Urinary Uric Acid Concentrations Research Articles

Effect and Mechanism of Rhein-praseodymium Complex on Intestinal Uric Acid Excretion in Rats with Renal Injury and Hyperuricemia.

Hyperuricemia (HUA) is a disease characterized by excessive uric acid production and/or insufficient uric acid excretion caused by abnormal purine metabolism in the human body. Uric acid deposition caused by hyperuricemia can cause complications, such as kidney damage. The current therapeutic drugs for HUA are not very targeted and usually have specific toxic side effects. This study aimed to synthesize a compound using rhein and praseodymium, which can effectively help hyperuricemia patients with kidney injury to excrete uric acid through the intestine and preliminarily explore its intestinal excretion mechanism. The natural active ingredient rhein and rare earth metal praseodymium were used to synthesize Rh-Pr. The possible chemical structure of Rh-Pr was deduced by UV, IR, 1H-NMR, conductivity method, and thermogravity analysis. Adenine (100 mg/kg) and ethambutol hydrochloride (250 mg/kg) were administered by gavage for three weeks to establish the hyperuricemia rat model of renal injury. Serum uric acid (UA), creatinine (Cr), urea nitrogen (BUN), and uric acid concentration in urine and feces were detected by biochemical methods. The protein expression levels of GLUT9, ABCG2, and MRP4 in the jejunum, ileum, and colon of rats were detected by Western Blotting. According to the characterization, the chemical composition formula of the complex is Pr(C15H7O6)3·2H2O. In vivo, activity tests showed that Rh-Pr could enhance the intestinal uric acid excretion level of rats, upregulate the expression of ABCG2 protein in the jejunum and ileum, down-regulate the expression of GLUT9 protein in the ileum and colon, and also had a good recovery effect on serum uric acid, creatinine, and urea nitrogen levels. Rh-Pr is different from other drugs in that it promotes intestinal uric acid excretion and has a renal recovery effect. It reduces the patient's kidney burden and is significant for hyperuricemia patients with kidney injury.

Effect of the racial group and body condition score at calving on production performance and metabolic profile of buffaloes during the transition period.

This study evaluated the body condition score (BCS) at calving and breed (B) effects on milk composition, yield, performance, physiological parameters, hemogram, blood metabolites, and urinary metabolites in the transition and early lactation periods of Mediterranean (MED) and Murrah (MUR) buffaloes. Twenty MED and fifteen MUR buffaloes were distributed into four experimental treatments, in a completely randomized design, considering their racial groups and BCS (LBCS = low; HBCS = high): LBCS MED (N = 9); HBCS MED (N = 11); LBCS MUR (N = 8); HBCS MUR (N = 7). Animals were monitored during the last 21days of gestation and first 56days postpartum and kept under the same management and feeding conditions. During data collection, milk composition, yield, performance, physiological parameters, hemogram, blood metabolites, and urinary metabolites were evaluated. Higher milk production and fat-corrected milk were observed in MED than MUR buffaloes. Breed effects were observed on body weight, rectal temperature, glucose, urea, calcium (Ca) concentrations, and BCS effects on total protein, albumin, urea, and Ca. There were BCS effects on hematocrit, neutrophils, eosinophils, and interactions between B × BCS for lymphocytes and platelets. There were breed effects on urinary concentrations of chlorine, uric acid, and interactions between weight (W) × B on chlorine and urea. The MED buffaloes can be considered the most prepared to undergo physiological changes, including the BCS value at calving, indicating higher physiological health. Besides, this study demonstrates more considerable preparation for the calving, regardless of the body condition score at calving.

Impact of Hyper- and Hypo-Uricemia on Kidney Function.

Uric acid (UA) forms monosodium urate (MSU) crystals to exert proinflammatory actions, thus causing gout arthritis, urolithiasis, kidney disease, and cardiovascular disease. UA is also one of the most potent antioxidants that suppresses oxidative stress. Hyper andhypouricemia are caused by genetic mutations or polymorphism. Hyperuricemia increases urinary UA concentration and is frequently associated with urolithiasis, which is augmented by low urinary pH. Renal hypouricemia (RHU) is associated with renal stones by increased level of urinary UA, which correlates with the impaired tubular reabsorption of UA. Hyperuricemia causes gout nephropathy, characterized by renal interstitium and tubular damage because MSU precipitates in the tubules. RHU is also frequently associated with tubular damage with elevated urinary beta2-microglobulin due to increased urinary UA concentration, which is related to impaired tubular UA reabsorption through URAT1. Hyperuricemia could induce renal arteriopathy and reduce renal blood flow, while increasing urinary albumin excretion, which is correlated with plasma xanthine oxidoreductase (XOR) activity. RHU is associated with exercise-induced kidney injury, since low levels of SUA could induce the vasoconstriction of the kidney and the enhanced urinary UA excretion could form intratubular precipitation. A U-shaped association of SUA with organ damage is observed in patients with kidney diseases related to impaired endothelial function. Under hyperuricemia, intracellular UA, MSU crystals, and XOR could reduce NO and activate several proinflammatory signals, impairing endothelial functions. Under hypouricemia, the genetic and pharmacological depletion of UA could impair the NO-dependent and independent endothelial functions, suggesting that RHU and secondary hypouricemia might be a risk factor for the loss of kidney functions. In order to protect kidney functions in hyperuricemic patients, the use of urate lowering agents could be recommended to target SUA below 6 mg/dL. In order to protect the kidney functions in RHU patients, hydration and urinary alkalization may be recommended, and in some cases an XOR inhibitor might be recommended in order to reduce oxidative stress.

Label-Free Uric Acid Estimation of Spot Urine Using Portable Device Based on UV Spectrophotometry.

The maintenance of uric acid levels is crucial for the human body. In this study, the feasibility of using portable ultraviolet (UV) spectrophotometry to measure the uric acid of spot urine without the need to add reagents has been demonstrated for the first time. UV spectral analysis has been used to inspect the uric acid concentration in urine. It is found that the absorption spectrum of urine has a high correlation with the concentration of uric acid at a wavelength of around 290–300 nm. Uric acid levels measured with a spectral analyzer compared to uric acid concentrations measured with a traditional biochemical analysis showed good agreement. The portable prototype is label-free and capable of displaying the inspection result of each measurement within 10 s. In the long run, this device can assist people in checking uric acid levels of spot urine with higher frequency and can adjust diet or medication in real time for more efficient health management.

Estimating 24-hour urinary excretion using spot urine measurements in kidney stone formers.

ABSTRACTBackgroundOne limitation of the use of 24-hour collection is impracticality. We analysed the performance of spot urine measurements to estimate 24-hour excretion in patients with kidney stones.MethodsA total of 74 adult patients from two centres performed a 24-hour urine collection. A sample of the last micturition was sent for spot urine analysis. Twenty patients were asked to collect two additional spot urine samples, one before dinner and the other after dinner. Urinary concentrations of creatinine, calcium, oxalate, uric acid, citrate and magnesium were measured in the 24-hour and each of the spot urine samples. Four approaches were used to estimate 24-hour urinary excretion, multiplying the ratio of the spot urinary analyte to creatinine concentration by (i) measured 24-hour urinary creatinine excretion (Prediction 1), (ii) estimated 24-hour urinary creatinine excretion (Prediction 2), (iii) assumed 1-g 24-hour urinary creatinine excretion (Prediction 3) or (iv) assumed 1.5-g 24-hour urinary creatinine excretion (Prediction 4). For each parameter we computed Lin's concordance correlation coefficients (CCCs), Bland–Altman plots and 95% limits of agreement.ResultsThe performance of estimates obtained with Prediction 1 and Prediction 2 was similar, except for citrate and uric acid, for which Prediction 2 performed worse. Both approaches performed moderately well: citrate CCC {0.82 [95% confidence interval (CI) 0.75–0.90]}, oxalate [0.66 (95% CI 0.55–0.78)], magnesium [0.66 (95% CI 0.54–0.77)], calcium [0.63 (95% CI 0.50–0.75)] and uric acid [0.52 (95% CI 0.36–0.68)]. The performance of Predictions 3 and 4 was worse.ConclusionsAlthough spot urine samples may hold promise for clinical and population-based research, at present they have limited utility in clinical practice. Measuring or estimating 24-hour creatinine, rather than assuming a given creatinine excretion, will be necessary in future studies of spot urine samples.

Lactobacillus gasseri PA-3 reduces serum uric acid levels in patients with marginal hyperuricemia

Several studies have reported that Lactobacillus gasseri PA-3 reduces the level of serum uric acid (SUA) in patients with hyperuricemia. However, it remains unknown how PA-3 affects uric acid metabolism. In the present study, we examined effects of PA-3-containing yoghurt on uric acid metabolism in patients with marginal hyperuricemia. Sixteen patients with SUA > 357 μmol/L (marginal hyperuricemia) were enrolled. PA-3-containing yoghurt was administered for 8 weeks. Uric acid metabolism was evaluated just before and 8 weeks after the administration and at 4 weeks after the administration ended (post-administration). SUA levels after the administration were significantly lower than that before the administration and remained low at post-administration. Urinary uric acid concentration (Uur) after the administration were significantly lower than that before the administration. However, post-administration Uur levels were comparable to those before the administration. Therefore, PA-3-containing yoghurt significantly reduced the levels of SUA and Uur in patients with marginal hyperuricemia.

Integrated EC-SERS Chip with Uniform Nanostructured EC-SERS Active Working Electrode for Rapid Detection of Uric Acid.

Toxemia of pregnancy is a very dangerous disease for pregnant women. The mortality rate of toxemia of pregnancy is close to 10% to 15%. Early detection of pregnancy toxemia is to monitoring uric acid concentration in urine. The current mainstream method for detecting uric acid requires an enzyme (urate oxidase), which needs to be stored in a low-temperature environment, and the method requires complex chemical steps, which takes a longer time and more samples. In this study, we propose an integrated miniature three-electrode electrochemical surface-enhanced Raman spectroscopy chip (EC-SERS chip) suitable for rapid EC-SERS detection applications. The integrated microfluidic reservoir on the chip makes it easy to use, which is very suitable for rapid detection applications. The SERS active working electrode for the proposed integrated EC-SERS chip is a nanocone array polycarbonate (PC) substrate decorated with an evenly distributed and tightly packed array of gold nanospheres. It showed good uniformity and can be easily reproduced. The integrated EC-SERS chip is very small compared to the traditional electrochemical cell, which reduces the sample volume required for the testing. In addition, the chip is for one-time use only. It eliminates the need to clean electrochemical cells for reuse, thereby reducing the possibility of contamination and inaccurate detection. Various low-concentration Rhodamine 6G (R6G) solutions were tested to verify the performance of the developed EC-SERS chip. Experimental results showed that the proposed EC-SERS chip has a strong enhancement factor of up to 8.5 × 106 and a very good EC-SERS uniformity (the relative standard deviation of EC-SERS intensity is as low as 1.41%). The EC-SERS chip developed has been further tested for the detection of uric acid in synthetic urine. The results showed that the EC-SERS signal intensity has a highly linear relationship with the logarithm of the uric acid concentration in synthetic urine, which indicates that the developed EC-SERS chip is suitable for the quantitative detection of uric acid in synthetic urine. Therefore, the developed EC-SERS chip is very promising to be used in routine and early diagnosis of pregnancy toxemia and may be used in many other medical tests, food safety, and biotechnology applications.

Dynamics of Restoration of Functional State of the Kidney Parenchyma and Normalization of Main Risk Factors of Calcium-oxalate Nephrolithiasis in Urine on the Background of Using Complex Metaphylaxis

The objective: to investigate the dynamics of restoration of the functional state of the renal parenchyma by levels of N-acetyl-β-D-glucosaminidase (NAG) activity in urine and normalization of the main risk factors of calcium-oxalate nephrolithiasis (Ca-Ox NL) – by concentrations of calcium, oxalic and uric acids in urine on the background of application of complex metaphylaxis within a year after stone removal.Materials and methods. 45 patients with Ca-Ox NL before and after the removal of concrements in 1, 3, 6 and 12 months on the background of the use of complex metaphylaxis were examined. The activity of the conditionally renospecific enzyme NAG and concentration of calcium, oxalic and uric acids were analyzed. The personification of metaphylactic measures was performed depending on the characteristics of the risk factors for the development of Ca-Ox NL: the combination of hyperoxaluria with hyperuricemia and hyperuricuria, the combination of hyperoxaluria with hyperuricemia, the presence of significant hyperoxaluria on the background of normouricemia and normouricuria and also depending on hypercalciuria. The control group consisted of 28 practically healthy persons with normal analysis of urine and free of renal diseases.Results. In patients with NL before the removal of the stone, the activity of NAG, calcium, oxalic and uric acid concentrations probably exceeded the control data. In the dynamics of observation there is a gradual decrease in urinary NAG activity, calcium, oxalic and uric acid concentrations. NAG activity and uric acid concentration did not differ from the data in the control group after 12 months, calcium – after 3 months, oxalic acid concentration after 6 months.Conclusion. Restoration of the functional state of tubular nephrotheoia and normalization of concentrations of the main risk factors for the development of Ca-Ox NL on the background of complex metaphylaxis was achieved in almost 95 % of cases. The obtained results can be used to correct and optimize the treatment tactics of patients with Ca-Ox NL after removal of the calculus during the year.

Interaction of dietary rumen undegradable protein level and supplemental rumen-protected conjugated linoleic acid on performance of growing goat kids

Abstract This study aimed to investigate the effects of dietary rumen undegradable protein (RUP) level and supplemental rumen protected conjugated linoleic acid (rpCLA) on performance, nutrient digestibility, rumen fermentation, urinary purine derivatives and plasma metabolites in growing kids. Thirty-two Kurdish kids (13.06 ± 1.08 kg BW) were fed diets differing in RUP level (low = 250 vs. high = 350 g/kg of dietary CP) supplemented either with 15 g/kg rpCLA or 12 g/kg of hydrogenated soybean oil (HSO). The experiment was lasted for 100 days including a 20-d of adaptation period. Goat kids fed diet containing high RUP supplemented with rpCLA had the lowest dry matter intake, but the greatest average daily gain and feed efficiency compared to the other groups (P ≤ 0.05). The interaction of dietary RUP level and rpCLA supplementation had no effect on organic matter, crude protein and ether extract digestibility and ruminal fermentation parameters (P > 0.05). Goat kids fed diet containing high RUP supplemented with HSO had the greatest plasma concentration of triglycerides compared to the other groups (P ≤ 0.05). Urinary uric acid and allantoin concentrations were not influenced by the experimental diets (P > 0.05). In conclusion, feeding diet containing high RUP level supplemented with 15 g/kg rpCLA improved production performance of growing goat kids.

Mangiferin Ameliorates Hyperuricemic Nephropathy Which Is Associated With Downregulation of AQP2 and Increased Urinary Uric Acid Excretion.

Hyperuricemia is characterized by abnormally high level of circulating uric acid in the blood and is associated with increased risk of kidney injury. The pathophysiological mechanisms leading to hyperuricemic nephropathy (HN) involve oxidative stress, endothelial dysfunction, inflammation, and fibrosis. Mangiferin is a bioactive C-glucoside xanthone, which has been exerting anti-inflammatory, anti-fibrotic, and antioxidative effects in many diseases. This study aimed to evaluate the effect of mangiferin treatment in HN. In a mouse model of HN, we observed lower circulating urate levels and ameliorated renal dysfunction with mangiferin treatment, which was associated with reduced renal inflammation and fibrosis. We next investigated the mechanism of urate lowering effect of mangiferin. Metabolic cage experiment showed that mangiferin-administrated mice excreted significantly more urinary uric acid due to elevated urine output, but no marked change in urine uric acid concentration. Expressions of water channels and urate transporters were further assessed by western blot. Renal AQP2 expression was decreased, yet urate transporters URAT1, GLUT9, and OAT1 expressions were not affected by mangiferin in HN mice. Moreover, mangiferin treatment also normalized xanthine oxidase and SOD activity in HN mice, which would decrease uric acid synthesis and improve oxidative stress, respectively. Therefore, our results reveal a novel mechanism whereby mangiferin can reduce serum uric acid levels by promoting AQP2-related urinary uric acid excretion. This study suggested that mangiferin could be a multi-target therapeutic candidate to prevent HN via mechanisms that involve increased excretion and decreased production of uric acid and modulation of inflammatory, fibrotic, and oxidative pathways.

Protective effects of spirulina against hemato-biochemical alterations, nephrotoxicity, and DNA damage upon lead exposition.

The current study was aimed at exploring the protective efficacy of spirulina against the hemato-biochemical alterations and nephrotoxicity induced by lead (Pb). Female rats aged 12 weeks were treated for 4 weeks with Pb (0.344 g kg-1 bw) associated or not with spirulina (5.3 g kg-1 bw). Renal damage induced by Pb was related to a severe anemia, increases of oxidative stress-related parameters (thiobarbituric acid reactive substances (TBARS) (+29%), protein carbonyl (PCO) (+66.3%), and advanced oxidation protein product (AOPP) (+110%)), plasma lactate dehydrogenase (LDH) (+80%), creatinine and urea levels in plasma, and uric acid concentration in urine, as well as genotoxic changes (+89.3% and +60% for DNA and mRNA levels, respectively). Conversely, LDH and antioxidant enzyme activities in kidney were decreased, as well as the levels of plasma uric acid, and urinary creatinine and urea levels. Spirulina-supplemented rats exhibited normal peripheral blood and renal parameters and renal histology. It can be suggested that Arthrospira platensis alleviates damages induced by Pb, thanks to its high phenolic content and antioxidant capacity.

Novel sonochemical synthesis of Fe3O4 nanospheres decorated on highly active reduced graphene oxide nanosheets for sensitive detection of uric acid in biological samples.

In this study, a super-active Iron (II, III) oxide nanospheres (Fe3O4 NPs) decorated reduced graphene oxide (rGOS) nanocomposite was developed. Fe3O4 NPs were stabilized on rGOS through electrostatic interactions in the aqueous medium. This process involves an ultrasound assisted reduction reaction of the GOS. The as-synthesized Fe3O4 NPs@rGOS was characterized through the HRTEM, SEM, XRD, Raman, elemental mapping and EDX analysis. The Fe3O4 NPs@rGOS modified GCE was developed for the determination of biomarker. Uric acid is important biomarker based on gout and kidney stone with high adverse effect in human body. The results obtained showed that the modified electrode Fe3O4 NPs@rGOS shows good electrochemical reduction peak compared to bare electrode and control electrodes. The Fe3O4 NPs@rGOS modified sensor linear range 0.02-783.6 µM was observed with nanomolar LOD 0.12 nM. In addition, the modified Fe3O4 NPs@rGOS/GCE sensor has been applied to determination of uric acid concentration in urine and blood serum samples. Furthermore, advantages of the modified sensor are high stability, repeatability and reproducibility.

Developing Paper Based Diagnostic Technique to Detect Uric Acid in Urine.

Urinary or serum uric acid concentration is an indicator of chronic kidney condition. An increase in uric acid concentration may indicate renal dysfunction. Reliable instantaneous detection of uric acid without requiring sophisticated laboratory and analytical instrumentation, such as: chromatographic and spectrophotometric methods, would be invaluable for patients with renal complication. This paper reports the early development of a simple, low-cost, instantaneous and user-friendly paper based diagnostic device (PAD) for the qualitative and quantitative detection of uric acid in urine. A colorimetric detection technique was developed based on the intensity of Prussian blue color formation on paper in presence of uric acid; the reaction rate of corresponding chemical reactions on paper surface was also studied. Based on the colorimetric signal produced on paper surface, a calibration curve was developed to detect unknown concentration of uric acid in urine. The effect of temperature on formation of color signal on paper surface was also analyzed. In this study, estimation of urinary uric acid using MATLAB coding on a windows platform was demonstrated as the use of software application and digital diagnostics. This paper-based technique is faster and less expensive compared to traditional detection techniques. The paper-based diagnostic can be integrated with a camera of smart phone, tablet computer or laptop and an image processing application (using windows/android/IOS platform) as a part of digital diagnostics. Therefore, with proper calibration, the paper-based technique can be compatible and economical to the sophisticated detection techniques used to detect urinary uric acid.

The polymorphism rs35767 at IGF1 locus is associated with serum urate levels

Previous studies suggested that the IGF-1/IGF-1 receptor signaling pathway may contribute to regulate uric acid levels. To confirm this hypothesis, we assessed the effects of the IGF-1-raising genetic variant rs35767 on urate levels in serum and urine, and we investigated IGF-1 ability to modulate the expression of transporters involved in reabsorption and secretion of uric acid in the kidney. The study population included 2794 adult Whites. 24-hour urinary uric acid concentration was available for 229 subjects. rs35767 polymorphism was screened using TaqMan genotyping assays. HEK293 (human embryonic kidney-293) cell line was treated with IGF-1 (1, 5, 10, 50 nM) for 24-hours, and differences in the expression of urate transporters were evaluated via Western Blot and real time rtPCR. Individuals carrying the IGF-1-raising allele (rs35767 T) exhibited significantly lower levels of serum urate according to both additive and recessive models, after correction for gender, age, BMI, glucose tolerance, glomerular filtration rate, and anti-hypertensive treatment. TT genotype carriers displayed higher uricosuria than C allele carriers did, after adjusting for confounders. Exposure of HEK293 cells to IGF-1 resulted in a dose-dependent increase of uric acid transporters deputed to uric acid excretion (MRP4, NPT1 and BCRP), and reduction of GLUT9 expression, the major mediator of uric acid reabsorption, both at mRNA and protein level. We observed a significant association between the functional polymorphism rs35767 near IGF1 with serum urate concentrations and we provide a mechanistic explanation supporting a causal role for IGF-1 in the regulation of uric acid homeostasis.

MP31-19 THE IMPACT OF TWENTY-FOUR HOUR URINE STUDY ON STENT EARLY ENCRUSTATION (SEE)

You have accessJournal of UrologyStone Disease: Medical & Dietary Therapy II1 Apr 2018MP31-19 THE IMPACT OF TWENTY-FOUR HOUR URINE STUDY ON STENT EARLY ENCRUSTATION (SEE) Daniel Rittenberg, William Berg, Yefim Sheynkin, Scott Herfel, and David Schulsinger Daniel RittenbergDaniel Rittenberg More articles by this author , William BergWilliam Berg More articles by this author , Yefim SheynkinYefim Sheynkin More articles by this author , Scott HerfelScott Herfel More articles by this author , and David SchulsingerDavid Schulsinger More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.1048AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Stent Early Encrustation (SEE) presents a complicated technical challenge. We sought to examine and characterize differences in twenty-four hour urine (TFHU) studies between encrusters and non-encrusters. METHODS An IRB approved prospective study identified patients with SEE, defined as a calcified stent identified within 3 months of stent placement. From June 2016 to November 2017, patients with indwelling ureteral stents were evaluated for SEE upon exchange or removal and compared to patients without SEE. Demographic data and culture data were evaluated. TFHU studies were examined and compared between these two groups. RESULTS There were fifteen cases of SEE identified. The average age was 48 years old, with 53% being female. Thirteen patients screened were identified as non-encrusters, 42% of which were female, with an average age of 54 years. Non SEE patients were found to have statistically significant higher urinary concentrations of uric acid (0.729 vs 0.460 g/day, p = 0.05), sulfate (43.2 vs 20.0 mEq/day, p = 0.02), magnesium (115.1 vs 57.2 mg/day, p = 0.01), ammonium (44.6 vs 22.0 mmol/day, p = 0.02), and total creatinine (1954.9 vs 1157.2 mg/day, p = 0.03). Additionally, when compared to SEE, non SEE patients had a trend towards significance in total urine volume (2.253 vs 1.344 liters, p = 0.06) and urinary citrate (654.2 vs 374.8, p = 0.08. CONCLUSIONS Non SEE patients were found to have a significantly higher concentration of stone inhibitors. Additionally, urine volume and urinary citrate, were higher in the non SEE patients, although not statistically significant. Further investigation into concentrations of these stone inhibitors may lead to future development of ureteral stent composition to prevent SEE. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e419 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Daniel Rittenberg More articles by this author William Berg More articles by this author Yefim Sheynkin More articles by this author Scott Herfel More articles by this author David Schulsinger More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

SUHU PENYIMPANAN KREATININ DAN ASAM URAT DALAM AIR KEMIH SELAMA 24 JAM

Creatinine and uric acid is a product that excreted in the urine by normal kidney functions. The examination of creatinine and uricacid in urine is done on 24-hour urine collection. During the storage of the urine, it is recommended to be stored in a refrigerator withthe grade temperatures ranging from 2–8°C and is not recommended to use any preservative for the examination of creatinine anduric acid in urine. To know the comparation of creatinine and uric acid concentrations in urine between the urine tested immediatelyafter the collection with urine that was stored at a temperature 2–8°C and those at room temperature for 24 hours. A total of 45 urinesamples from outpatient clinic that came to the laboratory, were collected in particular urine vacutainer. Each urine sample is divided intothree tubes. The first tube (P1) examined concentrations of creatinine and uric acid immediately after collection, was considered as thebaseline value. The second tube (P2) stored at 2–8°C and the third tube (P3) is stored at room temperature for 24 hours, then followedby the examination of creatinine and uric acid concentrations. The examination of creatinine in urine was using reagent CREP2 RocheDiagnostic and uric acid in urine was using reagent UA2 Roche diagnostics by Cobas Integra ® 400 plus ® instrument. The mean ofcreatinine in urine concentrations which immediately examined (P1) is (125.10±74.85 mg/dL), concentrations after storage at 2−8°C(P2) and at room temperature (P3) were (123.42±73.80 mg/dL) and (124.09±73.95 mg/dL) respectively. Based on the analysis ofone-way ANOVA, there were no significant differences between the concentrations of creatinine in urine immediately checked which werestored at 2–8°C and at room temperature (P>0.05). The mean of uric acid in urine concentrations which immediately examined (P1) is(52.61±35.48 mg/dL), where as after storage at 2–8°C (P2) and room temperature (P3) were (45.11±31.62 mg/dL) and (46.38±28.91mg/dL) respectively. Based on the analysis of one-way ANOVA, there were no significant differences between the concentrations of uricacid in urine immediately checked by those stored at 2–8°C and at room temperature (P>0.05). Based on this study, it can be concludedthat there were no effect of storage temperature on the concentrations of creatinine and uric acid in urine within 24 hours.

Hypouricemic Activity of Pentopetia Androsaemifolia Decne. (Apocynaceae) Hydro Alcoholic Extract in Mice

The aim of this work was to investigate the uricemic and uricosuric activity of the hydro alcoholic extract of Pentopetia androsaemifolia in experimentally induced hyperuricemic mice. Hyperuricemia was induced in the mice by intraperitoneal injection of potassium oxonate. Oral administration of the extract at doses 50 to 200 mg/kg reduce hyperuricemia from 218.78 ± 7.50 to 72.29 ± 16.88 mg/l (P< 0. 05). The same doses of 50 to 200 mg/kg of the extract also reduce uricosuria from 125.4 ± 4.4 to 70 ± 12.6 mg/l (p< 0.05). A direct correlation exists between plasma uric acid concentration and urine uric acid concentration (r = 0.99). The hypouricemic activity of the extract could be due to xanthine oxidase inhibition by the flavonoids present in the extract.

Uric acid and blood pressure: exploring the role of uric acid production in The Maastricht Study.

Accumulation of reactive oxygen species by increased uric acid production has been suggested as a possible underlying mechanism for the association between uric acid and high blood pressure (BP). We, therefore, investigated the association between serum uric acid concentration and 24-h urinary uric acid excretion, as proxy for uric acid production, with ambulatory 24-h blood pressure and hypertension. Cross-sectional analyses were conducted among 2555 individuals [52% men, mean age 60.0 ± 8.2 years; 27% type 2 diabetes (by design)] from The Maastricht Study. Multivariable regression analyses were performed to investigate the association of serum uric acid and 24-h urinary uric acid excretion with 24-h pulse pressure, 24-h mean arterial pressure (MAP), and hypertension. After adjustment for traditional hypertension risk factors, serum uric acid concentration (per SD of 81 μmol/l) was associated with higher 24-h MAP [β 0.63 mmHg; confidence interval (CI) 0.27-1.00] and positively associated with hypertension (odds ratio 1.43; CI 1.27-1.61). Urinary uric acid excretion (per SD of 140 mg/day/1.73 m) was associated with higher 24-h MAP (β 0.79 mmHg; CI 0.46-1.12) and with hypertension (odds ratio 1.13; CI 1.02-1.25). There was no significant association between serum and 24-h urinary uric acid excretion with 24-h pulse pressure. There was no interaction with sex or age for the aforementioned associations. Higher serum and urinary uric acid concentrations were associated with higher 24-h MAP and hypertension. These results suggest that serum and 24-urinary uric acid concentrations, the latter as proxy for uric acid production are, independent of each other, associated with BP and hypertension.

Preventive Kidney Stones: Continue Medical Education.

Nephrolithiasis is a common health problem across the globe with a prevalence of 15%–20%. Idiopathic hypercalciuria is the most common cause of nephrolithiasis, and calcium oxalate stones are the most common type of stones in idiopathic hypercalciuric patients. Calcium phosphate stones are frequently associated with other diseases such as renal tubular acidosis type 1, urinary tract infections, and hyperparathyroidism. Compared with flat abdominal film and renal sonography, a noncontrast helical computed tomography scan of the abdomen is the diagnostic procedure of choice for detection of small and radiolucent kidney stones with sensitivity and specificity of nearly 100%. Stones smaller than 5 mm in diameter often pass the urinary tract system and rarely require surgical interventions. The main risk factors for stone formation are low urine output, high urinary concentrations of calcium, oxalate, phosphate, and uric acid compounded by a lower excretion of magnesium and citrate. A complete metabolic workup to identify the risk factors is highly recommended in patients who have passed multiple kidney stones or those with recurrent disease. Calcium oxalate and calcium phosphate stones are treated by the use of thiazide diuretics, allopurinol, and potassium citrate. Strategies to prevent kidney stone recurrence should include the elimination of the identified risk factors and a dietary regimen low in salt and protein, rich in calcium and magnesium which is coupled with adequate fluid intake.

Evaluation of dogs with genetic hyperuricosuria and urate urolithiasis consuming a purine restricted diet: a pilot study.

BackgroundUrate urolithiasis is a common problem in breed homozygous for the mutation that results in hyperuricosuria. Low purine diets have been recommended to reduce purine intake in these dogs.MethodsA higher protein, purine restricted diet with water added was evaluated in dogs with genetic hyperuricosuria and a history of clinical urate urolithiasis over a one year time period. Dogs were evaluated at baseline and 2, 6, and 12 months after initiating the test diet. Bloodwork, urinalysis, abdominal ultrasound, body composition, and 24-h urinary purine metabolite analyses were performed.ResultsTransient, mild, self-limited lower urinary tract signs were noted in only one dog on a single day, despite variable but usually mild and occasionally moderate amounts of echogenic bladder stones (<2-3 mm in size) in almost every dog at each visit. No significant differences were noted in urine specific gravity, urine pH, lean body condition score or body composition. Urinary uric acid concentration was lower on the test diet (p = 0.008), but 24-h uric acid excretions were similar (p = 0.220) compared to baseline. Significant differences between least squares mean plasma amino acid concentrations measured at the 0 and 12-month visits were found only for valine (p = 0.0119) and leucine (p = 0.0017).ConclusionThis study suggests the use of a low purine, higher protein diet with added water may be beneficial as part of the management of dogs with genetic hyperuricosuria and history of clinical urate urolithiasis.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-017-0958-y) contains supplementary material, which is available to authorized users.