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)

Three hundred and twenty Chinese school children aged between 6 and 19 years from six schools in Hong Kong were tested for their lactose digestion status. After an overnight fast, the children were challenged with cow's milk, 5 ml/kg bodyweight (i.e. lactose approximately 0.25 g/kg). Malabsorption was assessed by measuring hydrogen concentration from end-expiratory breath samples taken in duplicate before and at 90 and 180 minutes after the challenge. On average, 10% of the children showed an increase in breath hydrogen excretion within 3 h after the challenge, indicating malabsorption of lactose. None of the children complained of gastro-intestinal symptoms or showed any clinical sign of intolerance to the milk. The number of malabsorbers increased significantly (p less than 0.001) with age, starting at about 3% at the age of 8 and reaching about 27% at the age of 18 years. The sharpest rise occurred between 14 and 15 years. It is concluded that, despite the high prevalence of hypolactasia, Hong Kong Chinese children can consume normal amounts of milk without developing any untoward clinical symptom or sign.
 ...
PMID:Late-onset hypolactasia in Hong Kong school children. 171 30

Prevalences of non-infective bowel diseases are very low in South African urban blacks compared with the white population. In seeking elucidation, using breath hydrogen measurements in series of black and white subjects, small-bowel transit time was determined, and the malabsorption of maize, wheat, and rice investigated. Median transit times in both ethnic groups were similar. Rice was fully, but wheat incompletely absorbed by both groups. Maize, the staple food of blacks, was incompletely absorbed by them, although completely absorbed by the white subjects. Carbohydrate consumption is high in the black population (60-65% of total energy intake). It is probable that in blacks, despite their now eating a low-fibre diet, an expected increase in large-bowel diseases has been inhibited in part by the protective mechanism of fermentation of malabsorbed maize and wheat.
 ...
PMID:Malabsorption of carbohydrate foods by urban blacks. 174 37

To investigate small bowel motility in gastrointestinal amyloidosis, lactulose breath hydrogen tests were performed on 16 patients with histologically proven amyloidosis and 12 age- and sex-matched controls. Fasting breath hydrogen concentration (FBHC) was not significantly different between the two groups, but there was a tendency for FBHC in symptomatic amyloidosis patients (median 31.5, range 3-78 ppm) to be higher than in asymptomatic amyloidosis patients (4, 0-34 ppm, 0.05 less than P less than 0.1) and controls (6, 1-19 ppm, 0.05 less than P less than 0.1). Orocecal transit time (OCTT) was significantly delayed in the amyloidosis group (median 150, range 40-220 min) when compared to the controls (60, 20-110 min, P less than 0.01), but OCTT was not statistically different between symptomatic and asymptomatic amyloidosis patients. These data suggest an impaired motility of the stomach and small intestine in gastrointestinal amyloidosis and the possible role of small intestinal dysfunction such as bacterial overgrowth and malabsorption in the occurrence of symptoms in this disorder.
 ...
PMID:Breath hydrogen test using water-diluted lactulose in patients with gastrointestinal amyloidosis. 174 46

Intrinsic factor is produced by the gastric parietal cell. Its secretion is stimulated via all pathways known to stimulate gastric acid secretion: histamine, gastrin, and acetylcholine. There is, however, a different mode of secretion for both substances: atropine, vagotomy, and H2 receptor antagonists inhibit both intrinsic factor and acid secretion, but secretin and the hydrogen-potassium ATPase antagonist omeprazole have no effect on intrinsic factor while substantially reducing acid secretion. Cobalamin in food is bound to animal protein. Cobalamin deficiency due to inadequate dietary intake is rarely seen in extreme vegetarians (vegans). In the stomach cobalamin is liberated from its protein binding by peptic digestion and bound to R-proteins. Hypochlorhydria or achlorhydria, whether medically induced or not, may impair cobalamin uptake. The cobalamin-R-protein complex is split by pancreatic enzymes in the duodenum, where cobalamin is bound to intrinsic factor. Pancreatic insufficiency may lead to cobalamin deficiency. Lack of intrinsic factor is the commonest cause of cobalamin deficiency; very rarely, aberrant forms of intrinsic factor are produced, but the clinical syndrome is similar. Gram-negative anaerobe bacteria bind the cobalamin-intrinsic factor complex, and bacterial overgrowth of the small intestine diminishes cobalamin resorption. Parasitic infections with fish tape-worm and Giardia lamblia are also associated with cobalamin malabsorption. The cobalamin-intrinsic factor complex binds to the ileal receptors in the terminal ileum. Cobalamin absorption may be impaired after resection or by diseases affecting more than 50 cm of the terminal ileum, such as Crohn's disease, coeliac disease, tuberculosis, lymphoma or radiation. There is clearly a wide diversity in the aetiology of cobalamin deficiency, which requires a versatile diagnostic approach.
 ...
PMID:Intrinsic factor secretion and cobalamin absorption. Physiology and pathophysiology in the gastrointestinal tract. 177 33

Sugar alcohols are incompletely digested in the human small intestine. The residual amounts reaching the colon are digested by colonic bacteria or excreted in stools. Clinical tolerance and energy value of sugar alcohols are related to their respective rates of digestion in the small intestine and the colon. Six healthy volunteers were tested in 5 periods during which they ingested 10 g lactulose, and then, in a random order, an iso-osmotic solution of 20 g isomalt, sorbitol, maltitol, and lactitol. The fraction of sugar alcohols absorbed in the small intestine was evaluated by comparing the amounts of hydrogen excreted in breath for 8 h after the ingestion of lactulose and of sugar alcohols. Energy value of sugar alcohols was determined knowing the amounts absorbed in the small intestine and digested in the colon. Tolerance to the sugar alcohols was good in all volunteers, and not different between sugar alcohols. The mean percentage of malabsorption in the small intestine was significantly higher for lactitol (84 +/- 14 percent, m +/- SEM) than for maltitol and isomalt (44 +/- 7 and 40 +/- 7 percent), its energy value (2.3 +/- 0.3 kcal/g) was significantly lower than the energy value of maltitol (3.1 +/- 0.1 kcal/g, P less than 0.05); whereas those of sorbitol and isomalt were close (2.7 +/- 0.2 and 2.8 +/- 0.1 kcal/g, respectively). In spite of these differences, our results suggest that in our experimental conditions, bacterial digestion of the sugar alcohols reaching the colon was complete, and did not affect their clinical tolerance.
 ...
PMID:[Clinical tolerance, intestinal absorption, and energy value of four sugar alcohols taken on an empty stomach]. 178 48

In two randomized, placebo-controlled, double-blind studies, the efficacy, duration of action and tolerability of a single morning dose of 25, 50, and 100 mg miglitol (BAY m 1099), an absorbable inhibitor of intestinal alpha-glucosidases, were assessed after repetitive sucrose or maize-starch loads (50 g of carbohydrates in 400 ml of water each at 08.00, 12.00, and 17.00 h). With sucrose, miglitol reduced the postprandial rise in blood glucose, serum insulin and serum gastric inhibitory polypeptide concentrations at any dosage. This effect was dose-dependent and confined to the first carbohydrate load in the morning, thus indicating the duration of alpha-glucosidase inhibition of less than 4 h. Sucrose malabsorption, indicated by breath hydrogen responses, occurred dose-dependently with 50 and 100 mg, but not with 25 mg of miglitol. Similarly, symptoms of carbohydrate malabsorption were absent with 25 mg of the inhibitor and mild to moderate after 50 and 100 mg of miglitol. With starch as the substrate, BAY m 1099 led to a significant amelioration of glycemic and hormonal rises after the first meal, but not thereafter. A numerical dose dependency was recognized, but this was not significant at the 5% level. Symptoms of carbohydrate malabsorption were absent with 25 mg and negligible with 50 mg BAY m 1099, but occurred almost regularly with the 100-mg dose. Breath hydrogen concentrations increased gradually with the dose of miglitol administered. A single morning dose of 25-100 mg of miglitol thus may be useful for the control of postprandial hyperglycemia after breakfast. Due to the duration of action of less than 4 h, this substance should be given with the three main meals.
 ...
PMID:Inhibition of glycemic and hormonal responses after repetitive sucrose and starch loads by different doses of the alpha-glucosidase inhibitor miglitol (BAY m 1099) in man. 178 28

The absorbable deoxynojirimycin derivative emiglitate (BAY o 1248) is a potent competitive inhibitor of small intestinal alpha-glucosidases in man. In two similar randomized, placebo-controlled, double blind investigations, the efficacy, duration of action and tolerability of single doses of 10, 20 and 40 mg emiglitate have been assessed in healthy male volunteers after repeated sucrose or maize-starch loads at 08.00, 12.00 and 17.00 h. Even at the lowest dose used, emiglitate almost abolished the glycaemic (-88%) and hormonal responses after the first sucrose meal, simultaneously evoking significant hydrogen evolution (mean peak H2-concentration greater than 100 ppm), which was not related to the dose, and which induced unacceptable symptoms of carbohydrate malabsorption, i.e. at the dosages tested, the inhibition of glycaemic and hormonal responses was at the expense of intolerable gastrointestinal adverse effects. Flattening of postprandial responses of blood glucose, serum insulin and gastric inhibitory polypeptide was still apparent after a second sucrose load 4 h later, demonstrating long-lasting inhibition of alpha-glucosidase activity. After starch, the dose dependency of inhibition emerged more clearly than after sucrose, i.e. the reduction was less pronounced. However, emiglitate led to significant reduction of the glycaemic and hormonal rises after both the first and second starch meals. Symptoms of carbohydrate malabsorption were absent after 10 mg and were negligible with 20 mg or 40 mg emiglitate. Breath hydrogen concentration increased gradually, indicating slight but significant carbohydrate malabsorption after the highest dose of the alpha-glucosidase inhibitor. The results show that a single morning dose of 20-40 mg emiglitate might be useful in the control of postprandial hyperglycaemia after breakfast and lunch.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Inhibition of sucrose- and starch-induced glycaemic and hormonal responses by the alpha-glucosidase inhibitor emiglitate (BAY o 1248) in healthy volunteers. 181 67

With the objective of determining the relationship between ascariasis and carbohydrate absorption from rice, breath hydrogen tests (BHT's) were performed in two study populations of Burmese village children. Using a rice test meal, breath hydrogen peaks greater than 10 ppm above baseline within 4 hours (indicating rice malabsorption) were seen in 24 out of 55 (44 per cent) Ascaris lumbricoides infected children and 3 out of 18 (17 per cent) non-infected children (age 18-59 months). In another ascaris endemic village 139 children (age 36-108 months) underwent a rice meal BHT. Seventy children had been regularly dewormed for 2 years (single dose levamisole 50 mg every 3 months) whilst 69 children had been dewormed once in 2 years, 6 weeks before breath testing. Regularly dewormed children showed a lower prevalence of rice malabsorption (33 per cent) compared to the control group (54 per cent) (P < 0.05). These findings suggest that malabsorption of carbohydrate from rice can occur during Ascaris lumbricoides infection in children.
 ...
PMID:Absorption of carbohydrate from rice in Ascaris lumbricoides infected Burmese village children. 184 93

In order to collect data on (1) the prevalence of lactose malabsorption and (2) the value of indirect diagnostic methods for hypolactasia in diabetics, we compared lactose tolerance tests using serum glucose, serum galactose (after oral ethanol intake) and breath hydrogen excretion as diagnostic cutoff in 144 nondiabetic and 46 diabetic subjects. A good rate of concordance was found for the hydrogen breath test and galactose-dependent lactose tolerance test. The glucose-dependent lactose tolerance test was found to be of satisfactory diagnostic value in nondiabetic subjects and was useless for diagnostic purposes in diabetics. Lactose malabsorption was no more frequent in diabetics than in controls and lactose intolerance was found to be less frequent in the diabetic group. A distinction between hypolactasia and other gastrointestinal disorders in diabetics is possible by ambulatory indirect tests.
 ...
PMID:Concordance of indirect methods for the detection of lactose malabsorption in diabetic and nondiabetic subjects. 186 74

A group of 24 patients which underwent extensive abdominal surgery (gastrectomy and esophagus resection) were fed with a chemically defined diet by way of a needle catheter jejunostomy starting on day five postoperatively. On the fourth postoperative day the jejunocaecal transit time was measured by hydrogen breath test with a median of 97.5 min. Under enteral nutrition, hydrogen exhalation showed a significant rise in all patients. The 8 patients who developed diarrhea (33%) had significantly elevated hydrogen exhalation in relationship to the patients with no diarrhea. 6-12 h before diarrhea, patients had a significant increase in their hydrogen exhalation in correlation to the beginning of carbohydrate malabsorption. Therefore, the hydrogen breath test is a simple, non-invasive method to evaluate carbohydrate malabsorption and the risk of developing diarrhea under enteral nutrition.
 ...
PMID:[Monitoring of postoperative enteral feeding using the H2 breath test]. 190 28


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