A multi-target high-throughput liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the detection of low ppt to low ppb levels of anabolic steroids, corticosteroids, anti-diabetics, and non-steroidal anti-inflammatory drugs (NSAIDs) in equine plasma was developed for the purpose of doping control. Plasma samples were first deproteinated by addition of trichloroacetic acid. Drugs were then extracted by solid-phase extraction (SPE) using Bond Elut Certify cartridges, and the extracts were analysed by a triple-quadrupole/linear ion trap LC-MS-MS instrument in positive electrospray ionization (+ESI) mode with selected reaction monitoring (SRM) scan function. Chromatographic separation of the targeted drugs was achieved using a reverse phase 3.3 cm L x 2.1 mm ID, 3 microm particle size LC column with gradient elution. Plasma samples fortified with 66 targeted drugs including betamethasone, boldione, capsaicin, flunisolide, gestrinone, gliclazide, 17alpha-hydroxyprogesterone hexanoate, isoflupredone and triamcinolone acetonide, etc. at low ppt to low ppb levels could be consistently detected. No significant matrix interference was observed at the retention time of the targeted ion transitions when blank plasma samples were analysed. The method has been validated for its extraction recoveries, precision and sensitivity, and is used regularly in the authors' laboratory to screen for the presence of these drugs in plasma samples from racehorses.
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http://dx.doi.org/10.1016/j.chroma.2007.11.022 | DOI Listing |
Adv Healthc Mater
January 2025
Beijing Key Laboratory of Preclinical Research and Evaluation for Cardiovascular Implant Materials, Animal Experimental Centre, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, China.
Myocarditis, a leading cause of sudden cardiac death and heart transplantation, poses significant treatment challenges. The study of clinical samples from myocarditis patients reveals a correlation between the pathogenesis of myocarditis and cardiomyocyte mitochondrial DNA (mtDNA). During inflammation, the concentration of mtDNA in cardiomyocytes increases.
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January 2025
School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Developing high-performance alloys is essential for applications in advanced electromagnetic energy conversion devices. In this study, we assess Fe-Co-Ni alloy compositions identified in our previous work through a machine learning (ML) framework, which used both multi-property ML models and multi-objective Bayesian optimization to design compositions with predicted high values of saturation magnetization, Curie temperature, and Vickers hardness. Experimental validation was conducted on two promising compositions synthesized using three different methods: arc melting, ball milling followed by spark plasma sintering (SPS), and chemical synthesis followed by SPS.
View Article and Find Full Text PDFHeliyon
January 2025
School of Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan.
Bevacizumab is widely used in various clinical indications, but investigations into its optimal dosage for treating CNS metastases remain limited. The BEEP regimen, comprising bevacizumab, etoposide, and cisplatin, has recently demonstrated promising clinical outcomes for patients with breast cancer brain metastasis (BCBM) or leptomeningeal metastasis (LM). This study aimed to evaluate the exposure-response relationship of bevacizumab in BCBM patients and to explore the improved CNS penetration of chemotherapy by bevacizumab with LM patients.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Pediatric Neurology, University of Health Sciences, Gülhane Training and Research Hospital, Ankara, the Republic of Türkiye.
Objective: Epilepsy is one of the most common neurological diseases in the pediatric population. Orexins are excitatory peptides and associated with energy homeostasis, eating and drinking behaviors, sleep regulation, sleep-wake periods, analgesia, and cognitive activities such as attention, learning, and memory. The aim of this study was to reveal the relationship between plasma orexin levels and seizures in pediatric epilepsy patients with seizures, epilepsy patients in remission, and healthy control group with similar demographic characteristics.
View Article and Find Full Text PDFEJIFCC
December 2024
Department of Laboratory Medicine, National University Hospital, Singapore.
Background: Serum (plasma) creatinine and cystatin C are widely used in pediatric clinical practice to assess glomerular filtration rate. Both markers have limitations due to the low index of individuality, which affects the clinical sensitivity of population-based reference intervals, especially when wide age ranges are considered. This study aimed to establish age-related reference intervals for plasma cystatin C and creatinine in Vietnamese children.
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