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991.
Kimiko HONSHO Michiko HIROSE Masanori HATORI Lubna YASMIN Haruna IZU Shogo MATOBA Sumie TOGAYACHI Hiroyuki MIYOSHI Tadashi SANKAI Atsuo OGURA Arata HONDA 《The Journal of reproduction and development》2015,61(1):13-19
Quality evaluation of pluripotent stem cells using appropriate animal models needs to be improved for human regenerative medicine. Previously, we demonstrated that although the in vitro neural differentiating capacity of rabbit induced pluripotent stem cells (iPSCs) can be mitigated by improving their baseline level of pluripotency, i.e., by converting them into the so-called “naïve-like” state, the effect after such conversion of rabbit embryonic stem cells (ESCs) remains to be elucidated. Here we found that naïve-like conversion enhanced the differences in innate in vitro differentiation capacity between ESCs and iPSCs. Naïve-like rabbit ESCs exhibited several features indicating pluripotency, including the capacity for teratoma formation. They differentiated into mature oligodendrocytes much more effectively (3.3–7.2 times) than naïve-like iPSCs. This suggests an inherent variation in differentiation potential in
vitro among PSC lines. When naïve-like ESCs were injected into preimplantation rabbit embryos, although they contributed efficiently to forming the inner cell mass of blastocysts, no chimeric pups were obtained. Thus, in vitro neural differentiation following naïve-like conversion is a promising option for determining the quality of PSCs without the need to demonstrate chimeric contribution. These results provide an opportunity to evaluate which pluripotent stem cells or treatments are best suited for therapeutic use. 相似文献
992.
Chunqiang WANG Chunjing LI Hongjiao LI Wei MA Shuxiong CHEN Yun ZHAO Jiahui RAO Xu ZHOU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1419-1425
Inhibins, as members of the transforming growth factor beta (TGF-β)
superfamily, downregulate the synthesis and secretion of follicle-stimulating hormone
(FSH) in an endocrine manner. The role of inhibin/betaglycan in the ovary regulation
recently gained attention. To date, no data exist on the function of inhibin α subunit and
betaglycan in cystic follicles. In this study, the expressions of inhibin α subunit and
betaglycan in cystic follicles were investigated using immunohistochemistry, real-time PCR
and Western blot analysis. Both inhibin α subunit and betaglycan immunoreactivities were
mainly localized in the granulosa cells of follicles. Expression of inhibin α subunit and
betaglycan was inferior in cystic follicles compared with that in normal large follicles.
However, the result of enzyme-linked immunosorbent assay showed no significant difference
in the decreasing in concentration of inhibin α subunit in cystic follicular fluid
compared with the control (P>0.05). In this study, we explored the
effects of FSH on betaglycan expression in granulosa cells in vitro. As
expected, a significant increase in the expressions of betaglycan mRNA and protein in
granulosa cells was observed in response to exogenous FSH (30
ng/ml) (P<0.05) compared with the
control. Consequently, this study provides evidence that the expressions of inhibin α
subunit and betaglycan are inferior in cystic follicles, and this may be caused by the
decrease in FSH in the presence of a cystic follicle. 相似文献
993.
994.
Mohamed M’BAYE Guohua HUA Hamid Ali KHAN Liguo YANG 《The Journal of reproduction and development》2015,61(5):391-397
Inhibins are members of the TGFβ superfamily and act as suppressors
of follicle stimulating hormone (FSH) secretion from pituitary glands
via a negative feedback mechanism to regulate folliculogenesis. In
this study, the INHBB gene was knocked down by three
RNAi-Ready pSIREN-RetroQ-ZsGreen vector- mediated recombinant plasmids
to explore the effects of INHBB silencing on
granulosa cell (GC) cell cycle, apoptosis and steroid production
in vitro. Quantitative real-time polymerase chain
reaction, Western blot, flow cytometry and ELISA were performed to
evaluate the role of INHBB in the mouse GC cell
cycle, apoptosis and steroid production in vitro. The
results showed that the relative mRNA and protein expression of
INHBB in mouse GCs can be significantly reduced by
RNAi with pshRNA-B1, pshRNA-B2 and pshRNA-B3 plasmids, with pshRNA-B3
having the best knockdown efficiency. Downregulation of the expression
of INHBB significantly arrests cells in the G1 phase
of the cell cycle and increases the apoptosis rate in GCs. This was
further confirmed by downregulation of the protein expressions of
Cyclin D1, Cyclin E and Bcl2, while the protein expression of Bax was
upregulated. In addition, specific downregulation of
INHBB markedly decreased the concentration of
estradiol and progesterone, which was further validated by the
decrease in the mRNA levels of CYP19A1and
CYP11A1. These findings suggest that inhibin βB is
important in the regulation of apoptosis and cell cycle progression in
granulosa cells. Furthermore, the inhibin βB subunit has a role in the
regulation of steroid hormone biosynthesis. Evidence is accumulating
to support the concept that inhibin βB is physiologically essential
for early folliculogenesis in the mouse. 相似文献
995.
Zhi-qiang Li Dan Gui Zhi-hua Sun Jun-bo Zhang Wen-zhi Zhang Hui Zhang Fei Guo Chuang-fu Chen 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):467-473
Brucellosis is a zoonotic disease that causes animal and human diseases. Vaccination is a major measure for prevention of brucellosis, but it is currently not possible to distinguish vaccinated animals from those that have been naturally infected. Therefore, in this study, we constructed the Brucella (B.) abortus 2380 wbkA mutant (2308ΔwbkA) and evaluated its virulence. The survival of 2308ΔwbkA was attenuated in murine macrophage (RAW 264.7) and BALB/c mice, and it induced high protective immunity in mice. The wbkA mutant elicited an anti-Brucella-specific immunoglobulin G response and induced the secretion of gamma interferon. Antibodies to 2308ΔwbkA could be detected in sera from mice, implying the potential for use of this protein as a diagnostic antigen. The WbkA antigen would allow serological differentiation between infected and vaccinated animals. These results suggest that 2308ΔwbkA is a potential attenuated vaccine against 16M. This vaccine will be further evaluated in sheep. 相似文献
996.
BettyPriorinrosegenus,rosebolyis-onevarietyofFlonbondaROse.ItisoneOfmodernChineserose,withcoldresistanceandagmnstpestcharactenshcsChineserosecuttase1soutOfquestionintemPeratezoneandtothe6outhoftethperat6zone,butthereexistmanyqueshonsinHarbnareawhichbelongstonortherntemperat6zonebecauseofshortergrOwingseasonandlowerairtemperatUreinautUmnandwintertmaincuttageseasonsof8ettyPnor).Theexpen-mentonwatercuthngPropagahonofBettyPnorwasconductedlnordertointroducethesspeciesintoHarbin.MThan^LSAun… 相似文献
997.
998.
云南玉溪市老城中心面临着传统商业衰退以及城市化进程中对中心商业区升级的矛盾,通过引入城市网络的概念,将原本集中布置的商业区延展为一个连续的商业网络,并设计穿越整个地块的开放绿地空间,将保留的历史建筑融合在绿地网络之中,以此保持和发展该地区原有的文化和经济氛围,并形成多元化的土地利用方式。 相似文献
999.
指出了防治面源污染是保护水源地的重要措施。对引江济汉工程起始段面源污染现状进行了调查分析,结果表明:引江济汉工程运行后,农田面积减少了40%,其中部分农田改为蔬菜等经济作物用地;化肥使用总量下降了41.7%,农药的使用总量也呈相同趋势下降,但农用地的平均化肥、农药使用量未发生显著变化,工程前后基本持平;区内水渠、沟渠阻塞严重,配套基础水利设施匮乏,灌溉条件差,地表径流与灌溉用水任意流失,面源污染的潜在威胁大,急需采取有针对性的治理措施。有针对性地提出了面源污染防治对策建议。 相似文献
1000.
A simplified water balance model in conjunc-tion with an evapotranspiration (ET) model and cumulative forest cover data were used to quantify the changes in annual water yield in response to reforestat... 相似文献