FREEZING DAMAGE TO BOVINE CREAM INDICATED BY RELEASE OF ENZYMES

1959 ◽  
Vol 37 (7) ◽  
pp. 821-827 ◽  
Author(s):  
L. J. N. Cole ◽  
D. Kluepfel ◽  
C. V. Lusena

When washed cream was frozen slowly and thawed, some breaking of the emulsion occurred and on centrifugation a pellet, mostly membrane material, was obtained. Xanthine oxidase and alkaline phosphatase were present in this pellet, but little enzyme activity was found in the aqueous phase. The main effect of slow freezing was to force the fat globules together so that alteration and redistribution of the membranes could occur, and, on thawing, fat could coalesce. Rapid freezing on the other hand distributed fat globules more evenly so that less coalescence could occur on thawing.

1959 ◽  
Vol 37 (1) ◽  
pp. 821-827 ◽  
Author(s):  
L. J. N. Cole ◽  
D. Kluepfel ◽  
C. V. Lusena

When washed cream was frozen slowly and thawed, some breaking of the emulsion occurred and on centrifugation a pellet, mostly membrane material, was obtained. Xanthine oxidase and alkaline phosphatase were present in this pellet, but little enzyme activity was found in the aqueous phase. The main effect of slow freezing was to force the fat globules together so that alteration and redistribution of the membranes could occur, and, on thawing, fat could coalesce. Rapid freezing on the other hand distributed fat globules more evenly so that less coalescence could occur on thawing.


1970 ◽  
Vol 27 (2) ◽  
pp. 383-390 ◽  
Author(s):  
Eugene Jackim ◽  
Janice M. Hamlin ◽  
Stephen Sonis

Activities of five liver enzymes (acid and alkaline phosphatase, catalase, xanthine oxidase, and ribonuclease) from Fundulus heteroclitus surviving exposure to 96-hr TLm concentrations of salts of six metals (lead, copper, mercury, beryllium, cadmium, and silver) differed markedly from those of unexposed fish. Changes in enzyme activity produced by the exposures were not necessarily the same in magnitude or direction as those observed when the salts were introduced directly into the enzyme preparations. It is proposed that changes in liver enzyme activity may be useful as a kind of biochemical autopsy tool for diagnosing sublethal metal poisoning in fish.


2011 ◽  
Vol 51 (No. 12) ◽  
pp. 523-531 ◽  
Author(s):  
J. Wyszkowska ◽  
J. Kucharski ◽  
E. Boros

The effect of soil contamination with nickel applied in the doses of 100, 200, 300 and 400 mg Ni/kg of soil on the activity of dehydrogenases, urease and acid and alkaline phosphatase was studied in a pot experiment. Heavy loamy sand and silty light loam were used in the experiment that comprised of two series: with spring barley cultivation and without plant cultivation. The enzyme activity was determined on day 14, 28, 42 and 56 of the experiment. Based on the study, it was found that soil contamination with nickel applied as NiCl<sub>2</sub>.6 H<sub>2</sub>O decreased the activity of dehydrogenases, urease and acid and alkaline phosphatase. This decrease was determined by the applied dose of this metal. Nickel exhibited a stronger effect on the soil with spring barley cultivation than on the unsown soil. In the heavy loamy sand sown with spring barley, more than 50% inhibition of the activity of dehydrogenases was caused by 300&nbsp;and 400 mg Ni contamination, and in the case of urease by 200, 300 and 400 mg Ni/kg of soil. In the silty light loam sown with spring barley, more than 50% decrease in the activity of dehydrogenases and alkaline phosphatase was observed under 400 mg Ni contamination. The inhibition of the other enzyme activities did not exceed 50%. Urease and alkaline phosphatase exhibited a higher activity in the heavier soil, whereas dehydrogenases and acid phosphatase exhibited a higher activity in the lighter soil. In the nickel-free soil, spring barley cultivation had a positive effect on the enzyme activity and a positive correlation between the spring barley yield and the activity of dehydrogenases, urease and acid and alkaline phosphatase was observed.


1966 ◽  
Vol 101 (3) ◽  
pp. 651-660 ◽  
Author(s):  
WK Downey ◽  
P Andrews

1. The tributyrinases in milk are mainly associated with casein micelles. Dilution or addition of sodium chloride increases the enzyme activity, probably by dissociating the micelle-tributyrinase complexes. 2. Tributyrinase activities of milks activated by dilution and sodium chloride addition were in the range 0.2-1.7muequiv. of acid liberated/ml. of milk/min. from tributyrin emulsion at pH8.5 and 25 degrees . The enzymes have a bivalent-cation requirement for full activity and are rather unstable when separated from casein. 3. Ultracentrifugation of skim milks containing sodium chloride (0.75m) gave preparations low in casein but containing about 70% of the milk tributyrinases. The tributyrinases in such preparations appear to be bound in complexes of molecular weight about 350000. Dilution may result in dissociation to give the free enzymes. 4. Pancreatic lipase also formed complexes with casein micelles, but wheat-germ esterase, xanthine oxidase, milk alkaline phosphatase and other enzymes did not.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bradley S. Peterson ◽  
Amy E. West ◽  
John R. Weisz ◽  
Wendy J. Mack ◽  
Michele D. Kipke ◽  
...  

Abstract Background Treatment of a child who has an anxiety disorder usually begins with the question of which treatment to start first, medication or psychotherapy. Both have strong empirical support, but few studies have compared their effectiveness head-to-head, and none has investigated what to do if the treatment tried first isn’t working well—whether to optimize the treatment already begun or to add the other treatment. Methods This is a single-blind Sequential Multiple Assignment Randomized Trial (SMART) of 24 weeks duration with two levels of randomization, one in each of two 12-week stages. In Stage 1, children will be randomized to fluoxetine or Coping Cat Cognitive Behavioral Therapy (CBT). In Stage 2, remitters will continue maintenance-level therapy with the single-modality treatment received in Stage 1. Non-remitters during the first 12 weeks of treatment will be randomized to either [1] optimization of their Stage 1 treatment, or [2] optimization of Stage 1 treatment and addition of the other intervention. After the 24-week trial, we will follow participants during open, naturalistic treatment to assess the durability of study treatment effects. Patients, 8–17 years of age who are diagnosed with an anxiety disorder, will be recruited and treated within 9 large clinical sites throughout greater Los Angeles. They will be predominantly underserved, ethnic minorities. The primary outcome measure will be the self-report score on the 41-item youth SCARED (Screen for Child Anxiety Related Disorders). An intent-to-treat analysis will compare youth randomized to fluoxetine first versus those randomized to CBT first (“Main Effect 1”). Then, among Stage 1 non-remitters, we will compare non-remitters randomized to optimization of their Stage 1 monotherapy versus non-remitters randomized to combination treatment (“Main Effect 2”). The interaction of these main effects will assess whether one of the 4 treatment sequences (CBT➔CBT; CBT➔med; med➔med; med➔CBT) in non-remitters is significantly better or worse than predicted from main effects alone. Discussion Findings from this SMART study will identify treatment sequences that optimize outcomes in ethnically diverse pediatric patients from underserved low- and middle-income households who have anxiety disorders. Trial registration This protocol, version 1.0, was registered in ClinicalTrials.gov on February 17, 2021 with Identifier: NCT04760275.


1975 ◽  
Vol 23 (5) ◽  
pp. 342-347 ◽  
Author(s):  
A Linde ◽  
B C Magnusson

The effects of the alkaline phosphatase inhibitors levamisole and R 8231 on p-nitro-phenylphosphatase, inorganic pyrophosphatase and adenosine triphosphatase (ATPase) activities in dentingenically active odontoblasts were studied. The p-nitrophenylphosphatase and inorganic pyrophosphatase activities were inhibited, while 40% of the ATP-splitting enzyme activity remained under the assay condition used. This finding, togeather with earlier studies, indicates that at least two different phosphatase are active at alkaline pH in hard tissue-forming cells; on nonspecific alkaline phosphatase and one specific ATPase. The ATPase activity is uninfluenced by ouabain and ruthenium red and is activated by Ca-2+ ions.


1979 ◽  
Vol 183 (1) ◽  
pp. 73-81 ◽  
Author(s):  
R Felix ◽  
H Fleisch

1. Dichloromethanediphosphonate and to a lesser degree 1-hydroxyethane-1,1-diphosphonate, two compounds characterized by a P-C-P bond, increased the alkaline phosphatase activity of cultured rat calvaria cells up to 30 times in a dose-dependent fashion. 2. Both diphosphonates also slightly inhibited the protein synthesis in these cells. 3. Thymidine, an inhibitor of cell division, did not inhibit the induction of the enzyme, indicating that the increase in enzyme activity was not due to the formation of a specific population of cells with high alkaline phosphatase activity. 4. The effect on alkaline phosphatase was suppressed by the addition of cycloheximide, an inhibitor of protein synthesis. 5. After subculturing the stimulated cells in medium without diphosphonates, the enzyme activity fell almost to the control value. 6. Bovine parathyrin diminished the enzyme activity of the control cells and the cells treated with dichloromethanediphosphonate; however, at high concentration the effect of parathyrin was greater on the diphosphonate-treated cells than on the control cells. 7. The electrophoretic behaviour, heat inactivation, inhibition by bromotetramisole or by phenylalanine, and the Km value of the induced enzyme were identical with that of the control enzyme.


1972 ◽  
Vol 129 (3) ◽  
pp. 645-655 ◽  
Author(s):  
J. S. Heller ◽  
C. L. Villemez

A neutral-detergent-solubilized-enzyme preparation derived from Phaseolus aureus hypocotyls contains two types of glycosyltransferase activity. One, mannosyltransferase enzyme activity, utilizes GDP-α-d-mannose as the sugar nucleotide substrate. The other, glucosyltransferase enzyme activity, utilizes GDP-α-d-glucose as the sugar nucleotide substrate. The soluble enzyme preparation catalyses the formation of what appears to be a homopolysaccharide when either sugar nucleotide is the only substrate present. A β-(1→4)-linked mannan is the only polymeric product when only GDP-α-d-mannose is added. A β-(1→4)-linked glucan is the only polymeric product when only GDP-α-d-glucose is added. In the presence of both sugar nucleotides, however, a β-(1→4)-linked glucomannan is formed. There are indications that endogenous sugar donors may be present in the enzyme preparation. There appear to be only two glycosyltransferases in the enzyme preparation, each catalysing the transfer of a different sugar to the same type of acceptor molecule. The glucosyltransferase requires the continual production of mannose-containing acceptor molecules for maintenance of enzyme activity, and is thereby dependent upon the activity of the mannosyltransferase. The mannosyltransferase, on the other hand, does not require the continual production of glucose-containing acceptors for maintenance of enzyme activity, but is severely inhibited by GDP-α-P-glucose. These properties promote the synthesis of β-(1→4)-linked glucomannan rather than β-(1→4)-linked glucan plus β-(1→4)-linked mannan when both sugar nucleotide substrates are present.


1977 ◽  
Vol 163 (3) ◽  
pp. 635-637 ◽  
Author(s):  
R H Quarles ◽  
C F Pasnak

Treatment of the chloroform/methanol-insoluble residue of rat brain myelin with lithium 3,5-di-iodosalicylate solubilized the major myelin-associated glycoprotein along with most other proteins and glycoproteins. Equilibration of the extract with phenol resulted in the selective partitioning of the major glycoprotein into the aqueous phase, whereas nearly all of the other proteins and glycoproteins went into the phenol phase.


PEDIATRICS ◽  
1959 ◽  
Vol 24 (3) ◽  
pp. 360-361
Author(s):  
SAMUEL P. BESSMAN

THE MEASUREMENT of enzyme activity of serum as an indicator of disease has a long history in medicine. In the past, it has been the aim of the designers of these methods to make them as specific as possible for assay of an enzyme characteristic of a particular system or group of similar organs. Examples of these venerable tests are those for amylase, acid phosphatase, alkaline phosphatase and choline esterase in the serum. Warburg made the first departure from this specificity by demonstrating that the activity of triosephosphate dehydrogenase in the serum of animals with cancer was much greater than that of controls. This test was partially specific, for as Warburg had earlier shown, the glycolytic activity of tumors is much greater than that of normal tissues. The non-specific approach became extreme with the introduction of the measurement of the glutamic-oxalacetic transaminase reaction in the diagnosis of acute coronary disease.


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