Notice bibliographique
Résumé
At some point, we have all sat down to an excellent meal and after devouring as much as we could, no longer had the hankering to eat again for some time. So, what tells our bodies to stop eating? Hormones and chemicals in our brains called neurotransmitters guide the process of feeling full, but how far back in evolution did those processes become established? Vladimiros Thoma and colleagues from Tohoku University, Japan, with collaborators from other universities in Japan, set out to answer this very question by investigating the origins of these chemicals that control appetite in the jellyfish Cladonema pacificum.To identify the genes that regulate feeding in jellyfish, the team investigated which genes are activated or switched off during feeding by comparing famished with recently fed jellyfish. The researchers found that recently fed jellyfish increased the expression of several genes involved in nerve cell activity, leading the scientists to focus on proteins involved in communication between nerve cells. After testing 43 different proteins – a truly Herculean effort – the researchers narrowed the molecules that regulate satiety down to just a few, including one called GLWamide.When the Cladonema jellyfish feed, they ensnare prey such as brine shrimp with their tentacles, pull them back into their bell and ingest the shrimp. To see what part of this feeding ritual GLWamide impacted, the researchers measured how effectively the jellyfish captured their prey and how swiftly their tentacles retracted if the jellyfish were given GLWamide while still hungry. Thoma and colleagues found that hungry jellyfish were not as good at capturing prey when given GLWamide, but they were still better than jellyfish that had just eaten. The hungry animals dosed with GLWamide delayed tentacle contraction when they were fed just like the ones that had already had their fill. This suggests that GLWamide is an appetite suppressor that stops the tentacles from contracting. Next, the team wanted to see where the GLWamide was produced in the jellyfish's body and whether the levels of GLWamide changed based on when the jellyfish were fed. The researchers found that levels of GLWamide in the base of the tentacle increased 3–6 h after feeding, which may be how it suppressed the appetite of the jellyfish.Finally, the team wanted to explore the possibility that GLWamide represents an ancestral signalling system for appetite suppression in all animals. To do this, the researchers looked at a related chemical, called myoinhibitory peptide, in fruit flies. When the hungry jellyfish were given fruit fly myoinhibitory peptide, it reduced the jellyfish's appetite. Additionally, when the researchers gave fruit flies GLWamide, it reduced their appetites as well, showing that GLWamide represents an ancestral signal for appetite suppression. Thoma and colleagues also point out the importance of investigating the function of these chemicals in even more ancient animals than jellyfish, such as single-celled organisms, to discover the true origin of these appetite-suppressing systems. So, the next time you are feeling full after a huge meal, know that your body is working just like it has been programmed to for millions of years.
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 | 0,001 | 0,002 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,001 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,001 | 0,002 |
| Communication savante | 0,002 | 0,002 |
| Science ouverte | 0,000 | 0,002 |
| Intégrité de la recherche | 0,001 | 0,003 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,009 | 0,003 |
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 ».