scholarly journals Adaptive increase in phytate digestibility by phosphorus-deprived rats and the relationship of intestinal phytase (EC 3.1.3.8) and alkaline phosphatase (EC 3.1.3.1) to phytate utilization

1983 ◽  
Vol 49 (1) ◽  
pp. 145-152 ◽  
Author(s):  
Robert J. Moore ◽  
Trygve L. Veum
Keyword(s):  
Alkaline Phosphatase ◽  
Inositol Phosphates ◽  
Enzymic Hydrolysis ◽  
Intestinal Alkaline Phosphatase ◽  
Alkaline Phytase ◽  
Treatment Groups ◽  
Phosphorus Deprivation ◽  
Relationship Of ◽  
The Relationship ◽  
Hydrolysis Of

1. The effects of phosphorus deprivation on phytate digestibility, phosphorus utilization and intestinal phytase (EC3.1.3.8) and alkaline phosphatase (EC3.1.3.1) in rats were investigated.2. P deprivation was achieved by giving rats a diet containing 3 g P/kg and resulted in hypophosphataemia, hypercalcaemia, hypercalciuria, and lower levels of P absorbed and retained, and calcium retained.3. Rats adapted to P deprivation by increasing the digestion of total dietary-P and phytate-P.4. Levels of intestinal alkaline phosphatase and alkaline phytase were not different between the two treatment groups.5. P deprivation in the rats given the marginal-P diet may be a result of a lower absorption of total dietary-P or increased absorption of inositol phosphates formed during the enzymic hydrolysis of phytate which are not readily utilized by the rat.6. These results suggest that intestinal phytase and alkaline phosphatase do not play a role in the adaptive increase in phytate digestibility by rats given marginal-P diets. The adaptation may result from enhanced phytase or alkaline phosphatase synthesis by the gastrointestinal microflora stimulated by a lower level of P in the digesta.

Influence of dietary phosphorus and sulphaguanidine levels on P utilization in rats

1984 ◽  
Vol 51 (3) ◽  
pp. 453-465 ◽  
Author(s):  
Robert J. Moore ◽  
Philip G. Reeves ◽  
Trygve L. Veum
Keyword(s):  
Alkaline Phosphatase ◽  
Intestinal Mucosa ◽  
Inositol Phosphates ◽  
Female Rats ◽  
Alkaline Phytase ◽  
Dietary Phosphorus ◽  
Male And Female Rats ◽  
P Utilization ◽  
Hydrolysis Of

1. The effects of dietary phosphorus and sulphaguanidine levels, and sex differences on: (a) phytate digestibility, (b) calcium and P utilization, (c) the activities of alkaline phosphatase (EC3.1.3.1), alkaline phytase (EC3.1.3.8) and acid phosphatase (EC3.1.3.2) in the intestinal mucosa of male and female rats were investigated.2. There was a linear increase in femur ash, Ca and P contents and the maximum force withstood by the fresh femurs as dietary P level was increased from 1.5 to 3.0 to 4.5 g/kg diet.3. The apparent digestibilities of Ca, P and phytate-P decreased as the level of P in the diet increased. Rats given the diets with 1.5 or 3.0 g P/kg were hypercalciuric and hypophosphaturic compared with rats receiving 4.5 g P/kg diet.4. The level of Ca retained was similar for all treatments. The level of P retained increased as the dietary P level increased. This suggests that P deprivation was a result of inadequate amounts of P retained and not due to the absorption of inositol phosphates formed during the enzymic hydrolysis of phytate.5. The addition of sulphaguanidine increased phytate digestibility without changing the activities of acid and alkaline phosphatase or alkaline phytase of the intestinal mucosa. This suggests that these enzymes did not play a role in the increase in phytate digestibility. However, dietary sulphaguanidine enhanced phytate digestibility, suggesting that alterations in the diet which modify either the composition or metabolism of the gastrointestinal microflora may be beneficial in enhancing the in vivo hydrolysis of phytate.6. Differences between males and females are reported and discussed.

scholarly journals Chicken Intestinal Alkaline Phosphatase

1960 ◽  
Vol 43 (6) ◽  
pp. 1149-1169 ◽  
Author(s):  
M. Kunitz
Keyword(s):  
Alkaline Phosphatase ◽  
Zinc Ions ◽  
Magnesium Ions ◽  
Intestinal Alkaline Phosphatase ◽  
Reversible Inactivation ◽  
Higher Temperature ◽  
Kinetics Of ◽  
Hydrolysis Of ◽  
Zn Ions ◽  
Denaturation Of Proteins

Purified chicken intestinal alkaline phosphatase is active at pH 8 to 9, but becomes rapidly inactivated with change of pH to 6 or less. Also, a solution of the inactivated enzyme at pH 4.5 rapidly regains its activity at pH 8. In the range of pH 6 to 8 a solution of purified alkaline phosphatase consists of a mixture of active and inactive enzyme in equilibrium with each other. The rate of inactivation at lower pH and of reactivation at higher pH increases with increase in temperature. Also, the activity at equilibrium in the range of pH 6 to 8 increases with temperature so that a solution equilibrated at higher temperature loses part of its activity on cooling, and vice versa, a rise in temperature shifts the equilibrium toward higher activity. The kinetics of inactivation of the enzyme at lower pH and the reactivation at higher pH is that of a unimolecular reaction. The thermodynamic values for the heat and entropy of the reversible inactivation and reactivation of the enzyme are considerably lower than those observed for the reversible denaturation of proteins. The inactivated enzyme at pH 4 to 6 is rapidly reactivated on addition of Zn ions even at pH 4 to 6. However, zinc ions are unable to replace magnesium ions as cocatalysts for the enzymatic hydrolysis of organic phosphates by alkaline phosphatase.

Survey of Cyclohexylamine Content of Food Products Containing Cyclamates

1970 ◽  
Vol 53 (6) ◽  
pp. 1120-1128
Author(s):  
T Fazio ◽  
J W Howard ◽  
E O Haenni
Keyword(s):  
Weight Control ◽  
Food Product ◽  
Storage Conditions ◽  
Major Type ◽  
Processing And Storage ◽  
Relationship Of ◽  
The Relationship ◽  
And Storage ◽  
Hydrolysis Of ◽  
Content Range

Abstract A national survey was conducted to ascertain the relationship of the cyclohexylamine content of cyclamate-containing products to their composition, processing, and storage conditions. Cyclohexylamine was found in 174 of the 232 samples examined. The cyclohexylamine content range for each major type of food product was as follows: 0.0–8.2 ppm for carbonated beverages; 0.0–5.8 ppm for dry beverage bases; 0.0–1.5 ppm for fruit juices; 0.0–0.8 ppm for weight control foods; and 0.3–66 ppm for food sweetener preparations (liquid and dry base). No correlation between the cyclamate content of products and the cyclohexylamine present was evident. However, the findings indicate that significant hydrolysis of cyclamate can occur.

Patterns of Symptom Distress in Adults Receiving Treatment for Lung Cancer

2002 ◽  
Vol 18 (3) ◽  
pp. 150-159 ◽  
Author(s):  
Mary E. Cooley ◽  
Thomas H. Short ◽  
Helene J. Moriarty
Keyword(s):  
Lung Cancer ◽  
Secondary Analysis ◽  
Symptom Distress ◽  
Course Of Illness ◽  
Lung Cancer Patients ◽  
Treatment Groups ◽  
Relationship Of ◽  
The Relationship ◽  
Over Time

Knowledge of the patterns of symptom distress in adults receiving treatment for lung cancer is an important first step in developing interventions that can potentially lessen symptom distress. The purposes of this secondary analysis were to describe the changes in patterns of symptom distress over time in adults receiving treatment for lung cancer, and to examine the relationship of selected demographic and clinical characteristics to symptom distress. Complete data were available for 117 patients. The patterns of symptom distress in adults receiving treatment for lung cancer varied between treatment groups and over time. Symptom distress scores were moderate to high on entry into the study, indicating that symptom management in newly diagnosed lung cancer patients is essential and should begin early in the course of illness. Moreover, clinical interventions should be tailored to the type of treatment. Various demographic and clinical variables were weak and inconsistent predictors of symptom distress, underscoring the importance of examining the role of psychosocial factors in mediating symptom distress.

THE ROLE OF ALKALINE PHOSPHATASE IN INTESTINAL ABSORPTION I. THE KINETICS OF PHOSPHATASE ACTION ON VARIOUS SUBSTRATES

1953 ◽  
Vol 31 (1) ◽  
pp. 1-7
Author(s):  
Neil B. Madsen ◽  
Jules Tuba
Keyword(s):  
Alkaline Phosphatase ◽  
Average Energy ◽  
Inorganic Phosphorus ◽  
Intestinal Alkaline Phosphatase ◽  
Egg Lecithin ◽  
Michaelis Constants ◽  
Inhibition Studies ◽  
Kinetics Of ◽  
Hydrolysis Of

The kinetics of intestinal alkaline phosphatase action on sodium β-glycerophosphate, glucose 6-phosphate, and egg lecithin have been studied and compared. The Michaelis constants indicate that the enzyme shows considerably less affinity for lecithin than for the other two substrates, and the approximate ratio of activity with lecithin, glucose 6-phosphate, and sodium β-glycerophosphate is 11 : 78.5 : 100. The energies of activation for the hydrolysis of the three substrates do not differ appreciably and the average energy of activation is 14,500 calories per gram-mole. The similarity of the energies of activation together with results from inhibition studies indicate that in all probability the same enzyme is responsible for the release of inorganic phosphorus from each of the three substrates.

scholarly journals Inhibition of the orthophosphatase and pyrophosphatase activities of human alkaline-phosphatase preparations

1967 ◽  
Vol 102 (3) ◽  
pp. 917-921 ◽  
Author(s):  
R.H. Eaton ◽  
D. W. Moss
Keyword(s):  
Alkaline Phosphatase ◽  
Competitive Inhibitor ◽  
Tissue Preparation ◽  
Intestinal Alkaline Phosphatase ◽  
Active Centre ◽  
Low Concentrations ◽  
Type 3 ◽  
Intestinal Preparation ◽  
Hydrolysis Of ◽  
Single Enzyme

1. Inhibition of the pyrophosphatase and orthophosphatase activities of human liver and small-intestinal alkaline-phosphatase preparations by different classes of inhibitors has been studied. 2. Each type of substrate, pyrophosphate or orthophosphate, is a competitive inhibitor of hydrolysis of the other type. 3. l-Phenylalanine is a non-competitive inhibitor of both types of activity of the intestinal preparation, but inhibits neither activity of the liver enzyme. Arsenate is a competitive inhibitor of both activities of both preparations. For a given inhibitor, the values of K(i) are independent of the type of substrate used when measurements are made at the same pH. 4. Mg(2+) ions activate orthophosphatase but inhibit pyrophosphatase, except in very low concentrations. 5. These results are compatible with the presence in each tissue preparation of a single enzyme with one type of active centre, possessing both orthophosphatase and pyrophosphatase activities.

Comparative Analysis of Personality Structures of the Perpetrators of Aggressive and Non-aggressive Offense

2014 ◽  
Vol 6 (3) ◽  
pp. 94-103 ◽  
Author(s):  
A.S. Kalashnikova ◽  
T.G. Vasilenko
Keyword(s):  
Comparative Analysis ◽  
Statistical Analysis ◽  
Structural Analysis ◽  
Qualitative Analysis ◽  
Psychological Characteristics ◽  
Treatment Groups ◽  
Criminal Offenses ◽  
Violent Offenses ◽  
Relationship Of ◽  
The Relationship

The problem of the emergence of aggressive behavior is seen through the analysis of the relationship of proagressive and inhibiting aggression personality structures. The study involved 54 men serving sentences for criminal offenses, of which 24 were accused for violent offenses and 30 - for offenses without resorting to violence. We used questionnaires to study the proagressive and deterring aggression personality structures. Statistical analysis was performed to reveal significant differences between groups and to determine correlations. On this basis, the correlations were interpreted with the help of not only quantitative but also qualitative analysis. The results showed no significant differences in the level of expression of aggression and aggression inhibitors between treatment groups, but we identified qualitative differences in the structural analysis of data from individual psychological characteristics that are expected to distinguish aggressive offenders from the perpetrators without violence.

Low-Km mannose-6-phosphatase as a criterion for microsomal integrity

1998 ◽  
Vol 76 (1) ◽  
pp. 115-124 ◽  
Author(s):  
Bartholomew A Pederson ◽  
James D Foster ◽  
Robert C Nordlie
Keyword(s):  
Endoplasmic Reticulum ◽  
Structural Integrity ◽  
Kinetic Studies ◽  
Reliable Index ◽  
Single Mechanism ◽  
Induced Changes ◽  
Relationship Of ◽  
The Relationship ◽  
Low K ◽  
Hydrolysis Of

The low-Km activity of mannose-6-phosphatase (Man-6-Pase) has been used for many years to measure the structural integrity of microsomes. Recently histone II-A has been shown to activate glucose-6-phosphatase (Glc-6-Pase) and Man-6-Pase activities. However, in contrast to detergents, this compound appears to activate without disrupting microsomal vesicles (J.-F. St-Denis, B. Annabi, H. Khoury, and G. van de Werve. 1995. Biochem. J. 310: 221-224). This suggests that Man-6-Pase latency can be abolished without disrupting microsomal integrity and that even normally microsomes may manifest some low-Km Man-6-Pase activity without being "leaky." We have studied the relationship of Man-6-Pase with microsomal integrity further by measuring the latency of several enzymes reported to reside within the lumen of endoplasmic reticulum. We have also correlated this latency with the microsomal permeability of substrates for these enzymes. We found that (i) lumenal enzymes have different degrees of latency when compared with each other, (ii) permeability, as determined via osmotically induced changes in light scattering, is not always consistent with enzymatic latency, (iii) increases in the hydrolysis of Glc-6-P and Man-6-P were not parallel when microsomes were treated with low but increasing concentrations of detergent, and (iv) kinetic studies suggest that mannose-6-phosphate is hydrolyzed by untreated microsomes by more than a single mechanism. We propose that Man-6-Pase is not a reliable index of the integrity of microsomes.Key words: glucose-6-phosphatase, mannose-6-phosphatase, microsomes, rat liver, intactness.

scholarly journals The influence of metal ions on the orthophosphatase and inorganic pyrophosphatase activities of human alkaline phosphatase

1969 ◽  
Vol 112 (5) ◽  
pp. 699-701 ◽  
Author(s):  
D W Moss
Keyword(s):  
Alkaline Phosphatase ◽  
Metal Ions ◽  
Competitive Inhibitor ◽  
Inorganic Pyrophosphatase ◽  
Intestinal Alkaline Phosphatase ◽  
Alkaline Phosphatases ◽  
Low Concentrations ◽  
Pyrophosphatase Activity ◽  
Hydrolysis Of ◽  
Pyrophosphate Hydrolysis

1. The differential effects of adding Zn2+ and Mg2+ on the orthophosphatase and inorganic pyrophosphatase activities of human intestinal alkaline phosphatase were studied. 2. In the presence of excess of Zn2+, inorganic pyrophosphatase activity is inhibited. At higher concentrations of pyrophosphate, hydrolysis of this substrate takes place, but is inhibited competitively by the Zn2+–pyrophosphate complex. This complex also acts as a competitive inhibitor of orthophosphate hydrolysis. 3. Excess of Mg2+ also inhibits pyrophosphatase action by removal of substrate; at low concentrations, this ion activates pyrophosphatase, as is the case with orthophosphatase. 4. It is concluded that, when interactions between metal ions and pyrophosphate are taken into account, the effects of these ions are consistent with the view that alkaline phosphatases possess both orthophosphatase and inorganic pyrophosphatase activities.

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