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Chunxiao Qi Xiangsheng Liu Dengke Zhi Yifan Tai Yufei Liu Qiqi Sun Kai Wang Shufang Wang Adam C.Midgley Deling Kong 《Nano Research》2022,(2):1680-1690
Translation of exosome-based therapies to pharmaceutical use is hindered by difficulties in large-scale and cost-effective production of clinical-grade exosomes.The rational design of nanovesicles that mimic the functionalities and physicochemical properties of exosomes may circumvent these issues.In this study,membranes and secretome from efficacy-potentiated mesenchymal stem cells(MSCs)were developed into size-controllable nanovesicles(Meseomes).MSCs were primed with interferon-y(IFNy)and tumor necrosis factor-a(TNFa),harvested,and exosome-mimicking Meseomes were subsequently synthesized via one-step extrusion.Meseomes demonstrated significant enhancement of pro-angiogenic,pro-proliferative,antiinflammatory,and anti-fibrotic effects on endothelial cells,macrophages,and hepatic stellate cells in vitro.Meseomes from primed MSCs benefited from an enrichment of bioactive and therapeutic molecules compared to nanovesicles from unprimed MSCs,as validated by liquid chromatography-mass spectrometry(LC-MS)proteomic analysis.Systemic administration of Meseomes to acute liver injury models resulted in the recovery of liver function,attenuated tissue necrosis.Further assessment of locally administered Meseomes in acute hindlimb ischemia models resulted in the salvage of the majority of the ischemic hindlimb(>80%),which was due to enhanced angiogenesis and M2 macrophage polarization.The versatility and therapeutic efficacy of our developed acellular Meseomes offer an appealing alternative to traditional cell or exosome therapies for regenerative and translational medicine. 相似文献
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由于传统散射矩阵法(scattering matrix method, SMM)在计算过程中会产生奇异矩阵,本文基于改进的SMM (improved SMM, ISMM)结合一维磁化等离子体湍流模型,计算了等离子体湍流介质对电磁波在不同入射角下的反射系数和透射系数,同时分析了电磁波在非均匀磁化等离子体中的传播特性。结果表明,湍流的出现极大地影响了等离子体鞘套中电子的运动规律,使其运动过程中能量衰减增多,因此其在0~35 GHz的透射系数增大;另一方面外部磁场的增大,对左旋圆极化波与右旋圆极化波的传播特性影响相反,这是因为在左旋情况下,左旋圆极化波的旋转方向正好与电子的旋转方向相同,右旋圆极化波相反;随着入射角度的增大,相当于电磁波在等离子体湍流中的传播距离增大,导致更多的电磁波能量被吸收;此外,考虑非均匀磁化情况后,电磁波在0~35 GHz频段内的右旋圆极化的透射系数更大。这些结果为研究电磁波在非均匀磁化等离子体湍流介质的传播特性提供了理论依据。
相似文献55.
针对清扫机器人在停车场结构化路面下存在的加速度过大、路径偏离全局路径过大等问题,提出了一种改进的动态窗口法(DWA).首先,为了限制小车加速度的范围,对DWA速度空间的动力学约束进行优化,避免出现过大的加速度导致轮胎垂直载荷过小的状况.然后,基于激光里程计对轨迹推算环节进行实时误差补偿,解决停车场路面下路径偏离全局路径较大的问题.最后将改进的DWA应用于四轮独立驱动、独立转向的清扫机器人上进行对比实验.实验结果表明,在相同的全局路径、相同的路况下,改进DWA的路径平均误差较传统DWA减小了约60%,轮胎垂直载荷在不同路况下也大大提高,验证了本文方法的有效性和可靠性. 相似文献
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Zhi He Li Zheng Qiqi Chen Sen Xiong Zhide He Jiaxiang Hu Zhijun Ma Qian Zhang Jiayang He Lijuan Ye Liang He Jie Luo Xiaobin Gu Mingwang Zhang Ziting Tang Yuanyuan Jiao Yong Pu Jinxin Xiong Kuo Gao Bolin Lai Shiyong Yang Deying Yang Taiming Yan 《International journal of molecular sciences》2022,23(23)
Bmpr2 plays a central role in the regulation of reproductive development in mammals, but its role during ovarian development in fish is still unclear. To ascertain the function of bmpr2 in ovarian development in the ricefield eel, we isolated and characterized the bmpr2 cDNA sequence; the localization of Bmpr2 protein was determined by immunohistochemical staining; and the expression patterns of bmpr2 in ovarian tissue incubated with FSH and hCG in vitro were analyzed. The full-length bmpr2 cDNA was 3311 bp, with 1061 amino acids encoded. Compared to other tissues, bmpr2 was abundantly expressed in the ovary and highly expressed in the early yolk accumulation (EV) stages of the ovary. In addition, a positive signal for Bmpr2 was detected in the cytoplasm of oocytes in primary growth (PG) and EV stages. In vitro, the expression level of gdf9, the ligand of bmpr2, in the 10 ng/mL FSH treatment group was significantly higher after incubation for 4 h than after incubation for different durations. However, bmpr2 expression in the 10 ng/mL FSH treatment group at 2 h, 4 h and 10 h was significantly lower. Importantly, the expression level of bmpr2 and gdf9 in the 100 IU/mL hCG group had similar changes that were significantly decreased at 4 h and 10 h. In summary, Bmpr2 might play a pivotal role in ovarian growth in the ricefield eel, and these results provide a better understanding of the function of bmpr2 in ovarian development and the basic data for further exploration of the regulatory mechanism of gdf9 in oocyte development. 相似文献
57.
Zhi He Qiqi Chen Liang He Jinxin Xiong Kuo Gao Bolin Lai Li Zheng Yong Pu Yuanyuan Jiao Zhijun Ma Ziting Tang Mingwang Zhang Deying Yang Taiming Yan 《International journal of molecular sciences》2022,23(18)
Apoptosis plays a key role in the effective removal of excessive and defective germ cells, which is essential for sequential hermaphroditism and sex change in vertebrates. The ricefield eel, Monopterus albus is a protogynous hermaphroditic fish that undergoes a sequential sex change from female to male. Previous studies have demonstrated that apoptosis is involved in sex change in M. albus. However, the apoptotic signaling pathway is unclear. In the current study, we explored the underlying mechanism of apoptosis during gonadal development and focused on the role of the mitochondrial apoptosis signaling pathway in sex change in M. albus. Flow cytometry was performed to detect apoptosis in gonads at five sexual stages and ovary tissues exposed to hydrogen peroxide (H2O2) in vitro. Then the expression patterns of key genes and proteins in the mitochondrial pathway, death receptor pathway and endoplasmic reticulum (ER) pathway were examined. The results showed that the apoptosis rate was significantly increased in the early intersexual stage and then decreased with the natural sex change from female to male. Quantitative real-time PCR revealed that bax, tnfr1, and calpain were mainly expressed in the five stages. ELISA demonstrated that the relative content of cytochrome-c (cyt-c) in the mitochondrial pathway was significantly higher than that of caspase8 and caspase12, with a peak in the early intersexual stage, while the levels of caspase8 and caspase12 peaked in the late intersexual stage. Interestingly, the Pearson’s coefficient between cyt-c and the apoptosis rate was 0.705, which suggests that these factors are closely related during the gonadal development of M. albus. Furthermore, the cyt-c signal was found to be increased in the intersexual stage by immunohistochemistry. After incubation with H2O2, the mRNA expression of mitochondrial pathway molecules such as bax, apaf-1, and caspase3 increased in ovary tissues. In conclusion, the present results suggest that the mitochondrial apoptotic pathway may play a more important role than the other apoptotic pathways in sex change in M. albus. 相似文献
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目的 对上海市浦东新区一起食物中毒事件进行病原检测和溯源分析,为此类事件的处置和判定提供依据。方法 对病例和从业人员肛拭子以及留样食品样品进行病原分离和鉴定;对分离株进行肠毒素检测、药物敏感性试验、脉冲场凝胶电泳(PFGE)和多位点序列分型(MLST)分子分型和溯源。结果 从9份病例肛拭子、1份从业人员肛拭子及3份留样食品样品中分离到13株金黄色葡萄球菌。10株人源分离株产A型和E型肠毒素,3株食源分离株产A型、D型和E型肠毒素。13株分离株均对青霉素耐药,PFGE条带相似度为100%,MLST分型均为ST6型。结论 本起事件是由金黄色葡萄球菌污染引起的食物中毒事件,需要进一步加强对食品加工企业、食堂等的宣传教育和管理,防止类似事件的发生。 相似文献