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New chemolysis for urological calcium phosphate calculi - a study in vitro.

Xiang-bo Z, Zhi-ping W, Jian-min D, Jian-zhong L, Bao-liang M - BMC Urol (2005)

Bottom Line: Diluted twice, S1 and S2 had even better effectiveness than their initial solution.The additive of Na+, K+ or Ca2+ greatly reduced the dissolution rates of S1, S2.Our data indicate that test solutions S1 and S2 are effective solvents in the chemolysis of calcium phosphate stones.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Life Sciences, LanZhou University, LanZhou, 730030, China. zhangxb4@tom.com

ABSTRACT

Background: Advances in techniques have left very few indications for open surgical extraction of urinary stones currently. These advances notwithstanding, the search continues for medical approaches to urinary stone management. In this study, we perform an in vitro study analyzing the efficiency and prospect of two new complex solutions in urological calcium phosphate calculi dissolution.

Methods: Eighteen stones composed mainly of calcium phosphates were taken from patients who underwent kidney stone surgery. These stones were large enough (weight range 0.514-0.928 g) to be fragmented and matched equally into six groups. Chemolysis of phosphate stones was done with six different solvents and was repeated 3 times with 6 stones for each solution. At 24, 48 and 72 h, reduction in weight, percentage weight change, and dissolution rate; the dissolution rates at pH 5.0, 7.0 and 8.5 for each solution, using different cations (Na+, K+ or Ca2+), according to different dilutions (1:1, 1:2, 1:3, 1:4) of S1 and S2 were simultaneously determined.

Results: Calcium phosphate calculi were poorly dissolved by Phys and Art, and they had a low dissolution rate in pH 8.5 EDTA. The most effective solutions were S1, S2 and R, with 72 h mean dissolution rates: 5.75 +/- 0.44 mg/hr (S1), 5.2 +/- 0.63 mg/hr (S2), 4.55 +/- 0.46 mg/hr (R) (x +/- s, p < 0.01 R, S1 and S2 vs Phys, Art and EDTA; p < 0.05, S1 vs R, LSD-test). The mean percentage weight loss at 72 h was: 52.1 +/- 15.75 % (S1), 44.4 +/- 7.37 % (S2) and 40.5 +/- 3.67 % (R) ( x +/- s, p < 0.01 R, S1 and S2 vs Phys, Art and EDTA, LSD-test). Diluted twice, S1 and S2 had even better effectiveness than their initial solution. The additive of Na+, K+ or Ca2+ greatly reduced the dissolution rates of S1, S2.

Conclusion: Our data indicate that test solutions S1 and S2 are effective solvents in the chemolysis of calcium phosphate stones. At twice dilutions, these solutions are even more useful in the treatment of stone disease.

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Effectiveness of six solvents at different pH (mg/hr). Phys = physiologic sodium chloride solution, Art = artificial urine, EDTA = 0.03 M disodium EDTA+TEA, R = renacidin, S1 = test solution 1, S2 = test solution 2.
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Figure 2: Effectiveness of six solvents at different pH (mg/hr). Phys = physiologic sodium chloride solution, Art = artificial urine, EDTA = 0.03 M disodium EDTA+TEA, R = renacidin, S1 = test solution 1, S2 = test solution 2.

Mentions: The dissolution rates were pH dependent. Even Phys and Art were effective to some extent at pH 4. The addition of 1 mol/L sodium hydroxide 10 ml into S1 or S2 100 ml, though not enough to lead to a detectable pH rise, would make the solutions cloudy and greatly reduce their effectiveness. At pH 5.0 they were nearly ineffective, as also observed at pH 7.0, 8.5. However, the dissolution rate of EDTA increased at an elevated pH value. At pH 8.5, EDTA approached a maximum dissolution rate with 72 h mean 1.56 ± 0.05 mg/hr (Figure 2).


New chemolysis for urological calcium phosphate calculi - a study in vitro.

Xiang-bo Z, Zhi-ping W, Jian-min D, Jian-zhong L, Bao-liang M - BMC Urol (2005)

Effectiveness of six solvents at different pH (mg/hr). Phys = physiologic sodium chloride solution, Art = artificial urine, EDTA = 0.03 M disodium EDTA+TEA, R = renacidin, S1 = test solution 1, S2 = test solution 2.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC1173122&req=5

Figure 2: Effectiveness of six solvents at different pH (mg/hr). Phys = physiologic sodium chloride solution, Art = artificial urine, EDTA = 0.03 M disodium EDTA+TEA, R = renacidin, S1 = test solution 1, S2 = test solution 2.
Mentions: The dissolution rates were pH dependent. Even Phys and Art were effective to some extent at pH 4. The addition of 1 mol/L sodium hydroxide 10 ml into S1 or S2 100 ml, though not enough to lead to a detectable pH rise, would make the solutions cloudy and greatly reduce their effectiveness. At pH 5.0 they were nearly ineffective, as also observed at pH 7.0, 8.5. However, the dissolution rate of EDTA increased at an elevated pH value. At pH 8.5, EDTA approached a maximum dissolution rate with 72 h mean 1.56 ± 0.05 mg/hr (Figure 2).

Bottom Line: Diluted twice, S1 and S2 had even better effectiveness than their initial solution.The additive of Na+, K+ or Ca2+ greatly reduced the dissolution rates of S1, S2.Our data indicate that test solutions S1 and S2 are effective solvents in the chemolysis of calcium phosphate stones.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Life Sciences, LanZhou University, LanZhou, 730030, China. zhangxb4@tom.com

ABSTRACT

Background: Advances in techniques have left very few indications for open surgical extraction of urinary stones currently. These advances notwithstanding, the search continues for medical approaches to urinary stone management. In this study, we perform an in vitro study analyzing the efficiency and prospect of two new complex solutions in urological calcium phosphate calculi dissolution.

Methods: Eighteen stones composed mainly of calcium phosphates were taken from patients who underwent kidney stone surgery. These stones were large enough (weight range 0.514-0.928 g) to be fragmented and matched equally into six groups. Chemolysis of phosphate stones was done with six different solvents and was repeated 3 times with 6 stones for each solution. At 24, 48 and 72 h, reduction in weight, percentage weight change, and dissolution rate; the dissolution rates at pH 5.0, 7.0 and 8.5 for each solution, using different cations (Na+, K+ or Ca2+), according to different dilutions (1:1, 1:2, 1:3, 1:4) of S1 and S2 were simultaneously determined.

Results: Calcium phosphate calculi were poorly dissolved by Phys and Art, and they had a low dissolution rate in pH 8.5 EDTA. The most effective solutions were S1, S2 and R, with 72 h mean dissolution rates: 5.75 +/- 0.44 mg/hr (S1), 5.2 +/- 0.63 mg/hr (S2), 4.55 +/- 0.46 mg/hr (R) (x +/- s, p < 0.01 R, S1 and S2 vs Phys, Art and EDTA; p < 0.05, S1 vs R, LSD-test). The mean percentage weight loss at 72 h was: 52.1 +/- 15.75 % (S1), 44.4 +/- 7.37 % (S2) and 40.5 +/- 3.67 % (R) ( x +/- s, p < 0.01 R, S1 and S2 vs Phys, Art and EDTA, LSD-test). Diluted twice, S1 and S2 had even better effectiveness than their initial solution. The additive of Na+, K+ or Ca2+ greatly reduced the dissolution rates of S1, S2.

Conclusion: Our data indicate that test solutions S1 and S2 are effective solvents in the chemolysis of calcium phosphate stones. At twice dilutions, these solutions are even more useful in the treatment of stone disease.

Show MeSH
Related in: MedlinePlus