Effects of urine dilution on quantity, size and aggregation of calcium oxalate crystals induced in vitro by an oxalate load

2005 ◽  
Vol 43 (6) ◽  
Author(s):  
Angela Guerra ◽  
Franca Allegri ◽  
Tiziana Meschi ◽  
Giuditta Adorni ◽  
Beatrice Prati ◽  
...  
Keyword(s):  
Calcium Oxalate ◽  
Renal Stones ◽  
Normal Subjects ◽  
Normal Male ◽  
Urinary Volume ◽  
Aggregation Index ◽  
Calcium Oxalate Dihydrate ◽  
Stone Formers ◽  
Crystalline Aggregates

AbstractIncreasing urinary volume is an important tool in the prevention of calcium renal stones. However, the mechanism of how it actually works is only partially understood. This study aimed at assessing how urine dilution affects urinary calcium oxalate crystallization. A total of 16 male idiopathic calcium oxalate (CaOx) stone-formers and 12 normal male subjects were studied and 4 h urine samples were taken twice, under low (undiluted urine) and high hydration conditions (diluted urine). An equal oxalate load (1.3mmol/L) was added to both types of urine and the crystallization parameters were assessed. In both stone-formers and normal subjects, the crystallization processes were significantly (p<0.05 or less) more marked in the undiluted urine than in the diluted urine in terms of: a) total quantity of calcium oxalate dihydrate (COD) and calcium oxalate monohydrate (COM) crystals; b) total quantity of crystalline aggregates; and c) aggregation index (i.e., ratio between the area occupied by crystalline aggregates and the area occupied by all the crystals present). The comparison between stone-formers and normal subjects showed that the greatest difference was for the size of COD crystals, which were larger in the urine of the stone-formers. A further important finding was an inverse relationship between changes in urinary volume and in the aggregation index (r=–0.53, p=0.004). In conclusion, urine dilution considerably reduces crystallization phenomena induced in vitro by an oxalate load in both calcium stone-formers and normal subjects.

The Effect of Ethane-1-Hydroxy-1,1-Diphosphonate (EHDP) on Calcium Oxalate Crystalluria in Recurrent Renal Stone-Formers

1974 ◽  
Vol 47 (1) ◽  
pp. 13-22 ◽  
Author(s):  
W. G. Robertson ◽  
M. Peacock ◽  
R. W. Marshall ◽  
F. Knowles
Keyword(s):  
Calcium Oxalate ◽  
Stone Formation ◽  
Basal Diet ◽  
Sodium Oxalate ◽  
Calcium Oxalate Crystals ◽  
Calcium Oxalate Dihydrate ◽  
Calcium Oxalate Stone ◽  
Oxalate Crystals ◽  
Stone Formers

1. The volume, size and type of calcium oxalate crystals excreted in the urine of a group of patients with recurrent ‘idiopathic’ stones were studied on a controlled basal diet, after an oral supplement of sodium oxalate and after oral administration of ethane-1-hydroxy-1,1-diphosphonate (EHDP) for 4 weeks. 2. Before administration of EHDP the stone-formers passed the large crystals and aggregates of calcium oxalate dihydrate characteristic of recurrent calcium oxalate stone-formers. For the same level of urine saturation and crystalluria EHDP caused a significant reduction in the proportion of large crystals and aggregates excreted. Studies by light-microscopy confirmed that EHDP caused a striking change in the size and habit of calcium oxalate crystals in some but not all of the urine samples examined. 3. The decrease in average crystal size during the administration of EHDP was attributed to the observed increase in the ability of urine to inhibit the growth and aggregation of calcium oxalate crystals as measured by a growth system in vitro. 4. The possible use of EHDP as a therapeutic agent in the treatment of calcium oxalate stone-formation is discussed.

Inhibition of calcium oxalate monohydrate crystal aggregation by urine proteins

1989 ◽  
Vol 257 (1) ◽  
pp. F99-F106 ◽  
Author(s):  
B. Hess ◽  
Y. Nakagawa ◽  
F. L. Coe
Keyword(s):  
Crystal Growth ◽  
Calcium Oxalate ◽  
Renal Stones ◽  
Calcium Oxalate Monohydrate ◽  
Assay Method ◽  
Crystal Aggregation ◽  
Stone Formers ◽  
Aggregation Inhibitors ◽  
Normal Urine

Normal urine inhibits both the growth and the aggregation of calcium oxalate monohydrate (COM) crystals but the molecules that inhibit aggregation are not well defined. We have developed a spectrophotometric assay method to measure the aggregation of COM crystals in vitro under conditions that avoid simultaneous crystal growth. At pH 7.2 and 90 mM NaCl, Tamm-Horsfall glycoprotein (THP) and nephrocalcin (NC), a major urinary inhibitor of COM crystal growth, inhibit COM crystal aggregation at concentrations as low as 2 X 10(-9) and 1 X 10(-8) M, respectively. When increasing NaCl to 270 mM or lowering pH to 5.7, inhibition by both glycoproteins, but more markedly by THP, is decreased. Urinary NC from calcium oxalate renal stone formers (SF NC) and NC isolated from calcium oxalate renal stones (stone NC) both inhibit COM crystal aggregation 10-fold less than NC from normal urine. Citrate is ineffective even at millimolar concentrations. Thus THP and NC are two major inhibitors of COM crystal aggregation in normal urine; SF NC and stone NC are defective aggregation inhibitors.

scholarly journals In Vivo Entombment of Bacteria and Fungi during Calcium Oxalate, Brushite and Struvite Urolithiasis

Kidney360 ◽  
2020 ◽  
pp. 10.34067/KID.0006942020
Author(s):  
Jessica J. Saw ◽  
Mayandi Sivaguru ◽  
Elena M. Wilson ◽  
Yiran Dong ◽  
Robert A. Sanford ◽  
...  
Keyword(s):  
Calcium Oxalate ◽  
Stone Formation ◽  
Human Kidney ◽  
Rrna Gene ◽  
Bacterial Cells ◽  
Stone Formers ◽  
Bacteria And Fungi ◽  
Struvite Stones

Background: Human kidney stones form via repeated events of mineral precipitation, partial dissolution and reprecipitation, which are directly analogous to similar processes in other natural and man-made environments where resident microbiomes strongly influence biomineralization. High-resolution microscopy and high-fidelity metagenomic (microscopy-to-omics) analyses, applicable to all forms of biomineralization, have been applied to assemble definitive evidence of in vivo microbiome entombment during urolithiasis. Methods: Stone fragments were collected from a randomly chosen cohort of 20 patients using standard percutaneous nephrolithotomy (PCNL). Fourier transform infrared (FTIR) spectroscopy indicated that 18 of these patients were calcium oxalate (CaOx) stone formers, while one patient each formed brushite and struvite stones. This apportionment is consistent with global stone mineralogy distributions. Stone fragments from 7 of these 20 patients (5 CaOx, 1 brushite and 1 struvite) were thin sectioned and analyzed using brightfield (BF), polarization (POL), confocal, superresolution autofluorescence (SRAF) and Raman techniques. DNA from remaining fragments, grouped according to each of the 20 patients, were analyzed with amplicon sequencing of 16S rRNA gene sequences (V1-V3, V3-V5) and internal transcribed spacer (ITS1, ITS2) regions. Results: Bulk entombed DNA was sequenced from stone fragments in 11 of the 18 CaOx patients, as well as the brushite and struvite patients. These analyses confirmed the presence of an entombed low-diversity community of bacteria and fungi, including Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, and Aspergillus niger. Bacterial cells ~1  µm in diameter were also optically observed to be entombed and well-preserved in amorphous hydroxyapatite spherules and fans of needle-like crystals of brushite and struvite. Conclusions: These results indicate a microbiome is entombed during in vivo CaOx stone formation. Similar processes are implied for brushite and struvite stones. This evidence lays the groundwork for future in vitro and in vivo experimentation to determine how the microbiome may actively and/or passively influence kidney stone biomineralization.

Relations between Oxalic Acid, Calcium, Magnesium and Creatinine Excretion in Normal Men and Male Patients with Calcium Oxalate Kidney Stones

1974 ◽  
Vol 46 (3) ◽  
pp. 357-367 ◽  
Author(s):  
A. Hodgkinson
Keyword(s):  
Calcium Oxalate ◽  
Normal Subjects ◽  
Calcium Excretion ◽  
Oxalate Excretion ◽  
Stone Formers ◽  
Calcium Magnesium ◽  
Male Patients ◽  
Calcium And Magnesium ◽  
Magnesium Excretion ◽  
Normal Men

1. The daily excretion of oxalate, calcium, magnesium and creatinine was determined in fifty-two normal men and sixty-five male patients with calcium oxalate-containing renal stones. 2. Direct relationships were found between calcium and oxalate excretion, magnesium and oxalate excretion and calcium and magnesium excretion in both normal subjects and stone-formers. The significance of these relationships is discussed. 3. The mean excretion of calcium and oxalate was significantly higher in the stone-formers, compared with the controls, both calcium and oxalate excretion being raised by about 20%. 4. The effect of oral ingestion of glucose and casein on the rate of excretion of calcium, magnesium, oxalate and phosphate was examined. Glucose increased the rate of calcium and magnesium excretion but had no effect on oxalate excretion and suppressed phosphate excretion. Casein also increased calcium excretion but had little or no effect on magnesium or oxalate excretion, and it increased phosphate excretion. 5. The association of high calcium excretion with high oxalate excretion, in both normal subjects and stone-formers, results in a high degree of supersaturation of the urine with respect to calcium oxalate. The implication of these findings with respect to the cause and treatment of calcium oxalate stones is discussed.

Glycosaminoglycan Content, Oxalate Self-Exchange and Protein Phosphorylation in Erythrocytes of Patients with ‘Idiopathic’ Calcium Oxalate Nephrolithiasis

1990 ◽  
Vol 79 (2) ◽  
pp. 113-116 ◽  
Author(s):  
Bruno Baggio ◽  
Giovanni Marzaro ◽  
Giovanni Gambaro ◽  
Francesco Marchini ◽  
Hibbard E. Williams ◽  
...  
Keyword(s):  
Membrane Protein ◽  
Calcium Oxalate ◽  
Protein Phosphorylation ◽  
Erythrocyte Membrane ◽  
Heparan Sulphate ◽  
Flux Rate ◽  
Control Subjects ◽  
Stone Formers ◽  
Membrane Phosphorylation

1. This study was performed to test the hypothesis that glycosaminoglycans may play an important role in the observed abnormalities in oxalate flux seen in patients with calcium oxalate nephrolithiasis. 2. Oxalate flux rate, erythrocyte membrane glycosaminoglycan content, membrane protein phosphorylation and effect of heparan sulphate on erythrocyte oxalate flux in vitro were studied in control subjects and patients with calcium oxalate nephrolithiasis. 3. In comparison with control subjects, renal stone-formers showed a significantly higher oxalate self-exchange, a lower erythrocyte membrane glycosaminoglycan content and a higher membrane phosphorylation rate. In stone-formers, erythrocyte glycosaminoglycan content correlated inversely with both oxalate flux rate and protein phosphorylation. In vitro, heparan sulphate promoted a significant fall in the rate of oxalate self-exchange. 4. These findings support the hypothesis that a lower erythrocyte membrane content of glycosaminoglycans enhances membrane protein phosphorylation, leading to an increased rate of transmembrane oxalate flux.

scholarly journals Citrate inhibits growth of residual fragments in an in vitro model of calcium oxalate renal stones

2004 ◽  
Vol 65 (5) ◽  
pp. 1724-1730 ◽  
Author(s):  
Karyee Chow ◽  
James Dixon ◽  
Sally Gilpin ◽  
John P. Kavanagh ◽  
Popduri N. Rao
Keyword(s):  
Calcium Oxalate ◽  
In Vitro Model ◽  
Renal Stones ◽  
Vitro Model ◽  
Residual Fragments

scholarly journals FRUIT PEEL EXTRACTS WITH POTENTIAL FOR DISSOLVING SIMULATED RENAL STONES IN IN VITRO CONDITIONS

2018 ◽  
Vol 10 (11) ◽  
pp. 74
Author(s):  
Karuna Sree Varicola ◽  
Amreen Siddiqua A. ◽  
Keerthi Dintyala ◽  
Gandhi Ventrapati
Keyword(s):  
Calcium Oxalate ◽  
Methanol Extract ◽  
Renal Stones ◽  
Punica Granatum ◽  
Precipitation Method ◽  
Malus Pumila ◽  
Fruit Peel ◽  
Standard Drug ◽  
Musa Sapientum

Objective: To evaluate the antiurolithiatic activity of selected fruit peels on simulated renal stones in in vitro conditions.Methods: Simulated renal stones were prepared by homogenous precipitation method. The criterion selected was to estimate the amount of calcium oxalate remaining in the semi-permeable membranes by Kramer and Tisdal method with slight modification. A suitable media was provided by TRIS buffer.Results: The crude methanol extract of Musa sapientum exhibited highest dissolution of calcium oxalate ie.9.15 mg and the percent dissolved was found to be 91.5% in comparison to Malus pumila methanol extract which dissolved 8.96 mg (89.6%) and Punica granatum methanol extract which dissolved 8.0 mg (80.0%). Its activity was comparable with that of standard drug Tamsulosin hydrochloride (400 mg) with a percentage dissolved of about 90.5%.Conclusion: Experimental evidence showed that methanol and aqueous fruit peel extracts of Musa sapientum, Malus pumila, and Punica granatum possess potential antiurolithiatic activity. Their effect is found to be significant and the extracts can be used in the treatment of lithiasis.

Relationships between Calcium and Oxalic Acid Intake in the Diet and Their Excretion in the Urine of Normal and Renal-Stone-Forming Subjects

1972 ◽  
Vol 43 (1) ◽  
pp. 91-99 ◽  
Author(s):  
R. W. Marshall ◽  
M. Cochran ◽  
A. Hodgkinson
Keyword(s):  
Oxalic Acid ◽  
Calcium Oxalate ◽  
Calcium Intake ◽  
Renal Stones ◽  
Normal Subjects ◽  
Calcium Excretion ◽  
Oxalate Excretion ◽  
Low Calcium Diet ◽  
Normal Men ◽  
Dietary Oxalate

1. The short-term effects of different intakes of calcium and oxalic acid on the urinary excretion of these substances was studied in eight normal men and eight men with a history of calcium-containing renal stones. 2. The effect of dietary oxalate on urine oxalate depended partly upon the calcium intake. Thus, on a normal calcium intake an increase in oxalate intake caused an increase in oxalate excretion that corresponded to 3·6% of the additional dietary oxalate; on a low calcium diet, however, the increase corresponded to 8·1%. 3. A decrease in daily calcium intake from 1000 to 250 mg caused a fall in calcium excretion averaging 150 mg/day in the patients and 60 mg/day in the controls but this was accompanied by average rises of 10 and 7 mg/day respectively in oxalate excretion, with the result that the calcium oxalate activity products remained almost unchanged. 4. A decrease in oxalate as well as calcium intake resulted in a fall in calcium excretion that was not accompanied by a rise in oxalate excretion, and there was a statistically significant fall in the calcium oxalate activity product in both the patients and normal subjects.

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