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Calcium Oxalate (calcium + oxalate)
Terms modified by Calcium Oxalate Selected AbstractsCalcium oxalate and sulphate-containing structures on the thallial surface of the lichen Ramalina lacera: response to polluted air and simulated acid rainPLANT CELL & ENVIRONMENT, Issue 12 2002J. GARTY Abstract The formation of calcium-containing structures on the thallial surface of the lichen Ramalina lacera (With.) J.R. Laund. in response to air pollution and to simulated acid rain, was studied in in situ and transplanted thalli. In situ thalli were collected from an unpolluted site and transplanted to heavily polluted and less polluted sites for a 10 month period. Additional thalli were treated either with double distilled water or with simulated acid rain. Scanning electron microscopy and infrared spectrometry revealed that thallial surfaces of in situ R. lacera samples collected in unpolluted sites were covered with two kinds of calcium oxalate crystals: whewellite and weddellite. These aggregates of calcium oxalate crystals appear to disintegrate and provide a crystal layer on the thallial surface. Infrared spectroscopy of powder scraped from thallial surfaces of transplants, retrieved from non-polluted sites, showed the presence of whewellite and weddellite, whereas powders obtained from thalli retrieved from polluted sites contained whewellite, weddellite and gypsum. It is suggested that a certain fraction of the gypsum detected in crater-like structures in transplants from polluted sites and in thalli treated with simulated acid rain is endogenous and should be considered a biomineral. [source] Acute Oxalate Nephropathy Causing Late Renal Transplant Dysfunction Due to Enteric HyperoxaluriaAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2008A. C. Rankin Calcium oxalate (CaOx) deposition in the renal allograft is an under recognized and important cause of acute tubular injury and early allograft dysfunction. We present a case of late transplant dysfunction due to acute oxalate nephropathy. The patient presented with diarrhea and deteriorating graft function, and a diagnosis of enteric hyperoxaluria secondary to pancreatic insufficiency was made. This had occurred, as the patient had been noncompliant with his pancreatic enzyme replacement therapy. Treatment to reduce his circulating oxalate load was initiated, including twice-daily hemodialysis, low fat and oxalate diet and appropriate administration of pancreatic enzyme supplements. Graft function subsequently recovered. The possibility of fat malabsorption leading to enteric hyperoxaluria should be considered in renal graft recipients presenting with loose stools and graft dysfunction. [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] Numerical taxonomic evaluation of calcium oxalate and calcium carbonate crystals in the leaves of certain Ficus species (Moraceae)FEDDES REPERTORIUM, Issue 5-6 2004S. M. Sharawy Dr. The type and the distribution of calcium oxalate and calcium carbonate crystals were investigated in the leaves of 33 taxa of Ficus belonging to the three subgenera Urostigma, Ficus and Sycomorus for a speculation to the inter-subgeneric affinity. Numerical analysis of 55 characters grouped the taxa under 13 groups. The sizes of the latter with respect to the number of taxa they contain were calculated. Some resultant groups comprised taxa from different subgenera. So far as the present data are concerned and in agreement with previous workers, the var. decora of Ficus elastica and var. comosa of Ficus benjamina are better raised to the specific levels F. decoraHort and F. comosaRoxb. respectively. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Numerisch-taxonomische Auswertung von Calciumoxalat- und Calciumcarbonat-Kristallen in einigen Arten der Gattung Ficus (Moraceae) An den Blättern von 33 Taxa der Gattung Ficus aus den drei Subgenera Urostigma, Ficus und Sycomorus wurden die Art und die Verteilung von Calciumoxalat- und Calciumcarbonat-Kristallen untersucht, um ihre inter-subgenerische Verwandtschaft zu ermitteln. Num-merische Analysen von 55 Eigenschaften gestatten eine Unterteilung in 13 Gruppen. Der Umfang letzterer in Bezug auf die Anzahl der sie umfassenden Taxa wurde betrachtet. Einige dieser Gruppen umfassen Taxa aus unterschiedlichen Subgenera. Auf Grund der hier gewonnenen Daten und in Übereinstimmung mit früheren Bearbeitern werden Ficus elastica var. decora und F. benjamina var. comosa in den Artrang F. decoraHort bzw. F. comosaRoxb. erhoben. [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] Renal silica calculi in an infantINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2004TOSHIYUKI NISHIZONO Abstract, We report on a rare case of urinary silica calculi in a 10-month-old boy. The boy showed acute pyelonephritis with left hydronephrosis. Ultrasonography and computed tomography revealed a calculus at the left ureteropelvic junction and three additional calculi in the left renal pelvis. Because his acute pyelonephritis was refractory to conventional chemotherapy, the patient underwent successful left percutaneous nephrostomy followed by percutaneous nephrolithotripsy for the renal calculi. All stones disappeared and his postoperative course was uneventful. On infrared spectrophotometry, the wavelength pattern of the stones exhibited two peaks at 1100 and 1650 cm,1, consistent with the determination that the calculi consisted of a mixture of silicate (78%) and calcium oxalate (22%). We consider that the etiology of the calculi in this child can be ascribed to the silicate-rich water used to dilute milk. In Japan, 46 adult patients with urinary silicate calculi have been reported in the literature; however, there is no report of the disease in an infant in Japan. [source] Analysis of 4495 canine and feline uroliths in the Benelux.JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5-6 2007A retrospective study: 199 Summary From 1994 to 2004, Hill's Pet Nutrition received 4495 canine (65%) and feline (35%) uroliths from Benelux veterinary practitioners. They were sent to the Minnesota Urolith Center, USA for analysis. In 1994, 110 uroliths were analysed , 85% from dogs , and in 2003, 1067 uroliths were analysed , 59% from dogs. During this period, substantial changes were observed in composition. In 1994, 77% of the cats had uroliths composed of struvite, and 12% had uroliths composed of calcium oxalate. In 2003, feline uroliths were composed of 32% struvite, and 61% calcium oxalate. The same evolution was observed in the dogs. In 1994, 51% of canine uroliths were composed of struvite, and 33% of calcium oxalate. In 2003, 40% had struvite uroliths, and 46% had calcium oxalate uroliths. A significant effect of the size, the breed, and the gender were noticed in the dogs. The mean age of uroliths appearance was 7.3 years in the dogs and 7.2 years in the cats. The findings are similar to those previously published in the USA. [source] Investigation of impinging-jet crystallization with a calcium oxalate model systemAICHE JOURNAL, Issue 9 2003Jean M. Hacherl An impinging-jet crystallizer was investigated in this work to assess its operational sensitivity and reproducibility for the production of small, monodisperse crystals using calcium oxalate, a model system capable of forming multiple hydrates. The impinging-jet mixer provides rapid mixing of the reactant solutions through the impingement of two narrow reactant streams at high velocity. Impinging jet linear velocity and postjetting conditions were studied, with the jet operated in nonsubmerged mode. Hydrate form and crystal-size distribution (CSD) were determined using optical microscopy and image analysis techniques. The impinging jet consistently produced small, monodisperse crystals. However, at a high level of supersaturation, slight variations in the CSD were observed for apparently identical conditions, suggesting a degree of sensitivity in the system that could lead to difficulty in its application. An apparent trend between impinging-jet linear velocity and crystal size and number was observed, with more small crystals produced at higher linear velocity. [source] Epidemiology of canine urolithiasis in the Czech Republic from 1997 to 2002JOURNAL OF SMALL ANIMAL PRACTICE, Issue 4 2005M. Sosnar Objectives: To compare data on the epidemiology of canine urolithiasis in the Czech Republic with that from other countries. Methods: The records from the Centre for Mineralogical Analysis from 1997 to 2002 were reviewed. The data were obtained from mineralogical analysis of 1366 canine uroliths obtained from patients in the Czech Republic. These included 396 females and 629 males. Results: Sixty-eight breeds plus crossbreeds were identified. Eight breeds plus the crossbreeds accounted for 71.3 per cent of all cases. Males were affected more frequently than females (61.4 per cent versus 38.6 per cent). Struvites significantly predominated in females, while in males calcium oxalates, brushites and cystines were the most common stones. Most of the uroliths (48.9 per cent) were 5 mm or less in dimension. By 2001, struvite was the most frequent (38.5 to 44.1 per cent) urolith, followed by calcium oxalate (26.5 to 32.0 per cent). In 2002, calcium oxalate became the most frequent calculus, followed by struvite, mixed calculi and others. Clinical Significance: Comparison of these results with studies by other authors showed that for most of the monitored parameters there was agreement with respect to the proportions of different breeds within the populations of dogs in different geographical areas. [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] Idiopathic Hypercalcemia in CatsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2000A.M. Midkiff Unexplained hypercalcemia has been increasingly recognized in cats since 1990. In some instances, hypercalcemia has been associated with calcium oxalate urolithiasis, and some affected cats have been fed acidifying diets. We studied the laboratory findings, clinical course, and treatment of 20 cats with idiopathic hypercalcemia. Eight (40%) of the cats were longhaired and all 14 cats for which adequate dietary history was available had been fed acidifying diets. Clinical signs included vomiting (6 cats), weight loss (4 cats), dysuria (4 cats), anorexia (3 cats), and inappropriate urinations (3 cats). Hypercalcemia was mild to moderate in severity, and serum parathyroid hormone concentrations were normal or low. Serum concentrations of phosphorus, parathyroid hormone-related peptide, 25-hydroxycholecalciferol, and calcitriol were within the reference range in most cats. Diseases commonly associated with hypercalcemia (eg, neoplasia, primary hyperparathyroidism) were not identified despite thorough medical evaluations and long-term clinical follow-up. Azotemia either did not develop (10 cats) or developed after the onset of hypercalcemia (3 cats), suggesting that renal failure was not the cause of hypercalcemia in affected cats. Seven of 20 cats (35%) had urolithiasis, and in 2 cats uroliths were composed of calcium oxalate. Subtotal parathyroidectomy in 2 cats and dietary modification in 11 cats did not result in resolution of hypercalcemia. Treatment with prednisone resulted in complete resolution of hypercalcemia in 4 cats. [source] Changes in renal hemodynamics and urodynamics in rats with chronic hyperoxaluria and after acute oxalate infusion: Role of free radicalsNEUROUROLOGY AND URODYNAMICS, Issue 2 2003Ho-Shiang Huang Abstract Aims The aim of this study was to evaluate possible changes in renal hemodynamic and urodynamic parameters in rats with chronic hyperoxaluria and after acute oxalate challenge. We also evaluated the possible association between free radical (FR) production, hyperoxaluria, and calcium oxalate (CaOx) calculi formation. Methods Chronic hyperoxaluria was induced by adding 0.75% ethylene glycol (EG) to the drinking water of male Wistar rats. After 7, 21, and 42 days of treatment, urinary biochemistry, oxalate levels, and lipid peroxides were measured. Kidney calculi were examined by polarizing microscopy. In the second part of the experiments, 1, 10, 20, and 30 mg kg,1 hr,1 oxalate was infused, by means of an intrarenal arterial catheter (IRA), into normal rats sequentially. Superoxide dismutase (SOD) infusion by means of IRA, in addition to oxalate, was also performed to check its influence on the altered renal function after oxalate infusion. In both the acute and chronic groups, renal blood flow (RBF), cortical microvascular blood flow (CMVBF), glomerular filtration rate (GFR), urine flow (UV), and urinary sodium excretion (UNaV) were measured, and chemiluminescence (CL) was examined in the renal venous blood. Results Levels of urinary lipid peroxides and enzymuria had increased since day 7, and increased the size of numbers of CaOx crystals in the kidney were noted beginning on day 21, but elevated CL was detectable only on day 7 after 0.75% EG treatment. Decreased UV and UNaV were noted in the 42-day EG group, although the 24-hr creatinine clearance values were normal in all experimental groups. On the other hand, RBF, GFR, and CMVBF were attenuated with elevated FR when the oxalate concentration was higher than 10 mg kg,1 hr,1 in the acute oxalate infusion group. With SOD pretreatment, the decreased RBF, GFR, and CMVBF could be reversed at 10 mg kg,1 hr,1 of oxalate, and be partially reversed at 20. FR also could be reduced significantly at 10 and 20 mg kg,1 hr,1 of oxalate. Conclusions Decreased urine flow and sodium excretion were the main renal functions affected by chronic hyperoxaluria. However, that only the 42-day EG group had a decreased tubular function cannot be fully explained by the persistent tubular enzymuria and increased lipid peroxides that began on day 7 after EG treatment. With acute oxalate infusion, the major insult to renal function was renal hemodynamics. Pretreated SOD could reverse the attenuated hemodynamics and reduce the elevated FR partly, which suggested that FR is responsible for oxalate toxicity. Neurourol. Urodynam. 22:176,182, 2003. © 2003 Wiley-Liss, Inc. [source] Identification of human calculi with time-of-flight secondary ion mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 2 2010C. Amjad A. Ghumman Time-of-flight secondary ion mass spectrometry was used to study four human calculi and to compare the results with those from twelve commercially available urinary calculi minerals including three organic compounds (L-cystine, uric acid and sodium urate). Phase identification of calcium phosphate compounds was carried out by considering the relative ion abundances of [Ca2O]+ and [CaPO2]+. Deprotonated [M,H], and protonated [M+H]+ uric acid were detected and used for component recognition in pure uric acid and in the mixed samples of struvite, calcium oxalate and uric acid. Iodine related to the medical history of a patient was also detected. Copyright © 2009 John Wiley & Sons, Ltd. [source] Mechanism of Formation of Human Calcium Oxalate Renal Stones on Randall's PlaqueTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2007Andrew P. Evan Abstract Although calcium oxalate (CaOx) renal stones are known to grow attached to renal papillae, and specifically to regions of papillae that contain Randall's plaque (interstitial apatite deposits), the mechanisms of stone overgrowth on plaque are not known. To investigate the problem, we have obtained biopsy specimens from two stone patients that included an attached stone along with its tissue base and have studied the ultrastructural features of the attachment point using light and transmission electron microscopy, Fourier transform infrared spectroscopy (,-FTIR), and immunohistochemical analysis. The epithelium is disrupted at the attachment site. The denuded plaque that borders on the urinary space attracts an envelope of ribbon-like laminates of crystal and organic matrix arising from urine ions and molecules. Into the matrix of this ribbon grow amorphous apatite crystals that merge with and give way to the usual small apatite crystals imbedded in stone matrix; eventually CaOx crystals admix with apatite and become the predominant solid phase. Over time, urine calcium and oxalate ions gradually overgrow on the large crystals forming the attached stone. Anat Rec, 290:1315-1323, 2007. © 2007 Wiley-Liss, Inc. [source] Early Presence of Calcium Oxalate Deposition in Kidney Graft Biopsies is Associated with Poor Long-Term Graft SurvivalAMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2005Hélady Sanders Pinheiro Accumulated oxalate will be excreted after renal transplantation, creating an increased risk of tubular precipitation, especially in the presence of allograft dysfunction. We evaluated calcium oxalate (CaOx) deposition in renal allograft biopsies with early dysfunction, its association with acute tubular necrosis (ATN) and graft survival. We studied 97 renal transplant patients, submitted to a graft biopsy within 3 months post-transplant, and reanalyzed them after 10 years. We analyzed renal tissue under polarized light and quantified CaOx deposits. CaOx deposits were detected in 52.6% of the patients; 26.8% were of mild and 25.8% of moderate intensity. The deposits were more frequent in biopsies performed within 3 weeks post-transplant (82.4 vs. 63.0%, p < 0.05) and in allografts with more severe renal dysfunction (creatinine 5.6 mg/dL vs. 3.4 mg/dL, p < 0.001). ATN incidence was also higher in patients with CaOx deposits (47% vs. 24%, p < 0.001). Twelve-year graft survival was strikingly worse in patients with CaOx deposits compared to those free of deposits (49.7 vs. 74.1%, p = 0.013). Our study shows a high incidence of CaOx deposits in kidney allografts with early dysfunction, implying an additional risk for acute tubular injury, with a negative impact on graft survival. [source] Oxalate ions and calcium oxalate crystal-induced up-regulation of osteopontin and monocyte chemoattractant protein-1 in renal fibroblastsBJU INTERNATIONAL, Issue 3 2006TOHRU UMEKAWA OBJECTIVE To examine the responses of renal fibroblasts to high oxalate (Ox) and calcium Ox (CaOx) crystals, as the latter are found in the renal interstitium of patients with primary or enteric hyperoxaluria, and in animals with experimental CaOx nephrolithiasis, and are associated with tubulointerstitial inflammation (TI). TI might begin with the production of chemoattractants by the renal epithelial cells exposed to high Ox and/or CaOx crystals; as Ox levels are also high in the renal interstitium and crystal deposition in nephrolithiasis might start in the interstitium, we hypothesized that renal fibroblasts might also be involved in the development of TI. MATERIALS AND METHODS We exposed renal fibroblast cells of line NRK 49F in vitro to Ox ions (500 µmol/L) or CaOx monohydrate crystals (67 µg/cm2). We assessed the production of osteopontin and monocyte chemoattractant protein-1 (MCP-1), and expression of their mRNA, in the cells. We also determined the cellular malondialdehyde content as a marker of reactive oxygen species (ROS)-induced lipid peroxidation, and Trypan blue staining and the release of lactate dehydrogenase as markers of injury. RESULTS Similar to renal epithelial cells, renal fibroblasts were stimulated by exposure to Ox and CaOx crystals. They showed signs of injury and ROS-induced lipid peroxidation. The mRNA expression and production of osteopontin and MCP-1 increased significantly. CONCLUSIONS These results indicate that fibroblasts respond to high Ox and CaOx crystals by up-regulating specific pathways producing pro-inflammatory conditions. Migration of monocytes/macrophages to sites of interstitial crystal deposits can lead to localized interstitial inflammation and fibrosis. [source] Enlargement of calcium oxalate stones to clinically significant size in an in-vitro stone generatorBJU INTERNATIONAL, Issue 9 2002K. Ananth Objective ,To develop and validate an in vitro method suitable for the quantitative investigation of the growth of calcium oxalate stones through to a clinically significant size. Materials and methods ,Small fragments of calcium oxalate calculi were suspended in a mixed suspension/mixed product removal crystalliser supplied with artificial urine supersaturated with calcium oxalate. The fragments were weighed at regular intervals until they reached ,,500 mg. The results were plotted as weight against time and fitted to equations corresponding to constant increase in diameter, surface area-controlled and constant-deposition growth patterns. The choice of the most appropriate model was based on the squared regression coefficient (r2). Results ,Eight fragments (2,6 mm in diameter) were grown to ,,10 mm in diameter over periods from 137 to 369 h. Seven of the growth curves were best-fitted (r2 , 0.988) by the equation w = kt(3/2) + c, where w is the weight, k is a growth constant, t is the time and c is a constant approximating to the initial weight. This corresponds to a surface area-dependent mechanism. Conclusions ,The growth of these small fragments to a clinically significant size accelerated throughout the experimental period in a way which was consistent with a surface area-dependent mechanism. We have developed a resilient model suitable for studying the kinetics of calcium oxalate stone growth in vitro. [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] Epidemiology of canine urolithiasis in the Czech Republic from 1997 to 2002JOURNAL OF SMALL ANIMAL PRACTICE, Issue 4 2005M. Sosnar Objectives: To compare data on the epidemiology of canine urolithiasis in the Czech Republic with that from other countries. Methods: The records from the Centre for Mineralogical Analysis from 1997 to 2002 were reviewed. The data were obtained from mineralogical analysis of 1366 canine uroliths obtained from patients in the Czech Republic. These included 396 females and 629 males. Results: Sixty-eight breeds plus crossbreeds were identified. Eight breeds plus the crossbreeds accounted for 71.3 per cent of all cases. Males were affected more frequently than females (61.4 per cent versus 38.6 per cent). Struvites significantly predominated in females, while in males calcium oxalates, brushites and cystines were the most common stones. Most of the uroliths (48.9 per cent) were 5 mm or less in dimension. By 2001, struvite was the most frequent (38.5 to 44.1 per cent) urolith, followed by calcium oxalate (26.5 to 32.0 per cent). In 2002, calcium oxalate became the most frequent calculus, followed by struvite, mixed calculi and others. Clinical Significance: Comparison of these results with studies by other authors showed that for most of the monitored parameters there was agreement with respect to the proportions of different breeds within the populations of dogs in different geographical areas. [source] | ||||||||||||||||