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Sample records for oxalate monohydrate stone

  1. Prediction of calcium oxalate monohydrate stone composition during ureteroscopy

    NASA Astrophysics Data System (ADS)

    Hamidizedah, Reza; Melnyk, Megan; Teichman, Joel M. H.

    2012-02-01

    Introduction: Prior research shows that Ho:YAG lithotripsy produces tiny dust fragments at low pulse energy (0.2J). However, calcium oxalate monohydrate (COM) stones may not fragment at this low pulse energy setting. Stone composition is rarely known until after surgery and historically, attempts to predict stone composition on the basis of endoscopic stone appearance were unsuccessful. Current endoscopic technology permits visual details that previously were not evident. As COM appears black under ambient light, we attempt to predict COM stone composition at the time of ureteroscopy based on its endoscopic appearance. Methods: Consecutive subjects undergoing ureteroscopy for stone disease were studied. Any portion of the stone that appeared black under endoscopic vision was considered clinical evidence of COM. Predicted stone composition was correlated with post-operative calculus analysis. Results: 46 consecutive ureteroscopic stone cases were analyzed prospectively. 25 of 28 subjects (89%) with black stones had stones later proven to be COM by composition analysis, versus one of 18 patients (6%) with non-black stones that were COM (p<0.0001). A black endoscopic stone appearance had a positive predictive value for COM of 89% and a non-black endoscopic stone appearance had a negative predictive value for COM of 94% (sensitivity 96%, specificity 83%). Conclusions: COM may reasonably be predicted intra-operatively by its black endoscopic appearance. The clinical utility would be to use higher laser pulse energy settings than for non-COM compositions. This data raises the possibility that more sophisticated optical characterization of endoscopic stone appearance may prove to be a useful tool to predict stone composition.

  2. Face-specific molecular adhesion and binding to calcium oxalate monohydrate: Implication for kidney stone formation

    NASA Astrophysics Data System (ADS)

    Sheng, Xiaoxia

    This thesis focuses on the face-specific molecular adhesion to calcium oxalate monohydrate (COM) crystals, the principal crystalline in kidney stones. The primary technique used is atomic force microscopy (AFM), which allows visualizing the structure and growth of crystals, measuring the adhesion force between functional groups and crystal faces, and examining adhesion and binding of the molecules to crystals. The microscopic events associated with crystal growth on the {100}, {12-1}, and {010} faces have been investigated. Each face exhibits hillocks with step sites that can be assigned to specific crystal planes, enabling direct determination of growth rates along specific crystallographic directions. The growth rates are found to depend on the degree of supersaturation. The addition of macromolecules with anionic side chains results in inhibition of hillock growth. The magnitude of this effect depends on the macromolecule structure & concentration, and the identity of the step site. The different profiles observed for three synthetic macromolecules, which have similar backbones but different side chains, argues that local binding of anionic side chains to crystal surface sites governs growth inhibition rather than any secondary polymer structure. The dependence of adhesion force on the functional group-COM crystal face combinations has been identified. Tip-immobilized carboxylate and amidinium groups display the largest adhesion forces among all the functional groups examined, and the adhesive strength decreases as (100) > (12-1) > (010). The more adherent surface of COM, compared with its dihydrate form COD, corroborates the critical role of COM in stone formation. The influence of small molecules, synthetic polymers and native proteins on adhesion was examined. The introduction of these molecular additives, except osteopontin, result in a reduction in the adhesion force measured for all three faces. The extent of suppression, however, varies for molecule-crystal face combination. Curiously, osteopontin exhibits a unique behavior as it increased the adhesion force between the carboxylate tip and the (100) crystal face. Collectively, the force measurements demonstrate that adhesion of functional groups and binding of soluble additives, including urinary macromolecules, to COM crystal surfaces are highly specific in nature.

  3. Analysis of Altered MicroRNA Expression Profiles in Proximal Renal Tubular Cells in Response to Calcium Oxalate Monohydrate Crystal Adhesion: Implications for Kidney Stone Disease

    PubMed Central

    Wang, Bohan; Wu, Bolin; Liu, Jun; Yao, Weimin; Xia, Ding; Li, Lu; Chen, Zhiqiang; Ye, Zhangqun; Yu, Xiao

    2014-01-01

    Background Calcium oxalate monohydrate (COM) is the major crystalline component in kidney stones and its adhesion to renal tubular cells leads to tubular injury. However, COM-induced toxic effects in renal tubular cells remain ambiguous. MicroRNAs (miRNAs) play an important role in gene regulation at the posttranscriptional levels. Objective The present study aimed to assess the potential changes in microRNAs of proximal renal tubular cells in response to the adhesion of calcium oxalate monohydrate (COM) crystals. Methodology Lactate dehydrogenase (LDH) activity and DAPI staining were used to measure the toxic effects of HK-2 cells exposed to COM crystals. MicroRNA microarray and mRNA microarray were applied to evaluate the expression of HK-2 cells exposed to COM crystals. Quantitative real-time PCR (qRT-PCR) technology was used to validate the microarray results. Target prediction, Gene Ontology (GO) analysis and pathway analysis were applied to predict the potential roles of microRNAs in biological processes. Principal Findings Our study showed that COM crystals significantly altered the global expression profile of miRNAs in vitro. After 24 h treatment with a dose (1 mmol/L), 25 miRNAs were differentially expressed with a more than 1.5-fold change, of these miRNAs, 16 were up-regulated and 9 were down-regulated. A majority of these differentially expressed miRNAs were associated with cell death, mitochondrion and metabolic process. Target prediction and GO analysis suggested that these differentially expressed miRNAs potentially targeted many genes which were related to apoptosis, regulation of metabolic process, intracellular signaling cascade, insulin signaling pathway and type 2 diabetes. Conclusion Our study provides new insights into the role of miRNAs in the pathogenesis associated with nephrolithiasis. PMID:24983625

  4. Natural promoters of calcium oxalate monohydrate crystallization.

    PubMed

    Farmanesh, Sahar; Chung, Jihae; Sosa, Ricardo D; Kwak, Jun Ha; Karande, Pankaj; Rimer, Jeffrey D

    2014-09-10

    Crystallization is often facilitated by modifiers that interact with specific crystal surfaces and mediate the anisotropic rate of growth. Natural and synthetic modifiers tend to function as growth inhibitors that hinder solute attachment and impede the advancement of layers on crystal surfaces. There are fewer examples of modifiers that operate as growth promoters, whereby modifier-crystal interactions accelerate the kinetic rate of crystallization. Here, we examine two proteins, lysozyme and lactoferrin, which are observed in the organic matrix of three types of pathological stones: renal, prostatic, and pancreatic stones. This work focuses on the role of these proteins in the crystallization of calcium oxalate monohydrate (COM), the most prominent constituent of human kidney stones. Using a combination of experimental techniques, we show that these proteins, which are rich in l-arginine and l-lysine amino acids, promote COM growth. The synthesis and testing of peptides derived from contiguous segments of lysozyme's primary amino acid sequence revealed subdomains within the protein that operate either as an inhibitor or promoter of COM growth, with the latter exhibiting efficacies that nearly match that of the protein. We observed that cationic proteins promote COM growth over a wide range of modifier concentration, which differs from calcification promoters in the literature that exhibit dual roles as promoters and inhibitors at low and high concentration, respectively. This seems to suggest a unique mechanism of action for lysozyme and lactoferrin. Possible explanations for their effects on COM growth and crystal habit are proposed on the basis of classical colloidal theories and the physicochemical properties of peptide subdomains, including the number and spatial location of charged or hydrogen-bonding moieties. PMID:25119124

  5. Role of magnesium in the growth of calcium oxalate monohydrate and calcium oxalate dihydrate crystals.

    PubMed

    Oka, T; Yoshioka, T; Koide, T; Takaha, M; Sonoda, T

    1987-01-01

    Since about 85% of synthesized calcium oxalate dihydrate (COD) crystals proved not to have changed into calcium oxalate monohydrate (COM) crystals at 30 min of incubation time at 37 degrees C when our evaluation method of the COD-to-COM ratio was being used, we made a comparative study of the inhibitory effects of magnesium, one of the well-known inhibitors of calcium oxalate stone formation, on the growth of seeded COM and COD crystals. The results demonstrated that magnesium in identical concentrations might have stronger inhibitory effects on the growth of COM crystals than on that of COD crystals and suggested that these different effects of magnesium on the growth of COM and COD crystals might arise not only from the difference between the specific surface areas of COM and COD crystals, but also from that between the direct inhibitory effects of magnesium on these two types of calcium oxalate crystal growth. PMID:3617248

  6. Agglomeration of calcium oxalate monohydrate in synthetic urine.

    PubMed

    Grases, F; Masrov, L; Shnel, O; Costa-Bauz, A

    1992-09-01

    The development of agglomerated particles of calcium oxalate monohydrate (COM) on the semi-batch precipitation from a synthetic urine carried out at physiological conditions (37 degrees C, pH = 5.5) was studied by optical and electron scanning microscopy. COM agglomerates develop by primary and secondary agglomeration proceeding simultaneously; the latter mechanism is, however, less important than the former. Citrate ions modify slightly the COM crystal shape and inhibit primary agglomeration. Mucin particles serve as a substrate for preferential formation (nucleation) of new COM crystals. The structure of formed agglomerates closely resembles that of a certain type of COM renal calculi. A combination of primary agglomeration of crystals forming stones and nucleation of new crystals on a mucoprotein layer partially covering their surface constitutes the possible mechanism of such stone development. Experimental data support this mechanism. PMID:1422681

  7. Protein adsorption at calcium oxalate monohydrate crystal surfaces.

    NASA Astrophysics Data System (ADS)

    Wesson, J.; Sheng, X.; Rimer, J.; Jung, T.; Ward, M.

    2008-03-01

    Calcium oxalate monohydrate (COM) crystals are the dominant inorganic phase in most kidney stones, and kidney stones form as aggregates of COM crystals and organic material, principally proteins, but little is known about the molecular level events at COM surfaces that regulate COM aggregation. We have examined the influence of polyelectrolytes on the force of adhesion between chemically modified atomic force microscopy (AFM) tips and selected COM crystal faces in saturated solution. In general, we found that polyanions bind to COM surfaces and block adhesion of a carboxylate functionalized AFM tip, while polycations had no measureable effect on adhesion force under the same conditions. We did observe a unique absence of interaction between poly(glutamic acid) and the COM (100) face compared to other synthetic polyanions, and some native urinary protein structures also exhibited unique face selective interactions, suggesting that simple electrostatic models will not completely explain the data.

  8. Lowering urinary oxalate excretion to decrease calcium oxalate stone disease.

    PubMed

    Holmes, Ross P; Knight, John; Assimos, Dean G

    2016-02-01

    Dietary modifications should be considered as a first line approach in the treatment of idiopathic calcium oxalate nephrolithiasis. The amounts of oxalate and calcium consumed in the diet are significant factors in the development of the disease due to their impact on urinary oxalate excretion. There are a number of strategies that can be employed to reduce oxalate excretion. The consumption of oxalate-rich foods should be avoided and calcium intake adjusted to 1000-1200mg/day. To encourage compliance it should be emphasized to patients that they be vigilant with this diet as a deviation in any meal or snack could potentially result in significant stone growth. The evidence underlying these two modifications is outlined and other strategies to reduce urinary oxalate excretion are reviewed. PMID:26614109

  9. Kinetic factors influencing the dissolution behavior of calcium oxalate renal stones: a constant composition study.

    PubMed

    White, D J; Coyle-Rees, M; Nancollas, G H

    1988-11-01

    A constant composition method has been used to examine the dissolution kinetics of calcium oxalate renal stones over a wide range of undersaturation in vitro. Demineralization experiments have been carried out with the concentrations of calcium and oxalate ions and ionic strength (hence the solution undersaturation) held constant by the potentiometrically controlled addition of medium electrolyte solution as diluent, triggered by a calcium ion electrode. Kinetic data for renal stones have been compared with results obtained for synthetic calcium oxalate. In addition, constant composition results have been directly compared with results obtained using conventional dissolution methods for both calculi and synthetic calcium oxalate. Overall, calcium oxalate renal stones exhibited markedly different kinetic dissolution behavior as compared with synthetic controls. The renal stone samples dissolved more slowly at all undersaturations, exhibited increased kinetic orders of reaction, and showed reduced sensitivity to solution hydrodynamics. Stones composed of mixed hydrates of calcium oxalate (mono- and di-) came to dihydrate equilibrium in conventional experiments and underwent net dissolution in solutions supersaturated to monohydrate under constant composition conditions. No conversion of di- to monohydrate was observed under these experimental conditions. These results indicate that stone dissolution is strongly influenced by adsorbed inhibitors, presumably including matrix components, which may complicate efforts to develop systemic and/or irrigation measures effective for in situ solubilization. PMID:3145798

  10. The nucleation and growth of calcium oxalate monohydrate on self- assembled monolayers (SAMs)

    SciTech Connect

    Campbell, A.A.; Tarasevich, B.J.; Graff, G.L.; Fryxell, G.E.; Rieke, P.C.

    1992-05-01

    A physical chemical approach was used to study calcium oxalate monohydrate (COM) nucleation and growth on various organic interfaces. Self-assembling monolayers (SAMs), containing derivatized organic functional groups, were designed to mimic various amino acid residues present in both urine and stone matrix macromolecules. Derivatized surfaces include SAMs with terminal methyl, bromo, imidazole, and thiazolidine-carboxylic acid functional groups. Pronounced differences in COM deposition were observed for the various interfaces with the imidazole and thiazolidine surfaces having the greatest effect and the methyl and bromo groups having little or no nucleating potential.

  11. Microelectrophoretic study of calcium oxalate monohydrate in macromolecular solutions

    NASA Technical Reports Server (NTRS)

    Curreri, P. A.; Onoda, G. Y., Jr.; Finlayson, B.

    1987-01-01

    Electrophoretic mobilities were measured for calcium oxalate monohydrate (COM) in solutions containing macromolecules. Two mucopolysaccharides (sodium heparin and chondroitin sulfate) and two proteins (positively charged lysozyme and negatively charged bovine serum albumin) were studied as adsorbates. The effects of pH, calcium oxalate surface charge (varied by calcium or oxalate ion activity), and citrate concentration were investigated. All four macromolecules showed evidence for adsorption. The macromolecule concentrations needed for reversing the surface charge indicated that the mucopolysaccharides have greater affinity for the COM surface than the proteins. Citrate ions at high concentrations appear to compete effectively with the negative protein for surface sites but show no evidence for competing with the positively charged protein.

  12. Inhibition of calcium oxalate monohydrate crystallization by the combination of citrate and osteopontin

    NASA Astrophysics Data System (ADS)

    Wang, Lijun; Zhang, Wei; Qiu, S. Roger; Zachowicz, William J.; Guan, Xiangying; Tang, Ruikang; Hoyer, John R.; De Yoreo, James J.; Nancollas, George H.

    2006-05-01

    The design of effective crystallization inhibitors of calcium oxalate monohydrate (COM), the primary constituent of kidney stones, is a significant goal. Inhibitory molecules identified in urine include a small organic anion, citrate, and osteopontin (OPN), an aspartic acid-rich protein. The results of molecular-scale analyses combining force microscopy with molecular modeling raised the possibility that inhibition of COM crystallization might be increased by the additive effects of citrate and OPN because they act on different crystal faces. Constant composition (CC) kinetics studies of COM crystal growth now confirm that additive effects are, indeed, achieved in vitro when both citrate and OPN are present. These results suggest that a strategy employing combinations of inhibitors may provide a useful therapeutic approach to urinary stone disease.

  13. The growth morphology of calcium oxalate trihydrate. A contribution to urinary stone research

    NASA Astrophysics Data System (ADS)

    Heijnen, Wim M. M.

    1982-04-01

    A PBC analysis of the calcium oxalate trihydrate (COT) structure results in PBCs in 15 different directions, which can be combined to 17 theoretical F forms. When the differences in bond strength are taken into account, the crystal form {010} appears to be dominant. This is in good agreement with the platy habit of most synthetic crystals. EHDP, an inhibitor for calcium oxalate monohydrate (COM) growth, stabilizes COT at the expense of COM, both at 12 and 37C; additionally, its presence produces a change in COT morphology: {001} becomes the most important form in contrast with the normally dominant {010}. The first occurrence of COT in a urinary stone is recorded.

  14. The electrokinetic behavior of calcium oxalate monohydrate in macromolecular solutions

    NASA Technical Reports Server (NTRS)

    Curreri, P. A.; Onoda, G. Y., Jr.; Finlayson, B.

    1988-01-01

    Electrophoretic mobilities were measured for calcium oxalate monohydrate (COM) in solutions containing macromolecules. Two mucopolysaccharides (sodium heparin and chrondroitin sulfate) and two proteins (positively charged lysozyme and negatively charged bovine serum albumin) were studied as adsorbates. The effects of pH, calcium oxalate surface charge (varied by calcium or oxalate ion activity), and citrate concentration were investigated. All four macromolecules showed evidence for chemical adsorption. The macromolecule concentrations needed for reversing the surface charge indicated that the mucopopolysacchrides have greater affinity for the COM surface than the proteins. The amount of proteins that can chemically adsorb appears to be limited to approximately one monomolecular layer. When the surface charge is high, an insufficient number of proteins can chemically adsorb to neutralize or reverse the surface charge. The remaining surface charge is balanced by proteins held near the surface by longer range electrostatic forces only. Citrate ions at high concentrations appear to compete effectively with the negative protein for surface sites but show no evidence for competing with the positively charged protein.

  15. Aggregation of Calcium Phosphate and Oxalate Phases in the Formation of Renal Stones

    PubMed Central

    2015-01-01

    The majority of human kidney stones are comprised of multiple calcium oxalate monohydrate (COM) crystals encasing a calcium phosphate nucleus. The physiochemical mechanism of nephrolithiasis has not been well determined on the molecular level; this is crucial to the control and prevention of renal stone formation. This work investigates the role of phosphate ions on the formation of calcium oxalate stones; recent work has identified amorphous calcium phosphate (ACP) as a rapidly forming initial precursor to the formation of calcium phosphate minerals in vivo. The effect of phosphate on the nucleation of COM has been investigated using the constant composition (CC) method in combination with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Our findings indicate COM nucleation is strongly promoted by the presence of phosphate; this occurs at relatively low phosphate concentrations, undersaturated with respect to brushite (dicalcium phosphate dehydrate, DCPD) formation. The results show that ACP plays a crucial role in the nucleation of calcium oxalate stones by promoting the aggregation of amorphous calcium oxalate (ACO) precursors at early induction times. The coaggregations of ACP and ACO precursors induce the multiple-point nucleation of COM. These novel findings expand our knowledge of urinary stone development, providing potential targets for treating the condition at the molecular level. PMID:25598742

  16. Reversible inhibition of calcium oxalate monohydrate growth by an osteopontin phosphopeptide.

    PubMed

    Nene, Shailesh S; Hunter, Graeme K; Goldberg, Harvey A; Hutter, Jeffrey L

    2013-05-28

    Calcium oxalate, primarily as calcium oxalate monohydrate (COM), is the primary constituent of most kidney stones. Certain proteins, such as osteopontin (OPN), inhibit stone formation. The complexity of stone formation and the effects of urinary proteins at various stages of the process make it hard to predict the exact physiological roles of these proteins in growth inhibition. The inhibition of crystallization due to adsorbed impurities is usually explained in terms of a model proposed in 1958 by Cabrera and Vermilyea. In this model, impurities adsorb to growth faces and pin growth steps, forcing them to curve, thus impeding their progress via the Gibbs-Thomson effect. To determine the role of OPN in the biomineralization of kidney stones, crystal growth on the {010} face of COM was examined in real time with atomic force microscopy in the presence of a synthetic peptide corresponding to amino acids 65-80 (hereafter referred to as pOPAR) of rat bone OPN. We observed clear changes in the morphology of the growth-step structure and a decrease in step velocity upon addition of pOPAR, which suggest adsorption of inhibitors on the {010} growth hillocks. Experiments in which pOPAR was replaced in the growth cell by a supersaturated solution showed that COM hillocks are able to fully recover to their preinhibited state. Our results suggest that recovery occurs through incorporation of the peptide into the growing crystal, rather than by, e.g., desorption from the growth face. This work provides new insights into the mechanism by which crystal growth is inhibited by adsorbants, with important implications for the design of therapeutic agents for kidney stone disease and other forms of pathological calcification. PMID:23611580

  17. Studies on calcium oxalate monohydrate crystallization: influence of inhibitors.

    PubMed

    Grases, F; Kroupa, M; Costa-Bauzá, A

    1994-01-01

    A simple model to study calcium oxalate monohydrate (COM) crystallization on different substrates is presented and the action of different potential inhibitors is evaluated and discussed. COM heterogeneous nucleation was assayed on solid surfaces as calcium phosphate, mixtures of mucin with calcium phosphate, and wax. In the presence of a non-protected non-renewed solid surface in contact with normal urine, COM crystal formation could be detected at short intervals (3 h). The most active heterogeneous nucleation capacity corresponded to calcium phosphate. In the presence of 10% mucin, owing to the renewal of the surface layer no COM crystal were detected on the pellet's surface. The study of citrate and pentosan polysulphate (a semisynthetic polysaccharide) on COM heterogeneous nucleation demonstrated some important inhibitory effects when concentration increased and time decreased. Maximum effects were selectively manifested on calcium phosphate surfaces. Only phytic acid at adequate concentration exhibited a total inhibitory capacity of COM formation, even during longer intervals (15 h). PMID:7521089

  18. Modulation of calcium oxalate monohydrate crystallization kinetics in vitro.

    PubMed

    Kok, D J; Papapoulos, S E; Blomen, L J; Bijvoet, O L

    1988-09-01

    The effects of several low and high molecular weight (mol wt) compounds on the kinetics of calcium oxalate crystallization were examined using a seeded crystal growth method in which the solubility, the growth and the agglomeration of calcium oxalate crystals were measured as three separate and system-independent parameters. Citrate, magnesium, phosphate, pyrophosphate, chondroitinsulphate, pentosanpolysulphate and heparin were tested in a wide range of concentrations. The solubility of calcium oxalate crystals was increased only by citrate and magnesium. The crystal growth was inhibited by all compounds tested, but those with the high mol wt had the greatest effect at low concentrations. In contrast, inhibition of crystal agglomeration was achieved only by the low mol wt compounds; citrate was found to be the most potent inhibitor at concentrations likely to be present in normal urine. The high mol wt substances, despite their potent crystal growth inhibitory activity, had no effect on agglomeration. The results show that growth and agglomeration of calcium oxalate crystals are separate processes which are differently modulated by various compounds. They further provide a possible explanation for the pathogenetic role of citrate in hypocitraturic renal stone disease. PMID:2459439

  19. Triamterene and renal stone formation: the influence of triamterene and triamterene stones on calcium oxalate crystallization.

    PubMed

    White, D J; Nancollas, G H

    1987-02-01

    A constant composition method has been used to compare the effects of triamterene renal stone material, synthetic triamterene precipitates, and soluble triamterene on the nucleation and crystallization kinetics of calcium oxalate in aqueous solution in vitro. Crystallization studies have been carried out with the concentrations of calcium and oxalate ions maintained constant by the potentiometrically controlled addition of concentrated reagent solutions containing these ions. Triamterene renal stones were found to be much less effective than synthetic triamterene towards promoting the nucleation and crystallization of calcium oxalate from supersaturated solution. Renal stones composed of triamterene and matrix did not significantly enhance the deposition of calcium oxalate compared to nonseeded controls. The triamterene stones were also found to be ineffective in promoting calcium oxalate crystallization compared to other precipitates thought to be involved in the etiology of stone disease such as calcium hydroxyapatite. For stones of mixed triamterene/calcium oxalate composition, the enhancement of the nucleation and crystallization of calcium oxalate was directly related to the calcium oxalate content of the stone seed material. The presence of soluble triamterene or its metabolites in solution did not influence the crystallization kinetics of pure calcium oxalate seed materials. The results of this study indicate that triamterene in stones does not significantly contribute to further stone development through the enhancement of calcium oxalate crystallization processes. PMID:3105837

  20. Regulation by macromolecules of calcium oxalate crystal aggregation in stone formers.

    PubMed

    Wesson, J A; Ganne, V; Beshensky, A M; Kleinman, J G

    2005-06-01

    Based on the structure of kidney stones, it is likely that they form as aggregations of preformed crystals, mostly calcium oxalate monohydrate (COM). In this study, we examined the ability of a macromolecular mixture isolated from the urine of normal individuals and stone formers to inhibit aggregation of preformed COM seed crystals in a simple ionic solution using measurements of changes in the particle size distribution (PSD) of preformed COM crystal aggregates. We also examined the effect in this assay of a number of synthetic homopolymers, naturally occurring urine macromolecules, and binary mixtures thereof. The macromolecular mixtures from urine of normals and most stone formers reduced the degree of aggregation of the seed crystals, whereas 22% of stone former urine macromolecules either did not disaggregate or actually promoted further aggregation. Stone formers within one family shared this property, but a non-stone forming sibling did not. Polyanions, either synthetic or naturally occurring, induced disaggregation to an extent similar to that exhibited by normal urine macromolecules, while polycations had no effect on the PSD. However, mixing a polyanion, either poly-aspartate or osteopontin, with the polycation poly-arginine, changed their behavior from disaggregation to aggregation promotion. The disaggregating behavior of normal urinary macromolecules provides a defense against aggregation, but a minority of stone forming individuals lacks this defense, which may contribute to stone formation. PMID:15864572

  1. Calcium oxalate monohydrate crystals internalized into renal tubular cells are degraded and dissolved by endolysosomes.

    PubMed

    Chaiyarit, Sakdithep; Singhto, Nilubon; Thongboonkerd, Visith

    2016-02-25

    Interaction between calcium oxalate crystals and renal tubular cells has been recognized as one of the key mechanisms for kidney stone formation. While crystal adhesion and internalization have been extensively investigated, subsequent phenomena (i.e. crystal degradation and dissolution) remained poorly understood. To explore these mechanisms, we used fluorescein isothiocyanate (FITC)-labelled calcium oxalate monohydrate (COM) crystals (1000 μg/ml of crystals/culture medium) to confirm crystal internalization into MDCK (Type II) renal tubular cells after exposure to the crystals for 1 h and to trace the internalized crystals. Crystal size, intracellular and extracellular fluorescence levels were measured using a spectrofluorometer for up to 48 h after crystal internalization. Moreover, markers for early endosome (Rab5), late endosome (Rab7) and lysosome (LAMP-2) were examined by laser-scanning confocal microscopy. Fluorescence imaging and flow cytometry confirmed that FITC-labelled COM crystals were internalized into MDCK cells (14.83 ± 0.85%). The data also revealed a reduction of crystal size in a time-dependent manner. In concordance, intracellular and extracellular fluorescence levels were decreased and increased, respectively, indicating crystal degradation/dissolution inside the cells and the degraded products were eliminated extracellularly. Moreover, Rab5 and Rab7 were both up-regulated and were also associated with the up-regulated LAMP-2 to form large endolysosomes in the COM-treated cells at 16-h after crystal internalization. We demonstrate herein, for the first time, that COM crystals could be degraded/dissolved by endolysosomes inside renal tubular cells. These findings will be helpful to better understand the crystal fate and protective mechanism against kidney stone formation. PMID:26748311

  2. [Components of Urinary Nanocrystals and Their Influence on Formation of Calcium Oxalate Stones].

    PubMed

    Li, Yu-bao; Wen, Xiao-ling; Xue, Jun-fa; Ouyang, Jian-ming

    2015-08-01

    High-resolution transmission electron microscopy, X-ray diffraction, selected area electron diffraction (SAED), and energy dispersive spectroscopy (EDS) were accurately performed to analyze the components of nanocrystals in the urine of patients with calcium oxalate (CaOx) stones. XRD, SAED and FFT detected the presence of calcium oxalate monohydrate (COM), uric acid (UA), and calcium phosphate (CaP). EDS detected the elements of C, O, Ca, with a small amount of N and P. These results showed that the main components of urinary nanocrystals were COM, with a small amount UA and phosphate. HRTEM observation showed that the particle size of urinary nanocrystals was dozens of nanometers. The result was consistent with the calculation by Debye-Scherrer equation. When the urine was filtered through a microporous membrane of 0.45, 1.2, and 3 ?m, respectively, the number of diffraction peaks of the obtained urine crystallites increased with the increased pore size, indicating the increase of urinary crystallite species. Crystal nucleation, growth, aggregation, and adhesion of crystals to the renal epithelial cells are important processes for CaOx stone formation. The presence of a large amount of COM crystals in patients' urine is a critical factor for CaOx stones formation. Nano UA and CaP crystallite can induce the CaOx stone formation as central nidus. PMID:26672305

  3. Herbal extracts of Tribulus terrestris and Bergenia ligulata inhibit growth of calcium oxalate monohydrate crystals in vitro

    NASA Astrophysics Data System (ADS)

    Joshi, V. S.; Parekh, B. B.; Joshi, M. J.; Vaidya, A. B.

    2005-02-01

    A large number of people in this world are suffering from urinary stone problem. Calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) containing stones (calculi) are commonly found. In the present study, COM crystals were grown by a double diffusion gel growth technique using U-tubes. The gel was prepared from hydrated sodium metasilicate solution. The gel framework acts like a three-dimensional crucible in which the crystal nuclei are delicately held in the position of their formation, and nutrients are supplied for the growth. This technique can be utilized as a simplified screening static model to study the growth, inhibition and dissolution of urinary stones in vitro. The action of putative litholytic medicinal plants, Tribulus terrestris Linn. ( T.t) and Bergenia ligulata Linn. ( B.l.), has been studied in the growth of COM crystals. Tribulus terrestris and Bergenia ligulata are commonly used as herbal medicines for urinary calculi in India. To verify the inhibitive effect, aqueous extracts of Tribulus terrestris and Bergenia ligulata were added along with the supernatant solutions. The growth was measured and compared, with and without the aqueous extracts. Inhibition of COM crystal growth was observed in the herbal extracts. Maximum inhibition was observed in Bergenia ligulata followed by Tribulus terrestris. The results are discussed.

  4. Effect of alkalinization on calcium oxalate monohydrate calculi during extracorporeal shock wave lithotripsy: in vivo experiments.

    PubMed

    Vandeursen, H; De Ridder, D; Demeulenaere, R; Pittomvils, G; Boving, R; Baert, L

    1992-01-01

    Previous in vitro experiments demonstrated the reduced microhardness of calcium oxalate monohydrate (COM) calculi, relative to dry values, when saturated with an alkaline solution (pH = 9.5). Nineteen patients with a COM calculus in the distal ureter which had been resistant to prior extracorporeal shock wave lithotripsy in situ, were treated when the stone was surrounded by alkaline urine. The urine of 14 patients was alkalinized orally by administration of acetazolamine and citrate solution; in 5 other patients direct percutaneous irrigation of sodium bicarbonate via a nephrostomy tube was carried out. The urinary pH just before lithotripsy was greater than or equal to 9 in 17/19 patients. 4,000 shock waves, averaging 18.1 kV generated by the Siemens Lithostar, were delivered onto the calculus. No significant increase of comminution rate was apparent at radiographic control immediately after the treatment and only in half of the cases was evacuation obtained within 3 months. PMID:1316663

  5. Specific Adsorption of Osteopontin and Synthetic Polypeptides to Calcium Oxalate Monohydrate Crystals

    PubMed Central

    Taller, Adam; Grohe, Bernd; Rogers, Kem A.; Goldberg, Harvey A.; Hunter, Graeme K.

    2007-01-01

    Protein-crystal interactions are known to be important in biomineralization. To study the physicochemical basis of such interactions, we have developed a technique that combines confocal microscopy of crystals with fluorescence imaging of proteins. In this study, osteopontin (OPN), a protein abundant in urine, was labeled with the fluorescent dye AlexaFluor-488 and added to crystals of calcium oxalate monohydrate (COM), the major constituent of kidney stones. In five to seven optical sections along the z axis, scanning confocal microscopy was used to visualize COM crystals and fluorescence imaging to map OPN adsorbed to the crystals. To quantify the relative adsorption to different crystal faces, fluorescence intensity was measured around the perimeter of the crystal in several sections. Using this method, it was shown that OPN adsorbs with high specificity to the edges between {100} and {121} faces of COM and much less so to {100}, {121}, or {010} faces. By contrast, poly-L-aspartic acid adsorbs preferentially to {121} faces, whereas poly-L-glutamic acid adsorbs to all faces approximately equally. Growth of COM in the presence of rat bone OPN results in dumbbell-shaped crystals. We hypothesize that the edge-specific adsorption of OPN may be responsible for the dumbbell morphology of COM crystals found in human urine. PMID:17496021

  6. Specific adsorption of osteopontin and synthetic polypeptides to calcium oxalate monohydrate crystals.

    PubMed

    Taller, Adam; Grohe, Bernd; Rogers, Kem A; Goldberg, Harvey A; Hunter, Graeme K

    2007-09-01

    Protein-crystal interactions are known to be important in biomineralization. To study the physicochemical basis of such interactions, we have developed a technique that combines confocal microscopy of crystals with fluorescence imaging of proteins. In this study, osteopontin (OPN), a protein abundant in urine, was labeled with the fluorescent dye AlexaFluor-488 and added to crystals of calcium oxalate monohydrate (COM), the major constituent of kidney stones. In five to seven optical sections along the z axis, scanning confocal microscopy was used to visualize COM crystals and fluorescence imaging to map OPN adsorbed to the crystals. To quantify the relative adsorption to different crystal faces, fluorescence intensity was measured around the perimeter of the crystal in several sections. Using this method, it was shown that OPN adsorbs with high specificity to the edges between {100} and {121} faces of COM and much less so to {100}, {121}, or {010} faces. By contrast, poly-L-aspartic acid adsorbs preferentially to {121} faces, whereas poly-L-glutamic acid adsorbs to all faces approximately equally. Growth of COM in the presence of rat bone OPN results in dumbbell-shaped crystals. We hypothesize that the edge-specific adsorption of OPN may be responsible for the dumbbell morphology of COM crystals found in human urine. PMID:17496021

  7. Proteome changes in human monocytes upon interaction with calcium oxalate monohydrate crystals.

    PubMed

    Singhto, Nilubon; Sintiprungrat, Kitisak; Sinchaikul, Supachok; Chen, Shui-Tein; Thongboonkerd, Visith

    2010-08-01

    Monocytic infiltration in renal interstitium is commonly found surrounding the site of calcium oxalate (CaOx) crystal deposition in the kidney. Monocytes are supposed to eliminate the deposited crystals. However, effects of CaOx crystals on the infiltrating monocytes remain unknown. Therefore, this study investigated the altered cellular proteome of human monocytes in response to interaction with CaOx monohydrate (COM) crystals. After 24-h culture with or without 100 microg/mL COM crystals, U937 cells were harvested and subjected to 2-DE analysis with Deep Purple fluorescence staining (n = 5 gels/group; each was derived from independent culture). Spot matching, quantitative intensity analysis, and statistics revealed 22 differentially expressed proteins (9 up-regulated and 13 down-regulated proteins), which were successfully identified by Q-TOF MS and MS/MS analyses, including those involved in cell cycle, cellular structure, carbohydrate metabolism, lipid metabolism, mRNA processing, and protein synthesis, stabilization, and degradation. Randomly selected changes [up-regulated ALG-2 interacting protein 1 (Alix), elongation factor-2 (EF-2), and down-regulated beta-actin] were confirmed by Western blot analysis. Our data may help to understand how monocytes interact with COM crystals. These processes are proposed to cause subsequent inflammatory response in kidney stone disease through oxidative stress pathway(s). PMID:20527803

  8. Modulation of calcium oxalate monohydrate crystallization by citrate through selective binding to atomic steps

    SciTech Connect

    Qiu, S R; Wierzbicki, A; Salter, E A; Zepeda, S; Orme, C A; Hoyer, J R; Nancollas, G H; Cody, A M; De Yoreo, J J

    2004-10-19

    The majority of human kidney stones are composed primarily of calcium oxalate monohydrate (COM) crystals. Thus, determining the molecular mechanisms by which urinary constituents modulate calcium oxalate crystallization is crucial for understanding and controlling urolithiassis in humans. A comprehensive molecular-scale view of COM shape modification by citrate, a common urinary constituent, obtained through a combination of in situ atomic force microscopy (AFM) and molecular modeling is now presented. We show that citrate strongly influences the growth morphology and kinetics on the (-101) face but has much lower effect on the (010) face. Moreover, binding energy calculations show that the strength of the citrate-COM interaction is much greater at steps than on terraces and is highly step-specific. The maximum binding energy, -166.5 kJ {center_dot} mol{sup -1}, occurs for the [101] step on the (-101) face. In contrast, the value is only -56.9 kJ {center_dot} mol-1 for the [012] step on the (010) face. The binding energies on the (-101) and (010) terraces are also much smaller, -65.4 and -48.9 kJ {center_dot} mol{sup -1} respectively. All other binding energies lie between these extremes. This high selectivity leads to preferential binding of citrate to the acute [101] atomic steps on the (-101) face. The strong citrate-step interactions on this face leads to pinning of all steps, but the anisotropy in interaction strength results in anisotropic reductions in step kinetics. These anisotropic changes in step kinetics are, in turn, responsible for changes in the shape of macroscopic COM crystals. Thus, the molecular scale growth morphology and the bulk crystal habit in the presence of citrate are similar, and the predictions of molecular simulations are fully consistent with the experimental observations.

  9. An understanding of renal stone development in a mixed oxalate-phosphate system.

    PubMed

    Guan, Xiangying; Wang, Lijun; Dosen, Anja; Tang, Ruikang; Giese, Rossman F; Giocondi, Jennifer L; Orme, Christine A; Hoyer, John R; Nancollas, George H

    2008-07-15

    The in vivo formation of calcium oxalate concretions having calcium phosphate nidi is simulated in an in vitro (37 degrees C, pH 6.0) dual constant composition (DCC) system undersaturated (sigma DCPD = -0.330) with respect to brushite (DCPD, CaHPO 4 . 2H 2O) and slightly supersaturated (sigma COM = 0.328) with respect to calcium oxalate monohydrate (COM, CaC2O4 . H2O). The brushite dissolution provides calcium ions that raise the COM supersaturation, which is heterogeneously nucleated either on or near the surface of the dissolving calcium phosphate crystals. The COM crystallites may then aggregate, simulating kidney stone formation. Interestingly, two intermediate phases, anhydrous dicalcium phosphate (monetite, CaHPO4) and calcium oxalate trihydrate (COT), are also detected by X-ray diffraction during this brushite-COM transformation. In support of clinical observations, the results of these studies demonstrate the participation of calcium phosphate phases in COM crystallization providing a possible physical chemical mechanism for kidney stone formation. PMID:18557638

  10. Elemental Content of Calcium Oxalate Stones from a Canine Model of Urinary Stone Disease

    PubMed Central

    Killilea, David W.; Westropp, Jodi L.; Shiraki, Ryoji; Mellema, Matthew; Larsen, Jennifer; Kahn, Arnold J.; Kapahi, Pankaj; Chi, Thomas; Stoller, Marshall L.

    2015-01-01

    One of the most common types of urinary stones formed in humans and some other mammals is composed of calcium oxalate in ordered hydrated crystals. Many studies have reported a range of metals other than calcium in human stones, but few have looked at stones from animal models such as the dog. Therefore, we determined the elemental profile of canine calcium oxalate urinary stones and compared it to reported values from human stones. The content of 19 elements spanning 7-orders of magnitude was quantified in calcium oxalate stones from 53 dogs. The elemental profile of the canine stones was highly overlapping with human stones, indicating similar inorganic composition. Correlation and cluster analysis was then performed on the elemental profile from canine stones to evaluate associations between the elements and test for potential subgrouping based on elemental content. No correlations were observed with the most abundant metal calcium. However, magnesium and sulfur content correlated with the mineral hydration form, while phosphorous and zinc content correlated with the neuter status of the dog. Inter-elemental correlation analysis indicated strong associations between barium, phosphorous, and zinc content. Additionally, cluster analysis revealed subgroups within the stones that were also based primarily on barium, phosphorous, and zinc. These data support the use of the dog as a model to study the effects of trace metal homeostasis in urinary stone disease. PMID:26066810

  11. Dual roles of brushite crystals in calcium oxalate crystallization provide physicochemical mechanisms underlying renal stone formation.

    PubMed

    Tang, R; Nancollas, G H; Giocondi, J L; Hoyer, J R; Orme, C A

    2006-07-01

    Calcium oxalate monohydrate (COM) crystals are the major mineral component of most kidney stones, and thus have an important role in chronic human disease. However, the physicochemical mechanisms leading to calcium oxalate (CaOx) stone disease are only partially defined. As spontaneous precipitation of CaOx is rare under renal conditions, an alternative pathway for CaOx crystallization seems necessary to resolve this central issue. We performed kinetic studies using the dual constant composition method to simultaneously analyze the crystallization of COM and brushite, the form of calcium phosphate that is most readily formed in the typical slightly acidic urinary milieu. These studies were supported by parallel analysis by scanning electron and atomic force microscopy. In these studies, mineralization of a thermodynamically stable phase (COM) was induced by the presence of brushite, a more readily precipitated inorganic phase. Furthermore, once formed, the COM crystals grew at the expense of brushite crystals causing the dissolution of the brushite crystals. These studies show that brushite may play crucial roles in the formation of COM crystals. The definition of these two roles for brushite thereby provides physicochemical explanations for the initiation of COM crystallization and also for the relative paucity of calcium phosphate detected in the majority of CaOx renal stones. PMID:16641926

  12. Citrate, not phosphate, can dissolve calcium oxalate monohydrate crystals and detach these crystals from renal tubular cells.

    PubMed

    Chutipongtanate, Somchai; Chaiyarit, Sakdithep; Thongboonkerd, Visith

    2012-08-15

    Dissolution therapy of calcium oxalate monohydrate (COM) kidney stone disease has not yet been implemented due to a lack of well characterized COM dissolution agents. The present study therefore aimed to identify potential COM crystal dissolution compounds. COM crystals were treated with deionized water (negative control), 5 mM EDTA (positive control), 5 mM sodium citrate, or 5mM sodium phosphate. COM crystal dissolution activities of these compounds were evaluated by phase-contrast and video-assisted microscopic examinations, semi-quantitative analysis of crystal size, number and total mass, and spectrophotometric oxalate-dissolution assay. In addition, effects of these compounds on detachment of COM crystals, which adhered tightly onto renal tubular cell surface, were also investigated. The results showed that citrate, not phosphate, had a significant dissolution effect on COM crystals as demonstrated by significant reduction of crystal size (approximately 37% decrease), crystal number (approximately 53% decrease) and total crystal mass (approximately 72% decrease) compared to blank and negative controls. Spectrophotometric oxalate-dissolution assay successfully confirmed the COM crystal dissolution property of citrate. Moreover, citrate could detach up to 85% of the adherent COM crystals from renal tubular cell surface. These data indicate that citrate is better than phosphate for dissolution and detachment of COM crystals. PMID:22713548

  13. Inhibition of calcium oxalate monohydrate growth by citrate and the effect of the background electrolyte

    NASA Astrophysics Data System (ADS)

    Weaver, Matthew L.; Qiu, S. Roger; Hoyer, John R.; Casey, William H.; Nancollas, George H.; De Yoreo, James J.

    2007-08-01

    Pathological mineralization is a common phenomenon in broad range of plants and animals. In humans, kidney stone formation is a well-known example that afflicts approximately 10% of the population. Of the various calcium salt phases that comprise human kidney stones, the primary component is calcium oxalate monohydrate (COM). Citrate, a naturally occurring molecule in the urinary system and a common therapeutic agent for treating stone disease, is a known inhibitor of COM. Understanding the physical mechanisms of citrate inhibition requires quantification of the effects of both background electrolytes and citrate on COM step kinetics. Here we report the results of an in situ AFM study of these effects, in which we measure the effect of the electrolytes LiCl, NaCl, KCl, RbCl, and CsCl, and the dependence of step speed on citrate concentration for a range of COM supersaturations. We find that varying the background electrolyte results in significant differences in the measured step speeds and in step morphology, with KCl clearly producing the smallest impact and NaCl the largest. The kinetic coefficient for the former is nearly three times larger than for the latter, while the steps change from smooth to highly serrated when KCl is changed to NaCl. The results on the dependence of step speed on citrate concentration show that citrate produces a dead zone whose width increases with citrate concentration as well as a continual reduction in kinetic coefficient with increasing citrate level. We relate these results to a molecular-scale view of inhibition that invokes a combination of kink blocking and step pinning. Furthermore, we demonstrate that the classic step-pinning model of Cabrera and Vermilyea (C-V model) does an excellent job of predicting the effect of citrate on COM step kinetics provided the model is reformulated to more realistically account for impurity adsorption, include an expression for the Gibbs-Thomson effect that is correct for all supersaturations, and take into account a reduction in kinetic coefficient through kink blocking. The detailed derivation of this reformulated C-V model is presented and the underlying materials parameters that control its impact are examined. Despite the fact that the basic C-V model was proposed nearly 50 years ago and has seen extensive theoretical treatment, this study represents the first quantitative and molecular scale experimental confirmation for any crystal system.

  14. Calcium Oxalate Stones Are Frequently Found Attached to Randall's Plaque

    NASA Astrophysics Data System (ADS)

    Matlaga, Brian R.; Williams, James C.; Evan, Andrew P.; Lingeman, James E.

    2007-04-01

    The exact mechanisms of the crystallization processes that occur during the formation of calcium oxalate calculi are controversial. Over six decades ago, Alexander Randall reported on a series of cadaveric renal units in which he observed calcium salt deposits on the tips of the renal papilla. Randall hypothesized that these deposits, eponymously termed Randall's plaque, would be the ideal site for stone formation, and indeed in a number of specimens he noted small stones attached to the papillae. With the recent advent of digital endoscopic imaging and micro computerized tomography (CT) technology, it is now possible to inspect the renal papilla of living, human stone formers and to study the attached stone with greater scrutiny.

  15. Calcium Oxalate Stones Are Frequently Found Attached to Randall's Plaque

    SciTech Connect

    Matlaga, Brian R.

    2007-04-05

    The exact mechanisms of the crystallization processes that occur during the formation of calcium oxalate calculi are controversial. Over six decades ago, Alexander Randall reported on a series of cadaveric renal units in which he observed calcium salt deposits on the tips of the renal papilla. Randall hypothesized that these deposits, eponymously termed Randall's plaque, would be the ideal site for stone formation, and indeed in a number of specimens he noted small stones attached to the papillae. With the recent advent of digital endoscopic imaging and micro computerized tomography (CT) technology, it is now possible to inspect the renal papilla of living, human stone formers and to study the attached stone with greater scrutiny.

  16. Theoretical calculation of zero field splitting parameters of Cr3+ doped ammonium oxalate monohydrate

    NASA Astrophysics Data System (ADS)

    Kripal, Ram; Yadav, Awadhesh Kumar

    2015-06-01

    Zero field splitting parameters (ZFSPs) D and E of Cr3+ ion doped ammonium oxalate monohydrate (AOM) are calculated with formula using the superposition model. The theoretically calculated ZFSPs for Cr3+ in AOM crystal are compared with the experimental value obtained by electron paramagnetic resonance (EPR). Theoretical ZFSPs are in good agreement with the experimental ones. The energy band positions of optical absorption spectra of Cr3+ in AOM crystal calculated with CFA package are in good match with the experimental values.

  17. Selective inclusion of proteins into urinary calcium oxalate crystals: comparison between stone-prone and stone-free population groups

    NASA Astrophysics Data System (ADS)

    Webber, D.; Rodgers, A. L.; Sturrock, E. D.

    2003-11-01

    This study investigated whether incorporation of proteins into calcium oxalate urinary crystals is different in the black and white populations in South Africa and whether such differences could provide insight into the former group's remarkably low stone incidence. CaOx monohydrate (COM) and dihydrate (COD) crystals were precipitated from each group's urine after adjustment of the calcium concentrations to 0.5 and 12 mmol/l, respectively. Crystals were characterised by X-ray powder diffraction and scanning electron microscopy. Intracrystalline proteins were analysed by SDS-PAGE and immunodetected for urinary prothrombin fragment 1 (UPTF1) and osteopontin. Crystals precipitated from the black and white groups' control urines comprised mainly COM and COD, respectively. In both race groups UPTF1 was the major protein included in pure COM crystals while in pure COD it was osteopontin, but in the black group osteopontin was also included in COM. The black group's urine crystals incorporated significantly more intracrystalline protein. Selective inclusion of UPTF1 and osteopontin may be due to the unique crystal structure of COM and COD and the proteins' conformation at the different calcium concentrations at which these hydrates precipitate. The greater amount of intracrystalline inhibitory protein in the black group may be a factor in their low stone incidence.

  18. Nanouric acid or nanocalcium phosphate as central nidus to induce calcium oxalate stone formation: a high-resolution transmission electron microscopy study on urinary nanocrystallites

    PubMed Central

    Gao, Jie; Xue, Jun-Fa; Xu, Meng; Gui, Bao-Song; Wang, Feng-Xin; Ouyang, Jian-Ming

    2014-01-01

    Purpose This study aimed to accurately analyze the relationship between calcium oxalate (CaOx) stone formation and the components of urinary nanocrystallites. Method High-resolution transmission electron microscopy (HRTEM), selected area electron diffraction, fast Fourier transformation of HRTEM, and energy dispersive X-ray spectroscopy were performed to analyze the components of these nanocrystallites. Results The main components of CaOx stones are calcium oxalate monohydrate and a small amount of dehydrate, while those of urinary nanocrystallites are calcium oxalate monohydrate, uric acid, and calcium phosphate. The mechanism of formation of CaOx stones was discussed based on the components of urinary nanocrystallites. Conclusion The formation of CaOx stones is closely related both to the properties of urinary nanocrystallites and to the urinary components. The combination of HRTEM, fast Fourier transformation, selected area electron diffraction, and energy dispersive X-ray spectroscopy could be accurately performed to analyze the components of single urinary nanocrystallites. This result provides evidence for nanouric acid and/or nanocalcium phosphate crystallites as the central nidus to induce CaOx stone formation. PMID:25258530

  19. Oxalate-degrading microorganisms or oxalate-degrading enzymes: which is the future therapy for enzymatic dissolution of calcium-oxalate uroliths in recurrent stone disease?

    PubMed

    Peck, Ammon B; Canales, Benjamin K; Nguyen, Cuong Q

    2016-02-01

    Renal urolithiasis is a pathological condition common to a multitude of genetic, physiological and nutritional disorders, ranging from general hyperoxaluria to obesity. The concept of quickly dissolving renal uroliths via chemolysis, especially calcium-oxalate kidney stones, has long been a clinical goal, but yet to be achieved. Over the past 25 years, there has been a serious effort to examine the prospects of using plant and microbial oxalate-degrading enzymes known to catabolize oxalic acid and oxalate salts. While evidence is emerging that bacterial probiotics can reduce recurrent calcium-oxalate kidney stone disease by lowering systemic hyperoxaluria, the possible use of free oxalate-degrading enzyme therapy remains a challenge with several hurdles to overcome before reaching clinical practice. PMID:26645869

  20. High-throughput platform for design and screening of peptides as inhibitors of calcium oxalate monohydrate crystallization

    NASA Astrophysics Data System (ADS)

    Farmanesh, Sahar; Chung, Jihae; Chandra, Divya; Sosa, Ricardo D.; Karande, Pankaj; Rimer, Jeffrey D.

    2013-06-01

    Crystal growth modifiers present a versatile tool for controlling crystal shape and size. Our work described here focuses on the design and screening of short peptides as inhibitors of calcium oxalate monohydrate (COM) crystals using high-throughput approaches. We designed a small library of 13 peptides containing Ala and Asp amino acids arranged in varying sequences that mimic ubiquitous motifs in natural calcium-binding proteins. Peptides were screened using a quick assay to measure their efficacy for inhibiting COM crystallization. Our results show that subtle variations in the placement of Ala and Asp residues in the peptide sequence can have a profound effect on their inhibition potential. We were able to discover peptide sequences that inhibit COM crystallization more effectively than some of the well-known COM inhibitors, such as citrate. Our results also demonstrate that peptides can be engineered to bind to specific faces of COM crystals. Peptide sequences identified in this work are promising candidates for further development as therapies for biomineral-related diseases, such as kidney stone disease. Collectively, our work establishes new paradigms for the design, synthesis, and screening of peptides for controlling crystal habit with the potential to impact a variety of fields, including drug discovery, advanced materials, catalysis and separations.

  1. EPR, optical and modeling of Mn2+ doped sarcosinium oxalate monohydrate

    NASA Astrophysics Data System (ADS)

    Kripal, Ram; Singh, Manju

    2015-01-01

    Electron paramagnetic resonance (EPR) study of Mn2+ ions doped in sarcosinium oxalate monohydrate (SOM) single crystal is done at liquid nitrogen temperature (LNT). EPR spectrum shows a bunch of five fine structure lines and further they split into six hyperfine components. Only one interstitial site was observed. With the help of EPR spectra the spin Hamiltonian parameters including zero field splitting (ZFS) parameters are evaluated. The optical absorption study at room temperature is also done in the wavelength range 195-1100 nm. From this study cubic crystal field splitting parameter, Dq = 730 cm-1 and Racah inter-electronic repulsion parameters B = 792 cm-1, C = 2278 cm-1 are determined. ZFS parameters D and E are also calculated using crystal field parameters from superposition model and microscopic spin Hamiltonian theory. The calculated ZFS parameter values are in good match with the experimental values obtained by EPR.

  2. EPR, optical and modeling of Mn(2+) doped sarcosinium oxalate monohydrate.

    PubMed

    Kripal, Ram; Singh, Manju

    2015-01-25

    Electron paramagnetic resonance (EPR) study of Mn(2+) ions doped in sarcosinium oxalate monohydrate (SOM) single crystal is done at liquid nitrogen temperature (LNT). EPR spectrum shows a bunch of five fine structure lines and further they split into six hyperfine components. Only one interstitial site was observed. With the help of EPR spectra the spin Hamiltonian parameters including zero field splitting (ZFS) parameters are evaluated. The optical absorption study at room temperature is also done in the wavelength range 195-1100 nm. From this study cubic crystal field splitting parameter, Dq=730 cm(-1) and Racah inter-electronic repulsion parameters B=792 cm(-1), C=2278 cm(-1) are determined. ZFS parameters D and E are also calculated using crystal field parameters from superposition model and microscopic spin Hamiltonian theory. The calculated ZFS parameter values are in good match with the experimental values obtained by EPR. PMID:25150437

  3. Rate constants of flipping, and shielding tensors of stationary water molecules in potassium oxalate monohydrate

    NASA Astrophysics Data System (ADS)

    Schuff, N.; Haeberlen, U.

    As in most other hydrates the water molecules in potassium oxalate monohydrate (KOMH) are undergoing rapid so-called flip motions at normal ambient temperature. Under such conditions only motionally averaged shielding tensors are accessible to measurement. Cooling crystals of KOMH to T ? 250 K slows down the flip rate sufficiently to allow the measurement of proton shielding tensors of essentially stationary water molecules. The application of fine-narrowing multiple-pulse sequences is mandatory. The most shielded direction of the proton, ez, is found to lie very close to the internuclear vector connecting the hydrogen bonded water and oxalate oxygens. The angle subtended by ez and the O sbnd H bond direction is, however, as large as 6.6. The data suggest that the perpendicular to the molecular plane is the least shielded direction in the free water molecule. The rate constant of the flips is measured by analyzing the lineshape of multiple-pulse spectra. The measurable range of the rate constant is from about 10 2 s -1 (slow exchange limit) to 10 5 s -1 (fast exchange limit). The temperature dependence of the rate constant follows the Arrhenius relation with ?E = 15.4 kcal/mol and ? 0 = 2.2 10 15s -1.

  4. Use of a calcium tracer to detect stone increments in a rat calcium oxalate xenoplantation model

    PubMed Central

    WANG, SHUO; XU, QINGQUAN; HUANG, XIAOBO; LIN, JINGXING; WANG, JINXING; WANG, XIAOFENG

    2013-01-01

    The majority of urinary stones have been observed to grow by circular increments in the clinic and in animal studies. However, the mechanism of stone formation has not yet been elucidated. Marking the stone at specific time-points during the growth of the stone is likely to enable the clarification of the mechanisms behind lithogenesis. The objective of this study was to evaluate the role and efficacy of calcium-tracing fluorescence in the labeling of stone lamination in a rat calcium oxalate xenoplantation model. In the rat calcium oxalate xenoplantation model, human renal stone particles, extracted by percutaneous nephrolithotomy, were xenoplanted into the bladders of Wistar rats in a sterile manner. The rats received 1% ethylene glycol in their drinking water, starting from the day following the stone xenoplantation. Two weeks subsequent to this, three calcium-tracing fluorochromes, alizarin complexone, calcein and xylenol orange were administered by intraperitoneal injection. The newly-formed bladder stones were cut into slices and examined using light and fluorescence microscopy. The newly-formed bladder stones had a large variance in size, and circular increments were observed in the sections of the stones. The stones were successfully labeled with calcein and alizarin complexone, although calcein labeling provided superior results. However, the use of xylenol orange did not result in clear labeling. The calcium-tracing fluorochromes, calcein and alizarin complexone may be effectively used to label stone lamination in rat models. PMID:24137297

  5. Use of a calcium tracer to detect stone increments in a rat calcium oxalate xenoplantation model.

    PubMed

    Wang, Shuo; Xu, Qingquan; Huang, Xiaobo; Lin, Jingxing; Wang, Jinxing; Wang, Xiaofeng

    2013-10-01

    The majority of urinary stones have been observed to grow by circular increments in the clinic and in animal studies. However, the mechanism of stone formation has not yet been elucidated. Marking the stone at specific time-points during the growth of the stone is likely to enable the clarification of the mechanisms behind lithogenesis. The objective of this study was to evaluate the role and efficacy of calcium-tracing fluorescence in the labeling of stone lamination in a rat calcium oxalate xenoplantation model. In the rat calcium oxalate xenoplantation model, human renal stone particles, extracted by percutaneous nephrolithotomy, were xenoplanted into the bladders of Wistar rats in a sterile manner. The rats received 1% ethylene glycol in their drinking water, starting from the day following the stone xenoplantation. Two weeks subsequent to this, three calcium-tracing fluorochromes, alizarin complexone, calcein and xylenol orange were administered by intraperitoneal injection. The newly-formed bladder stones were cut into slices and examined using light and fluorescence microscopy. The newly-formed bladder stones had a large variance in size, and circular increments were observed in the sections of the stones. The stones were successfully labeled with calcein and alizarin complexone, although calcein labeling provided superior results. However, the use of xylenol orange did not result in clear labeling. The calcium-tracing fluorochromes, calcein and alizarin complexone may be effectively used to label stone lamination in rat models. PMID:24137297

  6. Ionic strength and ion ratio effects on the single crystal growth of calcium oxalate monohydrate

    SciTech Connect

    DeLong, J.D.; Briedis, D.M.

    1987-01-01

    Single crystal growth rates of calcium oxalate monohydrate, CaC/sub 2/O/sub 4/ . H/sub 2/O, were measured as a function of ionic strength and of calcium to oxalate free ion ratio. The photomicroscopic technique was used which allowed measurement of the growth rates of individual faces of single crystals. The amounts of reagents required to maintain a constant relative supersaturation of 3.7 for all experiments were determined using an iterative computer algorithm which allowed the use of various background electrolytes, ionic strength, and free ion ratios. For a range of ionic strengths of I = .0024 to 0.5 for each of the background electrolytes KCl, LiCl, and KClO/sub 4/, and a free ion ratio (Ca/sup 2+/)/(C/sub 2/O/sub 4//sup 2-/) = 1, facial growth rate showed a steady increase with ionic strength towards an asymptotic maximum. The curves of growth rate, R, versus ionic strength followed approximately the form R = k I/sup n/ with 0 < n < 1, suggesting a mechanism of growth enhancement with increasing ionic strength by compression of the electrical double layer at the crystal/solution interface. For a range of free ion ratios (Ca/sup 2+/)/(C/sub 2/O/sub 4//sup 2-/) = 0.01 to 100 and an ionic strength of I = 0.15 M, the observed growth rate showed a maximum at equimolar free ion conditions, with decreasing growth rates observed at lower and higher ion ratios. This growth rate maximum was not apparent under conditions with no added background electrolyte. These results indicate that relative supersaturation as usually used for crystal growth may not be the complete or appropriate driving force for describing electrolyte crystal growth.

  7. Specificity of growth inhibitors and their cooperative effects in calcium oxalate monohydrate crystallization.

    PubMed

    Farmanesh, Sahar; Ramamoorthy, Sriram; Chung, Jihae; Asplin, John R; Karande, Pankaj; Rimer, Jeffrey D

    2014-01-01

    The molecular recognition and interactions governing site-specific adsorption of growth inhibitors on crystal surfaces can be tailored in order to control the anisotropic growth rates and physical properties of crystalline materials. Here we examine this phenomenon in calcium oxalate monohydrate (COM) crystallization, a model system of calcification with specific relevance for pathological mineralization. We analyzed the effect of three putative growth inhibitors--chondroitin sulfate, serum albumin, and transferrin--using analytical techniques capable of resolving inhibitor-crystal interactions from interfacial to bulk scales. We observed that each inhibitor alters surface growth by adsorbing on to distinct steps emanating from screw dislocations on COM surfaces. Binding of inhibitors to different crystallographic faces produced morphological modifications that are consistent with classical mechanisms of layer-by-layer crystal growth inhibition. The site-specific adsorption of inhibitors on COM surfaces was confirmed by bulk crystallization, fluorescent confocal microscopy, and atomic force microscopy. Kinetic studies of COM growth at varying inhibitor concentrations revealed marked differences in their efficacy and potency. Systematic analysis of inhibitor combinations, quantified via the combination index, identified various binary pairings capable of producing synergistic, additive, and antagonistic effects. Collectively, our investigation of physiologically relevant biomolecules suggests potential roles of COM inhibitors in pathological crystallization and provides guiding principles for biomimetic design of molecular modifiers for applications in crystal engineering. PMID:24313314

  8. Can a dual-energy computed tomography predict unsuitable stone components for extracorporeal shock wave lithotripsy?

    PubMed Central

    Ahn, Sung Hoon; Oh, Tae Hoon

    2015-01-01

    Purpose To assess the potential of dual-energy computed tomography (DECT) to identify urinary stone components, particularly uric acid and calcium oxalate monohydrate, which are unsuitable for extracorporeal shock wave lithotripsy (ESWL). Materials and Methods This clinical study included 246 patients who underwent removal of urinary stones and an analysis of stone components between November 2009 and August 2013. All patients received preoperative DECT using two energy values (80 kVp and 140 kVp). Hounsfield units (HU) were measured and matched to the stone component. Results Significant differences in HU values were observed between uric acid and nonuric acid stones at the 80 and 140 kVp energy values (p<0.001). All uric acid stones were red on color-coded DECT images, whereas 96.3% of the nonuric acid stones were blue. Patients with calcium oxalate stones were divided into two groups according to the amount of monohydrate (calcium oxalate monohydrate group: monohydrate?90%, calcium oxalate dihydrate group: monohydrate<90%). Significant differences in HU values were detected between the two groups at both energy values (p<0.001). Conclusions DECT improved the characterization of urinary stone components and was a useful method for identifying uric acid and calcium oxalate monohydrate stones, which are unsuitable for ESWL. PMID:26366277

  9. Stone composition and metabolic status.

    PubMed

    Bibilash, B S; Vijay, Adarsh; Fazil Marickar, Y M

    2010-06-01

    This paper aims to study the correlation between biochemical risk factors of the stone former and the type of oxalate stone formed, namely calcium oxalate monohydrate (COM) and calcium oxalate dehydrate (COD). A retrospective study of 487 patients who had been attending the urinary stone clinic, Trivandrum during 1998-2007 was conducted. The stones retrieved from them were subjected to chemical analysis and FTIR spectrographic analysis. They were categorized into COM, COD, mixed COM+COD and others. Of 142 pure calcium oxalate stone patients, 87 were predominantly COM stone formers and 55 COD stone formers. Their metabolic status of 24 h urine and serum was assessed. The values of urine calcium, phosphorus, uric acid, magnesium, creatinine, oxalate, citric acid, sodium and potassium, serum values of calcium, phosphorus, uric acid, magnesium and creatinine and calculated values of creatinine clearance, tubular reabsorption of phosphate, calcium magnesium ratio and calcium oxalate ratio were recorded. Comparison was made between the COM stone group and the COD stone group. Patients forming COM stones had significantly higher mean values for urine calcium (P < 0.05), oxalate (P < 0.01) and magnesium (P < 0.05) levels and significantly lower level of urine calcium-oxalate ratio (P < 0.01) and urine calcium-magnesium ratio (P < 0.01) compared to COD stone forming patients. All other values failed to show significant difference. Patients, with higher urine oxalate, formed COM stones. Those with low magnesium (which is an inhibitor) formed more of COD stones. Urine calcium was high in both groups without showing significant variation from the mean. In patients with high calcium-oxalate and calcium-magnesium ratios, there is higher chance of forming a COD stone than COM. Identification of the crystallization pattern of the calcium stone will help in selecting treatment modalities. PMID:19921167

  10. CONTRASTING HISTOPATHOLOGY AND CRYSTAL DEPOSITS IN KIDNEYS OF IDIOPATHIC STONE FORMERS WHO PRODUCE HYDROXY APATITE, BRUSHITE, OR CALCIUM OXALATE STONES

    PubMed Central

    Evan, Andrew P; Lingeman, James E; Worcester, Elaine M; Sommer, Andre J; Phillips, Carrie L; Williams, James C; Coe, Fredric L

    2014-01-01

    Our previous work has shown that stone formers who form calcium phosphate (CaP) stones that contain any brushite (BRSF) have a distinctive renal histopathology and surgical anatomy when compared to idiopathic calcium oxalate stone formers (ICSF). Here we report on another group of idiopathic CaP stone formers, those forming stone containing primarily hydroxyapatite, in order to clarify in what ways their pathology differs from BRSF and ICSF. Eleven hydroxyapatite stone formers (HASF) (2 males, 9 females) were studied using intra-operative digital photography and biopsy of papillary and cortical regions to measure tissue changes associated with stone formation. Our main finding is that HASF and BRSF differ significantly from each other and that both differ greatly from ICSF. Both BRSF and ICSF patients have significant levels of Randalls plaque compared to HASF. Intra-tubular deposit number is greater in HASF than BRSF and non-existent in ICSF while deposit size is smaller in HASF than BRSF. Cortical pathology is distinctly greater in BRSF than HASF. Four attached stones were observed in HASF, three in 25 BRSF and 510 per ICSF patient. HASF and BRSF differ clinically in that both have higher average urine pH, supersaturation of CaP, and calcium excretion than ICSF. Our work suggests that HASF and BRSF are two distinct and separate diseases and both differ greatly from ICSF. PMID:24478243

  11. Distinguishing Characteristics of Idiopathic Calcium Oxalate Kidney Stone Formers with Low Amounts of Randall's Plaque

    PubMed Central

    Wang, Xiangling; Krambeck, Amy E.; Williams, James C.; Tang, Xiaojing; Rule, Andrew D.; Zhao, Fang; Bergstralh, Eric; Haskic, Zejfa; Edeh, Samuel; Holmes, David R.; Hernandez, Loren P. Herrera

    2014-01-01

    Background Overgrowth of calcium oxalate on Randall's plaque is a mechanism of stone formation among idiopathic calcium oxalate stone-formers (ICSFs). It is less clear how stones form when there is little or no plaque. Design, setting, participants, & measurements Participants were a consecutive cohort of ICSFs who underwent percutaneous nephroscopic papillary mapping in the kidney or kidneys containing symptomatic stones and a papillary tip biopsy from a representative calyx during a stone removal procedure between 2009 and 2013. The distribution of Randall's plaque coverage was analyzed and used to divide ICSFs into those with a high (?5%; mean, 10.5%; n=10) versus low (<5%; mean, 1.5%; n=32) amount of plaque coverage per papilla. Demographic and laboratory features were compared between these two groups. Results Low-plaque stone formers tended to be obese (50% versus 10%; P=0.03) and have a history of urinary tract infection (34% versus 0%; P=0.04). They were less likely to have multiple prior stone events (22% versus 80%; P=0.002) and had a lower mean 24-hour urine calcium excretion (18786 mg versus 29199 mg; P<0.01). Morphologically, stones from patients with low amounts of plaque lacked a calcium phosphate core by microcomputed tomography. Papillary biopsies from low plaque stone-formers revealed less interstitial and basement membrane punctate crystallization. Conclusions These findings suggest that other pathways independent of Randall's plaque may contribute to stone pathogenesis among a subgroup of ICSFs who harbor low amounts of plaque. PMID:25092598

  12. Mass spectroscopic characteristics of low molecular weight proteins extracted from calcium oxalate stones: preliminary study.

    PubMed

    Chen, Wen-Chi; Lai, Chien-Chen; Lai, Chein-Cheng; Tsai, Yuhsin; Tsai, Yu-Hsin; Lin, Wei-Yong; Tsai, Fuu-Jen

    2008-01-01

    It is believed that boundary compositions of matrix proteins might play a role in stone formation; however, few proteomic studies concerning matrix proteins in urinary stones have been conducted. In this study, we extracted low molecular weight proteins from calcium oxalate stones and measured their characteristic patterns by mass spectroscopy. A total of 10 stones were surgically removed from patients with urolithiasis. Proteins were extracted from the stones and identified by one-dimensional electrophoresis (sodium dodecyl sulfate buffer [SDS]-polyacrylamide gel electrophoresis [SDS-PAGE]). After in-gel digest, samples were analyzed by the surface-enhanced laser desorption ionization-time of flight (SELDI-TOF) technique. The peptide sequences were analyzed from the data of mass spectroscopy. Proteins were identified from Database Search (SwissProt Protein Database; Swiss Institute of Bioinformatics; http://www.expasy.org/sprot) on a MASCOT server (Matrix Science Ltd.; http://www.matrixscience.com). A total of three bands of proteins (27, 18, and 14 kDa) were identified from SDS-PAGE in each stone sample. A database search (SwissProt) on a MASCOT server revealed that the most frequently seen proteins from band 1 (27 kDa) were leukocyte elastase precursor, cathepsin G precursor, azurocidin precursor, and myeloblastin precursor (EC 3.4.21.76) (leukocyte proteinase 3); band 2 (18 kDa) comprised calgranulin B, eosinophil cationic protein precursor, and lysozyme C precursor; band 3 (14 kDa) showed neutrophil defensin 3 precursor, calgranulin A, calgranulin C, and histone H4. The modifications and deamidations found from the mass pattern of these proteins may provide information for the study of matrix proteins. Various lower molecular weight proteins can be extracted from calcium oxalate stones. The characteristic patterns and their functions of those proteins should be further tested to investigate their roles in stone formation. PMID:18200570

  13. Chemolysis of calcium oxalate stones: study in vitro and possible clinical application.

    PubMed

    Kustov, Andrey V; Shevyrin, Alexey A; Strel'nikov, Alexander I; Smirnov, Pavel R; Trostin, Vyacheslav N

    2012-06-01

    The flow cell modeling clinical conditions have been used to study the interaction between dilute chemolytic solutions and large calcium oxalate renal stones. The stone treatment with 5% disodium ethylenediaminetetraacetate aqueous solutions or citrate buffer are found not to provide notable disruption of the samples studied. The significant improvement is reached with the mixed compositions containing both natural and synthetic chelating reagents:citrate and ethylenediaminetetraacetate ions as well as an antibiotic. Description of the chemolytic irrigation, numerical results and their possible clinical application are the main topic of the present research. PMID:22089056

  14. Prophylactic effects of quercetin and hyperoside in a calcium oxalate stone forming rat model.

    PubMed

    Zhu, Wei; Xu, Yun-fei; Feng, Yuan; Peng, Bo; Che, Jian-ping; Liu, Min; Zheng, Jun-hua

    2014-12-01

    Quercetin and hyperoside (QH) are the two main constituents of the total flavone glycosides of Flos Abelmoschus manihot, which has been prescribed for treating chronic kidney disease for decades. This study aimed to investigate the effect of QH on calcium oxalate (CaOx) formation in ethylene glycol (EG)-fed rats. Rats were divided into three groups: an untreated stone-forming group, a QH-treated stone-forming group (20 mg/kg/day) and a potassium citrate-treated stone-forming group (potassium citrate was a worldwide-recognized calculi-prophylactic medicine). Ethylene glycol (0.5 %) was administered to the rats during the last week, and vitamin D3 was force-fed to induce hyperoxaluria and kidney calcium oxalate crystal deposition. 24 h urine samples were collected before and after inducing crystal deposits. Rats were killed and both kidneys were harvested after 3 weeks. Bisected kidneys were examined under a polarized light microscope for semi-quantification of the crystal-formation. The renal tissue superoxide dismutase and catalase levels were measured by Western blot. QH and potassium citrate have the ability to alkalinize urine. The number of crystal deposits decreased significantly in the QH-treated stone-forming group as compared to the other groups. Superoxide dismutase and catalase levels also increased significantly in the QH-treated stone-forming group, as compared with the untreated stone-forming group. QH administration has an inhibitory effect on the deposition of CaOx crystal in EG-fed rats and may be effective for preventing stone-forming disease. PMID:25085199

  15. AB152. Analysis of altered microRNA expression profile in calcium oxalate stone formation

    PubMed Central

    Liu, Zhuo; Jiang, Hongyang; Wang, Tao; Yang, Jun; Wang, Shaogang; Liu, Jihong; Yang, Weimin; Ye, Zhangqun

    2015-01-01

    Objective Calcium oxalate stones account for over 80% of urinary stones, while the molecular mechanism of its formation has been unclear. Hyperoxaluria plays an important role in the pathophysiological process of stone formation. The difference of miRNA expression profiles between experimental hyperoxaluric rats and normal rats is analyzed in our study, in order to find out the target genes and signaling pathways in the pathogenesis procedure of hyperoxaluria. Methods Feeding ethylene glycol and ammonium chloride to culture male experimental hyperoxaluric rats as the experimental group, and age-matched male rats were selected as the control group. The oxalate concentration of 24 hour urine of each experimental rat was measured, of which the three highest were selected for microarray test. MicroRNA microarray was applied to evaluate the expression difference between the two groups and screen miRNA whose fold change were above 2.0 or below 0.5. Quantitative real-time PCR (qRT-PCR) technology was used to validate the microarray results. Target prediction, Gene Ontology (GO) analysis and pathway analysis were applied to predict the potential roles of microRNAs in biological processes. Results There are 28 miRNAs differentially expressed with a more than 2.0-fold change. Among these miRNAs, 20 were up-regulated while 8 were down-regulated. After GO analysis and pathway analysis, the insulin resistance pathway and PI3K-Akt signaling pathway were associated with miRNA regulation. Conclusions This study identified differentially expressed miRNAs in hyperoxaluric rats, providing new insights into the role of miRNA in the formation of calcium oxalate stones.

  16. Chemical composition and binary mixture of human urinary stones using FT-Raman spectroscopy method

    NASA Astrophysics Data System (ADS)

    Selvaraju, R.; Raja, A.; Thiruppathi, G.

    2013-10-01

    In the present study the human urinary stones were observed in their different chemical compositions of calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate, struvite (magnesium ammonium phosphate), uric acid, cystine, oxammite (ammonium oxalate monohydrate), natroxalate (sodium oxalate), glushinkite (magnesium oxalate dihydrate) and moolooite (copper oxalate) were analyzed using Fourier Transform-Raman (FT-Raman) spectroscopy. For the quantitative analysis, various human urinary stone samples are used for ratios calculation of binary mixtures compositions such as COM/COD, HAP/COD, HAP/COD, Uric acid/COM, uric acid/COD and uric acid/HAP. The calibration curve is used for further analysis of binary mixture of human urinary stones. For the binary mixture calculation the various intensities bands at 1462 cm-1 (ICOM), 1473 cm-1 (ICOD), 961 cm-1 (IHAP) and 1282 cm-1 (IUA) were used.

  17. Chemical composition and binary mixture of human urinary stones using FT-Raman spectroscopy method.

    PubMed

    Selvaraju, R; Raja, A; Thiruppathi, G

    2013-10-01

    In the present study the human urinary stones were observed in their different chemical compositions of calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate, struvite (magnesium ammonium phosphate), uric acid, cystine, oxammite (ammonium oxalate monohydrate), natroxalate (sodium oxalate), glushinkite (magnesium oxalate dihydrate) and moolooite (copper oxalate) were analyzed using Fourier Transform-Raman (FT-Raman) spectroscopy. For the quantitative analysis, various human urinary stone samples are used for ratios calculation of binary mixtures compositions such as COM/COD, HAP/COD, HAP/COD, Uric acid/COM, uric acid/COD and uric acid/HAP. The calibration curve is used for further analysis of binary mixture of human urinary stones. For the binary mixture calculation the various intensities bands at 1462 cm(-1) (I(COM)), 1473 cm(-1) (I(COD)), 961 cm(-1) (I(HAP)) and 1282 cm(-1) (I(UA)) were used. PMID:23816485

  18. Renal papillary calcification and the development of calcium oxalate monohydrate papillary renal calculi: a case series study

    PubMed Central

    2013-01-01

    Background The objective of this study is to determine in a case series (four patients) how calcified deposits in renal papillae are associated with the development of calcium oxalate monohydrate (COM) papillary calculi. Methods From the recently collected papillary calculi, we evaluated retrospectively patients, subjected to retrograde ureteroscopy, with COM papillary lithiasis. Results The COM papillary calculi were found to result from subepithelial injury. Many of these lesions underwent calcification by hydroxyapatite (HAP), with calculus morphology and the amount of HAP in the concave zone dependent on the location of the calcified injury. Most of these HAP deposits grew, eroding the epithelium covering the renal papillae, coming into contact with urine and starting the development of COM calculi. Subepithelial HAP plaques may alter the epithelium covering the papillae, resulting in the deposit of COM crystals directly onto the epithelium. Tissue calcification depends on a pre-existing injury, the continuation of this process is due to modulators and/or crystallization inhibitors deficiency. Conclusions Since calculus morphology and the amount of detected HAP are dependent on the location and widespread of calcified injury, all types of papillary COM calculi can be found in the same patient. All patients had subepithelial calcifications, with fewer papillary calculi, demonstrating that some subepithelial calcifications did not further evolve and were reabsorbed. A high number of subepithelial calcifications increases the likelihood that some will be transformed into COM papillary calculi. PMID:23497010

  19. FT-IR spectral studies on certain human urinary stones in the patients of rural area

    NASA Astrophysics Data System (ADS)

    Selvaraju, R.; Thiruppathi, G.; Raja, A.

    Fourier transform infrared spectroscopy (FT-IR) has been carried out to analyze the organic and inorganic constituent of human urinary stones. Patient's hailing from Rajah Muthiah Medical College and Hospital, Annamalai University, Tamil Nadu, India was selected for the study. The FT-IR results indicate that stones have different composition, i.e., namely calcium oxalate, calcium phosphate, carbonate apatite and magnesium ammonium phosphate and uric acid. From the spectral and powder X-ray diffraction pattern, the chemical constituents of urinary stones were identified. The quantitative estimations of calcium oxalate monohydrate (COM) 1620 cm-1, calcium phosphate (apatite) 1037 cm-1, magnesium ammonium phosphate (struvite) 1010 cm-1, calcium carbonate 1460 cm-1 and uric acid 1441 cm-1 were calculated using particular peaks of FT-IR studies. The study reveals that calcium oxalate monohydrate and calcium phosphate type urinary stones were predominant whereas magnesium ammonium phosphate are in moderate level, and calcium carbonate and uric acid are in low. Calcium phosphate is found in all the stones and calcium oxalate monohydrate is found to be higher. Quantitative analyses of urinary stones show that calcium oxalate monohydrate (40%), apatite (30%), magnesium ammonium phosphate (23%) and uric acid (7%) are present in all the urinary stone samples.

  20. FT-IR spectral studies on certain human urinary stones in the patients of rural area.

    PubMed

    Selvaraju, R; Thiruppathi, G; Raja, A

    2012-07-01

    Fourier transform infrared spectroscopy (FT-IR) has been carried out to analyze the organic and inorganic constituent of human urinary stones. Patient's hailing from Rajah Muthiah Medical College and Hospital, Annamalai University, Tamil Nadu, India was selected for the study. The FT-IR results indicate that stones have different composition, i.e., namely calcium oxalate, calcium phosphate, carbonate apatite and magnesium ammonium phosphate and uric acid. From the spectral and powder X-ray diffraction pattern, the chemical constituents of urinary stones were identified. The quantitative estimations of calcium oxalate monohydrate (COM) 1,620 cm(-1), calcium phosphate (apatite) 1,037 cm(-1), magnesium ammonium phosphate (struvite) 1,010 cm(-1), calcium carbonate 1,460 cm(-1) and uric acid 1,441 cm(-1) were calculated using particular peaks of FT-IR studies. The study reveals that calcium oxalate monohydrate and calcium phosphate type urinary stones were predominant whereas magnesium ammonium phosphate are in moderate level, and calcium carbonate and uric acid are in low. Calcium phosphate is found in all the stones and calcium oxalate monohydrate is found to be higher. Quantitative analyses of urinary stones show that calcium oxalate monohydrate (40%), apatite (30%), magnesium ammonium phosphate (23%) and uric acid (7%) are present in all the urinary stone samples. PMID:22484261

  1. The Interaction between Enterobacteriaceae and Calcium Oxalate Deposits

    PubMed Central

    Barr-Beare, Evan; Saxena, Vijay; Hilt, Evann E.; Thomas-White, Krystal; Schober, Megan; Li, Birong; Becknell, Brian; Hains, David S.; Wolfe, Alan J.; Schwaderer, Andrew L.

    2015-01-01

    Background The role of calcium oxalate crystals and deposits in UTI pathogenesis has not been established. The objectives of this study were to identify bacteria present in pediatric urolithiasis and, using in vitro and in vivo models, to determine the relevance of calcium oxalate deposits during experimental pyelonephritis. Methods Pediatric kidney stones and urine were collected and both cultured and sequenced for bacteria. Bacterial adhesion to calcium oxalate was compared. Murine kidney calcium oxalate deposits were induced by intraperitoneal glyoxalate injection and kidneys were transurethrally inoculated with uropathogenic Escherichia coli to induce pyelonephritis Results E. coli of the family Enterobacteriaceae was identified in patients by calcium oxalate stone culture. Additionally Enterobacteriaceae DNA was sequenced from multiple calcium oxalate kidney stones. E. coli selectively aggregated on and around calcium oxalate monohydrate crystals. Mice inoculated with glyoxalate and uropathogenic E. coli had higher bacterial burdens, increased kidney calcium oxalate deposits and an increased kidney innate immune response compared to mice with only calcium oxalate deposits or only pyelonephritis. Conclusions In a murine model, the presence of calcium oxalate deposits increases pyelonephritis risk, likely due to preferential aggregation of bacteria on and around calcium oxalate crystals. When both calcium oxalate deposits and uropathogenic bacteria were present, calcium oxalate deposit number increased along with renal gene transcription of inner stone core matrix proteins increased. Therefore renal calcium oxalate deposits may be a modifiable risk factor for infections of the kidney and urinary tract. Furthermore, bacteria may be present in calcium oxalate deposits and potentially contribute to calcium oxalate renal disease. PMID:26448465

  2. Does the Use of Chitosan Contribute to Oxalate Kidney Stone Formation?

    PubMed Central

    Queiroz, Moacir Fernandes; Teodosio Melo, Karoline Rachel; Sabry, Diego Araujo; Sassaki, Guilherme Lanzi; Rocha, Hugo Alexandre Oliveira

    2014-01-01

    Chitosan is widely used in the biomedical field due its chemical and pharmacological properties. However, intake of chitosan results in renal tissue accumulation of chitosan and promotes an increase in calcium excretion. On the other hand, the effect of chitosan on the formation of calcium oxalate crystals (CaOx) has not been described. In this work, we evaluated the antioxidant capacity of chitosan and its interference in the formation of CaOx crystals in vitro. Here, the chitosan obtained commercially had its identity confirmed by nuclear magnetic resonance and infrared spectroscopy. In several tests, this chitosan showed low or no antioxidant activity. However, it also showed excellent copper-chelating activity. In vitro, chitosan acted as an inducer mainly of monohydrate CaOx crystal formation, which is more prevalent in patients with urolithiasis. We also observed that chitosan modifies the morphology and size of these crystals, as well as changes the surface charge of the crystals, making them even more positive, which can facilitate the interaction of these crystals with renal cells. Chitosan greatly influences the formation of crystals in vitro, and in vivo analyses should be conducted to assess the risk of using chitosan. PMID:25551781

  3. Does the use of chitosan contribute to oxalate kidney stone formation?

    PubMed

    Fernandes Queiroz, Moacir; Melo, Karoline Rachel Teodosio; Sabry, Diego Araujo; Sassaki, Guilherme Lanzi; Rocha, Hugo Alexandre Oliveira

    2015-01-01

    Chitosan is widely used in the biomedical field due its chemical and pharmacological properties. However, intake of chitosan results in renal tissue accumulation of chitosan and promotes an increase in calcium excretion. On the other hand, the effect of chitosan on the formation of calcium oxalate crystals (CaOx) has not been described. In this work, we evaluated the antioxidant capacity of chitosan and its interference in the formation of CaOx crystals in vitro. Here, the chitosan obtained commercially had its identity confirmed by nuclear magnetic resonance and infrared spectroscopy. In several tests, this chitosan showed low or no antioxidant activity. However, it also showed excellent copper-chelating activity. In vitro, chitosan acted as an inducer mainly of monohydrate CaOx crystal formation, which is more prevalent in patients with urolithiasis. We also observed that chitosan modifies the morphology and size of these crystals, as well as changes the surface charge of the crystals, making them even more positive, which can facilitate the interaction of these crystals with renal cells. Chitosan greatly influences the formation of crystals in vitro, and in vivo analyses should be conducted to assess the risk of using chitosan. PMID:25551781

  4. [The quantitative study of inhibitory effect of pentosan polysulfate and chlorophyllin on the experimental calcium oxalate stone].

    PubMed

    Miyazawa, K; Suzuki, K; Tsugawa, R

    1989-06-01

    The purpose of this study is to evaluate the effect of sodium pentosan polysulfate (SPP) and sodium copper chlorophyllin (SCC) on the formation, growth and aggregation of calcium oxalate crystals in vivo, and to measure the number and the volume of crystals formed in the rat kidney, quantitatively, with a Coulter counter TA-II. The deposition of calcium oxalate crystals in the rat kidney was induced by intraperitoneal injection of 2.5 g per Kg of body weight of hydroxy-L-proline and administration of 0.4% ethylene glycol as the drinking fluid ad libitum for 7 days. Daily excretions of urinary oxalate, calcium (ratio to urinary creatinine) and urinary volume were measured. Both kidneys were removed after protocol. The kidneys were homogenized with 0.2 M Tris-buffer (pH 8.0) and subsequently digested in soluene-100. After calcium oxalate crystals were collected, they were suspended in saline saturated with calcium oxalate. The crystal size distribution was measured with a Coulter counter TA-II. In addition, the renal calcium content was measured by atomic absorption spectrometry, and the kidneys were examined by optical microscopy and scanning electron microscopy. The crystals formed in the rats' kidneys were analyzed by infrared spectroscopy. The results were as follows: 1. There was no deposition of crystals in the kidney of the rats which were not treated. There was intratubular deposition of crystals in the kidneys of the rats injected with hydroxy-L-proline and administered 0.4% ethylene glycol. They consisted of calcium oxalate monohydrate. 2. Renal calcium content was significantly higher in the groups with induced crystals than the control group.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2477580

  5. Micro-mechanical model of calcium oxalate monohydrate aggregation in supersaturated solutions: Effect of crystal form and seed concentration

    NASA Astrophysics Data System (ADS)

    Pitt, K.; Mitchell, G. P.; Ray, A.; Heywood, B. R.; Hounslow, M. J.

    2012-12-01

    In this paper we report crystal growth and aggregation behaviour for calcium oxalate monohydrate (COM) in a stirred tank for two differing seed types - rounded and well defined - at various seed loadings. Initially we used our previously developed model [1] to study the growth and aggregation. In this model a dimensionless strength, termed the Mumtaz number, has been formulated, which accounts for the effects of stirring, supersaturation and particle size on the aggregation rate of COM. Subtle differences in growth and aggregation rates were observed between the two populations of crystals; the model was unable to describe this behaviour. These differences were attributed to their different surface characteristics. Growth and aggregation kinetic parameters were also seen to be highly dependent on seed loading. This is attributed to poisoning by an unknown trace impurity, the effect of which is dependent on seed loading. This has led to the development of a new model to account for both surface characteristics and the presence of a trace impurity that adsorbs onto the surface of crystals pinning growth steps. At low seeds loadings, surface coverage by the impurity is higher and so growth rates are reduced. These results are very well described by an extension of the approach of Weaver et al. [2]. We use Liew et al.'s [1] model to represent aggregation by a collision efficiency that depends on a modified Mumtaz number. This model requires the determination of a simple group of parameters that we term the 'aggregation tendency'. The relationship between aggregation tendency and growth rate constant suggests that aggregation is in fact controlled by the growth rate of some high-energy facets not expressed macroscopically. The fact that aggregation tendency increases with surface coverage of impurity further suggests that the presence of impurity gives rise to longer or more numerous linear features along which initial contact between crystals takes place. The combined growth and aggregation models are capable of describing all the experiments reported here for both seed types and over a range of seed loadings.

  6. Peeping into Human Renal Calcium Oxalate Stone Matrix: Characterization of Novel Proteins Involved in the Intricate Mechanism of Urolithiasis

    PubMed Central

    Tandon, Chanderdeep

    2013-01-01

    Background The increasing number of patients suffering from urolithiasis represents one of the major challenges which nephrologists face worldwide today. For enhancing therapeutic outcomes of this disease, the pathogenic basis for the formation of renal stones is the need of hour. Proteins are found as major component in human renal stone matrix and are considered to have a potential role in crystal–membrane interaction, crystal growth and stone formation but their role in urolithiasis still remains obscure. Methods Proteins were isolated from the matrix of human CaOx containing kidney stones. Proteins having MW>3 kDa were subjected to anion exchange chromatography followed by molecular-sieve chromatography. The effect of these purified proteins was tested against CaOx nucleation and growth and on oxalate injured Madin–Darby Canine Kidney (MDCK) renal epithelial cells for their activity. Proteins were identified by Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF MS) followed by database search with MASCOT server. In silico molecular interaction studies with CaOx crystals were also investigated. Results Five proteins were identified from the matrix of calcium oxalate kidney stones by MALDI-TOF MS followed by database search with MASCOT server with the competence to control the stone formation process. Out of which two proteins were promoters, two were inhibitors and one protein had a dual activity of both inhibition and promotion towards CaOx nucleation and growth. Further molecular modelling calculations revealed the mode of interaction of these proteins with CaOx at the molecular level. Conclusions We identified and characterized Ethanolamine-phosphate cytidylyltransferase, Ras GTPase-activating-like protein, UDP-glucose:glycoprotein glucosyltransferase 2, RIMS-binding protein 3A, Macrophage-capping protein as novel proteins from the matrix of human calcium oxalate stone which play a critical role in kidney stone formation. Thus, these proteins having potential to modulate calcium oxalate crystallization will throw light on understanding and controlling urolithiasis in humans. PMID:23894559

  7. Analysis of urinary stone composition in Eastern India by X-ray diffraction crystallography

    PubMed Central

    Jindal, Tarun; Mandal, Soumendra Nath; Sonar, Pankaj; Kamal, Mir Reza; Ghosh, Nabankur; Karmakar, Dilip

    2014-01-01

    Background: Stones in the urinary system are common in our country. This study was done to assess the composition of the urinary stones in eastern part of India. Materials and Methods: A prospective study was done over a period of thirty months. A total of 90 stones were analyzed in this time period by using X-ray diffraction crystallography. Results: Of the 90 stones analyzed, 77 were renal stones, 12 were ureteric stones and one was a bladder stone. Six stones (all renal) did not have properties to be represented by X-ray diffraction crystallography. The overall prevalence of the oxalate containing stones was 85.7% with calcium oxalate monohydrate (COM) being the major constituent. Calcium oxalate dihydrate (COD) was the next most common constituent. Struvite stones constituted 9.5% of the stones analyzed. Pure calcium phosphate stones were found in 4.7% of the cases. Conclusion: Our study reveals that the stone composition in the eastern part of India is different from that in other parts of the country. We have a comparatively lower prevalence of oxalate stones while a higher prevalence of phosphate and struvite stones. PMID:25337533

  8. Kidney Stones in Primary Hyperoxaluria: New Lessons Learnt

    PubMed Central

    Jacob, Dorrit E.; Grohe, Bernd; Gener, Michaela; Beck, Bodo B.; Hoppe, Bernd

    2013-01-01

    To investigate potential differences in stone composition with regard to the type of Primary Hyperoxaluria (PH), and in relation to the patients medical therapy (treatment nave patients versus those on preventive medication) we examined twelve kidney stones from ten PH I and six stones from four PH III patients. Unfortunately, no PH II stones were available for analysis. The study on this set of stones indicates a more diverse composition of PH stones than previously reported and a potential dynamic response of morphology and composition of calculi to treatment with crystallization inhibitors (citrate, magnesium) in PH I. Stones formed by PH I patients under treatment are more compact and consist predominantly of calcium-oxalate monohydrate (COM, whewellite), while calcium-oxalate dihydrate (COD, weddellite) is only rarely present. In contrast, the single stone available from a treatment nave PH I patient as well as stones from PH III patients prior to and under treatment with alkali citrate contained a wide size range of aggregated COD crystals. No significant effects of the treatment were noted in PH III stones. In disagreement with findings from previous studies, stones from patients with primary hyperoxaluria did not exclusively consist of COM. Progressive replacement of COD by small COM crystals could be caused by prolonged stone growth and residence times in the urinary tract, eventually resulting in complete replacement of calcium-oxalate dihydrate by the monohydrate form. The noted difference to the nave PH I stone may reflect a reduced growth rate in response to treatment. This pilot study highlights the importance of detailed stone diagnostics and could be of therapeutic relevance in calcium-oxalates urolithiasis, provided that the effects of treatment can be reproduced in subsequent larger studies. PMID:23940605

  9. Experimental determination of multiple thermodynamic and kinetic risk factors for nephrolithiasis in the urine of healthy controls and calcium oxalate stone formers: does a universal discriminator exist?

    PubMed

    Rodgers, A L; Webber, D; Hibberd, B

    2015-11-01

    Nephrolithiasis is thought to be governed by urinary thermodynamic and kinetic risk factors. However, identification of one or more of these factors which consistently and unambiguously differentiates between healthy subjects (N) and calcium oxalate (CaOx) renal stone patients (SF) remains elusive. The present study addresses this challenge. 24 h urines were collected from 15 N and 10 SF. Urine compositions were used to compute thermodynamic risk indices including urinary ratios, quotients and supersaturation (SS) values, while CaOx metastable limits (MSL) were determined experimentally. Crystallisation kinetics was determined by measuring rates of particle formation (number, volume, size) using a Coulter counter multisizer (CC) and a Coulter flow cytometer (FC). Particle shapes were qualitatively differentiated by FC and were viewed directly by scanning electron microscopy. Several urinary composition ratios and risk quotients were significantly different between the groups. However, there were no significant differences between CaOx MSL or SS values. Using transformed FC data, the rate of CaOx crystallisation in SF was significantly greater than in N. This was not supported by CC measurements. There were no significant differences between the groups with respect to particle size or CaOx crystal growth rates. Single and aggregated CaOx dihydrate crystals were observed in both groups with equal frequency and there were no differences in the kinetic properties of these deposits. A few CaOx monohydrate crystals were observed in SF. Although several risk factors were found to be significantly different between the groups, none of them were consistently robust when compared to other cognate factors. Arguments were readily invoked which demonstrated inter-factor inconsistencies and conflicts. We suspect that a unique discriminatory factor, such as any of those which we investigated in the present study, may not exist. PMID:26198547

  10. Androgen receptor enhances kidney stone-CaOx crystal formation via modulation of oxalate biosynthesis & oxidative stress.

    PubMed

    Liang, Liang; Li, Lei; Tian, Jing; Lee, Soo Ok; Dang, Qiang; Huang, Chiung-Kuei; Yeh, Shuyuan; Erturk, Erdal; Bushinsky, David; Chang, Luke S; He, Dalin; Chang, Chawnshang

    2014-08-01

    Males develop kidney stones far more frequently than females with a ratio of 2-3:1, suggesting that androgen receptor (AR) signaling might play a key role in the development of nephrolithiasis. Using the cre-loxP system to selectively knock out AR in glyoxylate-induced calcium oxalate (CaOx) crystal mouse models, we found that the mice lacking hepatic AR had less oxalate biosynthesis, which might lead to lower CaOx crystal formation, and that the mice lacking kidney proximal or distal epithelial AR also had lower CaOx crystal formation. We found that AR could directly up-regulate hepatic glycolate oxidase and kidney epithelial NADPH oxidase subunit p22-PHOX at the transcriptional level. This up-regulation might then increase oxalate biosynthesis and oxidative stress that resulted in induction of kidney tubular injury. Targeting AR with the AR degradation enhancer ASC-J9 led to suppression of CaOx crystal formation via modulation of oxalate biosynthesis and oxidative stress in both in vitro and in vivo studies. Taken together, these results established the roles of AR in CaOx crystal formation. PMID:24956378

  11. Androgen Receptor Enhances Kidney Stone-CaOx Crystal Formation via Modulation of Oxalate Biosynthesis & Oxidative Stress

    PubMed Central

    Liang, Liang; Li, Lei; Tian, Jing; Lee, Soo Ok; Dang, Qiang; Huang, Chiung-Kuei; Yeh, Shuyuan; Erturk, Erdal; Bushinsky, David; Chang, Luke S.

    2014-01-01

    Males develop kidney stones far more frequently than females with a ratio of 2–3:1, suggesting that androgen receptor (AR) signaling might play a key role in the development of nephrolithiasis. Using the cre-loxP system to selectively knock out AR in glyoxylate-induced calcium oxalate (CaOx) crystal mouse models, we found that the mice lacking hepatic AR had less oxalate biosynthesis, which might lead to lower CaOx crystal formation, and that the mice lacking kidney proximal or distal epithelial AR also had lower CaOx crystal formation. We found that AR could directly up-regulate hepatic glycolate oxidase and kidney epithelial NADPH oxidase subunit p22-PHOX at the transcriptional level. This up-regulation might then increase oxalate biosynthesis and oxidative stress that resulted in induction of kidney tubular injury. Targeting AR with the AR degradation enhancer ASC-J9 led to suppression of CaOx crystal formation via modulation of oxalate biosynthesis and oxidative stress in both in vitro and in vivo studies. Taken together, these results established the roles of AR in CaOx crystal formation. PMID:24956378

  12. Turning sunlight into stone: the oxalate-carbonate pathway in a tropical tree ecosystem

    NASA Astrophysics Data System (ADS)

    Cailleau, G.; Braissant, O.; Verrecchia, E. P.

    2011-02-01

    An African oxalogenic tree, the iroko tree (Milicia excelsa), has the property to enhance carbonate precipitation in tropical oxisols, where such accumulations are not expected due to the theoretical acidic conditions of these soils. This uncommon process is linked to the oxalate-carbonate pathway, which increases soil pH through oxalate oxidation. In order to investigate the oxalate-carbonate pathway in the iroko system, fluxes of matter have been identified, described, and evaluated from field to microscopic scales. In the first centimeters of the soil profile, decaying of the organic matter allows the release of whewellite crystals, mainly due to the action of termites and saprophytic fungi. Regarding the carbonate flux, another direct consequence of wood feeding is a concomitant flux of carbonate formed in wood tissues, which is not consumed by termites. Nevertheless, calcite biomineralization of the tree is not a consequence of in situ oxalate consumption, but rather related to the oxalate oxidation inside the upper part of the soil. The consequence of this oxidation is the presence of carbonate ions in the soil solution pumped through the roots, leading to preferential mineralization of the roots and the trunk base. An ideal scenario for the iroko biomineralization and soil carbonate accumulation starts with oxalatization: as the iroko tree grows, the organic matter flux to the soil constitutes the litter. Therefore, an oxalate pool is formed on the forest ground. Then, wood rotting gents (mainly termites, fungi, and bacteria) release significant amounts of oxalate crystals from decaying plant tissues. In addition some of these gents are themselves producers of oxalate (fungi). Both processes contribute to a soil pool of "available" oxalate crystals. Oxalate consumption by oxalotrophic bacteria can start. Carbonate and calcium ions present in the soil solution represent the end products of the oxalate-carbonate pathway. The solution is pumped through the roots, leading to carbonate precipitation. The main pools of carbon are clearly identified as the organic matter (the tree and its organic products), the oxalate crystals, and the various carbonate features. A functional model based on field observations and diagenetic investigations with δ13C signatures of the various compartments involved in the local carbon cycle is proposed. It suggests that the iroko ecosystem can act as a long-term carbon sink, as long as the calcium source is related to non-carbonate rocks. Consequently, this carbon sink, driven by the oxalate carbonate pathway around an iroko tree, constitutes a true carbon trapping ecosystem as define by the ecological theory.

  13. Turning sunlight into stone: the oxalate-carbonate pathway in a tropical tree ecosystem

    NASA Astrophysics Data System (ADS)

    Cailleau, G.; Braissant, O.; Verrecchia, E. P.

    2011-07-01

    An African oxalogenic tree, the iroko tree (Milicia excelsa), has the property to enhance carbonate precipitation in tropical oxisols, where such accumulations are not expected due to the acidic conditions in these types of soils. This uncommon process is linked to the oxalate-carbonate pathway, which increases soil pH through oxalate oxidation. In order to investigate the oxalate-carbonate pathway in the iroko system, fluxes of matter have been identified, described, and evaluated from field to microscopic scales. In the first centimeters of the soil profile, decaying of the organic matter allows the release of whewellite crystals, mainly due to the action of termites and saprophytic fungi. In addition, a concomitant flux of carbonate formed in wood tissues contributes to the carbonate flux and is identified as a direct consequence of wood feeding by termites. Nevertheless, calcite biomineralization of the tree is not a consequence of in situ oxalate consumption, but rather related to the oxalate oxidation inside the upper part of the soil. The consequence of this oxidation is the presence of carbonate ions in the soil solution pumped through the roots, leading to preferential mineralization of the roots and the trunk base. An ideal scenario for the iroko biomineralization and soil carbonate accumulation starts with oxalatization: as the iroko tree grows, the organic matter flux to the soil constitutes the litter, and an oxalate pool is formed on the forest ground. Then, wood rotting agents (mainly termites, saprophytic fungi, and bacteria) release significant amounts of oxalate crystals from decaying plant tissues. In addition, some of these agents are themselves producers of oxalate (e.g. fungi). Both processes contribute to a soil pool of "available" oxalate crystals. Oxalate consumption by oxalotrophic bacteria can then start. Carbonate and calcium ions present in the soil solution represent the end products of the oxalate-carbonate pathway. The solution is pumped through the roots, leading to carbonate precipitation. The main pools of carbon are clearly identified as the organic matter (the tree and its organic products), the oxalate crystals, and the various carbonate features. A functional model based on field observations and diagenetic investigations with δ13C signatures of the various compartments involved in the local carbon cycle is proposed. It suggests that the iroko ecosystem can act as a long-term carbon sink, as long as the calcium source is related to non-carbonate rocks. Consequently, this carbon sink, driven by the oxalate carbonate pathway around an iroko tree, constitutes a true carbon trapping ecosystem as defined by ecological theory.

  14. FT-Raman spectral analysis of human urinary stones.

    PubMed

    Selvaraju, R; Raja, A; Thiruppathi, G

    2012-12-01

    FT-Raman spectroscopy is the most useful tool for the purpose of bio-medical diagnostics. In the present study, FT-Raman spectral method is used to investigate the chemical composition of urinary calculi. Urinary calculi multi-components such as calcium oxalate, hydroxyl apatite, struvite and uric acid are studied. FT-Raman spectrum has been recorded in the range of 3500-400 cm(-1). Chemical compounds are identified by Raman spectroscopic technique. The quantitative estimations of calcium oxalate monohydrate (COM) 1463 cm(-1), calcium oxalate dehydrate (COD) 1478 cm(-1), hydroxyl apatite 959 cm(-1), struvite 575 cm(-1), uric acid 1283 cm(-1) and oxammite (ammonium oxalate monohydrate) 2129 cm(-1) are calculated using particular peaks of FT-Raman spectrum. The quantitative estimation of human urinary stones suitable for the single calibration curve was performed. PMID:23069621

  15. The use of non-contrast computed tomography and color Doppler ultrasound in the characterization of urinary stones - preliminary results

    PubMed Central

    Bulakçı, Mesut; Tefik, Tzevat; Akbulut, Fatih; Örmeci, Mehmet Tolgahan; Beşe, Caner; Şanlı, Öner; Oktar, Tayfun; Salmaslıoğlu, Artür

    2015-01-01

    Objective To investigate the role of density value in computed tomography (CT) and twinkling artifact observed in color Doppler analysis for the prediction of the mineral composition of urinary stones. Material and methods A total of 42 patients who were operated via percutaneous or endoscopic means and had undergone abdominal non-contrast CT and color Doppler ultrasonography examinations were included in the study. X-ray diffraction method was utilized to analyze a total of 86 stones, and the correlations between calculated density values and twinkling intensities with stone types were investigated for each stone. Results Analyses of extracted stones revealed the presence of 40 calcium oxalate monohydrate, 12 calcium oxalate dihydrate, 9 uric acid, 11 calcium phosphate, and 14 cystine stones. The density values were calculated as 1499±269 Hounsfield Units (HU) for calcium oxalate monohydrate, 1505±221 HU for calcium oxalate dihydrate, 348±67 HU for uric acid, 1106±219 HU for calcium phosphate, and 563±115 HU for cystine stones. The artifact intensities were determined as grade 0 in 15, grade 1 in 32, grade 2 in 24, and grade 3 in 15 stones. Conclusion In case the density value of the stone is measured below 780 HU and grade 3 artifact intensity is determined, it can be inferred that the mineral composition of the stone tends to be cystine. PMID:26623143

  16. How the overlapping timescales for peptide binding and terrace exposure lead to non-linear step dynamics during growth of calcium oxalate monohydrate

    PubMed Central

    Weaver, M.L.; Qiu, S.R.; Friddle, R.W.; Casey, W.H.; De Yoreo, J.J.

    2010-01-01

    Using in situ atomic force microscopy (AFM), we investigate the inhibition of calcium oxalate monohydrate (COM) step growth by aspartic acid-rich peptides and find that the magnitude of the effect depends on terrace lifetime. We then derive a time dependent step-pinning model in which average impurity spacing depends on the terrace lifetime as given by the ratio of step spacing to step speed. We show that the measured variation in step speed is well fit by the model and allows us to extract the characteristic peptide adsorption time. The model also predicts that a crossover in the timescales for impurity adsorption and terrace exposure leads to bistable growth dynamics described mathematically by a catastrophe. We observe this behavior experimentally both through the sudden drop in step speed to zero upon decrease of supersaturation as well as through fluctuations in step speed between the two limiting values at the point where the catastrophe occurs. We discuss the models general applicability to macromolecular modifiers and biomineral phases. PMID:20835404

  17. Surface aggregation of urinary proteins and aspartic acid-rich peptides on the faces of calcium oxalate monohydrate investigated by in situ force microscopy

    SciTech Connect

    Weaver, M L; Qiu, S R; Hoyer, J R; Casey, W H; Nancollas, G H; De Yoreo, J J

    2008-05-28

    The growth of calcium oxalate monohydrate in the presence of Tamm-Horsfall protein (THP), osteopontin (OPN), and the 27-residue synthetic peptides (DDDS){sub 6}DDD and (DDDG){sub 6}DDD [where D = aspartic acid and X = S (serine) or G (glycine)] was investigated via in situ atomic force microscopy (AFM). The results show that these three growth modulators create extensive deposits on the crystal faces. Depending on the modulator and crystal face, these deposits can occur as discrete aggregates, filamentary structures, or uniform coatings. These proteinaceous films can lead to either the inhibition or increase of the step speeds (with respect to the impurity-free system) depending on a range of factors that include peptide or protein concentration, supersaturation and ionic strength. While THP and the linear peptides act, respectively, to exclusively increase and inhibit growth on the (-101) face, both exhibit dual functionality on the (010) face, inhibiting growth at low supersaturation or high modulator concentration and accelerating growth at high supersaturation or low modulator concentration. Based on analyses of growth morphologies and dependencies of step speeds on supersaturation and protein or peptide concentration, we argue for a picture of growth modulation that accounts for the observations in terms of the strength of binding to the surfaces and steps and the interplay of electrostatic and solvent-induced forces at crystal surface.

  18. Structural characterization and vibrational studies of human urinary stones from Istanbul, Turkey.

    PubMed

    Kocademir, Mustafa; Baykal, Abdulhadi; Kumru, Mustafa; Tahmaz, M Lutfu

    2016-05-01

    Seven human urinary stones were collected from urinary bladders of patients hailing from Istanbul, Turkey. Their XRD, EDX, FT-IR and FT-Raman spectra as well as SEM images have been recorded to determine their chemical compositions, morphologies, crystal structures, and crystallite sizes. XRD and vibrational (FT-IR and FT-Raman) analyses indicate that six out of the seven stones have identical contents. The ratios of organic and inorganic contents of the stones have been determined by their thermogravimetric analyses. The stones have been found to contain calcium oxalate monohydrate and apatite as the major components. PMID:26890204

  19. Bulk crystal growth, optical, mechanical and ferroelectric properties of new semiorganic nonlinear optical and piezoelectric Lithium nitrate monohydrate oxalate single crystal

    NASA Astrophysics Data System (ADS)

    Dalal, Jyoti; Kumar, Binay

    2016-01-01

    New semiorganic nonlinear optical single crystals of Lithium nitrate oxalate monohydrate (LNO) were grown by slow evaporation solution technique. Single crystal X-ray diffraction study indicated that LNO crystal belongs to the triclinic system with space group P1. Various functional groups present in the material were identified by FTIR and Raman analysis. UV-vis study showed the high transparency of crystals with a wide band gap 5.01 eV. Various Optical constants i.e. Urbach energy (Eu), extinction coefficient (K), refractive index, optical conductivity, electric susceptibility with real and imaginary parts of dielectric constant were calculated using the transmittance data which have applications in optoelectronic devices. A sharp emission peak was found at 438 nm in photoluminescence measurement, which revealed suitability of crystal for fabricating violet lasers. In dielectric studies, a peak has been observed at 33 C which is due to ferroelectric to paraelectric phase transition. Piezoelectric charge coefficients (d33 = 9.2 pC/N and g33) have been calculated, which make it a suitable for piezoelectric devices applications. In ferroelectric studies, a saturated loop was found in which the values of coercive field and remnant polarization were found to be 2.18 kV/cm and 0.39 ?C/cm2, respectively. Thermal behavior was studied by TGA and DSC studies. The relative SHG efficiency of LNO was found to be 1.2 times that of KDP crystal. In microhardness study, Meyer's index value was found to be 1.78 which revealed its soft nature. These optical, dielectric, piezoelectric, ferroelectric, mechanical and non-linear optical properties of grown crystal establish the usefulness of this material for optoelectronics, non-volatile memory and piezoelectric devices applications.

  20. [Renal oxalate excretion following oral oxalate load in patients with urinary calculus disease and healthy controls].

    PubMed

    Ebisuno, S; Morimoto, S; Yoshida, T; Fukatani, T; Yasukawa, S; Okawa, T

    1986-12-01

    Oral oxalate loading using sodium oxalate or a vegetable juice was done to evaluate the intestinal absorption of exogenous oxalate in 30 patients with renal stones and 13 healthy controls. Fifteen calcium oxalate stone formers, 7 non-oxalate stone formers and 10 healthy volunteers were given an oral loading of sodium oxalate (500 mg). Urinary oxalate increased promptly, reaching a peak value within 4 to 8 hours after administration of a synthetic oxalate orally in a fasting state. In calcium oxalate stone formers, the mean increment of urinary oxalate and the bioavailability following oral sodium oxalate load were significantly higher than in the healthy controls and non-oxalate stone formers. Furthermore, intestinal hyperabsorption of oxalate in our criterion was defined in six patients with calcium oxalate stones (40%). On the other hand, eight calcium oxalate stone formers and three healthy controls were given vegetable juice. Urinary oxalate was increased only slightly after the ingestion, and there was no difference between calcium oxalate stone formers and normal controls. These results suggest that a certain hyperoxaluria might be induced by intestinal absorption of exogenous oxalate, and that the hyperabsorption might indicate a possible risk factor for calcium oxalate stone formation. PMID:3825824

  1. Solvent effect in vitro of Anticolana Valley water on renal stones: analytical-instrumental study.

    PubMed

    De Angelis Curtis, S; Curini, R; Fraioli, A; Petronio, B M; Ricciuti, G; D'Ascenzo, G

    1999-01-01

    The presence of humic and fulvic acids in the Anticolana Valley (Fiuggi) water has been established. On the basis of this evidence we investigated the capacity of Anticolana Valley (Fiuggi) water to dissolve renal calculi in vitro. Crystals of calcium oxalate monohydrate to simulate a kidney stone were prepared. Human renal stones of calcium oxalate monohydrate were obtained by courtesy of the Division of Urology of 'La Sapienza' University (Rome), the Division of Urology of the University of Havana (Cuba) and the ASTIF of Fiuggi. The study was performed using the Anticolana Valley (Fiuggi) water, distilled water and tap water (ACEA, Rome), in a specially designed Perspex apparatus. Each calculus was subjected to a water flow of 2 liters/24 h. The capacity of the Anticolana Valley (Fiuggi) water to dissolve human and synthetic calculi was found to be much higher than that of distilled water which in turn was significantly more effective than tap (ACEA) water. PMID:9873221

  2. Separate effects of urinary chondroitin sulphate and heparan sulphate on the crystallization of urinary calcium oxalate: differences between stone formers and normal control subjects.

    PubMed

    Shum, D K; Gohel, M D

    1993-07-01

    1. Urinary glycosaminoglycans were recovered from the papain digest of polyanions precipitated sequentially by cetylpyridinium chloride and sodium acetate-saturated ethanol. Those from the early morning urine of 48 stone formers and 43 normal control subjects measured 11 and 16 micrograms of uronic acid/ml of urine, respectively. 2. Preparative agarose gel electrophoresis of the recovered glycosaminoglycans in barium acetate buffer (pH 5.8) yielded fractions containing purely chondroitin sulphate, co-polymeric chondroitin/dermatan sulphates and heparan sulphate. Identification was based on the susceptibility of the fractions to chondroitinase or nitrous acid treatment. Similar compositions of glycosaminoglycan classes were observed in samples from stone formers and normal control subjects. 3. The fractionated glycosaminoglycans were dissolved in urine ultrafiltrate to assay for nucleation-promoting and growth-inhibiting activities towards crystallization of urinary calcium oxalate. When compared at the same uronic acid concentration, both the urinary chondroitin sulphate isomers and heparan sulphates of stone formers demonstrated the capacity to enhance crystal nucleation from calcium oxalate endogenous in urine ultrafiltrates, whereas only urinary heparan sulphates of normal control subjects demonstrated this capacity. 4. Tissue-derived reference chondroitin sulphate, dermatan sulphate and heparin, when similarly tested, showed negligible crystal nucleation-promoting activity. The tissue-derived heparan sulphate was similar to the urinary heparan sulphates in showing marked crystal nucleation-promoting activity. 5. Crystal-growth inhibitory activity was evident in all urinary glycosaminoglycan fractions studied. In particular, urinary heparan sulphate of normal control subjects showed higher activity than that of stone formers or the chondroitin sulphate isomers of both stone formers and normal control subjects (P < 0.005). PMID:8149691

  3. Stimulation of synovial fibroblasts by calcium oxalate and monosodium urate monohydrate. A mechanism of connective tissue degradation in oxalosis and gout.

    PubMed

    Hasselbacher, P

    1982-12-01

    The responses of cultured rabbit synovial fibroblasts to amorphous and microcrystalline calcium oxalate were compared with responses to MSUM. Like urate crystals, crystalline calcium oxalate (but not amorphous oxalate) caused marked stimulation of secretion of latent collagenase and PGE2 after 3 days of culture without significant change in cell protein or gross cellular morphology. Collagenase rose from undetectable levels in control cultures to 32.4 +/- 6.0 and 27.4 +/- 7.9 U/mg of cell protein for crystalline calcium oxalate and MSUM, respectively. PGE2 rose from a control level of 0.24 +/- 0.14 to 19.47 +/- 5.15 and 23 +/- 4.84 micrograms/mg of cell protein for crystalline calcium oxalate and sodium urate compared to 1.22 +/- 0.48 microgram for amorphous calcium oxalate. Although the crystalline species studied caused LDH in the media to increase threefold, this was minimal. Cell stimulation by amorphous oxalate and the crystals did not correlate with membranolytic potential as measured with an erythrocyte lysis assay. Stimulation of resident synovial cells by crystalline calcium oxalate and sodium urate may contribute to the chronic inflammation and destruction of joint tissues that occurs in oxalosis and gout. PMID:6292314

  4. The role of polymer nanosurface roughness and submicron pores in improving bladder urothelial cell density and inhibiting calcium oxalate stone formation

    NASA Astrophysics Data System (ADS)

    Chun, Young Wook; Khang, Dongwoo; Haberstroh, Karen M.; Webster, Thomas J.

    2009-02-01

    Synthetic polymers have been proposed for replacing resected cancerous bladder tissue. However, conventional (or nanosmooth) polymers used in such applications (such as poly(ether) urethane (PU) and poly-lactic-co-glycolic acid (PLGA)) often fail clinically due to poor bladder tissue regeneration, low cytocompatibility properties, and excessive calcium stone formation. For the successful reconstruction of bladder tissue, polymer surfaces should be modified to combat these common problems. Along these lines, implementing nanoscale surface features that mimic the natural roughness of bladder tissue on polymer surfaces can promote appropriate cell growth, accelerate bladder tissue regeneration and inhibit bladder calcium stone formation. To test this hypothesis, in this study, the cytocompatibility properties of both a non-biodegradable polymer (PU) and a biodegradable polymer (PLGA) were investigated after etching in chemicals (HNO3 and NaOH, respectively) to create nanoscale surface features. After chemical etching, PU possessed submicron sized pores and numerous nanometer surface features while PLGA possessed few pores and large amounts of nanometer surface roughness. Results from this study strongly supported the assertion that nanometer scale surface roughness produced on PU and PLGA promoted the density of urothelial cells (cells that line the interior of the bladder), with the greatest urothelial cell densities observed on nanorough PLGA. In addition, compared to respective conventional polymers, the results provided evidence that nanorough PU and PLGA inhibited calcium oxalate stone formation; submicron pored nanorough PU inhibited calcium oxalate stone formation the most. Thus, results from the present study suggest the importance of nanometer topographical cues for designing better materials for bladder tissue engineering applications.

  5. Contribution of dietary oxalate to urinary oxalate excretion

    NASA Technical Reports Server (NTRS)

    Holmes, R. P.; Goodman, H. O.; Assimos, D. G.

    2001-01-01

    BACKGROUND: The amount of oxalate excreted in urine has a significant impact on calcium oxalate supersaturation and stone formation. Dietary oxalate is believed to make only a minor (10 to 20%) contribution to the amount of oxalate excreted in urine, but the validity of the experimental observations that support this conclusion can be questioned. An understanding of the actual contribution of dietary oxalate to urinary oxalate excretion is important, as it is potentially modifiable. METHODS: We varied the amount of dietary oxalate consumed by a group of adult individuals using formula diets and controlled, solid-food diets with a known oxalate content, determined by a recently developed analytical procedure. Controlled solid-food diets were consumed containing 10, 50, and 250 mg of oxalate/2500 kcal, as well as formula diets containing 0 and 180 mg oxalate/2500 kcal. Changes in the content of oxalate and other ions were assessed in 24-hour urine collections. RESULTS: Urinary oxalate excretion increased as dietary oxalate intake increased. With oxalate-containing diets, the mean contribution of dietary oxalate to urinary oxalate excretion ranged from 24.4 +/- 15.5% on the 10 mg/2500 kcal/day diet to 41.5 +/- 9.1% on the 250 mg/2500 kcal/day diet, much higher than previously estimated. When the calcium content of a diet containing 250 mg of oxalate was reduced from 1002 mg to 391 mg, urinary oxalate excretion increased by a mean of 28.2 +/- 4.8%, and the mean dietary contribution increased to 52.6 +/- 8.6%. CONCLUSIONS: These results suggest that dietary oxalate makes a much greater contribution to urinary oxalate excretion than previously recognized, that dietary calcium influences the bioavailability of ingested oxalate, and that the absorption of dietary oxalate may be an important factor in calcium oxalate stone formation.

  6. Influence of Ureteral Stone Components on the Outcomes of Electrohydraulic Lithotripsy

    PubMed Central

    Song, Hyeong Cheol; Jung, Ha Bum; Lee, Yong Seong; Lee, Young Goo; Kim, Ki Kyung

    2012-01-01

    Purpose We evaluated the influence of urinary stone components on the outcomes of ureteroscopic removal of stones (URS) by electrohydraulic lithotripsy (EHL) in patients with distal ureteral stones. Materials and Methods Patients with a single distal ureteral stone with a stone size of 0.5 to 2.0 cm that was completely removed by use of EHL were included in the study. Operating time was defined as the time interval between ureteroscope insertion and complete removal of ureteral stones. Ureteral stones were classified into 5 categories on the basis of their main component (that accounting for 50% or more of the stone content) as follows: calcium oxalate monohydrate (COM), calcium oxalate dihydrate, carbonate apatite (CAP), uric acid (UA), and struvite (ST). Results A total of 193 patients (131 males and 62 females) underwent EHL. The mean operating time was 25.18.2 minutes and the mean stone size was 1.150.44 cm. Calcium oxalate stones accounted for 64.8% of all ureteral stones, followed by UA (19.7%), CAP (8.3%), and ST (7.2%) stones. The mean operating time was significantly longer in the UA group (28.68.3 minutes) than in the COM group (24.07.8 minutes, p=0.04). In multivariate analyses, the stone size was negatively associated with the odds ratio (OR) for successful fragmentation. UA as a main component (OR, 0.42; 95% confidence interval, 0.20 to 0.89; p=0.023) was also found to be significantly important as a negative predictive factor of successful fragmentation after adjustment for stone size. Conclusions The results of the present study suggest that successful fragmentation by URS with EHL could be associated with the proportion of the UA component. PMID:23301129

  7. What I Need to Know about Kidney Stones

    MedlinePLUS

    ... on the type of kidney stone you had: Calcium Oxalate Stones reduce sodium reduce animal protein, such as ... Kidney stones are caused by high levels of calcium, oxalate, and phosphorus in the urine. You may have ...

  8. Keep Your Kidneys Clear: Kicking Kidney Stones

    MedlinePLUS

    ... made of the mineral calcium, combined with either oxalate or phosphate. Less common types of stones are ... drinks. For example, people prone to forming calcium oxalate stones should avoid spinach, peanuts and chocolate. People ...

  9. Using Helical CT to Predict Stone Fragility in Shock Wave Lithotripsy (SWL)

    SciTech Connect

    Williams, James C. Jr.; Zarse, Chad A.; Jackson, Molly E.; McAteer, James A.; Lingeman, James E.

    2007-04-05

    Great variability exists in the response of urinary stones to SWL, and this is true even for stones composed of the same mineral. Efforts have been made to predict stone fragility to shock waves using computed tomography (CT) patient images, but most work to date has focused on the use of stone CT number (i.e., Hounsfield units). This is an easy number to measure on a patient stone, but its value depends on a number of factors, including the relationship of the size of the stone to me resolution (i.e., the slicewidth) of the CT scan. Studies that have shown a relationship between stone CT number and failure in SWL are reviewed, and all are shown to suffer from error due to stone size, which was not accounted for in the use of Hounsfield unit values. Preliminary data are then presented for a study of calcium oxalate monohydrate (COM) stones, in which stone structure-rather than simple CT number values-is shown to correlate with fragility to shock waves. COM stones that were observed to have structure by micro CT (e.g., voids, apatite regions, unusual shapes) broke to completion in about half the number of shock waves required for COM stones that were observed to be homogeneous in structure by CT. This result suggests another direction for the use of CT in predicting success of SWL: the use of CT to view stone structure, rather than simply measuring stone CT number. Viewing stone structure by CT requires the use of different viewing windows than those typically used for examining patient scans, but much research to date indicates that stone structure can be observed in the clinical setting. Future clinical studies will need to be done to verify the relationship between stone structure observed by CT and stone fragility in SWL.

  10. Using Helical CT to Predict Stone Fragility in Shock Wave Lithotripsy (SWL)

    NASA Astrophysics Data System (ADS)

    Williams, James C.; Zarse, Chad A.; Jackson, Molly E.; Lingeman, James E.; McAteer, James A.

    2007-04-01

    Great variability exists in the response of urinary stones to SWL, and this is true even for stones composed of the same mineral. Efforts have been made to predict stone fragility to shock waves using computed tomography (CT) patient images, but most work to date has focused on the use of stone CT number (i.e., Hounsfield units). This is an easy number to measure on a patient stone, but its value depends on a number of factors, including the relationship of the size of the stone to me resolution (i.e., the slicewidth) of the CT scan. Studies that have shown a relationship between stone CT number and failure in SWL are reviewed, and all are shown to suffer from error due to stone size, which was not accounted for in the use of Hounsfield unit values. Preliminary data are then presented for a study of calcium oxalate monohydrate (COM) stones, in which stone structurerather than simple CT number valuesis shown to correlate with fragility to shock waves. COM stones that were observed to have structure by micro CT (e.g., voids, apatite regions, unusual shapes) broke to completion in about half the number of shock waves required for COM stones that were observed to be homogeneous in structure by CT. This result suggests another direction for the use of CT in predicting success of SWL: the use of CT to view stone structure, rather than simply measuring stone CT number. Viewing stone structure by CT requires the use of different viewing windows than those typically used for examining patient scans, but much research to date indicates that stone structure can be observed in the clinical setting. Future clinical studies will need to be done to verify the relationship between stone structure observed by CT and stone fragility in SWL.

  11. Natural Abundance 43Ca NMR as a Tool for Exploring Calcium Biomineralization: Renal Stone Formation and Growth

    SciTech Connect

    Bowers, Geoffrey M.; Kirkpatrick, Robert J.

    2011-12-07

    Renal stone diseases are a global health issue with little effective therapeutic recourse aside from surgery and shock-wave lithotripsy, primarily because the fundamental chemical mechanisms behind calcium biomineralization are poorly understood. In this work, we show that natural abundance 43Ca NMR at 21.1 T is an effective means to probe the molecular-level Ca2+ structure in oxalate-based kidney stones. We find that the 43Ca NMR resonance of an authentic oxalate-based kidney stone cannot be explained by a single pure phase of any common Ca2+-bearing stone mineral. Combined with XRD results, our findings suggest an altered calcium oxalate monohydrate-like Ca2+ coordination environment for some fraction of Ca2+ in our sample. The evidence is consistent with existing literature hypothesizing that nonoxalate organic material interacts directly with Ca2+ at stone surfaces and is the primary driver of renal stone aggregation and growth. Our findings show that 43Ca NMR spectroscopy may provide unique and crucial insight into the fundamental chemistry of kidney stone formation, growth, and the role organic molecules play in these processes.

  12. Hyaluronan and Stone Disease

    NASA Astrophysics Data System (ADS)

    Asselman, Marino

    2008-09-01

    Kidney stones cannot be formed as long as crystals are passed in the urine. However, when crystals are retained it becomes possible for them to aggregate and form a stone. Crystals are expected to be formed not earlier than the distal tubules and collecting ducts. Studies both in vitro and in vivo demonstrate that calcium oxalate monohydrate crystals do not adhere to intact distal epithelium, but only when the epithelium is proliferating or regenerating, so that it possesses dedifferentiated cells expressing hyaluronan, osteopontin (OPN) and their mutual receptor CD44 at the apical cell membrane. The polysaccharide hyaluronan is an excellent crystal binding molecule because of its negative ionic charge. We hypothesized that the risk for crystal retention in the human kidney would be increased when tubular cells express hyaluronan at their apical cell membrane. Two different patient categories in which nephrocalcinosis frequently occurs were studied to test this hypothesis (preterm neonates and kidney transplant patients). Hyaluronan (and OPN) expression at the luminal membrane of tubular cells indeed was observed, which preceded subsequent retention of crystals in the distal tubules. Tubular nephrocalcinosis has been reported to be associated with decline of renal function and thus further studies to extend our knowledge of the mechanisms of retention and accumulation of crystals in the kidney are warranted. Ultimately, this may allow the design of new strategies for the prevention and treatment of both nephrocalcinosis and nephrolithiasis in patients.

  13. Physicochemical analysis of urinary stones from Dharmapuri district.

    PubMed

    Aslin Shamema, A; Thanigai Arul, K; Senthil Kumar, R; Narayana Kalkura, S

    2015-01-01

    Nephrolithiasis is a common disease caused by the multifactorial components such as geographical location, bacterial infection, low urine volume, and low intake of water. This disease induces severe metabolic abnormalities in the human body. As the prevalence of this disease was high in Dharmapuri district located in Tamil Nadu, urinary stones removed from the patients pertaining to this district were collected and to identify the toxic elements present in the stones. The presence of functional groups and phases of the stones were analyzed using X-ray diffraction (XRD), Fourier transform Raman spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The majority of stones were found to be calcium oxalate monohydrate (COM) and mixed stones having minor existence of struvite and uric acid. Hexagonal shaped COM crystals, needle shaped uric acid crystals and layered arrangement of struvite crystals in the core region were revealed by Scanning Electron Microscopy (SEM). Thermo Gravimetric Analysis (TGA) was used to determine the thermal stability and the hardness of the stone which was measured using Vickers hardness (HV). The presence of toxic elements in stones such as zirconium and mercury was identified using Energy Dispersive X-ray Spectroscopy (EDS). The EDS analysis showed higher concentration of zirconium in the core region compared to the periphery. The percentage of zirconium was relatively high compared to other toxic elements in the stones. The Vickers hardness results indicated that high HV values in the core region than the periphery and this might be due to the presence of zirconium. PMID:25033236

  14. Physicochemical analysis of urinary stones from Dharmapuri district

    NASA Astrophysics Data System (ADS)

    Aslin Shamema, A.; Thanigai Arul, K.; Senthil Kumar, R.; Narayana Kalkura, S.

    2015-01-01

    Nephrolithiasis is a common disease caused by the multifactorial components such as geographical location, bacterial infection, low urine volume, and low intake of water. This disease induces severe metabolic abnormalities in the human body. As the prevalence of this disease was high in Dharmapuri district located in Tamil Nadu, urinary stones removed from the patients pertaining to this district were collected and to identify the toxic elements present in the stones. The presence of functional groups and phases of the stones were analyzed using X-ray diffraction (XRD), Fourier transform Raman spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The majority of stones were found to be calcium oxalate monohydrate (COM) and mixed stones having minor existence of struvite and uric acid. Hexagonal shaped COM crystals, needle shaped uric acid crystals and layered arrangement of struvite crystals in the core region were revealed by Scanning Electron Microscopy (SEM). Thermo Gravimetric Analysis (TGA) was used to determine the thermal stability and the hardness of the stone which was measured using Vickers hardness (HV). The presence of toxic elements in stones such as zirconium and mercury was identified using Energy Dispersive X-ray Spectroscopy (EDS). The EDS analysis showed higher concentration of zirconium in the core region compared to the periphery. The percentage of zirconium was relatively high compared to other toxic elements in the stones. The Vickers hardness results indicated that high HV values in the core region than the periphery and this might be due to the presence of zirconium.

  15. Rapid vaporization of kidney stones, ex vivo, using a Thulium fiber laser at pulse rates up to 500 Hz with a stone basket

    NASA Astrophysics Data System (ADS)

    Hardy, Luke A.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

    2014-03-01

    The Holmium:YAG laser (? = 2120 nm) is currently the preferred laser for fragmenting kidney stones in the clinic. However, this laser has some limitations, including operation at low pulse rates and a multimode spatial beam profile which prohibits its use with smaller, more flexible optical fibers. Our laboratory is studying the Thulium fiber laser (? = 1908 nm) as an alternative lithotripter. The TFL has several advantages, including lower stone ablation thresholds, use with smaller and more flexible fibers, and operation at arbitrary pulse lengths and pulse rates. Previous studies have reported increased stone ablation rates with TFL operation at higher pulse rates, however, stone retropulsion remains an obstacle to even more efficient stone ablation. This study explores TFL operation at high pulse rates in combination with a stone stabilization device (e.g. stone basket) for improved efficiency. A TFL beam with pulse energy of 35 mJ, pulse duration of 500-?s, and pulse rates of 10-500 Hz was coupled into 100-?m-core, low-OH, silica fibers, in contact mode with uric acid and calcium oxalate monohydrate stones, ex vivo. TFL operation at 500 Hz produced UA and COM stone ablation rates up to 5.0 mg/s and 1.3 mg/s, respectively. High TFL pulse rates produced increased stone ablation rates sufficient for use in the clinic.

  16. Kidney Stones

    PubMed Central

    Kleeman, Charles R.; Coburn, Jack W.; Brickman, Arnold S.; Lee, David B. N.; Narins, Robert G.; Ehrlich, Richard M.

    1980-01-01

    The prevalence of kidney stones has steadily risen during this century; passage of a calculus and a positive family history increase the probability of recurrence. Findings from recent studies on the cause of renal calculi have stressed crystallization and crystal aggregation of stone minerals from supersaturated urine, rather than excessive organic matrix. Absence of normal urine inhibitors of calcium salts is also stressed. Formation of calcium oxalate stones is the major problem. Therapy with decreased calcium and oxalate intake, thiazides, phosphate salts and allopurinol in various combinations has substantially decreased the prevalence of recurrent stones. The rationale for the use of allopurinol is that uric acid salts enhance the tendency for calcium oxalate to crystallize from supersaturated urine. The hypercalciuria seen in 30 percent to 40 percent of patients with oxalate stones is usually caused by intestinal hyperabsorption of calcium. Although patients with uric acid calculi constitute only a small fraction of those in whom stones form, they represent a group in whom good medical therapy, based on sound physiologic principles, has proved extremely successful. Renal tubular syndromes lead to nephrocalcinosis and lithiasis through hypercalciuria, alkaline urine and hypocitraturia, the latter an inhibitor of calcium salt precipitation. Recent advances in surgical techniques are discussed, including the rationale for removing staghorn calculi. The ileal ureter and coagulum pyelolithotomy deserve special emphasis. ImagesFigure 2.Figure 4.Figure 5.Figure 7. PMID:7385835

  17. Relevance of dietary protein concentration and quality as risk factors for the formation of calcium oxalate stones in cats.

    PubMed

    Palack, Nadine; Burmeier, Hannes; Brenten, Thomas; Neumann, Konrad; Zentek, Jrgen

    2014-01-01

    The role of dietary protein for the development of feline calcium oxalate (CaOx) uroliths has not been conclusively clarified. The present study evaluated the effects of a varying dietary protein concentration and quality on critical indices for the formation of CaOx uroliths. Three diets with a high protein quality (10-11 % greaves meal/diet) and a varying crude protein (CP) concentration (35, 44 and 57 % in DM) were compared. Additionally, the 57 % CP diet was compared with a fourth diet that had a similar CP concentration (55 % in DM), but a lower protein quality (34 % greaves meal/diet). The Ca and oxalate (Ox) concentrations were similar in all diets. A group of eight cats received the same diet at the same time. Each feeding period was divided into a 21 d adaptation period and a 7 d sampling period to collect urine. There were increases in urinary volume, urinary Ca concentrations, renal Ca and Ox excretion and urinary relative supersaturation (RSS) with CaOx with increasing dietary protein concentrations. Urinary pH ranged between 634 and 666 among all groups, with no unidirectional effect of dietary protein. Lower renal Ca excretion was observed when feeding the diet with the lower protein quality, however, the underlying mechanism needs further evaluation. In conclusion, although the observed higher urinary volume is beneficial, the increase in urinary Ca concentrations, renal Ca and Ox excretion and urinary RSS CaOx associated with a high-protein diet may be critical for the development of CaOx uroliths in cats. PMID:26101619

  18. Medical therapy, calcium oxalate urolithiasis

    NASA Technical Reports Server (NTRS)

    Ruml, L. A.; Pearle, M. S.; Pak, C. Y.

    1997-01-01

    The development of diagnostic protocols that identify specific risk factors for calcium oxalate nephrolithiasis has led to the formulation of directed medical regimens that are aimed at correcting the underlying metabolic disturbances. Initiation of these treatment programs has reduced markedly the rate of stone formation in the majority of patients who form stones. This article discusses the rationale that underlies the choice of medical therapy for the various pathophysiologic causes of calcium oxalate nephrolithiasis and the appropriate use of available medications.

  19. Medical therapy, calcium oxalate urolithiasis.

    PubMed

    Ruml, L A; Pearle, M S; Pak, C Y

    1997-02-01

    The development of diagnostic protocols that identify specific risk factors for calcium oxalate nephrolithiasis has led to the formulation of directed medical regimens that are aimed at correcting the underlying metabolic disturbances. Initiation of these treatment programs has reduced markedly the rate of stone formation in the majority of patients who form stones. This article discusses the rationale that underlies the choice of medical therapy for the various pathophysiologic causes of calcium oxalate nephrolithiasis and the appropriate use of available medications. PMID:9048856

  20. Chemical decomposition of urinary stones during holmium-laser lithotripsy: II. Evidence for photothermal breakdown

    NASA Astrophysics Data System (ADS)

    Glickman, Randolph D.; Teichman, Joel M. H.; Vassar, George J.; Weintraub, Susan T.; Chan, Kin Foong; Pfefer, T. Joshua; Welch, Ashley J.

    1999-06-01

    Because of the greater than or equal to 250 microsecond pulsewidth emitted by the Ho:YAG laser used in clinical lithotripsy, it is unlikely that stress confinement occurs within the irradiated stones. Experimental data supports a thermal mechanism for Ho:YAG laser stone ablation. Stone fragmentation occurs soon after the onset of the laser pulse, is uncorrelated to cavitation bubble formation or collapse, and is associated with low pressures (cf. part I). The mass- loss of desiccated calcium oxalate monohydrate (COM) stones exposed to 150 J from the Ho:YAG laser in air was 40 plus or minus 12 mg (mean plus or minus 1 s.d.); for hydrated stones in air was 25 plus or minus 9 mg; and for hydrated stones in water was 17 plus or minus 3 mg, p less than .001. These differences indicate that direct absorption of the laser radiation by the stone is required for the most efficient ablation. Lowering the initial temperature of COM or cystine stones also reduced the stone mass-loss following 20 J of delivered laser energy: 2.2 plus or minus 1.1 mg vs 5.2 plus or minus 1.6 mg for COM stones (-80 vs 23 degrees Celsius), and 0.8 plus or minus 0.4 mg vs 2.2 plus or minus 1.1 mg for cystine stones (-80 vs 23 degrees Celsius), p less than or equal to .05. Finally, chemical analysis of the laser-induced stone fragments revealed the presence of thermal breakdown products: CaCO3 from COM; free sulfur and cysteine from cystine; Ca2O7P2 from calcium hydorgen phosphate dihydrate, and cyanide from uric acid.

  1. Aluminum citrate inhibits cytotoxicity and aggregation of oxalate crystals.

    PubMed

    Guo, Chungang; McMartin, Kenneth E

    2007-02-12

    Calcium oxalate monohydrate (COM), which represents a major component of kidney stones, is an end metabolite of ethylene glycol. COM accumulation has been linked with acute renal toxicity in ethylene glycol poisoning. COM injures the kidney either by directly producing cytotoxicity to the kidney cells or by aggregating in the kidney lumen leading to the blockage of urine flow. The present studies were designed to examine whether aluminum citrate could reduce the toxicity of COM. Toxicity was determined in human proximal tubule cells by leakage of lactate dehydrogenase or uptake of ethidium homodimer and in erythrocytes by degree of hemolysis. Aluminum citrate significantly inhibited the leakage of lactate dehydrogenase from human proximal tubule cells and protected against cell death from COM. The inhibitory effect of aluminum citrate was greater than that of other citrate or aluminum salts such as sodium citrate, aluminum chloride, calcium citrate, ammonium citrate or potassium citrate. Aluminum citrate significantly inhibited the aggregation of COM crystals in vitro and decreased red cell membrane damage from COM. Aluminum citrate appeared to directly interact with COM, but not with the cell membrane. As such, aluminum citrate reduced the cytotoxicity by a physico-chemical interaction with the COM surface, and not by dissolving the COM crystals. These studies suggest that aluminum citrate may protect against tissue damage that occurs with high levels of oxalate accumulation, especially in ethylene glycol poisoning and possibly in hyperoxaluric states. PMID:17161516

  2. Oxalate content of cereals and cereal products.

    PubMed

    Siener, Roswitha; Hnow, Ruth; Voss, Susanne; Seidler, Ana; Hesse, Albrecht

    2006-04-19

    Detailed knowledge of food oxalate content is of essential importance for dietary treatment of recurrent calcium oxalate urolithiasis. Dietary oxalate can contribute considerably to the amount of urinary oxalate excretion. Because cereal foods play an important role in daily nutrition, the soluble and total oxalate contents of various types of cereal grains, milling products, bread, pastries, and pasta were analyzed using an HPLC-enzyme-reactor method. A high total oxalate content (>50 mg/100 g) was found in whole grain wheat species Triticum durum (76.6 mg/100 g), Triticum sativum (71.2 mg/100 g), and Triticum aestivum (53.3 mg/100 g). Total oxalate content was comparably high in whole grain products of T. aestivum, that is, wheat flakes and flour, as well as in whole grain products of T. durum, that is, couscous, bulgur, and pasta. The highest oxalate content was demonstrated for wheat bran (457.4 mg/100 g). The higher oxalate content in whole grain than in refined grain cereals suggests that oxalic acid is primarily located in the outer layers of cereal grains. Cereals and cereal products contribute to the daily oxalate intake to a considerable extent. Vegetarian diets may contain high amounts of oxalate when whole grain wheat and wheat products are ingested. Recommendations for prevention of recurrence of calcium oxalate stone disease have to take into account the oxalate content of these foodstuffs. PMID:16608223

  3. Effect of supersaturation ratio and Khella extract on nucleation and morphology of kidney stones

    NASA Astrophysics Data System (ADS)

    Abdel-Aal, E. A.; Daosukho, S.; El-Shall, H.

    2009-04-01

    Induction times in supersaturated calcium oxalate (CaOx)-the major component of most kidney stones-solutions were determined at 37 C using UV-vis spectrometry with and without Khella extract. The slope of the light absorbance measurement curve indicated the inhibition of calcium oxalate nucleation with Khella extract. The induction time was estimated from the time vs. absorbance curve. Khella seeds were obtained from two sources, one in Turkey and one in Egypt. High performance liquid chromatography (HPLC) results showed that only Turkish Khella extract contained khellin and visnagin that are believed to be the active components of the herb. Both extracts contained calcium, magnesium, and oxalate. It was found that both Khella extracts reduced the induction time at every supersaturation ratio. Using an equation that relates induction times and supersaturation ratios, free energy barrier, and critical nuclei radius were calculated. The results revealed that decrease of free energy barrier and critical nuclei radius as supersaturation ratio increased. In addition, the calculated surface energy of calcium oxalate crystals was decreased from 9.01 to 6.79 and 6.40 mJ/m2 with Egyptian Khella extract and Turkish Khella extract, respectively. Scanning electron microscopy (SEM) photomicrographs showed that the control supersaturated CaOx solutions produced CaOx monohydrate (COM) crystals. With the addition of Khella extract, the resulting crystals were modified to calcium oxalate dihydrate (COD) form.

  4. Swietenolide monohydrate

    PubMed Central

    Tan, Seok-Keik; Osman, Hasnah; Wong, Keng-Chong; Fun, Hoong-Kun; Chantrapromma, Suchada

    2008-01-01

    The title compound, a natural b,d-seco-limonoid, C27H34O8H2O, and known as Swietenolide monohydrate, has been isolated from S. macrophylla King. In the molecular structure, the four fused six-membered rings adopt twist-boat (ring A), approximate chair (ring B), envelope (ring C) and half-chair (ring D) conformations. The attached furan ring is essentially planar. OH?O hydrogen bonds and weak CH?O interactions connect the molecules into a two-dimensional network parallel to the (100) plane. CH?? interactions are also observed. PMID:21202901

  5. Food oxalate: factors affecting measurement, biological variation, and bioavailability.

    PubMed

    Massey, Linda K

    2007-07-01

    Food and nutrition professionals provide medical nutrition therapy for patients with kidney stones. If the stones contain oxalate or the patient has been diagnosed with hyperoxaluria, reduction of dietary oxalate may be appropriate. Differences in oxalate values for a single food may be due to analytical methods, and/or biological variation from several sources, including cultivar, time of harvest, and growing conditions. Bioavailability of food oxalate and, thus, urine oxalate, will also be affected by salt forms of oxalate, food processing and cooking methods, meal composition, and the presence of Oxalabacter formigenes in the patient's gut. Dietary advice for reducing urinary oxalate should include both reduction of dietary oxalate and simultaneous consumption of calcium-rich food or supplement to reduce oxalate absorption. PMID:17604750

  6. Acute oxalate nephropathy caused by ethylene glycol poisoning

    PubMed Central

    Seo, Jung Woong; Lee, Jong-Ho; Son, In Sung; Kim, Yong Jin; Kim, Do Young; Hwang, Yong; Chung, Hyun Ah; Choi, Hong Seok; Lim, So Dug

    2012-01-01

    Ethylene glycol (EG) is a sweet-tasting, odorless organic solvent found in many agents, such as anti-freeze. EG is composed of four organic acids: glycoaldehyde, glycolic acid, glyoxylic acid and oxalic acid in vivo. These metabolites are cellular toxins that can cause cardio-pulmonary failure, life-threatening metabolic acidosis, central nervous system depression, and kidney injury. Oxalic acid is the end product of EG, which can precipitate to crystals of calcium oxalate monohydrate in the tubular lumen and has been linked to acute kidney injury. We report a case of EG-induced oxalate nephropathy, with the diagnosis confirmed by kidney biopsy, which showed acute tubular injury of the kidneys with extensive intracellular and intraluminal calcium oxalate monohydrate crystal depositions.

  7. Experimental models of renal calcium stones in rodents.

    PubMed

    Bilbault, Héloïse; Haymann, Jean-Philippe

    2016-03-01

    In human nephrolithiasis, most stones are containing calcium and are located within urinary cavities; they may contain monohydrate calcium oxalate, dihydrate calcium oxalate and/or calcium phosphates in various proportion. Nephrolithiasis may also be associated with nephrocalcinosis, i.e., crystal depositions in tubular lumen and/or interstitium, an entity which suggests specific pathological processes. Several rodents models have been developed in order to study the pathophysiology of intrarenal crystal formation. We review here calcium rodent models classified upon the presence of nephrolithiasis and/or nephrocalcinosis. As rodents are not prone to nephrolithiasis, models require the induction of a long standing hypercalciuria or hyperoxaluria (thus explaining the very few studies reported), conversely to nephrocalcinosis which may occur within hours or days. Whereas a nephrotoxicity leading to tubular injury and regeneration appears as a critical event for crystal retention in nephrocalcinosis models, surprisingly very little is known about the physiopathology of crystal attachment to urothelium in nephrolithiasis. Creating new models of nephrolithiasis especially in different genetic mice strains appears an important challenge in order to unravel the early mechanisms of urinary stone formation in papilla and fornices. PMID:26981444

  8. Experimental models of renal calcium stones in rodents

    PubMed Central

    Bilbault, Héloïse; Haymann, Jean-Philippe

    2016-01-01

    In human nephrolithiasis, most stones are containing calcium and are located within urinary cavities; they may contain monohydrate calcium oxalate, dihydrate calcium oxalate and/or calcium phosphates in various proportion. Nephrolithiasis may also be associated with nephrocalcinosis, i.e., crystal depositions in tubular lumen and/or interstitium, an entity which suggests specific pathological processes. Several rodents models have been developed in order to study the pathophysiology of intrarenal crystal formation. We review here calcium rodent models classified upon the presence of nephrolithiasis and/or nephrocalcinosis. As rodents are not prone to nephrolithiasis, models require the induction of a long standing hypercalciuria or hyperoxaluria (thus explaining the very few studies reported), conversely to nephrocalcinosis which may occur within hours or days. Whereas a nephrotoxicity leading to tubular injury and regeneration appears as a critical event for crystal retention in nephrocalcinosis models, surprisingly very little is known about the physiopathology of crystal attachment to urothelium in nephrolithiasis. Creating new models of nephrolithiasis especially in different genetic mice strains appears an important challenge in order to unravel the early mechanisms of urinary stone formation in papilla and fornices. PMID:26981444

  9. In-vitro studies investigating the stone-fragmenting parameters of the multi-YAG laser

    NASA Astrophysics Data System (ADS)

    Wollin, Timothy A.; Moore, Ronald B.; Tulip, John; McPhee, Malcolm S.

    1996-05-01

    The multi-YAG laser is a multi-purpose surgical laser designed with the ability to emit 1440 nm light in the pulsed mode for ablation of tissue. Preliminary studies have shown that this laser can rapidly ablate urinary calculi. To define the optimal parameters for laser lithotripsy, 60 uric acid (UA) stones and 60 calcium oxalate monohydrate (COM) stones were ablated in a controlled in vitro study. Each stone was fragmented to less than 1.5 mm while varying the pulse energy (0.3 J to 1.5 J) and the pulse frequency (5 Hz to 15 Hz). The mean energy required to fragment a milligram of stone (fragmentation efficacy - J/mg) was calculated for each experimental level and then compared. The pulse frequency did not significantly affect the fragmentation efficacy for the UA stones (p equals 0.4069) or the COM stones (p equals 0.2560) but, it was significantly affected by the pulse energy for both groups (p less than 0.001). In addition, a plateau in the fragmentation efficacy occurred for both stone groups with respect to the pulse energy. For the UA stones, there was no improvement in the efficacy of fragmentation beyond 0.3 J/pulse and for the COM stones, this plateau did not occur until 0.9 J/pulse. Overall, the COM stones required more energy for fragmentation (p equals 0.001), but efficient and rapid ablation was achieved at energies between 0.6 J and 0.9 J/pulse. These results suggest that the multi-YAG laser has the ability to efficiently ablate urinary calculi of variable composition.

  10. Estimation of the oxalate content of foods and daily oxalate intake

    NASA Technical Reports Server (NTRS)

    Holmes, R. P.; Kennedy, M.

    2000-01-01

    BACKGROUND: The amount of oxalate ingested may be an important risk factor in the development of idiopathic calcium oxalate nephrolithiasis. Reliable food tables listing the oxalate content of foods are currently not available. The aim of this research was to develop an accurate and reliable method to measure the food content of oxalate. METHODS: Capillary electrophoresis (CE) and ion chromatography (IC) were compared as direct techniques for the estimation of the oxalate content of foods. Foods were thoroughly homogenized in acid, heat extracted, and clarified by centrifugation and filtration before dilution in water for analysis. Five individuals consuming self-selected diets maintained food records for three days to determine their mean daily oxalate intakes. RESULTS: Both techniques were capable of adequately measuring the oxalate in foods with a significant oxalate content. With foods of very low oxalate content (<1.8 mg/100 g), IC was more reliable than CE. The mean daily intake of oxalate by the five individuals tested was 152 +/- 83 mg, ranging from 44 to 352 mg/day. CONCLUSIONS: CE appears to be the method of choice over IC for estimating the oxalate content of foods with a medium (>10 mg/100 g) to high oxalate content due to a faster analysis time and lower running costs, whereas IC may be better suited for the analysis of foods with a low oxalate content. Accurate estimates of the oxalate content of foods should permit the role of dietary oxalate in urinary oxalate excretion and stone formation to be clarified. Other factors, apart from the amount of oxalate ingested, appear to exert a major influence over the amount of oxalate excreted in the urine.

  11. Acute probiotic ingestion reduces gastrointestinal oxalate absorption in healthy subjects.

    PubMed

    Al-Wahsh, Ismail; Wu, Yan; Liebman, Michael

    2012-06-01

    Both a high dietary oxalate intake and increased intestinal absorption appear to be major causes of elevated urine oxalate, a risk factor for kidney stone formation. A number of recent studies have assessed whether daily ingestion of a probiotic containing oxalate-degrading bacteria could lead to sufficient gut colonization to increase oxalate degradation, thereby reducing urinary oxalate. In contrast, the present study assessed whether simultaneous ingestion of oxalate-degrading probiotic bacteria with a 176 mg oxalate load could lead to decreased urinary oxalate in a population of 11 healthy non-stone formers (8 females, 3 males), aged 21-45 years. The results indicated that both the single and double doses of VSL#3(®) probiotic solutions were effective in reducing urinary oxalate and estimated oxalate absorption with no significant difference between the two probiotic doses. The timing of the reduction in urinary oxalate suggested a small intestinal and possibly gastric reduction in oxalate absorption. Similar to what had been reported for chronic or daily probiotic ingestion, individuals characterized by high oxalate absorption were most likely to experience clinically significant reductions in urinary oxalate in response to acute probiotic ingestion. PMID:21874572

  12. Acute probiotic ingestion reduces gastrointestinal oxalate absorption in healthy subjects.

    TOXLINE Toxicology Bibliographic Information

    Al-Wahsh I; Wu Y; Liebman M

    2012-06-01

    Both a high dietary oxalate intake and increased intestinal absorption appear to be major causes of elevated urine oxalate, a risk factor for kidney stone formation. A number of recent studies have assessed whether daily ingestion of a probiotic containing oxalate-degrading bacteria could lead to sufficient gut colonization to increase oxalate degradation, thereby reducing urinary oxalate. In contrast, the present study assessed whether simultaneous ingestion of oxalate-degrading probiotic bacteria with a 176 mg oxalate load could lead to decreased urinary oxalate in a population of 11 healthy non-stone formers (8 females, 3 males), aged 21-45 years. The results indicated that both the single and double doses of VSL#3(®) probiotic solutions were effective in reducing urinary oxalate and estimated oxalate absorption with no significant difference between the two probiotic doses. The timing of the reduction in urinary oxalate suggested a small intestinal and possibly gastric reduction in oxalate absorption. Similar to what had been reported for chronic or daily probiotic ingestion, individuals characterized by high oxalate absorption were most likely to experience clinically significant reductions in urinary oxalate in response to acute probiotic ingestion.

  13. Bosentan monohydrate

    PubMed Central

    Kaur, Manpreet; Jasinski, Jerry P.; Keeley, Amanda C.; Yathirajan, H. S.; Betz, Richard; Gerber, Thomas; Butcher, Ray J.

    2013-01-01

    In the title compound, C27H29N5O6SH2O {systematic name: 4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl)pyrimidin-4-yl]benzene-1-sulfonamide monohydrate], the dihedral angle between the mean planes of the pyrimidine rings is 27.0?(1). The dihedral angle between the mean planes of the benzene rings is 47.7?(8), forming a U-shaped channel around the chain of twisted pyrimidine rings. The crystal packing is stabilized by OH?O, OH?N and NH?O hydrogen bonds with a single water molecule, and weak OH?N intermolecular interactions between the hydroxy group and one of the pyrimidine rings producing an two-dimensional supramolecular array in the bc plane. The title compound studied was a merohedral twin with the major component being approximately 57%. PMID:23476382

  14. Adhesion of calcium oxalate crystals to Madin-Darby canine kidney cells and some effects of glycosaminoglycans or cell injuries.

    PubMed

    Ebisuno, S; Kohjimoto, Y; Tamura, M; Ohkawa, T

    1995-01-01

    The present investigation studied the quantitative adhesion of calcium oxalate monohydrate (COM) crystals to the surface of Madin-Darby canine kidney cells, which exhibit many characteristics of renal cortical collecting tubule cells. COM crystals adhered to the cell surface, and the attachment showed a time and concentration dependency with plateau. The results suggested that the attachment of microcrystals to the cortical tubular cell might be one of the earliest processes in the formation of kidney stones. Pretreatment with glycosaminoglycans significantly reduced the adherent crystals. Injuries to the Madin-Darby cells induced by 0.1 M HCl and gentamicin resulted in significant decreases of COM crystal adhesion to the cell surface. It was suggested that urinary glycosaminoglycans might play some critical role in preventing crystal adhesion to these cellular membranes and that cell injuries might not be essential for the attachment of microcrystals to the tubular cells. PMID:8521899

  15. Modulation of calcium oxalate crystallization by proteins and small molecules investigated by In Situ Atomic Force Microscopy

    NASA Astrophysics Data System (ADS)

    Qiu, S. R.; Orme, C. A.; Zepeda, S.; Cody, A. M.; Wierzbicki, A.; Hoyer, J. R.; Nancollas, G. H.; de Yoreo, J. J.

    2003-03-01

    Calcium oxalate monohydrate (COM) is known to be a source of pathogenesis in humans where it causes kidney stone disease. The basic modulation of COM by proteins and small molecules mechanism is not well understood. In situ atomic force microscopy (AFM) was used to monitor the COM surface morphology and growth dynamics under controlled growth conditions from pure solutions and those doped with citrate and osteopontin (OPN). AFM results show that OPN, like citrate, inhibits growth on the (-101) face through a step pinning mechanism, especially in the [-10-1] direction. We propose a model that reconciles the step-specific interactions implied by the AFM results with the face-specific predictions of the calculations. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

  16. Stone Composition as a Function of Age and Sex

    PubMed Central

    Rule, Andrew D.; Krambeck, Amy E.; Williams, James C.; Bergstralh, Eric J.; Mehta, Ramila A.; Moyer, Thomas P.

    2014-01-01

    Background and objectives Kidney stones are heterogeneous but often grouped together. The potential effects of patient demographics and calendar month (season) on stone composition are not widely appreciated. Design, setting, participants, & measurements The first stone submitted by patients for analysis to the Mayo Clinic Metals Laboratory during 2010 was studied (n=43,545). Stones were classified in the following order: any struvite, any cystine, any uric acid, any brushite, majority (?50%) calcium oxalate, or majority (?50%) hydroxyapatite. Results Calcium oxalate (67%) was the most common followed by hydroxyapatite (16%), uric acid (8%), struvite (3%), brushite (0.9%), and cystine (0.35%). Men accounted for more stone submissions (58%) than women. However, women submitted more stones than men between the ages of 1019 (63%) and 2029 (62%) years. Women submitted the majority of hydroxyapatite (65%) and struvite (65%) stones, whereas men submitted the majority of calcium oxalate (64%) and uric acid (72%) stones (P<0.001). Although calcium oxalate stones were the most common type of stone overall, hydroxyapatite stones were the second most common before age 55 years, whereas uric acid stones were the second most common after age 55 years. More calcium oxalate and uric acid stones were submitted in the summer months (July and August; P<0.001), whereas the season did not influence other stone types. Conclusions It is well known that calcium oxalate stones are the most common stone type. However, age and sex have a marked influence on the type of stone formed. The higher number of stones submitted by women compared with men between the ages of 10 and 29 years old and the change in composition among the elderly favoring uric acid have not been widely appreciated. These data also suggest increases in stone risk during the summer, although this is restricted to calcium oxalate and uric acid stones. PMID:25278549

  17. Growth retardation of weddellite (calcium oxalate dihydrate) by sodium copper chlorophyllin.

    PubMed

    Tawashi, R; Cousineau, M

    1980-09-01

    We studied the growth of calcium oxalate dihydrate crystals (weddellite) in simulated urine and its transformation into the more stable monohydrate (whewellite). Sodium copper chlorophyllin in a concentration of 100 microgram per ml inhibited the growth of calcium oxalate dihydrate crystals in simulated urine. The size distribution parameters of the dihydrate crystals in the presence and absence of chlorophyllin suggest that soluble chlorophyllin could be of clinical significance in calcium oxalate urolithiasis. PMID:7437122

  18. Biomimetic growth of calcium oxalate crystals: synchrotron X-ray studies

    NASA Astrophysics Data System (ADS)

    Uysal, Ahmet; Stripe, Benjamin; Dutta, Pulak

    2010-03-01

    Oriented crystals of calcium oxalate monohydrate (COM) form one of the major constituents of kidney stones in humans, and these crystals are also found in many plants. It is widely accepted that an organic matrix of lipids and proteins is involved in the crystallization of COM, though their role is not well-understood [1]. Langmuir monolayers of lipids on supersaturated aqueous solutions can be used to mimic the lipid-crystal interface during mineralization. We have studied nucleation and growth of COM crystals under heneicosanoic acid monolayers at the air-water interface. We used synchrotron x-rays in the grazing incidence geometry to determine the structure of the organic monolayer and the orientation of COM crystals in-situ during crystallization. We see that the (-101) faces of COM crystals are parallel to the organic matrix. There is a commensurate relationship between the heneicosanoic acid monolayer and the (-101) crystal face that may be responsible from the oriented growth. Evolution of the monolayer structure with time will be described. [1]S. R. Khan, Calcium Oxalate in Biological Systems, CRC Press, Boca Raton, 1995

  19. Diet, but not oral probiotics, effectively reduces urinary oxalate excretion and calciumoxalate supersaturation

    PubMed Central

    Lieske, John C.; Tremaine, William J.; De Simone, Claudio; O’Connor, Helen M.; Li, Xujian; Bergstralh, Eric J.; Goldfarb, David S.

    2014-01-01

    We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention. PMID:20736987

  20. Mechanisms of human kidney stone formation.

    PubMed

    Evan, Andrew P; Worcester, Elaine M; Coe, Fredric L; Williams, James; Lingeman, James E

    2015-01-01

    The precise mechanisms of kidney stone formation and growth are not completely known, even though human stone disease appears to be one of the oldest diseases known to medicine. With the advent of the new digital endoscope and detailed renal physiological studies performed on well phenotyped stone formers, substantial advances have been made in our knowledge of the pathogenesis of the most common type of stone former, the idiopathic calcium oxalate stone former as well as nine other stone forming groups. The observations from our group on human stone formers and those of others on model systems have suggested four entirely different pathways for kidney stone formation. Calcium oxalate stone growth over sites of Randall's plaque appear to be the primary mode of stone formation for those patients with hypercalciuria. Overgrowths off the ends of Bellini duct plugs have been noted in most stone phenotypes, do they result in a clinical stone? Micro-lith formation does occur within the lumens of dilated inner medullary collecting ducts of cystinuric stone formers and appear to be confined to this space. Lastly, cystinuric stone formers also have numerous small, oval, smooth yellow appearing calyceal stones suggestive of formation in free solution. The scientific basis for each of these four modes of stone formation are reviewed and used to explore novel research opportunities. PMID:25108546

  1. Environmental factors of urinary stones mineralogy, Khouzestan Province, Iran

    NASA Astrophysics Data System (ADS)

    Zarasvandi, Alireza; Carranza, E. J. M.; Heidari, Majid; Mousapour, Esmaeil

    2014-09-01

    Urinary stone diseases in the Khouzestan province (southwest Iran) are growing in number and it required extensive studies on various factors of the urinary stones formation in this province. In this research, in addition to distribution of urinary stones in different areas of province, the role of bioenvironmental (race), climate (temperature) and geology (water hardness) factors in urinary stones diversity has been studied. Mineralogical studied using X-ray diffraction showed that uricite and whewellite are the most frequency mineral phases. Struvite, Cystine, hydroxyapatite, weddellite, and Niahite can be observed as urinary stones, too. These data show that the urinary stone in the Khouzestan province can divide into 7 groups: calcium oxalate, phosphate, calcium oxalate/ phosphate, Urate, Urate/calcium, Urate/calcium oxalate/phosphate, Cystine/calcium oxalate. Also the results which attained from temperature effect investigation on the mineralogy of urinary stones, confirms that from Mediterranean sub-humid climates (northeastern area) to warm and dry climates (south and southwest area), calcium oxalate stones and urate stones concentration decreases and increases respectively. Comparison of data related to the drinking water hardness and mineralogy of urinary stones in different areas of Khouzestan province show that the combination of drinking water (especially water hardness) affects mineralogy of urinary stones in some areas (such az Ramhormoz and Hendijan). Finally, the data suggest that frequency of calcium oxalate in women is more than that of men. Moreover, there is direct relationship between the age (>45 years) and the increase in frequency of Urate minerals.

  2. Component analyses of urinary nanocrystallites of uric acid stone formers by combination of high-resolution transmission electron microscopy, fast Fourier transformation, energy dispersive X-ray spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy.

    PubMed

    Sun, Xin-Yuan; Xue, Jun-Fa; Xia, Zhi-Yue; Ouyang, Jian-Ming

    2015-06-01

    This study aimed to analyse the components of nanocrystallites in urines of patients with uric acid (UA) stones. X-ray diffraction (XRD), Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy (HRTEM), fast Fourier transformation (FFT) of HRTEM, and energy dispersive X-ray spectroscopy (EDS) were performed to analyse the components of these nanocrystallites. XRD and FFT showed that the main component of urinary nanocrystallites was UA, which contains a small amount of calcium oxalate monohydrate and phosphates. EDS showed the characteristic absorption peaks of C, O, Ca and P. The formation of UA stones was closely related to a large number of UA nanocrystallites in urine. A combination of HRTEM, FFT, EDS and XRD analyses could be performed accurately to analyse the components of urinary nanocrystallites. PMID:26023155

  3. Histopathology Predicts the Mechanism of Stone Formation

    NASA Astrophysics Data System (ADS)

    Evan, Andrew P.

    2007-04-01

    About 5% of American women and 12% of men will develop a kidney stone at some time in their life and these numbers appear to be on the rise. Despite years of scientific research into the mechanisms of stone formation and growth, limited advances have been made until recently. Randall's original observations and thoughts on the mechanisms for kidney stone formation have been validated for idiopathic calcium oxalate stone formers (ICSF) but not for most other stone forming groups. Our current studies on selected groups of human stone formers using intraoperative papillary biopsies has shown overwhelming evidence for the presence of Randall's plaque in ICSF and that stone formation and growth are exclusively linked to its availability to urinary ions and proteins. Intense investigation of the plaque-stone junction is needed if we are to understand the factors leading to the overgrowth process on exposed regions of plaque. Such information should allow the development of treatment strategies to block stone formation in ICSF patients. Patients who form brushite stones, or who form apatite stones because of distal renal tubular acidosis (dRTA), or patients with calcium oxalate stones due to obesity bypass procedures, or patients with cystinuria, get plugged inner medullary collecting ducts (IMCD) which leads to total destruction of the lining cells and focal sites of interstitial fibrosis. These stone formers have plaque but at levels equal to or below non-stone formers, which would suggest that they form stones by a different mechanism than do ICSF patients.

  4. In vivo oxalate degradation by liposome encapsulated oxalate oxidase in rat model of hyperoxaluria

    PubMed Central

    Dahiya, Tulika; Pundir, C.S.

    2013-01-01

    Background & objectives: High level of urinary oxalate substantially increases the risk of hyperoxaluria, a significant risk factor for urolithiasis. The primary goal of this study was to reduce urinary oxalate excretion employing liposome encapsulated oxalate oxidase in animal model. Methods: A membrane bound oxalate oxidase was purified from Bougainvillea leaves. The enzyme in its native form was less effective at the physiological pH of the recipient animal. To increase its functional viability, the enzyme was immobilized on to ethylene maleic anhydride (EMA). Rats were injected with liposome encapsulated EMA- oxalate oxidase and the effect was observed on degradation of oxalic acid. Results: The enzyme was purified to apparent homogeneity with 60-fold purification and 31 per cent yield. The optimum pH of EMA-derivative enzyme was 6.0 and it showed 70 per cent of its optimal activity at pH 7.0. The EMA-bound enzyme encapsulated into liposome showed greater oxalate degradation in 15 per cent casein vitamin B6 deficient fed rats as compared with 30 per cent casein vitamin B6 deficient fed rats and control rats. Interpretation & conclusions: EMA-oxalate oxidase encapsulated liposome caused oxalate degradation in experimental hyperoxaluria indicating that the enzyme could be used as a therapeutic agent in hyperoxaluria leading to urinary stones. PMID:23481063

  5. Urinary stones as a novel matrix for human biomonitoring of toxic and essential elements.

    PubMed

    Kuta, J; Smetanová, S; Benová, D; Kořistková, T; Machát, J

    2016-02-01

    Monitoring of body burden of toxic elements is usually based on analysis of concentration of particular elements in blood, urine and/or hair. Analysis of these matrices, however, predominantly reflects short- or medium-term exposure to trace elements or pollutants. In this work, urinary stones were investigated as a matrix for monitoring long-term exposure to toxic and essential elements. A total of 431 samples of urinary calculi were subjected to mineralogical and elemental analysis by infrared spectroscopy and inductively coupled plasma mass spectrometry. The effect of mineralogical composition of the stones and other parameters such as sex, age and geographical location on contents of trace and minor elements is presented. Our results demonstrate the applicability of such approach and confirm that the analysis of urinary calculi can be helpful in providing complementary information on human exposure to trace metals and their excretion. Analysis of whewellite stones (calcium oxalate monohydrate) with content of phosphorus <0.6 % has been proved to be a promising tool for biomonitoring of trace and minor elements. PMID:25736734

  6. Modulation of polyepoxysuccinic acid on crystallization of calcium oxalate

    NASA Astrophysics Data System (ADS)

    Zhang, Yanqing; Tang, Yongming; Xu, Jinqiu; Zhang, Dongqin; Lu, Gang; Jing, Wenheng

    2015-11-01

    The influence of polyepoxysuccinic acid (PESA) on the phase composition and crystal morphology of calcium oxalate was investigated in this paper. It was found that the presence of PESA inhibited the growth of the monoclinic calcium oxalate monohydrate (COM) crystal and promoted the nucleation of the tetragonal calcium oxalate dihydrate (COD). In addition, with the increase in PESA concentration, the aggregation of COD crystals was reduced but the particle size was increased. Under the conditions of low calcium-to-oxalate ratio and high CaOx concentration, PESA could not effectively stabilize the formation of COD. Based on molecular dynamic simulations, the adsorption of PESA on CaOx crystal faces was confirmed.

  7. Characterization of calcium oxalate crystal-induced changes in the secretome of U937 human monocytes.

    PubMed

    Sintiprungrat, Kitisak; Singhto, Nilubon; Thongboonkerd, Visith

    2016-02-23

    In kidney stone disease, migratory monocytes have been found to mediate progressive renal inflammation through the secretion of numerous inflammatory mediators. However, whether calcium oxalate monohydrate (COM), which is the major crystalline compound of kidney stones, has any effects on proteins secreted from monocytes remained largely unknown. The present study aimed to characterize changes in the secretome of U937 human monocytes induced by COM crystals. The viability of cells in serum/protein-free medium was serially evaluated and the data revealed that an exposure time of 16 h was optimal for this study, whereas prolonged incubation for 24 h resulted in declined cell viability. Using this optimal time-point, the secreted proteins recovered from serum/protein-free culture supernatants of controlled and COM-treated cells were resolved in 2-DE and stained with Deep Purple fluorescent dye. Quantitative intensity analysis revealed statistically significant changes in levels of 18 secreted proteins (14 increased and 4 decreased) from COM-treated cells. These significantly altered secreted proteins were then identified by Q-TOF MS and/or MS/MS analyses. Among these, the increased levels of secreted heat shock protein 90 (HSP90), HSP70 and β-actin were confirmed by Western blot analysis. The increased level of extracellular HSP90 was confirmed on the COM-treated cell surface by the immunofluorescence study, whereas the increased secretion of IFN-α was validated by ELISA. Global protein network analysis, literature search and bioinformatics revealed that these significantly altered secreted proteins were involved mainly in immune response and cell survival. Therefore, changes in the secretome of monocytes induced by COM crystals may be related, at least in part, to progressive renal inflammation found in kidney stone disease. PMID:26762788

  8. Internalization of Calcium Oxalate Calculi Developed in Narrow Cavities

    PubMed Central

    Grases, Fèlix; Costa-Bauzá, Antonia; Prieto, Rafel M.; Servera, Antonio

    2014-01-01

    We describe the case of a patient with calcium oxalate monohydrate and calcium oxalate dihydrate calculi occluded in cavities. All those calculi were located inside narrow cavities covered with a thin epithelium that permits their visualization. Urinary biochemical analysis showed high calciuria, not hypercalciuria, hypocitraturia, and a ratio [calcium]/[citrate] >0.33. The existence of cavities of very low urodynamic efficacy was decisive in the formation of such calculi. It is important to emphasize that we observed a thin epithelium covering such cavities, demonstrating that this epithelium may be formed after the development of the calculi through a re-epithelialization process.

  9. Oxalobacter formigenes Colonization and Oxalate Dynamics in a Mouse Model.

    PubMed

    Li, Xingsheng; Ellis, Melissa L; Knight, John

    2015-08-01

    Animal and human studies have provided compelling evidence that colonization of the intestine with Oxalobacter formigenes reduces urinary oxalate excretion and lowers the risk of forming calcium oxalate kidney stones. The mechanism providing protection appears to be related to the unique ability of O. formigenes to rely on oxalate as a major source of carbon and energy for growth. However, much is not known about the factors that influence colonization and host-bacterium interactions. We have colonized mice with O. formigenes OxCC13 and systematically investigated the impacts of diets with different levels of calcium and oxalate on O. formigenes intestinal densities and urinary and intestinal oxalate levels. Measurement of intestinal oxalate levels in mice colonized or not colonized with O. formigenes demonstrated the highly efficient degradation of soluble oxalate by O. formigenes relative to other microbiota. The ratio of calcium to oxalate in diets was important in determining colonization densities and conditions where urinary oxalate and fecal oxalate excretion were modified, and the results were consistent with those from studies we have performed with colonized and noncolonized humans. The use of low-oxalate purified diets showed that 80% of animals retained O. formigenes colonization after a 1-week dietary oxalate deprivation. Animals not colonized with O. formigenes excreted two times more oxalate in feces than they had ingested. This nondietary source of oxalate may play an important role in the survival of O. formigenes during periods of dietary oxalate deprivation. These studies suggest that the mouse will be a useful model to further characterize interactions between O. formigenes and the host and factors that impact colonization. PMID:25979889

  10. Kidney stones

    MedlinePLUS

    ... Calcium stones can also form from combining with phosphate or carbonate. Other types of stones include: Cystine ... uric acid stones) Antibiotics (for struvite stones) Diuretics Phosphate solutions Sodium bicarbonate or sodium citrate Water pills ( ...

  11. A simple method for quantitating the propensity for calcium oxalate crystallization in urine

    NASA Technical Reports Server (NTRS)

    Wabner, C. L.; Pak, C. Y.

    1991-01-01

    To assess the propensity for spontaneous crystallization of calcium oxalate in urine, the permissible increment in oxalate is calculated. The previous method required visual observation of crystallization with the addition of oxalate, this warranted the need for a large volume of urine and a sacrifice in accuracy in defining differences between small incremental changes of added oxalate. Therefore, this method has been miniaturized and spontaneous crystallization is detected from the depletion of radioactive oxalate. The new "micro" method demonstrated a marked decrease (p < 0.001) in the permissible increment in oxalate in urine of stone formers versus normal subjects. Moreover, crystallization inhibitors added to urine, in vitro (heparin or diphosphonate) or in vivo (potassium citrate administration), substantially increased the permissible increment in oxalate. Thus, the "micro" method has proven reliable and accurate in discriminating stone forming from control urine and in distinguishing changes of inhibitory activity.

  12. Determination of Oxalate Content in Herbal Remedies and Dietary Supplements Based on Plant Extracts.

    PubMed

    Siener, Roswitha; López-Mesas, Montserrat; Valiente, Manuel; Blanco, Francisco

    2016-02-01

    Lifestyle, especially diet, is a prominent risk factor that affects the formation of calcium oxalate stones. Urinary oxalate excretion is directly related to the amount of oral intake and intestinal absorption rate of oxalate. This work evaluated the possibility of increasing oxalate ingestion, which could lead to secondary hyperoxaluria, associated with the intake of herbal remedies and dietary supplements containing plant extracts. A wide variety of 17 commercially available drugs and dietary supplements were analyzed using ion chromatography. The results showed remarkable differences in oxalate contents of the extracts. Total oxalate concentrations ranged from 0.03 to 2.2 mg/g in solid samples and from 0.005 to 0.073 mg/mL in liquid samples. The selected herbal remedies and dietary supplements containing plant extracts represent only a low risk for calcium oxalate stone formers, if the recommended daily dose is not exceeded. PMID:26670692

  13. Stone formation and management after bariatric surgery.

    PubMed

    Tarplin, Sarah; Ganesan, Vishnu; Monga, Manoj

    2015-05-01

    Obesity is a significant health concern and is associated with an increased risk of nephrolithiasis, particularly in women. The underlying pathophysiology of stone formation in obese patients is thought to be related to insulin resistance, dietary factors, and a lithogenic urinary profile. Uric acid stones and calcium oxalate stones are common in these patients. Use of surgical procedures for obesity (bariatric surgery) has risen over the past two decades. Although such procedures effectively manage obesity-dependent comorbidities, several large, controlled studies have revealed that modern bariatric surgeries increase the risk of nephrolithiasis by approximately twofold. In patients who have undergone bariatric surgery, fat malabsorption leads to hyperabsorption of oxalate, which is exacerbated by an increased permeability of the gut to oxalate. Patients who have undergone bariatric surgery show characteristic 24 h urine parameters including low urine volume, low urinary pH, hypocitraturia, hyperoxaluria and hyperuricosuria. Prevention of stones with dietary limitation of oxalate and sodium and a high intake of fluids is critical, and calcium supplementation with calcium citrate is typically required. Potassium citrate is valuable for treating the common metabolic derangements as it raises urinary pH, enhances the activity of stone inhibitors, reduces the supersaturation of calcium oxalate, and corrects hypokalaemia. Both pyridoxine and probiotics have been shown in small studies to reduce hyperoxaluria, but further study is necessary to clarify their effects on stone morbidity in the bariatric surgery population. PMID:25850790

  14. Urinary stone composition in Oman: with high incidence of cystinuria.

    PubMed

    Al-Marhoon, Mohammed S; Bayoumi, Riad; Al-Farsi, Yahya; Al-Hinai, Abdullhakeem; Al-Maskary, Sultan; Venkiteswaran, Krishna; Al-Busaidi, Qassim; Mathew, Josephkunju; Rhman, Khalid; Sharif, Omar; Aquil, Shahid; Al-Hashmi, Intisar

    2015-06-01

    Urinary stones are a common problem in Oman and their composition is unknown. The aim of this study is to analyze the components of urinary stones of Omani patients and use the obtained data for future studies of etiology, treatment, and prevention. Urinary stones of 255 consecutive patients were collected at the Sultan Qaboos University Hospital. Stones were analyzed by Fourier transform infrared spectrophotometer. The biochemical, metabolic, and radiological data relating to the patients and stones were collected. The mean age was 41 years, with M:F ratio of 3.7:1. The common comorbidities associated with stone formation were hypertension; diabetes, benign prostate hyperplasia; urinary tract infection; obesity; and atrophic kidney. The common presentation was renal colic and flank pain (96%). Stones were surgically retrieved in 70% of patients. Mean stone size was 9 ± 0.5 mm (range 1.3-80). Stone formers had a BMI ≥ 25 in 56% (P = 0.006) and positive family history of stones in 3.8%. The most common stones in Oman were as follows: Calcium Oxalates 45% (114/255); Mixed calcium phosphates & calcium oxalates 22% (55/255); Uric Acid 16% (40/255); and Cystine 4% (10/255). The most common urinary stones in Oman are Calcium Oxalates. Overweight is an important risk factor associated with stone formation. The hereditary Cystine stones are three times more common in Oman than what is reported in the literature that needs further genetic studies. PMID:25805105

  15. Potential etiologic role of brushite in the formation of calcium (renal) stones

    NASA Astrophysics Data System (ADS)

    Pak, Charles Y. C.

    1981-05-01

    Brushite may play an important regulatory role in the formation of calcium -containing renal stones. The urinary environment from patients with hypercalciuric nephrolithiasis is typically supersaturated and shows an increased propensity for the spontaneous nucleation of brushite. Brushite has been identified in "stone-forming" urine and in stones. This crystalline phase may undergo phase transformation to hydroxyapatite or cause heterogeneous nucleation or epitaxial growth of calcium oxalate. Thus, brushite may also participate in the formation of stones of hydroxypatite or calcium oxalate.

  16. Epitaxy driven interactions at the organic-inorganic interface during biomimetic growth of calcium oxalate

    SciTech Connect

    Uysal, Ahmet; Stripe, Benjamin; Kim, Kyungil; Dutta, Pulak

    2010-10-22

    During oriented biomimetic crystallization of calcium oxalate monohydrate under floating fatty acid monolayers, the (⁻101) surface structure is initially compressed and epitaxial with the monolayer lattice. The surface subsequently relaxes to the bulk structure and the monolayer expands, reestablishing a lattice match. These interactions were observed in situ using synchrotron X-ray diffraction.

  17. Calcium oxalate nephrolithiasis and expression of matrix GLA protein in the kidneys

    PubMed Central

    Khan, Aslam; Wang, Wei; Khan, Saeed R.

    2013-01-01

    Objectives Polymorphism of the gene for matrix GLA protein (MGP), a calcification inhibitor, is associated with nephrolithiasis. However, experimental investigations of MGP role in stone pathogenesis are limited. We determined the effect of renal epithelial exposure to oxalate (Ox), calcium oxalate (CaOx) monohydrate (COM) or hydroxyapatite (HA) crystal on the expression of MGP. Methods MDCK cells in culture were exposed to 0.3, 0.5 or 1 mM Ox and 33, 66 or 133–150 μg/cm2 of COM/HA for 3–72 h. MGP expression and production were determined by Western blotting and densitometric analysis. Enzyme-linked immunosorbent assay was performed to determine MGP release into the medium. Hyperoxaluria was induced in male Sprague–Dawley rats by feeding hydroxyl-L-proline. Immunohistochemistry was performed to detect renal MGP expression. Results Exposure to Ox and crystals led to time- and concentration-dependent increase in expression of MGP in MDCK cells. Cellular response was quicker to crystal exposure than to the Ox, expression being significantly higher after 3-h exposure to COM or HA crystals and more than 6 h of exposure to Ox. MGP expression was increased in kidneys of hyperoxaluric rats particularly in renal peritubular vessels. Conclusion We demonstrate increased expression of MGP in renal tubular epithelial cells exposed to Ox or CaOx crystals as well as the HA crystals. The most significant finding of this study is the increased staining seen in renal peritubular vessels of the hyperoxaluric rats, indicating involvement of renal endothelial cells in the synthesis of MGP. PMID:23475213

  18. Intracrystalline Proteins Promote Dissolution of Urinary Calcium Oxalate Crystals in Cultured Renal Epithelial Cells

    NASA Astrophysics Data System (ADS)

    Grover, Phulwinder K.; Thurgood, Lauren A.; Fleming, David E.; van Bronswijk, Wilhelm; Ryall, Rosemary L.

    2007-04-01

    We have proposed that internalized calcium oxalate (CaOx) crystals containing intracrystalline proteins would be vulnerable to intracellular dissolution. The aims of this study were (1) to measure non-uniform strain and crystallite size in CaOx monohydrate (COM) crystals containing increasing amounts of intracrystalline crystal matrix extract (CME) and (2) to compare the rates of crystal dissolution in Madin-Darby canine kidney (MDCKII) cells. CME was isolated by demineralization of COM crystals generated from human urine. Cold and 14C-oxalate-labelled COM crystals were precipitated from ultrafiltered urine containing CME at final concentrations of 0-5mg/L. Non-uniform strain and crystallite size were determined using synchrotron X-ray diffraction with Rietveld whole-pattern peak fitting and profile analysis, and the protein content of the crystals was analyzed using SDS-PAGE and Western blotting for prothrombin fragment 1. Radiolabeled crystals were added to MDCKII cells and dissolution was expressed as radioactive label released into the medium relative to that in the crystals at zero time. Non-uniform strain increased and crystallite size decreased proportionally with rising CME concentration, reaching saturation between approximately 1 and 5 mg/L, and demonstrating unequivocally the inclusion of increasing quantities of proteins in the crystals. This was confirmed by SDS-PAGE and Western blotting. Crystal dissolution also followed saturation kinetics. These findings were confirmed by field emission scanning electron microscopy (FESEM), which showed that the degree of crystal degradation increased relative to CME concentration. We conclude that intracrystalline proteins enhance intracellular dissolution of CaOx crystals and thus may provide a natural defense against stone pathogenesis.

  19. Intracrystalline urinary proteins facilitate degradation and dissolution of calcium oxalate crystals in cultured renal cells.

    PubMed

    Grover, Phulwinder K; Thurgood, Lauren A; Fleming, David E; van Bronswijk, Wilhelm; Wang, Tingting; Ryall, Rosemary L

    2008-02-01

    We have previously proposed that intracrystalline proteins would increase intracellular proteolytic disruption and dissolution of calcium oxalate (CaOx) crystals. Chauvet MC, Ryall RL. J Struct Biol 151: 12-17, 2005; Fleming DE, van Riessen A, Chauvet MC, Grover PK, Hunter B, van Bronswijk W, Ryall RL. J Bone Miner Res 18: 1282-1291, 2003; Ryall RL, Fleming DE, Doyle IR, Evans NA, Dean CJ, Marshall VR. J Struct Biol 134: 5-14, 2001. The aim of this investigation was to determine the effect of increasing concentrations of intracrystalline protein on the rate of CaOx crystal dissolution in Madin-Darby canine kidney (MDCKII) cells. Crystal matrix extract (CME) was isolated from urinary CaOx monohydrate (COM) crystals. Cold and [14C]oxalate-labeled COM crystals were precipitated from ultrafiltered urine containing 0-5 mg/l CME. Crystal surface area was estimated from scanning electron micrographs, and synchrotron X-ray diffraction was used to determine nonuniform strain and crystallite size. Radiolabeled crystals were added to MDCKII cells and crystal dissolution, expressed as radioactive label released into the medium, was measured. Increasing CME content did not significantly alter crystal surface area. However, nonuniform strain increased and crystallite size decreased in a dose-response manner, both reaching saturation at a CME concentration of 3 mg/ and demonstrating unequivocally the inclusion of increasing quantities of proteins in the crystals. This was confirmed by Western blotting. Crystal dissolution also followed saturation kinetics, increasing proportionally with final CME concentration and reaching a plateau at a concentration of approximately 2 mg/l. These findings were complemented by field emission scanning electron microscopy, which showed that crystal degradation also increased relative to CME concentration. Intracrystalline proteins enhance degradation and dissolution of CaOx crystals and thus may constitute a natural defense against urolithiasis. The findings have significant ramifications in biomineral metabolism and pathogenesis of renal stones. PMID:18077596

  20. Oxalate catabolism in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxalic acid is found in most plant species and can serve beneficial roles that protect the plant from a variety of environmental stresses. Excessive amounts of oxalate, however, can be detrimental to plant health. Thus, careful coordination of oxalate metabolism is needed. Despite the important impa...

  1. The effect of two new semi-synthetic glycosaminoglycans (G871, G872) on the zeta potential of calcium oxalate crystals and on growth and agglomeration.

    PubMed

    Cao, L C; Boev, E R; Schrder, F H; Robertson, W G; Ketelaars, G A; de Bruijn, W C

    1992-06-01

    The effects of two new semisynthetic glycosaminoglycans (GAGs), G871 and G872, on the crystal growth and agglomeration of calcium oxalate monohydrate (COM) were studied in artificial urine in vitro. A constant composition crystallization system and a seeded crystal growth system were used to measure the rate of crystal growth and degree of agglomeration. The zeta potential on the crystal surface was measured using a Coulter DELSA 440 doppler electrophoretic light scattering analyzer. The previously reported GAG analogue, sodium pentosan polysulphate (SPP or SP54), was studied as a reference inhibitor of crystallization using the same systems. All three substances had a concentration-dependent effect on the zeta potential and on the rate of crystal growth and agglomeration of COM in artificial urine. G872 had a significantly greater effect than either G871 or SPP on all the measured parameters. It is suggested that semisynthetic GAGs, such as those reported in this paper may be of use in the prevention of the recurrence of calcium oxalate stones. PMID:1593714

  2. Modification of cement systems with oxalic aldehyde

    NASA Astrophysics Data System (ADS)

    Subbotina, N. V.; Gorlenko, N. P.; Sarkisov, Ju S.; Naumova, L. B.; Minakova, T. S.

    2015-01-01

    The experimental results of physical-chemical properties of composite materials on the basis of cement and wood waste modified by an aquatic solution of oxalic aldehyde are presented in this paper. The injection of a chemical addition agent being in optimal concentration is shown to result in the increase of compressive strength of a cement stone by 30%, that of wood-cement composition - in 7 times. IR spectroscopy investigations, microphotographs of structures, kinetics of samples strength changes are shown.

  3. Thulium fiber laser ablation of kidney stones using a 50-?m-core silica optical fiber

    NASA Astrophysics Data System (ADS)

    Blackmon, Richard L.; Hutchens, Thomas C.; Hardy, Luke A.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

    2015-01-01

    Our laboratory is currently studying the experimental thulium fiber laser (TFL) as a potential alternative laser lithotripter to the gold standard, clinical Holmium:YAG laser. We have previously demonstrated the efficient coupling of TFL energy into fibers as small as 100-?m-core-diameter without damage to the proximal end. Although smaller fibers have a greater tendency to degrade at the distal tip during lithotripsy, fiber diameters (?200 ?m) have been shown to increase the saline irrigation rates through the working channel of a flexible ureteroscope, to maximize the ureteroscope deflection, and to reduce the stone retropulsion during laser lithotripsy. In this study, a 50-?m-core-diameter, 85-?m-outer-diameter, low-OH silica fiber is characterized for TFL ablation of human calcium oxalate monohydrate urinary stones, ex vivo. The 50-?m-core fiber consumes approximately 30 times less cross-sectional area inside the single working channel of a ureteroscope than the standard 270-?m-core fiber currently used in the clinic. The ureteroscope working channel flow rate, including the 50-?m fiber, decreased by only 10% with no impairment of ureteroscope deflection. The fiber delivered up to 15.45.9 W under extreme bending (5-mm-radius) conditions. The stone ablation rate measured 7022 ?g/s for 35-mJ-pulse-energy, 500-?s-pulse-duration, and 50-Hz-pulse-rate. Stone retropulsion and fiber burnback averaged 201336 and 30002600 ?m, respectively, after 2 min. With further development, thulium fiber laser lithotripsy using ultra-small, 50-?m-core fibers may introduce new integration and miniaturization possibilities and potentially provide an alternative to conventional Holmium:YAG laser lithotripsy using larger fibers.

  4. Fish Oil Supplementation and Urinary Oxalate Excretion in Normal Subjects on a Low-oxalate Diet

    PubMed Central

    Lange, Jessica N.; Mufarrij, Patrick W.; Easter, Linda; Knight, John; Holmes, Ross P.; Assimos, Dean G.

    2014-01-01

    OBJECTIVE To determine if fish oil supplementation reduces endogenous oxalate synthesis in healthy subjects. MATERIALS AND METHODS Fifteen healthy nonstone-forming adults participated in this study. Subjects first abstained from using vitamins, medications, or foods enriched in omega-3 fatty acids for 30 days. Next, they collected two 24-hour urine specimens while consuming a self-selected diet. Subjects consumed an extremely low-oxalate and normal-calcium diet for 5 days and collected 24-hour urine specimens on the last 3 days of this diet. Next, the subjects took 2 fish oil capsules containing 650-mg eicosapentaenoic acid and 450-mg docosahexaenoic acid twice daily for 30 days. They consumed a self-selected diet on days 125 and the controlled diet on days 2630. Twenty-four-hour urine samples were collected on days 2830. Excretion levels of urinary analytes including oxalate and glycolate were analyzed. RESULTS Although there was a significant reduction in urinary oxalate, magnesium, and potassium excretions and an increase in uric acid excretion during the controlled dietary phases compared with the self-selected diet, there were no significant differences in their excretion during controlled diet phases with and without fish oil supplementation. CONCLUSION These results suggest that fish oil supplementation does not reduce endogenous oxalate synthesis or urinary oxalate excretion in normal adults during periods of extremely low oxalate intake. However, these results do not challenge the previously described reduction in urinary oxalate excretion demonstrated in normal subjects consuming a moderate amount of oxalate in conjunction with fish oil. PMID:25102784

  5. Aluminum Citrate Prevents Renal Injury from Calcium Oxalate Crystal Deposition

    PubMed Central

    Besenhofer, Lauren M.; Cain, Marie C.; Dunning, Cody

    2012-01-01

    Calcium oxalate monohydrate crystals are responsible for the kidney injury associated with exposure to ethylene glycol or severe hyperoxaluria. Current treatment strategies target the formation of calcium oxalate but not its interaction with kidney tissue. Because aluminum citrate blocks calcium oxalate binding and toxicity in human kidney cells, it may provide a different therapeutic approach to calcium oxalate-induced injury. Here, we tested the effects of aluminum citrate and sodium citrate in a Wistar rat model of acute high-dose ethylene glycol exposure. Aluminum citrate, but not sodium citrate, attenuated increases in urea nitrogen, creatinine, and the ratio of kidney to body weight in ethylene glycol–treated rats. Compared with ethylene glycol alone, the addition of aluminum citrate significantly increased the urinary excretion of both crystalline calcium and crystalline oxalate and decreased the deposition of crystals in renal tissue. In vitro, aluminum citrate interacted directly with oxalate crystals to inhibit their uptake by proximal tubule cells. These results suggest that treating with aluminum citrate attenuates renal injury in rats with severe ethylene glycol toxicity, apparently by inhibiting calcium oxalate’s interaction with, and retention by, the kidney epithelium. PMID:23138489

  6. Urinary stone analysis on 12,846 patients: a report from a single center in China.

    PubMed

    Wu, Wenqi; Yang, Bicheng; Ou, Lili; Liang, Yeping; Wan, Shawpong; Li, Shujue; Zeng, Guohua

    2014-02-01

    We reported a retrospective review of the urinary stone compositions in 12,846 patients. Data on urinary stone compositions analyzed between January 2003 and December 2012 in our center were collected. Infrared spectroscopy was used for stone analysis. Predominant stone component was recorded. Patients were divided into four age groups: 0-18, 19-40, 41-60, and 61-92, and five categories by components. In order to determine the change of stone characteristics with respect to time, data were also divided into two periods, 2003-2007 and 2008-2012. A total of 12,846 stones were included in this study. The age of the patients ranged from 1 to 92 years with 7,736 males and 5,110 females. Stone made of single component was rare, 2.61%. Calcium oxalate stone was the most common component at 82.56%. Calcium oxalate and uric acid stones were more common in male than in female. The incidence of calcium phosphate stones and uric acid stones had increased during the past 5 years, while calcium oxalate stones decreased. We found the highest incidence of stone disease in the 41-60 years old group and the lowest in the 1-18 years old for both genders. Calcium oxalate was the dominant component in every group but was more prevalent in 19-40 years group. The percentage of magnesium ammonium phosphate stone and uric acid stone increased with age. PMID:24362574

  7. The effect of verapamil and thiazide in the prevention of renal stone formation.

    PubMed

    Halabe, A; Wong, N L; Sutton, R A

    1990-01-01

    The effect of the calcium antagonist verapamil, and of thiazide, a well accepted treatment in the prevention of calcium oxalate renal stones, were examined in an experimental renal stone model. Calcium oxalate stones were induced by the synthetic metabolite of vitamin D3, the alpha-OH-vitamin D3 plus ethylene glycol fed rats. A significant decrease in urinary calcium and oxalate was observed following verapamil treatment. Thiazide significantly decreased urinary calcium, but unlike verapamil, did not decrease urinary oxalate. However, no differences in the radiological findings or in the calcium or magnesium content of the kidneys were observed. Although several animal models have been described for the study of calcium oxalate stones, none has yet been proven useful for the evaluation of stone therapy. PMID:2339485

  8. Mineralogy and chemistry of urinary stones: patients from North Jordan.

    PubMed

    Abboud, Iyad Ahmed

    2008-10-01

    Urinary stone diseases are increasing in the Middle East. The majority of urinary stone cases are found in the northern part of the country. Stone samples taken from patients living in the Irbid area were collected from Princess Basma Hospital. The present study concentrates on the mineralogical and chemical composition of the urinary stones and on the effective environmental factors that assist in developing the different types of urinary stones. Using X-ray diffraction techniques, the mineralogical composition of the urinary stones was found to be as follows: oxalate, cholesten, and uric acid, with cystine stones occuring more frequently than the others. Cholesten and calcium oxalate stones are the most dominant types of stones. Calcium oxalate is the most common type of oxalate stone. Calcium oxalate is represented in: whewellite, wheddellite, and calcium carbonate oxalate hydrate minerals, in addition to other minerals such as brushite, ammonium phosphate, vaterite, valleriite, and bobierrite from other types of stones. Bobierrite (phosphate group) is a new mineral reported in urinary stones, and this has not been determined in any previous study worldwide. Apatite (calcium phosphate) is deduced using scanning electron microscope (SEM) images. The SEM technique determined crystal forms and systems, shapes, morphological features, and the names of the minerals forming urine stones, while optical properties are studied by polarizing microscope. X-ray fluorescence technique determined the concentrations of major and some trace elements. It revealed that Ca is the main constituent of the urinary stones, especially those composed of calcium oxalate and calcium phosphate. The concentration of trace elements was Ba = 1.57, P = 3.61, Fe = 1.78, S = 2.08, Zr = 4.63, Mo = 3.92, Cu = 1.89, Co = 1.56, and F = 4.2% and was higher in the urinary stones of Jordanian patients than in foreigners in the country. Questionnaires completed by patients suggest that the most significant factors directly effecting the formation of stones are water, climate conditions, food rich in protein and rich in different chemicals. Moreover, some drugs and diseases might also help in developing other stones. PMID:18064405

  9. Isolation and characterizations of oxalate-binding proteins in the kidney

    SciTech Connect

    Roop-ngam, Piyachat; Chaiyarit, Sakdithep; Pongsakul, Nutkridta; Thongboonkerd, Visith

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer The first large-scale characterizations of oxalate-binding kidney proteins. Black-Right-Pointing-Pointer The recently developed oxalate-conjugated EAH Sepharose 4B beads were applied. Black-Right-Pointing-Pointer 38 forms of 26 unique oxalate-binding kidney proteins were identified. Black-Right-Pointing-Pointer 25/26 (96%) of identified proteins had 'L-x(3,5)-R-x(2)-[AGILPV]' domain. -- Abstract: Oxalate-binding proteins are thought to serve as potential modulators of kidney stone formation. However, only few oxalate-binding proteins have been identified from previous studies. Our present study, therefore, aimed for large-scale identification of oxalate-binding proteins in porcine kidney using an oxalate-affinity column containing oxalate-conjugated EAH Sepharose 4B beads for purification followed by two-dimensional gel electrophoresis (2-DE) to resolve the recovered proteins. Comparing with those obtained from the controlled column containing uncoupled EAH-Sepharose 4B (to subtract the background of non-specific bindings), a total of 38 protein spots were defined as oxalate-binding proteins. These protein spots were successfully identified by quadrupole time-of-flight mass spectrometry (MS) and/or tandem MS (MS/MS) as 26 unique proteins, including several nuclear proteins, mitochondrial proteins, oxidative stress regulatory proteins, metabolic enzymes and others. Identification of oxalate-binding domain using the PRATT tool revealed 'L-x(3,5)-R-x(2)-[AGILPV]' as a functional domain responsible for oxalate-binding in 25 of 26 (96%) unique identified proteins. We report herein, for the first time, large-scale identification and characterizations of oxalate-binding proteins in the kidney. The presence of positively charged arginine residue in the middle of this functional domain suggested its significance for binding to the negatively charged oxalate. These data will enhance future stone research, particularly on stone modulators.

  10. Total and soluble oxalate content of some Indian spices.

    PubMed

    Ghosh Das, Sumana; Savage, G P

    2012-06-01

    Spices, such as cinnamon, cloves, cardamom, garlic, ginger, cumin, coriander and turmeric are used all over the world as flavouring and colouring ingredients in Indian foods. Previous studies have shown that spices contain variable amounts of total oxalates but there are few reports of soluble oxalate contents. In this study, the total, soluble and insoluble oxalate contents of ten different spices commonly used in Indian cuisine were measured. Total oxalate content ranged from 194 (nutmeg) to 4,014 (green cardamom) mg/100 g DM, while the soluble oxalate contents ranged from 41 (nutmeg) to 3,977 (green cardamom) mg/100 g DM. Overall, the percentage of soluble oxalate content of the spices ranged from 4.7 to 99.1% of the total oxalate content which suggests that some spices present no risk to people liable to kidney stone formation, while other spices can supply significant amounts of soluble oxalates and therefore should be used in moderation. PMID:22492273

  11. A Case of Recurrent Renal Aluminum Hydroxide Stone

    PubMed Central

    Cak?roglu, Basri; Dogan, Akif Nuri; Tas, Tuncay; Gozukucuk, Ramazan; Uyanik, Bekir Sami

    2014-01-01

    Renal stone disease is characterized by the differences depending on the age, gender, and the geographic location of the patients. Seventy-five percent of the renal stone components is the calcium (Ca). The most common type of the stones is the Ca oxalate stones, while Ca phosphate, uric acid, struvite, and sistine stones are more rarely reported. Other than these types, triamterene, adenosine, silica, indinavir, and ephedrine stones are also reported in the literature as case reports. However, to the best of our knowledge, aluminum hydroxide stones was not reported reported before. Herein we will report a 38-years-old woman with the history of recurrent renal colic disease whose renal stone was determined as aluminum hydroxide stone in type. Aluminum mineral may be considered in the formation of kidney stones as it is widely used in the field of healthcare and cosmetics. PMID:25013740

  12. Isolation and prevention of calcium oxalate-induced apoptotic death and oxidative stress in MDCK cells by diosgenin.

    PubMed

    Saha, Sarmistha; Goswami, Gagan; Pandrangi, Anupama

    2014-10-16

    Calcium oxalate monohydrate (COM) has been shown to be the most frequent constituent of kidney stones. The interactions of cells with COM crystals produce a variety of physiological and pathological changes including the development of oxidative stress, cellular injury and apoptosis. On the other hand, diosgenin, a steroidal sapogenin, is well known for its antioxidant activity. Therefore, the aim of this study was to evaluate whether diosgenin protects MDCK renal epithelial cells from COM-induced apoptotic death. Diosgenin was isolated from fruits of Solanum xanthocarpum by silica gel column chromatography. It was obtained in high yields (1.23%) and the purity was ascertained by HPTLC analysis. Characterization of diosgenin was done by mp, UV-visible spectrophotometry, elemental analysis, FT-IR, (1)H NMR and (13)C NMR analysis. Cells were co-incubated with COM (80?g/cm(2)) and diosgenin (2.5, 5, 7.5 and 10?g/mL) for 24h. It was found that diosgenin attenuated the apoptotic death induced by COM as measured in terms of cell viability, caspase -9/3 activities and DNA fragmentation percent. The inhibitory role of diosgenin on caspase -9/3 activities was also analyzed using molecular docking experiments, which showed interactions to their active sites by H-bonds. Diosgenin also attenuated the increase in lipid peroxidation and glutathione depletion induced by COM crystals. In conclusion, the preventive effect of diosgenin is associated to the inhibition of oxidative stress and caspases. PMID:25446497

  13. In vivo Drosophilia genetic model for calcium oxalate nephrolithiasis

    PubMed Central

    Hirata, Taku; Cabrero, Pablo; Berkholz, Donald S.; Bondeson, Daniel P.; Ritman, Erik L.; Thompson, James R.; Dow, Julian A. T.

    2012-01-01

    Nephrolithiasis is a major public health problem with a complex and varied etiology. Most stones are composed of calcium oxalate (CaOx), with dietary excess a risk factor. Because of complexity of mammalian system, the details of stone formation remain to be understood. Here we have developed a nephrolithiasis model using the genetic model Drosophila melanogaster, which has a simple, transparent kidney tubule. Drosophilia reliably develops CaOx stones upon dietary oxalate supplementation, and the nucleation and growth of microliths can be viewed in real time. The Slc26 anion transporter dPrestin (Slc26a5/6) is strongly expressed in Drosophilia kidney, and biophysical analysis shows that it is a potent oxalate transporter. When dPrestin is knocked down by RNAi in fly kidney, formation of microliths is reduced, identifying dPrestin as a key player in oxalate excretion. CaOx stone formation is an ancient conserved process across >400 My of divergent evolution (fly and human), and from this study we can conclude that the fly is a good genetic model of nephrolithiasis. PMID:22993075

  14. Treatment and prevention of kidney stones: an update.

    PubMed

    Frassetto, Lynda; Kohlstadt, Ingrid

    2011-12-01

    The incidence of nephrolithiasis (kidney stones) is rising worldwide, especially in women and with increasing age. Kidney stones are associated with chronic kidney disease. Preventing recurrence is largely specific to the type of stone (e.g., calcium oxalate, calcium phosphate, cystine, struvite [magnesium ammonium phosphate]), and uric acid stones); however, even when the stone cannot be retrieved, urine pH and 24-hour urine assessment provide information about stone-forming factors that can guide prevention. Medications, such as protease inhibitors, antibiotics, and some diuretics, increase the risk of some types of kidney stones, and patients should be counseled about the risks of using these medications. Managing diet, medication use, and nutrient intake can help prevent the formation of kidney stones. Obesity increases the risk of kidney stones. However, weight loss could undermine prevention of kidney stones if associated with a high animal protein intake, laxative abuse, rapid loss of lean tissue, or poor hydration. For prevention of calcium oxalate, cystine, and uric acid stones, urine should be alkalinized by eating a diet high in fruits and vegetables, taking supplemental or prescription citrate, or drinking alkaline mineral waters. For prevention of calcium phosphate and struvite stones, urine should be acidified; cranberry juice or betaine can lower urine pH. Antispasmodic medications, ureteroscopy, and metabolic testing are increasingly being used to augment fluid and pain medications in the acute management of kidney stones. PMID:22150656

  15. The role of Randall plaques on kidney stone formation

    PubMed Central

    2014-01-01

    Randalls plaque is microscopically a plaque of calcium deposited in the interstitial tissue of the renal papilla. These plaques are thought to serve as a nidus for urinary stone formation. Large amounts of Randalls plaque are unique to idiopathic calcium oxalate stone formers. Although Randalls plaques can be found in other stone formers, only in idiopathic calcium oxalate stone formers, the detailed mechanism of stone overgrow on plaque was thoroughly studied. Calcification is invariably located in the basement membrane of the loops of Henle and from there plaques spread through the interstitium toward urothelium. Within the basement membrane, mineral deposits are individual laminated particles in which zones of crystal and organic matrix overlay each other. In the interstitium, the particles appear to fuse on the collagen bundles to form a syncytium of crystal islands in an organic sea. By loss of integrity of urothelium, regions of plaque are exposed to urine. The exposed surface will touch and be covered by molecules of urine origin, including osteopontin, Tamm Horsfall protein, and crystals formed under urine supersaturations, resulting in a ribbon of alternating matrix and crystal. Eventually crystallization escapes from matrix modulation and crystals extend outward into the space of urine and begin to form a calcium oxalate stone proper. Randalls plaque plays an important role and is prerequisite of kidney stone formation in idiopathic calcium oxalate stone formers. PMID:26816774

  16. Variability of Oxalobacter Formigenes and Oxalate in Stool Samples

    PubMed Central

    Prokopovich, Sergey; Knight, John; Assimos, Dean G.; Holmes, Ross P.

    2009-01-01

    Purpose The intestinal organism Oxalobacter formigenes is unique in using oxalate as its primary carbon and energy source. Intestinal colonization with O. formigenes may have clinical significance by decreasing intestinal oxalate and its absorption, thereby influencing the concentration of oxalate in plasma and urine, and the development of calcium oxalate stone disease. Because the oxalate content of the diet varies considerably, we hypothesized that the number of O. formigenes and amount of oxalate would vary in feces. Materials and Methods To enumerate the number of O. formigenes in feces an accurate and reproducible real-time polymerase chain reaction assay was developed to quantify O. formigenes DNA. Stool samples were obtained from 10 colonized individuals to determine the levels of O. formigenes by this assay and the oxalate content by ion chromatography. Results Concentrations of O. formigenes ranged from lower than the limit of detection of 5 103 to 1.04 109 cells per gm stool. The total oxalate content of stool samples varied from 0.1 to 1.8 mg/gm and fecal water oxalate varied from 60 to 600 ?M. All parameters measured varied within each stool collection, among stool collections on different days and among individuals. Notably in 7 of 10 individuals at least 1 stool sample contained no detectable O. formigenes. In addition, 7 of 10 subjects had a fecal colonization of less than 4 104 per gm stool. Conclusions This study demonstrates that there is intrastool and interstool sample variability in the amount of O. formigenes measured by real-time polymerase chain reaction that did not correlate with the quantity of oxalate in stool. Most subjects had a fecal colonization of less than 4 104 per gm stool. PMID:17870112

  17. Bladder stones

    MedlinePLUS

    Stones - bladder; Urinary tract stones; Bladder calculi ... Benway BM, Bhayani SM. Lower urinary tract calculi. In: Wein AJ, ed. Campbell-Walsh Urology . 10th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 89. Sharma R, Dill CE, Gelman DY. Urinary ...

  18. Venlafaxine besylate monohydrate

    PubMed Central

    Corvalan, Carolina H.; Vega, Daniel R.

    2013-01-01

    The title compound {systematic name: [2-(1-hydroxycyclohexyl)-2-(4-methoxyphenyl)ethyl]dimethylazanium benzenesulfonate monohydrate}, C17H28NO2 +C6H5O3S?H2O, is a besylate salt hydrate of the antidepressant drug venlafaxine. In the crystal, besylate anions and water molecules self-assemble, forming hydrogen-bonded dimers linked around inversion centers, with graph set R 4 4(6). The crystal packing features a chain of alternate dimers and venlafaxine cations in the b-axis direction with the components linked by OH?O hydrogen bonds and CH?O and CH?? interactions. This is the first example of a venlafaxine cation with a closed conformation, as it features an intramolecular NH?O interaction involving the protonated N atom. PMID:24454196

  19. Deacetylnomilin monohydrate

    PubMed Central

    Li, Guo-Qiang; Ye, Yong-Shu; Yang, Yi-Ting; Luo, Hu-Jie; Li, Yao-Lan

    2011-01-01

    In the title compound (systematic name 1-hydroxy-1,2-dihydroobacunoic acid 3,4-lactone monohydrate), C26H32O8H2O, the dihedral angles between the planes of the ester groups and the furan plane are 43.06?(12) and 56.06?(7), while that between the furan plane and the keto group is 58.50?(9). The A/B, B/C and C/D ring junctions are all trans-fused. Intermolecular OH?O hydrogen bonds between the hydroxy and carbonyl groups and the water molecule give rise to a three-dimensional structure. PMID:22065825

  20. Effect of Cystone on Urinary Composition and Stone Formation Over a One Year Period

    PubMed Central

    Erickson, S. B.; Vrtiska, T. J.; Lieske, J. C.

    2014-01-01

    Kidney stones are a common problem for which inadequate prevention exists. We recruited ten recurrent kidney stone formers with documented calcium oxalate stones into a two phased study to assess safety and effectiveness of Cystone, an herbal treatment for prevention of kidney stones. The first phase was a randomized double-blinded 12 week cross over study assessing the effect of Cystone vs. placebo on urinary supersaturation. The second phase was an open label one year study of Cystone to determine if renal stone burden decreased, as assessed by quantitative and subjective assessment of CT. Results revealed no statistically significant effect of Cystone on urinary composition short (6 weeks) or long (52 weeks) term. Average renal stone burden increased rather than decreased on Cystone. Therefore, this study does not support the efficacy of Cystone to treat calcium oxalate stone formers. Future studies will be needed to assess effects on stone passage, or on other stone types. PMID:21419609

  1. Bifidobacterium animalis subsp. lactis decreases urinary oxalate excretion in a mouse model of primary hyperoxaluria.

    PubMed

    Klimesova, Klara; Whittamore, Jonathan M; Hatch, Marguerite

    2015-04-01

    Hyperoxaluria significantly increases the risk of calcium oxalate kidney stone formation. Since several bacteria have been shown to metabolize oxalate in vitro, including probiotic bifidobacteria, we focused on the efficiency and possible mechanisms by which bifidobacteria can influence oxalate handling in vivo, especially in the intestines, and compared these results with the reported effects of Oxalobacter formigenes. Bifidobacterium animalis subsp. lactis DSM 10140 and B. adolescentis ATCC 15703 were administered to wild-type (WT) mice and to mice deficient in the hepatic enzyme alanine-glyoxylate aminotransferase (Agxt(-/-), a mouse model of Primary Hyperoxaluria) that were fed an oxalate-supplemented diet. The administration of B. animalis subsp. lactis led to a significant decrease in urinary oxalate excretion in WT and Agxt(-/-) mice when compared to treatment with B. adolescentis. Detection of B. animalis subsp. lactis in feces revealed that 3 weeks after oral gavage with the bacteria 64% of WT mice, but only 37% of Agxt(-/-) mice were colonized. Examining intestinal oxalate fluxes showed there were no significant changes to net oxalate secretion in colonized animals and were therefore not associated with the changes in urinary oxalate excretion. These results indicate that colonization with B. animalis subsp. lactis decreased urinary oxalate excretion by degrading dietary oxalate thus limiting its absorption across the intestine but it did not promote enteric oxalate excretion as reported for O. formigenes. Preventive or therapeutic administration of B. animalis subsp. lactis appears to have some potential to beneficially influence dietary hyperoxaluria in mice. PMID:25269440

  2. KIDNEY STONE INCIDENCE AND METABOLIC URINARY CHANGES AFTER MODERN BARIATRIC SURGERY: REVIEW OF CLINICAL STUDIES, EXPERIMENTAL MODELS, AND PREVENTION STRATEGIES

    PubMed Central

    Canales, Benjamin K.; Hatch, Marguerite

    2014-01-01

    Bariatric surgery has been associated with increased metabolic kidney stone risk and post-operative stone formation. A MEDLINE search, performed for articles published between January 2005 and November 2013, identified 24 pertinent studies containing 683 bariatric patients with 24-hour urine profiles, 6,777 bariatric patients with kidney stone incidence, and 7,089 non-stone forming controls. Of all procedures reviewed, only Roux-en-Y gastric bypass (RYGB) was linked to post-operative kidney stone development, increasing stone incidence two-fold in non-stone formers (8.5%) and four-fold in patients with previous stone history (16.7%). High quality evidence from 7 studies (n=277 patients) before and after RYGB identified the following post-RYGB urinary lithogenic risk factors: 30% reduction in urine volume (the main driver of urinary crystal saturation), 40% reduction in urinary citrate (a potent stone inhibitor), and 50% increase in urinary oxalate (a stone promotor). Based on this, a summary of strategies to reduce calcium oxalate stone risk following RYGB is provided. Furthermore, recent experimental RYGB studies are assessed for insights into the pathophysiology of oxalate handling, and the literature in gut anion (oxalate) transport is reviewed. Finally, as a potential probiotic therapy for hyperoxaluria, primary data from our laboratory is presented, demonstrating a 70% reduction in urinary oxalate levels in four experimental RYGB animals after colonization with Oxalobacter formigines, a non-pathogenic gut commensal that uses oxalate as an energy source. Overall, urine profiles and kidney stone risk following bariatric surgery appear modifiable by dietary adjustments, appropriate supplementation, and lifestyle changes. For hyperoxaluria resistant to dietary oxalate restriction and calcium binding, well-designed human investigations are needed to identify additional means of lowering urinary oxalate, such as Oxalobacter colonization or empiric pyridoxine therapy. Further investigations are also needed to determine tolerability and compliance of stone prevention strategies, such as citrate supplementation and hydration, in this population. PMID:24969092

  3. Developing strategies to improve the nutritional quality and production of plant foods through manipulation of calcium oxalate formation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The production of oxalate commonly occurs in numerous organisms. Oxalate negatively affects human health by acting as an antinutrient affecting calcium bioavailability and/or contributing to the pathological condition of urinary stone formation where it is a primary component. In some microbes, ox...

  4. Nephrolithiasis: Molecular Mechanism of Renal Stone Formation and the Critical Role Played by Modulators

    PubMed Central

    Aggarwal, Kanu Priya; Narula, Shifa; Kakkar, Monica

    2013-01-01

    Urinary stone disease is an ailment that has afflicted human kind for many centuries. Nephrolithiasis is a significant clinical problem in everyday practice with a subsequent burden for the health system. Nephrolithiasis remains a chronic disease and our fundamental understanding of the pathogenesis of stones as well as their prevention and cure still remains rudimentary. Regardless of the fact that supersaturation of stone-forming salts in urine is essential, abundance of these salts by itself will not always result in stone formation. The pathogenesis of calcium oxalate stone formation is a multistep process and essentially includes nucleation, crystal growth, crystal aggregation, and crystal retention. Various substances in the body have an effect on one or more of the above stone-forming processes, thereby influencing a person's ability to promote or prevent stone formation. Promoters facilitate the stone formation while inhibitors prevent it. Besides low urine volume and low urine pH, high calcium, sodium, oxalate and urate are also known to promote calcium oxalate stone formation. Many inorganic (citrate, magnesium) and organic substances (nephrocalcin, urinary prothrombin fragment-1, osteopontin) are known to inhibit stone formation. This review presents a comprehensive account of the mechanism of renal stone formation and the role of inhibitors/promoters in calcium oxalate crystallisation. PMID:24151593

  5. Uranyl formate monohydrate spectroscopy

    SciTech Connect

    Porter, J.T. II; Muller, C.H. III; West, W.P.; Malley, M.M.

    1983-10-01

    We report the fluorescence excitation and emission spectra of normal and isotopically labeled uranyl formate monohydrate powder, UO/sub 2/(HCOO)/sub 2/.H/sub 2/O, at 4.2/sup 0/K. Dual fluorescence from the two lowest excited states, I and II, occurs in this compound giving rise to a temperature-dependent lifetime. The lowest vibronic levels are assigned on the basis of the observed oxygen and uranium isotope shifts. The unusual activity and relative frequencies of the symmetric and asymmetric O-U-O stretches in the excited state and can be successfully predicted with the addition of a bond-bond interaction term in addition to the usual valence bond potential. The kinetics of nonresonant energy transfer between isotopic /sup x/OU/sup y/O/sup +2/ antitraps and the U/sup 16/O/sub 2//sup +2/ lattice were measured over the range from 1.7 to 4.2/sup 0/K. The observed rates are in agreement with a quadrupole-quadrupole coupling mechanism accompanied by one and two phonon processes which compensate for the energy defect. The asymmetric lineshapes, broader linewidths and tenfold reduction of absorption intensity for the U/sup 16/O/sub 2//sup +2/ lattice compared to the isolated isotopically doped uranyl ions are attributed to the collective nature of the excited state for the majority species.

  6. Urine citrate and renal stone disease.

    PubMed Central

    Goldberg, H; Grass, L; Vogl, R; Rapoport, A; Oreopoulos, D G

    1989-01-01

    Calcium stone disease is attributable to supersaturation of the urine with calcium and other salts, the presence of substances that promote crystallization and a deficiency of inhibitors of crystallization. Citrate is a potent inhibitor of calcium oxalate and calcium phosphate stone formation whose excretion is diminished in some patients with stone disease owing to idiopathic causes or secondary factors such as bowel disease and use of thiazides. The pH within the proximal tubule cells is an important determinant of citrate excretion. Multivariate analysis has shown that the urine concentrations of calcium and citrate are the most important factors in stone formation. In uncontrolled studies potassium citrate, which increases urinary citrate excretion, appears to be promising as a therapeutic agent for patients with stone disease and hypocitraturia refractory to other treatment. On the other hand, there are potential drawbacks to sodium alkali therapy, such as the precipitation of calcium phosphates. PMID:2665909

  7. Kidney stone erosion by micro scale hydrodynamic cavitation and consequent kidney stone treatment.

    PubMed

    Perk, Osman Yavuz; Şeşen, Muhsincan; Gozuacik, Devrim; Koşar, Ali

    2012-09-01

    The objective of this study is to reveal the potential of micro scale hydrodynamic bubbly cavitation for the use of kidney stone treatment. Hydrodynamically generated cavitating bubbles were targeted to the surfaces of 18 kidney stone samples made of calcium oxalate, and their destructive effects were exploited in order to remove kidney stones in in vitro experiments. Phosphate buffered saline (PBS) solution was used as the working fluid under bubbly cavitating conditions in a 0.75 cm long micro probe of 147 μm inner diameter at 9790 kPa pressure. The surface of calcium oxalate type kidney stones were exposed to bubbly cavitation at room temperature for 5 to 30 min. The eroded kidney stones were visually analyzed with a high speed CCD camera and using SEM (scanning electron microscopy) techniques. The experiments showed that at a cavitation number of 0.017, hydrodynamic bubbly cavitation device could successfully erode stones with an erosion rate of 0.31 mg/min. It was also observed that the targeted application of the erosion with micro scale hydrodynamic cavitation may even cause the fracture of the kidney stones within a short time of 30 min. The proposed treatment method has proven to be an efficient instrument for destroying kidney stones. PMID:22476893

  8. Dimension stone

    USGS Publications Warehouse

    Dolley, T.P.

    2003-01-01

    Dimension stone can be defined as natural rock material quarried to obtain blocks or slabs that meet specifications as to size (width, length and thickness) and shape for architectural or engineering purposes. Color, grain texture and pattern, and surface finish of the stone are also normal requirements. Other important selection criteria are durability (based on mineral composition, hardness and past performance), strength and the ability of the stone to take a polish.

  9. Oxalate minerals on Mars?

    NASA Astrophysics Data System (ADS)

    Applin, D. M.; Izawa, M. R. M.; Cloutis, E. A.; Goltz, D.; Johnson, J. R.

    2015-06-01

    Small amounts of unidentified organic compounds have only recently been inferred on Mars despite strong reasons to expect significant concentrations and decades of searching. Based on X-ray diffraction and reflectance spectroscopic analyses we show that solid oxalic acid and its most common mineral salts are stable under the pressure and ultraviolet irradiation environment of the surface of Mars, and could represent a heretofore largely overlooked reservoir of organic carbon in the martian near-surface. In addition to the delivery to Mars by carbonaceous chondrites, oxalate minerals are among the predicted breakdown products of meteoritic organic matter delivered to the martian surface, as well as any endogenic organic carbon reaching the martian surface from the interior. A reinterpretation of pyrolysis experiments from the Viking, Phoenix, and Mars Science Laboratory missions shows that all are consistent with the presence of significant concentrations of oxalate minerals. Oxalate minerals could be important in numerous martian geochemical processes, including acting as a possible nitrogen sink (as ammonium oxalate), and contributing to the formation of organic carbonates, methane, and hydroxyl radicals.

  10. Kidney stone ablation times and peak saline temperatures during Holmium:YAG and Thulium fiber laser lithotripsy, in vitro, in a ureteral model

    NASA Astrophysics Data System (ADS)

    Hardy, Luke A.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

    2015-02-01

    Using a validated in vitro ureter model for laser lithotripsy, the performance of an experimental Thulium fiber laser (TFL) was studied and compared to clinical gold standard Holmium:YAG laser. The Holmium laser (? = 2120 nm) was operated with standard parameters of 600 mJ, 350 ?s, 6 Hz, and 270-?m-core optical fiber. TFL (? = 1908 nm) was operated with 35 mJ, 500 ?s, 150-500 Hz, and 100-?m-core fiber. Urinary stones (60% calcium oxalate monohydrate / 40% calcium phosphate), of uniform mass and diameter (4-5 mm) were laser ablated with fibers through a flexible video-ureteroscope under saline irrigation with flow rates of 22.7 ml/min and 13.7 ml/min for the TFL and Holmium laser, respectively. The temperature 3 mm from tube's center and 1 mm above mesh sieve was measured by a thermocouple and recorded during experiments. Total laser and operation times were recorded once all stone fragments passed through a 1.5-mm sieve. Holmium laser time measured 167 +/- 41 s (n = 12). TFL times measured 111 +/- 49 s, 39 +/- 11 s, and 23 +/- 4 s, for pulse rates of 150, 300, and 500 Hz (n = 12 each). Mean peak saline irrigation temperatures reached 24 +/- 1 C for Holmium, and 33 +/- 3 C, 33 +/- 7 C, and 39 +/- 6 C, for TFL at pulse rates of 150, 300, and 500 Hz. To avoid thermal buildup and provide a sufficient safety margin, TFL lithotripsy should be performed with pulse rates below 500 Hz and/or increased saline irrigation rates. The TFL rapidly fragmented kidney stones due in part to its high pulse rate, high power density, high average power, and reduced stone retropulsion, and may provide a clinical alternative to the conventional Holmium laser for lithotripsy.

  11. Optimum nutrition for kidney stone disease.

    PubMed

    Heilberg, Ita P; Goldfarb, David S

    2013-03-01

    We summarize the data regarding the associations of individual dietary components with kidney stones and the effects on 24-hour urinary profiles. The therapeutic recommendations for stone prevention that result from these studies are applied where possible to stones of specific composition. Idiopathic calcium oxalate stone-formers are advised to reduce ingestion of animal protein, oxalate, and sodium while maintaining intake of 800 to 1200 mg of calcium and increasing consumption of citrate and potassium. There are few data regarding dietary therapy of calcium phosphate stones. Whether the inhibitory effect of citrate sufficiently counteracts increasing urine pH to justify more intake of potassium and citrate is not clear. Reduction of sodium intake to decrease urinary calcium excretion would also be expected to decrease calcium phosphate stone recurrence. Conversely, the most important urine variable in the causation of uric acid stones is low urine pH, linked to insulin resistance as a component of obesity and the metabolic syndrome. The mainstay of therapy is weight loss and urinary alkalinization provided by a more vegetarian diet. Reduction in animal protein intake will reduce purine ingestion and uric acid excretion. For cystine stones, restriction of animal protein is associated with reduction in intake of the cystine precursor methionine as well as cystine. Reduction of urine sodium results in less urine cystine. Ingestion of vegetables high in organic anion content, such as citrate and malate, should be associated with higher urine pH and fewer stones because the amino acid cystine is soluble in more alkaline urine. Because of their infectious origin, diet has no definitive role for struvite stones except for avoiding urinary alkalinization, which may worsen their development. PMID:23439376

  12. Diet and renal stone formation.

    PubMed

    Trinchieri, A

    2013-02-01

    The relationship between diet and the formation of renal stones is demonstrated, but restrictive diets do not take into account the complexity of metabolism and the complex mechanisms that regulate the saturation and crystallization processes in the urine. The restriction of dietary calcium can reduce the urinary excretion of calcium but severe dietary restriction of calcium causes hyperoxaluria and a progressive loss of bone mineral component. Furthermore urinary calcium excretion is influenced by other nutrients than calcium as sodium, potassium, protein and refined carbohydrates. Up to 40% of the daily excretion of oxalate in the urine is from dietary source, but oxalate absorption in the intestine depends linearly on the concomitant dietary intake of calcium and is influenced by the bacterial degradation by several bacterial species of intestinal flora. A more rational approach should be based on the cumulative effects of foods and different dietary patterns on urinary saturation rather than on the effect of single nutrients. A diet based on a adequate intake of calcium (1000-1200 mg per day) and containment of animal protein and salt can decrease significantly urinary supersaturation for calcium oxalate and reduce the relative risk of stone recurrence in hypercalciuric renal stone formers. The DASH-style diet that is high in fruits and vegetables, moderate in low-fat dairy products and low in animal proteins and salt is associated with a lower relative supersaturation for calcium oxalate and a marked decrease in risk of incident stone formation. All the diets above mentioned have as a common characteristic the reduction of the potential acid load of the diet that can be correlated with a higher risk of recurrent nephrolithiasis, because the acid load of diet is inversely related to urinary citrate excretion. The restriction of protein and salt with an adequate calcium intake seem to be advisable but should be implemented with the advice to increase the intake of vegetables that can carry a plentiful supply of alkali that counteract the acid load coming from animal protein. New prospective studies to evaluate the effectiveness of the diet for the prevention of renal stones should be oriented to simple dietary advices that should be focused on a few specific goals easily controlled by means of self-evaluation tools, such as the LAKE food screener. PMID:23392537

  13. Cerium oxalate precipitation

    SciTech Connect

    Chang, T.P.

    1987-02-01

    Cerium, a nonradioactive, common stand-in for plutonium in development work, has been used to simulate several plutonium precipitation processes at the Savannah River Laboratory. There are similarities between the plutonium trifluoride and the cerium oxalate precipitations in particle size and extent of plating, but not particle morphology. The equilibrium solubility, precipitation kinetics, particle size, extent of plating, and dissolution characteristics of cerium oxalate have been investigated. Interpretations of particle size and plating based on precipitation kinetics (i.e., nucleation and crystal growth) are presented. 16 refs., 7 figs., 6 tabs.

  14. Determinants of Brushite Stone Formation: A Case-Control Study

    PubMed Central

    Siener, Roswitha; Netzer, Linda; Hesse, Albrecht

    2013-01-01

    Purpose The occurrence of brushite stones has increased during recent years. However, the pathogenic factors driving the development of brushite stones remain unclear. Methods Twenty-eight brushite stone formers and 28 age-, sex- and BMI-matched healthy individuals were enrolled in this case-control study. Anthropometric, clinical, 24 h urinary parameters and dietary intake from 7-day weighed food records were assessed. Results Pure brushite stones were present in 46% of patients, while calcium oxalate was the major secondary stone component. Urinary pH and oxalate excretion were significantly higher, whereas urinary citrate was lower in patients as compared to healthy controls. Despite lower dietary intake, urinary calcium excretion was significantly higher in brushite stone patients. Binary logistic regression analysis revealed pH>6.50 (OR 7.296; p?=?0.035), calcium>6.40 mmol/24 h (OR 25.213; p?=?0.001) and citrate excretion <2.600 mmol/24 h (OR 15.352; p?=?0.005) as urinary risk factors for brushite stone formation. A total of 56% of patients exhibited distal renal tubular acidosis (dRTA). Urinary pH, calcium and citrate excretion did not significantly differ between patients with or without dRTA. Conclusions Hypercalciuria, a diminished citrate excretion and an elevated pH turned out to be the major urinary determinants of brushite stone formation. Interestingly, urinary phosphate was not associated with urolithiasis. The increased urinary oxalate excretion, possibly due to decreased calcium intake, promotes the risk of mixed stone formation with calcium oxalate. Neither dietary factors nor dRTA can account as cause for hypercalciuria, higher urinary pH and diminished citrate excretion. Further research is needed to define the role of dRTA in brushite stone formation and to evaluate the hypothesis of an acquired acidification defect. PMID:24265740

  15. Stone chewing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Picking stones up into the mouth and chewing them has been commonly reported in pigs and also in dogs. It has variously been described as play behavior, redirected foraging behavior or a stereotypic behavior. In pigs, stone chewing is often observed in sows housed on paddocks, and most frequently o...

  16. Cholinergic signaling inhibits oxalate transport by human intestinal T84 cells

    PubMed Central

    Cheng, Ming; Aronson, Peter S.

    2012-01-01

    Urolithiasis remains a very common disease in Western countries. Seventy to eighty percent of kidney stones are composed of calcium oxalate, and minor changes in urinary oxalate affect stone risk. Intestinal oxalate secretion mediated by anion exchanger SLC26A6 plays a major constitutive role in limiting net absorption of ingested oxalate, thereby preventing hyperoxaluria and calcium oxalate urolithiasis. Using the relatively selective PKC-δ inhibitor rottlerin, we had previously found that PKC-δ activation inhibits Slc26a6 activity in mouse duodenal tissue. To identify a model system to study physiologic agonists upstream of PKC-δ, we characterized the human intestinal cell line T84. Knockdown studies demonstrated that endogenous SLC26A6 mediates most of the oxalate transport by T84 cells. Cholinergic stimulation with carbachol modulates intestinal ion transport through signaling pathways including PKC activation. We therefore examined whether carbachol affects oxalate transport in T84 cells. We found that carbachol significantly inhibited oxalate transport by T84 cells, an effect blocked by rottlerin. Carbachol also led to significant translocation of PKC-δ from the cytosol to the membrane of T84 cells. Using pharmacological inhibitors, we observed that carbachol inhibits oxalate transport through the M3 muscarinic receptor and phospholipase C. Utilizing the Src inhibitor PP2 and phosphorylation studies, we found that the observed regulation downstream of PKC-δ is partially mediated by c-Src. Biotinylation studies revealed that carbachol inhibits oxalate transport by reducing SLC26A6 surface expression. We conclude that carbachol negatively regulates oxalate transport by reducing SLC26A6 surface expression in T84 cells through signaling pathways including the M3 muscarinic receptor, phospholipase C, PKC-δ, and c-Src. PMID:21956166

  17. Crystallisation of calcium oxalate dihydrate in normal urine in presence of sodium copper chlorophyllin.

    PubMed

    Tawashi, R; Cousineau, M; Denis, G

    1982-01-01

    A method is described for the growth of calcium oxalate dihydrate in normal urine. Soluble chlorophyllin, at a concentration of 20 microgram/ml inhibited the crystallisation and the growth kinetics of the dihydrate crystals. The inhibitory capacity of chlorophyllin was compared with previous results. Data obtained suggest that the food and drug colourant chlorophyllin might be useful in the treatment of calcium oxalate stone disease. PMID:7179609

  18. Thorium oxalate solubility and morphology

    SciTech Connect

    Monson, P.R. Jr.; Hall, R.

    1981-10-01

    Thorium was used as a stand-in for studying the solubility and precipitation of neptunium and plutonium oxalates. Thorium oxalate solubility was determined over a range of 0.001 to 10.0 in the concentration parameter (H/sub 2/C/sub 2/O/sub 4/)/(HNO/sub 3/)/sup 2/. Morphology of thorium oxide made from the oxalate precipitates was characterized by scanning electron microscopy. The different morphologies found for oxalate-lean and oxalate-rich precipitations were in agreement with predictions based on precipitation theory.

  19. Alterations in macrophage cellular proteome induced by calcium oxalate crystals: the association of HSP90 and F-actin is important for phagosome formation.

    PubMed

    Singhto, Nilubon; Sintiprungrat, Kitisak; Thongboonkerd, Visith

    2013-08-01

    The presence of macrophages in renal interstitium is the key feature of progressive renal inflammation in kidney stone disease. However, response of macrophages to calcium oxalate monohydrate (COM) crystals, the major crystalline composition of kidney stone, remained unclear. This study aimed to investigate alterations in the cellular proteome of macrophages induced by COM crystals using a proteomics approach. U937-derived macrophages (by phorbol-12-myristate-13-acetate activation) were incubated without or with 100 ?g/mL COM crystals for 24 h. Their cellular proteins were resolved by 2-DE (n = 10 gels; 5 were derived from 5 independent cultures in each group) and visualized with Deep Purple fluorescent dye. Spot matching, quantitative intensity analysis, and statistics revealed 18 differentially expressed protein spots, which were successfully identified by Q-TOF MS and MS/MS analyses. The altered levels of ?-tubulin, ?-actin and ezrin were validated by Western blot analysis. Protein interaction network analysis using STRING software showed that 90 kDa heat shock protein (HSP90) was associated with ?-actin and ?-tubulin (all these three proteins were increased in the COM-treated macrophages). Multiple immunofluorescence stainings confirmed the associations of HSP90 with filamentous form of actin (F-actin) and ?-tubulin. However, only the association between HSP90 and F-actin was found on the phagosome membrane surrounding COM crystal, indicating that the association of HSP90 with F-actin, but not with ?-tubulin, is important for phagosome formation. Silencing of HSP90 (siHSP90) reduced expression of cytoskeletal proteins and phagosome marker (Rab5) and successfully diminished COM crystal-induced phagocytosis and migration of macrophages. Our findings enlightened the significant role of these altered proteins, especially HSP90, in enhanced phagocytic activity of the COM-exposed macrophages. PMID:23829382

  20. Adsorption characteristics of amino acids on to calcium oxalate.

    PubMed

    He, Junbin; Lin, Rihui; Long, Han; Liang, Yuwei; Chen, Yangyang

    2015-09-15

    Adsorption of amino acids on to calcium oxalate found in urinary calculus has been studied and the adsorption characteristics were analyzed. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were used to fit the kinetics data. The pseudo-second-order model best described the dynamic behavior of the adsorption process. The uptake of glutamic acid and aspartic acid were found to decrease as solution pH increasing from 4 to 8. The experimental data obtained at different pH conditions were analyzed and fitted by Langmuir, Freundlich, Redlich-Peterson, Temkin and Sips isotherm models using linear and nonlinear regression analysis. Error analysis (correlation coefficient, residual root mean square error and chi-square test) showed that the Langmuir I isotherm model and the non-linear form of Sips isotherm model should be primarily adopted for fitting the equilibrium data. The maximum adsorption capacity of glutamic acid and aspartic acid onto calcium oxalate monohydrate crystals are 0.059 and 0.066?mol/g at pH 4, respectively. These studies have the vital significance for research aimed at exploring the role of urinary amino acids effect the formation process of calcium oxalate crystals found in urinary calculus and for potential application in the design of synthetic peptides used for urinary calculi therapy. PMID:26021431

  1. Nutrition and renal stone disease in space

    NASA Technical Reports Server (NTRS)

    Zerwekh, Joseph E.

    2002-01-01

    There is a growing body of evidence from the National Aeronautics and Space Administration and the Russian space program showing that humans exposed to the microgravity environment of space have a greater risk for developing renal stones. Increased bone resorption and the attendant hypercalciuria and hyperphosphaturia contribute significantly to raising the urinary state of saturation with respect to the calcium salts, namely calcium oxalate and calcium phosphate. In addition, other environmental and dietary factors may adversely affect urine composition and increase stone formation risk during space flight. For example, reductions in urinary volume, pH, and citrate contribute to raising stone formation risk. In addition to raising the risk for calcium stone formation, this metabolic profile is conducive to the formation of uric acid stones. Although observations to date have suggested that there may actually be a reduced food intake during the early phase of flight, crew members on longer-duration flights may increase food intake and be at increased risk for stone formation. Taken together, these findings support the use of nutritional recommendations for crew members that would serve to reduce the stone-forming propensity of the urinary environment. Pharmacologic intervention should be directed at raising urinary volumes, diminishing bone losses, and preventing reductions in urinary pH and citrate. Success in reducing the risk for stone formation in astronauts would also be of potential major benefit to the estimated 20 million Americans with nephrolithiasis.

  2. Bariatric Surgery and Stone Disease

    NASA Astrophysics Data System (ADS)

    Lieske, John C.; Kumar, Rajiv

    2008-09-01

    Bariatric surgery is an effective treatment strategy for patients with morbid obesity that can result in effective weight loss, resolution of diabetes mellitus and other weight related complications, and even improved mortality. However, it also appears that hyperoxaluria is common after modern bariatric surgery, perhaps occurring in up to 50% of patients after Rouxen-Y gastric bypass. Although increasing numbers of patients are being seen with calcium oxalate kidney stones after bariatric surgery, and even a few with oxalosis and renal failure, the true risk of these outcomes remains unknown. The mechanisms that contribute to this enteric hyperoxaluria are also incompletely defined, although fat malabsorption may be an important component. Since increasing numbers of these procedures are likely to be performed in the coming years, further study regarding the prevalence and mechanisms of hyperoxaluria and kidney stones after bariatric surgery is needed to devise effective methods of treatment in order to prevent such complications.

  3. Establishment of a novel colorimetric assay for high-throughput analysis of calcium oxalate crystal growth modulation.

    PubMed

    Chutipongtanate, Somchai; Thongboonkerd, Visith

    2010-06-01

    Crystal growth is one of the most important mechanisms of calcium oxalate (CaOx) kidney stone formation. However, identification and characterization of CaOx crystal growth modulators were under-investigated in the past, probably due to the lack of an assay that could measure modulatory activities of a large number of candidates simultaneously. We therefore developed such a high-throughput assay based on colorimetric measurements of free calcium ions using Arsenazo III in a 96-well microplate, and a microplate reader (lambda620 nm). CaOx monohydrate (COM) was crystallized in the absence (blank control) or presence of 5 mM sodium citrate (Na(3)Citrate) (positive control) or 5 mM sodium chloride (NaCl) (negative control). The results showed that Na(3)Citrate, but not NaCl, could significantly inhibit COM crystal growth. The reliability of this novel assay was validated by quantitative analysis of COM crystal size. Degree of the inhibitory activity of Na(3)Citrate obtained from our novel assay was comparable to that obtained from the reference method (34.5 +/- 4.3 vs. 40.0 +/- 1.6%Inhibition, respectively; p was not significant). The high-throughput capability of the novel assay was demonstrated by simultaneous measurement of 33 samples (a triplicated set of 11 different concentrations of Na(3)Citrate) with linear correlation between Na(3)Citrate concentrations and COM crystal growth inhibitory activities (r = 0.893; p < 0.0001). In summary, we have successfully established a novel assay for high-throughput analysis of CaOx crystal growth modulatory activities of compounds that will be very useful for a large-scale analysis of CaOx crystal growth modulators. PMID:20498879

  4. Literature review for oxalate oxidation processes and plutonium oxalate solubility

    SciTech Connect

    Nash, C. A.

    2015-10-01

    A literature review of oxalate oxidation processes finds that manganese(II)-catalyzed nitric acid oxidation of oxalate in precipitate filtrate is a viable and well-documented process. The process has been operated on the large scale at Savannah River in the past, including oxidation of 20 tons of oxalic acid in F-Canyon. Research data under a variety of conditions show the process to be robust. This process is recommended for oxalate destruction in H-Canyon in the upcoming program to produce feed for the MOX facility. Prevention of plutonium oxalate precipitation in filtrate can be achieved by concentrated nitric acid/ferric nitrate sequestration of oxalate. Organic complexants do not appear practical to sequester plutonium. Testing is proposed to confirm the literature and calculation findings of this review at projected operating conditions for the upcoming campaign.

  5. The preventive effect of sodium pentosan polysulfate against renal stone formation in hyperoxaluric rats.

    PubMed

    Nakatani, Tatsuya; Ishii, Keiichi; Yoneda, Yukio; Kamikawa, Sadanori; Kanazawa, Toshinao; Sugimoto, Toshikado; Osswald, Hartmut

    2002-10-01

    Sodium pentosan polysulfate (SPP), a semi-synthetic glycosaminoglycan, was administered to rats with hyperoxaluria, induced by a vitamin B6 deficient diet, as a model of calcium oxalate stone formation. We studied the preventive effects of SPP on stone formation as well as its inhibitory effects on stone growth by autoradiography and radioluminography after intravenous injection of (14)C-oxalate. The rats were divided into non-treated and SPP-treated groups. The non-treated rats were divided into three groups: one group was fed a regular diet, while the other two groups were fed a vitamin B6 deficient diet for 2 and 4 weeks, respectively. The SPP-treated rats were divided into two groups: one group was intravenously injected with SPP from the start of the vitamin B6 deficient diet for a total of 4 weeks and the other group was injected with the same amount of SPP after 2 weeks of the diet for 2 weeks. (14)C-oxalate renal macroautoradiograms were prepared, and calcium oxalate deposits in the renal tissues were compared between the non-treated and SPP-treated groups. The preventive effects on calcium oxalate stone formation were clearly observed in the group injected with SPP for 4 weeks. Even in the other SPP-treated group, in which the administration of SPP was started at 2 weeks after the start of the diet when calcium oxalate stone formation was already observed, the size of the calcium oxalate deposits observed after 4 weeks was smaller than that in the non-treated group fed a vitamin B6 deficient diet for 4 weeks. In conclusion, our results show that SPP has not only preventive effects on calcium oxalate stone formation but also growth inhibitory effects on stones in hyperoxaluric rats. PMID:12389123

  6. Absorption kinetics of oxalate from oxalate-rich food in man

    SciTech Connect

    Prenen, J.A.; Boer, P.; Dorhout Mees, E.J.

    1984-11-01

    The absorption of oxalate was investigated in a healthy subject after ingestion of oxalate-rich meals (spinach and rhubarb) with and without addition of /sup 14/C-labeled oxalic acid and calcium oxalate, and after oxalate-free meals with addition of nonlabeled sodium oxalate and calcium oxalate. Under these conditions, calcium oxalate was absorbed to the same extent as soluble oxalate; only a small percentage (2.4 +/- 0.7) of the total oxalate load was absorbed. Significant oxalate absorption occurred within 1 to 8 h after ingestion. The results suggest that under normal conditions the proximal part of the small bowel is a major absorption site.

  7. Reactive oxygen species, inflammation and calcium oxalate nephrolithiasis.

    PubMed

    Khan, Saeed R

    2014-09-01

    Calcium oxalate (CaOx) kidney stones are formed attached to Randall's plaques (RPs) or Randall's plugs. Mechanisms involved in the formation and growth are poorly understood. It is our hypothesis that stone formation is a form of pathological biomineralization or ectopic calcification. Pathological calcification and plaque formation in the body is triggered by reactive oxygen species (ROS) and the development of oxidative stress (OS). This review explores clinical and experimental data in support of ROS involvement in the formation of CaOx kidney stones. Under normal conditions the production of ROS is tightly controlled, increasing when and where needed. Results of clinical and experimental studies show that renal epithelial exposure to high oxalate and crystals of CaOx/calcium phosphate (CaP) generates excess ROS, causing injury and inflammation. Major markers of OS and inflammation are detectable in urine of stone patients as well as rats with experimentally induced CaOx nephrolithiasis. Antioxidant treatments reduce crystal and oxalate induced injury in tissue culture and animal models. Significantly lower serum levels of antioxidants, alpha-carotene, beta-carotene and beta-cryptoxanthine have been found in individuals with a history of kidney stones. A diet rich in antioxidants has been shown to reduce stone episodes. ROS regulate crystal formation, growth and retention through the timely production of crystallization modulators. In the presence of abnormal calcium, citrate, oxalate, and/or phosphate, however, there is an overproduction of ROS and a decrease in the antioxidant capacity resulting in OS, renal injury and inflammation. Cellular degradation products in the urine promote crystallization in the tubular lumen at a faster rate thus blocking the tubule and plugging the tubular openings at the papillary tips forming Randall's plugs. Renal epithelial cells lining the loops of Henle/collecting ducts may become osteogenic, producing membrane vesicles at the basal side. In addition endothelial cells lining the blood vessels may also become osteogenic producing membrane vesicles. Calcification of the vesicles gives rise to RPs. The growth of the RP's is sustained by mineralization of collagen laid down as result of inflammation and fibrosis. PMID:25383321

  8. Reactive oxygen species, inflammation and calcium oxalate nephrolithiasis

    PubMed Central

    2014-01-01

    Calcium oxalate (CaOx) kidney stones are formed attached to Randall’s plaques (RPs) or Randall’s plugs. Mechanisms involved in the formation and growth are poorly understood. It is our hypothesis that stone formation is a form of pathological biomineralization or ectopic calcification. Pathological calcification and plaque formation in the body is triggered by reactive oxygen species (ROS) and the development of oxidative stress (OS). This review explores clinical and experimental data in support of ROS involvement in the formation of CaOx kidney stones. Under normal conditions the production of ROS is tightly controlled, increasing when and where needed. Results of clinical and experimental studies show that renal epithelial exposure to high oxalate and crystals of CaOx/calcium phosphate (CaP) generates excess ROS, causing injury and inflammation. Major markers of OS and inflammation are detectable in urine of stone patients as well as rats with experimentally induced CaOx nephrolithiasis. Antioxidant treatments reduce crystal and oxalate induced injury in tissue culture and animal models. Significantly lower serum levels of antioxidants, alpha-carotene, beta-carotene and beta-cryptoxanthine have been found in individuals with a history of kidney stones. A diet rich in antioxidants has been shown to reduce stone episodes. ROS regulate crystal formation, growth and retention through the timely production of crystallization modulators. In the presence of abnormal calcium, citrate, oxalate, and/or phosphate, however, there is an overproduction of ROS and a decrease in the antioxidant capacity resulting in OS, renal injury and inflammation. Cellular degradation products in the urine promote crystallization in the tubular lumen at a faster rate thus blocking the tubule and plugging the tubular openings at the papillary tips forming Randall’s plugs. Renal epithelial cells lining the loops of Henle/collecting ducts may become osteogenic, producing membrane vesicles at the basal side. In addition endothelial cells lining the blood vessels may also become osteogenic producing membrane vesicles. Calcification of the vesicles gives rise to RPs. The growth of the RP’s is sustained by mineralization of collagen laid down as result of inflammation and fibrosis. PMID:25383321

  9. Selective Rac1 inhibition protects renal tubular epithelial cells from oxalate-induced NADPH oxidase-mediated oxidative cell injury

    PubMed Central

    Thamilselvan, Vijayalakshmi; Menon, Mani

    2013-01-01

    Oxalate-induced oxidative cell injury is one of the major mechanisms implicated in calcium oxalate nucleation, aggregation and growth of kidney stones. We previously demonstrated that oxalate-induced NADPH oxidase-derived free radicals play a significant role in renal injury. Since NADPH oxidase activation requires several regulatory proteins, the primary goal of this study was to characterize the role of Rac GTPase in oxalate-induced NADPH oxidase-mediated oxidative injury in renal epithelial cells. Our results show that oxalate significantly increased membrane translocation of Rac1 and NADPH oxidase activity of renal epithelial cells in a time-dependent manner. We found that NSC23766, a selective inhibitor of Rac1, blocked oxalate-induced membrane translocation of Rac1 and NADPH oxidase activity. In the absence of Rac1 inhibitor, oxalate exposure significantly increased hydrogen peroxide formation and LDH release in renal epithelial cells. In contrast, Rac1 inhibitor pretreatment, significantly decreased oxalate-induced hydrogen peroxide production and LDH release. Furthermore, PKC α and δ inhibitor, oxalate exposure did not increase Rac1 protein translocation, suggesting that PKC resides upstream from Rac1 in the pathway that regulates NADPH oxidase. In conclusion, our data demonstrate for the first time that Rac1-dependent activation of NADPH oxidase might be a crucial mechanism responsible for oxalate-induced oxidative renal cell injury. These findings suggest that Rac1 signaling plays a key role in oxalate-induced renal injury, and may serve as a potential therapeutic target to prevent calcium oxalate crystal deposition in stone formers and reduce recurrence. PMID:21814770

  10. Fasting Urinary Calcium-to-Creatinine and Oxalate-to-Creatinine Ratios in Dogs with Calcium Oxalate Urolithiasis and Breed-Matched Controls

    PubMed Central

    Furrow, E.; Patterson, E.E.; Armstrong, P.J.; Osborne, C.A.; Lulich, J.P.

    2015-01-01

    Background Hypercalciuria and hyperoxaluria are risk factors for calcium oxalate (CaOx) urolithiasis, but breed-specific reports of urinary metabolites and their relationship with stone status are lacking. Objective To compare urinary metabolites (calcium and oxalate) and blood ionized calcium (iCa) concentrations between CaOx stone formers and breed-matched stone-free controls for the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds. Animals Forty-seven Miniature Schnauzers (23 cases and 24 controls), 27 Bichons Frise (14 cases and 13 controls), and 15 Shih Tzus (7 cases and 8 controls). Methods Prospective study. Fasting spot urinary calcium-to-creatinine and oxalate-to-creatinine ratios (UCa/Cr and UOx/Cr, respectively) and blood iCa concentrations were measured and compared between cases and controls within and across breeds. Regression models were used to test the effect of patient and environmental factors on these variables. Results UCa/Cr was higher in cases than controls for each of the 3 breeds. In addition to stone status, being on a therapeutic food designed to prevent CaOx stone recurrence was associated with higher UCa/Cr. UOx/Cr did not differ between cases and controls for any of the breeds. Blood iCa was higher in cases than controls in the Miniature Schnauzer and Bichon Frise breeds and had a moderate correlation with UCa/Cr. Conclusions and Clinical Importance Hypercalciuria is associated with CaOx stone status in the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds. UOx/Cr did not correlate with stone status in these 3 breeds. These findings may influence breed-specific stone prevention recommendations. PMID:25581880

  11. LITERATURE REVIEW FOR OXALATE OXIDATION PROCESSES AND PLUTONIUM OXALATE SOLUBILITY

    SciTech Connect

    Nash, C.

    2012-02-03

    A literature review of oxalate oxidation processes finds that manganese(II)-catalyzed nitric acid oxidation of oxalate in precipitate filtrate is a viable and well-documented process. The process has been operated on the large scale at Savannah River in the past, including oxidation of 20 tons of oxalic acid in F-Canyon. Research data under a variety of conditions show the process to be robust. This process is recommended for oxalate destruction in H-Canyon in the upcoming program to produce feed for the MOX facility. Prevention of plutonium oxalate precipitation in filtrate can be achieved by concentrated nitric acid/ferric nitrate sequestration of oxalate. Organic complexants do not appear practical to sequester plutonium. Testing is proposed to confirm the literature and calculation findings of this review at projected operating conditions for the upcoming campaign. H Canyon plans to commence conversion of plutonium metal to low-fired plutonium oxide in 2012 for eventual use in the Mixed Oxide Fuel (MOX) Facility. The flowsheet includes sequential operations of metal dissolution, ion exchange, elution, oxalate precipitation, filtration, and calcination. All processes beyond dissolution will occur in HB-Line. The filtration step produces an aqueous filtrate that may have as much as 4 M nitric acid and 0.15 M oxalate. The oxalate needs to be removed from the stream to prevent possible downstream precipitation of residual plutonium when the solution is processed in H Canyon. In addition, sending the oxalate to the waste tank farm is undesirable. This report addresses the processing options for destroying the oxalate in existing H Canyon equipment.

  12. Introduction: Kidney Stone Research, Lessons From Human Studies

    NASA Astrophysics Data System (ADS)

    Coe, Fredric L.

    2007-04-01

    About 5% of American women and 12% of men will develop a kidney stone at some time in their life, the prevalence has been rising in both sexes. Approximately 80% of stones are composed of calcium oxalate, and calcium phosphate; 10% of struvite; 9% of uric acid; and the remaining 1% are composed of cystine or ammonium acid urate or are diagnosed as drug-related stone. Stones ultimately arise because of an unwanted phase change of these substances from liquid to solid state. In this introduction, I have outlined our current thinking of the possible mechanisms involved in stone formation based on our biopsy data collected from a series of human kidney stone formers. In addition, I have presented a set of questions as a means of focusing future research in this field.

  13. Bifidobacterium animalis subsp. lactis decreases urinary oxalate excretion in a mouse model of primary hyperoxaluria

    PubMed Central

    Whittamore, Jonathan M.; Hatch, Marguerite

    2015-01-01

    Hyperoxaluria significantly increases the risk of calcium oxalate kidney stone formation. Since several bacteria have been shown to metabolize oxalate in vitro, including probiotic bifidobacteria, we focused on the efficiency and possible mechanisms by which bifidobacteria can infuence oxalate handling in vivo, especially in the intestines, and compared these results with the reported effects of Oxalobacter formigenes. Bifidobacterium animalis subsp. lactis DSM 10140 and B. adolescentis ATCC 15703 were administered to wild-type (WT) mice and to mice defcient in the hepatic enzyme alanine-glyoxylate aminotransferase (Agxt−/−, a mouse model of Primary Hyperoxaluria) that were fed an oxalate-supplemented diet. The administration of B. animalis subsp. lactis led to a significant decrease in urinary oxalate excretion in WT and Agxt−/− mice when compared to treatment with B. adolescent-is. Detection of B. animalis subsp. lactis in feces revealed that 3 weeks after oral gavage with the bacteria 64 % of WT mice, but only 37 % of Agxt−/− mice were colonized. Examining intestinal oxalate fuxes showed there were no significant changes to net oxalate secretion in colonized animals and were therefore not associated with the changes in urinary oxalate excretion. These results indicate that colonization with B. animalis subsp. lactis decreased urinary oxalate excretion by degrading dietary oxalate thus limiting its absorption across the intestine but it did not promote enteric oxalate excretion as reported for O. formigenes. Preventive or therapeutic administration of B. animalis subsp. lactis appears to have some potential to beneficially infuence dietary hyperoxaluria in mice. PMID:25269440

  14. Economics of stone disease/treatment

    PubMed Central

    Strohmaier, Walter Ludwig

    2012-01-01

    Objectives Urolithiasis is a considerable economic burden for health systems, especially in industrialised countries where the incidence of stone disease has increased during the last few decades, and probably will further increase for several reasons. Methods The survey was based on investigations in collaboration with a German health insurance company and on a literature search (PubMed, and the authors collection of proceedings of urolithiasis conferences: The keywords included economics, cost, urolithiasis, nephrolithiasis, renal stone disease, metaphylaxis, recurrence) during 19992011. In all, 1221 articles were found but only those cited here were sufficient for the purpose of the study. Due to the nature of the subject it is not possible to give levels of evidence, as economic data on stone treatment cannot be obtained with randomised studies. Results The costs for the treatment and diagnosis of stones vary tremendously among different healthcare systems. Several calculation models showed that metaphylaxis is medically and economically effective when used rationally. Rational metaphylaxis is restricted to patients with a high risk of recurrence (brushite, uric acid, cystine and infected stones, patients with residual fragments after stone treatment and recurrent calcium oxalate stone formers). Conclusions For the groups identified, metaphylaxis is cost-effective in almost all healthcare systems, but the cost saved differs. The savings increase even more when adding the economic loss avoided from days off work due to treatment of recurrent stones. In most countries, stone frequency must exceed one stone per patient per year before medical therapy is more cost-effective than dietary measures. PMID:26558036

  15. INSIGHTS INTO OXALATE BIOSYNTHESIS: DEVELOPING STRATEGIES TO IMPROVE THE NUTRITIONAL QUALITY AND PRODUCTION OF PLANT FOODS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxalate is known to be produced in a vast number of organisms, from simple microbes to complex animals. In animals the accumulation of these crystals is often associated with the pathological condition of urinary stone formation. In contrast to animals, other organisms appear to benefit from the a...

  16. Metabolic syndrome: a multifaceted risk factor for kidney stones.

    PubMed

    Domingos, Fernando; Serra, Adelaide

    2014-10-01

    Kidney stones and metabolic syndrome (MetS) are common conditions in industrialized countries. There is growing evidence of associations between kidney stone disease and MetS or some of its components. The link between uric acid stones and MetS is well understood, but the link with calcium oxalate (CaOx) stones, the most common kidney stone composition, is more complex, and MetS is frequently overlooked as a risk factor for calcium nephrolithiasis. The physiopathological mechanisms of kidney stone disease in MetS are reviewed in this article. Uric acid stones are a consequence of the excessively acidic urine that results from insulin resistance. The pathophysiology of CaOx stones may include: increased excretion of lithogenesis promoters and decreased excretion of inhibitors; increased risk of Randall's plaque development; and inflammatory damage to renal epithelia by oxidative stress, as a consequence of the insulin-resistant milieu that characterizes MetS. The last mechanism contributes to the adhesion of CaOx crystals to subepithelial calcium deposits working as anchor sites where stones can grow. The predominant MetS features could determine the chemical composition of the stones in each patient. Kidney stones may be a renal manifestation of MetS and features of this syndrome should be looked for in patients with idiopathic nephrolithiasis. PMID:24708398

  17. OXALATE DEPOSITION ON ASBESTOS BODIES

    EPA Science Inventory

    The clinical and histopathologic findings in three patients with a deposition of calcium oxalate crystals on ferruginous bodies after occupational exposure to asbestos are provided. In addition, we test the hypothesis that this oxalate can be generated through a nonenzymatic o...

  18. KIDNEY STONES: AN UPDATE ON CURRENT PHARMACOLOGICAL MANAGEMENT AND FUTURE DIRECTIONS

    PubMed Central

    Xu, Hongshi; Zisman, Anna L.; Coe, Fredric L.; Worcester, Elaine M.

    2013-01-01

    Introduction Kidney stones are a common problem worldwide with substantial morbidities and economic costs. Medical therapy reduces stone recurrence significantly. Much progress has been made in the last several decades in improving therapy of stone disease. Areas covered 1) effect of medical expulsive therapy on spontaneous stone passage, 2) pharmacotherapy in the prevention of stone recurrence, 3) future directions in the treatment of kidney stone disease. Expert Opinion fluid intake to promote urine volume of at least 2.5L each day is essential to prevent stone formation. Dietary recommendations should be adjusted based on individual metabolic abnormalities. Properly dosed thiazide treatment is the standard therapy for calcium stone formers with idiopathic hypercalciuria. Potassium alkali therapy is considered for hypocitraturia, but caution should be taken to prevent potential risk of calcium phosphate stone formation. For absorptive hyperoxaluria, low oxalate diet and increased dietary calcium intake are recommended. Pyridoxine has been shown effective in some cases of primary hyperoxaluria type I. Allopurinol is used in calcium oxalate stone formers with hyperuricosuria. Treatment of cystine stones remains challenging. Tiopronin can be used if urinary alkalinization and adequate fluid intake are insufficient. For struvite stones, complete surgical removal coupled with appropriate antibiotic therapy is necessary. PMID:23438422

  19. Trace elements in urinary stones: a preliminary investigation in Fars province, Iran.

    PubMed

    Keshavarzi, Behnam; Yavarashayeri, Nasrin; Irani, Dariush; Moore, Farid; Zarasvandi, Alireza; Salari, Mehrdad

    2015-04-01

    In view of the high incidence rate of urinary stones in the south and southwest of Iran, this paper investigates trace elements content including heavy metals in 39 urinary stones, collected from patients in Fars province, Iran. The mineralogy of the stones is investigated using X-ray diffractometry. The samples are classified into five mineral groups (calcium oxalate, uric acid, cystine, calcium phosphate and mixed stone). Major and trace elements in each group were determined using ICP-MS method. P and Ca constitute the main elements in urinary stones with Ca being more affine to oxalates while other alkali and alkaline earths precipitate with phosphate. Significant amounts of trace elements, especially Zn and Sr, were found in urinary calculi (calcium oxalate and phosphates) relative to biominerals (uric acid and cystine). Among urinary calculi, calcium phosphate contains greater amounts of trace metal than calcium oxalate. Phosphates seem to be the most important metal-bearing phases in urinary stones. Results indicate that concentrations of elements in urinary stones depend on the type of mineral phases. Significant differences in elements content across various mineralogical groups were found by applying statistical methods. Kruskal-Wallis test reveals significant difference between Ca, P, K, Na, Mg, S, Zn, Sr, Se, Cd, and Co content in different investigated mineral groups. Moreover, Mann-Whitney test differentiates Ca, Na, Zn, Sr, Co, and Ni between minerals in oxalate and uric acid stones. This study shows that urinary stone can provide complementary information on human exposure to elements and estimate the environmental risks involved in urinary stones formation. PMID:25433503

  20. Two cyclohexanespiro-5'-hydantoin monohydrates.

    PubMed

    Gauthier, T J; Yokum, T S; Morales, G A; McLaughlin, M L; Liu, Y H; Fronczek, F R

    1997-11-15

    Cyclohexanespiro-5'-hydantoin monohydrate, C8H12N2O2.H2O, has a chair-shaped cyclohexane ring with endocyclic torsion-angle magnitudes in the range 54.4 (2)-56.3 (2) degrees. All potential hydrogen-bond donors are involved in intermolecular hydrogen bonding, with lengths in the range 2.760 (2)-2.908 (2) A. In its indolyl adduct, 2-(3-indolyl)cyclohexanespiro-5'-hydantoin monohydrate, C16H17N3O2.H2O, the cyclohexane moiety adopts a chair conformation with the indolyl substituent in an equatorial position. The N-H portion of the hydantoin ring is cis to indolyl, while the C=O of the hydantoin is trans. Endocyclic torsion-angle magnitudes of the cyclohexane ring are in the range 54.2 (2)-56.7 (2) degrees. All potential hydrogen-bond donors are involved in intermolecular hydrogen bonds, with lengths 2.828 (2)-3.187 (2) A. PMID:9396146

  1. Prophylactic and therapeutic properties of a sodium citrate preparation in the management of calcium oxalate urolithiasis: randomized, placebo-controlled trial.

    PubMed

    Allie-Hamdulay, Shameez; Rodgers, Allen L

    2005-05-01

    The purpose of this study was to investigate the prophylactic and therapeutic effects of a hitherto untested preparation containing sodium citrate in the management of calcium oxalate urolithiasis. In this study, a host of calcium oxalate kidney stone risk factors was investigated using a randomised, placebo controlled, "within-patient" clinical trial. The trial involved four groups of subjects: healthy male controls, healthy female controls , calcium oxalate stone-forming males and calcium oxalate stone-forming females. There were 30 subjects in each group. Twenty subjects in each group ingested the preparation containing sodium citrate and ten subjects in each group ingested a placebo for 7 days. Collection of 24 h urines were carried out at baseline, at day 7 and day 10 (i.e. 3 days after suspension of drug/placebo ingestion). These were analysed for biochemical and physicochemical risk factors. They were also tested for their inhibitory properties in crystallization experiments. Data were statistically analyzed using analysis of variance (ANOVA). Key risk factors were significantly and beneficially altered across all groups after ingestion of the preparation. The pH and urinary citrate excretion increased while urinary oxalate and calcium excretions decreased, as did relative supersaturations of calcium oxalate and uric acid. In addition, inhibition of calcium oxalate crystallization increased. Beneficial carryover effects were observed for some risk factors. The results of this study have demonstrated, for the first time, that a sodium citrate-containing preparation favourably alters the risk factors for calcium oxalate urolithiasis. PMID:15871014

  2. Update on Oxalate Crystal Disease

    PubMed Central

    Lorenz, Elizabeth C.; Michet, Claude J.; Milliner, Dawn S.; Lieske, John C.

    2013-01-01

    Oxalate arthropathy is a rare cause of arthritis characterized by deposition of calcium oxalate crystals within synovial fluid. This condition typically occurs in patients with underlying primary or secondary hyperoxaluria. Primary hyperoxaluria constitutes a group of genetic disorders resulting in endogenous overproduction of oxalate, whereas secondary hyperoxaluria results from gastrointestinal disorders associated with fat malabsorption and increased absorption of dietary oxalate. In both conditions oxalate crystals can deposit in the kidney leading to renal failure. Since oxalate is primarily renally eliminated, it accumulates throughout the body in renal failure, a state termed oxalosis. Affected organs can include bones, joints, heart, eyes and skin. Since patients can present with renal failure and oxalosis before the underlying diagnosis of hyperoxaluria has been made, it is important to consider hyperoxaluria in patients who present with unexplained soft tissue crystal deposition. The best treatment of oxalosis is prevention. If patients present with advanced disease, treatment of oxalate arthritis consists of symptom management and control of the underlying disease process. PMID:23666469

  3. Molecular mechanisms of control of formation of calcium oxalate

    SciTech Connect

    Sikes, C.S.; Wierzbicki, A.; Sallis, J.D.

    1995-11-01

    The design of inhibitors of crystallization is aided by an understanding of the binding of the inhibitors at the molecular level and the influence of the binding on crystal morphology. Binding of citrate and phosphocitrate to calcium oxalate monohydrate (COM) crystals has been studied using scanning electron microscopy and molecular modeling. The COM crystal lattice presents two distinct surfaces that are not only calcium-rich but also have oxalate groups that are perpendicular to the liquid interface. This offers the best possibility for interaction with incoming anionic groups of an inhibitor molecule, allowing the most effective coordination with calcium ions of the lattice surface. For example, conformation and binding energies of citrate and phosphocitrate at ({minus}1 0 1) and (0 1 0) surfaces of COM have been evaluated. The superior performance of phosphocitrate as an inhibitor of COM formation can be attributed to the more favorable coordination of its functional groups with calcium ions of the ({minus}1 0 1) and (0 1 0) surfaces. These concepts may be relevant to the design of new antiscalants.

  4. Raman spectroscopy study of calcium oxalate extracted from cacti stems.

    PubMed

    Frausto-Reyes, Claudio; Loza-Cornejo, Sofia; Terrazas, Teresa; Terrazas, Tania; Miranda-Beltrn, Mara de la Luz; Aparicio-Fernndez, Xchitl; Lpez-Macas, Brenda M; Morales-Martnez, Sandra E; Ortiz-Morales, Martn

    2014-01-01

    To find markers that distinguish the different Cactaceae species, by using near infrared Raman spectroscopy and scanning electron microscopy, we studied the occurrence, in the stem, of solid deposits in five Cactaceae species (Coryphantha clavata, Ferocactus latispinus, Opuntia ficus-indica, O. robusta, and O. strepthacantha) collected from their natural habitats from a region of Mxico. The deposits in the tissues usually occurred as spheroidal aggregates, druses, or prismatic crystals. From the Raman spectra, the crystals were identified either as calcium oxalate monohydrate (CaC2O4H2O) or calcium oxalate dihydrate (CaC2O42H2O). Opuntia species (subfamily Opuntioideae) showed the presence of CaC2O4H2O, and the deposition of CaC2O42H2O was present in C. clavata and F. latispinus (subfamily Cactoideae, Cacteae tribe). As a punctual technique, Raman spectroscopy seems to be a useful tool to identify crystal composition. In addition to allowing the analysis of crystal morphology, this spectroscopic technique can be used to identify Cactaceae species and their chemotaxonomy. PMID:25280368

  5. Oxalate-induced activation of PKC-α and -δ regulates NADPH oxidase-mediated oxidative injury in renal tubular epithelial cells

    PubMed Central

    Menon, Mani; Thamilselvan, Sivagnanam

    2009-01-01

    Oxalate-induced oxidative stress contributes to cell injury and promotes renal deposition of calcium oxalate crystals. However, we do not know how oxalate stimulates reactive oxygen species (ROS) in renal tubular epithelial cells. We investigated the signaling mechanism of oxalate-induced ROS formation in these cells and found that oxalate significantly increased membrane-associated protein kinase C (PKC) activity while at the same time lowering cytosolic PKC activity. Oxalate markedly translocated PKC-α and -δ from the cytosol to the cell membrane. Pretreatment of LLC-PK1 cells with specific inhibitors of PKC-α or -δ significantly blocked oxalate-induced generation of superoxide and hydrogen peroxide along with NADPH oxidase activity, LDH release, lipid hydroperoxide formation, and apoptosis. The PKC activator PMA mimicked oxalate's effect on oxidative stress in LLC-PK1 cells as well as cytosol-to-membrane translocation of PKC-α and -δ. Silencing of PKC-α expression by PKC-α-specific small interfering RNA significantly attenuated oxalate-induced cell injury by decreasing hydrogen peroxide generation and LDH release. We believe this is the first demonstration that PKC-α- and -δ-dependent activation of NADPH oxidase is one of the mechanisms responsible for oxalate-induced oxidative injury in renal tubular epithelial cells. The study suggests that the therapeutic approach might be considered toward attenuating oxalate-induced PKC signaling-mediated oxidative injury in recurrent stone formers. PMID:19692488

  6. Effect of Potassium Citrate on Calcium Phosphate Stones in a Model of Hypercalciuria.

    PubMed

    Krieger, Nancy S; Asplin, John R; Frick, Kevin K; Granja, Ignacio; Culbertson, Christopher D; Ng, Adeline; Grynpas, Marc D; Bushinsky, David A

    2015-12-01

    Potassium citrate is prescribed to decrease stone recurrence in patients with calcium nephrolithiasis. Citrate binds intestinal and urine calcium and increases urine pH. Citrate, metabolized to bicarbonate, should decrease calcium excretion by reducing bone resorption and increasing renal calcium reabsorption. However, citrate binding to intestinal calcium may increase absorption and renal excretion of both phosphate and oxalate. Thus, the effect of potassium citrate on urine calcium oxalate and calcium phosphate supersaturation and stone formation is complex and difficult to predict. To study the effects of potassium citrate on urine supersaturation and stone formation, we utilized 95th-generation inbred genetic hypercalciuric stone-forming rats. Rats were fed a fixed amount of a normal calcium (1.2%) diet supplemented with potassium citrate or potassium chloride (each 4 mmol/d) for 18 weeks. Urine was collected at 6, 12, and 18 weeks. At 18 weeks, stone formation was visualized by radiography. Urine citrate, phosphate, oxalate, and pH levels were higher and urine calcium level was lower in rats fed potassium citrate. Furthermore, calcium oxalate and calcium phosphate supersaturation were higher with potassium citrate; however, uric acid supersaturation was lower. Both groups had similar numbers of exclusively calcium phosphate stones. Thus, potassium citrate effectively raises urine citrate levels and lowers urine calcium levels; however, the increases in urine pH, oxalate, and phosphate levels lead to increased calcium oxalate and calcium phosphate supersaturation. Potassium citrate induces complex changes in urine chemistries and resultant supersaturation, which may not be beneficial in preventing calcium phosphate stone formation. PMID:25855777

  7. Kidney Stones (For Parents)

    MedlinePLUS

    ... can develop in the urinary tract . Also called calculi or nephrolithiasis, kidney stones form when salts and ... form a stone. Struvite stones: Also called staghorn calculi because they look like a stag's antlers, these ...

  8. Renal stone risk assessment during Space Shuttle flights

    NASA Technical Reports Server (NTRS)

    Whitson, P. A.; Pietrzyk, R. A.; Pak, C. Y.

    1997-01-01

    PURPOSE: The metabolic and environmental factors influencing renal stone formation before, during, and after Space Shuttle flights were assessed. We established the contributing roles of dietary factors in relationship to the urinary risk factors associated with renal stone formation. MATERIALS AND METHODS: 24-hr. urine samples were collected prior to, during space flight, and following landing. Urinary and dietary factors associated with renal stone formation were analyzed and the relative urinary supersaturation of calcium oxalate, calcium phosphate (brushite), sodium urate, struvite and uric acid were calculated. RESULTS: Urinary composition changed during flight to favor the crystallization of calcium-forming salts. Factors that contributed to increased potential for stone formation during space flight were significant reductions in urinary pH and increases in urinary calcium. Urinary output and citrate, a potent inhibitor of calcium-containing stones, were slightly reduced during space flight. Dietary intakes were significantly reduced for a number of variables, including fluid, energy, protein, potassium, phosphorus and magnesium. CONCLUSIONS: This is the first in-flight characterization of the renal stone forming potential in astronauts. With the examination of urinary components and nutritional factors, it was possible to determine the factors that contributed to increased risk or protected from risk. In spite of the protective components, the negative contributions to renal stone risk predominated and resulted in a urinary environment that favored the supersaturation of stone-forming salts. Dietary and pharmacologic therapies need to be assessed to minimize the potential for renal stone formation in astronauts during/after space flight.

  9. Are stone analysis results different with repeated sampling?

    PubMed Central

    Lee, Terence T. N.; Elkoushy, Mohamed A.; Andonian, Sero

    2014-01-01

    Introduction: We assessed differences in results of stone analyses on subsequent sampling. Methods: A retrospective review of patients with stone analyses at a tertiary stone centre between March 2006 and July 2012 was performed. All stones were analyzed at a centralized laboratory using infrared spectroscopy. Patients were grouped according to the first predominant stone type on record, as defined by the predominant stone component of at least 60%. Stone groups included calcium oxalate (CaOx), calcium phosphate (CaP), uric acid (UA), cystine, struvite, mixed CaOx-CaP and mixed CaOx-UA. All patients had a full metabolic stone workup. Results: Of the 303 patients with stone analyses, 118 (38.9%) patients had multiple stone analyses. The mean age was 53.4 15.1 years, and 87 (73.7%) were males. Of the 118, the initial stone analysis showed 43 CaOx, 38 CaP, 21 UA, 4 CaOx-CaP, 2 CaOx-UA, 6 cystine, and 4 struvite. There was a different stone composition in 25 (21.2%) patients with a median time delay of 64.5 days. Different compositions were found in 7 CaOx (to 3 CaP, 2 CaOx-CaP, and 2 UA), 5 CaP (to 3 CaOx and 2 CaOx-CaP), 3 UA (to 3 CaOx), 4 CaOx-CaP (to 2CaOx, 1 UA and 1 CaP), 2 CaOx-UA (to 2 CaOx) and 4 struvite (to 3 CaP and 1 UA). Conclusions: Stone composition was different in 21.2% of patients on subsequent analyses. PMID:24940457

  10. Effect of dentin pretreatment with potassium oxalate: analysis of microtensile bond strengths and morphologic aspects.

    PubMed

    De Moraes Porto, Isabel Cristina Celerino; De Andrade, Ana Karina Maciel; Alves, Luiz Carlos; Braz, Rodivan

    2012-02-01

    An effective and stable bond is the most desirable characteristic of contemporary adhesive systems. The aim of this study was to evaluate the effect of potassium oxalate on dentin/resin bond strength. Dentin on the occlusal surface of human premolars was exposed and etched with 35% phosphoric acid, to receive 3% monohydrated potassium oxalate and the following adhesive systems: Scotchbond Multipurpose (SMO; 3M/ESPE) and Prime & Bond NT (PBO; Dentsply), followed by the application of resin composite (Z250; 3M/ESPE). The control groups (SM and PB) did not receive potassium oxalate application. The prepared teeth were kept in distilled water at 37C for 24 h and 12 months. They were then cut longitudinally into sticks with a bond area of ?0.8 mm(2) for submission to the microtensile bond strength test. The data were analyzed by two-factor ANOVA, Tamhane's paired comparisons, and the Student t-test (? = 0.05). The hybrid layer formed was observed by scanning electron microscopy (SEM). SEM analysis of the surfaces treated with PB revealed shorter resin tags associated with the application of potassium oxalate, whereas SM showed tags similar to those without potassium oxalate. A significant difference was shown between the two storage times for each of the protocols. There was a significant difference among SMO, SM, and PBO (24 h), as well as among SM, SMO, and PBO, and between PB and PBO (12 months). The application of potassium oxalate before conventional adhesive systems may result in alteration of the bond strength between dentin and resin composite, depending on the material. PMID:21809415

  11. Spectroscopic study of the inhibition of calcium oxalate calculi by Larrea tridentata

    NASA Astrophysics Data System (ADS)

    Pinales, Luis Alonso

    The causes of urolithiasis include such influences as diet, metabolic disorders, and genetic factors which have been documented as sources that aggravate urinary calculi depositions and aggregations, and, implicitly, as causes of urolithiasis. This study endeavors to detail the scientific mechanisms involved in calcium oxalate calculi formation, and, more importantly, their inhibition under growth conditions imposed by the traditional medicinal approach using the herbal extract, Larrea tridentata. The calculi were synthesized without and with Larrea tridentata infusion by employing the single diffusion gel technique. A visible decrease in calcium oxalate crystal growth with increasing amounts of Larrea tridentata herbal infusion was observed in photomicrographs, as well as a color change from white-transparent for pure crystals to light orange-brown for crystals with inhibitor. Analysis of the samples, which includes Raman, infrared absorption, scanning electron microscopy (SEM), and X-ray powder diffraction (XRD) techniques, demonstrate an overall transition in morphology of the crystals from monohydrate without herbal extract to dihydrate with inhibitor. Furthermore, the resulting data from Raman and infrared absorption support the possibilities of the influences, in this complex process, of NDGA and its derivative compounds from Larrea tridentata, and of the bonding of the magnesium of the inhibitor with the oxalate ion on the surface of the calculi crystals. This assumption corroborates well with the micrographs obtained under higher magnification, which show that the separated small crystallites consist of darker brownish cores, which we attribute to the dominance of growth inhibition by NDGA, surrounded by light transparent thin shells, which possibly correspond to passivation of the crystals by magnesium oxalate. The SEM results reveal the transformation from the dominant monoclinic structure of the calcium oxalate crystals grown alone to the tetragonal dipyramidal crystal structure of the calcium oxalate crystals grown with Larrea tridentata. Comparison between XRD experimental and simulated data, besides corroborating with our previous results, show that each sample is a combination of different structures.

  12. 21 CFR 520.608 - Dicloxacillin sodium monohydrate capsules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dicloxacillin sodium monohydrate capsules. 520.608... Dicloxacillin sodium monohydrate capsules. (a) Specifications. Each capsule contains dicloxacillin sodium monohydrate equivalent to 50, 100, 200, or 500 milligrams of dicloxacillin. (b) Sponsor. See No. 000856...

  13. 21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium sulfachloropyrazine monohydrate. 556.625... Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A tolerance of zero is established for residues of sodium sulfachloropyrazine monohydrate in the...

  14. 21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium sulfachloropyrazine monohydrate. 556.625... Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A tolerance of zero is established for residues of sodium sulfachloropyrazine monohydrate in the...

  15. 21 CFR 520.608 - Dicloxacillin sodium monohydrate capsules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Dicloxacillin sodium monohydrate capsules. 520.608... Dicloxacillin sodium monohydrate capsules. (a) Specifications. Each capsule contains dicloxacillin sodium monohydrate equivalent to 50, 100, 200, or 500 milligrams of dicloxacillin. (b) Sponsor. See No. 000856...

  16. 21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium sulfachloropyrazine monohydrate. 556.625... Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A tolerance of zero is established for residues of sodium sulfachloropyrazine monohydrate in the...

  17. 21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium sulfachloropyrazine monohydrate. 556.625... Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A tolerance of zero is established for residues of sodium sulfachloropyrazine monohydrate in the...

  18. 21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium sulfachloropyrazine monohydrate. 556.625... Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A tolerance of zero is established for residues of sodium sulfachloropyrazine monohydrate in the...

  19. Stones in cats and dogs: What can be learnt from them?

    PubMed Central

    Syme, Harriet M.

    2012-01-01

    Objective To review the clinical features of stone disease in dogs and cats for a non-veterinary audience. Methods Relevant peer-reviewed scientific reports were reviewed. Results Lower urinary tract stones are more common in dogs and cats than they are in humans. In addition to struvite stones, calcium oxalate, urate and cystine stones are all commonly found in the bladder and the urethra. The genetic basis for stone disease in some breeds of dog has been elucidated. The small size of cats creates technical challenges when managing ureterolithiasis. Conclusions Naturally occurring stone disease in companion animals is a valuable area for further study. The structure of the canine genome might facilitate the identification of novel disease loci in breeds of dog predisposed to stone formation. PMID:26558031

  20. Treatment of renal calcium stone disease with the synthetic glycosaminoglycan pentosan polysulphate.

    PubMed

    Fellstrm, B; Backman, U; Danielson, B; Wikstrm, B

    1994-01-01

    Glycosaminoglycans (GAGs) are potent inhibitors of calcium oxalate growth and aggregation. The synthetic GAG pentosan polysulphate (PPS) was used in the treatment of patients with renal calcium stone disease. Altogether, 121 patients were included in an open trial over a 3-year-period. The average stone episode rate and the stone operation rate were no different during treatment and in the pretreatment period. Altogether 48% of the patients were entirely stone-free during follow-up, whereas 29/56 patients who continued to form stones reported smaller stones that were more easily passed. It is concluded that there may be a role for PPS in the treatment of recurrent renal calcium stone disease, but a controlled study may be needed. PMID:7516780

  1. Monohydrated Sulfates in Aurorae Chaos

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image of sulfate-containing deposits in Aurorae Chaos was taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) at 0653 UTC (2:53 a.m. EDT) on June 10, 2007, near 7.5 degrees south latitude, 327.25 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 40 meters (132 feet) across. The region covered is roughly 12 kilometers (7.5 miles) wide at its narrowest point.

    Aurorae Chaos lies east of the Valles Marineris canyon system. Its western edge extends toward Capri and Eos Chasmata, while its eastern edge connects with Aureum Chaos. Some 750 kilometers (466 miles) wide, Aurorae Chaos is most likely the result of collapsed surface material that settled when subsurface ice or water was released.

    The top panel in the montage above shows the location of the CRISM image on a mosaic taken by the Mars Odyssey spacecraft's Thermal Emission Imaging System (THEMIS). The CRISM data covers an area featuring several knobs of erosion-resistant material at one end of what appears to be a large teardrop shaped plateau. Similar plateaus occur throughout the interior of Valles Marineris, and they are formed of younger, typically layered rocks that post-date formation of the canyon system. Many of the deposits contain sulfate-rich layers, hinting at ancient saltwater.

    The center left image, an infrared false color image, reveals a swath of light-colored material draped over the knobs. The center right image unveils the mineralogical composition of the area, with yellow representing monohydrated sulfates (sulfates with one water molecule incorporated into each molecule of the mineral).

    The lower two images are renderings of data draped over topography with 5 times vertical exaggeration. These images provide a view of the topography and reveal how the monohydrated sulfate-containing deposits drape over the knobs and also an outcrop in lower-elevation parts of the plateau.

    CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter and the Mars Science Laboratory for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter.

  2. Renal Stone Risk During Space Flight

    NASA Technical Reports Server (NTRS)

    Whitson, Peggy A.; Pietrzyk, Robert A.; Sams, Clarence F.; Pak, Charles Y. C.; Jones, Jeffrey A.

    1999-01-01

    Space flight produces a number of metabolic and physiological changes in the crewmembers exposed to microgravity. Following launch, body fluid volumes, electrolyte levels, and bone and muscle undergo changes as the human body adapts to the weightless environment. Changes in the urinary chemical composition may lead to the potentially serious consequences of renal stone formation. Previous data collected immediately after space flight indicate changes in the urine chemistry favoring an increased risk of calcium oxalate and uric acid stone formation (n = 323). During short term Shuttle space flights, the changes observed include increased urinary calcium and decreased urine volume, pH and citrate resulting in a greater risk for calcium oxalate and brushite stone formation (n = 6). Results from long duration Shuttle/Mir missions (n = 9) followed a similar trend and demonstrated decreased fluid intake and urine volume and increased urinary calcium resulting in a urinary environment saturated with the calcium stone-forming salts. The increased risk occurs rapidly upon exposure to microgravity, continues throughout the space flight and following landing. Dietary factors, especially fluid intake, or pharmacologic intervention can significantly influence the urinary chemical composition. Increasing fluid intake to produce a daily urine output of 2 liters/day may allow the excess salts in the urine to remain in solution, crystals formation will not occur and a renal stone will not develop. Results from long duration crewmembers (n = 2) who had urine volumes greater than 2.5 L/day minimized their risk of renal stone formation. Also, comparisons of stone-forming risk in short duration crewmembers clearly identified greater risk in those who produced less than 2 liters of urine/day. However, hydration and increased urine output does not correct the underlying calcium excretion due to bone loss and only treats the symptoms and not the cause of the increased urinary salts. Dietary modification and promising pharmacologic treatments may also be used to reduce the potential risk for renal stone formation. Potassium citrate is being used clinically to increase the urinary inhibitor levels to minimize the development of crystals and the growth of renal stones. Bisphosphonates are a class of drugs recently shown to help in patients with osteoporosis by inhibiting the loss of bones in elderly patients. This drug could potentially prevent the bone loss observed in astronauts and thereby minimize the increase in urinary calcium and reduce the risk for renal stone development. Results of NASA's renal stone risk assessment program clearly indicate that exposure to microgravity changes the urinary chemical environment such that there is an increased risk for supersaturation of stone-forming salts, including calcium oxalaie and brushite. These studies have indicated specific avenues for development of countermeasures for the increased renal stone risk observed during and following space flight. Increased hydration and implementation of pharmacologic countermeasures should largely mitigate the in-flight risk of renal stones.

  3. Oxalate Content of Different Drinkable Dilutions of Tea Infusions after Different Brewing Times

    PubMed Central

    Lotfi Yagin, Neda; Mahdavi, Reza; Nikniaz, Zeinab

    2012-01-01

    Background: The aims of this study were to determine the effect of different brewing times and diluting on oxalate content of loose-packed black teas consumed in Tabriz, Iran. Methods: The oxalate content of black teas after brewing for 5, 10, 15, 30, 60 minutes was measured in triplicate by enzymatic assay. In order to attain the most acceptable dilution of tea infusions, tea samples which were brewed for 15, 30 and 60 minutes were diluted two (120 ml), three (80 ml) and four (60 ml) times respectively. Results: There was a stepwise increase in oxalate concentrations associated with increased brewing times (P< 0.001) with oxalate contents ranging from 4.4 mg/240 ml for the 5 min to 6.3 mg/240 ml for 60 min brewing times, respectively. There were significant differences between the mean oxalate content of different dilutions after brewing for 15, 30 and 60 minutes (P< 0.001). Conclusion: The oxalate content of Iranian consumed black tea after different brewing times and different dilution was below the recommended levels. Therefore, it seems that consumption of black tea several times per day would not pose significant health risk in kidney stone patients and susceptible individuals. PMID:24688937

  4. [Oxalobacter formigenes--characteristics and role in development of calcium oxalate urolithiasis].

    PubMed

    Torzewska, Agnieszka

    2013-01-01

    Microorganisms are one of the important factors for urinary calculi formation. While urease-positive bacteria and nanobacteria contribute to stone formation, Oxalobacter formigenes rods play a protective role against the development of urolithiasis. Proteus mirabilis alkaline environment of the urinary tract and cause crystallization mainly of struvite (magnesium ammonium phosphate). However, nanobacteria, due to the possibility of apatite deposition on the surface of their cells, have long been considered as an etiological factor of urinary calculi consisting of calcium phosphates. O. formigenes is an anaerobe using oxalate as the main source of carbon and energy and occurs as natural gastrointestinal microflora of humans and animals. These bacteria control the amount of oxalate excretion degrading oxalates and regulating their transport by intestinal epithelium. Lower colonization of the human colon by O. formigenes can cause increased oxalate excretion and lead to the development of oxalate urolithiasis. Due to the positive influence of O. formigenes, there is ongoing research into the use of this microorganism as a probiotic in the prophylaxis or treatment of hyperoxaluria, both secondary and primary. The results of these studies are very promising, but they still require continuation. Future studies focus on the exact characteristics of O. formigenes including their metabolism and the development of methods for applying as a therapeutic agent the bacteria or their enzymes degrading the oxalate. PMID:24379255

  5. Dual-energy computed tomography for the differentiation of uric acid stones: ex vivo performance evaluation.

    PubMed

    Stolzmann, Paul; Scheffel, Hans; Rentsch, Katharina; Schertler, Thomas; Frauenfelder, Thomas; Leschka, Sebastian; Sulser, Tullio; Marincek, Borut; Alkadhi, Hatem

    2008-08-01

    We assessed the potential of dual-energy computed tomography (CT) for the differentiation between uric acid (UA)-containing and non-UA-containing urinary stones. Forty urinary stones of 16 different compositions in two sizes (or=5 mm) were examined in an ex vivo model. Thirty stones consisted of pure calcium oxalate (whewellite or wheddellite), calcium phosphate (apatite, brushite, or vaterite), ammonium magnesium phosphate (struvite), UA, ammonium acid urate, ammonium phosphate, sodium hydrogen urate, or cystine, and ten stones were of mixed composition (UA-sodium hydrogen urate, whewellite-urate, wheddellite-urate, whewellite-brushite, or whewellite-brushite-struvite). Scans were performed using dual-source CT in a dual-energy mode with the tubes simultaneously operating at 80 and 140 kV. Two readers analysed the data with respect to stone attenuation at each energy level. The stones were classified as UA- or non-UA-containing using manual attenuation measurements and software analysis results. Sensitivity, specificity, PPV, and NPV were calculated using crystallographic stone analysis as the gold standard. Twenty-six out of 40 stones (65%) contained no UA; 14 stones (35%) contained UA. When compared with UA-containing stones, the differences in attenuation values at 80 and 140 kV were significantly (P<0.001) higher in stones containing no UA. The software automatically mapped 39/40 stones (98%). Only one (2%) 2 mm UA-stone was missed. The software correctly classified all detected stones as UA- or non-UA-containing. The attenuation values of the missed stone were manually plotted into the analysis sheet which allowed for the correct classification of the stone (containing UA). Therefore, the sensitivity, specificity, PPV, and NPV for the detection of UA-containing stones was 100%. Ex vivo experience indicates that differentiation between UA- and non-UA-containing stones can be accurately performed using dual-source dual-energy CT. PMID:18545993

  6. Phenotypic characterization of kidney stone formers by endoscopic and histological quantification of intra-renal calcification

    PubMed Central

    Linnes, Michael P.; Krambeck, Amy E.; Cornell, Lynn; Williams, James C.; BS, Mark Korinek; Bergstralh, Eric J.; Li, Xujian; Rule, Andrew D.; McCollough, Cynthia M.; Vrtiska, Terri J.; Lieske, John C.

    2013-01-01

    Interstitial Randalls plaques and collecting duct plugs are distinct forms of renal calcification thought to provide sites for stone retention within the kidney. Here we assessed kidney stone precursor lesions in a random cohort of stone formers undergoing percutaneous nephrolithotomy. Each accessible papilla was endoscopically mapped following stone removal. The percent papillary surface area covered by plaque and plug were digitally measured using image analysis software. Stone composition was determined by micro-computed tomography and infrared analysis. A representative papillary tip was biopsied. Twenty-four hour urine collections were used to measure supersaturation and crystal growth inhibition. The vast majority (99%) of stone formers had Randalls plaque on at least 1 papilla, while significant tubular plugging (over 1% of surface area) was present in about one-fifth of patients. Among calcium oxalate stone formers the amount of Randalls plaque correlated with higher urinary citrate levels. Tubular plugging correlated positively with pH and brushite supersaturation but negatively with citrate excretion. Lower urinary crystal growth inhibition predicted the presence of tubular plugging but not plaque. Thus, tubular plugging may be more common than previously recognized among patients with all types of stones, including some with idiopathic calcium oxalate stones. PMID:23698231

  7. Analysis of renal stones by capillary isotachophoresis.

    PubMed

    Jarolmov, Zde?ka; Lubal, P?emysl; Kanick, Viktor

    2012-08-30

    An analytical method for the determination of the composition of renal stones by capillary isotachophoresis with conductometric detection was developed. Using different leading/terminating electrolyte systems, the qualitative and quantitative analysis of organic compounds (urate, xanthate, oxalate) and inorganic ions (phosphate, Ca(2+), Mg(2+), Na(+), NH(4)(+)) species commonly present in mixed renal stones in three separate steps can be carried out with limits of detection about 10 ?mol/L. The developed method was validated by the analysis of real samples and can be used for urinary calculi classification. In addition, it was verified that this method can also be employed for the determination of the above mentioned analytes in some other samples (bones, teeth) concerning apatite biominerals (fluoro-, carbonate-, chloro-apatite). PMID:22939127

  8. Urinary metabolic phenotyping the slc26a6 (chloride-oxalate exchanger) null mouse model

    PubMed Central

    Garcia-Perez, Isabel; Villaseor, Alma; Wijeyesekera, Anisha; Posma, Joram M.; Stamler, Jeremiah; Aronson, Peter; Unwin, Robert; Barbas, Coral; Elliott, Paul; Nicholson, Jeremy; Holmes, Elaine

    2014-01-01

    The prevalence of renal stone disease is increasing, although it remains higher in men than in women when matched for age. While still somewhat controversial, several studies have reported an association between renal stone disease and hypertension, but this may be confounded by a shared link with obesity. However, independent of obesity, hyperoxaluria has been shown to be associated with hypertension in stone-formers and the most common type of renal stone is composed of calcium oxalate. The chloride-oxalate exchanger slc26a6 (also known as CFEX or PAT-1), located in the renal proximal tubule, was originally thought to have an important role in sodium homeostasis and thereby blood pressure control, but it has recently been shown to have a key function in oxalate balance by mediating oxalate secretion in the gut. We have applied two orthogonal analytical platforms (NMR spectroscopy and capillary-electrophoresis with UV detection) in parallel to characterize the urinary metabolic signatures related to the loss of the renal chloride-oxalate exchanger in slc26a6 null mice. Clear metabolic differentiation between the urinary profiles of the slc26a6 null and the wild type mice were observed using both methods, with the combination of NMR and CE-UV providing extensive coverage of the urinary metabolome. Key discriminating metabolites included oxalate, m-hydroxyphenylpropionylsulfate (m-HPPS), trimethylamine-N-oxide, glycolate and scyllo-inositol (higher in SLC26A6 null mice) and hippurate, taurine, trimethylamine, and citrate (lower in slc26a6 null mice). In addition to the reduced efficiency of anion transport, several of these metabolites (hippurate, m-HPPS, methylamines) reflect alteration in gut microbial co-metabolic activities. Gender-related metabotypes were also observed in both wild type and slc26a6 null groups. Other urinary chemicals that showed a gender-specific pattern included trimethylamine, trimethylamine-N-oxide, citrate, spermidine, guanidinoacetate, and 2-oxoisocaproate. The gender-dependent metabolic expression of the consequences of slc26a6 deletion might have relevance to the difference in prevalence of renal stone formation in men and women. The modification of the microbial metabolites is consistent with the fact that the slc26a6 transporter is found in a range of tissues, including the kidney and intestine, and provides further evidence for the long reach of the microbiota in physiological and pathological processes. PMID:22594923

  9. [EXPERIENCE OF USE OF BLEMAREN® IN THE TREATMENT OF PATIENTS IN URIC ACID AND CALCIUM OXALATE UROLITHIASIS].

    PubMed

    Konstantinova, O V; Yanenko, E K

    2015-01-01

    154 patients with urolithiasis were under outpatient observation for 2-8 years. Among them there were 76 women and 78 men aged 21-66 years, of which 46 patients with uric acid urolithiasis, and 88--with calcium oxalate urolithiasis. Treatment of patients was carried out systematically, depending on their condition. Indications for the application of Blemaren® included the presence of uric acid stones, uric acid and/or oxalate crystalluria. The duration of treatment was 6.1 months. The dosage of the drug varied from 6 to 18 g per day and was selected individually, depending on the purpose of the appointment of Blemaren®. Reduction of the urine pH to 6.2- 6.8-7.2 was the criterion for properly selected dose. To dissolve uric acid stones in the presence of hyperuricemia and/or hyperuricuria, Blemaren® was administered in combination with allopurinol at a dose of 0.1 g 3-4 times a day. Besides pharmacotherapy, treatment included diet therapy. It was found that the morning urine pH in urate urolithiasis is sustainable and has a range of 5.0-6.0, in 80.4% of cases--range of 5.0-5.5. In calcium oxalate urolithiasis this parameter is also stable and has a range of 5.0-6.7, in 82.9% of cases--range of 5.5-6.0. Optimal urine pH to eliminate uric acid and oxalate crystalluria in patients with uric acid and calcium oxalate urolithiasis is the interval of 6.2-6.4. It was shown that Blemaren® is a highly effective agent for treatment and prevention of uric acid and calcium oxalate crystalluria in calcium oxalate and uric acid urolithiasis. Further, its effectiveness in dissolving of uric acid stones in the absence of an infectious inflammatory process is 82.3%. PMID:26859932

  10. Modulation of Calcium Oxalate Crystallization by Proteins and Small Molecules Investigated by In Situ Atomic Force Microscopy

    NASA Astrophysics Data System (ADS)

    Qiu, R.; Orme, C.; Cody, A. M.; Wierzbicki, A.; Hoyer, J.; Nancollas, G.; de Yoreo, J.

    2002-12-01

    Understanding the physical mechanisms by which biological inhibitors control nucleation and growth of inorganic crystals is a major focus of biomineral research. Calcium oxalate monohydrate (COM), which plays a functional role in plant physiology, is also a source of pathogenesis in humans where it causes kidney stone disease. Although a great deal of research has been carried out on the modulation COM by proteins and small molecules, the basic mechanism has not yet been understood. However, because the proteins that play a role in COM growth have been identified and sequenced, COM provides an excellent model system for research into biomineral growth. In this study, in situ atomic force microscopy (AFM) was used to monitor the COM surface under controlled growth conditions both from pure solutions and those doped with citrate and osteopontin (OPN) in order to determine their effects on surface morphology and growth dynamics at the molecular level. As with other solution-grown crystals such as calcite, COM grows on complex dislocation hillocks. In pure solution, while growth on the (010) face is isotropic, hillocks on the (-101) face exhibit anisotropic step kinetics. Steps of [-10-1] and <120> orientation are clearly delineated with the [-10-1] being the fast growing direction. When citrate is added to the solution, both growth rate and morphology are drastically changed on (-101) face, especially along the [-10-1] direction. This results in isotropic disc-shaped hillocks a shape that is then reflected in the macroscopic growth habit. In contrast, no large growth changes were observed on the (010) facet. At the same time, molecular modeling predicts an excellent fit of the citrate ion into the (-101) plane and a poor fit to the (010) face. Here we propose a model that reconciles the step-specific interactions implied by the AFM results with the face-specific predictions of the calculations. Finally, we present the results of doping with aspartic acid as well as OPN, an aspartic acid rich protein and a powerful inhibitor of COM growth. The AFM results show that OPN, like citrate, inhibits growth on the (-101) face through a step pinning mechanism at concentrations in the nM range. The implications of the findings to the field of medicine will also be addressed. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract No. W-7405-ENG-48.

  11. [Studies on urolithiasis. The histochemistry of the kidney tissues and stones from patients with urolithiasis].

    PubMed

    Tsai, S

    1986-01-01

    In this study, 17 kidney tissue specimens and 29 renal stones were obtained from patients with urolithiasis. Control kidney specimens were dissected from 7 individuals not suffering from urolithiasis. The tissue specimens were fixed with 1% cetylpiridinium chloride (CPC) in 10% formalin (for 24 hours at room temperature). Then the kidney tissue specimens were embedded in paraffin and stained with hematoxylin-eosin for general observation as well as histochemically for demonstration of complex carbohydrates. Also, stone specimens were embedded in epon and thin sections made by the mineral polishing specimen preparation, and stained along with the kidney tissues. For identifying individual acidic and neutral carbohydrates, the enzyme digestion was performed for some tissue sections prior to histochemical staining. The stone-forming kidney tissues, normal kidney tissues and urinary stones (calcium oxalate, mixed, struvite) contained some glycosaminoglycans and neutral glycoproteins, but uric acid stones and cystine stones did not. The results of digestion with enzymes indicated that calcium oxalate stone-forming kidney tissue contains heparitin (heparan) sulfate; mixed stone-forming tissue contains sialic acid, hyaluronic acid, chondroitin sulfate A, B, C and heparitin (heparan) sulfate; struvite stone-forming tissue contains sialic acid, hyaluronic acid, chondroitin sulfate A, C and heparitin (heparan) sulfate; and cystine stone-forming tissue contains sialic acid, chondroitin sulfate A, C and heparitin (heparan) sulfate. The stone organic matrix is classified into the amorphous and stratiform types. The amorphous type matrix contains chondroitin sulfate A, B, C and heparitin (heparan) sulfate, and the stratiform type matrix also contains sialic acid and hyaluronic acid. The stone-forming kidney tissues, normal kidney tissues and stones (calcium oxalate, mixed, struvite) contain an appreciable amount of alpha-D-glucose, alpha-D-mannose and beta-D-galactose, but the uric acid stones and cystine stones do not contain sugar residues. Since the specific glycosaminoglycan composition differed for kidneys of different mineral content and stones of different morphological type, we believe that some glycosaminoglycans in kidneys and amorphous type matrix might play the role of a nucleating agent, and that a stratiform type matrix encourages stone enlargement. PMID:2938457

  12. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  13. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  14. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  15. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  16. 21 CFR 168.111 - Dextrose monohydrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Dextrose monohydrate. 168.111 Section 168.111 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION SWEETENERS AND TABLE SIRUPS Requirements for Specific Standardized Sweeteners...

  17. Renal Stone Risk During Space Flight: Assessment and Countermeasure Validation

    NASA Technical Reports Server (NTRS)

    Whitson, P. A.; Sams, C. F.; Jones, J. A.; Pietrzke, R. A.; Nelman-Gonzalez, M. A.; Hudson, E. K.

    2007-01-01

    NASA has focused its future on exploration class missions including the goal of returning to the moon and landing on Mars. With these objectives, humans will experience an extended exposure to the harsh environment of microgravity and the associated negative effects on all the physiological systems of the body. Exposure to microgravity affects human physiology and results in changes to the urinary chemical composition during and after space flight. These changes are associated with an increased risk of renal stone formation. The development of a renal stone would have health consequences for the crewmember and negatively impact the success of the mission. As of January 2007, 15 known symptomatic medical events consistent with urinary calculi have been experienced by 13 U.S. astronauts and Russian cosmonauts. Previous results from both MIR and Shuttle missions have demonstrated an increased risk for renal stone formation. These data have shown decreased urine volume, urinary pH and citrate levels and increased urinary calcium. Citrate, an important urinary inhibitor of calcium-containing renal stones binds with calcium in the urine, thereby reducing the amount of calcium available to form calcium oxalate stones. Urinary citrate also prevents calcium oxalate crystals from aggregating into larger crystals and into renal stones. In addition, citrate makes the urine less acidic which inhibits the development of uric acid stones. Potassium citrate supplementation has been successfully used to treat patients who have formed renal stones. The evaluation of potassium citrate as a countermeasure has been performed during the ISS Expeditions 3-6, 8, 11-13 and is currently in progress during the ISS Expedition 14 mission. Together with the assessment of stone risk and the evaluation of a countermeasure, this investigation provides an educational opportunity to all crewmembers. Individual urinary biochemical profiles are generated and the risk of stone formation is estimated. Increasing fluid intake is recommended to all crewmembers. These results can be used to lower the risk for stone formation through lifestyle, diet changes or therapeutic administration to minimize the risk for stone development. With human presence in microgravity a continuing presence and exploration class missions being planned, maintaining the health and welfare of all crewmembers is critical to the exploration of space.

  18. Kidney stone risk following Roux-en-Y gastric bypass surgery

    PubMed Central

    Gonzalez, Ricardo D.

    2014-01-01

    Since the first report in 2005, Roux-en-Y gastric bypass (RYGB) surgery has been linked to a variety of metabolic changes that alter kidney stone risk. The studies with the highest level of evidence, performed in non-stone forming patients before and after RYGB, cite a number of kidney stone risk factors, including a 25% increase in urinary oxalate, a 30% decrease in urinary citrate, and reduction in urine volume by half a liter. In addition to these, recent clinical and experimental studies have contributed to our understanding of the pathophysiology of stone disease in this unique population. This review summarizes the current RYGB urinary chemistry profiles and epidemiological studies, outlines known and theoretical mechanisms of hyperoxaluria and hypocitrituria, and provides some standard recommendations for reducing stone risk in RYGB stone formers as well as some novel ones, including correction of metabolic acidosis and use of probiotics. PMID:25473624

  19. [Kidney stone formation during space flight and long-term bed rest].

    PubMed

    Okada, Atsushi; Ichikawa, Jun; Tozawa, Keiichi

    2011-10-01

    Microgravity environment like space flight or a condition requiring long-term bed-rest increase bone resorption and decrease bone formation, inducing the rapid decrease of bone minerals to osteoporosis. Bone mineral loss increases urinary calcium excretion and the risk of urinary stone formation. To clarify the influence of the conditions on renal stone formation, a 90-day bed rest test was performed to analyze the mechanism of microgravity or bed rest-induced stone formation and prevention by bisphosphonate medication and bed-rest exercise. As the results, renal stone formation was observed in control and exercise groups and no stone was seen in the medication group. In the medication group, urinary calcium excretion and relative supersaturation of calcium oxalate were lower than in the control group throughout the bed-rest and recovery period. Bisphosphonate is useful for the prevention of renal stone formation during space flight and long-term bed-rest. PMID:21960236

  20. Changes in Renal Function and Blood Pressure in Patients with Stone Disease

    NASA Astrophysics Data System (ADS)

    Worcester, Elaine M.

    2007-04-01

    Stone disease is a rare cause of renal failure, but a history of kidney stones is associated with an increased risk for chronic kidney disease, particularly in overweight patients. Loss of renal function seems especially notable for patients with stones associated with cystinuria, hyperoxaluria, and renal tubular acidosis, in whom the renal pathology shows deposits of mineral obstructing inner medullary collecting ducts, often diffusely. However, even idiopathic calcium oxalate stone formers have a mild but significant decrease in renal function, compared to age, sex and weight-matched normals, and appear to lose renal function with age at a slightly faster rate than non-stone formers. There is also an increased incidence of hypertension among stone formers, although women are more likely to be affected than men.

  1. Kidney Stones in Adults

    MedlinePLUS

    ... people than in non-Hispanic black people and Mexican Americans. Overweight and obese people are more likely ... more struvite stones. Cystine stones result from a genetic disorder that causes cystine to leak through the ...

  2. Sulfate and thiosulfate inhibit oxalate transport via a dPrestin (Slc26a6)-dependent mechanism in an insect model of calcium oxalate nephrolithiasis.

    PubMed

    Landry, Greg M; Hirata, Taku; Anderson, Jacob B; Cabrero, Pablo; Gallo, Christopher J R; Dow, Julian A T; Romero, Michael F

    2016-01-15

    Nephrolithiasis is one of the most common urinary tract disorders, with the majority of kidney stones composed of calcium oxalate (CaOx). Given its prevalence (US occurrence 10%), it is still poorly understood, lacking progress in identifying new therapies because of its complex etiology. Drosophila melanogaster (fruitfly) is a recently developed model of CaOx nephrolithiasis. Effects of sulfate and thiosulfate on crystal formation were investigated using the Drosophila model, as well as electrophysiological effects on both Drosophila (Slc26a5/6; dPrestin) and mouse (mSlc26a6) oxalate transporters utilizing the Xenopus laevis oocyte heterologous expression system. Results indicate that both transport thiosulfate with a much higher affinity than sulfate Additionally, both compounds were effective at decreasing CaOx crystallization when added to the diet. However, these results were not observed when compounds were applied to Malpighian tubules ex vivo. Neither compound affected CaOx crystallization in dPrestin knockdown animals, indicating a role for principal cell-specific dPrestin in luminal oxalate transport. Furthermore, thiosulfate has a higher affinity for dPrestin and mSlc26a6 compared with oxalate These data indicate that thiosulfate's ability to act as a competitive inhibitor of oxalate via dPrestin, can explain the decrease in CaOx crystallization seen in the presence of thiosulfate, but not sulfate. Overall, our findings predict that thiosulfate or oxalate-mimics may be effective as therapeutic competitive inhibitors of CaOx crystallization. PMID:26538444

  3. Adaptable coordination of U(IV) in the 2D-(4,4) uranium oxalate network: From 8 to 10 coordinations in the uranium (IV) oxalate hydrates

    NASA Astrophysics Data System (ADS)

    Duvieubourg-Garela, L.; Vigier, N.; Abraham, F.; Grandjean, S.

    2008-08-01

    Crystals of uranium (IV) oxalate hydrates, U(C 2O 4) 26H 2O ( 1) and U(C 2O 4) 22H 2O ( 2), were obtained by hydrothermal methods using two different U(IV) precursors, U 3O 8 oxide and nitric U(IV) solution in presence of hydrazine to avoid oxidation of U(IV) into uranyl ion. Growth of crystals of solvated monohydrated uranium (IV) oxalate, U(C 2O 4) 2H 2O(dma) ( 3), dma=dimethylamine, was achieved by slow diffusion of U(IV) into a gel containing oxalate ions. The three structures are built on a bi-dimensional complex polymer of U(IV) atoms connected through bis-bidentate oxalate ions forming [U(C 2O 4)] 4 pseudo-squares. The flexibility of this supramolecular arrangement allows modifications of the coordination number of the U(IV) atom which, starting from 8 in 1 increases to 9 in 3 and, finally increases, to 10 in 2. The coordination polyhedron changes from a distorted cube, formed by eight oxygen atoms of four oxalate ions, in 1, to a mono-capped square anti-prism in 3 and, finally, to a di-capped square anti-prism in 2, resulting from rotation of the oxalate ions and addition of one and two water oxygen atoms in the coordination of U(IV). In 1, the space between the ?2[U(C 2O 4) 2] planar layers is occupied by non-coordinated water molecules; in 2, the space between the staggered ?2[U(C 2O 4) 22H 2O] layers is empty, finally in 3, the solvate molecules occupy the interlayer space between corrugated ?2[U(C 2O 4) 2H 2O] sheets. The thermal decomposition of U(C 2O 4) 26H 2O under air and argon atmospheres gives U 3O 8 and UO 2, respectively.

  4. [Formation of organic acids by fungi isolated from the surface of stone monuments].

    PubMed

    Sazanova, K V; Shchiparev, S M; Vlasov, D Iu

    2014-01-01

    Capacity of the fungi isolated from the surface of stone monuments for acid formation was studied in cultures under various carbon sources and cultivation conditions. The composition of organic nutrients was adjusted according to the results of investigation of the surface layers from the monuments in urban environment. The primary soil formed at the surface of the stone monuments under urban conditions was shown to contain a variety of carbon and nitrogen sources and is a rich substrate for fungal growth. Oxalic acid was produced by fungi grown on media with various concentrations of sugars, sugar alcohols, and organic acids. Malic, citric, fumaric, and succinic acids were identified only at elevated carbohydrate concentrations, mostly in liquid cultures. Oxalic acid was the dominant among the acids produced by Aspergillus niger at all experimental setups. Unlike A. niger, the relative content of oxalic acid produced by Penicillium citrinum decreased at high carbohydrate concentrations. PMID:25844464

  5. Treatment of the Infected Stone.

    PubMed

    Marien, Tracy; Miller, Nicole L

    2015-11-01

    Infected kidney stones refer to stones that form because of urinary tract infections with urease-producing bacteria, secondarily infected stones of any composition, or stones obstructing the urinary tract leading to pyelonephritis. The mainstay of treatment of infection stones is complete stone removal. Kidney stones that obstruct the urinary tract and cause obstructive pyelonephritis are also frequently referred to as infected stones. Obstructive pyelonephritis is a urologic emergency as it can result in sepsis and even death. Infection stones and obstructive stones causing pyelonephritis are different disease processes, and their workup and management are described separately. PMID:26475943

  6. Androgens Involvement in the Pathogenesis of Renal Stones Formation

    PubMed Central

    Naghii, Mohammad Reza; Babaei, Mnasour; Hedayati, Mehdi

    2014-01-01

    Objective The potential role for the gonadal steroids in the pathogenesis of urolithiasis, higher mean of plasma oxalate concentration and kidney calcium oxalate deposition influenced by androgens in men has been proposed. In this study, the serum levels of steroid hormones as a pathogenesis of this condition in male patients with active renal stone disease compared with controls was investigated. Methods Forty patients diagnosed with renal stones and hospitalized for further clinical treatments or referred to our office after ultrasonographic evaluations participated in the study. Forty six healthy subjects served as controls. Steroid sex hormones in the plasma samples including testosterone, free testosterone, dihydrotestosterone, estradiol, and sex hormone binding globulin were analyzed. Results A significant difference was observed between patients and the control subjects regarding serum testosterone, free testosterone, dihydrotestosterone, estradiol, and sex hormone binding globulin. Conclusions Based on the results, a higher androgens level was diagnosed in renal stone patients, indicating a possibility of a substantial pathogenic role of testosterone, free testosterone, and dihydrotestosterone involvement in the pathogenesis of renal stones formation. Therefore, data presentation and further investigation on the relation between male steroids and urolithiasis is of importance and should be considered in evaluation of the etiology of the disease. PMID:24695421

  7. Oxalic acid decreases calcium absorption in rats

    SciTech Connect

    Weaver, C.M.; Martin, B.R.; Ebner, J.S.; Krueger, C.A.

    1987-11-01

    Calcium absorption from salts and foods intrinsically labeled with /sup 45/Ca was determined in the rat model. Calcium bioavailability was nearly 10 times greater for low oxalate kale, CaCO/sub 3/ and CaCl/sub 2/ than from CaC/sub 2/O/sub 4/ (calcium oxalate) and spinach (high in oxalates). Extrinsic and intrinsic labeling techniques gave a similar assessment of calcium bioavailability from kale but not from spinach.

  8. Dehydration of cytosine monohydrate at physiological temperatures

    SciTech Connect

    Martel, P.; Powell, B.M.

    1983-01-01

    Neutron diffraction, thermogravimetric, and mass spectrographic measurements have been used to show that cytosine monohydrate loses its water of hydration at physiological temperatures (approx. = 37/sup 0/C) and converts to cytosine. The ''activation energy'' for the dehydration process has been determined from isothermal weight curves and is 27.1 +/- 0.6 kcal . mol/sup -1/. It is suggested that pyrimidine dehydration may be involved in structural changes in DNA.

  9. Alterations in renal stone risk factors after space flight

    NASA Technical Reports Server (NTRS)

    Whitson, P. A.; Pietrzyk, R. A.; Pak, C. Y.; Cintron, N. M.

    1993-01-01

    Exposure to the microgravity environment of space produces a number of physiological changes of metabolic and environmental origin that could increase the potential for renal stone formation. Metabolic, environmental and physicochemical factors that influence renal stone risk potential were examined in 24-hour urine samples from astronauts 10 days before launch and on landing day to provide an immediate postflight assessment of these factors. In addition, comparisons were made between male and female crewmembers, and between crewmembers on missions of less than 6 days and those on 6 to 10-day missions. Results suggest that immediately after space flight the risk of calcium oxalate and uric acid stone formation is increased as a result of metabolic (hypercalciuria, hypocitraturia, pH) and environmental (lower urine volume) derangements, some of which could reflect residual effects of having been exposed to microgravity.

  10. Alterations in renal stone risk factors after space flight.

    PubMed

    Whitson, P A; Pietrzyk, R A; Pak, C Y; Cintrn, N M

    1993-09-01

    Exposure to the microgravity environment of space produces a number of physiological changes of metabolic and environmental origin that could increase the potential for renal stone formation. Metabolic, environmental and physicochemical factors that influence renal stone risk potential were examined in 24-hour urine samples from astronauts 10 days before launch and on landing day to provide an immediate postflight assessment of these factors. In addition, comparisons were made between male and female crewmembers, and between crewmembers on missions of less than 6 days and those on 6 to 10-day missions. Results suggest that immediately after space flight the risk of calcium oxalate and uric acid stone formation is increased as a result of metabolic (hypercalciuria, hypocitraturia, pH) and environmental (lower urine volume) derangements, some of which could reflect residual effects of having been exposed to microgravity. PMID:8345588

  11. Proteome Dynamics of the Specialist Oxalate Degrader Oxalobacter formigenes

    PubMed Central

    Ellis, Melissa E; Mobley, James A; Holmes, Ross P; Knight, John

    2016-01-01

    Oxalobacter formigenes is a unique intestinal organism that relies on oxalate degradation to meet most of its energy and carbon needs. A lack of colonization is a risk factor for calcium oxalate kidney stone disease. The release of the genome sequence of O. formigenes has provided an opportunity to increase our understanding of the biology of O. formigenes. This study used mass spectrometry based shotgun proteomics to examine changes in protein levels associated with the transition of growth from log to stationary phase. Of the 1867 unique protein coding genes in the genome of O. formigenes strain OxCC13, 1822 proteins were detected, which is at the lower end of the range of 1500–7500 proteins found in free-living bacteria. From the protein datasets presented here it is clear that O. formigenes contains a repertoire of metabolic pathways expected of an intestinal microbe that permit it to survive and adapt to new environments. Although further experimental testing is needed to confirm the physiological and regulatory processes that mediate adaptation with nutrient shifts, the O. formigenes protein datasets presented here can be used as a reference for studying proteome dynamics under different conditions and have significant potential for hypothesis development. PMID:26924912

  12. In vitro anti-lithogenic activity of lime powder regimen (LPR) and the effect of LPR on urinary risk factors for kidney stone formation in healthy volunteers.

    PubMed

    Chariyavilaskul, Pajaree; Poungpairoj, Poonsin; Chaisawadi, Suchada; Boonla, Chanchai; Dissayabutra, Thasinas; Prapunwattana, Phisit; Tosukhowong, Piyaratana

    2015-04-01

    Hypocitraturia, hypokaliuria, and increased oxidative stress are common lithogenic risk factors found in nephrolithiasis patients, especially in Thailand. We previously developed lime powder regimen (LPR), and demonstrated that LPR delivered citraturic, alkalinizing, and antioxidative effects in kidney stone patients. In this study, in vitro anti-lithogenic activity, in vivo acute toxicity, and crossover-designed phase 1 trial (in 13 healthy volunteers) of LPR were investigated. LPR inhibited the growth of calcium oxalate monohydrate (COM) crystals in dose-dependent manner, and inhibited the intracellular production of reactive oxygen species (ROS) in COM-treated HK-2 cells. LPR did not significantly alter viability of HK-2 cells. No acute toxicity was detected in mice orally fed with LPR (10 g/kg). No adverse effect and complaint of LPR ingestion (5 g/dose) were observed in the tested volunteers. Plasma citrate was elevated at 30 min after LPR load, which was higher than the water load control. Plasma potassium was significantly elevated at 30 min after LPR load and remained high for 2 h, and at 2 h, it was significantly higher than the water load. Urinary citrate was significantly increased at 1 h after LPR load and remained high for 2 h, and at 2 h, it was significantly higher than the water load. Urinary potassium was significantly increased at 1 h after LPR load and remained high for 3 h, and its levels at 1, 2, and 3 h were significantly higher than the water load. Urinary total antioxidant status was significantly increased at 2 h after LPR load. In conclusion, LPR had an inhibitory effect on COM growth and exerted as antioxidant to attenuate ROS production in the COM-treated renal tubular cells. LPR provided citraturic, kaliuric, and antioxidative responses in healthy individuals without any adverse events. This suggests that LPR is well tolerated and safe for daily consumption. PMID:25588323

  13. Renal Stone Risk during Spaceflight: Assessment and Countermeasure Validation

    NASA Technical Reports Server (NTRS)

    Whitson, Peggy A.; Pietrzyk, Robert A.; Jones, Jeffery A.; Sams, Clarence F.; Hudson, Ed K.; Nelman-Gonzalez, Mayra

    2009-01-01

    NASA's Vision for Space Exploration centers on exploration class missions including the goals of returning to the moon and landing on Mars. One of NASA's objectives is to focus research on astronaut health and the development of countermeasures that will protect crewmembers during long duration voyages. Exposure to microgravity affects human physiology and results in changes in the urinary chemical composition favoring urinary supersaturation and an increased risk of stone formation. Nephrolithiasis is a multifactorial disease and development of a renal stone is significantly influenced by both dietary and environmental factors. Previous results from long duration Mir and short duration Shuttle missions have shown decreased urine volume, pH, and citrate levels and increased calcium. Citrate, an important inhibitor of calcium-containing stones, binds with urinary calcium reducing the amount of calcium available to form stones. Citrate inhibits renal stone recurrence by preventing crystal growth, aggregation, and nucleation and is one of the most common therapeutic agents used to prevent stone formation. Methods: Thirty long duration crewmembers (29 male, 1 female) participated in this study. 24-hour urines were collected and dietary monitoring was performed pre-, in-, and postflight. Crewmembers in the treatment group received two potassium citrate (KCIT) pills, 10 mEq/pill, ingested daily beginning 3 days before launch, all in-flight days and through 14 days postflight. Urinary biochemical and dietary analyses were completed. Results: KCIT treated subjects exhibited decreased urinary calcium excretion and maintained the levels of calcium oxalate supersaturation risk at their preflight levels. The increased urinary pH levels in these subjects reduced the risk of uric acid stones. Discussion: The current study investigated the use of potassium citrate as a countermeasure to minimize the risk of stone formation during ISS missions. Results suggest that supplementation with potassium citrate decreases the risk of stone formation during and immediately after spaceflight.

  14. Renal-Stone Risk Assessment During Space Shuttle Flights

    NASA Technical Reports Server (NTRS)

    Whitson, Peggy A.; Pietrzyk, Robert A.; Pak, Charles Y. C.

    1996-01-01

    The metabolic and environmental factors influencing renal stone formation before, during, and after Space Shuttle flights were assessed. We established the contributing roles of dietary factors in relationship to the urinary risk factors associated with renal stone formation. 24-hr urine samples were collected prior to, during space flight, and following landing. Urinary factors associated with renal stone formation were analyzed and the relative urinary supersaturation ratios of calcium oxalate, calcium phosphate (brushite), sodium urate, struvite and uric acid were calculated. Food and fluid consumption was recorded for a 48-hr period ending with the urine collection. Urinary composition changed during flight to favor the crystallization of stone-forming salts. Factors that contributed to increased potential for stone formation during space flight were significant reductions in urinary pH and increases in urinary calcium. Urinary output and citrate, a potent inhibitor of calcium-containing stones, were slightly reduced during space flight. Dietary intakes were significantly reduced for a number of variables, including fluid, energy, protein, potassium, phosphorus and magnesium. This is the first in-flight characterization of the renal stone forming potential in astronauts. With the examination of urinary components and nutritional factors, it was possible to determine the factors that contributed to increased risk or protected from risk. In spite of the protective components, the negative contributions to renal stone risk predominated and resulted in a urinary environment that favored the supersaturation of stone-forming salts. The importance of the hypercalciuria was noted since renal excretion was high relative to the intake.

  15. [TRANSURETHRAL URETEROLITHOTRIPSY FOR UPPER URINARY TRACT STONE IN SMALL CHILDREN WEIGHNING AROUND 10KG].

    PubMed

    Nishimura, Yoko; Moriya, Kimihiko; Mitsui, Takahiko; Kitta, Takeya; Kanno, Yukiko; Kon, Masafumi; Shinohara, Nobuo

    2015-10-01

    Management strategy for upper urinary tract calculi in small children is still a matter controversial. We report successful management of ureteral stone with transurethral ureterolithotripsy (TUL) in 2 boys weighing around 10 kg. Case 1: A 2-year-old boy (78 cm in height, 9.6 kg in weight), who received hydrocortisone and fludrocortisone for the treatment of 21-hydroxylase deficiency, was referred to our hospital with a right 9-mm lower ureteral stone. For TUL, a 7.5 Fr rigid cystoscope was introduced into the ureter directly after dilation of the ureteral orifice. By using Holmium:YAG laser for lithotripsy, complete stone evacuation was achieved. Stone analysis showed the composition of calcium phosphate and calcium oxalate. Case 2: A 1-year-old boy (80 cm in height, 10.5 kg in weight) with neurofibromatosis type 1 was referred to our hospital with a left 7.5-mm ureteral stone at the ureteropelvic junction. TUL was performed using a 4.5 F rigid ureteroscope and Holmium:YAG laser. No residual stone was identified. Stone analysis showed the composition of calcium oxalate. TUL is a safe and feasible option for small children, even in boys weighing approximately 10 kg. PMID:26717789

  16. Effects of acid-base variables and the role of carbonic anhydrase on oxalate secretion by the mouse intestine invitro

    PubMed Central

    Whittamore, Jonathan M; Frost, Susan C; Hatch, Marguerite

    2015-01-01

    Hyperoxaluria is a major risk factor for calcium oxalate kidney stones and the intestine is recognized as an important extra-renal pathway for eliminating oxalate. The membrane-bound chloride/bicarbonate (Cl?/) exchangers are involved in the transcellular movement of oxalate, but little is understood about how they might be regulated. , CO2, and pH are established modulators of intestinal NaCl cotransport, involving Na+/H+ and Cl?/ exchange, but their influence on oxalate transport is unknown. Measuring 14C-oxalate and 36Cl fluxes across isolated, short-circuited segments of the mouse distal ileum and distal colon we examined the role of these acid-base variables and carbonic anhydrase (CA) in oxalate and Cl? transport. In standard buffer both segments performed net oxalate secretion (and Cl? absorption), but only the colon, and the secretory pathway were responsive to and CO2. Ethoxzolamide abolished net oxalate secretion by the distal colon, and when used in tandem with an impermeant CA inhibitor, signaled an intracellular CA isozyme was required for secretion. There was a clear dependence on as their removal eliminated secretion, while at 42mmol/L was also decreased and eradicated. Independent of pH, raising Pco2 from 28 to 64 mmHg acutely stimulated net oxalate secretion 41%. In summary, oxalate secretion by the distal colon was dependent on , CA and specifically modulated by CO2, whereas the ileum was remarkably unresponsive. These findings highlight the distinct segmental heterogeneity along the intestine, providing new insights into the oxalate transport mechanism and how it might be regulated. PMID:25716924

  17. 21 CFR 520.608 - Dicloxacillin sodium monohydrate capsules.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Dicloxacillin sodium monohydrate capsules. 520.608 Section 520.608 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Dicloxacillin sodium monohydrate capsules. (a) Specifications. Each capsule contains dicloxacillin...

  18. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium sulfachloropyrazine monohydrate. 520.2184... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2184 Sodium sulfachloropyrazine monohydrate. (a) Chemical name. 2-Sulfamido-6-chloroxyrazine, sodium. (b) Sponsor. See Nos....

  19. 21 CFR 520.608 - Dicloxacillin sodium monohydrate capsules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Dicloxacillin sodium monohydrate capsules. 520.608 Section 520.608 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Dicloxacillin sodium monohydrate capsules. (a) Specifications. Each capsule contains dicloxacillin...

  20. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium sulfachloropyrazine monohydrate. 520.2184 Section 520.2184 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... sulfachloropyrazine monohydrate. (a) Chemical name. 2-Sulfamido-6-chloroxyrazine, sodium. (b) Sponsor. See Nos....

  1. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium sulfachloropyrazine monohydrate. 520.2184 Section 520.2184 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... sulfachloropyrazine monohydrate. (a) Chemical name. 2-Sulfamido-6-chloroxyrazine, sodium. (b) Sponsor. See Nos....

  2. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium sulfachloropyrazine monohydrate. 520.2184 Section 520.2184 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... sulfachloropyrazine monohydrate. (a) Chemical name. 2-Sulfamido-6-chloroxyrazine, sodium. (b) Sponsor. See Nos....

  3. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium sulfachloropyrazine monohydrate. 520.2184 Section 520.2184 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... sulfachloropyrazine monohydrate. (a) Chemical name. 2-Sulfamido-6-chloroxyrazine, sodium. (b) Sponsor. See Nos....

  4. Solubility, inhibition of crystallization and microscopic analysis of calcium oxalate crystals in the presence of fractions from Humulus lupulus L.

    NASA Astrophysics Data System (ADS)

    Fr?ckowiak, Anna; Ko?lecki, Tomasz; Skibi?ski, Przemys?aw; Gawe?, Wies?aw; Zaczy?ska, Ewa; Czarny, Anna; Piekarska, Katarzyna; Gancarz, Roman

    2010-11-01

    Procedures for obtaining noncytotoxic and nonmutagenic extracts from Humulus lupulus L. of high potency for inhibition and dissolving of model (calcium oxalate crystals) and real kidney stones, obtained from patients after surgery, are presented. Multistep extraction procedures were performed in order to obtain the preparations with the highest calcium complexing properties. The composition of obtained active fractions was analyzed by GC/MS and NMR methods. The influence of preparations on inhibition of formation and dissolution of model and real kidney stones were evaluated based on conductrometric titration, flame photometry and microscopic analysis. The "fraction soluble in methanol" obtained from water-alkaline extracts contains sugar alcohols and organic acids, and is effective in dissolving the kidney stones. The "fraction insoluble in methanol" contains only sugar derivatives and it changes the morphology of the crystals, making them "jelly-like". Both fractions are potentially effective in kidney stone therapy.

  5. Demographics and Characterization of 10,282 Randall Plaque-Related Kidney Stones

    PubMed Central

    Letavernier, Emmanuel; Vandermeersch, Sophie; Traxer, Olivier; Tligui, Mohamed; Baud, Laurent; Ronco, Pierre; Haymann, Jean-Philippe; Daudon, Michel

    2015-01-01

    Abstract Renal stone incidence has progressively increased in industrialized countries, but the implication of Randall plaque in this epidemic remains unknown. Our objectives were to determine whether the prevalence of Randall plaque-related stones increased during the past decades after having analyzed 30,149 intact stones containing mainly calcium oxalate since 1989 (cross-sectional study), and to identify determinants associated with Randall plaque-related stones in patients (casecontrol study). The proportion of Randall plaque-related stones was assessed over 3 time periods: 19891991, 19992001, and 20092011. Moreover, we analyzed clinical and biochemical parameters of 105 patients affected by calcium oxalate stones, with or without plaque. Of 30,149 calcium oxalate stones, 10,282 harbored Randall plaque residues (34.1%). The prevalence of Randall plaque-related stones increased dramatically during the past years. In young women, 17% of calcium oxalate stones were associated with Randall plaque during the 19891991 period, but the proportion rose to 59% 20 years later (P?stone-related event earlier in life as compared with those without plaque (median age 26 vs 34 years, P?=?0.02), had increased ionized serum calcium levels (P?=?0.04), and increased serum osteocalcin (P?=?0.001) but similar 25-hydroxyvitamin D levels. The logistic regression analysis showed that age (odds ratio [OR] 0.96, confidence interval [CI] 0.9260.994, P?=?0.02), weight (OR 0.97, CI 0.9340.997, P?=?0.03), and osteocalcin serum levels (OR 1.12, CI 1.0201.234, P?=?0.02) were independently associated with Randall plaque. The prevalence of the FokI f vitamin D receptor polymorphism was higher in patients with plaque (P?=?0.047). In conclusion, these findings point to an epidemic of Randall plaque-associated renal stones in young patients, and suggest a possible implication of altered vitamin D response. PMID:25761176

  6. Peanut-induced acute oxalate nephropathy with acute kidney injury

    PubMed Central

    Park, Hyeoncheol; Eom, Minseob; Won Yang, Jae; Geun Han, Byoung; Ok Choi, Seung; Kim, Jae Seok

    2014-01-01

    Oxalate nephropathy is commonly caused by ethylene glycol, vitamin C, and foods like star fruit that contain a lot of oxalate. Peanuts also have high oxalate contents. However, case reports of peanut-induced oxalate nephropathy are not common. Here, we describe a case of peanut-induced acute oxalate nephropathy with acute kidney injury and intend to demonstrate the conditions under which peanut-induced oxalate nephropathy is likely to occur. PMID:26877960

  7. Magnetic Properties of Dihydrate and Monohydrate Forms of Nickel Dibromide

    NASA Astrophysics Data System (ADS)

    Defotis, G. C.; Desanto, C. L.; Davis, C. M.; Pothen, J. M.; Hampton, A. S.

    2008-10-01

    As with transition metal bromides generally, especially hydrates, the title materials are either little studied previously or not at all (monohydrate). Curie-Weiss analysis of paramagnetic region susceptibilities yields Weiss theta values of 8.0 and 27.3 K for dihydrate and monohydrate respectively, indicating predominant ferromagnetic interactions but less so in the dihydrate. Peculiar behavior appears in the susceptibility of the monohydrate in the 40-100 K range. A large zero field splitting of the triplet ground state emerges from fits to dihydrate data especially. Susceptibility maxima occur just below and, unexpectedly, just above 6.0 K for dihydrate and monohydrate respectively. Fits to the data suggest more lower dimensional magnetic character in the monohydrate. While magnetization isotherms in the two systems are without hysteresis, a remarkable contrast in their temperature evolution distinguishes the two materials.

  8. Evaluation of sulfated polysaccharides from the brown seaweed Dictyopteris justii as antioxidant agents and as inhibitors of the formation of calcium oxalate crystals.

    PubMed

    Melo, Karoline Rachel Teodosio; Camara, Rafael Barros Gomes; Queiroz, Moacir Fernandes; Vidal, Arthur Anthunes Jacome; Lima, Camila Renata Machado; Melo-Silveira, Raniere Fagundes; Almeida-Lima, Jailma; Rocha, Hugo Alexandre Oliveira

    2013-01-01

    Oxalate crystals and other types of crystals are the cause of urolithiasis, and these are related to oxidative stress. The search for new compounds with antioxidant qualities and inhibitors of these crystal formations is therefore necessary. In this study, we extracted four sulfated polysaccharides, a fucoglucoxyloglucuronan (DJ-0.3v), a heterofucan (DJ-0.4v), and two glucans (DJ-0.5v and DJ-1.2v), from the marine alga Dictyopteris justii. The presence of sulfated polysaccharides was confirmed by chemical analysis and FT-IR. All the sulfated polysaccharides presented antioxidant activity under different conditions in some of the in vitro tests and inhibited the formation of calcium oxalate crystals. Fucan DJ-0.4v was the polysaccharide that showed the best antioxidant activity and was one of the best inhibitors of the crystallization of calcium oxalate. Glucan DJ-0.5v was the second most potent inhibitor of the formation of oxalate crystals, as it stabilized dehydrated oxalate crystals (less aggressive form), preventing them from transforming into monohydrate crystals (more aggressive form). The obtained data lead us to propose that these sulfated polysaccharides are promising agents for use in the treatment of urolithiasis. PMID:24287990

  9. Engineering calcium oxalate crystal formation in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many plants accumulate crystals of calcium oxalate. Just how these crystals form remains unknown. To gain insight into the mechanisms regulating calcium oxalate crystal formation, a crystal engineering approach was initiated utilizing the non-crystal accumulating plant, Arabidopsis. The success of t...

  10. Neptunium (IV) oxalate solubility. [22, 45, 60/sup 0/C

    SciTech Connect

    Luerkens, D W

    1983-07-01

    The equilibrium solubility of neptunium (IV) oxalate in nitric/oxalic acid solutions was determined at 22/sup 0/C, 45/sup 0/C, and 60/sup 0/C. The concentrations of nitric/oxalic acid solutions represented a wide range of free oxalate ion concentration. A mathematical solubility model was developed which is based on the formation of the known complexes of neptunium (IV) oxalate. the solubility model uses a simplified concentration parameter which is proportional to the free oxalate ion concentration. The solubility model can be used to estimate the equilibrium solubility of neptunium (IV) oxalate over a wide range of oxalic and nitric acid concentrations at each temperature.

  11. Managing caliceal stones

    PubMed Central

    Gross, Andreas J.; Knipper, Sophie; Netsch, Christopher

    2014-01-01

    The natural course of untreated asymptomatic caliceal calculi has not been clearly defined, especially in terms of disease progression, and the indications for and outcomes of surgical intervention are not precise. Caliceal stones may remain asymptomatic but, in case of migration, ureteral calculi can cause acute ureteric colic with severe complications. The decision for an active treatment of caliceal calculi is based on stone composition, stone size and symptoms. Extracorporal shock-wave lithotripsy (ESWL) has a low complication rate and is recommended by the current guidelines of the European Association of Urology as a first-line therapy for the treatment of caliceal stones <2 cm in diameter. However, immediate stone removal is not achieved with ESWL. The primary stone-free rates (SFR) after ESWL depend on stone site and composition and, especially for lower pole calculi, the SFR differ widely from other caliceal stones. Minimally-invasive procedures including percutaneous nephrolithotomy and ureteroscopy are alternatives for the treatment of caliceal stones, associated with low morbidity and high primary SFR when performed in centers of excellence. PMID:24497690

  12. Biogenesis of Oxalate in Plant Tissues

    PubMed Central

    Chang, Chi-Cheng; Beevers, Harry

    1968-01-01

    Red beet root discs aerated in potassium phosphate for 2 to 3 days and young spinach leaves actively produce oxalate. A series of labeled compounds was supplied to each of these tissues to determine the extent of conversion to oxalate. Similar results were obtained with the 2 tissues except that in the leaf tissue glyoxylate and glycolate were outstandingly good precursors. Carbon from glucose, acetate, and particularly from some acids of the tricarboxylic acid cycle was recovered in oxalate. Extracts from both tissues were found to contain an enzyme which converts oxaloacetate to oxalate and acetate. The enzyme was partially purified and some of its properties are described. A pathway of oxalate synthesis which does not include glycolate or its oxidase is therefore proposed. PMID:16656975

  13. Effects of pyruvate salts, pyruvic acid, and bicarbonate salts in preventing experimental oxalate urolithiasis in rats.

    PubMed

    Ogawa, Y; Yamaguchi, K; Tanaka, T; Morozumi, M

    1986-05-01

    Sodium pyruvate, potassium pyruvate, pyruvic acid, sodium bicarbonate and potassium bicarbonate were added to a calcium-oxalate lithogenic diet (a glycolic-acid diet) in order to determine their effects in preventing lithogenicity. Male Wistar-strain rats who had been fed the glycolic-acid diet developed marked urinary calculi within four weeks. Rats in the sodium and potassium pyruvate groups had, however, almost no stones in the urinary system. Rats in the bicarbonate and pyruvic-acid groups showed slightly less effect than those in the pyruvate groups. Urinary oxalate excretion was high in all the groups during the experiment. The urinary oxalate concentration was relatively higher in the sodium-pyruvate group, and significantly higher in the potassium-pyruvate group, than in the glycolic-acid group. Urinary citrate excretion was high both in the pyruvate and bicarbonate groups; the urinary citrate concentration was, however, significantly higher in the pyruvate groups than in the bicarbonate groups at the fourth experimental week. The urinary calcium and magnesium concentrations were irrelevant to the diets administered. Therefore, it can be concluded that pyruvate salts inhibit urinary calculi formation, not by decreasing oxalate synthesis, but by increasing the urinary citrate concentration; bicarbonate salts work in the same manner, but a little less effectively. PMID:3007782

  14. [*calcium-oxalate lithogenesis: crystallization in the presence of urine from healthy subjects].

    PubMed

    Beaufays, J P; Bouche, R; Boistelle, R

    1995-01-01

    In the present study we aim at describing the influence of urine of non-lithiasic subjects on the different crystallization stages of calcium oxalates. The experimental method consists in comparing the turbidimetric curves obtained by crystallization in pure synthetic urine to the curves obtained after addition of natural urine to the solution. Natural urine plays an important role on nucleation, crystal growth and agglomeration even if only small amounts (4% v/v) are added to the mother solution. Nucleation is favoured (decrease of the induction period and increase of the crystal number) by the presence of solid particles, such as cellular fragments, which play the role of substrates for heterogeneous nucleation. On the other hand, both the growth rate of the crystals and their degree of agglomeration are reduced. Moreover, the physical nature of the crystals which precipitate is different from that of the crystals which nucleate in synthetic urine. Under our conditions of high super-saturation, natural urine favours the nucleation of calcium oxalate dihydrate at the expenses of calcium oxalate trihydrate which forms in pure synthetic urine. A hypothesis on the origin of the lithogenesis process is made and a correlation between the localization of the calcium oxalate stones in the urinary tracts and their main constituents is proposed. PMID:7630471

  15. Monohydrated alkaline earth metal dications do exist

    NASA Astrophysics Data System (ADS)

    El-Nahas, Ahmed M.

    2001-11-01

    The potential energy surfaces for Be 2+OH 2 and Mg 2+OH 2 dications in the gas phase have been investigated at B3LYP and CCSD(T) levels of theory. Different dissociation channels have been taken into account. The results indicate that the monohydrated Be and Mg dications are thermodynamically and kinetically stable species and coulomb explosion is hindered by a barrier of 57-75 kcal/mol. The Be 2+OH 2 and Mg 2+OH 2 dications can dissociate to M + and +OH2 if sufficient kinetic energy is given to the system.

  16. Effect of vitamin D3 on the conversion of ethylene glycol to glycolate and oxalate in ethylene glycol-fed rats.

    PubMed

    Halabe, A; Shor, R; Wong, N L M; Sutton, R A L

    2003-04-01

    Hypercalciuria and hyperoxaluria are important risk factors in the pathogenesis of kidney stones. Urinary glycolate has also been reported to be elevated in patients with renal stones. 1,25-Dihydroxyvitamin D(3), the active metabolite of vitamin D, has been reported to induce hyperoxaluria after either oral or intravenous administration. 1-alpha-D(3), a synthetic derivative of vitamin D, together with ethylene glycol, has been reported to induce renal stones in experimental rats. We have examined the effect of 1-alpha-vitamin D(3) on urinary oxalate and glycolate excretion. Our results indicate that 1-alpha-D(3), together with ethylene glycol, caused a significant increase in urinary glycolate, without a parallel rise in urinary oxalate excretion, in ethylene glycol-fed rats. This increase in urinary glycolate was due to the synergistic effect of both drugs. PMID:12636932

  17. Kidney Stones (For Parents)

    MedlinePLUS

    ... in urine (pee) become extra concentrated and form crystals. Over a few weeks or months, the crystals can build up and become stones. Kidney stones ... changes the level of a substance in it, crystals can begin to form. The crystals can become ...

  18. Chimpanzee accumulative stone throwing

    PubMed Central

    Kühl, Hjalmar S.; Kalan, Ammie K.; Arandjelovic, Mimi; Aubert, Floris; D’Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E.; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J.; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M.; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites. PMID:26923684

  19. Old Stone Field Marker

    USGS Multimedia Gallery

    This is a stone field marker that marked boundaries for land ownership. In the early days of Land Office Recordings, this is one type of monument used. Trees, Posts, Iron Pipes and as shown stones were used to mark off land during the Land Rush days. Later, when mapping was being done, Brass Caps wi...

  20. SOURCE ASSESSMENT: CRUSHED STONE

    EPA Science Inventory

    This report describes a study of air emissions from crushed stone production. The potential environmental effect of the source is evaluated. Crushed stone production in 1972 was 1.07 x 10 to the 8th power metric tons (1.18 x 10 to the 8th power tons), 68% of which was traprock. C...

  1. Chimpanzee accumulative stone throwing.

    PubMed

    Kühl, Hjalmar S; Kalan, Ammie K; Arandjelovic, Mimi; Aubert, Floris; D'Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites. PMID:26923684

  2. Caffeine intake and the risk of kidney stones123

    PubMed Central

    Taylor, Eric N; Gambaro, Giovanni; Curhan, Gary C

    2014-01-01

    Background: Although caffeine intake may increase urine calcium excretion, caffeine-containing beverages have been associated with a lower risk of nephrolithiasis. Objective: We sought to determine the association between caffeine intake and the risk of incident kidney stones in 3 large prospective cohorts. Design: We prospectively analyzed the association between intake of caffeine and incidence of kidney stones in 3 large ongoing cohort studies, the Health Professionals Follow-Up Study (HPFS) and the Nurses Health Studies (NHS) I and II. Information on the consumption of caffeine and the incidence of kidney stones was collected by validated questionnaires. Results: The analysis included 217,883 participants; over a median follow-up of >8 y, 4982 incident cases occurred. After multivariate adjustment for age, BMI, fluid intake, and other factors, participants in the highest quintile of caffeine intake had a 26% (95% CI: 12%, 38%) lower risk of developing stones in the HPFS cohort, a 29% lower risk (95% CI: 15%, 41%) in the NHS I cohort, and a 31% lower risk (95% CI: 18%, 42%) in the NHS II cohort (P-trend < 0.001 for all cohorts). The association remained significant in the subgroup of participants with a low or no intake of caffeinated coffee in the HPFS cohort. Among 6033 participants with 24-h urine data, the intake of caffeine was associated with higher urine volume, calcium, and potassium and with lower urine oxalate and supersaturation for calcium oxalate and uric acid. Conclusion: Caffeine intake is independently associated with a lower risk of incident kidney stones. PMID:25411295

  3. Raman spectroscopic analysis of the calcium oxalate producing extremotolerant lichen Circinaria gyrosa

    NASA Astrophysics Data System (ADS)

    Böttger, U.; Meessen, J.; Martinez-Frias, J.; Hübers, H.-W.; Rull, F.; Sánchez, F. J.; de la Torre, R.; de Vera, J.-P.

    2014-01-01

    In the context of astrobiological exposure and simulation experiments in the BIOMEX project, the lichen Circinaria gyrosa was investigated by Raman microspectroscopy. Owing to the symbiotic nature of lichens and their remarkable extremotolerance, C. gyrosa represents a valid model organism in recent and current astrobiological research. Biogenic compounds of C. gyrosa were studied that may serve as biomarkers in Raman assisted remote sensing missions, e.g. ExoMars. The surface as well as different internal layers of C. gyrosa have been characterized and data on the detectability and distribution of β-carotene, chitin and calcium oxalate monohydrate (whewellite) are presented in this study. Raman microspectroscopy was applied on natural samples and thin sections. Although calcium oxalates can also be formed by rare geological processes it may serve as a suitable biomarker for astrobiological investigations. In the model organism C. gyrosa, it forms extracellular crystalline deposits embedded in the intra-medullary space and its function is assumed to balance water uptake and gas exchange during the rare, moist to wet environmental periods that are physiologically favourable. This is a factor that was repeatedly demonstrated to be essential for extremotolerant lichens and other organisms. Depending on the decomposition processes of whewellite under extraterrestrial environmental conditions, it may not only serve as a biomarker of recent life, but also of past and fossilized organisms.

  4. Anhydrous Amorphous Calcium Oxalate Nanoparticles from Ionic Liquids: Stable Crystallization Intermediates in the Formation of Whewellite.

    PubMed

    Gehl, Aaron; Dietzsch, Michael; Mondeshki, Mihail; Bach, Sven; Häger, Tobias; Panthöfer, Martin; Barton, Bastian; Kolb, Ute; Tremel, Wolfgang

    2015-12-01

    The mechanisms by which amorphous intermediates transform into crystalline materials are not well understood. To test the viability and the limits of the classical crystallization, new model systems for crystallization are needed. With a view to elucidating the formation of an amorphous precursor and its subsequent crystallization, the crystallization of calcium oxalate, a biomineral widely occurring in plants, is investigated. Amorphous calcium oxalate (ACO) precipitated from an aqueous solution is described as a hydrated metastable phase, as often observed during low-temperature inorganic synthesis and biomineralization. In the presence of water, ACO rapidly transforms into hydrated whewellite (monohydrate, CaC2 O4 ⋅H2 O, COM). The problem of fast crystallization kinetics is circumvented by synthesizing anhydrous ACO from a pure ionic liquid (IL-ACO) for the first time. IL-ACO is stable in the absence of water at ambient temperature. It is obtained as well-defined, non-agglomerated particles with diameters of 15-20 nm. When exposed to water, it crystallizes to give (hydrated) COM through a dissolution/recrystallization mechanism. PMID:26549793

  5. Oxalate content of silver beet leaves (Beta vulgaris var. cicla) at different stages of maturation and the effect of cooking with different milk sources.

    PubMed

    Simpson, Thomas S; Savage, Geoffrey P; Sherlock, Robert; Vanhanen, Leo P

    2009-11-25

    The work presented here indicates that people who have a tendency to develop kidney stones should avoid consuming regrowth and developed silver beet (Beta vulgaris var. cicla) leaves. Soluble oxalate contents of leaves range from 58% of the total oxalate for the mature leaves up to 89% for the regrowth tissue, with regrowth tissue containing the highest levels of soluble oxalate at 7267+/-307 mg/100 g of dry matter (DM). Leaves cooked in milk contained significantly (p<0.05) lower levels of soluble oxalate compared to the leaves that were cooked in water. Leaves cooked in low fat milk contained significantly lower levels (p<0.05) of soluble oxalate (1.9%) than leaves cooked in standard milk (5.3%) or cream (6.3%). To maximize the reduction of soluble oxalate during the cooking of high oxalate foods such as spinach and silver beet, a low fat milk cooking medium with neutral pH should be utilized. PMID:19877639

  6. 12. FLOOR 2; STONE CRANE IN PLACE FOR ROCK STONES; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. FLOOR 2; STONE CRANE IN PLACE FOR ROCK STONES; STONE CRANE HAS OAK SPAR, JIB AND BRACE, METAL SCREW, IRON YOKE AND DOGS; IRON PINS FIT THROUGH HOLES IN DOGS INTO HOLES DRILLED IN RUNNER STONE - Hook Windmill, North Main Street at Pantigo Road, East Hampton, Suffolk County, NY

  7. Automated homogeneous oxalate precipitation of Pu(III)

    SciTech Connect

    Yarbro, S.L.; Schreiber, S.B.; Dunn, S.L.; Mills, C.W.

    1990-01-01

    Homogeneous oxalate precipitation using diethyl oxalate was compared to precipitating Pu(III) oxalate with solid oxalic acid. The diethyl oxalate technique at 75{degree}C is better because it gives 50% less plutonium in the filtrate with a reasonable filtering time. Also, the procedure for the homogeneous precipitation is easier to automate because the liquid diethyl oxalate is simpler to introduce into the precipitator than solid oxalic acid. It also provides flexibility because the hydrolysis rate and therefore the precipitation rate can be controlled by varying the temperature. 5 refs., 3 figs., 3 tabs.

  8. Artificial photosynthesis of oxalate and oxalate-based polymer by a photovoltaic reactor

    PubMed Central

    Nong, Guangzai; Chen, Shan; Xu, Yuanjin; Huang, Lijie; Zou, Qingsong; Li, Shiqiang; Mo, Haitao; Zhu, Pingchuan; Cen, Weijian; Wang, Shuangfei

    2014-01-01

    A photovoltaic reactor was designed for artificial photosynthesis, based on the reactions involved in high energy hydrogen atoms, which were produced from water electrolysis. Water and CO2, under the conditions studied, were converted to oxalate (H2C2O4) and a polymer. This was the first time that the oxalates and oxalate-based polymer were produced from the artificial photosynthesis process. PMID:24389750

  9. Photoconductivity of Yttrium Neodymium Gadolinium Oxalate Crystals

    NASA Astrophysics Data System (ADS)

    Kuryan, Soosy; Abraham, Rosalin; Isac, Jayakumari

    2007-03-01

    Crystals are pillars of modern technology..Yttrium Neodymium Gadolinium oxalate (YNdGaOx) crystals were grown by gel method by the diffusion of Yttrium Chloride, Neodymium Chloride, and Gadolinium Chloride into the set gel containing Oxalic acid. Silica gel method is capable of yielding crystals of high optical perfection and wide morphology. The growing crystals are held in the gel medium in a strain free manner and at the same time nucleation and super saturation are well controlled. Photo conductivity studies of these crystals revealed negative photoconductivity nature. The photocurrent is found to be less than the dark current at every applied electric field. Rare Earth compounds are known for their interesting electric, magnetic and luminescent properties. Recent investigations on the fluorescence of some rare earth oxalates suggest their potentiality for their optical applications. Rare Earth oxalates evoked greater attention because of their ionic conduction.

  10. Photoconductivity of Yttrium Praseodymium Gadolinium Oxalate Crystals

    NASA Astrophysics Data System (ADS)

    Kuryan, Soosy; Abraham, Rosalin; Isac, Jayakumari

    2007-06-01

    Crystals are pillars of modern technology. Yttrium Praseodymium Gadolinium oxalate (YPrGaOx) crystals were grown by gel method by the diffusion of Yttrium Chloride, Praseodymium Chloride, and Gadolinium Chloride into the set gel containing Oxalic acid. Silica gel method is capable of yielding crystals of high optical perfection and wide morphology. The growing crystals are held in the gel medium in a strain free manner and at the same time nucleation and super saturation are well controlled. Photo conductivity studies of these crystals revealed negative photoconductivity nature. The photocurrent is found to be less than the dark current at every applied electric field. Rare Earth compounds are known for their interesting electric, magnetic and luminescent properties. Recent investigations on the fluorescence of some rare earth oxalates suggest their potentiality for their optical applications. Rare Earth oxalates evoked greater attention because of their ionic conduction.

  11. Chaga mushroom-induced oxalate nephropathy.

    PubMed

    Kikuchi, Yuko; Seta, Koichi; Ogawa, Yayoi; Takayama, Tatsuya; Nagata, Masao; Taguchi, Takashi; Yahata, Kensei

    2014-06-01

    Chaga mushrooms have been used in folk and botanical medicine as a remedy for cancer, gastritis, ulcers, and tuberculosis of the bones. A 72-year-old Japanese female had been diagnosed with liver cancer 1 year prior to presenting at our department. She underwent hepatectomy of the left lobe 3 months later. Chaga mushroom powder (4 - 5 teaspoons per day) had been ingested for the past 6 months for liver cancer. Renal function decreased and hemodialysis was initiated. Renal biopsy specimens showed diffuse tubular atrophy and interstitial fibrosis. Oxalate crystals were detected in the tubular lumina and urinary sediment and oxalate nephropathy was diagnosed. Chaga mushrooms contain extremely high oxalate concentrations. This is the first report of a case of oxalate nephropathy associated with ingestion of Chaga mushrooms. PMID:23149251

  12. 21 CFR 520.608 - Dicloxacillin sodium monohydrate capsules.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... monohydrate equivalent to 50, 100, 200, or 500 milligrams of dicloxacillin. (b) Sponsor. See No. 000856 in... body weight, three times daily. In severe cases, up to 25 milligrams per pound of body weight...

  13. Adaptable coordination of U(IV) in the 2D-(4,4) uranium oxalate network: From 8 to 10 coordinations in the uranium (IV) oxalate hydrates

    SciTech Connect

    Duvieubourg-Garela, L.; Vigier, N. Grandjean, S.

    2008-08-15

    Crystals of uranium (IV) oxalate hydrates, U(C{sub 2}O{sub 4}){sub 2}.6H{sub 2}O (1) and U(C{sub 2}O{sub 4}){sub 2}.2H{sub 2}O (2), were obtained by hydrothermal methods using two different U(IV) precursors, U{sub 3}O{sub 8} oxide and nitric U(IV) solution in presence of hydrazine to avoid oxidation of U(IV) into uranyl ion. Growth of crystals of solvated monohydrated uranium (IV) oxalate, U(C{sub 2}O{sub 4}){sub 2}.H{sub 2}O.(dma) (3), dma=dimethylamine, was achieved by slow diffusion of U(IV) into a gel containing oxalate ions. The three structures are built on a bi-dimensional complex polymer of U(IV) atoms connected through bis-bidentate oxalate ions forming [U(C{sub 2}O{sub 4})]{sub 4} pseudo-squares. The flexibility of this supramolecular arrangement allows modifications of the coordination number of the U(IV) atom which, starting from 8 in 1 increases to 9 in 3 and, finally increases, to 10 in 2. The coordination polyhedron changes from a distorted cube, formed by eight oxygen atoms of four oxalate ions, in 1, to a mono-capped square anti-prism in 3 and, finally, to a di-capped square anti-prism in 2, resulting from rotation of the oxalate ions and addition of one and two water oxygen atoms in the coordination of U(IV). In 1, the space between the {sub {infinity}}{sup 2}[U(C{sub 2}O{sub 4}){sub 2}] planar layers is occupied by non-coordinated water molecules; in 2, the space between the staggered {sub {infinity}}{sup 2}[U(C{sub 2}O{sub 4}){sub 2}.2H{sub 2}O] layers is empty, finally in 3, the solvate molecules occupy the interlayer space between corrugated {sub {infinity}}{sup 2}[U(C{sub 2}O{sub 4}){sub 2}.H{sub 2}O] sheets. The thermal decomposition of U(C{sub 2}O{sub 4}){sub 2}.6H{sub 2}O under air and argon atmospheres gives U{sub 3}O{sub 8} and UO{sub 2}, respectively. - Graphical abstract: The adaptable environment of U(IV) in U(IV) oxalates: from eight cubic coordination in U(C{sub 2}O{sub 4}){sub 2}.6H{sub 2}O (a) completed by water oxygens to nine in [U(C{sub 2}O{sub 4}){sub 2}.H{sub 2}O](C{sub 2}NH{sub 5}) (b) and ten coordination in U(C{sub 2}O{sub 4}){sub 2}.2H{sub 2}O (c)

  14. Modeling the Adsorption of Oxalate onto Montmorillonite.

    PubMed

    Ramos, M Elena; Emiroglu, Caglayan; Garca, David; Sainz-Daz, C Ignacio; Huertas, F Javier

    2015-11-01

    In this work, a multiscale modeling of the interaction of oxalate with clay mineral surfaces from macroscale thermodynamic equilibria simulations to atomistic calculations is presented. Previous results from macroscopic adsorption data of oxalate on montmorillonite in 0.01 M KNO3 media at 25 C within the pH range from 2.5 to 9 have been used to develop a surface complexation model. The experimental adsorption edge data were fitted using the triple-layer model (TLM) with the aid of the FITEQL 4.0 computer program. Surface complexation of oxalate is described by two reactions: >AlOH + Ox(2-) + 2H(+) = >AlOxH + H2O (log K = 14.39) and >AlOH + Ox(2-) + H(+) = >AlOx(-) + H2O (log K = 10.39). The monodentate complex >AlOxH dominated adsorption below pH 4, and the bidentate complex >AlOx(-) was predominant at higher pH values. Both of the proposed inner-sphere oxalate species are qualitatively consistent with previously published diffuse reflectance FTIR spectroscopic results for oxalate on montmorillonite edge surface (Chem. Geol. 2014, 363, 283-292). Atomistic computational studies have been performed to understand the interactions at the molecular level between adsorbates and mineral surface, showing the atomic structures and IR frequency shifts of the adsorption complexes of oxalate with the edge surface of a periodic montmorillonite model. PMID:26444928

  15. Effect of Lagenaria siceraria fruit powder on sodium oxalate induced urolithiasis in Wistar rats

    PubMed Central

    Takawale, Rahul V.; Mali, Vishal R.; Kapase, Chinmay U.; Bodhankar, Subhash L.

    2012-01-01

    Background: In spite of advances in the present practice of medicine, the formation and growth of calculi continues to trouble mankind, as there is no satisfactory drug to treat kidney stones. In India, many indigenous drugs are in use for the treatment of urinary calculus disease. Objective: The present study was intended to determine anti-urolithiatic effect of Lagenaria siceraria fruit powder (LSFP) against sodium oxalate (NaOx) induced urolithiasis in rats. Materials and Methods: Animals were grouped as Vehicle Group (received vehicle gum acacia 2% w/v 1 mL/kg/p.o.), NaOx Group(Sodium oxalate 70 mg/kg,i.p.), LSFP Group (500 mg/kg, p.o. LSFP suspended in gum acacia 2% + Sodium oxalate 70 mg/kg), Cystone Group (500 mg/kg, p.o. Cystone suspended in gum acacia 2% + Sodium oxalate 70 mg/kg). Result: The increased severity of microscopic calcium oxalate (CaOx) crystals deposition along with increased concentration in the kidney was seen after 7 days of NaOx (70 mg/kg, i.p.) pre-treatment. LSFP (500 mg/kg, p.o.) and standard marketed formulation Cystone (500 mg/kg, p.o.) caused a significant reversal of NaOx-induced changes in ion excretion and urinary CaOx concentration in 7 days treatment. Conclusion: From the results, it was concluded that LSFP showed beneficial effect against urolithiasis by decreasing CaOx excretion and preventing crystal deposition in the kidney tubules. PMID:22707863

  16. Oxygen nano-bubble water reduces calcium oxalate deposits and tubular cell injury in ethylene glycol-treated rat kidney.

    PubMed

    Hirose, Yasuhiko; Yasui, Takahiro; Taguchi, Kazumi; Fujii, Yasuhiro; Niimi, Kazuhiro; Hamamoto, Shuzo; Okada, Atsushi; Kubota, Yasue; Kawai, Noriyasu; Itoh, Yasunori; Tozawa, Keiichi; Sasaki, Shoichi; Kohri, Kenjiro

    2013-08-01

    Renal tubular cell injury induced by oxalate plays an important role in kidney stone formation. Water containing oxygen nano-bubbles (nanometer-sized bubbles generated from oxygen micro-bubbles; ONB) has anti-inflammatory effects. Therefore, we investigated the inhibitory effects of ONB water on kidney stone formation in ethylene glycol (EG)-treated rats. We divided 60 rats, aged 4weeks, into 5 groups: control, the water-fed group; 100% ONB, the 100% ONB water-fed group; EG, the EG treated water-fed group; EG+50% ONB and EG+100% ONB, water containing EG and 50% or 100% ONB, respectively. Renal calcium oxalate (CaOx) deposition, urinary excretion of N-acetyl-?-D-glucosaminidase (NAG), and renal expression of inflammation-related proteins, oxidative stress biomarkers, and the crystal-binding molecule hyaluronic acid were compared among the 5 groups. In the control and 100% ONB groups, no renal CaOx deposits were detected. In the EG+50% ONB and EG+100% ONB groups, ONB water significantly decreased renal CaOx deposits, urinary NAG excretion, and renal monocyte chemoattractant protein-1, osteopontin, and hyaluronic acid expression and increased renal superoxide dismutase-1 expression compared with the EG group. ONB water substantially affected kidney stone formation in the rat kidney by reducing renal tubular cell injury. ONB water is a potential prophylactic agent for kidney stones. PMID:23754513

  17. Skimming and Skipping Stones

    ERIC Educational Resources Information Center

    Humble, Steve

    2007-01-01

    This article presents an example of skimming and skipping stone motion in mathematical terms available to students studying A-level mathematics. The theory developed in the article postulates a possible mathematical model that is verified by experimental results.

  18. Adenoid Stones Adenoliths

    PubMed Central

    Sakano, Hitomi; Thaker, Ameet I.; Davis, Greg E.

    2015-01-01

    Stones made of bacterial aggregates can be found in chronically inflamed lymphoid tissue such as hypertrophied tonsils. Although it is common to find tonsilloliths in cryptic tonsils, it is rare to find stones in adenoid tissue. Here we present an interesting case of a patient who underwent adenoidectomy for adenoid hypertrophy, recurrent malaise and upper respiratory infections. Intraoperatively we found numerous bright green stones in the crypts of the adenoid tissue, reminiscent of tonsilloliths in tonsillar crypts. Pathology revealed polymicrobial bacterial aggregates surrounded by neutrophils. Our findings suggest that the pathophysiology is similar to that of tonsillolith formation. Thus, we should at least consider the presence of adenoid stones and consider adenoidectomy for symptoms often attributed to tonsilloliths. We have coined the term adenoliths to describe this interesting finding and present it as a potential source of recurrent infection. PMID:26798664

  19. Kidney Stones in Children

    MedlinePLUS

    ... Nephrology American Kidney Fund National Kidney Foundation MedlinePlus Kidney and Urologic Disease Organizations Many organizations provide support ... Disease Organizations​​ . (PDF, 345 KB) Alternate Language URL Kidney Stones in Children Page Content On this page: ...

  20. High precision mapping of kidney stones using μ-IR spectroscopy to determine urinary lithogenesis.

    PubMed

    Blanco, Francisco; Ortiz-Alías, Pilar; López-Mesas, Montserrat; Valiente, Manuel

    2015-06-01

    Evolution of urinary lithiasis is determined by the metabolism and life-style of the related patient. The appropriate classification of the stone is mandatory for the identification of the lithogenic process. In this study, cros-sections from a single stone of each of the most frequent urolithiasis types (calcium oxalate mono and dihydrate and carbonate apatite) have been selected and imaged using IR microspectroscopy. Moreover, the use of high definition sFTIR (synchrotron source) has revealed hidden information to the conventional FTIR. This work has demonstrated that minor components become key factors on the description of the stages of stone formation. Intensity map for COM (1630 cm(-1) peak). The high spatial definition achieved is key for the precise description of the kidney stone history. PMID:25091212

  1. 9-O-Ethylberberrubinium iodide monohydrate

    PubMed Central

    Grundt, Peter; Pernat, Jennifer; Krivogorsky, Bogdana; Halverson, Melanie A.; Berry, Steven M.

    2010-01-01

    In the title compound (systematic name: 9-ethoxy-10-methoxy-5,6-dihydro-1,3-dioxolo[4,5-g]isoquinolino[3,2-a]isoquinolin-7-ium iodide monohydrate), 2C21H20NO4 +2I?H2O, two independent molecules pack in the unit cell, where interactions between the molecules are stabilized by weak intermolecular ?? stacking interactions [centroidcentroid distances in the range 3.571?(4) to 3.815?(4)]. Intermolecular CH?O interactions are also observed. The iodide anions are disordered with occupancy ratios of 0.94?(1):0.06?(1) and 0.91?(1):0.09?(1). The cationic molecule is planar in structure with a small torsion resulting from the dihydropyridine ring. PMID:21587567

  2. The Relationship between Serum Oxalic Acid, Central Hemodynamic Parameters and Colonization by Oxalobacter formigenes in Hemodialysis Patients

    PubMed Central

    Gulhan, Baris; Turkmen, Kultigin; Aydin, Merve; Gunay, Murat; C?kman, Aytekin; Kara, Murat

    2015-01-01

    Background/Objective Elevated pulse wave velocity (PWV) and central aortic blood pressures are independent predictors of increased cardiovascular morbidity and mortality in hemodialysis (HD) patients. Oxalic acid is a uremic retention molecule that is extensively studied in the pathogenesis of calcium oxalate stones. Oxalobacter formigenes, a member of the colon microbiota, has important roles in oxalate homeostasis. Data regarding the colonization by and the exact role of O. formigenes in the pathogenesis of oxalic acid metabolism in HD patients are scant. Hence, we aimed to determine the relationship between fecal O. formigenes colonization, serum oxalic acid and hemodynamic parameters in HD patients with regard to the colo-reno-cardiac axis. Methods Fifty HD patients were enrolled in this study. PWV and central aortic systolic (cASBP) and diastolic blood pressures (cADBP) were measured with a Mobil-O-Graph (I.E.M. GmbH, Stolberg, Germany). Serum oxalic acid levels were assessed by ELISA, and fecal O. formigenes DNA levels were isolated and measured by real-time PCR. Results Isolation of fecal O. formigenes was found in only 2 HD patients. One of them had 113,609 copies/ml, the other one had 1,056 copies/ml. Serum oxalic acid levels were found to be positively correlated with PWV (r = 0.29, p = 0.03), cASBP (r = 0.33, p = 0.001) and cADBP (r = 0.42, p = 0.002) and negatively correlated with LDL (r = ?0.30, p = 0.03). In multivariate linear regression analysis, PWV was independently predicted by oxalic acid, glucose and triglyceride. Conclusions This is the first study that demonstrates the absence of O. formigenes as well as a relation between serum oxalic acid and cASBP, cADBP and PWV in HD patients. Replacement of O. formigenes with pre- and probiotics might decrease serum oxalic acid levels and improve cardiovascular outcomes in HD patients. PMID:26195968

  3. Bifunctional hydrogen bonds in monohydrated cycloether complexes.

    PubMed

    Vallejos, Margarita M; Angelina, Emilio L; Peruchena, Nlida M

    2010-03-01

    In this work, the cooperative effects implicated in bifunctional hydrogen bonds (H-bonds) were studied (in monohydrated six-membered cycloether) within the framework of the atoms in molecules (AIM) theory and of the natural bond orbitals (NBO) analysis. The study was carried out in complexes formed by six-membered cycloether compounds (tetrahydropyrane, 1,4-dioxane, and 1,3-dioxane) and a water molecule. These compounds were used as model systems instead of more complicated molecules of biological importance. All the results were obtained at the second-order Mller-Plesset (MP2) level theory using a 6-311++G(d,p) basis set. Attention was focused on the indicators of the cooperative effects that arise when a water molecule interacts simultaneously with a polar and a nonpolar portion of a six-membered cycloether (via bifunctional hydrogen bonds) and compared with conventional H-bonds where the water molecule only interacts with the polar portion of the cycloether. Different indicators of H-bonds strength, such as structural and spectroscopic data, electron charge density, population analysis, hyperconjugation energy and charge transference, consistently showed significant cooperative effects in bifunctional H-bonds. From the AIM, as well as from the NBO analysis, the obtained results allowed us to state that in the monohydrated six-membered cycloether, where the water molecule plays a dual role, as proton acceptor and proton donor, a mutual reinforcement of the two interactions occurs. Because of this feature, the complexes engaged by bifunctional hydrogen bonds are more stabilized than the complexes linked by conventional hydrogen bonds. PMID:20136161

  4. Bacteriological study and structural composition of staghorn stones removed by the anatrophic nephrolithotomic procedure.

    PubMed

    Shafi, Hamid; Shahandeh, Zahra; Heidari, Behzad; Sedigiani, Farahnaz; Ramaji, Arsalan Ali; Pasha, Yousef Reza Yousefnia; Kassaeian, Ali Akbar; Pasha, Abazar Akbarzadeh; Mir, Mir Muhammad Reza Aghajani

    2013-03-01

    This study was conducted to determine the composition of staghorn stones and to assess the proportion of infected stones as well as the correlation between infection in the stones and bacteria grown in urine. Samples of 45 consecutive stones removed through anatrophic nephrolithotomic procedures were taken from the operation site and samples of urine were obtained by simultaneous bladder catheterization. The frequency of infection in the stones and correlation between infection of stone and urine samples were determined with respect to the composition of the stones. Twenty-two males and 23 females, with respective mean ages of 48.3 15.6 years and 51 7.4 years, were studied. The stone and urine cultures yielded positive results in ten and 16 patients, respectively, of a total of 45 patients (22.2% and 35.5%, respectively). Calcium oxalate was the main constituent of staghorn stones, seen in 31 patients (68.8%), uric acid in 12 patients (26.6%) and struvite and/or calcium phosphate in 11 patients (24.4%). In seven of ten stones with bacterial growth, bacteria were isolated from urine cultures as well, which accounted for a concordance rate of 70%. The bacteria grown in the stone were the cause of urinary tract infection (UTI) in 43.5% of the cases. Stone infection was significantly associated with UTI (OR = 6.47; 95% CI 1.43-31.7, P = 0.021) and presence of phosphate in the stones (OR = 18, 95% CI 3.28-99.6, P = 0.0006). E. coli was the most common bacteria grown from the stones, and was isolated in 50% of the cases; Ureaplasma urealyticum was the most common organism causing UTI, grown in 62.5% of the urine samples. There was a high concordance rate between bacteria in the stones and urine. These findings indicate that the urine culture can provide information for selection of an appropriate anti-microbial agent for stone sterilization. In addition, preventing re-growth or recurrence of stones and treatment of post-surgical infections would be facilitated based on the results of the urine culture. PMID:23538378

  5. Hippuric Acid as a Significant Regulator of Supersaturation in Calcium Oxalate Lithiasis: The Physiological Evidence

    PubMed Central

    Atanassova, Stoyanka S.; Gutzow, Ivan S.

    2013-01-01

    At present, the clinical significance of existing physicochemical and biological evidence and especially the results we have obtained from our previous in vitro experiments have been analyzed, and we have come to the conclusion that hippuric acid (C6H5CONHCH2COOH) is a very active solvent of Calcium Oxalate (CaOX) in physiological solutions. Two types of experiments have been discussed: clinical laboratory analysis on the urine excretion of hippuric acid (HA) in patients with CaOX lithiasis and detailed measurements of the kinetics of the dissolution of CaOX calculi in artificial urine, containing various concentrations of HA. It turns out that the most probable value of the HA concentration in the control group is approximately ten times higher than the corresponding value in the group of the stone-formers. Our in vitro analytical measurements demonstrate even a possibility to dissolve CaOX stones in human urine, in which increased concentration of HA have been established. A conclusion can be that drowning out HA is a significant regulator of CaOX supersaturation and thus a regulation of CaOX stone formation in human urine. Discussions have arisen to use increased concentration of HA in urine both as a solubilizator of CaOX stones in the urinary tract and on the purpose of a prolonged metaphylactic treatment. PMID:24307993

  6. Probiotics and Other Key Determinants of Dietary Oxalate Absorption1

    PubMed Central

    Liebman, Michael; Al-Wahsh, Ismail A.

    2011-01-01

    Oxalate is a common component of many foods of plant origin, including nuts, fruits, vegetables, grains, and legumes, and is typically present as a salt of oxalic acid. Because virtually all absorbed oxalic acid is excreted in the urine and hyperoxaluria is known to be a considerable risk factor for urolithiasis, it is important to understand the factors that have the potential to alter the efficiency of oxalate absorption. Oxalate bioavailability, a term that has been used to refer to that portion of food-derived oxalate that is absorbed from the gastrointestinal tract (GIT), is estimated to range from 2 to 15% for different foods. Oxalate bioavailability appears to be decreased by concomitant food ingestion due to interactions between oxalate and coingested food components that likely result in less oxalic acid remaining in a soluble form. There is a lack of consensus in the literature as to whether efficiency of oxalate absorption is dependent on the proportion of total dietary oxalate that is in a soluble form. However, studies that directly compared foods of varying soluble oxalate contents have generally supported the proposition that the amount of soluble oxalate in food is an important determinant of oxalate bioavailability. Oxalate degradation by oxalate-degrading bacteria within the GIT is another key factor that could affect oxalate absorption and degree of oxaluria. Studies that have assessed the efficacy of oral ingestion of probiotics that provide bacteria with oxalate-degrading capacity have led to promising but generally mixed results, and this remains a fertile area for future studies. PMID:22332057

  7. Diagnosis of rare inherited glyoxalate metabolic disorders through in-situ analysis of renal stones

    NASA Astrophysics Data System (ADS)

    Jacob, D. E.; Grohe, B.; Hoppe, B.; Beck, B. B.; Tessadri, R.

    2012-04-01

    The primary hyperoxalurias type I - III constitute rare autosomal-recessive inherited disorders of the human glyoxylate metabolism. By mechanisms that are ill understood progressive nephrocalcinosis and recurrent urolithiasis (kidney stone formation) often starting in early childhood, along with their secondary complications results in loss of nephron mass which progresses to end-stage renal failure over time. In the most frequent form, end-stage renal failure (ESRF) is the rule and combined liver/kidney transplantation respectively pre-emptive liver transplantation are the only causative treatment today. Hence, this contributes significantly to healthcare costs and early diagnosis is extremely important for a positive outcome for the patient. We are developing a stone-based diagnostic method by in-detail multi-methods investigation of the crystalline moiety in concert with urine and stone proteomics. Stone analysis will allow faster analysis at low-impact for the patients in the early stages of the disease. First results from combined spectroscopic (Raman, FTIR)and geochemical micro-analyses (Electron Microprobe and Laser Ablation ICP-MS) are presented here that show significant differences between stones from hyperoxaluria patients and those formed by patients without this disorder (idiopathic stones). Major differences exist in chemistry as well as in morphology and phase composition of the stones. Ca/P ratios and Mg contents differentiate between oxalate-stones from hyperoxaluria patients and idiopathic stones. Results show that also within the different subtypes of primary hyperoxaluria significant differences can be found in stone composition. These imply differences in stone formation which could be exploited for new therapeutic pathways. Furthermore, the results provide important feedback for suspected but yet unconfirmed cases of primary hyperoxaluria when used in concert with the genetic methods routinely applied.

  8. Biochemical changes in kidneys of normal and stone forming rats with sodium pentosan polysulphate.

    PubMed

    Subha, K; Baskar, R; Varalakshmi, P

    1992-02-01

    The influence of sodium pentosan polysulphate was studied on the deposition of stone forming constituents along with certain enzymes in the renal tissue of experimentally induced urolithiatic rats. Calcium, oxalate and phosphorus levels were elevated in kidneys of lithogenic rats, while SPP administration reduced these levels to near control values. The elevation in kidney LDH was significant in the stone forming groups and SPP had minimal effect. Increases in the activities of Na+, K(+)-and Ca(2+)-ATPases in the calculogenic groups was lowered considerably with SPP treatment. Inorganic pyrophosphatase activity was reduced significantly in the calculogenic as well as in the drug treated groups. Leucine aminopeptidase was decreased in the calculogenic group. SPP treatment elevated the enzyme activity in the treated groups. Reduction in kidney oxalate with SPP may prove useful in the medical management of urolithiasis. PMID:1373054

  9. Biochemical diagnosis in 3040 kidney stone formers in Argentina.

    PubMed

    Spivacow, Francisco Rodolfo; del Valle, Elisa Elena; Negri, Armando Luis; Fradinger, Erich; Abib, Anabella; Rey, Paula

    2015-08-01

    Nephrolithiasis is a frequent condition in urology that has an important recurrence and high impact in health economy. Knowing the biochemical abnormalities implicated in its pathogenesis is mandatory to establish therapeutic aims. Our objectives are to present the results in 3040 kidney stone formers in Argentina. All patients were selected after completing an ambulatory metabolic protocol with diagnostic purposes. There were 1717 men, (56.48%), with a mean age of 45±12 years, and 1323 women, (43.52%), mean age 44±12 years. 2781 patients had biochemical abnormalities, (91.49%), and were arbitrarily divided in two groups: those who had only one (single) biochemical abnormality (n=2156) and those who had associated abnormalities (n=625). No biochemical abnormalities were found in 259 patients (8.51%). The abnormalities present, single and associated, in order of frequency, were idiopathic hypercalciuria, (56.88%), hyperuricosuria (21.08%), unduly acidic urine (10.95%), hypocitraturia (10.55%), hypomagnesuria (7.9%), primary hyperparathyroidism (3.01%), hyperoxaluria (2.6%), and cystinuria (0.32%). We performed in 484 patient's stone composition and found calcium oxalate stones related to idiopathic hypercalciuria predominantly while uric acid stones to unduly acidic urine. In conclusion, the biochemical abnormalities described are similar to those found in a previous series of our own and to those reported in the literature. Its diagnosis is important to therapeutic purposes to avoid eventual recurrence. PMID:25958053

  10. High variability of the heterogeneous ice nucleation potential of oxalic acid dihydrate and sodium oxalate

    NASA Astrophysics Data System (ADS)

    Wagner, R.; Möhler, O.; Saathoff, H.; Schnaiter, M.; Leisner, T.

    2010-04-01

    The heterogeneous ice nucleation potential of airborne oxalic acid dihydrate and sodium oxalate particles in the deposition and condensation mode has been investigated by controlled expansion cooling cycles in the AIDA aerosol and cloud chamber of the Karlsruhe Institute of Technology at temperatures between 244 and 228 K. Previous laboratory studies have highlighted the particular role of oxalic acid dihydrate as the only species amongst a variety of other investigated dicarboxylic acids to be capable of acting as a heterogeneous ice nucleus in both the deposition and immersion mode. We could confirm a high deposition mode ice activity for 0.03 to 0.8 μm sized oxalic acid dihydrate particles that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets. The critical saturation ratio with respect to ice required for deposition nucleation was found to be less than 1.1 and the size-dependent ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles that had crystallised from less supersaturated solution droplets and had been allowed to slowly grow in a supersaturated environment from still unfrozen oxalic acid solution droplets over a time period of several hours were found to be much poorer heterogeneous ice nuclei. We speculate that under these conditions a crystal surface structure with less-active sites for the initiation of ice nucleation was generated. Such particles partially proved to be almost ice-inactive in both the deposition and condensation mode. At times, the heterogeneous ice nucleation ability of oxalic acid dihydrate significantly changed when the particles had been processed in preceding cloud droplet activation steps. Such behaviour was also observed for the second investigated species, namely sodium oxalate. Our experiments address the atmospheric scenario that coating layers of oxalic acid or its salts may be formed by physical and chemical processing on pre-existing particulates such as mineral dust and soot. Given the broad diversity of the observed heterogeneous ice nucleability of the oxalate species, it is not straightforward to predict whether an oxalate coating layer will improve or reduce the ice nucleation ability of the seed aerosol particles.

  11. High variability of the heterogeneous ice nucleation potential of oxalic acid dihydrate and sodium oxalate

    NASA Astrophysics Data System (ADS)

    Wagner, R.; Möhler, O.; Saathoff, H.; Schnaiter, M.; Leisner, T.

    2010-08-01

    The heterogeneous ice nucleation potential of airborne oxalic acid dihydrate and sodium oxalate particles in the deposition and condensation mode has been investigated by controlled expansion cooling cycles in the AIDA aerosol and cloud chamber of the Karlsruhe Institute of Technology at temperatures between 244 and 228 K. Previous laboratory studies have highlighted the particular role of oxalic acid dihydrate as the only species amongst a variety of other investigated dicarboxylic acids to be capable of acting as a heterogeneous ice nucleus in both the deposition and immersion mode. We could confirm a high deposition mode ice activity for 0.03 to 0.8 μm sized oxalic acid dihydrate particles that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets. The critical saturation ratio with respect to ice required for deposition nucleation was found to be less than 1.1 and the size-dependent ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles that had crystallised from less supersaturated solution droplets and had been allowed to slowly grow in a supersaturated environment from still unfrozen oxalic acid solution droplets over a time period of several hours were found to be much poorer heterogeneous ice nuclei. We speculate that under these conditions a crystal surface structure with less-active sites for the initiation of ice nucleation was generated. Such particles partially proved to be almost ice-inactive in both the deposition and condensation mode. At times, the heterogeneous ice nucleation ability of oxalic acid dihydrate significantly changed when the particles had been processed in preceding cloud droplet activation steps. Such behaviour was also observed for the second investigated species, namely sodium oxalate. Our experiments address the atmospheric scenario that coating layers of oxalic acid or its salts may be formed by physical and chemical processing on pre-existing particulates such as mineral dust and soot. Given the broad diversity of the observed heterogeneous ice nucleability of the oxalate species, it is not straightforward to predict whether an oxalate coating layer will improve or reduce the ice nucleation ability of the seed aerosol particles.

  12. 21 CFR 524.1610 - Orbifloxacin, mometasone furoate monohydrate, and posaconazole suspension.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Orbifloxacin, mometasone furoate monohydrate, and... DOSAGE FORM NEW ANIMAL DRUGS § 524.1610 Orbifloxacin, mometasone furoate monohydrate, and posaconazole... furoate monohydrate equivalent to 1 mg mometasone furoate, and 1 mg posaconazole. (b) Sponsor. See...

  13. 21 CFR 524.1610 - Orbifloxacin, mometasone furoate monohydrate, and posaconazole suspension.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Orbifloxacin, mometasone furoate monohydrate, and... DOSAGE FORM NEW ANIMAL DRUGS § 524.1610 Orbifloxacin, mometasone furoate monohydrate, and posaconazole... furoate monohydrate equivalent to 1 mg mometasone furoate, and 1 mg posaconazole. (b) Sponsor. See...

  14. 21 CFR 524.1610 - Orbifloxacin, mometasone furoate monohydrate, and posaconazole suspension.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Orbifloxacin, mometasone furoate monohydrate, and... DOSAGE FORM NEW ANIMAL DRUGS § 524.1610 Orbifloxacin, mometasone furoate monohydrate, and posaconazole... furoate monohydrate equivalent to 1 mg mometasone furoate, and 1 mg posaconazole. (b) Sponsor. See...

  15. 21 CFR 524.1610 - Orbifloxacin, mometasone furoate monohydrate, and posaconazole suspension.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Orbifloxacin, mometasone furoate monohydrate, and... DOSAGE FORM NEW ANIMAL DRUGS § 524.1610 Orbifloxacin, mometasone furoate monohydrate, and posaconazole... furoate monohydrate equivalent to 1 mg mometasone furoate, and 1 mg posaconazole. (b) Sponsor. See...

  16. 21 CFR 524.1610 - Orbifloxacin, mometasone furoate monohydrate, and posaconazole suspension.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Orbifloxacin, mometasone furoate monohydrate, and... DOSAGE FORM NEW ANIMAL DRUGS § 524.1610 Orbifloxacin, mometasone furoate monohydrate, and posaconazole... furoate monohydrate equivalent to 1 mg mometasone furoate, and 1 mg posaconazole. (b) Sponsor. See...

  17. The Structure of an Oxalate Oxidoreductase Provides Insight into Microbial 2-Oxoacid Metabolism.

    PubMed

    Gibson, Marcus I; Brignole, Edward J; Pierce, Elizabeth; Can, Mehmet; Ragsdale, Stephen W; Drennan, Catherine L

    2015-07-01

    Thiamine pyrophosphate (TPP), a derivative of vitamin B1, is a versatile and ubiquitous cofactor. When coupled with [4Fe-4S] clusters in microbial 2-oxoacid:ferredoxin oxidoreductases (OFORs), TPP is involved in catalyzing low-potential redox reactions that are important for the synthesis of key metabolites and the reduction of N2, H(+), and CO2. We have determined the high-resolution (2.27 ) crystal structure of the TPP-dependent oxalate oxidoreductase (OOR), an enzyme that allows microbes to grow on oxalate, a widely occurring dicarboxylic acid that is found in soil and freshwater and is responsible for kidney stone disease in humans. OOR catalyzes the anaerobic oxidation of oxalate, harvesting the low-potential electrons for use in anaerobic reduction and fixation of CO2. We compare the OOR structure to that of the only other structurally characterized OFOR family member, pyruvate:ferredoxin oxidoreductase. This side-by-side structural analysis highlights the key similarities and differences that are relevant for the chemistry of this entire class of TPP-utilizing enzymes. PMID:26061898

  18. ADVANCED OXIDATION: OXALATE DECOMPOSITION TESTING WITH OZONE

    SciTech Connect

    Ketusky, E.; Subramanian, K.

    2012-02-29

    At the Savannah River Site (SRS), oxalic acid is currently considered the preferred agent for chemically cleaning the large underground Liquid Radioactive Waste Tanks. It is applied only in the final stages of emptying a tank when generally less than 5,000 kg of waste solids remain, and slurrying based removal methods are no-longer effective. The use of oxalic acid is preferred because of its combined dissolution and chelating properties, as well as the fact that corrosion to the carbon steel tank walls can be controlled. Although oxalic acid is the preferred agent, there are significant potential downstream impacts. Impacts include: (1) Degraded evaporator operation; (2) Resultant oxalate precipitates taking away critically needed operating volume; and (3) Eventual creation of significant volumes of additional feed to salt processing. As an alternative to dealing with the downstream impacts, oxalate decomposition using variations of ozone based Advanced Oxidation Process (AOP) were investigated. In general AOPs use ozone or peroxide and a catalyst to create hydroxyl radicals. Hydroxyl radicals have among the highest oxidation potentials, and are commonly used to decompose organics. Although oxalate is considered among the most difficult organic to decompose, the ability of hydroxyl radicals to decompose oxalate is considered to be well demonstrated. In addition, as AOPs are considered to be 'green' their use enables any net chemical additions to the waste to be minimized. In order to test the ability to decompose the oxalate and determine the decomposition rates, a test rig was designed, where 10 vol% ozone would be educted into a spent oxalic acid decomposition loop, with the loop maintained at 70 C and recirculated at 40L/min. Each of the spent oxalic acid streams would be created from three oxalic acid strikes of an F-area simulant (i.e., Purex = high Fe/Al concentration) and H-area simulant (i.e., H area modified Purex = high Al/Fe concentration) after nearing dissolution equilibrium, and then decomposed to {le} 100 Parts per Million (ppm) oxalate. Since AOP technology largely originated on using ultraviolet (UV) light as a primary catalyst, decomposition of the spent oxalic acid, well exposed to a medium pressure mercury vapor light was considered the benchmark. However, with multi-valent metals already contained in the feed, and maintenance of the UV light a concern; testing was conducted to evaluate the impact from removing the UV light. Using current AOP terminology, the test without the UV light would likely be considered an ozone based, dark, ferrioxalate type, decomposition process. Specifically, as part of the testing, the impacts from the following were investigated: (1) Importance of the UV light on the decomposition rates when decomposing 1 wt% spent oxalic acid; (2) Impact of increasing the oxalic acid strength from 1 to 2.5 wt% on the decomposition rates; and (3) For F-area testing, the advantage of increasing the spent oxalic acid flowrate from 40 L/min (liters/minute) to 50 L/min during decomposition of the 2.5 wt% spent oxalic acid. The results showed that removal of the UV light (from 1 wt% testing) slowed the decomposition rates in both the F & H testing. Specifically, for F-Area Strike 1, the time increased from about 6 hours to 8 hours. In H-Area, the impact was not as significant, with the time required for Strike 1 to be decomposed to less than 100 ppm increasing slightly, from 5.4 to 6.4 hours. For the spent 2.5 wt% oxalic acid decomposition tests (all) without the UV light, the F-area decompositions required approx. 10 to 13 hours, while the corresponding required H-Area decompositions times ranged from 10 to 21 hours. For the 2.5 wt% F-Area sludge, the increased availability of iron likely caused the increased decomposition rates compared to the 1 wt% oxalic acid based tests. In addition, for the F-testing, increasing the recirculation flow rates from 40 liter/minute to 50 liter/minute resulted in an increased decomposition rate, suggesting a better use of ozone.

  19. Non-invasive Differentiation of Kidney Stone Types using X-ray Dark-Field Radiography

    PubMed Central

    Scherer, Kai; Braig, Eva; Willer, Konstantin; Willner, Marian; Fingerle, Alexander A.; Chabior, Michael; Herzen, Julia; Eiber, Matthias; Haller, Bernhard; Straub, Michael; Schneider, Heike; Rummeny, Ernst J.; Noël, Peter B.; Pfeiffer, Franz

    2015-01-01

    Treatment of renal calculi is highly dependent on the chemical composition of the stone in question, which is difficult to determine using standard imaging techniques. The objective of this study is to evaluate the potential of scatter-sensitive X-ray dark-field radiography to differentiate between the most common types of kidney stones in clinical practice. Here, we examine the absorption-to-scattering ratio of 118 extracted kidney stones with a laboratory Talbot-Lau Interferometer. Depending on their chemical composition, microscopic growth structure and morphology the various types of kidney stones show strongly varying, partially opposite contrasts in absorption and dark-field imaging. By assessing the microscopic calculi morphology with high resolution micro-computed tomography measurements, we illustrate the dependence of dark-field signal strength on the respective stone type. Finally, we utilize X-ray dark-field radiography as a non-invasive, highly sensitive (100%) and specific (97%) tool for the differentiation of calcium oxalate, uric acid and mixed types of stones, while additionally improving the detectability of radio-lucent calculi. We prove clinical feasibility of the here proposed method by accurately classifying renal stones, embedded within a fresh pig kidney, using dose-compatible measurements and a quick and simple visual inspection. PMID:25873414

  20. Extracorporeal shock wave lithotripsy: the use of chemical treatments for improved stone comminution.

    PubMed

    Akers, S R; Cocks, F H; Weinerth, J L

    1987-11-01

    Extracorporeal shock wave lithotripsy (ESWL) can require more than two thousand acoustic shocks to achieve an adequate degree of renal calculus comminution. A decrease in the number of shocks necessary for effective treatment offers both technical and clinical benefits. The results presented here demonstrate that it is possible in particular cases to increase substantially the degree of comminution produced using a fixed number of acoustic impulses by exposing the stones to solutions of controlled pH and chemical composition during acoustic shock treatment. The largest increase in comminution was observed for magnesium ammonium phosphate hexahydrate/apatite stones exposed to citrate solutions. The smaller particle sizes are shown to result not only from stone dissolution but also from an increase in the ease of stone fracture during acoustic shocking. The degree of comminution of the largest fragment sizes was also found to be slightly increased for calcium oxalate stones by exposure to synthetic urine of elevated pH. These chemical methods of increased stone comminution appear to be directly applicable to particular cases and may have general clinical utility if suitable conditions affecting all stones can be found. PMID:3669190

  1. 3-Cyanoanilinium hydrogen oxalate hemihydrate

    PubMed Central

    Chen, Xin-Yuan

    2012-01-01

    In the title hydrated molecular salt, C7H7N2 +C2HO4 ?0.5H2O, contains a 3-cyanoanilinium cation, a hydrogen oxalate anion and half a water molecule in an asymmetric unit. The dihedral angle between the CO2(H) and CO2 planes of the hydrogen oxalate ion is 7.96?(1). In the crystal, the components are linked by NH?O and OH?O hydrogen bonds, forming a layer lying parallel to the ac plane. PMID:22719472

  2. Role of Transport and Kinetics in Growth of Renal Stones

    NASA Technical Reports Server (NTRS)

    Kassemi, Mohammad; Iskovitz, Ilana

    2012-01-01

    Renal stone disease is not only a concern on earth but could conceivably pose as a serious risk to the astronauts health and safety in Space. In this paper, a combined transport-kinetics model for growth of calcium oxalate crystals is presented. The model is used to parametrically investigate the growth of renal calculi in urine with a focus on the coupled effects of transport and surface reaction on the ionic concentrations at the surface of the crystal and their impact on the resulting growth rates. It is shown that under nominal conditions of low solution supersaturation and low Damkohler number that typically exist on Earth, the surface concentrations of calcium and oxalate approach their bulk solution values in the urine and the growth rate is most likely limited by the surface reaction kinetics. But for higher solution supersaturations and larger Damkohler numbers that may be prevalent in the microgravity environment of Space, the calcium and oxalate surface concentrations tend to shift more towards their equilibrium or saturation values and thus the growth process may be limited by the transport through the medium. Furthermore, parametric numerical studies suggest that changes to the renal biochemistry of astronauts due in space may promote development of renal calculi during long duration space expeditions.

  3. Diet for Kidney Stone Prevention

    MedlinePLUS

    ... may also help prevent kidney stones, such as citrus drinks. Recommendations based on the specific type of ... do to prevent kidney stones. Some studies suggest citrus drinks like lemonade and orange juice protect against ...

  4. Kidney Stone Treatment with Lithotripsy

    MedlinePLUS Videos and Cool Tools

    Kidney Stone Treatment with Lithotripsy Broward Health Medical Center Fort Lauderdale, FL November 11, 2011 I'm ... got at least three stones in his left kidney. He's been having pain and blood in his ...

  5. Stones and urinary tract infections.

    PubMed

    Miano, Roberto; Germani, Stefano; Vespasiani, Giuseppe

    2007-01-01

    The term infection stones refers to calculi that occur following urinary tract infections (UTIs) caused by urease-producing gram-negative organisms. They consist of magnesium ammonium phosphate, carbonate apatite and monoammonium urate. Alkaline urine is most favorable to their formation. Urinary tract obstruction, neurogenic bladder, voiding dysfunction, temporary or indwelling urinary catheters, distal renal tubular acidosis and medullary sponge kidney are considered the main risk factors for developing infection stones. Urinalysis and urine culture are essential for diagnosis. A typical finding on imaging is a moderately radiopaque, staghorn or branched stone. Curative treatment is possible only by eliminating all of the stone fragments and by eradicating UTI. A variety of operative and pharmaceutical approaches is available. Metaphylactic treatment is mandatory to prevent recurrences. The relationship between urinary stones and UTIs is well known and shows two different clinical pictures: (1) stones that develop following UTIs (infection stones) which play a key role in stone pathogenesis, and (2) stones complicated by UTIs (stones with infection) which are metabolic stones that passively trap bacteria from coexistent UTIs and may consist of calcium or non-calcium. This article presents an overview of infection stones, analyzing the epidemiology, composition, pathogenesis, diagnosis, treatment and prevention of this type of calculi. PMID:17726350

  6. 40 CFR 721.10628 - Mixed metal oxalate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Mixed metal oxalate (generic). 721... Substances § 721.10628 Mixed metal oxalate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as mixed metal oxalate (PMN...

  7. 40 CFR 721.10628 - Mixed metal oxalate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Mixed metal oxalate (generic). 721... Substances § 721.10628 Mixed metal oxalate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as mixed metal oxalate (PMN...

  8. When Stones Teach.

    ERIC Educational Resources Information Center

    Lucier, Todd

    2001-01-01

    Creating towers of balanced stones is a versatile outdoor learning activity that can be experienced in the classroom, school yard, forest, or parking lot. Students discover hidden talents, learn to work and communicate clearly with others, and reconnect with the natural world. Several variations on the exercise are given, along with principles of

  9. When Stones Teach.

    ERIC Educational Resources Information Center

    Lucier, Todd

    2001-01-01

    Creating towers of balanced stones is a versatile outdoor learning activity that can be experienced in the classroom, school yard, forest, or parking lot. Students discover hidden talents, learn to work and communicate clearly with others, and reconnect with the natural world. Several variations on the exercise are given, along with principles of…

  10. Ethylene glycol induces calcium oxalate crystal deposition in Malpighian tubules: a Drosophila model for nephrolithiasis/urolithiasis.

    PubMed

    Chen, Yung-Hsiang; Liu, Hsin-Ping; Chen, Huey-Yi; Tsai, Fuu-Jen; Chang, Chiao-Hui; Lee, Yuan-Ju; Lin, Wei-Yong; Chen, Wen-Chi

    2011-08-01

    Several animal species are used to study calcium oxalate urolithiasis; however, an ideal model has yet to be identified. We used Drosophila as a model organism and fed the flies lithogenic agents such as ethylene glycol, hydroxyl-L-proline, and sodium oxalate. At different times, the Malpighian tubules, the kidney equivalent of insects, were dissected and a polarized light microscope used to highlight the birefringent crystals. Scanning electron microscopy and energy-dispersive X-ray spectroscopy confirmed that the crystal composition was predominately calcium oxalate. Furthermore, administration of potassium citrate successfully reduced the quantity of and modulated the integrity of the ethylene glycol-induced crystals. Thus, the Drosophila model of bio-mineralization produces crystals in the urinary system through many lithogenic agents, permits observation of crystal formation, and is amenable to genetic manipulation. This model may mimic the etiology and clinical manifestations of calcium oxalate stone formation and aid in identification of the genetic basis of this disease. PMID:21451462

  11. Screening of indigenous oxalate degrading lactic acid bacteria from human faeces and South Indian fermented foods: assessment of probiotic potential.

    PubMed

    Gomathi, Sivasamy; Sasikumar, Ponnusamy; Anbazhagan, Kolandaswamy; Sasikumar, Sundaresan; Kavitha, Murugan; Selvi, M S; Selvam, Govindan Sadasivam

    2014-01-01

    Lactic acid bacteria (LAB) have the potential to degrade intestinal oxalate and this is increasingly being studied as a promising probiotic solution to manage kidney stone disease. In this study, oxalate degrading LAB were isolated from human faeces and south Indian fermented foods, subsequently assessed for potential probiotic property in vitro and in vivo. Based on preliminary characteristics, 251 out of 673 bacterial isolates were identified as LAB. A total of 17 strains were found to degrade oxalate significantly between 40.38% and 62.90% and were subjected to acid and bile tolerance test. Among them, nine strains exhibited considerable tolerance up to pH 3.0 and at 0.3% bile. These were identified as Lactobacillus fermentum and Lactobacillus salivarius using 16S rDNA sequencing. Three strains, Lactobacillus fermentum TY5, Lactobacillus fermentum AB1, and Lactobacillus salivarius AB11, exhibited good adhesion to HT-29 cells and strong antimicrobial activity. They also conferred resistance to kanamycin, rifampicin, and ampicillin, but were sensitive to chloramphenicol and erythromycin. The faecal recovery rate of these strains was observed as 15.16% (TY5), 6.71% (AB1), and 9.3% (AB11) which indicates the colonization ability. In conclusion, three efficient oxalate degrading LAB were identified and their safety assessments suggest that they may serve as good probiotic candidates for preventing hyperoxaluria. PMID:24723820

  12. Direct carbothermic reduction of actinide oxalates: Example of Nd(III) oxalate-carbon mixtures conversion

    NASA Astrophysics Data System (ADS)

    Handschuh, A.; Dubois, S.; Vaudez, S.; Grandjean, S.; Leturcq, G.; Abraham, F.

    2009-03-01

    Mixed uranium-plutonium monocarbide was obtained by carbothermic reduction of mixture of UO 2, PuO 2 and C at around 1500 C under vacuum or argon for 4 h followed by sintering at around 1650 C under mixture of Ar + 8%H 2 for 10 h. Moreover, PuO 2 was synthesized by oxalic precipitation followed by calcination at around 700 C (PUREX process). This work deals with a process simplification, i.e. fabrication of carbide by calcination of actinide oxalate, precipitated in presence of carbon, at 1600 C for 13 h under argon. In this preliminary study, neodymium was used as a surrogate of actinides. No carbon influence was noticed during calcination of neodymium oxalate into oxide. Carbon content was the same before and after calcination making possible conversion to carbide directly from mixture of neodymium oxalate and C.

  13. Influence of impurities on the crystallization of dextrose monohydrate

    NASA Astrophysics Data System (ADS)

    Markande, Abhay; Nezzal, Amale; Fitzpatrick, John; Aerts, Luc; Redl, Andreas

    2012-08-01

    The effects of impurities on dextrose monohydrate crystallization were investigated. Crystal nucleation and growth kinetics in the presence of impurities were studied using an in-line focused beam reflectance monitoring (FBRM) technique and an in-line process refractometer. Experimental data were obtained from runs carried out at different impurity levels between 4 and 11 wt% in the high dextrose equivalent (DE) syrup. It was found that impurities have no significant influence on the solubility of dextrose in water. However, impurities have a clear influence on the nucleation and growth kinetics of dextrose monohydrate crystallization. Nucleation and growth rate were favored by low levels of impurities in the syrup.

  14. Aripiprazole salts. III. Bis(aripiprazolium) oxalate-oxalic acid (1/1).

    PubMed

    Freire, Eleonora; Polla, Griselda; Baggio, Ricardo

    2013-02-01

    The asymmetric unit of the title salt [systematic name: bis(4-(2,3-dichlorophenyl)-1-{4-[(2-oxo-1,2,3,4-tetrahydroquinolin-7-yl)oxy]butyl}piperazin-1-ium) oxalate-oxalic acid (1/1)], 2C(23)H(28)Cl(2)N(3)O(2)(+)C(2)O(4)(2-)C(2)H(2)O(4), consists of one protonated aripiprazole unit (HArip(+)), half an oxalate dianion and half an oxalic acid molecule, the latter two lying on inversion centres. The conformation of the HArip(+) cation differs from that in other reported salts and resembles more the conformation of neutral Arip units in reported polymorphs and solvates. The intermolecular interaction linking HArip(+) cations is also similar to those in reported Arip compounds crystallizing in the space group P1, with head-to-head N-HO hydrogen bonds generating centrosymmetric dimers, which are further organized into planar ribbons parallel to (012). The oxalate anions and oxalic acid molecules form hydrogen-bonded chains running along [010], which 'pierce' the planar ribbons, interacting with them through a number of stronger N-HO and weaker C-HO hydrogen bonds, forming a three-dimensional network. PMID:23377689

  15. Effects of water hardness on urinary risk factors for kidney stones in patients with idiopathic nephrolithiasis.

    PubMed

    Bellizzi, V; De Nicola, L; Minutolo, R; Russo, D; Cianciaruso, B; Andreucci, M; Conte, G; Andreucci, V E

    1999-01-01

    Both amount and timing of dietary calcium intake influence the recurrence of renal calcium stones. We have evaluated whether the hardness of extra meal drinking water modifies the risk for calcium stones. The urinary levels of calcium, oxalate and citrate, i.e., the main urinary risk factors for calcium stones, were measured in 18 patients with idiopathic nephrolithiasis, maintained at fixed dietary intake of calcium (800 mg/day), after drinking for 1 week 2 liters per day, between meals, of tap water and at the end of 1 week of the same amount of bottled hard (Ca2+ 255 mg/l) or soft (Ca2+ 22 mg/l, Fiuggi water) water, in a double-blind randomized, crossover fashion. As compared with both tap and soft water, hard water was associated with a significant 50% increase of the urinary calcium concentration in the absence of changes of oxalate excretion; the calcium-citrate index revealed a significant threefold increase during ingestion of hard water as compared with respect to soft water (Fiuggi water), making the latter preferable even when compared with tap water. This study suggests that, in the preventive approach to calcium nephrolithiasis, the extra meal intake of soft water is preferable to hard water, since it is associated with a lower risk for recurrence of calcium stones. PMID:9873217

  16. Economic impact of urinary stones

    PubMed Central

    Hyams, Elias S.

    2014-01-01

    Kidney stones have been rising in prevalence in the United States and worldwide, and represent a significant cost burden. Cost effectiveness research in this area may enable improvements in treatment efficiency that can benefit patients, providers and the healthcare system. There has been limited research in the cost effectiveness of surgical interventions for stone disease, despite the diverse treatment approaches that are available. Medical expulsive therapy (MET) has been shown to improve rates of stone passage for ureteral stones, and there is evidence that this practice should be liberalized from the standpoint of both clinical and cost effectiveness. While conservative treatment following a primary stone event appears to be cost effective, the economic impact of medical therapy for recurrent stone formers requires clarification despite its clinical efficacy. Future study regarding the cost effectiveness of prevention and interventions for stone disease are likely to improve both the quality and efficiency of care. PMID:26816777

  17. Wanted: suitable replacement stones for the Lede stone (Belgium)

    NASA Astrophysics Data System (ADS)

    De Kock, T.; Dewanckele, J.; Boone, M. A.; De Boever, W.; De Schutter, G.; Jacobs, P.; Cnudde, V.

    2012-04-01

    The Lede stone is an arenaceous limestone with a Lutetian age, occurring as discrete (most of the times three) stone banks in the marine sandy sediments of the Lede Formation (Belgium). It has a quartz content of approximate 40%. This increases abrasion strength and together with the cementation results in an average compressive strength of about 80-85 MPa. The cement is a microsparitic calcite cement. Other carbonate particles are both microfossils (mainly foraminifers) and macrofossils (bivalves, serpulids, echinoderms, …). This great diversity gives the stone a heterogeneous, animated appearance. The intra- and interparticle porosity is in total 5-10 % in average and the apparent density is 2400-2550 kg/m3. Another important constituent is glauconite, present in a few percent. In fresh state, the stone has a greenish-grey colour, but when it is exposed to atmospheric conditions for a couple of years, the stone acquires a yellowish to rust-coloured patina due to the weathering of glauconite. Sulphatation causes severe damage to the stone, and black gypsum crusts are common in urban environments on stones protected from runoff. This stone was excavated in both open air and underground quarries in the areas of Brussels and Ghent. The proximity of main rivers such as the Scheldt and Zenne provided transport routes for export towards the north (e.g. Antwerp and The Netherlands). Its first known use dates back to Roman times but the stone flourished in Gothic architecture due to its easy workability and its 'divine' light coloured patina. This results nowadays in a dominant occurrence in the cultural heritage of northwestern Belgium and the south of The Netherlands. Socio-economical reasons caused several declines and revivals of Lede stone in use. In the beginning of the 20th century, only a few excavation sites remained, with as main quarry the one located at Bambrugge (Belgium). By the end of the first half of the 20th century, however, no quarry sites remained. In the sixties, a sand quarry located in Balegem (Belgium) started with the extraction of Lede stone combined with its other activities. Until now, only this site supplies blocks of fresh Lede stones and it doesn't seem there will rise an opportunity of a new site in the near future. Therefore, during the huge amount of renovation works in the past century, the Lede stone was often replaced by imported (mostly French) limestones such as Massangis stone, Savonnières stone and Euville stone. The commercial value seems to have had a large impact and too little attention was paid on the optical appearance, ageing and technical compatibility of the stones. The use of especially Massangis stone was taken for granted. In the 21st century, there is a growing awareness of the impact of such consequent replacement for the historical value of our cultural heritage and several alternative stones are suggested and even used. These include stones from France, Spain and Portugal, but also from other regions in Belgium. For the moment, there is no consensus on the most appropriate replacement stone and further research should be done in order to evaluate compatibility of the different stone types with Lede stone. In this context, it is also very important to actively search for better alternatives, which resemble the Lede stone in both a mechanical and aesthetical point of view. Therefore, this abstract is an open question to its readers. Any commercial natural stone suggestions with affiliation to the aforementioned properties are welcome by e-mailing the corresponding author.

  18. The complexon-renal stone interaction: solubility and electronic microscopy studies.

    PubMed

    Kustov, Andrey V; Berezin, Boris D; Trostin, Vyacheslav N

    2009-07-16

    We have studied how complex formation between calcium and ethylenediaminetetraacetate or citrate ions influences the surface texture and the size of passed oxalate-phosphate renal stones. The four hour concrement treatment by sodium citrate or ethylenediaminetetraacetate aqueous solutions strongly affects the stone texture and provides a mass loss of 6-15%. We have found a significant decrease of the calcium and phosphor content on a concrement surface and formation of appreciable cracks. Our results do indicate that the Ca-complexon interaction can be effectively applied for disrupting some types of renal stones and, especially, residual concrements, which frequently occurs after a surgical operation or an extracorporeal shock-wave lithotripsy. This study provides an additional quantitative physicochemical basis for this slightly invasive therapy. PMID:19537693

  19. From crystalluria to kidney stones, some physicochemical aspects of calcium nephrolithiasis

    PubMed Central

    Baumann, Johannes M; Affolter, Beat

    2014-01-01

    Nephrolithiasis seems to be the result of crystal formation, aggregation and retention in the kidney during crystalluria. These processes have to occur within the short urinary transit time through the kidney being in the order of few minutes. Recently much work was done on rather qualitative aspects of nephrolithiasis like genetics, metabolism and morphology. In this review we try to provide some quantitative information on urinary supersaturation with respect to stone minerals, especially Ca oxalate (CaOx), on the formation and aggregation of CaOx crystals and on crystal retention in the kidney. The paper is centered on idiopathic Ca nephrolithiasis being the most frequent stone disease with only partially known pathogenesis. New aspects of the role of urinary macromolecules in stone formation and of the mechanism of crystal aggregation are provided. PMID:25374820

  20. Invasive urothelial carcinoma within a calyceal diverticulum associated with renal stones: A case report

    PubMed Central

    NAKANO, TAITO; KITAGAWA, YASUHIDE; IZUMI, KOUJI; IKEDA, HIROKO; NAMIKI, MIKIO

    2015-01-01

    Calyceal diverticula are rare outpouchings of the upper collecting system lying within the renal parenchyma. These often contain stones, however, carcinoma within a calyceal diverticulum is uncommon. The present study reports a case of invasive urothelial carcinoma within a calyceal diverticulum associated with renal stones. A 70-year-old male with a left renal mass identified by abdominal computed tomography was referred to the Department of Urology, Kanazawa University Hospital. Pre-operative diagnosis was difficult owing to an atypical imaging finding of a hypovascular renal mass with calcification. A laparoscopic nephroureterectomy was performed, and the surgical specimens showed invasive high-grade urothelial carcinoma within a calyceal diverticulum, and the calcifications were renal stones consisting of 97% calcium oxalate. Urothelial carcinoma in calyceal diverticula is a rare condition, however, a pre-operative definite diagnosis is difficult and a high potential for invasion of the renal parenchyma is suspected in this disease. PMID:26622866

  1. Complicated bile duct stones

    PubMed Central

    Roy, Ashwin; Martin, Derrick

    2013-01-01

    Common bile duct stones (CBDSs) are solid deposits that can either form within the gallbladder or migrate to the common bile duct (CBD), or form de novo in the biliary tree. In the USA around 15% of the population have gallstones and of these, 3% present with symptoms annually. Because of this, there have been major advancements in the management of gallstones and related conditions. Management is based on the patient's risk profile; young and healthy patients are likely to be recommended for surgery and elderly patients with comorbidities are usually recommended for endoscopic procedures. Imaging of gallstones has advanced in the last 30 years with endoscopic retrograde cholangiopancreatography evolving from a diagnostic to a therapeutic procedure in removing CBDSs. We present a complicated case of a patient with a CBDS and periampullary diverticulum and discuss the techniques used to diagnose and remove the stone from the biliary system. PMID:23946532

  2. Use of Potassium Citrate to Reduce the Risk of Renal Stone Formation During Spaceflight

    NASA Technical Reports Server (NTRS)

    Whitson, P. A.; Pietrzyk, R. A.; Sams, C. F.; Jones, J. A.; Nelman-Gonzalez, M.; Hudson, E. K.

    2008-01-01

    Introduction: NASA s Vision for Space Exploration centers on exploration class missions including the goals of returning to the moon and landing on Mars. One of NASA s objectives is to focus research on astronaut health and the development of countermeasures that will protect crewmembers during long duration voyages. Exposure to microgravity affects human physiology and results in changes in the urinary chemical composition favoring urinary supersaturation and an increased risk of stone formation. Nephrolithiasis is a multifactorial disease and development of a renal stone is significantly influenced by both dietary and environmental factors. Previous results from long duration Mir and short duration Shuttle missions have shown decreased urine volume, pH, and citrate levels and increased calcium. Citrate, an important inhibitor of calcium-containing stones, binds with urinary calcium reducing the amount of calcium available to form stones. Citrate inhibits renal stone recurrence by preventing crystal growth, aggregation, and nucleation and is one of the most common therapeutic agents used to prevent stone formation. Methods: Thirty long duration crewmembers (29 male, 1 female) participated in this study. 24-hour urines were collected and dietary monitoring was performed pre, in, and postflight. Crewmembers in the treatment group received two potassium citrate (KCIT) pills, 10 mEq/pill, ingested daily beginning 3 days before launch, all inflight days and through 14 days postflight. Urinary biochemical and dietary analyses were completed. Results: KCIT treated subjects exhibited decreased urinary calcium excretion and maintained the levels of calcium oxalate supersaturation risk at their preflight levels. The increased urinary pH levels in these subjects reduced the risk of uric acid stones. Discussion: The current study investigated the use of potassium citrate as a countermeasure to minimize the risk of stone formation during ISS missions. Results suggest that supplementation with potassium citrate decreases the risk of stone formation during and immediately after spaceflight.

  3. Effect of Renal Insufficiency on Stone Recurrence in Patients with Urolithiasis

    PubMed Central

    2014-01-01

    The study was designed to assess the relationship between glomerular filtration rate (GFR) and urinary stone-forming constituents, and to assess the effect of renal insufficiency on stone recurrence risk in first stone formers (SF). Baseline serum creatinine levels were obtained, and renal insufficiency was defined as creatinine clearance ?60 mL/min (Cockroft-Gault). This retrospective case-control study consists of 342 first SF; 171 SF with normal renal function were selected with 1:1 propensity scores matched to 171 SF with renal insufficiency. Urinary metabolic evaluation was compared to renal function. GFR was positively correlated with urinary calcium, uric acid, and citrate excretion. Subjects with renal insufficiency had significantly lower urinary calcium, uric acid, and citrate excretion than those with normal renal function, but not urine volume. With regard to urinary metabolic abnormalities, similar results were obtained. SF with renal insufficiency had lower calcium oxalate supersaturation indexes and stone recurrence rates than SF with normal renal function. Kaplan-Meier curves showed similar results. In conclusion, GFR correlates positively with urinary excretion of stone-forming constituents in SF. This finding implies that renal insufficiency is not a risk factor for stone recurrence. Graphical Abstract PMID:25120325

  4. Effect of renal insufficiency on stone recurrence in patients with urolithiasis.

    PubMed

    Kang, Ho Won; Seo, Sung Phil; Kim, Won Tae; Kim, Yong-June; Yun, Seok-Joong; Lee, Sang-Cheol; Kim, Wun-Jae

    2014-08-01

    The study was designed to assess the relationship between glomerular filtration rate (GFR) and urinary stone-forming constituents, and to assess the effect of renal insufficiency on stone recurrence risk in first stone formers (SF). Baseline serum creatinine levels were obtained, and renal insufficiency was defined as creatinine clearance ≤60 mL/min (Cockroft-Gault). This retrospective case-control study consists of 342 first SF; 171 SF with normal renal function were selected with 1:1 propensity scores matched to 171 SF with renal insufficiency. Urinary metabolic evaluation was compared to renal function. GFR was positively correlated with urinary calcium, uric acid, and citrate excretion. Subjects with renal insufficiency had significantly lower urinary calcium, uric acid, and citrate excretion than those with normal renal function, but not urine volume. With regard to urinary metabolic abnormalities, similar results were obtained. SF with renal insufficiency had lower calcium oxalate supersaturation indexes and stone recurrence rates than SF with normal renal function. Kaplan-Meier curves showed similar results. In conclusion, GFR correlates positively with urinary excretion of stone-forming constituents in SF. This finding implies that renal insufficiency is not a risk factor for stone recurrence. PMID:25120325

  5. Pyrophosphate Transport and Stones

    NASA Astrophysics Data System (ADS)

    Sayer, John A.; Carr, Georgina; Moochhala, Shabbir H.; Simmons, Nicholas L.

    2008-09-01

    Since the 1960's, inorganic pyrophosphate (PPi) has been known to inhibit apatite precipitation. Recent findings suggest that PPi plays a central role in the control of normal bone mineralization. Knockout mice have established the functional importance of PPi transmembrane transport, via the pyrophosphate transporter ANKH. The molecular nature and transport function of ANKH are reviewed. PPi is present in urine and ANKH is expressed in the cortical collecting duct where PPi transport to both the tubular lumen and renal interstitium may occur. Arginine vasopressin stimulation of cortical collecting duct cells grown on semi-permeable supports appears to upregulate apical ANKH expression, which we postulate may be a mechanism of stone inhibition during urinary concentration and supersaturation of calcium salts. Hypopyrophosphaturia may be a forgotten metabolic risk factor for stone formation and polymorphisms of the ANKH gene may underlie this defect. The physiological importance and clinical significance of PPi generation and transport in preventing idiopathic renal stone disease and nephrocalcinosis now needs to be established.

  6. Phosphorylation of osteopontin peptides mediates adsorption to and incorporation into calcium oxalate crystals.

    PubMed

    O'Young, Jason; Chirico, Sara; Al Tarhuni, Nehal; Grohe, Bernd; Karttunen, Mikko; Goldberg, Harvey A; Hunter, Graeme K

    2009-01-01

    Phosphorylated peptides of osteopontin (OPN) have been shown to inhibit the growth of the {100} face of calcium oxalate monohydrate (COM). The inhibitory potency has been shown to be dependent on the phosphate content of the peptide. The purpose of this study is to better understand the means by which phosphate groups promote crystal growth inhibition by OPN peptides. Peptides of rat bone OPN 220-235 peptides have been synthesized with zero (P0), 1 (P1) or 3 (P3) phosphate modifications. COM crystals were grown in the presence of 0.1-10 microg of P0, P1 or P3. P0 incorporation into COM crystals was evident at 10 microg/ml of peptide, whereas the phosphorylated peptides P1 and P3 were incorporated at all tested concentrations. At 5 microg/ml of P3, COM crystals exhibited a 'dumbbell' morphology. To study the peptide-mineral interaction, surface frequency plots were constructed from molecular dynamics simulations of OPN peptide adsorption. Carboxylate and phosphate groups were found to adsorb in specific orientations to the COM {100} surface. In conclusion, it appears that the phosphate groups on OPN peptides are capable of interacting with the COM {100} surface. This interaction appears to increase the adsorption energy of the peptide to the surface, thus enhancing its inhibitory potency. PMID:18728346

  7. Mode of Action: Oxalate Crystal-Induced Renal Tubule Degeneration and Glycolic Acid-Induced Dysmorphogenesis—Renal and Developmental Effects of Ethylene Glycol

    SciTech Connect

    Corley, Rick A.; Meek, M E.; Carney, E W.

    2005-10-01

    Ethylene glycol can cause both renal and developmental toxicity, with metabolism playing a key role in the mode of action (MOA) for each form of toxicity. Renal toxicity is ascribed to the terminal metabolite oxalic acid, which precipitates in the kidney in the form of calcium oxalate crystals and is believed to cause physical damage to the renal tubules. The human relevance of the renal toxicity of ethylene glycol is indicated by the similarity between animals and humans of metabolic pathways, the observation of renal oxalate crystals in toxicity studies in experimental animals and human poisonings, and cases of human kidney and bladder stones related to dietary oxalates and oxalate precursors. High-dose gavage exposures to ethylene glycol also cause axial skeletal defects in rodents (but not rabbits), with the intermediary metabolite, glycolic acid, identified as the causative agent. However, the mechanism by which glycolic acid perturbs development has not been investigated sufficiently to develop a plausible hypothesis of mode of action, nor have any cases of ethylene glycol-induced developmental effects been reported in humans. Given this, and the variations in sensitivity between animal species in response, the relevance to humans of ethylene glycol-induced developmental toxicity in animals is unknown at this time.

  8. Red facts: Oxalic acid. Fact sheet

    SciTech Connect

    Not Available

    1992-12-01

    All pesticides sold or used in the United States must be registered by EPA, based on scientific studies showing that they can be used without posing unreasonable risks to people or the environment. Because of advances in scientific knowledge, the law requires that pesticides which were first registered years ago be reregistered to ensure that they meet today's more stringent standards. Oxalic acid is registered for use as a disinfectant to control bacteria and germs, and as a sanitizer, in toilet bowls, urinals and bathroom premises. Oxalic acid also has many diverse, non-pesticidal, manufacturing and industrial uses including use in fabric printing and dyeing; bleaching straw hats; removing paint, varnish, rust or ink stains; and cleaning wood.

  9. OXALATE MASS BALANCE DURING CHEMICAL CLEANING IN TANK 6F

    SciTech Connect

    Poirier, M.; Fink, S.

    2011-07-22

    The Savannah River Remediation (SRR) is preparing Tank 6F for closure. The first step in preparing the tank for closure is mechanical sludge removal. Following mechanical sludge removal, SRS performed chemical cleaning with oxalic acid to remove the sludge heel. Personnel are currently assessing the effectiveness of the chemical cleaning to determine whether the tank is ready for closure. SRR personnel collected liquid samples during chemical cleaning and submitted them to Savannah River National Laboratory (SRNL) for analysis. Following chemical cleaning, they collected a solid sample (also known as 'process sample') and submitted it to SRNL for analysis. The authors analyzed these samples to assess the effectiveness of the chemical cleaning process. Analysis of the anions showed the measured oxalate removed from Tank 6F to be approximately 50% of the amount added in the oxalic acid. To close the oxalate mass balance, the author collected solid samples, leached them with nitric acid, and measured the concentration of cations and anions in the leachate. Some conclusions from this work are: (1) Approximately 65% of the oxalate added as oxalic acid was removed with the decanted liquid. (2) Approximately 1% of the oxalate (added to the tank as oxalic acid) formed precipitates with compounds such as nickel, manganese, sodium, and iron (II), and was dissolved with nitric acid. (3) As much as 30% of the oxalate may have decomposed forming carbon dioxide. The balance does not fully account for all the oxalate added. The offset represents the combined uncertainty in the analyses and sampling.

  10. Medical management of renal stones.

    PubMed

    Morgan, Monica S C; Pearle, Margaret S

    2016-01-01

    The prevalence of kidney stones is increasing in industrialized nations, resulting in a corresponding rise in economic burden. Nephrolithiasis is now recognized as both a chronic and systemic condition, which further underscores the impact of the disease. Diet and environment play an important role in stone disease, presumably by modulating urine composition. Dietary modification as a preventive treatment to decrease lithogenic risk factors and prevent stone recurrence has gained interest because of its potential to be safer and more economical than drug treatment. However, not all abnormalities are likely to be amenable to dietary therapy, and in some cases drugs are necessary to reduce the risk of stone formation. Unfortunately, no new drugs have been developed for stone prevention since the 1980s when potassium citrate was introduced, perhaps because the long observation period needed to demonstrate efficacy discourages investigators from embarking on clinical trials. Nonetheless, effective established treatment regimens are currently available for stone prevention. PMID:26977089

  11. Villamayor stone (Golden Stone) as a Global Heritage Stone Resource from Salamanca (NW of Spain)

    NASA Astrophysics Data System (ADS)

    Garcia-Talegon, Jacinta; Iñigo, Adolfo; Vicente-Tavera, Santiago

    2013-04-01

    Villamayor stone is an arkosic stone of Middle Eocene age and belongs to the Cabrerizos Sandstone Formation that comprising braided fluvial systems and paleosoils at the top of each stratigraphic sequence. The sandstone is known by several names: i) the Villamayor Stone because the quarries are located in Villamayor de Armuña village that are situated at 7 km to the North from Salamanca city; ii) the Golden Stone due to its patina that produced a ochreous/golden color on the façades of monuments of Salamanca (World Heritage City,1988) built in this Natural stone (one of the silicated rocks utilised). We present in this work, the Villamayor Stone to be candidate as Global Heritage Stone Resource. The Villamayor Stone were quarrying for the construction and ornamentation of Romanesque religious monuments as the Old Cathedral and San Julian church; Gothic (Spanish plateresc style) as the New Cathedral, San Esteban church and the sculpted façade of the Salamanca University, one of the oldest University in Europe (it had established in 1250); and this stone was one of the type of one of the most sumptuous Baroque monuments is the Main Square of the its galleries and arcades (1729). Also, this stone was used in building palaces, walls and reconstruction of Roman bridge. Currently, Villamayor Stone is being quarried by small and family companies, without a modernized processing, for cladding of the façades of the new buildings until that the construction sector was burst (in 2008 the international economic crisis). However, Villamayor Stone is the main stone material used in the city of Salamanca for the restoration of monuments and, even in small quantities when compared with just before the economic crisis, it would be of great importance for future generations protect their quarries and the craft of masonry. Villamayor Stone has several varieties from channels facies to floodplains facies, in this work the selected varieties are: i) the fine-grained stone, microporous, is partially cemented by dolomite, 27% (bulk porosity), ii) the ochre and fine-grained stone, microporous, with smectite, 30% (bulk porosity), iii) the medium-grained stone, 38% (bulk porosity). Main components for all three varieties: Quartz (up to 60%), feldspars, 2:1 layered silicates (smectites), palygorskite-type fibrous silicates, and small amounts of micaceous minerals (illite/mica).

  12. The Systematic Classification of Gallbladder Stones

    PubMed Central

    Qiao, Tie; Ma, Rui-hong; Luo, Xiao-bing; Yang, Liu-qing; Luo, Zhen-liang; Zheng, Pei-ming

    2013-01-01

    Background To develop a method for systematic classification of gallbladder stones, analyze the clinical characteristics of each type of stone and provide a theoretical basis for the study of the formation mechanism of different types of gallbladder stones. Methodology A total of 807 consecutive patients with gallbladder stones were enrolled and their gallstones were studied. The material composition of gallbladder stones was analyzed using Fourier Transform Infrared spectroscopy and the distribution and microstructure of material components was observed with Scanning Electron Microscopy. The composition and distribution of elements were analyzed by an X-ray energy spectrometer. Gallbladder stones were classified accordingly, and then, gender, age, medical history and BMI of patients with each type of stone were analyzed. Principal Findings Gallbladder stones were classified into 8 types and more than ten subtypes, including cholesterol stones (297), pigment stones (217), calcium carbonate stones (139), phosphate stones (12), calcium stearate stones (9), protein stones (3), cystine stones (1) and mixed stones (129). Mixed stones were those stones with two or more than two kinds of material components and the content of each component was similar. A total of 11 subtypes of mixed stones were found in this study. Patients with cholesterol stones were mainly female between the ages of 30 and 50, with higher BMI and shorter medical history than patients with pigment stones (P<0.05), however, patients with pigment, calcium carbonate, phosphate stones were mainly male between the ages of 40 and 60. Conclusion The systematic classification of gallbladder stones indicates that different types of stones have different characteristics in terms of the microstructure, elemental composition and distribution, providing an important basis for the mechanistic study of gallbladder stones. PMID:24124459

  13. Growth Conditions To Reduce Oxalic Acid Content of Spinach

    NASA Technical Reports Server (NTRS)

    Johnson-Rutzke, Corinne

    2003-01-01

    A controlled-environment agricultural (CEA) technique to increase the nutritive value of spinach has been developed. This technique makes it possible to reduce the concentration of oxalic acid in spinach leaves. It is desirable to reduce the oxalic acid content because oxalic acid acts as an anti-nutritive calcium-binding component. More than 30 years ago, an enzyme (an oxidase) that breaks down oxalic acid into CO2 and H2O2 was discovered and found to be naturally present in spinach leaves. However, nitrate, which can also be present because of the use of common nitratebased fertilizers, inactivates the enzyme. In the CEA technique, one cuts off the supply of nitrate and keeps the spinach plants cool while providing sufficient oxygen. This technique provides the precise environment that enables the enzyme to naturally break down oxalate. The result of application of this technique is that the oxalate content is reduced by 2/3 in one week.

  14. Our Modern Stone Age

    NASA Astrophysics Data System (ADS)

    Lowry, W. D.

    Unlike most books dealing with industrial minerals and rocks, Our Modern Stone Age is a pleasure to read. Within a matter of several hours, one can get an excellent introduction to nonmetallic mineral resources and industries exclusive o f the mineral fuels. The book is very well written and well illustrated with photographs and drawings; although pitched for the intelligent layman, it is in no way dull reading for even a well-versed economic geologist. Nearly every geologist, mining engineer, mineral economist, planner, and politician will find points of interest in this book.

  15. Synthesis, characterization and DFT-modeling of novel agents for the protection and restoration of historical calcareous stone substrates.

    PubMed

    Maiore, Laura; Aragoni, M Carla; Carcangiu, Gianfranco; Cocco, Ombretta; Isaia, Francesco; Lippolis, Vito; Meloni, Paola; Murru, Arianna; Tuveri, Enrica; Arca, Massimiliano

    2015-06-15

    The ammonium salts of oxamate (AmOxam) and monomethyloxalate (AmMeox), structurally related to ammonium oxalate (AmOx), were synthesized and characterized as protecting agents/filler for calcareous stone substrates. Both compounds featured an improved solubility in water and alcoholic-water mixtures with respect to AmOx. While AmOxam is stable in aqueous solution and reacts with calcite to afford the corresponding insoluble calcium oxamate (CaOxam), AmMeox spontaneously undergoes hydrolysis to give ammonium monohydrogen oxalate hemihydrate (AmBiox) and calcium oxalate (CaOx). Both compounds have been tested for the restoration of naturally weathered marble and biomicritic limestone. The formation of a superficial layer of CaOxam and CaOx was observed on stone samples treated with AmOxam and AmMeox, respectively, depending on the solvent mixture. A quantum-mechanical study was carried out at DFT level in order to investigate the nature of the interactions occurring between the lithic substrate (calcite) and the passivating agents, showing how the structural modifications on oxalic acid derivatives can be exploited to fine-tune their interaction with the calcite surface. PMID:25746185

  16. Temporal changes in the expression of mRNA of NADPH oxidase subunits in renal epithelial cells exposed to oxalate or calcium oxalate crystals

    PubMed Central

    Khan, Saeed R.; Khan, Aslam; Byer, Karen J.

    2011-01-01

    Background. Exposure of renal epithelial cells to oxalate (Ox) or calcium oxalate (CaOx) crystals leads to the production of reactive oxygen species and cell injury. We have hypothesized that Ox and CaOx crystals activate NADPH oxidase through upregulation of its various subunits. Methods. Human renal epithelial-derived cell line, HK-2, was exposed to 100 μmol Ox or 66.7 μg/cm2 CaOx monohydrate crystals for 6, 12, 24 or 48 h. After exposure, the cells and media were processed to determine activation of NADPH oxidase, production of superoxide and 8-isoprostane (8IP), and release of lactate dehydrogenase (LDH). RT-PCR was performed to determine mRNA expression of NADPH subunits p22phox, p40phox, p47phox, p67phox and gp91phox as well as Rac-GTPase. Results. Exposure to Ox and CaOx crystals resulted in increase in LDH release, production of 8-IP, NADPH oxidase activity and production of superoxide. Exposure to CaOx crystals resulted in significantly higher NADPH oxidase activity, production of superoxide and LDH release than Ox exposure. Exposure to Ox and CaOx crystals altered the expression of various subunits of NADPH oxidase. More consistent were increases in the expression of membrane-bound p22phox and cytosolic p47phox. Significant and strong correlations were seen between NADPH oxidase activity, the expression of p22phox and p47phox, production of superoxide and release of LDH when cells were exposed to CaOx crystals. The expressions of neither p22phox nor p47phox were significantly correlated with increased NADPH oxidase activity after the Ox exposure. Conclusions. As hypothesized, exposure to Ox or CaOx crystals leads to significant increases in the expression of p22phox and p47phox, leading to activation of NADPH oxidase. Increased NADPH oxidase activity is associated with increased superoxide production and lipid peroxidation. Different pathways appear to be involved in the stimulation of renal epithelial cells by exposure to Ox and CaOx crystals. PMID:21079197

  17. Mechanistic insight into the evaporative crystallization of two polymorphs of nitrofurantoin monohydrate

    NASA Astrophysics Data System (ADS)

    Tian, F.; Qu, H.; Louhi-Kultanen, M.; Rantanen, J.

    2009-04-01

    This study was conducted to gain a deeper understanding of the crystallization behavior of both known nitrofurantoin (NF) monohydrates (monohydrates I and II). NF monohydrate crystals were obtained by evaporative crystallization from a series of acetone-water mixtures. The water activity of each solution together with the solubility of NF was used for calculation of the NF supersaturation profiles during evaporative crystallization. The crystallization process for each solution was monitored in situ by optical and Raman microscopy. It was found that the fraction of the metastable monohydrate I in the final product increased with decreasing water fraction, suggesting that the nucleation rate of monohydrate I increases with decreasing water activity. In addition, the morphology of both monohydrate forms was affected by the water fraction in the solvent. The in situ images and Raman spectra taken during the evaporative crystallization from water-acetone mixture (0.67 mole fraction of water) demonstrated that the crystallization of the stable monohydrate II was encountered first, and the nucleation of the metastable monohydrate I happened afterwards at a reduced supersaturation level. This indicates that the crystal packing of the NF monohydrate from acetone-water solutions was affected by both supersaturation and water activity.

  18. Calcium oxalate crystal formation in patients with hyperparathyroidism and hyperthyroidism and related metabolic disturbances.

    PubMed

    Kohri, K; Kodama, M; Umekawa, T; Ishikawa, Y; Katayama, Y; Takada, M; Katoh, Y; Kataoka, K; Iguchi, M; Kurita, T

    1990-01-01

    The crystallization of calcium oxalate in the urine of patients with hyperparathyroidism and hyperthyroidism was studied using a mixed suspension mixed product removal (MSMPR) system. In addition, calcium metabolism in hyperthyroidism and its relationship to urolithiasis was investigated. The urines from all the three groups (normal subjects, hyperparathyroid and hyperthyroid patients) showed reduced nucleation rates and increased growth rates in comparison with the control synthetic urine. The nucleation rate was not significantly different between the three human urine groups, while the growth rate was significantly higher in the hyperparathyroid group compared to the normal and hyperthyroid groups. Crystal volume (suspension density) in the hyperparathyroid group was approximately twice that in the other two groups. Serum and ionized calcium levels in hyperparathyroid patients were higher than in normal subjects, while hyperthyroid patients had levels only slightly higher than those in normal subjects. The hyperparathyroid and hyperthyroid groups differed significantly from the normal group in urinary calcium excretion. These two groups also showed significantly higher levels of serum alkaline phosphatase and urinary hydroxyproline than did the normal group. Although hyperthyroid patients have a calcium metabolism similar to hyperparathyroid patients, the incidence of urolithiasis is no different between hyperthyroid and normal subjects. The results of both crystallization and calcium metabolism in hyperparathyroid patients were not significantly different between those with and without urolithiasis. The result of crystallization was also not significantly different between hyperparathyroid patients with and without hypercalciuria. This study suggests that hypercalciuria alone does not produce urinary stones and that urine from hyperparathyroid patients may contain promotors of calcium oxalate crystallization and calcium stone formation. PMID:2306555

  19. The oxalic acid: 2-chloroacetamide crystallization: A new revelation

    NASA Astrophysics Data System (ADS)

    Chitra, R.; Choudhury, R. R.; Capet, Frederic; Roussel, Pascal

    2013-02-01

    The OH of COOH can acts as both donor and acceptor of hydrogen bond. OH of COOH as an acceptor was primarily observed in Oxalic acid Amide complexes. In order to further understand the packing in these complexes, oxalic acid was complexed with 2-tricholoroacetamide. This crystallization resulted in the formation of ammonium tetraoxalate dehydrate. A result similar to what was observed in complexation of oxalic acid with amide containing amino acids (asparagine and glutamine). Interestingly in all these cases, the amide bond is broken, to form the ammonium ion when trying to complex with oxalic acid.

  20. Electrochemical synthesis and characterization of zinc oxalate nanoparticles

    SciTech Connect

    Shamsipur, Mojtaba; Roushani, Mahmoud; Pourmortazavi, Seied Mahdi

    2013-03-15

    Highlights: ? Synthesis of zinc oxalate nanoparticles via electrolysis of a zinc plate anode in sodium oxalate solutions. ? Design of a Taguchi orthogonal array to identify the optimal experimental conditions. ? Controlling the size and shape of particles via applied voltage and oxalate concentration. ? Characterization of zinc oxalate nanoparticles by SEM, UVvis, FT-IR and TGDTA. - Abstract: A rapid, clean and simple electrodeposition method was designed for the synthesis of zinc oxalate nanoparticles. Zinc oxalate nanoparticles in different size and shapes were electrodeposited by electrolysis of a zinc plate anode in sodium oxalate aqueous solutions. It was found that the size and shape of the product could be tuned by electrolysis voltage, oxalate ion concentration, and stirring rate of electrolyte solution. A Taguchi orthogonal array design was designed to identify the optimal experimental conditions. The morphological characterization of the product was carried out by scanning electron microscopy. UVvis and FT-IR spectroscopies were also used to characterize the electrodeposited nanoparticles. The TGDTA studies of the nanoparticles indicated that the main thermal degradation occurs in two steps over a temperature range of 350430 C. In contrast to the existing methods, the present study describes a process which can be easily scaled up for the production of nano-sized zinc oxalate powder.

  1. Scottish Short Stone Rows

    NASA Astrophysics Data System (ADS)

    Ruggles, Clive L. N.

    Short stone rows received a good deal of attention during the 1980s and 1990s, at a time when archaeoastronomy in prehistoric Britain and Ireland was moving beyond reassessments of Alexander Thom's "megalithic observatories" by identifying coherent groups of similar monuments with clear orientation trends. Many such rows are found in western Scotland, with the main concentration in Argyll and the island of Mull. Systematic analyses of their orientations produced credible evidence of an awareness of the 18.6-year lunar node cycle, within a "primary-secondary" pattern whereby isolated rows were oriented close to moonrise or moonset at the southern major standstill limit, while others oriented in this way were accompanied by a second row oriented in a declination range that could be interpreted either as lunar or solar. A detailed investigation of the landscape situation of the sites in northern Mull, accompanied by excavations at two of the sites, suggested that they were deliberately placed in locations where critical moonsets would be seen against prominent distant landscape features, but where the distant horizon in most or all other directions was hidden from view. A lack of independent archaeological evidence may help to explain why archaeoastronomical investigations at short stone rows have never progressed beyond "data-driven" studies of orientations and landscape situation. Nonetheless, the work that was done at these sites raised important general methodological issues, and pioneered techniques, that remain relevant across archaeoastronomy today.

  2. Recumbent Stone Circles

    NASA Astrophysics Data System (ADS)

    Ruggles, Clive L. N.

    During the 1970s and early 1980s, British archaeoastronomers were striving to bridge the interpretative gulf between the "megalithic observatories" of Alexander Thom and an archaeological mainstream that, generally speaking, was hostile to any mention of astronomy in relation to the megalithic monuments of Neolithic and Early Bronze Age Britain. The Scottish recumbent stone circles (RSCs) came to represent an example where sounder methodology could overcome many of the data selection issues that had beset earlier studies and, with due restraint, produce credible interpretations. Systematic studies of their orientations consistently concluded that the RSCs had a strong lunar connection, and it was widely envisaged that they were the setting for ceremonies associated with the appearance of the moon over the recumbent stone. Other evidence such as the presence of white quartz and the spatial distribution of cupmarks appeared to back up this conclusion. New archaeological investigations since 1999 have challenged and modified these conclusions, confirming in particular that the circles were built to enclose cairns rather than to demarcate open spaces. Yet the restricted pattern of orientations of these structures could only have been achieved by reference to the basic diurnal motions of the skies, and orientation in relation to simple observations of the midsummer moon remains the most likely reading of the alignment evidence taken as a whole. On the other hand, a consideration of the broader context, which includes the nearby Clava cairns, highlights instead the symbolic importance of the sun.

  3. Treatment of urinary tract stones.

    PubMed Central

    Wickham, J E

    1993-01-01

    Replacement of open surgery with minimally invasive techniques for treating stones in the renal tract has greatly reduced patients' morbidity and mortality and the period of hospitalisation and convalescence. Extracorporeal shockwave lithotripsy does not require anaesthesia and requires little analgesia so that treatment can be given on an outpatient basis, and there is no wound to heal. Only a small puncture site is needed for percutaneous endoscopic lithotomy, and with the advent of prophylactic antibiotics there are few complications. Of renal stones, about 85% can now be successfully treated by extracorporeal lithotripsy alone, and almost all of the stones too large or hard for lithotripsy can be treated endoscopically, with ultrasonic or electrohydraulic probes being used to fragment the stone. Stones in the upper and lower thirds of the ureter can be treated by extracorporeal lithotripsy, but stones in the middle third, which cannot normally be visualised to allow focusing of the shockwaves, usually require ureteroscopy. Nearly all bladder stones can be treated by transurethral endoscopy with an electrohydraulic probe. Only the largest renal tract stones still require open surgery. Images FIG 10 p1415-a p1415-b p1416-a p1416-b p1417-a PMID:8274898

  4. The exposome for kidney stones.

    PubMed

    Goldfarb, David S

    2016-02-01

    The exposome is the assembly and measure of all the exposures of an individual in a lifetime. An individual's exposures begin before birth and include insults from environmental and occupational sources. The associated field is called exposomics, which relies on the application of internal and external exposure assessment methods. Exposomics has not yet been thoroughly applied to the study of kidney stones although much is known about how diet and fluid intake affect nephrolithiasis. Some other novel exposures that may contribute to kidney stones are discussed including use of antibiotics, urbanization and migration to urban heat islands, and occupation. People whose school and jobs limit their access to fluids and adequate bathroom facilities may have higher prevalence of stones. Examples include athletes, teachers, heathcare workers, and cab drivers. Occupational kidney stones have received scant attention and may represent a neglected, and preventable, type of stone. An exposomic-oriented history would include a careful delineation of occupation and activities. PMID:26615595

  5. Metal Dependence of Oxalate Decarboxylase Activity

    PubMed Central

    Moomaw, Ellen W.; Angerhofer, Alexander; Moussatche, Patricia; Ozarowski, Andrew; Garca-Rubio, Ins; Richards, Nigel G. J.

    2009-01-01

    Bacillus subtilis oxalate decarboxylase (OxDC) catalyzes the conversion of oxalate into CO2 and formate. The enzyme is composed of two cupin domains, each of which contains a Mn(II) ion. Although there is general agreement that Mn(II) in the N-terminal domain mediates OxDC-catalyzed decarboxylation, legitimate questions have been raised concerning the function (if any) of the Mn(II) bound in the C-terminal cupin domain. We have investigated this problem using a series of OxDC mutants in which Mn(II) binding is perturbed by mutagenesis of Glu-101 and Glu-280, which coordinate the metal in the N-terminal and C-terminal domains, respectively. We now demonstrate that decarboxylase activity and total manganese content are sensitive to modifications in either metal-binding glutamate residue. These findings, in combination with EPR measurements, raise the possibility that the C-terminal Mn(II) center can catalyze the decarboxylation reaction. Further support for this conclusion has been provided from a combination of in vivo and in vitro strategies for preparing wild-type OxDC in which Mn(II) is incorporated to a variety of extents. Kinetic characterization of these variants shows that OxDC activity is linearly correlated with manganese content, as might be expected if both sites can catalyze the breakdown of oxalate into formate and CO2. These studies also represent the first unequivocal demonstration that OxDC activity is uniquely mediated by manganese. PMID:19473032

  6. Abortiporus biennis tolerance to insoluble metal oxides: oxalate secretion, oxalate oxidase activity, and mycelial morphology.

    TOXLINE Toxicology Bibliographic Information

    Graz M; Jarosz-Wilko?azka A; Pawlikowska-Pawlega B

    2009-06-01

    The ability of Abortiporus biennis to tolerate and solubilize toxic metal oxides (Cu(2)O, Al(2)O(3), ZnO, CuFe(2)O(4)Zn, CdO, and MnO(2)) incorporated into agar media was investigated and the growth rate, oxalic acid secretion, and mycelial morphology were monitored. Among the tested metal oxides, formation of clear zones underneath the mycelium growing on Cu(2)O- and ZnO-amended plates was observed. ZnO, CdO and Cu(2)O caused the highest rate of fungal growth inhibition. An increased level of oxalic acid concentration was detected as a response of A. biennis to the presence of Cu(2)O, MnO(2), ZnO and CuFe(2)O(4)Zn in growth medium. The oxalate oxidase (OXO) was found to be responsible for oxalic acid degradation in A. biennis cultivated in metal-amended media. An increased level of OXO was observed in media amended with Cu(2)O, ZnO and MnO(2). Confocal microscopy used in this study revealed changes in mycelial morphology which appeared as increased hyphal branching, increased septation and increased spore number.

  7. Reregistration eligibility document (RED): Oxalic acid

    SciTech Connect

    Not Available

    1992-12-01

    EPA is directed by the Federal Insecticide, Fungicide, and Rodenticide Act as amended in 1988 (FIFRA '88) to review all pesticide products containing active ingredients initially registered before November 1, 1984, and to reregister those products that have a substantially complete data base and do not pose unreasonable adverse effects to people or the environment. This pesticide reregistration program is to be completed by the late 1990's. The Reregistration Eligibility Document (or RED) for oxalic acid discusses the scientific data and other information supporting EPA's regulatory conclusion that products containing a pesticide do not pose unreasonable risks when used as directed by Agency-approved labeling, and are eligible for reregistration.

  8. In vitro inhibition of calcium oxalate crystallization and crystal adherence to renal tubular epithelial cells by Terminalia arjuna.

    PubMed

    Mittal, A; Tandon, S; Singla, S K; Tandon, C

    2016-04-01

    Urolithiasis is a multifactorial disease and remains a public health problem around the world. Of all types of renal stones, calcium oxalate (CaOx) is the most common composition formed in the urinary system of the patients with urolithiasis. The present study is aimed at evaluating the antiurolithiatic properties of the Tris-Cl extract (TE) of Terminalia arjuna (T. arjuna). The antilithiatic activity of TE of T. arjuna was investigated on nucleation, aggregation, and growth of the CaOx crystals, as well as its protective potency was tested on oxalate-induced cell injury of NRK-52E renal epithelial cells. Also, in vitro antioxidant activity of TE T. arjuna bark was also determined. The TE of T. arjuna exhibited a concentration-dependent inhibition of nucleation and growth of CaOx crystals. Inhibition of aggregation of CaOx crystals remains constant. When NRK-52E cells were injured by exposure to oxalate for 48 h, the TE prevented the cells from injury and CaOx crystal adherence resulting in increased cell viability in a dose-dependent manner. The TE also scavenged the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals with an IC50 at 51.72 µg/mL. The results indicated that T. arjuna is a potential candidate for phytotherapy against urolithiasis as it attains the ability to inhibit CaOx crystallization and scavenge DPPH free radicals in vitro along with a cytoprotective role. PMID:26424092

  9. Mathematical model to estimate risk of calcium-containing renal stones

    NASA Technical Reports Server (NTRS)

    Pietrzyk, R. A.; Feiveson, A. H.; Whitson, P. A.

    1999-01-01

    BACKGROUND/AIMS: Astronauts exposed to microgravity during the course of spaceflight undergo physiologic changes that alter the urinary environment so as to increase the risk of renal stone formation. This study was undertaken to identify a simple method with which to evaluate the potential risk of renal stone development during spaceflight. METHOD: We used a large database of urinary risk factors obtained from 323 astronauts before and after spaceflight to generate a mathematical model with which to predict the urinary supersaturation of calcium stone forming salts. RESULT: This model, which involves the fewest possible analytical variables (urinary calcium, citrate, oxalate, phosphorus, and total volume), reliably and accurately predicted the urinary supersaturation of the calcium stone forming salts when compared to results obtained from a group of 6 astronauts who collected urine during flight. CONCLUSIONS: The use of this model will simplify both routine medical monitoring during spaceflight as well as the evaluation of countermeasures designed to minimize renal stone development. This model also can be used for Earth-based applications in which access to analytical resources is limited.

  10. Potential Pharmacologic Treatments for Cystinuria and for Calcium Stones Associated with Hyperuricosuria

    SciTech Connect

    Goldfarb, David S.

    2012-03-14

    Two new potential pharmacologic therapies for recurrent stone disease are described. The role of hyperuricosuria in promoting calcium stones is controversial with only some but not all epidemiologic studies demonstrating associations between increasing urinary uric acid excretion and calcium stone disease. The relationship is supported by the ability of uric acid to 'salt out' (or reduce the solubility of) calcium oxalate in vitro. A randomized, controlled trial of allopurinol in patients with hyperuricosuria and normocalciuria was also effective in preventing recurrent stones. Febuxostat, a nonpurine inhibitor of xanthine oxidase (also known as xanthine dehydrogenase or xanthine oxidoreductase) may have advantages over allopurinol and is being tested in a similar protocol, with the eventual goal of determining whether urate-lowering therapy prevents recurrent calcium stones. Treatments for cystinuria have advanced little in the past 30 years. Atomic force microscopy has been used recently to demonstrate that effective inhibition of cystine crystal growth is accomplished at low concentrations of L-cystine methyl ester and L-cystine dimethyl ester, structural analogs of cystine that provide steric inhibition of crystal growth. In vitro, L-cystine dimethyl ester had a significant inhibitory effect on crystal growth. The drug's safety and effectiveness will be tested in an Slc3a1 knockout mouse that serves as an animal model of cystinuria.

  11. Assessing applicants to the NASA flight program for their renal stone-forming potential.

    PubMed

    Pak, C Y; Hill, K; Cintron, N M; Huntoon, C

    1989-02-01

    Spaceflight could provoke formation of kidney stones, in part by causing hypercalciuria and hyperphosphaturia. Applicants for spaceflight who have metabolic or environmental derangements to begin with might be particularly susceptible to stone formation in space. We, therefore, analyzed 24-h urine samples for stone-forming risk factors in 104 male applicants before their selection into the astronaut-mission specialist corps. The urinary environment was abnormally supersaturated with calcium oxalate in 25.0% of applicants, brushite in 36.5%, and monosodium urate in 66.3%, predisposing these applicants to crystallization of stone-forming calcium salts. This high level of supersaturation was caused by both "metabolic" and environmental disturbances. Thus, hypercalciuria was found in 11.5% of applicants, hyperoxaluria in 2.9%, hyperuricosuria in 18.3% and hypocitraturia in 5.8%. Environmental derangements were generally more prominent, as indicated by low urine volume of less than 2 L.d-1 in 84.6%, high urinary phosphate in 24.4%, and high urinary sodium in 10.6% of applicants. The results suggest that most of the abnormal stone risk factors disclosed among applicants for spaceflight programs were environmental in origin. PMID:2930428

  12. Ureteroscopic retrograde intrarenal surgery after previous open renal stone surgery: initial experience.

    PubMed

    Osman, Mahmoud M; Gamal, Wael M; Gadelmoula, Mohamed M; Safwat, Ahmed S; Elgammal, Mohamed A

    2012-08-01

    The management of renal calculi following previous open surgery represents a challenge for urologists. The aim of this study is to evaluate the outcomes and safety of ureteroscopic laser retrograde intrarenal surgery (RIRS) for renal calculi following prior open renal surgery. The charts of 53 patients who underwent RIRS for renal calculi following prior open surgery for urolithiasis were reviewed. Both flexible and semi-rigid ureteroscopes were utilized together with holmium: YAG laser for stone disintegration. Intravenous urography, computed tomography (CT) and ultrasound were used to evaluate the patient, perioperatively. Stone size ranged from 5 to 32 mm (mean 14.3 mm). The mean operative time was 86 min (20-130). The overall stone-free rate was 92.4%. The overall stone-free rates after one and two-procedures were 79.2% (42 cases) and 92.4% (49 cases), respectively. Four patients (7.5%) had larger residual fragments, 2 (3.8%) of them underwent SWL, and 2 (3.8%) cases were followed up conservatively. Major complications were reported in two patients (3.8%). Stone analysis revealed calcium oxalate in 39 patients, uric acid in 5, calcium phosphate in 4, struvite in 3, and cystine in 2 cases. Ureteroscopic retrograde intrarenal surgery for renal calculi following prior open renal surgery was a minimally invasive, safe procedure with a high success rate. It is a viable alternative for PNL in managing recurrent renal calculi efficiently. PMID:22057206

  13. Fad diets and their effect on urinary stone formation

    PubMed Central

    Nouvenne, Antonio; Ticinesi, Andrea; Morelli, Ilaria; Guida, Loredana; Meschi, Tiziana

    2014-01-01

    The influence of unhealthy dietary habits on urinary stone formation has been widely recognized in literature. Dietary advice is indeed the cornerstone prescription for prevention of nephrolithiasis as well. However, only a small amount of medical literature has addressed the influence of popular or fad diets, often self-prescribed for the management of obesity and overweight or for cultural beliefs, on the risk of kidney stones. Thereby in this paper we analyze the current knowledge on the effects of some popular diets on overall lithogenic risk. High-protein diets, like Dukan diet, raise some concerns, since animal proteins are able to increase urinary calcium and to decrease urinary citrate excretion, thus leading to a high overall lithogenic risk. Low-carbohydrate diets, like Atkins diet or zone diet, may have a protective role against kidney stone formation, but there are also evidences stating that this dietary approach may rise calciuria and decrease citraturia, since it is generally associated to a relatively high intake of animal proteins. Vegan diet can be harmful for urinary stone disease, especially for the risk of hyperuricemia and micronutrient deficiencies, even if only few studies have addressed this specific matter. On the other side, the benefits of a lacto-ovo-vegetarian diet on kidney stone prevention have been largely emphasized, provided that the intake of calcium and oxalate is balanced. Traditional Mediterranean diet should exert a protective effect on nephrolithiasis as well, even if specific studies have not been carried out yet. High phytate and antioxidant content of this diet have however demonstrated to be beneficial in preventing the formation of new or recurrent calculi. Anyway, at the current state of knowledge, the most effective dietary approach to prevent kidney stone disease is a mild animal protein restriction, a balanced intake of carbohydrates and fats and a high intake of fruit and vegetables. Other fundamental aspects, which are often neglected in fad diets, are a normal intake of milk and dairy products and salt restriction. All these nutritional aspects should be greatly taken into account when patients who are willing to undergo fad or commercial diets ask for dietary advice. PMID:26816783

  14. Fad diets and their effect on urinary stone formation.

    PubMed

    Nouvenne, Antonio; Ticinesi, Andrea; Morelli, Ilaria; Guida, Loredana; Borghi, Loris; Meschi, Tiziana

    2014-09-01

    The influence of unhealthy dietary habits on urinary stone formation has been widely recognized in literature. Dietary advice is indeed the cornerstone prescription for prevention of nephrolithiasis as well. However, only a small amount of medical literature has addressed the influence of popular or fad diets, often self-prescribed for the management of obesity and overweight or for cultural beliefs, on the risk of kidney stones. Thereby in this paper we analyze the current knowledge on the effects of some popular diets on overall lithogenic risk. High-protein diets, like Dukan diet, raise some concerns, since animal proteins are able to increase urinary calcium and to decrease urinary citrate excretion, thus leading to a high overall lithogenic risk. Low-carbohydrate diets, like Atkins diet or zone diet, may have a protective role against kidney stone formation, but there are also evidences stating that this dietary approach may rise calciuria and decrease citraturia, since it is generally associated to a relatively high intake of animal proteins. Vegan diet can be harmful for urinary stone disease, especially for the risk of hyperuricemia and micronutrient deficiencies, even if only few studies have addressed this specific matter. On the other side, the benefits of a lacto-ovo-vegetarian diet on kidney stone prevention have been largely emphasized, provided that the intake of calcium and oxalate is balanced. Traditional Mediterranean diet should exert a protective effect on nephrolithiasis as well, even if specific studies have not been carried out yet. High phytate and antioxidant content of this diet have however demonstrated to be beneficial in preventing the formation of new or recurrent calculi. Anyway, at the current state of knowledge, the most effective dietary approach to prevent kidney stone disease is a mild animal protein restriction, a balanced intake of carbohydrates and fats and a high intake of fruit and vegetables. Other fundamental aspects, which are often neglected in fad diets, are a normal intake of milk and dairy products and salt restriction. All these nutritional aspects should be greatly taken into account when patients who are willing to undergo fad or commercial diets ask for dietary advice. PMID:26816783

  15. Bath Stone - a Possible Global Heritage Stone from England

    NASA Astrophysics Data System (ADS)

    Marker, Brian

    2014-05-01

    The Middle Jurassic strata of England have several horizons of oolitic and bioclastic limestones that provide high quality dimension stone. One of the most important is found in and near the City of Bath. The Great Oolite Group (Upper Bathonian) contains the Combe Down and Bath Oolites, consisting of current bedded oolites and shelly oolites, that have been used extensively as freestones for construction nearby, for prestigious buildings through much of southern England and more widely. The stone has been used to some extent since Roman times when the city, then known as Aquae Sulis, was an important hot spa. The stone was used to a limited extent through medieval times but from the early 18th century onwards was exploited on a large scale through surface quarrying and underground mining. The City was extensively redeveloped in the 18th to early 19th century, mostly using Bath Stone, when the spas made it a fashionable resort. Buildings from that period include architectural "gems" such as the Royal Crescent and Pulteney Bridge, as well as the renovated Roman Baths. Many buildings were designed by some of the foremost British architects of the time. The consistent use of this stone gives the City an architectural integrity throughout. These features led to the designation of the City as a World Heritage Site. It is a requirement in current City planning policy documents that Bath Stone should be used for new building to preserve the appearance of the City. More widely the stone was used in major houses (e.g. Buckingham Palace and Apsley House in London; King's Pavilion in Brighton); civic buildings (e.g. Bristol Guildhall; Dartmouth Naval College in Devon); churches and cathedrals (e.g. Truro Cathedral in Cornwall); and engineered structures (e.g. the large Dundas Aqueduct on the Kennet and Avon Canal). More widely, Bath Stone has been used in Union Station in Washington DC; Toronto Bible College and the Town Hall at Cape Town, South Africa. Extraction declined in the late 20th century but several quarries and underground mines remain operational providing stone for the local market, repair and maintenance of historic buildings and for special international projects. Reserves permitted for extraction are substantial and resources are fairly extensive so the stone will be accessible in the long term. Taking such points into account, it is suggested that Bath Stone should be recognised as a Global Heritage Stone Resource.

  16. Probabilistic Modeling of the Renal Stone Formation Module

    NASA Technical Reports Server (NTRS)

    Best, Lauren M.; Myers, Jerry G.; Goodenow, Debra A.; McRae, Michael P.; Jackson, Travis C.

    2013-01-01

    The Integrated Medical Model (IMM) is a probabilistic tool, used in mission planning decision making and medical systems risk assessments. The IMM project maintains a database of over 80 medical conditions that could occur during a spaceflight, documenting an incidence rate and end case scenarios for each. In some cases, where observational data are insufficient to adequately define the inflight medical risk, the IMM utilizes external probabilistic modules to model and estimate the event likelihoods. One such medical event of interest is an unpassed renal stone. Due to a high salt diet and high concentrations of calcium in the blood (due to bone depletion caused by unloading in the microgravity environment) astronauts are at a considerable elevated risk for developing renal calculi (nephrolithiasis) while in space. Lack of observed incidences of nephrolithiasis has led HRP to initiate the development of the Renal Stone Formation Module (RSFM) to create a probabilistic simulator capable of estimating the likelihood of symptomatic renal stone presentation in astronauts on exploration missions. The model consists of two major parts. The first is the probabilistic component, which utilizes probability distributions to assess the range of urine electrolyte parameters and a multivariate regression to transform estimated crystal density and size distributions to the likelihood of the presentation of nephrolithiasis symptoms. The second is a deterministic physical and chemical model of renal stone growth in the kidney developed by Kassemi et al. The probabilistic component of the renal stone model couples the input probability distributions describing the urine chemistry, astronaut physiology, and system parameters with the physical and chemical outputs and inputs to the deterministic stone growth model. These two parts of the model are necessary to capture the uncertainty in the likelihood estimate. The model will be driven by Monte Carlo simulations, continuously randomly sampling the probability distributions of the electrolyte concentrations and system parameters that are inputs into the deterministic model. The total urine chemistry concentrations are used to determine the urine chemistry activity using the Joint Expert Speciation System (JESS), a biochemistry model. Information used from JESS is then fed into the deterministic growth model. Outputs from JESS and the deterministic model are passed back to the probabilistic model where a multivariate regression is used to assess the likelihood of a stone forming and the likelihood of a stone requiring clinical intervention. The parameters used to determine to quantify these risks include: relative supersaturation (RS) of calcium oxalate, citrate/calcium ratio, crystal number density, total urine volume, pH, magnesium excretion, maximum stone width, and ureteral location. Methods and Validation: The RSFM is designed to perform a Monte Carlo simulation to generate probability distributions of clinically significant renal stones, as well as provide an associated uncertainty in the estimate. Initially, early versions will be used to test integration of the components and assess component validation and verification (V&V), with later versions used to address questions regarding design reference mission scenarios. Once integrated with the deterministic component, the credibility assessment of the integrated model will follow NASA STD 7009 requirements.

  17. Immunohistochemical localization and mRNA quantification of osteopontin and Tamm-Horsfall protein in canine renal tissue after potassium oxalate injection

    PubMed Central

    2014-01-01

    Background Urinary macromolecules contribute to promoting or inhibiting crystal retention in renal tissue and stone formation. Osteopontin (OPN) and Tamm-Horsfall protein (THP) are the most important proteins involved in this process. Although these two proteins were discovered a long time ago, their role in setting kidney stone formation has not yet been fully investigated. We conducted a study to explore the role of OPN and THP in canine renal oxalosis. Ten dogs were carefully examined prior to the study. Six dogs were assigned to the treatment group and were injected intravenously with 0.5M potassium oxalate (KOx). The other four dogs were assigned to a control group and were injected intravenously with 0.9% NaCl three times a day (tid) for 7 consecutive days. Then kidneys were harvested for pathological, immunohistochemical examination and OPN and THP mRNA expression levels were quantified by quantitative real-time PCR. Results Calcium oxalate crystals deposition was observed in both renal cortex and medulla. Immunohistochemistry examination revealed increased tissue expression of OPN in the renal tissue while THP was significantly decreased. OPN mRNA expression level significantly increased in treated dogs compared to that in the controls, while THP mRNA level significantly decreased. Conclusion Together, these results suggest that THP and OPN are both involved in the pathogenesis and response to oxalate exposure. PMID:24628885

  18. Oxalic acid production and aluminum tolerance in Pseudomonas fluorescens.

    PubMed

    Hamel, R; Levasseur, R; Appanna, V D

    1999-08-30

    13C NMR studies on intact cells from Al-stressed Pseudomonas fluorescens incubated with citric acid or Al-citrate yielded peaks at 158 and 166 ppm that were attributable to free and complexed oxalic acid, respectively. The presence of oxalic acid was further confirmed with the aid of oxalate oxidase. These peaks were not discernable in experiments performed with cells taken from control cultures. Enzymatic analyses of cell fractions showed the highest production of oxalic acid in the inner membrane fraction of Al-stressed cells incubated with glyoxylate. There was an eight-fold increase in the synthesis of oxalic acid in the inner membrane fraction from the Al-stressed cells compared to the control cells. Although oxalic acid production was observed when citrate, Al-citrate and isocitrate were utilized as substrates, the inner membrane fraction did not mediate the formation of oxalic acid from glycine/pyruvate, glycolic acid, oxaloacetate or ascorbate. These data suggest that the increased oxalic acid production in response to Al stress is effected via the oxidation of glyoxylate. PMID:10612061

  19. Characterization of Medicago truncatula reduced calcium oxalate crystal mutant alleles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calcium oxalate crystal formation is common in plants. Formation of these crystals has been shown to function in plant defense, calcium regulation, and aluminum tolerance. Although calcium oxalate is common and plays important roles in plant development, our understanding of how these crystals form ...

  20. Oxalate Synthesis and Pyrolysis: A Colorful Introduction to Stoichiometry

    ERIC Educational Resources Information Center

    Vannatta, Michael W.; Richards-Babb, Michelle; Sweeney, Robert J.

    2010-01-01

    Metal oxalate synthesis and pyrolysis provides an opportunity for students to (i) learn stoichiometry, (ii) experience the consequences of proper stoichiometric calculations and experimental techniques, and (iii) be introduced to the relevance of chemistry by highlighting oxalates in context, for example, usages and health effects. At our…

  1. Oxalate Synthesis and Pyrolysis: A Colorful Introduction to Stoichiometry

    ERIC Educational Resources Information Center

    Vannatta, Michael W.; Richards-Babb, Michelle; Sweeney, Robert J.

    2010-01-01

    Metal oxalate synthesis and pyrolysis provides an opportunity for students to (i) learn stoichiometry, (ii) experience the consequences of proper stoichiometric calculations and experimental techniques, and (iii) be introduced to the relevance of chemistry by highlighting oxalates in context, for example, usages and health effects. At our

  2. Calcium Oxalate Accumulation in Malpighian Tubules of Silkworm (Bombyx mori)

    NASA Astrophysics Data System (ADS)

    Wyman, Aaron J.; Webb, Mary Alice

    2007-04-01

    Silkworm provides an ideal model system for study of calcium oxalate crystallization in kidney-like organs, called Malpighian tubules. During their growth and development, silkworm larvae accumulate massive amounts of calcium oxalate crystals in their Malpighian tubules with no apparent harm to the organism. This manuscript reports studies of crystal structure in the tubules along with analyses identifying molecular constituents of tubule exudate.

  3. 21 CFR 520.1263a - Lincomycin hydrochloride monohydrate tablets and sirup.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Lincomycin hydrochloride monohydrate tablets and sirup. 520.1263a Section 520.1263a Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1263a Lincomycin hydrochloride monohydrate tablets and sirup. (a) Specifications. The...

  4. 21 CFR 520.1263a - Lincomycin hydrochloride monohydrate tablets and sirup.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Lincomycin hydrochloride monohydrate tablets and sirup. 520.1263a Section 520.1263a Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1263a Lincomycin hydrochloride monohydrate tablets and sirup. (a) Specifications. The...

  5. 21 CFR 520.1263a - Lincomycin hydrochloride monohydrate tablets and sirup.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Lincomycin hydrochloride monohydrate tablets and sirup. 520.1263a Section 520.1263a Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1263a Lincomycin hydrochloride monohydrate tablets and sirup. (a) Specifications. The...

  6. 21 CFR 520.1263 - Lincomycin hydrochloride monohydrate oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Lincomycin hydrochloride monohydrate oral dosage forms. 520.1263 Section 520.1263 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1263 Lincomycin hydrochloride monohydrate oral dosage forms....

  7. 21 CFR 520.1263 - Lincomycin hydrochloride monohydrate oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Lincomycin hydrochloride monohydrate oral dosage forms. 520.1263 Section 520.1263 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1263 Lincomycin hydrochloride monohydrate oral dosage forms....

  8. 21 CFR 520.1263a - Lincomycin hydrochloride monohydrate tablets and sirup.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Lincomycin hydrochloride monohydrate tablets and sirup. 520.1263a Section 520.1263a Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1263a Lincomycin hydrochloride monohydrate tablets and sirup. (a) Specifications. The...

  9. 21 CFR 520.1263 - Lincomycin hydrochloride monohydrate oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Lincomycin hydrochloride monohydrate oral dosage forms. 520.1263 Section 520.1263 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1263 Lincomycin hydrochloride monohydrate oral dosage forms....

  10. Reduction of Oxalate Levels in Tomato Fruit and Consequent Metabolic Remodeling Following Overexpression of a Fungal Oxalate Decarboxylase1[W

    PubMed Central

    Chakraborty, Niranjan; Ghosh, Rajgourab; Ghosh, Sudip; Narula, Kanika; Tayal, Rajul; Datta, Asis; Chakraborty, Subhra

    2013-01-01

    The plant metabolite oxalic acid is increasingly recognized as a food toxin with negative effects on human nutrition. Decarboxylative degradation of oxalic acid is catalyzed, in a substrate-specific reaction, by oxalate decarboxylase (OXDC), forming formic acid and carbon dioxide. Attempts to date to reduce oxalic acid levels and to understand the biological significance of OXDC in crop plants have met with little success. To investigate the role of OXDC and the metabolic consequences of oxalate down-regulation in a heterotrophic, oxalic acid-accumulating fruit, we generated transgenic tomato (Solanum lycopersicum) plants expressing an OXDC (FvOXDC) from the fungus Flammulina velutipes specifically in the fruit. These E8.2-OXDC fruit showed up to a 90% reduction in oxalate content, which correlated with concomitant increases in calcium, iron, and citrate. Expression of OXDC affected neither carbon dioxide assimilation rates nor resulted in any detectable morphological differences in the transgenic plants. Comparative proteomic analysis suggested that metabolic remodeling was associated with the decrease in oxalate content in transgenic fruit. Examination of the E8.2-OXDC fruit proteome revealed that OXDC-responsive proteins involved in metabolism and stress responses represented the most substantially up- and down-regulated categories, respectively, in the transgenic fruit, compared with those of wild-type plants. Collectively, our study provides insights into OXDC-regulated metabolic networks and may provide a widely applicable strategy for enhancing crop nutritional value. PMID:23482874

  11. Reduction of oxalate levels in tomato fruit and consequent metabolic remodeling following overexpression of a fungal oxalate decarboxylase.

    PubMed

    Chakraborty, Niranjan; Ghosh, Rajgourab; Ghosh, Sudip; Narula, Kanika; Tayal, Rajul; Datta, Asis; Chakraborty, Subhra

    2013-05-01

    The plant metabolite oxalic acid is increasingly recognized as a food toxin with negative effects on human nutrition. Decarboxylative degradation of oxalic acid is catalyzed, in a substrate-specific reaction, by oxalate decarboxylase (OXDC), forming formic acid and carbon dioxide. Attempts to date to reduce oxalic acid levels and to understand the biological significance of OXDC in crop plants have met with little success. To investigate the role of OXDC and the metabolic consequences of oxalate down-regulation in a heterotrophic, oxalic acid-accumulating fruit, we generated transgenic tomato (Solanum lycopersicum) plants expressing an OXDC (FvOXDC) from the fungus Flammulina velutipes specifically in the fruit. These E8.2-OXDC fruit showed up to a 90% reduction in oxalate content, which correlated with concomitant increases in calcium, iron, and citrate. Expression of OXDC affected neither carbon dioxide assimilation rates nor resulted in any detectable morphological differences in the transgenic plants. Comparative proteomic analysis suggested that metabolic remodeling was associated with the decrease in oxalate content in transgenic fruit. Examination of the E8.2-OXDC fruit proteome revealed that OXDC-responsive proteins involved in metabolism and stress responses represented the most substantially up- and down-regulated categories, respectively, in the transgenic fruit, compared with those of wild-type plants. Collectively, our study provides insights into OXDC-regulated metabolic networks and may provide a widely applicable strategy for enhancing crop nutritional value. PMID:23482874

  12. Nutritional Management of Kidney Stones (Nephrolithiasis)

    PubMed Central

    Segal, Adam M.; Seifter, Julian L.; Dwyer, Johanna T.

    2015-01-01

    The incidence of kidney stones is common in the United States and treatments for them are very costly. This review article provides information about epidemiology, mechanism, diagnosis, and pathophysiology of kidney stone formation, and methods for the evaluation of stone risks for new and follow-up patients. Adequate evaluation and management can prevent recurrence of stones. Kidney stone prevention should be individualized in both its medical and dietary management, keeping in mind the specific risks involved for each type of stones. Recognition of these risk factors and development of long-term management strategies for dealing with them are the most effective ways to prevent recurrence of kidney stones. PMID:26251832

  13. Stone weathering in Southeast England

    NASA Astrophysics Data System (ADS)

    Jaynes, Suzanne M.; Cooke, R. U.

    A 2-year exposure programme of Portland stone and Monk's Park stone at 25 sites in SE England revealed significant differences in weight losses, changes in surface roughness and chemistry at each location that can be attributed to the activity of air pollutants and salts. In particular it was shown that weight loss of exposed samples can be attributed to both solution and sulphation (the latter probably contributing an average of at least 39% for Portland stone, 44% of Monk's Park stone); that salt attack of sheltered samples is evident at Bletchley (brickmaking) and coastal locations; and surface roughness changes, measured by Ra values on a Surfcom plotter, appear to be particularly sensitive to processes of surface disruption, such as salt weathering. Analysis of SO 2 data at the sites showed significantly higher concentrations at London sites. The corresponding gradient in weight loss was gentler, probably as the result of the influence of other atmospheric variables.

  14. Improved ureteral stone fragmentation catheter

    NASA Technical Reports Server (NTRS)

    Gammell, P. M.

    1981-01-01

    Catheter includes fiber optic viewer, more reliable ultrasonic probe, and better contact sensor. It is guided by four steering wires, and irrigation fluid is supplied through lumen to remove stone fragments.

  15. The true stone composition and abnormality of urinary metabolic lithogenic factors of rats fed diets containing melamine.

    PubMed

    Cong, Xiaoming; Gu, Xiaojian; Xu, Yan; Sun, Xizhao; Shen, Luming

    2014-06-01

    To better understand the toxicity of melamine to humans, the stone composition and urinary metabolic lithogenic factors of rats fed diets containing melamine including the infant's melamine-induced stone composition were studied. Sixty 4-week-old male rats divided into three groups were, respectively, fed diets containing no melamine (control), 0.1% melamine, and 1% melamine for 4 weeks. At the end of experiment, the collected stones and 24-h urines from rats were, respectively, measured with compositions and metabolic lithogenic parameters. The stone from an infant who ingested melamine-adulterated formula was also included in compositional analysis. Across three groups, the stone was only detected in 1% melamine group, with composition of almost melamine different from the affected infant's stone composed of melamine and uric acid with a ratio of 1:2. Compared with control group, urine calcium and phosphate excretions were significantly increased in 1% melamine group. Urine uric acid excretion was significantly increased but citrate excretion was significantly decreased in 0.1% and 1% melamine groups. Urine oxalate excretion and pH were indicated without any significant difference. In addition based on urine physicochemical characters, melamine-uric acid stone seems difficult to be formed in the rats due to their characters of urine high-pH and low-uric acid. These results demonstrated that (1) the stone composition of rats fed melamine was not and could not be as that of infants fed melamine-adulterated formula, two species had a different mechanism of melamine-induced stone formation; (2) the exposure of melamine could result in abnormalities of urine metabolic lithogenic factors to rats, perhaps as well as human beings. PMID:24287677

  16. The preservation of urine samples for determination of renal stone risk factors

    NASA Technical Reports Server (NTRS)

    Nicar, M. J.; Hsu, M. C.; Johnson, T.; Pak, C. Y.

    1987-01-01

    A preservation technique for urine specimens before determination of stone risk factors was evaluated. The purpose of these experiments was to prove the effectiveness of the preservatives used to prevent changes in the concentrations of those constituents measured. Measured concentrations in fresh specimens were compared with those in the same specimens after storage with the preservatives. Refrigeration at 4 degrees C up to five days was appropriate in a laboratory setting, as no significant changes in urinary concentrations occurred. Refrigeration, however, did not offer a convenient method for shipping. Chemical preservation was found to be an effective alternative to refrigeration. Thymol prevented changes in concentration of pH, citrate, uric acid, sulfate, sodium, potassium, and cyclic AMP, while a mixture of hydrochloric (HCl) acid and boric acid prevented changes in calcium, magnesium, phosphorus, oxalate, ammonium, and creatinine. Thus, the addition of thymol or HCl/boric acid to urine specimens will prevent significant changes in the concentrations of stone risk factors.

  17. Lunar stone saw

    NASA Technical Reports Server (NTRS)

    Clark, Tom; Croker, Todd; Hines, Ken; Knight, Mike; Walton, Todd

    1988-01-01

    This project addresses the problem of cutting lunar stones into blocks to be used to construct shelters to protect personnel and equipment from harmful solar radiation. This plant will manufacture 6 in x 1 ft x 2 ft blocks and will be located near the south pole to allow it to be in the shade at all times. This design uses a computer controlled robot, a boulder handler that uses hydraulics for movement, a computer system that used 3-D vision to determine the size of boulders, a polycrystalline diamond tipped saw blade that utilizes radiation for cooling, and a solar tower to collect solar energy. Only two electric motors are used in this plant because of the heavy weight of electric motors and the problem of cooling them. These two motors will be cooled by thermoelectric cooling. All other motors and actuators are to be hydraulic. The architectural design for the building as well as the conceptual design of the machines for cutting the blocks are described.

  18. Purbeck Stone - A possible Global Heritage Stone from England

    NASA Astrophysics Data System (ADS)

    Marker, Brian

    2014-05-01

    By definition, a Global Heritage Stone Resource (GHSR) should have international significance. The Purbeck Group of uppermost Jurassic to lowermost Cretaceous age (Tithonian- Berriasian) outcrops mainly in the Purbeck area of Dorset, England. It was deposited in shallow freshwater to brackish lagoons with occasional marine incursions. Limestones, mainly biosparites, occur at 6 main levels. Differences in bed thickness, jointing and hardness make it suitable for a variety of purposes including dimension stone, monumental and ornamental stone, roofing tiles, paving, flooring and rockery stone. Near the top of the sequence is a dark gastropod biosparite, traditionally called Purbeck Marble, easily carved, which has been extensively used for decorative interior work in churches and cathedrals particularly for fonts, tombs, flooring and facings on columns for example in the medieval cathedrals of Salisbury, Exeter, Durham, York and Wells and Worcester and Westminster Abbey. The stone was extracted at least from Roman times (1st century AD) through the medieval period. Quarrying expanded from about 1700 reaching a peak in the late 18th and 19th centuries. Stone was transported first by sea but later by rail for wider use. Used in many local buildings, it gives an important element of local character. Many of the villages are designated conservation areas with a requirement for repair, maintenance and new building using local stone. Initially the stone was taken from quarries but was later mined. The number of operating companies declined from 15 to 5 over the past 40 years, with 10 active small quarries. Outputs are from few hundred tonnes to a few thousand tonnes per annum or about 9 to 12 years of permitted reserves but the Planning Authority intends to make sufficient provision for production at recent levels for their development plan period. The extraction sites are in an Area of Outstanding Natural Beauty and close to Jurassic Coast World Heritage Site. This might be a test case for considering whether a stone with this history is significant enough to be designated as a GHSR or is, rather, of national significance.

  19. Heterogeneous nucleation of calcium oxalate on native oxide surfaces

    SciTech Connect

    Song, L.; Pattillo, M.J.; Graff, G.L.; Campbell, A.A.; Bunker, B.C.

    1994-04-01

    The aqueous deposition of calcium oxalate onto colloidal oxides has been studied as a model system for understanding heterogeneous nucleation processes of importance in biomimetic synthesis of ceramic thin films. Calcium oxalate nucleation has been monitored by measuring induction times for nucleation using Constant Composition techniques and by measuring nucleation densities on extended oxide surfaces using an atomic force microscope. Results show that the dependence of calcium oxalate nucleation on solution supersaturation fits the functional form predicted by classical nucleation theories. Anionic surfaces appear to promote nucleation better than cationic surfaces, lowering the effective energy barrier to heterogeneous nucleation.

  20. Dual-energy dual-source CT with additional spectral filtration can improve the differentiation of non-uric acid renal stones: An ex vivo phantom study

    PubMed Central

    Qu, Mingliang; Ramirez Giraldo, Juan C.; Leng, Shuai; Williams, James C.; Vrtiska, Terri J.; Lieske, John C.; McCollough, Cynthia H.

    2014-01-01

    Purpose To determine the ex vivo ability of dual-energy, dual-source computed tomography (DE-DSCT) with additional tin filtration to differentiate between five groups of human renal stone types. Methods Forty-three renal stones of ten types were categorized into five primary groups based on effective atomic numbers, which were calculated as the weighted average of the atomic numbers of constituent atoms. Stones were embedded in porcine kidneys and placed in a 35cm water phantom. DE-DSCT scans were performed with and without tin filtration at 80/140kV. The CT number ratio [CTR=CT(low)/CT(high)] was calculated on a volumetric voxel-by-voxel basis for each stone. Statistical analysis was performed and receiver operating characteristic (ROC) curves were plotted to compare the difference in CTR with and without tin filtration, and to measure the discrimination between stone groups. Results CTR of non-uric acid stones increased on average by 0.17 (range 0.030.36) with tin filtration. The CTR values for non-uric acid stone groups were not significantly different (p>0.05) between any of the two adjacent groups without tin filtration. Use of the additional tin filtration on the high-energy x-ray tube significantly improved the separation of non-uric acid stone types by CTR (p<0.05). The area under the ROC curve increased from 0.780.84 without fin filtration to 0.890.95 with tin filtration. Conclusion Our results demonstrated better separation between different stone types when additional tin filtration was used on DE-DSCT. The increased spectral separation allowed a 5-group stone classification scheme. Some overlapping between particular stone types still exists, including brushite and calcium oxalate. PMID:21606290

  1. Oxalate balance in fat sand rats feeding on high and low calcium diets.

    PubMed

    Palgi, Niv; Ronen, Zeev; Pinshow, Berry

    2008-07-01

    Oxalate reduces calcium availability of food because it chelates calcium, forming the sparingly soluble salt calcium-oxalate. Nevertheless, fat sand rats (Psammomys obesus; Gerbillinae) feed exclusively on plants containing much oxalate. We measured the effects of calcium intake on oxalate balance by comparing oxalate intake and excretion in wild fat sand rats feeding on their natural, oxalate-rich, calcium-poor diet with commercially-bred fat sand rats feeding on an artificial, calcium-rich, oxalate-poor diet of rodent pellets. We also tested for the presence of the oxalate degrading bacterium Oxalobacter sp. in the faeces of both groups. Fat sand rats feeding on saltbush ingested significantly more oxalate than fat sand rats feeding on pellets (P < 0.001) and excreted significantly more oxalate in urine and faeces (P < 0.01 for both). However the fraction of oxalate recovered in excreta [(oxalate excreted in urine + oxalate excreted in faeces)/oxalate ingested] was significantly higher in pellet-fed fat sand rats (61%) than saltbush-fed fat sand rats (27%). We found O. sp. in the faeces of both groups indicating that fat sand rats harbor oxalate degrading bacteria, and these are able, to some extent, to degrade oxalate in its insoluble form. PMID:18210126

  2. Urinary stones in Eastern Saudi Arabia

    PubMed Central

    Alkhunaizi, Ahmed Mansour

    2016-01-01

    Introduction: Nephrolithiasis is a common problem worldwide especially in areas of the hot climate like Saudi Arabia. The aim of this analysis was to study the characteristics of urinary stones in Eastern Saudi Arabia and to report the following: Composition of urinary stones, age and gender distribution, seasonal variation of stone development, comorbid conditions associated with stone development and the incidence of urinary stones. Methods: All urinary stones that were submitted to the Johns Hopkins Aramco Healthcare, previously Saudi Aramco Medical Services Organization for analysis from January 2011 through January 2013 were analyzed. Results: A total of 384 urinary stones were collected and submitted for analysis from 347 patients. There was a male predominance with a male: female ratio of 3.9:1. The average age was 48.5 ± 12.8 years. Weight abnormality was predominant in both genders, and especially females. Calcium-based stones constituted the great majority (84.6%) followed by uric acid stones (12.8%). The other forms of stones were rare. More stones were recovered during the hot season, May to September. The calculated annual incidence of urolithiasis was 111/100,000 individuals. Conclusion: Calcium based stones are the most common urinary stones observed in Eastern Saudi Arabia. There is a clear association between the diagnosis of urinary stones and the hot season PMID:26834393

  3. The risk of renal stone formation during and after long duration space flight

    NASA Technical Reports Server (NTRS)

    Whitson, P. A.; Pietrzyk, R. A.; Morukov, B. V.; Sams, C. F.

    2001-01-01

    BACKGROUND: The formation of a renal stone during space flight may have serious negative effects on the health of the crewmember and the success of the mission. Urinary biochemical factors and the influence of dietary factors associated with renal stone development were assessed during long duration Mir Space Station missions. METHODS: Twenty-four-hour urine samples were collected prior to, during and following long duration space flight. The relative urinary supersaturation of calcium oxalate, calcium phosphate (brushite), sodium urate, struvite and uric acid were determined. RESULTS: Changes in the urinary biochemistry of crewmembers during long duration spaceflight demonstrated increases in the supersaturation of the stone-forming salts. In-flight hypercalciuria was evident in a number of individual crewmembers and 24-hour dietary fluid intake and urine volume were significantly lower. During flight, there was a significant increase in brushite supersaturation. CONCLUSIONS: These data suggest acute effects of space flight and postflight changes in the urinary biochemistry favoring increased crystallization in the urine. The effects of dietary intake, especially fluid intake, may have a significant impact on the potential for renal stone formation. Efforts are now underway to assess the efficacy of a countermeasure to mitigate the increased risk. Copyright 2001 S. Karger AG, Basel.

  4. Identification of calcium oxalate crystals using alizarin red S stain.

    PubMed

    Proia, A D; Brinn, N T

    1985-02-01

    Calcium oxalate crystals stain with alizarin red S at a pH of 7.0 but not at a pH of 4.2. In contrast, calcium phosphate and calcium carbonate stain at a pH of both 7.0 and 4.2. This difference allows presumptive identification of calcium oxalate deposits. The identity of calcium oxalate can then be confirmed by its insolubility in 2M acetic acid, since both calcium carbonate and calcium phosphate are soluble. We have applied this procedure for several years and have found it to be a rapid, reliable, and technically simple procedure for distinguishing calcium oxalate from other calcium deposits. PMID:2579619

  5. p38 MAPK mediates calcium oxalate crystal-induced tight junction disruption in distal renal tubular epithelial cells

    PubMed Central

    Peerapen, Paleerath; Thongboonkerd, Visith

    2013-01-01

    We examined whether p38 MAPK plays role in calcium oxalate monohydrate (COM) crystal-induced tight junction disruption. Polarized MDCK cells were pretreated with or without 20??M SB239063 (p38 MAPK inhibitor) for 2-h, and then incubated with 100??g/ml COM crystals for up to 48-h. Western blotting showed increased level of phospho-p38, not total p38, in COM-treated cells, whereas SB239063 pretreatment successfully maintained phospho-p38 at its basal level. COM crystals also caused decreased levels of two tight junction proteins, zonula occludens-1 (ZO-1) and occludin. Immunofluorescence study revealed disruption of tight junction, redistribution, and dissociation of ZO-1 and occludin. Moreover, transepithelial resistance (TER) showed defective barrier function, whereas Western blotting for Na+/K+-ATPase-?1 revealed defective fence function of tight junction in COM-treated cells. All these expression and functional defects were successfully prevented by SB239063 pretreatment. These findings indicate that COM crystals cause tight junction disruption in distal renal tubular epithelial cells through p38 MAPK activation. PMID:23304432

  6. Effect of sodium copper chlorophyllin on the formation of calcium oxalate crystals in rat kidney.

    PubMed

    Tawashi, R; Cousineau, M; Sharkawi, M

    1980-09-01

    We induced the deposition of calcium oxalate crystals in rat kidney by intraperitoneal administration of 4-hydroxy-L-proline or sodium oxalate and studied the amounts and size distribution characteristics of the deposited crystals. Intravenous administration of sodium copper chlorophyllin inhibited the deposition and growth of calcium oxalate crystals induced by 4-hydroxy-L-proline or sodium oxalate. This finding may be of importance in calcium oxalate urolithiasis. PMID:7053081

  7. Thermodynamics of hydrothermal systems with oxalate ion

    NASA Astrophysics Data System (ADS)

    Khodakovsky, I. L.; Devina, O. A.

    2009-04-01

    The geochemical and industrial significance of oxalates have led to great interest in the behavior of oxalate ion in hydrothermal systems. On the basis of a study by G.B. Naumov et al (1971) of gaseous-liquid inclusions it is shown that whewellite (CaC2O4H2O) which was found in quartz-calcite-fluorite veins in the uranium ore deposit of the Eastern Transbaikal region was formed at temperatures about 150C and pressure CO2 of 600-860 atm. The isotopic composition of carbon for these hydrothermal whewellite samples was determined by Galimov et al (1975): Delta13C from -1.56 to -2.22%. In a continuation of the study of organic-acid-water-rock interactions the thermodynamics of hydrothermal equilibriums for the systems Ox-H, Ox-H-Ca, Ox-H-Mg (where Ox = C2O42-), are described up to 200C. The key network reactions and compounds related to the aqueous ion C2O42- are discussed and used to define the key values. The critical evaluation of thermodynamic properties for this ion is a part of the development of the new key values system for the joint thermodynamic database in the Internet. The evaluation involves the analysis of the enthalpy changes, Gibbs energy changes, and the entropy calculations for all key substances in the key network. A consistent set of thermodynamic property values is given for ?-H2C2O4(cr), ?-H2C2O4(cr), H2C2O4H2O(cr), CaC2O4(cr), CaC2O4H2O(cr,whewellite), NaC2O4(cr,natroxalate), MgC2O42H2O(cr,glushinskite) and aqueous species C2O42-, HC2O4-, H2C2O4, CaC2O4. This study was funded by Russian Foundation for Basic Research (project N 07-05-01108).

  8. Multiorgan crystal deposition following intravenous oxalate infusion in rat

    SciTech Connect

    Blumenfrucht, M.J.; Cheeks, C.; Wedeen, R.P.

    1986-06-01

    Deposition of calcium oxalate is responsible for the pathologic manifestations of oxalosis and may contribute to multiorgan dysfunction in uremia and to the progression of renal damage after renal failure is established. We have developed a rat model of oxalosis using a single intravenous injection of sodium oxalate, 0.3 mmol./kg. body weight, in rats. Polarized light microscopy and section freeze-dry autoradiography were used to identify /sup 14/C-oxalate within the renal parenchyma and in extrarenal organs. /sup 14/C-oxalate crystals under three mu in length were identified within one min. of injection in proximal tubule lumens. Section freeze-dry autoradiography showed occasional minute crystals within glomeruli, heart, lung and liver at one hr. In contrast to concentrative cellular uptake demonstrated in rat renal cortical slices in vitro, intracellular accumulation of /sup 14/C-oxalate could not be detected in vivo. Within the first 24 hr., renal oxalate retention reached a maximum of 25 +/- 4 per cent of the injected dose/gm. kidney compared to a maximum of only 7 +/- 3 per cent/gm. kidney after intraperitoneal administration. Although less than one per cent dose/gm. kidney remained after one week, crystal fragments were scattered throughout the cortex and medulla, often surrounded by foci of interstitial nephritis. The retention of crystals in kidney and other body organs following i.v. oxalate provides a model of oxalosis which stimulates pathophysiologic events in a variety of clinical situations characterized by transiently or persistently elevated serum oxalate.

  9. Biogenic and anthropogenic sources of oxalate in PM2.5 in a mega city, Shanghai

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Gu, Zeping; Feng, Jialiang; Liu, Xiaohuan; Yao, Xiaohong

    2014-03-01

    In this study, thirty-seven 4-6 h PM2.5 samples were collected in both cold and warm seasons in 2006-2008 at an urban site in Shanghai (3116?47?N, 12127?15?E) for an investigation of the origins of oxalate. In the cold season, the oxalate from biomass burning accounted for 30 11% (average standard deviation) of the observed oxalate using K+ as a tracer, while the oxalate oxidized from biogenic volatile organic species (BVOC) might be negligible because emissions of BVOC were only about 1/50 of volatile anthropogenic aromatics as reported in literature. The secondary oxalate (oxalate not from biomass burning) moderately correlated with sulfate and was more likely oxidized from anthropogenic aromatics. In the warm season, the oxalate from biomass burning accounted for 11 8% of the observed oxalate. The low percentage was partially associated with the southeast wind while the open biomass burning occurred mainly in the northwest to the sampling site. In the warm-season samples containing low concentrations of sulfate, the secondary oxalate was also moderately correlated with sulfate. Further analysis showed that cloud (or fog) processed oxalate from biogenic precursors probably dominated the secondary oxalate in these samples. Higher concentrations of oxalate and higher ratio of oxalate to sulfate in the remaining warm-season samples than in cold-season samples also suggested that the oxalate derived from biogenic precursors was also likely an important contributor to the secondary oxalate.

  10. Acute oxalate nephropathy after ingestion of star fruit.

    PubMed

    Chen, C L; Fang, H C; Chou, K J; Wang, J S; Chung, H M

    2001-02-01

    Acute oxalate nephropathy associated with ingestion of star fruit (carambola) has not been reported before. We report the first two cases. These patients developed nausea, vomiting, abdominal pain, and backache within hours of ingesting large quantities of sour carambola juice; then acute renal failure followed. Both patients needed hemodialysis for oliguric acute renal failure, and pathologic examinations showed typical changes of acute oxalate nephropathy. The renal function recovered 4 weeks later without specific treatment. Sour carambola juice is a popular beverage in Taiwan. The popularity of star fruit juice is not compatible with the rare discovery of star fruit-associated acute oxalate nephropathy. Commercial carambola juice usually is prepared by pickling and dilution processes that reduce oxalate content markedly, whereas pure fresh juice or mild diluted postpickled juice for traditional remedies, as used in our cases, contain high quantities of oxalate. An empty stomach and dehydrated state may pose an additional risk for development of renal injury. To avoid acute oxalate nephropathy, pure sour carambola juice or mild diluted postpickled juice should not be consumed in large amounts, especially on an empty stomach or in a dehydrated state. PMID:11157385

  11. Oxalate nephropathy in free-living American bullfrog tadpoles.

    PubMed

    Tokiwa, Toshihiro; Kadekaru, Sho; Ito, Masao; Yoshida, Makoto; Une, Yumi

    2015-10-27

    In February 2014, wild American bullfrog Lithobates catesbeianus tadpoles from an artificial pond in the Kyusyu region, Japan, presented with coelomic and subcutaneous edema and erythema within the skin. A pathological examination of 57 tadpoles of American bullfrogs in the region was conducted to evaluate the disease. Crystal deposition of varying degrees was found in the kidneys of 35 tadpoles (61.4%). The crystals were transparent, pleomorphic in shape, highly birefringent in polarized light, and arranged in a radial pattern within the renal tubular lumen. Using Alizarin Red S stain and liquid chromatography, these crystals were identified as calcium oxalate. Severe coelomic and subcutaneous edema was observed in 7 of these 35 tadpoles (20.0%). Ammonia levels in coelomic fluid were extremely elevated (>1000 µg dl(-1)) in 4 tadpoles examined. These findings suggest that oxalate deposition in kidneys causes metabolic disorder with renal nephropathy. The source of the oxalate could not be determined; however, the presence of calcium oxalates in pond sediments, as revealed by liquid chromatography, suggested that the deposition was most likely due to ingestion of oxalate materials from the environment. This is the first report of oxalate nephropathy in free-living amphibians. PMID:26503774

  12. Hydrothermal synthesis of uranyl squarates and squarate-oxalates. Hydrolysis trends and in situ oxalate formation

    SciTech Connect

    Rowland, Clare E.; Cahill, Christopher L.

    2010-06-16

    We report the synthesis of two uranyl squarates and two mixed-ligand uranyl squarate-oxalates from aqueous solutions under hydrothermal conditions. These products exhibit a range of uranyl building units from squarates with monomers in (UO2)2(C4O4)56NH44H2O (1; a = 16.731(17) , b = 7.280(8) , c = 15.872(16) , ? = 113.294(16), monoclinic, P21/c) and chains in (UO2)2(OH)2(H2O)2(C4O4) (2; a = 12.909(5) , b = 8.400(3) , c = 10.322(4) , ? = 100.056(7), monoclinic, C2/c) to two squarate-oxalate polymorphs with dimers in (UO2)2(OH)(C4O4)(C2O4)NH4H2O (3; a = 9.0601(7) , b = 15.7299(12) , c = 10.5108(8) , ? = 106.394(1), monoclinic, P21/n; and 4; a = 8.4469(6) , b = 7.7589(5) , c = 10.5257(7) , ? = 105.696(1), monoclinic, P21/m). The dominance at low pH of monomeric species and the increasing occurrence of oligomeric species with increasing pH suggests that uranyl hydrolysis, mUO22+ + NH2O ? [(UO2)m(OH)n]2m-n + nH+, has a significant role in the identity of the inorganic building unit. Additional factors that influence product assembly include in situ hydrolysis of squaric acid to oxalic acid, dynamic metal to ligand concentration, and additional binding modes resulting from the introduction of oxalate anions. These points and the effects of uranyl hydrolysis with changing pH are discussed in the context of the compounds presented herein.

  13. Kidney Stones in Children and Teens

    MedlinePLUS

    ... Email Print Share Kidney Stones in Children and Teens Page Content Article Body ​Kidney stones are hard ... age, even in premature infants , most occur in teens , with teen girls having the highest incidence. Types ...

  14. "Stone Age" Fun: Releasing the Animal Within.

    ERIC Educational Resources Information Center

    Geist, Janet Marie

    2000-01-01

    Discusses a fifth-grade sculpture project that uses a subtractive, rather than additive, technique. Students carve an animal sculpture from a block of simulated stone compound. Explains the process and how to make the simulated stone compound. (CMK)

  15. Kidney stones - what to ask your doctor

    MedlinePLUS

    A kidney stone is a solid piece of material that forms in your kidney. The kidney stone may be stuck in your ureter (the tube that carries urine from your kidneys to your bladder). It also may be stuck ...

  16. Gender Distribution of Pediatric Stone Formers

    NASA Astrophysics Data System (ADS)

    Novak, Thomas E.; Trock, Bruce J.; Lakshmanan, Yegappan; Gearhart, John P.; Matlaga, Brian R.

    2008-09-01

    Recent epidemiologic evidence suggests that the gender prevalence among adult stone-formers is changing, with an increasing incidence of stone disease among women. No similar data have ever been reported for the pediatric stone-forming population. We performed a study to define the gender distribution among pediatric stone-formers using a large-scale national pediatric database. Our findings suggest that gender distribution among stone formers varies by age with male predominance in the first decade of life shifting to female predominance in the second decade. In contrast to adults, females in the pediatric population are more commonly affected by stones than are males. The incidence of pediatric stone disease appears to be increasing at a great rate in both sexes. Further studies should build on this hypothesis-generating work and define the effects of metabolic and environmental risk factors that may influence stone risk in the pediatric patient population

  17. Luserna Stone: A nomination for "Global Heritage Stone Resource"

    NASA Astrophysics Data System (ADS)

    Primavori, Piero

    2015-04-01

    Luserna Stone (Pietra di Luserna) is the commercial name of a grey-greenish leucogranitic orthogneiss, probably from the Lower Permian Age, that outcrops in the Luserna-Infernotto basin (Cottian Alps, Piedmont, NW Italy) on the border between the Turin and Cuneo provinces. Geologically speaking, it pertains to the Dora-Maira Massif that represents a part of the ancient European margin annexed to the Cottian Alps during the Alpine orogenesis; from a petrographic point of view, it is the metamorphic result of a late-Ercinian leucogranitic rock transformation. Lithological features and building applications allow the recognition of two main varieties: 1) a micro-augen gneiss with very regular schistosity planes with centimetric spacing and easy split workability, known as Splittable facies; 2) a micro-Augen gneiss characterized by lower schistosity and poor split, suitable for blocks cutting machines (diamond wires, gang-saws, traditional saws), known as Massive facies. A third, rare, white variety also exists, called "Bianchetta". Luserna stone extends over an area of approximately 50 km2, where more than fifty quarries are in operation, together with a relevant number of processing plants and artisanal laboratories. The stone is quarried and processed since almost the Middle Age, and currently represents one of the three most important siliceous production cluster in Italy (together with the Ossola and Sardegna Island granites). Some characteristics of this stone - such as the relevant physical-mechanical properties, an intrinsic versatility and its peculiar splittability - have made it one of the most widely used stone materials in Italy and in the countries surrounding the North Western border of Italy. Apart from its intrinsic geological, petrographic, commercial and technical properties, several issues related to the Luserna Stone are considered to be of relevant importance for its designation as a Global Heritage Stone Resource, such as the distinctive mark on the architecture and urban landscape of many areas in NW Italy, some quite peculiar applications (for ex.: the "so-called "loze" or "lose", for the traditional roofing in alpine buildings) and the related constructive culture, the presence of an Eco-Museum, the occurrence of a local Fair (Pietra & Meccanizzazione), and many other important aspects.

  18. Effect of Potassium Magnesium Citrate and Vitamin B-6 Prophylaxis for Recurrent and Multiple Calcium Oxalate and Phosphate Urolithiasis

    PubMed Central

    Shaik, Ahammad Basha; Bokkisam, Suneel

    2014-01-01

    Purpose To study the effects of long-term treatment with potassium magnesium citrate and vitamin B-6 prophylaxis (Urikind-KM6; 1,100-mg potassium citrate, 375-mg magnesium citrate, and 20-mg pyridoxine hydrochloride/5 mL) every 8 hours over 3 years. Materials and Methods A total of 247 patients with recurrent idiopathic hypocitraturia with or without hyperuricosuria and randomized controls were studied prospectively for 3 years. The total patients were divided into three groups. Control group 1 consisted of 61 patients (24.7%) who had moderate to severe hypocitraturia with or without hyperuricosuria and were recurrent stone formers but discontinued prophylaxis because of drug intolerance within 1 month of therapy. Control group 2 constituted 53 patients (21.5%) who were first-time stone formers and who had mild hypocitraturia with or without hyperuricosuria and were not put on prophylactic therapy and were followed for 3.160.08 years. Control group 3 constituted 133 patients (54.8%) who were recurrent stone formers who had moderate to severe hypocitraturia with or without hyperuricosuria and were put on prophylaxis therapy and were followed for 3.160.08 years. All patients were followed up at 6-month intervals. Results Potassium magnesium citrate prophylaxis produced a sustained increase in 24-hour urinary citrate excretion from initially low values (221.7913.39 mg/dL) to within normal to high limits (604.045.00 mg/dL) at the 6-month follow-up. Urinary pH rose significantly from 5.620.2 to 6.870.01 and was maintained at 6.870.01. The stone recurrence rate declined from 3.231.04 per patient per year to 0.350.47 per patient per year. Conclusions Potassium magnesium citrate prophylaxis was effective in reducing the recurrence of calcium oxalate and phosphate urolithiasis. PMID:24955227

  19. 21 CFR 862.1542 - Oxalate test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems 862... treatment of urinary stones or certain other metabolic disorders. (b) Classification. Class I...

  20. Of Mice and Men: Experimental Induction of Calcium Oxalate Nephrolithiasis in Mice

    PubMed Central

    Khan, Saeed R.; Glenton, Patricia A.

    2013-01-01

    Purpose Availability of various transgenic and knockout mice provides an excellent opportunity to better understand the pathophysiology of calcium oxalate (CaOx) stone disease. However attempts to produce CaOx nephrolithiasis in mice have not been very successful. We have hypothesized that CaOx nephrolithiasis in mice requires increasing the urinary excretion of calcium as well as oxalate and that experimentally induced hyperoxaluria alone is not sufficient. To provide evidence we induced hyperoxaluria by administering hyperoxaluria inducing agents to normocalciuric as well as hypercalciuric mice and investigated various aspects of nephrolithiasis. Materials and Methods Ethylene glycol (EG), glyoxylate (GOx) or hydroxyl proline (HLP) were administered through diet to male and female normocalciuric B6 mice as well as hypercalciuric Npt2a −/− mice for 4 weeks. 24 hour urine samples were collected on 0.3,7,14,21 and 28 days and analyzed for pH, creatinine, lactate dehydrogensae (LDH) calcium and oxalate. Kidneys were examined using light microscopy. Urine was examined for crystals using both light and scanning electron microscopy. Results Hypercalciuric mice on HLP did not tolerate the treatment and had to be sacrificed before 28 days. All mice receiving EG, GOx or HLP became hyperoxaluric and demonstrated CaOx crystalluria. None of the female mice, normo or hypercalciuric developed renal CaOx crystal deposits. All mice on Gox and some on EG developed CaOx nephrolithiais. Kidneys of all mice showed epithelial injury. Male mice particularly on GOx showed more renal injury and migration of inflammatory cells into the interstitium around the crystal deposits. Conclusions Results confirm that induction of hyperoxaluria alone is not sufficient for CaOx nephrolithiais in mice. Hypercalciuria is also required. Kidneys of male mice are more prone to injury than those of female mice and are susceptible to CaOx crystal deposition. Perhaps epithelial injury promotes crystal retention. Thus CaOx nephrolithiais in mice is gender dependent and requires both hypercalciuria and hyperoxaluria. PMID:20663521

  1. Optimizing Stone-free Rates With Ureteroscopy

    PubMed Central

    Reddy, Thanmaya G; Assimos, Dean G

    2015-01-01

    Ureteroscopy is being increasingly utilized in the treatment and management of patients with renal and ureteral stones. Improving stone-free rates with ureteroscopy decreases the need for ancillary procedures and improves patient outcomes and satisfaction. This article reviews contemporary literature regarding the efficacy of a wide range of currently available techniques for improving stone-free rates with this procedure. PMID:26543430

  2. Developing disease resistant stone fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stone fruit (Prunus spp.) (peach, nectarine, plum, apricot, cherry) and almonds are susceptible to a number of pathogens. These pathogens can cause extensive losses in the field, during transport and storage, and in the market. Breeding for disease resistance requires an extensive knowledge of the...

  3. Reaction of zirconium fluoride monohydrate and ammonium bifluoride; Its effect on fluoride glass preparation and quality

    SciTech Connect

    Ewing, K.J.; Sanghera, J.S.; Miklos, R.E.; Sachon, M.G.; Pietersen, L.; Hart, P.; Aggarwal, I. . Optical Sciences Div.)

    1989-08-01

    The products obtained from the room-temperature reaction of ammonium bifluoride and zirconium fluoride monohydrate are ammonium heptafluorozirconate ((NH/sub 4/)/sub 3/ZrF/sub 7/), liquid water, and hydrogen fluoride. This paper discusses ammonium bifluoride and zirconium fluoride monohydrate reacted prior to glass batching, producing dry ammonium heptafluorozirconate which was used to prepare a high-quality ZBLAN fluoride glass.

  4. Contribution of calcium oxalate to soil-exchangeable calcium

    USGS Publications Warehouse

    Dauer, Jenny M.; Perakis, Steven S.

    2013-01-01

    Acid deposition and repeated biomass harvest have decreased soil calcium (Ca) availability in many temperate forests worldwide, yet existing methods for assessing available soil Ca do not fully characterize soil Ca forms. To account for discrepancies in ecosystem Ca budgets, it has been hypothesized that the highly insoluble biomineral Ca oxalate might represent an additional soil Ca pool that is not detected in standard measures of soil-exchangeable Ca. We asked whether several standard method extractants for soil-exchangeable Ca could also access Ca held in Ca oxalate crystals using spike recovery tests in both pure solutions and soil extractions. In solutions of the extractants ammonium chloride, ammonium acetate, and barium chloride, we observed 2% to 104% dissolution of Ca oxalate crystals, with dissolution increasing with both solution molarity and ionic potential of cation extractant. In spike recovery tests using a low-Ca soil, we estimate that 1 M ammonium acetate extraction dissolved sufficient Ca oxalate to contribute an additional 52% to standard measurements of soil-exchangeable Ca. However, in a high-Ca soil, the amount of Ca oxalate spike that would dissolve in 1 M ammonium acetate extraction was difficult to detect against the large pool of exchangeable Ca. We conclude that Ca oxalate can contribute substantially to standard estimates of soil-exchangeable Ca in acid forest soils with low soil-exchangeable Ca. Consequently, measures of exchangeable Ca are unlikely to fully resolve discrepancies in ecosystem Ca mass balance unless the contribution of Ca oxalate to exchangeable Ca is also assessed.

  5. Perfluorobutyric acid and its monohydrate: a chirped pulse and cavity based fourier transform microwave spectroscopic study.

    PubMed

    Thomas, Javix; Serrato, Agapito; Lin, Wei; Jger, Wolfgang; Xu, Yunjie

    2014-05-12

    Rotational spectra of perfluorobutyric acid (PFBA) and its monohydrate were studied with a broadband chirped pulse and a narrow-band cavity based Fourier transform microwave spectrometer, and high-level ab initio calculations. Extensive conformational searches were performed for both the acid and its monohydrate at the MP2/6-311++G(2d,p) level of theory. Two and three conformers were predicted to exist for PFBA and its monohydrate, respectively. One set of rotational transitions was observed and assigned for each, PFBA and its monohydrate. Based on the measured broadband spectra, we confidently conclude that only one dominant conformer exists in each case. The orientation of the hydroxyl group in PFBA was determined by using isotopic analysis. Comparison of the observed transition intensities and the calculated electric dipole moment components allowed us to identify the most stable monohydrate conformation, which takes on an insertion hydrogen-bonding topology. Comparisons to the shorter chain analogues, that is, trifluoroacetic acid, perfluoropropionic acid, and their monohydrates, are made to elucidate the general trend in their conformational preference and binding topologies. PMID:24756992

  6. Development of an in vitro assay for the screening of substances capable of dissolving calcium oxalate crystals.

    PubMed

    Saso, L; Valentini, G; Leone, M G; Grippa, E; Silvestrini, B

    1998-01-01

    Despite the risk of kidney damage, lithotripsy is the usual way of treating calcium oxalate (CaOx) stones, the most common type of nephrolithiasis, because no effective chemolytic agents are available. However, the search of new calcium chelators, less toxic than the current ones, continues, and some of them could be tested in experimental models of nephrolithiasis, after their ability of dissolving CaOx crystals is verified. In this connection, we developed a simple assay that requires only inexpensive equipment available in most laboratories for the screening of substances potentially capable of dissolving CaOx crystals. In particular, we decided to investigate whether substances previously shown to inhibit CaOx precipitation were also capable of dissolving this salt. Briefly, CaOx tablets of highly reproducible weight (4.55 +/- 0.07 mg) were prepared by spinning, at high speed (16,000 g), microcentrifuge tubes in which 500 microl aliquots of 0.1 M sodium oxalate and 0.1 M calcium chloride at pH 6 were added. When these tablets were incubated overnight with solutions at different concentrations of EDTA, sodium citrate, manganese chloride, sodium sulfate, sodium chloride, malic acid, succinic acid and gluconic acid, a significant dissolving activity was observed for EDTA ( approximately 25% at 0.25 M), sodium citrate ( approximately 30% at 1 M) and manganese chloride ( approximately 20% at 0.5 M). A good linear correlation (r2 = 0.84, p < 0.05) was found between the affinity for calcium and the activity of EDTA, sodium citrate, sodium sulfate, malic acid, succinic acid and gluconic acid, indicating that these compounds act mainly by chelating the calcium ion. Instead, manganese was supposed to act by interacting with the oxalate ion. PMID:10364751

  7. Endoscopic management of upper urinary tract stones.

    PubMed Central

    Tolley, D. A.; Buist, T. A.

    1986-01-01

    In a two year period from March 1983, 157 patients with upper urinary tract stones were managed primarily by endoscopy. Of 90 patients with renal stones, extraction was achieved in 91% of patients with complete extraction in 76%. Of the remaining patients with ureteric stones, successful extraction was achieved in 75%. Ten patients required open surgery which was for failed extraction in 9. Morbidity is low with a mean hospital stay of 4.7 days for patients with kidney stones, and of 3.7 days for patients undergoing extraction of ureteric stones. Images Fig. 2 PMID:3954313

  8. DETERMINATION OF OXALATE ION DOPANT LEVEL IN POLYPYRROLE USING FT-IR

    PubMed Central

    Benally, Kristal J.; GreyEyes, Shawn D.; McKenzie, Jason T.

    2014-01-01

    A pellet method using standard addition and FT-IR was used to estimate oxalate ion doping levels in electrosynthesized polypyrrole. The method is useful for materials where removal of analyte from an insoluble material is problematic. Here, electrosynthesized oxalate doped polypyrrole is dispersed in potassium bromide. Spikes of sodium oxalate are added and the mixtures pressed into pellets. The oxalate carbonyl absorption peak is then used to quantify the amount of oxalate present in the polypyrrole. The mass fraction of oxalate dopant in polypyrrole was determined to be 0.4 0.1 % and coincides with the original synthesis solution composition. PMID:25598749

  9. Crystal structure of bis(pyridine betaine) hydrochloride monohydrate

    NASA Astrophysics Data System (ADS)

    Xiao-Ming, Chen; Mak, Thomas C. W.

    1990-04-01

    Bis(pyridine betaine) hydrochloride monohydrate, 2C 5H 5NCH 2COOHClH 2O, crystallizes in space group Pnna (No. 52), with a=15.623(3), b=19.707(3), c=5.069(1) , and Z=4. The structure has been refined to RF=0.067 for 1207 observed (| F0|>6?| F0|) Mo K? data. The carboxylate groups of a pair of pyridine betaine molecules are bridged by a proton to form a centrosymmetric dimer featuring a very strong hydrogen bond of length 2.436(6) . The crystal structure comprises a packing of such [(C 5H 5NCH 2COO) 2H] + moieties and hydrogen-bonded (Cl -{dH 2O} ?) zigzag chains running parallel to the c axis.

  10. Treatment Outcomes of Retrograde Intrarenal Surgery for Renal Stones and Predictive Factors of Stone-Free

    PubMed Central

    Lim, Soo Hyun; Jeong, Byong Chang; Seo, Seong Il; Jeon, Seong Soo

    2010-01-01

    Purpose The aim of this study was to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) for the treatment of renal stones and to analyze the predictive factors for stone-free. Materials and Methods We retrospectively reviewed the records of patients who underwent RIRS for renal stones from January 2000 to July 2009. We identified 66 RIRSs (63 patients with 3 bilateral renal stones) and collected data. Stone-free and success were respectively defined as no visible stones and clinically insignificant residual stones less than 3 mm on postoperative imaging; predictive factors for stone-free were evaluated. Results Of the 66 renal stones, 18 stones (27.3%) were located in the upper pole or midpole or renal pelvis and 48 (72.7%) in the lower pole with or without others, respectively. The mean cumulative stone burden was 168.9392.5 mm2. The immediate postoperative stone-free rate was 69.7%, and it increased to 72.7% at 1 month after surgery. The success rate was 80.3% both immediately after the operation and 1 month later. In the multivariate analysis, stone location except at the lower pole (p=0.049) and small cumulative stone burden (p=0.002) were significantly favorable predictive factors for the immediate postoperative stone-free rate. The overall complication rate was 6%. Conclusions RIRS is a safe and effective treatment for renal stones. The stone-free rate of RIRS was particularly high for renal stones with a small burden, except for those located in the lower pole. RIRS could be considered in selective patients with renal stones. PMID:21165199

  11. Prevention of hypercalciuria and stone-forming propensity during prolonged bedrest by alendronate

    NASA Technical Reports Server (NTRS)

    Ruml, L. A.; Dubois, S. K.; Roberts, M. L.; Pak, C. Y.

    1995-01-01

    The bone loss and hypercalciuria induced by immobilization or the decreased gravitational forces of space are well described. Using a model of bedrest immobilization, the ability of a potent aminobisphosphonate, alendronate, to avert hypercalciuria and stone-forming propensity was tested. Sixteen male subjects participated in a randomized, placebo-controlled trial in which they received either 20 mg of alendronate or placebo 2 weeks prior to and during 3 weeks of strict bedrest. Parameters of bone and calcium metabolism and urinary crystallization of stone-forming salts were measured before and at the end of bedrest. In the placebo group, bedrest increased urinary calcium (209 +/- 47 to 267 +/- 60 mg/day, p < 0.01) and the saturation of calcium phosphate. Before bedrest, the alendronate group had a significantly lower serum calcium (8.8 +/- 0.4 vs. 9.6 +/- 0.5 mg/dl, p < 0.01) and higher serum PTH (62.4 +/- 33.1 vs. 23.1 +/- 7.5 pg/ml, p < 0.01) compared with the placebo group. Moreover, the alendronate group had a lower urinary calcium (75 +/- 41 mg/day) and saturation of calcium oxalate and calcium phosphate. These effects of alendronate were sustained during bedrest. Following bedrest in the alendronate group, urinary calcium rose to 121 +/- 50 mg/day, a value less than that in the placebo group before or during bedrest. Similarly, urinary saturation of calcium oxalate and calcium phosphate rose with bedrest in the alendronate-treated patients but remained lower than values obtained in placebo-treated patients before or during bedrest. Alendronate inhibits bone mineral loss and averts the hypercalciuria and increased propensity for the crystallization of stone-forming calcium salts which occurs during 3 weeks of strict bedrest.

  12. [Determination of glyoxalate and oxalate by capillary zone electrophoresis].

    PubMed

    Guan, Jin; Wang, Huize; Ren, Liyan; Niu, Qiuling

    2012-01-01

    A method for the simultaneous determination of glyoxalate and oxalate by capillary zone electrophoresis (CZE) was developed. The influences of type, concentration and pH of the running buffer, and the applied voltage on separation were investigated. Glyoxalate and oxalate were separated within 11 min under the conditions of 20 mmol/L borax-5.5 mmol/L potassium hydrogen phthalate (pH 9.0), applied voltage of 20 kV, and detected wavelength of 212 nm. The calibration curves of glyoxalate and oxalate showed good linearity in the ranges of 0.8 -20 g/L and 1.2-20 g/L, respectively. The correlation coefficients were 0.999 3 and 0.997 5, respectively. The limits of detection for glyoxalate and oxalate were 0.2 and 0.4 g/L (S/N = 3), respectively. The average recoveries at three spiked levels were 98.3%-102.5% with acceptable relative standard deviations of 0.35%-0.61%. This method is simple, low cost and high performance. The method was successfully used for the determination of glyoxalate and oxalate in real samples, and the assay results were satisfactory. PMID:22667103

  13. Sulfuric Acid Monohydrate: Formation and Heterogeneous Chemistry in the Stratosphere

    NASA Technical Reports Server (NTRS)

    Zhang, Renyi; Leu, Ming-Taun; Keyser, Leon F.

    1995-01-01

    We have investigated some thermodynamic properties (i.e., freezing/melting points) and heterogeneous chemistry of sulfuric acid monohydrate (SAM, H2SO4.H2O), using a fast flow reactor coupled to a quadrupole mass spectrometer. The freezing point observations of thin liquid sulfuric acid films show that for acid contents between 75 and 85 wt % the monohydrate crystallizes readily at temperatures between 220 and 240 K on a glass substrate. Once formed, SAM can be thermodynamically stable in the H2O partial pressure range of (1-4) x 10(exp -4) torr and in the temperature range of 220-240 K. For a constant H2O partial pressure, lowering the temperature causes SAM to melt when the temperature and water partial pressure conditions are out of its stability regime. The reaction probability measurements indicate that the hydrolysis of N2O5 is significantly suppressed owing to the formation of crystalline SAM: The reaction probability on water-rich SAM (with higher relative humidity, or RH) is of the order of 10(exp -3) at 210 K and decreases by more than an order of magnitude for the acid-rich form (with lower RH). The hydrolysis rate of ClONO2 on water-rich SAM is even smaller, of the order of 10(exp -4) at 195 K. These reported values on crystalline SAM are much smaller than those on liquid solutions. No enhancement of these reactions is observed in the presence of HCl vapor at the stratospheric concentrations. In addition, Brunauer, Emmett, and Teller analysis of gas adsorption isotherms and photomicrography have been performed to characterize the surface roughness and porosities of the SAM substrate. The results suggest the possible formation of SAM in some regions of the middle- or low-latitude stratosphere and, consequently, much slower heterogeneous reactions on the frozen aerosols.

  14. Dielectric relaxation study on tramadol monohydrate and its hydrochloride salt.

    PubMed

    Kaminski, K; Kaminska, E; Adrjanowicz, K; Grzybowiska, K; Wlodarczyk, P; Paluch, M; Burian, A; Ziolo, J; Lepek, P; Mazgalski, J; Sawicki, W

    2010-01-01

    Dielectric relaxation measurements as well as differential scanning calorimetry and X-ray diffraction investigations were performed on tramadol monohydrate and its hydrochloride salt. Examined samples do not crystallize during cooling and in consequence they reach the glassy state. In the case of the hydrochloride tramadol we are able to monitor alpha-relaxation process despite large contribution of dc conductivity to the loss spectra. It is the first such study on the salt of the drug. Up to now the dielectric spectroscopy has been regarded as useless in measuring such kind of API (active pharmaceutical ingredient). In this paper we also made some suggestions about the nature of the secondary relaxations in the amorphous tramadol monohydrate and its salt. The knowledge about the molecular mechanisms, which govern the observed secondary relaxations seems to be the key in predicting the stability of the amorphous form of the examined API. Finally additional dissolving measurements on the amorphous and crystal tramadol hydrochloride were performed. As a result we understood that dissolution properties of the amorphous form of the considered drug are comparable to those of crystalline one. However, we have found out that amorphous tramadol hydrochloride has greater ability to form tablets than its crystalline equivalent. This finding shows that amorphous drugs can be alternative even for the freely solved pharmaceuticals such as tramadol hydrochloride, because the former one has better ability to form tablets. It implies that during tabletting of the amorphous drugs there is no need to use any excipients and chemicals improving compaction properties of the API. PMID:19475556

  15. Structure, hydrogen bonding and thermal expansion of ammonium carbonate monohydrate.

    PubMed

    Fortes, A Dominic; Wood, Ian G; Alf, Dario; Hernndez, Eduardo R; Gutmann, Matthias J; Sparkes, Hazel A

    2014-12-01

    We have determined the crystal structure of ammonium carbonate monohydrate, (NH4)2CO3H2O, using Laue single-crystal diffraction methods with pulsed neutron radiation. The crystal is orthorhombic, space group Pnma (Z = 4), with unit-cell dimensions a = 12.047?(3), b = 4.453?(1), c = 11.023?(3)? and V = 591.3?(3)?(3) [?calc = 1281.8?(7)?kg?m(-3)] at 10?K. The single-crystal data collected at 10 and 100?K are complemented by X-ray powder diffraction data measured from 245 to 273?K, Raman spectra measured from 80 to 263?K and an athermal zero-pressure calculation of the electronic structure and phonon spectrum carried out using density functional theory (DFT). We find no evidence of a phase transition between 10 and 273?K; above 273?K, however, the title compound transforms first to ammonium sesquicarbonate monohydrate and subsequently to ammonium bicarbonate. The crystallographic and spectroscopic data and the calculations reveal a quite strongly hydrogen-bonded structure (EHB ? 30-40?kJ?mol(-1)), on the basis of H...O bond lengths and the topology of the electron density at the bond critical points, in which there is no free rotation of the ammonium cation at any temperature. The barrier to free rotation of the ammonium ions is estimated from the observed librational frequency to be ??36?kJ?mol(-1). The c-axis exhibits negative thermal expansion, but the thermal expansion behaviour of the a and b axes is ormal. PMID:25449618

  16. Structure, hydrogen bonding and thermal expansion of ammonium carbonate monohydrate

    PubMed Central

    Fortes, A. Dominic; Wood, Ian G.; Alfè, Dario; Hernández, Eduardo R.; Gutmann, Matthias J.; Sparkes, Hazel A.

    2014-01-01

    We have determined the crystal structure of ammonium carbonate monohydrate, (NH4)2CO3·H2O, using Laue single-crystal diffraction methods with pulsed neutron radiation. The crystal is orthorhombic, space group Pnma (Z = 4), with unit-cell dimensions a = 12.047 (3), b = 4.453 (1), c = 11.023 (3) Å and V = 591.3 (3) Å3 [ρcalc = 1281.8 (7) kg m−3] at 10 K. The single-crystal data collected at 10 and 100 K are complemented by X-ray powder diffraction data measured from 245 to 273 K, Raman spectra measured from 80 to 263 K and an athermal zero-pressure calculation of the electronic structure and phonon spectrum carried out using density functional theory (DFT). We find no evidence of a phase transition between 10 and 273 K; above 273 K, however, the title compound transforms first to ammonium sesquicarbonate monohydrate and subsequently to ammonium bicarbonate. The crystallographic and spectroscopic data and the calculations reveal a quite strongly hydrogen-bonded structure (E HB ≃ 30–40 kJ mol−1), on the basis of H⋯O bond lengths and the topology of the electron density at the bond critical points, in which there is no free rotation of the ammonium cation at any temperature. The barrier to free rotation of the ammonium ions is estimated from the observed librational frequency to be ∼ 36 kJ mol−1. The c-axis exhibits negative thermal expansion, but the thermal expansion behaviour of the a and b axes is ormal. PMID:25449618

  17. Systemic implications of urinary stone disease

    PubMed Central

    Kovshilovskaya, Bogdana; Miller, Joe; Stoller, Marshall L.

    2012-01-01

    Urinary stone disease is the third most common condition affecting the urinary tract. It contributes to a great deal of morbidity for both men and women, and cost the United States (US) over 5.3 billion dollars in 2000 alone. Moreover, it is associated with systemic diseases such as hypertension, diabetes, and other components of the metabolic syndrome. Reciprocally, these systemic diseases may be contributing to the rising incidence in urinary stone disease. Previously described mechanisms of stone formation attribute stone development and growth to the urinary milieu. While this may partly influence the process, it cannot account for the associations between systemic diseases and stones observed in large community-based studies. Here we present a review of the evidence demonstrating a link between urinary stone disease and components of the metabolic syndrome. We believe a vascular etiology for the initiation of urinary stones may tie these processes together. PMID:26816692

  18. Characterization of Urinary Stone Composition by Use of Third-Generation Dual-Source Dual-Energy CT With Increased Spectral Separation

    PubMed Central

    Duan, Xinhui; Li, Zhoubo; Yu, Lifeng; Leng, Shuai; Halaweish, Ahmed F.; Fletcher, Joel G.; McCollough, Cynthia H.

    2015-01-01

    OBJECTIVE The purpose of this phantom study was to determine the utility of a third-generation dual-source CT scanner with increased dual-energy spectral separation in differentiating urinary stone composition. MATERIALS AND METHODS Eighty-seven urinary stones from humans were scanned in 35-, 40-, 45-, and 50-cm wide anthropomorphic phantoms with a third-generation dual-source scanner (system A) with a high-energy beam of 150 kV plus 0.6-mm tin filtration (Sn). The low-energy data were acquired at 70, 80, 90, and 100 kV. A second-generation dual-source scanner (system B) was used to acquire data at 140 kV plus 0.4-mm Sn for the high-energy and 80 or 100 kV for the low-energy images. Volume CT dose index was matched for a given phantom size. CT number ratios were calculated and used to differentiate uric acid from nonuric acid stones and oxalate from apatite stones in an ROC analysis. RESULTS The area under the curve (AUC) of the ROC curve for uric acid versus nonuric acid stones increased for large phantoms. For example, for imaging of the 45-cm wide phantom with system A at the 100- and 150-kV Sn low- and high-energy combination, the AUC was 0.99, whereas for system B at the 100- and 140-kV Sn combination, the AUC was 0.86. At each phantom size and for all energy combinations, the AUC values for oxalate versus apatite stones were higher for system A than they were for any energy combination for system B. CONCLUSION Compared with use of second-generation dual-source CT, use of third-generation dual-source CT at the energy combination of 100 and 150 kV Sn improved classification of urinary stones across a wide range of phantom sizes and increased the ability to differentiate oxalate from apatite stones. PMID:26587926

  19. Changes in oxalate and some mineral concentrations of Setaria sphacelata under cutting and uncutting conditions.

    PubMed

    Rahman, M M; Tateyama, M; Niimi, M; Abdullah, R B; Khadijah, W E Wan; Kawamura, O

    2014-04-01

    Oxalate concentration in forage plants is important, because it results mineral deficiency in ruminants. Data on oxalate concentration in forage plants in conjunction with cutting and uncutting conditions throughout the growing period are limited. This study was aimed to investigate the changes in oxalate and some mineral concentrations of setaria (Setaria sphacelata). The plants were harvested at different stages (vegetative, boot, pre-flowering, flowering and seed) of maturity and at about 50 cm in length of regrowth (second to sixth cuttings) for evaluation of soluble oxalate, insoluble oxalate and some mineral concentrations. Soluble oxalate and total oxalate concentrations, as well as mineral concentrations, decreased with advancing maturity. Both oxalate concentrations (soluble or insoluble) were higher in leaf compared to stem. Soluble oxalate and total oxalate concentrations of regrowth were the highest at third cutting and lowest at sixth cutting. Insoluble oxalate concentration of regrowth was almost similar in all cuttings, except for the sixth cutting. The highest concentrations of potassium, sodium and magnesium of regrowth were observed at third cutting, while the highest concentration of calcium was observed at sixth cutting. A relationship between oxalate and mineral concentrations was partially observed. Results suggest that cutting materials of setaria from June to October could achieve oxalate levels that are toxic to ruminants. PMID:25911853

  20. Elimination of oxalate by fat sand rats (Psammomys obesus): wild and laboratory-bred animals compared.

    PubMed

    Palgi, Niv; Taleisnik, Hanna; Pinshow, Berry

    2008-02-01

    Wild fat sand rats (Psammomys obesus) can feed exclusively on plants containing much oxalate, but little calcium; oxalate intake may exceed 300 mg/d, while calcium intake is approximately 30 mg/day. By contrast, for generations, laboratory bred P. obesus have been fed a low-oxalate (<100 mg/day), high-calcium (approximately 150 mg/day) rodent chow. We compared oxalate intake and excretion between wild and laboratory-bred animals, both fed the natural high-oxalate diet, to determine whether these different dietary histories are reflected in the animal's ability to eliminate dietary oxalate. Since both wild and laboratory-bred P. obesus harbor intestinal oxalate-degrading bacteria, we predicted that their oxalate intake and excretion would be similar. Indeed, we found no significant differences in oxalate intake or excretion between the groups fed either saltbush or alfalfa (p>0.05). However, due to the differences in dietary calcium intake between the two diets, in both groups only part (23-25%) of the ingested oxalate was excreted when the animals were fed the oxalate-rich saltbush, yet most (87-90%) was excreted when feeding on calcium-rich alfalfa. Thus, even after generations of feeding on a commercial low-oxalate diet, fat sand rats maintain intestinal oxalate-degrading bacteria that appear to increase in number and activity when presented with their natural diet. PMID:18187353

  1. Crystal structure of di-methyl-ammonium hydrogen oxalate hemi(oxalic acid).

    PubMed

    Diallo, Waly; Gueye, Ndongo; Crochet, Aurlien; Plasseraud, Laurent; Cattey, Hlne

    2015-05-01

    Single crystals of the title salt, Me2NH2 (+)HC2O4 (-)0.5H2C2O4, were isolated as a side product from the reaction involving Me2NH, H2C2O4 and Sn(n-Bu)3Cl in a 1:2 ratio in methanol or by the reaction of the (Me2NH2)2C2O4 salt and Sn(CH3)3Cl in a 2:1 ratio in ethanol. The asymmetric unit comprises a di-methyl-ammonium cation (Me2NH2 (+)), an hydrogenoxalate anion (HC2O4 (-)), and half a mol-ecule of oxalic acid (H2C2O4) situated about an inversion center. From a supra-molecular point of view, the three components inter-act together via hydrogen bonding. The Me2NH2 (+) cations and the HC2O4 (-) anions are in close proximity through bifurcated N-H?(O,O) hydrogen bonds, while the HC2O4 (-) anions are organized into infinite chains via O-H?O hydrogen bonds, propagating along the a-axis direction. In addition, the oxalic acid (H2C2O4) mol-ecules play the role of connectors between these chains. Both the carbonyl and hydroxyl groups of each diacid are involved in four inter-molecular inter-actions with two Me2NH2 (+) and two HC2O4 (-) ions of four distinct polymeric chains, via two N-H?O and two O-H?O hydrogen bonds, respectively. The resulting mol-ecular assembly can be viewed as a two-dimensional bilayer-like arrangement lying parallel to (010), and reinforced by a C-H?O hydrogen bond. PMID:25995858

  2. Functional dissection of a eukaryotic dicistronic gene: transgenic stonedB, but not stonedA, restores normal synaptic properties to Drosophila stoned mutants.

    PubMed Central

    Estes, Patricia S; Jackson, Taryn C; Stimson, Daniel T; Sanyal, Subhabrata; Kelly, Leonard E; Ramaswami, Mani

    2003-01-01

    The dicistronic Drosophila stoned mRNA produces two proteins, stonedA and stonedB, that are localized at nerve terminals. While the stoned locus is required for synaptic-vesicle cycling in neurons, distinct or overlapping synaptic functions of stonedA and stonedB have not been clearly identified. Potential functions of stoned products in nonneuronal cells remain entirely unexplored in vivo. Transgene-based analyses presented here demonstrate that exclusively neuronal expression of a dicistronic stoned cDNA is sufficient for rescue of defects observed in lethal and viable stoned mutants. Significantly, expression of a monocistronic stonedB trangene is sufficient for rescuing various phenotypic deficits of stoned mutants, including those in organismal viability, evoked transmitter release, and synaptotagmin retrieval from the plasma membrane. In contrast, a stonedA transgene does not alleviate any stoned mutant phenotype. Novel phenotypic analyses demonstrate that, in addition to regulation of presynaptic function, stoned is required for regulating normal growth and morphology of the motor terminal; however, this developmental function is also provided by a stonedB transgene. Our data, although most consistent with a hypothesis in which stonedA is a dispensable protein, are limited by the absence of a true null allele for stoned due to partial restoration of presynaptic stonedA by transgenically provided stonedB. Careful analysis of the effects of the monocistronic transgenes together and in isolation clearly reveals that the presence of presynaptic stonedA is dependent on stonedB. Together, our findings improve understanding of the functional relationship between stonedA and stonedB and elaborate significantly on the in vivo functions of stonins, recently discovered phylogenetically conserved stonedB homologs that represent a new family of "orphan" medium (mu) chains of adaptor complexes involved in vesicle formation. Data presented here also provide new insight into potential mechanisms that underlie translation and evolution of the dicistronic stoned mRNA. PMID:14504226

  3. Effect of Tribulus terrestris on oxalate metabolism in rats.

    PubMed

    Sangeeta, D; Sidhu, H; Thind, S K; Nath, R

    1994-10-01

    This study concerns the effect of an aqueous extract of Tribulus terrestris on the metabolism of oxalate in male rats fed sodium glycolate. Glycolate feeding resulted in hyperoxaluria as well as increased activities of oxalate synthesizing enzymes of the liver i.e. glycolate oxidase (GAO), glycolate dehydrogenase (GAD) and lactate dehydrogenase (LDH), and decreased kidney LDH activity. T. terrestris administration to sodium glycolate fed rats produced a significant decrease in urinary oxalate excretion, and a significant increase in urinary glyoxylate excretion, as compared to sodium glycolate fed animals. The supplementation of T. terrestris with sodium glycolate also caused a reduction in liver GAO and GAD activities, whereas liver LDH activity remained unaltered. The isoenzyme pattern of kidney LDH revealed that normalization of kidney LDH by T. terrestris feeding was mainly due to an increase in the LDH 5 fraction. The LDH 1 isoenzyme remained unchanged in all the groups. PMID:7853865

  4. Characterization of wheat germin (oxalate oxidase) expressed by Pichia pastoris

    SciTech Connect

    Pan, Heng-Yen; Whittaker, Mei M.; Bouveret, Romaric; Berna, Anne; Bernier, Francois; Whittaker, James W. . E-mail: jim@ebs.ogi.edu

    2007-05-18

    High-level secretory expression of wheat (Triticum aestivum) germin/oxalate oxidase was achieved in Pichia pastoris fermentation cultures as an {alpha}-mating factor signal peptide fusion, based on the native wheat cDNA coding sequence. The oxalate oxidase activity of the recombinant enzyme is substantially increased (7-fold) by treatment with sodium periodate, followed by ascorbate reduction. Using these methods, approximately 1 g (4 x 10{sup 4} U) of purified, activated enzyme was obtained following eight days of induction of a high density Pichia fermentation culture, demonstrating suitability for large-scale production of oxalate oxidase for biotechnological applications. Characterization of the recombinant protein shows that it is glycosylated, with N-linked glycan attached at Asn47. For potential biomedical applications, a nonglycosylated (S49A) variant was also prepared which retains essentially full enzyme activity, but exhibits altered protein-protein interactions.

  5. The influence of scale inhibitors on calcium oxalate

    SciTech Connect

    Gill, J.S.

    1999-11-01

    Precipitation of calcium oxalate is a common occurrence in mammalian urinary tract deposits and in various industrial processes such as paper making, brewery fermentation, sugar evaporation, and tannin concentration. Between pH 3.5 to 4.5 the driving force for calcium oxalate precipitation increases almost by three fold. It is a complicated process to predict both the nature of a deposit and at which stage of a multi-effect evaporator a particular mineral will deposit, as this depends on temperature, pH, total solids, and kinetics of mineralization. It is quite a challenge to inhibit calcium oxalate precipitation in the pH range of 4--6. Al{sup 3+} ions provide excellent threshold inhibition in this pH range and can be used to augment traditional inhibitors such as polyphosphates and polycarboxylates.

  6. Calcium oxalate crystals induce renal inflammation by NLRP3-mediated IL-1β secretion

    PubMed Central

    Mulay, Shrikant R.; Kulkarni, Onkar P.; Rupanagudi, Khader V.; Migliorini, Adriana; Darisipudi, Murthy N.; Vilaysane, Akosua; Muruve, Daniel; Shi, Yan; Munro, Fay; Liapis, Helen; Anders, Hans-Joachim

    2012-01-01

    Nephrocalcinosis, acute calcium oxalate (CaOx) nephropathy, and renal stone disease can lead to inflammation and subsequent renal failure, but the underlying pathological mechanisms remain elusive. Other crystallopathies, such as gout, atherosclerosis, and asbestosis, trigger inflammation and tissue remodeling by inducing IL-1β secretion, leading us to hypothesize that CaOx crystals may induce inflammation in a similar manner. In mice, intrarenal CaOx deposition induced tubular damage, cytokine expression, neutrophil recruitment, and renal failure. We found that CaOx crystals activated murine renal DCs to secrete IL-1β through a pathway that included NLRP3, ASC, and caspase-1. Despite a similar amount of crystal deposits, intrarenal inflammation, tubular damage, and renal dysfunction were abrogated in mice deficient in MyD88; NLRP3, ASC, and caspase-1; IL-1R; or IL-18. Nephropathy was attenuated by DC depletion, ATP depletion, or therapeutic IL-1 antagonism. These data demonstrated that CaOx crystals trigger IL-1β–dependent innate immunity via the NLRP3/ASC/caspase-1 axis in intrarenal mononuclear phagocytes and directly damage tubular cells, leading to the release of the NLRP3 agonist ATP. Furthermore, these results suggest that IL-1β blockade may prevent renal damage in nephrocalcinosis. PMID:23221343

  7. Calcium oxalate crystals induce renal inflammation by NLRP3-mediated IL-1? secretion.

    PubMed

    Mulay, Shrikant R; Kulkarni, Onkar P; Rupanagudi, Khader V; Migliorini, Adriana; Darisipudi, Murthy N; Vilaysane, Akosua; Muruve, Daniel; Shi, Yan; Munro, Fay; Liapis, Helen; Anders, Hans-Joachim

    2013-01-01

    Nephrocalcinosis, acute calcium oxalate (CaOx) nephropathy, and renal stone disease can lead to inflammation and subsequent renal failure, but the underlying pathological mechanisms remain elusive. Other crystallopathies, such as gout, atherosclerosis, and asbestosis, trigger inflammation and tissue remodeling by inducing IL-1? secretion, leading us to hypothesize that CaOx crystals may induce inflammation in a similar manner. In mice, intrarenal CaOx deposition induced tubular damage, cytokine expression, neutrophil recruitment, and renal failure. We found that CaOx crystals activated murine renal DCs to secrete IL-1? through a pathway that included NLRP3, ASC, and caspase-1. Despite a similar amount of crystal deposits, intrarenal inflammation, tubular damage, and renal dysfunction were abrogated in mice deficient in MyD88; NLRP3, ASC, and caspase-1; IL-1R; or IL-18. Nephropathy was attenuated by DC depletion, ATP depletion, or therapeutic IL-1 antagonism. These data demonstrated that CaOx crystals trigger IL-1?-dependent innate immunity via the NLRP3/ASC/caspase-1 axis in intrarenal mononuclear phagocytes and directly damage tubular cells, leading to the release of the NLRP3 agonist ATP. Furthermore, these results suggest that IL-1? blockade may prevent renal damage in nephrocalcinosis. PMID:23221343

  8. E057: Renal Stone Risk Assessment During Space Flight: Assessment and Countermeasure Validation

    NASA Technical Reports Server (NTRS)

    Whitson, Peggy A.; Pietrzyk, Robert A.; Jones, Jeffrey A.; Sams, Clarence F.

    2001-01-01

    Exposure to the microgravity environment results in many metabolic and physiological changes to humans. Body fluid volumes, electrolyte levels, and bone and muscle undergo changes as the human body adapts to the weightless environment. Changes in the urinary biochemistry occur as early as flight day 3-4 in the short duration Shuttle crewmembers. Significant decreases were observed both in fluid intake and urinary output. Other significant changes were observed in the urinary pH, calcium, potassium and uric acid levels. During Shuttle missions, the risk of calcium oxalate stone formation increased early in the flight, continued at elevated levels throughout the flight and remained in the increased risk range on landing day. The calcium phosphate risk was significantly increased early in-flight and remained significantly elevated throughout the remainder of the mission. Results from the long duration Shuttle-Mir missions followed a similar trend. Most long duration crewmembers demonstrated increased urinary calcium levels despite lower dietary calcium intake. Fluid intake and urine volumes were significantly lower during the flight than during the preflight. The calcium oxalate risk was increased relative to the preflight levels during the early in-flight period and continued in the elevated risk range for the remainder of the space flight and through two weeks postflight. Calcium phosphate risk for these long duration crewmembers increased during flight and remained in the increased risk range throughout the flight and following landing. The complexity, expense and visibility of the human space program require that every effort be made to protect the health of the crewmembers and ensure the success of the mission. Results from our early investigations clearly indicate that exposure to the microgravity environment of space significantly increases the risk of renal stone formation. The early studies have indicated specific avenues for development of countermeasures for the increased renal stone risk observed during and following space flight. Increased hydration and implementation of pharmacological countermeasures are being tested for their efficacy in mitigating the in-flight risk of renal stones. Maintaining the health and well-being of crewmembers during space flight requires a means of minimizing potential detrimental health effects of microgravity. The formation of a renal stone during flight obviously has severe consequences for the affected crewmember as well as the success of the mission.

  9. Determination of chemical composition of gallbladder stones and their association with induction of cholangiocarcinoma.

    PubMed

    Hussain, Saad Muhmood; Al-Jashamy, Karim Alwan

    2013-01-01

    Gallstone disease is a major surgical problem in many populations; it is probably related to diet, especially excessive consumption of meat. The objective of this study was to determine the chemical composition of gallstones and their association with neoplastic changes including cholangiocarcinomas in cholecystectomised patients. The chemical composition of gallstones from 40 patients (8 males and 32 females) was analyzed. This is a prospective study performed in Baquba teaching hospital in the period from 1/10/2012 to 1/1/2013 in which we collected the gallstones for the patients who underwent cholecystectomy, whether open or laparoscopic. The stones were classified according to their chemical composition as a mixed stones (MS), and examined using a stone analysis set (chemical qualitative method) for calcium, magnesium, phosphate, uric acid and oxalate which was used reagent for qualitative determination of main individual components of stones. The results of this study showed the highest incidence of gallstones in the age group 40-49 was 13 cases followed by 11, 8 and 4 cases for age groups 30-39, 50-59, 20-29 and 60 and above, respectively. The chemical analysis showed the majority of gallstones were mixed, 38 containing calcium followed by 37 cases with uric acid, 28 with magnesium, and 25 and 22 stones with oxalate and phosphate, respectively. Microscopically, we confirmed neoplastic changes (17.5%) as cholangiocarcinomas (CCCs) (7.55%) and dysplastic cells of carcinoma in situ in 4 (10%), 31 (77.5%) cases were chronic cholecystitis and 2 (5%) cases were acute cholecystitis with empyema out of bile duct disorders patients. In conclusion, majority of cases had mixed gallstones that involved five and four of inorganic chemicals of calcium, magnesium and phosphate, the highest incidence of gallstones in age group 40-49 years old was 13 cases, and neoplastic changes were confirmed (17.5%) including CCCs, (7.5%) and dysplastic cells of carcinoma in situ (10%), while 31 (77.5%) cases were chronic cholecystitis. PMID:24377514

  10. Intrahepatic biliary stones in children.

    PubMed

    Enriquez, G; Lucaya, J; Allende, E; Garcia-Pea, P

    1992-01-01

    Intrahepatic biliary stones in seven non-Oriental patients were studied in all by sonography, in four patients by computed tomography and in four patients by percutaneous transhepatic cholangiography. For patients had extrahepatic biliary atresia treated with portoenterostomies, one patient had undergone partial liver transplantation and of the remaining two, one had cystic fibrosis and the other immunodeficiency syndrome. All sonograms were abnormal and showed echogenic foci within the liver, with or without associated signs of biliary tract dilatation. CT confirmed the biliary tract dilatation yet calculi were identified in one patient only. PTC was particularly helpful in the patient with immunodeficiency in whom features typical of sclerosing cholangitis were found. This report emphasizes the variable radiological appearance of bile stones which to our knowledge have rarely been described in children with entities other than Oriental cholangitis. PMID:1523054

  11. The Matariki Stone of Rapanui

    NASA Astrophysics Data System (ADS)

    Hockey, T. A.

    2005-12-01

    Anthropological studies of Rapanui (Easter Island) are valuable insofar as the island's remoteness allowed its culture to develop independently until western contact. Of special importance to cultural astronomers is the indigenous inhabitants' expressed interest in the sky, through lore, monumental architecture, and rock art. 1 The Matariki Stone is a unique basaltic boulder found on Rapanui; my analysis of it is the result of in situ investigation (2000). The boulder is 1 m x 1.5 m x 2 m in approximate size and weighs in excess of 10,000 kg. According to local informants, at least six cupules, averaging 6 cm in diameter and 5 cm in depth, were placed in it prior to western contact with the island and prior to transport to the boulder's present location. Information about the Matariki Stone's original setting, orientation, and context is lost. "Matariki" means "Pleiades" (or, more generally, a group of stars). However, the pattern of the Matariki Stone cupules strongly resembles another familiar asterism of third-magnitude stars. 2 These zodiac stars were placed significantly in the Rapanui sky of 1500 CE. Yet no local ethnographic evidence mentions these stars, nor is association with these stars and other regional cultures (e. g., Australian aboriginal and Mayan) compelling. 3 Moreover, there is no Polynesian tradition of constellation depiction in rock art at all, whereas the Pleiades figure prominently in that culture's oral tradition. 4 Thus, the Matariki Stone remains a conundrum. 1 Liller, William. The Ancient Solar Observatories of Rapanui: The Archaeoastronomy of Easter Island. (1993) 2 Hockey, Thomas and Hoffman, Alice. "An Archaeoastronomical Investigation: Does A Constellation Pattern Appear in Rapanui Rock Art?" Rapa Nui Journal. 14, no. 3. (2000) 3 For example, Kelly, David H. and Milone, Eugene F. Exploring Ancient Skies: An Encyclopedic Survey of Archaeoastronomy. (2005) 4 For example, Makemson, Maude. The Morning Star Rises. (1941)

  12. Greco-Roman Stone Disease

    NASA Astrophysics Data System (ADS)

    Moran, Michael E.; Ruzhansky, Katherine

    2008-09-01

    Greek and Roman thought had a profound influence upon Western medical practice. From the fall of the Greek civilization to the fall of the Roman, remarkable progress of our understanding of human anatomy and physiology occurred. Here we review the attempts of Greek and Roman thinkers to develop the first understanding of the pathophysiology of urolithiasis, its epidemiology, differential diagnosis of renal versus bladder stones, medications for both colic and prevention, the role of familial syndromes, and dietary management.

  13. Growth retardation of calcium oxalate by sodium copper chlorophyllin.

    PubMed

    Desjardins, A; Tawashi, R

    1978-01-01

    Earlier reports from our laboratories described the inhibitory effect of Mg++ and pyrophosphate on the dissolution and growth of calcium oxalate. In this report, growth of Ca oxalate in presence of very low concentration of chlorophyllin was followed by the Coulter counter and a multichannel analyser. The effect of chlorophyllin concentration on crystal formation was studied at different levels of supersaturation. A concentration of 0.1 microgram/ml produced a remarkable retardation of the induction period and the growth rate. The findings obtained in this study are discussed in the light of the crystal poisoning theory. Comparison was made between chlorophyllin and other growth inhibitors. PMID:668744

  14. Acute renal failure following oxalic acid poisoning: a case report

    PubMed Central

    2012-01-01

    Oxalic acid poisoning is being recognized as an emerging epidemic in the rural communities of Sri Lanka as it is a component of locally produced household laundry detergents. Herein we describe a case of a 32?year old female, presenting after direct ingestion of oxalic acid. She then went on to develop significant metabolic acidosis and acute renal failure, requiring dialysis. Renal biopsy revealed acute tubulointerstitial nephritis associated with diffuse moderate acute tubular damage with refractile crystals in some of the tubules. The patient symptomatically improved with haemodialysis and renal functions subsequently returned to normal. PMID:22978510

  15. Hydrogen Bond Symmetrization in Glycinium Oxalate under Pressure.

    PubMed

    Bhatt, Himal; Murli, Chitra; Mishra, A K; Verma, Ashok K; Garg, Nandini; Deo, M N; Chitra, R; Sharma, Surinder M

    2016-02-01

    The study of hydrogen bonds near symmetrization limit at high pressures is of importance to understand proton dynamics in complex bio-geological processes. We report here the evidence of hydrogen bond symmetrization in the simplest amino acid-carboxylic acid complex, glycinium oxalate, at moderate pressures of 8 GPa using in-situ infrared and Raman spectroscopic investigations combined with first-principles simulations. The dynamic proton sharing between semioxalate units results in covalent-like infinite oxalate chains. At pressures above 12 GPa, the glycine units systematically reorient with pressure to form hydrogen-bonded supramolecular assemblies held together by these chains. PMID:26730739

  16. Acute renal failure following oxalic acid poisoning: a case report.

    PubMed

    Dassanayake, Uditha; Gnanathasan, Christeine Ariaranee

    2012-01-01

    Oxalic acid poisoning is being recognized as an emerging epidemic in the rural communities of Sri Lanka as it is a component of locally produced household laundry detergents. Herein we describe a case of a 32?year old female, presenting after direct ingestion of oxalic acid. She then went on to develop significant metabolic acidosis and acute renal failure, requiring dialysis. Renal biopsy revealed acute tubulointerstitial nephritis associated with diffuse moderate acute tubular damage with refractile crystals in some of the tubules. The patient symptomatically improved with haemodialysis and renal functions subsequently returned to normal. PMID:22978510

  17. Epidemiologic insights into pediatric kidney stone disease.

    PubMed

    Matlaga, Brian R; Schaeffer, Anthony J; Novak, Thomas E; Trock, Bruce J

    2010-12-01

    The epidemiology of pediatric kidney stone has not yet been as rigorously defined as that of adult kidney stone disease. Herein, we review our recent epidemiologic works characterizing pediatric stone disease using the Kids' Inpatient Database (KID). Specifically we investigated the age and gender distribution of pediatric kidney stone disease, changes in disease prevalence over time, and medical comorbidities associated with this disorder. We identified patients by International Classification of Disease 9th Edition (ICD-9) codes for renal and ureteral calculi as the primary diagnosis. Medical comorbidities were identified using specific comorbidity software. Statistical comparisons between children with and without stone disease were performed. In the first decade of life, stone disease was more prevalent among males than females; however, in the second decade of life females were more commonly affected. Of note, there was a significant increase in treated stone disease across both genders between 1997 and 2003. We also found that the risk of kidney stone diagnosis in children younger than 6 years of age was significantly associated with hypertension and diabetes mellitus. The gender distribution among pediatric stone formers varies significantly by age, although overall females have a greater prevalence than males. There is also a strong association of stone disease and both diabetes and hypertension, although this was only observed in children less than 6 years of age. Taken all together, these findings suggest that urolithiasis in the young child is a complex systemic disease process. PMID:20967433

  18. Focused ultrasound guided relocation of kidney stones

    PubMed Central

    Abrol, Nitin; Kekre, Nitin S.

    2015-01-01

    Purpose: Complete removal of all fragments is the goal of any intervention for urinary stones. This is more important in lower pole stones where gravity and spatial orientation of lower pole infundibulum may hinder spontaneous passage of fragments. Various adjuvant therapies (inversion, diuresis, percussion, oral citrate, etc.) are described to enhance stone-free rate but are not widely accepted. Focused ultrasound-guided relocation of fragments is a recently described technique aimed at improving results of intervention for stone disease. Purpose of this review is to discuss development of this technology and its potential clinical applications. Materials and Methods: Pubmed search was made using key words Focused ultrasound and kidney stone. All English language articles were reviewed by title. Relevant studies describing development and application of focused ultrasound in renal stones were selected for review. Results: Focused ultrasound has proven its efficacy in successfully relocating up to 8 mm stone fragments in vitro and in pigs. Relocation is independent of stone composition. The latest model allows imaging and therapy with a single handheld probe facilitating its use by single operator. The acoustic energy delivered by the new prototype is even less than that used for extracorporeal shock wave lithotripsy. Therapeutic exposure has not caused thermal injury in pig kidneys. Conclusion: Focused ultrasound-guided relocation of stones is feasible. Though it is safe in application in pigs, technology is awaiting approval for clinical testing in human beings. This technology has many potential clinical applications in the management of stone disease. PMID:25624572

  19. Management of stone disease in infants.

    PubMed

    Azili, Mujdem Nur; Ozturk, Fatma; Inozu, Mihriban; ayci, Fatma ?emsa; Acar, Banu; Ozmert, Sengul; Tiryaki, Tugrul

    2015-11-01

    Evaluating and treating renal stone disease in infants are technically challenging. In this study, we evaluated the surgical treatment of renal stones in children under 1 year of age. We retrospectively reviewed the records of patients under 1 year old who were treated with ESWL, endourological or open surgical procedures for renal stone disease between January, 2009 and December, 2012. The patients' age, gender, stone size, stone location and number, complications, stone-free status, and postoperative complications were recorded. 19 of 121 infants with a mean age of 10.2 3.07 months were treated with surgical procedures. Six (75%) of eight cystinuria patients required a surgical intervention. Retrograde endoscopic management was performed in thirteen patients (63.4%) as an initial surgical approach. There were three major (15.7%) complications. The rate of open surgical procedures was 31.6% (6 of 19 infants). The cutoff value of stone size for open surgery was 10 mm. There was a significant relationship between the conversion to open procedures and stone size, stone location, and symptom presentation especially the presence of obstruction (p < 0.05). After repeated treatments, the stone clearance rate of RIRS reached 84.6%. Retrograde intrarenal surgery is an effective and safe treatment method for renal stones in infants and can be used as a first-line therapy in most patients under 1 year old. This is especially important if an associated ureteral stone or lower pole stone that requires treatment is present and for patients with cystinuria, which does not respond favorably to ESWL. PMID:26036325

  20. An Oxalyl-CoA Dependent Pathway of Oxalate Catabolism Plays a Role in Regulating Calcium Oxalate Crystal Accumulation and Defending against Oxalate-Secreting Phytopathogens in Medicago truncatula

    PubMed Central

    Foster, Justin; Luo, Bin; Nakata, Paul A.

    2016-01-01

    Considering the widespread occurrence of oxalate in nature and its broad impact on a host of organisms, it is surprising that so little is known about the turnover of this important acid. In plants, oxalate oxidase is the most well studied enzyme capable of degrading oxalate, but not all plants possess this activity. Recently, an Acyl Activating Enzyme 3 (AAE3), encoding an oxalyl-CoA synthetase, was identified in Arabidopsis. AAE3 has been proposed to catalyze the first step in an alternative pathway of oxalate degradation. Whether this enzyme and proposed pathway is important to other plants is unknown. Here, we identify the Medicago truncatula AAE3 (MtAAE3) and show that it encodes an oxalyl-CoA synthetase activity exhibiting high activity against oxalate with a Km = 81 ± 9 μM and Vmax = 19 ± 0.9 μmoles min-1mg protein-1. GFP-MtAAE3 localization suggested that this enzyme functions within the cytosol of the cell. Mtaae3 knock-down line showed a reduction in its ability to degrade oxalate into CO2. This reduction in the capacity to degrade oxalate resulted in the accumulation of druse crystals of calcium oxalate in the Mtaae3 knock-down line and an increased susceptibility to oxalate-secreting phytopathogens such as Sclerotinia sclerotiorum. Taken together, these results suggest that AAE3 dependent turnover of oxalate is important to different plants and functions in the regulation of tissue calcium oxalate crystal accumulation and in defense against oxalate-secreting phytopathogens. PMID:26900946

  1. An Oxalyl-CoA Dependent Pathway of Oxalate Catabolism Plays a Role in Regulating Calcium Oxalate Crystal Accumulation and Defending against Oxalate-Secreting Phytopathogens in Medicago truncatula.

    PubMed

    Foster, Justin; Luo, Bin; Nakata, Paul A

    2016-01-01

    Considering the widespread occurrence of oxalate in nature and its broad impact on a host of organisms, it is surprising that so little is known about the turnover of this important acid. In plants, oxalate oxidase is the most well studied enzyme capable of degrading oxalate, but not all plants possess this activity. Recently, an Acyl Activating Enzyme 3 (AAE3), encoding an oxalyl-CoA synthetase, was identified in Arabidopsis. AAE3 has been proposed to catalyze the first step in an alternative pathway of oxalate degradation. Whether this enzyme and proposed pathway is important to other plants is unknown. Here, we identify the Medicago truncatula AAE3 (MtAAE3) and show that it encodes an oxalyl-CoA synthetase activity exhibiting high activity against oxalate with a Km = 81 9 ?M and Vmax = 19 0.9 ?moles min-1mg protein-1. GFP-MtAAE3 localization suggested that this enzyme functions within the cytosol of the cell. Mtaae3 knock-down line showed a reduction in its ability to degrade oxalate into CO2. This reduction in the capacity to degrade oxalate resulted in the accumulation of druse crystals of calcium oxalate in the Mtaae3 knock-down line and an increased susceptibility to oxalate-secreting phytopathogens such as Sclerotinia sclerotiorum. Taken together, these results suggest that AAE3 dependent turnover of oxalate is important to different plants and functions in the regulation of tissue calcium oxalate crystal accumulation and in defense against oxalate-secreting phytopathogens. PMID:26900946

  2. Nephrocalcinosis in animal models with and without stones

    PubMed Central

    2010-01-01

    Nephrocalcinosis is the deposition of calcium salts in renal parenchyma and can be intratubular or interstitial. Animal model studies indicate that intratubular nephrocalcinosis is a result of increased urinary supersaturation. Urinary supersaturation with respect to calcium oxalate (CaOx) and calcium phosphate (CaP) are generally achieved at different locations in the renal tubules. As a result experimental induction of hyperoxaluria in animals with CaP deposits does not lead to growth of CaOx over CaP. Interstitial nephrocalcinosis has been seen in mice with lack of crystallization modulators Tamm–Horsfall protein and osteopontin. Sodium phosphate co-transporter or sodiumhydrogen exchanger regulator factor-1 null mice also produced interstitial nephrocalcinosis. Crystals plug the tubules by aggregating and attaching to the luminal cell surface. Structural features of the renal tubules also play a role in crystal retention. The crystals plugging the terminal collecting ducts when exposed to the metastable pelvic urine may promote the formation of stone. PMID:20658131

  3. Arthritis associated with calcium oxalate crystals in an anephric patient treated with peritoneal dialysis

    SciTech Connect

    Rosenthal, A.; Ryan, L.M.; McCarty, D.J.

    1988-09-02

    The authors report a case of calcium oxalate arthropathy in a woman undergoing intermittent peritoneal dialysis who was not receiving pharmacologic doses of ascorbic acid. She developed acute arthritis, with calcium oxalate crystals in Heberden's and Bouchard's nodes, a phenomenon previously described in gout. Intermittent peritoneal dialysis may be less efficient than hemodialysis in clearing oxalate, and physicians should now consider calcium oxalate-associated arthritis in patients undergoing peritoneal dialysis who are not receiving large doses of ascorbic acid.

  4. The abiotic degradation of soil organic matter to oxalic acid

    NASA Astrophysics Data System (ADS)

    Studenroth, Sabine; Huber, Stefan; Schler, H. F.

    2010-05-01

    The abiotic degradation of soil organic matter to volatile organic compounds was studied intensely over the last years (Keppler et al., 2000; Huber et al., 2009). It was shown that soil organic matter is oxidised due to the presence of iron (III), hydrogen peroxide and chloride and thereby produces diverse alkyl halides, which are emitted into the atmosphere. The formation of polar halogenated compounds like chlorinated acetic acids which are relevant toxic environmental substances was also found in soils and sediments (Kilian et al., 2002). The investigation of the formation of other polar halogenated and non-halogenated compounds like diverse mono- and dicarboxylic acids is going to attain more and more importance. Due to its high acidity oxalic acid might have impacts on the environment e.g., nutrient leaching, plant diseases and negative influence on microbial growth. In this study, the abiotic formation of oxalic acid in soil is examined. For a better understanding of natural degradation processes mechanistic studies were conducted using the model compound catechol as representative for structural elements of the humic substances and its reaction with iron (III) and hydrogen peroxide. Iron is one of the most abundant elements on earth and hydrogen peroxide is produced by bacteria or through incomplete reduction of oxygen. To find suitable parameters for an optimal reaction and a qualitative and quantitative analysis method the following reaction parameters are varied: concentration of iron (III) and hydrogen peroxide, time dependence, pH-value and influence of chloride. Analysis of oxalic acid was performed employing an ion chromatograph equipped with a conductivity detector. The time dependent reaction shows a relatively fast formation of oxalic acid, the optimum yield is achieved after 60 minutes. Compared to the concentration of catechol an excess of hydrogen peroxide as well as a low concentration of iron (III) are required. In absence of chloride the degradation of catechol to oxalic acid delivers a maximum yield of approximately 60 %, whereas the presence of chloride reduces the formation of oxalic acid to 30 %. Chloride possibly induces further competing reactions of catechol leading to a lower concentration of oxalic acid. Freeze-dried soil samples have been tested for production of oxalic acid, where the rate of organic matter seems to play an important role for the formation. By adding iron (III) and/or hydrogen peroxide oxalic acid yields increase, which demonstrates the reaction of soil organic matter with iron (III) and hydrogen peroxide as expected. Thus the natural abiotic formation of oxalic acid is confirmed. The results of the soil measurements are similar to those obtained with catechol. Therefore, the newly gained insights with model compounds appear to be applicable to soil conditions and these findings increase our understanding of the degradation pathways of soil organic matter. Furthermore an overview of the rates of oxalic acid formation of a variety of soil samples is shown and discussed in the light of different soil parameter.

  5. Long-term follow-up of stone formers treated with a low dose of sodium potassium citrate.

    PubMed

    Jendle-Bengten, C; Tiselius, H G

    2000-02-01

    We evaluated the clinical efficacy of long-term preventive treatment with a single evening dose of alkaline citrate. Information was collected from the files of 52 recurrent stone formers prescribed a daily intake of 3.75-5 g of sodium potassium citrate (SPC; 14-18 mmol of citrate). The annual and cumulative rates of stone formation and the rate of recurrence were compared before and during the treatment. A comparison was also made between the patients with (Group R) and without (Group NR) recurrent stone formation during treatment in terms of urine composition and previous history of the disease. For all patients who started the treatment, the number of stones was smaller during treatment (period tT) than during a period of the same length immediately before treatment (period tB), but greater than the number formed during a corresponding period immediately after the diagnosis (period tA). Via questionnaire we found low treatment compliance, with only 62% of the patients reporting consistent taking of their medication (Group T). The patients in Group T had a smaller cumulated number of stones during period tT than that during periods tA and tB, but the Kaplan-Meier curve of the fraction of patients remaining stone-free during treatment was almost identical to that recorded in 446 recurrent stone formers without medical treatment. No significant differences were recorded in terms of relevant pretreatment urinary risk factors between Groups T(R) and T(NR), but numerically higher values of calcium oxalate (CaOx) supersaturation and calcium/citrate quotients were observed in Group T(R). When 9 patients with a daily intake of SPC and a citrate excretion below 2.5 mmol/day were compared with 16 hypocitraturic patients only given drinking advice, the cumulated percentages of patients without recurrent stone formation in the 2 groups after 3 years were 44% and 48%, respectively. Although the number of patients in this study was small, our results indicate poor long-term protection from recurrent calcium stone formation when a single evening dose of only 3.75-5 g of SPC was taken. The rate of stone formation was apparently slightly reduced, but the fraction of patients free of recurrence was no different from that in patients without medical treatment. PMID:10757268

  6. Evaluation of Oxalate Concentration in the U.S. Spinach Germplasm Collection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to its high nutrient content, spinach (Spinacia oleracea L.) is also known to have greater amount of oxalic acid than most crops. Oxalic acid may form crystals with minerals to reduce the bioavailability and absorption of calcium and iron in diets, and calcium oxalate may deposit in the...

  7. PREPARATION OF OXALATES OF METALS OF ATOMIC NUMBER GREATER THAN 88

    DOEpatents

    Duffield, R.B.

    1959-02-01

    A method is presented for the preparation of oxalates of metals of atomic number greater than 88. A solid peroxide of the heavy metal is contacted with an aqueous oxalic acid solution ai a temperature of about 50 C for a period of time sufficient to form the insoluble metal oxalate which is subsequentiy recovered as a pures crystalline compound.

  8. Genomic evaluation of oxalate-degrading transgenic soybean in response to Sclerotinia sclerotiorum infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxalate oxidases catalyze the degradation of oxalic acid (OA). Highly resistant transgenic soybean carrying an oxalate oxidase (OxO) gene and its susceptible parent soybean line, AC Colibri, were tested for genome-wide gene expression in response to the necrotrophic, OA producing pathogen Sclerotini...

  9. ISOLATED MEDICAGO TRUNCATULA MUTANTS WITH INCREASED CALCIUM OXALATE CRYSTAL ACCUMULATION HAVE DECREASED ASCORBIC ACID LEVELS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mechanisms controlling oxalate biosynthesis and calcium oxalate formation in plants remains largely unknown. As an initial step toward gaining insight into these regulatory mechanisms we initiated a mutant screen to identify plants that over-accumulate crystals of calcium oxalate. Four new mut...

  10. Metal Accumulation without Enhanced Oxalate Secretion in Wood Degraded by Brown Rot Fungi

    PubMed Central

    Schilling, Jonathan S.; Jellison, Jody

    2006-01-01

    Brown rot fungi were incubated in agar and agar-wood microcosms containing metallic or hydroxide forms of Al, Cu, and Fe. Metal dissolution was associated with elevated oxalate concentrations in agar, but metals translocated into wood did not affect oxalate accumulation, crystal production, or decay rate, demonstrating a substrate-dependent oxalate dynamic. PMID:16885326

  11. Investigations of stone consolidants by neutron imaging

    NASA Astrophysics Data System (ADS)

    Hameed, F.; Schillinger, B.; Rohatsch, A.; Zawisky, M.; Rauch, H.

    2009-06-01

    The chemical preservation and structural reintegration of natural stones applied in historical buildings is carried out by the use of different stone strengtheners. As these agents contain hydrogen, they offer good properties for neutron imaging. The main interest in the restoration process is the development of a suitable stone consolidant. In cooperation with the St. Stephans Cathedral and the geologists at Vienna University of Technology, we are investigating the penetration depth and distribution of different stone consolidants. These studies are being carried out with different stone samples, mostly porous natural building stones, limestones and sandstones. The two strengtheners used in this study are ethyl silicate ester (Wacker OH100) and dissolved polymethylmetacrylate (PMMA, Paraloid B72). Neutron radiography and neutron tomography can be used successfully to visualize the distribution of consolidants both in two and three dimensions.

  12. Clonorcis sinensis eggs are associated with calcium carbonate gallbladder stones.

    PubMed

    Qiao, Tie; Ma, Rui-hong; Luo, Zhen-liang; Yang, Liu-qing; Luo, Xiao-bing; Zheng, Pei-ming

    2014-10-01

    Calcium carbonate gallbladder stones were easily neglected because they were previously reported as a rare stone type in adults. The aim of this study was to investigate the relationship between calcium carbonate stones and Clonorchis sinensis infection. A total of 598 gallbladder stones were studied. The stone types were identified by FTIR spectroscopy. The C. sinensis eggs and DNA were detected by microscopic examination and real-time fluorescent PCR respectively. And then, some egg-positive stones were randomly selected for further SEM examination. Corresponding clinical characteristics of patients with different types of stones were also statistically analyzed. The detection rate of C. sinensis eggs in calcium carbonate stone, pigment stone, mixed stone and cholesterol stone types, as well as other stone types was 60%, 44%, 36%, 6% and 30%, respectively, which was highest in calcium carbonate stone yet lowest in cholesterol stone. A total of 182 stones were egg-positive, 67 (37%) of which were calcium carbonate stones. The C. sinensis eggs were found adherent to calcium carbonate crystals by both light microscopy and scanning electron microscopy. Patients with calcium carbonate stones were mainly male between the ages of 30 and 60, the CO2 combining power of patients with calcium carbonate stones were higher than those with cholesterol stones. Calcium carbonate gallbladder stones are not rare, the formation of which may be associated with C. sinensis infection. PMID:24945791

  13. 6. GRIST MILL STONES IN CENTER (VERTICAL STAND WITH HANDLE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. GRIST MILL STONES IN CENTER (VERTICAL STAND WITH HANDLE TO LEFT OF STONES ADJUSTS SPACE BETWEEN STONES, THUS CONTROLING FINENESS OF FLOUR. STONE CRANE AT RIGHT USED TO LIFT STONES FOR DRESSING). OTHER EQUIPMENT NOT IDENTIFIED. NOTE STAIRS IN LEFT REAR. - Hildebrand's Mill, Flint, Delaware County, OK

  14. CALCIUM CHANNELS INVOLVED IN CALCIUM OXALATE CRYSTAL FORMATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pistia stratiotes L. produces calcium (Ca) oxalate crystals in specialized cells called crystal idioblasts. Druse crystal idioblasts are produced in the adaxial mesophyll and raphide idioblasts are produced in the abaxial aerenchyma of this aquatic plant. Leaves formed on plants grown on 0 Ca medi...

  15. CALCIUM OXALATE CRYSTAL MORPHOLOGY MUTANTS FROM MEDICAGO TRUNCATULA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants accumulate crystals of calcium oxalate in a variety of shapes and sizes. Each plant forms a crystal or set of crystals with a specific morphology. The mechanism(s) through which a plant defines the morphology of its crystals remains unknown. To gain insight into the mechanisms regulating c...

  16. Production of battery grade materials via an oxalate method

    SciTech Connect

    Belharouak, Ilias; Amine, Khalil

    2014-04-29

    An active electrode material for electrochemical devices such as lithium ion batteries includes a lithium transition metal oxide which is free of sodium and sulfur contaminants. The lithium transition metal oxide is prepared by calcining a mixture of a lithium precursor and a transition metal oxalate. Electrochemical devices use such active electrodes.

  17. Oxalate Mass Balance During Chemical Cleaning in Tank 5F

    SciTech Connect

    Poirier, M.; Fink, S.

    2011-07-08

    The Savannah River Site (SRS) is preparing Tank 5F for closure. The first step in preparing the tank for closure is mechanical sludge removal. Following mechanical sludge removal, SRS performed chemical cleaning with oxalic acid to remove the sludge heel. Personnel are currently assessing the effectiveness of the chemical cleaning to determine whether the tank is ready for closure. SRS personnel collected liquid samples during chemical cleaning and submitted them to Savannah River National Laboratory (SRNL) for analysis. Following chemical cleaning, they collected a solid sample (also known as 'process sample') and submitted it to SRNL for analysis. The authors analyzed these samples to assess the effectiveness of the chemical cleaning process. Analysis of the anions showed the measured oxalate removed from Tank 5F to be approximately 50% of the amount added in the oxalic acid. To close the oxalate mass balance, the author collected solid samples, leached them with nitric acid, and measured the concentration of cations and anions in the leachate.

  18. 21 CFR 862.1542 - Oxalate test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Oxalate test system. 862.1542 Section 862.1542 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  19. Isolation and characterization of some new oxalate-decomposing bacteria.

    PubMed

    Chandra, T S; Shethna, Y I

    1975-01-01

    Forty-one cultures degrading and assimilating oxalate were isolated from chicken dung. Characterizarion indicated six different types. One of these belonged to thhe genus Alcaligenes hitherto never reported to degrade oxalte. Three groups of Pseudomonas strains differed physiologically from strains already known. PMID:1080384

  20. Interconversions between oxalic acid monoamide rotamers: Photochemical process versus tunneling

    NASA Astrophysics Data System (ADS)

    Maier, Gnther; Endres, Jrg; Reisenauer, Hans Peter

    2012-10-01

    UV irradiation converts matrix isolated (E,E)-oxalic acid monoamide (4) to its energetically less favorable (E,Z)-rotamer 5. The back-reaction 5 ? 4 seems to be governed by [H]tunneling. Matrix IR spectroscopy in combination with density functional computations is the method of choice to identify the bridged and unbridged rotamers 4 and 5.

  1. GADOLINIUM OXALATE SOLUBILITY MEASUREMENTS IN NITRIC ACID SOLUTIONS

    SciTech Connect

    Pierce, R.

    2012-02-22

    HB-Line will begin processing Pu solutions during FY2012 that will involve the recovery of Pu using oxalate precipitation and filtration. After the precipitation and filtration processes, the filtrate solution will be transferred from HB-Line to H-Canyon. The presence of excess oxalate and unfiltered Pu oxalate solids in these solutions create a criticality safety issue if they are sent to H-Canyon without controls in H-Canyon. One approach involves H-Canyon receiving the filtrate solution into a tank that is poisoned with soluble gadolinium (Gd). Decomposition of the oxalate will occur within a subsequent H-Canyon vessel. The receipt of excess oxalate into the H-Canyon receipt tanks has the potential to precipitate a portion of the Gd poison in the receipt tanks. Because the amount of Gd in solution determines the maximum amount of Pu solids that H-Canyon can receive, H-Canyon Engineering requested that SRNL determine the solubility of Gd in aqueous solutions of 4-10 M nitric acid (HNO{sub 3}), 4-12 g/L Gd, and 0.15-0.25 M oxalic acid (H{sub 2}C{sub 2}O{sub 4}) at 25 C. The target soluble Gd concentration is 6 g/L. The data indicate that the target can be achieved above 6 M HNO{sub 3} and below 0.25 M H{sub 2}C{sub 2}O{sub 4}. For 6 M HNO{sub 3}, 10.5 g/L and 7 g/L Gd are soluble in 0.15 M and 0.25 M H{sub 2}C{sub 2}O{sub 4}, respectively. In 4 M HNO{sub 3}, the Gd solubility drops significantly to 2 g/L and 0.25 g/L in 0.15 M and 0.25 M H{sub 2}C{sub 2}O{sub 4}, respectively. The solubility of Gd at 8-10 M HNO{sub 3} exceeds the solubility at 6 M HNO{sub 3}. The data for 4 M HNO{sub 3} showed good agreement with data in the literature. To achieve a target of 6 g/L soluble Gd in solution in the presence of 0.15-0.25 M oxalate, the HNO{sub 3} concentration must be maintained at or above 6 M HNO{sub 3}.

  2. Caoxite-hydroxyapatite composition as consolidating material for the chalk stone from Basarabi-Murfatlar churches ensemble

    NASA Astrophysics Data System (ADS)

    Ion, Rodica-Mariana; Turcanu-Caruţiu, Daniela; Fierăscu, Radu-Claudiu; Fierăscu, Irina; Bunghez, Ioana-Raluca; Ion, Mihaela-Lucia; Teodorescu, Sofia; Vasilievici, Gabriel; Rădiţoiu, Valentin

    2015-12-01

    The development of new composition for surface conservation of some architectural monuments represents now an important research topic. The Basarabi-Murfatlar Ensemble, recognized as the first religious monument from mediaeval Dobrogea (Romania) (from 9th to 11th century), is one of the most impressive archaeological sites of Europe. This ensemble is built from amorphous calcium carbonate, very sensitive to humidity, frost, salts, etc. The aim of this paper is to test on chalk stone samples a new consolidant - hydroxyapatite (HAp) mixed with calcium oxalate trihydrate (caoxite) (COT). Some specific techniques for evaluation its impact on chalk stone surface are used, as follows: petrographical and physical-chemical techniques: SEM, OM, ICP-AES, TGA, FTIR and Raman spectroscopy, chromatic parameters changes, the accelerated weathering tests: heating, freeze-thaw, and their effects on porosity and capillary water uptake by the chalk surface. All these have been evaluated before and after treatment with COT-HAp, putting into evidence the effect of the new composition on the chalk stone surface. HAp induces COT stabilization, and their joint composition can bind weathered stone blocks providing a substantial reinforcement of chalk surface.

  3. Can the manipulation of urinary pH by beverages assist with the prevention of stone recurrence?

    PubMed

    Siener, Roswitha

    2016-02-01

    The formation of various types of stones in the urinary tract is strongly influenced by urinary pH. An acidic urinary pH promotes the crystallization of uric acid and cystine, respectively. Moreover, changes in systemic acid-base homeostasis alter urinary excretion of citrate, an important inhibitor of calcium oxalate stone formation. The effect of beverages on urinary pH and citrate excretion is mainly determined by the presence of bicarbonate and citrate. The bicarbonate content of mineral water can replace alkalization therapy with potassium citrate and contribute to urine inhibitory power by increasing urinary pH and citrate excretion. Citrus juices are rich sources of citrate. Oral citrate is absorbed in the intestine and nearly completely metabolized to bicarbonate, providing an alkali load, which in turn increases urinary pH and citrate excretion. However, data from observational and interventional studies on the effect of different types of citrus juices on the risk of urinary stone formation are conflicting. In conclusion, favourable changes in urinary pH and citrate excretion can be attained by various beverages. However, the long-term efficacy of certain beverages for the recurrence prevention of different types of stones has yet to be determined. PMID:26614113

  4. Global stone heritage: larvikite, Norway

    NASA Astrophysics Data System (ADS)

    Heldal, Tom; Dahl, Rolv

    2013-04-01

    Larvikite has for more than hundred years been appreciated as one of the world's most attractive dimension-stones, and at present time its production and use is more extensive than ever. The main reason for the continuous success of the larvikite on the world market is the blue iridescence displayed on polished surfaces, which is caused by optical interference in microscopic lamellae within the ternary feldspars. The larvikite complex consists of different intrusions defining several ring-shaped structures, emplaced during a period of approximately five million years. Following this pattern, several commercial subtypes of larvikite, characterised by their colour and iridescence, have been identified. The name "larvikite" was first applied by Waldemar Brøgger, in his descriptions of the monzonitic rocks within the southern part of the Carboniferous-Permian Oslo Igneous Province. The name has its origin in the small coastal town of Larvik, situated almost right in the centre of the main plutonic complex of larvikite. From a geologist's point of view, the larvikites are important for understanding the igneous mechanisms behind the formation of the Oslo rift, representing a series of semi-circular intrusions, varying from quartz-bearing monzonites in the east (earliest phases) towards nepheline-bearing monzonites and nepheline syenite in the west (latest phases). However, most other people see larvikite as a particularly beautiful rock. Production started already in the 1880s, and at present time the export value of rough blocks of dimension-stone from the Larvik Region is close to 100 million euro, distributed on approximately 20 individual quarries. Different types of larvikite have different market value, and the customers can choose between a range of types and qualities under trade names such as "Blue Pearl", "Emerald Pearl" and "Marina Pearl". Globally, larvikite has put a significant mark on architecture around the world, and should be included in the global stone heritage.

  5. Biogeochemistry of oxalate in the antarctic cryptoendolithic lichen-dominated community.

    PubMed

    Johnston, C G; Vestal, J R

    1993-05-01

    Cryptoendolithic (hidden in rock) lichen-dominated microbial communities from the Ross Desert of Antarctica were shown to produce oxalate (oxalic acid). Oxalate increased mineral dissolution, which provides nutrients, creates characteristic weathering patterns, and may ultimately influence the biological residence time of the community. Oxalate was the only organic acid detectable by HPLC, and its presence was verified by GC/MS. Community photosynthetic metabolism was involved in oxalate production since rates of (14)C-oxalate production from (14)C02 were higher in light than in dark incubations. Flaking of the sandstone at the level of the lichen-dominated zone a few millimeters beneath the rock surface can be explained by dissolution of the sandstone cement, which was enhanced by Si, Fe, and Al oxalate complex formation. Added oxalate was observed to increase the solubility of Si, Fe, Al, P, and K. Oxalate's ability to form soluble trivalent metal-oxalate complexes correlated with the observed order of metal oxide depletion from the lichen-dominated zone (Mn > Fe > Al). Thermodynamic calculations predict that Fe oxalate complex formation mobilizes amorphous Fe oxides (ferrihydrite) in the lichen-dominated zone, and where oxalate is depleted, ferrihydrite should precipitate. Hematite, a more crystalline Fe oxide, should remain solid at in situ oxalate concentrations. Oxalate was not a carbon source for the indigenous heterotrophs, but the microbiota were involved in oxalate mineralization to CO2, since oxalate mineralization was reduced in poisoned incubations. Photooxidation of oxalate to C02 coupled with photoreduction of Fe(Ill) may be responsible for oxalate removal in situ, since rates of (14)C-oxalate mineralization in dark incubations were at least 50% lower than those in the light. Removal of oxalate from Si, Fe, and Al complexes should allow free dissolved Si, Fe, and Al to precipitate as amorphous silicates and metal oxides. This may explain increased siliceous crust (rock varnish or desert varnish) formation near the surface of colonized rocks were light intensity is greatest. PMID:24189925

  6. Ab initio structural and vibrational investigation of sulfuric acid monohydrate.

    PubMed

    Partanen, Lauri; Hänninen, Vesa; Halonen, Lauri

    2012-03-22

    We employ ab initio methods to find stable geometries and to calculate potential energy surfaces and vibrational wavenumbers for sulfuric acid monohydrate. Geometry optimizations are carried out with the explicitly correlated coupled-cluster approach that includes single, double, and perturbative triple excitations (CCSD(T)-F12a) with a valence double-ζ basis set (VDZ-F12). Four different stable geometries are found, and the two lowest are within 0.41 kJ mol(-1) (or 34 cm(-1)) of each other. Vibrational harmonic wavenumbers are calculated at both the density-fitted local spin component scaled second-order Møller-Plesset perturbation theory (DF-SCS-LMP2) with the aug-cc-pV(T+d)Z basis set and the CCSD-F12/VDZ-F12 level. Water O-H stretching vibrations and two highly anharmonic large-amplitude motions connecting the three lowest potential energy minima are considered by limiting the dimensionality of the corresponding potential energy surfaces to small two- or three-dimensional subspaces that contain only strongly coupled vibrational degrees of freedom. In these anharmonic domains, the vibrational problem is solved variationally using potential energy surfaces calculated at the CCSD(T)-F12a/VDZ-F12 level. PMID:22260481

  7. Why sildenafil and sildenafil citrate monohydrate crystals are not stable?

    PubMed Central

    Sawatdee, Somchai; Pakawatchai, Chaveng; Nitichai, Kwanjai; Srichana, Teerapol; Phetmung, Hirihattaya

    2015-01-01

    Sildenafil citrate was crystallized by various techniques aiming to determine the behavior and factors affecting the crystal growth. There are only 2 types of sildenafil obtaining from crystallization: sildenafil (1) and sildenafil citrate monohydrate (2). The used techniques were (i) crystallization from saturated solutions, (ii) addition of an antisolvent, (iii) reflux and (iv) slow solvent evaporation method. By pursuing these various methods, our work pointed that the best formation of crystal (1) was obtained from technique no. (i). Surprisingly, the obtained crystals (1) were perfected if the process was an acidic pH at a cold temperature then perfect crystals occurred within a day. Crystals of compound (2) grew easily using technique no. (ii) which are various polar solvents over a wide range of pH and temperature preparation processes. The infrared spectroscopy and nuclear magnetic resonance spectra fit well with these two X-ray crystal structures. The crystal structures of sildenafil free base and salt forms were different from their different growing conditions leading to stability difference. PMID:26594116

  8. L-Tryptophan L-tryptophanium bromide: Anhydrous and monohydrate

    NASA Astrophysics Data System (ADS)

    Ghazaryan, V. V.; Giester, G.; Fleck, M.; Petrosyan, A. M.

    2015-12-01

    L-Tryptophan L-tryptophanium bromide (I) and L-tryptophan L-tryptophanium bromide monohydrate (II) are new salts with (A⋯A+) type dimeric cation. The salt (I) crystallizes in the monoclinic system (space group P21, Z = 2) and is isostructural with respective chloride (V.V. Ghazaryan et al., Spectrochim. Acta A 136(2015) 743-750), while the salt (II) was obtained previously (T. Takigawa et al., Bull. Chem. Soc. Jap. 39(1966) 2369-2378) and described as hemyhydrate without structure determination. The salt (II) crystallizes in orthorhombic system (space group P212121, Z = 4). The dimeric cations in (I) and (II) are formed by O-H⋯O hydrogen bonds with the O⋯O distances equal to 2.538(3) Å and 2.481(3) Å respectively. The infrared and Raman spectra of the crystals are studied and compared with the spectra of L-tryptophan L-tryptophanium chloride and L-tryptophanium bromide.

  9. Hypoglycemic effects of vanadium on alloxan monohydrate induced diabetic dogs

    PubMed Central

    Kim, Joo-Min; Chung, Jin-Young; Lee, Sook-Yeon; Choi, Eun-Wha; Kim, Min-Kyu; Hwang, Cheol-Yong

    2006-01-01

    The hypoglycemic effects after oral administration of vanadium have been studied previously in many species such as rats, mice and even humans. However, there has been no prior report on the glucose lowering effect of vanadium on diabetic dogs. Therefore, the purpose of this study was to evaluate the hypoglycemic effects of oral vanadium on diabetic dogs. Diabetes mellitus in the dogs studied was induced by alloxan monohydrate intravenous injection. The dogs were divided into two groups, one was the diabetic control (DC) group (n = 4) and the other was the vanadium treated (DV) group (n = 6). Fresh water was supplied to the dogs in the DC group, but sodium metavanadate solution (0.1~0.2 mg/ml) was given to the dogs in DV group from one week after the alloxan injection. The fasting glucose levels, fructosamine and serum chemistry profiles were compared between the two groups weekly for three weeks. The fasting blood glucose levels in DV group were significantly lower than those in the DC group (p < 0.01). Fructosamine levels in the DV group were also lower than those in the DC group (p < 0.05). The serum chemistry profiles were not significantly different in comparisons between the two groups. However, the cholesterol levels were significantly lower in the DV group compared to the DC group (p < 0.05). Our findings showed that oral vanadium administration had a hypoglycemic effect on chemically induced diabetic dogs. PMID:17106233

  10. Why sildenafil and sildenafil citrate monohydrate crystals are not stable?

    PubMed

    Sawatdee, Somchai; Pakawatchai, Chaveng; Nitichai, Kwanjai; Srichana, Teerapol; Phetmung, Hirihattaya

    2015-10-01

    Sildenafil citrate was crystallized by various techniques aiming to determine the behavior and factors affecting the crystal growth. There are only 2 types of sildenafil obtaining from crystallization: sildenafil (1) and sildenafil citrate monohydrate (2). The used techniques were (i) crystallization from saturated solutions, (ii) addition of an antisolvent, (iii) reflux and (iv) slow solvent evaporation method. By pursuing these various methods, our work pointed that the best formation of crystal (1) was obtained from technique no. (i). Surprisingly, the obtained crystals (1) were perfected if the process was an acidic pH at a cold temperature then perfect crystals occurred within a day. Crystals of compound (2) grew easily using technique no. (ii) which are various polar solvents over a wide range of pH and temperature preparation processes. The infrared spectroscopy and nuclear magnetic resonance spectra fit well with these two X-ray crystal structures. The crystal structures of sildenafil free base and salt forms were different from their different growing conditions leading to stability difference. PMID:26594116

  11. Energy-based analysis of milling alpha-lactose monohydrate.

    PubMed

    Chen, Y; Ding, Y; Papadopoulos, D G; Ghadiri, M

    2004-04-01

    Some observations on the milling of alpha-lactose monohydrate with a Retsch single-ball mill are reported. The effects of mill loading and frequency of the mill motion were investigated. At a given frequency, a lower mill loading showed a higher milling efficiency. For a given mill loading, size reduction rate increased exponentially with frequency. The milling behavior was analyzed with three energy-based models; namely, Rittinger's, Kick's, and Bond's models. The results suggest that Rittinger's model best describes the milling behavior for low mill loadings at high frequencies, whereas the data for high loading milling at low frequencies fit Kick's model better. The results also indicate that attrition and/or chipping is the dominant mechanism for milling at low frequencies with high loadings because of the shear action of the milling ball rolling on the powder bed. Also, as a result of impact of the milling ball on the two ends of the milling jar, fragmentation is responsible for size reduction at high frequencies with low loadings. PMID:14999726

  12. Characterization of a new anhydrous form of Rotundine and its monohydrate

    NASA Astrophysics Data System (ADS)

    Yang, Shiying; Du, Guanhua; Lu, Yang

    2015-09-01

    Rotundine is a chemical drug developed from Chinese traditional medicines that exhibits pseudopolymorphism. The anhydrous form and monohydrate are isolated and prepared via systemic crystallization screening, and the anhydrous form is reported for the first time. In this article single crystal X-ray diffractometry, powder X-ray diffractometry and FT-IR spectroscopy are used to characterize the Rotundine modifications. The analysis results show that the factors of crystal symmetry, intermolecular arrangements, conformational flexibility, hydrogen bonding interactions, and the incorporation of water finally lead to produce the polymorphic phenomenon. Via the in-vivo bioavailability of two forms, it is found that the new anhydrous form presents absorbable superiority relative to monohydrate, specifically Cmax and AUC of anhydrous form were approximately 1.5 times those of monohydrate. Study on the transformation of two forms show that they can convert to each other in certain conditions at solid state.

  13. The effects of the recommended dose of creatine monohydrate on kidney function.

    PubMed

    Taner, Basturk; Aysim, Ozagari; Abdulkadir, Unsal

    2011-02-01

    We report a case of a heretofore healthy 18-year-old man who presented with a 2-day history of nausea, vomiting and stomach ache while taking creatine monohydrate for bodybuilding purposes. The patient had acute renal failure, and a renal biopsy was performed to determine the cause of increased creatinine and proteinuria. The biopsy showed acute tubular necrosis. In the literature, creatine monohydrate supplementation and acute tubular necrosis coexistence had not been reported previously. Twenty-five days after stopping the creatine supplements, the patient recovered fully. Even recommended doses of creatine monohydrate supplementation may cause kidney damage; therefore, anybody using this supplement should be warned about this possible side effect, and their renal functions should be monitored regularly. PMID:25984094

  14. Changes in stone composition over two decades: evaluation of over 10,000 stone analyses.

    PubMed

    Moses, Rachel; Pais, Vernon M; Ursiny, Michal; Prien, Edwin L; Miller, Nicole; Eisner, Brian H

    2015-04-01

    To examine the changes in stone composition from 1990 to 2010. A retrospective review was performed of all renal and ureteral stones submitted from the state of Massachusetts to a single laboratory (Laboratory for Stone Research, Newton, MA) for the years 1990 and 2010. Stone composition was determined by infrared spectroscopy and/or polarizing microscopy. A total of 11,099 stones were evaluated (56.7% from 1990, 43.3% from 2010). From 1990 to 2010, the percentage of stones from females (i.e., female/male ratio) increased significantly (29.8% in 1990 to 39.1% in 2010, p < 0.001). Among women, from 1990 to 2010, there was a significant increase in stones which were >50% uric acid (7.6-10.2%, p < 0.005) and a significant decrease in struvite stones (7.8-3.0%, p < 0.001). Among women with calcium stones, the % apatite per stone decreased significantly (20.0 vs. 11.7%, p < 0.001). Among men, there were no changes in stones which were majority uric acid (11.7-10.8%, p = 0.2). Among men with calcium stones, the % apatite per stone increased significantly (9.8 vs. 12.5%, p < 0.001). Males also demonstrated a significant increase in both cystine (0.1-0.6%, p < 0.001) and struvite stones (2.8-3.7%, p = 0.02). The epidemiology of stone disease continues to evolve and appears to vary according to gender. While some of these findings may be related to population changes in body mass index and obesity, the etiology of others remains unclear. PMID:25689875

  15. Clofibrate feeding to Sprague-Dawley rats increases endogenous biosynthesis of oxalate and causes hyperoxaluria.

    PubMed

    Sharma, V; Schwille, P O

    1997-02-01

    The effects of clofibrate feeding (5 g/kg diet) on oxalate metabolism were investigated in male and female rats. Following clofibrate feeding, 24-hour urinary excretion of oxalate increased until 4 days and then reached a plateau. Whereas the contribution of dietary oxalate (1.4 g/kg diet, as potassium salt) to urinary oxalate was less than 5% in both control and clofibrate-treated male rats, the contribution of dietary glycolate (1.0 g/kg diet, as sodium salt) to urinary oxalate was six times higher in clofibrate-treated male rats compared with controls, indicating that the clofibrate-induced hyperoxaluria is due to increased endogenous biosynthesis of oxalate. This was supported by the increased lactate dehydrogenase (LDH) activity observed in liver supernatants of clofibrate-treated rats compared with controls, and the increased rate of conversion of glycolate and glyoxylate to oxalate by clofibrate-treated male rat liver supernatants. Female rats had lower excretion of urinary oxalate and lower levels of liver glycolic acid oxidase (GAO) as compared with males. Clofibrate-treated female rat liver supernatants had higher LDH levels and produced more oxalate from glyoxylate. Thus, it can be concluded that the increase in LDH activity may be the cause of the increased endogenous biosynthesis of oxalate leading to increased urinary excretion of oxalate in male and female rats treated with clofibrate. PMID:9030817

  16. Oxalate- and Glyoxylate-Dependent Growth and Acetogenesis by Clostridium thermoaceticum

    PubMed Central

    Daniel, Steven L.; Drake, Harold L.

    1993-01-01

    The acetogenic bacterium Clostridium thermoaceticum ATCC 39073 grew at the expense of the two-carbon substrates oxalate and glyoxylate. Other two-carbon substrates (acetaldehyde, acetate, ethanol, ethylene glycol, glycolaldehyde, glycolate, and glyoxal) were not growth supportive. Growth increased linearly with increasing substrate concentrations up to 45 mM oxalate and glyoxylate, and supplemental CO2 was not required for growth. Oxalate and glyoxylate yielded 4.9 and 9.4 g, respectively, of cell biomass (dry weight) per mol of substrate utilized. Acetate was the major reduced end product recovered from oxalate and glyoxylate cultures. 14C labeling studies showed that oxalate was subject to decarboxylation, and product analysis indicated that oxalate was utilized by the following reaction: 4-OOC-COO- + 5H2O ? CH3COO- + 6HCO3- + OH-. Oxalate- and glyoxylate-dependent growth produced lower acetate concentrations per unit of cell biomass synthesized than did H2-, CO-, methanol-, formate-, O-methyl-, or glucose-dependent growth. Protein profiles of oxalate-grown cells were dissimilar from protein profiles of glyoxylate-, CO-, or formate-grown cells, suggesting induction of new proteins for the utilization of oxalate. C. thermoaceticum DSM 2955 and Clostridium thermoautotrophicum JW 701/3 also grew at the expense of oxalate and glyoxylate. However, oxalate and glyoxylate did not support the growth of C. thermoaceticum OMD (a nonautotrophic strain) or six other species of acetogenic bacteria tested. Images PMID:16349048

  17. Reduction of carbon dioxide to oxalate by a binuclear copper complex.

    PubMed

    Pokharel, Uttam R; Fronczek, Frank R; Maverick, Andrew W

    2014-01-01

    Reduction of carbon dioxide to products such as oxalate (C2O4(2-)) is an active area of research, as the process converts an environmental pollutant into more useful organic compounds. However, carbon dioxide reduction remains a major challenge. Here we demonstrate a three-step reaction sequence in which a copper complex converts carbon dioxide to oxalate under mild conditions. The copper(II) complex is reduced to copper(I) in solution, either electrochemically or using sodium ascorbate. The reduced complex selectively reacts with carbon dioxide from air and fixes it into oxalate, with the oxalate ion bridging between two copper atoms. The bound oxalate ion is released as oxalic acid on treatment with mineral acids, regenerating the original copper(II) complex. This completes the process for conversion of carbon dioxide into oxalate using a binuclear copper complex and a mild reducing agent. PMID:25522935

  18. Acute oxalate nephropathy due to pancreatic atrophy in newly diagnosed pancreatic carcinoma.

    PubMed

    Moinuddin, Irfan; Bala, Asif; Ali, Butool; Khan, Husna; Bracamonte, Erika; Sussman, Amy

    2016-02-01

    Acute oxalate nephropathy can occur due to primary hyperoxaluria and secondary hyperoxaluria. The primary hyperoxalurias are a group of autosomal recessive disorders of endogenous oxalate overproduction. Secondary hyperoxaluria may occur as a result of excess dietary intake, poisoning with oxalate precursors (ethylene glycol), or enteric hyperoxaluria. The differential diagnosis of enteric hyperoxaluria includes inflammatory bowel disease, short bowel syndrome, bariatric surgery (with jejunoileal bypass or Roux-en-Y gastric bypass), celiac disease, partial colectomy, and chronic pancreatitis. The common etiology in all these processes is fat malabsorption, steatorrhea, saponification of calcium, and absorption of free oxalate. Hyperoxaluria causes increased urinary oxalate excretion, urolithiasis (promoted by hypovolemia, decreased urinary pH caused by metabolic acidosis, and decreased citrate and magnesium concentrations in urine), tubulointerstitial oxalate deposits, and tubulointerstitial nephritis. We report a rare case of acute oxalate nephropathy due to pancreatic atrophy and exocrine insufficiency caused by newly diagnosed pancreatic cancer. PMID:26614399

  19. Sildenafil citrate monohydrate-cyclodextrin nanosuspension complexes for use in metered-dose inhalers.

    PubMed

    Sawatdee, Somchai; Phetmung, Hirihattaya; Srichana, Teerapol

    2013-10-15

    Sildenafil is a selective phosphodiesterase-5 inhibitor used for the treatment of erectile dysfunction and pulmonary hypertension. Sildenafil citrate monohydrate was complexed with α-, hydroxypropyl-β- and γ-cyclodextrin (α-CD, HP-β-CD and γ-CD, respectively) to enhance its water solubility. The complexes of sildenafil citrate monohydrate with all types of CDs were characterized by phase solubility diagrams, (1)H and (13)C NMR, and dielectric constants. Sildenafil citrate monohydrate complexed with CDs was developed as