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1.
Tribulus terrestris is a nutritional supplement highly debated regarding its physiological and actual effects on the organism. The main claimed effect is an increase of testosterone anabolic and androgenic action through the activation of endogenous testosterone production. Even if this biological pathway is not entirely proven, T. terrestris is regularly used by athletes. Recently, the analysis of two female urine samples by GC/C/IRMS (gas chromatography/combustion/isotope-ratio-mass-spectrometry) conclusively revealed the administration of exogenous testosterone or its precursors, even if the testosterone glucuronide/epitestosterone glucuronide (T/E) ratio and steroid marker concentrations were below the cut-off values defined by World Anti-Doping Agency (WADA). To argue against this adverse analytical finding, the athletes recognized having used T. terrestris in their diet. In order to test this hypothesis, two female volunteers ingested 500 mg of T. terrestris, three times a day and for two consecutive days. All spot urines were collected during 48 h after the first intake. The 13C/12C ratio of ketosteroids was determined by GC/C/IRMS, the T/E ratio and DHEA concentrations were measured by GC/MS and LH concentrations by radioimmunoassay. None of these parameters revealed a significant variation or increased above the WADA cut-off limits. Hence, the short-term treatment with T. terrestris showed no impact on the endogenous testosterone metabolism of the two subjects.  相似文献   

2.
In elite sports, indirect testing of testosterone abuse is mainly based on the testosterone over epitestosterone (T/E) ratio. Since this marker is characterized by a small ratio of intra- to inter-individual variation, it is surprising that current anti-doping strategy uses a screening test based on a population-based limit. From a database of more than 15,000 steroid profiles obtained from routine controls, the collection of steroids profiles of 11 elite athletes followed during 2 years, and a longitudinal study involving 17 amateur athletes, 8 of which were orally administrated testosterone undecanoate pills, we selected 12 case studies to represent the possible scenarios to which the anti-doping laboratories are confronted. Various detection strategies at the disposal of the laboratories are employed and discussed, including isotope ratio mass spectrometry (IRMS) analysis and a Bayesian interpretation of the T/E-time profile. The weak sensitivity versus specificity relation of a population-based limit for the T/E ratio is outlined. As a result, we propose a Bayesian screening test whose T/E threshold progressively evolves from a population basis to a subject basis as the number of individual test results increases. We found that this screening test heightens drastically the capacity to detect testosterone abuse, at no additional financial and administrative expenses for anti-doping authorities.  相似文献   

3.
Studying links between triacetone triperoxide (TATP) samples from crime scenes and suspects can assist in criminal investigations. Isotope ratio mass spectrometry (IRMS) and gas chromatography (GC)‐IRMS were used to measure the isotopic compositions of TATP and its precursors acetone and hydrogen peroxide. In total, 31 TATP samples were synthesized with different raw material combinations and reaction conditions. For carbon, a good differentiation and a linear relationship were observed for acetone–TATP combinations. The extent of negative (δ13C) fractionation depended on the reaction yield. Limited enrichment was observed for the hydrogen isotope (δ2H) values of the TATP samples probably due to a constant exchange of hydrogen atoms in aqueous solution. For oxygen (δ18O), the small isotopic range and excess of water in hydrogen peroxide resulted in poor differentiation. GC‐IRMS and IRMS data were comparable except for one TATP sample prepared with high acid concentration demonstrating the potential of compound‐specific isotope analysis. Carbon IRMS has practical use in forensic TATP investigations.  相似文献   

4.
Confirmation of a potential disinterred grave was sought by GC and GC/MS analyses of lipid extracts of whole soils and white particulate matter. Fatty acid profiles and concentrations determined for three of the soils correlated with the deposition of a large amount of exogenous organic matter, most likely adipocere and/or decomposed body fat. Determination of C16:0 and C18:0 fatty acid δ13C values by GC/C/IRMS revealed the input to be isotopically distinct from common British domesticated animals, plotting closely to values determined for adipose fat obtained from of a murder victim. By considering the difference between δ13C values (Δ13C18:0–16:0) a potential isotopic proxy for identifying the source of adipocere (human) and adipose tissue was proposed.  相似文献   

5.
Between December 2007 and January 2008, people suffered from food poisoning in the Japanese prefectures of Chiba and Hyogo after eating frozen dumplings (gyoza) produced in China, which had very high concentrations (1490–19,290 ppm) of methamidophos (O,S‐dimethyl phosphoramidothioate). Thus, we measured the stable carbon isotope ratio of methamidophos using GC/C/IRMS to identify the source. We analyzed seven methamidophos reagents and one Chinese agricultural methamidophos chemical (MTD600) that contained many impurities. The δ13C values of the seven methamidophos reagents and MTD600 ranged from ?49.23‰ to ?31.90‰, with an average SD of 0.20‰, very high precision. This difference (17.33‰) was very large compared with that in previous reports and may be attributable to the material itself and the chemical processing of methamidophos. Criminals can easily obtain pesticides such as methamidophos; therefore, it is very important to identify the pesticide source and distribution route using stable isotopic science in the future.  相似文献   

6.
A simple means of detecting the abuse of steroids that also occur naturally is a problem facing doping control laboratories. Specific markers are required to allow the detection of the administration of these steroids. These markers are commonly measured using a set of data obtained from the screening of samples by gas chromatography-mass spectrometry (GC-MS). Doping control laboratories further need to confirm identified abuse using techniques such as gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). An interesting urinary species was found while following the pharmacokinetics and changes to the steroid profile from single and multiple oral doses of the International Olympic Committee/World Anti Doping Agency (IOC/WADA) prohibited substance, dehydroepiandrosterone (DHEA). The urine samples collected from the administration studies were subject to GC-MS and GC-C-IRMS steroid analysis following cleanup by solid phase extraction techniques. A useful urinary product of DHEA administration was detected in the urine samples from each of the administration studies and was identified by GC-MS experiments to be 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo). This compound occurs naturally but the concentrations of 3alpha,5-cyclo were elevated following both the single DHEA administration (up to 385 ng/mL) and multiple DHEA administrations (up to 1240 ng/mL), in relation to those observed prior to these administrations (70 and 80 ng/mL, respectively). A reference distribution of urine samples collected from elite athletes (n = 632) enabled the natural concentration range of 3alpha,5-cyclo to be established (0-280 ng/mL), with a mean concentration of 22 ng/mL. Based on this an upper 3alpha,5-cyclo concentration limit of 140 ng/mL is proposed as a GC-MS screening marker of DHEA abuse in athletes. GC-C-IRMS analysis revealed significant 13C depletion of 3alpha,5-cyclo following DHEA administration. In the single administration study, the delta13C value of 3alpha,5-cyclo changed from -24.3 per thousand to a minimum value of -31.1 per thousand at 9 h post-administration, before returning to its original value after 48 h. The multiple administration study had a minimum delta13C 3alpha,5-cyclo of -33.9 per thousand during the administration phase in contrast to the initial value of -24.2 per thousand. Preliminary studies have shown 3alpha,5-cyclo to most likely be produced from DHEA sulfate found at high levels in urine. The complementary use of GC-MS and GC-C-IRMS to identify new markers of steroid abuse and the application of screening criteria incorporating such markers could also be adapted by doping control laboratories to detect metabolites of androstenedione, testosterone and dihydrotestosterone abuse.  相似文献   

7.
Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require criteria that allow endogenous steroids to be distinguished from their synthetic analogues in urine. Methodology based on "looking outside the metabolic box" was used in this study to identify diagnostic urinary markers of 4-androstenediol (4-ADIOL) administration. Androst-2,4-diene-17-one and androst-3,5-diene-17-one are proposed to be formed in urine from acid-catalyzed hydrolysis of 4-ADIOL sulfoconjugate, a major phase II metabolic product of 4-ADIOL. The presence of these markers in the routine gas chromatography-mass spectrometry (GC-MS) steroid screen was suitable to identify samples requiring confirmation by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) - to measure the carbon isotope ratio (δ(13)C) of the androstdiene markers and confirm their likely synthetic origin based on depleted (13)C content.  相似文献   

8.
In this study, δ13C values of six cocaine samples were identified and classified using a single quadrupole mass spectrometer and an isotope ratio mass spectrometry (IRMS) as simultaneous gas chromatography detectors. Our instrument modification is simple to use and is useful (i) when the sample is of limited size or can only be injected once, (ii) to help identify peaks in a complicated IRMS chromatogram, and (iii) to help differentiate very simple systems when impurity profiling is not possible. The EI-MS confirmed the identity of cocaine in each sample. The IRMS data distinguished 12 of the 15 possible pair-wise comparisons at the 95% CL. Three samples could not be differentiated by their δ13C ratios for cocaine. ANOVA demonstrated that the measurement variance was consistently larger than the sample variance. As the δ13C values clearly show, this technique enables the exclusion of a potential common source even when two samples have otherwise identical chemical and physical properties.  相似文献   

9.
The body of a 30‐year‐old woman was found in Como lake at a depth of about 120 meters in her own car after 3 years of immersion. The aim of this study was to evaluate psychoactive drugs as well as alcohol biomarkers in biological matrices. The following analyses were initially performed: GC‐MS systematic toxicological analysis on biological fluids and tissues; GC‐MS analysis of drugs of abuse on pubic hair; direct ethanol metabolite determination in pubic hair by LC‐MS/MS. After 7 years, the samples, that had been stored at ?20°C, were re‐analyzed and submitted to an LC‐MS/MS targeted screening method, using multiple reaction monitoring mode. These analyses detected citalopram (150–3000 ng/mL), desmethylcitalopram (50–2300 ng/mL), clotiapine (20–65 ng/mL), and ethyl glucuronide (97 pg/mg). The methods showed an acceptable reproducibility, and the concentrations of citalopram and desmethylcitalopram calculated through the two analytical techniques did not significantly differ in biological fluids.  相似文献   

10.
Anti-doping authorities have high expectations of the athlete steroidal passport (ASP) for anabolic-androgenic steroids misuse detection. However, it is still limited to the monitoring of known well-established compounds and might greatly benefit from the discovery of new relevant biomarkers candidates. In this context, steroidomics opens the way to the untargeted simultaneous evaluation of a high number of compounds. Analytical platforms associating the performance of ultra-high pressure liquid chromatography (UHPLC) and the high mass-resolving power of quadrupole time-of-flight (QTOF) mass spectrometers are particularly adapted for such purpose. An untargeted steroidomic approach was proposed to analyse urine samples from a clinical trial for the discovery of relevant biomarkers of testosterone undecanoate oral intake. Automatic peak detection was performed and a filter of reference steroid metabolites mass-to-charge ratio (m/z) values was applied to the raw data to ensure the selection of a subset of steroid-related features. Chemometric tools were applied for the filtering and the analysis of UHPLC-QTOF-MS(E) data. Time kinetics could be assessed with N-way projections to latent structures discriminant analysis (N-PLS-DA) and a detection window was confirmed. Orthogonal projections to latent structures discriminant analysis (O-PLS-DA) classification models were evaluated in a second step to assess the predictive power of both known metabolites and unknown compounds. A shared and unique structure plot (SUS-plot) analysis was performed to select the most promising unknown candidates and receiver operating characteristic (ROC) curves were computed to assess specificity criteria applied in routine doping control. This approach underlined the pertinence to monitor both glucuronide and sulphate steroid conjugates and include them in the athletes passport, while promising biomarkers were also highlighted.  相似文献   

11.
Several studies have provided evidence that antisocial, borderline and narcissistic personality traits of intimate partner violence (IPV) perpetrators significantly increase proneness to violence. In addition, an imbalance between testosterone (T) and cortisol (C) levels has been observed in this population, making individuals prone to violence. We aimed to establish whether IPV perpetrators differ in personality traits, T/C ratio and anger expression from controls, and also to examine the moderating role of the T/C ratio in the relationship between personality traits and anger expression. The sample consisted of 16 IPV perpetrators and 20 controls. T/C ratio was obtained as the quotient between salivary T and C levels. Anger expression and personality traits were measured with STAXI-2 and MCMI-III, respectively. Our results indicate that IPV perpetrators have higher antisocial, borderline and narcissistic personality traits and anger expression than controls. Nonetheless, they did not differ in basal T/C ratio. Finally, only in IPV perpetrators there was a positive relationship between these variables, the T/C ratio playing a moderating role in the relationship of antisocial and borderline traits with anger expression. In IPV perpetrators the T/C ratio may explain why certain personality traits are associated with high risk of becoming violent.  相似文献   

12.
Pharmacokinetic studies of psilocybin in humans have shown the rapid dephosphorylation of psilocybin to psilocin with further conversion to 4-hydroxy-tryptophole (4HT) and 4-hydroxyindole-3-acetic acid (4HIAA) in plasma. Our study shows that psilocin also undergoes conjugation and can be found in the urine as the psilocin-glucuronide conjugate. Recoveries after enzymatic hydrolysis of the urine with beta-glucuronidase (Helix Pomatia or E. Coli) when compared to non-hydrolyzed urine confirmed the presence of the glucuronide. Detection of psilocin from hydrolyzed and extracted samples was optimized for GC/MS by derivatization with MSTFA. The method developed allows for the detection of psilocin in urine with a limit of quantitation of 10 ng/mL, based on 5 mL of spiked urine. Using this method, our laboratory has confirmed the presence of psilocin in 6 out of 8 urine samples, with concentrations ranging from 10 ng/mL to greater than 200 ng/mL. Before implementation of the hydrolysis and derivatization steps, our limit of detection was 200 ng/mL, based on spiked urine standards. No case samples were positive without hydrolysis and derivatization.  相似文献   

13.
The concentrations of alcohol in blood (BAC) and two successive urine voids (UAC) from 100 drunk drivers were compared with the concentration of ethyl glucuronide (EtG), a minor metabolite of ethanol in urine, and the urinary creatinine content as an indicator of dilution. The subjects consisted of 87 men with mean age 42.2+/-14.2 years (+/-standard deviation, S.D.) and 13 women with mean age 42.5+/-14.4 years. Ethanol was measured in blood and urine by headspace gas chromatography (GC) and EtG was determined in urine by liquid chromatography-mass spectrometry (LC-MS). The mean UAC was 2.53+/-1.15g/l for first void compared with 2.35+/-1.17g/l for second void, decreasing by 0.18+/-0.24g/l on average (P<0.001 in paired t-test). The ratios of UAC/BAC were 1.35+/-0.25 for first void and 1.20+/-0.16 for second void and the difference of 0.15+/-0.27 was statistically significant (P<0.001). The UAC/BAC ratio was not correlated with creatinine content of the urine specimens, whereas the concentration of urinary EtG was positively correlated with creatinine (r=0.64 for first void and r=0.62 for second void). The UAC was not correlated with urinary EtG directly (r=-0.03 for first void and r=0.08 for second void) but after adjusting for the relative dilution of the specimens (EtG/creatinine ratio) statistically significant positive correlations were obtained (r=0.58 for first void and r=0.57 for second void). The dilution of the urine, as reflected in creatinine content, is important to consider when EtG measurements are interpreted. The excretion of EtG in urine, like glucuronide conjugates of other drugs, is influenced by diuresis. EtG represents a sensitive and specific marker of acute alcohol ingestion with applications in clinical and forensic medicine.  相似文献   

14.
The case of seven urine samples collected for anti-doping purposes during a cycling stage race with moderately elevated testosterone and epitestosterone ratio (T/E) is reported. The very low probability of having all seven urine samples with such similar elevated T/E ratio (from 3.2 to 4.7) was very suspicious. Different pattern classification tools were tested to categorize the most similar steroid profiles, but none of the models enabled a clear classification of the different urine samples. Subsequently, genetic profiling of all urine samples was performed and demonstrated that three of the seven samples were collected from the same cyclist. Finally, the International Federation confirmed DNA profiling results. This suggests that urinary steroid data using several methodologies are not appropriate for identification purposes and to an extent not unique to individuals.  相似文献   

15.
11-Nor-Delta(9)-carboxy tetrahydrocannabinol glucuronide (THCCOOglu) is a major metabolite of tetrahydrocannabinol in blood. Despite its mass spectrometric identification already in 1980, further physicochemical data of THCCOOglu have not been established. Therefore, the octanol/buffer partition coefficient P and the blood to plasma ratio b/p for THCCOOglu concentrations of 100 and 500ng/ml were investigated. Protein binding of the glucuronide was established from spiked albumin solutions at a level of 250ng/ml as well as from authentic samples. The data were compared to those of 11-nor-Delta(9)-carboxy tetrahydrocannabinol (THCCOOH). In addition, the short-term stability of THCCOOglu in plasma at different storage temperatures was studied. Analysis was performed by LC/MS/MS. The glucuronide partition coefficient P (mean: 17.4 and 18.0 for 100 and 500ng/ml, respectively) was unexpectedly lipophilic at pH 7.4. Its blood to plasma ratios averaged 0.62 and 0.68 at 100 and 500ng/ml, respectively. THCCOOglu was highly reversibly bound to albumin (mean: 97%), and the mean fraction bound did not differ from that determined from authentic samples. THCCOOglu degraded even at a storage temperature of 4 degrees C and THCCOOH was identified as a major decomposition product.  相似文献   

16.
本文对测定血痕中睾酮量(T)和全血蛋白量(P),及T/P的比值来判断血痕性别的可能性进行了探讨.通过测定102名健康成年人血痕(男性57名,女性45名),得出本法对男性血痕的肯定率为80.7%,对女性血痕的肯定率为88.9%.实验中还观察到时间因素及某些环境因素(霉变)能使两性血痕T/P值降低.  相似文献   

17.
Most substances used for doping in sport are legitimate pharmaceutical products deviated from their intended therapeutic applications. One of the major challenges for anti-doping authorities, in anticipation of future doping trends, is to assess the doping potential of drugs in development by the health industry and to timely develop anti-doping analytical methods to detect their abuse before such drugs become available to athletes intending to use them as doping agents. In this regard, the World Anti-Doping Agency (WADA) has recently consolidated several agreements with representatives from the pharmaceutical sector in order to establish a framework of collaboration and to facilitate the identification and transfer of information on drugs in development. The context of the collaborative effort between WADA and the pharmaceutical and biotechnology industries, as well as the role of drug regulatory agencies in an integrated process in support of the fight against doping in sport are described in this article.  相似文献   

18.
The elimination time of illicit drugs and their metabolites is of both clinical and forensic interest. In order to determine the elimination time for various drugs and their metabolites we recruited 52 volunteers in a protected, low-step detoxification program. Blood samples were taken from each volunteer for the first 7 days, daily, urine sample for the first 3 weeks, daily. Urine was analyzed using a fluorescence-polarization immunoassay (FPIA) and gas chromatography/mass spectrometry (GC/MS), serum using GC/MS. The elimination times of the drugs and/or their metabolites in urine and serum as well as the tolerance intervals/confidence intervals were determined. Due to the sometimes extremely high initial concentrations and low cut-off values, a few of the volunteers had markedly longer elimination times than those described in the literature. The cut-off values were as follows: barbiturates II (200ng/ml), cannabinoids (20ng/ml), cocaine metabolites (300ng/ml), opiates (200ng/ml). GC/MS detected the following maximum elimination times: total morphine in urine up to 270.3h, total morphine and free morphine in serum up to 121.3h, monoacetylmorphine in urine up to 34.5h, 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH) in urine up to 433.5h, THC-COOH in serum up to 74.3h, total codeine in urine up to 123h, free codeine in urine up to 97.5h, total codeine in serum up to 29h, free codeine in serum up to 6.3h, total dihydrocodeine (DHC) in urine up to 314.8h, free DHC in urine up to 273.3h, total and free DHC in serum up to 50.1h. Cocaine and its metabolites were largely undetectable in the present study.  相似文献   

19.
We described the findings of a study into the post-mortem redistribution (PMR) of 76 drugs found in 129 drug-related cases between 2006 and 2009. Seventy six drugs (psychotropic drugs (n=14), antidepressants (n=9), sedatives (n=6) and so on) were simultaneously quantified in cardiac and peripheral blood by gas chromatography-mass spectrometry (GC/MS) or liquid chromatography-tandem mass spectrometry (LC/MS/MS). The absence, possibility or presence of PMR of drugs was determined according to the ratios of cardiac to femoral blood concentrations (C/P ratios). Proxyphylline (C/P ratio: 0.85) showed no PMR; carbamazepine was not subject to PMR; a potential for PMR of lorazepam and mirtrazapine cannot be excluded; chlordiazepoxide is subject to PMR; acetaminophen and alprazolam exhibit minimal PMR; amitriptyline and benztropine exhibit PMR. Codeine (C/P ratio: 4.9), zolpidem (C/P ratio: 3.74), chlorpromazine (C/P ratio: 2.97), fluoxetine (C/P ratio: 2.83) and propranolol (C/P ratio: 2.72) had the largest C/P ratios. Postmortem drug concentrations showed variations depending on sampling sites and characteristics of the drugs. It is continuously necessary to analyze commonly used or abused drugs in simultaneously collected cardiac and peripheral blood to establish significant reference values for PMR. These findings can be used to reach a conclusion about the cause and manner of death.  相似文献   

20.
Zeng LB  Chen LK  Hu XL  Chen L  Wang XS  Zhang YR 《法医学杂志》2006,22(2):130-132
目的采用免疫竞争法原理,建立一种简便快速检测丁丙诺啡的方法。方法将20nm胶体金颗粒标记的抗丁丙诺啡单克隆抗体,均匀浸在吸水玻璃纤维上,将丁丙诺啡-BSA和纯化后的羊抗鼠IgG多克隆抗体在硝酸纤维薄膜分别划1mm宽的检测线(T线)和质控线(C线),制成丁丙诺啡胶体金标记单克隆抗体免疫层析检测条,并组装成检测板。结果以GC/MS为标准对照,100例样品检测结果显示,本检测板的准确率为99.0%。丁丙诺啡胶体金标记单克隆抗体免疫层析检测板在对45种药(毒)物的测试中,仅识别丁丙诺啡及其主要代谢产物。结论丁丙诺啡胶体金标记单克隆抗体免疫层析检测板在5min内可检出样品中的丁丙诺啡及其代谢物,检测丁丙诺啡的阈值为100ng/mL。  相似文献   

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