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  1. Br J Addict, 1992 Sep;87(9):1356.
    PMID: 1392558
    Matched MeSH terms: Substance Abuse Detection/legislation & jurisprudence*
  2. Aasim WR, Gan SH, Tan SC
    Biomed Chromatogr, 2008 Sep;22(9):1035-42.
    PMID: 18655218 DOI: 10.1002/bmc.1073
    A stereospecific gas chromatography-mass spectrometry analysis method for amphetamine-type stimulants in human urine was recently developed. For maximum efficiency, liquid-liquid extraction and chiral derivatization of the analytes using (R)-(-)-alpha-methoxy-alpha-(trifluoromethyl)phenylacetyl chloride were performed simultaneously. The effects of (1) use of saturated sodium chloride in 2.0 M sodium hydroxide, (2) extraction solvent volume, (3) percentage of triethylamine, (4) derivatization reagent volume, (5) sample mixing time, (6) incubation temperature and (7) incubation time on method sensitivity and variability were assessed using a two-level, eight-run Plackett-Burman design followed by a fold-over design. The use of saturated sodium chloride solution and the derivatization reagent volume were significant factors (ANOVA, p<0.01). The saturated sodium chloride solution decreased sensitivity whereas an increased volume of derivatization reagent increased sensitivity. Calibration curves for all analytes were linear between 5 and 500 microg/L, with correlation coefficients of >0.99. Detection limits were
    Matched MeSH terms: Substance Abuse Detection/methods*
  3. Chan KB, Pakiam C, Rahim RA
    Bull Narc, 2005;57(1-2):249-56.
    PMID: 21338025
    Recently, the abuse of ketum, an indigenous psychoactive plant, has received a lot of attention in Malaysia. To help national law enforcement agencies control its abuse, the laboratory of the Forensic Division has developed a procedure for its positive identification. Botanical identification may not be practical or conclusive, owing to the wide range of ketum materials available on the market, including dry macerated leaves, powdered leaves and drinks. In order to confirm that a substance is, in fact, ketum or that a preparation is derived from ketum, gas chromatography-mass spectrometry is used to definitively identify the presence of the psychoactive principle mnitragynine.
    Matched MeSH terms: Substance Abuse Detection/legislation & jurisprudence*
  4. Singh GK, Jimenez M, Newman R, Handelsman DJ
    Drug Test Anal, 2014 Apr;6(4):336-41.
    PMID: 23606665 DOI: 10.1002/dta.1481
    Urine provides a convenient non-invasive alternative to blood sampling for measurement of certain hormones. Urinary luteinizing hormone (LH) measurements have been used for endocrinology research and anti-doping testing. However, the commercially available LH immunoassays are developed and validated for human blood samples but not urine so that LH assays intended for use with urine samples need thorough validation. Therefore, the present study evaluated the measurement of urinary LH immunoreactivity using previously validated immunofluorometric (IF) and immunochemiluminometric (ICL) LH assays after prolonged frozen storage. LH was measured in serial urine samples following administration of a single injection of one of two doses of recombinant human chorionic hormone (rhCG) with assays run at the end of study (2008) and again after four years of frozen (-20 °C) storage where samples were stored without adding preservatives. The ICL assay showed quantitatively reproducible LH measurements after prolonged -20 °C storage. However, the IF immunoassay gave consistently lower LH levels relative to ICL (2008) with a further proportionate reduction after four years of sample storage (2012). Yet, both the assays displayed similar patterns of the time-course of urine LH measurement both before and after four years of frozen storage. In conclusion, we found that both immunoassays are suitable for urinary LH measurements with ICL assay being more robust for quantitative urinary LH measurement such as for anti-doping purposes, whereas the IF could be applicable for research studies where urine LH levels are compared within-study but not in absolute terms.
    Matched MeSH terms: Substance Abuse Detection
  5. Philipp AA, Wissenbach DK, Weber AA, Zapp J, Maurer HH
    Anal Bioanal Chem, 2011 Mar;399(8):2747-53.
    PMID: 21249338 DOI: 10.1007/s00216-011-4660-9
    Mitragyna speciosa (Kratom) is currently used as a drug of abuse. When monitoring its abuse in urine, several alkaloids and their metabolites must be considered. In former studies, mitragynine (MG), its diastereomer speciogynine (SG), and paynantheine and their metabolites could be identified in rat and human urine using LC-MS(n). In Kratom users' urines, besides MG and SG, further isomeric compounds were detected. To elucidate whether the MG and SG diastereomer speciociliatine (SC) and its metabolites represent further compounds, the phase I and II metabolites of SC were identified first in rat urine after the administration of the pure alkaloid. Then, the identified rat metabolites were screened for in the urine of Kratom users using the above-mentioned LC-MS(n) procedure. Considering the mass spectra and retention times, it could be confirmed that SC and its metabolites are so far the unidentified isomers in human urine. In conclusion, SC and its metabolites can be used as further markers for Kratom use, especially by consumption of raw material or products that contain a high amount of fruits of the Malaysian plant M. speciosa.
    Matched MeSH terms: Substance Abuse Detection/methods*
  6. Lua PL, Talib NS
    Altern Ther Health Med, 2013;19(4):28-42.
    PMID: 23981370
    Substance abuse has been prevalent in Malaysia for many years and currently represents one of the main concerns to its society. The limitations of conventional therapies have resulted in efforts to explore the potentia of complementary therapies in the management of drug addiction. The evidence for auricular acupuncture (AA) as a potential complementary therapy for drug addiction is still limited and inconclusive.
    Matched MeSH terms: Substance Abuse Detection/methods
  7. Mountjoy M, Akef N, Budgett R, Greinig S, Li G, Manikavasagam J, et al.
    Br J Sports Med, 2015 Jul;49(13):887-92.
    PMID: 25833900 DOI: 10.1136/bjsports-2014-094424
    Antidoping and medical care delivery programmes are required at all large international multisport events.
    Matched MeSH terms: Substance Abuse Detection/methods*
  8. Siddiqui MJ, Aslam A, Khan T
    J Pharm Bioallied Sci, 2019 3 25;11(1):43-48.
    PMID: 30906139 DOI: 10.4103/jpbs.JPBS_174_18
    Objective: The aim and objective of this study was to find the immunostimulant and immunomodulatory effect of T. ammi seed extracts.

    Methods: Seeds of T. ammi were extracted using three different solvents n-hexane, chloroform, and methanol by using soxhlet apparatus. To assess the immunomodulatory effect, delayed-type hypersensitivity (DTH) assay method was used and by the DTH assay, the effect of T. ammi on the skin thickness of rats was estimated. To find the exact dose for administration, acute toxicity test was performed using crude methanolic extract at a dose of 400, 800, 1600, and 3200mg/kg. After acute toxicity test, 500mg/kg dose was determined as safe for therapeutic effect and immunomodulatory effect was evaluated at this dose. Dose of 500mg/kg was administered to Wistar rats daily for 14 days and skin thickness of rats was measured at 24, 48, and 72h.

    Results: Results were obtained from six groups of rats, which were positive control group, negative control group, and the groups receiving the test drugs. Standard drug was the combination of sodium selenite, vitamin E, and sodium chloride and it showed more positive results as compared to that of test drug. Furthermore, among the three extracts, methanol extract showed more effectiveness on skin thickness.

    Conclusion: There was a meaningful difference was observed between the skin thickness of rats which shows that T. ammi have good immunomodulatory as well as immunostimulant activity.

    Matched MeSH terms: Substance Abuse Detection
  9. Diong SH, Mohd Yusoff NS, Sim MS, Raja Aziddin RE, Chik Z, Rajan P, et al.
    J Anal Toxicol, 2014 Nov-Dec;38(9):660-6.
    PMID: 25106416 DOI: 10.1093/jat/bku096
    Gas chromatography-mass spectrometry quantitative method was developed to monitor concentrations of methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in plasma and urine of patients. The developed method was simple, accurate and reproducible to quantify methadone and EDDP in plasma and urine samples in the concentration range of 15-1,000 and 50-2,000 ng/mL, respectively. The proposed analytical method was applied to plasma and urine samples obtained from 96 patients undergoing methadone maintenance treatment (MMT) with daily methadone doses of 2-120 mg/day. Urinary methadone excretion was observed to be significantly affected by pH, in which the ratio of methadone to EDDP was two times higher in acidic urine (P = 0.029). The findings of this study further enhance the guidelines for monitoring of methadone treatment among outpatients. Methadone-to-EDDP ratio in urine was found to be consistent at 24 and 4 h, hence suggesting the possibility that outpatients may be monitored with single urine sample in order to check for compliance. This study which provides data on peak concentrations of methadone and EDDP as well as the ratio of both compounds has added to the body of knowledge regarding pharmacokinetic properties of methadone among heroin-dependent patients under MMT.
    Study site: University Malaya Medical Centre (UMMC), HKL, University Malaya Centre for Addiction Sciences (UMCAS) and Rehabilitation Centre of Al-Rahman Mosque, Kuala Lumpur, Malaysia
    Matched MeSH terms: Substance Abuse Detection/methods
  10. Citartan M, Gopinath SC, Tominaga J, Chen Y, Tang TH
    Talanta, 2014 Aug;126:103-9.
    PMID: 24881539 DOI: 10.1016/j.talanta.2014.03.043
    Label-free-based detection is pivotal for real-time monitoring of biomolecular interactions and to eliminate the need for labeling with tags that can occupy important binding sites of biomolecules. One simplest form of label-free-based detection is ultraviolet-visible-near-infrared (UV-vis-NIR) spectroscopy, which measure changes in reflectivity as a means to monitor immobilization and interaction of biomolecules with their corresponding partners. In biosensor development, the platform used for the biomolecular interaction should be suitable for different molecular recognition elements. In this study, gold (Au)-coated polycarbonate was used as a platform and as a proof-of-concept, erythropoietin (EPO), a doping substance widely abused by the athletes was used as the target. The interaction of EPO with its corresponding molecular recognition elements (anti-EPO monoclonal antibody and anti-EPO DNA aptamer) is monitored by UV-vis-NIR spectroscopy. Prior to this, to show that UV-vis-NIR spectroscopy is a suitable method for measuring biomolecular interaction, the interaction between biotin and streptavidin was demonstrated via this strategy and reflectivity of this interaction decreased by 25%. Subsequent to this, interaction of the EPO with anti-EPO monoclonal antibody and anti-EPO DNA aptamer resulted in the decrease of reflectivity by 5% and 10%, respectively. The results indicated that Au-coated polycarbonate could be an ideal biosensor platform for monitoring biomolecular interactions using UV-vis-NIR spectroscopy. A smaller version of the Au-coated polycarbonate substrates can be derived from the recent set-up, to be applied towards detecting EPO abuse among atheletes.
    Matched MeSH terms: Substance Abuse Detection/methods
  11. Suppiah B, Vicknasingam B, Singh D, Narayanan S
    J Psychoactive Drugs, 2016 Apr-Jun;48(2):86-92.
    PMID: 27014841 DOI: 10.1080/02791072.2016.1156790
    Despite the rise in recreational use of ketamine in Malaysia, there have been no studies of users or of the health-related consequences they face. This study was initiated to examine ketamine use and its health consequences. A structured questionnaire was used to elicit information. A final sample of 127 males was divided into persons who used only ketamine and those who were poly-drug users. Each group was further divided into long-period and short-period users. Urine toxicology screening for ketamine and other illicit drugs commonly used in Malaysia was also done. Our findings corroborate those of earlier studies that link ketamine use to urological problems such as frequent urination, dysuria, incontinence, painful bladder, nocturia, and urinary urgency. A new finding in this study is the significant association between ketamine use and erectile dysfunction, such that higher odds of reporting erectile dysfunction were linked to long-period users. Our findings strengthen the case for early intervention, as ketamine users are drawn from young and unmarried male participants. The association of ketamine use with erectile dysfunction, if substantiated, will help physicians in their diagnosis of erectile dysfunction, particularly among youths.
    Matched MeSH terms: Substance Abuse Detection
  12. Gan CY, Zainuddin Z, Muhamad Noh H, Rahmat R, Mohd Akir F, Mahad NH, et al.
    Forensic Sci Int, 2019 Sep;302:109865.
    PMID: 31279278 DOI: 10.1016/j.forsciint.2019.06.023
    Consumption of curry containing poppy seeds has raised an issue concerning the opiate content in the urine that might exceed the cut-off value (300ng/mL). The main objective of this study was to examine the morphine and codeine contents in the urine of the consumers after partaking poppy seed-enriched curry in. The volunteers were asked to partake: (a) a single meal and their urines were collected within 24h, or (b) Two meals a day for three consecutive days and their urines were collected within 72h. Two different dosages were also tested in this study: (a) low dosage: 1g/100ml curry (containing 138μg of morphine and 66μg of codeine) and (b) high dosage: 5g/100ml curry (containing 690μg of morphine and 330μg of codeine). The subjects were randomised into the groups using the method of stratified randomization with age and gender groups as covariates. A total of 6 subjects was allocated for each group and placebos were used as control. Results showed that all subjects who consumed low dosage of poppy seeds either in single meal or multiple meals experiment were found negative. However, 1 out of 6high dosage subjects was confirmed positive at a period of 3-6h after the consumption of curry in the single meal study. This outlier maybe due to the lack of water consumption after consuming the curry, thus the low volume of urine was collected and the opiate was concentrated in the urine. On the other hand, 5 out of 6high dosage subjects in the multiple meals experiment were found positive. Majority of these subjects were found positive on the second and third day of the experiment after the second curry meal was consumed. The outlier (negative) in this group might be due to the high consumption of water throughout the experiment and the subject's urine volumes and frequency of urine collection were much higher compared to other subjects. From the result of this study, it can be concluded that partaking high dosages of poppy seed in curry could give a positive response (>300ng/ml+uncertainty of measurement) in the urine, and the water consumption after partaking curry has significant influence for the opiate contents in the urine.
    Matched MeSH terms: Substance Abuse Detection
  13. Harun N, Anderson RA, Miller EI
    J Anal Toxicol, 2009 8 6;33(6):310-21.
    PMID: 19653934 DOI: 10.1093/jat/33.6.310
    An ELISA and a liquid chromatography-tandem mass spectrometry (LC-MS-MS) confirmation method were developed and validated for the identification and quantitation of ketamine and its major metabolite norketamine in urine samples. The Neogen ketamine microplate ELISA was optimized with respect to sample and enzyme conjugate volumes and the sample preincubation time before addition of the enzyme conjugate. The ELISA kit was validated to include an assessment of the dose-response curve, intra- and interday precision, limit of detection (LOD), and cross-reactivity. The sensitivity and specificity were calculated by comparison to the results from the validated LC-MS-MS confirmation method. An LC-MS-MS method was developed and validated with respect to LOD, lower limit of quantitation (LLOQ), linearity, recovery, intra- and interday precision, and matrix effects. The ELISA dose-response curve was a typical S-shaped binding curve, with a linear portion of the graph observed between 25 and 500 ng/mL for ketamine. The cross-reactivity of 200 ng/mL norketamine to ketamine was 2.1%, and no cross-reactivity was detected with 13 common drugs tested at 10,000 ng/mL. The ELISA LOD was calculated to be 5 ng/mL. Both intra- (n = 10) and interday (n = 50) precisions were below 5.0% at 25 ng/mL. The LOD for ketamine and norketamine was calculated statistically to be 0.6 ng/mL. The LLOQ values were also calculated statistically and were 1.9 ng/mL and 2.1 ng/mL for ketamine and norketamine, respectively. The test linearity was 0-1200 ng/mL with correlation coefficient (R(2)) > 0.99 for both analytes. Recoveries at 50, 500, and 1000 ng/mL range from 97.9% to 113.3%. Intra- (n = 5) and interday (n = 25) precisions between extracts for ketamine and norketamine were excellent (< 10%). Matrix effects analysis showed an average ion suppression of 5.7% for ketamine and an average ion enhancement of 13.0% for norketamine for urine samples collected from six individuals. A comparison of ELISA and LC-MS-MS results demonstrated a sensitivity, specificity, and efficiency of 100%. These results indicated that a cutoff value of 25 ng/mL ketamine in the ELISA screen is particularly suitable and reliable for urine testing in a forensic toxicology setting. Furthermore, both ketamine and norketamine were detected in all 34 urine samples collected from individuals socializing in pubs by the Royal Malaysian Police. Ketamine concentrations detected by LC-MS-MS ranged from 22 to 31,670 ng/mL, and norketamine concentrations ranged from 25 to 10,990 ng/mL. The concentrations of ketamine and norketamine detected in the samples are most ikely indicative of ketamine abuse.
    Matched MeSH terms: Substance Abuse Detection
  14. Ramli R, Oxley J, Noor FM, Abdullah NK, Mahmood MS, Tajuddin AK, et al.
    J Forensic Leg Med, 2014 Aug;26:39-45.
    PMID: 25066171 DOI: 10.1016/j.jflm.2014.06.007
    Motorcycle fatalities constitute the majority of road traffic deaths in Malaysia. The aims of this study were to describe the pattern of fatal injuries among Klang Valley fatal motorcyclists and to describe the factors associated with fatal (vs non-fatal) injuries.
    Matched MeSH terms: Substance Abuse Detection
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