Ultrafiltration of Human Urine Affects Calcium Oxalate Monohydrate (COM) Crystallization Kinetics

1994 ◽  
pp. 297-298
Author(s):  
D. T. Erwin ◽  
J. Alam ◽  
D. J. Kok ◽  
A. Annaloro ◽  
J. Vaughn ◽  
...  
Keyword(s):  
Calcium Oxalate ◽  
Crystallization Kinetics ◽  
Human Urine ◽  
Calcium Oxalate Monohydrate

Effect of Urate on Calcium Oxalate Crystallization in Human Urine: Evidence for a Promotory Role of Hyperuricosuria in Urolithiasis

1990 ◽  
Vol 79 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Rosemary L. Ryall ◽  
Villis R. Marshall
Keyword(s):  
Calcium Oxalate ◽  
Human Urine ◽  
Stone Formation ◽  
Calcium Oxalate Monohydrate ◽  
Convincing Evidence ◽  
Urine Samples ◽  
Type B ◽  
Calcium Oxalate Dihydrate ◽  
Median Volume ◽  
The Individual

1. The effect of hyperuricosuria, simulated by increasing the concentration of dissolved urate, on the crystallization of calcium oxalate in human urine was examined. 2. Twenty urine samples were studied. Ten of these, designated type A, spontaneously precipitated calcium oxalate dihydrate crystals upon the addition of a solution of sodium urate solution which raised the median urate concentration from 3.1 to 7.0 mmol/l. 3. Adding dissolved urate to the remaining type B samples raised the median urate concentration from 2.2 to 6.2 mmol/l, but did not cause the precipitation of calcium oxalate. This was induced in these samples by the addition of a standard load of oxalate above an empirically determined metastable limit. 4. In the type B urine samples, the addition of urate decreased the median metastable limit from 125 to 66 μmol of oxalate, trebled the median volume of crystalline calcium oxalate deposited from 35 000 to 105 000 μm3/μl and significantly increased the overall size of the particles precipitated. Calcium oxalate monohydrate was exclusively precipitated, and the individual crystals deposited in the presence of urate were markedly smaller, more numerous, and more highly aggregated than those produced in its absence. 5. These results constitute the most convincing evidence yet obtained that hyperuricosuria may be a powerful promoter of calcium oxalate stone formation.

scholarly journals Modulation of calcium oxalate monohydrate crystallization kinetics in vitro

1988 ◽  
Vol 34 (3) ◽  
pp. 346-350 ◽  
Author(s):  
Dik J. Kok ◽  
Socrates E. Papafoulos ◽  
Leo J.M.J. Blomen ◽  
Olav L.M. Bijvoet
Keyword(s):  
Calcium Oxalate ◽  
Crystallization Kinetics ◽  
Calcium Oxalate Monohydrate

scholarly journals The effects of intracrystalline and surface-bound proteins on the attachment of calcium oxalate monohydrate crystals to renal cells in undiluted human urine

2010 ◽  
Vol 105 (5) ◽  
pp. 708-715 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Lauren A. Thurgood ◽  
Tingting Wang ◽  
Rosemary L. Ryall
Keyword(s):  
Calcium Oxalate ◽  
Human Urine ◽  
Calcium Oxalate Monohydrate ◽  
Renal Cells

Effect of urine fractionation on attachment of calcium oxalate crystals to renal epithelial cells: implications for studying renal calculogenesis

2007 ◽  
Vol 292 (5) ◽  
pp. F1396-F1403 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Lauren A. Thurgood ◽  
Rosemary L. Ryall
Keyword(s):  
Calcium Oxalate ◽  
Western Blotting ◽  
Human Urine ◽  
Mdck Cells ◽  
Calcium Oxalate Monohydrate ◽  
Binding Medium ◽  
Madin Darby Canine Kidney ◽  
Sds Page ◽  
Crystal Adhesion ◽  
Darby Canine Kidney

Our aim was to determine whether fractionation of human urine affects the attachment of calcium oxalate monohydrate (COM) crystals to renal cells. Urine collected from six healthy subjects was fractionated into sieved (S), centrifuged (C), centrifuged and filtered (CF), or ultrafiltered (UF). Attachment of [14C]COM crystals to Madin-Darby canine kidney (MDCK) cells was studied after precoating the crystals or the cells with the urine fractions and by using the same fractions as the binding medium. Protein content of the fractions and precoated crystals was analyzed with SDS-PAGE and Western blotting. All urine fractions inhibited crystal attachment. When fractions from the six urine samples were used to precoat the cells, the median inhibitions of crystal adhesion (∼40%) were not significantly different. Median inhibition after preincubation of crystals was the same for the S, C, and CF fractions (∼40%) but significantly greater than for the UF fraction (∼28%). When fractions were used as the binding medium, median inhibitions decreased from 64% in the S fraction to 47 (C), 42 (CF), and to 29% (UF). SDS-PAGE analysis showed that centrifugation and filtration reduced the amount of Tamm-Horsfall glycoprotein (THG), which was confirmed by Western blotting. Human serum albumin, urinary prothrombin fragment 1, and osteopontin, but not THG, were present in demineralized extracts of the precoated crystals. Fractionation of human urine affects the attachment of COM crystals to MDCK cells. Hence future studies investigating regulation of crystal-cell interactions should be carried out in untreated urine as the binding medium.

Modulation of calcium oxalate monohydrate crystallization kinetics by urine of preterm neonates

2001 ◽  
Vol 38 (6) ◽  
pp. 1229-1234 ◽  
Author(s):  
Eveline A. Schell-Feith ◽  
Ivo Que ◽  
Dirk J. Kok ◽  
Joana E. Kist-van Holthe ◽  
Esther Kühler ◽  
...  
Keyword(s):  
Calcium Oxalate ◽  
Crystallization Kinetics ◽  
Calcium Oxalate Monohydrate ◽  
Preterm Neonates

Molecular abnormality of Tamm-Horsfall glycoprotein in calcium oxalate nephrolithiasis

1991 ◽  
Vol 260 (4) ◽  
pp. F569-F578 ◽  
Author(s):  
B. Hess ◽  
Y. Nakagawa ◽  
J. H. Parks ◽  
F. L. Coe
Keyword(s):  
Calcium Oxalate ◽  
Human Urine ◽  
Calcium Oxalate Monohydrate ◽  
The Other ◽  
Effective Interactions ◽  
Crystal Aggregation ◽  
Molecular Abnormality ◽  
Self Aggregation

Tamm-Horsfall glycoprotein (THP) inhibits self-aggregation of calcium oxalate monohydrate (COM) crystals and may therefore be part of the natural defenses against deposition of COM in the kidney in the form of stones or nephrocalcinosis. We have studied THP from six patients with severe nephrolithiasis and have found that their THP inhibits COM self-aggregation less than normal THP under conditions of NaCl and THP concentration and pH similar to those of human urine. The reason for the reduced inhibition of COM crystal aggregation seems to be an enhanced self-aggregation of patient THP, which removes it from effective interactions with the COM crystals. In one family, the father and the oldest son both excreted THP that behaved abnormally and in similar ways, whereas THP from the other son and from the wife behaved normally.

Calcium oxalate crystallization kinetics studied by oxalate-induced turbidity in fresh human urine and artificial urine

2000 ◽  
Vol 98 (2) ◽  
pp. 151-158 ◽  
Author(s):  
J. P. KAVANAGH ◽  
L. JONES ◽  
P. N. RAO
Keyword(s):  
Calcium Oxalate ◽  
Crystallization Kinetics ◽  
Human Urine ◽  
Calcium Concentration ◽  
Rate Of Change ◽  
Growth Rate Constant ◽  
Supersaturation Ratio ◽  
Calcium Oxalate Crystallization ◽  
Oxalate Concentration ◽  
Artificial Urine

We have studied the kinetics of oxalate-induced turbidity in fresh human urine and artificial urine. Assays are performed in 96-well plates, which allows many oxalate concentrations to be studied, repeatedly, in a short time. The metastable limit is defined in terms of the lowest oxalate concentration that gives a rate of change of attenuance significantly greater than the control. Interpretation of rates above this limit is based on ln/ln plots of initial rates against added oxalate concentration. This approach has a good theoretical basis, is well supported by our results and gives a turbidity rate index that is related to the product of the growth rate constant and a factor relating to the number and characteristics of the heteronuclei responsible for initiation of crystallization. This interpretation is posited upon the assumptions that second-order crystallization kinetics occur in unseeded urine when supersaturation exceeds the metastable limit and that aggregation during the initial phase of crystallization does not significantly contribute to changes in turbidity. Metastable limits of urine from healthy volunteers corresponded to a calcium oxalate supersaturation ratio of approx. 10. The turbidity rate index was higher in human urine than in artificial urine. The metastable limit, based on either oxalate concentration or supersaturation, for induction of calcium oxalate crystallization in normal human urine is higher than is likely to be found in normal subjects in vivo. The shape of the relationship between the metastable limit (based on oxalate concentration) and calcium concentration emphasizes the benefit of achieving a low urine calcium concentration. Comparison of the turbidity rate indices for human and artificial urine suggests that the role of nucleation promoters is more dominant than that of growth inhibitors.

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