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)

The distribution of alkaline phosphatase was investigated in corneas of various animals by means of histochemical and biochemical methods. Special attention was paid to keratocytes that proved to be positive when a proper substrate and technique were used even if the activity differed according to animal species. Naphthol-AS-MX-phosphatate with Variamine-Blue-RT salt in the simultaneous azocoupling method was the most sensitive substrate; less suitable were naphthol-AS-phosphate, and particularly l-naphthyl-phosphate with Fast-Blue-BB-salt in the same method. Keratocytes were completely negative with beta-glycerophosphate in the Gomori technique. Contrary to keratocytes, epithelial and endothelial cells were without substrate predilection. The results of both approaches showed a wide inter-species variability. The overall activity of alkaline phosphatase detected histochemically and its activity in the unsedimentable fraction of whole corneas determined biochemically was in good agreement. The highest activity was found in the calf cornea; enzyme levels decreased gradually in the bovine, rabbit, dog, sheep, and pig cornea.
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PMID:A study on alkaline phosphatase in cornea of various animals with special regard to keratocytes. 30 21

Since dietary calcium had been reported to reduce plasma lipids, the effects of calcium carbonate (CaCO3, 2 g/day) and the calcium salt of p-chlorphenozyisobutyrate (Ca-CPIB, 2 g/day), both singly and in combination, were studied in outpatients with primary hyperlipidaemia. Three groups of five patients were followed in a double-blind cross-over study, in which placebo and the drugs were given alternately during four-week periods. The main results were: 1) CaCO3 alone did not produce any significant changes in plasma lipids. 2) Ca-CPIB reduced LDL-cholesterol in patients with type IIa and IIb by an average of 29 and 21%, respectively. It also lowered VLDL-triglyceride by 50% in type IIb and by 48% in four out of five patients with type IV. 3) The combination of CaCO3 and Ca-CPIB reduced LDL-cholesterol by 31 and 25% in types IIa and IIb, respectively. It also lowered VLDL-triglyceride by 48-52% in types IIa and by 46% in four out of five patients with type IIb. 4) Three out of five patients with type IV had a rise of LDL-cholesterol while on Ca-CPIB alone; two of the patients had the rise while on the combination. 5) After treatment with Ca-CPIB, either singly or in combination, there was a statistically significant lowering of ESR and of plasma inorganic phosphate and alkaline phosphatase. No clinical side effects were noted.
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PMID:Effect of calcium p-chlorphenoxyisobutyrate and calcium carbonate on plasma lipids and lipoproteins of patients with hyperlipoproteinaemia. 35 20

Using fresh frozen, freeze-dried or cryostate sections from aldehyde fixed rat tissues 13 diazonium salts were tested as simultaneous coupling reagents for the localization of acid, neutral and alkaline hydrolases with azo indoxyl methods. Hexazotized new fuchsine and/or Fast blue B are the diazonium salts of choice for the demonstration of acid beta-galactosidase, neuraminidase, beta-N-acetylglucosaminidase, acid phosphatase, and non-specific esterase followed by hexazotized p-rosaniline. Fast blue VB, BB and RR and Fast violet B are recommended for the investigation of alkaline phosphatase and lactase, Fast garnet GBC for acid beta-galactosidase, glucosaminidase and lactase. Fast red B, RC, RL and TR and Fast black K can only be employed for lactase studies. The exact concentration of the coupling reagent depends on the activity of the enzyme and the organ imvestigated. On the average 0.01-0.02 ml unstable diazonium salt/ml and 0.3--1 microgram stable diazonium salt/ml are sufficient for the correct localization of these hydrolases. Freeze-dried cryostat sections yield the best results in the demonstration of lactase and alkaline phosphatase independent on the coupling reagent used. Sections from formaldehyde or glutaraldehyde fixed organs are superior for the localization of the other hydrolases; an exception is the investigation of acid beta-galactosidase and glucosaminidase with Fast garnet GBC. Then, excellent results are obtained also with freeze-dried material. Fresh frozen sections are suitable for the localization of lactase with hexazotized new fuchsine or p-rosaniline and of alkaline phosphatase with Fast blue VB and BB or violet B. The total activity of acid, neutral and alkaline hydrolases can be investigated using semipermeable membranes in combination with all unstable and stable diazonium salts of choice. Reliable osmification of the azoindoxyl dye is only possible if hexazotized p-rosaniline is employed for coupling; without further posttreatment all azoindoxyl dyes are extracted by ethanol, isopropanol or xylol. 7 incubation media are given for the demonstration of hydrolases with azoindoxyl methods at the level of light microscopy for routine studies and typical examples for the application of these methods are presented. A modified procedure is described for the freeze-drying of cryostat sections with the Edwards-Pearse tissue dryer EPD3.
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PMID:[Azoindoxyl methods for the investigation of hydrolases. IV. Suitability of various diazonium salts (author's transl)]. 36 63

The effect of intestinal bacterial over-growth on brush border hydrolases and brush border glycoproteins was studied in nonoperated control rats, control rats with surgically introduced jejunal self-emptying blind loops, and rats with surgically introduced jejunal self-filling blind loops. Data were analyzed from blind loop segments, segments above and below the blind loops, and three corresponding segments in the nonoperated controls. Rats with self-filling blind loops had significantly greater fat excretion than controls and exhibited significantly lower conjugated:free bile salt ratios in all three segments. Maltase, sucrase, and lactase activities were significantly reduced in homogenates and isolated brush borders from the self-filling blind loop, but alkaline phosphatase was not affected. The relative degradation rate of homogenate and brush border glycoproteins was assessed by a double-isotope technique involving the injection of d-[6-(3)H]glucosamine 3 h and d-[U-(14)C]glucosamine 19 h before sacrifice, and recorded as a (3)H:(14)C ratio. The relative degradation rate in both homogenate and brush border fractions was significantly greater in most segments from rats with self-filling blind loops. In the upper and blind loop segments from rats with self-filling blind loops, the (3)H:(14)C ratios were higher in the brush border membrane than in the corresponding homogenates, indicating that the increased rates of degradation primarily involve membrane glycoproteins. Incorporation of d-[6-(3)H]glucosamine by brush border glycoproteins was not reduced in rats with self-filling blind loops, suggesting that glycoprotein synthesis was not affected. Polyacrylamide gel electrophoresis of brush border glycoproteins from the contaminated segments indicated that the large molecular weight glycoproteins, which include many of the surface hydrolases, were degraded most rapidly. Brush border maltase, isolated by immunoprecipitation, had (3)H:(14)C ratios characteristic of the most rapidly degraded glycoproteins. The results indicate that bacteria enhance the destruction of intestinal surface glycoproteins including disaccharidases. Since alkaline phosphatase, a glycoprotein, is not affected, the destruction is selective and presumably involves only the most exposed membrane components.
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PMID:Pathogenesis of mucosal injury in the blind loop syndrome. Brush border enzyme activity and glycoprotein degradation. 41 Aug 30

For the purpose of detecting the synthesis of zinc metalloenzymes after zinc supplementation in an experiment using rats the animals were first depleted for 15 days and subsequently injected a labelled zinc salt solution (65Zn-ZnCl2) in a dosis of 0.4 mg (in terms of Zn) and with an activity of 3.0 muCi/100microliter. After a 5-day depletion period, the activity of the metallo-enzymes alkaline phosphatase in plasma and in the femur and carboxy-peptidase A and B in the pancreatic gland was found to rise at the same rate as the 65Zn-measuring rate in plasma, femur and pancreatic gland. By calculating correlations this interdependence was demonstrated. Thus the highly significant correlation coefficients prove for these metalloenzymes that a synthesis with the injected zinc salt has taken place whilst for carbo-anhydrase in blood this evidence was not furnished. As the zinc dosis is not exclusively used for the enzyme synthesis, but additional 65Zn is incorporated into the individual organs, it does not appear to be possible to draw conclusions from the 65 Zn-measuring rate in the individual organs on the intermediary availability.
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PMID:[Demonstration of zinc-metalloenzyme syntheses after zinc supplements for deficient animals by means of measurement of the incorporation of 65Zn in various organs]. 41 27

The molecular weight of a partially purified alkaline phosphatase (orthophosphoric-monoester phosphohydrolase, EC 3.1.3.1) from the halotolerant yeast Debaryomyces hansenii was estimated to 110,000 by gel filtration. The isoelectric point determined by electrofocusing was at approximately pH 4.4. The enzyme had a broad specificity against phosphomonoesters and also attacked some acid anhydrides. Arsenate, molybdate, and orthophosphate acted as competitive inhibitors. Various metal-binding agents inhibited enzyme activity. A zinc addition almost completely reversed the EDTA inhibition. Magnesium stimulated enzyme activity and was required for maintenance of activity at high concentrations of Na+. Increasing glycerol concentration increased the value of the Michaelis constant (Km) and decreased the maximum velocity (V). Solutions equimolar in KCl and NaCl stimulated enzyme activity by increasing V, whereas the Km was almost unaffected by salt concentration. Enzyme extracted from cells cultured at low salinity was indistinguishable from that of cells grown in the presence of 2.7 M NaCl with respect to several criteria.
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PMID:Properties of alkaline phosphatase of the halotolerant yeast Debaryomyces hansenii. 41 79

The overall transport of bile salts across the hepatocyte is characterized as a carrier-mediated process whose rate-limiting step is biliary secretion. Specific bile salt binding proteins have been identified in liver surface membrane fractions and were postulated to represent the initial interaction in bile salt translocation across both the sinusoidal and canalicular membranes. To test this hypothesis, cycloheximide was administered to rats to inhibit hepatic protein synthesis. 16 h after cycloheximide administration [14C]leucine incorporation into hepatic protein was inhibited by 93% at 1 h and 47% at 12 h. However, values of liver function tests were not increased, although serum albumin, serum alanine amino-transferase, and alkaline phosphatase were significantly decreased. Light and electron microscopy did not demonstrate necrosis or fat accumulation. The latter demonstrated minimal disorganization of rough endoplasmic reticulum and occasional lamellar whorls. 16 h after cycloheximide administration bile salt independent bile flow, basal bile salt excretion, and basal bile flow were unaltered, but the maximum bile salt transport capacity was reduced to 62% of control and 24 h later to 38%. Decreased bile salt transport was reversible, for it returned to control values after 48 h, when hepatic protein synthesis was also normal. Maximum bromosulfophthalein (BSP) transport, on the other hand, was reduced after 16 h to only 85% of control. Both bile salt and BPS maximum transport capacities decreased with time during inhibition of protein synthesis, apparently following first order kinetics. It was estimated that their half-lives are 20 h for bile salt transport and 55 h for BSP transport. These different turnover rates suggest that cycloheximide does not decrease active transport through generalized hepatic dysfunction or alteration of high energy sources possibly required for transport. The maximum number of [14C]cholic acid binding sites in liver surface membrane fractions was determined by an ultrafiltration assay. They were reduced to 68% of control after 16 h of cycloheximide and to 25% after 24 h. This reduction in the number of binding sites is apparently selective, for the activities of the liver surface membrane enzymes (Na+-K+)ATPase, Mg++-ATPase, and 5'-nucleotidase were not significantly changed. The associated alterations in bile salt transport and the maximum number of binding sites after cycloheximide administration suggests that these receptors may be the bile salt carriers.
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PMID:Regulation of hepatic transport of bile salt. Effect of protein synthesis inhibition on excretion of bile salts and their binding to liver surface membrane fractions. 43 30

The observation of a non-metastatic reactive hepatopathy associated with a hypernephroma in a 39-year-old man who had had fever for 4 months led to a review of the literature and an analysis of basically three aspects of the disorder: a) The various manifestations of carcinoma of the kidney, which include a large number of paraneoplastic clinical symptoms (polycythemia, anemia, prolonged fever, hypercalcemia, hypertension, nefropathy, loss of salt, peripheral neuropathy, and amyloidosis); b) an alteracion of hepatic function known since 1961 which is characterized by an abnormal retention of sulfobromophthalein, increase of alkaline phosphatase, prothrombin decrease, dysproteinemia with hypoalbuminemia, and alpha2-globulin increase. It may or may not be accompanied by enlargement of the liver. c) Criteria of operability of the primary tumor.
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PMID:[Liver disease associated with hypernephroma. A case report (author's transl)]. 45 99

The effect of anions on the thermodynamic activation functions for a model enzyme, calf intestinal alkaline phosphatase (EC 3.1.3.1), have been studied in order to examine the role of protein hydration changes in establishing the energetics of enzyme catalysis. The influences of these anions on the activation volume (delta V) and activation free energy (delta G) reflected clear Hofmeister (lyotropic) series effects, in the order F- greater than Cl- greater than Br- greater than I- (order of increasing salting-out potential). A pronounced covariation was observed between the influences of these anions on Vmax, which is proportional to delta G, and on the negative activation volume of the reaction. Fluoride was able to counteract the influences of Br- and I- on both Vmax and delta V when combinations of these anions were employed. The effects of Br- and I- on Vmax and delta V were more pronounced at lower temperatures. The control delta V was increasingly negative at reduced temperatures. The effects of the neutral salts and propanol on delta V and delta G, as well as the effects of salting-in anions on the activation enthalpy and the negative activation entropy of the reaction, are consistent with a model which proposes that peptide groups or polar side chains on the native enzyme exergonically increase their exposure to solvent during the catalytic activation event. These conclusions are in accord with the known free energy, enthalpy, entropy, and volume changes which occur when model peptide groups are transferred between water and concentrated salt solutions. Consistent with the kinetic results, the fluorescence emission wavelength maximum of alkaline phosphatase increased in the presence of anions in the order F- greater than Cl- greater than Br- greater than I-. The salting-out ion (F-) and the salting-in ions (Br- and I-) shifted lambda max in different directions, and these lambda max shifts could be counterbalanced by using equimolar combinations of salting-in and salting-out anions. Control experiments with a model compound, N-acetyltryptophanamide, showed that the spectra shifts caused by the salts did not result solely from differential quenching by the anions of the solvent-exposed tryptophan(s) on the enzyme. Hofmeister additivity phenomena indicated that the solvent is at the basis of these salt-induced enzyme structural changes. It is concluded that changes in protein solvation during enzymic reactions contribute significantly to the thermodynamic activation parameters in both the native and the salt-perturbed enzyme.
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PMID:Effects of anions on the activation thermodynamics and fluorescence emission spectrum of alkaline phosphatase: evidence for enzyme hydration changes during catalysis. 51 38

Purified phosphatidylinositol-specific phospholipase C from Staphylococcus aureus released a substantial proportion of the total alkaline phosphatase activity from a wide range of tissues from several mammalian species. Co-purification of the phospholipase C and alkaline phosphatase-releasing activities and the inhibition of both these activities by iso-osmotic salt solutions suggested that the releasing effect was unlikely to be due to a contaminant.
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PMID:Release of alkaline phosphatase from membranes by a phosphatidylinositol-specific phospholipase C. 58 58


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