scholarly journals Composition and Morphology of Nanocrystals in Urines of Lithogenic Patients and Healthy Persons

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Bao-Song Gui ◽  
Rong Xie ◽  
Xiu-Qiong Yao ◽  
Mei-Ru Li ◽  
Jian-Ming Ouyang

The composition and morphology of nanocrystals in urines of healthy persons and lithogenic patients were comparatively investigated by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was shown that the main composition of urinary nanocrystals in healthy persons were calcium oxalate dihydrate (COD), uric acid, and ammonium magnesium phosphate (struvite). However, the main compositions of urinary nanocrystals in lithogenic patients were struvite,β-tricalcium phosphate, uric acid, COD, and calcium oxalate monohydrate (COM). According to the XRD data, the size of nanocrystals was calculated to be23∼72 nm in healthy urine and12∼118 nm in lithogenic urine by Scherer formula. TEM results showed that the nanocrystals in healthy urine were dispersive and uniform with a mean size of about 38 nm. In contrast, the nanocrystals in lithogenic urine were much aggregated with a mean size of about 55 nm. The results in this work indicated that the urinary stone formation may be prevented by diminishing the aggregation and the size differentiation of urinary nanocrystals by physical or chemical methods.

1990 ◽  
Vol 79 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Phulwinder K. Grover ◽  
Rosemary L. Ryall ◽  
Villis R. Marshall

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.


2020 ◽  
Author(s):  
Alberto Trinchieri ◽  
Alessandro Maletta ◽  
Giovanni Simonelli ◽  
Luca Boeri ◽  
Elisa De Lorenzis ◽  
...  

Abstract Introduction: An increase of the frequency of uric acid urinary stones compared to calcium-containing ones has been recently described. This study was aimed at assessing the frequency of different types of urinary stones in the population of northern Italy in the period 2016-18 compared to 2001-2003. Materials and Methods: Analyses by infrared spectroscopy of 1007 stones endoscopically removed at two institutions in the area of Milan (Northern Italy) were retrospectively considered. Stones were classified as calcium oxalate monohydrate (COM) and dihydrate (COD), mixed uric acid/calcium oxalate (UC); uric acid (UA), struvite (ST); apatite (CAP); mixed calcium oxalate / apatite (CAPOX); others. The patients were divided into two groups: 2001-2003 and 2016-2018. The average temperature values of the region over the two time periods were obtained by the national statistical institute. Results: The average age of the 2001-2003 group (45.8+/-15.4 years) was significantly lower than the average age of the 2016-18 group (57.9+/-14.8) (0.000). M / F ratio was similar in the two groups: 119 / 69 (1:0.58) in 2001-2003 MI and 527 / 292 (1:0.55) in 2016-18 (p = 0.862). COM stones tended to more frequent in 2016-18 group than in 2001-03. COD stones were significantly more frequent in 2001-03 than in 2016-18. ST stone frequency was increased from 2001-03 to 2016-18. No increase of uric acid containing stones was observed in 2016-18. Results were confirmed after adjustment by age. Averages annual regional temperatures increased from 14° C to 15.4° C during the two observation periods. Conclusions: No increase of UA stones was observed, probably due to the limited impact of the global warming in our temperate climate.


2020 ◽  
Author(s):  
Alberto Trinchieri ◽  
Alessandro Maletta ◽  
Giovanni Simonelli ◽  
Luca Boeri ◽  
Elisa De Lorenzis ◽  
...  

Abstract Background: An increase of the frequency of uric acid urinary stones compared to calcium-containing ones has been recently described. This study was aimed at assessing the frequency of different types of urinary stones in the population of northern Italy in the period 2016-18 compared to 2001-2003.Methods: Analyses by infrared spectroscopy of 1007 stones endoscopically removed at two institutions in the area of Milan (Northern Italy) were retrospectively considered. Stones were classified as calcium oxalate monohydrate (COM) and dihydrate (COD), mixed uric acid/calcium oxalate (UC); uric acid (UA), struvite (ST); apatite (CAP); mixed calcium oxalate / apatite (CAPOX); others. The patients were divided into two groups: 2001-2003 and 2016-2018. The average temperature values of the region over the two time periods were obtained by the national statistical institute.Results: The average age of the 2001-2003 group (45.8+/-15.4 years) was significantly lower than the average age of the 2016-18 group (57.9+/-14.8) (0.000). M / F ratio was similar in the two groups: 119 / 69 (1:0.58) in 2001-2003 and 527 / 292 (1:0.55) in 2016-18 (p = 0.862). COM stones tended to more frequent in 2016-18 group than in 2001-03. COD stones were significantly more frequent in 2001-03 than in 2016-18. ST stone frequency was increased from 2001-03 to 2016-18. No increase of uric acid containing stones was observed in 2016-18. Results were confirmed after adjustment by age. Averages annual regional temperatures increased from 14° C to 15.4° C during the two observation periods.Conclusions: No increase of UA stones was observed, probably due to the limited impact of the global warming in our temperate climate.


2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Alberto Trinchieri ◽  
Alessandro Maletta ◽  
Giovanni Simonelli ◽  
Luca Boeri ◽  
Elisa De Lorenzis ◽  
...  

Abstract Background An increase of the frequency of uric acid urinary stones compared to calcium-containing ones has been recently described. This study was aimed at assessing the frequency of different types of urinary stones in the population of northern Italy in the period 2016–18 compared to 2001–2003. Methods Analyses by infrared spectroscopy of 1007 stones endoscopically removed at two institutions in the area of Milan (Northern Italy) were retrospectively considered. Stones were classified as calcium oxalate monohydrate (COM) and dihydrate (COD), mixed uric acid/calcium oxalate (UC); uric acid (UA), struvite (ST); apatite (CAP); mixed calcium oxalate / apatite (CAPOX); others. The patients were divided into two groups: 2001–2003 and 2016–2018. The average temperature values of the region over the two time periods were obtained by the national statistical institute. Results The average age of the 2001–2003 group (45.8+/− 15.4 years) was significantly lower than the average age of the 2016–18 group (57.9+/− 14.8) (0.000). M / F ratio was similar in the two groups: 119 / 69 (1,0.58) in 2001–2003 and 527 / 292 (1,0.55) in 2016–18 (p = 0.862). COM stones tended to more frequent in 2016–18 group than in 2001–03. COD stones were significantly more frequent in 2001–03 than in 2016–18. ST stone frequency was increased from 2001 to 03 to 2016–18. No increase of uric acid containing stones was observed in 2016–18. Results were confirmed after adjustment by age. Averages annual regional temperatures increased from 14 °C to 15.4 °C during the two observation periods. Conclusions No increase of UA stones was observed, probably due to the limited impact of the global warming in our temperate climate.


2018 ◽  
Vol 37 (12) ◽  
pp. 717-723 ◽  
Author(s):  
Kiyoko Kaneko ◽  
Mizuho Kabeya ◽  
Hirokazu Kondo ◽  
Tomoko Fukuuchi ◽  
Noriko Yamaoka ◽  
...  

2014 ◽  
Vol 952 ◽  
pp. 38-42
Author(s):  
Lan Qing Deng ◽  
Jun Fa Xue ◽  
Cai Yan Tang ◽  
Yu Shan Xie ◽  
Jian Ming Ouyang

The influence of urinary macromolecule chondroitin sulfate A (C4S) on Zeta potential, aggregation and sedimentation of calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) nanocrystallites with a diameter of about 50 nm were investigated using nanoparticle size Zeta potential analyzer and transmission electron microscope. C4S could increase the absolute value of Zeta potential on surface of nanoCOM and nanoCOD crystallites by adsorbing on crystal surface, it led an increase of the electrostatic repulsion force between the crystallites, so the aggregation and sedimentation of these crystallites were inhibited, and the stability of the suspension of nanoCOM and nanoCOD was improved. In conclusion, C4S could inhibit the formation of CaOxa stones。


2018 ◽  
Author(s):  
José Luiz Nishiura ◽  
Ita Pfeferman Heilberg

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.


2001 ◽  
Vol 101 (2) ◽  
pp. 159-168 ◽  
Author(s):  
David E. FLEMING ◽  
Wilhelm VAN BRONSWIJK ◽  
Rosemary Lyons RYALL

To assess the binding of individual amino acids to the principal calcium minerals found in human kidney stones, the adsorption of 20 amino acids on to calcium oxalate monohydrate, CaHPO4.2H2O, Ca3(PO4)2 and Ca5(PO4)3OH crystals was determined over the physiological urinary pH range (pH 5–8) in aqueous solutions. All amino acids adsorbed most strongly at pH 5, and this decreased in all cases as the pH was increased. The amino acids which adsorbed most strongly were aspartic acid, glutamic acid and γ-carboxyglutamic acid, with the last displaying the strongest affinity. All amino acids bound more avidly to calcium oxalate monohydrate than to any of the phosphate minerals. Adsorption on to CaHPO4.2H2O was generally higher than for Ca3(PO4)2 and Ca5(PO4)3OH, for which all amino acids, with the exception of γ-carboxyglutamic acid, had only a weak affinity. The binding affinity of these acids is thought to be due to their zwitterions being able to adopt conformations in which two carboxyl groups, and possibly the amino group, can interact with the mineral surface without further rotation. The strong binding affinity of di-and tri-carboxylic acids for calcium stone minerals indicates that proteins rich in these amino acids are more likely to play a functional role in stone pathogenesis than those possessing only a few such residues. These findings, as well as the preferential adsorption of the amino acids for calcium oxalate monohydrate rather than calcium phosphate minerals, have ramifications for research aimed at discovering the true role of proteins in stone formation and for potential application in the design of synthetic peptides for use in stone therapy.


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