Natural stable isotopes: new tracers in environmental health studies
Notice bibliographique
Résumé
An important objective of modern environmental sciences is to elucidate the relationship between environmental pollution and human health. The development of adverse health effects is heavily influenced by extrinsic environmental factors. There is evidence that environmental factors may contribute >70%–90% to the development of most common cancer types, while only ∼10%–30% are attributed to unavoidable intrinsic risks (e.g. random errors in DNA replication) [1]. However, research into environmental health is limited by a lack of proper analytical tools. It is still extremely difficult to screen health risks and trace the sources of pollutants in complex systems by conventional analytical methods that mainly rely on the concentration analysis of environmental samples. The analysis of stable isotope ratios (beyond conventional elements such as C, H, O, N, S) can provide powerful tracers and chronometers for geosciences, archaeology, anthropology and environmental studies [2]. In the past decade, their application in health research has also been explored, but at a relatively slow rate. The isotopic composition of several biologically relevant elements (e.g. Fe, Ca, Cu, S) in the human body has been examined. For example, the Fe isotopic composition of blood was found to differ between individuals and sexes [3] and the Fe in blood of hereditary hemochromatosis patients was isotopically heavier than that of healthy individuals due to isotope-sensitive intestinal Fe absorption [4]. Another study found that the natural stable isotope composition of Ca in urine responded rapidly to changes in bone mineral balance [5]. The onset of bone loss could be detected by monitoring changes in Ca isotope ratios in one week—much quicker than that using desitometry, which often requires wait times in the order of months or years. Thus, the analysis of Ca isotope ratios may provide a more promising approach for early diagnosis and therapy for metabolic bone diseases. A recent paper studied natural Cu and S isotope ratio variations in the blood of hepatocellular carcinoma (HCC) patients [6]. The hypoxic tumor microenvironment may affect the metabolism and the redox state of some bioessential elements, such as Cu and S, consequently resulting in stable isotope fractionation. With regard to liver cancer, the liver is the main Cu reservoir in the human body and a pivotal organ for the metabolism of S-containing amino acids. In the blood of HCC patients, the Cu level was higher than that in control subjects, and Cu and S were enriched in light isotopes (63Cu enriched by ∼0.4‰ and 32S enriched by ∼1.5‰) compared with the control subjects. Notably, the isotopic signatures indicated that the extra Cu burden in the blood of HCC patients was not due to exogenous Cu uptake (dietary origin), but rather reflected the massive reallocation and subsequent immobilization of Cu within cysteine-rich proteins, such as metallothioneins [6]. Therefore, stable isotopes may not only be employed as new biomarkers for cancer diagnosis, but also provide extra information in pathological studies by enabling tracing of elements. Inspired by those early reports, we believe that stable isotope ratio measurements are potentially powerful tools in different branches of environmental health science. They may be used as fast-responding biomarkers in environmental epidemiological studies and provide extra concentration-independent information reflecting the biological processes (e.g. redox reaction, metal-protein binding) on toxicological mechanisms and health risks in exposure studies. Further studies are also encouraged to expand the application to additional elements, including environmental contaminants (e.g. Hg, Pb, Cr), to directly link extrinsic environmental factors with diseases.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,013 | 0,013 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,002 | 0,001 |
| Bibliométrie | 0,005 | 0,008 |
| Études des sciences et des technologies | 0,001 | 0,004 |
| Communication savante | 0,003 | 0,006 |
| Science ouverte | 0,002 | 0,002 |
| Intégrité de la recherche | 0,004 | 0,004 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,003 | 0,002 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».