A simple method is described for the measurement of testosterone (T) and epitestosterone (ET) in human urine samples. The deconjugated steroids were extracted directly from the samples by stir bar sorptive extraction (SBSE) and derivatized in situ on the stir bar by headspace acylation prior to thermal desorption and GC/MS. Extraction and derivatization parameters, namely salt addition, temperature, and time, were optimized to improve the recovery of T and ET by SBSE. The limits of quantification (S/N 10) were 0.9 ng/mL for T and 2.8 ng/mL for ET. Quantification of the steroids in urine samples was performed using standard addition to avoid the influence of matrix effects. The method was applied for the measurement of urinary T and ET in a group of healthy volunteers and HIV+ patients. Decreased levels of T were detected in the HIV+ group, whereas the excretion of ET was comparable for the two groups. Further clinical research is required to elucidate the biomarker significance of the T/ET ratio in HIV infection.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/jssc.200600280 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
LC-HRMS screening procedure for the detection of 11 different classes of prohibited substances in dried urine spots for doping control purposes.
Anal Bioanal Chem
January 2025
Doping Control Laboratory, Department of Diagnostic Sciences, Ghent University, Block B, Ottergemsesteenweg 460, BE-9000, Ghent, Belgium.
Dried urine spots have recently been proposed as an alternative matrix in the anti-doping field. Drying urine may open the opportunity to limit microbial and thermal degradation of the prohibited substances during transportation to the anti-doping laboratories without the need for refrigeration or freezing. In this study, a multi-targeted initial testing procedure was developed for the determination of 237 prohibited drugs/metabolites from 11 different classes in dried urine spots.
View Article and Find Full Text PDFFlow prediction in sound-based uroflowmetry.
Sci Rep
January 2025
Department of Signal Theory and Communications, Universidad de Valladolid, 47002, Valladolid, Spain.
Sound-based uroflowmetry (SU) offers a non-invasive alternative to traditional uroflowmetry (UF) for evaluating lower urinary tract dysfunctions, enabling home-based testing and reducing the need for clinic visits. This study compares SU and UF in estimating urine flow rate and voided volume in 50 male volunteers (aged 18-60), with UF results from a Minze uroflowmeter as the reference standard. Audio signals recorded during voiding were segmented and machine learning algorithms (gradient boosting, random forest, and support vector machine) estimated flow parameters from three devices: Ultramic384k, Mi A1 smartphone, and Oppo smartwatch.
View Article and Find Full Text PDFEvaluation of renal functional reserve with oral protein load or new ultrasound test.
J Nephrol
January 2025
Department of Medicine, Surgery and Neurosciences, Nephrology, Dialysis and Transplantation Unit, University Hospital of Siena, Siena, Italy.
Background: Renal functional reserve (RFR) measures the difference between the stimulated glomerular filtration rate (GFR) and the baseline GFR to detect early signs of renal functional decline. The protein load test (RFR-T) is the gold standard for RFR assessment but is a complicated procedure. Renal intraparenchymal resistance index (RRI) variation test (DRRI-T) is a non-invasive method to measure renal function reserve using ultrasound.
View Article and Find Full Text PDFβ-cyclodextrin polymers as a new sorbent for solid-phase extraction of xenobiotics in Urine.
J Hazard Mater
December 2024
School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China. Electronic address:
This study systematically assessed the performance of a newly developed solid-phase extraction (SPE) material, cellulose-supported aminated β-cyclodextrin polymer (amine-β-CDP@Cellulose), in determining 44 xenobiotics, encompassing endocrine-disrupting chemicals (EDCs), pharmaceuticals, and food additives in urine samples. The primary objective of the research was to synthesize a new sorbent, optimize the extraction protocol, and elucidate the underlying adsorption and desorption mechanisms. Following optimization, it was observed that amine-β-CDP@Cellulose achieved recoveries ranging from 80 % to 120 % for 28 of the 44 targeted xenobiotics, with only three compounds showing recoveries below 50 %.
View Article and Find Full Text PDFBasic Science and Pathogenesis.
Alzheimers Dement
December 2024
The Jackson Laboratory, Bar Harbor, ME, USA.
Background: Late-onset Alzheimer's disease (LOAD) is the leading cause of dementia and a major contributor to increased mortality. Recent human datasets have revealed many LOAD genetic risk factors that are correlated with the degree of AD burden. Further, the complexity and heterogeneity of LOAD appears to be promoted by interactions between genetics and environmental factors such as diet, sedentary behavior, and exposure to toxicants, like lead (Pb), cadmium (Cd), and arsenic (As).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!