Oxide In Urine Research Articles

Determination of Cotinine, 3'-Hydroxycotinine and Nicotine 1'-Oxide in Urine of Passive and Active Young Smokers by LC-Orbitrap-MS/MS Technique.

Tobacco smoke is probably the most significant factor conducing to toxic xenobiotics exposure to humans. The aim of the study was to develop a rapid and sensitive method for the determination of selected nicotine metabolites in urine of tobacco smokers and passive smokers. The method for removing protein and extracting the metabolites involved the centrifugation of urine with acetonitrile. Cotinine, trans-3'-hydroxycotinine, and (2'S)-nicotine 1'-oxide in the supernatant were determined using the LC-Orbitrap-MS/MS technique, with the selected ion monitoring (SIM) and parallel reaction monitoring (PRM) modes used. The recovery of these analytes added to the urine samples ranged from 72% to 101%. Repeatability and reproducibility were less than 3.1% and 10.1%, respectively. The study was carried out among medical students. The group was selected as representatives of young people and who as future physicians should be more aware of the effects of nicotine use. Concentration levels of cotinine and trans-3'-hydroxycotinine determined in ng/mL in the urine of cigarette smokers were 70- and 58-fold higher, respectively, compared to passive smokers. Higher concentrations were recorded in the urine of those passively exposed to tobacco smoke than in non-smokers, confirming that passive exposure to tobacco smoke is not harmless to the human body. However, no significant differences were observed in the concentration of (1'S,2'S)-nicotine 1'-oxide in the samples of individuals from various groups.

THE PROTECTIVE EFFECT OF L- ARGININE AND ASCORBIC ACID ON DEXAMETHASONE INDUCED-HYPERTENSION IN RATS

Excess use of glucocorticoids either natural or synthetic has been associated with hypertension. Dexamethasone is a synthetic glucocorticoid with multiple uses. Recent studies demonstrated that dexamethasone induced hypertension is of endothelial dysfunction and decreased nitric oxide (NO) production. This work was designed to investigate the protective effect of L-arginine and ascorbic acid on dexamethasone induced hypertension in rats. Thirty adult male Albino rats were used in this study. Rats were equally divided into 5 groups: (G 1) Negative control group, (G 2): Positive hypertensive group, (G 3): L – arginine treated group, (G 4): Ascorbic acid treated group and (G 5): combined L-arginine and ascorbic acid treated group. L – arginine, ascorbic acid were given 2 weeks before induction of hypertension. Rats were followed up by measuring arterial blood pressure, Nitric oxide in urine and tissue homogenate, Total antioxidant capacity in serum and histopathology. Dexamethasone increased systolic (260.16 ± 28.9 mmHg) and diastolic blood pressure (149.8 ± 7.22 mmHg), decaresed NO in tissue (72.1 ± 5.2 μmol/ g (and urine (0.26 ± 0.04 μmol/ 24h(. Combination between L-arginine and ascorbic acid normalized systolic (118.6 ± 5.3 mmHg) and diastolic (79.5 ± 5.04 mmHg ) blood pressure and increased NO in aortic tissue (135.5 ±7.1μmol/ g) and urine (0.6 ± 0.08 μmol/ 24h) denoting that combination between L-arginine and ascorbic acid could effectively prevent dexamethasone induced hypertension

RISK FACTORS AND MARKERS OF TUBULOINTERSTITIAL NEPHRITIS DEVELOPMENT IN CHILDREN WITH OXALATE-CALCIUM CRYSTALLURIA

Research objective: to study the clinical and biochemical risk factors and markers for the formation of tubulointerstitial nephritis in children with oxalate-calcium crystalluria. Methods: 30 children with tubulointerstitial nephritis were examined on a background of oxalate-calcium crystalluria. Special clinical and laboratory methods of research were used: stable metabolites of nitric oxide-nitrites and activity of superoxide dismutase, albumin in urine were determined in erythrocytes and urine. To determine the clinical features of the course and identify risk factors for the development of tubulointerstitial nephritis, we analyzed: perinatal and genealogical anamnesis, the age of debut of oxalate-calcium crystalluria and tubulointerstitial nephritis, and ultrasound data from the organs of the urinary system. Results: In children with tubulointerstitial nephritis, in 22% of cases the signs of oxalate-calcium crystal-luria preceded the underlying disease. For tubulointerstitial nephritis, which occurred against the background of metabolic disturbances, whose debut occurred at an early age, a latent course is typical, and minimal tubular kidney dysfunction, formed at the age of 4–11 years. The following clinical and anamnestic factors had the greatest impact on the formation of tubulointerstitial nephritis from a single-factor analysis: a family history with family history and the presence of 2 degrees of kinship of urolithiasis, a threat of termination of pregnancy and gestosis of the first half of pregnancy, hyperechoic inclusions in the renal parenchyma by ultrasound examination of child. In parallel with the processes of antioxidant protection against the background of oxidative stress, there is an increase in the level of metabolites of nitric oxide in the urine, and in combination with albuminuria, an increase in endothelial dysfunction. Conclusion: the leading factors in the formation of tubulointerstitial nephritis in children with oxalate-calcium crystalluria are an aggravated genealogical anamnesis due to the presence of urolithiasis in relatives of the first and second degree of kinship. According to the results of special research methods, albuminuria, low activity of superoxide dismutase in the urine, higher levels of nitric oxide in erythrocytes and urine indicate the progression of tubulointerstitial nephritis and are markers of the inflammatory process.

Separation and determination of 241Am in urine samples from radiation workers using PC88-A and alpha spectrometry

Bioassay technique is used for the estimation of actinides present in the body based on their excretion rate through body fluids. For occupational radiation workers urine assay is the preferred method for monitoring of chronic internal exposure. Determination of low concentrations of actinides such as plutonium, americium and uranium at low level of mBq in urine by alpha spectrometry requires pre-concentration of large volumes of urine. This article deals with standardization of analytical method for the determination of 241Am isotope in urine samples using Extraction Chromatography (EC) and 243Am tracer for radiochemical recovery. The method involves oxidation of urine followed by co-precipitation of americium along with calcium phosphate. This precipitate after treatment is further subjected to calcium oxalate co-precipitation. Separation of Am was carried out by EC column prepared by PC88-A (2-ethyl hexyl phosphonic acid 2-ethyl hexyl monoester) adsorbed on microporous resin XAD-7 (PC88A-XAD7). Am-fraction was electro-deposited and activity estimated using tracer recovery by alpha spectrometer. Ten routine urine samples of radiation workers were analyzed and consistent radiochemical recovery was obtained in the range 44–60% with a mean and standard deviation of 51 and 4.7% respectively.

The analysis of nicotine-1‘-N-oxide in urine, in the presence of nicotine and cotinine, and its application to the study of in vivo nicotine metabolism in man

Abstract A rapid quantitative assay for nicotine-1′-N-oxide in urine, in the presence of nicotine and cotinine, is reported. The urinary excretion of nicotine, cotinine and nicotine-1′-N-oxide was determined after nicotine had been administered in cigarette smoke, orally, or intravenously to subjects with either fluctuating, controlled acidic or controlled alkaline urinary pH. The urinary excretion of the N-oxide in 24 h from smokers under normal conditions was about half that of the cotinine excretion; more trans- than cis-diastereoisomer of nicotine-1′-N-oxide was excreted.

A flow injection electrospray ionization tandem mass spectrometric method for the simultaneous measurement of trimethylamine and trimethylamine N‐oxide in urine

Key metabolites for the diagnosis of the genetic disorder trimethylaminuria are trimethylamine (TMA) and trimethylamine N-oxide (TMAO). A rapid, automatable flow injection ESI-MS/MS method for their measurement in urine has been developed. The TMA was derivatized with ethyl bromoacetate to form ethyl betaine bromide. The 2 min ESI-MS/MS analysis employed four multiple reaction monitoring (MRM) ion pairs for derivatized TMA (146.1, 118.1), derivatized (2)H(9)-TMA (155.1, 127.1), TMAO (76.1, 58.1) and (2)H(9)-TMAO (85.1, 66.1). In control urine samples (n = 27) referred for suspected metabolic problems TMA was 0.11-1.19 mmol/mol creatinine, TMAO was 13.5-181 mmol/mol creatinine and the TMA/TMAO ratio was 0.0025-0.055. In five patients with diagnosed trimethylaminuria, TMA was 5.3-230 mmol/mol creatinine, TMAO was 0.36-607 mmol/mol creatinine and the TMA/TMAO ratio was 0.20-134.

Changes in End Products of Nitric Oxide in Urine and Induction of Nitric Oxide Synthase Expression in Urinary Bladder During Intravesical Instillations of IFN-α2b

Interferon-alpha2b (IFN-alpha2b) is being used intravesically for preventing recurrence and progression of superficial transitional cell carcinoma of the bladder. However, its mechanism of action when instilled intravesically is not yet elucidated. We monitored end products of nitric oxide (NO) in urine in 12 bladder cancer patients undergoing intravesical instillations of IFN-alpha2b. Urine end products of NO levels rose gradually after each instillation, reaching a peak value after the third instillation. Although the patients continued their treatment for 5 more weeks, no further alteration was observed. Inducible nitric oxide synthase (iNOS) expression was immunohistochemically evaluated in urinary bladder biopsy specimens before and after IFN-alpha2b instillations. It was shown that IFN-alpha2b induced urothelial iNOS expression, with subsequent oxidative stress. The peroxynitrite (ONOO-) formed from the combination of NO with superoxide (O2-) provides important clues in the role of ONOO- as a causative factor in the antineoplastic action of IFN-alpha2b.

Changes in End Products of Nitric Oxide in Urine and Induction of Nitric Oxide Synthase Expression in Urinary Bladder During Intravesical Instillations of IFN-α2b

Interferon-α2b (IFN-α2b) is being used intravesically for preventing recurrence and progression of superficial transitional cell carcinoma of the bladder. However, its mechanism of action when instilled intravesically is not yet elucidated. We monitored end products of nitric oxide (NO) in urine in 12 bladder cancer patients undergoing intravesical instillations of IFN-a2b. Urine end products of NO levels rose gradually after each instillation, reaching a peak value after the third instillation. Although the patients continued their treatment for 5 more weeks, no further alteration was observed. Inducible nitric oxide synthase (iNOS) expression was immunohistochemically evaluated in urinary bladder biopsy specimens before and after IFN-α2b instillations. It was shown that IFN-α2b induced urothelial iNOS expression, with subsequent oxidative stress. The peroxynitrite (ONOO–) formed from the combination of NO with superoxide (O2–) provides important clues in the role of ONOO– as a causative factor in the antineoplastic action of IFN-a2b.

High-performance Liquid Chromatographic Measurement of NicotinamideN-Oxide in Urine after Extracting with Chloroform

High-performance Liquid Chromatographic Measurement of Nicotinamide<i>N</i>-Oxide in Urine after Extracting with Chloroform

Stability and inactivation of mutagenic drugs and their metabolites in the urine of patients administered antineoplastic therapy

Urine samples from patients administered mutagenic antineoplastic drugs are mutagenic in the Ames assay, and hence may pose a genotoxic hazard to hospital personnel or family members caring for the patient. The urine samples in the present study were tested for mutagenicity in several strains of Salmonella typhimurium that were uvr negative (TA98, TA100) or positive (TA102, UTH8413, UTH8414), and were analyzed for the presence of drugs and their metabolites using high-pressure liquid chromatography (HPLC). Urine samples from cancer patients were kept at room temperature and their mutagenicity as well as the chemical stability of the drugs was tested for a period of 14 days. It was observed that, in general, the urine remained mutagenic for the 14-day period while the parent compound degraded within the first seven days. An exception was cisplatin, which was chemically stable as platinum, but the urine decreased in mutagenicity with time. This decrease was probably the result of ligand exchange with the platinum. Inactivation methods were developed to reduce the genotoxic hazard posed by the mutagenic compounds in the urine. Cisplatin was inactivated by complexing with sodium diethyldithiocarbamate (DDTC). Oxidation of urine containing mitomycin C and doxorubicin (sodium thiosulfate must be added to urine containing doxorubicin) with 5.25% sodium hypochlorite solution (bleach) results in mutagenic inactivation. Urine containing cyclophosphamide and its metabolites was oxidized with alkaline potassium permaganate and the active degradation products trapped with sodium thiosulfate. Both chemical and mutagenic assays are necessary to determine the reduction of risk. Methods of inactivation of mutagenic urine developed in this study are both effective and practical for the reduction of exposure to genotoxic hazards.

The gas-liquid chromatography of steroid formates; an application in congenital adrenal hyperplasia.

SUMMARY The gas-liquid chromatography (GLC) of some C19 steroid formates has been investigated in an attempt to speed up the final stages of the estimation of the 11-oxygenation index. SE-30 was found to give the best separation of the urinary C19 steroids formed after borohydride reduction and periodate oxidation of urine. Formates, acetates, propionates, n-butyrates, valerates and trimethylsilyl ethers were examined; formate esters gave the best separation of androsterone and aetiocholanolone. Estimation of the 11-oxygenation index by GLC increases the specificity and speed of single estimations and it is suggested that this method may find use as a rapid screening test for abnormal urinary steroid patterns.

The determination of mercury in urine; single extraction method.

Abstract Mercury is determined by the mixed color method using dithizone; interfering elements are eliminated by complexing with versene and by pH control. The published ashing techniques have been studied in conjunction with the single extraction method. Careful oxidation of urine with potassium permanganate and sulfuric acid is recommended. The sensitivity of the method is 1 μg. of mercury with an accuracy of 94.2 ± 4.82%. The advantage of this procedure is the speed of analysis, and purification of the reagents is unnecessary.