Oxalate and Sucralose Absorption in Idiopathic Calcium Oxalate Stone Formers

PubMed Central

Knight, John; Jiang, Juquan; Wood, Kyle D.; Holmes, Ross P.; Assimos, Dean G.

2011-01-01

Objectives Oxalate has been hypothesized to undergo absorption in the large and small intestine by both paracellular and transepithelial transport. Sucralose is a chlorinated sugar that is absorbed by paracellular mechanisms. This study's objective was to better understand intestinal oxalate transport by correlating oxalate and sucralose absorption in idiopathic calcium oxalate stone formers. Methods Idiopathic calcium oxalate stone formers were recruited to provide urine specimens on both a self-selected diet and following a meal containing 90 mg of 13C2-oxalate and 5 grams of sucralose, and a stool sample for determination of Oxalobacter formigenes colonization. The 24 hour urine collections were fractionated into the first 6 hours and the subsequent 18 hours. Sucralose and oxalate excretion were measured during these periods and used to estimate absorption. Results A total of 38 subjects were evaluated. The majority of both the 13C2-oxalate and sucralose absorption occurred within the 0-6 hour collection. The 13C2-oxalate and sucralose absorptions were significantly correlated at the 0-6 hour, the 6-24 hour, and the total 24 hour time periods (p<0.04). All five oxalate hyperabsorbers(> 15% absorption) also absorbed significantly more sucralose during the 0-6 hour and whole 24 hour time points (p<0.04). Oxalobacter formigenes colonization did not significantly alter oxalate absorption. Conclusion The results suggest that the majority of oxalate is absorbed in the proximal portion of the gastrointestinal tract and that paracelluar transport is involved. Augmented paracellular transport, as evidenced by increased sucralose absorption, may also influence oxalate absorption. PMID:21676449

Calcium oxalate monohydrate aggregation induced by aggregation of desialylated Tamm-Horsfall protein

PubMed Central

Viswanathan, Pragasam; Rimer, Jeffrey D.; Kolbach, Ann M.; Kleinman, Jack G.

2011-01-01

Tamm-Horsfall protein (THP) is thought to protect against calcium oxalate monohydrate (COM) stone formation by inhibiting COM aggregation. Several studies reported that stone formers produce THP with reduced levels of glycosylation, particularly sialic acid levels, which leads to reduced negative charge. In this study, normal THP was treated with neuraminidase to remove sialic acid residues, confirmed by an isoelectric point shift to higher pH. COM aggregation assays revealed that desialylated THP (ds-THP) promoted COM aggregation, while normal THP inhibited aggregation. The appearance of protein aggregates in solutions at ds-THP concentrations ≥1 µg/mL in 150 mM NaCl correlated with COM aggregation promotion, implying that ds-THP aggregation induced COM aggregation. The aggregation-promoting effect of the ds-THP was independent of pH above its isoelectric point, but was substantially reduced at low ionic strength, where protein aggregation was much reduced. COM aggregation promotion was maximized at a ds-THP to COM mass ratio of ~0.025, which can be explained by a model wherein partial COM surface coverage by ds-THP aggregates promotes crystal aggregation by bridging opposing COM surfaces, whereas higher surface coverage leads to repulsion between adsorbed ds-THP aggregates. Thus, desialylation of THP apparently abrogates a normal defensive action of THP by inducing protein aggregation, and subsequently COM aggregation, a condition that favors kidney stone formation. PMID:21229239

Kidney Stones in Primary Hyperoxaluria: New Lessons Learnt

PubMed Central

Jacob, Dorrit E.; Grohe, Bernd; Geßner, 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 patient’s medical therapy (treatment naïve 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 naïve 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 naïve 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

Lowering urinary oxalate excretion to decrease calcium oxalate stone disease

PubMed Central

Knight, John; Assimos, Dean G.

2016-01-01

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 1000–1200 mg/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

Reinjury risk of nano-calcium oxalate monohydrate and calcium oxalate dihydrate crystals on injured renal epithelial cells: aggravation of crystal adhesion and aggregation

PubMed Central

Gan, Qiong-Zhi; Sun, Xin-Yuan; Bhadja, Poonam; Yao, Xiu-Qiong; Ouyang, Jian-Ming

2016-01-01

Background Renal epithelial cell injury facilitates crystal adhesion to cell surface and serves as a key step in renal stone formation. However, the effects of cell injury on the adhesion of nano-calcium oxalate crystals and the nano-crystal-induced reinjury risk of injured cells remain unclear. Methods African green monkey renal epithelial (Vero) cells were injured with H2O2 to establish a cell injury model. Cell viability, superoxide dismutase (SOD) activity, malonaldehyde (MDA) content, propidium iodide staining, hematoxylin–eosin staining, reactive oxygen species production, and mitochondrial membrane potential (Δψm) were determined to examine cell injury during adhesion. Changes in the surface structure of H2O2-injured cells were assessed through atomic force microscopy. The altered expression of hyaluronan during adhesion was examined through laser scanning confocal microscopy. The adhesion of nano-calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) crystals to Vero cells was observed through scanning electron microscopy. Nano-COM and COD binding was quantitatively determined through inductively coupled plasma emission spectrometry. Results The expression of hyaluronan on the cell surface was increased during wound healing because of Vero cell injury. The structure and function of the cell membrane were also altered by cell injury; thus, nano-crystal adhesion occurred. The ability of nano-COM to adhere to the injured Vero cells was higher than that of nano-COD crystals. The cell viability, SOD activity, and Δψm decreased when nano-crystals attached to the cell surface. By contrast, the MDA content, reactive oxygen species production, and cell death rate increased. Conclusion Cell injury contributes to crystal adhesion to Vero cell surface. The attached nano-COM and COD crystals can aggravate Vero cell injury. As a consequence, crystal adhesion and aggregation are enhanced. These findings provide further insights into kidney stone

Distribution of organic matrix in calcium oxalate renal calculi.

PubMed

Warpehoski, M A; Buscemi, P J; Osborn, D C; Finlayson, B; Goldberg, E P

1981-01-01

The quantity of protein and carbohydrate comprising the matrix of calcium oxalate monohydrate (COM) renal stones was found to decrease with distance from the surface of the stone. The average organic concentration of stones 3 to 30 mm in diameter ranged from 5.7% at the surface to 2.7% at the core. This concentration gradient suggests matrix involvement in a "growth front" on stone surfaces with migration of organic material from the "older" interior. The matrix distribution was not readily correlated with density variations or with the presence of hydroxyapatite or calcium oxalate dihydrate. Surface matrix concentrations were greater than amounts predicted by physical adsorption. Electron microscopy confirmed the presence of the organic-rich surface layer and also suggested that increase in stone size occurs predominantly by crystal growth with microcrystal aggregates as growth centers.

Diversity in Protein Profiles of Individual Calcium Oxalate Kidney Stones

PubMed Central

Okumura, Nobuaki; Tsujihata, Masao; Momohara, Chikahiro; Yoshioka, Iwao; Suto, Kouzou; Nonomura, Norio; Okuyama, Akihiko; Takao, Toshifumi

2013-01-01

Calcium oxalate kidney stones contain low amounts of proteins, some of which have been implicated in progression or prevention of kidney stone formation. To gain insights into the pathophysiology of urolithiasis, we have characterized protein components of calcium oxalate kidney stones by proteomic approaches. Proteins extracted from kidney stones showed highly heterogeneous migration patterns in gel electrophoresis as reported. This was likely to be mainly due to proteolytic degradation and protein-protein crosslinking of Tamm-Horsfall protein and prothrombin. Protein profiles of calcium oxalate kidney stones were obtained by in-solution protease digestion followed by nanoLC-MALDI-tandem mass spectrometry, which resulted in identification of a total of 92 proteins in stones from 9 urolithiasis patients. Further analysis showed that protein species and their relative amounts were highly variable among individual stones. Although proteins such as prothrombin, osteopontin, calgranulin A and calgranulin B were found in most stones tested, some samples had high contents of prothrombin and osteopontin, while others had high contents of calgranulins. In addition, calgranulin-rich stones had various neutrophil-enriched proteins such as myeloperoxidase and lactotransferrin. These proteomic profiles of individual kidney stones suggest that multiple systems composed of different groups of proteins including leucocyte-derived ones are differently involved in pathogenesis of individual kidney stones depending on situations. PMID:23874695

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. Copyright © 2012 Elsevier B.V. All rights reserved.

Urinary stone composition in Israel: current status and variation with age and sex--a bicenter study.

PubMed

Usman, Kalba D; Golan, Shay; Abdin, Tamer; Livne, Pinhas M; Pode, Dov; Duvdevani, Mordechai; Lifshitz, David

2013-12-01

The epidemiologic data regarding stone composition in Israel are based on anachronistic methods of stone analysis. Historically, Israel was noted for an unusually high percentage of uric acid stones. The aim of the study was to describe the current stone composition distribution in Israel, using modern techniques of urinary stone analysis. Age and sex correlations were investigated. In a bicenter study, using infrared spectroscopy and X-ray diffraction, stones from five hundred and thirty eight (538) patients were analyzed and demographic data recorded. The study cohort included 401 men (74.5%) and 137 women (25.5%) with a male to female ratio of 2.9:1 and a median age of 48 years (range 2-85 years). While calcium oxalate monohydrate was the predominant component in both sexes, it was lower in female patients (77.3% vs 65%). The rate of infection stones (struvite+carbonate apatite) was significantly higher in women (35.7% vs 10.2%). Uric acid stones were found in only 14.5% of the patients and increased with age. Conversely, the rate of calcium oxalate dihydrate decreased with age. Modern techniques of urinary stone analysis showed that the most frequent stone component in Israel is calcium oxalate monohydrate. In contrast to earlier reports and in accordance with reports from other countries, the overall frequency of uric acid is 14.5%. With age, the frequency of uric acid increases reaching 21% in persons >60 years old. A significant sex difference was noted in the distribution of calcium oxalate stones and infection stones. The classic 3:1 ratio was maintained, however.

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.

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. Copyright © 2012 Elsevier B.V. All rights reserved.

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

Effect of animal and vegetable protein intake on oxalate excretion in idiopathic calcium stone disease.

PubMed

Marangella, M; Bianco, O; Martini, C; Petrarulo, M; Vitale, C; Linari, F

1989-04-01

Oxalate excretion was measured in healthy subjects and idiopathic calcium stone-formers on dietary regimens which differed in the type and amount of protein allowed; 24-h urine collections were obtained from 41 practising vegetarians and 40 normal persons on a free, mixed, "mediterranean" diet. Twenty idiopathic calcium stone-formers were also studied while on two low calcium, low oxalate diets which differed in that animal protein was high in one and restricted in the other. Vegetarians had higher urinary oxalate levels than controls and although the calcium levels were markedly lower, urinary saturation with calcium/oxalate was significantly higher. This mild hypercalciuria was interpreted as being secondary to both a higher intake and increased fractional intestinal absorption of oxalate. Changing calcium stone-formers from a high to a low animal protein intake produced a significant decrease in calcium excretion but there was no variation in urinary oxalate. As a result, the decrease in calcium oxalate saturation was only marginal and not significant. It was concluded that dietary animal protein has a minimal effect on oxalate excretion. Mild hyperoxaluria of idiopathic calcium stone disease is likely to be intestinal in origin. Calcium stone-formers should be advised to avoid an excess of animal protein but the risks of a vegetable-rich diet should also be borne in mind.

Crystal growth, structural, optical, thermal and dielectric properties of lithium hydrogen oxalate monohydrate single crystal

NASA Astrophysics Data System (ADS)

Chandran, Senthilkumar; Paulraj, Rajesh; Ramasamy, P.

2017-11-01

The vibrational groups of the lithium hydrogen oxalate monohydrate have been investigated by FTIR and FT- Raman analyses. It has low absorbance in the UV-Vis-NIR region. The laser damage threshold study confirms that the material withstands upto 30 mJ with time of 7 s, after that circular dot damage is seen on the surface. The dark region of the surface damage spot occurs due to the thermal effects. The material is thermally stable upto 93 °C and there is no weight loss below this temperature. The dielectric studies were carried out at the frequency regions of 1 kHz-1 MHz and different temperatures from 40 °C to 80 °C. Semi-organic non-linear optical (NLO) single crystal lithium hydrogen oxalate monohydrate has been grown by slow evaporation solution growth technique. The Hirshfeld surface analysis was performed to understand the different intermolecular interactions in the title compound. The fingerprint plots contain the highest portion of H⋯O/O⋯H (48.3%) interactions.

Nanoscale observations of the effect of citrate on calcium oxalate precipitation on calcite surfaces.

NASA Astrophysics Data System (ADS)

Burgos-Cara, Alejandro; Ruiz-Agudo, Encarnacion; Putnis, Christine V.

2016-04-01

Calcium oxalate (CaC2O4ṡxH2O) minerals are naturally occurring minerals found in fossils, plants, kidney stones and is a by-product in some processes such as paper, food and beverage production [1,2]. In particular, calcium oxalate monohydrate phase (COM) also known as whewellite (CaC2O4ṡH2O), is the most frequently reported mineral phase found in urinary and kidney stones together with phosphates. Organic additives are well known to play a key role in the formation of minerals in both biotic and abiotic systems, either facilitating their precipitation or hindering it. In this regard, recent studies have provided direct evidence demonstrating that citrate species could enhance dissolution of COM and inhibit their precipitation. [3,4] The present work aims at evauate the influence of pH, citrate and oxalic acid concentrations in calcium oxalate precipitation on calcite surfaces (Island Spar, Chihuahua, Mexico) through in-situ nanoscale observation using in situ atomic force microscopy (AFM, Multimode, Bruker) in flow-through experiments. Changes in calcium oxalate morphologies and precipitated phases were observed, as well as the inhibitory effect of citrate on calcium oxalate precipitation, which also lead to stabilization an the amorphous calcium oxalate phase. [1] K.D. Demadis, M. Öner, Inhibitory effects of "green"additives on the crystal growth of sparingly soluble salts, in: J.T. Pearlman (Ed.), Green Chemistry Research Trends, Nova Science Publishers Inc., New York, 2009, pp. 265-287. [2] M. Masár, M. Zuborová, D. Kaniansky, B. Stanislawski, Determination of oxalate in beer by zone electrophoresis on a chip with conductivity detection, J. Sep. Sci. 26 (2003) 647-652. [3] Chutipongtanate S, Chaiyarit S, Thongboonkerd V. Citrate, not phosphate, can dissolve calcium oxalate monohydrate crystals and detach these crystals from renal tubular cells. Eur J Pharmacol 2012;689:219-25. [4] Weaver ML, Qiu SR, Hoyer JR, Casey WH, Nancollas GH, De Yoreo JJ

Fourier transform infrared spectroscopy for analysis of kidney stones.

PubMed

Khan, Aysha Habib; Imran, Sheharbano; Talati, Jamsheer; Jafri, Lena

2018-01-01

To compare the results of a chemical method of kidney stone analysis with the results of Fourier transform infrared (FT-IR) spectroscopy. Kidney stones collected between June and October 2015 were simultaneously analyzed by chemical and FT-IR methods. Kidney stones (n=449) were collected from patients from 1 to 81 years old. Most stones were from adults, with only 11.5% from children (aged 3-16 years) and 1.5% from children aged <2 years. The male to female ratio was 4.6. In adults, the calcium oxalate stone type, calcium oxalate monohydrate (COM, n=224), was the most common crystal, followed by uric acid and calcium oxalate dihydrate (COD, n=83). In children, the most frequently occurring type was predominantly COD (n=21), followed by COM (n=11), ammonium urate (n=10), carbonate apatite (n=6), uric acid (n=4), and cystine (n=1). Core composition in 22 stones showed ammonium urate (n=2), COM (n=2), and carbonate apatite (n=1) in five stones, while uric acid crystals were detected (n=13) by FT-IR. While chemical analysis identified 3 stones as uric acid and the rest as calcium oxalate only. Agreement between the two methods was moderate, with a kappa statistic of 0.57 (95% confidence interval, 0.5-0.64). Disagreement was noted in the analysis of 77 stones. FT-IR analysis of kidney stones can overcome many limitations associated with chemical analysis.

Effect of Stone Size and Composition on Ultrasonic Propulsion Ex Vivo.

PubMed

Janssen, Karmon M; Brand, Timothy C; Bailey, Michael R; Cunitz, Bryan W; Harper, Jonathan D; Sorensen, Mathew D; Dunmire, Barbrina

2018-01-01

To evaluate in more detail the effectiveness of a new designed more efficient ultrasonic propulsion for large stones and specific stone compositions in a tissue phantom model. In the first clinical trial of noninvasive ultrasonic propulsion, urinary stones of unknown compositions and sizes up to 10 mm were successfully repositioned. The study included 8- to 12-mm stones of 4 different primary compositions (calcium oxalate monohydrate, ammonium acid urate, calcium phosphate, and struvite) and a renal calyx phantom consisting of a 12 mm × 30 mm well in a 10-cm block of tissue-mimicking material. Primary outcome was the number of times a stone was expelled over 10 attempts, with ultrasonic propulsion burst duration varying from 0.5 seconds to 5 seconds. Overall success rate at expelling stones was 95%. All calcium oxalate monohydrate and ammonium acid urate stones were expelled 100% of the time. The largest stone (12 mm) became lodged within the 12-mm phantom calyx 25% of the time regardless of the burst duration. With the 0.5-second burst, there was insufficient energy to expel the heaviest stone (0.88 g), but there was sufficient energy at the longer burst durations. With a single burst, ultrasonic propulsion successfully moved most stones at least 3 cm and, regardless of size or composition, expelled them from the calyx. Ultrasonic propulsion is limited to the stones smaller than the calyceal space, and for each burst duration, related to maximum stone mass. Published by Elsevier Inc.

Effect of Stone Size and Composition on Ultrasonic Propulsion Ex Vivo

PubMed Central

Janssen, Karmon M.; Brand, Timothy C.; Bailey, Michael R.; Cunitz, Bryan W.; Harper, Jonathan D.; Sorensen, Mathew D.; Dunmire, Barbrina

2018-01-01

OBJECTIVE To evaluate in more detail the effectiveness of a new designed more efficient ultrasonic propulsion for large stones and specific stone compositions in a tissue phantom model. In the first clinical trial of noninvasive ultrasonic propulsion, urinary stones of unknown compositions and sizes up to 10 mm were successfully repositioned. MATERIALS AND METHODS The study included 8- to 12-mm stones of 4 different primary compositions (calcium oxalate monohydrate, ammonium acid urate, calcium phosphate, and struvite) and a renal calyx phantom consisting of a 12 mm × 30 mm well in a 10-cm block of tissue-mimicking material. Primary outcome was the number of times a stone was expelled over 10 attempts, with ultrasonic propulsion burst duration varying from 0.5 seconds to 5 seconds. RESULTS Overall success rate at expelling stones was 95%. All calcium oxalate monohydrate and ammonium acid urate stones were expelled 100% of the time. The largest stone (12 mm) became lodged within the 12-mm phantom calyx 25% of the time regardless of the burst duration. With the 0.5-second burst, there was insufficient energy to expel the heaviest stone (0.88 g), but there was sufficient energy at the longer burst durations. CONCLUSION With a single burst, ultrasonic propulsion successfully moved most stones at least 3 cm and, regardless of size or composition, expelled them from the calyx. Ultrasonic propulsion is limited to the stones smaller than the calyceal space, and for each burst duration, related to maximum stone mass. PMID:28964820

The genetic composition of Oxalobacter formigenes and its relationship to colonization and calcium oxalate stone disease

PubMed Central

Knight, John; Deora, Rajendar; Assimos, Dean G.; Holmes, Ross P.

2013-01-01

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 stone disease. Protection against calcium oxalate stone disease appears to be due to the oxalate degradation that occurs in the gut on low calcium diets with a possible further contribution from intestinal oxalate secretion. Much remains to be learned about how the organism establishes and maintains gut colonization and the precise mechanisms by which it modifies stone risk. The sequencing and annotation of the genomes of a Group 1 and a Group 2 strain of O. formigenes should provide the informatic tools required for the identification of the genes and pathways associated with colonization and survival. In this review we have identified genes that may be involved and where appropriate suggested how they may be important in calcium oxalate stone disease. Elaborating the functional roles of these genes should accelerate our understanding of the organism and clarify its role in preventing stone formation. PMID:23632911

Evidence for net renal tubule oxalate secretion in patients with calcium kidney stones

PubMed Central

Zisman, Anna L.; Asplin, John R.; Worcester, Elaine M.; Coe, Fredric L.

2011-01-01

Little is known about the renal handling of oxalate in patients with idiopathic hypercalciuria (IH). To explore the role of tubular oxalate handling in IH and to evaluate whether differences exist between IH and normal controls, we studied 19 IH subjects, 8 normal subjects, and 2 bariatric stone formers (BSF) during a 1-day General Clinical Research Center protocol utilizing a low-oxalate diet. Urine and blood samples were collected at 30- to 60-min intervals while subjects were fasting and after they ate three meals providing known amounts of calcium, phosphorus, sodium, protein, oxalate, and calories. Plasma oxalate concentrations and oxalate-filtered loads were similar between patients (includes IH and BSF) and controls in both the fasting and fed states. Urinary oxalate excretion was significantly higher in patients vs. controls regardless of feeding state. Fractional excretion of oxalate (FEOx) was >1, suggesting tubular secretion of oxalate, in 6 of 19 IH and both BSF, compared with none of the controls (P < 0.00001). Adjusted for water extraction along the nephron, urine oxalate rose more rapidly among patients than normal subjects with increases in plasma oxalate. Our findings identify tubular secretion of oxalate as a key mediator of hyperoxaluria in calcium stone formers, potentially as a means of maintaining plasma oxalate in a tight range. PMID:21123489

Novel porcine model for calcium oxalate stone formation.

PubMed

Trojan, Brandon P; Trojan, Sara J; Navetta, Andrew; Staches, Bryce; Sutton, Bryan; Filleur, Stephanie; Nelius, Thomas

2017-10-01

Mechanisms for calcium-based stone formation are not clearly delineated. Porcine are the most anatomically and physiologically congruent mammal to humans. Our objectives were to develop a cost-effective and easily reproducible porcine model for the study of calcium-based nephrolithiasis. Crossbred male pigs (n = 16) were assigned randomly to one of the following treatments: (1) control; (2) ethylene glycol (EG) + vitamin D (VD); (3) EG + ammonium chloride (AC); (4) EG + gentamicin (G); (5) EG + Lasix; (6) EG + VD + AC; (7) EG + VD + G. Treatments were administered for 28 days; blood and urine were collected on day 0, 14, and 28. At the endpoint of the study, renal tissue was collected for gross and microscopic analysis of crystal stone formation and inflammation. Stone-forming parameters were observed in serum and urine. For control versus all other treatments, by day 28, serum BUN and creatinine were less (P < 0.01), urinary creatinine, citrate and pH were greater (P < 0.01), and urinary oxalate was less (P < 0.01). Histopathological analysis of H&E staining and stone analysis revealed formation of calcium oxalate stones and crystal formation within the renal cortex and medulla for all animals except control. Nephrotoxicity was observed in one animal from treatment EG + G. The treatments explored in this experiment provided novel examples of cost-effective porcine models for the study of nephrolithiasis. EG + VD had the strongest indicators of nephrolithiasis without nephrotoxicity.

In Idiopathic Calcium Oxalate Stone Formers, Unattached Stones Show Evidence of Having Originated as Attached Stones on Randall’s Plaque

PubMed Central

Miller, Nicole L.; Williams, James C.; Evan, Andrew P.; Bledsoe, Sharon B.; Coe, Fredric L.; Worcester, Elaine M.; Munch, Larry C.; Handa, Shelly E.; Lingeman, James E.

2009-01-01

Objective To analyze the structure and composition of unattached stones in idiopathic calcium oxalate stone formers (ICSF) and compare them to attached stones from the same cohort in order to investigate whether more than one pathogenic mechanism exists for stone formation in ICSF. Patients and methods ICSF undergoing percutaneous nephrolithotomy or ureteroscopy for treatment of nephrolithiasis were consented for this study. All accessible renal papillae were endoscopically imaged using a digital endoscope. All stones were removed and determined by the operating surgeon to be attached or unattached to the underlying papilla. Micro-computed tomography (micro-CT), which provides three-dimensional analysis of entire stones, was used to compare the structure and composition of attached versus unattached stones. Results Of 115 stones collected from 9 patients (12 renal units), only 25 stones were found not to be attached to renal papillae. Of these 25 stones, 4 were lost and 12 showed definite morphological evidence of having been attached to tissue, probably having been knocked off of papillae during access. For the remaining 9 stones, micro-CT analysis revealed at least one internal region of calcium phosphate within each of these unattached calcium oxalate (CaOx) stones. That is, the internal structure of the unattached stones is consistent with their having originated attached to RP, and then having become detached but retained in the kidney, with new layers of CaOx eventually covering the original attachment site. Conclusions Micro CT analysis supports the hypothesis that in ICSF, both attached and unattached stones occur as a result of a common pathogenic mechanism. That is, in this type of stone former, CaOx stones—even those not showing morphology that betrays attachment—all originate attached to interstitial plaque on the renal papilla. PMID:19549258

The Effect of Stone Composition on the Efficacy of Retrograde Intrarenal Surgery: Kidney Stones 1 - 3 cm in Diameter.

PubMed

Xue, Yuquan; Zhang, Peng; Yang, Xiaojie; Chong, Tie

2015-05-01

The goal of this study was to analyze the effect of stone composition on the efficacy of retrograde intrarenal surgery (RIRS) with kidney stones of 1-3 cm, 1-2 cm, and 2-3 cm in diameter. We undertook a retrospective analysis of 74 patients with kidney stones who underwent RIRS. The patients were divided into two groups based on stone composition: Group I (n=47) (calcium oxalate monohydrate and calcium phosphate) was the hard to fragment stone group and group II (n=27) (calcium oxalate dihydrate, magnesium ammonium phosphate, and uric acid) was the easy to fragment stone group. Forty-six patients with kidney stones 1 to 2 cm in diameter were divided into group A (n=30) (smaller than 20 mm, hard to fragment stones) and group B (n=16) (smaller than 20 mm, easy to fragment stones). Twenty-eight patients with stones 2 to 3 cm in diameter were divided into group C (n=17) (larger than 20 mm, hard to fragment stones) and group D (n=11) (larger than 20 mm, easy-to-crush stones). The stone clearance rates of group I and group II were 66.0% and 88.9%, respectively (P<0.05). The stone clearance rates of group A and group B were 73.3% and 100% (P<0.05). The stone clearance rates of group C and group D were 52.9% and 72.7%, respectively. Stone composition has a significant impact on the efficacy of RIRS in the management of 1 to 3 cm kidney stones. For 2-3 cm calcium oxalate dihydrate stones, uric acid stones, and magnesium ammonium phosphate stones, the outcome of RIRS treatment was relatively good, and RIRS is recommended.

Effect of vitamin C supplements on urinary oxalate and pH in calcium stone-forming patients.

PubMed

Baxmann, Alessandra Calábria; De O G Mendonça, Claudia; Heilberg, Ita Pfeferman

2003-03-01

The contribution of ascorbate to urinary oxalate is controversial. The present study aimed to determine whether urinary oxalate and pH may be affected by vitamin C supplementation in calcium stone-forming patients. Forty-seven adult calcium stone-forming patients received either 1 g (N=23) or 2 g (N=24) of vitamin C supplement for 3 days and 20 healthy subjects received 1 g. A 24-hour urine sample was obtained both before and after vitamin C for calcium, oxalate, magnesium, citrate, sodium, potassium, and creatinine determination. The Tiselius index was used as a calcium oxalate crystallization index. A spot fasting morning urine sample was also obtained to determine the urinary pH before and after vitamin C. Fasting urinary pH did not change after 1 g (5.8 +/- 0.6 vs. 5.8 +/- 0.7) or 2 g vitamin C (5.8 +/- 0.8 vs. 5.8 +/- 0.7). A significant increase in mean urinary oxalate was observed in calcium stone-forming patients receiving either 1 g (50 +/- 16 vs. 31 +/- 12 mg/24 hours) or 2 g (48 +/- 21 vs. 34 +/- 12 mg/24 hours) of vitamin C and in healthy subjects (25 +/- 12 vs. 39 +/- 13 mg/24 hours). A significant increase in mean Tiselius index was observed in calcium stone-forming patients after 1 g (1.43 +/- 0.70 vs. 0.92 +/- 0.65) or 2 g vitamin C (1.61 +/- 1.05 vs. 0.99 +/- 0.55) and in healthy subjects (1.50 +/- 0.69 vs. 0.91 +/- 0.46). Ancillary analyses of spot urine obtained after vitamin C were performed in 15 control subjects in vessels with or without ethylenediaminetetraacetic acid (EDTA) with no difference in urinary oxalate between them (28 +/- 23 vs. 26 +/- 21 mg/L), suggesting that the in vitro conversion of ascorbate to oxalate did not occur. These data suggest that vitamin C supplementation may increase urinary oxalate excretion and the risk of calcium oxalate crystallization in calcium stone-forming patients.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 environmentmore » 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.« less

Estimation of urinary stone composition by automated processing of CT images.

PubMed

Chevreau, Grégoire; Troccaz, Jocelyne; Conort, Pierre; Renard-Penna, Raphaëlle; Mallet, Alain; Daudon, Michel; Mozer, Pierre

2009-10-01

The objective of this article was developing an automated tool for routine clinical practice to estimate urinary stone composition from CT images based on the density of all constituent voxels. A total of 118 stones for which the composition had been determined by infrared spectroscopy were placed in a helical CT scanner. A standard acquisition, low-dose and high-dose acquisitions were performed. All voxels constituting each stone were automatically selected. A dissimilarity index evaluating variations of density around each voxel was created in order to minimize partial volume effects: stone composition was established on the basis of voxel density of homogeneous zones. Stone composition was determined in 52% of cases. Sensitivities for each compound were: uric acid: 65%, struvite: 19%, cystine: 78%, carbapatite: 33.5%, calcium oxalate dihydrate: 57%, calcium oxalate monohydrate: 66.5%, brushite: 75%. Low-dose acquisition did not lower the performances (P < 0.05). This entirely automated approach eliminates manual intervention on the images by the radiologist while providing identical performances including for low-dose protocols.

Substituting milk for apple juice does not increase kidney stone risk in most normocalciuric adults who form calcium oxalate stones.

PubMed

Massey, L K; Kynast-Gales, S A

1998-03-01

Increasing intake of dietary calcium from less than 400 mg to 800 mg daily may decrease the absorption of dietary oxalate, which in turn would decrease urinary oxalate excretion. The effect of substituting milk for apple juice on urine composition and risk of calcium oxalate precipitability was studied. Twenty-one normocalciuric adults with a history of at least 1 calcium oxalate stone and urinary oxalate excretion exceeding 275 micromol/day on their self-selected diet. Randomized crossover trial. Each participant consumed two moderate-oxalate (2,011 micromol/day) study diets, which were identical except that one contained 360 mL milk and the other contained 540 mL apple juice as the beverage with meals. Four days free-living then 2 days in the metabolic unit of a university nutrition department. Tiselius risk index for calcium oxalate precipitability calculated from urine composition. Paired t tests. Twenty-four hour urinary oxalate excretion was 18% lower (P<.0001) on the milk diet vs the juice diet: 423 vs 514 micromol, respectively. Calcium excretion was 17% higher (P<.05) on the milk vs juice diet: 4.7 vs 3.9 mmol, respectively. Urinary magnesium and citrate excretion, volume, and Tiselius risk index did not differ between diets. Substituting 360 mL milk daily for apple juice with meals in a diet containing moderate amounts of dietary oxalate from whole grains, legumes, fruits, and vegetables does not increase the risk index of calcium oxalate precipitability in most normocalciuric adults who form stones.

Proteomic analysis of a rare urinary stone composed of calcium carbonate and calcium oxalate dihydrate: a case report.

PubMed

Kaneko, Kiyoko; Matsuta, Yosuke; Moriyama, Manabu; Yasuda, Makoto; Chishima, Noriharu; Yamaoka, Noriko; Fukuuchi, Tomoko; Miyazawa, Katsuhito; Suzuki, Koji

2014-03-01

The objective of the present study was to investigate the matrix protein of a rare urinary stone that contained calcium carbonate. A urinary stone was extracted from a 34-year-old male patient with metabolic alkalosis. After X-ray diffractometry and infrared analysis of the stone, proteomic analysis was carried out. The resulting mass spectra were evaluated with protein search software, and matrix proteins were identified. X-ray diffraction and infrared analysis confirmed that the stone contained calcium carbonate and calcium oxalate dihydrate. Of the identified 53 proteins, 24 have not been previously reported from calcium oxalate- or calcium phosphate-containing stones. The protease inhibitors and several proteins related to cell adhesion or the cytoskeleton were identified for the first time. We analyzed in detail a rare urinary stone composed of calcium carbonate and calcium oxalate dihydrate. Considering the formation of a calcium carbonate stone, the new identified proteins should play an important role on the urolithiasis process in alkaline condition. © 2013 The Japanese Urological Association.

Crystal growth, piezoelectric, non-linear optical and mechanical properties of lithium hydrogen oxalate monohydrate single crystal

NASA Astrophysics Data System (ADS)

Chandran, Senthilkumar; Paulraj, Rajesh; Ramasamy, P.

2017-05-01

Semi-organic lithium hydrogen oxalate monohydrate non-linear optical single crystals have been grown by slow evaporation solution growth technique at 35 °C. Single crystal X-ray diffraction study showed that the grown crystal belongs to the triclinic system with space group P1. The mechanical strength decreases with increasing load. The piezoelectric coefficient is found to be 1.41 pC/N. The nonlinear optical property was measured using Kurtz Perry powder technique and SHG efficiency was almost equal to that of KDP.

Analysis of stone fragility in vitro and in vivo with piezoelectric shock waves using the EDAP LT-01.

PubMed

Wang, Y H; Grenabo, L; Hedelin, H; Pettersson, S; Wikholm, G; Zachrisson, B F

1993-04-01

A total of 100 whole stones was fragmented in vitro at 3-minute intervals with piezoelectric shock waves using the EDAP LT-01 device until all fragments were less than 2 mm. Larger stones and stones with a high computerized tomography attenuation needed longer treatments for fragmentation. Smoothly bulging stones with an even structure according to plain x-ray films were also more resistant to the shock wave treatment. Calcium oxalate monohydrate stones were not more difficult to break than other types of calculi. Stone fragments from 100 patients after extracorporeal shock wave lithotripsy were also analyzed. The average size of the fragments collected was less than 1 mm. Larger stones produced larger fragments and required more treatment sessions.

Renal geology (quantitative renal stone analysis) by 'Fourier transform infrared spectroscopy'.

PubMed

Singh, Iqbal

2008-01-01

To prospectively determine the precise stone composition (quantitative analysis) by using infrared spectroscopy in patients with urinary stone disease presenting to our clinic. To determine an ideal method for stone analysis suitable for use in a clinical setting. After routine and a detailed metabolic workup of all patients of urolithiasis, stone samples of 50 patients of urolithiasis satisfying the entry criteria were subjected to the Fourier transform infrared spectroscopic analysis after adequate sample homogenization at a single testing center. Calcium oxalate monohydrate and dihydrate stone mixture was most commonly encountered in 35 (71%) followed by calcium phosphate, carbonate apatite, magnesium ammonium hexahydrate and xanthine stones. Fourier transform infrared spectroscopy allows an accurate, reliable quantitative method of stone analysis. It also helps in maintaining a computerized large reference library. Knowledge of precise stone composition may allow the institution of appropriate prophylactic therapy despite the absence of any detectable metabolic abnormalities. This may prevent and or delay stone recurrence.

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. Copyright © 2014 Elsevier B.V. All rights reserved.

Risk Factors for Stone Recurrence after Percutaneous Nephrolithotomy

NASA Astrophysics Data System (ADS)

Krambeck, Amy E.; Rangel, Laureano J.; LeRoy, Andrew J.; Patterson, David E.; Gettman, Matthew T.

2008-09-01

Recent studies have demonstrated more than 30% of percutaneous nephrolithotomy (PCNL) patients will experience a stone recurrence over a 20 year period. The goal of our study was to identify risk factors for stone recurrence after PCNL. Chart review identified 754 patients treated with PCNL for urolithiasis from March of 1983 to July 1984 at our institution. Of this cohort, 87 patients continued to receive medical care at our clinic and had been evaluated within the last 5 years. Of the 87 patients, 80 had recent radiographic imaging. Average follow-up was 19.2 years and 32 (40.0%) experienced at least 1 stone recurrence. There was no difference in preoperative BMI (p = 0.453) or change in BMI (p = 0.964) between patients that did and did not have a stone recurrence. Renal stone location (p = 0.605) and stone size (p = 0.238) were not predictive of recurrence. Patients with calcium oxalate monohydrate stones were less likely to recur (38.7% vs. 41.6%, p = 0.004) and those with calcium oxalate dihydrate (COD) were more likely to recur (31.1% vs. 19.6%, p = 0.006) compared to other compositions. Diabetes mellitus was not associated with recurrent stones (p = 0.810). Those patients with residual stones or fragments <3 mm were more likely to recur and to recur earlier than patients rendered entirely stone free at time of PCNL (p = 0.015). Stone recurrences were associated with the late development of renal insufficiency (25% vs. 2.1%, p = 0.002). In conclusion, stone composition, as well as the presence of residual fragments was associated with recurrent symptomatic stone events after PCNL. Recurrent stone events were significantly associated with the risk of developing renal insufficiency, further stressing the need for complete stone clearance at time of PCNL.

Phase composition and morphological characterization of human kidney stones using IR spectroscopy, scanning electron microscopy and X-ray Rietveld analysis.

PubMed

Chatterjee, Paramita; Chakraborty, Arup; Mukherjee, Alok K

2018-07-05

Pathological calcification in human urinary tract (kidney stones) is a common problem affecting an increasing number of people around the world. Analysis of such minerals or compounds is of fundamental importance for understanding their etiology and for the development of prophylactic measures. In the present study, structural characterization, phase quantification and morphological behaviour of thirty three (33) human kidney stones from eastern India have been carried out using IR spectroscopy (FT-IR), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). Quantitative phase composition of kidney stones has been analyzed following the Rietveld method. Based on the quantitative estimates of constituent phases, the calculi samples have been classified into oxalate (OX), uric acid (UA), phosphate (PH) and mixed (MX) groups. Rietveld analysis of PXRD patterns showed that twelve (36%) of the renal calculi were composed exclusively of whewellite (calcium oxalate monohydrate, COM). The remaining twenty one (64%) stones were mixture of phases with oxalate as the major constituent in fourteen (67%) of these stones. The average crystallite size of whewellite in oxalate stones, as determined from the PXRD analysis, varies between 93 (1) nm and 202 (3) nm, whereas the corresponding sizes for the uric acid and struvite crystallites in UA and PH stones are 79 (1)-155 (4) nm and 69 (1)-123(1) nm, respectively. The size of hydroxyapatite crystallites, 10 (1)-21 (1) nm, is smaller by about one order of magnitude compared to other minerals in the kidney stones. A statistical analysis using fifty (50) kidney stones (33 calculi from the present study and 17 calculi reported earlier from our laboratory) revealed that the oxalate group (whewellite, weddellite or mixture of whewellite and weddellite as the major constituent) is the most prevalent (82%) kidney stone type in eastern India. Copyright © 2018 Elsevier B.V. All rights reserved.

A crude protective film on historic stones and its artificial preparation through biomimetic synthesis

NASA Astrophysics Data System (ADS)

Liu, Qiang; Zhang, Bingjian; Shen, Zhongyue; Lu, Huanming

2006-12-01

A biomimetic film has been found on the surface of the historic stone buildings and monuments. The stone inscriptions under the film are preserved so well that has not been damaged for more than 1000 years. Samples of the crude film have been analyzed by XRD, FTIR, PLM, EDA, SEM and TEM. The results show that it consists mainly of calcium oxalate monohydrate. On the basis of the existence of the organism debris, it is concluded that the film should be a product of biomineralization. According to this hypothesis, a similar film has been prepared on the stone surface through biomimetic synthesis in our laboratory. The preliminary analysis shows that the artificial protective film functions well.

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

Distinguishing characteristics of idiopathic calcium oxalate kidney stone formers with low amounts of Randall's plaque.

PubMed

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

2014-10-07

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. 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. 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 (187±86 mg versus 291±99 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. 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. Copyright © 2014 by the American Society of Nephrology.

Protective Effects of Pistacia lentiscus L. fruit extract against calcium oxalate monohydrate induced proximal tubular injury.

PubMed

Cheraft-Bahloul, Nassima; Husson, Cécile; Ourtioualous, Meriam; Sinaeve, Sébastien; Atmani, Djebbar; Stévigny, Caroline; Nortier, Joëlle L; Antoine, Marie-Hélène

2017-09-14

The world prevalence of kidney stones is increasing and plants are frequently used to treat urolithiasis. Pistacia lentiscus L, a plant which freely grows around the Mediterranean basin areas, is widely used for various pathologies. P. lentiscus has an important impact as it has economical value on top of its pharmacological interest. Decoctions of its aerial parts and/or resin are used to treat kidney stones. To in vitro assess the potential nephroprotective effect of Pistacia lentiscus ethanolic fruit extract (PLEF) on proximal tubular cells in response to the adhesion of calcium oxalate monohydrate (COM) crystals. Human Kidney [HK]-2 cells were incubated with and without COM in the presence or absence of PLEF. Cell viability was measured by the resazurin assay. The expression of E-cadherin was analyzed by PCR. The extracellular production of H 2 O 2 was measured by Amplex® Red H 2 O 2 Assay. The numbers of detached or non-adherent COM crystals in the presence of PLEF were microscopically captured and counted using ImageJ software. The interaction of PLEF with COM and the effect of PLEF on crystal size were analyzed by flow cytometry. The spectrophotometric measurement of turbidity was performed for assessing the COM concentration. PLEF incubated with COM was able to increase the cell viability. The decrease of E-cadherin expression after incubation with COM was counteracted by PLEF. Overproduction of H 2 O 2 induced by COM was also inhibited by PLEF. Observations using flow cytometry showed that interactions between PLEF and the COM crystals occurred. PLEF was also effective in reducing the particles size and in lowering COM concentration. Our data show that COM tubulotoxicity can be significantly reversed by PLEF -at least in part- via an inhibition of COM crystals adhesion onto the apical membrane. This early beneficial effect of PLEF needs to be further investigated as a useful strategy in nephrolithiasis prevention. Copyright © 2017 Elsevier Ireland Ltd

Imaging-based assessment of the mineral composition of urinary stones: an in vitro study of the combination of hounsfield unit measurement in noncontrast helical computerized tomography and the twinkling artifact in color Doppler ultrasound.

PubMed

Hassani, Hakim; Raynal, Gauthier; Spie, Romain; Daudon, Michel; Vallée, Jean-Noël

2012-05-01

We evaluated the value of combining noncontrast helical computerized tomography (NCHCT) and color Doppler ultrasound in the assessment of the composition of urinary stones. In vitro, we studied 120 stones of known composition, that separate into the five main types: 18 calcium oxalate monohydrate (COM) stones, 41 calcium oxalate dihydrate (COD) stones, 24 uric acid stones, 25 calcium phosphate stones and 12 cystine calculi. Stones were characterized in terms of their Hounsfield density (HU) in NCHCT and the presence of a twinkling artifact (TA) in color Doppler ultrasound. There were statistically significant HU differences between calcium and non-calcium stones (p < 0.001), calcium oxalate stones and calcium phosphate stones (p < 0.001) and uric acid stones and cystine calculi (p < 0.001) but not between COM and COD stones (p = 0.786). Hence, the HU was a predictive factor of the composition of all types of stones, other than for COM and COD stones within the calcium oxalate class (p > 0.05). We found that the TA does not enable differentiation between calcium and non-calcium stones (p > 0.999), calcium oxalate stones and calcium phosphate stones (p = 0.15), or uric acid stones and cystine calculi (p = 0.079). However, it did reveal a significant difference between COM and COD stones (p = 0.002). The absence of a TA is a predictive factor for the presence of COM stones (p = 0.008). Hence, the association of NCHCT and Doppler enables the accurate classification of the five types of stones in vitro. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Antioxidant properties of polysaccharide from the brown seaweed Sargassum graminifolium (Turn.), and its effects on calcium oxalate crystallization.

PubMed

Zhang, Chao-Yan; Wu, Wen-Hui; Wang, Jue; Lan, Min-Bo

2012-01-01

We investigated the effects of polysaccharides from the brown seaweed Sargassum graminifolium (Turn.) (SGP) on calcium oxalate crystallization, and determined its antioxidant activities. To examine the effects of SGP on calcium oxalate crystallization, we monitored nucleation and aggregation of calcium oxalate monohydrate crystals, using trisodium citrate as a positive control. We assessed antioxidant activities of SGP by determining its reducing power, its ability to scavenge superoxide radicals, and its activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The nucleation inhibition ratio of trisodium citrate and SGP was 58.5 and 69.2%, respectively, and crystal aggregation was inhibited by 71.4 and 76.8%, respectively. Increasing concentrations of SGP resulted in increased scavenging of superoxide anions and DPPH radicals (IC₅₀ = 1.9 and 0.6 mg/mL, respectively). These results suggest that SGP could be a candidate for treating urinary stones because of its ability to inhibit calcium oxalate crystallization and its antioxidant properties.

Antioxidant Properties of Polysaccharide from the Brown Seaweed Sargassum graminifolium (Turn.), and Its Effects on Calcium Oxalate Crystallization

PubMed Central

Zhang, Chao-Yan; Wu, Wen-Hui; Wang, Jue; Lan, Min-Bo

2012-01-01

We investigated the effects of polysaccharides from the brown seaweed Sargassum graminifolium (Turn.) (SGP) on calcium oxalate crystallization, and determined its antioxidant activities. To examine the effects of SGP on calcium oxalate crystallization, we monitored nucleation and aggregation of calcium oxalate monohydrate crystals, using trisodium citrate as a positive control. We assessed antioxidant activities of SGP by determining its reducing power, its ability to scavenge superoxide radicals, and its activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The nucleation inhibition ratio of trisodium citrate and SGP was 58.5 and 69.2%, respectively, and crystal aggregation was inhibited by 71.4 and 76.8%, respectively. Increasing concentrations of SGP resulted in increased scavenging of superoxide anions and DPPH radicals (IC50 = 1.9 and 0.6 mg/mL, respectively). These results suggest that SGP could be a candidate for treating urinary stones because of its ability to inhibit calcium oxalate crystallization and its antioxidant properties. PMID:22363225

Gut microbiota and oxalate homeostasis

PubMed Central

2017-01-01

This perspective focuses on how the gut microbiota can impact urinary oxalate excretion in the context of hyperoxaluria, a major risk factor in kidney stone disease. In the genetic disease of Primary Hyperoxaluria Type 1 (PH1), an increased endogenous production of oxalate, due to a deficiency of the liver enzyme alanine-glyoxylate aminotransferase (AGT), results in hyperoxaluria and oxalate kidney stones. The constant elevation in urinary oxalate in PH1 patients ultimately leads to tissue deposition of oxalate, renal failure and death and the only known cure for PH1 is a liver or liver-kidney transplant. The potential impact of a probiotic/therapeutic approach may be clinically significant in PH1 and could also extend to a much larger population of idiopathic oxalate stone formers who comprise ~12% of Americans, individuals with enteric hyperoxaluria, and an emerging population of hyperoxaluric patients who have undergone bariatric surgery and develop kidney stone disease as a consequence. PMID:28217701

Gut microbiota and oxalate homeostasis.

PubMed

Hatch, Marguerite

2017-01-01

This perspective focuses on how the gut microbiota can impact urinary oxalate excretion in the context of hyperoxaluria, a major risk factor in kidney stone disease. In the genetic disease of Primary Hyperoxaluria Type 1 (PH1), an increased endogenous production of oxalate, due to a deficiency of the liver enzyme alanine-glyoxylate aminotransferase (AGT), results in hyperoxaluria and oxalate kidney stones. The constant elevation in urinary oxalate in PH1 patients ultimately leads to tissue deposition of oxalate, renal failure and death and the only known cure for PH1 is a liver or liver-kidney transplant. The potential impact of a probiotic/therapeutic approach may be clinically significant in PH1 and could also extend to a much larger population of idiopathic oxalate stone formers who comprise ~12% of Americans, individuals with enteric hyperoxaluria, and an emerging population of hyperoxaluric patients who have undergone bariatric surgery and develop kidney stone disease as a consequence.

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

Calcium oxalate stone formation in the inner ear as a result of an Slc26a4 mutation.

PubMed

Dror, Amiel A; Politi, Yael; Shahin, Hashem; Lenz, Danielle R; Dossena, Silvia; Nofziger, Charity; Fuchs, Helmut; Hrabé de Angelis, Martin; Paulmichl, Markus; Weiner, Steve; Avraham, Karen B

2010-07-09

Calcium oxalate stone formation occurs under pathological conditions and accounts for more than 80% of all types of kidney stones. In the current study, we show for the first time that calcium oxalate stones are formed in the mouse inner ear of a genetic model for hearing loss and vestibular dysfunction in humans. The vestibular system within the inner ear is dependent on extracellular tiny calcium carbonate minerals for proper function. Thousands of these biominerals, known as otoconia, are associated with the utricle and saccule sensory maculae and are vital for mechanical stimulation of the sensory hair cells. We show that a missense mutation within the Slc26a4 gene abolishes the transport activity of its encoded protein, pendrin. As a consequence, dramatic changes in mineral composition, size, and shape occur within the utricle and saccule in a differential manner. Although abnormal giant carbonate minerals reside in the utricle at all ages, in the saccule, a gradual change in mineral composition leads to a formation of calcium oxalate in adult mice. By combining imaging and spectroscopy tools, we determined the profile of mineral composition and morphology at different time points. We propose a novel mechanism for the accumulation and aggregation of oxalate crystals in the inner ear.

[A new approach to urinary stone analysis according to the combination of the components: experience with 7949 cases].

PubMed

Millán, F; Gracia, S; Sánchez-Martín, F M; Angerri, O; Rousaud, F; Villavicencio, H

2011-03-01

To evaluate a new approach to urinary stone analysis according to the combination of the components. A total of 7949 stones were analysed and their main components and combinations of components were classified according to gender and age. Statistical analysis was performed using the chi-square test. Calcium oxalate monohydrate (COM) was the most frequent component in both males (39%) and females (37.4%), followed by calcium oxalate dihydrate (COD) (28%) and uric acid (URI) (14.6%) in males and by phosphate (PHO) (22.2%) and COD (19.6%) in females (p=0.0001). In young people, COD and PHO were the most frequent components in males and females respectively (p=0.0001). In older patients, COM and URI (in that order) were the most frequent components in both genders (p=0.0001). COM is oxalate dependent and is related to diets with a high oxalate content and low water intake. The progressive increase in URI with age is related mainly to overweight and metabolic syndrome. Regarding the combinations of components, the most frequent were COM (26.3%), COD+Apatite (APA) (15.5%), URI (10%) and COM+COD (7.5%) (p=0.0001). This study reports not only the composition of stones but also the main combinations of components according to age and gender. The results prove that stone composition is related to the changes in dietary habits and life-style that occur over a lifetime, and the morphological structure of stones is indicative of the aetiopathogenic mechanisms. Copyright © 2010 AEU. Published by Elsevier Espana. All rights reserved.

The Association of Household Food Insecurity and the Risk of Calcium Oxalate Stones.

PubMed

Shafi, Hamid; Dorosty Motlagh, Ahmad-Reza; Bagherniya, Mohammad; Daeezadeh, Atefeh; Safarian, Mohammad

2017-08-29

Food insecurity has been defined as 'limited or uncertain availability of nutritionally adequate and safe foods', which associated with adverse health consequences in human. Another alarming condition, which is related to several comorbidities is kidney stone. This study aimed to determine the association of household food insecurity and developing kidney stones (calcium oxalate) in adults referred to medical centers of Babol. This case-control study included 200 participants 18-65 years of ages (100 cases, 100 controls). An 18-items food insecurity questionnaire (USDA), a valid and reliable 147-item food frequency questionnaire (FFQ) and demographic characteristics were obtained via interviewing. Sixty eight percent of cases and 40% of controls were food insecure, respectively. Food insecurity was significantly associated with the risk of kidney stone (P < .05). Furthermore, body mass index (BMI) and family history of kidney stone were significantly associated with the risk of kidney stones (P < .05). Food insecurity and BMI were significantly associated with the kidney stone, which shows the importance of availability of nutritionally adequate and safe foods in prevention of the kidney stone.

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.

Serum Estradiol and Testosterone Levels in Kidney Stones Disease with and without Calcium Oxalate Components in Naturally Postmenopausal Women

PubMed Central

Ou, Lili; Duan, Xiaolu; Zeng, Guohua

2013-01-01

Objective Epidemiological data reveal that the overall risk for kidney stones disease is lower for women compared to age-matched men. However, the beneficial effect for the female sex is lost upon menopause, a time corresponding to the onset of fall in estrogen levels. The aim of this study was to describe the serum estradiol (E2) and testosterone (T) characteristics of naturally postmenopausal women with kidney stones. Methods 113 naturally postmenopausal women with newly diagnosed kidney stones (aged 57.4±4.98 years) and 84 age frequency matched stone-free controls (56.9±4.56 years) were validly recruited in the case-control study. The odds ratios (ORs) for the associations between sex hormones and kidney stones were estimated with logistic regression models, adjusting for demographic data and medical history. Patients were also stratified analyzed according to stone components (calcium oxalate stones [COS]; non-calcium oxalate stones [NCOS]). Results Serum E2 (21.1 vs. 31.1 pg/ml) was significantly lower in kidney stones patients compared to controls. Post-hoc analysis demonstrated that this effect was driven by COS patients (p<0.001). According to tertiles of the E2 levels, a significant higher frequency of COS was seen in the lowest E2 group (p <0.001). Multiple logistic regression analysis identified E2 level as a strong factor that was independently associated with the risk for COS (per 1 SD increase, OR=0.951, 95% confidence interval [CI] = 0.919-0.985; highest: lowest tertile, OR=0.214, 95%CI = 0.069-0.665). However, serum T levels did not significantly differ among the groups. Conclusions Naturally postmenopausal women with higher remaining estradiol levels appear less likely to suffer from kidney calcium oxalate stones. However, no correlation was found between serum T level and kidney stones. These findings support the hypothesis that higher postmenopausal endogenous estrogens may protect against kidney stones with ageing. PMID:24086550

Serum estradiol and testosterone levels in kidney stones disease with and without calcium oxalate components in naturally postmenopausal women.

PubMed

Zhao, Zhijian; Mai, Zanlin; Ou, Lili; Duan, Xiaolu; Zeng, Guohua

2013-01-01

Epidemiological data reveal that the overall risk for kidney stones disease is lower for women compared to age-matched men. However, the beneficial effect for the female sex is lost upon menopause, a time corresponding to the onset of fall in estrogen levels. The aim of this study was to describe the serum estradiol (E2) and testosterone (T) characteristics of naturally postmenopausal women with kidney stones. 113 naturally postmenopausal women with newly diagnosed kidney stones (aged 57.4±4.98 years) and 84 age frequency matched stone-free controls (56.9±4.56 years) were validly recruited in the case-control study. The odds ratios (ORs) for the associations between sex hormones and kidney stones were estimated with logistic regression models, adjusting for demographic data and medical history. Patients were also stratified analyzed according to stone components (calcium oxalate stones [COS]; non-calcium oxalate stones [NCOS]). Serum E2 (21.1 vs. 31.1 pg/ml) was significantly lower in kidney stones patients compared to controls. Post-hoc analysis demonstrated that this effect was driven by COS patients (p<0.001). According to tertiles of the E2 levels, a significant higher frequency of COS was seen in the lowest E2 group (p <0.001). Multiple logistic regression analysis identified E2 level as a strong factor that was independently associated with the risk for COS (per 1 SD increase, OR=0.951, 95% confidence interval [CI] = 0.919-0.985; highest: lowest tertile, OR=0.214, 95%CI = 0.069-0.665). However, serum T levels did not significantly differ among the groups. Naturally postmenopausal women with higher remaining estradiol levels appear less likely to suffer from kidney calcium oxalate stones. However, no correlation was found between serum T level and kidney stones. These findings support the hypothesis that higher postmenopausal endogenous estrogens may protect against kidney stones with ageing.

Size-dependent cellular uptake mechanism and cytotoxicity toward calcium oxalate on Vero cells

NASA Astrophysics Data System (ADS)

Sun, Xin-Yuan; Gan, Qiong-Zhi; Ouyang, Jian-Ming

2017-02-01

Urinary crystals with various sizes are present in healthy individuals and patients with kidney stone; however, the cellular uptake mechanism of calcium oxalate of various sizes has not been elucidated. This study aims to compare the internalization of nano-/micron-sized (50 nm, 100 nm, and 1 μm) calcium oxalate monohydrate (COM) and dihydrate (COD) crystals in African green monkey renal epithelial (Vero) cells. The internalization and adhesion of COM and COD crystals to Vero cells were enhanced with decreasing crystal size. Cell death rate was positively related to the amount of adhered and internalized crystals and exhibited higher correlation with internalization than that with adhesion. Vero cells mainly internalized nano-sized COM and COD crystals through clathrin-mediated pathways as well as micron-sized crystals through macropinocytosis. The internalized COM and COD crystals were distributed in the lysosomes and destroyed lysosomal integrity to some extent. The results of this study indicated that the size of crystal affected cellular uptake mechanism, and may provide an enlightenment for finding potential inhibitors of crystal uptake, thereby decreasing cell injury and the occurrence of kidney stones.

Mimicking the biomolecular control of calcium oxalate monohydrate crystal growth: effect of contiguous glutamic acids.

PubMed

Grohe, Bernd; Hug, Susanna; Langdon, Aaron; Jalkanen, Jari; Rogers, Kem A; Goldberg, Harvey A; Karttunen, Mikko; Hunter, Graeme K

2012-08-21

Scanning confocal interference microscopy (SCIM) and molecular dynamics (MD) simulations were used to investigate the adsorption of the synthetic polypeptide poly(l-glutamic acid) (poly-glu) to calcium oxalate monohydrate (COM) crystals and its effect on COM formation. At low concentrations (1 μg/mL), poly-glu inhibits growth most effectively in ⟨001⟩ directions, indicating strong interactions of the polypeptide with {121} crystal faces. Growth in <010> directions was inhibited only marginally by 1 μg/mL poly-glu, while growth in <100> directions did not appear to be affected. This suggests that, at low concentrations, poly-glu inhibits lattice-ion addition to the faces of COM in the order {121} > {010} ≥ {100}. At high concentrations (6 μg/mL), poly-glu resulted in the formation of dumbbell-shaped crystals featuring concave troughs on the {100} faces. The effects on crystal growth indicate that, at high concentrations, poly-glu interacts with the faces of COM in the order {100} > {121} > {010}. This mirrors MD simulations, which predicted that poly-glu will adsorb to a {100} terrace plane (most calcium-rich) in preference to a {121} (oblique) riser plane but will adsorb to {121} riser plane in preference to an {010} terrace plane (least calcium-rich). The effects of different poly-glu concentration on COM growth (1-6 μg/mL) may be due to variations between the faces in terms of growth mechanism and/or (nano)roughness, which can affect surface energy. In addition, 1 μg/mL might not be adequate to reach the critical concentration for poly-glu to significantly pin step movement on {100} and {010} faces. Understanding the mechanisms involved in these processes is essential for the development of agents to reduce recurrence of kidney stone disease.

Oxalate and phytate of soy foods.

PubMed

Al-Wahsh, Ismail A; Horner, Harry T; Palmer, Reid G; Reddy, Manju B; Massey, Linda K

2005-07-13

The consumption of foods made from soybeans is increasing because of their desirable nutritional value. However, some soy foods contain high concentrations of oxalate and/or phytate. Oxalate is a component of calcium oxalate kidney stones, whereas phytate is an inhibitor of calcium kidney stone formation. Thirty tested commercial soy foods exhibited ranges of 0.02-2.06 mg oxalate/g and 0.80-18.79 mg phytate/g. Commercial soy foods contained 2-58 mg of total oxalate per serving and 76-528 mg phytate per serving. Eighteen of 19 tofu brands and two soymilk brands contained less than 10 mg oxalate per serving, defined as a low oxalate food. Soy flour, textured vegetable soy protein, vegetable soybeans, soy nuts, tempeh, and soynut butter exhibited greater than 10 mg per serving. The correlation between oxalate and phytate in the soy foods was significant (r = 0.71, P < 0.001) indicating that oxalate-rich soy foods also contain higher concentrations of phytate. There also was a significant correlation, based on molar basis, between the divalent ion binding potential of oxalate plus phytate and calcium plus magnesium (r = 0.90, P < 0.001) in soy foods. Soy foods containing small concentrations of oxalate and moderate concentrations of phytate may be advantageous for kidney stone patients or persons with a high risk of kidney stones.

Computerized tomography magnified bone windows are superior to standard soft tissue windows for accurate measurement of stone size: an in vitro and clinical study.

PubMed

Eisner, Brian H; Kambadakone, Avinash; Monga, Manoj; Anderson, James K; Thoreson, Andrew A; Lee, Hang; Dretler, Stephen P; Sahani, Dushyant V

2009-04-01

We determined the most accurate method of measuring urinary stones on computerized tomography. For the in vitro portion of the study 24 calculi, including 12 calcium oxalate monohydrate and 12 uric acid stones, that had been previously collected at our clinic were measured manually with hand calipers as the gold standard measurement. The calculi were then embedded into human kidney-sized potatoes and scanned using 64-slice multidetector computerized tomography. Computerized tomography measurements were performed at 4 window settings, including standard soft tissue windows (window width-320 and window length-50), standard bone windows (window width-1120 and window length-300), 5.13x magnified soft tissue windows and 5.13x magnified bone windows. Maximum stone dimensions were recorded. For the in vivo portion of the study 41 patients with distal ureteral stones who underwent noncontrast computerized tomography and subsequently spontaneously passed the stones were analyzed. All analyzed stones were 100% calcium oxalate monohydrate or mixed, calcium based stones. Stones were prospectively collected at the clinic and the largest diameter was measured with digital calipers as the gold standard. This was compared to computerized tomography measurements using 4.0x magnified soft tissue windows and 4.0x magnified bone windows. Statistical comparisons were performed using Pearson's correlation and paired t test. In the in vitro portion of the study the most accurate measurements were obtained using 5.13x magnified bone windows with a mean 0.13 mm difference from caliper measurement (p = 0.6). Measurements performed in the soft tissue window with and without magnification, and in the bone window without magnification were significantly different from hand caliper measurements (mean difference 1.2, 1.9 and 1.4 mm, p = 0.003, <0.001 and 0.0002, respectively). When comparing measurement errors between stones of different composition in vitro, the error for calcium oxalate

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 (λ = 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 (λ = 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-μs, and pulse rates of 10-500 Hz was coupled into 100-μm-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.

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

PubMed

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

2010-12-01

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.

Kidney stones during pregnancy: an investigation into stone composition.

PubMed

Ross, Ashley E; Handa, Shelly; Lingeman, James E; Matlaga, Brian R

2008-05-01

Kidney stones can be a source of considerable morbidity for pregnant women. Although there is a body of literature confirming that different stone compositions predominate for different age and sex cohorts, there have been no similar reports characterizing the nature of stone disease during pregnancy. We performed a multi-institutional study to define the composition of renal calculi diagnosed during pregnancy. We retrospectively reviewed the records from two stone referral centers of all patients diagnosed with a de novo kidney stone during pregnancy who underwent a procedure for the purpose of stone removal from June 2001 through September 2007. A total of 27 patients were identified, with a mean age of 26.8 years (range, 21-34). Twenty patients (74%) had no history of prior stone formation. Seven patients (26%) had previously formed stones, although none of these patients had a known kidney stone at the time they became pregnant. Stones were removed in the first, second, third trimester and immediately post-partum in 4, 52, 22, and 22% respectively. Stone removal was performed without complication in all cases. Analysis found that in 74% of all cases (20 patients) stones were composed predominantly of calcium phosphate (hydroxyapatite). In 26% of cases, (7 patients) the stones were composed predominantly of calcium oxalate. Of the seven patients with prior stone history, three patients had previously formed calcium phosphate stones and four patients had previously formed calcium oxalate stones. Calcium oxalate calculi are the most common stone in non-pregnant women of a comparable age as our subjects. However, our present data suggest that stones detected during pregnancy are most commonly composed of calcium phosphate (hydroxyapatite). Indeed, it is the minority of stones that are composed of calcium oxalate. Although the reason for this unusual preponderance of calcium phosphate calculi is unclear, physiologic alterations that occur during pregnancy may be

Correlation between the development of calcium oxalate stones and polymorphisms in the fibronectin gene in the Uighur population of the Xinjiang region of China.

PubMed

Murat, M; Aekeper, A; Yuan, L Y; Alim, T; Du, G J; Abdusamat, A; Wu, G W; Aniwer, Y

2015-10-29

Here, we have investigated the correlation between calcium oxalate stone formation and Fn gene polymorphisms in urinary calculi patients among the Uighur population (Xinjiang region). In this case control study, genomic DNA extracted from the peripheral blood of 129 patients with calcium oxalate stones (patient group) and 94 normal people (control group) was used to genotype polymorphisms in the rs6725958, rs10202709, and rs35343655 sites of the Fn gene by polymerase chain reaction-restriction fragment length polymorphism. Subsequently, the association between different genotypes and susceptibility to calcium oxalate stone formation was compared among the patient and control groups. Single nucleotide polymorphisms (SNPs) were detected in the rs6725958, rs10202709, and rs35343655 sites of the Fn gene among the patient and control groups. The genotype distributions of the three loci complied with the Hardy-Weinberg equilibrium. The results of allele frequencies of the patient/control group for polymorphisms in the rs6725958 site of the Fn gene were C = 179 (69.92%)/119 (63.30%) and A = 77 (30.08%)/69 (36.70%), in the rs10202709 site were C = 245 (95.70%)/176 (93.63%) and T = 11 (4.30%)/12 (6.38%), and in the rs35343655 site of the Fn gene were A = 139 (54.30%)/87 (46.28%) and G = 117 (45.70%)/101 (53.72%). We observed no significant differences between the three SNPs and development of calcium oxalate stones. Polymorphisms in rs6725958, rs10202709, and rs35343655 of the Fn gene had no obvious effect on the susceptibility to the development of calcium oxalate stones in the Uighur population, residing in the Xinjiang region of China.

Unusual calcium oxalate crystals in ethylene glycol poisoning.

PubMed

Godolphin, W; Meagher, E P; Sanders, H D; Frohlich, J

1980-06-01

A patient poisoned with ethylene glycol exhibited the symptoms of (1) hysteria, (2) metabolic acidosis with both a large anion gap and osmolal gap, and (3) crystalluria. However, the shape of the urinary crystals was prismatic and resembled hippurate rather than the expected dipyramidal calcium oxalate dihydrate. X-ray crystallography positively identified them as calcium oxalate monohydrate.

[Characteristics of encrustation of ureteric stents in patients with urinary stones].

PubMed

Bouzidi, H; Traxer, O; Doré, B; Amiel, J; Hadjadj, H; Conort, P; Daudon, M

2008-04-01

The goal of this prospective study was to characterize ureteral stents encrustation in stone formers. We report the results of a study based on 658 double-J stents (412 men and 246 women) collected from patients with in situ urinary calculi. The mean age was 48.2+/-16.0 years without differences between genders. Ureteral stent encrustation was analysed by infrared spectroscopy. Results are expressed according to the main component. The mean indwelling time was 73.5+/-73.2 days. The main component in stent encrustations was calcium oxalate (43.8%), essentially the monohydrate form (27.1%), followed by proteins (27.4%), calcium phosphates (16.4% with 8.4% brushite), and uric acid (5.2%). Struvite, detected on 49 stents, was the main component in 2.4% of cases. Significant differences according to gender and age were found: calcium oxalate monohydrate, which represented 24.5% in 20 to 29 years old men class increased to 37.0% in 50 to 59 years class and then decreased in older patients. Calcium oxalate dihydrate increased with age up to 70 years in women while it felt dramatically in man beyond 50 years old. Brushite was more abundant in young men (20.4% in patients aged 20-29 years) and was decreasing beyond this age while it remained in stable proportion for all age classes in women. Increasing prevalence of uric acid encrustations with age was observed, especially in men beyond the age of 70 years. Mineral encrustations increased with the indwelling time, the part of mineral being preponderant after 15 days: 7,3% of the stents had become massively encrusted within 113 days mean period. The comparison between biomaterials showed that silicone stents were significantly less encrusted than polyurethane stents. Stent encrustation constitutes a serious complication of ureteral stent use in stone formers. Lithogenic factors should be considered for the prevention of stent encrustation in these patients.

Biomineralogy of human urinary calculi (kidney stones) from some geographic regions of Sri Lanka.

PubMed

Chandrajith, Rohana; Wijewardana, Geethika; Dissanayake, C B; Abeygunasekara, Anurudha

2006-08-01

Kidney stones (urinary calculi) have become a global scourge since it has been recognized as one of the most painful medical problems. Primary causative factors for the formation of these stones are not clearly understood, though they are suspected to have a direct relationship to the composition of urine, which is mainly governed by diet and drinking water. Sixty nine urinary calculi samples which were collected from stone removal surgeries were analyzed chemically for their Na, K, Ca, Mg, Cu, Zn, Pb, Fe and phosphate contents. Structural and mineralogical properties of stones were studied by XRD and FT-IR methods. The mean contents of trace elements were 1348 mg kg(-1) (Na); 294 mg kg(-1) (K); 32% (Ca); 1426 mg kg(-1) (Mg); 8.39 mg kg(-1) (Mn); 258 mg kg(-1) (Fe); 67 mg kg(-1) (Cu); 675 mg kg(-1) (Zn); 69 mg kg(-1) (Pb); and 1.93% (PO (4) (3-) ). The major crystalline constituent in the calculi of Sri Lanka is calcium oxalate monohydrate. Principal component analysis was used to identify the multi element relationships in kidney stones. Three components were extracted and the first component represents positively correlated Na-K-Mg-PO (4) (3-) whereas the second components represent the larger positively weighted Fe-Cu-Pb. Ca-Zn correlated positively in the third component in which Mn-Cu correlated negatively. This study indicates that during the crystallization of human urinary stones, Ca shows more affinity towards oxalates whereas other alkali and alkaline earths precipitate with phosphates.

[Changes in kidney stones type according to sex and age in Tunisian patients].

PubMed

Alaya, A; Nouri, A; Belgith, M; Saad, H; Hell, I; Hellara, W; Jouini, R; Najjar, M F

2012-03-01

Studies that evaluate the effect of age and gender on the stone composition are scarce. The aim of this study is to highlight the modification of epidemiological characteristics of this pathology according to patients' sex and age. We studied 1269 urolithiasic patients ranging from 6 months to 92 years old and known as having urinary stones (752 males and 517 females). Stone analysis was performed respectively using a stereomicroscope and infrared spectroscopy to determine, respectively, the morphological type and molecular composition of each. The annual average incidence of new stone formation was 30.25 per 100,000 inhabitants. In 1041 patients (81%), calculi were located in the upper urinary tract. Children and old man were more affected by bladder stone. Calcium oxalate monohydrate remains the most frequent stone component even if its frequency fell according to age (63.2% in teenagers and 40.6% in elderly [p<0.05]) in favour of the increase of uric acid stones (3,5% in teenagers and 41.5% in elderly [p<0.05]). Struvite stones were rare (3.5%) and more frequent in children. The analysis of these data shows that urinary stones in Tunisia are tending to evolve in the same direction as in industrialized countries. Copyright © 2011 AEU. Published by Elsevier Espana. All rights reserved.

Gas-containing renal stones: findings from five consecutive patients.

PubMed

Manny, Ted B; Mufarrij, Patrick W; Lange, Jessica N; Mirzazadeh, Majid; Hemal, Ashok K; Assimos, Dean G

2012-12-01

To describe the clinical course, microbiology, and metabolic findings of 5 patients presenting to our institution with gas-containing renal stones. During a 20-month period beginning in 2009, 5 patients were identified by computed tomography scanning to harbor gas-containing renal calculi. Despite similar imaging and referral practice patterns, no such cases had been seen at our institution in the preceding 20 years. The records of these patients were reviewed to better characterize this unique condition. All 5 subjects were premenopausal women. One patient presented with urosepsis and 4 presented with flank pain. All had urinary tract infections, and Escherichia coli was isolated from a voided urine specimen in 3. Stone culture was positive in 2 and was concordant with the voided specimen in 1. The stones were solitary in 4 and multiple in 1 patient. All the stones were composed of calcium phosphate. Of the 5 patients, 3 had pure calcium phosphate stones and 2 had stones with calcium oxalate monohydrate components. Also, 3 subjects had diabetes mellitus, 3 had hypertension, and 1 had a history of gout. Two subjects underwent 24-hour urine metabolic testing, and abnormalities were identified in both. All patients were rendered stone free: 4 with percutaneous nephrostolithotomy and 1 using robotic pyelolithotomy. Gas-containing renal stones are rare but might be increasing in prevalence. The pathophysiology is unknown but is most likely influenced by a combination of metabolic and infectious factors. Copyright © 2012 Elsevier Inc. All rights reserved.

Phase transformation of calcium oxalate dihydrate-monohydrate: Effects of relative humidity and new spectroscopic data

NASA Astrophysics Data System (ADS)

Conti, Claudia; Casati, Marco; Colombo, Chiara; Realini, Marco; Brambilla, Luigi; Zerbi, Giuseppe

2014-07-01

New data on vibrational properties of calcium oxalates and their controversial transformation mechanism are presented. We have focused on whewellite (CaC2O4·H2O) and weddellite [CaC2O4·(2 + x) H2O], the most common phases of calcium oxalate; these compounds occur in many organisms, in kidney stones and in particular kinds of films found on the surface of many works of art. Low temperature experiments carried out by Fourier transform infrared spectroscopy have highlighted both the high structural order in the crystalline state of whewellite and the disordered distribution of the zeolitic water molecules in weddellite. The synthesised nanocrystals of weddellite have been kept under different hygrometric conditions in order to study, by X-ray powder diffraction, the role of “external” water molecules on their stability. Moreover, in order to identify the different kinds of water molecules, a re-investigation, supported by quantum chemical calculations, of the observed vibrational spectra (IR and Raman) of whewellite has been conducted.

Synthesis of glycoside derivatives of hydroxyanthraquinone with ability to dissolve and inhibit formation of crystals of calcium oxalate. Potential compounds in kidney stone therapy.

PubMed

Frackowiak, Anna; Skibiński, Przemysław; Gaweł, Wiesław; Zaczyńska, Ewa; Czarny, Anna; Gancarz, Roman

2010-03-01

Synthesis of glycosyl derivatives of hydroxyanthraquinones (6-10) potentially useful for kidney stone therapy is presented. These compounds were analyzed as inhibitors of calcium oxalate crystals formation as well as substances with the ability of dissolving crystalline calcium oxalate. In addition, the effect of the compounds obtained on real kidney stones was analyzed by ex vivo tests. The tests on L929 and A545 cell lines have shown that the compounds obtained were not cytotoxic. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.

Changes in urinary stone composition in the Tunisian population: a retrospective study of 1,301 cases.

PubMed

Alaya, Akram; Nouri, Abdellatif; Belgith, Mohsen; Saad, Hammadi; Jouini, Riadh; Najjar, Mohamed Fadhel

2012-05-01

Studies that evaluate the effect of age on stone composition are scarce. The aim of this study was to highlight the changes in epidemiological characteristics (stone composition and location) of urolithiasis according to patients' age. We studied 1,301 urolithiasis patients with age ranging from 6 months to 92 yr (781 males and 520 females). Stone analysis was performed using a stereomicroscope and infrared spectroscopy to determine the morphological type and molecular composition of each stone. The annual average incidence of new stone formation was 31.7 per 100,000 persons. In 71.8% of cases, calculi were located in the upper urinary tract. Compared to other age groups, children and old men were more affected by bladder stones. Calcium oxalate monohydrate was the most frequent stone component, even though its frequency decreased with age (59.5% in young adults and 43.7% in the elderly, P<0.05) in favor of an increase in uric acid stones (11.5% in young adults and 36.4% in the elderly, P<0.05). Struvite stones were rare (3.8%) and more frequent in children than in adults. The analysis of these data showed that urinary stones in Tunisian patients are tending to evolve in the same direction as the stones in patients from industrialized countries.

Association Study of Klotho Gene Polymorphism With Calcium Oxalate Stones in The Uyghur Population of Xinjiang, China.

PubMed

Ali, Abdusamat; Tursun, Halmurat; Talat, Alim; Abla, Akpar; Muhtar, Erpan; Zhang, Tao; Mahmut, Murat

2017-01-18

The aim of the present study was to investigate the correlation between Klotho gene polymorphisms andcalcium oxalate stones in Xinjiang Uyghur people. We compared 128 patients with calcium oxalate stones (case group) and 94 healthypeople (control group), detected the genotype and allele distributions of single-nucleotide polymorphisms (SNPs)of the Klotho gene (rs3752472, rs650439, and rs1207568) by reverse transcription polymerase chain reaction. The distributions of the genotype and allele frequencies of the SNPs were consistent with the Hardy-Weinberg equilibrium in the two groups. There were statistically significant differences between the genotype andallele distributions of rs3752472 between the case and control groups; the allele frequencies in the case/controlgroups were C = 240 (93.7%)/151 (80.3%) and T = 16 (6.3%)/37 (19.7%). There was no statistically significantdifference in the genotype distribution of rs650439 between the case and control groups, but there was a differencein the allele distribution; the allele frequencies in the case/control groups were A = 202 (78.9%)/143 (57.2%) andT = 54 (21.1%)/107 (42.8%). There were no statistically significant differences in genotype and allele distributionsbetween the case and control groups of rs1207568; the allele frequencies in the case/control groups were C = 194(71.3%)/145 (77.1%) and T = 78 (28.7%)/43 (22.9%). In rs3752472, the risk for patients with the C and A allelesincreased by 3.675 and 2.799 times, respectively. The rs3752472 and rs650439 SNPs are related to the risk of calcium oxalate stones in Xinjiang Uyghurpeople, and might be one of the risk factors.

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.

Renal calcinosis and stone formation in mice lacking osteopontin, Tamm-Horsfall protein, or both.

PubMed

Mo, Lan; Liaw, Lucy; Evan, Andrew P; Sommer, Andre J; Lieske, John C; Wu, Xue-Ru

2007-12-01

Although often supersaturated with mineral salts such as calcium phosphate and calcium oxalate, normal urine possesses an innate ability to keep them from forming harmful crystals. This inhibitory activity has been attributed to the presence of urinary macromolecules, although controversies abound regarding their role, or lack thereof, in preventing renal mineralization. Here, we show that 10% of the mice lacking osteopontin (OPN) and 14.3% of the mice lacking Tamm-Horsfall protein (THP) spontaneously form interstitial deposits of calcium phosphate within the renal papillae, events never seen in wild-type mice. Lack of both proteins causes renal crystallization in 39.3% of the double-null mice. Urinalysis revealed elevated concentrations of urine phosphorus and brushite (calcium phosphate) supersaturation in THP-null and OPN/THP-double null mice, suggesting that impaired phosphorus handling may be linked to interstitial papillary calcinosis in THP- but not in OPN-null mice. In contrast, experimentally induced hyperoxaluria provokes widespread intratubular calcium oxalate crystallization and stone formation in OPN/THP-double null mice, while completely sparing the wild-type controls. Whole urine from OPN-, THP-, or double-null mice all possessed a dramatically reduced ability to inhibit the adhesion of calcium oxalate monohydrate crystals to renal epithelial cells. These data establish OPN and THP as powerful and functionally synergistic inhibitors of calcium phosphate and calcium oxalate crystallization in vivo and suggest that defects in either molecule may contribute to renal calcinosis and stone formation, an exceedingly common condition that afflicts up to 12% males and 5% females.

Combined Burst Wave Lithotripsy and Ultrasonic Propulsion for Improved Urinary Stone Fragmentation.

PubMed

Zwaschka, Theresa A; Ahn, Justin S; Cunitz, Bryan W; Bailey, Michael R; Dunmire, Barbrina; Sorensen, Mathew D; Harper, Jonathan D; Maxwell, Adam D

2018-04-01

Burst wave lithotripsy (BWL) is a new technology in development to fragment urinary stones. Ultrasonic propulsion (UP) is a separate technology under investigation for displacing stones. We measure the effect of propulsion pulses on stone fragmentation from BWL. Two artificial stone models (crystalline calcite, BegoStone plaster) and human calcium oxalate monohydrate (COM) stones measuring 5 to 8 mm were subjected to ultrasound exposures in a polyvinyl chloride tissue phantom within a water bath. Stones were exposed to BWL with and without propulsion pulses interleaved for set time intervals depending on stone type. Fragmentation was measured as a fraction of the initial stone mass fragmented to pieces smaller than 2 mm. BegoStone model comminution improved from 6% to 35% (p < 0.001) between BWL and BWL with interleaved propulsion in a 10-minute exposure. Propulsion alone did not fragment stones, whereas addition of propulsion after BWL slightly improved BegoStone model comminution from 6% to 11% (p < 0.001). BegoStone model fragmentation increased with rate of propulsion pulses. Calcite stone fragmentation improved from 24% to 39% in 5 minutes (p = 0.047) and COM stones improved from 17% to 36% (p = 0.01) with interleaved propulsion. BWL with UP improved stone fragmentation compared with BWL alone in vitro. The improvement was greatest when propulsion pulses are interleaved with BWL treatment and when propulsion pulses are applied at a higher rate. Thus, UP may be a useful adjunct to enhance fragmentation in lithotripsy in vivo.

The usefulness of densitometry in predicting the composition and fragility of urolithiasis.

PubMed

Argüelles-Salido, Enrique; Lozano-Blasco, Jose Maria; Subira-Rios, Jorge; Bernardo-Villar, Pastora; Podio-Lora, Virtudes; Campoy-Martínez, Pedro; Vazquez-Albertino, Ricardo; Medina-Lopez, Rafael

2014-04-01

The choice of ideal treatment for a given lithiasis is a crucial factor for its success, minimizing the number of interventions and complications. Previous determination of stone composition and its fragility is desirable, to predict its behavior during extracorporeal shock wave lithotripsy and for evaluation of its appropriateness, or to set the indication for other techniques. To determine the role of densitometry in the prediction of composition and fragility of urinary lithiasis undergoing SWL. Experimental prospective, blinded, in vitro study using 193 urinary calculi of known composition : monohydrated calcium oxalate, mixed calcium oxalate, uric acid, and calcium carbonate, obtained from spontaneous passage or surgery. Densitometry and SWL were performed on them. We compare the mineral composition of the stone and mineral density of each composition group to check if they are characteristic of each type and correlate these parameters with the energy dose required to fragment them down to a given fragment size. Only 53 out of 193 stones showed valuable data. Calcium carbonate was the composition showing grater mineral content and density (1,24 gr and 0,47 gr/cm2), followed by mixed oxalate (0,51/0,26) and uric acid (0,52/ 0,15), finishing with the monohydrate calcium oxalate group (0,32/0,05).Only the comparison between calcium carbonate and monohydrated calcium oxalate showed statistically significant results (p<0,05). Correlation coefficients between mineral content (0,347) and density (0,424) and the energy used for stone fragmentation to a given fragment size were statistically significant (p<0,05) CONCLUSIONS: In our study, the use of densitometry to determine stone composition and lithiasic fragility did not show conclusive results due to the limited number of calculi tested. Nevertheless, there are signs that, with a different study design , more practically useful results could be achieved.

Impact of Dietary Calcium and Oxalate, and Oxalobacter Formigenes Colonization on Urinary Oxalate Excretion

PubMed Central

Jiang, Juquan; Knight, John; Easter, Linda H.; Neiberg, Rebecca; Holmes, Ross P.; Assimos, Dean G.

2011-01-01

Purpose Enteric colonization with Oxalobacter formigenes, a bacterium whose main energy source is oxalate, has been demonstrated to decrease the risk of recurrent calcium oxalate kidney stone formation. We assessed the impact of diets controlled in calcium and oxalate contents on urinary and fecal analytes in healthy subjects who were naturally colonized with O. formigenes or not colonized with O. formigenes. Materials and Methods A total of 11 O. formigenes colonized and 11 noncolonized subjects were administered diets controlled in calcium and oxalate contents. We assayed 24-hour urine collections and stool samples obtained on the last 4 days of each 1-week diet for stone risk parameters and O. formigenes levels. Mixed model analysis was used to determine the effects of colonization status on these variables. Results Urinary calcium and oxalate excretion were significantly altered by the dietary changes in O. formigenes colonized and noncolonized individuals. Mixed model analysis showed significant interaction between colonization status and oxalate excretion on a low calcium (400 mg daily)/moderate oxalate (250 mg daily) diet (p = 0.026). Urinary oxalate excretion was 19.5% lower in O. formigenes colonized subjects than in noncolonized subjects on the low calcium/moderate oxalate diet (mean ± SE 34.9 ± 2.6 vs 43.6 ± 2.6 mg, p = 0.031). Conclusions Results suggest that O. formigenes colonization decreases oxalate excretion during periods of low calcium and moderate oxalate intake. PMID:21575973

The role of intestinal oxalate transport in hyperoxaluria and the formation of kidney stones in animals and man

PubMed Central

Whittamore, Jonathan M.; Hatch, Marguerite

2016-01-01

The intestine exerts a considerable influence over urinary oxalate in two ways, through the absorption of dietary oxalate and by serving as an adaptive extra-renal pathway for elimination of this waste metabolite. Knowledge of the mechanisms responsible for oxalate absorption and secretion by the intestine therefore have significant implications for understanding the etiology of hyperoxaluria, as well as offering potential targets for future treatment strategies for calcium oxalate kidney stone disease. In this review, we present the recent developments and advances in this area over the past 10 years, and put to the test some of the new ideas that have emerged during this time, using human and mouse models. A key focus for our discussion are the membrane-bound anion exchangers, belonging to the SLC26 gene family, some of which have been shown to participate in transcellular oxalate absorption and secretion. This has offered the opportunity to not only examine the roles of these specific transporters, revealing their importance to oxalate homeostasis, but to also probe the relative contributions made by the active transcellular and passive paracellular components of oxalate transport across the intestine. We also discuss some of the various physiological stimuli and signaling pathways which have been suggested to participate in the adaptation and regulation of intestinal oxalate transport. Finally, we offer an update on research into Oxalobacter formigenes, alongside recent investigations of other oxalate-degrading gut bacteria, in both laboratory animals and humans. PMID:27913853

Flow-driven pattern formation in the calcium-oxalate system.

PubMed

Bohner, Bíborka; Endrődi, Balázs; Horváth, Dezső; Tóth, Ágota

2016-04-28

The precipitation reaction of calcium oxalate is studied experimentally in the presence of spatial gradients by controlled flow of calcium into oxalate solution. The density difference between the reactants leads to strong convection in the form of a gravity current that drives the spatiotemporal pattern formation. The phase diagram of the system is constructed, the evolving precipitate patterns are analyzed and quantitatively characterized by their diameters and the average height of the gravity flow. The compact structures of calcium oxalate monohydrate produced at low flow rates are replaced by the thermodynamically unstable calcium oxalate dihydrate favored in the presence of a strong gravity current.

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.

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

Human stones.

PubMed

Lonsdale, K

1968-03-15

X-ray diffraction studies have shown that there are several different kinds of human urinary calculi, with different age, sex, period, and geographical distributions. Juvenile bladder stones are typically urate and oxalate in small boys in certain stone belts. They have disappeared in some areas, particularly in Britain, but are still common in Thailand. India. and Turkey. Their cause is unknown. Adult bladder stones, formerly common in elderly men, were largely of uric acid and were due to a faulty diet. Juvenile kidney stones are rare, except in Turkey where they are similar to juvenile bladder stones. Adult kidney stones are by far the most universally common, especially in technically developed communities. They are found in both sexes (equally at postmortem), and in the United States and in Czechoslovakia the average number of hospital entries for stones, relative to the whole population, is about 1 per 1000 per annum (increasing) although the incidence in different districts varies by 4 to 1 or more. Such stones are mainly calcium oxalates and calcium and MgNH(4) phosphates. The incidence among the administrative class is at least 20 times that among agricultural workers, relative to their numbers. Stones are reported also to be an occupational hazard for air pilots. It is probably that much more exercise and the drinking of more water to prevent kidney dehydration (spirits and coffee are not effective for this purpose) would lower the high rate of incidence. Moderate acidification would prevent phosphate supersaturation of the urine, but is not effective for oxalates. It seems certain that, once a suitable seed is formed, epitaxy is largely responsible for deposition from urines that would otherwise remain supersaturated until voided. This would explain the curioLls radial and layered texture of many stones. Laboratory experiments might suggest ways of preventing orientated overgrowth.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, James C. Jr.; Zarse, Chad A.; Jackson, Molly 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 shownmore » 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.« less

[Infrared spectrophotometry for crystalline composition of staghorn calculi].

PubMed

Ma, Kai; Huang, Xiao-bo; Xu, Qing-quan; Li, Jian-xing; Xiong, Liu-lin; Yang, Bo; Ye, Xiong-jun; Chen, Liang; Wang, Xiao-feng; Na, Yan-qun

2010-11-30

To provide theoretic rationales for treatment and prevention of staghorn calculi by analyzing stone composition and studying the relationship between stone and urinary tract infections. The clinical data of 51 staghorn calculi patients were analyzed retrospectively. The stone compositions were studied by infrared spectrophotometry. Six types of stone compositions were obtained. There were calcium oxalate monohydrate, calcium oxalate dehydrate, carbonate apatite, magnesium ammonium phosphate hexahydrate, uric acid and L-cystine. The majority of stones were of mixed compositions, pure stones were found in 15 cases (29.4%). Among all stones, calcium oxalate stones were found in 41 cases (80.4%) and uric stones in 10 cases (19.6%). Infectious stones were found in 26 cases (51.0%). Urinary tract infections were found in 40 (78.4%) patients and positive urine/stone culture was detected in 33 (64.7%) patients. With multiple crystalline compositions and etiological factors, the staghorn calculi are closely correlated with urinary tract infections.

Kidney stones - self-care

MedlinePlus

... self-care; Nephrolithiasis and self-care; Stones and kidney - self-care; Calcium stones and self-care; Oxalate ... provider or the hospital because you have a kidney stone. You will need to take self-care ...

Successful treatment of sodium oxalate induced urolithiasis with Helichrysum flowers.

PubMed

Onaran, Metin; Orhan, Nilüfer; Farahvash, Amirali; Ekin, Hasya Nazlı; Kocabıyık, Murat; Gönül, İpek Işık; Şen, İlker; Aslan, Mustafa

2016-06-20

Helichrysum (Asteraceae) flowers, known as "altın otu, yayla çiçeği, kudama çiçeği" , are widely used to remove kidney stones and for their diuretic properties in Turkey. To determine the curative effect of infusions prepared from capitulums of Helichrysum graveolens (M. Bieb.) Sweet (HG) and H. stoechas ssp. barellieri (Ten.) Nyman (HS) on sodium oxalate induced kidney stones. Infusions prepared from the capitulums of HG and HS were tested for their curative effect on calcium oxalate deposition induced by sodium oxalate (70mg/kg i.p.). Following the injection of sodium oxalate for 5 days, plant extracts were administered to rats at two different doses. Potassium citrate was used as positive control. Water intake, urine volume, body, liver and kidney weights were measured; biochemical and hematological analyses were conducted on urine and blood samples. Additionally, histopathological examinations were done on kidney samples. H. stoechas extract showed prominent effect at 156mg/kg dose (stone formation score: 0.33), whereas number of kidney stones was maximum in sodium oxalate group (stone formation score: 2.33). The reduction in the uric acid and oxalate levels of urine samples and the elevation in the urine citrate levels are significant and promising in extract groups. Some hematological, biochemical and enzymatic markers are also ameliorated by the extracts. This is the first report on the curative effect of immortal flowers. Our preliminary study indicated that Helichrysum extracts may be used for treatment of urolithiasis and Helichrysum extracts are an alternative therapy to potassium citrate for patients suffering from kidney stones. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The use of chemical treatments for improved comminution of artificial stones.

PubMed

Heimbach, D; Kourambas, J; Zhong, P; Jacobs, J; Hesse, A; Mueller, S C; Delvecchio, F C; Cocks, F H; Preminger, G M

2004-05-01

The acoustic and mechanical properties of various stone compositions are significantly different and thus result in varying degrees of fragility. Consequently, results to shock wave lithotripsy (SWL) are influenced accordingly. We report the results of a study of fragility of various stone compositions, and the influence on each stone's baseline physical properties and fragility when exposed to various chemolytic solutions. Before SWL artificial stones of differing compositions were irrigated with various chemolytic solutions. Calcium oxalate monohydrate (COM) stones were treated with ethylenediaminetetraacetic acid (EDTA), stones composed of magnesium ammonium phosphate hydrogen were treated with hemiacidrin, and stones made of uric acid (UA) were treated with tromethamine. Synthetic urine served as a control for all stone groups. Using an ultrasound transmission technique, longitudinal wave propagation speed was measured in all groups of artificial stones. Stone density was also measured by using a pycnometer (based on Archimedes' principle). Based on these measurements transverse (shear) wave speed (assuming a constant Poisson's ratio), wave impedance and dynamic mechanical properties of the artificial stones were calculated. Moreover, the microhardness of these artificial stones was measured, and fragility testing using SWL with and without pretreatment with the previously mentioned chemolytic solutions, was performed. Wave speed, wave impedance, dynamic mechanical properties and microhardness of EDTA treated COM stones and tromethamine treated UA stones were found to decrease compared to untreated (synthetic urine) control groups. The suggestion that chemolytic pretreatment increases stone fragility was verified by the finding of increased stone comminution after SWL testing. Combining this medical pretreatment and SWL, the findings demonstrate a significant impact of various solvents on stone comminution, in particular EDTA treated COM stones, tromethamine

Poly[[diaqua­hemi-μ4-oxalato-μ2-oxalato-praseodymium(III)] monohydrate

PubMed Central

Yang, Ting-Hai; Chen, Qiang; Zhuang, Wei; Wang, Zhe; Yue, Bang-Yi

2009-01-01

In the title complex, {[Pr(C2O4)1.5(H2O)2]·H2O}n, the PrIII ion, which lies on a crystallographic inversion centre, is coordinated by seven O atoms from four oxalate ligands and two O atoms from two water ligands; further Pr—O coordination from tetra­dentate oxalate ligands forms a three-dimensional structure. The compound crystallized as a monohydrate, the water mol­ecule occupying space in small voids and being secured by O—H⋯O hydrogen bonding as an acceptor from ligand water H atoms and as a donor to oxalate O-acceptor sites. PMID:21577485

[May renal lithiasis be really prevented? New trends and therapeutic tools.

PubMed

Grases, Félix; Costa-Bauzá, Antonia; Prieto, Rafael M

2017-01-01

Renal calculi are generally formed as a result of the combination of certain factors, some related to urine composition (concentration of lithogenic substances, deficiency of crystallization inhibitors, presence of heterogeneous nucleants) and others with renal morphology and anatomy (urinary tract stasis, low urodynamic efficiency cavities, morpho-anatomic deformations, renal papillary tissue lesions). In fact, the composition, macrostructure and microstructure of the calculus will clearly depend on the factors that have induced it. For this reason, the appropriate study and classification of the renal calculi simplifies the diagnosis and allows a more effective therapeutic approach since it can be oriented to directly correct the etiological factors responsible for stone formation. In this article, we review the main etiological factors involved in the formation of each type of calculus and the prophylactic measures that can be adopted for proper correction. The most frequent kidney stones have been classified into the following types: calcium oxalate monohydrate papillary calculi, calcium oxalate monohydrate non-papillary calculi, calcium oxalate dihydrate calculi, mixed hydroxyapatite/ calcium oxalate calculi, carboxyapatite/hydroxyapatite calculi, brushite calculi, struvite/carboxyapatite calculi, uric acid calculi, uric acid/calcium oxalate monohydrate calculi, and cystine calculi. Occasionally, however, the calculus is not available for study, in which case the only way forward is to use all available information (clinical history, life habits, radiological data), together with basic biochemical information, to identify and correct all etiological factors related to renal lithiasis that have been identified.

Cooperation of phosphates and carboxylates controls calcium oxalate crystallization in ultrafiltered urine.

PubMed

Grohe, Bernd; Chan, Brian P H; Sørensen, Esben S; Lajoie, Gilles; Goldberg, Harvey A; Hunter, Graeme K

2011-10-01

Osteopontin (OPN) is one of a group of proteins found in urine that are believed to limit the formation of kidney stones. In the present study, we investigate the roles of phosphate and carboxylate groups in the OPN-mediated modulation of calcium oxalate (CaOx), the principal mineral phase found in kidney stones. To this end, crystallization was induced by addition of CaOx solution to ultrafiltered human urine containing either human kidney OPN (kOPN; 7 consecutive carboxylates, 8 phosphates) or synthesized peptides corresponding to residues 65-80 (pSHDHMDDDDDDDDDGD; pOPAR) or 220-235 (pSHEpSTEQSDAIDpSAEK; P3) of rat bone OPN. Sequence 65-80 was also synthesized without the phosphate group (OPAR). Effects on calcium oxalate monohydrate (COM) and dihydrate (COD) formation were studied by scanning electron microscopy. We found that controls form large, partly intergrown COM platelets; COD was never observed. Adding any of the polyelectrolytes was sufficient to prevent intergrowth of COM platelets entirely, inhibiting formation of these platelets strongly, and inducing formation of the COD phase. Strongest effects on COM formation were found for pOPAR and OPAR followed by kOPN and then P3, showing that acidity and hydrophilicity are crucial in polyelectrolyte-affected COM crystallization. At higher concentrations, OPAR also inhibited COD formation, while P3, kOPN and, in particular, pOPAR promoted COD, a difference explainable by the variations of carboxylate and phosphate groups present in the molecules. Thus, we conclude that carboxylate groups play a primary role in inhibiting COM formation, but phosphate and carboxylate groups are both important in initiating and promoting COD formation.

Isolation and characterizations of oxalate-binding proteins in the kidney

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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) tomore » 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

Chronic stress and calcium oxalate stone disease: influence on blood cortisol and urine composition.

PubMed

Arzoz-Fàbregas, Montserrat; Ibarz-Servio, Luis; Fernández-Castro, Jordi; Valiente-Malmagro, Manuel; Roca-Antonio, Josep; Edo-Izquierdo, Sílvia; Buisan-Rueda, Oscar

2013-12-01

To evaluate the influence of chronic stress (CS) on urine composition of calcium oxalate (CaOx) stone patients and controls. This case-control study enrolled 128 patients during a period of 20 months. The cases were CaOx stone formers with a recent stone episode. Controls were matched by sex and age. Dimensions of CS were evaluated in cases and controls by validated self-report questionnaires measuring stressful life events, perceived stress, anxiety, depression, burnout, and satisfaction with life. Blood and urine samples were collected to determine cortisol levels and urinary composition. More relations between CS dimensions and blood and urine parameters were observed in cases than in controls. In cases, the blood cortisol level was related positively with the number of stressful life events (P = .03), intensity of these events (P = .04), and anxiety (P = .04). In addition, urinary magnesium (P = .03) and pyrophosphate (P = .05) levels were positively related with satisfaction with life and burnout, respectively. In contrast, urinary magnesium levels were negatively related with perceived stress (P = .01), anxiety (P = .016), and depression (P = .03). In controls, the number of stressful life events and the intensity of stressful life events was related positively with magnesium (P = .06, P = .02) levels and negatively with blood cortisol levels (P = .03, P = .004). Based on the variation between cases and controls in relations between CS dimensions and biochemical parameters, we hypothesize that CS may trigger a differential biological response in CaOx stone formers and controls, which in turn may promote or protect against CaOx stone formation. Copyright © 2013 Elsevier Inc. All rights reserved.

Renal stone characterization using high resolution imaging mode on a photon counting detector CT system

NASA Astrophysics Data System (ADS)

Ferrero, A.; Gutjahr, R.; Henning, A.; Kappler, S.; Halaweish, A.; Abdurakhimova, D.; Peterson, Z.; Montoya, J.; Leng, S.; McCollough, C.

2017-03-01

In addition to the standard-resolution (SR) acquisition mode, a high-resolution (HR) mode is available on a research photon-counting-detector (PCD) whole-body CT system. In the HR mode each detector consists of a 2x2 array of 0.225 mm x 0.225 mm subpixel elements. This is in contrast to the SR mode that consists of a 4x4 array of the same subelements, and results in 0.25 mm isotropic resolution at iso-center for the HR mode. In this study, we quantified ex vivo the capabilities of the HR mode to characterize renal stones in terms of morphology and mineral composition. Forty pure stones - 10 uric acid (UA), 10 cystine (CYS), 10 calcium oxalate monohydrate (COM) and 10 apatite (APA) - and 14 mixed stones were placed in a 20 cm water phantom and scanned in HR mode, at radiation dose matched to that of routine dual-energy stone exams. Data from micro CT provided a reference for the quantification of morphology and mineral composition of the mixed stones. The area under the ROC curve was 1.0 for discriminating UA from CYS, 0.89 for CYS vs COM and 0.84 for COM vs APA. The root mean square error (RMSE) of the percent UA in mixed stones was 11.0% with a medium-sharp kernel and 15.6% with the sharpest kernel. The HR showed qualitatively accurate characterization of stone morphology relative to micro CT.

Renal Stone Characterization using High Resolution Imaging Mode on a Photon Counting Detector CT System.

PubMed

Ferrero, A; Gutjahr, R; Henning, A; Kappler, S; Halaweish, A; Abdurakhimova, D; Peterson, Z; Montoya, J; Leng, S; McCollough, C

2017-03-09

In addition to the standard-resolution (SR) acquisition mode, a high-resolution (HR) mode is available on a research photon-counting-detector (PCD) whole-body CT system. In the HR mode each detector consists of a 2x2 array of 0.225 mm × 0.225 mm subpixel elements. This is in contrast to the SR mode that consists of a 4x4 array of the same sub-elements, and results in 0.25 mm isotropic resolution at iso-center for the HR mode. In this study, we quantified ex vivo the capabilities of the HR mode to characterize renal stones in terms of morphology and mineral composition. Forty pure stones - 10 uric acid (UA), 10 cystine (CYS), 10 calcium oxalate monohydrate (COM) and 10 apatite (APA) - and 14 mixed stones were placed in a 20 cm water phantom and scanned in HR mode, at radiation dose matched to that of routine dual-energy stone exams. Data from micro CT provided a reference for the quantification of morphology and mineral composition of the mixed stones. The area under the ROC curve was 1.0 for discriminating UA from CYS, 0.89 for CYS vs COM and 0.84 for COM vs APA. The root mean square error (RMSE) of the percent UA in mixed stones was 11.0% with a medium-sharp kernel and 15.6% with the sharpest kernel. The HR showed qualitatively accurate characterization of stone morphology relative to micro CT.

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.

The effect of ascorbic acid ingestion on the biochemical and physicochemical risk factors associated with calcium oxalate kidney stone formation.

PubMed

Auer, B L; Auer, D; Rodgers, A L

1998-03-01

The present study was undertaken to determine the effect of ingestion of large doses of vitamin C on urinary oxalate excretion and on a number of other biochemical and physicochemical risk factors associated with calcium oxalate urolithiasis. A further objective was to determine urinary ascorbate excretion and to relate it qualitatively to ingested levels of the vitamin and oxalate excretion. Ten healthy males participated in a protocol in which 4 g ascorbic acid was ingested for 5 days. Urines (24 h) were collected prior to, during and after the protocol. The urine collection procedure was designed to allow for the analysis of oxalate in the presence and absence of an EDTA preservative and for the analysis of ascorbic acid by manual titration using 2,6 dichlorophenolindophenol. Physicochemical risk factors such as the calcium oxalate relative supersaturation and Tiselius risk index were calculated from urine composition. The results showed that erroneously high analytical oxalate levels occur in the asence of preservative. In the preserved samples there was no significant increase in oxalate excretion at any stage of the protocol. Ascorbate excretion increased when vitamin C ingestion commenced but levelled out after 24 hours suggesting that saturation of the metabolic pool is reached within 24 hours after which ingested ascorbic acid is excreted unmetabolized in the urine. While transient statistically significant changes occurred in some of the biochemical risk factors, they were not regarded as being clinically significant. There were no changes in either the calcium oxalate relative supersaturation or Tiselius risk index. It is concluded that ingestion of large doses of ascorbic acid does not affect the principal risk factors associated with calcium oxalate kidney stone formation.

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.

Crystallization of calcium oxalate monohydrate at dipalmitoylphosphatidylcholine monolayers in the presence of chondroitin sulfate A

NASA Astrophysics Data System (ADS)

Ouyang, Jian-Ming; Deng, Sui-Ping; Zhong, Jiu-Ping; Tieke, Bernd; Yu, Shu-Hong

2004-10-01

The growth and aggregation of calcium oxalate monohydrate (COM) crystals beneath dipalmitoylphosphatidylcholine (DPPC) monolayers in the presence of chondroitin sulfate A (C4S) was systematically examined under different surface pressure. The results indicated that the addition of C4S can inhibit the crystal growth and prevent the aggregation of COM crystals. Under a DPPC monolayer, well-defined three-dimensional hexagonal prisms and three-dimensional rhombus prisms with sharply angled tips were obtained. The DPPC monolayer at a surface pressure of 10 mN/m can match the Ca2+ distance of the (1 bar 0 1) face of COM better than at 20 mN/m. The addition of C4S could cooperatively modulate the interaction strength between the monolayer (or itself) with the specific morphology determining faces such as (1 bar 0 1) and (0 2 0), and thus results in remarkable stabilization of the (1 bar 0 1) faces. The dramatic changes in morphological details were due to the strong electrostatic interactions between the Ca2+-rich (1 bar 0 1) crystal faces of COM and the polyanionic polysaccharide C4S together with the negatively charged sites of the zwitterionic DPPC monolayers. The increase of the concentration of C4S can further enhance the stabilization of the (1 bar 0 1) face.

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.

Fasting urinary calcium-to-creatinine and oxalate-to-creatinine ratios in dogs with calcium oxalate urolithiasis and breed-matched controls.

PubMed

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

2015-01-01

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. 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. 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). 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. 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. 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. Copyright © 2015 by the American College of Veterinary Internal Medicine.

Fourier Transform Infrared Analysis of Urinary Calculi and Metabolic Studies in a Group of Sicilian Children.

PubMed

D'Alessandro, Maria Michela; Gennaro, Giuseppe; Tralongo, Pietro; Maringhini, Silvio

2017-05-01

Prevalence of urinary calculi in children has been increasing in the past years. We performed an analysis of the chemical composition of stones formers of the pediatric population in our geographical area over the years 2005 to 2013. Fourier transform infrared spectroscopy was employed for the determination of the calculus composition of a group of Sicilian children, and metabolic studies were performed to formulate the correct diagnosis and establish therapy. The prevalence of stone formation was much higher for boys than for girls, with a sex ratio of 1.9:1. The single most frequent component was found to be calcium oxalate monohydrate, and calcium oxalates (pure or mixed calculi) were the overall most frequent components. Calcium phosphates ranked 2nd for frequency, most often in mixed calculi, while urates ranked 3rd. The metabolic disorder most often associated with pure calcium oxalate monohydrate calculi was hypocitraturia, while hyperoxaluria was predominantly associated with calcium oxalate dihydrate calculi. Mixed calculi had the highest prevalence in our pediatric population. Our data showed that Fourier transform infrared spectroscopy was a useful tool for the determination of the calculi composition.

Scanning electron microscopy of real and artificial kidney stones before and after Thulium fiber laser ablation in air and water

NASA Astrophysics Data System (ADS)

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

2018-02-01

We investigated proposed mechanisms of laser lithotripsy, specifically for the novel, experimental Thulium fiber laser (TFL). Previous lithotripsy studies with the conventional Holmium:YAG laser noted a primary photothermal mechanism (vaporization). Our hypothesis is that an additional mechanical effect (fragmentation) occurs due to vaporization of water in stone material from high absorption of energy, called micro-explosions. The TFL irradiated calcium oxalate monohydrate (COM) and uric acid (UA) stones, as well as artificial stones (Ultracal30 and BegoStone), in air and water environments. TFL energy was varied to determine the relative effect on the ablation mechanism. Scanning electron microscopy (SEM) was used to study qualitative and characteristic changes in surface topography with correlation to presumed ablation mechanisms. Laser irradiation of stones in air produced charring and melting of the stone surface consistent with a photothermal effect and minimal fragmentation, suggesting no mechanical effect from micro-explosions. For COM stones ablated in water, there was prominent fragmentation in addition to recognized photothermal effects, supporting dual mechanisms during TFL lithotripsy. For UA stones, there were minimal photothermal effects, and dominant effects were mechanical. By increasing TFL pulse energy, a greater mechanical effect was demonstrated for both stone types. For artificial stones, there was no significant evidence of mechanical effects. TFL laser lithotripsy relies on two prominent mechanisms for stone ablation, photothermal and mechanical. Water is necessary for the mechanical effect which can be augmented by increasing pulse energy. Artificial stones may not provide a predictive model for mechanical effects during laser lithotripsy.

Growth and characterization of new semiorganic nonlinear optical and piezoelectric lithium sulfate monohydrate oxalate single crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadav, Harsh; Sinha, Nidhi; Kumar, Binay, E-mail: b3kumar69@yahoo.co.in

2015-04-15

Highlights: • A new semiorganic single crystal of LSO grown by slow evaporation technique. • Morphological studies of the LSO crystal deduced by BFDH law. • In the UV–vis spectrum wide transparent region and large band gap were found. • SHG is equal to KDP crystal and d{sub 33} was found to be equal to 6pC/N. • Grown crystal belongs to softer category. - Abstract: New semiorganic crystal of lithium sulfate monohydrate oxalate (LSO) for nonlinear application was synthesized by controlled slow evaporation method. The growth rate of various planes of the grown crystal was estimated by morphological study. Singlemore » crystal XRD analysis confirmed that the crystal belongs to triclinic lattice with space group P1. High transparency (∼95%) with large band gap (4.57 eV) was analyzed by UV–vis studies. FTIR and Raman spectroscopy were used to identify various functional groups present in the LSO crystal. SHG efficiency was found to be equal to the KDP crystal. Thermal stability (up to 117.54 °C) and melting point (242 °C) of the crystal were studied by TG-DTA. In dielectric measurements, the value of dielectric constant decreases with increase in frequency. Hardness studies confirmed soft nature of crystals. The piezoelectric coefficient was found to be 6pC/N along [0 0 1].« less

Microbiota Diversification and Crash Induced by Dietary Oxalate in the Mammalian Herbivore Neotoma albigula

PubMed Central

Dale, Colin; Dearing, M. Denise

2017-01-01

ABSTRACT Oxalate, broadly found in both dietary and endogenous sources, is a primary constituent in 80% of kidney stones, an affliction that has tripled in prevalence over the last 40 years. Oxalate-degrading bacteria within the gut microbiota can mitigate the effects of oxalate and are negatively correlated with kidney stone formation, but bacteriotherapies involving oxalate-degrading bacteria have met with mixed results. To inform the development of more effective and consistent bacteriotherapies, we sought to quantify the interactions and limits between oxalate and an oxalate-adapted microbiota from the wild mammalian herbivore Neotoma albigula (woodrat), which consumes a high-oxalate diet in the wild. We tracked the microbiota over a variable-oxalate diet ranging from 0.2% to 12%, with the upper limit approximating 10× the level of human consumption. The N. albigula microbiota was capable of degrading ~100% of dietary oxalate regardless of the amount consumed. However, the microbiota exhibited significant changes in diversity dynamically at the operational taxonomic unit (OTU), family, and community levels in accordance with oxalate input. Furthermore, a cohesive microbial network was stimulated by the consumption of oxalate and exhibited some resistance to the effects of prolonged exposure. This study demonstrates that the oxalate-adapted microbiota of N. albigula exhibits a very high level of degradation and tolerance for oxalate. IMPORTANCE The bacteria associated with mammalian hosts exhibit extensive interactions with overall host physiology and contribute significantly to the health of the host. Bacteria are vital to the mitigation of the toxic effects of oxalate specifically as mammals do not possess the enzymes to degrade this compound, which is present in the majority of kidney stones. Contrary to the body of literature on a few oxalate-degrading specialists, our work illustrates that oxalate stimulates a broad but cohesive microbial network in a

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.

Alpha-enolase on apical surface of renal tubular epithelial cells serves as a calcium oxalate crystal receptor

NASA Astrophysics Data System (ADS)

Fong-Ngern, Kedsarin; Thongboonkerd, Visith

2016-10-01

To search for a strategy to prevent kidney stone formation/recurrence, this study addressed the role of α-enolase on apical membrane of renal tubular cells in mediating calcium oxalate monohydrate (COM) crystal adhesion. Its presence on apical membrane and in COM crystal-bound fraction was confirmed by Western blotting and immunofluorescence staining. Pretreating MDCK cells with anti-α-enolase antibody, not isotype-controlled IgG, dramatically reduced cell-crystal adhesion. Immunofluorescence staining also confirmed the direct binding of purified α-enolase to COM crystals at {121} > {100} > {010} crystal faces. Coating COM crystals with urinary proteins diminished the crystal binding capacity to cells and purified α-enolase. Moreover, α-enolase selectively bound to COM, not other crystals. Chemico-protein interactions analysis revealed that α-enolase interacted directly with Ca2+ and Mg2+. Incubating the cells with Mg2+ prior to cell-crystal adhesion assay significantly reduced crystal binding on the cell surface, whereas preincubation with EDTA, a divalent cation chelator, completely abolished Mg2+ effect, indicating that COM and Mg2+ competitively bind to α-enolase. Taken together, we successfully confirmed the role of α-enolase as a COM crystal receptor to mediate COM crystal adhesion at apical membrane of renal tubular cells. It may also serve as a target for stone prevention by blocking cell-crystal adhesion and stone nidus formation.

Sat1 is dispensable for active oxalate secretion in mouse duodenum

PubMed Central

Ko, Narae; Knauf, Felix; Jiang, Zhirong; Markovich, Daniel

2012-01-01

Mice deficient for the apical membrane oxalate transporter SLC26A6 develop hyperoxalemia, hyperoxaluria, and calcium oxalate stones due to a defect in intestinal oxalate secretion. However, the nature of the basolateral membrane oxalate transport process that operates in series with SLC26A6 to mediate active oxalate secretion in the intestine remains unknown. Sulfate anion transporter-1 (Sat1 or SLC26A1) is a basolateral membrane anion exchanger that mediates intestinal oxalate transport. Moreover, Sat1-deficient mice also have a phenotype of hyperoxalemia, hyperoxaluria, and calcium oxalate stones. We, therefore, tested the role of Sat1 in mouse duodenum, a tissue with Sat1 expression and SLC26A6-dependent oxalate secretion. Although the active secretory flux of oxalate across mouse duodenum was strongly inhibited (>90%) by addition of the disulfonic stilbene DIDS to the basolateral solution, secretion was unaffected by changes in medium concentrations of sulfate and bicarbonate, key substrates for Sat1-mediated anion exchange. Inhibition of intracellular bicarbonate production by acetazolamide and complete removal of bicarbonate from the buffer also produced no change in oxalate secretion. Finally, active oxalate secretion was not reduced in Sat1-null mice. We conclude that a DIDS-sensitive basolateral transporter is involved in mediating oxalate secretion across mouse duodenum, but Sat1 itself is dispensable for this process. PMID:22517357

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.

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

Comparison of miniaturized percutaneous nephrolithotomy and flexible ureterorenoscopy for moderate size renal stones in elderly patients.

PubMed

Ozgor, Faruk; Yanaral, Fatih; Savun, Metin; Ozdemir, Harun; Caglar, Ufuk; Sarilar, Omer

2018-06-01

Life expectancy has become longer, thus the number of elderly people who require treatment for nephrolithiasis has increased. We aimed to analyze the efficacy of flexible ureterorenoscopy (f-URS) and miniaturized percutaneous nephrolithotomy (mPNL) in the management of 10 and 30 mm renal stones in patients aged >60 years. In prospective non-randomized series, the data of patients who underwent f-URS or mPNL for kidney stones between July 2013 and July 2016 were analyzed. The procedure was accepted as successful if the patient was achieved complete stone clearance according to CT imaging between 1-3 months postoperatively. In total 60 patients and 58 patients were underwent f-URS and mPNL, respectively. The mean operation time, fluoroscopy time and hospitalization time were significantly shorter for the f-URS (p < 0.001, p < 0.001, p < 0.001, respectively). According to Clavien classification system, complication rates were not significantly different between the groups (p = 0.673). The stone-free rate was 81.7% for the f-URS group and 77.6% for the mPNL group after a single-session procedure (p = 0.747). Calcium oxalate monohydrate stones were the most common stone type in both groups. In multivariate analysis, multiple stones localization was only independent factor to predict complications. Our study had showed that both f-URS and mPNL are effective treatment modalities for 10-30-mm renal stones in elderly patients. Additionally, presence of stones in multiple location was the only predictive factor for complication development. Copyright © 2017 Kaohsiung Medical University. Published by Elsevier Taiwan. All rights reserved.

Antiurolithiatic Potential of Neeri against Calcium-Oxalate Stones by Crystallization Inhibition, Free Radicals Scavenging, and NRK-52E Cell Protection from Oxalate Injury.

PubMed

Goyal, Parveen Kumar; Verma, Santosh Kumar; Sharma, Anil Kumar

2017-10-01

Neeri is a well-established polyherbal formulation prescribed for renal stones by the physicians but has not been experimentally evaluated for its antiurolithiatic potential using cell-lines. This study is aimed to scientifically substantiate the antiurolithiatic effect of Neeri extract (NRE) through calcium oxalate (CaOx) crystallization inhibition, scavenging of free radicals, and protection of renal tubular epithelial NRK-52E cells from oxalate-induced injury. The crystallization inhibition was studied by turbidimetric assay while the free radical scavenging potential was determined for superoxide and nitric oxide (NO) radicals. The cytoprotective effect against oxalate-induced injury was assessed by estimating lactate dehydrogenase (LDH) leakage and determining cell viability using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. NRE significantly inhibited the CaOx crystallization in a concentration-dependent manner and also scavenged superoxide (IC 50 302.88 μg/ml) and NO (IC 50 300.45 μg/ml) free radicals. It did not show any significant cytotoxicity for NRK-52E cells till the highest dose (500 μg/ml) and found to be safe. When NRK-52E cells, injured by exposing to oxalate crystals for 24 h, were treated with NRE, it appreciably prevented the cell injury in a dose-dependent manner. It significantly decreased the elevated LDH leakage toward normal range and improved renal cell viability (82.37% ± 0.87%), hence, prevented growth and retention of crystals. The experimental findings concluded that Neeri is a potent antiurolithiatic formulation that inhibited CaOx crystallization and prevented tubular retention of crystals by protecting the renal cells against oxalate-induced injury as well as reducing the oxidative stress by scavenging free radicals. Neeri extract significantly ( P < 0.001) inhibited the in vitro crystallization (88.11% ± 7.70%) of calcium oxalateIt reduced oxidative stress by scavenging superoxide and nitric oxide free

Differentiating Calcium Oxalate and Hydroxyapatite Stones In Vivo Using Dual-Energy CT and Urine Supersaturation and pH Values

PubMed Central

Liu, Yu; Qu, Mingliang; Carter, Rickey E.; Leng, Shuai; Ramirez-Giraldo, Juan Carlos; Jaramillo, Giselle; Krambeck, Amy E.; Lieske, John C.; Vrtiska, Terri J.; McCollough, Cynthia H.

2014-01-01

Rationale and Objectives Knowledge of urinary stone composition can guide therapeutic intervention for patients with calcium oxalate (CaOx) or hydroxyapatite (HA) stones. In this study, we determined the accuracy of noninvasive differentiation of these two stone types using dual-energy CT (DECT) and urine supersaturation (SS) and pH values. Materials and Methods Patients who underwent clinically indicated DECT scanning for stone disease and subsequent surgical intervention were enrolled. Stone composition was determined using infrared spectroscopy. DECT images were processed using custom-developed software that evaluated the ratio of CT numbers between low- and high-energy images. Clinical information, including patient age, gender, and urine pH and supersaturation profile, was obtained from electronic medical records. Simple and multiple logistic regressions were used to determine if the ratio of CT numbers could discriminate CaOx from HA stones alone or in conjunction with urine supersaturation and pH. Results Urinary stones (CaOx n = 43, HA n = 18) from 61 patients were included in this study. In a univariate model, DECT data, urine SS-HA, and urine pH had an area under the receiver operating characteristic curve of 0.78 (95% confidence interval [CI] 0.66–0.91, P = .016), 0.76 (95%CI 0.61–0.91, P = .003), and 0.60 (95% CI 0.44–0.75, P = .20), respectively, for predicting stone composition. The combination of CT data and the urinary SS-HA had an area under the receiver operating characteristic curve of 0.79 (95%CI 0.66–0.92, P = .007) for correctly differentiating these two stone types. Conclusions DECT differentiated between CaOx and HA stones similarly to SS-HA, whereas pH was a poor discriminator. The combination of DECT and urine SS or pH data did not improve this performance. PMID:24200478

MECHANISMS OF HUMAN KIDNEY STONE FORMATION

PubMed Central

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

2014-01-01

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 (ICSF) 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

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

Molecular modifiers reveal a mechanism of pathological crystal growth inhibition

NASA Astrophysics Data System (ADS)

Chung, Jihae; Granja, Ignacio; Taylor, Michael G.; Mpourmpakis, Giannis; Asplin, John R.; Rimer, Jeffrey D.

2016-08-01

Crystalline materials are crucial to the function of living organisms, in the shells of molluscs, the matrix of bone, the teeth of sea urchins, and the exoskeletons of coccoliths. However, pathological biomineralization can be an undesirable crystallization process associated with human diseases. The crystal growth of biogenic, natural and synthetic materials may be regulated by the action of modifiers, most commonly inhibitors, which range from small ions and molecules to large macromolecules. Inhibitors adsorb on crystal surfaces and impede the addition of solute, thereby reducing the rate of growth. Complex inhibitor-crystal interactions in biomineralization are often not well elucidated. Here we show that two molecular inhibitors of calcium oxalate monohydrate crystallization—citrate and hydroxycitrate—exhibit a mechanism that differs from classical theory in that inhibitor adsorption on crystal surfaces induces dissolution of the crystal under specific conditions rather than a reduced rate of crystal growth. This phenomenon occurs even in supersaturated solutions where inhibitor concentration is three orders of magnitude less than that of the solute. The results of bulk crystallization, in situ atomic force microscopy, and density functional theory studies are qualitatively consistent with a hypothesis that inhibitor-crystal interactions impart localized strain to the crystal lattice and that oxalate and calcium ions are released into solution to alleviate this strain. Calcium oxalate monohydrate is the principal component of human kidney stones and citrate is an often-used therapy, but hydroxycitrate is not. For hydroxycitrate to function as a kidney stone treatment, it must be excreted in urine. We report that hydroxycitrate ingested by non-stone-forming humans at an often-recommended dose leads to substantial urinary excretion. In vitro assays using human urine reveal that the molecular modifier hydroxycitrate is as effective an inhibitor of nucleation

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.

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

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

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

PubMed Central

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

2015-01-01

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

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

PubMed

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

2013-03-11

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. From the recently collected papillary calculi, we evaluated retrospectively patients, subjected to retrograde ureteroscopy, with COM papillary lithiasis. 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. 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.

Calcium Oxalate Urolithiasis: A Case of Missing Microbes?

PubMed

Batagello, Carlos Alfredo; Monga, Manoj; Miller, Aaron W

2018-05-29

Urinary stone disease (USD) has known associations with the gut microbiota. Approximately 80% of kidney stones contain oxalate as a primary constituent and diverse oxalate-degrading bacteria exist within the human gut that may protect against USD. While bacteriotherapy represents a promising strategy to eliminate oxalate and reduce the risk of USD, oxalate-degrading probiotics have had limited success. To identify limitations of oxalate-degrading probiotics and refine development of bacteriotherapies to prevent USD, we review the literature associated with the gut microbiota and USD. A literature search was performed to identify publications that examine the role of oxalate-degrading bacteria or the whole gut microbiota in oxalate metabolism and the pathophysiology of USD. We conducted a meta-analysis of studies that examined the association of the whole gut microbiota with USD. In addition, we evaluated the gut microbiota of healthy individuals and those with co-morbidities related to USD using publically available data from the American Gut Project (AGP). Studies on O. formigenes reveal that colonization by this species is not a good predictor of USD risk nor urinary oxalate excretion. The species of oxalate-degrading bacteria used in probiotics and duration of administration does not impact efficacy or persistence. Studies focused on the whole gut microbiota reveal broad shifts in the gut microbiota associated with USD and a diverse microbial network is associated with oxalate metabolism. AGP data analysis demonstrated a strong overlap in microbial genera depleted in diseased individuals among USD and co-morbidities. The associations between the gut microbiota and USD extend beyond individual functional microbial species. Common shifts in the gut microbiota may facilitate the onset of USD and/or co-morbidities. The successful development of bacteriotherapies to inhibit USD will need to incorporate strategies that target a broad diversity of bacteria rather than

Modulation of polyepoxysuccinic acid on crystallization of calcium oxalate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yanqing; Tang, Yongming, E-mail: tangym@njtech.edu.cn; Xu, Jinqiu

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 ofmore » PESA on CaOx crystal faces was confirmed. - Graphical abstract: Introduction of PESA into crystallization solutions promotes the formation of calcium oxalate dehydrate and modifies the morphology of crystals. - Highlights: • PESA induces the formation of COD at low supersaturation. • Establishment of Ca-rich surface augments the adsorption of PESA. • At Ca/Ox=0.5 PESA cannot induce the formation of COD compared with Ca/Ox=2. • Interaction of PESA with COM faces is stronger than that with COD faces.« less

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.

Concentration gradient of oxalate from cortex to papilla in rat kidney.

PubMed

Nakatani, Tatsuya; Ishii, Keiichi; Sugimoto, Toshikado; Kamikawa, Sadanori; Yamamoto, Keisuke; Yoneda, Yukio; Kanazawa, Toshinao; Kishimoto, Taketoshi

2003-02-01

The kidney eliminates the major fraction of plasma oxalate. It is well known that oxalate is freely filtered by glomeruli and secreted by the proximal tubules. However, the renal handling of oxalate in distal nephrons, which is considered as playing an important role in stone formation, remains obscure. At 15-180 min after intravenous injection of 14C-oxalate to rats, the intrarenal localization of radioactivity was quantitatively measured by the radioluminographic method using a bioimaging analyzer. Tissue radioactivity was compared with plasma, and urinary radioactivities were measured by a liquid scintillation counter. The control study was conducted with 14C-inulin. The radioactivity of 14C-oxalate in the papilla was 10 times greater than in the cortex and eight times greater than in the medulla 180 min after injection when almost no radioactivity was present in the urine. In contrast, the radioactivity of 14C-inulin was nine times less in the papilla than in the cortex at the same time. Oxalate remains in the renal papilla for an extended period. This accumulation of oxalate may be attributed to calcium oxalate crystal fixation along the deep nephron which is considered to be the first step of stone formation.

Dual energy CT kidney stone differentiation in photon counting computed tomography

NASA Astrophysics Data System (ADS)

Gutjahr, R.; Polster, C.; Henning, A.; Kappler, S.; Leng, S.; McCollough, C. H.; Sedlmair, M. U.; Schmidt, B.; Krauss, B.; Flohr, T. G.

2017-03-01

This study evaluates the capabilities of a whole-body photon counting CT system to differentiate between four common kidney stone materials, namely uric acid (UA), calcium oxalate monohydrate (COM), cystine (CYS), and apatite (APA) ex vivo. Two different x-ray spectra (120 kV and 140 kV) were applied and two acquisition modes were investigated. The macro-mode generates two energy threshold based image-volumes and two energy bin based image-volumes. In the chesspattern-mode four energy thresholds are applied. A virtual low energy image, as well as a virtual high energy image are derived from initial threshold-based images, while considering their statistically correlated nature. The energy bin based images of the macro-mode, as well as the virtual low and high energy image of the chesspattern-mode serve as input for our dual energy evaluation. The dual energy ratio of the individually segmented kidney stones were utilized to quantify the discriminability of the different materials. The dual energy ratios of the two acquisition modes showed high correlation for both applied spectra. Wilcoxon-rank sum tests and the evaluation of the area under the receiver operating characteristics curves suggest that the UA kidney stones are best differentiable from all other materials (AUC = 1.0), followed by CYS (AUC ≍ 0.9 compared against COM and APA). COM and APA, however, are hardly distinguishable (AUC between 0.63 and 0.76). The results hold true for the measurements of both spectra and both acquisition modes.

Effects of Orthosiphon grandiflorus, Hibiscus sabdariffa and Phyllanthus amarus extracts on risk factors for urinary calcium oxalate stones in rats.

PubMed

Woottisin, Surachet; Hossain, Rayhan Zubair; Yachantha, Chatchai; Sriboonlue, Pote; Ogawa, Yoshihide; Saito, Seiichi

2011-01-01

We evaluated the antilithic effect of Orthosiphon grandiflorus, Hibiscus sabdariffa and Phyllanthus amarus extracts on known risk factors for calcium oxalate stones in rats. We divided 30 male Wistar rats into 5 equal groups. Controls were fed a standard diet and the remaining groups received a 3% glycolate diet for 4 weeks to induce hyperoxaluria. One glycolate fed group served as the untreated group and the others were given oral extracts of Orthosiphon grandiflorus, Hibiscus sabdariffa or Phyllanthus amarus at a dose of 3.5 mg daily. We collected 24-hour urine and blood samples. Kidneys were harvested for histological examination. We measured the renal tissue content of calcium and oxalate. The Hibiscus sabdariffa group showed significantly decreased serum oxalate and glycolate, and higher oxalate urinary excretion. The Phyllanthus amarus group showed significantly increased urinary citrate vs the untreated group. Histological examination revealed less CaOx crystal deposition in the kidneys of Hibiscus sabdariffa and Phyllanthus amarus treated rats than in untreated rats. Those rats also had significantly lower renal tissue calcium content than untreated rats. All parameters in the Orthosiphon grandiflorus treated group were comparable to those in the untreated group. Hibiscus sabdariffa and Phyllanthus amarus decreased calcium crystal deposition in the kidneys. The antilithic effect of Hibiscus sabdariffa may be related to decreased oxalate retention in the kidney and more excretion into urine while that of Phyllanthus amarus may depend on increased urinary citrate. In contrast, administering Orthosiphon grandiflorus had no antilithic effect. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Characterization of calcium oxalate biominerals in some (non-Cactaceae) succulent plant species.

PubMed

Monje, Paula V; Baran, Enrique J

2010-01-01

The water-accumulating leaves of crassulacean acid metabolism plants belonging to five different families were investigated for the presence of biominerals by infrared spectroscopic and microscopic analyses. Spectroscopic results revealed that the mineral present in succulent species of Agavaceae, Aizoaceae, and Asphodelaceae was calcium oxalate monohydrate (whewellite, CaC2O4 x H2O). Crystals were predominantly found as raphides or solitary crystals of various morphologies. However, representative Crassulaceae members and a succulent species of Asteraceae did not show the presence of biominerals. Overall, these results suggest no correlation between calcium oxalate generation and crassulacean acid metabolism in succulent plants.

Prophylactic role of phycocyanin: a study of oxalate mediated renal cell injury.

PubMed

Farooq, Shukkur Muhammed; Asokan, Devarajan; Kalaiselvi, Periandavan; Sakthivel, Ramasamy; Varalakshmi, Palaninathan

2004-08-10

Oxalate induced renal calculi formation and the associated renal injury is thought to be caused by free radical mediated mechanisms. An in vivo model was used to investigate the effect of phycocyanin (from Spirulina platensis), a known antioxidant, against calcium oxalate urolithiasis. Male Wistar rats were divided into four groups. Hyperoxaluria was induced in two of these groups by intraperitoneal infusion of sodium oxalate (70 mg/kg) and a pretreatment of phycocyanin (100 mg/kg) as a single oral dosage was given, 1h prior to sodium oxalate infusion. An untreated control and drug control (phycocyanin alone) were also included in the study. We observed that phycocyanin significantly controlled the early biochemical changes in calcium oxalate stone formation. The antiurolithic nature of the drug was evaluated by the assessment of urinary risk factors and light microscopic observation of urinary crystals. Renal tubular damage as divulged by urinary marker enzymes (alkaline phosphatase, acid phosphatase and gamma-glutamyl transferase) and histopathological observations such as decreased tubulointerstitial, tubular dilatation and mononuclear inflammatory cells, indicated that renal damage was minimised in drug-pretreated group. Oxalate levels (P < 0.001) and lipid peroxidation (P < 0.001) in kidney tissue were significantly controlled by drug pretreatment, suggesting the ability of phycocyanin to quench the free radicals, thereby preventing the lipid peroxidation mediated tissue damage and oxalate entry. This accounts for the prevention of CaOx stones. Thus, the present analysis revealed the antioxidant and antiurolithic potential of phycocyanin thereby projecting it as a promising therapeutic agent against renal cell injury associated kidney stone formation.

Influence of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion.

PubMed

Thomas, E; von Unruh, G E; Hesse, A

2008-09-01

To compare quantitatively the effect of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion. Eight healthy volunteers (three men and five women, mean age 28.6+/-6.3) were studied. Each volunteer performed the [(13)C(2)]oxalate absorption test thrice on a low-oxalate mixed diet, thrice on a low-oxalate vegetarian diet and thrice on a high-oxalate vegetarian diet. For each test, the volunteers had to adhere to an identical diet and collect their 24-h urines. In the morning of the second day, a capsule containing [(13)C(2)]oxalate was ingested. On the low-oxalate vegetarian diet, mean intestinal oxalate absorption and urinary oxalate excretion increased significantly to 15.8+/-2.9% (P=0.012) and 0.414+/-0.126 mmol/day (P=0.012), compared to the mixed diet. On the high-oxalate vegetarian diet, oxalate absorption (12.5+/-4.6%, P=0.161) and urinary excretion (0.340+/-0.077 mmol/day, P=0.093) did not change significantly, compared to the mixed diet. A vegetarian diet can only be recommended for calcium oxalate stone patients, if the diet (1) contains the recommended amounts of divalent cations such as calcium and its timing of ingestion to a meal rich in oxalate is considered and (2) excludes foodstuffs with a high content of nutritional factors, such as phytic acid, which are able to chelate calcium.

[Calcium kidney stones. Diagnostic and preventive prospects].

PubMed

Arcidiacono, T; Terranegra, A; Biasion, R; Soldati, L; Vezzoli, G

2007-01-01

Kidney stone disease is one of the main causes of hospitalization in Italy. Its prevalence increased in the last century and is probably still increasing. The pathogenesis of the disease is not known, although two main theories have been elaborated. The first hypothesizes that hydroxyapatite deposition in the interstitium of the renal papillae (Randall's plaque) precedes urinary calcium oxalate precipitation on the ulcered surface of the papilla to form a stone. The second presumes the tubular lumen of Bellini's duct to be the site where calcium-oxalate salts precipitate to form the nucleus for stone formation within the urinary tract. These pathogenetic processes may be favored by different dietary and genetic factors. The genes involved are not known, although many studies have been performed. Polymorphisms of genes coding for the vitamin D receptor, calcium-sensing receptor, interleukin-1 receptor antagonist, and urokinase were found to be associated with kidney stones, but these results have not been replicated. Different nutrients are suspected to predispose patients to calcium kidney stone disease. A high intake of animal proteins, sodium, vitamin C and oxalate has been implicated in stone formation, whereas calcium, alkalis and phytate may have a protective effect. The prevention of calcium stone formation is based on the recognition of risk factors like those already mentioned here. Furthermore, a family history of kidney stones may be useful in identifying subjects predisposed to become calcium stone formers. However, the expectations of the scientific community are turned to the advances in genetics and to the findings of genetic studies, which may provide diagnostic tools and criteria to define the risk profile of the single individual.

Preventive treatment of calcium oxalate crystal deposition with immortal flowers.

PubMed

Orhan, Nilüfer; Onaran, Metin; Şen, İlker; Işık Gönül, İpek; Aslan, Mustafa

2015-04-02

A number of medicinal plants are used for their diuretic, urolithiatic and anti-inflammatory effects on urinary system problems in Turkey and the most common traditional remedy for kidney stones is the tea of immortal flowers. The aim of this study is to evaluate the preventive effect of infusions prepared from capitulums of Helichrysum graveolens (M.Bieb.) Sweet (HG) and Helichrysum stoechas ssp. barellieri (Ten.) Nyman (HS) on formation of kidney stones. Sodium oxalate (Ox-70mg/kg intraperitoneally) was used to induce kidney stones on Wistar albino rats. At the same time, two different doses of the plant extracts (HG: 62.5 and 125mg/kg; HS: 78 and 156mg/kg) were dissolved in the drinking water and administered to animals for 5 days. Potassium citrate was used as positive control in the experiments. During the experiment, water intake, urine volume and body weights of the animals were recorded. At the end of the experiments, liver, kidney and body weights of the animals were determined; biochemical analysis were conducted on urine, blood and plasma samples. Histopathological changes in kidney tissues were examined and statistical analysis were evaluated. HS extract showed the highest preventive effect at 156mg/kg dose (stone formation score: 1.16), whereas a number of kidney stones were maximum in sodium oxalate group (stone formation score: 2.66). Helichrysum extracts decreased urine oxalate and uric acid levels and increased citrate levels significantly. In addition, Helichrysum extracts regulated the negative changes in biochemical and hematological parameters occurred after Ox injection. We conclude that Helichrysum extracts could reduce the formation and growth of kidney stones in Ox-induced urolithiasis and can be beneficial for patients with recurrent stones. In addition, this is the first study on the preventive effect of immortal flowers. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Combining Mean and Standard Deviation of Hounsfield Unit Measurements from Preoperative CT Allows More Accurate Prediction of Urinary Stone Composition Than Mean Hounsfield Units Alone.

PubMed

Tailly, Thomas; Larish, Yaniv; Nadeau, Brandon; Violette, Philippe; Glickman, Leonard; Olvera-Posada, Daniel; Alenezi, Husain; Amann, Justin; Denstedt, John; Razvi, Hassan

2016-04-01

The mineral composition of a urinary stone may influence its surgical and medical treatment. Previous attempts at identifying stone composition based on mean Hounsfield Units (HUm) have had varied success. We aimed to evaluate the additional use of standard deviation of HU (HUsd) to more accurately predict stone composition. We identified patients from two centers who had undergone urinary stone treatment between 2006 and 2013 and had mineral stone analysis and a computed tomography (CT) available. HUm and HUsd of the stones were compared with ANOVA. Receiver operative characteristic analysis with area under the curve (AUC), Youden index, and likelihood ratio calculations were performed. Data were available for 466 patients. The major components were calcium oxalate monohydrate (COM), uric acid, hydroxyapatite, struvite, brushite, cystine, and CO dihydrate (COD) in 41.4%, 19.3%, 12.4%, 7.5%, 5.8%, 5.4%, and 4.7% of patients, respectively. The HUm of UA and Br was significantly lower and higher than the HUm of any other stone type, respectively. HUm and HUsd were most accurate in predicting uric acid with an AUC of 0.969 and 0.851, respectively. The combined use of HUm and HUsd resulted in increased positive predictive value and higher likelihood ratios for identifying a stone's mineral composition for all stone types but COM. To the best of our knowledge, this is the first report of CT data aiding in the prediction of brushite stone composition. Both HUm and HUsd can help predict stone composition and their combined use results in higher likelihood ratios influencing probability.

Urinary stone risk and cola consumption.

PubMed

Herrel, Lindsey; Pattaras, John; Solomon, Tania; Ogan, Kenneth

2012-11-01

To evaluate the effect of cola consumption on urinary stone risk factors in a controlled metabolic environment with a prospective cross-over study. Thirteen participants (10 normal and 3 calcium oxalate stone-formers) underwent 2 6-day phases on a controlled metabolic diet. During phase 1, subjects ingested 1 liter of cola daily, followed by a 3-week washout period. During phase 2, subjects ingested 1 liter of deionized water daily. Twenty-four-hour urine collections and serum metabolic panels were obtained for stone risk factors at the end of each phase. Urine and serum results of the cola phase were compared with those of the water phase. Normal subjects and stone-formers were combined for analysis after determining no significant difference between the 2 groups. No significant differences were found among cola and water treatment groups for normal subjects, stone-formers, or the pooled group. Cola exerts no detectable change in urinary risk factors associated with calcium oxalate stone formation. Cola consumption may not increase stone risk and may be an acceptable alternative source of daily fluid for patients unwilling to increase water consumption. Copyright © 2012 Elsevier Inc. All rights reserved.

Reduced active transcellular intestinal oxalate secretion contributes to the pathogenesis of obesity-associated hyperoxaluria.

PubMed

Amin, Ruhul; Asplin, John; Jung, Daniel; Bashir, Mohamed; Alshaikh, Altayeb; Ratakonda, Sireesha; Sharma, Sapna; Jeon, Sohee; Granja, Ignacio; Matern, Dietrich; Hassan, Hatim

2018-05-01

Most kidney stones are composed of calcium oxalate, and minor changes in urine oxalate affect the stone risk. Obesity is a risk factor for kidney stones and a positive correlation of unknown etiology between increased body size, and elevated urinary oxalate excretion has been reported. Here, we used obese ob/ob (ob) mice to elucidate the pathogenesis of obesity-associated hyperoxaluria. These ob mice have significant hyperoxaluria (3.3-fold) compared with control mice, which is not due to overeating as shown by pair-feeding studies. Dietary oxalate removal greatly ameliorated this hyperoxaluria, confirming that it is largely enteric in origin. Transporter SLC26A6 (A6) plays an essential role in active transcellular intestinal oxalate secretion, and ob mice have significantly reduced jejunal A6 mRNA (- 80%) and total protein (- 62%) expression. While net oxalate secretion was observed in control jejunal tissues mounted in Ussing chambers, net absorption was seen in ob tissues, due to significantly reduced secretion. We hypothesized that the obesity-associated increase in intestinal and systemic inflammation, as reflected by elevated proinflammatory cytokines, suppresses A6-mediated intestinal oxalate secretion and contributes to obesity-associated hyperoxaluria. Indeed, proinflammatory cytokines (elevated in ob mice) significantly decreased intestinal oxalate transport in vitro by reducing A6 mRNA and total protein expression. Proinflammatory cytokines also significantly reduced active mouse jejunal oxalate secretion, converting oxalate transport from net secretion in vehicle-treated tissues to net absorption in proinflammatory cytokines-treated tissues. Thus, reduced active intestinal oxalate secretion, likely secondary to local and systemic inflammation, contributes to the pathogenesis of obesity-associated hyperoxaluria. Hence, proinflammatory cytokines represent potential therapeutic targets. Copyright © 2017 International Society of Nephrology. Published by

Oxalate content of cereals and cereal products.

PubMed

Siener, Roswitha; Hönow, 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.

Oxalate induces mitochondrial dysfunction and disrupts redox homeostasis in a human monocyte derived cell line.

PubMed

Patel, Mikita; Yarlagadda, Vidhush; Adedoyin, Oreoluwa; Saini, Vikram; Assimos, Dean G; Holmes, Ross P; Mitchell, Tanecia

2018-05-01

Monocytes/macrophages are thought to be recruited to the renal interstitium during calcium oxalate (CaOx) kidney stone disease for crystal clearance. Mitochondria play an important role in monocyte function during the immune response. We recently determined that monocytes in patients with CaOx kidney stones have decreased mitochondrial function compared to healthy subjects. The objective of this study was to determine whether oxalate, a major constituent found in CaOx kidney stones, alters cell viability, mitochondrial function, and redox homeostasis in THP-1 cells, a human derived monocyte cell line. THP-1 cells were treated with varying concentrations of CaOx crystals (insoluble form) or sodium oxalate (NaOx; soluble form) for 24h. In addition, the effect of calcium phosphate (CaP) and cystine crystals was tested. CaOx crystals decreased cell viability and induced mitochondrial dysfunction and redox imbalance in THP-1 cells compared to control cells. However, NaOx only caused mitochondrial damage and redox imbalance in THP-1 cells. In contrast, both CaP and cystine crystals did not affect THP-1 cells. Separate experiments showed that elevated oxalate also induced mitochondrial dysfunction in primary monocytes from healthy subjects. These findings suggest that oxalate may play an important role in monocyte mitochondrial dysfunction in CaOx kidney stone disease. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

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

Inaccurate reporting of mineral composition by commercial stone analysis laboratories: implications for infection and metabolic stones.

PubMed

Krambeck, Amy E; Khan, Naseem F; Jackson, Molly E; Lingeman, James E; McAteer, James A; Williams, James C

2010-10-01

We determined the accuracy of stone composition analysis at commercial laboratories. A total of 25 human renal stones with infrared spectroscopy determined composition were fragmented into aliquots and studied with micro computerized tomography to ensure fragment similarity. Representative fragments of each stone were submitted to 5 commercial stone laboratories for blinded analysis. All laboratories agreed on the composition of 6 pure stones. Only 2 of 4 stones (50%) known to contain struvite were identified as struvite at all laboratories. Struvite was reported as a component by some laboratories for 4 stones previously determined not to contain struvite. Overall there was disagreement regarding struvite in 6 stones (24%). For 9 calcium oxalate stones all laboratories reported some mixture of calcium oxalate but the quantity of subtypes differed significantly among laboratories. In 6 apatite containing stones apatite was missed by the laboratories in 20% of samples. None of the laboratories identified atazanavir in a stone containing that antiviral drug. One laboratory reported protein in every sample while all others reported it in only 1. Nomenclature for apatite differed among laboratories with 1 reporting apatite as carbonate apatite and never hydroxyapatite, another never reporting carbonate apatite and always reporting hydroxyapatite, and a third reporting carbonate apatite as apatite with calcium carbonate. Commercial laboratories reliably recognize pure calculi. However, variability in the reporting of mixed calculi suggests a problem with the accuracy of stone analysis results. There is also a lack of standard nomenclature used by laboratories. Copyright © 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

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.

Calcium carbonate crystals promote calcium oxalate crystallization by heterogeneous or epitaxial nucleation: possible involvement in the control of urinary lithogenesis.

PubMed

Geider, S; Dussol, B; Nitsche, S; Veesler, S; Berthézène, P; Dupuy, P; Astier, J P; Boistelle, R; Berland, Y; Dagorn, J C; Verdier, J M

1996-07-01

A large proportion of urinary stones have calcium oxalate (CaOx) as the major mineral phase. In these stones, CaOx is generally associated with minor amounts of other calcium salts. Several reports showing the presence of calcium carbonate (CaCO3) and calcium phosphate in renal stones suggested that crystals of those salts might be present in the early steps of stone formation. Such crystals might therefore promote CaOx crystallization from supersaturated urine by providing an appropriate substrate for heterogeneous nucleation. That possibility was investigated by seeding a metastable solution of 45Ca oxalate with vaterite or calcite crystallites. Accretion of CaOx was monitored by 45Ca incorporation. We showed that (1) seeds of vaterite (the hexagonal polymorph of CaCO3) and calcite (the rhomboedric form) could initiate calcium oxalate crystal growth; (2) in the presence of lithostathine, an inhibitor of CaCO3 crystal growth, such accretion was not observed. In addition, scanning electron microscopy demonstrated that growth occurred by epitaxy onto calcite seeds whereas no special orientation was observed onto vaterite. It was concluded that calcium carbonate crystals promote crystallization of calcium oxalate and that inhibitors controlling calcium carbonate crystal formation in Henle's loop might play an important role in the prevention of calcium oxalate stone formation.

Accurately Diagnosing Uric Acid Stones from Conventional Computerized Tomography Imaging: Development and Preliminary Assessment of a Pixel Mapping Software.

PubMed

Ganesan, Vishnu; De, Shubha; Shkumat, Nicholas; Marchini, Giovanni; Monga, Manoj

2018-02-01

Preoperative determination of uric acid stones from computerized tomography imaging would be of tremendous clinical use. We sought to design a software algorithm that could apply data from noncontrast computerized tomography to predict the presence of uric acid stones. Patients with pure uric acid and calcium oxalate stones were identified from our stone registry. Only stones greater than 4 mm which were clearly traceable from initial computerized tomography to final composition were included in analysis. A semiautomated computer algorithm was used to process image data. Average and maximum HU, eccentricity (deviation from a circle) and kurtosis (peakedness vs flatness) were automatically generated. These parameters were examined in several mathematical models to predict the presence of uric acid stones. A total of 100 patients, of whom 52 had calcium oxalate and 48 had uric acid stones, were included in the final analysis. Uric acid stones were significantly larger (12.2 vs 9.0 mm, p = 0.03) but calcium oxalate stones had higher mean attenuation (457 vs 315 HU, p = 0.001) and maximum attenuation (918 vs 553 HU, p <0.001). Kurtosis was significantly higher in each axis for calcium oxalate stones (each p <0.001). A composite algorithm using attenuation distribution pattern, average attenuation and stone size had overall 89% sensitivity, 91% specificity, 91% positive predictive value and 89% negative predictive value to predict uric acid stones. A combination of stone size, attenuation intensity and attenuation pattern from conventional computerized tomography can distinguish uric acid stones from calcium oxalate stones with high sensitivity and specificity. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Oxalobacter formigenes–Derived Bioactive Factors Stimulate Oxalate Transport by Intestinal Epithelial Cells

PubMed Central

Arvans, Donna; Jung, Yong-Chul; Antonopoulos, Dionysios; Koval, Jason; Granja, Ignacio; Bashir, Mohamed; Karrar, Eltayeb; Roy-Chowdhury, Jayanta; Musch, Mark; Asplin, John; Chang, Eugene

2017-01-01

Hyperoxaluria is a major risk factor for kidney stones and has no specific therapy, although Oxalobacter formigenes colonization is associated with reduced stone risk. O. formigenes interacts with colonic epithelium and induces colonic oxalate secretion, thereby reducing urinary oxalate excretion, via an unknown secretagogue. The difficulties in sustaining O. formigenes colonization underscore the need to identify the derived factors inducing colonic oxalate secretion. We therefore evaluated the effects of O. formigenes culture conditioned medium (CM) on apical 14C-oxalate uptake by human intestinal Caco-2-BBE cells. Compared with control medium, O. formigenes CM significantly stimulated oxalate uptake (>2.4-fold), whereas CM from Lactobacillus acidophilus did not. Treating the O. formigenes CM with heat or pepsin completely abolished this bioactivity, and selective ultrafiltration of the CM revealed that the O. formigenes–derived factors have molecular masses of 10–30 kDa. Treatment with the protein kinase A inhibitor H89 or the anion exchange inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid completely blocked the CM-induced oxalate transport. Knockdown of the oxalate transporter SLC26A6 also significantly restricted the induction of oxalate transport by CM. In a mouse model of primary hyperoxaluria type 1, rectal administration of O. formigenes CM significantly reduced (>32.5%) urinary oxalate excretion and stimulated (>42%) distal colonic oxalate secretion. We conclude that O. formigenes–derived bioactive factors stimulate oxalate transport in intestinal cells through mechanisms including PKA activation. The reduction in urinary oxalate excretion in hyperoxaluric mice treated with O. formigenes CM reflects the in vivo retention of biologic activity and the therapeutic potential of these factors. PMID:27738124

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.

Idiopathic hypercalciuria and formation of calcium renal stones

PubMed Central

Coe, Fredric L.; Worcester, Elaine M.; Evan, Andrew P.

2018-01-01

The most common presentation of nephrolithiasis is idiopathic calcium stones in patients without systemic disease. Most stones are primarily composed of calcium oxalate and form on a base of interstitial apatite deposits, known as Randall’s plaque. By contrast some stones are composed largely of calcium phosphate, as either hydroxyapatite or brushite (calcium monohydrogen phosphate), and are usually accompanied by deposits of calcium phosphate in the Bellini ducts. These deposits result in local tissue damage and might serve as a site of mineral overgrowth. Stone formation is driven by supersaturation of urine with calcium oxalate and brushite. The level of supersaturation is related to fluid intake as well as to the levels of urinary citrate and calcium. Risk of stone formation is increased when urine citrate excretion is <400 mg per day, and treatment with potassium citrate has been used to prevent stones. Urine calcium levels >200 mg per day also increase stone risk and often result in negative calcium balance. Reduced renal calcium reabsorption has a role in idiopathic hypercalciuria. Low sodium diets and thiazide-type diuretics lower urine calcium levels and potentially reduce the risk of stone recurrence and bone diseas PMID:27452364

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.

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 non–stone-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 1–25 and the controlled diet on days 26–30. Twenty-four-hour urine samples were collected on days 28–30. 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

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

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 (case–control study). The proportion of Randall plaque-related stones was assessed over 3 time periods: 1989–1991, 1999–2001, and 2009–2011. 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 1989–1991 period, but the proportion rose to 59% 20 years later (P < 0.001). Patients with plaques experienced their first 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] 0.926–0.994, P = 0.02), weight (OR 0.97, CI 0.934–0.997, P = 0.03), and osteocalcin serum levels (OR 1.12, CI 1.020–1.234, 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

Efficacy of Mixtures of Magnesium, Citrate and Phytate as Calcium Oxalate Crystallization Inhibitors in Urine.

PubMed

Grases, Felix; Rodriguez, Adrian; Costa-Bauza, Antonia

2015-09-01

The main aim of the current study was to evaluate the effectiveness of mixtures of magnesium, citrate and phytate as calcium oxalate crystallization inhibitors. A turbidimetric assay in synthetic urine was performed to obtain induction times for calcium oxalate crystallization in the absence and presence of different mixtures of inhibitors. The morphology of calcium oxalate crystals in the absence or presence of inhibitors and mixtures of the inhibitors was evaluated in 2 crystallization experiments at low and high calcium oxalate supersaturation. The crystals formed were examined using scanning electron microscopy. Examination of crystallization induction times revealed clear inhibitory effects of magnesium, citrate and phytate on calcium oxalate crystallization, supporting usefulness in the treatment and prevention of calcium oxalate nephrolithiasis. Significant synergistic effects between magnesium and phytate were observed. Scanning electron microscopy images revealed that phytate is a powerful crystal growth inhibitor of calcium oxalate, totally preventing the formation of trihydrate and monohydrate. In addition to crystallization inhibition capacity, citrate and magnesium avoided calcium oxalate crystallization by decreasing its supersaturation. The synergistic effect between magnesium and phytate on calcium oxalate crystallization suggests that a combination of these 2 compounds may be highly useful as antilithiasis therapy. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Relative Supersaturation of 24-Hour Urine and Likelihood of Kidney Stones.

PubMed

Prochaska, Megan; Taylor, Eric; Ferraro, Pietro Manuel; Curhan, Gary

2018-05-01

The relative supersaturation of calcium oxalate, calcium phosphate and uric acid is used clinically in kidney stone prevention. The magnitude of the association between relative supersaturation and stone risk requires further quantification. We performed a cross-sectional study using 24-hour urine collections from the NHS (Nurses' Health Study) I and II, and HPFS (Health Professionals Follow-up Study) cohorts to quantify the association between the relative supersaturation of calcium oxalate, calcium phosphate and uric acid, and the likelihood of stone formation. The OR of being a stone former was 5.85 (95% CI 3.40-10.04) in NHS I, 6.38 (95% CI 3.72-11.0) in NHS II and 6.95 (95% CI 3.56-13.6) in HPFS for the highest category of calcium oxalate relative supersaturation compared with less than 1.0. The OR of being a stone former was 1.86 (95% CI 0.94-3.71) in NHS I, 4.37 (95% CI 2.68-7.10) in NHS II and 3.59 (95% CI 2.04-6.31) in HPFS for the highest category of calcium phosphate relative supersaturation compared with less than 1.0. For uric acid relative supersaturation the OR of being a stone former was 4.30 (95% CI 2.34-7.90) in NHS I and 2.74 (95% CI 1.71-4.40) in NHS II for the highest relative supersaturation category compared with less than 1.0. In HPFS the uric acid relative supersaturation was not significantly associated with the likelihood of stone formation. The likelihood of being a stone former increases with higher relative supersaturation of calcium oxalate and calcium phosphate in men and women, and with higher relative supersaturation of uric acid in women. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Crystallization of calcium oxalate in minimally diluted urine

NASA Astrophysics Data System (ADS)

Bretherton, T.; Rodgers, A.

1998-09-01

Crystallization of calcium oxalate was studied in minimally diluted (92%) urine using a mixed suspension mixed product crystallizer in series with a Malvern particle sizer. The crystallization was initiated by constant flow of aqueous sodium oxalate and urine into the reaction vessel via two independent feed lines. Because the Malvern cell was in series with the reaction vessel, noninvasive measurement of particle sizes could be effected. In addition, aliquots of the mixed suspension were withdrawn and transferred to a Coulter counter for crystal counting and sizing. Steady-state particle size distributions were used to determine nucleation and growth kinetics while scanning electron microscopy was used to examine deposited crystals. Two sets of experiments were performed. In the first, the effect of the concentration of the exogenous sodium oxalate was investigated while in the second, the effect of temperature was studied. Calcium oxalate nucleation and growth rates were found to be dependent on supersaturation levels inside the crystallizer. However, while growth rate increased with increasing temperature, nucleation rates decreased. The favored phases were the trihydrate at 18°C, the dihydrate at 38° and the monohydrate at 58°C. The results of both experiments are in agreement with those obtained in other studies that have been conducted in synthetic and in maximally diluted urine and which have employed invasive crystal counting and sizing techniques. As such, the present study lends confidence to the models of urinary calcium oxalate crystallization processes which currently prevail in the literature.

Kidney stones: pathophysiology, diagnosis and management.

PubMed

Cunningham, Priscilla; Noble, Helen; Al-Modhefer, Abdul-Kadhum; Walsh, Ian

2016-11-10

The prevalence of kidney stones is increasing, and approximately 12 000 hospital admissions every year are due to this condition. This article will use a case study to focus on a patient diagnosed with a calcium oxalate kidney stone. It will discuss the affected structures in relation to kidney stones and describe the pathology of the condition. Investigations for kidney stones, differential diagnosis and diagnosis, possible complications and prognosis, will be discussed. Finally, a detailed account of management strategies for the patient with kidney stones will be given, looking at pain management, medical procedures and dietary interventions.

Ascorbate increases human oxaluria and kidney stone risk.

PubMed

Massey, Linda K; Liebman, Michael; Kynast-Gales, Susan A

2005-07-01

Currently, the recommended upper limit for ascorbic acid (AA) intake is 2000 mg/d. However, because AA is endogenously converted to oxalate and appears to increase the absorption of dietary oxalate, supplementation may increase the risk of kidney stones. The effect of AA supplementation on urinary oxalate was studied in a randomized, crossover, controlled design in which subjects consumed a controlled diet in a university metabolic unit. Stoneformers (n = 29; SF) and age- and gender-matched non-stoneformers (n = 19; NSF) consumed 1000 mg AA twice each day with each morning and evening meal for 6 d (treatment A), and no AA for 6 d (treatment N) in random order. After 5 d of adaptation to a low-oxalate diet, participants lived for 24 h in a metabolic unit, during which they were given 136 mg oxalate, including 18 mg 13C2 oxalic acid, 2 h before breakfast; they then consumed a controlled very low-oxalate diet for 24 h. Of the 48 participants, 19 (12 stoneformers, 7 non-stoneformers) were identified as responders, defined by an increase in 24-h total oxalate excretion > 10% after treatment A compared with N. Responders had a greater 24-h Tiselius Risk Index (TRI) with AA supplementation (1.10 +/- 0.66 treatment A vs. 0.76 +/- 0.42 treatment N) because of a 31% increase in the percentage of oxalate absorption (10.5 +/- 3.2% treatment A vs. 8.0 +/- 2.4% treatment N) and a 39% increase in endogenous oxalate synthesis with treatment A than during treatment N (544 +/- 131 A vs. 391 +/- 71 micromol/d N). The 1000 mg AA twice each day increased urinary oxalate and TRI for calcium oxalate kidney stones in 40% of participants, both stoneformers and non-stoneformers.

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

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

Kidney stones

PubMed Central

Khan, Saeed R.; Pearle, Margaret S.; Robertson, William G.; Gambaro, Giovanni; Canales, Benjamin K.; Doizi, Steeve; Traxer, Olivier; Tiselius, Hans-Göran

2017-01-01

Kidney stones are mineral deposits in the renal calyces and pelvis that are found free or attached to the renal papillae. They contain crystalline and organic components and are formed when the urine becomes supersaturated with respect to a mineral. Calcium oxalate is the main constituent of most stones, many of which form on a foundation of calcium phosphate called Randall’s plaques, which are present on the renal papillary surface. Stone formation is highly prevalent, with rates of up to 14.8% and increasing, and a recurrence rate of up to 50% within the first 5 years of the initial stone episode. Obesity, diabetes, hypertension and metabolic syndrome are considered risk factors for stone formation, which, in turn, can lead to hypertension, chronic kidney disease and end-stage renal disease. Management of symptomatic kidney stones has evolved from open surgical lithotomy to minimally invasive endourological treatments leading to a reduction in patient morbidity, improved stone-free rates and better quality of life. Prevention of recurrence requires behavioural and nutritional interventions, as well as pharmacological treatments that are specific for the type of stone. There is a great need for recurrence prevention that requires a better understanding of the mechanisms involved in stone formation to facilitate the development of more-effective drugs. PMID:27188687

Kidney stones.

PubMed

Khan, Saeed R; Pearle, Margaret S; Robertson, William G; Gambaro, Giovanni; Canales, Benjamin K; Doizi, Steeve; Traxer, Olivier; Tiselius, Hans-Göran

2016-02-25

Kidney stones are mineral deposits in the renal calyces and pelvis that are found free or attached to the renal papillae. They contain crystalline and organic components and are formed when the urine becomes supersaturated with respect to a mineral. Calcium oxalate is the main constituent of most stones, many of which form on a foundation of calcium phosphate called Randall's plaques, which are present on the renal papillary surface. Stone formation is highly prevalent, with rates of up to 14.8% and increasing, and a recurrence rate of up to 50% within the first 5 years of the initial stone episode. Obesity, diabetes, hypertension and metabolic syndrome are considered risk factors for stone formation, which, in turn, can lead to hypertension, chronic kidney disease and end-stage renal disease. Management of symptomatic kidney stones has evolved from open surgical lithotomy to minimally invasive endourological treatments leading to a reduction in patient morbidity, improved stone-free rates and better quality of life. Prevention of recurrence requires behavioural and nutritional interventions, as well as pharmacological treatments that are specific for the type of stone. There is a great need for recurrence prevention that requires a better understanding of the mechanisms involved in stone formation to facilitate the development of more-effective drugs.

Properties and function of nephrocalcin: mechanism of kidney stone inhibition or promotion.

PubMed

Nakagawa, Y

1997-03-01

calcium oxalate monohydrate (COM) crystal growth and aggregation. However, isoforms C and D act as promotors for COM crystal growth-kidney stone formation. Measuring the amount of NC in urine from renal cell carcinoma patients and from NC isolated from a supernatant of a primary renal cell carcinoma cells demonstrated the amount of NC increased with disease progression.

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

Kidney Stones After Bariatric Surgery: Risk Assessment and Mitigation.

PubMed

Espino-Grosso, Pedro Mario; Canales, Benjamin Kirk

2017-03-01

Obesity is rampant across the spectrum of age, gender, and race in the Unites States. Paralleling this epidemic, kidney stone prevalence is also rising, affecting nearly 1 in 11 individuals. Bariatric surgical procedures, such as Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), are the most effective weight loss options for morbidly obese or severely obese individuals with comorbidities. A number of studies have linked kidney stone development to bariatric surgical history, particularly RYGB, which portends up to a threefold increase in calcium oxalate stone risk compared with age-matched, obese controls. Stone development after malabsorptive (RYGB) and restrictive (SG) bariatric procedures are driven primarily by alterations in 24-h urine profiles, such as increased urinary oxalate, decreased urine volume, and reduced urinary citrate levels-all of which have been linked to increased kidney stone risk. What clinical recommendations, if any, can be given to reduce kidney stone risk in bariatric kidney stone patients? This review provides not only updated stone incidence and 24-h urine data in this population, but also reassurance-the metabolic alterations that result from bariatric surgery can be successfully mitigated by increased provider awareness, patient education, and a combination of dietary and pharmacological adjustments.

The comparability of oxalate excretion and oxalate:creatinine ratio in the investigation of primary hyperoxaluria: review of data from a referral centre.

PubMed

Clifford-Mobley, Oliver; Tims, Christopher; Rumsby, Gill

2015-01-01

Urine oxalate measurement is an important investigation in the evaluation of renal stone disease. Primary hyperoxaluria (PH) is a rare inherited metabolic disease characterised by persistently elevated urine oxalate, but the diagnosis may be missed in adults until renal failure has developed. Urine oxalate results were reviewed to compare oxalate:creatinine ratio and oxalate excretion, and to estimate the potential numbers of undiagnosed PH. Urine oxalate results from August 2011 to April 2013 were reviewed. Oxalate excretion and oxalate:creatinine ratio were evaluated for 24 h collections and ratio alone for spot urine samples. Oxalate:creatinine ratio and oxalate excretion were moderately correlated (R=0.63) in 24-h urine collections from patients aged 18 years and above. Sex-related differences were found requiring implementation of male and female reference ranges for oxalate:creatinine ratio. Of samples with both ratio and excretion above the reference range, 7% came from patients with confirmed PH. There were 24 patients with grossly elevated urine oxalate who had not been evaluated for PH. Oxalate:creatinine ratio and oxalate excretion were discordant in many patients, which is likely to be a result of intra-individual variation in creatinine output and imprecision in the collection itself. Some PH patients had urine oxalate within the reference range on occasion, and therefore it is not possible to exclude PH on the finding of a single normal result. A significant number of individuals had urine oxalate results well above the reference range who potentially have undiagnosed PH and are consequently at risk of renal failure. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Fragmentation and dusting of large kidney stones using compact, air-cooled, high peak power, 1940-nm, Thulium fiber laser

NASA Astrophysics Data System (ADS)

Hardy, Luke A.; Gonzalez, David A.; Irby, Pierce B.; Fried, Nathaniel M.

2018-02-01

Previous Thulium fiber laser lithotripsy (TFL) studies were limited to a peak power of 70 W (35 mJ / 500 μs), requiring operation in dusting mode with low pulse energy (35 mJ) and high pulse rate (300 Hz). In this study, a novel, compact, air-cooled, TFL capable of operating at up to 500 W peak power, 50 W average power, and 2000 Hz, was tested. The 1940-nm TFL was used with pulse duration (500 μs), average power (10 W), and fiber (270- μm-core) fixed, while pulse energy and pulse rate were changed. A total of 23 large uric acid (UA) stones and 16 large calcium oxalate monohydrate (COM) stones were each separated into 3 modes (Group 1-"Dusting"- 33mJ/300Hz; Group 2-"Fragmentation"-200mJ/50Hz; Group 3-"Dual mode"-Fragmentation then Dusting). The fiber was held manually in contact with stone on a 2-mm-mesh sieve submerged in a flowing saline bath. UA ablation rates were 2.3+/-0.8, 2.3+/-0.2, and 4.4+/-0.8 mg/s and COM ablation rates were 0.4+/-0.1, 1.0+/-0.1, and 0.9+/-0.4 mg/s, for Groups 1, 2, and 3. Dual mode provided 2x higher UA ablation rates than other modes. COM ablation threshold is 3x higher than UA, so dusting provided lower COM ablation rates than other modes. Future studies will explore higher average laser power than 10 W for rapid TFL ablation of large stones.

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. Published by Elsevier Inc.

Dietary treatment of urinary risk factors for renal stone formation. A review of CLU Working Group.

PubMed

Prezioso, Domenico; Strazzullo, Pasquale; Lotti, Tullio; Bianchi, Giampaolo; Borghi, Loris; Caione, Paolo; Carini, Marco; Caudarella, Renata; Ferraro, Manuel; Gambaro, Giovanni; Gelosa, Marco; Guttilla, Andrea; Illiano, Ester; Martino, Marangella; Meschi, Tiziana; Messa, Piergiorgio; Miano, Roberto; Napodano, Giorgio; Nouvenne, Antonio; Rendina, Domenico; Rocco, Francesco; Rosa, Marco; Sanseverino, Roberto; Salerno, Annamaria; Spatafora, Sebastiano; Tasca, Andrea; Ticinesi, Andrea; Travaglini, Fabrizio; Trinchieri, Alberto; Vespasiani, Giuseppe; Zattoni, Filiberto

2015-07-07

stone risk profile is uncertain. Sports beverage do not affect the urinary stone risk profile. HYPEROXALURIA: A diet low in oxalate and/or a calcium intake normal to high (800-1200 mg/day for adults) reduce the urinary excretion of oxalate, conversely a diet rich in oxalates and/or a diet low in calcium increase urinary oxalate. A restriction in protein intake may reduce the urinary excretion of oxalate although a vegetarian diet may lead to an increase in urinary oxalate. Adding bran to a diet low in oxalate cancels its effect of reducing urinary oxalate. Conversely, the addition of supplements of fruit and vegetables to a mixed diet does not involve an increased excretion of oxalate in the urine. The intake of pyridoxine reduces the excretion of oxalate. HYPERURICOSURIA: In patients with renal calcium stones the decrease of the urinary excretion of uric acid after restriction of dietary protein and purine is suggested although not clearly demonstrated. HYPOCITRATURIA: The administration of alkaline-citrates salts is recommended for the medical treatment of renal stone-formers with hypocitraturia, although compliance to this treatment is limited by gastrointestinal side effects and costs. Increased intake of fruit and vegetables (excluding those with high oxalate content) increases citrate excretion and involves a significant protection against the risk of stone formation. Citrus (lemons, oranges, grapefruit, and lime) and non citrus fruits (melon) are natural sources of dietary citrate, and several studies have shown the potential of these fruits and/or their juices in raising urine citrate levels. There are enought basis to advice an adequate fluid intake also in children. Moderate dietary salt restriction and implementation of potassium intake are useful in limiting urinary calcium excretion whereas dietary calcium restriction is not recommended for children with nephrolithiasis. It seems reasonable to advice a balanced consumption of fruit and vegetables and a low

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

Calcium oxalate crystal growth modification; investigations with confocal Raman microscopy

NASA Astrophysics Data System (ADS)

McMulkin, Calum J.; Massi, Massimiliano; Jones, Franca

2017-06-01

Confocal Raman Microscopy (CRM) in combination with a photophysical investigation has been employed to give insight into the interaction between calcium oxalate monohydrate (COM) and a series of tetrazole containing crystal growth modifier's (CGM's), in conjunction with characterisation of morphological changes using scanning electron and optical microscopy. The tetrazole CGM's were found to interact by surface adsorption with minimal morphological changes to the COM crystals however, significant interactions via chemisorption were observed; it was discovered that the chemisorption is sufficiently strong for aggregation of the tetrazole species to occur within the crystal during crystallisation.

Calcium oxalate crystals increased enolase-1 secretion from renal tubular cells that subsequently enhanced crystal and monocyte invasion through renal interstitium.

PubMed

Chiangjong, Wararat; Thongboonkerd, Visith

2016-04-05

Calcium oxalate monohydrate (COM) crystals cause kidney stone disease by still unclear mechanisms. The present study aimed to characterize changes in secretion of proteins from basolateral compartment of renal tubular epithelial cells after exposure to COM crystals and then correlated them with the stone pathogenesis. Polarized MDCK cells were cultivated in serum-free medium with or without 100 μg/ml COM crystals for 20 h. Secreted proteins collected from the lower chamber (basolateral compartment) were then resolved in 2-D gels and visualized by Deep Purple stain (n = 5 gels/group). Spot matching and intensity analysis revealed six protein spots with significantly altered levels in COM-treated samples. These proteins were then identified by tandem mass spectrometry (Q-TOF MS/MS), including enolase-1, phosphoglycerate mutase-1, actinin, 14-3-3 protein epsilon, alpha-tubulin 2, and ubiquitin-activating enzyme E1. The increased enolase-1 level was confirmed by Western blot analysis. Functional analysis revealed that enolase-1 dramatically induced COM crystal invasion through ECM migrating chamber in a dose-dependent manner. Moreover, enolase-1 bound onto U937 monocytic cell surface markedly enhanced cell migration through the ECM migrating chamber. In summary, our data indicated that the increased secretory enolase-1 induced by COM crystals played an important role in crystal invasion and inflammatory process in renal interstitium.

Hydroxyproline Metabolism and Oxalate Synthesis in Primary Hyperoxaluria.

PubMed

Fargue, Sonia; Milliner, Dawn S; Knight, John; Olson, Julie B; Lowther, W Todd; Holmes, Ross P

2018-06-01

Background Endogenous oxalate synthesis contributes to calcium oxalate stone disease and is markedly increased in the inherited primary hyperoxaluria (PH) disorders. The incomplete knowledge regarding oxalate synthesis complicates discovery of new treatments. Hydroxyproline (Hyp) metabolism results in the formation of oxalate and glycolate. However, the relative contribution of Hyp metabolism to endogenous oxalate and glycolate synthesis is not known. Methods To define this contribution, we performed primed, continuous, intravenous infusions of the stable isotope [ 15 N, 13 C 5 ]-Hyp in nine healthy subjects and 19 individuals with PH and quantified the levels of urinary 13 C 2 -oxalate and 13 C 2 -glycolate formed using ion chromatography coupled to mass detection. Results The total urinary oxalate-to-creatinine ratio during the infusion was 73.1, 70.8, 47.0, and 10.6 mg oxalate/g creatinine in subjects with PH1, PH2, and PH3 and controls, respectively. Hyp metabolism accounted for 12.8, 32.9, and 14.8 mg oxalate/g creatinine in subjects with PH1, PH2, and PH3, respectively, compared with 1.6 mg oxalate/g creatinine in controls. The contribution of Hyp to urinary oxalate was 15% in controls and 18%, 47%, and 33% in subjects with PH1, PH2, and PH3, respectively. The contribution of Hyp to urinary glycolate was 57% in controls, 30% in subjects with PH1, and <13% in subjects with PH2 or PH3. Conclusions Hyp metabolism differs among PH types and is a major source of oxalate synthesis in individuals with PH2 and PH3. In patients with PH1, who have the highest urinary excretion of oxalate, the major sources of oxalate remain to be identified. Copyright © 2018 by the American Society of Nephrology.

The influence of freezer storage of urine samples on the BONN-Risk-Index for calcium oxalate crystallization.

PubMed

Laube, Norbert; Zimmermann, Diana J

2004-01-01

This study was performed to quantify the effect of a 1-week freezer storage of urine on its calcium oxalate crystallization risk. Calcium oxalate is the most common urinary stone material observed in urolithiasis patients in western and affluent countries. The BONN-Risk-Index of calcium oxalate crystallization risk in human urine is determined from a crystallization experiment performed on untreated native urine samples. We tested the influence of a 1-week freezing on the BONN-Risk-Index value as well as the effect of the sample freezing on the urinary osmolality. In vitro crystallization experiments in 49 native urine samples from stone-forming and non-stone forming individuals were performed in order to determine their calcium oxalate crystallization risk according to the BONN-Risk-Index approach. Comparison of the results derived from original sample investigations with those obtained from the thawed aliquots by statistical evaluation shows that i) no significant deviation from linearity between both results exists and ii) both results are identical by statistical means. This is valid for both, the BONN-Risk-Index and the osmolality data. The differences in the BONN-Risk-Index results of both procedures of BONN-Risk-Index determination, however, exceed the clinically acceptable difference. Thus, determination of the urinary calcium oxalate crystallization risk from thawed urine samples cannot be recommended.

Effects of Juice Processing on Oxalate Contents in Carambola Juice Products.

PubMed

Huynh, Nha K; Nguyen, Ha V H

2017-09-01

Effects of processing methods including pressing, enzyme-assisted extraction, lactic acid fermentation by Lactobacillus acidophilus, and alcohol fermentation by Saccharomyces cerevisiae on total and soluble oxalate contents of carambola juices were studied. In comparison with pressing, the use of enzyme increased juice yields (15.89-17.29%), but resulted in higher total oxalate (1.60-1.73 times) and soluble oxalate contents (1.16-1.49 times). In addition, extension of enzyme incubation periods led to an increase in soluble oxalate contents in the products (p < 0.05). On the other hand, alcohol fermentation with Saccharomyces cerevisiae from 1 to 5 weeks reduced 37-58% of total oxalate and 39-59% of soluble oxalate contents. Prolonged fermentation also demonstrated better reduction of oxalate contents. Meanwhile, lactic acid fermentation using Lactobacillus acidophilus had no effects on total and soluble oxalate contents in carambola juices. These results suggested that carambola juice products should only be consumed moderately, and that alcohol fermentation could be a potential method to reduce oxalate contents in foods in order to prevent the risks of forming kidney stones.

Impact of power index, hydroureteronephrosis, stone size, and composition on the efficacy of in situ boosted ESWL for primary proximal ureteral calculi.

PubMed

Singh, I; Gupta, N P; Hemal, A K; Dogra, P N; Ansari, M S; Seth, A; Aron, M

2001-07-01

The efficacy, safety, feasibility, and outcome of in situ treatment applied to select proximal ureteral calculi was assessed and analyzed with a view to avoiding auxiliary interventions and providing high clearance rates in the shortest possible time. We studied the impact of several clinically important variables, including power index, degree of hydroureteronephrosis (HDUN), stone size, and composition on the efficacy of sequential in situ boosted extracorporeal shock wave lithotripsy (ESWL) in a select group. The power index requirement for the in situ boosted protocol and the impact of the stone size/composition, degree of HDUN, and clearance rates were also analyzed. An in situ (no instrumentation) boosted protocol was applied to 130 primary unimpacted proximal ureteral calculi with no prior intervention. A typical session with the Siemens Lithostar Plus comprised 3000 shock waves, in installments of 500, deployed at a power setting of 1 to 4 kV with a gradual stepwise escalation. Sequential boosted additional sessions of ESWL were administered on days 2, 7, and 14, tailored to the degree of fragmentation, clearance status, and amount of residual stone bulk. Several parameters (shock waves, kilovolts used, fluoroscopy time, number of sessions, stone size, composition, fragmentation, clearance, and HDUN) were recorded and the results analyzed statistically. The results were excellent in 83.8%, with a mean duration to complete clearance of 11.3 days. In situ ESWL failed in 7.69%, and the auxiliary intervention rate was 10.7%. Pre-ESWL HDUN was present in 78.3%, the mean power index was 184.6/session/case, and the average stone burden was 8.9 mm(2). Calcium oxalate monohydrate was the most common stone (56%). Renal colic was the most common side effect observed. The power index, fragmentation at the first session, and stone size were found to be the most favorable significant variables affecting stone clearance. The degree of HDUN, number of sessions, and stone

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

Extracellular nucleotides inhibit oxalate transport by human intestinal Caco-2-BBe cells through PKC-δ activation

PubMed Central

Amin, Ruhul; Sharma, Sapna; Ratakonda, Sireesha

2013-01-01

Nephrolithiasis remains a major health problem in Western countries. Seventy to 80% of kidney stones are composed of calcium oxalate, and small changes in urinary oxalate affect risk of kidney stone formation. Intestinal oxalate secretion mediated by the anion exchanger SLC26A6 plays an essential role in preventing hyperoxaluria and calcium oxalate nephrolithiasis, indicating that understanding the mechanisms regulating intestinal oxalate transport is critical for management of hyperoxaluria. Purinergic signaling modulates several intestinal processes through pathways including PKC activation, which we previously found to inhibit Slc26a6 activity in mouse duodenal tissue. We therefore examined whether purinergic stimulation with ATP and UTP affects oxalate transport by human intestinal Caco-2-BBe (C2) cells. We measured [14C]oxalate uptake in the presence of an outward Cl− gradient as an assay of Cl−/oxalate exchange activity, ≥50% of which is mediated by SLC26A6. We found that ATP and UTP significantly inhibited oxalate transport by C2 cells, an effect blocked by the PKC inhibitor Gö-6983. Utilizing pharmacological agonists and antagonists, as well as PKC-δ knockdown studies, we observed that ATP inhibits oxalate transport through the P2Y2 receptor, PLC, and PKC-δ. Biotinylation studies showed that ATP inhibits oxalate transport by lowering SLC26A6 surface expression. These findings are of potential relevance to pathophysiology of inflammatory bowel disease-associated hyperoxaluria, where supraphysiological levels of ATP/UTP are expected and overexpression of the P2Y2 receptor has been reported. We conclude that ATP and UTP inhibit oxalate transport by lowering SLC26A6 surface expression in C2 cells through signaling pathways including the P2Y2 purinergic receptor, PLC, and PKC-δ. PMID:23596171

Effect of Cystone® on urinary composition and stone formation over a one year period.

PubMed

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

2011-07-15

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. Copyright © 2011 Elsevier GmbH. All rights reserved.

Loss of Cystic Fibrosis Transmembrane Regulator Impairs Intestinal Oxalate Secretion.

PubMed

Knauf, Felix; Thomson, Robert B; Heneghan, John F; Jiang, Zhirong; Adebamiro, Adedotun; Thomson, Claire L; Barone, Christina; Asplin, John R; Egan, Marie E; Alper, Seth L; Aronson, Peter S

2017-01-01

Patients with cystic fibrosis have an increased incidence of hyperoxaluria and calcium oxalate nephrolithiasis. Net intestinal absorption of dietary oxalate results from passive paracellular oxalate absorption as modified by oxalate back secretion mediated by the SLC26A6 oxalate transporter. We used mice deficient in the cystic fibrosis transmembrane conductance regulator gene (Cftr) to test the hypothesis that SLC26A6-mediated oxalate secretion is defective in cystic fibrosis. We mounted isolated intestinal tissue from C57BL/6 (wild-type) and Cftr -/- mice in Ussing chambers and measured transcellular secretion of [ 14 C]oxalate. Intestinal tissue isolated from Cftr -/- mice exhibited significantly less transcellular oxalate secretion than intestinal tissue of wild-type mice. However, glucose absorption, another representative intestinal transport process, did not differ in Cftr -/- tissue. Compared with wild-type mice, Cftr -/- mice showed reduced expression of SLC26A6 in duodenum by immunofluorescence and Western blot analysis. Furthermore, coexpression of CFTR stimulated SLC26A6-mediated Cl - -oxalate exchange in Xenopus oocytes. In association with the profound defect in intestinal oxalate secretion, Cftr -/- mice had serum and urine oxalate levels 2.5-fold greater than those of wild-type mice. We conclude that defective intestinal oxalate secretion mediated by SLC26A6 may contribute to the hyperoxaluria observed in this mouse model of cystic fibrosis. Future studies are needed to address whether similar mechanisms contribute to the increased risk for calcium oxalate stone formation observed in patients with cystic fibrosis. Copyright © 2016 by the American Society of Nephrology.

Oxalobacter formigenes Colonization and Oxalate Dynamics in a Mouse Model

PubMed Central

Li, Xingsheng; Ellis, Melissa L.

2015-01-01

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

Thulium fiber laser ablation of kidney stones using a 50-μm-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-μm-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 μm) 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-μm-core-diameter, 85-μm-outer-diameter, low-OH silica fiber is characterized for TFL ablation of human calcium oxalate monohydrate urinary stones, ex vivo. The 50-μm-core fiber consumes approximately 30 times less cross-sectional area inside the single working channel of a ureteroscope than the standard 270-μm-core fiber currently used in the clinic. The ureteroscope working channel flow rate, including the 50-μm fiber, decreased by only 10% with no impairment of ureteroscope deflection. The fiber delivered up to 15.4±5.9 W under extreme bending (5-mm-radius) conditions. The stone ablation rate measured 70±22 μg/s for 35-mJ-pulse-energy, 500-μs-pulse-duration, and 50-Hz-pulse-rate. Stone retropulsion and fiber burnback averaged 201±336 and 3000±2600 μm, respectively, after 2 min. With further development, thulium fiber laser lithotripsy using ultra-small, 50-μm-core fibers may introduce new integration and miniaturization possibilities and potentially provide an alternative to conventional Holmium:YAG laser lithotripsy using larger fibers.

In vivo characterization of urinary calculi on dual-energy CT: going a step ahead with sub-differentiation of calcium stones.

PubMed

Acharya, Sudeep; Goyal, Ankur; Bhalla, Ashu Seith; Sharma, Raju; Seth, Amlesh; Gupta, Arun Kumar

2015-07-01

The role of dual-energy computed tomography (DECT) in characterization of urinary calculi is evolving and literature regarding differentiation of calcium calculi is sparse and confounding. To evaluate the capability of DECT in assessing the urinary calculi composition in vivo, especially in differentiating various types of calcium calculi. One hundred and twenty patients underwent DECT for characterization of urinary calculi. Seventy patients with 114 calculi, including 93 calcium stones, were retrospectively analyzed. DE ratios and attenuation differences were compared using ANOVA and receiver-operating-characteristic (ROC) analysis was done to predict cut-off values, in particular for detecting calcium-oxalate-monohydrate (COM) stones. DE ratio ≤1.14 accurately detected uric acid calculi, ≥1.29 was definitive for calcium and intermediate values were characteristic of cystine stones. DE ratios were significantly different between group 1 (COM [n = 32]; mean 1.376 ± 0.041), group 2 ([calcium oxalate dihydrate (COD) + COM] [n = 51]; 1.416 ± 0.048), and group 3 ([carbonate apatite (CaP) + COD + COM] [n = 10]; 1.468 ± 0.038) (group 1 vs. 2, P = 0.001; 1 vs. 3, P = 0.000; 2 vs. 3, P = 0.004). More importantly, pure COM calculi (group 1) had significantly lower DE ratio compared with mixed calcium calculi (groups 2 and 3) (P = 0.000). Attenuation differences (between low and high kV images) could not distinguish between COM and mixed calculi. ROC analysis for detection of COM calculi yielded AUC of 0.770 with cut-off DE ratio 1.385 (sensitivity 65.6%, specificity 82%) and value <1.335 was seen only with COM calculi (100% specificity). DECT can be employed for in vivo differentiation of various types of calculi and for detection of relatively lithotripsy-resistant COM calculi. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Urinary oxalate to creatinine ratios in healthy Turkish schoolchildren.

PubMed

Dursun, Ismail; Çelik, İlknur; Poyrazoglu, Hakan M; Köse, Kader; Tanrıkulu, Esen; Sahin, Habibe; Yılmaz, Kenan; Öztürk, Ahmet; Yel, Sibel; Gündüz, Zübeyde; Düşünsel, Ruhan

2017-11-01

we aimed to establish reference values for urinary oxalate to creatinine ratios in healthy children aged 6-15 years and to investigate the relationship between their nutritional habits and oxalate excretion. Random urine specimens from 953 healthy children aged 6-15 years were obtained and analyzed for oxalate and creatinine. Additionally, a 24-h dietary recall form was prepared and given to them. The ingredient composition of the diet was calculated. The children were divided into three groups according to age: Group I (69 years, n = 353), Group II (10-12 years, n = 335), and Group III (13-15 years, n = 265). The 95th percentile of the oxalate to creatinine ratio for subjects aged 6-9, 10-12, and 13-15 years were 0.048, 0.042, and 0.042 mg/mg, respectively. The oxalate to creatinine ratio was significantly higher in Group 1 than in Group 2 and Group 3. Urinary oxalate excretion was positively correlated with increased protein intake and negatively correlated with age. A significant positive correlation was determined between urinary oxalate excretion and the proline, serine, protein, and glycine content of diet. Dietary proline intake showed a positive correlation with the urine oxalate to creatinine ratio and was found to be an independent predictor for urinary oxalate. These data lend support to the idea that every country should have its own normal reference values to determine the underlying metabolic risk factor for kidney stone disease since regional variation in the dietary intake of proteins and other nutrients can affect normal urinary excretion of oxalate.

Kidney stone composition in the Kingdom of Saudi Arabia
.

PubMed

Amir, Abdulrazack; Matlaga, Brian R; Ziemba, Justin B; Sheikh, Salwa

2018-05-01

Urolithiasis is a globally-distributed disease; however, its prevalence varies across countries and regions. Countries in the Middle East have been reported to have particularly high nephrolithiasis prevalence rates. To date, however, we have an incomplete understanding of the composition of stones seen in this region. Therefore, we performed a study to characterize stone composition over a 14-year period in the Eastern Province of the Kingdom of Saudi Arabia (KSA). A retrospective review of all adult patients who had the composition of their upper urinary tract calculi analyzed at Johns Hopkins Aramco Healthcare (JHAH) between 1999 and 2013 was performed. Patient demographics and pathology results were obtained from the electronic medical record. A total of 1,747 stones were analyzed in the study period. The results are presented in the Table. Male patients predominated (79%). For both men and women, the majority of stones were calcium oxalate: 85.2% male, 85.9% female. Uric acid stones were the next most common: 10.1% male; 9.0% female. Overall, there were no significant differences between gender with regards to the distribution of stone types. This study represents one of the largest characterizations of stone composition in the Middle East. There remains a significant gender disparity in stone prevalence in the Eastern Province of KSA, with males affected to a significantly greater extent. Calcium oxalate is the most common type of stone, and this is true for both men and women. Future investigations of dietary and environmental factors can build on these initial epidemiologic findings.
.

HOW DO STONES FORM? IS UNIFICATION OF THEORIES ON STONE FORMATION POSSIBLE?

PubMed Central

Bird, Victoria Y.; Khan, Saeed R.

2017-01-01

Summary There are two basic pathways for formation of calcium based kidney stones. Most idiopathic calcium oxalate (CaOx) stones are formed in association with sub-epithelial plaques of calcium phosphate (CaP), known as Randall’s plaques, on renal papillary surfaces. Crystal formation and retention within the terminal collecting ducts, the ducts of Bellini, leading to the formation of Randall’s plugs, is the other pathway. Both pathways require supersaturation leading to crystallization, regulated by various crystallization modulators produced in response to changing urinary conditions. High supersaturation, as a result of a variety of genetic and environmental factors, leads to crystallization in the terminal collecting ducts, eventually plugging their openings into the renal pelvis. Stasis behind the plugs may lead to the formation of attached or unattached stones in the tubular lumen. Deposition of crystals on the plug surface facing the pelvic or tubular urine may result in stone formation on the Randall’s plugs. Kidneys of idiopathic stone formers may be subjected to oxidative stress as a result of increased urinary excretion of calcium/oxalate/phosphate and/or decrease in the production of functional crystallization inhibitors or in relation to co-morbidities such as hypertension, atherosclerosis, or acute kidney injury. We have proposed that production of reactive oxygen species (ROS) causes dedifferentiation of epithelial/endothelial cells into osteoblast type cells and deposition of CaP in the basement membrane of renal tubules or vessels. Growth, aggregation and melding of CaP crystals leads to the formation of plaque which grows by further calcification of interstitial collagen and membranous vesicles. Plaque becomes exposed to pelvic urine once the covering papillary epithelium is breached. Surface layers of CaP are replaced by CaOx through direct transformation or demineralization of CaP and mineralization of CaOx. Alternatively, or in addition

Obesity and kidney stone disease: a systematic review.

PubMed

Carbone, Antonio; Al Salhi, Yazan; Tasca, Andrea; Palleschi, Giovanni; Fuschi, Andrea; De Nunzio, Cosimo; Bozzini, Giorgio; Mazzaferro, Sandro; Pastore, Antonio L

2018-05-31

Currently, abdominal obesity has reached an epidemic stage and obesity represents an important challenge for worldwide health authorities. Epidemiologic studies have demonstrated that the stone risk incidence increases with body mass index (BMI), through multiple pathways. Metabolic syndrome and diabetes are associated with an increased renal stones disease incidence. The aim of this systematic review was to investigate the prevalence, morbidity, risk factors involved in the association between obesity and urolithiasis. The search involved finding relevant studies from MEDLINE, EMBASE, Ovid, the Cochrane Central Register of Controlled Trials, CINAHL, Google Scholar, and individual urological journals between January 2001 and May 2017. The inclusion criteria were for studies written in the English language, reporting on the association between obesity and urinary stones. 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 observed frequently in these patients. Insulin resistance is thought to alter the renal acid-base metabolism, resulting in a lower urine pH, and increasing the risk of uric acid stone disease. Obesity is also associated with excess nutritional intake of lithogenic substances and with an increase in urinary tract infection incidence. Recent studies highlighted that renal stone disease increases the risk of myocardial infarction, progression of chronic kidney disease, and diabetes. Contemporary, bariatric surgery has been shown to be associated with hyperoxaluria and oxalate nephropathy. Certainly, the many health risks of obesity, including nephrolithiasis, will add more burden on urologists and nephrologists. Obesity related nephrolithiasis seems to necessitate weight loss as primary treatment, but the recognition of the associated complications is necessary to prevent induction of new

Comparison of Tissue Injury from Focused Ultrasonic Propulsion of Kidney Stones Versus Extracorporeal Shock Wave Lithotripsy

PubMed Central

Connors, Bret A.; Evan, Andrew P.; Blomgren, Philip M.; Hsi, Ryan S.; Harper, Jonathan D.; Sorensen, Mathew D.; Wang, Yak-Nam; Simon, Julianna C.; Paun, Marla; Starr, Frank; Cunitz, Bryan W.; Bailey, Michael R.; Lingeman, James E.

2013-01-01

Purpose Focused ultrasonic propulsion is a new non-invasive technique designed to move kidney stones and stone fragments out of the urinary collecting system. However, the extent of tissue injury associated with this technique is not known. As such, we quantitated the amount of tissue injury produced by focused ultrasonic propulsion under simulated clinical treatment conditions, and under conditions of higher power or continuous duty cycles, and compared those results to SWL injury. Materials and Methods A human calcium oxalate monohydrate stone and/or nickel beads were implanted (with ureteroscopy) into 3 kidneys of live pigs (45–55 kg) and repositioned using focused ultrasonic propulsion. Additional pig kidneys were exposed to SWL level pulse intensities or continuous ultrasound exposure of 10 minutes duration (ultrasound probe either transcutaneous or on the kidney). These kidneys were compared to 6 kidneys treated with an unmodified Dornier HM3 Lithotripter (2400 shocks, 120 SWs/min and 24 kV). Histological analysis was performed to assess the volume of hemorrhagic tissue injury created by each technique (% functional renal volume, FRV). Results SWL produced a lesion of 1.56±0.45% FRV. Ultrasonic propulsion produced no detectable lesion with the simulated clinical treatment. A lesion of 0.46±0.37% FRV or 1.15±0.49% FRV could be produced if excessive treatment parameters were used while the ultrasound probe was placed on the kidney. Conclusions Focused ultrasonic propulsion produced no detectable morphological injury to the renal parenchyma when using clinical treatment parameters and produced injury comparable in size to SWL when using excessive treatment parameters. PMID:23917165

Rare calcium oxalate monohydrate calculus attached to the wall of the renal pelvis.

PubMed

Grases, Felix; Costa-Bauza, Antonia; Prieto, Rafael M; Saus, Carlos; Servera, Antonio; García-Miralles, Reyes; Benejam, Joan

2011-04-01

Most renal calculi can be classified using well-established criteria in a manner that reflects both composition and fine structure under specific pathophysiological conditions. However, when a large patient population is considered, rare renal calculi invariably appear, some of which have never been classified; careful study is required to establish stone etiology in such cases. The patient in the present case report formed two types of calculi. One was attached on the wall of the renal pelvis near the ureter and part of the calculus was embedded inside pelvic renal tissue. The calculus developed on an ossified calcification located in the pelvis tissue. Current knowledge on the development of calcification in soft tissues suggests a pre-existing injury as an inducer of its development. A mechanism of calculus formation is proposed. The second stone was a typical jack-stone calculus. © 2011 The Japanese Urological Association.

Effects of microgravity on renal stone risk assessment

NASA Technical Reports Server (NTRS)

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

1992-01-01

Physiologic changes induced during human exposure to the microgravity environment of space may contribute to an increased potential for renal stone formation. Renal stone risk factors obtained 10 days before flight and immediately after return to earth indicated that calcium oxalate and uric acid stone-forming potential was increased after space flights of 4-10 days. These data describe the need for examining renal stone risk during in-flight phases of space missions. Because of limited availability of space and refrigerated storage on spacecraft, effective methods must be developed for collecting urine samples in-flight and for preserving (or storing) them at temperatures and under conditions commensurate with mission constraints.

Urinary oxalate to creatinine ratios in healthy Turkish schoolchildren

PubMed Central

Dursun, Ismail; Çelik, İlknur; Poyrazoglu, Hakan M.; Tanrıkulu, Esen; Sahin, Habibe; Yılmaz, Kenan; Öztürk, Ahmet; Yel, Sibel; Gündüz, Zübeyde; Düşünsel, Ruhan

2017-01-01

Abstract Aim: we aimed to establish reference values for urinary oxalate to creatinine ratios in healthy children aged 6–15 years and to investigate the relationship between their nutritional habits and oxalate excretion. Materials and methods: Random urine specimens from 953 healthy children aged 6–15 years were obtained and analyzed for oxalate and creatinine. Additionally, a 24-h dietary recall form was prepared and given to them. The ingredient composition of the diet was calculated. The children were divided into three groups according to age: Group I (69 years, n = 353), Group II (10–12 years, n = 335), and Group III (13–15 years, n = 265). Results: The 95th percentile of the oxalate to creatinine ratio for subjects aged 6–9, 10–12, and 13–15 years were 0.048, 0.042, and 0.042 mg/mg, respectively. The oxalate to creatinine ratio was significantly higher in Group 1 than in Group 2 and Group 3. Urinary oxalate excretion was positively correlated with increased protein intake and negatively correlated with age. A significant positive correlation was determined between urinary oxalate excretion and the proline, serine, protein, and glycine content of diet. Dietary proline intake showed a positive correlation with the urine oxalate to creatinine ratio and was found to be an independent predictor for urinary oxalate. Conclusions: These data lend support to the idea that every country should have its own normal reference values to determine the underlying metabolic risk factor for kidney stone disease since regional variation in the dietary intake of proteins and other nutrients can affect normal urinary excretion of oxalate. PMID:27846788

Atypical findings in a patient with a renal milky stone including a cake of stone.

PubMed

Uesugi, Tatsuya; Ichikawa, Takaharu

2006-08-01

A 54-year-old woman was admitted to our department with the diagnosis of a renal calculus. She exhibited dull left flank pain. A plain film revealed a round opaque calcific density in the left kidney in the supine and the upright position. There was no connection between the calcification and the renal collecting system by retrograde pyelography. Computed tomography in the supine position showed a rounded calcification in the left renal parenchyma without a semilunar configuration. She was diagnosed with left renal calyceal diverticula calculi. She underwent a surgical intervention which found a renal milky stone including a 10-mm. diameter stone. The examination of the fluid and the stone material disclosed three components: calcium phosphate, calcium oxalate and calcium carbonate. The present case is interesting because its characteristics differ from the common features of renal milky stone.

Evaluation of biochemical urinary stone composition and its relationship to tap water hardness in Qom province, central Iran.

PubMed

Moslemi, Mohammad Kazem; Saghafi, Hossein; Joorabchin, Seyed Mohammad Amin

2011-01-01

The aim of this study was to evaluate the biochemical stone composition in general population of Qom province, central Iran, and its relationship with high tap water hardness. In a prospective study, from March 2008 to July 2011, biochemical analysis of urinary stones in patients living in Qom province for at least 5 years was performed. Stones were retrieved by spontaneous passage, endoscopic or open surgery, and after extracorporeal shockwave lithotripsy. Demographic findings and the drinking water supply of patients were evaluated and compared with biochemical stone analysis. Stone analysis was performed in 255 patients. The most dominant composition of urinary stones was calcium oxalate (73%), followed by uric acid (24%), ammonium urate (2%), and cystine (1%). The peak incidence of urinary stone was in patients in their forties. Overall male to female ratio was 4.93:1. The dominant stone composition in inhabitants of central Iran, where tap water hardness is high, was calcium oxalate stones. On the basis of this study, biochemical urinary stone composition of Qom does not differ from other regions of Iran with lower water hardness.

Continuous-wave and quasi-continuous wave thulium-doped all-fiber laser: implementation on kidney stone fragmentations.

PubMed

Pal, Debasis; Ghosh, Aditi; Sen, Ranjan; Pal, Atasi

2016-08-10

A continuous-wave (CW) as well as quasi-continuous wave (QCW) thulium-doped all-fiber laser at 1.94 μm has been designed for targeting applications in urology. The thulium-doped active fiber with an octagonal-shaped inner cladding is pumped at 793 nm to achieve stable CW laser power of 10 W with 32% lasing efficiency (against launched pump power). The linear variation of laser power with pump offers a scope of further power scaling. A QCW operation with variation of duty cycle from 0.5% to 90%, repetition rate from 0.1 Hz to 1 kHz, and pulse width from 40 μs to 2 s has been presented. Laser power of 9.5 W in CW mode of operation and average power of 5.2 W with energy range of 10.4-104 mJ in QCW mode of operation has been employed to fragment calcium oxalate monohydrate kidney stones (size of 1.5-4 cm) having different colors and composition. Dependence of ablation threshold, ablation rate, and average fragmented particle size on the average power and energy has been studied. One minute of laser exposure results in fragmentation of a stone surface with ablation rate of 8  mg/min having minimum particle size of 6.54 μm with an average size of 20-100 μm ensuring the natural removal of fragmented parts through the urethra.

Microbial Community Transplant Results in Increased and Long-Term Oxalate Degradation

PubMed Central

Miller, Aaron W.; Oakeson, Kelly F.; Dale, Colin; Dearing, M. Denise

2016-01-01

Gut microbes are essential for the degradation of dietary oxalate, and this function may play a role in decreasing the incidence of kidney stones. However, many oxalate-degrading bacteria are susceptible to antibiotics and the use of oxalate-degrading probiotics has only led to an ephemeral reduction in urinary oxalate. The objective of the current study was to determine the efficacy of using whole-community microbial transplants from a wild mammalian herbivore, Neotoma albigula, to increase oxalate degradation over the long term in the laboratory rat, Rattus norvegicus. We quantified the change in total oxalate degradation in lab rats immediately after microbial transplants and at 2- and 9-month intervals following microbial transplants. Additionally, we tracked the fecal microbiota of the lab rats, with and without microbial transplants, using high-throughput Illumina sequencing of a hyper-variable region of the 16S rRNA gene. Microbial transplants resulted in a significant increase in oxalate degradation, an effect that persisted 9 months after the initial transplants. Functional persistence was corroborated by the transfer, and persistence of a group of bacteria previously correlated with oxalate consumption in N. albigula, including an anaerobic bacterium from the genus Oxalobacter known for its ability to use oxalate as a sole carbon source. The results of this study indicate that whole-community microbial transplants are an effective means for the persistent colonization of oxalate-degrading bacteria in the mammalian gut. PMID:27312892

Changes in urinary risk profile after short-term low sodium and low calcium diet in recurrent Swiss kidney stone formers.

PubMed

Seeger, Harald; Kaelin, Andrea; Ferraro, Pietro M; Weber, Damian; Jaeger, Philippe; Ambuehl, Patrice; Robertson, William G; Unwin, Robert; Wagner, Carsten A; Mohebbi, Nilufar

2017-12-04

Kidney stone disease is common in industrialized countries. Recently, it has attracted growing attention, because of its significant association with adverse renal outcomes, including end stage renal disease. Calcium-containing kidney stones are frequent with high recurrence rates. While hypercalciuria is a well-known risk factor, restricted intake of animal protein and sodium, combined with normal dietary calcium, has been shown to be more effective in stone prevention compared with a low-calcium diet. Notably, the average sodium intake in Switzerland is twice as high as the WHO recommendation, while the intake of milk and dairy products is low. We retrospectively analyzed Swiss recurrent kidney stone formers (rKSF) to test the impact of a low-sodium in combination with a low-calcium diet on the urinary risk profile. In patients with recurrent calcium oxalate containing stones, we investigated both, the consequence of a low-sodium diet on urinary volume and calcium excretion, and the influence of a low-sodium low-calcium diet on urinary oxalate excretion. Of the 169 patients with CaOx stones, 49 presented with hypercalciuria at baseline. The diet resulted in a highly significant reduction in 24-h urinary sodium and calcium excretion: from 201 ± 89 at baseline to 128 ± 88 mmol/d for sodium (p < 0.0001), and from 5.67 ± 3.01 to 4.06 ± 2.46 mmol/d (p < 0.0001) for calcium, respectively. Urine volume remained unchanged. Notably, no increase in oxalate excretion occurred on the restricted diet (0.39 ± 0.26 vs 0.39 ± 0.19 mmol/d, p = 0.277). Calculated Psf (probability of stone formation) values were only predictive for the risk of calcium phosphate stones. A diet low in sodium and calcium in recurrent calcium oxalate stone formers resulted in a significant reduction of urinary calcium excretion, but no change in urine volume. In this population with apparently low intake of dairy products, calcium restriction does not

Stone formation in the Middle Eastern Gulf States: A review.

PubMed

Robertson, William G

2012-09-01

To review the possible causes of the high incidence of urolithiasis in the oil-rich Gulf States. Data were extracted from published reports on the incidence of urolithiasis, affluence and diet in the Gulf States, various Western countries and China. There are strong relationships: (a) between the life-expectancy of stones in men and the Gross National Income (GNI) per capita of these countries; and (b) between the daily consumption of animal protein and GNI per capita. Together these data suggest that the occurrence of stones is proportional to the intake of animal protein, although they also indicate that there are additional factors that further increase the risk of urolithiasis in the populations of the Gulf. The consumption of oxalate in the Gulf is three times higher and that of calcium a half of what it is in Western countries. Thus, the average oxalate/calcium ratio in the intestines of the Gulf populations is five to six times higher than that in Western populations, leading to enteric hyperoxaluria and an increased risk of calcium-oxalate stone formation. The risk is further accentuated by the lower urine volumes, due to the hot, dry climate of the region, and lower excretions of citrate, from the highly acidic urine resulting from the high intake of animal protein. There is a high incidence of uric acid-containing stones from the acidic urine and the hyperuricosuria caused by the high intake of purine. The high incidence of urolithiasis in the Gulf is due to an adverse combination of dietary and environmental factors.

Effect of different brewing times on soluble oxalate content of loose-packed black teas and tea bags.

PubMed

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

2013-02-01

Because of the postulated role of increased dietary oxalate intake in calcium oxalate stone formation, the effect of different brewing times on soluble oxalate contents of loose-packed black tea and tea bags was studied. The oxalate content of 25 different samples of loose-packed black teas after brewing at 5, 10, 15, 30, and 60 min and of ten brands of tea bags after infusion for 1, 2, 3, 4, and 5 min was measured by enzymatic assay. The oxalate concentration resulting from different brewing times ranged from 4.3 to 6.2 mg/240 ml for loose-packed black teas and from 2.7 to 4.8 mg/240 ml for tea bags. There was a stepwise increase in oxalate concentration associated with increased brewing times.

Defining and systematic analyses of aggregation indices to evaluate degree of calcium oxalate crystal aggregation

NASA Astrophysics Data System (ADS)

Chaiyarit, Sakdithep; Thongboonkerd, Visith

2017-12-01

Crystal aggregation is one of the most crucial steps in kidney stone pathogenesis. However, previous studies of crystal aggregation were rarely done and quantitative analysis of aggregation degree was handicapped by a lack of the standard measurement. We thus performed an in vitro assay to generate aggregation of calcium oxalate monohydrate (COM) crystals with various concentrations (25-800 µg/ml) in saturated aggregation buffer. The crystal aggregates were analyzed by microscopic examination, UV-visible spectrophotometry, and GraphPad Prism6 software to define a total of 12 aggregation indices (including number of aggregates, aggregated mass index, optical density, aggregation coefficient, span, number of aggregates at plateau time-point, aggregated area index, aggregated diameter index, aggregated symmetry index, time constant, half-life, and rate constant). The data showed linear correlation between crystal concentration and almost all of these indices, except only for rate constant. Among these, number of aggregates provided the greatest regression coefficient (r=0.997; p<0.001), whereas the equally second rank included aggregated mass index and optical density (r=0.993; p<0.001 and r=‑0.993; p<0.001, respectively) and the equally forth were aggregation coefficient and span (r=0.991; p<0.001 for both). These five indices are thus recommended as the most appropriate indices for quantitative analysis of COM crystal aggregation in vitro.

Evaluation of biochemical urinary stone composition and its relationship to tap water hardness in Qom province, central Iran

PubMed Central

Moslemi, Mohammad Kazem; Saghafi, Hossein; Joorabchin, Seyed Mohammad Amin

2011-01-01

Purpose The aim of this study was to evaluate the biochemical stone composition in general population of Qom province, central Iran, and its relationship with high tap water hardness. Materials and methods In a prospective study, from March 2008 to July 2011, biochemical analysis of urinary stones in patients living in Qom province for at least 5 years was performed. Stones were retrieved by spontaneous passage, endoscopic or open surgery, and after extracorporeal shockwave lithotripsy. Demographic findings and the drinking water supply of patients were evaluated and compared with biochemical stone analysis. Results Stone analysis was performed in 255 patients. The most dominant composition of urinary stones was calcium oxalate (73%), followed by uric acid (24%), ammonium urate (2%), and cystine (1%). The peak incidence of urinary stone was in patients in their forties. Overall male to female ratio was 4.93:1. Conclusion The dominant stone composition in inhabitants of central Iran, where tap water hardness is high, was calcium oxalate stones. On the basis of this study, biochemical urinary stone composition of Qom does not differ from other regions of Iran with lower water hardness. PMID:22163171

Assessing applicants to the NASA flight program for their renal stone-forming potential

NASA Technical Reports Server (NTRS)

Pak, Charles Y. C.; Hill, Kathy; Cintron, Nitza M.; Huntoon, Carolyn

1989-01-01

Because spaceflight can provoke the formation of kidney stones, 24-hour urine samples for 104 male applicants were analyzed for stone-forming risk factors prior to their selection into the NASA astronaut-mission specialist corps. A high level of supersaturation (with either calcium oxalate, brushite, or monosodium urate) was noted in these applicants which predisposes them to the crystallization of stone-forming calcium salts. It is suggested that most of the abnormal stone risk factors found were environmental, rather than metabolic, in origin.

Evaluation and medical management of kidney stones in children.

PubMed

Tasian, Gregory E; Copelovitch, Lawrence

2014-11-01

We review the current literature on the diagnostic evaluation and dietary and pharmacological management of children with nephrolithiasis. We searched MEDLINE(®), Embase(®) and the Cochrane Library from their inceptions to March 2014 for published articles in English on kidney stones and therapy in children 0 to 18 years old. Based on review of the titles and abstracts, 110 of the 1,014 articles (11%) were potentially relevant to the diagnostic evaluation and medical management of nephrolithiasis in children. We summarized this literature and drew on studies performed in adult populations to augment areas in which no studies of sufficient quality have been performed in children, and to highlight areas in need of research. During the last 25 years the incidence of nephrolithiasis in children has increased by approximately 6% to 10% annually and is now 50 per 100,000 adolescents. Kidney stones that form during childhood have a similar composition to those that form in adulthood. Approximately 75% to 80% of stones are composed of predominantly calcium oxalate, 5% to 10% are predominantly calcium phosphate, 10% to 20% are struvite and 5% are pure uric acid. The recurrence rate of nephrolithiasis in patients with stones that form during childhood is poorly defined. Ultrasound should be used as the initial imaging study to evaluate children with suspected nephrolithiasis, with noncontrast computerized tomography reserved for those in whom ultrasound is nondiagnostic and the suspicion of nephrolithiasis remains high. Current treatment strategies for children with kidney stone disease are based largely on extrapolation of studies performed in adult stone formers and single institution cohort or case series studies of children. Tamsulosin likely increases the spontaneous passage of ureteral stones in children. Increased water intake and reduction of salt consumption should be recommended for all children with a history of kidney stones. Potassium citrate is a

Comparison of tissue injury from focused ultrasonic propulsion of kidney stones versus extracorporeal shock wave lithotripsy.

PubMed

Connors, Bret A; Evan, Andrew P; Blomgren, Philip M; Hsi, Ryan S; Harper, Jonathan D; Sorensen, Mathew D; Wang, Yak-Nam; Simon, Julianna C; Paun, Marla; Starr, Frank; Cunitz, Bryan W; Bailey, Michael R; Lingeman, James E

2014-01-01

Focused ultrasonic propulsion is a new noninvasive technique designed to move kidney stones and stone fragments out of the urinary collecting system. However, to our knowledge the extent of tissue injury associated with this technique is not known. We quantitated the amount of tissue injury produced by focused ultrasonic propulsion under simulated clinical treatment conditions and under conditions of higher power or continuous duty cycles. We compared those results to extracorporeal shock wave lithotripsy injury. A human calcium oxalate monohydrate stone and/or nickel beads were implanted by ureteroscopy in 3 kidneys of live pigs weighing 45 to 55 kg and repositioned using focused ultrasonic propulsion. Additional pig kidneys were exposed to extracorporeal shock wave lithotripsy level pulse intensity or continuous ultrasound exposure 10 minutes in duration using an ultrasound probe transcutaneously or on the kidney. These kidneys were compared to 6 treated with an unmodified Dornier HM3 lithotripter (Dornier Medical Systems, Kennesaw, Georgia) using 2,400 shocks at 120 shock waves per minute and 24 kV. Histological analysis was performed to assess the volume of hemorrhagic tissue injury created by each technique according to the percent of functional renal volume. Extracorporeal shock wave lithotripsy produced a mean ± SEM lesion of 1.56% ± 0.45% of functional renal volume. Ultrasonic propulsion produced no detectable lesion with simulated clinical treatment. A lesion of 0.46% ± 0.37% or 1.15% ± 0.49% of functional renal volume was produced when excessive treatment parameters were used with the ultrasound probe placed on the kidney. Focused ultrasonic propulsion produced no detectable morphological injury to the renal parenchyma when using clinical treatment parameters but produced injury comparable in size to that of extracorporeal shock wave lithotripsy when using excessive treatment parameters. Copyright © 2014 American Urological Association Education and

Acoustic and mechanical properties of renal calculi: implications in shock wave lithotripsy.

PubMed

Chuong, C J; Zhong, P; Preminger, G M

1993-12-01

The acoustic and mechanical properties of renal calculi dictate how a stone interacts with the mechanical forces produced by shock wave lithotripsy; thus, these properties are directly related to the success of the treatment. Using an ultrasound pulse transmission technique, we measured both longitudinal and transverse (or shear) wave propagation speeds in nine groups of renal calculi with different chemical compositions. We also measured stone density using a pycnometer based on Archimedes' principle. From these measurements, we calculated wave impedance and dynamic mechanical properties of the renal stones. Calcium oxalate monohydrate and cystine stones had higher longitudinal and transverse wave speeds, wave impedances, and dynamic moduli (bulk modulus, Young's modulus, and shear modulus), suggesting that these stones are more difficult to fragment. Phosphate stones (carbonate apatite and magnesium ammonium phosphate hydrogen) were found to have lower values of these properties, suggesting they are more amenable to shock wave fragmentation. These data provide a physical explanation for the significant differences in stone fragility observed clinically.

Coupled CFD-PBE Predictions of Renal Stone Size Distributions in the Nephron in Microgravity

NASA Technical Reports Server (NTRS)

Kassemi, Mohammad; Griffin, Elise; Thompson, David

2016-01-01

In this paper, a deterministic model is developed to assess the risk of critical renal stone formation for astronauts during space travel. A Population Balance Equation (PBE) model is used to compute the size distribution of a population of nucleating, growing and agglomerating renal calculi as they are transported through different sections of the nephron. The PBE model is coupled to a Computational Fluid Dynamics (CFD) model that solves for steady state flow of urine and transport of renal calculi along with the concentrations of ionic species, calcium and oxalate, in the nephron using an Eulerian two-phase mathematical framework. Parametric simulation are performed to study stone size enhancement and steady state volume fraction distributions in the four main sections of the nephron under weightlessness conditions. Contribution of agglomeration to the stone size distribution and effect of wall friction on the stone volume fraction distributions are carefully examined. Case studies using measured astronaut urinary calcium and oxalate concentrations in microgravity as input indicate that under nominal conditions the largest stone sizes developed in Space will be still considerably below the critical range for problematic stone development. However, results also indicate that the highest stone volume fraction occurs next to the tubule and duct walls. This suggests that there is an increased potential for wall adhesion with the possibility of evolution towards critical stone sizes.

Autophagy inhibition attenuates hyperoxaluria-induced renal tubular oxidative injury and calcium oxalate crystal depositions in the rat kidney.

PubMed

Duan, Xiaolu; Kong, Zhenzhen; Mai, Xin; Lan, Yu; Liu, Yang; Yang, Zhou; Zhao, Zhijian; Deng, Tuo; Zeng, Tao; Cai, Chao; Li, Shujue; Zhong, Wen; Wu, Wenqi; Zeng, Guohua

2018-06-01

Hyperoxaluria-induced oxidative injury of renal tubular epithelial cell is a casual and essential factor in kidney calcium oxalate (CaOx) stone formation. Autophagy has been shown to be critical for the regulation of oxidative stress-induced renal tubular injury; however, little is known about its role in kidney CaOx stone formation. In the present study, we found that the autophagy antagonist chloroquine could significantly attenuate oxalate-induced autophagy activation, oxidative injury and mitochondrial damage of renal tubular cells in vitro and in vivo, as well as hyperoxaluria-induced CaOx crystals depositions in rat kidney, whereas the autophagy agonist rapamycin exerted contrasting effects. In addition, oxalate-induced p38 phosphorylation was significantly attenuated by chloroquine pretreatment but was markedly enhanced by rapamycin pretreatment, whereas the protective effect of chloroquine on rat renal tubular cell oxidative injury was partly reversed by a p38 protein kinase activator anisomycin. Furthermore, the knockdown of Beclin1 represented similar effects to chloroquine on oxalate-induced cell oxidative injury and p38 phosphorylation in vitro. Taken together, our results revealed that autophagy inhibition could attenuate oxalate-induced oxidative injury of renal tubular cell and CaOx crystal depositions in the rat kidney via, at least in part, inhibiting the activation of p38 signaling pathway, thus representing a novel role of autophagy in the regulation of oxalate-induced renal oxidative injury and CaOx crystal depositions for the first time. Copyright © 2018. Published by Elsevier B.V.

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 (λ = 2120 nm) was operated with standard parameters of 600 mJ, 350 μs, 6 Hz, and 270-μm-core optical fiber. TFL (λ = 1908 nm) was operated with 35 mJ, 500 μs, 150-500 Hz, and 100-μm-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.

Factors affecting calcium oxalate dihydrate fragmented calculi regrowth

PubMed Central

Costa-Bauzá, A; Perelló, J; Isern, B; Sanchis, P; Grases, F

2006-01-01

Background The use of extracorporeal shock wave lithotripsy (ESWL) to treat calcium oxalate dihydrate (COD) renal calculi gives excellent fragmentation results. However, the retention of post-ESWL fragments within the kidney remains an important health problem. This study examined the effect of various urinary conditions and crystallization inhibitors on the regrowth of spontaneously-passed post-ESWL COD calculi fragments. Methods Post-ESWL COD calculi fragments were incubated in chambers containing synthetic urine varying in pH and calcium concentration: pH = 5.5 normocalciuria (3.75 mM), pH = 5.5 hypercalciuria (6.25 mM), pH = 6.5 normocalciuria (3.75 mM) or pH = 6.5 hypercalciuria (6.25 mM). Fragment growth was evaluated by measuring increases in weight. Fragment growth was standardized by calculating the relative mass increase. Results Calcium oxalate monohydrate (COM) crystals formed on COD renal calculi fragments under all conditions. Under pH = 5.5 normocalciuria conditions, only COM crystals formed (growth rate = 0.22 ± 0.04 μg/mg·h). Under pH = 5.5 hypercalciuria and under pH = 6.5 normocalciuria conditions, COM crystals and a small number of new COD crystals formed (growth rate = 0.32 ± 0.03 μg/mg·h and 0.35 ± 0.05 μg/mg·h, respectively). Under pH = 6.5 hypercalciuria conditions, large amounts of COD, COM, hydroxyapatite and brushite crystals formed (growth rate = 3.87 ± 0. 34 μg/mg·h). A study of three crystallization inhibitors demonstrated that phytate completely inhibited fragment growth (2.27 μM at pH = 5.5 and 4.55 μM at pH = 6.5, both under hypercalciuria conditions), while 69.0 μM pyrophosphate caused an 87% reduction in mass under pH = 6.5 hypercalciuria conditions. In contrast, 5.29 mM citrate did not inhibit fragment mass increase under pH = 6.5 hypercalciuria conditions. Conclusion The growth rate of COD calculi fragments under pH = 6.5 hypercalciuria conditions was approximately ten times that observed under the other three

Oxalate content of different drinkable dilutions of tea infusions after different brewing times.

PubMed

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

2012-01-01

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. 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. 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). 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.

Stone former urine proteome demonstrates a cationic shift in protein distribution compared to normal.

PubMed

Kolbach-Mandel, Ann M; Mandel, Neil S; Hoffmann, Brian R; Kleinman, Jack G; Wesson, Jeffrey A

2017-08-01

Many urine proteins are found in calcium oxalate stones, yet decades of research have failed to define the role of urine proteins in stone formation. This urine proteomic study compares the relative amounts of abundant urine proteins between idiopathic calcium oxalate stone forming and non-stone forming (normal) cohorts to identify differences that might correlate with disease. Random mid-morning urine samples were collected following informed consent from 25 stone formers and 14 normal individuals. Proteins were isolated from urine using ultrafiltration. Urine proteomes for each sample were characterized using label-free spectral counting mass spectrometry, so that urine protein relative abundances could be compared between the two populations. A total of 407 unique proteins were identified with the 38 predominant proteins accounting for >82% of all sample spectral counts. The most highly abundant proteins were equivalent in stone formers and normals, though significant differences were observed in a few moderate abundance proteins (immunoglobulins, transferrin, and epidermal growth factor), accounting for 13 and 10% of the spectral counts, respectively. These proteins contributed to a cationic shift in protein distribution in stone formers compared to normals (22% vs. 18%, p = 0.04). Our data showing only small differences in moderate abundance proteins suggest that no single protein controls stone formation. Observed increases in immunoglobulins and transferrin suggest increased inflammatory activity in stone formers, but cannot distinguish cause from effect in stone formation. The observed cationic shift in protein distribution would diminish protein charge stabilization, which could lead to protein aggregation and increased risk for crystal aggregation.

Metabolic stone composition in Egyptian children.

PubMed

Aggour, Ashraf; Ziada, Ali M; AbdelHamid, Ahmad Z; AbdelRahman, Sherif; Morsi, Ahmad

2009-04-01

The composition of urinary stones in children depends on socioeconomic conditions, geography and dietary habits. Pediatric urolithiasis remains endemic in developing countries. The aim of this study was to analyze stone composition in an Egyptian patient population. We analyzed prospectively urinary stones from 100 consecutive children (73 males, 27 females), aged 14 months to 12 years. The stones were located in the upper urinary tract in 78%, lower urinary tract in 19% and both in 3%. Male patients had more lower urinary tract stones. On presentation 67% had flank pain and 37% had hematuria. Stones were treated by open surgery in 69% of patients, shockwave lithotripsy in 20% and endoscopic extraction in 13%. The components of the upper urinary tract calculi were calcium oxalate (47%), ammonium acid urate (26%) and calcium carbonate (21%), whereas the main components of the lower urinary tract calculi were ammonium acid urate (27.2%), struvite (27.2%) and calcium carbonate (22.7%). Urinary tract infection was involved in the development of one third of the stones. Endemic stones were present in 17% of patients, and stones of metabolic origin in 15%. The etiology of stone formation remained unknown in one third of patients. The epidemiological profile of urinary stones in Egyptian children can now be considered intermediate between developing countries where dietary deficiencies are the main causes and developed countries where infectious and metabolic calculi are observed.

INACCURATE REPORTING OF MINERAL COMPOSITION BY COMMERCIAL STONE ANALYSIS LABORATORIES: IMPLICATIONS FOR INFECTION AND METABOLIC STONES

PubMed Central

Krambeck, Amy E.; Khan, Naseem F.; Jackson, Molly E.; Lingeman, James E.; McAteer, James A; Williams, James C.

2011-01-01

INTRODUCTION The goal of this study was to determine the accuracy of stone composition analysis by commercial laboratories. METHODS 25 human renal stones with infrared spectroscopy (IR) determined compositions were fragmented into aliquots and studied with micro-computed tomography (CT) to ensure fragment similarity. Representative fragments of each stone were submitted to 5 commercial stone laboratories for blinded analysis. RESULTS All laboratories agreed on composition for 6 pure stones. Of 4 stones known to contain struvite, only 2(50%) were identified as struvite by all laboratories. Struvite was reported as a component by some laboratories for 4 stones previously determined not to contain struvite. Overall, there was disagreement regarding struvite in 6(24%) stones. For 9 calcium oxalate (CaOx) stones, all laboratories reported some mixture of CaOx, but the quantities of subtypes differed significantly among laboratories. In 6 apatite containing stones, apatite was missed by the laboratories in 20% of the samples. None of the laboratories identified atazanavir in a stone containing that antiviral drug. One laboratory reported protein in every sample, while all others reported it in only 1 sample. Nomenclature for apatite differed among laboratories, with one reporting apatite as carbonate apatite (CA) and never hydroxyapatite (HA), another never reporting CA and always reporting HA, and a third reporting CA as apatite with calcium carbonate. CONCLUSIONS Commercial laboratories reliably recognize pure calculi; however, variability in reporting of mixed calculi suggests a problem with accuracy of stone analysis results. Furthermore, there is a lack of standard nomenclature used by laboratories. PMID:20728108

Net Intestinal Transport of Oxalate Reflects Passive Absorption and SLC26A6-mediated Secretion

PubMed Central

Knauf, Felix; Ko, Narae; Jiang, Zhirong; Robertson, William G.; Van Itallie, Christina M.; Anderson, James M.

2011-01-01

Mice lacking the oxalate transporter SLC26A6 develop hyperoxalemia, hyperoxaluria, and calcium-oxalate stones as a result of a defect in intestinal oxalate secretion, but what accounts for the absorptive oxalate flux remains unknown. We measured transepithelial absorption of [14C]oxalate simultaneously with the flux of [3H]mannitol, a marker of the paracellular pathway, across intestine from wild-type and Slc26a6-null mice. We used the anion transport inhibitor DIDS to investigate other members of the SLC26 family that may mediate transcellular oxalate absorption. Absorptive flux of oxalate in duodenum was similar to mannitol, insensitive to DIDS, and nonsaturable, indicating that it is predominantly passive and paracellular. In contrast, in wild-type mice, secretory flux of oxalate in duodenum exceeded that of mannitol, was sensitive to DIDS, and saturable, indicating transcellular secretion of oxalate. In Slc26a6-null mice, secretory flux of oxalate was similar to mannitol, and no net flux of oxalate occurred. Absorptive fluxes of both oxalate and mannitol varied in parallel in different segments of small and large intestine. In epithelial cell lines, modulation of the charge selectivity of the claudin-based pore pathway did not affect oxalate permeability, but knockdown of the tight-junction protein ZO-1 enhanced permeability to oxalate and mannitol in parallel. Moreover, formation of soluble complexes with cations did not affect oxalate absorption. In conclusion, absorptive oxalate flux occurs through the paracellular “leak” pathway, and net absorption of dietary oxalate depends on the relative balance between absorption and SLC26A6-dependent transcellular secretion. PMID:22021714

Assessment of kidney stone and prevalence of its chemical compositions.

PubMed

Pandeya, A; Prajapati, R; Panta, P; Regmi, A

2010-09-01

Kidney stone analysis is the test done on the stone which cause problems when they block the flow of urine through or out of the kidneys. The stones cause severe pain and are also associated with morbidity and renal damage. There is also no clear understanding on the relative metabolic composition of renal calculi. Hence, the study is aimed to find out the chemical composition of it which can guide treatment and give information that may prevent more stones from forming. The study was carried out on the stones that had been sent to the department of Biochemistry (n = 99; M = 61; F = 38; Mean age: 33.6 +/- 14.4 years) Approximately 98.9% of stones were composed of oxalate, 95.9% of Calcium, 85.8% of phosphate, 62.6% of Urate, 46.4% of Ammonium and very few percentages of Carbonate.

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.

Effect of Soda Consumption on Urinary Stone Risk Parameters

PubMed Central

Holmes, Ross P.; Knight, John; Easter, Linda; Pais, Vernon; Assimos, Dean G.

2009-01-01

Abstract Background and Purpose Fluid consumption has been demonstrated to influence kidney stone formation. Studies have shown that consumption of cola may be a risk factor for stone disease, while fluids containing citric acid may attenuate stone activity. Diet was not always controlled in these investigations, however. We undertook a study to determine the impact of three different fluids on urinary stone risk factors. Subjects and Methods Six healthy nonstone-forming adults were placed on a standardized metabolic diet and consumed three different types of fluid during three 5-day periods. There was a 2-day washout between each sequence. The three fluids administered during these periods were Le Bleu® water, caffeine-free Diet Coke,® and Fresca® (citrate containing). These two soda preparations were chosen to prevent the known increase in calcium excretion promoted by carbohydrates and caffeine. Twenty-four hour urine specimens were collected on days 4 and 5 of each sequence. The following urinary parameters were measured: Volume, calcium, oxalate, creatinine, uric acid, citrate, sodium, magnesium, phosphorus, sulfate, urea nitrogen, pH, and supersaturation indices. A paired t test was used for statistical analysis. Results Urinary volumes were significantly higher and supersaturation of calcium oxalate significantly lower compared with a self-selected dietary regimen. A decrease in uric acid was also seen in the Fresca cohort. There were no statistically significant differences for any of the urinary parameters. Conclusion There is no increased risk or benefit to consuming Fresca or caffeine-free Diet Coke compared with Le Bleu bottled water with respect to stone formation. PMID:19275488

Effect of soda consumption on urinary stone risk parameters.

PubMed

Passman, Corey M; Holmes, Ross P; Knight, John; Easter, Linda; Pais, Vernon; Assimos, Dean G

2009-03-01

Fluid consumption has been demonstrated to influence kidney stone formation. Studies have shown that consumption of cola may be a risk factor for stone disease, while fluids containing citric acid may attenuate stone activity. Diet was not always controlled in these investigations, however. We undertook a study to determine the impact of three different fluids on urinary stone risk factors. Six healthy nonstone-forming adults were placed on a standardized metabolic diet and consumed three different types of fluid during three 5-day periods. There was a 2-day washout between each sequence. The three fluids administered during these periods were Le Bleu water, caffeine-free Diet Coke, and Fresca (citrate containing). These two soda preparations were chosen to prevent the known increase in calcium excretion promoted by carbohydrates and caffeine. Twenty-four hour urine specimens were collected on days 4 and 5 of each sequence. The following urinary parameters were measured: Volume, calcium, oxalate, creatinine, uric acid, citrate, sodium, magnesium, phosphorus, sulfate, urea nitrogen, pH, and supersaturation indices. A paired t test was used for statistical analysis. Urinary volumes were significantly higher and supersaturation of calcium oxalate significantly lower compared with a self-selected dietary regimen. A decrease in uric acid was also seen in the Fresca cohort. There were no statistically significant differences for any of the urinary parameters. There is no increased risk or benefit to consuming Fresca or caffeine-free Diet Coke compared with Le Bleu bottled water with respect to stone formation.

[Role of the diet in urinary stone formation and prevalence].

PubMed

Szendrői, Attila; Tordé, Ákos; Vargha, Judit; Bánfi, Gergely; Horváth, András; Horváth, Csaba; Nyirády, Péter

2017-06-01

In Hungary and in the developed countries urinary stones occur more often due to nutritional habits, obesity and sedentary lifestyle beside the endocrine and metabolic causes. In the daily urological and family doctor practice prevention should have an important role. Prevention is based not only on body weight control, physical exercise and medical treatment, but on proper diet as well. The nutritional components can change the consistence of urine, causing supersaturation, which is essential in stone formation. Specific nutritional components can either prevent stone formation (increased fluid intake, citrate, magnesium, fruits and vegetables) or either increase stone formation (decreased fluid intake, proteins, carbohydrates, oxalate, salt, increased calcium intake, ascorbic-acid etc). We summarized evidence-based practical dietary suggestions on the primary and secondary prevention of urinary stones. Orv Hetil. 2017; 158(22): 851-855.

Citrate salts for preventing and treating calcium containing kidney stones in adults.

PubMed

Phillips, Rebecca; Hanchanale, Vishwanath S; Myatt, Andy; Somani, Bhaskar; Nabi, Ghulam; Biyani, C Shekhar

2015-10-06

Kidney stones affect people worldwide and have a high rate of recurrence even with treatment. Recurrences are particularly prevalent in people with low urinary citrate levels. These people have a higher incidence of calcium phosphate and calcium oxalate stones. Oral citrate therapy increases the urinary citrate levels, which in turn binds with calcium and inhibits the crystallisation thus reduces stone formation. Despite the widespread use of oral citrate therapy for prevention and treatment of calcium oxalate stones, the evidence to support its clinical efficacy remains uncertain. The objective of this review was to determine the efficacy and adverse events associated with citrate salts for the treatment and prevention of calcium containing kidney stones. We searched the Cochrane Kidney and Transplant Specialised Register to 29 July 2015 through contact with the Trials' Search Co-ordinator using search terms relevant to this review. We included randomised controlled trials (RCTs) that assessed the efficacy and adverse events associated with citrate salts for the treatment and prevention of calcium containing kidney stones in adults treated for a minimum of six months. Two authors assessed studies for inclusion in this review. Data were extracted according to predetermined criteria. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes. We included seven studies that included a total of 477 participants, most of whom had oxalate stones. Of these, three studies (247 participants) compared potassium citrate with placebo or no intervention; three (166 participants) compared potassium-sodium citrate with no intervention; and one (64 participants) compared potassium-magnesium citrate with placebo. Overall, quality of the reporting of the included studies was considered moderate to

The effects of intracrystalline and surface-bound proteins on the attachment of calcium oxalate monohydrate crystals to renal cells in undiluted human urine

PubMed Central

Grover, Phulwinder K.; Thurgood, Lauren A.; Wang, Tingting; Ryall, Rosemary L.

2010-01-01

Objective To compare the binding to Madin-Darby canine kidney (MDCK)-II cells of: (i) inorganic calcium oxalate monohydrate (iCOM) crystals and COM crystals precipitated from urine containing different concentrations of protein; and (ii) urinary COM crystals containing intracrystalline and intracrystalline + surface-bound protein. Materials and methods Urinary COM crystals were generated in sieved (sCOM), centrifuged and filtered (cfCOM), and ultrafiltered (ufCOM) portions of a pooled human urine and their adhesion to MDCK-II cells was compared using six different ultrafiltered urine samples as the binding medium. Crystal matrix extract (CME) was prepared by demineralizing calcium oxalate crystals precipitated from human urine and used to prepare COM crystals with intracrystalline, and intracrystalline + surface-bound CME at protein concentrations of 0, 0.05, 0.1, 0.5 and 5.0 mg/L. The amount of protein associated with the crystals was qualitatively assessed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting, using prothrombin fragment 1 (PTF1) as a marker. Protein concentration was determined in sieved, centrifuged and filtered, and ultrafiltered fractions of 10 additional urine samples. Results The median crystal attachment in the six urine types decreased in the order iCOM > ufCOM > cfCOM = sCOM, in inverse proportion to the concentration of protein in the solution or urine from which they were precipitated. sCOM and cfCOM crystals bound ≈□ 23% less than iCOM crystals. The attachment of COM crystals generated in the presence of increasing concentrations of CME proteins was unaffected up to a concentration of 5 mg/L, but binding of crystals containing the same concentrations of intracrystalline + surface-bound proteins decreased proportionally at protein concentrations from 0 to 5.0 mg/L. Conclusion Inorganic COM crystals bind significantly more strongly to MDCK-II cells than urinary crystals precipitated from sieved

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

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. Copyright © 2016 the American Physiological Society.

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

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

The increased risk of urinary stone disease in betel quid chewers.

PubMed

Allen, Siân E; Singh, Sadmeet; Robertson, William G

2006-08-01

The chewing of betel quid is a common practice in many countries of the world, particularly in Southeast Asia. The quid consists of a preparation of areca nut, betel leaf and calcium hydroxide "lime" paste ("chuna"). For the first time, we present a study that links its use to urinary stone disease. Eight patients (seven male and one female) who presented to our Stone Unit with recurrent urinary stones were included in the study. All were from the Indian subcontinent and were found to regularly chew betel. The patients underwent metabolic screening including blood, random urine and 24-h urine tests, quantitative chemical analysis of their calculi (where possible) and each completed a 7-day Diet Diary on his/her free, home diet. The study demonstrated a high incidence of hypercalciuria, a tendency to pass an alkaline urine and low urinary citrate excretion among the patients. Together these urinary risk factors increase the probability of developing both calcium phosphate-containing and calcium oxalate-containing stones. In support of this hypothesis, the patients were found to form stones consisting mainly of calcium phosphate but mixed with calcium oxalate. It is concluded that the use of calcium hydroxide "chuna" in the betel quid is the major contributor to the cause of urinary stones in its users. Moreover, the development of urinary lithiasis in such patients may be a precursor to milk-alkali syndrome in those individuals whose chewing habit is more extensive than in the patients in this study and who do not seek to decrease their habit over the long term.

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

A Study of Biomolecules as Growth Modifiers of Calcium Oxalate Crystals

NASA Astrophysics Data System (ADS)

Kwak, Junha John

Crystallization processes are ubiquitous in nature, science, and technology. Controlling crystal growth is pivotal in many industries as material properties and functions can be tailored by tuning crystal habits (e.g. size, shape, phase). In biomineralization, organisms exert excellent control over bottom-up synthesis and assembly of inorganic-organic structures (e.g. bones, teeth, exoskeletons). This is made possible by growth modifiers that range from small molecules to macromolecules, such as proteins. Molecular recognition of the mineral phase allows proteins to function as nucleation templates, matrices, and growth inhibitors or promoters. We are interested in taking a biomimetic approach to control crystallization via biomolecular growth modifiers. We investigated calcium oxalate monohydrate (COM), found in plants and kidney stones, as a model system of crystallization. We studied the effects of four common proteins on COM crystallization: bovine serum albumin (BSA), transferrin, lactoferrin, and lysozyme. Through kinetic studies of COM crystallization, we classified BSA and lysozyme as COM growth inhibitor and promoter respectively. Their inhibition and promotion effects were also evident in the macroscopic crystal habit. Through adsorption and microscopy experiments, we showed that BSA exhibits binding specificity for the apical surfaces of macroscopic COM crystals. Lysozyme, on the other, functions via a non-binding mechanism at the surface to accelerate the growth of the apical surfaces. We also synthesized and studied peptides derived from the protein primary sequences to identify putative domains responsible for these inhibition and promotion effects. Collectively, our study of physiologically relevant biomolecules suggests potential roles of COM modifiers in pathological crystallization and helps to develop guidelines for rational design of biomolecular growth modifiers for applications in crystal engineering.

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.

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

Surface heat shock protein 90 serves as a potential receptor for calcium oxalate crystal on apical membrane of renal tubular epithelial cells.

PubMed

Fong-Ngern, Kedsarin; Sueksakit, Kanyarat; Thongboonkerd, Visith

2016-07-01

Adhesion of calcium oxalate monohydrate (COM) crystals on renal tubular epithelial cells is a crucial step in kidney stone formation. Finding potential crystal receptors on the apical membrane of the cells may lead to a novel approach to prevent kidney stone disease. Our previous study identified a large number of crystal-binding proteins on the apical membrane of MDCK cells. However, their functional role as potential crystal receptors had not been validated. The present study aimed to address the potential role of heat shock protein 90 (HSP90) as a COM crystal receptor. The apical membrane was isolated from polarized MDCK cells by the peeling method and recovered proteins were incubated with COM crystals. Western blot analysis confirmed the presence of HSP90 in the apical membrane and the crystal-bound fraction. Immunofluorescence staining without permeabilization and laser-scanning confocal microscopy confirmed the surface HSP90 expression on the apical membrane of the intact cells. Crystal adhesion assay showed that blocking surface HSP90 by specific anti-HSP90 antibody and knockdown of HSP90 by small interfering RNA (siRNA) dramatically reduced crystal binding on the apical surface of MDCK cells (by approximately 1/2 and 2/3, respectively). Additionally, crystal internalization assay revealed the presence of HSP90 on the membrane of endocytic vesicle containing the internalized COM crystal. Moreover, pretreatment of MDCK cells with anti-HSP90 antibody significantly reduced crystal internalization (by approximately 1/3). Taken together, our data indicate that HSP90 serves as a potential receptor for COM crystals on the apical membrane of renal tubular epithelial cells and is involved in endocytosis/internalization of the crystals into the cells.

Effect of cinnamon and turmeric on urinary oxalate excretion, plasma lipids, and plasma glucose in healthy subjects.

PubMed

Tang, Minghua; Larson-Meyer, D Enette; Liebman, Michael

2008-05-01

High oxalate intake resulting from consuming supplemental doses of cinnamon and turmeric may increase risk of hyperoxaluria, a significant risk factor for urolithiasis. This study assessed urinary oxalate excretion from supplemental doses of cinnamon and turmeric as well as changes in fasting plasma glucose, cholesterol, and triacylglycerol concentrations. Eleven healthy subjects, aged 21-38 y, participated in an 8-wk, randomly assigned, crossover study that involved the ingestion of supplemental doses of cinnamon and turmeric for 4-wk periods that provided 55 mg oxalate/d. Oxalate load tests, which entailed the ingestion of a 63-mg dose of oxalate from the test spices, were performed after each 4-wk experimental period and at the study onset with water only (control treatment). Fasting plasma glucose and lipid concentrations were also assessed at these time points. Compared with the cinnamon and control treatments, turmeric ingestion led to a significantly higher urinary oxalate excretion during the oxalate load tests. There were no significant changes in fasting plasma glucose or lipids in conjunction with the 4-wk periods of either cinnamon or turmeric supplementation. The percentage of oxalate that was water soluble differed markedly between cinnamon (6%) and turmeric (91%), which appeared to be the primary cause of the greater urinary oxalate excretion/oxalate absorption from turmeric. The consumption of supplemental doses of turmeric, but not cinnamon, can significantly increase urinary oxalate levels, thereby increasing risk of kidney stone formation in susceptible individuals.

Vitamin B6 intake and the risk of incident kidney stones.

PubMed

Ferraro, Pietro Manuel; Taylor, Eric N; Gambaro, Giovanni; Curhan, Gary C

2018-06-01

Higher vitamin B6 intake might reduce urinary excretion of oxalate, one of the major determinants of risk for calcium oxalate kidney stones. Previous studies investigating the association between intake of vitamin B6 and risk of stones found conflicting results. We sought to investigate the association in three large prospective cohorts. We prospectively examined the association in the Health Professionals Follow-up Study (HPFS; n = 42,919 men), Nurses' Health Study I (NHS I; n = 60,003 older women), and Nurses' Health Study II (NHS II; n = 90,629 younger women). Hazard ratios (HRs) and 95% confidence intervals (CIs) for incident stones across categories of total vitamin B6 intake (<3.0, 3.0-4.9, 5.0-9.9, 10.0-39.9, ≥40.0 mg/day) were generated with Cox proportional hazards regression models adjusted for potential confounders. During 3,316,846 person-years of follow-up, 6576 incident kidney stones were confirmed. In univariate and multivariate analyses, there was no association between intake of vitamin B6 and incident stones. The HR for stones in the highest category compared with the lowest was 1.05 (95% CI 0.85, 1.30; p value for trend = 0.61) for HPFS, 0.95 (95% CI 0.76, 1.18; p value for trend = 0.42) for NHS I, and 1.06 (95% CI 0.91, 1.24; p value for trend = 0.34) for NHS II. The pooled adjusted HR for the highest category compared with the lowest was 1.03 (95% CI 0.92, 1.15; p value for trend = 0.60). Intake of vitamin B6 is not associated with risk of incident kidney stones.

[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.

Serum concentrations of symmetric dimethylarginine and creatinine in cats with kidney stones.

PubMed

Hall, Jean A; Yerramilli, Maha; Obare, Edward; Li, Jun; Yerramilli, Murthy; Jewell, Dennis E

2017-01-01

Serum concentrations of symmetric dimethylarginine (SDMA) correlate with renal function in cats and SDMA has been shown to be a more reliable and earlier marker for chronic kidney disease (CKD) compared with serum creatinine (Cr). Calcium oxalate uroliths tend to develop in mid-to-older aged cats and kidney stones may cause a reduction in renal function with increased SDMA, but normal serum Cr. The purpose of this retrospective study was to determine if cats with kidney stones had increased serum SDMA concentrations, and whether SDMA increased earlier than serum creatinine concentrations. Cats in the colony with kidney stones diagnosed between August 2010 and December 2015 (n = 43) were compared with healthy geriatric cats (n = 21) without kidney stones. Serum SDMA concentrations were determined by liquid chromatography-mass spectrometry and serum Cr concentrations were determined by enzymatic colorimetry. Cats with kidney stones were diagnosed antemortem by radiographic imaging (n = 12) or by postmortem necropsy (n = 31). Retrospectively, serum SDMA was found to be increased above the upper reference limit in 39 of 43 cats with kidney stones. Serum Cr was increased above the upper reference limit in 18 of 43 cats; 6 of these 18 cats had terminal azotemia only. The mean time that serum SDMA was increased before serum Cr was increased was 26.9 months (range 0 to 60 months). Kidney stones were composed of calcium oxalate in 30 of 34 cats. The lifespan for cats with kidney stones (mean, 12.5 years; range, 6.1 to 18.1 years) was shorter (P < 0.001) than for control cats (mean, 15.2 years; range, 13.0 to 17.2 years), suggesting that non-obstructive kidney stones have an effect on mortality rate or rate of CKD progression. In conclusion, if SDMA concentrations are elevated in mid-to-older aged cats, further imaging studies are warranted to check for the presence of kidney stones.

Serum concentrations of symmetric dimethylarginine and creatinine in cats with kidney stones

PubMed Central

Hall, Jean A.; Yerramilli, Maha; Obare, Edward; Li, Jun; Yerramilli, Murthy; Jewell, Dennis E.

2017-01-01

Serum concentrations of symmetric dimethylarginine (SDMA) correlate with renal function in cats and SDMA has been shown to be a more reliable and earlier marker for chronic kidney disease (CKD) compared with serum creatinine (Cr). Calcium oxalate uroliths tend to develop in mid-to-older aged cats and kidney stones may cause a reduction in renal function with increased SDMA, but normal serum Cr. The purpose of this retrospective study was to determine if cats with kidney stones had increased serum SDMA concentrations, and whether SDMA increased earlier than serum creatinine concentrations. Cats in the colony with kidney stones diagnosed between August 2010 and December 2015 (n = 43) were compared with healthy geriatric cats (n = 21) without kidney stones. Serum SDMA concentrations were determined by liquid chromatography-mass spectrometry and serum Cr concentrations were determined by enzymatic colorimetry. Cats with kidney stones were diagnosed antemortem by radiographic imaging (n = 12) or by postmortem necropsy (n = 31). Retrospectively, serum SDMA was found to be increased above the upper reference limit in 39 of 43 cats with kidney stones. Serum Cr was increased above the upper reference limit in 18 of 43 cats; 6 of these 18 cats had terminal azotemia only. The mean time that serum SDMA was increased before serum Cr was increased was 26.9 months (range 0 to 60 months). Kidney stones were composed of calcium oxalate in 30 of 34 cats. The lifespan for cats with kidney stones (mean, 12.5 years; range, 6.1 to 18.1 years) was shorter (P < 0.001) than for control cats (mean, 15.2 years; range, 13.0 to 17.2 years), suggesting that non-obstructive kidney stones have an effect on mortality rate or rate of CKD progression. In conclusion, if SDMA concentrations are elevated in mid-to-older aged cats, further imaging studies are warranted to check for the presence of kidney stones. PMID:28384169

Bone Genes in the Kidney of Stone Formers

NASA Astrophysics Data System (ADS)

Evan, Andrew P.; Bledsoe, Sharon B.

2008-09-01

Intraoperative papillary biopsies from kidneys of idiopathic-calcium oxalate stone formers (ICSF) have revealed a distinct pattern of mineral deposition in the interstitium of the renal papilla. The earliest sites of these deposits, termed Randall's plaque, are found in the basement membrane of thin loops of Henle and appear to spread into the surrounding interstitium down to the papillary epithelium. Recent studies show kidney stones of ICSF patients grow attached to the renal papilla and at sites of Randall's plaque. Together these observations suggest that plaque formation may be the critical step in stone formation. In order to control plaque formation and thereby reduce future kidney stone development, the mechanism of plaque deposition must be understood. Because the renal papilla has unique anatomical features similar to bone and the fact that the interstitial deposits of ICSF patients are formed of biological apatite, this paper tests the hypothesis that sites of interstitial plaque form as a result of cell-mediated osteoblast-like activity.

Correlation of metabolic syndrome with urinary stone composition.

PubMed

Cho, Sung Tae; Jung, Seung Il; Myung, Soon Chul; Kim, Tae Hyoung

2013-02-01

To determine the correlation between metabolic syndrome and the distribution of stone components in patients with urolithiasis. Between January 2007 and December 2010, renal or ureteral stones were collected from 712 patients (432 males, 280 females) who underwent surgical intervention at three hospitals in South Korea. Metabolic syndrome was defined according to the latest definition of the International Diabetes Federation, using ethnicity- and sex-specific cut-off values for central obesity. Patients were assessed by factors used in metabolic syndrome. All urinary stones were analyzed using infrared spectrophotometry and categorized according to their main component. The patients' mean age was 55.9 years (range 19-93 years). Of the 712 patients, 347 (48.7%; 205 males, 142 females) had a diagnosis of metabolic syndrome. Calcium oxalate (71.5%), uric acid (15.3%), carbonate apatite (8.0%) and struvite (4.1%) calculi were found as the main stone components. Overall, the proportion of uric acid calculi was markedly higher in patients with rather than without metabolic syndrome (19.6 vs 11.2%; P=0.002). However, the proportion of calcium oxalate, carbonate apatite and struvite calculi did not differ between the two groups. The multivariable-adjusted odds ratio for uric acid calculi according to the metabolic syndrome components indicated that the presence of metabolic syndrome was associated with a 93% increased odds ratio of uric acid calculi compared with the absence of metabolic syndrome. Impaired fasting glucose and hypertriglyceridemia were independent risk factors for uric acid calculi. Metabolic syndrome is associated with a significantly increased risk of uric acid calculi development, especially those with impaired fasting glucose and hypertriglyceridemia. © 2012 The Japanese Urological Association.

Kidney stones: Composition, frequency and relation to metabolic diagnosis.

PubMed

Spivacow, Francisco R; Del Valle, Elisa E; Lores, Ernesto; Rey, Paula G

Nephrolithiasis is one of the most frequent urologic diseases. The aim of this paper is to study the composition and frequency of 8854 patient kidney stones and in a subset of them their metabolic risk factors to be related to their type of calculi. Physicochemical and crystallographic methods were used to assess kidney stone composition. In a subset of 715 patients, we performed an ambulatory metabolic protocol with diagnostic purposes. From the total sample 79% of stones were made of calcium salts (oxalate and phosphate), followed by uric acid stones in 16.5%, calcium salts and uric acid in 2%, other salts in 1.9% and cystine in 0.6%. Male to female ratio was almost three times higher in calcium salts and other types of stones, reaching a marked male predominance in uric acid stones, M/F 18.8 /1.0. The major risk factors for calcium stones are idiopathic hypercalciuria, followed by unduly acidic urine pH and hyperuricosuria. In uric acid stones unduly acidic urine pH and less commonly hyperuricosuria are the most frequent biochemical diagnosis. Our results show that analysis of kidney stones composition and the corresponding metabolic diagnosis may provide a scientific basis for the best management and prevention of kidney stone formation, as well as it may help us to study the mechanisms of urine stone formation.

Effect of Kimchi Fermentation on Oxalate Levels in Silver Beet (Beta vulgaris var. cicla)

PubMed Central

Wadamori, Yukiko; Vanhanen, Leo; Savage, Geoffrey P.

2014-01-01

Total, soluble and insoluble oxalates were extracted and analyzed by high performance liquid chromatography (HPLC) following the preparation of kimchi using silver beet (Beta vulgaris var. cicla) stems and leaves. As silver beet contains high oxalate concentrations and consumption of high levels can cause the development of kidney stones in some people, the reduction of oxalate during preparation and fermentation of kimchi was investigated. The silver beet stems and leaves were soaked in a 10% brine solution for 11 h and then washed in cold tap water. The total, soluble and insoluble oxalate contents of the silver beet leaves were reduced by soaking in brine, from 4275.81 ± 165.48 mg/100 g to 3709.49 ± 216.51 mg/100 g fresh weight (FW). Fermenting the kimchi for 5 days at 19.3 ± 0.8 °C in 5 L ceramic jars with a water airtight seal resulted in a mean 38.50% reduction in total oxalate content and a mean 22.86% reduction in soluble oxalates. The total calcium content was essentially the same before and after the fermentation of the kimchi (mean 296.1 mg/100 g FW). The study showed that fermentation of kimchi significantly (p < 0.05) reduced the total oxalate concentration in the initial mix from 609.32 ± 15.69 to 374.71 ± 7.94 mg/100 g FW in the final mix which led to a 72.3% reduction in the amount of calcium bound to insoluble oxalate. PMID:28234318

Plasma oxalic acid and calcium levels in oxalate poisoning

PubMed Central

Zarembski, P. M.; Hodgkinson, A.

1967-01-01

Observations are reported on five cases of suicide or attempted suicide by poisoning with oxalic acid or ethylene glycol. Elevated oxalic acid levels were observed in the plasma, stomach contents, and a number of tissues. Raised oxalic acid levels in plasma were associated with reduced total and ultrafilterable calcium levels. It is suggested that the reduction in plasma total calcium level is due mainly to the deposition of calcium oxalate in the soft tissues, but inhibition of the parathyroid glands may be a contributory factor. Microscopic examination of various tissues indicated that oxalic acid is deposited in the tissues in two forms: (1) crystalline calcium oxalate dihydrate in the kidney and (2) a non-crystalline complex of calcium oxalate and lipid in liver and other tissues. PMID:5602563

Degradation of oxalate in rats implanted with immobilized oxalate oxidase.

PubMed

Raghavan, K G; Tarachand, U

1986-01-20

Accumulation of oxalate leads to hyperoxaluria and calcium oxalate nephrolithiasis in man. Since oxalate is a metabolic end product in mammals, the feasibility of its enzymic degradation has been tested in vivo in rats by administering exogenous oxalate oxidase. Oxalate oxidase, isolated from banana fruit peels, in its native form was found to be non-active at the physiological pH of the recipient animal. However, its functional viability in the recipient animal was ensured by its prior binding with ethylenemaleic anhydride, thus shifting its pH activity curve towards the alkaline range. Rats implanted with dialysis membrane capsules containing such immobilized oxalate oxidase in their peritoneal cavities effectively metabolized intraperitoneally injected [14C]oxalate as well as its precursor [14C]glyoxalate. The implantation of capsules containing coentrapped multienzyme preparations of oxalate oxidase, catalase and peroxidase led to a further degradation of administered [14C]oxalate in rats.

Demography and biochemistry of 2800 patients from a renal stones clinic.

PubMed

Walker, Valerie; Stansbridge, Elizabeth M; Griffin, Damian G

2013-03-01

Because the causes of stones are uncertain, interventions to prevent recurrence have an insecure foundation. Progress depends on careful evaluation of stone formers. A descriptive retrospective database study of 1983 men and 816 women from the Southampton stones clinic from 1990 to March 2007. Anonymized data from the first attendance were analysed using non-parametric statistical tests. Sex ratio (2.43:1), age (median 49 y, 2.5th-97.5th percentiles, 23-77 y men, 20-79 y women), recurrent stone formers (30%) and type of stone were similar to other centres. Women more often had a positive family history (24% versus 19% men), previous urinary infection (31% versus 5%) and structural urinary tract abnormality (14% versus 7%); more men had gout (5% versus 1%) and bladder outlet obstruction (3% versus <1%). Calcium, oxalate and uric acid excretion were increased in 43%, 17% and 22% respectively of men and 31%, 7% and 10% of women. Urinary calcium, oxalate and uric acid correlated significantly, r ranging from 0.149 to 0.311 for 24 h excretion and 0.510 to 0.695 for concentrations per litre. Twenty-two percent of men and 8% of women with normal parathyroid hormone had phosphaturia (excretion of phosphate corrected for glomerular filtration rate (TmPO4/GFR) < 0.70 mmol/L); 6% men and 1.6% women also had low plasma phosphate. Many variables correlated significantly but often weakly with age. Creatinine clearance, pH and (men) TmPO4/GFR decreased from 50 y, urine creatinine, calcium and citrate from 60 y. Risk factors for stones differ between men and women, change with ageing and in some may have a genetic basis. The role of phosphaturia merits further exploration.

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.

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. Copyright © 2015 Elsevier Inc. All rights reserved.

[Correlation between urinary stones and urinary tract infections].

PubMed

Chen, Peilin; Zhang, Liguo; Meng, Bin

2014-05-01

To explore the correlation of urinary stones and urinary tract infections. 300 cases with urinary tract stones received in our hospital from Feb. 2010 to Oct. 2013 were chosen as study samples. Urine routine index, situation of urine positivity and urinary tract infection after surgery were analyzed while, intraoperative cotton swabs were tested after being dipped in liquid near stones. Main components of stones in non-infected and infected stone group were analyzed and compared. Data on urolithiasis was collected. 96 infected stones were found in 300 patients, accounting for 32%, which including 35 cases of E. coli (36.5%), 28 cases of Staphylococcus epidermidis (29.2%), and 15 cases of Proteus mirabilis (15.6%). Numbers of urine abnormalities, urine positivities, positive intraoperative cotton swabs and urinary tract infections in patients in the group with infected stones, were significantly higher than in the group without infected stones and the differences were statistically significant (χ² = 8.203, 73.99, 178.9, 24.26, P < 0.05). The incidence rates of hexahydrate magnesium ammonium phosphate, carbonate apatite and hydroxyapatite stones in the group with infected stones were significantly higher than those in the non-infected-rock group while the incidence rates of calcium oxalate and uric acid stones were found significantly lower than those in the non-infected-stone group, with differences statistically significant (χ² = 167.6, 21.00, 8.586, 73.17, 48.79, P < 0.05). Bacteria could cause urinary tract stones, and infected stones were always associated with urinary tract infections. Bacteria detection in patients with urinary calculi was particularly important to avoid the urinary tract infections.

Effectiveness of Treatment Modalities on Kidney Stone Recurrence.

PubMed

Zisman, Anna L

2017-10-06

Nephrolithiasis is highly prevalent across all demographic groups in the Western world and beyond, and its incidence rates are rising. In addition to the morbidity of the acute event, stone disease often becomes a lifelong problem that requires preventative therapy to diminish ongoing morbidity. Across the majority of stone types, increased fluid intake and targeted dietary modifications are mainstays of therapy. Specific dietary interventions associated with reduced calcium stone risk include adequate dietary calcium intake and restriction of sodium, protein, and oxalate intake, among others. Pharmaceutical therapy may be required if lifestyle changes are insufficient to minimize risk of stone recurrence, and must be targeted to the specific metabolic abnormalities portending risk for a given patient. Therapeutic options for idiopathic calcium stone disease include thiazides, citrate salts, and uric acid-lowering agents. Alkali salts are also the treatment of choice for uric acid stone disease. Management of struvite stone disease is largely surgical, but acetohydroxamic acid is a proven second line therapy. Cystinuria requires lifestyle modifications and may call for thiol-binding agents. Significant heterogeneity of the clinical population with stone disease has previously limited opportunities for large randomized controlled trials. However, as clinical phenotypes and genotypes are increasingly clarified, there are mounting opportunities for targeted randomized controlled trials in stone prevention. In the meantime, the currently available evidence for both lifestyle and pharmacologic interventions is reviewed herein. Copyright © 2017 by the American Society of Nephrology.

Hyperoside protects human kidney‑2 cells against oxidative damage induced by oxalic acid.

PubMed

Chen, Yongliang; Ye, Lihong; Li, Wangjian; Li, Dongzhang; Li, Feng

2018-05-02

The majority of renal calculi (kidney stones) are calcium stones. Oxidative damage to renal tubular epithelial cells induced by reactive oxygen species (ROS) is the predominant cause of calcium oxalate stone formation. Hyperoside (Hyp) is a flavonol glycoside extracted from medicinal plants and appears to exhibit potent antioxidant activity in various cells. The aim of the present study was to investigate the protective effect of Hyp on renal cells exposed to oxidative stress simulated by oxalic acid (OA), and to determine whether the underlying mechanism involves the nuclear factor E2‑related factor2 (Nrf2)‑antioxidative response element signaling pathway. The study determined the indicators of high oxidative stress, including ROS and hydrogen peroxide (H2O2) in human kidney‑2 cells and the results demonstrated that the levels of ROS, as evaluated by flow cytometry, and H2O2 were significantly increased following treatment with OA (5 mmol/l) for 24 h (OA group), compared with those in the untreated control group. The increased activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in these cells explained this observation, as it is a major source of ROS. The results demonstrated that, in the OA group, the adhesion of calcium oxalate crystals and lactate dehydrogenase (LDH) were significantly increased, and MTT assay demonstrated that cell viability was inhibited, compared with the control, which indicated that severe injury of cells was induced by OA. However, when the cells were pre‑treated with Hyp prior to treatment with OA (drug group), the levels of ROS and H2O2, and the activities of NADPH oxidase and LD were increased, and the adhesion of calcium oxalate crystals to cells was reduced, compared with the OA group. Western blot analysis and reverse transcription‑quantitative polymerase chain reaction demonstrated that the protein and mRNA expression levels of Nrf2, heme oxygenase‑1 (HO‑1) and NAD(P)H: quinineoxidoreductase 1

The Roles and Mechanisms of Intestinal Oxalate Transport in Oxalate Homeostasis

PubMed Central

Hatch, Marguerite; Freel, Robert W.

2008-01-01

The mammalian intestine has an important role in the dynamics of oxalate exchange and thereby is significant in the etiology of calcium oxalate nephrolithiasis. Here we review some of the phenomenological observations that have led to the conclusion that anion exchangers (antiporters) are important mediators of secondarily active, net oxalate transport along the intestine (both absorptive and secretory). Understanding the mechanisms of transepithelial oxalate transport has been radically advanced in recent years by the identification of the SLC26 family of anion transporters which has facilitated the identification of specific proteins mediating individual apical or basolateral oxalate transport pathways. Moreover, identification of specific exchangers has underscored their relative importance to oxalate homeostasis as revealed by using knockout mouse models and facilitated studies of oxalate transport regulation in heterologous expression systems. Finally, the significance of oxalate degrading bacteria to oxalate homeostasis is considered from basic and applied perspectives. PMID:18359395

The relationship between serum and urinary Fetuin-A levels and kidney stone formation among kidney stone patients.

PubMed

Mehrsai, Abdolrasoul; Guitynavard, Fateme; Nikoobakht, Mohammad Reza; Gooran, Shahram; Ahmadi, Ayat

2017-01-01

Mineralization inhibitors are required to prevent the precipitation of minerals and inhibit the formation of kidney stones and other ectopic calcifications. In laboratory studies, Fetuin-A as a glycoprotein has inhibited hydroxyapatite precipitation in calcium and phosphate supersaturated solutions; however, information about patients with kidney stones is limited. The aim of this study was to investigate the association of serum and urinary Fetuin-A levels with calcium oxalate kidney stones. In this case-control study, 30 patients with kidney stones and 30 healthy individuals without any history of urolithiasis who were referred to the urology ward of Sina Hospital of Tehran, Iran, in 2015 were entered into the study. All patients underwent computerized tomography scans. After collecting demographic information, serum and urine levels of Fetuin-A and some other calcification inhibitors and promoters, were measured and compared using T-test, Mann-Whitney and logistic regression between the two study groups. Patients with kidney stones, on average, had lower levels of Serum Fetuin-A (1522.27 ±755.39 vs. 1914.64 ±733.76 μg/ml; P = 0.046) as well as lower levels of Urine Fetuin-A (944.62 ±188.5 vs. 1409.68 ±295.26 μg/ml; P <0.001). Multivariate logistic analysis showed that urinary calcium and serum creatinine are the risk factors and Fetuin-A is a urinary protective factor for kidney stones. PFC Our study showed that patients with kidney stones had lower serum and urinary levels of Fetuin-A. In the logistic regression model, urinary Fetuin-A was reported as a protective factor for kidney stones.

Vitamin C with metabolites reduce oxalate levels compared to ascorbic acid: a preliminary and novel clinical urologic finding.

PubMed

Moyad, Mark A; Combs, Maile A; Crowley, David C; Baisley, Joshua E; Sharma, Prachi; Vrablic, Angelica S; Evans, Malkanthi

2009-01-01

The incidence and prevalence of kidney stones are notable and are projected to increase over the next decade. Risk factors for kidney stones abound, but a prominent risk factor is hyperoxaluria, which has numerous etiologies, including vitamin C (ascorbic acid) dietary supplement intake. This randomized, double-blind, crossover study examined the effects of two different vitamin C formulations and found that vitamin C with metabolites (Ester-C) significantly reduced urine oxalate levels compared to ascorbic acid. This is a potential novel finding that requires further clinical evaluation.

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.

Origin of Urinary Oxalate

NASA Astrophysics Data System (ADS)

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

2007-04-01

Urinary oxalate is mostly derived from the absorption of ingested oxalate and endogenous synthesis. The breakdown of vitamin C may also contribute small amounts to the urinary oxalate pool. The amount of oxalate absorbed is influenced by the oxalate content of the diet, the concentrations of divalent cations in the gut, the presence of oxalate-degrading organisms, transport characteristics of the intestinal epithelium, and other factors associated with the intestinal environment. Knowledge of pathways associated with endogenous oxalate synthesis is limited. Urinary oxalate excretion can be modified using strategies that limit dietary oxalate absorption and the ingestion of oxalogenic substrates such as hydroxyproline.

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.

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. 053501...

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... (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. 053501...

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... (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. 053501...

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... (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. 053501...

LITERATURE REVIEW FOR OXALATE OXIDATION PROCESSES AND PLUTONIUM OXALATE SOLUBILITY

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.more » 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.« less

Characteristics of renal papillae in kidney stone formers.

PubMed

Marien, Tracy P; Miller, Nicole L

2016-12-01

The mechanism of kidney stone formation is not well understood. In order to better understand the pathophysiology for specific kidney stone compositions and systemic diseases associated with kidney stones, endoscopic papillary mapping studies with concurrent biopsies have been conducted. This review will summarize the findings of these studies and proposed mechanisms for thirteen disease processes associated with kidney stones. A review of the literature was performed identifying thirteen studies that endoscopically mapped and biopsied renal papillae of different stone formers. These studies characterized renal papillae based on amount of Randall's plaque, Bellini's duct pathology, papillary contour changes, presence of attached stones, pitting, and frequently papillary and cortical biopsies. The groups studied and reviewed here are kidney stone formers who have a history of idiopathic calcium oxalate stone formation, cystinuria, brushite stones, gastric bypass, ileostomy, small bowel resection, primary hyperparathyroidism, distal renal tubular acidosis (dRTA), primary hyperoxaluria, idiopathic calcium phosphate stone formation, medullary sponge kidney (MSK), uric acid stones, and struvite stones. A proposed standardized scoring system for papillary pathology was also reviewed. The series showed various degrees and types of changes to the renal papillae and corresponding histopathologic changes for each type of stone former reviewed. Those with predominantly alone Randall's plaque pathology had less tissue damage versus those with extensive Bellini's duct lesions who had more interstitial fibrosis and cortical pathology. Randall's plaques are associated with stone formers who have low urinary volume, high urinary calcium, and acidic urine and thus are frequently seen in those with brushite stones, primary hyperparathyroidism, small bowel resection, and idiopathic calcium phosphate stone formers. Bellini's duct plugging and pathology is theorized to occur via free

Frequency of metabolic abnormalities in urinary stones patients.

PubMed

Ahmad, Iftikhar; Pansota, Mudassar Saeed; Tariq, Muhammad; Tabassum, Shafqat Ali

2013-11-01

To determine the frequency of metabolic abnormalities in the serum and urine of patients with urinary stones disease. Two hundred patients with either multiple or recurrent urolithiasis diagnosed on ultrasonography and intravenous urography were included in this study. 24 hour urine sample were collected from each patient and sent for PH, specific gravity, Creatinine, uric acid, calcium, phosphate, oxalate, citrate and magnesium. In addition, blood sample of each patient was also sent for serum levels of urea, creatinine, uric acid, phosphate and calcium. Mean age of patients was 38 ± 7.75 years with male to female ratio of 2:1. The main presenting complaint was lumber pain and 82.5% patients were found to have calcium oxalate stones on chemical analysis. Metabolic abnormalities were found in 90.5% patients, whereas there were no metabolic abnormalities in 19 (9.5%) patients. Forty patients (21.5%) only had one metabolic abnormality and 157 (78.5%) patients had multiple metabolic abnormalities. Hyperoxaluria was the most commonly observed metabolic abnormality and was found in 64.5% patients. Other significant metabolic abnormalities were hypercalciuria, Hypercalcemia, hypocitraturia and hyperuricemia. This study concludes that frequency of metabolic abnormalities is very high in patients with urolithiasis and hyperoxaluria, hypercalciuria and hypocitraturia are the most important metabolic abnormalities observed in these patients.

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.

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.

Terahertz spectroscopic investigation of gallic acid and its monohydrate

NASA Astrophysics Data System (ADS)

Zhang, Bo; Li, Shaoping; Wang, Chenyang; Zou, Tao; Pan, Tingting; Zhang, Jianbing; Xu, Zhou; Ren, Guanhua; Zhao, Hongwei

2018-02-01

The low-frequency spectra of gallic acid (GA) and its monohydrate were investigated by terahertz time-domain spectroscopy (THz-TDS) in the range of 0.5 to 4.5 THz. The dehydration process of GA monohydrate was monitored on-line. The kinetic mechanism of the dehydration process was analyzed depending on the THz spectral change at different temperatures. The results indicate that the diffusion of water molecule dominates the speed of the entire dehydration process. Solid-state density functional theory (DFT) calculations of the vibrational modes of both GA and its monohydrate were performed based on their crystalline structures for better interpreting the experimental THz spectra. The results demonstrate that the characterized features of GA mainly originate from the collective vibrations of molecules. And the interactions between GA and water molecules are responsible for THz fingerprint of GA monohydrate. Multi-techniques including differential scanning calorimetry and thermogravimetry (DSC-TG) and powder X-ray diffraction (PXRD) were also carried out to further investigate GA and its monohydrate.

Hygroscopic properties of oxalic acid and atmospherically relevant oxalates

NASA Astrophysics Data System (ADS)

Ma, Qingxin; He, Hong; Liu, Chang

2013-04-01

Oxalic acid and oxalates represent an important fraction of atmospheric organic aerosols, however, little knowledge about the hygroscopic behavior of these particles is known. In this study, the hygroscopic behavior of oxalic acid and atmospherically relevant oxalates (H2C2O4, (NH4)2C2O4, CaC2O4, and FeC2O4) were studied by Raman spectrometry and vapor sorption analyzer. Under ambient relative humidity (RH) of 10-90%, oxalic acid and these oxalates hardly deliquesce and exhibit low hygroscopicity, however, transformation between anhydrous and hydrated particles was observed during the humidifying and dehumidifying processes. During the water adsorption process, conversion of anhydrous H2C2O4, (NH4)2C2O4, CaC2O4, and FeC2O4 to their hydrated particles (i.e., H2C2O4·2H2O, (NH4)2C2O4·H2O, CaC2O4·H2O, and FeC2O4·2H2O) occurred at about 20% RH, 55% RH, 10% RH, and 75% RH, respectively. Uptake of water on hydrated Ca-oxalate and Fe-oxalate particles can be described by a multilayer adsorption isotherm. During the dehumidifying process, dehydration of H2C2O4·2H2O and (NH4)2C2O4·H2O occurred at 5% RH while CaC2O4·H2O and FeC2O4·2H2O did not undergo dehydration. These results implied that hydrated particles represent the most stable state of oxalic acid and oxalates in the atmosphere. In addition, the assignments of Raman shift bands in the range of 1610-1650 cm-1 were discussed according to the hygroscopic behavior measurement results.

[Composition of 359 kidney stones from the East region of Algeria].

PubMed

Bouslama, S; Boutefnouchet, A; Hannache, B; Djemil, T; Kadi, A; Dahdouh, A; Saka, S; Daudon, M

2016-01-01

Determine stones composition of the upper urinary tract in the eastern region of Algeria. Our study focuses on a set of 359 stones of the upper urinary tract collected between January 2007 and December 2012 at hospitals in the eastern region of Algeria and analyzed by Fourier transform infrared spectroscopy. The male/female ratio was only 1.32. Calcium oxalate prevailed in 68.5% of stones and 49.3% of nuclei, mainly as whewellite (51.8% of stones and 37.9% of nuclei vs 16.7% and 11.4% respectively for weddellite). Carbapatite prevailed in 15% of stones and 29.8% of nuclei. The struvite, identified in 11.1% of calculi, prevailed in 3.9% of stones and 3.1% of nuclei. Among purines, uric acid prevailed with frequencies quite close to 8.9% and 7% respectively in the stone and in the nucleus while the ammonium urate prevailed in only 0.3% of stones and 3.3% of nuclei. The cystine frequency was 3.6% in both stone and nucleus. The frequency of stone with umbilication was 26.2%. Whewellite was the main component of umbilicated stones with Randall's plaque. Our results suggest that stones of the urinary tract in the Algerian east region resemble those observed in industrialized countries. Some features such as stones location, the whewellite prevalence, the frequencies of main components in both the stone and the nucleus as well as the formation of stones on renal papilla confirm this trend. 4. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Literature review for oxalate oxidation processes and plutonium oxalate solubility

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.more » 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.« less

Evidence Report: Risk of Renal Stone Formation

NASA Technical Reports Server (NTRS)

Sibonga, Jean D.; Pietrzyk, Robert

2017-01-01

The formation of renal stones poses an in-flight health risk of high severity, not only because of the impact of renal colic on human performance but also because of complications that could potentially lead to crew evacuation, such as hematuria, infection, hydronephrosis, and sepsis. Evidence for risk factors comes from urine analyses of crewmembers, documenting changes to the urinary environment that are conducive to increased saturation of stone-forming salts, which are the driving force for nucleation and growth of a stone nidus. Further, renal stones have been documented in astronauts after return to Earth and in one cosmonaut during flight. Biochemical analysis of urine specimens has provided indication of hypercalciuria and hyperuricemia, reduced urine volumes, and increased urine saturation of calcium oxalate and calcium phosphate. A major contributor to the risk for renal stone formation is bone atrophy with increased turnover of the bone minerals. Dietary and fluid intakes also play major roles in the risk because of the influence on urine pH (more acidic) and on volume (decreased). Historically, specific assessments on urine samples from some Skylab crewmembers indicated that calcium excretion increased early in flight, notable by day 10 of flight, and almost exceeded the upper threshold for normal excretion (300mg/day in males). Other crewmember data documented reduced intake of fluid and reduced intake of potassium, phosphorus, magnesium, and citrate (an inhibitor of calcium stone formation) in the diet. Hence, data from both short-duration and long-duration missions indicate that space travel induces risk factors for renal stone formation that continue to persist after flight; this risk has been documented by reported kidney stones in crewmembers.

Chronic dietary oxalate nephropathy after intensive dietary weight loss regimen

PubMed Central

Khneizer, Gebran; Al-Taee, Ahmad; Mallick, Meher S; Bastani, Bahar

2017-01-01

Background: Hyperoxaluria has been associated with nephrolithiasis as well as acute and chronic kidney disease. We present a case of end stage renal failure caused by excessive dietary oxalate intake in a dietary weight loss regimen. Case Presentation: A 51-year-old Caucasian male with the past medical history of type 2 diabetes mellitus, gout, hypertension and morbid obesity was referred to the primary care clinic after being found pale and easily fatigued. The patient had lost 36 kg over a 7-month period by implementing exercise and intense dietary measures that included 6 meals of spinach, kale, berries, and nuts. Physical examination revealed a blood pressure of 188/93 mm Hg with sunken eyes and dry mucus membranes. Laboratory workup was notable for blood urea nitrogen of 122 mg/dL, creatinine of 12 mg/dL, and estimated glomerular filtration rate (eGFR) of 4.4 mL/min/1.73m2. Patient denied any history of renal disease or renal stones, or taking herbal products, non-steroidal anti-inflammatory drugs, antifreeze (ethylene glycol), or any type of "diet pills." Family history was unremarkable for any renal diseases. After failing intravenous fluid resuscitation, patient was started on maintenance hemodialysis. Abdominal imaging was consistent with chronic renal parenchymal disease with no evidence of nephrolithiasis. Renal biopsy revealed numerous polarized oxalate crystal deposition and diabetic nephropathy class IIA. At this point the patient was instructed to adopt a low oxalate diet. A 24-hour urine collection was remarkable for pH 4.7, citrate <50 mg, and oxalate 46 mg. Importantly, serum oxalate level was undetectable. Repeat renal biopsy 5 months later while patient was still on maintenance hemodialysis revealed persistence of extensive oxalate crystal deposition. Patient has been referred for evaluation for renal transplantation. Conclusions: Clinicians need to maintain a high index of suspicion for dietary hyperoxaluria as a potential etiology for acute or

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.

Urine risk factors in children with calcium kidney stones and their siblings

PubMed Central

Bergsland, Kristin J.; Coe, Fredric L.; White, Mark D.; Erhard, Michael J.; DeFoor, William R.; Mahan, John D.; Schwaderer, Andrew L.; Asplin, John R.

2012-01-01

Calcium nephrolithiasis in children is increasing in prevalence and tends to be recurrent. Although children have a lower incidence of nephrolithiasis than adults, its etiology in children is less well understood; hence treatments targeted for adults may not be optimal in children. To better understand metabolic abnormalities in stone forming children, we compared chemical measurements and the crystallization properties of 24-hour urine collections from 129 stone formers matched to 105 non-stone forming siblings and 183 normal, healthy children with no family history of stones; all aged 6 to 17 years. The principal risk factor for calcium stone formation was hypercalciuria. Stone formers have strikingly higher calcium excretion along with high supersaturation for calcium oxalate and calcium phosphate, and a reduced distance between the upper limit of metastability and supersaturation for calcium phosphate, indicating increased risk of calcium phosphate crystallization. Other differences in urine chemistry that exist between adult stone formers and normal individuals such as hyperoxaluria, hypocitraturia, abnormal urine pH and low urine volume were not found in these children. Hence, hypercalciuria and a reduction in the gap between calcium phosphate upper limit of metastability and supersaturation are crucial determinants of stone risk. This highlights the importance of managing hypercalciuria in children with calcium stones. PMID:22358148

Urine risk factors in children with calcium kidney stones and their siblings.

PubMed

Bergsland, Kristin J; Coe, Fredric L; White, Mark D; Erhard, Michael J; DeFoor, William R; Mahan, John D; Schwaderer, Andrew L; Asplin, John R

2012-06-01

Calcium nephrolithiasis in children is increasing in prevalence and tends to be recurrent. Although children have a lower incidence of nephrolithiasis than adults, its etiology in children is less well understood; hence, treatments targeted for adults may not be optimal in children. To better understand metabolic abnormalities in stone-forming children, we compared chemical measurements and the crystallization properties of 24-h urine collections from 129 stone formers matched to 105 non-stone-forming siblings and 183 normal, healthy children with no family history of stones, all aged 6 to 17 years. The principal risk factor for calcium stone formation was hypercalciuria. Stone formers have strikingly higher calcium excretion along with high supersaturation for calcium oxalate and calcium phosphate, and a reduced distance between the upper limit of metastability and supersaturation for calcium phosphate, indicating increased risk of calcium phosphate crystallization. Other differences in urine chemistry that exist between adult stone formers and normal individuals such as hyperoxaluria, hypocitraturia, abnormal urine pH, and low urine volume were not found in these children. Hence, hypercalciuria and a reduction in the gap between calcium phosphate upper limit of metastability and supersaturation are crucial determinants of stone risk. This highlights the importance of managing hypercalciuria in children with calcium stones.

The production of (14C) oxalate during the metabolism of (14C) carbohydrates in isolated rat hepatocytes.

PubMed

Rofe, A M; James, H M; Bais, R; Edwards, J B; Conyers, R A

1980-04-01

carbohydrates, particularly fructose, contribute to endogenous oxalate production lends support to the hypothesis that a high sucrose consumption contributes to the formation of renal oxalate stones in man.

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 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 sodium...

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 sodium...

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 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 sodium...

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

PubMed

Gulhan, Baris; Turkmen, Kultigin; Aydin, Merve; Gunay, Murat; Cıkman, Aytekin; Kara, Murat

2015-06-01

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. 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. 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. 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.

Biomimetic Randall's plaque as an in vitro model system for studying the role of acidic biopolymers in idiopathic stone formation.

PubMed

Chidambaram, Archana; Rodriguez, Douglas; Khan, Saeed; Gower, Laurie

2015-01-01

Randall's plaque (RP) deposits seem to be consistent among the most common type of kidney stone formers, idiopathic calcium oxalate stone formers. This group forms calcium oxalate renal stones without any systemic symptoms, which contributes to the difficulty of understanding and treating this painful and recurring disease. Thus, the development of an in vitro model system to study idiopathic nephrolithiasis, beginning with RP pathogenesis, can help in identifying how plaques and subsequently stones form. One main theory of RP formation is that calcium phosphate deposits initially form in the basement membrane of the thin loops of Henle, which then fuse and spread into the interstitial tissue, and ultimately make their way across the urothelium, where upon exposure to the urine, the mineralized tissue serves as a nidus for overgrowth with calcium oxalate into a stone. Our group has found that many of the unusual morphologies found in RP and stones, such as concentrically laminated spherulites and mineralized collagenous tissue, can be reproduced in vitro using a polymer-induced liquid precursor (PILP) process, in which acidic polypeptides induce a liquid phase amorphous precursor to the mineral, yielding non-equilibrium crystal morphologies. Given that there are many acidic proteins and polysaccharides present in the renal tissue and urine, we have put forth the hypothesis that the PILP system may be involved in urolithiasis. Therefore, our goal is to develop an in vitro model system of these two stages of composite stone formation to study the role that various acidic macromolecules may play. In our initial experiments presented here, the development of "biomimetic" RP was investigated, which will then serve as a nidus for calcium oxalate overgrowth studies. To mimic the tissue environment, MatriStem(®) (ACell, Inc.), a decellularized porcine urinary bladder matrix was used, because it has both an intact epithelial basement membrane surface and a tunica propria

Further Studies on Oxalic Acid Biosynthesis in Oxalate-accumulating Plants 1

PubMed Central

Nuss, Richard F.; Loewus, Frank A.

1978-01-01

l-Ascorbic acid functions as a precursor of oxalic acid in several oxalate-accumulating plants. The present study extends this observation to include Rumex crispus L. (curly dock), Amaranthus retroflexus L. (red root pigweed), Chenopodium album L. (lamb's-quarters), Beta vulgaris L. (sugar beet), Halogeton glomeratus M. Bieb. (halogeton), and Rheum rhabarbarum L. (rhubarb). Several species with low oxalate content are also examined. When l-[1-14C]ascorbic acid is supplied to young seedlings of R. crispus or H. glomeratus, a major portion of the 14C is released over a 24-hour period as 14CO2 and only a small portion is recovered as [14C]oxalate, unlike cuttings from 2- or 4-month-old plants which retain a large part of the 14C as [14C]oxalic acid and release very little 14CO2. Support for an intermediate role of oxalate in the release of 14CO2 from l-[1-14C]ascorbic acid is seen in the rapid release of 14CO2 by R. crispus and H. glomeratus seedlings labeled with [14C]oxalic acid. The common origin of oxalic acid carbon in the C1 and C2 fragment from l-ascorbic acid is demonstrated by comparison of 14C content of oxalic acid in several oxalate-accumulators after cuttings or seedlings are supplied equal amounts of l-[1-14C]- or l-[UL-14C]ascorbic acid. Theoretically, l-[1-14C]ascorbic acid will produce labeled oxalic acid containing three times as much 14C as l-[UL-14C]ascorbic acid when equal amounts of label are provided. Experimentally, a ratio of 2.7 ± 0.5 is obtained in duplicate experiments with six different species. PMID:16660342

Biochemical profile of stone-forming patients with diabetes mellitus.

PubMed

Pak, Charles Y C; Sakhaee, Khashayar; Moe, Orson; Preminger, Glenn M; Poindexter, John R; Peterson, Roy D; Pietrow, Paul; Ekeruo, Wesley

2003-03-01

To test the hypothesis that stone-forming patients with type II diabetes (DM-II) have a high prevalence of uric acid (UA) stones and present with some of the biochemical features of gouty diathesis (GD). The demographic and initial biochemical data from 59 stone-forming patients with DM-II (serum glucose greater than 126 mg/dL, no insulin therapy, older than 35 years of age) from Dallas, Texas and Durham, North Carolina were retrieved and compared with data from 58 patients with GD and 116 with hyperuricosuric calcium oxalate urolithiasis (HUCU) without DM. UA stones were detected in 33.9% of patients with DM-II compared with 6.2% of stone-forming patients without DM (P <0.001). Despite similar ingestion of alkali, the urinary pH in patients with DM-II and UA stones (n = 20) was low (pH = 5.5), as it is in patients with GD, and was significantly lower than in patients with HUCU. The urinary pH in patients with DM-II and calcium stones (n = 39) was intermediate between that in those with DM-II and UA stones and those with HUCU. However, both DM groups had fractional excretion of urate that was not depressed, as it is in those with GD, and was comparable to the value obtained in those with HUCU. The urinary content of undissociated UA was significantly higher, and the saturation of calcium phosphate (brushite) and sodium urate was significantly lower in those with DM-II and UA stones than in those with HUCU. Stone-forming patients with DM-II have a high prevalence of UA stones. Diabetic patients with UA stones share a key feature of those with GD, namely the passage of unusually acid urine, but not the low fractional excretion of urate.

Frequency of metabolic abnormalities in urinary stones patients

PubMed Central

Ahmad, Iftikhar; Pansota, Mudassar Saeed; Tariq, Muhammad; Tabassum, Shafqat Ali

2013-01-01

Objective: To determine the frequency of metabolic abnormalities in the serum and urine of patients with urinary stones disease. Methods: Two hundred patients with either multiple or recurrent urolithiasis diagnosed on ultrasonography and intravenous urography were included in this study. 24 hour urine sample were collected from each patient and sent for PH, specific gravity, Creatinine, uric acid, calcium, phosphate, oxalate, citrate and magnesium. In addition, blood sample of each patient was also sent for serum levels of urea, creatinine, uric acid, phosphate and calcium. Results: Mean age of patients was 38 ± 7.75 years with male to female ratio of 2:1. The main presenting complaint was lumber pain and 82.5% patients were found to have calcium oxalate stones on chemical analysis. Metabolic abnormalities were found in 90.5% patients, whereas there were no metabolic abnormalities in 19 (9.5%) patients. Forty patients (21.5%) only had one metabolic abnormality and 157 (78.5%) patients had multiple metabolic abnormalities. Hyperoxaluria was the most commonly observed metabolic abnormality and was found in 64.5% patients. Other significant metabolic abnormalities were hypercalciuria, Hypercalcemia, hypocitraturia and hyperuricemia. Conclusion: This study concludes that frequency of metabolic abnormalities is very high in patients with urolithiasis and hyperoxaluria, hypercalciuria and hypocitraturia are the most important metabolic abnormalities observed in these patients. PMID:24550954

Renal stone composition does not affect the outcome of percutaneous nephrolithotomy in children.

PubMed

Kaygısız, Onur; Türegün, Fethi Ahmet; Satar, Nihat; Özen, Ender; Toksöz, Serdar; Doğan, Hasan Serkan; Pişkin, Mehmet Mesut; İzol, Volkan; Sarıkaya, Şaban; Kılıçarslan, Hakan; Çiçek, Tufan; Öztürk, Ahmet; Tekgül, Serdar; Önal, Bülent

2018-05-14

We sought to investigate the association between renal stone composition and percutaneous nephrolithotomy outcomes in pediatric patients and define the characterization of the stone composition. The data of 1157 children who underwent percutaneous nephrolithotomy between 1991 and 2012 were retrieved from the multicenter database of the Turkish Pediatric Urology Society. The study population comprised 359 children (160 girls, 199 boys) with stone analyses. Patients were divided into five groups according to the stone composition [group 1: calcium oxalate; group 2: calcium phosphate; group 3: infection stones (magnesium ammonium phosphate, ammonium urate); group 4: cystine; group 5: uric acid, xanthine stones]. Patient characteristics, perioperative, postoperative, and stone characteristics were compared considering the stone composition. There were no significant differences between the groups concerning age, sex, side involved, preoperative hematocrit levels, and solitary renal unit. Patients with cystine stones were more likely to have a history of stone treatment. Groups 2 and 5 had mostly solitary stones. However, group 3 had staghorn stone more often, and group 4 frequently had multiple stones. Overall stone-free rate (79.4%) was similar among the groups. Although stone composition was related to blood transfusion and prolonged operative and fluoroscopy screening times on univariate analysis, it was not a significant predictor of them on multivariate analysis. Stone composition was not a predictor of outcomes of pediatric percutaneous nephrolithotomy. However, cystine and infection stones, which are larger and filled multiple calyxes due to the nature of stone forming, were more challenging cases that need multiple tracts.

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. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

IL-6 does not predict current urolithiasis in stone formers.

PubMed

Rieder, Jocelyn M; Nisbet, Alan A; Lesser, Timothy; Franke, Ethan I; Brusky, John P; Parekh, Ashish R; Kaptein, John; Bellman, Gary C

2008-10-01

Interleukin-6 (IL-6), an inflammatory marker, has previously been found to be elevated in the urine of patients with urolithiasis. Oxalate and other stone precursors have been shown to increase IL-6 production in proximal tubular epithelial cells in vitro. We examined whether urinary IL-6 could be used as a screening test to determine current urolithiasis in individuals who are known to form urinary stones. Thirty-five adult patients with current urolithiasis demonstrated on imaging were enrolled in the study. Exclusion criteria included disease known to elevate IL-6. Each patient provided a pre-treatment urine specimen and one month after proven to be stone-free an additional urine specimen was obtained. The urinary IL-6/creatinine ratio was determined for both specimens and compared. Ten patients provided both specimens. The mean pre-operative urinary IL-6/creatinine ratio before the procedure was 1.63 pg/mL. The mean post procedure urinary IL-6/creatinine ratio after the patient was confirmed to be stone-free was 1.81 pg/mL. These were not significantly different (p=0.38). Preoperative urinary IL-6/creatinine ratio did not correlate to stone size (r=0.15) and no correlation was seen between time from treatment and stone free IL-6/creatinine ratio (r=0.48). Urinary IL-6 is not a good screening test for current urolithiasis in stone-forming individuals. It is elevated whether the stone is present or not.

Dehydration of detomidine hydrochloride monohydrate.

PubMed

Veldre, K; Actiņš, A; Jaunbergs, J

2011-10-09

The thermodynamic stability of detomidine hydrochloride monohydrate has been evaluated on the basis of phase transition kinetics in solid state. A method free of empirical models was used for the treatment of kinetic data, and compared to several known solid state kinetic data processing methods. Phase transitions were monitored by powder X-ray diffraction (PXRD) and thermal analysis. Full PXRD profiles were used for determining the phase content instead of single reflex intensity measurements, in order to minimize the influence of particle texture. We compared the applicability of isothermal and nonisothermal methods to our investigation of detomidine hydrochlorine monohydrate dehydration. Copyright © 2011 Elsevier B.V. All rights reserved.

A Search for Interstellar Monohydric Thiols

NASA Astrophysics Data System (ADS)

Gorai, Prasanta; Das, Ankan; Das, Amaresh; Sivaraman, Bhalamurugan; Etim, Emmanuel E.; Chakrabarti, Sandip K.

2017-02-01

It has been pointed out by various astronomers that a very interesting relationship exists between interstellar alcohols and the corresponding thiols (sulfur analog of alcohols) as far as the spectroscopic properties and chemical abundances are concerned. Monohydric alcohols such as methanol and ethanol are widely observed and 1-propanol was recently claimed to have been seen in Orion KL. Among the monohydric thiols, methanethiol (chemical analog of methanol) has been firmly detected in Orion KL and Sgr B2(N2) and ethanethiol (chemical analog of ethanol) has been observed in Sgr B2(N2), though the confirmation of this detection is yet to come. It is very likely that higher order thiols could be observed in these regions. In this paper, we study the formation of monohydric alcohols and their thiol analogs. Based on our quantum chemical calculation and chemical modeling, we find that the Tg conformer of 1-propanethiol is a good candidate of astronomical interest. We present various spectroscopically relevant parameters of this molecule to assist in its future detection in the interstellar medium.

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; Cıkman, 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

Kinetics of calcium oxalate crystal formation in urine.

PubMed

Laube, Norbert; Klein, Florian; Bernsmann, Falk

2017-04-01

It is routinely observed that persons with increased urinary stone risk factors do not necessarily form uroliths. Furthermore, stone formers can present with urinalyses that do not reflect the clinical picture. We explain this discrepancy by differences in crystallization kinetics. In 1162 urines, crystallization of Ca-oxalate was induced according to the BONN-Risk-Index (BRI) method. The urine's relative light transmissivity (RLT) was recorded from 100 % at start of titration to 95 % due to nuclei formation and crystal growth. From the RLT changes, a measure of the thermodynamic inhibition threshold of crystal formation (BRI) and of crystal growth kinetics is derived ("turbidity slope" after crystallization onset). On average, subjects presenting with a low inhibition threshold, i.e., high BRI, also present significantly higher crystal growth rates compared with subjects in lower BRI classes. Only subjects in the highest BRI class show a lower growth rate than expected, probably due to a depletion of supersaturation by massive initial nucleation. With increasing thermodynamic risk of crystal formation (i.e., increasing BRI) due to an imbalance between inhibitors and promoters of crystal formation, an increase in the imbalance between inhibitors and promoters of crystal growth (i.e., increasing growth rate) is observed. Both lead to an increased urolith formation risk. Healthy subjects with increased BRI are an exception to this trend: their urine is thermodynamically prone to form stones, but they show a kinetic inhibition preventing nuclei from significant growth.

Antilithiatic Activity of phlorotannin rich extract of Sarghassum Wightii on Calcium Oxalate Urolithiais – In Vitro and In Vivo Evaluation

PubMed Central

Sujatha, D.; Singh, Kiranpal; Vohra, Mursalin; Kumar, K. Vijay; Sunitha, S.

2015-01-01

ABSTRACT Purpose: Urolithiasis is a common urological disorder responsible for serious human affliction and cost to the society with a high recurrence rate. The aim of the present study was to systematically evaluate the phlorotannin rich extract of Sargassum wightii using suitable in vitro and in vivo models to provide scientific evidence for its antilithiatic activity. Materials and Methods: To explore the effect of Sargassum wightii on calcium oxalate crystallization, in vitro assays like crystal nucleation, aggregation and crystal growth were performed. Calcium oxalate urolithiasis was induced in male Sprague dawley rats using a combination of gentamicin and calculi producing diet (5% ammonium oxalate and rat pellet feed). The biochemical parameters like calcium, oxalate, magnesium, phosphate, sodium and potassium were evaluated in urine, serum and kidney homogenates. Histopathological studies were also done to confirm the biochemical findings. Results: The yield of Sargassum wightii extract was found to be 74.5 gm/kg and confirmed by quantitative analysis. In vitro experiments with Sargassum wightii showed concentration dependent inhibition of calcium oxalate nucleation, aggregation and growth supported by SEM analysis. In the in vivo model, Sargassum wightii reduced both calcium and oxalate supersaturation in urine, serum and deposition in the kidney. The biochemical results were supported by histopathological studies. Conclusion: The findings of the present study suggest that Sargassum wightii has the ability to prevent nucleation, aggregation and growth of calcium oxalate crystals. Sargassum wightii has better preventive effect on calcium oxalate stone formation indicating its strong potential to develop as a therapeutic option to prevent recurrence of urolithiasis. PMID:26200544

Rapid formation of cholesterol crystals in gallbladder bile is associated with stone recurrence after laparoscopic cholecystotomy.

PubMed

Jüngst, D; del Pozo, R; Dolu, M H; Schneeweiss, S G; Frimberger, E

1997-03-01

Laparoscopic cholecystotomy (LCT) with subsequent extraction of gallstones and primary closure of the gallbladder has been introduced as an alternative therapy for patients with cholecystolithiasis and preserved gallbladder function. However, stone recurrence has to be considered as a major drawback that might be related to lithogenic factors of gallbladder bile or the composition of gallbladder stones. Therefore, these were studied in relation to stone recurrence within an observation period of 1 to 5 years (median, 3.6 years) in 50 patients after LCT. The concentrations of total and individual bile acids, phospholipids, cholesterol, total lipids, mucin, protein, and the cholesterol saturation indices in gallbladder bile were not significantly different between 10 patients with and 40 patients without stone recurrence. However, the crystal observation time was significantly (P < .02) shorter (range, 1-2 days; median, 1.5) in the bile of patients with stone recurrence compared to those without (range, 1-21 days, median 3.5). Moreover, all 10 stone recurrences were observed in the 28 patients with a crystal observation time in the bile of less than or equal to 2 days (approximate annual risk: 12%-15%), and no recurrences were observed in the 22 patients with a crystal observation time greater than 2 days (P < .0001) or in patients with pigment stones. The rapid formation of cholesterol monohydrate crystals in bile seems to be the major risk factor for recurrent stones after LCT. These are most likely cholesterol stones and, therefore, are amenable to oral bile-acid prevention or treatment.

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

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

High-Frequency Dusting Versus Conventional Holmium Laser Lithotripsy for Intrarenal and Ureteral Calculi.

PubMed

Li, Roger; Ruckle, David; Keheila, Mohamed; Maldonado, Jonathan; Lightfoot, Michelle; Alsyouf, Muhannad; Yeo, Alexander; Abourbih, Samuel R; Olgin, Gaudencio; Arenas, Javier L; Baldwin, D Duane

2017-03-01

The efficiency of holmium laser lithotripsy for urolithiasis depends upon several factors, including laser pulse energy and frequency and stone composition and retropulsion. This study investigates the complex interplay between these factors and quantifies lithotripsy efficiency using different laser settings in a benchtop kidney and ureter model. In vitro caliceal and ex vivo porcine ureteral models were constructed. Calcium oxalate monohydrate stones were fragmented using a 200-μm laser fiber. In the caliceal model, stone fragmentation and vaporization rates at settings of 0.6 J/5 Hz, 0.2 J/15 Hz, and 0.2 J/50 Hz were compared. In the ureteral model, fragmentation time, retropulsion rate, fragmentation rate, and fragmented stone weight were compared at settings of 0.6 J/5 Hz and 0.2 J/15 Hz. Retropulsive forces generated at 0.6 J/5 Hz, 0.2 J/15 Hz, and 0.2 J/50 Hz settings were compared. Analysis was performed using Student's t-test and one-way ANOVA. In the caliceal model, the 0.6 J/5 Hz setting fragmented and vaporized stones at a higher rate than the 0.2 J/15 Hz setting (0.072 vs. 0.049 mg/s; p < 0.001). However, when the 0.2 J energy setting was combined with the 50 Hz frequency, the fragmentation rate (0.069 mg/s) was similar to the fragmentation rate at 0.6 J/5 Hz (0.072 mg/s; p = 0.677). In the ureteral model, the 0.6 J/5 Hz setting produced higher fragmentation rates (0.089 vs. 0.049 mg/s; p < 0.001), but resulted in significantly lower fragmented stone weight overall (16.815 vs. 25.485 mg; p = 0.009) due to higher retropulsion rates (0.732 vs. 0.213 mm/s; p < 0.001). Retropulsive forces decreased significantly when pulse energy decreased from 0.6 to 0.2 J (0.907 vs. 0.223 N; p < 0.001). Frequency did not affect retropulsive force at 15 and 50 Hz settings (0.223 vs. 0.288 N; p = 0.509). Laser lithotripsy of calcium oxalate monohydrate stones in the ureter

Role of scanning electron microscopy in identifying drugs used in medical practice.

PubMed

Fazil Marickar, Y M; Sylaja, N; Koshy, Peter

2009-10-01

Several plant preparations are administered for treatment of stone disease without scientific basis. This paper presents the results of in vitro and animal experimental studies using scanning electron microscopy (SEM) in the identification of the therapeutic properties of trial drugs in medicine. In the first set of the study, urinary crystals namely calcium oxalate monohydrate and calcium oxalate dehydrate were grown in six sets of Hane's tubes in silica gel medium. Trial drugs namely scoparia dulcis Lynn, musa sapiens and dolicos biflorus were incorporated in the gel medium to identify the dopant effect of the trial drugs on the size and extent of crystal column growth. The changes in morphology of crystals were studied using SEM. In the second set, six male Wistar rats each were calculogenised by administering sodium oxalate and ethylene glycol and diabetised using streptozotocin. The SEM changes of calculogenisation were studied. The rats were administered trial drugs before calculogenisation or after. The kidneys of the rats studied under the scanning electron microscope showed changes in tissue morphology and crystal deposition produced by calculogenisation and alterations produced by addition of trial drugs. The trial drugs produced changes in the pattern of crystal growth and in the crystal morphology of both calcium oxalate monohydrate and calcium oxalate dihydrate grown in vitro. Elemental distribution analysis showed that the crystal purity was not altered by the trial drugs. Scoparia dulcis Lynn was found to be the most effective anticalculogenic agent. Musa sapiens and dolicos biflorus were found to have no significant effect in inhibiting crystal growth. The kidneys of rats on calculogenisation showed different grades of crystals in the glomerulus and interstitial tissues, extrusion of the crystals into the tubular lumen, collodisation and tissue inflammatory cell infiltration. Scoparia dulcis Lynn exhibited maximum protector effect against the

The influence of maternal and paternal history on stone composition and clinical course of calcium nephrolithiasis in subjects aged between 15 and 25.

PubMed

Guerra, Angela; Ticinesi, Andrea; Allegri, Franca; Nouvenne, Antonio; Pinelli, Silvana; Folesani, Giuseppina; Lauretani, Fulvio; Maggio, Marcello; Borghi, Loris; Meschi, Tiziana

2016-11-01

Our aim was to compare the influence of maternal history of stones (MHS) and paternal history of stones (PHS) on composition of calculi and disease course in a group of patients with calcium nephrolithiasis (CN) aged between 15 and 25, the age range with the maximal influence of family history on disease expression. One-hundred thirty-five patients (68 F) with CN and one stone-forming parent were retrospectively selected from the database of our outpatient stone clinic, and categorized according to MHS or PHS. Data about stone disease course and composition of passed calculi, determined by chemical analysis or Fourier-transformed infrared spectrophotometry, were collected together with information on blood chemistry and 24-h urinary profile of lithogenic risk. The characteristics of disease course and stone composition were compared using logistic regression tests adjusted for age, sex, and BMI or analysis of covariance where appropriate. Patients with MHS (n = 46) had significantly higher urinary calcium/creatinine ratio and ammonium, a higher prevalence of urological treatments (57 vs 27 %, p < 0.001) and mixed calcium oxalate/calcium phosphate stone composition (69 vs 35 %, p = 0.002) than those with PHS. At multivariate logistic regression models, MHS was independently associated with urological treatments (OR 4.5, 95 %CI 1.9-10.7, p < 0.001) and the formation of calculi with mixed calcium oxalate/calcium phosphate composition (OR 5.8, 95 %CI 1.9-17.9, p = 0.002). The method of stone analysis did not affect this result. In conclusion, in subjects aged 15-25, MHS is associated with mixed calcium stones and with a higher risk for urological procedures, and should be, therefore, considered in the management of urolithiasis.

Evaluation of low-dose dual energy computed tomography for in vivo assessment of renal/ureteric calculus composition.

PubMed

Mahalingam, Harshavardhan; Lal, Anupam; Mandal, Arup K; Singh, Shrawan Kumar; Bhattacharyya, Shalmoli; Khandelwal, Niranjan

2015-08-01

This study aimed to assess the accuracy of low-dose dual-energy computed tomography (DECT) in predicting the composition of urinary calculi. A total of 52 patients with urinary calculi were scanned with a 128-slice dual-source DECT scanner by use of a low-dose protocol. Dual-energy (DE) ratio, weighted average Hounsfield unit (HU) of calculi, radiation dose, and image noise levels were recorded. Two radiologists independently rated study quality. Stone composition was assessed after extraction by Fourier transform infrared spectroscopy (FTIRS). Analysis of variance was used to determine if the differences in HU values and DE ratios between the various calculus groups were significant. Threshold cutoff values to classify the calculi into separate groups were identified by receiver operating characteristic curve analysis. A total of 137 calculi were detected. FTIRS analysis differentiated the calculi into five groups: uric acid (n=17), struvite (n=3), calcium oxalate monohydrate and dihydrate (COM-COD, n=84), calcium oxalate monohydrate (COM, n=28), and carbonate apatite (n=5). The HU value could differentiate only uric acid calculi from calcified calculi (p<0.001). The DE ratio could confidently differentiate uric acid, struvite, calcium oxalate, and carbonate apatite calculi (p<0.001) with cutoff values of 1.12, 1.34, and 1.66, respectively, giving >80% sensitivity and specificity to differentiate them. The DE ratio could not differentiate COM from COM-COD calculi. No study was rated poor in quality by either of the observers. The mean radiation dose was 1.8 mSv. Low-dose DECT accurately predicts urinary calculus composition in vivo while simultaneously reducing radiation exposure without compromising study quality.

Evaluation of low-dose dual energy computed tomography for in vivo assessment of renal/ureteric calculus composition

PubMed Central

Mahalingam, Harshavardhan; Mandal, Arup K; Singh, Shrawan Kumar; Bhattacharyya, Shalmoli; Khandelwal, Niranjan

2015-01-01

Purpose This study aimed to assess the accuracy of low-dose dual-energy computed tomography (DECT) in predicting the composition of urinary calculi. Materials and Methods A total of 52 patients with urinary calculi were scanned with a 128-slice dual-source DECT scanner by use of a low-dose protocol. Dual-energy (DE) ratio, weighted average Hounsfield unit (HU) of calculi, radiation dose, and image noise levels were recorded. Two radiologists independently rated study quality. Stone composition was assessed after extraction by Fourier transform infrared spectroscopy (FTIRS). Analysis of variance was used to determine if the differences in HU values and DE ratios between the various calculus groups were significant. Threshold cutoff values to classify the calculi into separate groups were identified by receiver operating characteristic curve analysis. Results A total of 137 calculi were detected. FTIRS analysis differentiated the calculi into five groups: uric acid (n=17), struvite (n=3), calcium oxalate monohydrate and dihydrate (COM-COD, n=84), calcium oxalate monohydrate (COM, n=28), and carbonate apatite (n=5). The HU value could differentiate only uric acid calculi from calcified calculi (p<0.001). The DE ratio could confidently differentiate uric acid, struvite, calcium oxalate, and carbonate apatite calculi (p<0.001) with cutoff values of 1.12, 1.34, and 1.66, respectively, giving >80% sensitivity and specificity to differentiate them. The DE ratio could not differentiate COM from COM-COD calculi. No study was rated poor in quality by either of the observers. The mean radiation dose was 1.8 mSv. Conclusions Low-dose DECT accurately predicts urinary calculus composition in vivo while simultaneously reducing radiation exposure without compromising study quality. PMID:26279828

Comparative spectroscopic analysis of urinary calculi inhibition by Larrea Tridentata infusion and NDGA chemical extract

NASA Astrophysics Data System (ADS)

Manciu, Felicia

2012-10-01

In the present comparative spectroscopic study we try to understand calcium oxalate kidney stone formation as well as its inhibition by using a traditional medicine approach with Larrea Tridentata (LT) herbal extracts and nordihydroguaiaretic acid (NDGA), which is a chemical extract of the LT bush. The samples were synthesized without and with LT or NDGA using a simplified single diffusion gel growth technique. While the use of infusion from LT decreases the sizes of calcium oxalate crystals and also changes their structure from monohydrate for pure crystals to dihydrate for crystals grown with different amounts of inhibitor, both Raman and infrared absorption spectroscopic techniques, which are the methods of analysis employed in this work, reveal that NDGA is not responsible for the change in the morphology of calcium oxalate crystals and does not contribute significantly to the inhibition process. The presence of NDGA slightly affects the structure of the crystals by modifying the strength of the C-C bonds as seen in the Raman data. Also, the current infrared absorption results demonstrate the presence of NDGA in the samples through a vibrational line that corresponds to the double bond between carbon atoms of the ester group of NDGA.

Femtosecond laser lithotripsy: feasibility and ablation mechanism.

PubMed

Qiu, Jinze; Teichman, Joel M H; Wang, Tianyi; Neev, Joseph; Glickman, Randolph D; Chan, Kin Foong; Milner, Thomas E

2010-01-01

Light emitted from a femtosecond laser is capable of plasma-induced ablation of various materials. We tested the feasibility of utilizing femtosecond-pulsed laser radiation (lambda=800 nm, 140 fs, 0.9 mJ/pulse) for ablation of urinary calculi. Ablation craters were observed in human calculi of greater than 90% calcium oxalate monohydrate (COM), cystine (CYST), or magnesium ammonium phosphate hexahydrate (MAPH). Largest crater volumes were achieved on CYST stones, among the most difficult stones to fragment using Holmium:YAG (Ho:YAG) lithotripsy. Diameter of debris was characterized using optical microscopy and found to be less than 20 microm, substantially smaller than that produced by long-pulsed Ho:YAG ablation. Stone retropulsion, monitored by a high-speed camera system with a spatial resolution of 15 microm, was negligible for stones with mass as small as 0.06 g. Peak shock wave pressures were less than 2 bars, measured by a polyvinylidene fluoride (PVDF) needle hydrophone. Ablation dynamics were visualized and characterized with pump-probe imaging and fast flash photography and correlated to shock wave pressures. Because femtosecond-pulsed laser ablates urinary calculi of soft and hard compositions, with micron-sized debris, negligible stone retropulsion, and small shock wave pressures, we conclude that the approach is a promising candidate technique for lithotripsy.

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

Evidence for a distinct gut microbiome in kidney stone formers compared to non-stone formers.

PubMed

Stern, Joshua M; Moazami, Saman; Qiu, Yunping; Kurland, Irwin; Chen, Zigui; Agalliu, Ilir; Burk, Robert; Davies, Kelvin P

2016-10-01

with oxalate levels (r = -0.60, p < 0.06) and Escherichia trended to an inverse correlation with citrate (r = -0.56, p < 0.08). We also compared bacterial abundance between uric acid (UA) stone formers (n = 5) and non UA stone formers (n = 18) and found no significant difference between them. We identified two genus of bacteria in the GMB that had significant association with KSD. Interestingly, components of the 24-h urine appear to be correlated to bacterial abundance. These preliminary studies for the first time associate differences in the GMB with kidney stone formation. Further studies are warranted to evaluate the potential causative role of preexisting dysbiosis in kidney stone disease.

Vibrational studies in aqueous solutions. Part II. The acid oxalate ion and oxalic acid

NASA Astrophysics Data System (ADS)

Shippey, T. A.

1980-08-01

Assignments for oxalic acid in solution are re-examined. A detailed assignment of the IR and Raman spectra of the acid oxalate ion is presented for the first time. Raman spectroscopy is used to study the first ionization of oxalic acid.

Oxalate metal complexes in aerosol particles: implications for the hygroscopicity of oxalate-containing particles

NASA Astrophysics Data System (ADS)

Furukawa, T.; Takahashi, Y.

2011-05-01

Atmospheric aerosols have both a direct and an indirect cooling effect that influences the radiative balance at the Earth's surface. It has been estimated that the degree of cooling is large enough to weaken the warming effect of carbon dioxide. Among the cooling factors, secondary organic aerosols (SOA) play an important role in the solar radiation balance in the troposphere as SOA can act as cloud condensation nuclei (CCN) and extend the lifespan of clouds because of their high hygroscopic and water soluble nature. Oxalic acid is an important component of SOA, and is produced via several formation pathways in the atmosphere. However, it is not certain whether oxalic acid exists as free oxalic acid or as metal oxalate complexes in aerosols, although there is a marked difference in their solubility in water and their hygroscopicity. We employed X-ray absorption fine structure spectroscopy to characterize the calcium (Ca) and zinc (Zn) in aerosols collected at Tsukuba in Japan. Size-fractionated aerosol samples were collected for this purpose using an impactor aerosol sampler. It was shown that 10-60% and 20-100% of the total Ca and Zn in the finer particles (<2.1 μm) were present as Ca and Zn oxalate complexes, respectively. Oxalic acid is hygroscopic and can thus increase the CCN activity of aerosol particles, while complexes with various polyvalent metal ions such as Ca and Zn are not hygroscopic, which cannot contribute to the increase of the CCN activity of aerosols. Based on the concentrations of noncomplexed and metal-complexed oxalate species, we found that most of the oxalic acid is present as metal oxalate complexes in the aerosols, suggesting that oxalic acid does not always increase the hygroscopicity of aerosols in the atmosphere. Similar results are expected for other dicarboxylic acids, such as malonic and succinic acids. Thus, it is advisable that the cooling effect of organic aerosols should be estimated by including the information on metal

Synergism between urinary prothrombin fragment 1 and urine: a comparison of inhibitory activities in stone-prone and stone-free population groups.

PubMed

Webber, Dawn; Rodgers, Allen L; Sturrock, Edward D

2002-09-01

South African blacks rarely form kidney stones compared with whites. This study investigated whether purified urinary prothrombin fragment 1 (UPTF1) derived from blacks is a more potent inhibitor of calcium oxalate crystallisation than that from whites. UPTF1 was purified from the urine of both population groups and their inhibitory activities were compared in a cross-over design in which each protein was tested in ultrafiltered urine from both population groups. Coulter Multisizer, [14C]-oxalate deposition and scanning electron microscopy experiments were used to monitor crystallisation. The study has demonstrated for the first time that UPTF1 promotes nucleation and that inhibitory activity is synergistically dependent upon urine composition. The activity of the whites' UPTF1 was greater than that of the blacks in the whites' urine (e.g. particle size decrease: 31.7% vs. 25.2%), while the blacks' UPTF1 was superior to that of the whites in the blacks' urine (e.g. particle size decrease: 46.5% vs. 32.4%). In addition, when tested in their respective endogenous urines, the blacks' UPTF1 demonstrated superior inhibitory activity on an absolute scale (e.g. particle size decrease: 46.5% vs. 31.7%). Thus, the urine composition of black South Africans may influence their UPTF1 conformation, conferring greater efficacy for inhibition of calcium oxalate crystallisation.

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

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

The Role of the Papillary Epithelium in Stone Growth

NASA Astrophysics Data System (ADS)

Bergsland, Kristin J.

2007-04-01

The papillary surface epithelium (PSE) covers the renal papilla in mammalian kidneys and serves as a diffusion barrier between the urine on the apical surface and the interstitium on the basolateral surface. The PSE also plays a physiological role in transport of solutes between the urine and interstitium both by active transport and paracellular pathways. Permeability of the PSE may be affected by alterations in specific transporters, components of intercellular tight junctions, cell surface glycosaminoglycans and urine composition. In idiopathic calcium oxalate (CaOx) stone formers, apatite deposits known as Randall's plaque form in the papillary interstitium and lodge beneath the PSE. The presence of plaque may perturb the normal function of the PSE, possibly by provoking the up-regulation of pro-inflammatory cytokines such as TNFα in the interstitium. Disruption of the epithelial barrier may lead to increased permeability and exposure of the plaque matrix to urine constituents, followed by loss of the PSE and growth of CaOx stone over the plaque. To investigate the role of the PSE in stone development, new experimental systems are needed, including animal models of plaque formation as well as cell culture systems for papillary epithelial cells.

Metabolic Conversion of l-Ascorbic Acid to Oxalic Acid in Oxalate-accumulating Plants 1

PubMed Central

Yang, Joan C.; Loewus, Frank A.

1975-01-01

l-Ascorbic acid-1-14C and its oxidation product, dehydro-l-ascorbic acid, produced labeled oxalic acid in oxalate-accumulating plants such as spinach seedlings (Spinacia oleracea) and the detached leaves of woodsorrel (Oxalis stricta and O. oregana), shamrock (Oxalis adenopylla), and begonia (Begonia evansiana). In O. oregana, conversion occurred equally well in the presence or absence of light. This relationship between l-ascorbic acid metabolism and oxalic acid formation must be given careful consideration in attempts to explain oxalic accumulation in plants. PMID:16659288

Risk of calcium oxalate nephrolithiasis in postmenopausal women supplemented with calcium or combined calcium and estrogen.

PubMed

Domrongkitchaiporn, Somnuek; Ongphiphadhanakul, Boonsong; Stitchantrakul, Wasana; Chansirikarn, Sirinthorn; Puavilai, Gobchai; Rajatanavin, Rajata

2002-02-26

Recent studies showed that postmenopausal women lost less bone mass when supplemented with calcium or estrogen therapy. However, the safety of the treatments in terms of the risk of calcium oxalate stone formation is unknown. We therefore conducted this study to determine the alteration in calcium oxalate supersaturation after calcium supplement or after combined calcium and estrogen therapy in postmenopausal osteoporotic women. Fifty-six postmenopausal women were enrolled in this study. All subjects were more than 10 years postmenopausal with vertebral or femoral osteoporosis by bone mineral density criteria. They were randomly allocated to receive either 625 mg of calcium carbonate (250 mg of elemental calcium) at the end of a meal three times a day (group A, n=26) or calcium carbonate in the same manner plus 0.625 mg/day of conjugated equine estrogen and 5 mg medrogestone acetate from day 1-12 each month (group B, n=30). The age (mean +/- S.E.M.) was 66.3 +/- 1.2 and 65.1 +/- 1.1 years, weight 54.1 +/- 1.2 and 55.3 +/- 2.1 kg, in group A and group B, respectively. Urine specimens (24-h) were collected at baseline and 3 months after treatment for the determination of calcium oxalate saturation by using Tiselius's index (AP(CaOx)) and calcium/citrate ratio. After 3 months of treatment, there was no significant alteration from baseline for urinary excretion of calcium, citrate and oxalate. Urinary phosphate excretion was significantly reduced (6.3 +/- 0.7 vs. 5.1 +/- 0.7 mmol/day for group A and 8.2 +/- 0.9 vs. 5.8 +/- 0.7 mmol/day for group B, P<0.05), whereas net alkaline absorption was significantly elevated (10.1 +/- 3.6 vs. 20.1 +/- 4.4 meq/day for group A and 4.8 +/- 3.2 vs. 19.9 +/- 3.6 meq/day for group B, P<0.05). Calcium/citrate ratio and AP(CaOx) determined at baseline were not different from the corresponding values after treatment in both groups; calcium/citrate: 10.1 +/- 3.1 vs. 10.1 +/- 2.5 for group A and 9.3 +/- 1.8 vs. 11.9 +/- 2.5 for group B and

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.

Calcium oxalate crystals induces tight junction disruption in distal renal tubular epithelial cells by activating ROS/Akt/p38 MAPK signaling pathway.

PubMed

Yu, Lei; Gan, Xiuguo; Liu, Xukun; An, Ruihua

2017-11-01

Tight junction plays important roles in regulating paracellular transports and maintaining cell polarity. Calcium oxalate monohydrate (COM) crystals, the major crystalline composition of kidney stones, have been demonstrated to be able to cause tight junction disruption to accelerate renal cell injury. However, the cellular signaling involved in COM crystal-induced tight junction disruption remains largely to be investigated. In the present study, we proved that COM crystals induced tight junction disruption by activating ROS/Akt/p38 MAPK pathway. Treating Madin-Darby canine kidney (MDCK) cells with COM crystals induced a substantial increasing of ROS generation and activation of Akt that triggered subsequential activation of ASK1 and p38 mitogen-activated protein kinase (MAPK). Western blot revealed a significantly decreased expression of ZO-1 and occludin, two important structural proteins of tight junction. Besides, redistribution and dissociation of ZO-1 were observed by COM crystals treatment. Inhibition of ROS by N-acetyl-l-cysteine (NAC) attenuated the activation of Akt, ASK1, p38 MAPK, and down-regulation of ZO-1 and occludin. The redistribution and dissociation of ZO-1 were also alleviated by NAC treatment. These results indicated that ROS were involved in the regulation of tight junction disruption induced by COM crystals. In addition, the down-regulation of ZO-1 and occludin, the phosphorylation of ASK1 and p38 MAPK were also attenuated by MK-2206, an inhibitor of Akt kinase, implying Akt was involved in the disruption of tight junction upstream of p38 MAPK. Thus, these results suggested that ROS-Akt-p38 MAPK signaling pathway was activated in COM crystal-induced disruption of tight junction in MDCK cells.

Extensive characterizations of bacteria isolated from catheterized urine and stone matrices in patients with nephrolithiasis.

PubMed

Tavichakorntrakool, Ratree; Prasongwattana, Vitoon; Sungkeeree, Seksit; Saisud, Phitsamai; Sribenjalux, Pipat; Pimratana, Chaowat; Bovornpadungkitti, Sombat; Sriboonlue, Pote; Thongboonkerd, Visith

2012-11-01

Urinary tract infections are generally known to be associated with nephrolithiasis, particularly struvite stone, in which the most common microbe found is urea-splitting bacterium, i.e. Proteus mirabilis. However, our observation indicated that it might not be the case of stone formers in Thailand. We therefore extensively characterized microorganisms associated with all types of kidney stones. A total of 100 kidney stone formers (59 males and 41 females) admitted for elective percutaneous nephrolithotomy were recruited and microorganisms isolated from catheterized urine and cortex and nidus of their stones were analyzed. From 100 stone formers recruited, 36 cases had a total of 45 bacterial isolates cultivated from their catheterized urine and/or stone matrices. Among these 36 cases, chemical analysis by Fourier-transformed infrared spectroscopy revealed that 8 had the previously classified 'infection-induced stones', whereas the other 28 cases had the previously classified 'metabolic stones'. Calcium oxalate (in either pure or mixed form) was the most common and found in 64 and 75% of the stone formers with and without bacterial isolates, respectively. Escherichia coli was the most common bacterium (approximately one-third of all bacterial isolates) found in urine and stone matrices (both nidus and periphery). Linear regression analysis showed significant correlation (r = 0.860, P < 0.001) between bacterial types in urine and stone matrices. Multidrug resistance was frequently found in these isolated bacteria. Moreover, urea test revealed that only 31% were urea-splitting bacteria, whereas the majority (69%) had negative urea test. Our data indicate that microorganisms are associated with almost all chemical types of kidney stones and urea-splitting bacteria are not the major causative microorganisms found in urine and stone matrices of the stone formers in Thailand. These data may lead to rethinking and a new roadmap for future research regarding the role of

Oxalate analysis methodology for decayed wood

Treesearch

Carol A. Clausen; William Kenealy; Patricia K. Lebow

2008-01-01

Oxalate from partially decayed southern pine wood was analyzed by HPLC or colorimetric assay. Oxalate extraction efficiency, assessed by comparing analysis of whole wood cubes with ground wood, showed that both wood geometries could be extracted with comparable efficiency. To differentiate soluble oxalate from total oxalate, three extraction methods were assessed,...

Biochemical and dietary factors of uric acid stone formation.

PubMed

Trinchieri, Alberto; Montanari, Emanuele

2018-04-01

The aim of this study was to compare the clinical characteristics of "pure" uric acid renal stone formers (UA-RSFs) with that of mixed uric acid/calcium oxalate stone formers (UC-RSFs) and to identify which urinary and dietary risk factors predispose to their formation. A total of 136 UA-RSFs and 115 UC-RSFs were extracted from our database of renal stone formers. A control group of 60 subjects without history of renal stones was considered for comparison. Data from serum chemistries, 24-h urine collections and 24-h dietary recalls were considered. UA-RSFs had a significantly (p = 0.001) higher body mass index (26.3 ± 3.6 kg/m 2 ) than UC-RSFs, whereas body mass index of UA-RSFs was higher but not significantly than in controls (24.6 ± 4.7) (p = 0.108). The mean urinary pH was significantly lower in UA-RSFs (5.57 ± 0.58) and UC-RSFs (5.71 ± 0.56) compared with controls (5.83 ± 0.29) (p = 0.007). No difference of daily urinary uric acid excretion was observed in the three groups (p = 0.902). Daily urinary calcium excretion was significantly (p = 0.018) higher in UC-RSFs (224 ± 149 mg/day) than UA-RSFs (179 ± 115) whereas no significant difference was observed with controls (181 ± 89). UA-RSFs tend to have a lower uric acid fractional excretion (0.083 ± 0.045% vs 0.107+/-0.165; p = 0.120) and had significantly higher serum uric acid (5.33 ± 1.66 vs 4.78 ± 1.44 mg/dl; p = 0.007) than UC-RSFs. The mean energy, carbohydrate and vitamin C intakes were higher in UA-SFs (1987 ± 683 kcal, 272 ± 91 g, 112 ± 72 mg) and UC-SFs (1836 ± 74 kcal, 265 ± 117, 140 ± 118) with respect to controls (1474 ± 601, 188 ± 84, 76 ± 53) (p = 0.000). UA-RSFs should be differentiated from UC-RSFs as they present lower urinary pH, lower uric acid fractional excretion and higher serum uric acid. On the contrary, patients with UC-RSFs show urinary risk factors

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.

Oxalate, inflammasome, and progression of kidney disease

PubMed Central

Ermer, Theresa; Eckardt, Kai-Uwe; Aronson, Peter S.; Knauf, Felix

2016-01-01

Purpose of review Oxalate is an end product of metabolism excreted via the kidney. Excess urinary oxalate, whether from primary or enteric hyperoxaluria, can lead to oxalate deposition in the kidney. Oxalate crystals are associated with renal inflammation, fibrosis and progressive renal failure. It has long been known that as glomerular filtration rate (GFR) becomes reduced in chronic kidney disease (CKD), there is striking elevation of plasma oxalate. Taken together, these findings raise the possibility that elevation of plasma oxalate in CKD may promote renal inflammation and more rapid progression of CKD independent of primary etiology. Recent findings The inflammasome has recently been identified to play a critical role in oxalate-induced renal inflammation. Oxalate crystals have been shown to activate the nucleotide-binding domain, leucine-rich repeat inflammasome 3 (also known as NALP3, NLRP3 or cryopyrin), resulting in release of Interleukin-1β and macrophage infiltration. Deletion of inflammasome proteins in mice protects from oxalate-induced renal inflammation and progressive renal failure. Summary The findings reviewed in this article expand our understanding of the relevance of elevated plasma oxalate levels leading to inflammasome activation. We propose that inhibiting oxalate-induced inflammasome activation, or lowering plasma oxalate, may prevent or mitigate progressive renal damage in CKD, and warrants clinical trials. PMID:27191349

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 sirup...

The effect of hydrodynamic and thermodynamic factors and the addition of citric acid on the precipitation of calcium oxalate dihydrate.

PubMed

Šter, Anamarija; Šafranko, Silvija; Bilić, Katarina; Marković, Berislav; Kralj, Damir

2018-06-01

This paper reports on the investigation of experimental conditions relevant for spontaneous precipitation of significant amount of pure calcium oxalate dihydrate (COD). For this purpose, the hydrodynamic and thermodynamic parameters, such as mode of agitation, temperature, supersaturation and concentration of additives (citrate ions), have been studied. The results show that in the model systems, without the citrate addition and applied mechanical stirring, calcium oxalate monohydrate (COM) was observed as dominant modification after 20 min of aging, while the magnetic stirring resulted in a formation of a mixture of COM and calcium oxalate trihydrate (COT), regardless of the temperature applied. In the mechanically stirred systems, the addition of citrate ions in the range of concentrations, 0.001 mol dm -3  < c i (Na 3 C 6 H 5 O 7 ) < 0.012 mol dm -3 , caused the formation of COM and COD mixture at all temperatures. At the same conditions and in the magnetically stirred systems formation of COD, in a mixture with COT or COM, has been observed. The highest COD content in the mechanically stirred system was obtained at 45 °C and c i (Na 3 C 6 H 5 O 7 ) = 0.001 mol dm -3 (w = 89.5%), while in the magnetically stirred system almost pure COD was obtained at 37 °C and c i (Na 3 C 6 H 5 O 7 ) = 0.008 mol dm -3 (w = 96.5%).

The bioavailability of oxalate from Oca (Oxalis tuberosa).

PubMed

Albihn, P B; Savage, G P

2001-08-01

It is believed that soluble oxalate has higher bioavailability than insoluble oxalate. Oca (Oxalis tuberosa) is moderately high in oxalate and contains oxalate in soluble form only. We estimated the bioavailability of oxalate in oca based on the urinary excretion of oxalate after oxalate loading with oca to estimate the bioavailability of oxalate in oca. We also clarified whether bioavailability differs in various oxalate loads from the same food source and studied the effect of an additional calcium source on the bioavailability of oxalate from oca. Four men and 4 women ingested 50, 100 and 150 gm. oca as well as 100 gm. oca with 100 gm. sour cream. Oxalate was measured in a 6-hour urine sample from each volunteer. The mean bioavailability of oxalate from oca plus or minus standard deviation was 1.44% +/- 1.31% during the 6-hour period after intake. There was no significant difference in oxalate bioavailability among oxalate intake levels in this study, although oca consumption with sour cream significantly decreased the uptake of oxalate (p <0.01). The variation in bioavailability among individuals was high in our study. The bioavailability of oxalate in oca appears to be similar to that in spinach. However, bioavailability varies among individuals and depends on other constituents of a combined meal.

BIOPSY PROVEN MEDULLARY SPONGE KIDNEY: Clinical findings, histopathology, and role of osteogenesis in stone and plaque formation

PubMed Central

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

2015-01-01

Medullary sponge kidney (MSK) is associated with recurrent stone formation, but the clinical phenotype is unclear because patients with other disorders may be incorrectly labeled MSK. We studied 12 patients with histologic findings pathognomonic of MSK. All patients had an endoscopically recognizable pattern of papillary malformation, which may be segmental or diffuse. Affected papillae are enlarged and billowy, due to markedly enlarged inner medullary collecting ducts (IMCD), which contain small, mobile ductal stones. Patients had frequent dilation of Bellini ducts, with occasional mineral plugs. Stones may form over white (Randall’s) plaque, but most renal pelvic stones are not attached, and have a similar morphology as ductal stones, which are a mixture of calcium oxalate and apatite. Patients had no abnormalities of urinary acidification or acid excretion; the most frequent metabolic abnormality was idiopathic hypercalciuria. Although both Runx2 and Osterix are expressed in papillae of MSK patients, no mineral deposition was seen at the sites of gene expression, arguing against a role of these genes in this process. Similar studies in idiopathic calcium stone formers showed no expression of these genes at sites of Randall’s plaque. The most likely mechanism for stone formation in MSK appears to be crystallization due to urinary stasis in dilated IMCD with subsequent passage of ductal stones into the renal pelvis where they may serve as nuclei for stone formation. PMID:25615853

Ascorbic Acid Intake and Oxalate Synthesis

PubMed Central

Knight, John; Madduma-Liyanage, Kumudu; Mobley, James A.; Assimos, Dean G.; Holmes, Ross P.

2016-01-01

In humans approximately 60 mg of ascorbic acid (AA) breaks down in the body each day and has to be replaced by a dietary intake of 70 mg in females and 90 mg in males to maintain optimal health and AA homeostasis. The breakdown of AA is non-enzymatic and results in oxalate formation. The exact amount of oxalate formed has been difficult to ascertain primarily due to the limited availability of healthy human tissue for such research and the difficulty in measuring AA and its breakdown products. The breakdown of 60 mg of AA to oxalate could potentially result in the formation of up to 30 mg oxalate per day. This exceeds our estimates of the endogenous production of 10 – 25 mg oxalate per day, indicating that degradative pathways that do not form oxalate exist. In this review we examine what is known about the pathways of AA metabolism and how oxalate forms. We further identify how gaps in our knowledge may be filled to more precisely determine the contribution of AA breakdown to oxalate production in humans. The use of stable isotopes of AA to directly assess the conversion of vitamin to oxalate should help fill this void. PMID:27002809

Molecular interactions in the betaine monohydrate-polyol deep eutectic solvents: Experimental and computational studies

NASA Astrophysics Data System (ADS)

Zahrina, Ida; Mulia, Kamarza; Yanuar, Arry; Nasikin, Mohammad

2018-04-01

DES (deep eutectic solvents) are a new class of ionic liquids that have excellent properties. The strength of interaction between molecules in the DES affects their properties and applications. In this work, the strength of molecular interactions between components in the betaine monohydrate salt and polyol (glycerol or/and propylene glycol) eutectic mixtures was studied by experimental and computational studies. The melting point and fusion enthalpy of the mixtures were measured using STA (Simultaneous Thermal Analyzer). The nature and strength of intermolecular interactions were observed by FT-IR and NMR spectroscopy. The molecular dynamics simulation was used to determine the number of H-bonds, percent occupancy, and radial distribution functions in the eutectic mixtures. The interaction between betaine monohydrate and polyol is following order: betaine monohydrate-glycerol-propylene glycol > betaine monohydrate-glycerol > betaine monohydrate-propylene glycol, where the latter is the eutectic mixture with the lowest stability, strength and extent of the hydrogen bonding interactions between component molecules. The presence of intra-molecular hydrogen bonding interactions, the inter-molecular hydrogen bonding interactions between betaine molecule and polyol, and also interactions between polyol and H2O of betaine monohydrate in the eutectic mixtures.

Investigation into structure and dehydration dynamic of gallic acid monohydrate: A Raman spectroscopic study.

PubMed

Cai, Qiang; Xue, Jiadan; Wang, Qiqi; Du, Yong

2018-05-02

The dehydration process of gallic acid monohydrate was carried out by heating method and characterized using Raman spectroscopic technique. Density functional theory calculation with B3LYP function is applied to simulate optimized structures and vibrational frequencies of anhydrous gallic acid and its corresponding monohydrated form. Different vibrational modes are assigned by comparison between experimental and theoretical Raman spectra of above two polymorphs. Raman spectra show that vibrational modes of the monohydrate are distinctively different from those of anhydrous one. Meanwhile, the dynamic information about dehydration process of gallic acid monohydrate could also be observed and monitored directly with the help of Raman spectral analysis. The decay rate of the characteristic band from gallic acid monohydrate and the growth rate of anhydrous one are pretty consistent with each other. It indicates that there is no intermediate present during the dehydration process of gallic acid monohydrate. The results could offer us benchmark works for identifying both anhydrous and hydrated pharmaceutical compounds, characterizing their corresponding molecular conformation within various crystalline forms, and also providing useful information about the process of dehydration dynamic at the microscopic molecular level. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Total flavonoids of Desmodium styracifolium attenuates the formation of hydroxy-L-proline-induced calcium oxalate urolithiasis in rats.

PubMed

Zhou, Jianfu; Jin, Jing; Li, Xiong; Zhao, Zhongxiang; Zhang, Lei; Wang, Qian; Li, Jing; Zhang, Qiuhong; Xiang, Songtao

2018-06-01

Desmosium styracifolium (D. styracifolium), which is considered as a Chinese herbal medicine, has been reported to treat the kidney stone diseases. However, the potential phytochemically active components and the underlying mechanisms associated with its efficacy in targeting urolithiasis remain to be elucidated. This study aims to investigate the anti-urolithiatic effect of total flavonoids of D. styracifolium (TFDS) on calcium oxalate (CaOx) renal stones in Sprague-Dawley rats. Animal models of CaOx urolithiasis were established in male Sprague-Dawley rats by adding 5% w/w hydroxy-L-proline (HLP) in regular rat chow. The TFDS orally at 100, 400 mg/kg, respectively, were administered along with HLP for 28 days. At the end of 28 days of treatment, urine and serum samples were collected for crystalluria determination and various biochemical analysis. Kidney tissues were isolated and processed for antioxidant parameters measurement and histopathological examinations. HLP-induced hyperoxaluria alone reliably caused CaOx nephrolithiasis in rats. We showed that TFDS significantly reduced crystalluria and CaOx crystal deposits in the kidney sections as compared to untreated HLP group. Also, TFDS was observed to decrease urinary oxalate excretion, alleviate the pro-acidosis condition, improve the impaired renal functions and renal epithelial cell injury. Moreover, TFDS protected against the oxidative stress changes via reducing MDA content, increasing CAT and GSH-Px activities in renal homogenate, as well as attenuating the expression of MCP-1, OPN and TGF-β proteins. These results indicated that TFDS had beneficial effect on inhibition of CaOx formation in the rat kidney probably through a combination of antioxidant, anti-inflammatory, urine alkalinizing activities, and lowering the concentration of urinary stone-forming constituents. Thus, TFDS might have clinical implications in preventing oxidative renal cell injury and, ultimately, kidney stone formation. The

Oxalate deposition on asbestos bodies.

PubMed

Ghio, Andrew J; Roggli, Victor L; Richards, Judy H; Crissman, Kay M; Stonehuerner, Jacqueline D; Piantadosi, Claude A

2003-08-01

We report on a deposition of oxalate crystals on ferruginous bodies after occupational exposure to asbestos demonstrated in 3 patients. We investigated the mechanism and possible significance of this deposition by testing the hypothesis that oxalate generated through nonenzymatic oxidation of ascorbate by asbestos-associated iron accounts for the deposition of the crystal on a ferruginous body. Crocidolite asbestos (1000 microg/mL) was incubated with 500 micromol H(2)O(2) and 500 micromol ascorbate for 24 hours at 22 degrees C. The dependence of oxalate generation on iron-catalyzed oxidant production was tested with the both the metal chelator deferoxamine and the radical scavenger dimethylthiourea. Incubation of crocidolite, H(2)O(2), and ascorbate in vitro generated approximately 42 nmol of oxalate in 24 hours. Oxalate generation was diminished significantly by the inclusion of either deferoxamine or dimethylthiourea in the reaction mixture. Incubation of asbestos bodies and uncoated fibers isolated from human lung with 500 micromol H(2)O(2) and 500 micromol ascorbate for 24 hours at 22 degrees C resulted in the generation of numerous oxalate crystals. We conclude that iron-catalyzed production of oxalate from ascorbate can account for the deposition of this crystal on ferruginous bodies.

Potential Pharmacologic Treatments for Cystinuria and for Calcium Stones Associated with Hyperuricosuria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldfarb, David S.

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 advantagesmore » 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.« less

[Epidemiological study on urinary stones in the region of Fez and the risk of recurrence].

PubMed

El Habbani, R; Chaqroune, A; Sqalli Houssaini, T; Arrayhani, M; El Ammari, J; Dami, F; Chouhani, B A; Lahrichi, A

2016-04-01

In Morocco, few works on morpho-constitutional analysis of urinary calculi have been published, especially for patients in the region of Fez. This work aims to make a retrospective epidemiological study on the nature of urinary calculi with patients from the region of Fez and control the urine of the same patients after a period of three months to report on the risk of recurrence. Urinary stones were collected mostly in the nephrology service and urology service at the Hassan II Hospital in Fez. These calculations after being dried for 24 hours at room temperature underwent a morphological analysis, followed by infrared spectroscopic analysis Fourier transform. After a period of about three months, morning urine of the same patients was analyzed by crystalluria to control the presence of crystals that reflect a risk of recurrence. In our series of 123 samples, the age of patients ranges from 2-79 years. The prevalence was higher for men with a sex ratio of 1.3. The results of the analysis calculations showed that 61% were formed of calcium oxalate and 15% of uric acid and 25% of stones were carbapatite, struvite, cystine… The study by crystalluria urine revealed the presence of the crystals in 69% of patients' nephrolithiasis. The results of our study are conformed to the series of results in other regions of Morocco regarding the predominance of calcium oxalate stones. The presence of crystals in the urine of 69% of patients may indicate other recurrences. 4. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Correlation between chemical components of billary calculi and bile & sera and bile of gallstone patients.

PubMed

Chandran, Prasheeda; Garg, Pradeep; Pundir, Chandra S

2005-07-01

Total cholesterol, total bilirubin, calcium, oxalate, inorganic phosphate, magnesium, iron, copper, sodium and potassium were analyzed quantitatively in gallstones, bile of gall bladder and sera of 200 patients of cholelithiasis (52 cholesterol, 76 mixed and 72 pigment stone patients) and their contents were correlated between calculi and bile and sera and bile in these three type of stone patients. A significant positive correlation was observed between total cholesterol, total bilirubin of calculi and bile, copper of bile and sera of cholesterol stone patients, copper of calculi and bile, total bilirubin, oxalate, magnesium, potassium of sera and bile of pigment stone patients and oxalate and iron of stone and bile, total bilirubin, oxalate, sodium of sera and bile of mixed stone patients. A significant negative correlation was found between magnesium of serum and bile of cholesterol stone patients, oxalate of calculi and bile of pigment stone patients and magnesium of serum and bile of mixed stone patients.

Human kidney stone matrix: Latent potential to restrain COM induced cytotoxicity and inflammatory response.

PubMed

Narula, Shifa; Tandon, Simran; Baligar, Prakash; Singh, Shrawan Kumar; Tandon, Chanderdeep

2017-12-25

Kidney stone disease is a multi-factorial disorder resulting from the interplay of various risk factors including lifestyle, environment and genetics along with metabolic activities inside the body. However, it is difficult to determine how these factors converge to promote stone disease. Extensive investigations of kidney stone composition at the molecular level have been carried out however; its impact on the complex mechanism of stone formation is still obscure. Hence, an in vitro study was designed to investigate the attenuation of calcium oxalate toxicity by human kidney stone matrix proteins on NRK-52E cells using flowcytometry, Western blotting, RT-PCR and immunofluorescence assays. Morphological alterations in cell-crystal interaction were assessed using scanning electron microscopy. Microscopic studies showed profound impairment of COM crystal structure as a consequence of protein-crystal interactions. RT-PCR analysis and immunocytochemistry of NRK-52E cells revealed the up-regulation of inflammatory and stress biomarkers OPN and HSP-70, respectively, in response to COM toxicity; which diminished significantly in the presence of kidney stone matrix proteins. The results of present study propose that the mechanism undertaken by matrix proteins to attenuate COM induced cytotoxicity could be attributed to the modulation of crystal structure, which subsequently restraint the inflammatory response and apoptotic cell death. The inference drawn through this study could provide better understanding of the intricate process of kidney stone formation. Copyright © 2017 Elsevier B.V. All rights reserved.

Osteopontin regulates adhesion of calcium oxalate crystals to renal epithelial cells.

PubMed

Yasui, Takahiro; Fujita, Keiji; Asai, Kiyofumi; Kohri, Kenjiro

2002-02-01

The association of calcium crystals with renal tubular cells is an important factor during the formation of urinary stones. We previously reported the strong expression of osteopontin (OPN) on renal tubular cells in the stone-forming kidney, suggesting that OPN plays a role in the crystal-cell interaction. In the present study, we examined the biological consequences of inhibiting OPN expression at the translational level on the formation and adhesion of crystals. We synthesized antisense OPN expression vector (pTet-OPNas) using the tetracycline-regulated expression system. The pTet-OPNas was constructed using a mouse OPN cDNA sequence in an inverted (antisense) orientation. Two clones (NRK-52E/ASs) were identified by transfection of pTet-OPNas into NRK-52E cells and they showed a marked reduction of OPN synthesis in the absence of tetracycline. Calcium oxalate (CaOx) crystal suspension was spread homogeneously on top of the NRK-52E cells. After incubation, the association of CaOx crystals and cells was visualized by scanning electron microscopy. Intact NRK-52E cells, NRK-52E cells transfected with empty vector and tetracycline-treated antisense clones (NRK-52E/ASs), under identical conditions, were associated with CaOx crystals. In contrast, the expression of antisense OPN prevented the association of CaOx crystals with NRK-52E cells. Osteopontin plays a crucial role in the adhesion process of CaOx crystals to renal tubular cells in stone formation.

Patho-physiological evaluation of Duranta erecta for the treatment of urolithiasis.

PubMed

Agawane, Sachin B; Gupta, Vidya S; Kulkarni, Mahesh J; Bhattacharya, Asish K; Koratkar, Santosh S; Rao, Vamkudoth Koteswara

2018-04-07

Urolithiasis is the third common disorder of the urinary system affecting 10-15% of the general population. In recent years, search for new antilithiatic drugs from natural sources has assumed greater importance. This study was performed to investigate the anti-urolithiatic activity of methanolic extract of Duranta erecta leaves by in vitro and in vivo analysis. The study was designed to determine presence of phytochemicals in D. erecta, its yield in percentage, antioxidant activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and anti-microbial property against few bacteria. In vitro analysis was carried out study anti-urolithiatic property of D. erecta by nucleation assay and synthetic urine assay for inhibition of calcium oxalate and calcium oxalate monohydrate crystals formation. An in vivo experiment was performed on Wistar rats for confirmation of anti-urolithiatic property of D. erecta in animal model. D. erecta has the presence of primary and secondary metabolites like glycoside, saponins, sterols, flavonoids, phenols, tannins, alkaloids, carbohydrates and proteins. Methanolic extract of D. erecta gave a very good yield (60%). D. erecta proved its antioxidant potential by 93.51% inhibition of DPPH radical at a concentration of 1000 μg/mL where ascorbic showed 94.71% of DPPH radical at the same concentration. In vitro tests like nucleation assay and synthetic urine assay showed that D. erecta inhibits formation of calcium oxalate and calcium oxalate monohydrate crystals. It also showed the anti-microbial property by formation of zone of inhibition against few bacteria. An in vivo experiment on Wistar rat animal model confirmed the anti-urolithiatic property of D. erecta L. leaves extract. Based on the results, we reported that D. erecta may treat calcium oxalate crystal deposition in the kidney by preventing hyperoxaluria-induced peroxidative damage to the renal tubular membrane surface (lipid peroxidation). It has anti-microbial potential so it may also

BIOCHEMICAL EFFECTS IN NORMAL AND STONE FORMING RATS TREATED WITH THE RIPE KERNEL JUICE OF PLANTAIN (MUSA PARADISIACA)

PubMed Central

Devi, V. Kalpana; Baskar, R.; Varalakshmi, P.

1993-01-01

The effect of Musa paradisiaca stem kernel juice was investigated in experimental urolithiatic rats. Stone forming rats exhibited a significant elevation in the activities of two oxalate synthesizing enzymes - Glycollic acid oxidase and Lactate dehydrogenase. Deposition and excretion of stone forming constituents in kidney and urine were also increased in these rats. The enzyme activities and the level of crystalline components were lowered with the extract treatment. The extract also reduced the activities of urinary alkaline phosphatase, lactate dehydrogenase, r-glutamyl transferase, inorganic pyrophosphatase and β-glucuronidase in calculogenic rats. No appreciable changes were noticed with leucine amino peptidase activity in treated rats. PMID:22556626

Effects of vitamin E ingestion on plasma and urinary risk factors for calcium oxalate urolithiasis in two population groups having different stone-risk profiles: evidence of different physiological handling mechanisms.

PubMed

Theka, Takalani; Rodgers, Allen; Lewandowski, Sonja; Webber, Dawn; Allie-Hamdulay, Shameez

2012-04-01

It has been demonstrated that vitamin E supplementation reduces calciuria and oxaluria and that it may also prevent oxalate-mediated peroxidative injury, all of which reduce the risk of calcium oxalate urolithiasis. In view of the significant difference in stone occurrence in black (B) and white (W) South Africans, we undertook to investigate the effects of vitamin E supplementation in subjects from these two groups. Five healthy males from each group ingested one capsule (400 IU) of vitamin E daily for 60 days. Blood and 24 h urine samples were collected at baseline and on day 60; 24 h dietary questionnaires were simultaneously completed. Urine composition was determined by routine analyses. Urinary and plasma TBARS were determined using a commercially available assay kit while plasma vitamin E was determined by reverse phase HPLC. Plasma vitamin E increased significantly in W but not in B. Urinary and plasma TBARS did not increase in either group. Urinary citrate increased significantly in both groups but the percentage increase in W (169%) was greater than that in B (82%). No other urinary parameter changed significantly. The increase in plasma vitamin E in W but not in B suggests either that the mechanism by which it is packaged into chylomicrons, which are secreted into the systemic circulation, is suppressed in the latter group or that it is differentially absorbed in the two groups. Similarly, to explain the greater increase in citraturia in W compared to B, we speculate that inhibition of lipogenesis of arachidonic acid by vitamin E, ultimately leading to an increase in citraturia, occurs to a lesser extent in B than in W.

Nephrolithiasis, stone composition, meteorology, and seasons in Malta: Is there any connection?

PubMed

Buttigieg, Jesmar; Attard, Stephanie; Carachi, Alexander; Galea, Ruth; Fava, Stephen

2016-01-01

The effect of seasons and meteorology on the incidence of nephrolithiasis has been studied in various regions around the globe, but seldom in the Mediterranean. This retrospective analysis aims at investigating these putative effects in the Maltese Islands, whose climate is typically Mediterranean, followed by a systematic review of the literature. Submission rate and chemical composition of all kidney stones after spontaneous passage or surgical removal between January 2009 and December 2011 were analyzed according to seasons and corresponding meteorology. A total of 389 stones were analyzed. A higher stone submission rate was observed in summer compared to winter (31.6% vs. 20.8%, P = 0.0008) and in the warm period compared to the cold period (57.1% vs. 42.9%, P = 0.0001). Significant correlation was established between the monthly number of stones and mean monthly maximum temperature (r = 0.50, P = 0.002), mean monthly temperature (r = 0.49, P = 0.003) and mean monthly Humidex (r = 0.49, P = 0.007). Humidex was found to be an independent predictor for stone submission (β = 0.49, P = 0.007). The majority of stones contained calcium (83.3%), combined with oxalate (77.6%), phosphate (14.7%), and carbonate (2.8%). Some stones (11.8%) contained a mixture of >1 negatively charged molecules. Urate (11.6%), cysteine (4.6%), and ammonium-magnesium-phosphate (0.5%) constituted the rest. There was no association between chemical composition and seasons. Literature review included 25 articles. Higher ambient temperature and warm seasons were the most commonly encountered risk factors for both presentation and etiology of nephrolithiasis. A significant positive correlation was noted between ambient temperature and stone submission rate, which was significantly higher during the warm months in Malta.

Increased dietary long-chain polyunsaturated fatty acids alter serum fatty acid concentrations and lower risk of urine stone formation in cats.

PubMed

Hall, Jean A; Brockman, Jeff A; Davidson, Stephen J; MacLeay, Jen M; Jewell, Dennis E

2017-01-01

The lifespan of cats with non-obstructive kidney stones is shortened compared with healthy cats indicating a need to reduce stone formation and minimize chronic kidney disease. The purpose of this study was to investigate the effects of increasing dietary polyunsaturated fatty acids (PUFA) on urine characteristics. Domestic-short-hair cats (n = 12; mean age 5.6 years) were randomized into two groups and fed one of two dry-cat foods in a cross-over study design. For one week before study initiation, all cats consumed control food that contained 0.07% arachidonic acid (AA), but no eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). Group 1 continued eating control food for 56 days. Group 2 was fed test food for 56 days, which was control food plus fish oil and high-AA oil. Test food contained 0.17% AA, 0.09% EPA and 0.18% DHA. After 56 days, cats were fed the opposite food for another 56 days. At baseline and after each feeding period, serum was analyzed for fatty acid concentrations, and urine for specific gravity, calcium concentration, relative-super-saturation for struvite crystals, and a calcium-oxalate-titrimetric test was performed. After consuming test food, cats had increased (all P<0.001) serum concentrations of EPA (173%), DHA (61%), and AA (35%); decreased urine specific gravity (P = 0.02); decreased urine calcium concentration (P = 0.06); decreased relative-super-saturation for struvite crystals (P = 0.03); and increased resistance to oxalate crystal formation (P = 0.06) compared with cats consuming control food. Oxalate crystal formation was correlated with serum calcium concentration (r = 0.41; P<0.01). These data show benefits for reducing urine stone formation in cats by increasing dietary PUFA.

Increased dietary long-chain polyunsaturated fatty acids alter serum fatty acid concentrations and lower risk of urine stone formation in cats

PubMed Central

Brockman, Jeff A.; Davidson, Stephen J.; MacLeay, Jen M.; Jewell, Dennis E.

2017-01-01

The lifespan of cats with non-obstructive kidney stones is shortened compared with healthy cats indicating a need to reduce stone formation and minimize chronic kidney disease. The purpose of this study was to investigate the effects of increasing dietary polyunsaturated fatty acids (PUFA) on urine characteristics. Domestic-short-hair cats (n = 12; mean age 5.6 years) were randomized into two groups and fed one of two dry-cat foods in a cross-over study design. For one week before study initiation, all cats consumed control food that contained 0.07% arachidonic acid (AA), but no eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). Group 1 continued eating control food for 56 days. Group 2 was fed test food for 56 days, which was control food plus fish oil and high-AA oil. Test food contained 0.17% AA, 0.09% EPA and 0.18% DHA. After 56 days, cats were fed the opposite food for another 56 days. At baseline and after each feeding period, serum was analyzed for fatty acid concentrations, and urine for specific gravity, calcium concentration, relative-super-saturation for struvite crystals, and a calcium-oxalate-titrimetric test was performed. After consuming test food, cats had increased (all P<0.001) serum concentrations of EPA (173%), DHA (61%), and AA (35%); decreased urine specific gravity (P = 0.02); decreased urine calcium concentration (P = 0.06); decreased relative-super-saturation for struvite crystals (P = 0.03); and increased resistance to oxalate crystal formation (P = 0.06) compared with cats consuming control food. Oxalate crystal formation was correlated with serum calcium concentration (r = 0.41; P<0.01). These data show benefits for reducing urine stone formation in cats by increasing dietary PUFA. PMID:29073223

Determination of urine oxalate level in rats with renal calcium oxalate calculus by high-performance liquid chromatography.

PubMed

Cao, Qiu-shi; Ba, Yuan-ming; Luo, Jun-hua; Dai, Qi

2015-02-01

To establish a method of high-performance liquid chromatography (HPLC) for determining the urine oxalate levle in rats with renal calcium oxalate calculus. Totally 24 SPF Wistar healthy male rats were randomly divided into control group(n=12)and ethylene glycol (EG) group (n=12). Rats in EG group were administered intragastrically with 2% ammonium chloride (AC)2 ml/rat per day+1% ethylene glycol (EG), along with free access to drinking water.The control group was fed with deionized water, along with the intragastric administration of normal saline (1 ml per day). Twenty-eight days after modelling, the 24-hour urine samples were collected, and the urine oxalic acid levels were determined using HPLC and the results were compared with those of catalytic spectrophotometry using oxidation of methyl. During the HPLC, the samples were separated on Aglient 5TC-C18 (250×4.6 mm,5 Μm), eluted with mixture of methanol (0.1 mol/L) and ammonium acetate (15:85) at 1.2 ml/min, and detected at 314 nm, with the column temperature being 20 ℃. The standard curves of high and low concentrations of oxalic acid were y=5909.1x+378730, R² =0.9984 and y=7810.5x-16635, R² =0.9967,respectively. The lowest detectable concentration in this method was 5 Μg/ml. The linear high concentration range of oxalate stood at 62.50-2000.00 Μg/ml, and the linear low concentration range of oxalate stood at 6.25-100.00 Μg/ml. Its average recovery was 95.1%, and its within-day and day-to-day precisions were 3.4%-10.8% and 3.8%-9.4%. Both HPLC and catalytic spectrophotometry showed significantly higher urinary oxalic acid concentration and 24 h urine oxalate level in EG group compared with the control group [urinary oxalic acid concentration: (736.35 ± 254.52) Μg/ml vs.(51.56 ± 36.34) Μg/ml,(687.35 ± 234.53) Μg/ml vs.(50.24 ± 42.34) Μg/ml;24 h urine oxalate level: (11.23 ± 4.12)mg vs.(0.87 ± 0.45)mg,(9.89 ± 3.55)mg vs. (0.77 ± 0.65)mg; all P<0.01]. No statistically significant difference

Incidence and characteristics of kidney stones in patients with horseshoe kidney: A systematic review and meta-analysis

PubMed Central

Pawar, Aditya S.; Thongprayoon, Charat; Cheungpasitporn, Wisit; Sakhuja, Ankit; Mao, Michael A.; Erickson, Stephen B.

2018-01-01

Introduction: The horseshoe kidney (HSK) is the most common type of renal fusion anomaly. The incidence and characteristics of kidney stones in patients with HSK are not well studied. The aim of this meta-analysis was to evaluate the incidence and types of kidney stones in patients with HSK. Methods: A systematic literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from the databases' inception through November 2016. Studies assessing the incidence and types of kidney stones in patients with HSK were included. We applied a random-effects model to estimate the incidence of kidney stones. The study protocol was registered with PROSPERO (International Prospective Register of Systematic Reviews; no. CRD42016052037). Results: A total of 14 observational studies with 943 patients (522 adults and 421 pediatric) with HSK were enrolled. The estimated pooled incidence of kidney stones was 36% (95% confidence interval [CI], 15%–59%) in adults with the HSK. Kidney stones were less common in pediatric patients with HSK with an estimated pooled incidence of 3% (95% CI, 2%–5%). The mean age of adult stone formers with HSK was 44.9 ± 6.2 years, and 75% were males. Within reported studies, 89.2% of kidney stones were calcium-based stones (64.2% calcium oxalate [CaOx], 18.8% calcium phosphate [CaP], and 6.2% mixed CaOx/CaP), followed by struvite stones (4.2%), uric acid stones (3.8%), and others (2.8%). Conclusions: Kidney stones are very common in adult patients with HSK with an estimated incidence of 36%. Calcium-based stones are the most prevalent kidney stones in adults with HSKs. These findings may impact the prevention and clinical management of kidney stones in patients with HSK. PMID:29416282

A multiregional Italian cohort of 24-hour urine metabolic evaluation in renal stone formers.

PubMed

Esperto, Francesco; Marangella, Martino; Trinchieri, Alberto; Petrarulo, Michele; Miano, Roberto

2018-02-01

Nephrolithiasis is a common condition with several studies documenting an increased prevalence over the past four decades. EAU and AUA guidelines recommend 24-hour urine metabolic evaluation in high-risk stone formers. Aim of this study is to retrospectively evaluate the first three years of experience with LithoTest® (Biohealth Italia Srl, Turin, Italy) through the analysis of demographic, clinical and biochemical data collected from a large cohort of patients with kidney stones. We retrospectively analyzed data from the LithoCenter database, including data from outpatient consultations, between January 2007 and December 2009 from all over Italy. LithoTest® was performed through a 24-hour urine collection and included measurements of urine volume and pH, 24-hour excretion of creatinine as well as main cations and anions, including calcium, magnesium sodium potassium, ammonium, uric acid, oxalate, citrate, phosphate, inorganic sulphate and chloride. Urine state of saturation for calcium oxalate (βCaOx), calcium hydrogen phosphate or brushite (βbsh) and uric acid (βUA) were also calculated by means of the computer program LithoRisk. Brand's test for cystinuria was also carried out. Statistical analysis was performed using the S-PSS software v. 22.0. The number of patients with data available for analysis was 435, of whom 236 were male (54%) and 199 female (46%). Complete 24-hour urine measurements were available for all 435 patients. Compared to men, women had significantly lower values for creatinine, urate, oxalate, phosphate, sodium, potassium, magnesium and chloride excretion, whereas 24-hour pH and citrate excretion were higher. No significant differences were found for the other examined variables. βCaOx and βUA were significantly higher in men than women, whereas no significant difference was found for βbsh. There was a direct relationship between calcium and sodium urine excretion. Excessive sodium excretion was recorded in 191 patients (44%) and low

Compositional analysis of various layers of upper urinary tract stones by infrared spectroscopy

PubMed Central

He, Zhang; Jing, Zhang; Jing-Cun, Zheng; Chuan-Yi, Hu; Fei, Gao

2017-01-01

The objective of the present study was to determine the composition of various layers of upper urinary stones and assess the mechanisms of stone nucleation and aggregation. A total of 40 integrated urinary tract stones with a diameter of >0.8 cm were removed from the patients. All of the stones were cut in half perpendicularly to the longitudinal axis. Samples were selected from nuclear, internal and external layers of each stone. Fourier transform infrared spectroscopy (FT-IR) was adopted for qualitative and quantitative analysis of all of the fragments and compositional differences among nuclear, internal and external layers of various types of stone were subsequently investigated. A total of 25 cases of calcium oxalate (CaOx) stones and 10 cases of calcium phosphate (CaP) stones were identified to be mixed stones, while 5 uric acid (UA) calculi were pure stones (purity, >95%). In addition, the contents of CaOx and carbapatite (CA.AP) crystals in various layers of the mixed stones were found to be variable. In CaOx stones, the content of CA.AP in nuclear layers was significantly higher than that of the outer layers (32.0 vs. 6.8%; P<0.05), while the content of CaOx was lower in the inner than in the outer layers (57.6 vs. 86.6%; P<0.05). In CaP stones, the content of CA.AP in the nuclear layers was higher than that in the outer layers (74.0 vs. 47.3%; P<0.05), while the content of CaOx was lower in the inner than in the outer layers (7.0 vs. 40.0%; P<0.05). The UA stones showed no significant differences in their composition among different layers. In conclusion, FT-IR analysis of various layers of human upper urinary tract stones revealed that CaOx and CaP stones showed differences in composition between their core and surface, while all of the UA calculi were pure stones. The composition showed a marked variation among different layers of the stones, indicating that metabolism has an important role in different phases of the evolution of stones. The present

Screening of Indigenous Oxalate Degrading Lactic Acid Bacteria from Human Faeces and South Indian Fermented Foods: Assessment of Probiotic Potential

PubMed Central

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

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

USDA-ARS?s Scientific Manuscript database

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 pos...

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 nanosuspensions for use in a pressurized metered-dose inhaler (pMDI). Sildenafil citrate monohydrate pMDI formulations were prepared by a bottom-up process using dried ethanol as a solvent and HFA-134a as an antisolvent and propellant in order to form nanosuspensions. A 3×3 factorial design was applied for the contents of the dried ethanol and HFA-134a propellant. The phase solubility profiles of the sildenafil and cyclodextrins were described as AL type with a mole ratio 1:1. The piperazine moiety of sildenafil formed an inclusion in the cavity of the CDs. The particle diameters of the sildenafil citrate monohydrate suspensions in pMDIs were all within a nanosuspension size range. An assay of the sildenafil content showed that the formation of complexes with CDs was close to 100%. In the case of the formulations with CDs, the emitted doses varied within 97.4±10.8%, the fine particle fractions (FPFs) were in a range of 45-81%, the fine particle dose (FPD) was 12.6±2.0 μg and the mass median aerodynamic diameters (MMADs) were 1.86±0.41 μm. In contrast, the formulations without CDs produced a low emitted dose of sildenafil (<60%). Therefore, only sildenafil citrate monohydrate pMDI formulations containing CDs were suitable for use as aerosols. Copyright © 2013 Elsevier B.V. All rights reserved.

Phenotypic and functional analysis of human SLC26A6 variants in patients with familial hyperoxaluria and calcium oxalate nephrolithiasis.

PubMed

Monico, Carla G; Weinstein, Adam; Jiang, Zhirong; Rohlinger, Audrey L; Cogal, Andrea G; Bjornson, Beth B; Olson, Julie B; Bergstralh, Eric J; Milliner, Dawn S; Aronson, Peter S

2008-12-01

Urinary oxalate is a major risk factor for calcium oxalate stones. Marked hyperoxaluria arises from mutations in 2 separate loci, AGXT and GRHPR, the causes of primary hyperoxaluria (PH) types 1 (PH1) and 2 (PH2), respectively. Studies of null Slc26a6(-/-) mice have shown a phenotype of hyperoxaluria, hyperoxalemia, and calcium oxalate urolithiasis, leading to the hypothesis that SLC26A6 mutations may cause or modify hyperoxaluria in humans. Cross-sectional case-control. Cases were recruited from the International Primary Hyperoxaluria Registry. Control DNA samples were from a pool of adult subjects who identified themselves as being in good health. PH1, PH2, and non-PH1/PH2 genotypes in cases. Homozygosity or compound heterozygosity for SLC26A6 variants. Functional expression of oxalate transport in Xenopus laevis oocytes. 80 PH1, 6 PH2, 8 non-PH1/PH2, and 96 control samples were available for SLC26A6 screening. A rare variant, c.487C-->T (p.Pro163Ser), was detected solely in 1 non-PH1/PH2 pedigree, but this variant failed to segregate with hyperoxaluria, and functional studies of oxalate transport in Xenopus oocytes showed no transport defect. No other rare variant was identified specifically in non-PH1/PH2. Six additional missense variants were detected in controls and cases. Of these, c.616G-->A (p.Val206Met) was most common (11%) and showed a 30% reduction in oxalate transport. To test p.Val206Met as a potential modifier of hyperoxaluria, we extended screening to PH1 and PH2. Heterozygosity for this variant did not affect plasma or urine oxalate levels in this population. We did not have a sufficient number of cases to determine whether homozygosity for p.Val206Met might significantly affect urine oxalate. SLC26A6 was effectively ruled out as the disease gene in this non-PH1/PH2 cohort. Taken together, our studies are the first to identify and characterize SLC26A6 variants in patients with hyperoxaluria. Phenotypic and functional analysis excluded a

Phenotypic and Functional Analysis of Human SLC26A6 Variants in Patients With Familial Hyperoxaluria and Calcium Oxalate Nephrolithiasis

PubMed Central

Monico, Carla G.; Weinstein, Adam; Jiang, Zhirong; Rohlinger, Audrey L.; Cogal, Andrea G.; Bjornson, Beth B.; Olson, Julie B.; Bergstralh, Eric J.; Milliner, Dawn S.; Aronson, Peter S.

2008-01-01

Background Urinary oxalate is a major risk factor for calcium oxalate stones. Marked hyperoxaluria arises from mutations in two separate loci, AGXT and GRHPR, the causes of primary hyperoxaluria (PH) types 1 and 2, respectively. Studies of null Slc26a6 (−/−) mice have revealed a phenotype of hyperoxaluria, hyperoxalemia and calcium oxalate urolithiasis, leading to the hypothesis that SLC26A6 mutations may cause or modify hyperoxaluria in humans. Study Design Cross-sectional, case-control. Setting & Participants Cases were recruited from the International Primary Hyperoxaluria Registry. Control DNA samples were from a pool of adult subjects who identified themselves as being in good health. Predictor PH1, PH2, non-PH1/PH2 genotypes in cases. Outcomes & Measures Homozygosity or compound heterozygosity for SLC26A6 variants. Functional expression of oxalate transport in Xenopus oocytes. Results A total of 80 PH1, 6 PH2, 8 non-PH1/PH2 and 96 control samples were available for SLC26A6 screening. A rare variant, c.487C>T (p.Pro163Ser) was detected solely in one non-PH1/PH2 pedigree but this variant failed to segregate with hyperoxaluria, and functional studies of oxalate transport in Xenopus oocytes revealed no transport defect. No other rare variant was identified specifically in non-PH1/PH2. Six additional missense variants were detected in controls and in cases. Of these, c.616G>A (p.Val206Met) was most common (11%), and showed a 30% reduction in oxalate transport. To test p.Val206Met as a potential modifier of hyperoxaluria, we extended screening to PH1 and PH2. Heterozygosity for this variant did not affect plasma or urine oxalate in this population. Limitations We did not have a sufficient number of cases to determine whether homozygosity for p.Val206Met might significantly affect urine oxalate. Conclusions SLC26A6 was effectively ruled out as the disease gene in this non-PH1/PH2 cohort. Taken together, our studies are the first to identify and characterize SLC

X-ray diffraction and SEM study of kidney stones in Israel: quantitative analysis, crystallite size determination, and statistical characterization.

PubMed

Uvarov, Vladimir; Popov, Inna; Shapur, Nandakishore; Abdin, Tamer; Gofrit, Ofer N; Pode, Dov; Duvdevani, Mordechai

2011-12-01

Urinary calculi have been recognized as one of the most painful medical disorders. Tenable knowledge of the phase composition of the stones is very important to elucidate an underlying etiology of the stone disease. We report here the results of quantitative X-ray diffraction phase analysis performed on 278 kidney stones from the 275 patients treated at the Department of Urology of Hadassah Hebrew University Hospital (Jerusalem, Israel). Quantification of biominerals in multicomponent samples was performed using the normalized reference intensity ratio method. According to the observed phase compositions, all the tested stones were classified into five chemical groups: oxalates (43.2%), phosphates (7.7%), urates (10.3%), cystines (2.9%), and stones composed of a mixture of different minerals (35.9%). A detailed analysis of each allocated chemical group is presented along with the crystallite size calculations for all the observed crystalline phases. The obtained results have been compared with the published data originated from different geographical regions. Morphology and spatial distribution of the phases identified in the kidney stones were studied with scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). This type of detailed study of phase composition and structural characteristics of the kidney stones was performed in Israel for the first time.

21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

Code of Federal Regulations, 2010 CFR

2010-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A... edible tissues of chickens. ...

21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

Code of Federal Regulations, 2013 CFR

2013-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A... edible tissues of chickens. ...

21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

Code of Federal Regulations, 2014 CFR

2014-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A... edible tissues of chickens. ...

21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

Code of Federal Regulations, 2011 CFR

2011-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A... edible tissues of chickens. ...

21 CFR 556.625 - Sodium sulfachloropyrazine monohydrate.

Code of Federal Regulations, 2012 CFR

2012-04-01

... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for Residues of New Animal Drugs § 556.625 Sodium sulfachloropyrazine monohydrate. A... edible tissues of chickens. ...

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.

THE CORE OF THE PSEUDOSTEM OF MUSA IN THE TREATMENT OF URINARY STONES

PubMed Central

Pillai, R. Gopakumara

1995-01-01

Ayurveda recommends many simple herbs in the treatment of urological afflictions like urolithiasis. Seventyone patients diagnosed to be suffering from urolithiasis were treated with juice of the core of the pseudostem of Musa Paradisiaca and Musa sapientum. A significant segment of them passed out calculi of varying size after consuming the drug for two weeks. Recurrence of stone formation was also prevented by the treatment, The author concludes that the plant material is quite effective in curing urolithiasis, especially of the calcium oxalate variety. PMID:22556713

Crystal growth and physical characterization of picolinic acid cocrystallized with dicarboxylic acids

NASA Astrophysics Data System (ADS)

Somphon, Weenawan; Haller, Kenneth J.

2013-01-01

Pharmaceutical cocrystals are multicomponent materials containing an active pharmaceutical ingredient with another component in well-defined stoichiometry within the same unit cell. Such cocrystals are important in drug design, particularly for improving physicochemical properties such as solubility, bioavailability, or chemical stability. Picolinic acid is an endogenous metabolite of tryptophan and is widely used for neuroprotective, immunological, and anti-proliferative effects within the body. In this paper we present cocrystallization experiments of a series of dicarboxylic acids, oxalic acid, succinic acid, DL-tartaric acid, pimelic acid, and phthalic acid, with picolinic acid. Characterization by FT-IR and Raman spectroscopy, DSC and TG/DTG analysis, and X-ray powder diffraction show that new compounds are formed, including a 1:1 picolinium tartrate monohydrate, a 2:1 monohydrate adduct of picolinic acid and oxalic acid, and a 2:1 picolinic acid-succinic acid monohydrate cocrystal.

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.

Preclinical Evaluation of Antiurolithiatic Activity of Viburnum opulus L. on Sodium Oxalate-Induced Urolithiasis Rat Model

PubMed Central

İlhan, Mert; Ergene, Burçin; Süntar, Ipek; Özbilgin, Serkan; Saltan Çitoğlu, Gülçin; Demirel, M. Ayşe; Keleş, Hikmet; Altun, Levent; Küpeli Akkol, Esra

2014-01-01

The aim of the present research is to evaluate the antiurolithiatic effect of the various extracts prepared from the fruits of Viburnum opulus L., in regard to its ethnobotanical record. To induce urolithiasis, 70 mg/kg sodium oxalate was injected to the rats which were housed individually in metabolic cages. The test materials were applied during 7 days. Biochemical (urine and serum parameters), histopathological and antioxidant (TBARs, TSH and GSH) assays were conducted. The urine samples were examined by light microscope for the determination of the calcium oxalate crystals. Lyophilized juice of V. opulus (LJVO) and lyophilized commercial juice of V. opulus (LCJVO) exerted potential antiurolithiatic activity which was attributed to its diuretic effect along with the inhibitory action on the oxalate levels and free radical production. We also determined the chlorogenic acid content of the LJVO by high-performance liquid chromatography (HPLC). Chlorogenic acid was determined by using Supelcosil LC-18 (250 × 4.6 mm, 5 µm) column and acetonitrile: water: 0.2% o-phosphoric acid as a mobile phase. The chlorogenic acid content of V. opulus was found to be 0.3227 mg/mL in fruit juice. The results obtained in this study have provided a scientific evidence for the traditional usage of V. opulus on passing kidney stones in Turkish folk medicine. PMID:25165481

Focused Ultrasound to Expel Calculi from the Kidney: Safety and Efficacy of a Clinical Prototype Device

PubMed Central

Harper, Jonathan D.; Sorensen, Mathew D.; Cunitz, Bryan W.; Wang, Yak-Nam; Simon, Julianna C.; Starr, Frank; Paun, Marla; Dunmire, Barbrina; Liggitt, H. Denny; Evan, Andrew P.; McAteer, James A.; Hsi, Ryan S.; Bailey, Michael R.

2015-01-01

Purpose Focused ultrasound has the potential to expel small stones or residual stone fragments from the kidney, or move obstructing stones to a nonobstructing location. We evaluated the efficacy and safety of ultrasonic propulsion in a live porcine model. Materials and Methods Calcium oxalate monohydrate kidney stones and laboratory model stones (2 to 8 mm) were ureteroscopically implanted in the renal pelvicalyceal system of 12 kidneys in a total of 8 domestic swine. Transcutaneous ultrasonic propulsion was performed using an HDI C5-2 imaging transducer (ATL/Philips, Bothell, Washington) and the Verasonics® diagnostic ultrasound platform. Successful stone relocation was defined as stone movement from the calyx to the renal pelvis, ureteropelvic junction or proximal ureter. Efficacy and procedure time was determined. Three blinded experts evaluated histological injury to the kidney in the control, sham treatment and treatment arms. Results All 26 stones were observed to move during treatment and 17 (65%) were relocated successfully to the renal pelvis (3), ureteropelvic junction (2) or ureter (12). Average ± SD successful procedure time was 14 ± 8 minutes and a mean of 23 ± 16 ultrasound bursts, each about 1 second in duration, were required. There was no evidence of gross or histological injury to the renal parenchyma in kidneys exposed to 20 bursts (1 second in duration at 33-second intervals) at the same output (2,400 W/cm2) used to push stones. Conclusions Noninvasive transcutaneous ultrasonic propulsion is a safe, effective and time efficient means to relocate calyceal stones to the renal pelvis, ureteropelvic junction or ureter. This technology holds promise as a useful adjunct to surgical management for renal calculi. PMID:23583535

Sulfate but not thiosulfate reduces calculated and measured urinary ionized calcium and supersaturation: implications for the treatment of calcium renal stones.

PubMed

Rodgers, Allen; Gauvin, Daniel; Edeh, Samuel; Allie-Hamdulay, Shameez; Jackson, Graham; Lieske, John C

2014-01-01

Urinary sulfate (SO4(2-)) and thiosulfate (S2O3(2-)) can potentially bind with calcium and decrease kidney stone risk. We modeled the effects of these species on the concentration of ionized calcium (iCa) and on supersaturation (SS) of calcium oxalate (CaOx) and calcium phosphate (CaP), and measured their in vitro effects on iCa and the upper limit of stability (ULM) of these salts. Urine data from 4 different types of stone patients were obtained from the Mayo Nephrology Clinic (Model 1). A second data set was obtained from healthy controls and hypercalciuric stone formers in the literature who had been treated with sodium thiosulfate (STS) (Model 2). The Joint Expert Speciation System (JESS) was used to calculate iCa and SS. In Model 1, these parameters were calculated as a function of sulfate and thiosulfate concentrations. In Model 2, data from pre- and post STS urines were analyzed. ULM and iCa were determined in human urine as a function of sulfate and thiosulfate concentrations. Calculated iCa and SS values for all calcium salts decreased with increasing sulfate concentration. Thiosulfate had no effect on these parameters. In Model 2, calculated iCa and CaOx SS increased after STS treatment, but CaP SS decreased, perhaps due to a decrease in pH after STS treatment. In confirmatory in vitro experiments supplemental sulfate, but not thiosulfate, significantly increased the calcium needed to achieve the ULM of CaP and tended to increase the oxalate needed to reach the ULM of CaOx. Sulfate also significantly decreased iCa in human urine, while thiosulfate had no effect. Increasing urinary sulfate could theoretically reduce CaOx and CaP stone risk. Although STS may reduce CaP stone risk by decreasing urinary pH, it might also paradoxically increase iCa and CaOx SS. As such, STS may not be a viable treatment option for stone disease.

Biochemical risk factors for stone formation in healthy school children.

PubMed

Akhavan-Sepahi, Mohsen; Sharifian, Mostafa; Mohkam, Maasumeh; Vafadar, Mahdi; Hejazi, Shamsaddin

2012-01-01

Prevalence of urolithiasis in childhood is increasing. The wide geographic variation in the incidence of lithiasis in childhood is related to climatic, dietary, and socioeconomic factors. Many children with stone disease have a metabolic abnormality. In Southeast Asia, urinary calculi are endemic and are related to dietary factors. The main aim of this study was to determine the prevalence of renal stone, urine metabolic abnormality, control of blood pressure and demographic character in elementary school children of Qom. A cross sectional study was performed on 110 primary school children (56 girls and 54 boys) aged 7 to 11 years old. Demographic data such as age, height, weight were gathered, and systolic and diastolic blood pressure, Urine analysis and culture, urinary levels of calcium, creatinine, phosphorus, magnesium, sodium, potassium, uric acid, cystine, citrate, oxalate, protein and sonographic findings were evaluated. The mean (±SD) of age was 8.85±1.51 years. Only one child had renal stone (1%), but the prevalence of abnormal renal sonography was 7%. The most prevalent urine metabolic abnormalities were hypercalciuria (23%) and hypocitraturia (100%). 11.2% of children had positive urine culture that all were female. The prevalence of high blood pressure was 7.1% for girls and 11.1% for boys. The prevalence of renal stone in children in this study was 1%, which means the accurate judgment about the prevalence of renal stone in Qom city needs more comprehensive studies. Similar to other studies in Iran this study shows that the prevalence of hypercalciuria is significantly higher comparing to other countries, it may be associated with excessive intake of sodium. © 2012 Tehran University of Medical Sciences. All rights reserved.

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

Evaluating factors that dictate struvite stone composition: A multi-institutional clinical experience from the EDGE Research Consortium.

PubMed

Flannigan, Ryan K; Battison, Andrew; De, Shubha; Humphreys, Mitchell R; Bader, Markus; Lellig, Ekaterina; Monga, Manoj; Chew, Ben H; Lange, Dirk

2018-04-01

Struvite stones account for 15% of urinary calculi and are typically associated with urease-producing urinary tract infections and carry significant morbidity. This study aims to characterize struvite stones based on purity of stone composition, bacterial speciation, risk factors, and clinical features. Retrospective data was collected from patients diagnosed with infection stones between 2008 and 2012. Stone analysis, perioperative urine cultures, bacterial speciation, and clinical data were collected and analyzed. The purity of struvite stones was determined. Statistical comparisons were made among homogeneous and heterogeneous struvite stones. From the four participating centres, 121 struvite stones were identified. Only 13.2% (16/121) were homogenous struvite. Other components included calcium phosphate (42.1%), calcium oxalate (33.9%), calcium carbonate (27.3%), and uric acid (5.8%). Partial or full staghorn calculi occurred in 23.7% of cases. Urease-producing bacteria were only present in 30% of cases. Proteus, E. coli, and Enterococcus were the most common bacterial isolates from perioperative urine, and percutaneous nephrolithotomy was the most common modality of treatment. Only 40% of patients had a urinalysis that was nitrite-positive, indicating that urinalysis alone is not reliable for diagnosing infection stones. The study's limitation is its retrospective nature; as such, the optimal timing of cultures with respect to stone analysis or treatment was not always possible, urine cultures were often not congruent with stone cultures in the same patient, and our findings of E. coli commonly cultured does not suggest causation. Struvite stones are most often heterogeneous in composition. Proteus remains a common bacterial isolate; however, E. coli and Enterococcus were also frequently identified. This new data provides evidence that patients with struvite stones can have urinary tract pathogens other than urease-producing bacteria, thus challenging previous

Evaluating factors that dictate struvite stone composition: A multi-institutional clinical experience from the EDGE Research Consortium

PubMed Central

Battison, Andrew; De, Shubha; Humphreys, Mitchell R.; Bader, Markus; Lellig, Ekaterina; Monga, Manoj; Chew, Ben H.; Lange, Dirk

2018-01-01

Introduction Struvite stones account for 15% of urinary calculi and are typically associated with urease-producing urinary tract infections and carry significant morbidity. This study aims to characterize struvite stones based on purity of stone composition, bacterial speciation, risk factors, and clinical features. Methods Retrospective data was collected from patients diagnosed with infection stones between 2008 and 2012. Stone analysis, perioperative urine cultures, bacterial speciation, and clinical data were collected and analyzed. The purity of struvite stones was determined. Statistical comparisons were made among homogeneous and heterogeneous struvite stones. Results From the four participating centres, 121 struvite stones were identified. Only 13.2% (16/121) were homogenous struvite. Other components included calcium phosphate (42.1%), calcium oxalate (33.9%), calcium carbonate (27.3%), and uric acid (5.8%). Partial or full staghorn calculi occurred in 23.7% of cases. Urease-producing bacteria were only present in 30% of cases. Proteus, E. coli, and Enterococcus were the most common bacterial isolates from perioperative urine, and percutaneous nephrolithotomy was the most common modality of treatment. Only 40% of patients had a urinalysis that was nitrite-positive, indicating that urinalysis alone is not reliable for diagnosing infection stones. The study’s limitation is its retrospective nature; as such, the optimal timing of cultures with respect to stone analysis or treatment was not always possible, urine cultures were often not congruent with stone cultures in the same patient, and our findings of E. coli commonly cultured does not suggest causation. Conclusions Struvite stones are most often heterogeneous in composition. Proteus remains a common bacterial isolate; however, E. coli and Enterococcus were also frequently identified. This new data provides evidence that patients with struvite stones can have urinary tract pathogens other than urease