Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Individuals with chronic renal failure (CRF) may have a variety of gastrointestinal (GI) problems, including dyspepsia, acid peptic disease, and bacterial overgrowth. We investigated gastrointestinal function in 11 uremic patients, seven of whom were on dialysis three times a week and four who were not on dialysis. Ten normal subjects were studied as controls. The nutritional status of the patients did not differ from that of the control subjects. Seven patients demonstrated abnormal GI endoscopic findings, although none was severe; they also had prolonged oral-cecal transit times but had no evidence of bacterial overgrowth, and all had normal numbers of lymphocyte subpopulations within the intestinal mucosa. The patients had significantly reduced activities of mucosal sucrase and maltase but not of lactase. In spite of the reductions in these enzymatic activities, carbohydrate malabsorption was not evident in the CRF group, probably because of the vast reserve of the small intestine. No differences were noted between the groups in the activities of several intestinal peptidases. From these data, we concluded that GI function is essentially normal in patients with CRF and postulate that this normality, which is in contrast to previous findings, is related to recent advances in the clinical management of uremic patients.
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PMID:Gastrointestinal function, morphology, and immune status in uremia. 213 74

This double-blind study was performed to evaluate the relation of the glycemic and hormonal (insulin, gastric inhibitory polypeptide) responses to standardized starch and sucrose meals to signs (H2 exhalation) and subjective symptoms of carbohydrate malabsorption during administration of 100 mg BAYm 1099 (miglitol) t.i.d. over a period of 8 weeks. Two groups of 8 male healthy volunteers received either placebo or verum. Oral sucrose loading tests (50 g) with and without miglitol were performed at day -5, 1, 25 and 53 of the study, starch loading tests (50 g) with and without the inhibitor were carried out at day -2, 4, 28 and 56. Miglitol significantly flattened the glycemic responses to sucrose and starch without evidence of diminished efficacy over the 8-week period. Also the blunting effect of miglitol on serum insulin and gastric inhibitory polypeptide responses and the stimulation of breath hydrogen exhalation proving carbohydrate malabsorption with starch and sucrose remained unchanged over time. Comparing breath hydrogen exhalation, responses were more pronounced after sucrose than after the starch loading tests. Symptoms (bloating, flatulence, diarrhea, cramps) were merely noticeable with starch as the substrate, but clearly present after sucrose. These symptoms were substantially curtailed during continuous drug intake. It is concluded that - irrespective of the substrate (starch/sucrose) - there is no escape of the desired effects of alpha-glucosidase inhibition by miglitol over 8 weeks, but symptoms of gaseousness due to carbohydrate malabsorption may undergo habituation.
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PMID:Postprandial glycemic control, hormonal effects and carbohydrate malabsorption during long-term administration of the alpha-glucosidase inhibitor miglitol. 229 49

110 children suffering from malabsorption underwent several biopsies of the gut to confirm coeliac disease (CD) following the ESPGAN criteria. We studied the values for alkaline phosphatase (AP) in the intestinal mucosa after gluten challenge. In 42 patients the after challenge biopsy was normal, thus excluding coeliac disease. In 68 children the mucosa was severely damaged confirming CD. In all biopsy specimens lactase, invertase, maltase and alkaline phosphatase were measured. We found a good correlation between PA values and severity of mucosal damage, showing that measurement of PA in the mucosa is helpful in assessing the degree of mucosal atrophy in children suffering from malabsorption.
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PMID:[Alkaline phosphatase in the intestinal mucosa of children with the malabsorption syndrome]. 250 30

Atrophy of the small intestinal mucosa is functionally characterized by a reduction in non-electrolyte transport in vivo. In order to elucidate the cellular defect being responsible for this malabsorption, we have studied the Na+-dependent D-glucose accumulation as well as the activities of aminopeptidase M and maltase in brush border membrane vesicles prepared from jejunal self-emptying blind loops and corresponding intestinal segments of sham-operated control rats. Membrane vesicles from atrophic mucosa did not show any differences in D-glucose uptake or in enzyme activities when compared with those derived from normal intestine. Thus it is unlikely that the impaired non-electrolyte absorption in the atrophic mucosa in vivo is due to a defect in cellular transport processes. It is more probable that the functional impairment is the result of the diminished absorptive surface in this pathophysiological condition.
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PMID:[Functional characterization of luminal enterocyte membranes of the small intestine mucosa using isolated brush border membranes]. 288 Apr 30

The tests with lactose loading followed by the assay of blood sugar were conducted in 500 normal subjects, aged from 18 to 89 years, and 262 patients with gastro-intestinal diseases, aged from 25 to 55 years. When lactose malabsorption was detected, aspiration biopsy of the small intestine mucosa was performed followed by the study of the structure and the level of a number of disaccharidases (lactase, maltase, saccharase). Lactose malabsorption was detected in 72 (14.4%) out of 500 normal subjects (10.6%--aged 18-59, and 20%--aged 60-89 years), among them there were 12.5% of Russians, 13% of Byelorussians and 5.8% of Ukrainians (aged 25-55 years). The secondary lactose malabsorption was recorded in 44% of patients with ulcerative colitis, in 33% of patients with chronic enterocolitis, in 11.5% of patients with gastric ulcer, in 8% of those with duodenal ulcer, in 23.5% of patients with chronic gastritis attended by lowered secretory function, and in 8% of those with enhanced secretory function.
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PMID:[Current problems of lactase deficiency]. 296 77

Acarbose delays the production of monosaccharides (notably glucose) by inhibiting the alpha-glucosidases associated with the brush-border membrane of the small intestine which are responsible for the digestion of complex polysaccharides and sucrose. In healthy subjects acarbose 100 to 200 mg significantly inhibits postprandial glucose, insulin and triglyceride responses, with some evidence of carbohydrate malabsorption with the higher dose. Clinical trials in patients with non-insulin-dependent diabetes mellitus showed that acarbose improved diabetic control, especially postprandial blood glucose levels, independent of whether the patients were receiving concomitant oral antidiabetic drugs in addition to dietary management. In comparative studies acarbose was significantly superior to placebo, and comparable to biguanides, when used alone or as an adjuvant to sulphonylurea therapy. Trials in patients requiring insulin to control their diabetes demonstrated that acarbose significantly reduced postprandial blood glucose concentrations, resulting in a smoother diurnal blood glucose-time curve and improved symptoms associated with nocturnal hypoglycaemia. Daily insulin requirements were sometimes reduced. In large multicentre trials acarbose up to 600 mg/day for 3 to 12 months improved glycaemic control in approximately 55% of patients with non-insulin-dependent or insulin-dependent diabetes mellitus. Apart from its use in diabetes, encouraging preliminary results have been obtained with acarbose in other therapeutic areas such as dumping syndrome, reactive hypoglycaemia, and types IIb and IV hyperlipoproteinaemias--however, further clinical experience is needed in these settings before clear conclusions can be drawn. No serious side effects have been reported during treatment with acarbose, although it is associated with a high incidence of troublesome gastrointestinal symptoms such as flatulence, abdominal distension, borborygmus and diarrhoea. The incidence of these reactions usually decreases with time. Thus, acarbose represents the first of a new class of oral antidiabetic drugs--the alpha-glucosidase inhibitors. It has proven useful for improving glycaemic control when used as an adjunct to standard therapy involving dietary restriction, oral antidiabetic drugs and/or subcutaneous insulin. That being the case, acarbose should provide the clinician with an interesting treatment option which can be used in a broad range of patients with diabetes mellitus in whom 'traditional' management approaches produce suboptimal glycaemic control.
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PMID:Acarbose. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential. 328 12

NMRI mice immunosuppressed with dexamethasone followed by challenge intraesophageally with axenic Giardia lamblia (Portland I) trophozoites had severe infection in terms of the trophozoite counts in the jejunum. Although the immunosuppressive treatment with cortisone itself resulted in a deleterious effect on brush border membrane enzymes, the decline in disaccharidases (sucrase, maltase, and lactase) and alkaline phosphatase was highly significant (P less than 0.001) following G. lamblia infection. The alterations in enzymatic activity in immune intact but infected animals demonstrated the potential of the parasite itself to cause damage to the brush border membrane. We believe that individuals with underlying immunodeficiency, upon infection with G. lamblia, may have increased damage of the brush border membrane, leading to severe malabsorption.
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PMID:Giardia lamblia infection in immunosuppressed animals causes severe alterations to brush border membrane enzymes. 276 19

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

Jejunal biopsies from six patients having the small bowel enteropathy associated with common variable immunodeficiency have been subjected to analytical subcellular fractionation and enzymic and regulatory peptide microassay to define the organelle pathology of this syndrome. Compared with normal subjects, the immunodeficient patients had decreased activities of the three brush border enzymes: alkaline phosphatase, gamma-glutamyl transferase and alpha-glucosidase. The other organelle marker enzyme activities and all the regulatory peptide concentrations did not differ from the controls. Density gradient experiments showed a complete loss of particulate beta-glucosidase (lactase) with activity entirely located in the cytosol. The integrity of other organelles was normal. These data indicate that the enteropathy of common variable immunodeficiency is associated with abnormalities in the jejunal brush border analogous to those present in tropical malabsorption syndrome.
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PMID:Jejunal mucosal enzyme activities, regulatory peptides and organelle pathology of the enteropathy of common variable immunodeficiency. 369 46

A major barrier to the widespread clinical use of an alpha-glucosidase inhibitor such as Acarbose, is the unpleasant gastrointestinal symptoms of carbohydrate malabsorption associated with its use. Acarbose is usually administered as a tablet and eaten with the first mouthful of the meal, making its uniform distribution through the meal unlikely. In the present study, Acarbose was crushed to a powder and mixed through a test meal before it was consumed. Six healthy young men consumed test meals containing 75 g carbohydrate either as whole brown rice or as ground brown rice. When Acarbose was uniformly mixed through a ground rice meal prior to digestion it produced dose-dependent reductions in the postprandial glucose, insulin and GIP responses which were evident at doses as low as 12.5 mg. The responses to whole brown rice were intermediate between those to 12.5 and 25 mg Acarbose in ground brown rice. In tablet form Acarbose was only one quarter as effective in flattening the post prandial glucose and insulin responses as it was in powder form. These results highlight the importance of uniform distribution of Acarbose through a carbohydrate meal in order to achieve maximum effectiveness in delaying digestion and absorption and yet not promoting carbohydrate malabsorption.
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PMID:Optimum effectiveness of intestinal alpha-glucosidase inhibitors: importance of uniform distribution through a meal. 388 43


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