester substrate rapidly hydrolyzed by elastase, but not with substrated favored by tryhsin and chymotrypsin. Maltase-releasing activity from C. perfringens was strongly inhibited by soybean trypsin inhibitor and to a lesser extent by lima bean trypsin inhibitor. Of four chloromethylketone active-site directed inhibitors tested with specificities for elastase, trypsin, and chymotrypsin, inhibition was maximal with elastase-specific inhibitors. In two species, activity was shown to be heat sensitive, and to be inhibited by concentration of the extract. In one species maltase-releasing activity was shown to be due to an enzyme of molecular weight at least 66,000 with the capacity to remove lactase, sucrase, and alkaline phosphatase, as well as maltase. The results indicate that anaerobic or facultatively anaerobic species, previously identified with the pathology of of the blind loop syndrome, contain proteases which are capable of removing components of the intestinal surface membrane. These proteases appear to have elastase-like substrate specificity and may be involved in the etiology of disaccharidase deficiency in bacterial overgrowth syndromes.
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PMID:Pathogenesis of mucosal injury in the blind loop syndrome. 35

7 infants, aged 5 weeks to 11 months, with clinically documented intolerance to cow's milk protein, chronic diarrhea, and failure to thrive, underwent small intestinal (peroal, suction) biopsy before and after withdrawal of milk proteins. Mucosal specimens were examined by light microscopy and assayed for disaccharidase activities. In all patients, moderate to severe mucosal changes were presented, associated with marked inflammation of lamina propria and damages to the brushborder. Disaccharidase activities (lactase, sucrase, maltase and palatinase) were markedly depressed in all. Follow-up biopsies were obtained in 6 infants, after 3-5 months on a milk-protein-free diet. At the time of the second biopsy, the disaccharidase activities had risen significantly and histologic improvement had occurred in each instance. In infancy, intestinal mucosal lesions due to intolerance to cow's milk protein are histologically indistinguishable from those seen in gluten-sensitive enteropathy and are associated with marked secondary disaccharidase deficiencies. Following therapy, the activity of the disaccharidases become normal or near normal prior to the complete morphologic recovery of the small intestinal mucosa.
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PMID:Disaccharidase deficiency in infants with cow's milk protein intolerance. Response to treatment. 62 28

Significant amounts of sugar were found in 22% of 180 faecal samples from 135 children with acute or chronic diarrhoea. The methods used were the Clinitest method and paper chromatography. There was very good correlation between the results of these methods. Screening by Ph was less reliable. Various di- and monosaccharides were found. However, a disaccharide was never found without the simultaneous finding of its component monosaccharides. In vitro studies showed that the faecal flora has the ability to split disaccharides very rapidly. Within a few minutes much of the disaccharide had been split and no traces could be found after 30 minutes. Since the same process is assumed to take place in the lower gut, children with disacchardase deficency cannot be expected to excrete disaccharide alone in their faeces without the corresponding monosaccharides. The lack of a disaccharide in the faeces does not exclude the possibility of disaccharidase deficiency. Acid hydrolysis of faecal samples in cases of suspected sucrase deficiency seems not to be necessary.
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PMID:Problems in anlysis of faecal sugar. 127 46

The activities of four disaccharidases were examined in resistant (C57Bl/6) and susceptible (C3H/HeN) mice during the primary infection with Giardia muris and after challenge with either trophozoite extract or cysts. Significant decreases in lactase, sucrase, trehalase, and maltase activities in C57Bl/6 mice and lactase and sucrase activities in C3H/HeN mice in the anterior 25% of the small intestine were observed on day 10 after infection. The activities of maltase, sucrase, trehalase, and lactase in the jejunum of C3H/HeN mice were significantly reduced after challenge with trophozoite extract, when compared with the uninfected or infected, but not challenged animals. Decreases in enzyme activities of C3H/HeN mice were evident as early as 12 hours after challenge with the extract. The resistant C57Bl/6 mice showed little change in disaccharidase activity after challenge with trophozoite extract. On the other hand, challenge with cysts resulted in a few decreases in disaccharidase activities in both strains of mice: C57Bl/6 mice showed decreases in the duodenum, while disaccharidases of C3H/HeN mice had lower activity more posteriorly. Thus, challenge with parasite antigen results in a more severe disaccharidase deficiency in susceptible hosts when compared with resistant ones.
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PMID:Disaccharidase activity in the small intestine of susceptible and resistant mice after primary and challenge infections with Giardia muris. 153 93

Investigation of intestinal disaccharide hydrolysis and permeability by means of a non-invasive differential sugar absorption test was performed in a family containing two siblings with primary sucrase-isomaltase deficiency. The procedure, which depends on measurement of urinary excretion ratios after the oral administration of lactose, sucrose, palatinose, lactulose and L-rhamnose, is capable of simultaneous determination of intestinal lactase, sucrase, and isomaltase activity and lactulose:rhamnose permeability. The results corresponded well with those of disaccharidase assay and histological findings in jejunal biopsy tissue obtained from the patients. Palatinose proved a satisfactory substrate for in vivo assessment of intestinal isomaltase activity. The method described provides a reliable and comprehensive assessment of intestinal disaccharide hydrolysis, and simultaneous estimation of permeability assists discrimination of primary from secondary disaccharidase deficiency. The ability to assess three different disaccharidase activities in addition to intestinal permeability by means of a single test, and the simplicity of preservation and transport of urine samples for sugar analysis, makes this a convenient, definitive method for the investigation of defective sugar absorption in both patients and population groups.
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PMID:Combined assessment of intestinal disaccharidases in congenital asucrasia by differential urinary disaccharide excretion. 237 Mar 9

Lactase, sucrase and maltase activities in endoscopic biopsies from the second part of the duodenum were compared to those in Crosby capsule biopsies from the proximal jejunum. In patients with villous atrophy disaccharidase activities were reduced compared with histologically normal mucosa in the duodenum and jejunum. Disaccharidase activities were significantly lower in the duodenum than in the proximal jejunum of patients with histologically normal mucosa and in those with partial villous atrophy but not significantly different for total villous atrophy patients. Primary and secondary disaccharidase deficiencies can be identified in biopsies from the duodenum. Duodenal biopsy is a valid alternative to jejunal biopsy for the diagnosis of disaccharidase deficiency.
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PMID:Small bowel biopsy for disaccharidase levels: evidence that endoscopic forceps biopsy can replace the Crosby capsule. 250 14

Seven patients with congenital sucrase-isomaltase deficiency corresponding to the known diagnostic criteria and five patients having combined disaccharidase deficiencies with unusual pattern characterized by more pronounced sucrase than lactase deficiency were found among 505 children investigated by first jejunal biopsy. On the base of the case histories, the complications and the comparative evaluation of patient and control groups' data (the latter consisted of nine untreated coeliacs) the congenital sucrase-isomaltase deficiency was found to make the patients to be especially susceptible to enteral infections and consequently to postinfectious intestinal damages. These complicated cases do not correspond to the classic diagnostic criteria of the congenital enzyme deficiency causing diagnostic errors. In order to avoid the misdiagnoses the authors suggest modification of the diagnostic criteria of congenital sucrase-isomaltase deficiency as follows: the diagnosis of congenital enzyme deficiency might be verified in spite of mild histological signs and hypolactasia if the degree of lactase deficiency repeatedly and significantly is exceeded by the degree of sucrase deficiency.
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PMID:[Congenital saccharase-isomaltase defect--diagnostic difficulties]. 251 45

We studied lactase, maltase, and sucrase activities in the mucosa of self-filling blind loops (SFBL) in adult rats at weekly intervals after SFBL formation in order to determine the sequence in which disaccharidase activities fall. The studies were carried out on nourished and malnourished rats and extended to a recovery period induced by antibiotics to determine the effects of malnutrition on the establishment and repair of disaccharidase deficiencies caused by bacterial overgrowth. Malnutrition was produced by feeding 50% of the intake of paired rats fed ad libitum. Disaccharidase activities were determined in SFBL from nourished and malnourished rats at 7-day intervals until pandisaccharidase deficiency was established and during a 2-wk recovery period induced by antibiotics. Maximal SFBL bacterial counts in both nourished and malnourished groups of rats and brush-border glycoprotein degradation ratios were established at 7 days. In nourished rats only lactase was deficient at 7 days; maltase and sucrase fell later and sequentially. In malnourished rats all three disaccharidases were reduced at 7 days. Disaccharidase activities in self-emptying blind loops (SEBL), used as operated controls, were not decreased 28 days after surgery. Malnutrition had no effect on disaccharidase activities in the SEBL, and malnutrition did not affect recovery rates with antibiotic therapy. We conclude that small intestinal bacterial overgrowth causes a staggered loss of disaccharidase activities beginning with the loss of lactase activity. In the presence of bacterial overgrowth, malnutrition accelerates the conversion of a mono- to a pan-disaccharidase deficiency.
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PMID:Sequential disaccharidase loss in rat intestinal blind loops: impact of malnutrition. 315 66

Sucrase-isomaltase deficiency is an inherited disaccharidase deficiency that leads to malabsorption of sucrose, with resulting diarrhea and abdominal distention and cramps. We investigated the sucrose-splitting effect of viable yeast cells in eight children with congenital sucrase-isomaltase deficiency, by means of the sucrose hydrogen breath test. This test is based on the fact that hydrogen is released from the malabsorbed sucrose by the colonic microflora. We found that 0.3 g of lyophilized Saccharomyces cerevisiae, given after loading with 2 g of sucrose per kilogram of body weight, reduced hydrogen excretion in all patients, on average by 70 percent, in parallel with a complete loss or evident reduction of clinical symptoms. In vitro, lyophilized and fresh S. cerevisiae (fresh baker's yeast) had appreciable sucrase activity, a low isomaltase and maltase activity, and virtually no lactase activity. The sucrase activity was more inhibited by undiluted than by diluted gastric juice. We conclude that patients with congenital sucrase-isomaltase deficiency who intentionally or unintentionally consume sucrose can ameliorate the malabsorption by subsequently ingesting a small amount of viable yeast cells, preferably on a full stomach.
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PMID:Enzyme-substitution therapy with the yeast Saccharomyces cerevisiae in congenital sucrase-isomaltase deficiency. 355 46

Specific and total activities of the disaccharidases, sucrase, maltase, and lactase are increased in mucosa of the small intestine of the streptozotocin diabetic rat. Because disaccharidases are essential for terminal digestion of carbohydrate, and disaccharidase deficiency is a common clinical problem, understanding the mechanisms regulating disaccharidase activity is important. In normal animals, disaccharidase activities are determined by route of feeding and are decreased by parenteral feeding. The indirect exocrine, endocrine, neurocrine, and paracrine functions of the gastrointestinal tract that are dependent on feeding via the gut are greatly decreased in parenteral as compared with enteral feeding. Hormone secretion by the gut and the pattern of response after feeding may be abnormal in diabetes and might be regulatory for disaccharidases. We tested the hypothesis that the elevated intestinal disaccharidases in diabetes are dependent on enteral feeding. Streptozotocin-injected rats (diabetics) and vehicle-injected rats (controls) were fed rat chow ad libitum for 4 days. A subset of control and diabetic animals was then killed to determine disaccharidase activity of the jejunum at the start of pair-feeding the elemental diet. The remaining animals were fed 60 cal/day of glucose, amino acid (Travasol), and electrolyte solution either intragastrically or intravenously for 4 days. Specific and total activities of disaccharidases were greater in diabetics than in controls under all feeding conditions. In controls, the pattern of activity of disaccharidase specific activity was initial greater than intragastric greater than intravenous. In diabetics, disaccharidase specific activities did not differ among groups. In both controls and diabetics, mean mucosal mass was highest initially; intermediate with intragastric feeding; and lowest with intravenous feeding. In both controls and diabetics, total disaccharidases decreased from initial to intragastric to intravenous. We conclude: (1) disaccharidase specific activity in controls is sensitive to feeding route and nature of diet, but is nearly independent of these factors in diabetics; (2) total disaccharidase activities respond to feeding stimuli in parallel with changes in mucosal mass in both controls and diabetics; and (3) the lack of feeding effect on the elevated specific activities of disaccharidases in diabetes suggests that this elevation is a response to the diabetic state and is independent of enteral factors such as luminal nutrition and gastrointestinal hormones.
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PMID:Elevated intestinal disaccharidase activity in the streptozotocin-diabetic rat is independent of enteral feeding. 640 7


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