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

2000 ◽  
Vol 98 (2) ◽  
pp. 151 ◽  
Author(s):  
J.P. KAVANAGH ◽  
L. JONES ◽  
P.N. RAO
2000 ◽  
Vol 98 (2) ◽  
pp. 151-158 ◽  
Author(s):  
J. P. KAVANAGH ◽  
L. JONES ◽  
P. N. RAO

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.


PLoS ONE ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. e0218734 ◽  
Author(s):  
Roberta De Bellis ◽  
Maria Piera Piacentini ◽  
Maria Assunta Meli ◽  
Michele Mattioli ◽  
Michele Menotta ◽  
...  

2014 ◽  
Vol 26 (3) ◽  
pp. 835-840
Author(s):  
Jun-Jun Li ◽  
Jun-Fa Xue ◽  
Meng Xu ◽  
Jian-Ming Ouyang

1994 ◽  
pp. 297-298
Author(s):  
D. T. Erwin ◽  
J. Alam ◽  
D. J. Kok ◽  
A. Annaloro ◽  
J. Vaughn ◽  
...  

1977 ◽  
Vol 117 (3) ◽  
pp. 342-345 ◽  
Author(s):  
John D. Miller ◽  
Alan D. Randolph ◽  
George W. Drach

1997 ◽  
Vol 306 (1-2) ◽  
pp. 7-12 ◽  
Author(s):  
O. Söhnel ◽  
M. Kroupa ◽  
G. Franková ◽  
V. Velich

2014 ◽  
Vol 881-883 ◽  
pp. 708-711
Author(s):  
Lan Qing Deng ◽  
Jun Fa Xue ◽  
Li Kuan ◽  
Jian Ming Ouyang

The crystallization kinetics of calcium oxalate (CaOx) was comparatively studied by detecting the change of free Ca2+ ions concentration with the reaction time in artificial urine and in saline system. The dynamics equations of CaOx crystallization was r=kcα, and the average reaction order (α) was 3.3 regardless of the relative suprasaturation degree (RS) of CaOx in the range of RS=10.58~17.53. The average reaction rate constant (κ) was (0.97±0.1)×109 in artificial urine and κ=(3.1±1.8)×109 in saline system, due to the presence of inhibitors to CaOx crystallization in artificial urine.


1990 ◽  
Vol 190 (3) ◽  
pp. 223-238 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Rosemary L. Ryall ◽  
Villis R. Marshall

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