Retardation of calcium oxalate precipitation by glutamic-oxalacetic-transaminase activity

Nephrolithiasis is a highly prevalent condition, but its incidence varies depending on race, gender, and geographic location. Approximately half of patients form at least one recurrent stone within 10 years of the first episode. Renal stones are usually composed of calcium salts (calcium oxalate monohydrate or dihydrate, calcium phosphate), uric acid, or, less frequently, cystine and struvite (magnesium, ammonium, and phosphate). Calcium oxalate stones, the most commonly encountered ones, may result from urinary calcium oxalate precipitation on the Randall plaque, which is a hydroxyapatite deposit in the interstitium of the kidney medulla. Uric acid nephrolithiasis, which is common among patients with metabolic syndrome or diabetes mellitus, is caused by an excessively acidic urinary pH as a renal manifestation of insulin resistance. The medical evaluation of the kidney stone patient must be focused on identifying anatomic abnormalities of the urinary tract, associated systemic diseases, use of lithogenic drugs or supplements, and, mostly, urinary risk factors such as low urine volume, hypercalciuria, hyperuricosuria, hypocitraturia, hyperoxaluria, and abnormalities in urine pH that can be affected by dietary habits, environmental factors, and genetic traits. Metabolic evaluation requires a urinalysis, stone analysis (if available), serum chemistry, and urinary parameters, preferably obtained by two nonconsecutive 24-hour urine collections under a random diet. Targeted medication and dietary advice are effective to reduce the risk of recurrence. Clinical, radiologic, and laboratory follow-ups are needed to prevent stone growth and new stone formation, to assess treatment adherence or effectiveness to dietary recommendations, and to allow adjustment of pharmacologic treatment. This review contains 5 highly rendered figure, 3 tables, and 105 references.

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Control of cell shape by calcium in the euglenophyceae

Journal of Cell Science ◽

10.1242/jcs.49.1.99 ◽

1981 ◽

Vol 49 (1) ◽

pp. 99-117 ◽

Cited By ~ 1

Author(s):

J.M. Murray

Keyword(s):

Endoplasmic Reticulum ◽

Atpase Activity ◽

Calcium Oxalate ◽

Cell Shape ◽

Motor Units ◽

Astasia Longa ◽

Oxalate Precipitation ◽

Entire Cell ◽

The Individual ◽

Euglenoid Movement

The euglenoid flagellates are able to change their shape rapidly in response to a variety of stimuli, or sometimes spontaneously. Two extremes of shape can be identified: the “relaxed” form is cylindrical; the contracted form is a somewhat distorted disc. These 2 forms can be interconverted by treatments that alter the Ca2+ concentration of the entire cell. The level of Ca2+ is believed to be normally controlled by a system of calcium-accumulating membranes, identified in Astasia longa by the technique of calcium oxalate precipitation. The system forms a set of parallel tubes of endoplasmic reticulum, one of which lies immediately below each of the ridges of the pellicle. The individual ridges, each with its associated reticulum, microtubules and other elements are suggested to be independent motor units. Local activation of a small number of these units by Ca2+ is made possible by the arrangement of Ca2+ -sequestering reticulum, producing the characteristic squirming euglenoid movement. Uniform activation or suppression of all units produces the 2 extremes of shape. The pellicle of A. longa with its associated microtubules has been purified and shown to contain a Ca2+ -binding site and ATPase activity.

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GLUTAMIC OXALACETIC TRANSAMINASE ACTIVITY IN THE SERUM IN MUSCULAR DYSTROPHY AND OTHER NEUROMUSCULAR DISORDERS IN CHILDHOOD

PEDIATRICS ◽

10.1542/peds.22.6.1110 ◽

1958 ◽

Vol 22 (6) ◽

pp. 1110-1114

Author(s):

E. G. Murphy ◽

Morris M. Cherniak

Keyword(s):

Muscular Dystrophy ◽

Normal Values ◽

Advanced Disease ◽

Neuromuscular Disorders ◽

Transaminase Activity ◽

Older Children ◽

Younger Child ◽

Glutamic Oxalacetic Transaminase ◽

Small Series ◽

Group A

Serum activities of the enzyme glutamic oxalacetic transaminase were measured in 57 infants and children with various neuromuscular disorders. High values were obtained in 20 out of 32 patients with the Duchenne type of muscular dystrophy. The 12 cases with normal or borderline activities were mainly older children usually with advanced disease. Of the 10 patients with other varieties of muscular dystrophy, all but one had normal values. Normal values were invariably present in primary neuropathies. In the polymyositic group a small series of five cases had normal or borderline activities. The measurement of activity of this enzyme in the serum is a useful diagnostic aid in neuromuscular disorders, particularly in the younger child.

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Nephrolithiasis

10.2310/im.12042 ◽

2017 ◽

Author(s):

José Luiz Nishiura ◽

Ita Pfeferman Heilberg

Keyword(s):

Uric Acid ◽

Calcium Oxalate ◽

Dietary Habits ◽

Stone Formation ◽

Urine Volume ◽

First Episode ◽

Dietary Advice ◽

Dietary Recommendations ◽

Genetic Traits ◽

Oxalate Precipitation

Nephrolithiasis is a highly prevalent condition, but its incidence varies depending on race, gender, and geographic location. Approximately half of patients form at least one recurrent stone within 10 years of the first episode. Renal stones are usually composed of calcium salts (calcium oxalate monohydrate or dihydrate, calcium phosphate), uric acid, or, less frequently, cystine and struvite (magnesium, ammonium, and phosphate). Calcium oxalate stones, the most commonly encountered ones, may result from urinary calcium oxalate precipitation on the Randall plaque, which is a hydroxyapatite deposit in the interstitium of the kidney medulla. Uric acid nephrolithiasis, which is common among patients with metabolic syndrome or diabetes mellitus, is caused by an excessively acidic urinary pH as a renal manifestation of insulin resistance. The medical evaluation of the kidney stone patient must be focused on identifying anatomic abnormalities of the urinary tract, associated systemic diseases, use of lithogenic drugs or supplements, and, mostly, urinary risk factors such as low urine volume, hypercalciuria, hyperuricosuria, hypocitraturia, hyperoxaluria, and abnormalities in urine pH that can be affected by dietary habits, environmental factors, and genetic traits. Metabolic evaluation requires a urinalysis, stone analysis (if available), serum chemistry, and urinary parameters, preferably obtained by two nonconsecutive 24-hour urine collections under a random diet. Targeted medication and dietary advice are effective to reduce the risk of recurrence. Clinical, radiologic, and laboratory follow-ups are needed to prevent stone growth and new stone formation, to assess treatment adherence or effectiveness to dietary recommendations, and to allow adjustment of pharmacologic treatment. This review contains 5 highly rendered figure, 3 tables, and 105 references.

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Sources of Variation in a Standardized and a Semi-micro Procedure for the Spectrophotometric Assay of Serum Glutamic-Oxalacetic Transaminase Concentration

Clinical Chemistry ◽

10.1093/clinchem/4.5.392 ◽

1958 ◽

Vol 4 (5) ◽

pp. 392-408 ◽

Cited By ~ 11

Author(s):

A J Schneider ◽

Myron J Willis

Keyword(s):

Arrhenius Equation ◽

Spectrophotometric Assay ◽

Light Path ◽

Transaminase Activity ◽

Arrhenius Law ◽

Glutamic Oxalacetic Transaminase ◽

Sources Of Variation ◽

The Mean ◽

Serum Glutamic Oxalacetic Transaminase ◽

Temperature Factors

Abstract 1. Both a standard method and a semi-micro method for the spectrophotometric assay of serum glutamic-oxalacetic transaminase (S-GOT) concentrations have been described. 2. Either procedure is associated with an error defined by a factor of less than 1.03. 3. The temperature dependence of the rate of transamination was shown to follow Arrhenius' law over the range of temperature from 25° to 38°. 4. A tabulation of temperature factors calculated from the derived Arrhenius equation was presented. These factors permit correction of rates observed at temperature T to rates expected at 32°. 5. A comparison of normal S-GOT values from various sources was made, with correction for temperature differences. Based on 779 values from four different laboratories, the combined mean for adults was 21.9. 6. A standard unit of transaminase activity was defined and referred to as a Karmen unit. A Karmen unit represents that amount of transaminase in 1 ml. of sample which will cause a decrease in optical density at 340 mµ of 0.001 per minute at a temperature of 32°, an effective light path of 1 cm., and a volume of test solution of 3 ml. According to this definition, the mean normal adult S-GOT concentration is 21.9 Karmen units. The practical upper limit of normal will be defined in another publication.

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A Study of the Colorimetric Dinitrophenylhydrazine Method for the Determination of Serum Glutamic Oxalacetic Transaminase Activity

Clinical Chemistry ◽

10.1093/clinchem/12.4.217 ◽

1966 ◽

Vol 12 (4) ◽

pp. 217-225 ◽

Cited By ~ 3

Author(s):

J S Annino

Keyword(s):

Enzyme Activity ◽

Transaminase Activity ◽

Reagent Blank ◽

Glutamic Oxalacetic Transaminase ◽

Color Development ◽

High Enzyme ◽

Serum Glutamic Oxalacetic Transaminase ◽

The Relationship ◽

High Enzyme Activity

Abstract Study of the colorimetric transaminase method of Reitman and Frankel for the determination of serum glutamic oxalacetic transaminase activity revealed the following: (1) although maximum absorption occurs at 444 mµ, absorbance readings at 505 mµ gave satisfactory results; (2) color development is immediate and the color is stable for at least 1 hr.; (3) a pyruvate calibration standard may be used; (4) sample blanks are not usually necessary; (5) a reagent blank should accompany each group of analyses and should be used as a photometric reference; (6) the relationship between dilution and enzyme activity is linear; and (7) although the relationship between incubation time and activity is not exactly linear, a factor has been determined to permit the use of a 12-min. incubation period with samples showing high enzyme activity.

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