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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The suitability of the simultaneous azocoupling reaction with 1-naphthyl-beta-D-glucoside and hexazonium-p-rosanilin in the detection of the activity of lactase (or lactase-beta-glucosidase complex) in jejunal biopsies of patients with various forms of the malabsorption syndrome was tested. Results were compared with those obtained with the indigogenic method using 4-Cl-5-Br-3-indolyl-beta-D-fucoside which is the method of choice. Both methods gave identical results as far as the relative intensity of the brush border staining was concerned. The azocoupling method applied in unfixed cold microtome sections can be recommended for the routine diagnostics of the malabsorption syndrome when the indolyl substrate is not available.
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PMID:Suitability of the azocoupling reaction with 1-naphthyl-beta-D-glucoside for the histochemical demonstration of lactase (lactase-beta-glucosidase complex) in human enterobiopsies. 5 35

Thirty-six hospital in-patients in London had breath-hydrogen concentrations measured after 50 g lactose were given orally; in 23 or them serial blood glucose concentrations were also estimated. Eight had tropical malabsorption (TM), 14 were Europeans with no detectable disease (normal group) and 14 who also had no detectable disease, were from ethnic groups known to have a very high incidence of genetically determined adult hypolactasia (hl). In 21 of them breath-hydrogen concentrations were also measured after 33.5 g of lactulose were given orally. There was a good inverse correlation between breath-hydrogen production and blood-glucose rise after lactose. Correlations between the first appearance of hydrogen (T) and the area under the hydrogen curve between 0 and 120 min (A) were inversely significant both for lactose and lactulose. Mean T was earlier and mean A greater for lactose compared with lactulose. Correlation between individual values for A after lactase and after lactulose was significant. Indirect measurements of lactase are of no value in either detecting or assessing the severity of TM; that is largely due to the very high incidence of HL in individuals exposed to that disease.
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PMID:Breath hydrogen concentrations after oral lactose and lactulose in tropical malabsorption and adult hypolactasia. 9 20

The degree of which the ability to absorb lactose can be regained after recovery from an acute episode of severe malnutrition is in doubt. Lactase activity was indirectly assessed by means of a standard lactose tolerance test (2 g lactose per kilogram of body weight) in 71 Peruvian Mestizo infants and children (age 5 to 55 months) who had suffered such an episode. All were studied just before discharge after several months of hospital rehabilitation, during which linear growth and weight gain had accelerated and signs of significant malabsorption of other nutrients had disappeared. Only 39% of the total group had a positive test (delta blood glucose greater than 25 mg/dl); there was a decreasing proportion of positive responders with increasing age. No difference in response attributable to type or severity of malnutrition was found. Comparison of the present data with previous data from children in the same community who had never been acutely malnourished suggests that acute malnutrition may hasten the permanent decline of lactase activity normally expected later in life.
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PMID:Effect of an episode of severe malnutrition and age on lactose absorption by recovered infants and children. 10 90

General evidence of malnutrition such as loss in body weight associated with intestinal parasitism has been attributed to decreased food intake, to intestinal malabsorption, and to change in host basal metabolism. To establish the relative importance of these factors in this regard, rats with trichinosis were studied. The weights of infected and uninfected animals were followed after being placed on one of three feeding regimens for 1 week--stock diet ad libitum, intraduodenal nutrition, and intravenous nutrition. Infected rats on a stock diet lost weight whereas those on the other two regimens maintained the same weight pattern as uninfected counterparts. The maintainance of body weight occurred despite alterations at the level of the intestinal brush border as indicated by a depression of intestinal disaccharidase activities (sucrase and lactase) and by reduction of monosaccharide absorption (measured as accumulation of beta-methyl glucoside) in the proximal, heavily infected region of the small intestine. There was no compensatory increase in enzyme activity nor in the absorptive capacity in the distal gut. Results support the conclusion that inadequate oral food intake rather than changes in basal metabolism or intestinal pathophysiology accounts for weight loss during the intestinal phase of infection.
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PMID:Enteral and parenteral feeding to evaluate malabsorption in intestinal parasitism. 11 Jan 62

It has been suggested that dietary lactose may reduce the intestinal absorption of fat and protein in individuals with lactase deficiency. On the other hand, it is known that a high carbohydrate diet increases serum lipids. The purpose of this study was to examine whether there are differences in the fasting serum lipid and protein concentrations between people with lactose malabsorption and people with normal lactose absorption. Therefore in the connection of a family study serum lipids and proteins were measured in 409 subjects belonging to 11 families. Of these 288 were relatives of the 11 index persons and 121 were spouses or relatives of the spouses. The weight, height, and milk consumption of each person were recorded. When the age, sex, relative weight and milk consumption effects were taken into account there was a statistical difference between the lactose malabsorption and lactose absorption groups for the concentration of serum triglycerides, but not for the other variables. Besides, serum triglyceride values of over 200 mg/100 ml were significantly fewer in people with lactose malabsorption. It was hypothesized that increased intestinal motility may disturb the absorption of fats and cause the observed difference at least in the Finnish population.
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PMID:Serum lipids and proteins in lactose malabsorption. 19 65

Physiological bases of digestion and absorption of carbohydrates are reviewed, as a preliminary step, in order to draw a general scheme of its patholophysiology. Clasification of different types of carbohydrate malabsorption is presented. Various exploration methods are discussed in terms of autors' own experiences. Relationship between a sugar screening test, faecal lactic acid contents and a simplified lactose tolerance test, is described in detail. Systematic diagnoses of these diseases are established. Different clinical pictures are reviewed. It is not yet well defined if a starch malabsorption can be caused by either a primary or secondary duodenal amylase deficiency. The clinical forms of congenital sucrose-isomaltose intolerance may be more attenuated than its classical form; incertain cases, secondary sucrose intolerance may also be present due to mucosa anatomic lesions. Maltose malabsorption has no clinical implications. As compared to other alpha-glycosidades, the trehalase activity has been not more affected by not using trehalose in feeding. Primary congenital lactase deficiency is not frequent, whereas secondary forms as much more usual and appear, in primary malabsorption syndromes and in the coeliac disease, very often along with clinical tolerance to lactose. In Spain, lactose nonabsorbers in 16.5% for adults 11.2% for adolescents and 18.3% for children, meaning, that it is being favored by environmental factors in the latter. The unspecified sugar malabsorption during the child's first year is still the most frequent cause of carbohydrate intolerance in children and, although certain progress has been achieved in its diagnosis and therapy, its pathogenic mechanism is not satisfactorily known yet.
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PMID:[Malabsorption of carbohydrates in children (author's transl)]. 23 44

Histochemical examination of aspiration biopsy specimens of the duodenum in 8 healthy volunteers and 23 patients with various gastrointestinal disorders revealed no characteristic abnormality except for a rather frequent absence of the activity of disacharidases especially of lactase. A distinct difference of disacharidase was established between the duodenum and the jejunum in some individuals. A systematic study of different levels of the upper gastrointestinal tract established the fact that the activity of brush border enzymes of enterocytes starts to appear in individually different parts of the duodenum and sometimes even as low as in the jejunum. The distribution of lysosomal enzymes and the activity of dehydrogenases display differences as well. Consequently specimens from different parts of the duodenal and jejunal mucosa are not equivalent and cannot be used alternatively for diagnostic purposes. Biopsies of duodenal mucosa are not adequate for the diagnosis of the malabsorption syndrome.
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PMID:Histochemistry of the human duodenal mucosa with special reference to the gradient of activities of the brush border enzymes. 29 9

One hundred and fifty subjects were studied in a double blind fashion to determine the relationship between lactose malabsorption and milk lactose intolerance. Each participant received 250 ml of a different type of milk on 3 consecutive days. Milk A contained no lactose, milk B had 12.5 g, and milk C contained 37.5 g of lactose. After the experiment was completed each subject was classified with a lactose tolerance test as having "sufficient" or "insufficient" lactase activity. Milk A produced no gastrointestinal symptoms in either sufficient or in insufficient persons. Milk B produced symptoms in 3.8% of sufficient and 37.1% of insufficient individuals, and Milk C induced symptoms in 7.6% of sufficient and 83.5% of insufficient subjects. These differences are very highly significant (P less than 0.0001). It is concluded that lactose-intolerant subjects are indeed milk-intolerant and that the frequency with which symptoms occur in persons with lactose malabsorption increases in direct relation to the lactose content of the milk.
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PMID:Double blind study of milk lactose intolerance. 34 53

The diagnostic value of 1-14C-lactose breath test was compared with the standard lactose tolerance test and lactase assay in jejunal biopsies in 16 control subjects, 14 patients with lactase deficiency (LD) proven by lactase assay and 20 patients with irritable bowel syndrome (IBS). 14CO2 specific activity in the 2-hr breath collection after administration of 1-14C-lactose (5 muCi) provided a satisfactory separation between the control and LD group. Values were 7.0 +/- 2.0% dose administered/mmoles 14CO2 X 10(-3) (mean +/- SD) in the control group versus 2.1 +/- 1.5 in LD (P less than 0.001) versus 4.9 +/- 2.3 in IBS (P less than 0.01). 1-14C-lactose breath test was superior to standard lactose tolerance test in specificity (P less than 0.05) and provided a satisfactory correlation between 14C-lactose absorption and lactase assay (r = 0.77). The prevalence of LD in IBS was 40% by the breath test and 35% by lactase assay, suggesting that lactose malabsorption may play a role in the symptoms in the population of some patients with IBS. It appears that 1-14C-lactose breath test is a sensitive, specific and accurate method for the diagnosis of LD in clinical practice and suitable for large scale epidemiological surveys.
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PMID:Lactase deficiency--a comparative study of diagnostic methods. 41 Feb 88

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.
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PMID:Inhibition of human intestinal alpha-glucosidehydrolases by a new complex oligosaccharide. 44 22


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