Publications by authors named "Jinghe Liu"

Introduction: Novel coronavirus pneumonia (COVID-19) is an acute respiratory disease caused by the novel coronavirus SARS-CoV-2. Severe and critical illness, especially secondary bacterial infection (SBI) cases, accounts for the vast majority of COVID-19-related deaths. However, the relevant biological indicators of COVID-19 and SBI are still unclear, which significantly limits the timely diagnosis and treatment.

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It is presently unknown whether imported cases of the 2019 coronavirus disease (COVID-19) have different characteristics when compared with local cases. To compare the clinical characteristics of local cases of COVID-19 in China compared with those imported from abroad.This was a retrospective study of confirmed cases of COVID-19 admitted at the Beijing Ditan Fever Emergency Department between February 29th, 2020, and March 27th, 2020.

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Herein, we systematically explored the electronic properties of Sc-based MXenes via first-principles calculations, with the aim to extend their applicability. OH-Functionalized carbides and OH/SH-terminated nitrides manifest ultralow work functions, potential in field-effect transistors. Furthermore, we identified three novel semiconductors (ScCCl, ScC(SH), and ScNO).

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Novel all-solid-state microsupercapacitors (MSCs) with three-dimensional (3D) electrodes consisting of active materials (i.e., graphene or activated carbon (AC) particles) and polymer electrolyte (PE) designed for high-energy-density storage applications were fabricated and tested in this work.

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The final step of cytokinesis is abscission when the intercellular bridge (ICB) linking the two new daughter cells is broken. Correct construction of the ICB is crucial for the assembly of factors involved in abscission, a failure in which results in aneuploidy. Using live imaging and subdiffraction microscopy, we identify new anillin-septin cytoskeleton-dependent stages in ICB formation and maturation.

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Cell division is achieved by a plasma membrane furrow that must ingress between the segregating chromosomes during anaphase [1-3]. The force that drives furrow ingression is generated by the actomyosin cytoskeleton, which is linked to the membrane by an as yet undefined molecular mechanism. A key component of the membrane furrow is anillin.

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We previously reported that fetal porcine skin-derived stem cells were capable of differentiation into oocyte-like cells (OLCs). Here we report that newborn mice skin-derived stem cells are also capable of differentiating into early OLCs. Using stem cells from mice that are transgenic for Oct4 germline distal enhancer-GFP, germ cells resulting from their differentiation are expected to be GFP(+).

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Neodymium-doped gadolinium gallium garnet (Nd:GGG)crystal is the best operation material of solid-state heat-capacity laser. In the present paper, Nd:GGG single crystal was grown by Czochralski (Cz) method. Fluorescence spectra and absorption spectra were measured.

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Deleted in Azoospermia-Like (DAZL) is known to play an important role during both spermatogenesis and oogenesis, as mutations in this gene may result in male and female sterility. In order to study the expression of DAZL in the pig, we cloned the full-length coding sequence and determined its mRNA and protein expression profile in the ovary and in oocytes undergoing in vitro maturation (IVM). Immunohistochemisty revealed that DAZL protein localizes to oocytes of both preantral and antral follicles.

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High rate of abortion and developmental abnormalities is thought to be closely associated with inefficient epigenetic reprogramming of the transplanted nuclei during bovine cloning. It is known that one of the important mechanisms for epigenetic reprogramming is DNA methylation. DNA methylation is established and maintained by DNA methyltransferases (DNMTs), therefore, it is postulated that the inefficient epigenetic reprogramming of transplanted nuclei may be due to abnormal expression of DNMTs.

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Yb(x) : KY(1-x)W (x = 0.05)and KYbW crystals were grown by TSSG method. Both of the structure and spectral properties were compared.

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To gain a better understanding of the methylation imprinting changes associated with heat stress in early development, we used bisulfite sequencing and bisulfite restriction analysis to examine the DNA methylation status of imprinted genes in early embryos (blastocysts). The paternal imprinted genes, H19 and Igf-2r, had lower methylation levels in heat-stressed embryos than in control embryos, whereas the maternal imprinted genes, Peg3 and Peg1, had similar methylation pattern in heat-stressed embryos and in control embryos. Our results indicate that heat stress may induce aberrant methylation imprinting, which results in developmental failure of mouse embryos, and that the effects of heat shock on methylation imprinting may be gene-specific.

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Prolonged residence of postovulatory oocyte in the oviduct or prolonged culture in vitro can lead to oocyte aging, which significantly affects pre- and post-implantation embryo development. In this study, we employed bisulfite sequencing and COBRA methods to investigate the DNA methylation status of differentially methylated regions (DMRs) of Snrpn and Peg1/Mest, two maternally imprinted genes, in postovulatory oocytes aged in vivo and in vitro. The results showed that Snrpn DMR was clearly demethylated in oocytes aged in vivo at 29h post-hCG and in denuded oocytes aged in vitro for the same time period.

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Epigenetic modifications are closely associated with embryo developmental potential. One of the epigenetic modifications thought to be involved in genomic imprinting is DNA methylation. Here we show that the maternally imprinted genes Snrpn and Peg1/Mest were nearly unmethylated or heavily methylated, respectively, in their differentially methylated regions (DMRs) at the two-cell stage in parthenogenetic embryos.

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Genomic imprinting plays a very important role during development and its abnormality may heavily undermine the developmental potential of bovine embryos. Because of limited resources of the cow genome, bovine genomic imprinting, both in normal development and in somatic cell nuclear transfer (SCNT) cloning, is not well documented. DNA methylation is thought to be a major factor for the establishment of genomic imprinting.

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We recently reported that MEK1/2 plays an important role in microtubule organization and spindle pole tethering in mouse oocytes, but how the intracellular transport of this protein is regulated remains unknown. In the present study, we investigated the mechanisms of poleward MEK1/2 transport during the prometaphase I/metaphase I transition and MEK1/2 release from the spindle poles during the metaphase I/anaphase I transition in mouse oocytes. Firstly, we found that p-MEK1/2 was colocalized with dynactin at the spindle poles.

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So far, standard follicle culture systems can produce blastocyst from less than 40% of the in vitro matured oocytes compared to over 70% in the in vivo counterpart. Because the capacity for embryonic development is strictly associated with the terminal stage of oocyte growth, the nuclear maturity status of the in vitro grown oocyte was the subject of this study. Mouse early preantral follicles (100-130 microm) and early antral follicles (170-200 microm) isolated enzymatically were cultured for 12 and 4 days, respectively, in a collagen-free dish.

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In mitosis the checkpoint proteins ensure faithful chromosome segregation by delaying onset of anaphase until all sister chromatids align at the metaphase plate of the bipolar spindle correctly. In the present study we blocked the function of Bub1 during meiosis by microinjecting anti-Bub1 specific antibody into cytoplasm of mouse oocytes, and found that depletion of Bub1 induced evident cyclin B degradation and precocious anaphase onset. Bub1 suppression also overrode the checkpoint-dependent cell cycle arrest provoked by a low dosage of nocodazole.

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Spindle checkpoint proteins control entry into anaphase and chromosome segregation. As a member of spindle checkpoint proteins, MAD2 takes a central role in the regulation of anaphase onset and genome integrity. Here, we used MAD2 siRNA transfection approach to study MAD2 functions during mouse oocyte meiotic maturation in vitro.

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DNA methylation/demethylation of donor genomes in recipient ooplasm after nuclear transfer occurs in a species-specific way. In cloned rabbit and bovine embryos, repetitive sequences maintain the donor-type methylation status, but typical demethylation of repetitive sequences takes place in cloned porcine embryos. To clarify whether the demethylation is controlled by donor nucleus intrinsic property or by recipient ooplasm, we used interspecies somatic cell nuclear transfer (iSCNT) model to examine the methylation status of repetitive sequences in pig-to-rabbit and rabbit-to-pig interspecies embryos.

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Cloned bovines have a much higher abortion rate than those derived in vivo. Available evidence indicates that inappropriate epigenetic reprogramming of donor nuclei is the primary cause of cloning failure. To gain a better understanding of the DNA methylation changes associated with the high abortion rate of cloned bovines, we examined the DNA methylation status of a repeated sequence (satellite I) and the promoter regions of two single-copy genes (interleukin 3/cytokeratin) in aborted cloned fetuses, aborted fetuses derived from artificial insemination (AI), cloned adults and AI adults by bisulfite sequencing and restriction enzyme analysis.

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