Endometrial Gene and Protein Expressions in Dairy Cows and Heifers.
Notice bibliographique
Résumé
The pregnancy rate is a key parameter that reflects the reproductive efficiency of a dairy cow. Pregnancy rates of high producing, lactating dairy cows have declined drastically over the past several decades and this could be due to changes in the quality of embryonic, uterine and nutritional environments. However, pregnancy rates of heifers have not declined over the same period. Lower pregnancy rates in cows have resulted in increased calving interval and decreased amount of milk production which results in a considerable loss to the dairy industry. Conceptus growth and development are controlled to some extent by the maternal uterine environment. Therefore, the health of the uterus is important for the embryonic survival and maintenance of pregnancy. A number of factors play essential roles in modulating the differentiative and proliferative changes in the endometrium during the period of early embryonic development, including steroid hormones, growth factors, and cytokines. In order to understand the reasons for reduced pregnancy rates in dairy cows, the expression levels of tumor necrosis factor-α (TNFα), interleukin-1 (IL1), insulin like growth factor 1 (IGF1), fibroblast growth factor 2 (FGF2), uterine milk protein (UTMP), apoptotic proteins (BAX and BCL2) and heat shock protein 70 (HSP70) were studied in uterine endometrium of cows and heifers. Preliminary study was performed to optimize the PCR conditions for the above genes using uteri collected from the local abattoir. Heifers and parous cows (n=5, each) were estrus synchronized by administering 25 mg PGF2α (Lutalyse) twice intramuscularly 12 days apart. Two endometrial biopsies were performed 12 days after estrus (during the mid luteal phase), and the collected tissue samples were snap frozen in liquid nitrogen and stored at -80°C or saved in 3% formaldehyde until processing. RNA was extracted using Tri Reagent and the quantity and quality of were assessed by measuring the optical densities using Nanodrop ND-1000 spectrophotometer. After reverse transcription of total RNA (Cells-to cDNA II kit, Ambion), PCR was performed using JumpStart RED Taq Ready Mix PCR reaction mix and gene specific primers. PCR products were analysed by gel electrophoresis using ethidium bromide (0.2µg/ml) stained 2% agarose gel and photographed under ultraviolet illumination. The optical density of each gene was measured by Scion 4.02 software and normalized to house keeping gene (G3PDH). To quantify the protein levels of IL1, TNFα and FGF2, immunohistochemistry of paraffin embedded sections was performed using polyclonal antibodies. The expression level was quantified using HSCORE method. Transcript abundance for BCL2, IL1, TNFα, FGF2 and UTMP were significantly higher in heifers compared to cows. Immunohistochemistry revealed an increased expression of IL1, TNFα and FGF2 proteins in the endometrium of heifers than cows. In conclusion, the differential expression of above genes may have an effect on the quality of the endometrium and this in turn explains the differences in pregnancy rates observed in dairy cows and heifers. (poster)
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 | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
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 ».