Vanillylmandelic Research Articles

Stabilization of urinary biogenic amines measured in clinical chemistry laboratories

Urinary 5-hydroxyindoleacetic acid (5-HIAA), vanillylmandelic (VMA), homovanillic acid (HVA), catecholamines and metanephrines are produced in excess by catecholamine-producing tumors. These biogenic amines are unstable at low or high pH and require hydrochloric acid (HCl) to prevent their degradation. However, HCl addition may result in very low pH causing degradation or deconjugation of several metabolites. This study evaluated the buffering properties of sodium citrate to stabilize all biogenic amines.The metabolite concentrations were measured by LC-MS/MS or by a coulometric assay in 22 urine samples collected native and with HCl or sodium citrate. We studied the effect of pH, time (48 h, four weeks) and storage temperature at 22 °C, 4 °C, and −20 °C.We found that catecholamines degradation was prevented by HCl and citrate and that 5-HIAA was degraded in 5 out of 22 samples collected with HCl. All biogenic amines were efficiently stabilized by citrate for four weeks at 22 °C, except epinephrine (48 h at 4 °C, or four weeks at −20 °C). Sodium citrate did not cause quantification or analytical artefacts concerns. In conclusion, sodium citrate is a non-hazardous alternative to HCl for patients to send unfrozen urine samples to the laboratory which may safely store the sample for four weeks.

Simultaneous Determination of Homovanillic and Vanillylmandelic Acid by HPLC Using a Coulometric Detector with Renewable Glassy Carbon Microbeads Based Working Electrode

AbstractHomovanilic (HVA) and vanillylmandelic (VMA) acid are catecholamines metabolites commonly used as cancer biomarkers. New method for simultaneous determination of both these metabolites is presented, using recently developed flow‐through coulometric detector based on glassy carbon microbeads. This application presents the potential opportunities of the above mentioned coulometric detector for the simultaneous determination of mixture of substances in complicated matrix in combination with gradient chromatography. Optimum conditions were set as follows: mobile phase consisting of acetonitrile (eluent A) and ten time diluted B‐R buffer pH 3 (eluent B) with gradient program 5 % A (2 min), 5 % A to 25 % A (8 min), 25 % A (4 min), 25 % A to 95 % A (1 min), and 95 % A (4 min); flow rate of mobile phase 0.7 mL min−1, detection potential +1.3 V, and injection volume 20 μL. Calibration dependences of both metabolites were linear from concentration 100 μmol L−1 to their quantitation limits (i.e. 0.6 μmol L−1 for HVA and 1.3 μmol L−1 for VMA, respectively). Standard addition method was applied for the determination of these analytes in human urine. Obtained results are in agreement with results of HPLC method with UV detector.

Effect of supine rest on cardiac autonomic tone in type 2 diabetes mellitus

Background: Autonomic nerve dysfunction has been noted in type 2 diabetes mellitus (T2DM). Regular practice of supine rest (SR) may cause improvement of this impaired autonomic nerve function.Objective: To observe the effect of SR on the autonomic nerve activity by analysis of heart rate variability (HRV) in patients with T2DM.Methods: This prospective interventional study was carried out in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU)during 2016 on 30 female diagnosed T2DM patients aged 50-55 years with duration of diabetes of 5-10 years. They performed SR (20 minutes twice daily) for 3 months. The diagnosed patients were selected from the Out Patient Department of Endocrinology, BSMMU, Dhaka. Thirty age matched apparently healthy females who did not perform regular SR, were control. To assess the cardiac autonomic nerve function, HRV parameters of all subjects were recorded by PowerLab. HRV data of all subjects were collected at baseline and also after 3 months follow-up. In addition, urinary level of Vanillyl Mandelic acid (VMA) of all subjects were measured at baseline and at post intervention period for patients. For statistical analysis, paired and independent sample t-tests were done, as applicable.Results: The pre-intervention values of LF normalized unit (LF nu), LF/HF ratio(p<0.01) and urinary VMA were significantly higher(p <0.001) and HF normalized unit (HF nu) was significantly (p<0.01)lower in all diabetic patients compared to control. The post-intervention data showed LF nu, LF/HF ratio and urinary VMA were reduced and HF nu was increased but these changes were not statistically significant (p> 0.05) in diabetic patients.Conclusion: This study concluded that parasympathetic activity decreased, increased sympathetic activity with higher sympathovagal balance indicating autonomic dysfunction in patients with T2DM, which was shown with trend of improvement after regular practice of supine rest of 3 months though statistically not significant.Bangladesh Soc Physiol. 2017, December; 12(2): 65-71

Novel Silica-Encapsulated Cu–Al Hydrotalcite Catalyst: Oxidative Decarboxylation of Vanillyl Mandelic Acid to Vanillin in Water at Atmospheric Pressure

Vanillin is a versatile chemical, having characteristics such as antimicrobial, antioxidant, anticarcinogenic, antimutagenic, hypolipidemic, and antisickling activities and is an intermediate for synthesis of fine chemicals such as vanilla flavoring. Vanilla is the second most expensive spice; it is extracted from vanilla beans and is in short supply. Therefore, to meet demand of vanilla flavor, the synthesis of vanillin via chemical routes is necessary. In this regard, a novel silica-encapsulated copper aluminum hydrotalcite (SECuAlHT) was synthesized. Different techniques such as XRD, FTIR, N2 adsorption–desorption, TGA-DSC, NH3 TPD, CO2 TPD, H2 chemisorption, TEM, and SEM-EDXS were used to characterize SECuAlHT. Its catalytic activity for oxidative decarboxylation of vanillyl mandelic acid (VMA) was investigated. Vanillin was obtained from VMA by oxidative decarboxylation using SECuAlHT in water as a solvent and atmospheric air under base-free conditions. The presence of basic sites in the catalyst was...

Green Synthesis of Vanillyl Mandelic Acid (Sodium Salt) from Guaiacol and Sodium Glyoxylate over Novel Silica Encapsulated Magnesium Hydroxide

Vanillyl mandelic acid (VMA) is an intermediate in the synthesis of vanillin and is an end-stage metabolite. In the present work, VMA (sodium salt) was selectively synthesized from guaiacol and sodium glyoxylate which can be sourced from biomass valorization. Different catalysts were prepared; out of which silica encapsulated magnesium hydroxide (SEMH) was active, selective, and reusable. Vanillyl mandelic acid (sodium salt) was efficiently obtained with 70% selectivity at guaiacol conversion of 55% over SEMH at 100 °C after 5 h. VMA could be obtained from the sodium salt. The Langmuir–Hinshelwood–Hougen–Watson (LHHW) model with weak adsorption of all species was found to describe the kinetics. The apparent activation energy for formation of vanillyl mandelic acid was 21.1 kcal mol–1.

Creating a system of medical and psychological rehabilitation of extreme professions representatives (firemen-rescuers as a model)

Chumaeva Julia , Golikov а Vladislava, Nekhoroshkova Julia , Ogulenko Alexey , Shafran Leonid. Creating a system of medical and psychological rehabilitation of extreme professions representatives (firemen-rescuers as a model). Journal of Education , Health and Sport . 2015;5(8):1 9 7 - 209 . ISSN 2391-8306 . DOI 10.5281/zenodo.28064 http://dx.doi.org/10.5281/zenodo.28064 http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%288%29%3A197-209 https://pbn.nauka.gov.pl/works/607738 Formerly Journal of Health Sciences. ISSN 1429-9623 / 2300-665X. Archives 2011–2014 http://journal.rsw.edu.pl/index.php/JHS/issue/archive Deklaracja. Specyfika i zawartośc merytoryczna czasopisma nie ulega zmianie. Zgodnie z informacją MNiSW z dnia 2 czerwca 2014 r., ze w roku 2014 nie bedzie przeprowadzana ocena czasopism naukowych; czasopismo o zmienionym tytule otrzymuje tyle samo punktow co na wykazie czasopism naukowych z dnia 31 grudnia 2014 r. The journal has had 5 points in Ministry of Science and Higher Education of Poland parametric evaluation. Part B item 1089. (31.12.2014). © The Author (s) 2015; This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland and Radom University in Radom, Poland Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. The authors declare that there is no conflict of interests regarding the publication of this paper. Received: 05.06.2015. Revised 15.07.2015. Accepted: 12.08.2015. CREATING A SYSTEM OF MEDICAL AND PSYCHOLOGICAL REHABILITATION OF EXTREME PROFESSIONS REPRESENTATIVES (FIREMEN-RESCUERS AS A MODEL) Julia Chumaeva 1 , Vladislava Golikovа 1,2 , Julia Nekhoroshkova 1 , Alexey Ogulenko 1 , Leonid Shafran 1 1 Ukrainian Scientific and Research Institute of Transport Medicine, Odessa, Ukraine 2 Odessa National Maritime Academy, Odessa, Ukraine Abstract Background. Working conditions of representatives of extreme professions (firemen-rescuers are a good example), are connected with disregulations and disorders of physiologic functions, fatigue accumulation and disadaptation. The medical and psychological rehabilitation is an effective way for occupational health and reliability restoration. However, last one is characterized by an empirical approach and conducted by priority of medical component, that significantly reduces effectiveness of the undertaken measures. So, it is necessary to develop a system of combined medical and psychological rehabilitation (MPR). Materials and methods. In this progect MPR was carried out in 238 specialists of three professional groups: firemen-rescuers (146), fire-engine drivers (44) and inspectors of fire safety (48 - control). Psychophysiological examination included the computerized program “MORTEST”, variant “SPAS-14” performance, answers to the individual-typological questionnaire (ITQ) and Eysenck personal test (EPT). The levels of epinephrine (Е), norepinephrine (NЕ), dopamine (DА) and dioxyphenylalanine (DOPA) urinal excretion, the vanillylmandelic (VMA) and homovanillic acids (HVA) levels in urine were also defined. The survey is conducted three times: at the beginning, middle and the end of a 12-day rehabilitation course. Statistical data processing was carried out by common programs in Microsoft Excel. Results and discussion. The studies have shown that the attributes to identify individual-typological differences are indicators of extroversion-introversion and anxiety in tests ITO and EPT. The results were divided into three clusters: extroverts with low anxiety (52.9%); ambiverts with low (27.7%) and high anxiety (19.4%). Simultaneously it was assigned different types of SAS response in the rehabilitation process: basic or balanced, epinephrinic, norepinephrinic, and with low secretory activity. Low efficiency of rehabilitation measures occurred in 40.7 ± 5,1% of surveyed firefighters with epinephrinic response type and SAS functional exhaustion. The type of SAS response allocated 3 levels of stress in fire-rescuers: adequate to professional load, with the signs of hormonal and mediatorial dissociation, and dangerous - with the depletion of all links of SAS. Conclusion. According to the results of the performed researches it was developed a system of MPR, which allows to conduct a differentiated remediation of firemen-rescuers in the view of occupational features, individually-typological properties of the rehabilitants’ personality, the nature and degree of changes in the central nervous, autonomic and hormonal systems. The developed approaches included in the elaborated Methodical Guidelines, implemented in practice. Key words: extreme professions, firemen-rescuers, medical and psychological rehabilitation, psychophysiological assessment, psychological markers, catecholamines excretion, effective measures elaboration.

Comparison of Diagnostic Accuracy of Urinary Free Metanephrines, Vanillyl Mandelic Acid, and Catecholamines and Plasma Catecholamines for Diagnosis of Pheochromocytoma

Recent evidence suggests that plasma-free metanephrines provide a highly sensitive test in patients requiring exclusion of pheochromocytoma. The diagnostic efficacy of urinary free metanephrines, however, has not been evaluated. OBJECTIVE, DESIGN, SETTING, PATIENTS, AND OUTCOME MEASURES: We compared retrospectively the diagnostic efficacy of 24-h urinary free metanephrines with our currently available measurements of 24-h urinary vanillyl mandelic acid (VMA), urinary catecholamines, and plasma catecholamines in 159 outpatients tested in a tertiary referral center for pheochromocytoma over a 4-yr period. The sensitivity of urinary free metanephrines was 100% [25 of 25 patients; 95% confidence interval (CI) 86-100%)] compared with the sensitivity of 84% (21 of 25; 95% CI 64-95%) for urinary catecholamines; 72% (18 of 25; 95% CI 51-88%) for urinary VMA; and 76% (16 of 21; 95% CI 53-92%) for plasma catecholamines. The specificity of urinary free metanephrines was 94% (116 of 123; 95% CI 89-98%), compared with the specificity of 99% (127 of 129; 95% CI 96-100%) for urinary catecholamines; 96% (130 of 134; 95% CI 91-98%) for urinary VMA; and 88% (66 of 75; 95% CI 78-94%) for plasma catecholamines. Receiver operating characteristic curves for all test groups were generated. Pairwise comparisons of the area under the receiver operating characteristic curve for urinary free metanephrines with that of each of the other three test groups individually were: 0.993 (95% CI 0.962-0.999) vs. 0.919 (95% CI 0.862-0.957, P = 0.032) for urine catecholamines; 0.993 (95% CI 0.962-0.999) vs. 0.846 (95% CI 0.778-0.900, P = 0.002) for urine VMA; and 0.992 (95% CI 0.945-0.998) vs. 0.852 (95% CI 0.762-0.918, P = 0.009) for plasma catecholamines. Testing with urinary free metanephrines failed to misidentify a single case of pheochromocytoma, compared with four missed cases for urinary catecholamines, seven missed cases for urinary VMA, and five missed cases for plasma catecholamines. Urinary free metanephrines were superior to urinary VMA, urinary catecholamines, and plasma catecholamines and can provide a valuable test for diagnosis of pheochromocytoma in adults.

MYCN oncogene amplification in neuroblastoma is associated with worse prognosis, except in stage 4s: the Italian experience with 295 children.

To evaluate the prognostic role of MYCN oncogene amplification in children with neuroblastoma. Of 694 children (age, 0 to 15 years) with previously untreated neuroblastoma, 295 (42%) were evaluated at diagnosis for MYCN gene amplification. Clinical characteristics and survival results of 295 patients studied and 399 not studied for MYCN were comparable. In 48 of 295 patients studied for MYCN (16%), the gene was amplified (> or = three gene copies). Amplification was more frequent in children older than 1 year, with abdominal tumor (18% v 7%), advanced disease, normal vanillylmandelic (VMA) urinary excretion, and high lactate dehydrogenase (LDH), ferritin, and neuron-specific enolase (NSE) serum levels. In patients studied for MYCN, the 5-year overall survival (OS) rate was higher for children aged less than 1 year (90% v 44%), with extraabdominal tumor, stage 1 or 2 versus 3 versus 4, and normal NSE, LDH, and ferritin serum levels. Patients with amplified MYCN had a worse OS (odds ratio [OR], 3.38; confidence interval [CI], 2.22 to 5.16). This association held after adjustment for other characteristics. The impact of MYCN amplification was greater in patients with favorable characteristics, in particular age (OR, 10.28 for infants; 2.08 for older children) and stage (OR, 35.3 for stage 1 to 2; 8.41 for stage 3; 1.76 for stage 4). However, of 29 children with stage 4s, all three with amplified MYCN survive. In a multivariate analysis, the prognostic role of MYCN amplification, age, and stage was confirmed, but the size of the effect of MYCN was dependent on age and stage. MYCN amplification is associated with a worse prognosis in children with neuroblastoma at all ages and stages except 4s. This association is most pronounced in children with otherwise favorable prognostic indicators, and in these children should be considered as an indication for more intensive intervention.

A 5-year (1990-1994) neuroblastoma screening feasibility study in France. Methodology and preliminary observations.

Following the pioneering Japanese experience, several European and North American groups implemented pilot studies on screening infants for neuroblastoma, considering the possibility of demonstrating a decrease in mortality rate. In France, a 5-year (1990-1994) feasibility study on neuroblastoma screening at the age of 4 months was initiated in the Rhône district (1.5 M inhabitants, 26,000 births per year). Vanillylmandelic (VMA) and homovanillic (HVA) acids were measured by HPLC, and creatinine (Cr) by the Jaffé's kinetic method on Technicon RA-XT. VMA and HVA were expressed as microgram/mg of Cr. The method was assessed with both a daily intra-laboratory control and a sample of urine obtained from a national quality control organism. The overall participation rate for the 5-year period was 82.2%. Out of 105,293 infants tested from 128,126 births, 12 NB cases were discovered with screening (screened cases) and 1 case was discovered with a late performed test (at 13 months of age). Six neuroblastomas were found clinically before the age of 4 m. Two cases were missed because the parents did not perform the test. Three children with normal tests at screening were false-negative cases: two of them were found secreting at diagnosis, while one remained non-secretory at diagnosis and later on. Otherwise, thirty-five false-positive tests were found. Biochemical observations are discussed. It is too early to reach clinical conclusions from this screening program on neuroblastomas as it is presently being followed up.

False positive results in a neuroblastoma screening programme.

Twenty thousand, eight hundred and twenty-nine babies were screened for neuroblastoma at 6 months of age by measuring homovanillic (HVA) and vanillylmandelic (VMA) acid in urine and rationing these to creatinine. Using a "cut off" of the mean + 3 SD, 10 were found to be positive. Two were found on evaluation to have neuroblastoma and in the remaining 8 the raised levels of HVA and/or VMA returned to normal. Only one of the 8 false positive babies was absolutely normal, most having a chronic disorder or illness. Utilising new centiles which relate HVA and VMA to creatinine, only 3 of the 8 would have remained positive, a false positive rate of 0.01%. The false negative rate would have remained unchanged.

Determination of urinary homovanillic and vanillylmandelic acids from dried filter paper samples: Assessment of potential methods for neuroblastoma screening

Urinary homovanillic (HVA) and vanillylmandelic (VMA) acids were analyzed on 200 random urine samples from patients with neuroblastoma and controls, after the samples had been dried onto absorbent filter paper. The acids were determined quantitatively by gas chromatography (GC) and qualitatively by thin layer chromatography (TLC). The results were analyzed for correlation between liquid urine samples and urine dried on filter paper and between TLC and GC methods. A high overall correlation for HVA and VMA (99%) was found between liquid and dried filter samples analyzed by GC. The correlations were more significant for samples with elevated levels of these acids than for those with normal levels. Normalization of the results to the urinary creatinine concentration (UCr) is indicated due to variations in urine concentration. Results from TLC analysis showed a false positive rate of 3.5% and a false negative rate of 0.5% compared to GC analysis. This work suggests that a combination of a sensitive TLC method with a rapid quantitative GC method would be suitable for mass neuroblastoma screening in infants.

Separation of vanillylmandelic (VMA) and homovanillic (HVA) acids from urine for assay by a two resin column system

A procedure is described for separating vanillylmandelic acid (VMA) and homovanillic acid (HVA) from urine so that they can be assayed by chemical means or gas chromatography. The process comprises passing a threefold diluted urine over cation exchange column (AG 50W-X12) to remove catecol amines and amino acids. The VMA and HVA is then adsorbed from the diluted urine to an anion exchange column (AG 2-X8). After washing with water, the HVA and VMA are eluted with an NaCl-K 2CO 3 solution. The VMA can be determined by oxidation to vanillin directly. By extraction with n-pentanone-2, after acidification and evaporation to dryness, the residue may be redissolved for processing or treated with a methylating reagent for gas chromatography. For the latter purpose, 4-methoxy benzophenone is recommended as the internal standard.

Enzymatic Method for Determination of Vanillyl Mandelic Acid

Abstract An enzymatic method is described for the measurement of vanillyl mandelic acid (VMA). The method utilizes an L-mandelic acid dehydrogenase preparation from Pseudomonas fluorescens A-312 to catalyze the transformation of VMA to vanillin. The method is specific for VMA because only the final product, vanillin, will absorb maximally at 350 mµ. The results compare favorably with the method of Pisano et al.(2).