OBJECTIVETo develop a method for determination of mandelic acid (MA) and phenylglyoxylic acid (PGA) in urine by reagent-free ion chromatography.

METHODSIon chromatography was performed on an AS19 column with a gradient elution solution containing 10-35 mmoL/L KOH at a flow rate of 1.00 ml/min, and MA and PGA were detected at ultraviolet wavelengths of 225 nm and 254 nm, respectively. The samples were diluted 10 times with purified water, then purified on a silver column to remove high concentrations of chloride ion, and injected after being filtered through a 0.2-µm m filter membrane.

RESULTSThe recoveries of standard addition of MA and PGA were 96.5% and 99.3%, respectively, with both relative standard deviations less than 5.0%. Good linear relationships were noted in the range of 1.0-100.0 mg/L for both MA and PGA (r >0.9995). The detection limits of MA and PGA were 0.02 mg/L and 0.05 mg/L, respectively; the minimum detectable concentrations of MA and PGA were 0.2 mg/L and 0.5 mg/L (when the sampling amount was 5.0 ml and diluted to 50.0 ml with water, and the injection volume was 300 µL).

CONCLUSIONSThis method is fast, convenient, and highly sensitive and selective. It can be used for the analysis of MA and PGA in the urine of styrene-exposed workers.

Chromatography, Ion Exchange ; Glyoxylates ; urine ; Humans ; Mandelic Acids ; urine ; Styrene

AIMTo establish a resolution method for alpha-cyclohexyl mandelic acid enantiomers by enantioselective extraction and to observe the effects of all kinds of tartaric esters, pH, the concentration of D-tartaric esters and beta-cyclodextrin on the enantioselectivity.

METHODSResolution of alpha-cyclohexyl mandelic acid enantiomers by enantioselective extraction with tartaric esters and beta-cyclodextrin has been studied.

RESULTSThe distribution behavior of alpha-cyclohexyl mandelic acid enantiomers in the separation system was studied. The effects of all kinds of tartaric esters, pH, the concentration of D-tartaric esters and beta-cyclodextrin on the enantioselectivity has been examined in the two-phase.

CONCLUSIONResults showed that the complex formed by D-iso-butyl-D-tartaric ester with R enantiomer is stabler than that with S enantiomer. With the increase of pH, the partition coefficient and separation factor decreased. The concentration of beta-cyclodextrin and D-tartaric ester had visible effect on the enantioselectivity.

Esters ; Mandelic Acids ; chemistry ; Stereoisomerism ; Tartrates ; chemistry ; beta-Cyclodextrins ; chemistry

OBJECTIVETo establish a GC/MS method for analysis of cotinine (COT), phenylglyoxylic acid (PA) and mandelic acid (MA) in human urine.

METHODSHuman urine samples were extracted by CCl(3) and derivatized with MSTFA after dried completely. The contents of COT, PA and MA were measured by GC/MS method with DB-5MS capillary column and EI ion-source.

RESULTThe calibration curves for COT in urine samples were linear over the concentration ranges of 0.0002 approximately 3.5 microg ml(-1), while PA and MA were both of 1.25 approximately 160 microg ml(-1). The limits of quantification were 0.0002 microg ml(-1), 1.25 microg ml(-1) and 1.25 microg ml(-1) for COT, PA and MA, respectively. The assay recoveries for COT, PA and MA ranged from 89.53% approximately 102.4%, 84.88% approximately 91.46% and 83.46% approximately 13.6%, respectively.

CONCLUSIONThe established method can detect cotinine, phenylglyoxylic acid and mandelic acid simultaneously, which would be used in routine assessment and monitoring of the internal exposure to nicotine and styrene in human body.

Cotinine ; urine ; Environmental Pollutants ; urine ; Gas Chromatography-Mass Spectrometry ; Glyoxylates ; urine ; Humans ; Mandelic Acids ; urine

Urinary excretion of vanillymandelic acid (VMA) during a period of 24 hours was determined in 127 normal Korean adults and in 27 patients suffering from primary hypertension. The diurnal and nocturnal variations of urinary VMA excretion were measured in 3O normal persons and 11 patients with primary hypertension, and the day to day variations of urinary VMA excretion in l2 normal persons. The mean daily output of urinary VMA was fairly constant in each individual but varied widely between individuals. The mean daily output of urinary VMA in normal Korean adults is 1.95 +/- 1.15 (S.D.)mg, which is similar to that observed in occidentals. There is no significant difference between the nocturnal and the diurnal excretion of VMA. The mean daily output of urinary VMA in patients with primary hypertension was 2.17 +/- 0.76(S.D.) mg. This means that there is no significant variation in the urinary excretion of VMA between normal adults and patients with primary hypertension. Furthermore, the urinary output of VMA is not influenced by the sex.
Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; Female ; Human ; Hypertension/*metabolism ; Korea ; Male ; Mandelic Acids/*urine ; Middle Aged

OBJECTIVETo explore the adduct characteristics of styrene and DNA.

METHODSThe adduct reactions between styrene, urinary mandalic acid(MA), phenylglyoxalic acid(PGA), mercapturic acid of styrene (UMA) and DNA were studied by ultraviolet spectral analysis. The SO-DNA adducts by 32P-post labeled method, the chemical structures of SO-DNA adducts by GC-MS and NMR were also studied.

RESULTSSO combined with DNA at O6, N2 positions of dGMP to form six adducts, but styrene, urinary mandalic acid, phenylglyoxalic acid and mercapturic acid of styrene did not react with DNA to form adduct.

CONCLUSIONSStyrene formed adduct with DNA through its active center metabolite--SO after entering the body. SO combined with DNA at O6, N2 positions of dGMP to form adducts. If these DNA adducts are not repaired or are mis-repaired before cell duplication, the gene mutation and chemical damage would happen. No adduct reactions are seen among other metabolites of styrene.

Acetylcysteine ; metabolism ; DNA ; metabolism ; DNA Adducts ; metabolism ; DNA Repair ; Glyoxylates ; metabolism ; Humans ; Mandelic Acids ; metabolism ; Styrene ; metabolism

PURPOSE: Central nervous system (CNS) and cardiovascular system (CVS) side effects of anticholinergic agents used to treat overactive bladder (OAB) are underreported. Hence, this review aimed to focus on the mechanisms of CNS and CVS side effects of anticholinergic drugs used in OAB treatment, which may help urologists in planning the rationale for OAB treatment. MATERIALS AND METHODS: PubMed/MEDLINE was searched for the key words "OAB," "anticholinergics," "muscarinic receptor selectivity," "blood-brain barrier," "CNS," and "CVS side effects." Additional relevant literature was determined by examining the reference lists of articles identified through the search. RESULTS: CNS and CVS side effects, pharmacodynamic and pharmacokinetic properties, the metabolism of these drugs, and the clinical implications for their use in OAB are presented and discussed in this review. CONCLUSIONS: Trospium, 5-hydroxymethyl tolterodine, darifenacin, and solifenacin seem to have favorable pharmacodynamic and pharmacokinetic properties with regard to CNS side effects, whereas the pharmacodynamic features of darifenacin, solifenacin, and oxybutynin appear to have an advantage over the other anticholinergic agents (tolterodine, fesoterodine, propiverine, and trospium) with regard to CVS side effects. To determine the real-life situation, head-to-head studies focusing especially on CNS and CVS side effects of OAB anticholinergic agents are urgently needed.
Benzhydryl Compounds ; Benzilates ; Benzofurans ; Cardiovascular System* ; Central Nervous System* ; Cholinergic Antagonists* ; Cresols ; Mandelic Acids ; Metabolism ; Pyrrolidines ; Quinuclidines ; Receptors, Muscarinic ; Tetrahydroisoquinolines ; Urinary Bladder, Overactive* ; Solifenacin Succinate

OBJECTIVETo investigate the role of genetic polymorphisms of epoxide hydrolase 1 (EPHX1) in the metabolism of styrene in vivo.

METHODSFifty-six styrene-exposed workers, who worked in the painting workshop of an enterprise for manufacturing glass fiber-reinforced plastic yachts in Shandong Province, China for over one year and were protected in approximately the same way, were selected as study subjects. The 8-hour time-weighted average concentration (8 h-TWA) of styrene and the concentrations of mandelic acid (MA) and phenyl glyoxylic acid (PGA) as urinary metabolites were measured. The genetic polymorphisms of EPHX1 were detected by polymerase chain reaction-restriction fragment length polymorphism analysis.

RESULTSThe urinary concentrations of MA and PGA were 177.25±82.36 mg/g Cr and 145.91±69.73 mg/g Cr, respectively, and the 8 h-TWA of styrene was 133.28±95.81 mg/m3. Urinary concentrations of MA and PGA were positively correlated with 8 h-TWA of styrene (R=0.861, P < 0.05; R=0.868, P < 0.05). The subjects were divided into high-exposure group (8 h-TWA >50 mg/m(3)) and low-exposure group (8 h-TWA ≤ 50 mg/m(3), and in the two groups, the urinary concentrations of MA and PGA were significantly higher in the individuals carrying high-activity genotypes of EPHX1 than in those carrying low-activity genotypes of EPHX1 (P < 0.05).

CONCLUSIONGenetic polymorphisms of EPHX1 play an important role in the metabolic process of styrene in vivo.

Adult ; Air Pollutants, Occupational ; pharmacokinetics ; China ; Epoxide Hydrolases ; genetics ; Glyoxylates ; urine ; Humans ; Male ; Mandelic Acids ; urine ; Occupational Exposure ; Polymorphism, Genetic ; Styrene ; pharmacokinetics

OBJECTIVETo study the biomarkers of styrene and to provide theoretical basis for bio-monitoring of styrene.

METHODSUrinary mandalic acid (MA), phenylglyoxalic acid (PGA) and mercapturic acid (MUA) of styrene were examined by high performance liquid chromatography (HPLC).

RESULTSThe correlation regression equations between exposure dose and MA, PGA and MUA level in morning urinary samples were: ŷ = 2.58x + 70.82; ŷ = 1.66x + 37.42; ŷ = 0.05x + 0.55 respectively. The correlation regression equations between exposure dose and MA, PGA and MUA level in post-shift urinary samples were: ŷ = 1.85x + 89.02; ŷ = 1.33x + 4.32; ŷ = 0.04x + 0.68 respectively. All showed close dose-response relationship.

CONCLUSIONSThe level of MA, PGA and MUA in morning or post-shift urinary samples may be used as bio-monitoring indexes of styrene.

Acetylcysteine ; urine ; Adult ; Biomarkers ; Chromatography, High Pressure Liquid ; Environmental Monitoring ; Glyoxylates ; urine ; Humans ; Male ; Mandelic Acids ; urine ; Regression Analysis ; Styrene ; metabolism

OBJECTIVES: In this study, we summarized the External Quality Assessment Scheme (EQAS) for the biological monitoring of occupational exposure to toxic chemicals which started in 1995 and continued until a 31st round robin in the spring of 2010. The program was performed twice per year until 2009, and this was changed to once a year since 2010. The objective of the program is to ensure the reliability of the data related to biological monitoring from analytical laboratories. METHODS: One hundred and eighteen laboratories participated in the 31st round robin. The program offers 5 items for inorganic analysis: lead in blood, cadmium in blood, manganese in blood, cadmium in urine, and mercury in urine. It also offers 10 items for organic analysis, including hippuric acid, methylhippuric acid, mandelic acid, phenylglyoxylic acid, N-methylformamide, N-methylacetamide, trichloroacetic acid, total trichloro-compounds, trans,trans-muconic acid, and 2,5-hexanedione in urine. Target values were determined by statistical analysis using consensus values. All the data, such as chromatograms and calibration curves, were reviewed by the committee. RESULTS: The proficiency rate was below 70% prior to the first round robin and improved to over 90% for common items, such as PbB and HA, while those for other items still remained in the range of 60-90% and need to be improved up to 90%. CONCLUSION: The EQAS has taken a primary role in improving the reliability of analytical data. A total quality assurance scheme is suggested, including the validation of technical documentation for the whole analytical procedure.
Acetamides ; Cadmium ; Calibration ; Consensus ; Dietary Sucrose ; Environmental Monitoring ; Formamides ; Glyoxylates ; Hexanones ; Hippurates ; Mandelic Acids ; Manganese ; Occupational Exposure ; Songbirds ; Sorbic Acid ; Trichloroacetic Acid

PURPOSE: Adenosine triphosphate (ATP) from the urothelium acts as a sensory neurotransmitter and is augmented in many diseases, such as overactive bladder. We investigated the effects of intravesical instillation of oxybutynin on ATP-induced bladder overactivity to determine whether this effect is mediated by effects on urothelial muscarinic receptors. MATERIALS AND METHODS: Cystometry (at rate of 0.04 ml/min) was performed in female Sprague-Dawley rats (body weight 250 g) under urethane anesthesia (1.2 g/kg). After a 2-hour baseline period, protamine sulfate (10 mg/ml) was instilled for 1 hour, and then ATP (60 mM, pH 6.0) or a mixture of oxybutynin (10(-6) M) and ATP (60 mM, pH 6.0) was instilled intravesically. We performed experiments with 4-diphenylacetoxy-N-methylpiperidine methobromide (4-DAMP) and methoctramine by the same methods. Cystometric parameters, such as the intercontraction interval (ICI), pressure threshold (PT), and maximal voiding pressure (MVP), were compared. RESULTS: With intravesical instillation of ATP after protamine sulfate treatment, the ICI was decreased compared with baseline (ICI: baseline, 487.1+/-64.8 s; protamine, 450.6+/-56.1 s; ATP, 229.7+/-35.3 s; p<0.05). Addition of oxybutynin, 4-DAMP, or methoctramine in the ATP solution did not significantly change the ICI compared with ATP solution alone (ICI: oxybutynin, 189.1+/-32.3 s; 4-DAMP, 161.1+/-22.8 s; methoctramine, 341.0+/-113.3 s; p>0.05). Intravesical instillation of ATP decreased MVP and PT significantly compared with baseline, but MVP and PT were not changed significantly with oxybutynin, 4-DAMP, or methoctramine compared with ATP. CONCLUSIONS: Bladder overactivity induced by intravesical instillation of ATP was not suppressed by intravesical instillation of antimuscarinics. Suppression of ATP-induced bladder overactivity by intravenous oxybutynin is not mediated by urothelial muscarinic receptors.
Adenosine ; Adenosine Triphosphate ; Administration, Intravesical ; Anesthesia ; Animals ; Diamines ; Female ; Humans ; Hydrogen-Ion Concentration ; Mandelic Acids ; Muscarinic Antagonists ; Neurotransmitter Agents ; Piperidines ; Polyphosphates ; Protamines ; Rats ; Rats, Sprague-Dawley ; Receptors, Muscarinic ; Urethane ; Urinary Bladder ; Urinary Bladder, Overactive ; Urothelium