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

A better understanding of the physiologic response to and nutritional consequences of acute diarrhea can facilitate an improved outcome for this and other infectious diseases. Acute diarrhea causes the host to undergo a sequence of hormonal, metabolic, and immunologic responses, all of which have nutritional consequences. Its most profound effect is on the malabsorption of water and electrolytes by the intestinal epithelial cell, the electrolyte, leading to dehydration. Diarrhea is defined as any alteration of fluid and electrolyte movement that results in increased fecal water due to an excessive amount of solute in the stool. Infectious agents that damage the enteric mucosa cause villous atrophy, which is accompanied by increased proliferation, migration, and extrusion of epithelial cells; this results in alterations of fluid and electrolyte movement and is the final common pathway to the development of diarrhea. During the acute stages of diarrhea, there are increased losses of fecal weight and volume as well as sodium and chloride and the level of disaccharidase enzymes is depressed. Different bacteria affect different parts of the gastrointestinal tract. After bacterial adherence and surface colonization of the intestinal epithelium, diarrhea can result from any of 3 major mechanisms: 1) production and release of enterotoxins, 2) direct invasion of the mucosa or submucosa, and 3) adhesion and cytotoxic disruption of the microvilli of the enterocyte. There is evidence of diarrhea-associated changes in the plasma concentration of certain gastrointestinal hormones and indications that calcium plays a key role in the intracellular regulation of electrolyte transport. The impact of diarrhea will be more significant in the debilitated or marginally nourished child. To improve the host response to infection, nutrients that are essential for optimal immune function and are rapidly being metabolized should be selectively replaced, while nutrients needed by the offending organism can be withheld.
 ...
PMID:Nutritional implications and physiologic response to pediatric diarrhea. 394 85

Cholesterol and bile acid metabolism and vitamin B12 were studied in 19 patients with heterozygous familial hypercholesterolemia in an 8-yr follow-up (3-12 yr after ileal bypass operation), and in 11 unoperated controls. Absorption of cholesterol and vitamin B12 were decreased by the operation, but improved slowly, and at 8 yr cholesterol absorption was normal. Cholesterol excretion as fecal neutral steroids was not increased by the operation, and at 8 yr the flux of endogenous cholesterol to the gut was similar in the operated and control patients. Cholesterol absorption was positively correlated with mouth to anus transit time in the unoperated patients. Fecal bile acid excretion was increased immediately after the operation and continued to increase even after the second postoperative year. In the operated patients fecal excretion of fat, water, and dry matter were positively correlated with fecal bile acid excretion. Our study suggests that adaptive changes occur slowly after ileal bypass, resulting in gradual normalization of cholesterol absorption, despite continuing bile acid malabsorption, and that the intestinal transit time is related to steroid absorption even under physiologic conditions.
 ...
PMID:Adaptation of cholesterol and bile acid metabolism and vitamin B12 absorption in the long-term follow-up after partial ileal bypass. 394 24

Glucose polymer derived from corn starch is widely used in infant formula and nutritional supplements as a readily digestible, low osmolarity source of calories. We have previously observed that glucose polymer causes a marked increase in intestinal calcium absorption in patients with intestinal malabsorption and in normal subjects. The present study investigates the effect of concurrently administered glucose polymer on intestinal 45calcium absorption in rats. The effect of glucose polymer on calcium absorption was compared to that of equivalent doses of dextrose or lactose. Femur radioactivity was determined as an index of calcium absorption. Carbohydrates were prepared at doses of 0.5, 2.0 and 4.0 mg/g body weight and administered with 45Ca by stomach gavage. Control rats received 45Ca in water alone. Coadministration of glucose polymer resulted in a dose-dependent increase in calcium absorption. At the highest dose of polymer studied calcium absorption was 75% greater than in control animals. Administration of lactose and dextrose also resulted in a dose-dependent increase in calcium absorption. Calcium absorption was 122 and 67% greater than controls when 4 mg/g BW lactose and dextrose were given with the 45Ca. We conclude that glucose polymer stimulates calcium absorption in rats similar to lactose and glucose. These results suggest that glucose polymer may be a useful therapeutic adjunct in patient groups in which there is a desire to increase intestinal calcium absorption.
 ...
PMID:Enhancement of calcium absorption in rats by coadministration of glucose polymer. 396 33

Patients with cystic fibrosis have an increased proportion of glycine conjugated bile acids with diminished tauroconjugates which could contribute to fat malabsorption. Twenty-two CF children with documented steatorrhea were supplemented with taurine capsules (30 mg/kg/day) and placebo during separate 6-month treatment periods. Alteration of the glycine/taurine conjugation pattern was verified in two patients who showed a predominance of tauroconjugates as a result of taurine supplementation. On taurine, steatorrhea was reduced (p less than 0.05) by 17.6 +/- 9.7% in 19 patients who completed the study as was the excretion of long-chain saturated fatty acids. There was no change in linoleic acid (C 18:2) excretion. In the 10 patients with a more severe degree of steatorrhea the decrease in fat loss approached 20% and a close relationship was found (r = 0.84, p less than 0.01) between the extent of the fatty acid loss on placebo and the decrease of this loss on taurine. A linear relationship was found between the percentage decrease of individual fatty acids and their log solubility in water. No change was found in the daily excretion of bile acids, neutral sterols, and nitrogen. Fasting plasma fatty acids, cholesterol, and triglycerides were also unchanged. Monitoring of growth over the two 6-month periods revealed a marginal (p less than 0.1) increase of weight velocity expressed as a percentage expected for age (83.4 +/- 11.3----117.1 +/- 16.5). The increase in height velocity in response to taurine showed a more modest trend (95.3 +/- 7.8----110.7 +/- 10.6).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Effect of taurine supplements on fat absorption in cystic fibrosis. 401 38

Acute truncal vagotomy causes increased net secretion of water, sodium and potassium from the proximal portion of the jejunum. This is presumed to occur because of the sudden loss of vagal cholinergic tone. Glucose absorption from the proximal part of the jejunum was not affected by acute vagotomy despite the large changes in net water and electrolyte fluxes. Adaptation after vagotomy and pyloroplasty was associated with a significant increase in jejunal absorptive capacity for glucose, water, sodium and potassium. These findings contribute another dimension to the understanding of the rapid rises in postprandial blood sugar observed in patients after vagotomy to help explain the abnormal glucose tolerance in the presence of glucose malabsorption. The increased jejunal absorptive capacity observed in the chronic vagotomy group is believed to occur in compensation for malabsorption resulting from rapid intestinal transit.
 ...
PMID:Acute and chronic effects of truncal vagotomy upon glucose absorption, water and electrolyte fluxes in the small intestine of the rabbit. 401 42

Using a double-lumen tube perfusion system, solutions of glucose (1.0, 2.5, and 5.0 g 100ml(-1)) have been perfused into the upper jejunum of 22 Zambian African subjects in order to study their glucose absorption kinetics. None of them had clinical evidence of malnutrition or intestinal disease. In 10 there was no evidence of an infective disease (;normal' group); seven had tuberculosis; five had acute bacterial infections. The mean serum albumin concentration was significantly lower in those with infections; the mean total and gamma-globulin concentrations were significantly higher in the tuberculosis group. There was good reproducibility in triplicate assessments of glucose and water absorption rates in the individual subjects. Despite a wide scatter, the mean glucose kinetic curves were significantly flatter in those with infections than in the normal group (p<0.02). There was a significant association between glucose and water absorption rates in the individuals. D-xylose absorption was estimated in 11 subjects and there was a significant correlation between that and the glucose absorption rate. Jejunal morphology (n=9) and disaccharidase concentrations (n=6) were normal for African subjects and there were no significant associations between either of those and the absorption rates. Galactose absorption kinetics have been studied in an additional four relatively normal Zambian Africans. This study suggests that systemic bacterial infections can produce malabsorption. This may be relevant to the weight loss in patients with pulmonary tuberculosis and also to the aetiology of kwashiorkor.
 ...
PMID:Glucose absorption kinetics in Zambian African patients with and without systemic bacterial infections. 411 99

Approximately 20 inherited disorders of kidney transport occurring in man have so far been defined. Most of these diseases have characteristic clinical profiles. They can be divided into four groups: 1) the amino acid transport mutations which include the cystinurias, hyperdibasicaminoaciduria, Joseph syndrome, Hartnup disease, and the methionine malabsorption syndrome: 2) the sugar transport mutations characterized by glucose (renal glucosuria), and glucose-galactose malabsorption; 3) the electrolyte and water transport disorders, among which are familial hypophosphatemic rickets, vitamin D-dependent rickets, pseudohypoparathyroidism, proximal and distal renal tubular acidosis, and nephrogenic diabetes insipidus; and 4) the "mixed" kidney transport mutations such as the "Busby", Fanconi, Lowe, Luder-Sheldon syndromes, and glucoglycinuria.
 ...
PMID:Clinical phenotypes in kidney transport disorders. 437 65

A double-lumen perfusion technique has been used to study amino acid and peptide absorption in eight normal control subjects, 13 patients with untreated adult coeliac disease, and 16 patients with dermatitis herpetiformis who had varying morphological abnormalities of the small bowel. All subjects were perfused with isotonic solutions containing 10 mM glycyl-L-alanine and 10 mM glycine + 10 mM L-alanine. Patients with adult coeliac disease had impaired absorption of glycine (p < 0.01) and L-alanine (p < 0.05) from the amino acid solution compared with the control subjects. Amino acid uptake from the dipeptide solution was not significantly impaired, although four individual patients had impaired uptake of both amino acids. In contrast to these findings, very few patients with dermatitis herpetiformis had impaired amino acid absorption from either solution. Sodium absorption was impaired from both solutions when the groups of patients with adult coeliac disease and dermatitis herpetiformis with subtotal villous atrophy and partial villous atrophy were studied, and there were patients in each group who secreted sodium and water. The results suggest that malabsorption of dietary protein is unlikely to occur in dermatitis herpetiformis but may occur and contribute to protein deficiency seen in some severe cases of adult coeliac disease. The impairment of sodium and water absorption provides evidence that there may be functional impairment of the jejunal mucosa in dermatitis herpetiformis as well as in adult coeliac disease.
 ...
PMID:Amino acid and peptide absorption in patients with coeliac disease and dermatitis herpetiformis. 482 Jun 29

The role of decreased absorption of electrolytes and water by the jejunum in the pathogenesis of diarrhoea was examined in patients with intestinal scleroderma, ileocolitis, gastric hypersecretion, or extensive ileal resection. Absorption of electrolytes and water from a 20-cm segment of jejunum was compared in 10 patients and six healthy volunteers. Malabsorption of electrolytes and water by the jejunum may contribute to diarrhoea in scleroderma, regional enteritis, and gastric hypersecretion. After ileal resection, jejunal absorption was normal.
 ...
PMID:Jejunal transport of electrolytes and water in intestinal diseases. 537 98

An epidemic of acute diarrhea in a village in southern India in 1972 was associated with a high rate of isolation of enteric pathogenic bacteria from the patients and lasted for three months. There was no significant association between the prevalence of enteroviruses or parasites and cases of diarrhea. The epidemic started as a common-source outbreak due to the contamination of well water, and there were many secondary cases probably due to a person-to-person spread. The illness did not produce chronic diarrhea or malabsorption.
 ...
PMID:A common-source epidemic of mixed bacterial diarrhea with secondary transmission. 609 2


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>