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991.
Vivian Delcourt Patrice Garcia Benjamin Chabot Benoit Loup Pierre Remy Marie‐Agns Popot Ludovic Bailly‐Chouriberry 《Drug testing and analysis》2020,12(6):763-770
Recombinant human erythropoietin (rHuEPO) belongs to the therapeutic class of erythropoiesis stimulating agents (ESAs) due to its implication in the creation pathway of red blood cells and thus enhancement of oxygenation. Because of this bioactivity, rHuEPO has been considered as a major doping agent in sports competitions for decades. Over the years, doping control laboratories designed several analytical strategies applied to human and animal samples to highlight any misuse. Even though multiple analytical approaches have been reported, none has yet been dedicated to racing camels. Here, we describe an analytical strategy to test camel plasma samples at screening using an ELISA assay and a targeted nano‐liquid chromatography–high‐resolution tandem mass spectrometry for confirmatory analysis. The method was validated and has been successfully applied to post‐race samples, allowing the detection of a positive case of rHuEPO administration. 相似文献
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Jia‐Li Wang Kai‐Xin Wang Tian‐Lei Han Jin‐Mei Li Xu He Rui‐Xue Rong Zhi‐Ran Cao Xiao‐Liu Li Ke‐Rang Wang 《Chemical biology & drug design》2020,96(2):870-877
Camptothecin (CPT) and its analogues show potent antitumour activity. However, poor water solubility and severe side effects have restricted their applications in clinical practice. In this paper, a novel self‐assembly based on camptothecin and carbamoylmannose conjugates ( CPT‐Man ) was constructed. The self‐assembly increased the water solubility of camptothecin to 0.64 mg/ml and antitumour activity. Moreover, CPT‐Man could induce obvious cancer cell apoptosis. This work provides a new approach for exploring carbohydrate‐modified antitumour properties by self‐assembled CPT drugs. 相似文献
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Sascha Münster‐Müller Isabelle Matzenbach Thomas Knepper Ralf Zimmermann Michael Pütz 《Drug testing and analysis》2020,12(1):119-126
Vaping of synthetic cannabinoids via e‐cigarettes is growing in popularity. In the present study, we tentatively identified 12 by‐products found in a pure sample of the synthetic cannabinoid Cumyl‐5F‐PINACA (1‐(5‐fluoropentyl)‐N‐(2‐phenylpropan‐2‐yl)‐1H‐indazole‐3‐carboxamide), a prevalent new psychoactive substance (NPS) in e‐liquids, via high‐resolution mass spectrometry fragmentation experiments (HRMS/MS). Furthermore, we developed a procedure to reproducibly extract this synthetic cannabinoid and related by‐products from an e‐liquid matrix via chloroform and water. The extracts were submitted to flash chromatography (F‐LC) to isolate the by‐products from the main component. The chromatographic impurity signature was subsequently assessed by ultra‐high‐performance liquid chromatography coupled to mass spectrometry (UHPLC–MS) and evaluated by automated integration. The complete sample preparation sequence (F‐LC + UHPLC–MS) was validated by comparing the semi‐quantitative signal integrals of the chromatographic impurity signatures of five self‐made e‐liquids with varying concentrations of Cumyl‐5F‐PINACA [0.1, 0.2, 0.5, 0.7 and 1.0% (w/w)], giving an average relative standard deviation of 6.2% for triplicate measurements of preparations of the same concentration and 10.5% between the measurements of the five preparations with different concentrations. Lastly, the chromatographic signatures of 14 e‐liquid samples containing Cumyl‐5F‐PINACA from police seizures and Internet test purchases were evaluated via hierarchical cluster analysis for potential links. For the e‐liquid samples originating from test purchases, it was found that the date of purchase, the identity of the online shop, and the brand name are the critical factors for clustering of samples. 相似文献
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Franziska Gaunitz Tobias Kieliba Mario Thevis Katja Mercer‐Chalmers‐Bender 《Drug testing and analysis》2020,12(1):27-40
This article comprises the development and validation of a protocol for the qualitative analysis of 61 phase I synthetic cannabinoid metabolites in urine originating from 29 synthetic cannabinoids, combining solid‐phase extraction (SPE) utilizing a reversed phase silica‐based sorbent (phenyl) with liquid chromatography–tandem mass spectrometry (LC?MS/MS). Validation was performed according to the guidelines of the German Society of Toxicological and Forensic Chemistry. Sufficient chromatographic separation was achieved within a total runtime of 12.3 minutes. Validation included specificity and selectivity, limit of detection (LOD), recovery and matrix effects, as well as auto‐sampler stability of processed urine samples. LOD ranged between 0.025 ng/mL and 0.5 ng/mL in urine. Recovery ranged between 43% and 97%, with only two analytes exhibiting recoveries below 50%. However, for those two analytes, the LODs were 0.05 ng/mL in urine. In addition, matrix effects between 81% and 185% were determined, whereby matrix effects over 125% were observed for 10 non‐first‐generation synthetic cannabinoid metabolites. The developed method enables the rapid and sensitive detection of synthetic cannabinoid metabolites in urine, complementing the spectrum of existing analytical tools in forensic case work. Finally, application to 61 urine samples from both routine and autopsy case work yielded one urine sample that tested positive for ADB‐PINACA N‐pentanoic acid. 相似文献
997.
Li‐xiang Wu Hui Wang Dan Gou Gang Fu Jing Wang Bian‐qin Guo 《Journal of clinical laboratory analysis》2021,35(1):e23649
ObjectiveTo explore the clinical value of serum IgM and IgG to SARS‐CoV‐2 in COVID‐19.Methods105 COVID‐19 patients were enrolled as the disease group. 197 non‐COVID‐19 patients served as the control group. Magnetic chemiluminescent immunoassay (MCLIA) was used to detect the IgM and IgG.ResultsThe peak of positive rates of SARS‐CoV‐2 IgM was about 1 week earlier than that of IgG. It reached to peak within 15–21 days and then began a slowly decline. The positive rates of IgG were increased with the disease course and reached the peak between 22 and 39 days. The differences in sensitivity of the three detection modes (IgM, IgG, and IgM + IgG) were statistically significant. The largest group of test cases (illness onset 15–21 days) showed that the positive rate of IgG was higher than IgM. Also, the sensitivity of IgM combined with IgG was higher than IgM or IgG. IgM and IgG were monitored dynamically for 16 patients with COVID‐19, the results showed that serological transformation of IgM was carried out simultaneously with IgG in seven patients, which was earlier than IgG in four patients and later than IgG in five patients.ConclusionThe detection of SARS‐CoV‐2 IgM and IgG is very important to determine the course of COVID‐19. Nucleic acid detection combined with serum antibody of SARS‐CoV‐2 may be the best laboratory indicator for the diagnosis of SARS‐CoV‐2 infection and the phrase and predication for prognosis of COVID‐19. 相似文献
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