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Chicken embryonic stem cells (cESCs) isolated from the egg at the stage X hold great promise for cell therapy, tissue engineering, pharmaceutical, and biotechnological applications. They are considered to be pluripotent cells with the capacity to self-renewal and differentiate into specialized cells. However, long-term maintenance of cESCs cannot be realized now, which impedes the establishment of cESC line and limits their applications. Therefore, the separation locations, isolation methods, and culture conditions especially the supplements and action mechanisms of cytokines, including leukemia inhibitory factor, fibroblast growth factor, transforming growth factor beta, bone morphogenic protein, and activin for cESCs in vitro, have been reviewed here. These defined strategies will contribute to identify the key mechanism on the self-renewal of cESCs, facilitate to optimize system that supports the derivation and longtime maintenance of cESCs, establish the cESC line, and develop the biobank of genetic resources in chicken.

To improve the isolation efficiency of parthenogenetic embryonic stem cells (pESCs) in mice, it is necessary to optimize the method to increase in vitro developmental competence of mice parthenogenetic blastocysts. Therefore, this study aims to investigate an optimal method for the production of mouse parthenogenetic blastocysts and isolation of pESC colonies by comparing the effects of two methods: (1) the treatment of histone deacetylase inhibitor PXD101 before, during, or after parthenogenetic activation; (2) parthenogenetic embryo aggregation; and (3) their combination treatment. The results suggest that application of PXD101 treatment and embryo aggregation could both improve the development of mouse parthenogenetic blastocysts (50 nM PXD101 treated 4 hours during activation and further 4 hours after activation: 40.0% vs. 20.0%; p

Reprogramming mediated with proteins provides a novel, simpler, and safer strategy for generating induced pluripotent stem cells (iPSCs); in order to efficiently produce the recombination proteins and optimize the gene delivery system, different agents were screened to efficiently transfect plasmid DNA (pDNA) encoding “Yamanaka factor” (Oct 4, Sox 2, Klf 4, or c-Myc) into human embryonic kidney (HEK)-293T cells. The results indicated that 10 μg/mL Poly-MAG (polyethyleneimine (PEI)-MIONP) combined with exogenous magnetic field, 5 μg/mL Lipofectamine® 2000, and 40 μg/mL PEI were, respectively, more suitable to deliver the pDNA encoding Oct 4 into HEK-293T cells in the same transfection reagent groups, but the cell survival rate in 10 μg/mL Poly-MAG treatment group was significantly higher than that in the latter two groups (P

Based on the typical mission requirement of near space aircraft and the former integrated analysis model, a new high speed aircraft/combined power integration analysis model which considered angle of attack and climb was developed. Aiming at the wide operation range characters of high speed aircraft, the paper predicted the lift and drag characteristics of high speed aircraf and classified the aircraft to different generations according to the highest lift-to-drag ratio. In the last part, the contraint analysis and mission assessment of intergration were accomplished and the ability of completing mission of the steamjet and tandem TBCC engines was contrasted by using the high speed intergration design and analysis program. According to the results of calculation, several conculsions were reached. The steamjet with better reliability and maneuverability but shorter range can be used to realize the scheudled target of high speed aircraft in a short time; otherwise, the tandem TBCC engine with worse reliability were suited for carrying out long range mission because of its high impluse in the whole flight Mach condition.

Magnetic iron oxide nanoparticles (MIONPs) are particularly attractive in biosensor, antibacterial activity, targeted drug delivery, cell separation, magnetic resonance imaging tumor magnetic hyperthermia, and so on because of their particular properties including superparamagnetic behavior, low toxicity, biocompatibility, etc. Although many methods had been developed to produce MIONPs, some challenges such as severe agglomeration, serious oxidation, and irregular size are still faced in the synthesis of MIONPs. Thus, various strategies had been developed for the surface modification of MIONPs to improve the characteristics of them and obtain multifunctional MIONPs, which will widen the applicational scopes of them. Therefore, the processes, mechanisms, advances, advantages, and disadvantages of six main approaches for the synthesis of MIONPs; surface modification of MIONPs with inorganic materials, organic molecules, and polymer molecules; applications of MIONPs or modified MIONPs; the technical challenges of synthesizing MIONPs; and their limitations in biomedical applications were described in this review to provide the theoretical and technological guidance for their future applications.

Lineage reprogramming has become a potential strategy for therapy of cardiac diseases. Somatic cells can be directly converted into the induced cardiomyocytes (iCMs) without passing through an induced pluripotent stem cell stage; this strategy has some advantages such as directional differentiation and preferable security. However, there are still many challenges which need to be further studied, such as identification of safer induced factors, exploration of molecular mechanisms, improvement of the mature level of iCMs and so on. Therefore, the structures of key factors, including transcription factors, microRNAs (miRNAs), epigenetic regulators and small molecules and their functions in the cardiac development and lineage reprogramming, molecular mechanisms underlying lineage conversion, strategies for generating matured iCMs, and major challenges were reviewed to lay the foundation for further applications of iCMs.

Some discoveries resulted from 2-dimensional (2D) cultured cardiac cells have been disqualified in animal testing and later clinical trials. Extracellular matrix (ECM) plays a vital role in cardiac homeostasis, cardiac ECM (cECM)-based 3D cell cultures can mimics the physiological and pathological conditions in vivo closely, it is hopeful of addressing this challenge. Construction of cECM-based 3-dimensional (3D) hydrogel (cECM3DH) and its effects on cell behaviors were studied here. The results indicated that cellular compartments could be efficiently removed from heart tissue via sodium dodecyl sulfonate (SDS)- and Triton X-100-mediated decellularization, remaining the natural fibrous network structure and major proteins. 3D hydrogel consisted of 1 × 107 cells/mL cells and 75% cECM could promote the proliferation and anti-apoptosis ability of human embryonic kidney (HEK)-293T cells. 0.25% trypsin or 0.20% collagenase was suitable to retrieve these cells from 3D hydrogel for further researches. Compared with 2D culture system, cECM3DH could significantly increase the proportion of GATA 4+ cardiomyocytes (CMs) derived from heart tissue of neonatal mouse or induced differentiation of embryonic stem cells (ESCs) (P

In order to improve the gene-delivering efficiency of polyethylenimine-modified superparamagnetic iron oxide nanoparticle (PEI-SPION) and elucidate the related mechanisms, the binding ratio and protection actions of PEI-SPION to plasmid DNA (pDNA), the physical characteristics of PEI-SPION/pDNA complex, and effects of exogenous factors (including magnetic field, inhibitors, and activator) on gene transfection in human embryonic kidney 293T cells (HEK-293T cells) were explored here. The results showed that the diameter of PEI-SPION was about 45 nm. When PEI-SPION and pDNA encoding Oct 4 (pDNA-Oct 4) were mixed at the mass ratio of 1: 1, the hydrodynamic diameter (299.10 ± 5.01 nm) of conjugate complex was significantly smaller than that of complex at the mass ratio of 1: 2 (469.23 ± 28.86 nm; P 0.05), and similar results were found for treatments of nystatin. Compared with control group, 2-deoxy-D-glucose (2-DG) and amiloride could significantly decrease the transfection efficiency (P

Chicken embryonic stem cells (cESCs) isolated from the egg at the stage X hold great promise for cell therapy, tissue engineering, pharmaceutical, and biotechnological applications. They are considered to be pluripotent cells with the capacity to self-renewal and differentiate into specialized cells. However, long-term maintenance of cESCs cannot be realized now, which impedes the establishment of cESC line and limits their applications. Therefore, the separation locations, isolation methods, and culture conditions especially the supplements and action mechanisms of cytokines, including leukemia inhibitory factor, fibroblast growth factor, transforming growth factor beta, bone morphogenic protein, and activin for cESCs

To improve the isolation efficiency of parthenogenetic embryonic stem cells (pESCs) in mice, it is necessary to optimize the method to increase

In a previous study we investigated the association between two single nucleotide polymorphism (SNP) genotypes, namely steroid 17-alpha-hydroxylase/17,20 lyase (CYP17) SNP628 and dopamine receptor D2 (DRD2) SNP939, with two temperaments (calm and nervous) in Australian Merino sheep and concluded that the DRD2 SNP939 T/T genotype combined with the CYP17 SNP628 G/G genotype is associated with a calm temperament and could be used as a potential marker for calm sheep, whereas the DRD2 SNP939C allele combined with the CYP17 SNP628 A/A genotype is associated with a nervous temperament and could be used as a potential marker for nervous sheep. In sheep, the association between temperament and reproductive performance has been determined, but the association of these two SNP genotypes with sheep reproduction has not been investigated. Therefore, using Chinese Sinkiang Merino sheep, the present study investigated the association of the two CYP17 SNP628 and DRD2 SNP939 genotypes with sheep reproductive performance. Sheep with the DRD2 SNP939 T/T genotype combined with the CYP17 SNP628 G/G genotype had a higher ovulation rate, multiple gestation rate, better maternal behaviour and lower lamb mortality. Thus, the results of this study contribute to our knowledge of the association between genotypes and reproduction in sheep, which is beneficial for sheep genetics and breeding.

Somatic cell nuclear transfer (SCNT) is a powerful tool that is being applied in a variety of fields as diverse as the cloning and production of transgenic animals, rescue of endangered species and regenerative medicine. However, cloning efficiency is still very low and SCNT embryos generally show poor developmental competency and many abnormalities. The low efficiency is probably due to incomplete reprogramming of the donor nucleus and most of the developmental problems are thought to be caused by epigenetic defects. Applications of SCNT will, therefore, depend on improvements in the efficiency of production of healthy clones. This review has summarised the progress and strategies that have been used to make improvements in various animal species, especially over the period 2010–2017, including strategies based on histone modification, embryo aggregation and mitochondrial function. There has been considerable investiagation into the mechanisms that underpin each strategy, helping us better understand the nature of genomic reprogramming and nucleus–cytoplasm interactions.