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Record W2400243477

Mass spectral analysis of PC-SPES confirms the presence of diethylstilbestrol.

2002· article· en· W2400243477 on OpenAlexaff
Emma S. Tomlinson Guns, S. Larry Goldenberg, Peter de Nully Brown

Bibliographic record

VenuePubMed · 2002
Typearticle
Languageen
FieldMedicine
TopicPhytoestrogen effects and research
Canadian institutionsVancouver General HospitalUniversity of British Columbia
Fundersnot available
KeywordsMedicineDiethylstilbestrolProstate cancerHigh-performance liquid chromatographyProstateExtraction (chemistry)ChromatographyHormoneInternal medicineCancerChemistry
DOInot available

Abstract

fetched live from OpenAlex

INTRODUCTION/OBJECTIVES: PC-SPES is an herbal mixture available over the counter for the treatment of prostate cancer. It was re-called in January 2002 due to alleged contamination with warfarin. Other laboratories, including our own, claim that the potent synthetic estrogen, diethylstilbestrol (DES) which has been used for many years to treat hormone dependent prostate cancer, could be detected in the herbal mixture. Recent clinical studies report objective responses in men with hormone dependent and naïve prostate cancer, and also describe isolated cases of estrogenic side effects. A lack of effective conventional treatments for advanced hormone refractory prostate cancer has led to a widespread use of PC-SPES by patients across the North America continent. The presence of DES in PC-SPES might explain both clinical response and observed side effects in men taking 6-9 capsules per day. METHODS: We tested five batches of commercially available PC-SPES using gas chromatography (GC) and high performance liquid chromatography (HPLC) upon methanolic extraction. Duplicate aliquots were tested for each batch and the results compared to standard curves generated using DES (99% purity). RESULTS AND CONCLUSIONS: We detected significant levels of DES in three out of five tested batches. The presence of a synthetic steroid in PC-SPES is not likely to have occurred as a result of its extraction from a herbal source. The implications of this finding highlight the necessity of regulated quality control and standardization of natural health products.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.001
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: Bench or experimental
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.018
Threshold uncertainty score0.059

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0000.001
Meta-epidemiology (narrow)0.0020.000
Meta-epidemiology (broad)0.0010.001
Bibliometrics0.0030.002
Science and technology studies0.0010.001
Scholarly communication0.0000.001
Open science0.0010.001
Research integrity0.0010.002
Insufficient payload (model declined to judge)0.0180.005

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.

Opus teacher head0.040
GPT teacher head0.269
Teacher spread0.228 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designBench or experimental
Domainnot available
GenreEmpirical

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".

Quick stats

Citations31
Published2002
Admission routes1
Has abstractyes

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