Factors affecting urinary excretion of testosterone metabolites conjugated with cysteine
Bibliographic record
Abstract
The implementation of the athlete steroidal passport in doping control analysis aims to detect intra-individual changes in the steroid profile related to the abuse of anabolic steroids. In this context, the study of intrinsic variations associated with each marker is of utmost importance. In the present work, the influence of several factors in the excretion of the recently reported testosterone metabolites conjugated with cysteine (Δ(1) -AED; 1,4-androstadien-3,17-dione, Δ(6) -AED; 4,6-androstadien-3,17-dione, Δ(6) -T; 4,6-androstadien-17β-ol-3-one, and Δ(15) -AD; 15-androsten-3,17-dione) is evaluated for the first time. Degradation experiments at 37 °C proved that, although the cysteinyl moiety is released, the variation for urinary Δ(1) -AED/Δ(6) -AED, Δ(1) -AED/Δ(6) -T ratios is less than 30%. Moreover, freeze/thaw cycle testing resulted in RSDs values below 15% for all the analytes. Regarding infradian variability, moderate variations (below 40%) were observed. Additionally, notable alterations in the excretion of these compounds have been observed in the earliest stages of pregnancy. UGT2B17 polymorphism, responsible for the low T/E ratio found in some population, does not influence the excretion of cysteinyl compounds whereas the intake of exogenous substances (alcohol or 5α-reductase inhibitors) dramatically affects their excretion. The urinary concentrations of Δ(1) -AED, Δ(6) -AED, and Δ(15) -AD decreased (<50 %) after the ethanol intake, whereas after the administration of dutasteride, an important increase was observed for the concentrations of Δ(6) -AED, Δ(6) -T and Δ(15) -AD. Overall, the presented data describes the stability of the urinary cysteinyl steroids under the influence of many factors, proving their potential as suitable parameters to be included in the steroidal module of the athlete's biological passport.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".