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)

The effect of a new complex oligosaccharide (Bay g 5421) of microbial origin on human intestinal alpha-glucosidehydrolase activity was tested in mucosal homogenate from human small bowel biopsy specimens. The alpha-glucosidehydrolase inhibitor (alpha-GHI) exerted a potent inhibitory effect on glucoamylase, sucrase, and maltase, was minimally effective on isomaltase, and did not affect trehalase and lactase activity. Kinetic analysis revealed a fully competitive type of inhibition with a Ki of 1.3 x 10(-6) M; thus the inhibitor had a 15,000-fold higher affinity to the enzyme sucrase than its natural substrate sucrose. The new compound may prove to be useful in the study of carbohydrate maldigestion and malabsorption and may possibly be of therapeutic benefit in diabetes and obesity.
 ...
PMID:Inhibition of human intestinal alpha-glucosidehydrolases by a new complex oligosaccharide. 44 22

The breath hydrogen test (BHT) was adapted for use in young infants and children. The diagnostic criterion of sugar malabsorption in the BHT was determined by oral administration of 0.5 g/kg of unabsorbable sugar (lactulose) to 21 healthy infants and children. A maximum increase in breath hydrogen less than 0.05 ml/min per m2 was observed in all subjects. A good correlation between results by the BHT and by the ordinary lactose tolerance test was obtained after oral administration of 2 g/kg lactose to 21 healthy infants and children, 2 congenital lactase-deficient infants, and 7 adults. Using this test, 80 healthy Japanese infants and children (aged between one month and 15 years) and 18 adults were examined for lactose malabsorption after a dose of 1 g/kg lactose. All infants and children under 2-years old absorbed lactose completely. The incidence of lactose malabsorption was 30% in 3-year, 36% in 4-year, 58% in 5-year, and 86% in 6-year-old children, 85% in schoolchildren, and 89% in adults. Thus the incidence of lactase deficiency gradually increases with age from 3 years, and about 90% of all normal Japanese adults are lactase-deficient.
 ...
PMID:Breath hydrogen test for detecting lactose malabsorption in infants and children. Prevalence of lactose malabsorption in Japanese children and adults. 47 26

A 10-year-old boy with severe familial lactose intolerance in infancy (vomiting, failure to thrive, lactosuria (5.25 g/l), sucrosuria (12 g/l), and aminoaciduria. Intestinal disaccharidases (including lactase and sucrase) normal at age 6 and 20 weeks. Oral lactose tolerance test at this age resulted in lactosuria (4.6 g/l); sucrose tolerance test, in sucrosuria (18.5 g/l). In contrast, intraduodenal lactose tolerance test gave only low lactose excretion in urine (0.28 g/l). He improved rapidly and had no lactosuria on intraduodenal feeding with citric acid milk. The lactosuria diminished as age increased, but was still higher at age 6 years than that of controls. He tolerated normal disaccharide containing food after 1.5 years of age. At 5.5 to 6 years, he had symptoms of lactose malabsorption, and an isolated lactase deficiency was proved. At 10 years, he still tolerates only limited amounts of milk. The defect in severe familial infantile lactose intolerance seems to be localized in the gastric mucosa. Acquired lactase deficiency can appear later in childhood in this syndrome.
 ...
PMID:A boy with severe infantile gastrogen lactose intolerance and acquired lactase deficiency. 52 43

Adults eating a Western diet digest and absorb ingested food containing approximately 100 g fat, 350 g carbohydrate, and 75 g protein daily. Normal fat absorption requires adequate gastric, pancreatic, liver-biliary, mucosal, and lymphatic function. Carbohydrate and protein absorption is much less dependent on liver-biliary and lymphatic function. The intestine has a large reserve capacity for digestion and absorption of nutrients which is due to both excess function and to adaptive changes which increase function in one segment of the digestive-absorptive system when it is decreased or lost in another segment. The large reserve capacity explains why most of the prevalent intestinal diseases seldom cause clinically detectable changes in absorption. However, there are more than 30 less-common human diseases which cause malabsorption of one or more nutrients. Those that cause the malabsorption syndrome, i.e., steatorrhea and weight loss, can be conveniently categorized according to the major deficiency leading to the absorptive defect as follows: insufficient pancreatic enzyme activity, insufficient bile acid, disease of the small intestinal wall, multiple defects, mechanism unknown, and drug-induced malabsorption. A few diseases, most of which are congenital, cause malabsorption of only one or a few related nutrients such as lactose malabsorption in lactase deficiency. Most of the tests currently in use for detecting and diagnosing the cause of malabsorption are relatively insensitive and nonspecific. Chemical analysis of the fat in a three-day stool collection remains the single best test for diagnosing the malabsorption syndrome. However, a breath test using Triolein labeled with either the radioactive or stable isotope of carbon may be an important recent advance. Other breath tests are also currently being investigated for quantitating absorption or malabsorption of various substances including bile acids and various sugars. Studies of the function of the intestinal epithelial cells are usually best accomplished using tissue obtained by per oral biopsy. Biopsy specimens are used for many types of study including light and electron microscopic examination, chemical and enzymatic assays, tissue culture, and uptake of various radiolabeled compounds.
 ...
PMID:Normal and abnormal intestinal absorption by humans. 54 Jun 10

Selective adult type lactose malabsorption appears in childhood or adolescence because of the great decline in jejunal lactase activity. There is strong evidence that this is a genetically determined disorder. Specifically, selective adult type lactose malabsorptions seem to be inherited by a single autosomal recessive gene. In the present prospective study the transition from the state of lactose absorption to that of lactose malabsorption was documented for the first time in two Finnish boys who were at risk for selective adult type lactose malabsorption because the parents of both boys had the disorder. At the age of 14 and 9 years, respectively, the boys had normal lactose absorption. Three years and 7 months and 4 years and 5 months later, respectively, the boys were shown to have lactose malabsorption. The period of documented transition averaged less than 4 years. These manifestations clearly strengthen the genetic model proposed.
 ...
PMID:More evidence for the recessive inheritance of selective adult type lactose malabsorption. 57 85

The influence of malabsorption of lactose, as a result of primary lactase deficiency, on the absorption of the nutrients in milk was tested in four healthy controls and four subjects with lactase deficiency. An ileal perfusion technique was used to quantify arrival in the ileum of nutrients and a nonabsorbable marker (polyethylene glycol, PEG 4000) ingested as a test meal of milk. The meal was 250 ml of whole milk or milk in which the lactose had been hydrolyzed to glucose and galactose. In the fasting state, ileal flow of volume, protein, carbohydrate, and electrolytes was small and not different in controls and lactase-deficient subjects. Ileal flow increased in all subjects after the test meal of milk; more fluid and nutrient was recovered from the ileum in lactase-deficient subjects after whole milk than in control subjects or in lactase deficiency after hydrolyzed milk. Two deficient subjects showed marked malabsorption of lactose (35 and 50%); two did not. Protein, calcium, magnesium, and phosphorus were also recovered from the ileum in greater quantities in lactase deficients after whole milk. However, apart from decreased absorption of lactose, the nutritional consequences of malabsorption in association with primary lactase deficiency in adults are probably minimal.
 ...
PMID:Absorption of nutrients in lactase deficiency. 58 2

Giardia lamblia has a cosmopolitan distribution. The organism exists in two stages--the trophozoite and the cystic stage. Infected children may have acute or chronic diarrhea, crampy abdominal pain, anorexia, malasorption and poor weight gain and may be misdiagnosed as celiac disease. Infection may be selflimited or chronic even over years. Diagnosis is usually made by finding the characteristic cyst in stool specimens or by duodenal aspiration. Histological sections and impression smears (AMENT) of intestinal mucosa biopsies have been proved to be the most reliable method for detecting giardiasis. Evaluation of impression smears for parasites is easier and quicker than examining serial sections of biopsies. Out of 175 selected patients with intestinal complaints which were undergone small intestinal biopsy 11 were infected with giardia lamblia (6.2%). All infected children were symptomatic, malabsorption could be demonstrated in 5/8, lactase levels were reduced in most children. Examination of duodenal aspirates, stool specimens and histological sections (routine histology) alone would not have been diagnostic in every case. Evaluation of impression smears proved to be a reliable method in detecting giardia lamblia infection and is recommended whenever an intestinal biopsy is performed.
 ...
PMID:[The value of the "impression smear" in detecting giardia lamblia infection (author's transl)]. 64 94

The introduction of a simple method for analysis of 14CO2 in breath allowed a more widely application of breath-tests in the diagnosis of gastroenterological diseases. During a breath-test a 14C-labelled compound is administered orally and 14CO2 is subsequently measured in breath by discontinuous samplings of 14CO2 by virtue of a trapping solution (hyamine hydroxide). Most helpful tests in gastroenterology are the 14C-glycyl-cholate breath test for detecting increased deconjugation of bile acids due to small intestinal bacterial overgrowth or bile acid malabsorption in ileal resection or Crohn's disease of the ileum, the 14C-lactose breath test in lactase deficiency, whereas the 14C-tripalmitin test seems less helpful in the diagnosis of fat malabsorption. A 14C-aminopyrine breath test may turn out to be a simple and valuable liver function test. Oral loading tests with breath analysis of H2 have shown to be helpful in the diagnosis of carbohydrate malabsorption, determination of intestinal transit time and intestinal gas production. Due to technical reasons (gas-chromatographie analysis) H2-breath analysis is still limited to research centers. Despite low radiation doses after oral administration of 14C-labelled compounds oral loading tests with H2- or 13C-analysis might be preferable in the future.
 ...
PMID:[Breath-analysis tests in gastroenetrological diagnosis]. 77 14

Examinations of faeces (pH, Clinitest and Clinistix) are liable to contribute to the diagnosis of lactose malabsorption. To confirm the diagnosis the test is to be repeated while Lactase 500 is added to the child's milk. The enzyme does not split the lactase into the two monosaccharides, thus eliminating the malabsorption. The new drug Lactase 500 was used as a diagnostic parameter and for the treatment of lactose malabsorption in 20 infants. The effect on both groups was confirmed as mentioned by foreign authors. In addition to a very simple diagnostic method, which can be performed in the practitioner's office, there are two methods of treating lactose malabsorption: 1. feeding milk free of lactose, 2. feeding milk with an addition of Lactase 500. As in an earlier publication we assumed that about 10 per cent of the population suffers from secondary malabsorption of lactose, it seems advisable to check with the help of the described to simple methods all children with chronic diarrhoea.
 ...
PMID:[Diagnosis and therapy of lactose malabsorption]. 84 87

Twenty-eight Sioux and 29 Saluteaux Indians from a southern and an isolated northern Manitoban community were screened for lactose malabsorption; 55 were also screened for sucrose tolerance. Sixty percent of the subjects were lactose malabsorbers; the incidence increased with age. Lactase deficiency appeared, on the average, between 8 and 15 years of age. About 45% of the subjects were lactose intolerant. Malabsorbers who did not regularly drink milk had the highest symptom scores. The northern subjects consumed significantly more lactose and sucrose than the southern subjects. Two Sioux children were sucrose malabsorbers. It was hypothesized that the significantly greater sucrose consumption by the Saulteaux subjects were responsible for their markedly higher blood glucose curve following the sucrose tolerance tests. Dietary sucrose increases jejunal sucrase activity and the intestinal transport of glucose and fructose. Three of eight children less than 4 years were lactose malabsorbers; hence, medical personnel treating noninjective diarrhea in Indian children should examine for lactase deficiency. It was recommended that vitamin D fortified milk supplements to Indian school children be continued and that the milk be treated so as to reduce abdominal symptoms in the intolerant individuals.
 ...
PMID:Disaccharide consumption and malabsorption in Canadian Indians. 85 12


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