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:3.1.3.1 (alkaline phosphatase)
47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sections of hypernephroid carcinoma from 20 cases were investigated for aldolase isozymes A and B by a mixed aggregation immuno-cytochemical technique, and for the brush border membrane enzymes aminopeptidase and alkaline phosphatase by conventional histochemical techniques. It was found that the cases could be grouped into four types: type 1 (1 case) contained all 4 enzymes; type 2 (7 cases) contained all enzymes except aldolase-B; type 3 (7 cases) possessed aldolase-A and one brush border membrane enzyme; type 4 (5 cases) contained only aldolase-A. The aldolase-A concentration in all tumor cells was higher than that in proximal tubule cells, whereas the concentration of the two brush border enzymes was lower. In cases tydolase-B and/or higher amounts of the brush border enzymes than the surrounding cells. No correlation was observed between clear cell and granular cell hypernephroid carcinomas or the invasiveness or the nuclear polymorphism of the tumors on the one hand with their enzyme type on the other. These histological enzyme analyses suggest that most, if not all, hypernephroid carcinomas are derived from kidney proximal tubule cells and that the tumor cells then progressively lose aldolase-B, and subsequently the brush border enzymes, but at the same time producing more aldolase-A. The presence of the enzyme-rich patches suggest different patterns of proliferation and differentiation among the tumor cell population. Three tumors other than hypernephroid carcinoma were also examined in this way. The results suggest that histoenzymological analyses are of general applicability in studies of tumor progression. They should also be useful for biopsy and aspiration cytology.
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PMID:A classification of tumor development based on an analysis of enzymes in tissue sections of hypernephroid carcinoma in man. 101 98

Duodenal brush border membrane proteins were studied in chicks at different developmental stages. The protein pattern obtained from polyacrylamide gels with 2-day-old chick preparations was distinctly different from that obtained with 20-day embryos. The most remarkable changes were seen in the region of a protein with an Rf of 0.25, an area with high sucrase and maltase maltase activity, and in the region of a protein with an Rf of 0.28, which was characterized by alkaline phosphatase activity. These proteins reacted strongly with carbohydrate stain after hatching.
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PMID:Proteins of chick duodenal brush borders during developmental changes. 102 55

Activities of the small intestinal mucosal enzymes lactase, sucrase, maltase, alkaline phosphatase and N-acetyl-beta-glucosaminidase were studied in rats with surgically-induced upper intestinal stasis and in control animals. The first four are brush border enzymes, the latter a lysosomal enzyme. There was a reduction in the activities of all enzymes in the operated animals. The change lining was significant and most marked in mucosa the blind loop and gut distal to it; areas in which there is gross bacterial overgrowth and excessive levels of intraluminal deconjugated bile salts. The significance of these findings in relation to malabsorption consequent on bacterial contamination of the upper gut is uncertain and requires further study.
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PMID:Effect of stasis on intestinal enzyme activities. 105 24

Digestive enzymatic activities (disaccharidases, alkaline phosphatase, peptide hydrolases) have been determined in the mucosa of 14 patients with chronic pancreatitis. All had an abnormal secretin-pancreozymin test. Four patients had insulin-dependent diabetes mellitus, four a pathological glucose tolerance test. Nine patients had steatorrhoea. Maltase, sucrase, and alkaline phosphatase activity was significantly elevated in patients with exocrine pancreatic insufficiency, whereas those of lactase, trehalase, and peptide hydrolase were normal. Patients with steatorrhoea had higher maltase and sucrase activity than those without steatorrhoea, whereas decreased glucose tolerance had no effect on brush border enzymatic activity. It is suggested thatdecreased exocrine rather than decreased endocrine pancreatic function is responsible for the increase in intestinal disaccharidase and alkaline phosphatase activity, possible by the influence of pacreatic enzymes on the turnover of brush border enzymes from the luminal side of the mucosal membranes or by direct hormonal stimulation though cholecystokinin.
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PMID:Influence of exocrine and endocrine pancreatic function on intestinal brush border enaymatic activities. 109 2

About 90% of the protein of hamster intestinal brush borders was solubilised in 0.25% (w/v) sodium dodecyl sulphate without total loss of biological activity. Detergent-polyacrylamide gel electrophoresis of the solubilised proteins separated 10-15 bands and partially resolved maltase, lactase, sucrase-maltase, trehalase and alkaline phosphatase activities. The disaccharidases, which were associated with the higher molecular weight proteins, were preferentially solubilised with 0.1%. (w/v) Triton X-100, butanol or papain, whereas Tris and NaI extracted only the lower molecular weight proteins, possible derived from the core filaments. Electrophoresis of brush border proteins metabolically labelled with [14-C] glucosamine suggested that many of the membrane-bound enzymes are glycoproteins. However, chromatography of a papain digest on Sephadex G-200 showed that the sucrase-maltase complex can be separated nearly free of carbohydrate without total loss of activity. The importance of characterizing membrane proteins solubilised by a number of techniques is discussed.
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PMID:Solubilization of brush borders of hamster small intestine and fractionation of some of the components. 113 70

Feeding sodium deoxycholate orally to rats for four days caused depression of the activity of the small intestinal enzymes lactase, sucrase, maltase, alkaline phosphatase, and N-acetyl-beta-glucosaminidase. The first four are brush border enzymes, the last a lysosomal enzyme. Alkaline phosphatase activity recovered very rapidly and rebounded to above the normal level within 24 hours. The activity of the three disaccharidases returned to normal within seven days while no recovery was observed within 96 hours of the activity of the lysosomal enzyme, N-acetyl-beta-glucosaminidase, after removing the bile salt from the diet.
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PMID:Deoxycholate depresses small-intestinal enzyme activity. 114 Jun 27

1. Intestinal brush border enzymes have heterogeneous rates of turnover, the largest proteins having the fastest turnover. Since the membrane faces the intestinal lumen, the effects of pancreatic factors were examined in mediating this turnover. Surgical subtotal pancreatectomy was used as an experimental model to study the turnover of brush border proteins in the absence of most pancreatic secretions. 2. Subtotal (95%) pancreatectomy of rats was found to cause elevations by about 50% of total activity and specific activities of certain brush border enzymes (maltase, sucrase, lactase), but not of others (alkaline phosphatase, trehalase). Rats were judged to be functionally deficient in pancreatic proteolytic enzymes (a) by demonstration of vitamin B-12 malabsorption, which was corrected by trypsin, and (b) by the finding of only about 20% of proteolytic activity appearing in the lumen after a test meal when compared to control. 3. To measure protein turnover in vivo the method of double labelling was used, where [3H]- and [14C]valine were administered intraduodenally in sequence 10 h apart. With this technique, a high 3H/14C ratio is correlated with rapid turnover. Proteins with apparent molecular weights of about 200 000-270 000 were found to turn over more rapidly than smaller proteins. 3H/14C ranged from 4.7 to 6.2 in animals without pancreatic insufficiency. In the face of decreased pancreatic proteolysis, the 3H/14C ratio was 2.3-3.1, similar to that of proteins with a slow half life. 4. Estimates of relative synthetic rates of large brush border proteins were lower than normal in pancreatectomized animals, but were constant over the period of the labelling experiment. The high enzyme levels in the face of lower synthetic rates confirms that, at the new steady rate, degradation rates must be slower for large brush border proteins in pancreatic insufficiency. 5. In vitro, using purified brush borders, unfractionated pancreatic enzymes were found to remove sucrase, maltase and lactase, but not alkaline phosphatase and trehalase. The enzyme most potent in this respect was the pancreatic protease, elastase. Non-proteolytic enzymes (amylase, lipase, phospholipase A) were inactive in removing enzyme from the brush border. The addition of elastase to pancreatectomized animals in vivo restored the rapid turnover rate of large brush border proteins. 6. A model is thus proposed for the normal catabolism of some large intestinal brush border proteins. It is suggested that the surface of intestinal absorptive cells is being constantly remodelled, and that certain surface enzymes are in part removed from the membrane by the action of pancreatic proteases. A possible special role for elastase is suggested.
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PMID:The possible role of pancreatic proteases in the turnover of intestinal brush border proteins. 114 88

The releases of proteins, maltase, lactase, sucrase, trehalase, alkaline phosphatase, gamma-glutamyltransferase and leucylnaphthylamide-hydrolyzing activity from human intestinal brush bborder membrane vesicles by various enzymes (especially pancreatic proteases) have been studied. The brush border membrane enzymes are not solubilized by digestion with trypsin and chymotrypsin but are largely released after treatment with papain or elastase. Most of the enzymes are fully active after the proteolytic treatment. All proteins released by papain and elastase have been identified by electrophoresis to already known intestinal hydrolases. Electron microscopy of brush border membrane vesicles demonstrates "knob-like" structures (particles) attached to the external side of the membrane. During papain treatment, enzyme removal runs parallel with the disappearance of the particles. During elastase treatment it is not possible to correlate the release of the enzymic activities with the removal of the particles. The results indicate that most of the intestinal hydrolases are surface components attached to the external side of the membrane. They are in accord with the concept that the brush border membrane enzymes are organized within the membrane in a mosaic-like pattern.
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PMID:Enzymic solubilization of the human intestinal brush border membrane enzymes. 127 90

Renal epithelial function, proton flux and sodium stimulated proton flux, was observed in vesicles isolated from the brush border of the proximal tubule of Sockeye Salmon (Oncorhynchus nerka) during migration. Brush border membrane vesicles (BBMV) were isolated from the body kidney of Sockeye Salmon using aggregation/differential centrifugation techniques. Vesicle purity was tested using a series of epithelial and basal lateral markers including alkaline phosphatase, maltase, gamma-glutamyl transferase (GGTP), Mg(2+)-activated ATP-ase, Na(+)+K(+)-activated ATPase, and 5'-nucleotidase and the lysosomal marker acid phosphatase. An enrichment/depletion factor for each marker was determined by comparison of purified BBMV with kidney homogenate. Vesicles exhibit an enrichment factor for alkaline phosphatase, GGTP, maltase, Mg(2+)-activated ATP-ase, Na(+)+K(+)-activated ATPase, and 5'-nucleotidase. A depletion factor was observed for acid phosphatase. Vesicle integrity was tested by measuring the time course of proton flux in the presence of a pH gradient. Amiloride sensitive sodium stimulated proton flux was observed in these vesicles. The presence of sodium caused a saturable increase in the rate of proton flux, indicating the activity of a sodium/proton antiport protein in BBMV.
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PMID:Proton transport and Na+/H+ exchange in vesicles isolated from sockeye salmon (Oncorhynchus nerka) kidneys during migration from salt to fresh water. 132 4

The Golgi apparatus and alkaline and acid phosphatase and nonspecific esterase activities were studied in the jejunal epithelium of adult male albino mice (Mus musculus) under normal conditions and after MTX treatment. In the control, the Golgi apparatus took the form of rods, spheres and crescents occupying the supranuclear region. After MTX, the Golgi apparatus, in most of the cells, was hypertrophied. In the control cells, alkaline and acid phosphatase and nonspecific esterase activities were moderate and localized supranuclearly, but were intense in the brush border and basement membrane. After MTX, all three enzyme activities increased, with a marked reaction in the brush border and basement membrane. The increase in alkaline phosphatase may mean that more phosphate transport is needed in the active phosphorylation process or in the transfer of MTX macromolecules across the cell membrane, or it may be due to MTX-induced disorganization of metabolism. The increase in acid phosphatase activity denotes an increase in catabolic processes resulting from imbalance of lysosomal function, while the rise in nonspecific esterase activity could be related to fatty acid metabolism, or it might be due to the detoxicant function of esterases. In all control and MTX-treated specimens, the supranuclear concentration of these enzymes coincided with the localization of the Golgi apparatus.
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PMID:The effect of methotrexate (MTX) on the small intestine of the mouse. IV. The Golgi apparatus, phosphatases and esterases. 133 5


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