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921.
922.
Chunlei Miao Dengke Qin Peigang Cao Ping Lu Yutong Xia Mengjiao Li Miao Sun Wei Zhang Fanghong Yang Yingjie Zhang Shengjian Tang Tianyi Liu Fangjun Liu 《Journal of cellular biochemistry》2019,120(5):8754-8763
Bone morphogenetic protein (BMP)2/7 heterodimer shows greater efficacy in enhancing bone regeneration. However, the precise mechanism and the role of mitogen-activated protein kinase (MAPK) signaling network in BMP2/7-driven osteogenesis remain ambiguous. In this study, we evaluated the effects of BMP2/7 heterodimers on osteoblastic differentiation in rat bone marrow mesenchymal stem cells (BMSCs), with the aim to elaborate how MAPKs might be involved in this cellular process by treatment of rat BMSCs with BMP2/-7 with a special signal-pathway inhibitor. We found that BMP2/7 heterodimer induced a much stronger osteogenic response in rat BMSCs compared with either homodimer. Most interestingly, extracellular signal-regulated kinase (ERK) demonstrated a highly sustained phosphorylation and activation in the BMP2/7 heterodimer treatment groups, and inhibition of ERK cascades using U0126 special inhibitor that significantly reduced the activity of ALP and calcium mineralization to a substantial degree in rat BMSCs treated with BMP2/7 heterodimers. Collectively, we demonstrate that BMP2/7 heterodimer shows a potent ability to stimulate osteogenesis in rat BMSCs. The activated ERK signaling pathway involved in this process may contribute partially to an increased osteogenic potency of heterodimeric BMP2/7 growth factors. 相似文献
923.
Multiple studies have reported different methods in treating gestational diabetes mellitus (GDM); however, the relationship between miR-335-5p and GDM still remains unclear. Here, this study explores the effect of miR-335-5p on insulin resistance and pancreatic islet β-cell secretion via activation of the TGFβ signaling pathway by downregulating VASH1 expression in GDM mice. The GDM mouse model was established and mainly treated with miR-335-5p mimic, miR-335-5p inhibitor, si-VASH1, and miR-335-5p inhibitor + si-VASH1. Oral glucose tolerance test (OGTT) was conducted to detect fasting blood glucose (FBG) fasting insulin (FINS). The OGTT was also used to calculate a homeostasis model assessment of insulin resistance (HOMA-IR). A hyperglycemic clamp was performed to measure the glucose infusion rate (GIR), which estimated β-cell function. Expressions of miR-335-5p, VASH1, TGF-β1, and c-Myc in pancreatic islet β-cells were determined by RT-qPCR, western blot analysis, and insulin release by ELISA. The miR-335-5p mimic and si-VASH1 groups showed elevated blood glucose levels, glucose area under the curve (GAUC), and HOMA-IR, but a reduced GIR and positive expression of VASH1. Overexpression of miR-335-5p and inhibition of VASH1 contributed to activated TGFβ1 pathway, higher c-Myc, and lower VASH1 expressions, in addition to downregulated insulin and insulin release levels. These findings provided evidence that miR-335-5p enhanced insulin resistance and suppressed pancreatic islet β-cell secretion by inhibiting VASH1, eventually activating the TGF-β pathway in GDM mice, which provides more clinical insight on the GDM treatment. 相似文献
924.
为优化家蚕杆状病毒表达系统,提高外源基因的表达产量。文中通过同源重组技术,用串联的氯霉素基因(Cm)表达盒和绿色荧光蛋白基因(egfp)表达盒将其替换,从而获得Chitinase和Cystein Protease两个基因缺失的家蚕杆状病毒载体。通过转座,将多角体启动子控制的家蚕二分浓核病毒(Bm BDV)ns1基因表达盒,定点插入到改造后的该分子载体中。将重组载体转染Bm N细胞,获得能表达家蚕二分浓核病毒(Bm BDV)NS1的缺失型重组病毒;另外,将多角体启动子控制的ns1基因转座到野生型Bm-bacmid中,获得能表达Bm BDV NS1的野生型重组病毒。将这两种病毒分别皮下注射家蚕,对感染后的家蚕血液中NS1表达水平进行比较,发现缺失Chitinase和Cystein Protease重组病毒感染的家蚕血液中,NS1的表达量是对照组的3倍,从而建立了一种高效表达可溶性NS1蛋白的方法,为靶蛋白的结构与功能研究奠定基础。 相似文献
925.
Use of random forest in FTIR analysis of LDL cholesterol and tri‐glycerides for hyperlipidemia 下载免费PDF全文
A quantitative determination method for the diagnosis of hyperlipidemia was developed using Fourier transform infrared (FTIR) spectroscopy. Random forest (RF) was demonstrated as a potential multivariate algorithm for the FTIR analysis of low‐density lipoprotein cholesterol (LDL‐C) and tri‐glycerides (TG) in human serum samples. The informative wavebands for LDL‐C and TG were selected based on the Gini importance. The selected wavebands were mainly within the fingerprint region. The RF modeling results were better than those derived using PLS in validation process, because the chance for over‐fitting was possibly eliminated in RF algorithm. ARF also demonstrated favorable results in the test process. The prospective model exhibited a higher than 90% true prediction in negative/positive properties for male and female samples. These clinical statistical results indicated the optimization of RF algorithm performed accurately in the FTIR determination of LDL‐C and TG. RF is evaluated as a promising tool for diagnosing and controlling hyperlipidemia in populations. The parameter optimization methodology is useful in the improving model accuracy using FTIR spectroscopic technology. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1693–1702, 2015 相似文献
926.
927.
928.
火炬松成熟合子胚培养直接器官发生和植株再生 总被引:11,自引:0,他引:11
基因型Hb,Ma和Mc的火炬松成熟合子胚在附加1.0mg/LNAA,4.0mg/LBA,500mg/LLH和500mg/L谷氨酰胺的TE培养基上培养12周后,在子叶和胚轴部位形成不定芽原基。然后将合子胚转移到附加0.5mg//LNAA,0.05mg/LIBA,2mg/LBA,500mg/LLH和500mg/L谷氨酰胺的TE不定芽分化培养基上,6周后分化产生大量不定芽,3种基因型中,Hb的直接不定芽 相似文献
929.
为探讨金属硫蛋白(MT)在运动提高机体自我贩作用,本文实验观察了游泳运动对大鼠心、肝、肺、脑、血管、因浆和骨骼肌等组织金属硫蛋白含量的影响。结果表明耐力训练组大鼠心、肝、肺和骨骼组织金属硫蛋白含量较政党对照组明显降低13-34%(P〈0.05);急性力竭运动组大鼠心、肝、脑、肺和骨骼肌组织其含量较正常对照则明显或高21-75%(P〈0.05);但两组大鼠血管和血浆MT含量变化与对照组大鼠要比无统计 相似文献
930.
国家公园规划制度功能定位与空间属性 总被引:1,自引:0,他引:1
我国将构建统一的国土空间规划体系, 整体谋划国土空间开发保护格局, 强化对各类专项规划的指导约束, 这必将对国家公园保护制度产生重大影响。本文分析了国土空间规划视角下国家公园规划制度的定位, 阐述了国家公园规划承载空间规划与发展规划两大体系的基本属性, 应在国土空间规划体系中具有优先权和前置权; 重点分析了各国家公园总体规划在国家规划体系中的功能与属性特征, 作为空间规划应承接好上位空间规划对国家公园的控制指标和管控要求, 作为建设规划应承接好上位或同域国民经济发展规划等对国家公园的目标任务要求, 作为管理规划要明确国家公园顺畅运行的要求。国家公园应在分区规划、控制性详细规划等专项规划方面寻求创新, 探索国家公园用途管制的实现模式。 相似文献