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Study questionCan the histone deacetylase inhibitor Scriptaid improve the efficiency of the development of round spermatid injection (ROSI)-fertilized embryos in a mouse model?Summary answerTreatment of ROSI mouse zygotes with Scriptaid increased the expression levels of several development-related genes at the blastocyst stage, resulting in more efficient in vitro development of the blastocyst and an increased birth rate of ROSI-derived embryos.What is known alreadyThe full-term development of embryos derived through ROSI is significantly lower than that following ICSI in humans and other species.Study design, size, durationOocytes, spermatozoa and round spermatids were collected from BDF1 (C57BL/6 × DBA/2) mice. For in vitro development experiments, mouse ROSI-derived zygotes were treated with Scriptaid at different concentrations (0, 125, 250, 500 and 1000 nM) and for different exposure times (0, 6, 10, 16 or 24 h). Next, blastocysts of the optimal Scriptaid-treated group and the non-treated ROSI group were separately transferred into surrogate ICR mice to compare in vivo development with the ICSI group (control). Each experiment was repeated at least three times.Participants/materials, setting, methodsMetaphase II (MII) oocytes, spermatozoa and round spermatids were obtained from sexually mature BDF1 female or male mice. The developmental potential of embryos among the three groups (the ICSI, ROSI and optimal Scriptaid-treated ROSI groups) was assessed based on the rates of obtaining zygotes, two-cell stage embryos, four-cell stage embryos, blastocysts and full-term offspring. In addition, the expression levels of development-related genes (Oct4, Nanog, Klf4 and Sox2) were analysed using real-time PCR, and the methylation states of imprinted genes (H19 and Snrpn) in these three groups were detected using methylation-specific PCR (MS-PCR) sequencing following bisulfite treatment.Main results and the role of chanceThe in vitro experiments revealed that treating ROSI-derived zygotes with 250 nM Scriptaid for 10 h significantly improved the blastocyst formation rate (59%) compared with the non-treated group (38%) and further increased the birth rates of ROSI-derived embryos from 21% to 40% in vivo. Moreover, in ROSI-derived embryos, the expression of the Oct4, Nanog and Sox2 genes at the blastocyst stage was decreased, but the optimal Scriptaid treatment restored expression to a level similar to their ICSI counterparts. In addition, Scriptaid treatment moderately repaired the abnormal DNA methylation pattern in the imprinting control regions (ICRs) of H19 and Snrpn.Large scale dataN/A LIMITATIONS, REASONS FOR CAUTION: Because of the ethics regarding the use of human gametes for ROSI studies, the mouse model was used as an approach to explore the effects of Scriptaid on the developmental potential of ROSI-derived embryos. However, to determine whether these findings can be applied to humans, further investigation will be required.Wider implications of the findingsScriptaid treatment provides a new means of improving the efficiency and safety of clinical human ROSI.Study funding/competing interestsThe study was financially supported through grants from the National Key Research Program of China (No. 2016YFC1304800); the National Natural Science Foundation of China (Nos: 81170756, 81571486); the Natural Science Foundation of Shanghai (Nos: 15140901700, 15ZR1424900) and the Programme for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning. There are no conflicts of interest to declare.

Recycling construction waste while reducing natural sand mining has proven to be a sustainable option for environmental protection. Multiwalled Carbon nanotubes (MWCNTs) have the potential to enhance the mechanical characteristics of recycled fine aggregates (RFA) mortars. This research aims to explore the feasibility of applying MWCNTs in the RFA mortars. Various concentrations of MWCNTs were added to different grades of RFA-prepared mortar to obtain an optimal concentration. Besides, the scanning electron microscopy (SEM) analysis was conducted to observe the microstructure inside the RFA-prepared mortar. The nuclear magnetic resonance (NMR) test was used to test the pore structure of mortars. The results show that the RFA quality is relevant to the initial compressive strength of the RFA resource. The optimal concentration and the enhancement effect of MWCNTs on the three different RFA-prepared mortars are obtained with mechanical properties proven. The SEM images show that more cracks exist in the RFA-prepared mortars, and the NMR test shows that the number of pores inside the RFA-prepared mortars is significantly larger than that in the natural sand mortar. Nevertheless, an appropriate amount of MWCNTs can create a dense network and great bond inside the mortar, improving its mechanical properties. [ABSTRACT FROM AUTHOR]