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111.
Tao Jiang Hao Pang Jie An Pinjing Lu Yawei Feng Xi Liang Wei Zhong Zhong Lin Wang 《Liver Transplantation》2020,10(23)
Ocean wave energy is a promising renewable energy source, but harvesting such irregular, “random,” and mostly ultra‐low frequency energies is rather challenging due to technological limitations. Triboelectric nanogenerators (TENGs) provide a potential efficient technology for scavenging ocean wave energy. Here, a robust swing‐structured triboelectric nanogenerator (SS‐TENG) with high energy conversion efficiency for ultra‐low frequency water wave energy harvesting is reported. The swing structure inside the cylindrical TENG greatly elongates its operation time, accompanied with multiplied output frequency. The design of the air gap and flexible dielectric brushes enable mininized frictional resistance and sustainable triboelectric charges, leading to enhanced robustness and durability. The TENG performance is controlled by external triggering conditions, with a long swing time of 88 s and a high energy conversion efficiency, as well as undiminished performance after continuous triggering for 4 00 000 cycles. Furthermore, the SS‐TENG is demonstrated to effectively harvest water wave energy. Portable electronic devices are successfully powered for self‐powered sensing and environment monitoring. Due to the excellent performance of the distinctive mechanism and structure, the SS‐TENG in this work provides a good candidate for harvesting blue energy on a large scale. 相似文献
112.
目的:研究加味八珍汤联合股骨近端防旋髓内钉(Proximal Femoral Nail Antirotation,PFNA)对老年股骨转子间骨折患者的临床效果及对术后隐性失血和血液流变学的影响。方法:选择2014年3月至2017年3月我院收治的68例接受PFNA治疗的转子间骨折者,将其随机平均分为观察组(34例,术后口服加味八珍汤颗粒7天)、对照组(34例)。对比两组总失血量、隐性失血量、隐性失血比例、血液流变学指标(血浆粘度及全血黏度低、中、高切)、不良反应等。结果:⑴两组各剔除2例,94.12%(64/68)的受试者完成研究。⑵两组总失血量相当,差异无统计学意义(P0.05);与对照组相比,观察组隐性失血量及隐性失血发生率均显著降低(P0.05)。⑶治疗前,两组血浆粘度及低、中、高切全血黏度比较差异无统计学意义(P0.05);治疗后,两组血浆粘度及低、中、高切全血黏度均显著低于本组治疗前(P0.05),且观察组以上指标均明显低于对照组(P0.05)。⑷观察组发生肌间静脉血栓1例,无药物过敏及毒副反应;对照组发生1例深静脉血栓、4例肌间静脉血栓。观察组不良反应率为3.125%,显著低于对照组(15.625%,P0.05)。结论:加味八珍汤既可显著减少老年股骨转子间骨折患者PFNA术后隐性失血,又能改善血流动力学、减少并发症。 相似文献
113.
Wang Xingyu Huang Kun Jiang Haini Hua Lijuan Yu Weiwei Ding Dan Wang Ke Li Xiaopan Zou Zhong Jin Meilin Xu Shuyun 《中国病毒学》2020,35(6):793-802
Virologica Sinica - COVID-19 patients can recover with a median SARS-CoV-2 clearance of 20 days post initial symptoms (PIS). However, we observed some COVID-19 patients with existing... 相似文献
114.
115.
Peijing Zheng Liyang Chen Suye Zhong Xiaobo Wei Qi Zhao Qinglin Pan Zhensheng Kang Jie Liu 《Environmental microbiology》2020,22(12):5309-5326
Plants quickly accumulate reactive oxygen species (ROS) to resist against pathogen invasion, while pathogens strive to escape host immune surveillance by degrading ROS. However, the nature of the strategies that fungal pathogens adopt to counteract host-derived oxidative stress is manifold and requires deep investigation. In this study, a superoxide dismutase (SOD) from Puccinia striiformis f. sp. tritici (Pst) PsSOD2 with a signal peptide (SP) and the glycophosphatidyl inositol (GPI) anchor, strongly induced during infection, was analysed for its biological characteristics and potential role in wheat–Pst interactions. The results showed that PsSOD2 encodes a Cu-only SOD and responded to ROS treatment. Heterologous complementation assays in Saccharomyces cerevisiae suggest that the SP of PsSOD2 is functional for its secretion. Transient expression in Nicotiana benthamiana leaves revealed that PsSOD2 is localized to the plasma membrane. In addition, knockdown of PsSOD2 by host-induced gene silencing reduced Pst virulence and resulted in restricted hyphal development and increased ROS accumulation. In contrast, heterologous transient assays of PsSOD2 suppressed flg22-elicited ROS production. Taken together, our data indicate that PsSOD2, as a virulence factor, was induced and localized to the plasma membrane where it may function to scavenge host-derived ROS for promoting fungal infection. 相似文献
116.
117.
Xiaodong Mu Chieh Tseng William S. Hambright Polina Matre Chih‐Yi Lin Palas Chanda Wanqun Chen Jianhua Gu Sudheer Ravuri Yan Cui Ling Zhong John P. Cooke Laura J. Niedernhofer Paul D. Robbins Johnny Huard 《Aging cell》2020,19(8)
Hutchinson–Gilford progeria syndrome (HGPS) is caused by the accumulation of mutant prelamin A (progerin) in the nuclear lamina, resulting in increased nuclear stiffness and abnormal nuclear architecture. Nuclear mechanics are tightly coupled to cytoskeletal mechanics via lamin A/C. However, the role of cytoskeletal/nuclear mechanical properties in mediating cellular senescence and the relationship between cytoskeletal stiffness, nuclear abnormalities, and senescent phenotypes remain largely unknown. Here, using muscle‐derived mesenchymal stromal/stem cells (MSCs) from the Zmpste24?/? (Z24?/?) mouse (a model for HGPS) and human HGPS fibroblasts, we investigated the mechanical mechanism of progerin‐induced cellular senescence, involving the role and interaction of mechanical sensors RhoA and Sun1/2 in regulating F‐actin cytoskeleton stiffness, nuclear blebbing, micronuclei formation, and the innate immune response. We observed that increased cytoskeletal stiffness and RhoA activation in progeria cells were directly coupled with increased nuclear blebbing, Sun2 expression, and micronuclei‐induced cGAS‐Sting activation, part of the innate immune response. Expression of constitutively active RhoA promoted, while the inhibition of RhoA/ROCK reduced cytoskeletal stiffness, Sun2 expression, the innate immune response, and cellular senescence. Silencing of Sun2 expression by siRNA also repressed RhoA activation, cytoskeletal stiffness and cellular senescence. Treatment of Zmpste24?/? mice with a RhoA inhibitor repressed cellular senescence and improved muscle regeneration. These results reveal novel mechanical roles and correlation of cytoskeletal/nuclear stiffness, RhoA, Sun2, and the innate immune response in promoting aging and cellular senescence in HGPS progeria. 相似文献
118.
119.
Gang Fan Mario Kaßmann Yingqiu Cui Claudia Matthaeus Sverine Kunz Cheng Zhong Shuai Zhu Yu Xie Dmitry Tsvetkov Oliver Daumke Yu Huang Maik Gollasch 《Aging cell》2020,19(4)
Caveolae position CaV3.2 (T‐type Ca2+ channel encoded by the α‐3.2 subunit) sufficiently close to RyR (ryanodine receptors) for extracellular Ca2+ influx to trigger Ca2+ sparks and large‐conductance Ca2+‐activated K+ channel feedback in vascular smooth muscle. We hypothesize that this mechanism of Ca2+ spark generation is affected by age. Using smooth muscle cells (VSMCs) from mouse mesenteric arteries, we found that both Cav3.2 channel inhibition by Ni2+ (50 µM) and caveolae disruption by methyl‐ß‐cyclodextrin or genetic abolition of Eps15 homology domain‐containing protein (EHD2) inhibited Ca2+ sparks in cells from young (4 months) but not old (12 months) mice. In accordance, expression of Cav3.2 channel was higher in mesenteric arteries from young than old mice. Similar effects were observed for caveolae density. Using SMAKO Cav1.2?/? mice, caffeine (RyR activator) and thapsigargin (Ca2+ transport ATPase inhibitor), we found that sufficient SR Ca2+ load is a prerequisite for the CaV3.2‐RyR axis to generate Ca2+ sparks. We identified a fraction of Ca2+ sparks in aged VSMCs, which is sensitive to the TRP channel blocker Gd3+ (100 µM), but insensitive to CaV1.2 and CaV3.2 channel blockade. Our data demonstrate that the VSMC CaV3.2‐RyR axis is down‐regulated by aging. This defective CaV3.2‐RyR coupling is counterbalanced by a Gd3+ sensitive Ca2+ pathway providing compensatory Ca2+ influx for triggering Ca2+ sparks in aged VSMCs. 相似文献
120.
Ming‐Yuan Du Jia‐Xi Duan Chen‐Yu Zhang Hui‐Hui Yang Xin‐Xin Guan Wen‐Jing Zhong Yan‐Zhe Liu Zi‐Ming Li Yu‐Rui Cheng Yong Zhou Cha‐Xiang Guan 《Cell biology international》2020,44(1):98-107
Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF in the inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reduced body weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM‐induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM‐induced expression of α‐smooth muscle actin at both the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor‐β1, interleukin‐1β, and tumor necrosis factor‐α in the lungs of BLM‐stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM‐induced murine model. 相似文献