Biomaterial Database

Measurement of the risk of calcium phosphate crystallization in urine. 1987

H G Tiselius

A method is described for analysis of the risk of calcium phosphate (CaP) crystallization in urine samples. The pH required for formation of 500 crystals in the size range 3.5 to 5 micron (pHCaP) was determined in a Coulter Counter following addition of sodium hydroxide. The risk of CaP crystallization (CaP-CR) was defined as: 1/(pHCaP--5.8). CaP-CR was determined in 24 h urine collections from 25 patients with calcium stone disease and 26 normal subjects, each urine diluted to a creatinine concentration of 5 mumol per ml. The mean (+/- SD) CaP-CR was 0.71 +/- 0.18 and 0.63 +/- 0.14 respectively and did not differ significantly. This method might be useful for evaluations and follow-up of stone formers with respect to the risk of CaP precipitation and stone formation.

UI	MeSH Term	Description	Entries
D008851	Micropore Filters	A membrane or barrier with micrometer sized pores used for separation purification processes.	Millipore Filters,Filter, Micropore,Filter, Millipore,Filters, Micropore,Filters, Millipore,Micropore Filter,Millipore Filter
D010316	Particle Size	Relating to the size of solids.	Particle Sizes,Size, Particle,Sizes, Particle
D002130	Calcium Phosphates	Calcium salts of phosphoric acid. These compounds are frequently used as calcium supplements.	Phosphates, Calcium
D003460	Crystallization	The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Crystalline Polymorphs,Polymorphism, Crystallization,Crystal Growth,Polymorphic Crystals,Crystal, Polymorphic,Crystalline Polymorph,Crystallization Polymorphism,Crystallization Polymorphisms,Crystals, Polymorphic,Growth, Crystal,Polymorph, Crystalline,Polymorphic Crystal,Polymorphisms, Crystallization,Polymorphs, Crystalline
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D012306	Risk	The probability that an event will occur. It encompasses a variety of measures of the probability of a generally unfavorable outcome.	Relative Risk,Relative Risks,Risk, Relative,Risks,Risks, Relative
D014545	Urinary Calculi	Low-density crystals or stones in any part of the URINARY TRACT. Their chemical compositions often include CALCIUM OXALATE, magnesium ammonium phosphate (struvite), CYSTINE, or URIC ACID.	Urinary Stones,Urinary Tract Stones,Calculi, Urinary,Calculus, Urinary,Stone, Urinary,Stone, Urinary Tract,Stones, Urinary,Stones, Urinary Tract,Urinary Calculus,Urinary Stone,Urinary Tract Stone