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Stone Formers (stone + former)
Selected AbstractsUrinary macromolecules and renal tubular cell protection from oxalate injury: Comparison of normal subjects and recurrent stone formersINTERNATIONAL JOURNAL OF UROLOGY, Issue 3 2006MASAO TSUJIHATA Aim:, To determine whether urinary macromolecules (UMM), which are the high molecular weight substances in urine, can provide protection against the oxalate-associated injury to the renal tubular cells. Methods:, UMM were extracted from 24-h urine of 12 healthy adult male volunteers and 13 recurrent-stone-former male patients. Urine parameters in relation to urolithiasis were measured, including the level of glycosaminoglycans (GAG) in the UMM. Madin-Darby canine kidney (MDCK) cells were used to evaluate the protective activity of UMM from oxalate-induced cytotoxicity by LDH release measurement and methyl-thiazolyl tertrazolium (MTT) assay. Results:, Considering urinary parameters, citrate was significantly higher in urine from normal subjects than stone-former subjects; the other parameters show no differences between the groups. Total UMM and the level of GAG in the UMM were also significantly higher in the normal subject group. Compared with normal subject and stone-former subject UMM, after cells were treated with the UMM and then exposed to oxalate solution, LDH release was significantly higher in stone-former group. In the MTT assay, we found that more viable cells were observed after treatment with UMM compared to control in both groups. Moreover, UMM from the normal subjects showed higher protective activity against oxalate-related cytotoxicity than UMM from the stone-former subjects. Conclusion:, UMM protected renal epithelial cells from oxalate-related injury. This protective activity was found to be higher in normal subject UMM than stone-former UMM. Among other factors, a higher concentration of GAG and citrate in normal subject UMM might affect some parts in this finding. [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] 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] Attributing Hardy-Weinberg Disequilibrium to Population Stratification and Genetic Association in Case-Control StudiesANNALS OF HUMAN GENETICS, Issue 1 2010Vaneeta K. Grover Summary Loci exhibiting Hardy-Weinberg disequilibrium (HWD) are often excluded from association studies, because HWD may indicate genotyping error, population stratification or selection bias. For case-control studies, HWD can result from a genetic effect at the locus. We extend the modelling to accommodate both stratification and genetic effects. Theoretical genotype frequencies and HWD coefficients are derived under a general genetic model for a population with two strata. Maximum likelihood is used to estimate model parameters and a test for lack of fit identifies the models most consistent with the data. Simulations were used to assess the method. The technique was applied to a group of ethnically and clinically heterogeneous kidney stone formers and controls, both exhibiting HWD for the R990G SNP of the CASR gene. Results indicate the best fitting model incorporates both stratification and genetic association. The ability of our method to apportion HWD to stratification and genetic effects may well be a significant advance in dealing with heterogeneity in case-control genetic association studies. [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] Outcomes using a fourth-generation lithotripter: a new benchmark for comparison?BJU INTERNATIONAL, Issue 6 2007Michael S. Nomikos OBJECTIVE To evaluate the efficacy of a fourth-generation lithotripter, the Sonolith Vision (Technomed Medical Systems, Vaulx-en-Velin, France) for treating single previously untreated renal calculi, and to compare the results with the reference standard HM-3 (Dornier MedTech Europe GmbH, Wessling, Germany) in the same population originally studied by the USA Cooperative Study Group in 1986. PATIENTS AND METHODS The Sonolith Vision uses an innovative electroconductive shock-wave generator with an elliptical reflector specially designed to give the maximum concentration of energy on the stone. We reviewed the treatment sessions from our prospectively maintained database of the first 1000 consecutive patients with urinary stone disease who were treated with the Sonolith Vision between September 2004 and March 2006. Patients with previously untreated solitary renal calculi in anatomically normal kidneys were included. The outcome was assessed by plain films for radio-opaque stones, and renal ultrasonography for radiolucent stones, at 1 and 3 months after lithotripsy; the results were analysed according to stone size and location. RESULTS Data from 309 patients who had a complete follow-up and with 373 renal calculi that matched the above criteria were analysed. The initial fragmentation rate was 94%. The stone-free rate for stones of <10 mm was 77%, for 11,20 mm was 69% and for >20 mm was 50%. The overall stone-free rate 3 months after lithotripsy was 75%. Within a month of lithotripsy, 221 patients (59%) became stone-free. Additional procedures to render patients stone-free after lithotripsy were needed in only 22 cases (7%). The overall efficiency quotient was 62%. The stone-free rates for lower, upper, middle calyceal and renal pelvic calculi were 74%, 70%, 78.5% and 75%, respectively. There were no serious complications. CONCLUSIONS When similar populations of stone formers were assessed the Sonolith Vision achieved a high success rate, comparable with that using the HM-3 machine but with lower analgesia requirements and very low re-treatment rates. This method of comparison belies the commonly held view that newer lithotripters are less effective than the original spark-gap machines. [source] | |||||||||||||