Alternative splicing (AS) as one of the important post-transcriptional regulatory mechanisms has been poorly studied during embryogenesis. In this study, we comprehensively collected and analyzed the transcriptome data of early embryos from human and mouse. We found that AS plays an important role in this process and predicted candidate RNA binding protein (RBP) regulators that are associated with reproductive development. The predicted RBPs such as EIF4A3, MAK16, SRSF2, and UTP23 were found to be associated with reproductive disorders. By Smart-seq2 sequencing analysis, we identified 5445 aberrant alternative splicing events in Eif4a3-knockdown embryos. These events were preferentially associated with RNA processing. In conclusion, our work on the landscape and potential function of alternative splicing events will boost further investigation of detailed mechanisms and key factors regulating mammalian early embryo development and promote the inspiration of pharmaceutical approaches for disorders in this crucial biology process.

The left-right symmetry breaking of vertebrate embryos requires nodal flow. However, the molecular mechanisms that mediate the asymmetric gene expression regulation under nodal flow remain elusive. Here, we report that heat shock factor 1 (HSF1) is asymmetrically activated in the Kupffer\'s vesicle of zebrafish embryos in the presence of nodal flow. Deficiency in HSF1 expression caused a significant situs inversus and disrupted gene expression asymmetry of nodal signaling proteins in zebrafish embryos. Further studies demonstrated that HSF1 is a mechanosensitive protein. The mechanical sensation ability of HSF1 is conserved in a variety of mechanical stimuli in different cell types. Moreover, cilia and Ca2+-Akt signaling axis are essential for the activation of HSF1 under mechanical stress in vitro and in vivo. Considering the conserved expression of HSF1 in organisms, these findings unveil a fundamental mechanism of gene expression regulation by mechanical clues during embryonic development and other physiological and pathological transformations.

The role of SET domain containing 7 (SETD7) during human hematopoietic development remains elusive. Here, we found that deletion of SETD7 attenuated the generation of hematopoietic progenitor cells (HPCs) during the induction of hematopoietic differentiation from human embryonic stem cells (hESCs). Further analysis specified that SETD7 was required for lateral plate mesoderm (LPM) specification but dispensable for the generation of endothelial progenitor cells (EPCs) and HPCs. Mechanistically, rather than depending on its histone methyltransferase activity, SETD7 interacted with β-catenin at lysine residue 180 facilitated its degradation. Diminished SETD7 expression led to the accumulation of β-catenin and the consequent activation of the Wnt signaling pathway, which altered LPM patterning and facilitated the production of paraxial mesoderm (PM). Taken together, the findings indicate that SETD7 is related to LPM and PM patterning via posttranslational regulation of the Wnt/β-catenin signaling pathway, providing novel insights into mesoderm specification during hematopoietic differentiation from hESCs.

Ectopic thyroid tissue is a rare condition manifested as the appearance of thyroid tissue outside the thyroid gland. Here, we report a case of ectopic thyroid tissue in the breast. A 48-year-old Chinese woman who was diagnosed with breast cancer received modified radical mastectomy. A thyroid tissue was found on subsequent pathological examination. The ectopic thyroid tissue was confirmed by immunohistochemistry staining of thyroid biomarkers, including thyroglobulin, thyroid transcription factor-1, and thyroid peroxidase. Currently, abnormal thyroid anlage descent is the main theory to explain ectopic thyroid tissue, especially lingual thyroid. However, it is far-fetched to explain the pathogenesis of ectopic thyroid tissues existed in organs or tissues far from thyroid such as iris, cardiac, pulmonary, duodenal, adrenal, and vertebral. Here, we reviewed the previous cases of ectopic thyroid tissue in breast and proposed a \"entoderm migration\" theory to explain distant ectopic thyroid tissues based on embryonic development perspective.

Urogenital sinus (UGS) malformation, also known as persistent urogenital sinus (PUGS), is a rare congenital malformation of the urogenital system. It arises when the urethra and vaginal opening fail to form properly in the vulva and fuse incorrectly. PUGS can occur as an isolated abnormality or as part of a complex syndrome, and is frequently associated with congenital adrenal hyperplasia (CAH). The management of PUGS is not well-established, and there are no standardized guidelines on when to perform surgery or how to follow up with patients over the long term. In this review, we discuss the embryonic development, clinical evaluation, diagnosis, and management of PUGS. We also review case reports and research findings to explore best practices for surgery and follow-up care, in hopes of increasing awareness of PUGS and improving patient outcomes.

Characterization of molecular mechanisms underlying pregnancy development of sows is important for the genetic improvement of pig breeding traits, and also provides resources for biomedical research on human pregnancy diseases. However, the transcriptome and metabolome across multiple developmental stages of sow pregnancy were still lacking. In this study, we obtained 84 distinct RNA sequencing and 42 metabolome datasets of pig blood across six development stages from estrus to lactation. We confirmed the initial sequence and exonic structural features, stage-specific molecules, expression or accumulation pattern of molecules, the regulatory mechanism of transcriptome and metabolome, and important pregnancy-related metabolites both in pigs and humans. In conclusion, we proposed the key differences among the stages of sows from estrus to lactation in RNAs and metabolites and put forward key markers. These data results were expected to provide essential resources for pig breeding and biomedical research on human pregnancy disease.

BACKGROUND: Students\' engagement with learning materials and discussions with teachers and peers before and after lectures are among the keys to the successful implementation of blended programs. Mixed results have been reported by previous studies on blended learning. This study evaluated the effectiveness of embedding a teacher-supervised online discussion platform in a blended embryology course in terms of its impact on students\' capabilities to handle difficult and cognitively challenging tasks.
METHODS: Two forms of blended learning were investigated and compared in this study. Students in the control group (n = 85) learned online materials before each class, followed by classroom instruction and activities in which face-to-face discussion and communication between students were encouraged. Students in the experimental group (n = 83) followed a similar procedure with an additional teacher-supervised online discussion platform to guide, supervise and evaluate their learning progress. All participants were first-year medical students in clinical medicine at Dalian Medical University who had enrolled in 2017. All participants took the final exam to test their learning outcomes.
RESULTS: The embryology grades of students in the experimental group were significantly higher than those of students in the control group (p = 0.001). Additionally, the scores of students in the experimental group on questions with a high difficulty level (p = 0.003) and questions assessing high-order cognitive skills (p = 0.003) were higher than those of students in the control group; the effect size was moderate (η2 > 0.05).
CONCLUSIONS: In blended embryology courses, compared with learner-led and face-to-face discussion, the teacher-supervised online discussion platform has great potential to enable students to achieve higher grades and solve difficult and cognitively challenging tasks.

The pandemic of COVID-19 disease has caused severe impact globally. Governments consider vaccination as an effective measure to control pandemic. However, many people have been hesitant to receive COVID-19 vaccine, particularly periconceptional and lactating women. Although research has indicated that pregnant women with COVID-19 are at a higher risk of adverse pregnancy and birth outcomes, as well as severe illness. There appears to be a lack of systematic and comprehensive evidence of the prevalence and determinants of COVID-19 vaccine hesitancy among periconceptional and lactating women. As a result, it has been essential to investigate periconceptional and lactating women\'s vaccination views and behaviours. This study will review articles on vaccine hesitancy among periconceptional and lactating women to assess the impact of the COVID-19 vaccine hesitancy during the pandemic.
We will systematically search observational studies from 1 November 2019 to 30 October 2021 in the following databases: Web of Science, PubMed, EMBASE, MEDLINE, Cochrane Library, EBSCO, WHO COVID-19 Database, CNKI and WanFang Database. The following medical subject headings and free-text terms will be used: \"COVID-19 vaccines\" AND \"female\" AND \"vaccine hesitancy\". Eligibility criteria are as follows: population (women of reproductive age); exposure (currently pregnant, lactational or trying to get pregnant); comparison (general women who are not in preconception, gestation or lactation) and outcome (the rate of COVID-19 vaccine hesitancy). Article screening and data extraction will be undertaken independently by two reviewers, and any discrepancy will be resolved through discussion. We will use I2 statistics to assess heterogeneity and perform a meta-analysis when sufficiently homogeneous studies are provided. We will explore the potential sources of heterogeneity using subgroup and meta-regression analysis.
This study will use published data, so ethical approval is not required. The findings will be disseminated by publication in peer-reviewed journal(s).
CRD42021257511.

Rapid multicolor three-dimensional (3D) imaging for centimeter-scale specimens with subcellular resolution remains a challenging but captivating scientific pursuit. Here, we present a fast, cost-effective, and robust multicolor whole-organ 3D imaging method assisted with ultraviolet (UV) surface excitation and vibratomy-assisted sectioning, termed translational rapid ultraviolet-excited sectioning tomography (TRUST). With an inexpensive UV light-emitting diode (UV-LED) and a color camera, TRUST achieves widefield exogenous molecular-specific fluorescence and endogenous content-rich autofluorescence imaging simultaneously while preserving low system complexity and system cost. Formalin-fixed specimens are stained layer by layer along with serial mechanical sectioning to achieve automated 3D imaging with high staining uniformity and time efficiency. 3D models of all vital organs in wild-type C57BL/6 mice with the 3D structure of their internal components (e.g., vessel network, glomeruli, and nerve tracts) can be reconstructed after imaging with TRUST to demonstrate its fast, robust, and high-content multicolor 3D imaging capability. Moreover, its potential for developmental biology has also been validated by imaging entire mouse embryos (~2 days for the embryo at the embryonic day of 15). TRUST offers a fast and cost-effective approach for high-resolution whole-organ multicolor 3D imaging while relieving researchers from the heavy sample preparation workload.

Morphological evaluation is used to select embryos for in vitro fertilisation. However, it does not fully reflect the implantation potential. Preimplantation genetic testing for aneuploidies (PGT-A) can detect embryonic aneuploidy, but biopsy procedure is invasive. Currently, a non-invasive PGT (ni-PGT) approach using spent medium is being evaluated. However, the clinical benefit of ni-PGT has not been clearly demonstrated. A multicentre randomised trial is needed to verify whether ni-PGT can be an new effective tool for evaluating embryos.
Overall, 1148 couples aged 35~42 (women) receiving in vitro fertilization-intracytoplasmic sperm injection are planned to be enrolled. Couples will be digitally randomised to (1) ni-PGT and (2) conventional morphology groups at a 1:1 treatment ratio. The primary outcome will be the ongoing pregnancy rate related to the first transfer cycle within 6 months after oocyte retrieval.
The study protocol is approved by the Ethics Committee of Peking University Third Hospital and the participating hospitals. The results will be disseminated through international conferences and scientific journals.
NCT04339166.