Objective To investigate the effect of luteinising hormone(LH)level on the day of gonadotropin releasing hormone(GnRH)antagonist administration upon the outcomes of pregnancy and embryo quality during in vitro fertilization-embryo transfer(IVF-ET)assisted conception.Methods The data of female infertility patients who received routine IVF-ET treatment with antagonist regimen and expected to have normal ovarian response at the Reproductive Medicine Center,Zhongnan Hospital of Wuhan University,from January 2018 to December 2022 were retrospectively analyzed,and the patients were grouped according to their LH levels on the day of GnRH antagonist administration,the clinical pregnancy rate,implantation rate,egg maturity,fertilization rate,cleavage rate,2 Prokaryotic embryo ratio,D3 high quality embryo rate and blastocyst formation rate between the groups were compared,and the receiver operating characteristic(ROC)curves were plotted to evaluate the predictive value of the LH levels for the clinical pregnancies.Results A total of 188 patients were included in the study,and the median LH level on the day of GnRH antagonist administration was 3.79(2.48,6.14)mIU/mL.The clinical pregnancy rate and implantation rate of fresh embryo transfer were the lowest when LH＜2.48 mIU/mL(P＜0.05),while the clinical pregnancy rate and implantation rate were the highest when LH＞6.14 mIU/mL,and the difference was statistically significant(P＜0.01),but there was no statistical difference in gamete and embryonic development parameters between the groups(P＞0.05).The area under the ROC curve was 0.678,which means LH level has a certain degree of accuracy in predicting clinical pregnancy.Conclusion The use of antagonists with LH levels higher than 6.14 mIU/mL during controlled ovarian hyperstimulation led to the best clinical pregnancy outcome.

Ribosomal engineering is a technique that can improve the biosynthesis of secondary metabolites in the antibiotics-resistant mutants by attacking the bacterial RNA polymerase or ribosome units using the corresponding antibiotics. Ribosomal engineering can be used to discover and increase the production of valuable bioactive secondary metabolites from almost all actinomycetes strains regardless of their genetic accessibility. As a consequence, ribosomal engineering has been widely applied to genome mining and production optimization of secondary metabolites in actinomycetes. To date, more than a dozen of new molecules were discovered and production of approximately 30 secondary metabolites were enhanced using actinomycetes mutant strains generated by ribosomal engineering. This review summarized the mechanism, development, and protocol of ribosomal engineering, highlighting the application of ribosomal engineering in actinomycetes, with the aim to facilitate future development of ribosomal engineering and discovery of actinomycetes secondary metabolites.
Actinobacteria/metabolism* ; Actinomyces/genetics* ; Anti-Bacterial Agents/metabolism* ; Multigene Family ; Ribosomes/genetics*