Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is postulated that the combination of a very low protein diet, with low pancreatic tryptic activity, plus the continual consumption of sweet potato trypsin inhibitors leads to inadequate proteolysis when a meal containing meat contaminated with C. perfringens type C and its beta toxin is consumed. The necrotizing pathogenic process concluding as segmental gangrene is set in motion by toxin produced under altered dietary conditions first by motor paralysis via beta toxin, followed by villous attachment and colonisation by ingested or resident C. perfringens type C in the gut. Necrobiosis is maintained by further toxin production which may be blocked in immune individuals. The endemicity of the disease is governed by the amount of C. perfringens type C in both the general and gut environments, the latter determined by dietary influences and the protein nutrition of the host. A hypothesis put forward is that the organism is carried and dispersed by the domestic pig and man becomes an incidental host. Infectivity only occurs when critical ecological factors exist in the small gut of humans. Prevention in the short term is possible with a toxoided vaccine using three injections given at one month and twelve month intervals.
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PMID:Pig-bel--a zoonosis? 73 66

Enterokinase initiates digestion of protein by conversion of trypsinogen into trypsin. The interactions between enterokinase and trysin were investigated in 6 patients with intractable diarrhea of infancy and 34 children with celiac disease. The six infants between 2 and 3 months with intractable diarrhea of infancy had reduced mucosal enterokinase activity (9.5 +/- 4.8muM per gram of protein per minute) and reduced intraluminal trypsin activity (2.9 +/- 0.7muM per gram of protein per minute) as compared with healthy controls (109 +/- 34.2muM per gram of protein per minute and 14.3 +/- 5.8muM per gram of protein per minute) respectively. The activities of all enzymes returned toward normal following treatment with intravenous alimentation. The mucosal morphology of all pretreatment biopsies in all cases showed Grade III atrophy which improved. These findings suggest that enterokinase deficiency and reduced intraluminal trypsin activity in intractable diarrhea of infancy may be one of the contributing factors to protein malabsorption and consequent malnutrition. Thirty-four children with celiac disease were between the age of 9 months and 13 years. The 11 newly diagnosed patients with celiac disease demonstrated Grade III to IV atrophy of the mucosa. The 23 patients with treated celiac disease on a gluten-free diet showed a normal to Grade II atrophy. In both treated and untreated celiac disease the enterokinase activities and the intraluminal trypsin activity were within normal limits. The enterokinase activity in celiac disease is near normal in contrast to the marked reduction noted in intractable diarrhea of infancy even though the intestinal mucosa shows marked morphological alteration and the disaccharidase activities are greatly reduced in celiac disease. After a prolonged alimentary fast of up to 26 days on intravenous alimentation, two patients with intractable diarrhea of infancy showed improvement in the activities of enterokinase and trypsin. These findings demonstrate that enterokinase and trypsin activities in the gut were present and improved in the absence of oral feeding.
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PMID:The interrelationship of enterokinase and trypsin activities in intractable diarrhea of infancy, celiac disease, and intravenous alimentation. 80 41

The zymograms of the digestive caeca and the intestine in seven species of Isopods are established. The glucidasic activities predominate. A relative proteasic poverty is noted as well as the absence of lipases however, the esterases exist. The enzymatic pattern of the gut suggests its participation in the alimentary digestion. The enzymes distribution allows us to establish relations with the food preference of the animals. Some particularities (trypsin, alpha and beta glucosidase) favour a comparison of the marine species with the supralittoral species on one hand and with terrestrial species on the other. This fact does not exclude however the systematic interest of the zymograms.
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PMID:[Comparison of the zymograms of isopod (Crustacea, Peracarides) digestive tubes]. 81 40

Intestinal perfusion methods with a nonabsorbable marker allow an exact quantitative determination of intestinal absorption and secretion provided that methodological pitfalls are avoided. A modified technique is applied to the simultaneous measurement of biliary and pancreatic secretion during and depending on emptying of a mixed test meal. A duodenal segment was perfused with an isotonic polyethyleneglycol solution (PEG). Reinjection of duodenal aspirates maintained a normal enterohepatic circulation of bile acids (interruption less than 10%). The perfusion was performed in healthy volonteers over a period of 12 to 24 hours, with three mixed formula meals containing 51CrCl3 as a marker ingested at conventional feeding hours. Influence of meal size was studied by means of a high caloric (40 Kcal/b. wt. per day) test meal. Patients with cholesterol gallstones and cirrhosis of the liver only received one formula test meal of 300 Kcal. Instead of concentrations output of trypsin, lipase, bile acids and cholesterol (the latter corrected for duodenal absorption) was calculated from the dilution of PEG in the duodenal juice and gastric emptying was determined by following quantitatively the flow of 51CrCl3. Gastric emptying can be expressed by a single exponential function over most of the time. Only the last 60-100 Kcals were expelled by the stomach at a faster rate. The daily biliary and pancreatic secretion depend indirectly on the amount of food ingested. But during the day light hours (with continuous meal flow), secretion was similar in high and low caloric subjects, while a significant difference became obvious during night hours corresponding to differences in gastric emptying time. Mean hourly output of bile acid, biliary cholesterol, trypsin and lipase is independent from meal size and secretion of pancreatic enzymes reaches the values close to those after maximal stimulation by i.v. CCK-PZ. Output of pancreatic enzymes does not differ in health and gallstone disease or cirrhosis of the liver respectively. Since during digestion in normals approximately one forth of the bile acid pool is secreted hourly into the gut, the number of daily enterohepatic cycles of bile acids can be calculated by 4-6. Patients with cholesterol gallstones maintain normal bile acid output by enhanced cycling of the small pool: An average of 50% of the pool passed the duodenum per hour. A decreased bile acid pool is also present in cases of advanced cirrhosis of the liver. However, hourly output of bile acids in these patients is significantly less than in mild cirrhosis (with normal bile acid pool) or normal controls. Therefore the hourly fraction of the pool secreted is similar to healthy subjects. These findings provide an important information to explain abnormalities in bile acid metabolism in cirrhosis.
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PMID:[Simultaneous determination of gastric emptying and bile and pancreatic enzyme secretion]. 106 80

Somatostatin 28 (S-28), originating in gastrointestinal cells, is secreted into the circulation and increases in humans after ingestion of a mixed meal. To evaluate the possibility that the increased levels of S-28 post cibum might modulate the release of enzymes and bicarbonate from the exocrine pancreas, S-28 was infused intravenously into healthy volunteers to levels seen after food intake. During S-28 infusion, the output of lipase, trypsin, amylase, and bicarbonate stimulated by either exogenous cholecystokinin octapeptide or endogenous signals from intraduodenal administration of tryptophan or a mixture of amino acids was significantly reduced. It is concluded that S-28 released from the gut during food intake modulates pancreatic exocrine function in humans.
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PMID:Evidence for hormonal inhibition of exocrine pancreatic function by somatostatin 28 in humans. 135 58

When the gene for the mosquitocidal protein CryIVA was expressed in two strains of Bacillus thuringiensis (Bt) cured of their resident delta-endotoxin genes, the protein accumulated as large inclusions. The inclusions produced in the Bt subsp. kurstaki recipient strain were twice as soluble at alkaline pH as the inclusions produced in Bt subsp. israelensis. Solubilized protoxins were activated by treatment with mosquito gut extracts or trypsin for varying lengths of time and tested for in vitro cytotoxicity on cell lines of three genera of mosquito. CryIVA treated with any of the mosquito gut extracts for 6 h showed significant toxicity against Anopheles gambiae cells and slight activity on Culex quinquefasciatus cells. For CryIVB, the only significant cytotoxicity observed was against Aedes aegypti cells after treatment with Aedes gut extract. In in vivo bioassays, both CryIVA, purified from either of the Bt recipient strains, and CryIVB inclusions were similarly toxic to A. aegypti and A. gambiae larvae but CryIVA was 25-fold more toxic to C. quinquefasciatus. Synergism in vivo between the two toxins was revealed when results from assaying single toxins and mixtures were compared. Mixtures of CryIVA and CryIVB proved to be 5-fold more toxic to Culex than either toxin used singly and showed a reduced but similar synergism when tested against Aedes and Anopheles larvae. The synergism was not duplicated in vitro using cell lines from these three insects.
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PMID:Comparison of Bacillus thuringiensis subsp. israelensis CryIVA and CryIVB cloned toxins reveals synergism in vivo. 135 48

The specificity and properties of a novel IgA receptor expressed on the surface of a tissue culture-adapted B cell lymphoma, T560, that originated in murine gut-associated lymphoid tissue, have been explored. Like the IgA receptors of murine T and splenic B cells studied by others, the T560 IgA receptor is trypsin sensitive and neuraminidase resistant and is up-regulated on T560 cells by exposing them overnight to high concentrations of polymeric IgA. Unlike them, the T560 IgA receptor is inhibited by low concentrations of IgM and high concentrations of IgG2a and IgG2b, binds at pH 4.0 but not at pH 8.0, is down-regulated by activation of protein kinase C and is sensitive to phosphatidylinositol-specific phospholipase C, indicating that it is glycosyl phosphatidylinositol-linked to the cell membrane. It is not a cell-bound form of galactosyl transferase, does not appear to bind to Ig through carbohydrate residues and does not react specifically with antibody to secretory component. It may be a completely new, cross-reactive receptor, perhaps related in some way to the polymeric Ig receptor or to the receptor for IgA expressed on the apical surface of Peyer's patch M cells, which is known to cross-react with IgG. Alternatively, it may be homologous to the highly IgA-specific Fc alpha R of T cells but, perhaps because of its glycosyl phosphatidylinositol linker, may have an ability to move and interact with other Ig receptors on the cell surface such that Ig bound to them are cross-inhibitory.
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PMID:A novel IgA receptor expressed on a murine B cell lymphoma. 137 46

Changes in the activities of three gastric and nine pancreatic enzymes plus colipase were determined during postnatal development and weaning in calves. In calves exclusively milk-fed for 2, 7, 28, 56, 70 and 119 d, the enzyme activities per kilogram of empty live weight increased with age for chymotrypsin, elastase, carboxypeptidases A and B, ribonuclease and alpha-amylase, decreased for chymosin, lysozyme and colipase but showed no change in the case of pepsin, trypsin, lipase and phospholipase A2 compared with animals at birth. The greatest increase was that in alpha-amylase activity (about 50-fold between d 2 and 119). In calves weaned between d 28 and 56, all the activities were higher than in milk-fed animals, except that of chymosin (which was slightly lower) and that of colipase (which did not change). At 119 d of age, chymotrypsin, carboxypeptidase A, alpha-amylase and lipase were 1.6- to fourfold higher in ruminants than in preruminants. Thus, most enzyme activities were modified first by colostrum and milk intake, and again upon weaning by development of the forestomachs and ingestion of solid food. These ontogenic patterns might be under the control of many gut regulatory peptides, the plasma concentrations of which changed simultaneously. Some gastric and pancreatic enzymes were correlated to plasma concentrations of these gut regulatory peptides.
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PMID:Gastric and pancreatic enzyme activities and their relationship with some gut regulatory peptides during postnatal development and weaning in calves. 137 46

We studied the effect of short-term (3 h) pancreatic duct obstruction (PDO) on the exocrine pancreas and on the secretion of lysosomal enzymes into the pancreatic juice of rabbits during stimulation by pancreatic secretagogues. The following evaluations were made: serum amylase levels, pancreatic water content, pancreatic amylase, trypsinogen and cathepsin B content, and output of pancreatic enzymes and lysosomal hydrolases when stimulated by secretin and caerulein as well as the distribution of cathepsin B in subcellular fraction. Cellular fragility (LDH leakage from dispersed acini) and subcellular organellar fragility (cathepsin B leakage from lysosomes and malate dehydrogenase leakage from mitochondria) were also evaluated. PDO for 3 h plus secretin infusion caused a significant rise in serum amylase levels, pancreatic water content, and pancreatic amylase and trypsinogen content due to congestion of digestive enzymes during PDO. There was also a redistribution of cathepsin B from the lysosomal fraction to the zymogen fraction and increased cellular and subcellular organellar fragility. In normal rabbits and in those with only secretin infusion, caerulein stimulated the secretion of cathepsin B into pancreatic juice. Just after PDO, the secretion of cathepsin B, amylase and trypsinogen significantly decreased. By 24 h after PDO, the output of cathepsin B stimulated by caerulein and secretin had increased significantly. Amylase and trypsinogen output were also significantly increased at this stage, in both the secretin and caerulein fractions. These results indicate that the secretion of lysosomal enzymes into pancreatic juice is stimulated by gut hormones, such as caerulein, in the normal physiological state and in pathological states, such as PDO. These results also show an important role of increased cellular and subcellular organellar fragility in the pathogenesis of pancreatic injuries induced by PDO and augmented secretion of both lysosomal enzymes and pancreatic digestive enzymes in the recovery stage after PDO and their important roles at this stage. Lysosome enzymes also seem to play some physiological roles in the pancreatic ductal system in normal physiological states as well as their roles in pathological states, because cathepsin B can activate trypsinogen, and trypsin can activate many other enzymes.
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PMID:Effect of short-termed pancreatic duct obstruction on the pancreatic subcellular organellar fragility and pancreatic lysosomal enzyme secretion in rabbits. 138 8

Fusion genes combining the 5'-transcriptional regulatory region of the rat trypsin I gene and the structural gene of human growth hormone as a reporter were expressed to the high levels characteristic of the endogenous trypsin I gene selectively in the acinar cells of the pancreas of transgenic mice. As little as 232 base pairs of trypsin gene sequences containing the transcriptional start site and upstream promoter elements were sufficient to direct pancreatic expression. The tissue-specific expression was controlled transcriptionally. Trypsin-human growth hormone fusion transgenes also were expressed, although at low levels, in the stomach, an unexpected site for the expression of pancreatic digestive enzymes. Expression in the stomach of endogenous trypsin, elastase, and amylase genes in both normal and transgenic mice verified that transgene expression was consistent with normal expression of pancreatic genes. Endogenous amylase colocalizes with pepsinogen in the acinar cell-like Chief cells of the glandular portion of the mouse stomach. The expression of pancreatic genes in stomach cells is probably the consequence of similar developmental origins of pancreatic and gastric acinar cells from the primordial gut.
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PMID:Selective expression of trypsin fusion genes in acinar cells of the pancreas and stomach of transgenic mice. 146 18


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