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H Carchon

Publications and source records attributed to H Carchon.

30 records · Page 2Linked to original sources
PubMed1988

13CO2 breath test using naturally 13C-enriched lactose for detection of lactase deficiency in patients with gastrointestinal symptoms.

A 13CO2 breath test using naturally enriched 13C-lactose as a substrate was performed in 47 patients with chronic abdominal pain or chronic diarrhea, taken from a population with a low prevalence of primary acquired lactase deficiency. The cumulative 13CO2 excretion 4 hours after 13C-lactose intake was compared with the H2 breath excretion and with jejunal lactase activity. A physiologically significant relation was found between the cumulative 13CO2 excretion (at 4 hours) and lactase activity, 14.5% 13CO2 excretion being the best cutoff point for discrimination between patients with low and normal lactase activity. The 13CO2 breath test was found to be more sensitive (0.84 versus 0.68) and more specific (0.96 versus 0.89) than the H2 breath test in detecting low jejunal lactase activity. Concordant results of both breath tests performed simultaneously give a reliable picture of the lactose absorption status of the patient. Discordance in results of 13CO2 and H2 lactose breath tests, if not explained by history, indicates in which patients a jejunal biopsy should be performed. If lactase activity and morphology of the biopsy are normal, other causes of discordance must be investigated.

Abdomen↗
PubMed1984

Positive 14CO2 bile acid breath test in elderly people.

The 14CO2- glycylcholate breath test (also called the bile acid breath test) was performed in a group of 42 normal young volunteers (group A), a group of 25 elderly subjects in apparently good health (group B) and a group of 22 hospitalized geriatric patients presenting with weight loss (group C). The 95 percentile value of the cumulative 14CO2 excretion at the third and the sixth hour in group A was taken as the limit for normal values for 14CO2 excretion. Using these criteria 56% of group B subjects and 50% of group C patients were considered abnormal at the third hour, whereas at the sixth hour these percentages were 56% and 54%, respectively. Repetition of the bile acid breath test after antibiotic treatment in the hospitalized group suggested that bacterial overgrowth in the small intestine was responsible for the abnormal 14CO2 breath test in the elderly persons. However, the large number of abnormal tests in healthy elderly people, not complaining of any gastro-intestinal discomfort, indicates that bacterial overgrowth may remain asymptomatic and that an abnormal test does not necessarily mean that the symptoms of a patient are to be ascribed to this finding.

Adult↗
PubMed1979

Digestion of gliadin peptides by intestinal mucosa from control or coeliac children.

Gliadin, subsequently treated with pepsin, trypsin and pancreatic extract was further digested by small-intestinal mucosal homogenates from 10 control or 8 coeliac children. The amino acids liberated in the incubation mixture were measured and corrected for mucosal damage. In accordance with the data from the literature on adults, the total amount of amino acids released from gliadin peptides by the intestinal mucosa from children with active coeliac disease is significantly lower than that by the mucosa from control subjects. Qualitatively, however, no significant differences for the individual amino acids are observed with the exception of glutamine and proline, so that damaged coeliac mucosa liberates relatively more glutamine but less proline.

Amino Acids↗
PubMed1975

Purification and properties of coffee-bean alpha-D-galactosidase.

A purification method for alpha-D-galactosidase from Coffea canephora is described. Two enzymes, alpha-D-galactosidases I and II, having molecular weights of 28,000 and 36,500, respectively, were found and extensively purified. The reaction mechanism of alpha-D-galactosidase II was studied. The enzyme hydrolyzed aryl and alkyl alpha-D-galactopyranosides and was severely inhibited by excess of these substrates. No inhibition occurred with raffinose. The influence of para substituents on the reaction rate of phenyl alpha-D-galactopyranosides, the effect of added alcohols, and the non-competitive inhibition by methyl alpha-D-galactopyranoside were investigated. A two-step mechanism with the formation of an enzyme-galactosyl complex is proposed. With aryl galactopyranosides, the reaction of the enzyme-galactosyl complex with water is rate-limiting. Influences of the substituents on the inhibition constant were investigated by linear free-energy relationships, and significant correlations between this constant and electronic parameters could be calculated. The influence of pH on the reaction is complex.

Aluminum↗
PubMedDate not supplied

Small intestinal brush border enzymes in cystic fibrosis.

The study concerns the maltase, saccharase, lactase and alkaline phosphatase activity in small intestinal biopsy specimens from 61 consecutively admitted, untreated, Caucasian cystic fibrosis patients. A group of 319 age matched controls admitted during the same time period for undefined gastrointestinal or nutritional disorders acted as the controls. In order to eliminate morphological damage as a confounding factor, the enzyme activities were studied in small intestinal biopsy specimens having both normal stereomicroscopic and histological features. It was shown that neither maltase nor saccharase activity was different in the two groups, in contrast to lactase and alkaline phophatase activity, that was significantly lower in cystic fibrosis patients. The differences could not be explained by the nutritional status as judged by the body mass index. Lactase activity is known to be easily affected by numerous enteropathies. As the information on alkaline phosphatase activity is limited, the low activity is discussed in more detail. Taking into account the literature data, the low alkaline phosphatase activity is tentatively attributed either to enhanced release from the brush border or to the faulty handling of alkaline phophatase protein in the post-golgi compartments secondary to the accumulation of incorrectly glycosylated CFTR in the same cell structures.

Alkaline Phosphatase↗