Calcium Oxalate Precipitation in Model Systems Mimicking the Conditions of Hyperoxaluria

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

Urological Research ◽

10.1007/bf00255939 ◽

1982 ◽

Vol 10 (4) ◽

Cited By ~ 3

Author(s):

R. Azoury ◽

S. Sarig ◽

N. Garti ◽

S. Perlberg

Keyword(s):

Calcium Oxalate ◽

Transaminase Activity ◽

Glutamic Oxalacetic Transaminase ◽

Oxalate Precipitation

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A Simplified Technique for Determination of Small Amounts of Calcium as Oxalate

Clinical Chemistry ◽

10.1093/clinchem/10.4.352 ◽

1964 ◽

Vol 10 (4) ◽

pp. 352-365

Author(s):

Donald D Van Slyke ◽

Paul E Carson

Keyword(s):

Acid Solution ◽

Calcium Oxalate ◽

Perchloric Acid ◽

Perchloric Acid Solution ◽

Ceric Sulfate ◽

Glass Filter ◽

Oxalate Precipitation ◽

Oxalate Solution ◽

Filter Tube

Abstract Procedures for determination of calcium by oxalate precipitation are reviewed, and a method is described in which the calcium oxalate precipitate is both formed and washed in a filter tube with a fritted-glass filter. Washing with saturated calcium oxalate solution is completed in 1-2 min. The washed precipitate is redissolved in perchloric acid solution and the dissolved oxalate is either titrated or determined manometrically by the CO2 evolved from oxidation with ceric sulfate.

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Examination of the Urinary Potential of Hyperuricosuric Patients to Retard Calcium Oxalate Precipitation

European Urology ◽

10.1159/000472447 ◽

1985 ◽

Vol 11 (1) ◽

pp. 40-43

Author(s):

Benad Goldwasser ◽

Sara Sarig ◽

Reuven Azoury ◽

Sara Orda ◽

Hayim Boichis ◽

...

Keyword(s):

Calcium Oxalate ◽

Oxalate Precipitation

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Real Time Monitoring of Calcium Oxalate Precipitation Reaction by Using Corrosion Resistant Magnetoelastic Resonance Sensors

Sensors ◽

10.3390/s20102802 ◽

2020 ◽

Vol 20 (10) ◽

pp. 2802 ◽

Cited By ~ 2

Author(s):

Beatriz Sisniega ◽

Ariane Sagasti Sedano ◽

Jon Gutiérrez ◽

Alfredo García-Arribas

Keyword(s):

Corrosion Resistance ◽

Calcium Oxalate ◽

Real Time ◽

Excitation Frequency ◽

Resonance Curve ◽

Time Interval ◽

Precipitation Reaction ◽

Oxalate Precipitation ◽

Pre Treatment ◽

Magnetoelastic Resonance

The magnetoelastic resonance is used to monitor the precipitation reaction of calcium oxalate ( C a C 2 O 4 ) crystals in real-time, by measuring the shift of the resonance frequency caused by the mass increase on the resonator. With respect to previous work on the same matter, the novelty lies in the adoption of an amorphous ferromagnetic alloy, of composition F e 73 C r 5 S i 10 B 12 , as resonator, that replaces the commercial Metglas® 2826 alloy (composition F e 40 N i 38 M o 4 B 18 ). The enhanced corrosion resistance of this material allows it to be used in biological environments without any pre-treatment of its surface. Additionally, the measurement method, which has been specifically adapted to this application, allows quick registration of the whole resonance curve as a function of the excitation frequency, and thus enhances the resolution and decreases the detection noise. The frequency shift is calibrated by the static deposition of well-known masses of C a C 2 O 4 . The resonator dimensions have been selected to improve sensitivity. A 20 mm long, 2 mm wide and 25 μ m thick magnetoelastic resonator has been used to monitor the precipitation reaction of calcium oxalate in a 500 s time interval. The results of the detected precipitated mass when oxalic acid and calcium chloride are mixed in different concentrations (30 mM, 50 mM and 100 mM) are presented as a function of time. The results show that the sensor is capable of monitoring the precipitation reaction. The mass sensitivity obtained, and the corrosion resistance of the material, suggest that this material can perform excellently in monitoring this type of reaction.

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