In this study, the direct analysis of doping agents in urine samples with no sample preparation by a modified paper spray mass spectrometry (PS-MS) methodology has been demonstrated for the first time. We have described a paper surface treatment with trichloromethylsilane using a gas-phase reaction to increase the ionization of target compounds. This approach was applied for the analysis of two classes of banned substances in urine samples: anabolic agents (trenbolone and clenbuterol) and diuretics (furosemide and hydrochlorothiazide). Under optimized conditions, the developed methods presented satisfactory repeatability, and an analysis of variance showed linearity without lack-of-fit. Highly sensitive detections as low as sub-nanogram per milliliter levels, which is below the minimum required performance levels proposed by the World Anti-Doping Agency, have been reached using the hydrophobic PS-MS analysis without any preconcentration and cleanup step.
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http://dx.doi.org/10.1021/jasms.0c00063 | DOI Listing |
Chaos
January 2025
School of Mathematics and Statistics, University College Dublin, Dublin 4 D04 V1W8, Ireland.
Synaptic plasticity plays a fundamental role in neuronal dynamics, governing how connections between neurons evolve in response to experience. In this study, we extend a network model of θ-neuron oscillators to include a realistic form of adaptive plasticity. In place of the less tractable spike-timing-dependent plasticity, we employ recently validated phase-difference-dependent plasticity rules, which adjust coupling strengths based on the relative phases of θ-neuron oscillators.
View Article and Find Full Text PDFIssues Ment Health Nurs
January 2025
Department of Psychiatry, Ryhov County Hospital, Jönköping, Sweden.
Patient-Initiated Brief Admission (PIBA) is perceived as a constructive intervention. It remains uncertain whether PIBA contributes to healthier behaviors among its users. To comprehend patients' motivation to engage in health-promoting behaviors, it is essential to understand how various nursing interventions influence the behavior-specific thoughts and feelings that lead to healthy behaviors.
View Article and Find Full Text PDFChondrosarcomas are the second most common primary bone sarcoma. Due to chondrosarcomas relative resistance to chemotherapy and radiation, surgical treatment has become the mainstay treatment option. The purpose of our study was to understand the proportion of patients in this population who undergo non-operative treatment options secondary to various reasons and analyze the difference in survival as well as patient and cancer specific characteristics between the two groups.
View Article and Find Full Text PDFBlood
January 2025
University of Chicago, Chicago, Illinois, United States.
Most diffuse large B-cell lymphoma (DLBCL) patients treated with immunotherapies such as bispecific antibodies (BsAb) or chimeric antigen receptor (CAR) T cells fail to achieve durable treatment responses, underscoring the need for a deeper understanding of mechanisms that regulate the immune environment and response to treatment. Here, an integrative, multi-omic approach was applied to multiple large independent datasets in order to characterize DLBCL immune environments, and to define their association with tumor cell-intrinsic genomic alterations and outcomes to CD19-directed CAR T-cell and CD20 x CD3 BsAb therapies. This approach effectively segregated DLBCLs into four immune quadrants (IQ) defined by cell-of-origin and immune-related gene set expression scores.
View Article and Find Full Text PDFJ Am Soc Mass Spectrom
January 2025
Department of Chemistry, Center for Innovative Technology, Vanderbilt University, Nashville, Tennessee 37235, United States.
Desorption electrospray ionization mass spectrometry imaging (DESI-MSI) provides direct analytical readouts of small molecules that can be used to characterize the metabolic phenotypes of genetically engineered bacteria. In an effort to accelerate the time frame associated with the screening of mutant libraries, we have developed a high-throughput DESI-MSI analytical workflow implementing a single raster line-scan strategy that facilitates the collection of location-resolved molecular information from engineered strains on a subminute time scale. Evaluation of this "Fast-Pass" DESI-MSI phenotyping workflow on analytical standards demonstrated the capability of acquiring full metabolic profiling information with a throughput of ∼40 s per sample.
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