Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Macroamylasemia is a benign acquired condition, characterized by a serum amylase unusually large in molecular size that has been found to occur in apparently healthy humans as well as in a variety of diseases including liver disease, diabetes, cancer malabsorption and autoimmune disorders. Most commonly macroamylasemia results from the formation of immune complexes between amylase and immunoglobulins. We describe the first case of an association between macroamylasemia/hyperamylasemia and rheumatoid arthritis characterized by the absence of immunoglobulins, as amylase binding globulins, within the macroamylase complex. Failure to identify macroamylase as the cause of unexplained but benign hyperamylasemia correctly, can lead to costly studies (e.g. ultrasonography, computerized tomography) to rule out pancreatic disease, and could induce prescription of unnecessary elemental diets and replacement therapies, as reported in our patient.
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PMID:Macroamylasemia: a possible cause of unexplained hyperamylasemia in rheumatoid arthritis. 753 58

The activities of pancreatic enzymes decrease during their passage from the duodenum to the terminal ileum, but degradation rates of individual enzymes are different. Whereas lipase activity is lost most rapidly, proteases and amylase are more stable. The mechanism by which lipase activity is destroyed is proteolysis, mainly by the action of chymotrypsin. This mechanism is also operative in patients with chronic exocrine pancreatic insufficiency. It explains why fat malabsorption develops earlier compared with protein or starch malabsorption. The substitution of lipase is also more difficult than that of other enzymes, because it is more rapidly destroyed by proteases. Conversely, inactivation of proteases improves intraluminal activity of lipase not only in healthy individuals but also in patients with chronic pancreatitis. Other factors that contribute to problems in lipase substitution therapy include acid-peptic destruction of unprotected enzyme preparations and unphysiological particle sizes of enteric-coated capsules or pellets. Recent data suggest that the adaptation of the diameter of enteric-coated pancreatin micropellets into the range that permits gastric emptying in synchronicity with the meal improves their digestive efficacy.
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PMID:Fate of pancreatic enzymes in the human intestinal lumen in health and pancreatic insufficiency. 769 30

The presence or absence of a normal small bowel is evidently important for the digestion and absorption of nutrients in humans. The importance, however, of the large intestine as an organ with digestive potential and an ability to salvage energy is much less appreciated. Whereas the bacterial fermentation of plant polysaccharides, with the production and absorption of short-chain fatty acids (SCFAs), contributes 60-90% of all the energy requirements in plant-eating animals, the colonic fermentation in humans is of minor importance for nutrition, with only 5-10% of the energy requirements available from colonic digestion of starch, nonstarch polysaccharides, and protein not absorbed in the small bowel, if the intestine has a normal length and function. In contrast, the digestive resource of the large bowel might be important for people with reduced upper-gut function and with the malabsorption of large amounts of dietary nutrients to the cecum, e.g., in patients with short bowel. The substrates available for bacterial fermentation and for the maintenance of the colonic flora are largely starch and nonstarch polysaccharides (dietary fiber). Whereas nonstarch polysaccharides are undegradable by amylase in the small intestine, starch is hydrolyzed by amylase, but with very different rates and to very different degrees dependent on the origin and structure of the starches. The unequal susceptibility to amylase explains the different amount of starch that is not absorbed in the small intestine. The rate of colonic fermentation of starch has also been shown to relate to the rate of starch hydrolysis by amylase.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Digestive processes in the human colon. 774 42

Pancreatic enzyme extracts have been used for several decades to decrease maldigestion of macro- and micronutrients due to pancreatic insufficiency and to alleviate various abdominal symptoms, including the pain of alcohol-induced chronic pancreatitis and distal intestinal obstruction. Decreasing nutrient maldigestion and malabsorption in pancreatic insufficiency is of additional critical importance because improvement in nutritional status reduces morbidity and mortality. For example, pancreatic sufficient patients with cystic fibrosis (CF) demonstrate a slower decline in pulmonary function. In spite of the recognized importance of pancreatic enzymes, several problems exist with current preparations, and as newer enzyme preparations are marketed, proper evaluation becomes critical. There is a clear need to optimize the constituents of enzyme preparations, improve manufacturing processes, and find better sources of enzymes. Other issues that need addressing include standardization of the ratios of enzymes (lipase, amylase, protease) in these products; the stability of the enzymes at room temperature; the shelf life of the finished product; whether there are significant batch-to-batch differences; and the need for a USP reference standard.
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PMID:Enzyme therapy for pancreatic insufficiency: present status and future needs. 810 63

We evaluated three acid-resistant pancreatic enzyme preparations by in vitro assays, and by comparing degree of steatorrhea, creatorrhea, fecal wet weight, and stool energy losses in a randomized crossover study of patients with pancreatic insufficient cystic fibrosis. Aims of the study were to assess (a) the most practicable and reliable indicator of malabsorption; (b) the variation in enzyme batch potency; (c) the decline in enzyme batch potency with prolonged shelf life; and (d) the relative bioefficacy of the different preparations. In the in vivo study, absorption of energy, nitrogen, and fat did not differ when comparing the three preparations at roughly pharmaceutically equivalent doses, but when expressed per capsule of pancreatic supplement ingested, absorption reflected relative enzyme content, favoring the higher potency preparations. Although steatorrhea was reasonably controlled by these preparations, stool energy losses varied from 800 to 1,100 kJ per day, suggesting greater attention be paid to overall energy absorption rather than absorption of individual nutrients. In addition, fecal energy loss correlated more closely with fecal wet weight (r = 0.81; p < 0.05) than with steatorrhea (r = 0.40; ns), such that 1 g wet feces = 8.37 kJ (+/- 0.14). In vitro enzyme potency varied markedly between batches of the same brand, and also a decline of up to 20% in amylase, lipase, and trypsin activity was noted over an 8-month period for each batch. Both observations have clinical implications at times of represcription. Finally, the higher potency preparations were more effective per capsule and reduced capsule dosage is therefore attainable.
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PMID:Comparative in vitro and in vivo studies of enteric-coated pancrelipase preparations for pancreatic insufficiency. 814 97

To determine the prevalence of short polymers of glucose and starch malabsorption caused by small intestinal glucoamylase deficiency in children with chronic diarrhea, we studied small bowel biopsy specimens from 511 children (aged 1 month to 9 years) with chronic diarrhea evaluated at 54 medical centers. Glucoamylase and disaccharidase (lactase, sucrase, maltase, and palatinase) enzyme assays were performed. Of the 511 children, 15 had glucoamylase deficiency. Six who had significant small intestinal mucosal injury and disaccharidase deficiencies were defined as having secondary glucoamylase deficiency; the other nine patients with normal mucosal morphologic features were defined as having primary glucoamylase deficiency. Secretin tests showed normal pancreatic amylase values for age in all seven children tested. Four of them had abnormal findings on tolerance tests for starch and short polymers of glucose (rise in blood glucose concentration: < 20 mg/dl) and reducing substances in stools, and three of these four had symptoms of intolerance (abdominal distention, flatulence, and diarrhea). All seven patients responded to a starch elimination diet. After reintroduction of a starch diet, diarrhea recurred in four patients; this was alleviated 48 hours after reelimination of starch. We conclude that intestinal glucoamylase deficiency is present in some patients with chronic diarrhea.
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PMID:Small intestinal glucoamylase deficiency and starch malabsorption: a newly recognized alpha-glucosidase deficiency in children. 815 67

Giardia lamblia localize and multiply in the small intestine and may cause acute or chronic diarrhoea with malabsorption of fat, protein and other nutrients. Abnormal pancreatic function has been documented in giardiasis and trophozoites directly inhibit pancreatic lipase activity in vitro. The aim of this study was to examine the effect of Giardia trophozoites on pancreatic trypsin, chymotrypsin and amylase activity in vitro. Axenically cultured Giardia trophozoites (Portland-1 stock) were incubated with a range of concentrations of trypsin, chymotrypsin and amylase and enzyme activity assayed over time. Tryptic activity was decreased after incubation with Giardia trophozoites. This reduction was time dependent and linear over the incubation period of 2 h. At a trypsin concentration of 18 BAEE units/ml, there was a 35.5 +/- 4% reduction in enzyme activity after 2 h compared to controls. The total amount of activity lost was proportional to the initial trypsin concentration up to 185 BAEE units/ml. At this initial concentration, the activity was reduced by 46.5 +/- 3 units/ml after 2 h. Above this concentration, little further loss of enzyme activity was seen. To investigate the nature and specificity of this effect, similar experiments were conducted using killed trophozoites and with a related protozoan, Trichomonas vaginalis. No loss of enzyme activity was evident. Media previously incubated for 2 h with trophozoites did not diminish tryptic activity. Trophozoites had no effect on chymotrypsin or amylase activities over the range of concentrations tested.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The effect of Giardia lamblia trophozoites on trypsin, chymotrypsin and amylase in vitro. 848 60

Plasma chemistry and haematological studies were conducted on chickens with coccidiosis. Male White Leghorn chickens, of two weeks old, were inoculated with 5 x 10(4) Eimeria tenella sporulated oocysts or with 1 x 10(6) E acervulina sporulated oocysts. Blood samples were taken four, seven and 11 days after inoculation. A wet chemistry system was applied to measure the plasma activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma glutamyltransferase, creatine kinase, amylase and lactate dehydrogenase and the concentrations of creatine, total bilirubin, urate, total cholesterol, total protein, albumin, glucose and triglycerides. A dry chemistry system was applied to measure sodium, potassium, chloride and calcium. The number of red blood cells and packed cell volume were determined by a micro cell counter and blood pH was measured with a blood gas analyser. The erythrocyte count, packed cell volume, sodium and chloride levels in the chickens infected with E tenella were significantly (P < 0.05) lower than those of the uninfected controls. The significant decrease in blood pH of the chickens infected with E acervulina suggests malabsorption associated with duodenal lesions induced by the infection.
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PMID:Evaluation of plasma chemistry and haematological studies on chickens infected with Eimeria tenella and E acervulina. 925 31

The therapeutic effect of acarbose is generally attributed to inhibition of amylase and brush border glucosidases and consequent impaired digestion and absorption of carbohydrates. We have investigated the possibility that acarbose may also influence the rate of gastric emptying by comparing plasma glucose and gastrointestinal hormone responses to an oral sucrose load with and without acarbose in 11 healthy subjects. Gastric emptying was assessed indirectly by measuring circulating paracetamol concentrations following administration of paracetamol along with the sucrose load. Peak plasma glucose, insulin, and glucose-dependent insulinotropic polypeptide (GIP) responses were reduced when sucrose was given with acarbose. There was a significant reduction in post-sucrose paracetamol levels with acarbose suggestive of a significant delay in gastric emptying. The failure of acarbose to induce change in circulating paracetamol concentrations until after 60 min is indicative of a delay in gastric emptying rather than an osmotic malabsorption. The exaggerated and sustained release of glucagon-like peptide-1 (7-36)amide (GLP-1) seen when sucrose was given with acarbose may play a part in the inhibition of gastric emptying. This study indicates that a significant delay in gastric emptying may be an added mechanism contributing to the therapeutic effect of acarbose.
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PMID:Delayed gastric emptying occurs following acarbose administration and is a further mechanism for its anti-hyperglycaemic effect. 950 11

Amylase inhibition has gastrointestinal and metabolic effects that may aid in the treatment of diabetes and obesity. We tested whether 4 g of a commercially available wheat amylase inhibitor (WAI) affected postprandial carbohydrate (CHO) absorption and plasma glucose or hormones. Twelve persons (four lean and four obese nondiabetics and four obese type II diabetics) were studied on 2 separate days. After eating a weight maintenance diet (55% CHO, 20% protein, and 25% fat, as percentage of calories) for 3 days, subjects ate a breakfast containing 650 kcal, the same proportion of nutrients as calories, and in random order, either WAI or no WAI. Breath H2 and plasma glucose and hormones were measured every 15 and 30 min, respectively, for 7 h. WAI decreased the delta peak postprandial plasma glucose concentrations in 10 of 12 subjects (p < 0.05) and increased the breath H2 levels in 11 (p = 0.02); the increases in breath H2 were small, generally <20 ppm. No subject experienced a change in stools, diarrhea, or bloating. In response to WAI, gastric inhibitory peptide decreased (p < 0.05), peptide YY increased (p < 0.05), and there was a trend toward increased human pancreatic polypeptide (p = 0.07). Although WAI delays CHO absorption and reduces peak postprandial plasma glucose concentrations, overall CHO malabsorption is minimal (as reflected by breath hydrogen and hormones) and without symptoms. It, therefore, may be useful in treating type II diabetes mellitus.
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PMID:Acute postprandial gastrointestinal and metabolic effects of wheat amylase inhibitor (WAI) in normal, obese, and diabetic humans. 970 Sep 50


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