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1.
Nat Commun ; 11(1): 5275, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077725

RESUMO

The anterior pituitary gland plays a central role in regulating various physiological processes, including body growth, reproduction, metabolism and stress response. Here, we perform single-cell RNA-sequencing (scRNA-seq) of 4113 individual cells from human fetal pituitaries. We characterize divergent developmental trajectories with distinct transitional intermediate states in five hormone-producing cell lineages. Corticotropes exhibit an early intermediate state prior to full differentiation. Three cell types of the PIT-1 lineage (somatotropes, lactotropes and thyrotropes) segregate from a common progenitor coexpressing lineage-specific transcription factors of different sublineages. Gonadotropes experience two multistep developmental trajectories. Furthermore, we identify a fetal gonadotrope cell subtype expressing the primate-specific hormone chorionic gonadotropin. We also characterize the cellular heterogeneity of pituitary stem cells and identify a hybrid epithelial/mesenchymal state and an early-to-late state transition. Here, our results provide insights into the transcriptional landscape of human pituitary development, defining distinct cell substates and subtypes and illustrating transcription factor dynamics during cell fate commitment.

2.
Sci Adv ; 6(34): eaaz2978, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32923614

RESUMO

Neurogenesis processes differ in different areas of the cortex in many species, including humans. Here, we performed single-cell transcriptome profiling of the four cortical lobes and pons during human embryonic and fetal development. We identified distinct subtypes of neural progenitor cells (NPCs) and their molecular signatures, including a group of previously unidentified transient NPCs. We specified the neurogenesis path and molecular regulations of the human deep-layer, upper-layer, and mature neurons. Neurons showed clear spatial and temporal distinctions, while glial cells of different origins showed development patterns similar to those of mice, and we captured the developmental trajectory of oligodendrocyte lineage cells until the human mid-fetal stage. Additionally, we verified region-specific characteristics of neurons in the cortex, including their distinct electrophysiological features. With systematic single-cell analysis, we decoded human neuronal development in temporal and spatial dimensions from GW7 to GW28, offering deeper insights into the molecular regulations underlying human neurogenesis and cortical development.

3.
Cell Res ; 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32884136

RESUMO

Proper development of fetal germ cells (FGCs) is vital for the precise transmission of genetic and epigenetic information through generations. The transcriptional landscapes of human FGC development have been revealed; however, the epigenetic reprogramming process of FGCs remains elusive. Here, we profiled the genome-wide DNA methylation and chromatin accessibility of human FGCs at different phases as well as gonadal niche cells at single-cell resolution. First, we found that DNA methylation levels of FGCs changed in a temporal manner, whereas FGCs at different phases in the same embryo exhibited comparable DNA methylation levels and patterns. Second, we revealed the phase-specific chromatin accessibility signatures at the promoter regions of a large set of critical transcription factors and signaling pathway genes. We also identified potential distal regulatory elements including enhancers in FGCs. Third, compared with other hominid-specific retrotransposons, SVA_D might have a broad spectrum of binding capacity for transcription factors, including SOX15 and SOX17. Finally, using an in vitro culture system of human FGCs, we showed that the BMP signaling pathway promoted the cell proliferation of FGCs, and regulated the WNT signaling pathway by orchestrating the chromatin accessibility of its ligand genes. Our single-cell epigenomic atlas and functional assays provide valuable insights for understanding the strongly heterogeneous, unsynchronized, yet highly robust nature of human germ cell development.

4.
Front Med ; 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876878

RESUMO

Oocyte cryopreservation is widely used for clinical and social reasons. Previous studies have demonstrated that conventional slow-freezing cryopreservation procedures, but not storage time, can alter the gene expression profiles of frozen oocytes. Whether vitrification procedures and the related frozen storage durations have any effects on the transcriptomes of human metaphase II oocytes remain unknown. Four women (30-32 years old) who had undergone IVF treatment were recruited for this study. RNA-Seq profiles of 3 fresh oocytes and 13 surviving vitrified-thawed oocytes (3, 3, 4, and 3 oocytes were cryostored for 1,2, 3, and 12 months) were analyzed at a single-cell resolution. A total of 1987 genes were differentially expressed in the 13 vitrified-thawed oocytes. However, no differentially expressed genes were found between any two groups among the 1-, 2-, 3-, and 12-month storage groups. Further analysis revealed that the aberrant genes in the vitrified oocytes were closely related to oogenesis and development. Our findings indicated that the effects of vitrification on the transcriptomes of mature human oocytes are induced by the procedure itself, suggesting that long-term cryostorage of human oocytes is safe.

5.
Aging (Albany NY) ; 12(18): 18251-18273, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32986013

RESUMO

Due to the current delay in childbearing, the importance of elucidating the underlying mechanisms for reproductive aging has increased. Human fertility is considered to be controlled by hormones secreted by the hypothalamic-pituitary-gonadal axis. To clarify the changes in hypothalamic gene expression with increasing age, we performed paired-end strand-specific total RNA sequencing for the hypothalamus tissues of rhesus. We found that hypothalamic gene expression in females was more susceptible to aging than that in males, and reproductive aging in females and males might have different regulatory mechanisms. Intriguingly, the expression of most of the hormones secreted by hypothalamus showed no significant difference among the macaques grouped by age and gender. Moreover, the age-related housekeeping genes in females were enriched in neurodegenerative disorders- and metabolic-related pathways. This study provides evidence that aging may influence hypothalamic gene expression through different mechanisms in females and males and may involve some nonhormonal pathways, which helps further elucidate the process of reproductive aging and improve clinical fertility assessment in mid-aged women.

6.
Reprod Biomed Online ; 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32978073

RESUMO

RESEARCH QUESTION: Does patient-oriented strategies encompassing individualized oocyte number (POSEIDON) classification help stratify the reproductive potential of patients with low prognosis more effectively from the perspective of prognosis; and as cumulative live birth rate (CLBR) is an effect indication, how is CLBR in patients stratified using POSEIDON? DESIGN: A retrospective cohort study of 10,615 women who underwent IVF treatment at the Peking University Third Hospital between January 2017 and December 2017. Patients were stratified according to POSEIDON criteria. Clinical characteristics, fresh embryo transfer outcomes and CLBR during the first two ovarian stimulation cycles were recorded. RESULTS: Gonadotrophin-releasing hormone antagonist protocol was the most used treatment in both ovarian stimulation cycles. After the failure of the first IVF treatment, 2063 (29.2%) women continued the second treatment, and 10.9% of them switched to the micro-stimulation protocol. Compared with the non-POSEIDON group, the CLBR of the first cycle in each POSEIDON group was lower (P < 0.001). The CLBRs of the second cycle in older patients (POSEIDON groups 2b and 4) and in younger patients with poor ovarian reserve (POSEIDON group 3) were lower than that in non-POSEIDON group (group 2b, P = 0.001; group 3, P = 0.019; group 4, P < 0.001). Subgroup analysis showed that younger patients had higher CLBR than older patients in both cycles (P < 0.001). CONCLUSION: The CLBRs vary among different POSEIDON groups. The results may help reproductive specialists to understand the characteristics of low prognosis patients better and to develop individualized treatment plans.

7.
Womens Health (Lond) ; 16: 1745506520928617, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32894698

RESUMO

OBJECTIVE: To investigate the prevalence and the related characteristics of oligomenorrhea among women within childbearing age in China. STUDY DESIGN: A large-scale community-based investigation was conducted from 2013 to 2015. A total of 12,964 women aged 18-49 years from 9 provinces/municipalities in China were recruited for healthcare screening in local community health centers. Outcome measures include clinical history, ultrasonographic exam, and hormonal and metabolic parameters. RESULTS: Among women within childbearing age in China, the prevalence of oligomenorrhea was 12.2% (1,579/12,964). Both sociodemographic factors and medical history were significantly associated with oligomenorrhea (P < 0.05). In such women, the prevalence of obesity, acne, seborrhea, acanthosis, larger ovarian size, and polycystic ovarian morphology was higher when compared with normal women; the prevalence of anti-Mullerian hormone, total testosterone, and androstenedione (P < 0.05) was higher as well. The infertility rates of all women were higher in the oligomenorrhea group (17.2%, 272/1,579) than in the non-oligomenorrhea group (9.0%, 1,024/11,385), and among women without contraception, for the oligomenorrhea group, the infertility rate was 32.5% (128/394), and for the non-oligomenorrhea group, 17.9% (400/2,240). In the oligomenorrhea group, 57.4% (156/272) of the women underwent treatments for infertility, which was higher than the non-oligomenorrhea group 36.1% (370/1,024). CONCLUSIONS: Obesity, acne, seborrhea, acanthosis, larger ovarian size, and polycystic ovarian morphology were significantly associated with oligomenorrhea. The increase of anti-Mullerian hormone, total testosterone, and androstenedione level was also demonstrated in the oligomenorrhea group. Higher prevalence of infertility and medical treatment rate was observed in women with oligomenorrhea.

8.
Phys Chem Chem Phys ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966363

RESUMO

Molybdenum disulfide (MoS2) is one of the two-dimensional layered semiconductor transition metal dichalcogenides (TMDCs) with great potential in electronics, optoelectronics, and spintronic devices. Sulfur vacancies in MoS2 are the most prevalent defects. However, the effect of sulfur vacancies on the electronic structure of MoS2 is still in dispute. Here we experimentally and theoretically investigated the effect of sulfur vacancies in MoS2. The vacancies were intentionally introduced by thermal annealing of MoS2 crystals in a vacuum environment. Angle-resolved photoemission spectroscopy (ARPES) was used directly to observe the electronic structure of the MoS2 single crystals. The experimental result distinctly revealed the appearance of an occupied defect state just above the valence band maximum (VBM) and an upward shift of the VBM after creating sulfur vacancies. In addition, density functional theory (DFT) calculations also confirmed the existence of the occupied defect state close to the VBM as well as two deep unoccupied states induced by the sulfur vacancies. Our results provide evidence to contradict that sulfur vacancies indicate the origin of n-type behaviour in MoS2. This work provides a rational strategy for tuning the electronic structures of MoS2.

9.
Front Med ; 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32926320

RESUMO

This study aimed to evaluate the efficacy of Chinese herbal medicine (CHM) in patients with severe/critical coronavirus disease 2019 (COVID-19). In this retrospective study, data were collected from 662 patients with severe/critical COVID-19 who were admitted to a designated hospital to treat patients with severe COVID-19 in Wuhan before March 20, 2020. All patients were divided into an exposed group (CHM users) and a control group (non-users). After propensity score matching in a 1:1 ratio, 156 CHM users were matched by propensity score to 156 non-users. No significant differences in seven baseline clinical variables were found between the two groups of patients. All-cause mortality was reported in 13 CHM users who died and 36 non-users who died. After multivariate adjustment, the mortality risk of CHM users was reduced by 82.2% (odds ratio 0.178, 95% CI 0.076-0.418; P < 0.001) compared with the non-users. Secondly, age (odds ratio 1.053, 95% CI 1.023-1.084; P < 0.001) and the proportion of severe/critical patients (odds ratio 0.063, 95% CI 0.028-0.143; P < 0.001) were the risk factors of mortality. These results show that the use of CHM may reduce the mortality of patients with severe/critical COVID-19.

10.
Biomed Chromatogr ; : e4993, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32986877

RESUMO

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic disorder in women of reproductive age. Some studies have investigated metabolic alterations in plasma and follicular fluid (FF) from PCOS patients, but they did not control for obesity or insulin resistance (IR); additionally, correlation analysis of metabolites is sparse. Accordingly, in this study, we aimed to examine metabolic differences due to the pathogenesis of PCOS and identify the hub metabolites and investigate its associations with androgens. We applied GC-MS platform coupled with correlation network approach to analyze FF samples from 32 PCOS patients without obesity and IR and 31 healthy women. Thirty significantly altered metabolites in PCOS patients were enriched in amino acid metabolism. L-Phenylalanine, L-tryptophan, pyroglutamic acid, L-tyrosine, L-leucine and L-valine were screened as hub metabolites in metabolic correlation network. Among them, increased L-tryptophan and L-tyrosine were altered hub metabolites, and they had a more significant impact on the metabolic change of PCOS. In addition, L-tryptophan and L-tyrosine were significantly positively associated with serum androgens levels in the PCOS. Our results suggested that disorders of amino acid metabolism, especially tryptophan and tyrosine metabolism, might play an important role in the development of PCOS in predisposed women without obesity and IR.

11.
Chem Commun (Camb) ; 56(83): 12616-12619, 2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-32955044

RESUMO

Cas12a ribonucleoprotein (RNP) is an RNA-guided CRISPR-associated nuclease used widely for genome editing and molecular diagnostics. Conventional detection methods rely on adopting antibody-based reagents that are expensive and lack scalability, and, moreover, only detect Cas12 enzyme rather than RNP, which is the true effector. Here, we describe a method for the rapid and quantitative detection of the effective Cas12a RNPs by the combined use of anti-CRISPR protein AcrVA1 and stem-loop RT-qPCR, achieving a limit of detection (LOD) of 1 fM in reaction buffer and 0.1 pM under biologically representative conditions.

14.
IEEE Trans Med Imaging ; PP2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32746135

RESUMO

Chromosome enumeration is an essential but tedious procedure in karyotyping analysis. To automate the enumeration process, we develop a chromosome enumeration framework, DeepACEv2, based on the region based object detection scheme. The framework is developed following three steps. Firstly, we take the classical ResNet-101 as the backbone and attach the Feature Pyramid Network (FPN) to the backbone. The FPN takes full advantage of the multiple level features, and we only output the level of feature map that most of the chromosomes are assigned to. Secondly, we enhance the region proposal network's ability by adding a newly proposed Hard Negative Anchors Sampling to extract unapparent but essential information about highly confusing partial chromosomes. Next, to alleviate serious occlusion problems, besides the traditional detection branch, we novelly introduce an isolated Template Module branch to extract unique embeddings of each proposal by utilizing the chromosome's geometric information. The embeddings are further incorporated into the No Maximum Suppression (NMS) procedure to improve the detection of overlapping chromosomes. Finally, we design a Truncated Normalized Repulsion Loss and add it to the loss function to avoid inaccurate localization caused by occlusion. In the newly collected 1375 metaphase images that came from a clinical laboratory, a series of ablation studies validate the effectiveness of each proposed module. Combining them, the proposed DeepACEv2 outperforms all the previous methods, yielding the Whole Correct Ratio(WCR)(%) with respect to images as 71.39, and the Average Error Ratio(AER)(%) with respect to chromosomes as about 1.17.

16.
Sci China Life Sci ; 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32860578

RESUMO

Primordial germ cells (PGCs) are precursors of both male and female gametes as fundamental materials for organism development. The transcriptome, methylome, and chromatin accessibility profiles of PGCs in both mice and humans have been recently reported. However, little is known about the characteristics of PGCs at the protein levels, which directly exert cellular functions. Here, we construct landscapes of both proteome and 3D spatial distribution of mouse PGCs at E11.5, E13.5 and E16.5 days, the three critical developmental windows for PGCs, sex differentiation, female meiosis initiation and male mitotic arrest. In each developmental stage of PGCs, nearly 2,000-3,000 proteins are identified, among which specific functional pathways such as oxidative phosphorylation, DNA damage repair, and meiotic cell cycle are involved for different events during PGCs development. Interestingly, by 3D modeling we find that PGCs spatially cluster into around 1,300 nests in genital ridge at E11.5 and the nest number is not increased by the exponential proliferation of PGCs. Comparative analysis of our proteomic data with published transcriptomic data does not show a close correlation, meaning that the practically executive factors are beyond the transcriptome. Thus, our work offers a valuable resource for the systematic investigations of PGC development at protein level and spatial map.

18.
Reprod Sci ; 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32840740

RESUMO

This study aims to evaluate the effect of blastocyst- and cleavage-stage embryo transfers with different numbers of transferred embryos on pregnancy outcomes in China. This was a retrospective cohort study that collected 24,422 frozen-thawed embryo transfer (FET) cycles in two affiliated hospitals of Peking University Health Science Center between January 2015 and May 2018. They were divided into four groups: the single cleavage-stage embryo transfer group (C-1) (763 cycles), double cleavage-stage embryo transfer group (C-2) (13,004 cycles), single blastocyst-stage embryo transfer group (B-1) (7913 cycles), and double blastocyst-stage embryo transfer group (B-2) (2046 cycles). Of the four groups, the live birth rate was the lowest in the C-1 group (11.8%) while it was the highest in the B-2 group (33.6%). However, the B-2 group was accompanied with higher risks of miscarriages, maternal complications, twin births, preterm births, and low birth weight. Compared with the C-2 group, the B-1 group had a lower live birth rate (23.0 vs 29.0%; aOR, 0.78; 95% CI, 0.72-0.85), but also had a lower risk for twin births (1.9 vs 23.4%; aOR, 0.06; 95% CI, 0.04-0.09) and preterm births (9.6 vs 16.1%; aOR, 0.51; 95% CI, 0.41-0.65). The probability of live birth in the B-1 group declined from 0.25 at 20-29 years old to 0.08 at > 40 years old, while the probabilities of adverse outcomes went up with maternal age. It can be concluded that single-blastocyst embryo transfer seems to be the best choice for all maternal ages. This group of embryo transfer has significantly reduced adverse neonatal outcomes. Especially, women with younger maternal age in this group appear to prominently benefit from single-blastocyst transfer.

19.
Cell Cycle ; 19(17): 2182-2194, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32779509

RESUMO

Different strategies of ovarian stimulation are widely used in IVF to retrieve mature metaphase II (MII) oocytes for fertilization. On average, approximately 70% of recovered oocytes are mature, while personalized administration of hCG and/or GnRH agonist trigger and in vitro maturation (IVM) management can further improve the maturation rate. However, even under such conditions, a complete absence of oocyte maturation is still observed sporadically. The probable causes for such maturation-deficient (MD) oocytes - which arrest abnormally at metaphase I (MI) stage - are still under investigation. In the present study, using single-cell transcriptomic RNA sequencing (RNA-seq) and differential expression analysis, we showed that gene expression profiles were aberrant, and alternative splicing (AS) patterns were changed in MD oocytes when compared with normally mature (MN) oocytes. Gene ontology (GO) enrichment demonstrated that the differently expressed genes (DEGs) were mostly correlated with pre-mRNA splicing, RNA transportation, RNA processing, and mRNA regulation. Subsequently, analysis of AS events revealed that genes with altered AS patterns were primarily associated with metabolism and cell cycle. With these findings, we have demonstrated aberrant gene expression in complete maturation-deficient oocytes, and we propose that alterations in post-transcriptional regulation constitute a potential underlying mechanism governing oocyte maturation.

20.
Fertil Steril ; 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32826046

RESUMO

OBJECTIVE: To evaluate the obstetric and neonatal outcomes after the transfer of vitrified-warmed single blastocysts developing from nonpronuclear (0PN) and monopronuclear (1PN) zygotes. DESIGN: Cohort study. SETTING: Affiliated hospital. PATIENT(S): This study was a retrospective analysis of 435 0PN and 281 1PN vitrified-warmed single blastocyst transfers, and 151 0PN and 75 1PN singletons, compared with 13,167 two-pronuclear (2PN) vitrified-warmed single blastocyst transfers and 4,559 2PN singletons, respectively. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Pregnancy rate (PR), abortion rate (AR), live birth rate (LBR), and singleton birthweight were the primary outcome measures. RESULT(S): PR, AR, and LBR were similar when compared between the 0PN and 2PN groups after vitrified-warmed blastocyst transfer. However, the 0PN group had a higher birthweights, higher z scores, and a greater proportion of very large for gestational age newborns. When comparing the 1PN and 2PN groups, we found that the PR was similar whereas the AR was higher and the LBR was lower. No differences were detected in the other neonatal outcomes. CONCLUSION(S): The results of the present study show that the transfer of 2PN blastocysts should be prioritized because of a higher AR and a lower LBR after 1PN blastocyst transfers and a higher birthweight after 0PN blastocyst transfers when compared with 2PN blastocyst transfers. Our data indicate the need for concern about the safety of 1PN and 0PN embryo transfers.

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