Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by UA

  • ua concentration
  • ua level

  • Selected Abstracts

    Assessment of endothelial function and blood metabolite status following acute ingestion of a fructose-containing beverage

    ACTA PHYSIOLOGICA, Issue 1 2010
    A. J. Bidwell
    Abstract Aim:, Fructose intake has increased concurrent with sugar intake and this increase has been implicated in contributing to the development of metabolic syndrome risk factors. Recent evidence suggests a role for uric acid (UA) as a potential mediator via suppression of nitric oxide (NO) bioavailability. The aim of this study was to explore this hypothesis by measuring changes in UA concentration and systemic NO bioavailability as well as endothelial function in response to acute ingestion of a glucose-fructose beverage. Methods:, Ten young (26.80 4.80 years), non-obese (body mass index: 25.1 2.55 kg m,2; percent body fat: 13.5 6.9%) male subjects ingested either a glucose (100 g dextrose in 300 mL) or isocaloric glucose-fructose (glucose : fructose; 45 : 55 g in 300 mL) beverage. Blood was sampled pre- and every 15-min post-ingestion per 90 min and assayed for glucose, lactate, fructose, total nitrate/nitrate, UA and blood lipids. Forearm blood flow and pulse-wave velocity were recorded prior to and at 30 and 45 min time intervals post-ingestion, respectively, while heart rate, systolic and diastolic blood pressure were recorded every 15 min. Results:, The glucose-fructose ingestion was associated with a significant (P < 0.05) increase in plasma lactate concentration and altered free fatty acid levels when compared with glucose-only ingestion. However, UA was not significantly different (P = 0.08) between conditions (AUC: ,1018 1675 vs. 2171 1270 ,mol L,1 per 90 min for glucose and glucose-fructose conditions respectively). Consequently, no significant (P < 0.05) difference in endothelial function or systemic NO bioavailability was observed. Conclusion:, Acute consumption of a fructose-containing beverage was not associated with significantly altered UA concentration, endothelial function or systemic NO bioavailability. [source]

    Poly(pyridine-3-boronic acid)/Multiwalled Carbon Nanotubes Modified Glassy Carbon Electrodes for Simultaneous Determination of Ascorbic Acid, 3,4-Dihydroxyphenylacetic Acid and Uric Acid

    ELECTROANALYSIS, Issue 19 2010
    Zhijiao Wu
    Abstract Poly(pyridine-3-boronic acid) (PPBA)/multiwalled carbon nanotubes (MWCNTs) composite modified glassy carbon electrode (GCE) was used for the simultaneous determination of ascorbic acid (AA), 3,4-dihydroxyphenylacetic acid (DOPAC) and uric acid (UA). The anodic peaks for AA, DOPAC and UA at the PPBA/MWCNTs/GCE were well resolved in phosphate buffer solution (pH,7.4). The electrooxidation of AA, DOPAC and UA in the mixture solution was investigated. The peak currents increase with their concentrations increasing. The detection limits (S/N=3) of AA, DOPAC and UA are 5,M, 3,M and 0.6,M, respectively. [source]

    Simultaneous Determination of Ascorbic Acid, Dopamine and Uric Acid at Pt Nanoparticles Decorated Multiwall Carbon Nanotubes Modified GCE

    ELECTROANALYSIS, Issue 10 2010
    Zekerya Dursun
    Abstract A modified electrode was fabricated by electrochemically deposition of Pt nanoparticles on the multiwall carbon nanotube covered glassy carbon electrode (Pt nanoparticles decorated MWCNT/GCE). A higher catalytic activity was obtained to electrocatalytic oxidation of ascorbic acid, dopamine, and uric acid due to the enhanced peak current and well-defined peak separations compared with both, bare and MWCNT/GCE. The electrode surfaces were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and electrochemical impedance spectroscopy (EIS). Individual and simultaneous determination of AA, DA, and UA were studied by differential pulse voltammetry. The detection limits were individually calculated for ascorbic acid, dopamine, and uric acid as being 1.910,5,M, 2.7810,8,M, and 3.210,8,M, respectively. In simultaneous determination, LODs were calculated for AA, DA, and UA, as of 210,5,M, 4.8310,8,M, and 3.510,7,M, respectively. [source]

    Silver Doped Poly(L -valine) Modified Glassy Carbon Electrode for the Simultaneous Determination of Uric Acid, Ascorbic Acid and Dopamine

    ELECTROANALYSIS, Issue 5 2010
    Wenna Hu
    Abstract In this paper, a silver doped poly(L -valine) (Ag-PLV) modified glassy carbon electrode (GCE) was fabricated through electrochemical immobilization and was used to electrochemically detect uric acid (UA), dopamine (DA) and ascorbic acid (AA) by linear sweep voltammetry. In pH,4.0 PBS, at a scan rate of 100,mV/s, the modified electrode gave three separated oxidation peaks at 591,mV, 399,mV and 161,mV for UA, DA and AA, respectively. The peak potential differences were 238,mV and 192,mV. The electrochemical behaviors of them at the modified electrode were explored in detail with cyclic voltammetry. Under the optimum conditions, the linear ranges were 3.010,7 to 1.010,5,M for UA, 5.010,7 to 1.010,5,M for DA and 1.010,5 to 1.010,3,M for AA, respectively. The method was successfully applied for simultaneous determination of UA, DA and AA in human urine samples. [source]

    Electroanalysis of Norepinephrine at Bare Gold Electrode Pure and Modified with Gold Nanoparticles and S-Functionalized Self-Assembled Layers in Aqueous Solution

    ELECTROANALYSIS, Issue 13 2009
    Teresa, uczak
    Abstract Gold nanoparticles (Au-NPs), cystamine (CA) and 3,3,-dithiodipropionic acid (DTDPA) modified gold bare electrodes were applied in voltammetric sensors for simultaneous detection of norepinephrine (NEP), ascorbic (AA) and uric (UA) acids. A linear relationship between norepinephrine concentration and current response was obtained in the range of 0.1,,M to 600,,M M with the detection limit ,0.091,,M for the electrodes modified at 2D template and in the range of 0.1,,M to 700,,M M with the detection limit ,0.087,,M for the electrodes modified at 3D template The results have shown that using modified electrodes it is possible to perform electrochemical analysis of norepinephrine without interference of ascorbic and uric acids, whose presence is the major limitation in norepinephrine determination at a bare gold electrode. The modified SAMs electrodes show good selectivity, sensitivity, reproducibility and high stability. [source]

    Differential Pulse Voltammetric Determination of Uric Acid on Carbon-Coated Iron Nanoparticle Modified Glassy Carbon Electrodes

    ELECTROANALYSIS, Issue 10 2008
    Shengfu Wang
    Abstract A carbon-coated iron nanoparticles (CIN, a new style fullerence related nanomaterial) modified glassy carbon electrode (CIN/GCE) has been developed for the determination of uric acid (UA). Electrochemical behaviors of UA on CIN/GCE were explored by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). It was found that the voltammetric response of UA on CIN/GC was enhanced dramatically because of the strong accumulation effect of CIN and the large working area of the CIN/GC electrode. The parameters including the pH of supporting electrolyte, accumulation potential and time, that govern the analytical performance of UA have been studied and optimized. The DPV signal of UA on CIN/GCE increased linearly with its concentration in the range from 5.010,7 to 2.010,5 M, with a detection limit of 1.510,7 M (S/N=3). The CIN/GCE was used for the determination of UA in samples with satisfactory results. The proposed CIN/GCE electrochemical sensing platform holds great promise for simple, rapid, and accurate detection of UA. [source]

    The Electrochemical Properties of Co(TPP), Tetraphenylborate Modified Glassy Carbon Electrode: Application to Dopamine and Uric Acid Analysis

    ELECTROANALYSIS, Issue 5 2006
    Yunlong Zeng
    Abstract We report the combination of the charge repelling property of tetraphenyl-borate (TPB) anion and the electrooxidation catalytic effect of cobalt(II) tetrakisphenylporphyrin (CoTPP) embedded in a sol gel ceramic film to develop a modified glassy carbon electrode (CoTPP-TPB-SGGCE) for the simultaneous determination of dopamine (DA) and uric acid (UA). The optimized CoTPP-TPB-SGGCE shows excellent sensitivity and selectivity for the DA and UA analysis. As high as 2000 fold acceptable tolerance of ascorbic acid (AA) for the determination of trace DA and UA is reached. In the presence of 0.10,mM AA, the linear concentration range for DA is from 6.010,8 to 2.510,5,M, and the detection limit is 2.010,8,M. For UA, the linear concentration range is from 1.010,7 to 3.510,5,M, and the detection limit is 7.010,8,M. Our study has also demonstrated that the novel CoTPP-TPB-SGGCE shows high stability and reliability. For 6.00,,M DA and UA, a total of 12,measurements were taken in one week, and the relative standard deviation is 2.05% and 2.68% respectively. No obvious shift of peak current and peak potential is observed over a three-month lifetime test. The response of the sensor is very quick and response time is approximately 1,s. Satisfactory results are also achieved when the CoTPP-TPB-SGGCEs being used to detect the DA and UA in human urine samples. [source]

    A Selective Voltammetric Method for Uric Acid Detection at a Glassy Carbon Electrode Modified with Electrodeposited Film Containing DNA and Pt-Fe(III) Nanocomposites

    ELECTROANALYSIS, Issue 20 2004
    Shuqing Wang
    Abstract A novel biosensor by electrochemical codeposited Pt-Fe(III) nanocomposites and DNA film was constructed and applied to the detection of uric acid (UA) in the presence of high concentration of ascorbic acid (AA). Based on its strong catalytic activity toward the oxidation of UA and AA, the modified electrode resolved the overlapping voltammetric response of UA and AA into two well-defined peaks with a large anodic peak difference (,Epa) of about 380mV. The catalytic peak current obtained from differential pulse voltammetry (DPV) was linearly dependent on the UA concentration from 3.810,6 to 1.610,4,M (r=0.9967) with coexistence of 5.010,4,M AA. The detection limit was 1.810,6,M (S/N=3) and the presence of 20 times higher concentration of AA did not interfere with the determination. The modified electrode shows good sensitivity, selectivity and stability. [source]

    Gold nanoparticle-enhanced capillary electrophoresis-chemiluminescence assay of trace uric acid

    ELECTROPHORESIS, Issue 15 2009
    Shulin Zhao
    Abstract A sensitive method based on gold nanoparticle-enhanced CE-chemiluminescence (CL) detection was developed for quantifying uric acid (UA) in serum. In this work, gold nanoparticles were added into the running buffer of CE to catalyze the post-column CL reaction between luminol and hydrogen peroxide, achieving highly efficient CL emission. Negative peaks were produced due to the inhibitory effects on CL emission from UA eluted from the electrophoretic capillary. The decrease in CL intensity was proportional to the concentration of UA in the range of 2.510,7,1.010,5,M. Detection limit was 4.610,8,M UA. Ten human serum samples were analyzed by the presented method. Serum level of UA was found to be in the range from 204 to 324,,M for healthy subjects (n=5), and from 464 to 497,,M for diabetic patients (n=5). The two groups were significantly different (p<0.05). The results suggested a potential application of the proposed assay in rapid primary diagnosis of diseases such as diabetes. [source]

    A mutagenic analysis of the RNase mechanism of the bacterial Kid toxin by mass spectrometry

    FEBS JOURNAL, Issue 17 2009
    Elizabeth Diago-Navarro
    Kid, the toxin of the parD (kis, kid) maintenance system of plasmid R1, is an endoribonuclease that preferentially cleaves RNA at the 5, of A in the core sequence 5,-UA(A/C)-3,. A model of the Kid toxin interacting with the uncleavable mimetic 5,-AdUACA-3, is available. To evaluate this model, a significant collection of mutants in some of the key residues proposed to be involved in RNA binding (T46, A55, T69 and R85) or RNA cleavage (R73, D75 and H17) were analysed by mass spectrometry in RNA binding and cleavage assays. A pair of substrates, 5,-AUACA-3,, and its uncleavable mimetic 5,-AdUACA-3,, used to establish the model and structure of the Kid,RNA complex, were used in both the RNA cleavage and binding assays. A second RNA substrate, 5,-UUACU-3, efficiently cleaved by Kid both in vivo and in vitro, was also used in the cleavage assays. Compared with the wild-type protein, mutations in the residues of the catalytic site abolished RNA cleavage without substantially altering RNA binding. Mutations in residues proposed to be involved in RNA binding show reduced binding efficiency and a corresponding decrease in RNA cleavage efficiency. The cleavage profiles of the different mutants were similar with the two substrates used, but RNA cleavage required much lower protein concentrations when the 5,-UUACU-3, substrate was used. Protein synthesis and growth assays are consistent with there being a correlation between the RNase activity of Kid and its inhibitory potential. These results give important support to the available models of Kid RNase and the Kid,RNA complex. [source]

    Is it possible to identify early predictors of the future cost of chronic arthritis?

    The VErA project
    Abstract This study was conducted to identify early predictors of the total cost of inflammatory arthritis (IA). One hundred and eighty patients affected by undifferentiated arthritis (UA) or rheumatoid arthritis (RA) were included in the French Very Early rheumatoid Arthritis (VErA) cohort between 1998 and 2001. Health economic data for 2003 were collected using a patient self-questionnaire. Results were analysed in terms of direct, indirect and total costs in 2003 euros (2003,) for the population as a whole and in diagnostic subgroups. A payor perspective (the French National Health Insurance, in this case) was adopted. Multiple linear regression models were used to identify predictors of total cost from among the criteria assessed on recruitment. Results of the study showed that for the study population as a whole, the mean total cost was ,4700 per patient. The costs attributable to the RA and UA sub-groups were ,5928 and ,2424 per patient, respectively. In a univariate analysis, certain parameters were significantly correlated with a higher cost of illness. In the multivariate analysis, some of these parameters were further identified as being predictive of higher cost. Two strong significant, early predictors of total cost were identified: higher pain (P = 0.002) and the presence of rheumatoid factor (P = 0.004). In the RA sub-group, lower grip strength of the dominant hand (P = 0.039) was another predictor of the illness's subsequent economic impact. In conclusion, our data show that simple clinical and laboratory parameters can be used early in the course of IA to predict the condition's impact on healthcare budgets. [source]

    Astroglia-mediated effects of uric acid to protect spinal cord neurons from glutamate toxicity

    GLIA, Issue 5 2007
    Yangzhou Du
    Abstract Uric acid (UA) has been demonstrated to reduce damage to neurons elicited by oxidative stress. However, our studies utilizing cultures derived from embryonic rat spinal cord indicate that an astroglia-mediated mechanism is involved in the effects of UA to protect neurons from glutamate toxicity. The damage elicted by glutamate to neurons in a mixed culture of spinal cord cells can be reversed by UA. Furthermore, addition of UA after the termination of glutamate exposure suggests that UA plays an active role in mediating neuroprotection rather than purely binding peroxynitrite, as previously thought. Importantly, in pure neuron cultures from the same tissue, UA does not protect against glutamate toxicity. Addition of astroglia to the pure neuron cultures restores the ability of UA to protect the neurons from glutamate-induced toxicity. Our results also suggest that glia provide EAAT-1 and EAAT-2 glutamate transporters to protect neurons from glutamate, that functional EAATs may be necessary to mediate the effects of UA, and that treatment with UA results in upregulation of EAAT-1 protein. Taken together, our data strongly suggest that astroglia in mixed cultures are essential for mediating the effects of UA, revealing a novel mechanism by which UA, a naturally produced substance in the body, may act to protect neurons from damage during insults such as spinal cord injury. 2007 Wiley-Liss, Inc. [source]

    Catalyst-Free Efficient Growth, Orientation and Biosensing Properties of Multilayer Graphene Nanoflake Films with Sharp Edge Planes,

    Nai Gui Shang
    Abstract We report a novel microwave plasma enhanced chemical vapor deposition strategy for the efficient synthesis of multilayer graphene nanoflake films (MGNFs) on Si substrates. The constituent graphene nanoflakes have a highly graphitized knife-edge structure with a 2,3,nm thick sharp edge and show a preferred vertical orientation with respect to the Si substrate as established by near-edge X-ray absorption fine structure spectroscopy. The growth rate is approximately 1.6,m min,1, which is 10 times faster than the previously reported best value. The MGNFs are shown to demonstrate fast electron-transfer (ET) kinetics for the Fe(CN)63,/4, redox system and excellent electrocatalytic activity for simultaneously determining dopamine (DA), ascorbic acid (AA) and uric acid (UA). Their biosensing DA performance in the presence of common interfering agents AA and UA is superior to other bare solid-state electrodes and is comparable only to that of edge plane pyrolytic graphite. Our work here, establishes that the abundance of graphitic edge planes/defects are essentially responsible for the fast ET kinetics, active electrocatalytic and biosensing properties. This novel edge-plane-based electrochemical platform with the high surface area and electrocatalytic activity offers great promise for creating a revolutionary new class of nanostructured electrodes for biosensing, biofuel cells and energy-conversion applications. [source]

    Serum Uric Acid and Lipid Levels While Taking Topiramate for Migraine

    HEADACHE, Issue 7 2008
    Abdulkadir Koer MD
    Objective., Topiramate (TPM) therapies for epilepsy or migraine are long-time therapies with unknown mechanisms and special side effects. TPM influences cholesterol (TC) and lipoprotein serum levels. In addition, TPM may cause uric acid (UA) stone formation. Material and Methods., Serum UA, TC, and triglyceride (TG) levels were measured in 53 migraine patients receiving TPM and in 44 age- and sex-matched controls. Compared with controls, patients on TPM showed significantly higher UA and nonsignificantly higher TC and TG values. We recorded pre- and posttreatment levels of UA, TC, and TG levels in 23 patients. Results., We found increased serum levels of UA with TPM use (P < .01). There was a significant and positive correlation between serum UA levels and male gender (P < .01). The changes in serum UA levels before and after TPM treatment differed significantly (P < .01). Conclusion., Our results suggest a need for monitoring serum UA levels in patients receiving TPM. We should perhaps prescribe a low-UA diet and advice to drink much more water in these patients. [source]

    An effective IPv4,IPv6 translation mechanism for SIP applications in next generation networks

    Whai-En Chen
    Abstract In a next generation network, the IPv6-enabled IP multimedia subsystem (IMS) network may connect to an IPv4 network. When an IPv4/IPv6 dual-stack user equipment (UE) initiates a call by sending an IPv6 SIP INVITE message to an IPv4-only user agent (UA), the call cannot be established correctly. To resolve this problem, the IMS-application layer gateway solution, the redirect solution, and the interactive connectivity establishment solution have been proposed. In this paper, we propose an effective solution where only the IPv6 INVITE message is translated into an IPv4 INVITE message. Upon receipt of the IPv4 200 OK message replied from the IPv4-only UA, the dual-stack UE learns that the correspondent UA supports IPv4-only and utilizes IPv4 instead of IPv6 to send the subsequent SIP messages and real-time transport protocol (RTP) packets. The proposed solution is compared with the existing solutions in terms of network node modification, call setup complexity, and RTP transmission latency. Our study indicates that the proposed solution outperforms the other three solutions in the call setup and the RTP transmission. Copyright 2009 John Wiley & Sons, Ltd. [source]

    Evaluation of the extraction efficiency for polyphenol extracts from by-products of green kiwifruit juicing

    Dongxiao Sun-Waterhouse
    Summary The health benefits of fruits are attributable in part to their bioactive components such as phenolics and pectic polysaccharides. By-products derived from kiwifruit processing can be a good source of such bioactive compounds. Extracts were produced using different concentrations of ethanol in water (0%, 30%, 50%, 74% and 96% v/v) from by-products (skin, residue and pulp) of the green-fleshed kiwifruit (Actinidia deliciosa,Hayward') juicing process. The amounts of phenolic compounds and uronic acid (UA) as well as the phenolic composition in each extract were determined. Results show that different by-products contained different concentrations of phenolics and pectic polysaccharides. Based on total phenolic contents, 96% v/v ethanol appeared to be the best extraction medium. The 30% or 74% ethanolic dilution was the second best medium for phenolic extraction from skin and pulp/residue, respectively. Water was a good medium for extracting satisfactory quantities of phenolics as well as the highest concentration of pectic polysaccharides. Phenolic profiling by high-performance liquid chromatography (HPLC) was used to detect individual phenolic compounds in an extract. Results using HPLC showed that alkali pre-treatment has improved the extraction efficiency of phenolics as a function of alkali concentration, fruit tissue type, extraction media, by-product preparation method, and class of polyphenols. As a result more efficient methods for both extraction and characterisation of polyphenols could be evaluated. [source]

    Determination of glycyrrhetic acid in human plasma by HPLC-MS method and investigation of its pharmacokinetics

    W.-J. Zhao PhD
    Summary Objective:, To develop a high performance liquid chromatography mass spectrometry (HPLC-MS) method for the determination of the glycyrrhetic acid (GA) in human plasma and for the investigation of its pharmacokinetics after the oral administration of 150 mg diammonium glycyrrhizinate test and reference capsule formulations. Methods:, The GA in plasma was extracted with ethyl acetate, separated on a C18 column with a mobile phase of methanol (5 mmol/L ammonium acetate),water (85 : 15, V/V) and analysed using a MS detector. Ursolic acid (UA) was used as internal standard. The target ions were m/z 4695 for GA and m/z 4556 for UA, the fragment voltages were 200 V and 100 V for GA and UA respectively. Results:, The calibration curve was linear over the range of 05,200 ng/mL (r = 09974). The limit of quantification for GA in plasma was 05 ng/mL, the recovery was 760,800%, and the inter- and intra-day relative standard deviations (RSD) were <12%. The pharmacokinetic parameters of GA after a single dose of 150 mg diammonium glycyrrhizinate test and reference were as follows: the half life (t1/2) 965 354 h and 946 285 h, the time to peak concentration (Tmax) 1095 132 h and 1100 130 h, the peak concentration (Cmax) 9557 4306 ng/mL and 10389 4924 ng/mL; the area under time-concentration curve (AUC0,48 and AUC0,,) 128184 52711 ngh/mL and 136774 56327 ngh/mL, 131432 56640 ngh/mL and 139697 63006 ngh/mL. The relative bioavailability of diammonium glycyrrhizinate capsule was 9888 1298%. Conclusion:, The assay was sensitive, accurate and convenient, and can be used for the determination of GA in human plasma. Comparison of the bioavailability and pharmacokinetic profile of GA indicated that the test and reference capsules were bioequivalent. [source]

    Selection of glycoprotein IIb/IIIa inhibitors for upstream use in patients with diabetes experiencing unstable angina or non-ST segment elevation myocardial infarction.

    What have we learned in the last 10 years?
    Summary Coronary disease accounts for the majority of deaths among patients with diabetes and the thrombotic milieu accelerated by diabetes results in unstable angina (UA), non-ST segment elevation myocardial infarction (NSTEMI) or ST-segment elevation myocardial infarction (STEMI) or death. Upstream use of a glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitor with percutaneous coronary intervention (PCI) as part of an early invasive approach is preferred. However substantial numbers of patients present to rural or non-teaching hospitals without immediate access to a catheterization laboratory. Enhanced GP IIb/IIIa receptor mobilization, TXA2 production and platelet activation together present an extensive thrombotic challenge that may not be overcome with current doses of GP IIb/IIIa inhibitors when used without PCI. Heterogeneity of platelet aggregometric analysis may have identified GP IIb/IIIa doses used in clinical trials that may not fully overcome the thrombotic challenge in patients with diabetes. GUSTO-IV ACS failed to demonstrate a difference in mortality when used without PCI. The PURSUIT trial provided evidence that eptifibatide decreases death or non-fatal myocardial infarction (MI) in the main group and in the diabetic subgroup. Reductions in this primary endpoint were driven by the reduction in non-fatal MI. The PRISM and PRISM-PLUS trials demonstrated a reduction in death, MI or refractory ischaemia at 48 h or 7 days in the main cohort but not specifically in patients with diabetes. Data supporting use of GP IIb/IIIa inhibitors are inconsistent, raising the question of whether these agents should be used at all without PCI. Variability in experimental methodology of platelet aggregometry and selection of anticoagulant used during dose finding studies may have generated doses that are insufficient to overcome the thrombotic burden. A new marker of active inflammation, sCD40L is found to be upregulated at subtherapeutic doses of GP IIb/IIIa inhibitors, suggesting that rebound inflammatory processes may partially account for absence of clear evidence of benefit with some GP IIb/IIIa inhibitors in patients with diabetes experiencing UA/NSTEMI. [source]

    Antioxidative and Anti-Inflammatory Protection of Oleanolic Acid and Ursolic Acid in PC12 Cells

    Shih-Jei Tsai
    ABSTRACT:, PC12 cells were used to examine the in vitro antioxidative and anti-inflammatory effects of oleanolic acid (OA) and ursolic acid (UA). PC12 cells were pretreated with OA or UA at 20 and 40 ,M and followed by exposure of hydrogen peroxide (H2O2) or 1-methyl-4-phenylpyridinium ion (MPP+) to induce cell injury. Results showed that H2O2 - or MPP+ -treatment significantly decreased cell viability and increased lactate dehydrogenase (LDH) release (P < 0.05). The pretreatment from OA or UA significantly and concentration-dependently reduced subsequent H2O2 - or MPP+ -induced cell death and LDH release (P < 0.05). Either H2O2 - or MPP+ -treatment significantly increased malonyldialdehyde (MDA) formation, decreased glutathione (GSH) content, and diminished glutathione peroxidase (GPX), catalase, and superoxide dismutase (SOD) activities (P < 0.05). The pretreatment from OA or UA significantly retained GSH, and reversed H2O2 - and MPP+ -induced impairment in catalase and SOD activities (P < 0.05), and decreased MDA formation (P < 0.05). Either H2O2 - or MPP+ -treatment significantly elevated interleukin-6 (IL-6) and tumor necrosis factor (TNF)-, levels (P < 0.05). The pretreatments from OA or UA significantly attenuated subsequent H2O2 - or MPP+ -induced release of IL-6 and TNF-, (P < 0.05). Based on the observed antioxidative and anti-inflammatory activities from OA and UA, these 2 compounds were potent agents against neurodegenerative disorder. [source]

    Original Article: A prospective study of uric acid by glucose tolerance status and survival: the Rancho Bernardo Study

    C. K. Kramer
    Abstract., Kramer CK, von Mhlen D, Jassal SK, Barrett-Connor E (University of California, La Jolla, CA; and Hospital de Clinicas de Porto Alegre, RS, Brazil). A prospective study of uric acid by glucose tolerance status and survival: the Rancho Bernardo Study. J Intern Med 2010. Objectives., Little is known about uric acid (UA) levels and mortality in the context of glycaemia. We examined whether serum UA levels predict all-cause and cardiovascular disease (CVD) mortality differentially in older adults by glucose tolerance status. Design and methods., Between 1984 and 1987, 2342 community-dwelling men and women had an oral glucose tolerance test, UA measurement, and assessment of traditional CVD risk factors. We defined glucose tolerance status as normoglycaemia (NG), pre-diabetes (pre-DM), and type 2 diabetes mellitus (T2DM). Ninety per cent were followed for vital status up to 23 years. Death certificates were coded using the Ninth International Classification of Diseases. Results., Baseline age was 69.5 years; 44.4% were men. At baseline 939 had NG, 957 pre-DM, and 446 T2DM. The mean UA by glucose tolerance status was 327.1, 362.8, and 374.7 ,mol L,1. During follow-up, there were 1318 deaths 46.8% attributed to CVD. In Cox-regression analysis, each 119 ,mol L,1 (2 mg dL,1) increment in UA levels predicted an increased hazard ratio (HR) for all-cause deaths independent of age, smoking, body mass index, alcohol, physical activity, diuretic use and estimated glomerular filtration rate in all groups (NG: HR 1.25 95% CI 1.06,1.47, P =0.005; pre-DM: HR 1.20 95% CI 1.06,1.37, P = 0.04; T2DM: HR 1.20 95% CI 1.01,1.47, P = 0.04). After adjusting for CVD risk factors, the UA association with CVD mortality was significant only in the pre-DM and T2DM groups. Conclusion., All-cause mortality was independently associated with UA in all groups, but UA predicted CVD mortality only in those with abnormal glucose tolerance. [source]

    Role of a Streamer-like Coronary Thrombus in the Genesis of Unstable Angina

    Introduction: It is generally believed that the coronary occlusion occurs at the site of plaque disruption in acute coronary syndromes. An exceptional mechanism of coronary occlusion, namely a streamer-like thrombus (SLT) originating in a nonstenotic lesion extended distally to obstruct a just distal nondisrupted stenotic segment, was found by angioscopy in patients with unstable angina (UA). This study was carried out to examine the incidence of this phenomenon and its relationship to the subtypes of UA. Methods: The culprit coronary artery was investigated by angioscopy in successive 48 patients (mean SE age, 61.0 2.3 years; 10 females and 38 males) with UA. Results: SLT originating in a nonstenotic lesion extended distally, and obstructed the just distal most stenotic segment (DMSS) by its tail in 11 patients (eight with class III and three with class II according to Braunwald's classification). Recurrent anginal attacks were observed in all. The nonstenotic lesion in which the SLT originated was a disrupted yellow plaque in most cases. The SLT was frequently red and yellow in a mosaic pattern, indicating a mixture of fresh thrombus and plaque debris. The plaques that constructed the DMSS were not disrupted. Angiographically, the SLT was not detectable and the entry of the DMSS showed a "tapering" configuration. Conclusions: Obstruction of the DMSS by the tail of SLT originating in a nonstenotic lesion is another mechanism of UA. Therefore, treatment of both the nonstenotic lesion and DMSS is needed to prevent recurrent thrombus formation and consequent reattacks. (J Interven Cardiol 2010;23:216,222) [source]

    Gas phase isomeric differentiation of oleanolic and ursolic acids associated with heptakis-(2,6-di- O -methyl)-,-cyclodextrin by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

    Zhan Yu
    Abstract Oleanolic acid (OA) and ursolic acid (UA) are isomeric triterpenoid compounds with similar pharmaceutical properties. Usually, modern chromatographic and electrophoretic methods are widely utilized to differentiate these two compounds. Compared with mass spectrometric (MS) methods, these modern separation methods are both time- and sample-consuming. Herein, we present a new method for structural differentiation of OA and UA by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) with the association of heptakis-(2,6-di- O -methyl)-,-cyclodextrin (DM-,-CD). Exact MS and tandem MS (MS/MS) data showed that there is no perceptible difference between OA and UA, as well as their ,-cyclodextrin and ,-cyclodextrin complexes. However, there is a remarkable difference in MS/MS spectra of DM-,-CD complexes of OA and UA. The peak corresponding to the neutral loss of a formic acid and a water molecule could only be observed in the MS/MS spectrum of the complex of DM-,-CD : OA. Molecular modeling calculations were also employed to further investigate the structural differences of DM-,-CD : OA and DM-,-CD : UA complexes. Therefore, by employing DM-,-CD as a reference reagent, OA and UA could be differentiated with purely MS method. Copyright 2010 John Wiley & Sons, Ltd. [source]

    Accuracy of prostate radiation therapy using a fiducial point-pair registration technique based on the computer-assisted portal imaging quality assurance program PIPSpro

    Wilmosh Mermershtain
    Summary The aim of this study was to assess portal imaging for quality assurance of patient positioning in external beam radiotherapy. We present a retrospective study of the variability of patient position in the treatment of 34 prostate cancer patients who were treated with whole pelvic irradiation followed by arc therapy or boost field (Series I) and 25 patients treated by ,small' pelvic 4-field box technique (Series II). Weekly anteroposterior-posteranterior (AP-PA) and left-lateral portal images were compared to simulation films by using a fiducial point-pair registration technique based on the computer-assisted portal imaging quality assurance program PIPSpro, developed specifically for the verification of treatment positioning in radiation therapy. Series I consisted of 34 patients and 194 portal films (97 AP-PA and 97 left-lateral). Overirradiated (OA) and underirradiated (UA) areas were computed in terms of percentage of the reference field size. For the AP-PA portals, the average OA was 2.75% and average UA was 2.74%. For left-lateral portals, an average OA of 2.49% and UA of 2.78% were measured. Series II consisted of 25 patients and 194 portal films (98 AP-PA and 96 left-lateral). The average OA was 0.88% and average UA was 0.86% in AP-PA portals, and 1.03 and 0.82% for left-lateral portals, respectively. The accuracy of patient positioning in irradiation of prostate cancer in our institution is in the range of 2.69% for whole pelvic fields and 1.0% for small fields. We conclude that PIPSpro is an effective and useful tool for quality assurance in radiotherapy. [source]

    The anti-arthritic effect of ursolic acid on zymosan-induced acute inflammation and adjuvant-induced chronic arthritis models

    Suk-Yun Kang
    Ursolic acid (UA) is pentacyclic triterpenoic acid that naturally occurs in many medicinal herbs and plants. In this study, we examined the possible suppressive effect of UA extracted from Oldenlandia diffusa on zymosan-induced acute inflammation in mice and complete Freund's adjuvant (CFA)-induced arthritis in rats. UA treatment (per oral) dose-dependently (25,200 mg kg,1) suppressed zymosan-induced leucocyte migration and prostaglandin E2 (PGE2) production in the air pouch exudates. Since the maximal effective dose of UA was 50 mg kg,1 in the zymosan experiment, we used this dose of UA in a subsequent study using an adjuvant-induced rheumatoid arthritis model. UA treatment (50 mg kg,1, per oral, once a day for 10 days) was started from day 12 after adjuvant injection. UA dramatically inhibited paw swelling, plasma PGE2 production and radiological changes in the joint caused by CFA injection. Moreover, UA significantly suppressed the arthritis-induced mechanical and thermal hyperalgesia as well as the spinal Fos expression, as determined by immunohistochemistry, which was increased by CFA injection. In addition, overall anti-arthritic potency of UA was comparable with ibuprofen (100 mg kg,1, oral) while UA did not induce significant gastric lesions as compared with the ibuprofen treatment group. These findings strongly suggest that UA is a useful suppressive compound for rheumatoid arthritis treatment with low risk of gastric problems. [source]

    Determination of uric acid in plasma and allantoic fluid of chicken embryos by capillary electrophoresis

    Jana Mat, kov
    Abstract Capillary electrophoresis with diode array detection (DAD) was used to determine uric acid (UA) in chicken plasma and the allantoic fluid of chicken embryos. Complete separation of uric and ascorbic acids was attained in less than 10 min in the optimized BGE containing 60 mM MES + 30 mM Tris + 0.001% (w/v) polybrene (pH 6.1). The limit of UA detection (0.2 mg/L) was found to be low enough for sensitive analysis of native plasma and allantoic fluid samples. Range of linearity (1,200 mg/L), repeatability for peak area (CV <4.1%) and migration time (CV <2.5%), as well as recovery of UA from biological samples (97,100%), were found to be satisfactory. The method was applied to detect the elevated UA concentrations (hyperuricemia) in chicken embryos with induced unilateral renal agenesis. CE/DAD analysis of the chicken plasma can be carried out with a relatively small volume of samples (1 ,L). [source]

    Electrospun Alginate Nanofibers with Controlled Cell Adhesion for Tissue Engineering,

    Sung In Jeong
    Abstract Alginate, a natural polysaccharide that has shown great potential as a cell scaffold for the regeneration of many tissues, has only been nominally explored as an electrospun biomaterial due to cytotoxic chemicals that have typically been used during nanofiber formation and crosslinking. Alginate cannot be electrospun by itself and is often co-spun with poly(ethylene oxide) (PEO). In this work, a cell adhesive peptide (GRGDSP) modified alginate (RA) and unmodified alginate (UA) were blended with PEO at different concentrations and blending ratios, and then electrospun to prepare uniform nanofibers. The ability of electrospun RA scaffolds to support human dermal fibroblast cell attachment, spreading, and subsequent proliferation was greatly enhanced on the adhesion ligand-modified nanofibers, demonstrating the promise of this electrospun polysaccharide material with defined nanoscale architecture and cell adhesive properties for tissue regeneration applications. [source]

    Does asthma control correlate with quality of life related to upper and lower airways?

    ALLERGY, Issue 6 2009
    A real life study
    Background:, The goal of asthma therapy is to achieve an optimal level of disease control, but the relationship between asthma control, impact of comorbid rhinitis and health related quality of life (HRQoL) in real life remains unexplored. Objective:, The aims of this real life study were to evaluate asthma control, the impact of asthma (with and without rhinitis) on HRQoL, the relationship between asthma control and HRQoL, and the role of rhinitis on asthma control and HRQoL. Methods:, 122 asthma patients completed the Asthma Control Test, Rhinitis Symptoms score (T5SS) and RHINASTHMA. Results:, Asthma control was unsatisfactory (44.27% of uncontrolled patients), as well as HRQoL. Controlled patients controlled showed significantly lower scores in all the RHINASTHMA domains compared to uncontrolled. Irrespective of their level of control, patients with rhinitis symptoms showed worse HRQoL in Upper Airways (UA) (P < 0.0001), Lower Airways (LA) (P < 0.001), and Global Summary (GS) (P < 0.0001). In patients with symptomatic rhinitis, RHINASTHMA were lower in controlled asthma patients (UA P = 0.002; LA P < 0.0001; RAI P < 0.01; GS P < 0.0001). Asthma control was associated with lower T5SS score (P = 0.034). Conclusion:, Asthma control in real life is unsatisfactory. Rhinitis and asthma influence each other in terms of control and HRQoL. The control of rhinitis in asthma patients can lead to an optimization of HRQoL related to the upper airways, while this phenomenon is not so evident in asthma. These results suggest to strengthen the ARIA recommendation that asthma patients must be evaluated for rhinitis and vice versa. [source]

    The relationship between uric acid levels and Huntington's disease progression,

    MOVEMENT DISORDERS, Issue 2 2010
    Peggy Auinger MS
    Abstract Uric acid (UA) may be associated with the progression of Parkinson's disease and related neurodegenerative conditions; however, its association with Huntington's disease (HD) progression has not been explored. A secondary analysis of 347 subjects from the CARE-HD clinical trial was performed to examine the relationship between baseline UA levels and the level of functional decline in HD. Outcomes included change in scores at 30 months for the Unified Huntington's Disease Rating Scale components. There was less worsening of total functional capacity over time with increasing baseline UA levels (adjusted mean worsening in scores: 3.17, 2.99, 2.95, 2.28, 2.21, from lowest to highest UA quintile, P = 0.03). These data suggest a possible association between higher UA levels and slower HD progression, particularly as measured by total functional capacity. If confirmed, UA could be an important predictor and potentially modifiable factor affecting the rate of HD progression. 2009 Movement Disorder Society [source]

    Cortisol levels in umbilical vein and umbilical artery with or without antenatal corticosteroids

    Masahiro Manabe
    Abstract,Background:,The developmental changes of the umbilical cortisol levels in neonates at gestational age of 23,41 weeks were studied and the effect of antenatal steroid administration on the umbilical cortisol levels were examined. Methods:,Cortisol levels in the umbilical vein (UV) and the umbilical artery (UA) were studied in 35 neonates at the gestational age (GA) of 23,41 weeks with or without antenatal administration of corticosteroids. Serum cortisol concentrations were measured by the high performance liquid chromatography method. Results:,The correlation between cortisol levels in UV and birthweight (BW) was weak and negative in premature infants. UV cortisol levels in the neonates with antenatal corticosteroid were lower than those in the neonates without antenatal corticosteroid, but the relation was not significant. The developmental changes of UV cortisol levels were the same as those in Murphy's study (spontaneous-onset labor). The cortisol levels in UV and UA had a significantly positive correlation and both had almost equal concentrations. There were no correlations between cortisol levels in UV and placental weight, Apgar Score at 1 and 5 min. Conclusions:,In the neonates whose birthweight was less than 2000 g without antenatal corticosteroid, there was a negative correlation between cortisol levels in UV and BW but there was no correlation between cortisol levels in UV and GA. That the neonates with antenatal corticosteroid would have a suppressed adrenocortical function after birth could not be proved. [source]

    Positive predictive value of ICD-9 codes 410 and 411 in the identification of cases of acute coronary syndromes in the Saskatchewan Hospital automated database

    Cristina Varas-Lorenzo MD
    Abstract Background Case definitions are essential to epidemiological research. Objectives To evaluate ICD-9 codes 410 and 411 to identify cases of acute coronary syndromes (ACS), and the clinical information availability in the administrative and hospital discharge records of Saskatchewan, Canada. Methods In the context of a safety cohort study, we identified hospitalisations with primary discharge codes 410 (2260) and 411 (799). We selected all records with code 411, and a random sample (200) with code 410. Based on information obtained by trained abstractors from hospital records, events were classified by two cardiologists as definite or possible according to adapted AHA/ESC criteria. The validity of 410 and 411 codes was assessed by calculating the positive predictive value (PPV). Completeness of the recorded information on risk factors and use of aspirin was explored. Results The PPVs of the codes 410 and 411 for ACS were 0.96 (95%CI: 0. 92,0.98) and 0.86 (95%CI: 0.83,0.88), respectively. The PPV of 410 for acute myocardial infarction (AMI) was 0.95 (95%CI: 0.91,0.98). The PPV of 411 was 0.73 (95%CI: 0.70,0.77) for primary unstable angina (UA) and 0.09 (95%CI: 0.07,0.11) for AMI. Hospital charts review revealed key information for clinical variables, smoking, obesity and use of aspirin at admission. Conclusions ICD-9 410 code has high PPV for AMI cases, likewise 411 for UA cases. Case validation remains important in epidemiological studies with administrative health databases. Given the pathophysiology of ACS, both AMI and UA might be used as study end points. In addition to code 410, we recommend the use of 411 plus validation. Copyright 2008 John Wiley & Sons, Ltd. [source]