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Study question Does NAT10-mediated N4-acetylcytidine (ac4C) in RNA, a newly identified mRNA epigenetic modification, participate in modulating in vitro maturation(IVM) of oocytes? Summary answer NAT10-mediated ac4C modification is an important regulatory factor during oocyte maturation in vitro, by regulating genes associated with translation, mitochondrial functions and protein destabilization. What is known already Unlike somatic cells, transcription and translation are uncoupled during oocyte maturation and gene expression is mainly regulated by post-transcriptional modulation, including mRNA degradation, translation and posttranslational modification, which are complex and have not been fully investigated. RNA ac4C is a newly identified mRNA modification and a key determinant of post-transcriptional regulation, which has been shown to promote mRNA stability and translation, and NAT10 is the only known RNA acetyltransferase. Therefore, NAT10-mediated ac4C represents a possible epigenetic regulator in oocyte maturation. Study design, size, duration Oocytes at different stages from mice were collected to detect the changing levels of ac4C and NAT10 during maturation. NAT10 in GV-stage oocytes was knocked down before IVM, to confirm the regulatory role of NAT10-mediated ac4C in meiotic process, followed by further exploration of cellular mechanisms. Each experiment was repeated at least three times, and data were analyzed by chi-square test, one-way ANOVA or unpaired-sample t-test. Participants/materials, setting, methods The expression of ac4C and NAT10 was detected by immunohistochemistry. NAT10 was knocked down in GV-stage oocytes by RNA interference through electroporation. The efficacy of knockdown was confirmed by qPCR and immunohistochemistry targeting ac4C and NAT10, and the percentages of oocytes maturated in vitro were compared among groups. High-throughput sequencing and RNA immunoprecipitation were performed to reveal the modulated genes. Proteins specifically binding to ac4C sites were identified by RNA pulldown and mass spectrometry. Main results and the role of chance We first retrieved publicly available data from GEO and found that transcripts with potential ac4C sites were enriched in genes downregulated during IVM (P Limitations, reasons for caution This study was performed in vitro. The role of NAT10-mediated ac4C in vivo remains to be elucidated. Also, limited by current techniques, ac4C modification in oocytes cannot be detected. Our exploration of regulated genes and ac4C binding proteins were performed in somatic cell lines. Wider implications of the findings: Post-transcriptional modulation is crucial in oocyte maturation. Our study using in-vitro systems for mouse oocyte identified NAT10-mediated ac4C as an important regulator in IVM. It provided a new insight into the epigenetic mechanisms of IVM, which may lead to improvement of clinical IVM systems. Trial registration number Not applicable

Study question Does NAT10-mediated N4-acetylcytidine (ac4C) in RNA, a newly identified mRNA epigenetic modification, participate in modulating in vitro maturation(IVM) of oocytes? Summary answer NAT10-mediated ac4C modification is an important regulatory factor during oocyte maturation in vitro, by regulating genes associated with translation, mitochondrial functions and protein destabilization. What is known already Unlike somatic cells, transcription and translation are uncoupled during oocyte maturation and gene expression is mainly regulated by post-transcriptional modulation, including mRNA degradation, translation and posttranslational modification, which are complex and have not been fully investigated. RNA ac4C is a newly identified mRNA modification and a key determinant of post-transcriptional regulation, which has been shown to promote mRNA stability and translation, and NAT10 is the only known RNA acetyltransferase. Therefore, NAT10-mediated ac4C represents a possible epigenetic regulator in oocyte maturation. Study design, size, duration Oocytes at different stages from mice were collected to detect the changing levels of ac4C and NAT10 during maturation. NAT10 in GV-stage oocytes was knocked down before IVM, to confirm the regulatory role of NAT10-mediated ac4C in meiotic process, followed by further exploration of cellular mechanisms. Each experiment was repeated at least three times, and data were analyzed by chi-square test, one-way ANOVA or unpaired-sample t-test. Participants/materials, setting, methods The expression of ac4C and NAT10 was detected by immunohistochemistry. NAT10 was knocked down in GV-stage oocytes by RNA interference through electroporation. The efficacy of knockdown was confirmed by qPCR and immunohistochemistry targeting ac4C and NAT10, and the percentages of oocytes maturated in vitro were compared among groups. High-throughput sequencing and RNA immunoprecipitation were performed to reveal the modulated genes. Proteins specifically binding to ac4C sites were identified by RNA pulldown and mass spectrometry. Main results and the role of chance We first retrieved publicly available data from GEO and found that transcripts with potential ac4C sites were enriched in genes downregulated during IVM (P Limitations, reasons for caution This study was performed in vitro. The role of NAT10-mediated ac4C in vivo remains to be elucidated. Also, limited by current techniques, ac4C modification in oocytes cannot be detected. Our exploration of regulated genes and ac4C binding proteins were performed in somatic cell lines. Wider implications of the findings Post-transcriptional modulation is crucial in oocyte maturation. Our study using in-vitro systems for mouse oocyte identified NAT10-mediated ac4C as an important regulator in IVM. It provided a new insight into the epigenetic mechanisms of IVM, which may lead to improvement of clinical IVM systems. Trial registration number not applicable

Cardiovascular disease (CVD) is the number one cause of death in humans. Arrhythmia induced by gene mutations, heart disease, or hERG K+ channel inhibitors is a serious CVD that can lead to sudden death or heart failure. Conventional cardiomyocyte-based biosensors can record extracellular potentials and mechanical beating signals. However, parameter extraction and examination by the naked eye are the traditional methods for analyzing arrhythmic beats, and it is difficult to achieve automated and efficient arrhythmic recognition with these methods. In this work, we developed a unique automated template matching (ATM) cardiomyocyte beating model to achieve arrhythmic recognition at the single beat level with an interdigitated electrode impedance detection system. The ATM model was established based on a rhythmic template with a data length that was dynamically adjusted to match the data length of the target beat by spline interpolation. The performance of the ATM model under long-term astemizole, droperidol, and sertindole treatment at different doses was determined. The results indicated that the ATM model based on a random rhythmic template of a signal segment obtained after astemizole treatment presented a higher recognition accuracy (100% for astemizole treatment and 99.14% for droperidol and sertindole treatment) than the ATM model based on arrhythmic multitemplates. We believe this highly specific ATM method based on a cardiomyocyte beating model has the potential to be used for arrhythmia screening in the fields of cardiology and pharmacology.

Electroporation serves as a powerful technique to introduce the exogenous nucleotides, DNA, RNA, proteins, dyes, and virus particles into cells. Through the effect of high intensity of electric field, the permeability of the cell membrane is instantaneously improved to absorb the exogenous molecules in surrounding medium. To protect the cell viability, ultralow-voltage electroporation techniques are well developed by versatile devices, and delivery efficiency is commonly assessed by label-based analysis by microscope-ImageJ or flow cytometry. However, accuracy and complexity of these analytical strategies still hinder efficient and precise biomedical studies in situ. Here we developed an intracellular delivery biosensing system by nanostrawed electroporation array (NEA) that can efficiently assess the universal electroporation performance by cell viability, delivery efficiency, and cell mortality. The intracellular delivery biosensing system consists of NEA, fluorescent microscope, and automated analysis software. Intracellular delivery biosensing system of electroporation quality is based on the enhanced fluorescent watershed segmentation (enhanced FWS) algorithm, which possessed low deviation (~5%) and significantly shortened the operation time (~8 s/10 images) in contrast to high deviation (~13%) and long operation time (~10 min/10 images) of conventional inaccurate, labor-intensive and time-consuming methods. It is believed that the intracellular delivery biosensing system will be a promising universal platform to assess nanodevice electroporation in the fields of cell biology, biotechnology, and medicine.

Uterine fibroids are common benign tumors in the female reproductive system. A hysterectomy is the most effective treatment for symptomatic fibroids. For patients desiring pregnancy, laparoscopic intracapsular myomectomy (LM) is an alternative surgery option. Although LM is widely accepted to treat fibroids, it is technically demanding with risk of excessive bleeding and difficult suturing, especially in cases with large fibroids or tumors in unusual locations. Therefore, we developed an intracapsular rotary-cut procedure (IRCP) as a modification of laparoscopic intracapsular myomectomy, with the intention to minimize risks of LM and help uterine healing. A summary of the improvements to the IRCP is described: 1) making an incision at the site of the fibroid with a length of one-third to one-half of the fibroid's diameter at a depth reaching the fibroid's surface; 2) holding the fibroid stably and making rotary cuts on the fibroid at a depth of 0.5-1 cm within its pseudo-capsule while pulling it outward slightly, making sure not to cut off any pieces of the fibroid; and 3) repeating the cutting-and-pulling until the longest dimension of the fibroid is outside the incision. The multiple cuts are to minimize the diameter and extend the length of the fibroid. When the multiple cuts cause half of the fibroid body to "shrink", the fibroid is squeezed out by contraction of the surrounding myometrium. Evaluation of the outcomes of IRCP showed that the time of enucleation and suturing, intraoperative bleeding, and decline of hemoglobin were significantly lower in the IRCP group than the LM group. As for reproductive outcomes, the full-term live birth rate of the IRCP group was significantly higher than that of LM group. However, there was no difference in delivery modes between the two groups. In conclusion, IRCP significantly benefits fertility preservation by minimizing damage to the uterus, protecting myofibers of the pseudo-capsule, and resulting in a shallower residual cavity, which eases stitching and causes less bleeding. It is worthwhile to adopt IRCP in younger patients who desire preservation of their fertility.