Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.108 (lactase)
 2,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During the past several years there have been many reports of alternative dietary therapies for primary and secondary lactose intolerance. We have learned that it is useful to feed through most episodes of mild diarrhea that previously would have been treated with clear liquid diets. Infant formulas, including both soy-protein and hydrolysate formulas with specially designed carbohydrate, protein, and fat components, are available to treat the infant with diarrheal syndromes and secondary lactase deficiency. Also, the diet can be supplemented with lactase. Specialized lactose-reduced products as well as cultured and fermented dairy products may be used in varying degrees for lactose-intolerant children. The ingestion of milk with food and fiber components in the diet has also been shown to improve symptoms of lactose intolerance. This review summarizes the essentials of diagnosis of and dietary therapy for lactose intolerance. Our findings indicate that a number of specialized formulas and products are available for successful dietary management of lactose intolerance in infants and children.
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PMID:Dietary treatment of lactose intolerance in infants and children. 196 Mar 50

The Authors carried out a Rotavirus investigation on the stools of 6057 children admitted in the Department of Pediatric and Pediatric Gastroenterology of Catania University, during the years 1984-1988. The stool samples of 264 children were found positive for Rotavirus. While 204 children presented gastrointestinal symptoms with diarrhoea, 12 had subclinical signs, 26 presented only respiratory symptoms and 22 had no clinical symptomatology. Moreover 122 children with diarrhoea had associated respiratory manifestations. In this study the authors punctualized that: 1) the most interested age was the first year of life; 2) there was no evidence in seasonal variations; 3) the respiratory tract was involved in high percentage of children (59.8%); 4) a transient lactase deficiency was supposed in every children with watery diarrhoea, but it was demonstrated only in 21 (10.3%).
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PMID:[The clinical pictures of rotavirus infection in childhood. Studies on the admissions to the Clinica Pediatrica di Catania in 1984-1988]. 196 27

In order to develop an experimental model of symptomatic cryptosporidiosis in an immunosuppressed mammal, we investigated the pathophysiology of infection with Cryptosporidium and the humoral and cellular host responses in rnu/rnu (athymic) rats and their heterozygous (rnu/+) littermates by challenging suckling rats with greater than or equal to 2.5 x 10(6) Cryptosporidium oocytes oro-gastrically. Normal and immunodeficient animals were followed for onset and duration of infection (fecal oocysts), physiologic consequences (diarrhea, impaired weight gain, brush-border enzyme activities), and immunologic response (both B- and T-lymphocyte-mediated). Homozygosity for the rnu gene was associated with protracted cryptosporidial infections; shedding for up to 52 days occurred, and delay in weight gain was noted in rnu/rnu-infected compared with rnu/rnu-uninfected rats (p less than 0.05). In contrast, cryptosporidial challenge of rnu/+ rats resulted in self-resolving infections, occasionally with transient diarrhea lasting four days or less occurring 10-15 days after oro-gastric challenge. The latter animals mounted a cell-mediated immune response to Cryptosporidium: three months after challenge, five of five rnu/+ rats demonstrated positive skin test responses to a subcutaneous 3.5 micrograms dose of cryptosporidial antigen. Further, sera from 6 rnu/+ rats taken two to three months after oro-gastric oocyst challenge exhibited specific anticryptosporidial immunoglobulin binding (A405 = 0.96), compared to that of seven uninfected rnu/+ controls (A405 = 0.09, P less than 0.02). Macromolecules of 150, 105, and 88 kD in the Cryptosporidium antigen preparation were bound by serum immunoglobulin from previously infected, recovered rnu/+ rats. Two brush-border enzymes (lactase and alkaline phosphatase) were markedly reduced in the ileum 8-10 days after oro-gastric challenge in rats with diarrhea and oocyst shedding. We find the rnu/rnu (athymic, nude) rat provides a useful model for study of prolonged cryptosporidial infection with impaired weight loss, brush-border enzyme alteration and intermittent diarrhea. These studies further suggest that a T-lymphocyte population is involved in recovery from Cryptosporidium infection and that this recovery is associated with both cellular and humoral immune responses to specific cryptosporidial antigenic macromolecules. This model should open further avenues for the study of the pathogenesis and protective immunity in cryptosporidial infection.
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PMID:Intestinal cryptosporidiosis: pathophysiologic alterations and specific cellular and humoral immune responses in rnu/+ and rnu/rnu (athymic) rats. 199 41

Several alterations of the small-intestinal morphology and function have been documented after alcohol ingestion. There are morphologic changes macroscopically and microscopically after acute alcohol administration in the proximal part of the small intestine, which are quickly reversible. There are no macroscopic changes and, in most patients, very discrete light microscopic changes in the small intestine after chronic alcohol ingestion. The ultrastructural changes are, however, profound, as seen by both transmission and scanning electron microscopy. The permeability is probably increased, permitting entrance of possible noxious agents, which may explain some of the extraintestinal tissue damage observed in chronic alcoholism. The transit is increased, at least after acute alcohol administration, perhaps contributing to the diarrhea commonly seen after heavy drinking. Several of the enzymes located in the brush border are affected; lactase activity can be depressed and perhaps result in a transient milk intolerance in predisposed individuals. The activity of GGT is increased and may partly account for the GGT elevation in serum after heavy drinking. Other enzymes, such as Na(+)-K(+)-ATPase, can be inhibited and result in a decreased absorption of substances that require active, energy-dependent transport mechanisms. The secretion of water and electrolytes may be increased (an effect on cAMP?). The absorption of several nutrients, vitamins, and other elements is disturbed. The bacterial flora is increased and changed, which may give rise to symptoms and also increase the production of acetaldehyde by bacterial metabolism of ethanol. Acetaldehyde is more toxic than ethanol, and an increased concentration of acetaldehyde can possibly accentuate the damage to the liver and other organs. The bacterial overgrowth can possibly cause endotoxinemia. Although studies on alcohol-related intestinal alterations have been relatively sparse, the acute and chronic effects of alcohol thus seem to be considerable. From available results it is, however, difficult to draw any definite conclusions about the clinical importance of many of the findings. Future research will need to study the relationship between, for example, the chronic morphologic changes, the absorptive dysfunction, and permeability alterations, on the one hand, and the gastrointestinal symptoms, the extraintestinal damage, and various deficiencies, on the other hand.
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PMID:Alcohol and the small intestine. 200 95

Breath-test was performed for diagnosis of lactose malabsorption in 50 Gabonese children of normal nutritional status, aged 5 to 15 years, with parasites in stools, but without diarrhoea or digestive symptoms. Control group was unparasitized and consisted of 17 children and 18 young adults living in the same area. Parasites discovered by stool examination were Ascaris lumbricoides in 76% of parasitized children, Trichuris trichiura in 58%, Giardia in 24%, Entamoeba histolytica in 20%, Schistosoma intercalatum in 16% and Necator Americanus in 14%. Children were given a 10 g lactose load and adults 20 g. Lactose malabsorption was discovered in 64% of parasitized patients and in 63% of unparasitized. Ten of 12 (83.3%) of Giardia infected children had a lactose malabsorption (no significant difference). These data show that decrease of lactase activity in African children is not related to the presence or to the importance of intestinal parasitism, except for Giardia infestation, if nutritional status is normal.
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PMID:[Intestinal parasites and lactose malabsorption]. 207 8

Although claims for health and nutritional benefits have been made for lactic acid bacteria in fermented dairy products for nearly a century, the nutritional and therapeutic value of these organisms is still controversial. This article will review the scientific basis of these claims. There are numerous studies showing fermentation of food with lactobacilli increase the quantity, availability, digestibility, and assimilability of nutrients. The basis for this conclusion comes from direct measurements of vitamin synthesis and from increased feed efficiency when fermented products are fed to animals. There have been a number of studies showing that various fermented dairy products lower serum cholesterol levels in humans and animals. These studies are reviewed and the validity of these findings are assessed. A summary of the evidence indicating that lactase deficient individuals can eat yogurt and the mechanisms involved in this toleration is reviewed. The role of fermented dairy products in inhibiting tumor growth and chemically induced tumors in animals is discussed and the possible mechanisms involved in this protective effect are reviewed. Fermented dairy products and lypholized lactobacilli preparations have been shown to be useful in treating and preventing various intestinal infections including; salmonellosis, shigellosis and antibiotic induced diarrhea. In this context a specific lactobacillus designated GG has been shown to be useful in treating recurring diarrhea caused by a toxin produced by Clostridium difficile.
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PMID:Lactic acid bacteria and human health. 210 88

Brush border lactase, sucrase and glucoamylase activities were assessed in jejunal mucosal biopsy specimens from 34 children (median age 11 months; range 1.5-38) having protracted diarrhoea with failure to thrive and 8 well nourished children with normal jejunal mucosal histology (median age 10.2 months; range 2-37). All enzymes showed progressive decrease in activity which was directly in relation to increasing degree of mucosal injury (P less than 0.002). Lactase was significantly reduced even in patients with protracted diarrhoea and normal mucosa (P less than 0.05). Glucoamylase and sucrase were significantly reduced only in the presence of mucosal injury (P less than 0.01). Our data suggest that most children with protracted diarrhoea may not tolerate lactose containing feeds and may need lactose-free diets preferably based on starch. A small number of children with protracted diarrhoea, who have severe mucosal injury may not be able to handle even starch and may require diets based on short chain glucose polymers. The findings of this study, need to be corroborated with well-controlled metabolic balance studies.
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PMID:Intestinal glucoamylase & other disaccharidases in children with protracted diarrhoea. 211 15

Lactose-intolerant children manifest diminished or nonexistent intestinal lactase activity, resulting in flatulence, abdominal pain, and diarrhea. To assess the hydrolytic capability of lactase-containing tablets taken immediately before oral lactose challenge, we studied 18 children previously identified as being lactose intolerant and having no underlying organic gastrointestinal disease. Subjects had a mean (+/- SEM) age of 11.4 +/- 3.4 years; 72% were male. At time of the study, lactase-containing tablets or placebo tablets were ingested (double-blind) immediately before drinking a solution of lactose. Breath samples were obtained for hydrogen analysis at 30-minute intervals during a 2-hour period, and clinical symptoms were monitored. In lactose-intolerant patients, hydrogen production was significantly greater following placebo (maximum hydrogen excretion, approximately 60 ppm) compared with lactase-containing tablets (maximum hydrogen excretion, 7 ppm). Increased hydrogen production was associated with clinical symptoms including abdominal pain (89% of subjects following placebo ingestion), bloating (83%), diarrhea (61%), and flatulence (44%). These results indicate, therefore, that coingestion of lactose and lactase-containing tablets significantly reduces both breath hydrogen excretion and clinical symptoms associated with lactose intolerance.
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PMID:Beta-galactosidase tablets in the treatment of lactose intolerance in pediatrics. 212 19

A histochemical study of the time course of the appearance and location of lactase and alpha-glucosidase (used to detect sucrase and maltase) activities was carried out on control and rotavirus-infected mice from 7 to 14 days old. The overall pattern of enzyme activity was in agreement with previous quantitative studies on the activities of these enzymes. No evidence was obtained to support the idea that lactase deficiency was the result of repopulation of villi (denuded of lactase-producing villus cells) with immature lactase-negative cells. Low lactase activity was more likely to reflect profound changes in metabolically crippled cells, and recovery of lactase activity with recovery of normal metabolic functions. The location of enzyme activity to brush border regions rather than the cytoplasm of villus enterocytes enhances the significance of previous quantitative studies on these enzymes. The timing and duration of diminished lactase activities were such that they were unlikely to cause the induction or perpetuation of diarrhea in murine rotavirus diarrhea. The appearance in infected animals of alpha-glucosidase 3 days earlier than normal indicates that, in addition to reversible changes seen with lactase, developmental changes were accelerated that affected both crypt and villus cells.
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PMID:Disaccharidase activities in small intestine of rotavirus-infected suckling mice: a histochemical study. 212 44

Nucleic acid synthesis in tissues of rapid growth is preferentially done using dietary purines and pyrimidines via the salvage pathway. In the case of a low protein intake, dietary nucleotides may be semiessential for cell replication of gut, lymphocytes, and bone marrow, and especially in those intestinal diseases in which the mucosa is altered, dietary nucleotides may have a role in intestinal development. The effect of dietary nucleotides on intestinal weight and length, gut mucosal weight, intestinal protein and DNA contents, and lactase, maltase, and intestinal mucosal activities was assessed in a controlled way. Weanling (21-day-old) rats were separated into two groups of 36, each receiving blindly a basal diet containing glucose polymers (C) or a basal diet with lactose as the main carbohydrate (L) for 15 days. Those fed with L developed a syndrome of chronic diarrhea and malnutrition. Ten rats of each group were sacrificed at that time. The rest of the animals of each group were separated into two subgroups. The first was fed with the C diet and the second with the C diet supplemented with 50 mg/100 g of each of the following nucleotides: AMP, GMP, CMP, UMP, and IMP (CN). Thus the subgroups CC, CN, LC, and LN were formed. Rats were sacrificed after 4 weeks and gut separated into three segments corresponding to duodenum, jejunum, and ileum. Analysis of variance was used to compare the effect of diet or segments. DNA and lactase, maltase, and sucrase activities increased in the LN group with respect to LC especially in jejunum and ileum but there were not any differences between CC and CN.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of dietary nucleotides on intestinal repair in rats with experimental chronic diarrhea. 212 43


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