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Stone Formation (stone + formation)
Kinds of Stone Formation Selected AbstractsVacuolar H+ -ATPase expression is increased in acid-secreting intercalated cells in kidneys of rats with hypercalcaemia-induced alkalosisACTA PHYSIOLOGICA, Issue 4 2007W. Wang Abstract Aims:, Hypercalcaemia is known to be associated with systemic metabolic alkalosis, although the underlying mechanism is uncertain. Therefore, we aimed to examine whether hypercalcaemia was associated with changes in the expression of acid,base transporters in the kidney. Methods:, Rats were infused with human parathyroid hormone (PTH, 15 ,g kg,1 day,1), or vehicle for 48 h using osmotic minipumps. Results:, The rats treated with PTH developed hypercalcaemia and exhibited metabolic alkalosis (arterial HCO: 31.1 ± 0.8 vs. 28.1 ± 0.8 mmol L,1 in controls, P < 0.05, n = 6), whereas the urine pH of 6.85 ± 0.1 was significantly decreased compared with the pH of 7.38 ± 0.1 in controls (P < 0.05, n = 12). The observed alkalosis was associated with a significantly increased expression of the B1-subunit of the H+ -ATPase in kidney inner medulla (IM, 233 ± 45% of the control level). In contrast, electroneutral Na+ -HCO cotransporter NBCn1 and Cl,/HCO anion exchanger AE2 expression was markedly reduced in the inner stripe of the outer medulla (to 26 ± 9% and 65 ± 6%, respectively). These findings were verified by immunohistochemistry. Conclusions:, (1) hypercalcaemia-induced metabolic alkalosis was associated with increased urinary excretion of H+; (2) the increased H+ -ATPase expression in IM may partly explain the enhanced urinary acidification, which is speculated to prevent stone formation because of hypercalciuria and (3) the decreased expression of outer medullary AE2 suggests a compensatory reduction of the transepithelial bicarbonate transport. [source] The prothrombin gene is expressed in the rat kidneyFEBS JOURNAL, Issue 1 2000Implications for urolithiasis research There is considerable interest in determining the role of prothrombin fragments, especially urinary prothrombin fragment 1 (UPTF1), in the pathogenesis of calcium oxalate (CaOx) urinary calculi. This fragment is present in abundance in the matrix of CaOx crystals generated in human urine in vitro and has also been detected in human urinary stones containing calcium. More recently, prothrombin gene expression has been reported in the human kidney. However, studies examining the renal biosynthesis of prothrombin or perhaps only its fragments during experimental lithogenesis, and in consequence, the role of UPTF1 in stone formation, cannot be carried out in humans. The aim of this investigation therefore was to determine whether prothrombin gene expression is present in the rat kidney. Total RNA was isolated from the kidneys and livers of 12 rats. Using reverse transcriptase PCR, mRNAs corresponding to the thrombin and fragment 1 + 2 (F1+2) regions of prothrombin were analysed by agarose gel electrophoresis. The expression of glyceraldehyde 3-phosphate dehydrogenase was also examined to determine whether the quality of the tissue mRNAs was adequate for analyses. The amplified products were identified by sequence analysis. All kidneys displayed evidence of expression of the thrombin and F1+2 domains of the prothrombin gene. Furthermore, the sequences of these PCR-derived products from kidney were identical to those from liver. This suggests that the prothrombins secreted by these two organs are identical. The fact that prothrombin biosynthesis occurs in both the human and rat kidney presents an opportunity for using established rat models of stone disease to evaluate the influence of lithogenic conditions on prothrombin gene expression, and the potential role of UPTF1 in vivo. [source] Serum Uric Acid and Lipid Levels While Taking Topiramate for MigraineHEADACHE, Issue 7 2008Abdulkadir Koçer MD Objective., Topiramate (TPM) therapies for epilepsy or migraine are long-time therapies with unknown mechanisms and special side effects. TPM influences cholesterol (TC) and lipoprotein serum levels. In addition, TPM may cause uric acid (UA) stone formation. Material and Methods., Serum UA, TC, and triglyceride (TG) levels were measured in 53 migraine patients receiving TPM and in 44 age- and sex-matched controls. Compared with controls, patients on TPM showed significantly higher UA and nonsignificantly higher TC and TG values. We recorded pre- and posttreatment levels of UA, TC, and TG levels in 23 patients. Results., We found increased serum levels of UA with TPM use (P < .01). There was a significant and positive correlation between serum UA levels and male gender (P < .01). The changes in serum UA levels before and after TPM treatment differed significantly (P < .01). Conclusion., Our results suggest a need for monitoring serum UA levels in patients receiving TPM. We should perhaps prescribe a low-UA diet and advice to drink much more water in these patients. [source] Recurrent bile duct stones after transduodenal sphincteroplastyHPB, Issue 2 2002SMG Kibria Background Transduodenal sphincteroplasty (TDS) offers permanent prophylaxis against further stones in the common bile duct (CBD) by allowing continuous free efflux of bile from the papilla. Patients and resultsIn a personal series of 267 consecutive operations, four patients underwent further treatment for recurrent CBD stones during a median follow-up of 12 years. Three of them received Roux-en-Y biliary diversion and had no further symptoms; the fourth patient remains well four years after endoscopic extraction of stones. Discussion Recurrent stone formation is rare after an adequate TDS and probably reflects retained food debris within the CBD. Initial treatment may be endoscopic, but biliary diversion is needed for those with recurrent symptoms. [source] Mechanism of calcium oxalate renal stone formation and renal tubular cell injuryINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2008Masao Tsujihata Abstract: Formation of calcium oxalate stones tends to increase with age and begins from the attachment of a crystal formed in the cavity of renal tubules to the surface of renal tubular epithelial cells. Though most of the crystals formed in the cavity of renal tubules are discharged as is in the urine, in healthy people, crystals that attach to the surface of renal tubular epithelial cells are thought to be digested by macrophages and/or lysosomes inside of cells. However, in individuals with hyperoxaluria or crystal urine, renal tubular cells are injured and crystals easily become attached to them. Various factors are thought to be involved in renal tubular cell injury. Crystals attached to the surface of renal tubular cells are taken into the cells (crystal,cell interaction). And then the crystal and crystal aggregates grow, and finally a stone is formed. [source] Bladder wall grafting in rats using salt-modified and collagen-coated polycaprolactone scaffolds: Preliminary reportINTERNATIONAL JOURNAL OF UROLOGY, Issue 10 2007Dah-Shyong Yu Aim: A rat model was used for the evaluation of collagen-coated and salt-modified polycaprolactone (PCL) scaffolds for bladder grafting after hemicystectomy. Methods: SD rats underwent partial cystectomy and cystoplasty with collagen-coated and salt-modified polycaprolactone scaffolds. The grafts of the regenerated bladder wall were harvested at different intervals and tissue regeneration was evaluated microscopically. Anatomic and functional characters were evaluated by cystography and urodynamics. Results: At harvesting, after 1 and 2 months, we found good preservation of the bladder shape and volume in all 16 rats receiving PCL cystorrhaphy. No stone formation was observed. Good epithelialization and ingrowth of smooth muscle cells were seen after 2 months grafting. Collagen-coated PCL scaffolds showed considerable encrustation, which appeared to be absorbed and disappear with time. The cystographic and urodynamic examinations revealed intact contour and a well-accommodated bladder with reservoir volume and contractility. Conclusions: In the rat model, we have successfully demonstrated the applicability of collagen coated and salt-modified PCL in reconstruction of the partial cystectomized bladder. [source] Chronic acid ingestion promotes renal stone formation in rats treated with vitamin D3INTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2007Naohiko Okamoto Objective: Although hypercalciuria, a well-established adverse effect of vitamin D3, can be a risk factor of renal stone formation, the risk of nephrolithiasis has not been well defined. The consumption of a diet high in acid precursors is often cited as a risk factor for the development of calcium-based kidney stones. In the present study, we investigated the effect of chronic acid ingestion on kidney stone formation in rats treated with calcitriol (1,25[OH]2 D3). Methods: Control rats (C-C), calcitriol-treated rats (C-V; three treatments of 0.5 µg of calcitriol per week) and acid-ingested (water containing 0.21 mol/L NH4Cl), calcitriol-treated (three treatments of 0.5 µg of calcitriol per week) rats (A-V) were fed in metabolic cages. After 1 month, urine, blood, kidney and bone samples were analyzed. Results: The A-V rats exhibited elevated serum calcium concentrations, urinary calcium and phosphate excretion, urinary type I collagen cross-linked N-peptide (NTx)/creatinine values, mRNA expression of osteopontin in the kidney, and renal calcium contents as well as decreased bone mineral densities, compared with the C-C and C-V rats. Urinary citrate excretion was lower and NaDC-1 mRNA expression in the kidney was higher in the A-V rats than in the C-C and C-V rats. Calcium phosphate kidney stones were found in the A-V rats. Conclusions: The ingestion of NH4Cl, an acid precursor, promotes calcium phosphate kidney stone formation in calcitriol-treated rats. The chronic intake of a diet rich in acid precursors may be a risk factor for the development of kidney stones in subjects who are being treated with calcitriol. [source] Kidney stone disease and risk factors for coronary heart diseaseINTERNATIONAL JOURNAL OF UROLOGY, Issue 10 2005SATOSHI HAMANO Abstract Background:, We conducted a case-control study to examine the impact of coronal heart disease (CHD) risk factors on calcium oxalate (CaOX) stone formation. Methods:, Variables included body mass index (BMI), current alcohol use, smoking habit, hypertension, hypercholesterolemia, diabetes mellitus, and hyperuricemia. Data suf,cient for analysis were obtained for 181 CaOX stone formers and 187 controls. Results:, Seven of 181 stone formers (3.9%) had a history of CHD compared with none of 187 control subjects (P = 0.007). In univariate logistic regression analysis, smoking habit (OR 4.41, 95% CI 2.85,6.84, P < 0.0001), hypertension (OR 4.24, 95% CI 2.61,6.91, P < 0.0001), hypercholesterolemia (OR 3.03, 95% CI 1.77,5.20, P < 0.0001) and BMI (OR 1.10, 95% CI 1.04,1.17, P = 0.007) reached statistical signi,cance. In a multivariate logistic regression analysis, smoking habit (OR 4.29, 95% CI 2.68,6.86, P < 0.0001), hypertension (OR 3.57, 95% CI 2.11,6.07, P < 0.0001), and hypercholesterolemia (OR 2.74, 95% CI 1.51,5.00, P = 0.001) reached statistical signi,cance, while BMI (OR 1.06, 95% CI 0.99,1.12, P = 0.09) did not. Conclusions:, CaOX stone formers are signi,cantly associated with several CHD risk factors, including smoking habit, hypertension, hypercholesterolemia, and obesity. [source] The relationship of magnesium intake to serum and urinary calcium and magnesium levels in Trinidadian stone formersINTERNATIONAL JOURNAL OF UROLOGY, Issue 3 2005TREVOR I ANATOL Abstract, Background:, The present study was undertaken to investigate the relationship between the dietary intake of magnesium and the serum and urinary levels of calcium and magnesium in a group of Trinidadian stone formers. Methods:, A group of 102 confirmed stone formers presenting to urological clinics were interviewed using a questionnaire designed to obtain a semi-quantitative estimate of their oral magnesium intake. Patients were invited to give blood samples for serum calcium and magnesium levels and to provide 24-h urine specimens for the measurement of urinary levels of these minerals, as well as total urinary volumes. A group of 102 controls was subjected to a similar interview and blood and urinary testing. Chi-square tests and Student's t -tests were used to examine group demographic differences. The Mann,Whitney test investigated differences in biochemical indices. Binary logistic regression was used to identify predictors of stone formation. Results:, Blood samples were obtained from 60 patients and 98 controls. Urine samples were returned by 34 patients and 97 controls. Only 10 stones were retrieved from patients. Patients had a significantly lower magnesium intake, but higher median serum and urinary calcium levels, and higher serum calcium to magnesium ratios than controls. Independent variables capable of predicting stone formation included total magnesium intake and serum and urinary calcium levels. Conclusions:, Increased serum and urinary calcium levels, calcium to magnesium ratios, and a low magnesium intake were predictive of stone formation in this Trinidadian population. [source] Association of absence of intestinal oxalate degrading bacteria with urinary calcium oxalate stone formationINTERNATIONAL JOURNAL OF UROLOGY, Issue 6 2003KAZUO MIKAMI Abstract Aim: Urinary concentration of oxalate is considered an important factor in the formation of renal stones. Dietary oxalate is a major contributor to urinary oxalate excretion in most individuals. Furthermore, oxalate degrading bacteria have been isolated from human feces. We investigated the significance of oxalate degrading bacteria for urinary oxalate excretion and urinary stone formation. Methods: Twenty-two known calcium oxalate stone-forming patients (stone formers) and 34 healthy volunteers (non-stone formers) were included in the study. Stool specimens were inoculated into pepton yeast glucose (PYG) medium supplemented with oxalate under anaerobic condition at 37 C for one week. After the incubation period, each colony was checked for the loss of oxalate from the culture medium. A 24-h urine sample was collected in 43 individuals and analyzed for oxalate excretion. Results: Twenty-eight of 34 (82%) healthy volunteers and 10 of 22 (45%) calcium oxalate stone formers were colonized with oxalate degrading bacteria. Calcium oxalate stone formers were more frequently free of oxalate degrading bacteria (P < 0.01). Urinary excretion of oxalate in those with oxalate degrading bacteria was significantly less than in those without oxalate degrading bacteria (P < 0.05). Hyperoxaluria (> 40 mg/day) was found in four of 27 individuals (15%) with oxalate degrading bacteria compared to seven of 16 (44%) without oxalate degrading bacteria (P < 0.05), suggesting an association between the absence of oxalate degrading bacteria and the presence of hyperoxaluria. Conclusion: The absence of oxalate degrading bacteria in the gut could promote the absorption of oxalate, thereby increasing the level of urinary oxalate excretion. The absence of oxalate degrading bacteria from the gut appears to be a risk factor for the presence of absorptive hyperoxaluria and an increased likelihood of urolithiasis. [source] Impact of citrate therapy on the circadian rhythm of urinary magnesium ammonium phosphate saturation in normal individualsINTERNATIONAL JOURNAL OF UROLOGY, Issue 8 2000Yoshihide Ogawa Abstract Background: Alkaline citrate has been used widely in the prevention of stone formation. However, the risk of struvite stone during the alkalinizing therapy has not been adequately studied in terms of magnesium ammonium phosphate saturation. Methods: The circadian rhythm of the urinary saturation of magnesium ammonium phosphate was estimated by using the differential Gibbs' free energy values of magnesium ammonium phosphate before and during 5 days of treatment with sodium,potassium citrate (1 g t.i.d., 1 g q.i.d. or 3 g t.i.d.) in five healthy male volunteers. Results: The magnesium ammonium phosphate saturation varied during the day, peaking far below the solubility product between 08.00 and 10.30 h and between 13.00 and 18.00 h. The mean peak levels were increased by each treatment regimen in comparison with the control day. The mean increase on day 1 was significant between 10.30 and 23.00 h with the 3 g t.i.d. regimen, but the mean saturation still remained below the solubility product throughout the day. Conclusions: The urinary magnesium ammonium phosphate saturation appeared hard to exceed the solubility product with a high dose of alkaline citrate. [source] Protein profiling of organic stone matrix and urine from dogs with urolithiasisJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5-6 2006S. Forterre Summary Two-thirds of the organic matrix in urinary stones consists of proteins. Their relationship to calculogenesis remains controversial with regard to their effect as inhibitors or promoters during stone formation. The purpose of the present study was to determine the differences in peptide and protein pattern between the urine of stone formers (n = 23) and control dogs (n = 12), as well as between organic matrix of different urinary stones (struvite n = 11, calcium oxalate n = 8, uric acid n = 4) using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. Specific differences in protein and peptide profiles were found in the organic matrix of different mineral compositions. Characteristic differences were also found in urinary peptide and protein pattern especially in molecular masses below 20 kDa between affected and healthy dogs. Based on the obtained molecular masses they were in some cases tentatively identified as proteins that are known to be involved in stone formation in humans. The study shows that in dogs, specific-urinary peptides and proteins might be associated with urolithiasis. It indicates the importance to further characterize those proteins for possible diagnostic purposes in prognosis and therapy. [source] Risk factor analysis and relative supersaturation as tools for identifying calcium oxalate stone-forming dogsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 11 2003A. E. Stevenson Twenty-four hour urine samples were collected from 17 calcium oxalate (CaOx) stone-forming (SF) dogs and 17 normal (N), age-, breed- and sex-matched dogs. Urinary CaOx relative supersaturation (RSS) was calculated and found to be significantly higher in the SF group than the N group. RSS measurement is not readily applicable to veterinary practice; thus, alternatives were explored. Discriminant analysis failed to identify key factors differentiating most SF from N dogs. Urinary calcium, oxalate and uric acid, which differed between the SF and N animals, were combined into a measure of relative probability of CaOx stone formation (PSF) to establish whether this approach could be used to assess the risk of CaOx stone formation in dogs. Although there was good correlation between the techniques, RSS more clearly discriminated between SF and N dogs. These data suggest that neither PSF nor discriminant analysis is preferable to RSS for assessing the risk of CaOx stone formation in dogs. [source] Phytate in foods and significance for humans: Food sources, intake, processing, bioavailability, protective role and analysisMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue S2 2009Ulrich Schlemmer Abstract The article gives an overview of phytic acid in food and of its significance for human nutrition. It summarises phytate sources in foods and discusses problems of phytic acid/phytate contents of food tables. Data on phytic acid intake are evaluated and daily phytic acid intake depending on food habits is assessed. Degradation of phytate during gastro-intestinal passage is summarised, the mechanism of phytate interacting with minerals and trace elements in the gastro-intestinal chyme described and the pathway of inositol phosphate hydrolysis in the gut presented. The present knowledge of phytate absorption is summarised and discussed. Effects of phytate on mineral and trace element bioavailability are reported and phytate degradation during processing and storage is described. Beneficial activities of dietary phytate such as its effects on calcification and kidney stone formation and on lowering blood glucose and lipids are reported. The antioxidative property of phytic acid and its potentional anticancerogenic activities are briefly surveyed. Development of the analysis of phytic acid and other inositol phosphates is described, problems of inositol phosphate determination and detection discussed and the need for standardisation of phytic acid analysis in foods argued. [source] Dietary Therapy in Idiopathic NephrolithiasisNUTRITION REVIEWS, Issue 7 2006Loris Borghi MD Like other diseases striking predominantly the affluent societies, idiopathic nephrolithiasis is increasing in rich countries and appears to be closely related to dietary habits. In this review we summarize the latest evidence about the efficacy of dietary treatment for idiopathic calcium and uric acid stones, dealing especially with its effect on the urinary stone risk factors, stone recurrences, and clinical limitations. After a short introduction on epidemiology and pathogene-sis, we review the role of the most important foods and nutrients in stone formation and protection: water and other fluids, proteins, carbohydrates, fats, salt, milk and dairy products, fruits and vegetables, and vitamins. The final part of the paper will provide practical guidelines for pursuing an anti-lithogenic diet in idiopathic calcium and uric acid stones. [source] Prophylaxis effect of Trigonella foenum graecum L. seeds on renal stone formation in ratsPHYTOTHERAPY RESEARCH, Issue 10 2007Amine Laroubi Abstract Despite considerable progress in medical therapy, there is no satisfactory drug to treat kidney stones. Therefore, the current study aimed to look for an alternative by using Trigonella foenum graecum (Tfg) on nephrolithiasic rats as a preventive agent against the development of kidney stones, which is commonly used in Morocco as a phytotherapeutic agent. The inhibitory effect of the aqueous extract of Tfg seeds was examined on the formation of calcium oxalate renal stones induced by ethylene glycol (EG) with ammonium chloride. At the end of the experiment all kidneys were removed and examined microscopically for possible crystal/stone locations and the total calcium amount in the renal tissue was evaluated. The blood was recovered to determine the levels of calcium, phosphorus, creatinine and urea. The results showed that the amount of calcification in the kidneys and the total calcium amount of the renal tissue in rats treated with Tfg were significantly reduced compared with the untreated group. Consequently, Tfg may be a useful agent in the treatment of patients with calcic urolithiasis. Copyright © 2007 John Wiley & Sons, Ltd. [source] Evaluation of the effect of triterpenes on urinary risk factors of stone formation in pyridoxine deficient hyperoxaluric ratsPHYTOTHERAPY RESEARCH, Issue 6 2002Lakshminarasimhan Vidya Abstract Investigations were carried out to evaluate the efficacy of the pentacyclic triterpene, lupeol and its ester, lupeol linoleate, against calcium oxalate urolithiasis in rats. Administration of a pyridoxine deficient diet containing 3% glycollic acid for 21 days led to increased excretion of stone forming constituents such as calcium, oxalate and uric acid. Crystal deposition and subsequent renal tubular damage resulted in increased excretion of the tubular enzymes alkaline phosphatase, lactate dehydrogenase, , glutamyl transferase, , glucuronidase and N -acetyl glucosaminidase along with reduced fibrinolytic enzymes. A reduction in the urinary inhibitory factors magnesium and glycosaminoglycans was also observed. Treatment with lupeol and lupeol linoleate reduced the extent of tubular damage as evidenced from reduced enzymuria and minimized the excretion of stone forming constituents. Copyright © 2002 John Wiley & Sons, Ltd. [source] Heterogeneous Disease Modeling for Hardy-Weinberg Disequilibrium in Case-Control Studies: Application to Renal Stones and Calcium-Sensing Receptor PolymorphismsANNALS OF HUMAN GENETICS, Issue 2 2009D. C. Hamilton Summary Renal stone formation due to hypercalciuria is a relatively common disorder with clear evidence for genetic predisposition, but cryptic phenotypic heterogeneity has hampered identification of candidate genes. The R990G single-nucleotide polymorphism (SNP) of the calcium sensing receptor (CASR) gene has been associated with hypercalciuria in stone formers and shows the appropriate functional phenotype in cell culture. In our preliminary association analysis of a case-control cohort, however, we observed significant Hardy-Weinberg disequilibrium (HWD) for the cases (n= 223), but not controls (n= 676) at the R990G locus, pointing us toward the general disease model incorporating HWD. Because there is an adjacent CASR SNP, A986S, which is in negative linkage disequilibrium with R990G, we extended the general disease model to enable testing of a two-site hypothesis. In our data set, there is no lack of fit (P= .345) for the single-locus model for the R990G genotype, and likelihood ratio testing favors a recessive effect with an eight-fold increase in risk (P < .001) for GG homozygotes, relative to wild-type, based on a population prevalence of 2%. Addition of the A986S genotype provides no additional information either by itself or when included in our two-site model. [source] Variation in the incidence of and risk factors for the development of nephrolithiasis after radical or partial nephrectomyBJU INTERNATIONAL, Issue 8 2010Aditya Bagrodia Study Type , Prevalence (retrospective cohort) Level of Evidence 2b OBJECTIVE To examine incidence of and risk factors for the development of nephrolithiasis in patients treated with radical nephrectomy (RN) or partial nephrectomy (nephron-sparing surgery, NSS). PATIENTS AND METHODS The study comprised a single-centre review of 749 patients treated with RN or NSS from August 1987 to June 2006. Demographics, medical and stone history, metabolic variables and postoperative stone events were recorded. Data were analysed within subgroups based on treatment (RN vs NSS). Multivariate analysis was used to identify risk factors for postoperative stone formation. RESULTS In all, 499 patients had RN and 250 had NSS (mean age 57.9 years; mean follow-up 6.3 years). There were no significant differences in their demographic factors, but tumours were significantly larger in RN (P < 0.001). There was no significant difference in preoperative urinary pH < 6.0 or stone history. Significantly fewer patients after NSS than RN formed calculi (NSS 1.6% vs RN 8.4%, P < 0.001), developed hypobicarbonataemia (NSS 7.2% vs RN 12.8%, P= 0.020), and a urinary pH of <6.0 (NSS 11.2% vs RN 19.4%, P= 0.004). Multivariate analysis showed that RN (odds ratio 18.18), postoperative urinary pH < 6 (15.63), previous stone disease (13.7), age <60 years (7.33, all P < 0.001), body mass index ,30 kg/m2 (3.26, P= 0.033), male gender (2.67, P= 0.039), and hypobicarbonataemia (2.46, P= 0.034) were significantly associated with the development of postoperative calculi. CONCLUSIONS Patients undergoing RN have a significantly higher incidence of postoperative nephrolithiasis than a well-matched cohort undergoing NSS. In addition to RN, male sex, urinary pH < 6.0, hypobicarbonataemia, history of stone disease, obesity, and age <60 years were significantly associated with postoperative stone formation. [source] The effect of Phyllanthus niruri on urinary inhibitors of calcium oxalate crystallization and other factors associated with renal stone formationBJU INTERNATIONAL, Issue 9 2002A.M. Freitas Objective,To evaluate the effect of an aqueous extract of Phyllanthus niruri (Pn), a plant used in folk medicine to treat lithiasis, on the urinary excretion of endogenous inhibitors of lithogenesis, citrate, magnesium and glycosaminoglycans (GAGs). Materials and methods,The effect of chronic (42 days) administration of Pn (1.25 mg/mL/day, orally) was evaluated in a rat model of urolithiasis induced by the introduction of a calcium oxalate (CaOx) seed into the bladder of adult male Wistar rats. The animals were divided into four groups: a sham control (16 rats); a control+Pn (six); CaOx+water instead of Pn (14); and CaOx+Pn (22). Plasma and urine were collected after 42 days of treatment for biochemical analysis and the determination of urinary excretion of citrate, magnesium and GAGs. The animals were then killed and the calculi analysed. Results,The creatinine clearance or urinary and plasma concentrations of Na+, K+, Ca2+, oxalate, phosphate and uric acid were unaffected by Pn or the induction of lithiasis. Treatment with Pn strongly inhibited the growth of the matrix calculus and reduced the number of stone satellites compared with the group receiving water. The calculi were eliminated or dissolved in some treated animals (three of 22). The urinary excretion of citrate and magnesium was unaffected by Pn treatment. However, the mean (sd) urinary concentration of GAGs was significantly lower in rats treated with CaOx+Pn, at 5.64 (0.86) mg/g creatinine, than when treated with CaOx + water, at 11.78 (2.21) mg/g creatinine. In contrast, the content of GAGs in the calculi was higher in the CaOx + Pn rats, at 48.0 (10.4) g/g calculus, than in the CaOx + water group, at 16.6 (9.6) g/g calculus. Conclusion,These results show that Pn has an inhibitory effect on crystal growth, which is independent of changes in the urinary excretion of citrate and Mg, but might be related to the higher incorporation of GAGs into the calculi. [source] | |||||||||||||