Drug Testing and Analysis最新文献_第8页

Distinguishing Between Oral and Transdermal Administration Routes of Methyltestosterone Through Human Urine and Dried Blood Spot Analyses for Doping Control Purposes 甲基睾酮经口服和经皮给药途径的鉴别及干血检测。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-10-23 DOI: 10.1002/dta.3962

Masato Okano, Yuma Watanabe, Asami Miyamoto, Masanori Ota, Mitsuhiko Sato

{"title":"Distinguishing Between Oral and Transdermal Administration Routes of Methyltestosterone Through Human Urine and Dried Blood Spot Analyses for Doping Control Purposes","authors":"Masato Okano, Yuma Watanabe, Asami Miyamoto, Masanori Ota, Mitsuhiko Sato","doi":"10.1002/dta.3962","DOIUrl":"10.1002/dta.3962","url":null,"abstract":"<div>\u0000 \u0000 <p>Unintentional doping violations have been reported after secondary skin exposure, including partner contact or contact sports. Methyltestosterone (MT), an anabolic androgenic steroid on the World Anti-Doping Agency Prohibited List, is readily available in Japan as an over-the-counter topical hair-growth preparation and as oral tablets. This study evaluated whether transdermal absorption of MT can be distinguished from oral administration using human urine and dried blood spot (DBS) analyses. Ten men received MT once daily for five consecutive days (five oral, five transdermal). The urinary tetrahydro-metabolites 17α-methyl-5α-androstane-3α,17β-diol (5α-THMT) and 17α-methyl-5β-androstane-3α,17β-diol (5β-THMT) were detectable within hours after administration for both routes. Following transdermal administration, 5α-THMT remained detectable up to 97 h after the final administration, whereas, after oral administration, 5β-THMT persisted longer, up to 265 h. Transdermal application produced a marked increase in 5α-THMT, consistent with high 5α-reductase activity in skin, yielding a significantly higher 5α-THMT/5β-THMT ratio than after oral administration. Nonetheless, individuals with inherently high 5α-reductase activity may exhibit elevated ratios even after oral dosing, warranting careful interpretation. In DBS after oral dosing, parent MT was generally detectable up to 24 h, providing a shorter detection window than urinary tetrahydro-metabolites. Overall, combining urine (tetrahydro-metabolites) and DBS (parent MT) analyses enables effective detection of MT use and supports differentiation of administration routes.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"24-31"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145342168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluating the Testosterone-to-Luteinizing Hormone Ratio in Male Anti-Doping Serum Samples: Results From a Transdermal Testosterone Administration Trial and Field Collected Samples 评估男性抗兴奋剂血清样本中睾酮和黄体生成素的比例：来自经皮睾酮给药试验和现场采集样本的结果。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-10-14 DOI: 10.1002/dta.3959

Jenna M. Goodrum, Vinod S. Nair, Andre K. Crouch, Daniel Eichner, Geoffrey D. Miller

{"title":"Evaluating the Testosterone-to-Luteinizing Hormone Ratio in Male Anti-Doping Serum Samples: Results From a Transdermal Testosterone Administration Trial and Field Collected Samples","authors":"Jenna M. Goodrum, Vinod S. Nair, Andre K. Crouch, Daniel Eichner, Geoffrey D. Miller","doi":"10.1002/dta.3959","DOIUrl":"10.1002/dta.3959","url":null,"abstract":"<div>\u0000 \u0000 <p>The serum testosterone-to-luteinizing hormone (T/LH) ratio has previously been suggested as a sensitive marker of testosterone use in an anti-doping setting. When measured with an automated immunoassay platform, this ratio represents a quick and cost-effective screening biomarker to further direct isotope ratio mass spectrometry (IRMS) testing efforts in concurrently collected urine samples to confirm testosterone abuse. To evaluate the practicality of implementing the serum T/LH ratio for routine use, testosterone values in 356 serum samples were compared between a “gold-standard” LC–MS/MS method and an automated immunoassay method. Excellent correlation and minimal bias between the two methods were observed, highlighting the validity of the immunoassay method. Next, a testosterone administration study utilizing a transdermal delivery route was conducted to compare the effectiveness of the serum T/LH ratio to the currently used serum testosterone to androstenedione (T/A4) and urinary testosterone to epitestosterone (T/E) ratios. The serum T/LH ratio was more sensitive than the T/A4 ratio and showed similar sensitivity to the urinary T/E ratio with high interindividual variability. Finally, T/LH analysis was conducted on 626 capillary serum samples collected in the field from male Ultimate Fighting Championship athletes. Of the three samples that showed elevated T/LH ratios in this pool, two of the corresponding urine samples were IRMS positive, one of which showed an unremarkable urinary T/E ratio and relatively normal steroid profile. These results indicate serum T/LH ratio monitoring provides a beneficial addition to the anti-doping tool kit and can improve urinary IRMS testing recommendations.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"9-15"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145290440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Carbon Isotope Ratio Analysis of Urinary Steroids Following Extensive Cleanup and Formylation 广泛清除和甲酰化后尿类固醇的碳同位素比分析。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-11-20 DOI: 10.1002/dta.3971

Tim Sobolevsky, Mustafa Cittan, Elizabeth Ahrens

{"title":"Carbon Isotope Ratio Analysis of Urinary Steroids Following Extensive Cleanup and Formylation","authors":"Tim Sobolevsky, Mustafa Cittan, Elizabeth Ahrens","doi":"10.1002/dta.3971","DOIUrl":"10.1002/dta.3971","url":null,"abstract":"<div>\u0000 \u0000 <p>Gas chromatography–combustion–isotope ratio mass spectrometry (GC-C-IRMS) is the method of choice to detect the abuse of synthetic forms of naturally occurring steroids for doping control purposes. GC-C-IRMS relies on a multistep sample cleanup to ensure each target analyte peak is chromatographically pure before combustion. To achieve that, liquid–liquid or solid phase extraction (SPE) is commonly used in combination with preparative liquid chromatography (LC).</p>\u0000 <p>In this work, a procedure for isolation, purification, and analysis of endogenous steroids by GC-C-IRMS was developed and validated. The key elements were successive application of strong cation and strong anion exchange SPE with enzymatic hydrolysis in between to strip the ionic species from urine and decrease matrix complexity prior to LC cleanup; preparative two-dimensional LC, where only the testosterone fraction required secondary purification (40 min total run time per sample); and derivatization of selected fractions with formic acid to yield formate esters, followed by GC-C-IRMS analysis. Formylation afforded excellent separation between 5α- and 5β-androstanediols and simplified the detection of the endogenous reference compound pregnanetriol by converting it to a volatile artifact, tentatively identified as 3α,20-diformoxy-17-methyl-18-nor-5β,17α-pregn-13-ene.</p>\u0000 <p>The overall method performance benefited from the customization of the GC-C-IRMS combustion interface, which improved robustness and facilitated the transfer of sample components into the hot zone of the oxidation reactor, minimizing peak tailing. The former was achieved by keeping the oxygen flow through the reactor at all times, obviating the need for periodic oxidation, and the latter—by implementing a direct capillary-in-capillary connection of the chromatographic column to the oxidation reactor.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"170-186"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145561954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mapping of the Pharmacological Effect of Prohibited Substances and Methods to Athletic Physiological Characteristics 禁用物质的药理作用及其对运动员生理特征的影响。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-10-28 DOI: 10.1002/dta.3958

Gregory Hayward, Lorenzo Gaborini, Neil Robinson, Mark Stuart, David Mottram

{"title":"Mapping of the Pharmacological Effect of Prohibited Substances and Methods to Athletic Physiological Characteristics","authors":"Gregory Hayward, Lorenzo Gaborini, Neil Robinson, Mark Stuart, David Mottram","doi":"10.1002/dta.3958","DOIUrl":"10.1002/dta.3958","url":null,"abstract":"<div>\u0000 \u0000 <p>This study presents a novel physio-pharmacological framework for assessing the potential performance-enhancing effects of substances and methods included in the 2022 World Anti-Doping Agency (WADA) Prohibited List across 160 Olympic sport disciplines. An expert panel evaluated 31 consolidated pharmacological categories for their capacity to enhance performance across six core physiological athletic demands. Using a calibrated scoring function and bilinear interpolation, we mapped these effects to each sport's dominant physiological profile. Findings confirmed the well-known ergogenic effects of anabolic agents and erythropoietins for power and endurance-based sports, respectively, including the general ergolytic effects of narcotics and cannabinoids. Moreover, the methodology can be used to evaluate any new sport or substance given their respective physiological demands. The study underscores the need for targeted anti-doping strategies, suggesting that risk assessment and test distribution planning should be aligned with sport-specific physiological demands and the relative performance advantages conferred by different doping strategies. This summary of the current physiological knowledge and pharmacological knowledge has the potential to enhance detection efficiency, optimize resource allocation, and refine prohibited substance screening in elite sport.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"51-59"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145375771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Identification of Metabolites for the Novel 5α-Reductase Inhibitor Epristeride In Vitro and Its Potential Impact on Doping Testing 新型5α-还原酶抑制剂Epristeride体外代谢物鉴定及其对兴奋剂检测的潜在影响

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-11-16 DOI: 10.1002/dta.3969

Zhongquan Li, Bing Liu, Yirang Wang, Jiahui Cheng, Rodrigo Aguilera, Xiaojun Deng, Qing Chen, Peijie Chen

{"title":"Identification of Metabolites for the Novel 5α-Reductase Inhibitor Epristeride In Vitro and Its Potential Impact on Doping Testing","authors":"Zhongquan Li, Bing Liu, Yirang Wang, Jiahui Cheng, Rodrigo Aguilera, Xiaojun Deng, Qing Chen, Peijie Chen","doi":"10.1002/dta.3969","DOIUrl":"10.1002/dta.3969","url":null,"abstract":"<div>\u0000 \u0000 <p>Epristeride, a novel noncompetitive inhibitor of Type II 5α-reductase, has emerged as a potential therapeutic alternative for benign prostatic hyperplasia (BPH). Given that other 5α-reductase inhibitors, such as finasteride and dutasteride, are already monitored for their potential impact on doping control, comprehensive metabolic studies of epristeride are crucial for antidoping. This study investigates the metabolic pathways and metabolites of epristeride using in vitro microsome models, offering preliminary insights into the pharmacokinetics of this drug. Metabolite profiling was performed using liquid chromatography–high resolution mass spectrometry (LC-HRMS), with data acquisition facilitated by Xcalibur 4.2 software and metabolite identification facilitated by Compound Discoverer 3.3. By employing network pharmacology, the potential targets of epristeride are predicted. The binding energy is calculated using AutoDock Vina software to predict its impact on steroid metabolism. The study proposed three primary metabolites of epristeride: two Phase I oxidation products (M1 and M2) and one Phase II glucuronidation product (M3). Pathway analysis revealed that among the five CYP450 isoforms examined, CYP3A4 played a dominant role. The docking results tentatively elucidated five key target proteins (ESR1, CYP19A1, STAT3, AKR1C3, and CYP17A1) with low binding energies, indicating stable interactions. Notably, Phase I metabolites (M1 and M2) showed significant binding potential with these targets, whereas the Phase II metabolite (M3) exhibited lower binding stability. These findings provide a detailed understanding of epristeride's metabolic pathways and its potential biological impacts, offering valuable insights for monitoring its presence as a confounding factor in doping control.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"85-95"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145533914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Oxidative Processes to Transform and Degrade Amphetamine-Type Stimulants: Alternatives to Incineration 转化和降解苯丙胺类兴奋剂的氧化过程：焚烧的替代品。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-11-17 DOI: 10.1002/dta.3965

Alexandra L. Mercieca, Morgan Alonzo, Scott Chadwick, Andrew M. McDonagh

{"title":"Oxidative Processes to Transform and Degrade Amphetamine-Type Stimulants: Alternatives to Incineration","authors":"Alexandra L. Mercieca, Morgan Alonzo, Scott Chadwick, Andrew M. McDonagh","doi":"10.1002/dta.3965","DOIUrl":"10.1002/dta.3965","url":null,"abstract":"<div>\u0000 \u0000 <p>Although incineration is currently the primary method for the disposal of seized illicit drugs, alternative methods for the disposal of illicit drugs may be necessary to provide safer and more accessible alternatives. Chemical oxidation processes have been identified as a promising alternative method to degrade illicit drugs. Using commercially available reagents and established industry processes, chemical degradation holds potential as an alternative drug disposal technique. This study investigated the oxidants ozone, sodium hypochlorite, trichloroisocyanuric acid, hydrogen peroxide, OXONE, sodium percarbonate, and peracetic acid for their potential to degrade illicit amphetamine-type stimulants using β-phenethylamine (PEA) as an exploratory analog. Oxidants and conditions that showed the highest degradation efficiency with PEA were applied to methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyamphetamine (MDA). Transformation products were identified using gas chromatography–mass spectrometry, and degradation was quantified using a fit-for-purpose method via liquid-chromatography quadrupole time-of-flight mass spectrometry.</p>\u0000 <p>Of the oxidants explored, ozone performed the best, leading to high degradation efficiencies of methamphetamine (95%), amphetamine (86%), MDMA (100%), and MDA (100%) after 72 h of exposure. Sodium hypochlorite was also highly effective for the degradation of methamphetamine and amphetamine, while trichloroisocyanuric acid was particularly effective for MDMA and MDA. All the major transformation products of degradation were tentatively identified, with only one of 10 listed as a controlled, scheduled, or restricted substance. This research demonstrates how chemical degradation can provide a novel alternative to incineration for the destruction of amphetamine-type stimulants, providing a sustainable, long-term, and accessible method of illicit drug disposal.</p>\u0000 </div>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"96-107"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145538290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Further Insights Into the Metabolism of LGD-4033 in Human Urine. Part 2. A New Minor Metabolite With Antagonistic Activity on the Androgen Receptor Can Indicate Recent Substance Intake 人类尿液中LGD-4033代谢的进一步研究第2部分。一种新的对雄激素受体具有拮抗活性的微量代谢物可以指示最近的物质摄入。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-11-19 DOI: 10.1002/dta.70005

Yiannis S. Angelis, Panagiotis Sakellariou, Annekathrin M. Keiler, Mario Thevis, Andreas Thomas, Kevin Lam, Gerhard Wolber, Ariadni Vonaparti, Sven Voss, Michael Petrou, Emmanuel N. Pitsinos

{"title":"Further Insights Into the Metabolism of LGD-4033 in Human Urine. Part 2. A New Minor Metabolite With Antagonistic Activity on the Androgen Receptor Can Indicate Recent Substance Intake","authors":"Yiannis S. Angelis, Panagiotis Sakellariou, Annekathrin M. Keiler, Mario Thevis, Andreas Thomas, Kevin Lam, Gerhard Wolber, Ariadni Vonaparti, Sven Voss, Michael Petrou, Emmanuel N. Pitsinos","doi":"10.1002/dta.70005","DOIUrl":"10.1002/dta.70005","url":null,"abstract":"<p>Using a targeted metabolic investigation approach, a new, previously undescribed metabolite, which is a pyrrole derivative of LGD-4033, has been detected and coded as <b>M8</b>. This metabolite can be detected in postadministration human urine samples up to 6 days after administration. It has also been detected in post-administration samples, mimicking supplement contamination, after repeated 10 μg doses detectable for ≥ 120 h after administration. Given <b>M8's</b> structural similarity to LGD-4033, its androgen receptor (AR) agonist/antagonist properties were studied using <i>in silico</i> molecular docking and functional in vitro AR transactivation assays in the PC3(AR)<sub>2</sub> cell model, alongside other selected LGD-4033 metabolites. The results indicate that <b>M8</b> can act as a potent AR antagonist, whereas <b>M2c</b> was reconfirmed as a potent AR agonist. Therefore, we propose the inclusion of <b>M2c</b> in ITP doping control methods, as it could be used as an LGD-4033 alternative and may be introduced into the black market. Additionally, the detection of <b>M8</b>, which is an early-stage excreted metabolite, is valuable for estimating sample collection time relative to LGD-4033 intake. When combined with the evaluation of other long-term metabolites like M5b, M5a, M2c, and M2d, <b>M8</b> detection can aid in distinguishing adverse analytical findings, associated abuse through regular dosing, from unintentional doping caused by certain contamination scenarios or abuse through microdosing.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"159-169"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.70005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145555976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Toxic Tear Gas 2-Chloroacetophenone (CN) Forms Adducts With Endogenous Plasma Thiols In Vitro Valuable as Biomarkers of Exposure 有毒催泪瓦斯2-氯苯乙酮（CN）与内源性血浆硫醇形成加合物，作为暴露的生物标志物。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-11-04 DOI: 10.1002/dta.3964

Paula Helena Sieber, Dirk Steinritz, Franz Worek, Harald John

{"title":"Toxic Tear Gas 2-Chloroacetophenone (CN) Forms Adducts With Endogenous Plasma Thiols In Vitro Valuable as Biomarkers of Exposure","authors":"Paula Helena Sieber, Dirk Steinritz, Franz Worek, Harald John","doi":"10.1002/dta.3964","DOIUrl":"10.1002/dta.3964","url":null,"abstract":"<p>As the tear gas of the highest toxicity, 2-chloroacetophenone (CN) poses a potential threat for exposed individuals. Several fatality cases following exposure to CN are documented, but an unambiguous identification of CN exposure is still missing. Thus, we herein present the identification of in vitro reaction products between CN and endogenous molecules useful as biomarkers. After incubation of human plasma with CN, diverse acetophenone (<i>AcPhen</i>)-adducts were formed with the small molecule thiols homocysteine (HCys), glutathione (GSH), and cystine (Cys-Cys). All adducts were detected by microbore liquid chromatography-electrospray ionization high-resolution tandem mass spectrometry (μLC-ESI MS/HRMS) working in the parallel reaction monitoring (PRM) mode and were characterized as potential biomarkers of CN exposure. Time- and concentration-dependent adduct formations were investigated, and the stability of <i>AcPhen</i>-adducts in plasma during 4 freeze-and-thaw cycles and in the autosampler was tested. The limit of identification (LOI) of identified <i>AcPhen</i>-adducts in vitro was found at about 6 μM (concentration of CN in plasma) but showed quite limited in vitro stability. The <i>AcPhen</i>-adducts herein presented might be beneficial for future studies addressing CN exposure in vivo.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"74-84"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.3964","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145443640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Detection of Nandrolone Decanoate and Its Metabolites in Equine Hair After Intramuscular Administration 马毛肌注后癸酸诺龙及其代谢物的检测。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-11-19 DOI: 10.1002/dta.70001

Yat-Ming So, Wai Him Kwok, Stella M. S. Yuen, Celia O. L. Wong, Terence S. M. Wan, Emmie N. M. Ho

引用次数: 0

A Meta-Analysis of International Flunixin Pharmacokinetics in Horses: Toward Regulatory Harmonization and Individualized Detection Times Using Bayesian Paradigm 马体内氟尼辛国际药代动力学荟萃分析：采用贝叶斯范式实现监管协调和个性化检测时间。

IF 2.7 3区医学

Drug Testing and Analysis Pub Date : 2026-01-12 Epub Date: 2025-10-25 DOI: 10.1002/dta.3961

Taisuke Kuroda, Heather K. Knych, Glenys K. Noble, Yohei Minamijima, Gary Ngai-Wa Leung, Motoi Nomura, Fumiaki Mizobe, Yuhiro Ishikawa, Kanichi Kusano, Pierre-Louis Toutain

{"title":"A Meta-Analysis of International Flunixin Pharmacokinetics in Horses: Toward Regulatory Harmonization and Individualized Detection Times Using Bayesian Paradigm","authors":"Taisuke Kuroda, Heather K. Knych, Glenys K. Noble, Yohei Minamijima, Gary Ngai-Wa Leung, Motoi Nomura, Fumiaki Mizobe, Yuhiro Ishikawa, Kanichi Kusano, Pierre-Louis Toutain","doi":"10.1002/dta.3961","DOIUrl":"10.1002/dta.3961","url":null,"abstract":"<p>Flunixin meglumine is widely used to manage pain and inflammation in horses, and its regulation requires robust pharmacokinetic analysis for harmonization. In this study, we conducted a meta-analysis of flunixin disposition using plasma and urine concentration data from 65 horses across four countries to robustly estimate pharmacokinetic parameters in setting screening limits (SLs) for controlling medications in horses. A population (POP) model was developed using nonlinear mixed-effects model analysis. The irrelevant plasma concentration (IPC) and irrelevant urine concentration (IUC) were determined to be 1.9 and 70.2 ng/mL, respectively, with a typical urine-to-plasma ratio (Rss) of 35.9. Using the current International Federation of Horseracing Authorities (IFHA) screening limits (ISLs) (1 ng/mL for plasma; 100 ng/mL for urine), a longer detection time (DT) was observed for plasma than for urine, especially after multiple doses, as plasma ISL corresponds to a slower terminal elimination phase. Increasing the current plasma ISL from 1 to 3 ng/mL—while keeping the current urine ISL at 100 ng/mL—could better align the plasma and urine DTs. As a limitation of this study, both Standardbred and Thoroughbred data were included, and further data collection is needed to fully ascertain potential breed-specific effects. Moreover, this POP model also enabled relatively accurate Bayesian estimation of individual withdrawal times (WTs) from limited data. Clinicians could apply this Bayesian approach to making informed WT recommendations for horses when sufficient data is available. While existing non-POP statistical models remain viable, they may require a more conservative approach to WT estimation than Bayesian methods.</p>","PeriodicalId":160,"journal":{"name":"Drug Testing and Analysis","volume":"18 1","pages":"32-50"},"PeriodicalIF":2.7,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/epdf/10.1002/dta.3961","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145367254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0