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93.
Excessive and unresolved neuroinflammation is a key component of the pathological cascade in brain injuries such as ischemic stroke. Tripartite motif-containing 45 (TRIM45) is a ubiquitin E3 ligase involved in various critical biological processes. However, the role of TRIM45 in cerebral ischemia remains unknown. Here, we found that the TRIM45 protein was highly expressed in the peri-infarct areas of mice subjected to cerebral ischemia and reperfusion injury induced by middle cerebral artery occlusion. This study systemically evaluated the putative role of TRIM45 in the regulation of neuroinflammation during ischemic injury and the potential underlying mechanisms. We found that TRIM45 knockdown significantly decreased proinflammatory cytokine and chemokine production in primary cultured microglia challenged with oxygen-glucose deprivation and reoxygenation (OGD/R) treatment. Mechanistically, we demonstrated that TRIM45 constitutively interacted with TAB2 and consequently facilitated the Lys-63-linked polyubiquitination of TAB2, leading to the formation of the TAB1–TAK1–TAB2 complex and activation of TAK1, which was ultimately followed by activation of the nuclear factor-kappa B (NF-κB) signaling pathway. In an in vitro coculture Transwell system, downregulation of TRIM45 expression also inhibited the OGD/R-induced activation of microglia and alleviated neuronal apoptosis. More importantly, microglia-specific knockdown of TRIM45 in mice significantly reduced the infarct size, mitigated neurological deficit scores, and improved cognitive function after ischemic stroke. Taken together, our study reveals that the TRIM45–TAB2 axis is a crucial checkpoint that controls NF-κB signaling in microglia during cerebral ischemia and reperfusion injury. Therefore, targeting TRIM45 may be an attractive therapeutic strategy.Subject terms: Cell death in the nervous system, Stroke 相似文献
94.
采用水热法以FeCl2和KOH为原料制备Fe3 O4粉体,以氧化钇、氧化铕和氧化铽为原料制备Y2 O3:1;Eu3+,5;Tb3+粉体,然后以Fe3 O4粉体,Y2 O3:1;Eu3+,5;Tb3+粉体和三聚氰胺为原料,采用微波烧结法在Ar气气氛下制备FeYO3/Y2 O3:1;Eu3+,5;Tb3+复合粉体,利用XRD衍射仪对各种粉体的结构进行分析,利用扫描电镜对复合粉体的形貌进行观察,并利用振动样品磁强计对复合粉体的磁学性能进行研究.结果表明:复合粉体均呈针状,长度和细度均为纳米级.当Fe3 O4,Y2 O3:1;Eu3+,5;Tb3+和三聚氰胺比例为1:3:4时,所制备的FeYO3/Y2 O3:1;Eu3+,5;Tb3+粉体磁力最强,磁力饱和强度为11.3 emu·g-1. 相似文献
95.
运用浸渍吸附法制备了纳米级单分散Ag-SiO2无机复合抗菌材料,结合响应曲面方法,考察了Ag+浓度、反应时间和氨水添加量等因素对材料抗菌率的影响,考虑到材料制备成本,变色控制等多方面因素,选取了最优制备条件,实验结果表明:Ag+浓度为5.9×10-4 mol·L-1,氨水添加量为4.1 mL,反应时间为5.2 h时,材料有最佳的经济效益和抗菌性能,抗菌率达到91.7;.通过TEM、XRD、ICP和BET方法对材料的结构进行表征,结果表明:载体SiO2微球为无定形态;Ag-SiO2抗菌材料微球具有良好的分散性和稳定性,粒径尺寸均匀;Ag+成功负载于SiO2微球表面,负载量为8.10 mg·kg-1. 相似文献
96.
得到了广义次指数密度的两个新的等价条件,刻划了它们的卷积封闭性和卷积根封闭性. 相似文献
97.
Md. Mominur Rahman Md. Rezaul Islam Sheikh Shohag Md. Emon Hossain Md. Saidur Rahaman Fahadul Islam Muniruddin Ahmed Saikat Mitra Mayeen Uddin Khandaker Abubakr M. Idris Kumarappan Chidambaram Talha Bin Emran Simona Cavalu 《Molecules (Basel, Switzerland)》2022,27(5)
Obesity and diabetes are the most demanding health problems today, and their prevalence, as well as comorbidities, is on the rise all over the world. As time goes on, both are becoming big issues that have a big impact on people’s lives. Diabetes is a metabolic and endocrine illness set apart by hyperglycemia and glucose narrow-mindedness because of insulin opposition. Heftiness is a typical, complex, and developing overall wellbeing worry that has for quite some time been connected to significant medical issues in individuals, all things considered. Because of the wide variety and low adverse effects, herbal products are an important hotspot for drug development. Synthetic compounds are not structurally diverse and lack drug-likeness properties. Thus, it is basic to keep on exploring herbal products as possible wellsprings of novel drugs. We conducted this review of the literature by searching Scopus, Science Direct, Elsevier, PubMed, and Web of Science databases. From 1990 until October 2021, research reports, review articles, and original research articles in English are presented. It provides top to bottom data and an examination of plant-inferred compounds that might be utilized against heftiness or potentially hostile to diabetes treatments. Our expanded comprehension of the systems of activity of phytogenic compounds, as an extra examination, could prompt the advancement of remedial methodologies for metabolic diseases. In clinical trials, a huge number of these food kinds or restorative plants, as well as their bioactive compounds, have been shown to be beneficial in the treatment of obesity. 相似文献
98.
Over the last several years, the number of concepts and technologies enabling the production of environmentally friendly products (including materials, consumables, and services) has expanded. One of these ways is cradle-to-cradle (C2C) certifiedTM. Life cycle assessment (LCA) technique is used to highlight the advantages of C2C and recycling as a method for reducing plastic pollution and fossil depletion by indicating the research limitations and gaps from an environmental perspective. Also, it estimates the resources requirements and focuses on sound products and processes. The C2C life cycle measurements for petroleum-based poly (ethylene terephthalate) (PET) bottles, with an emphasis on different end-of-life options for recycling, were taken for mainland China, in brief. It is considered that the product is manufactured through the extraction of crude oil into ethylene glycol and terephthalic acid. The CML analysis method was used in the LCIA for the selected midpoint impact categories. LCA of the product has shown a drastic aftermath in terms of environmental impacts and energy use. But the estimation of these consequences is always dependent on the system and boundary conditions that were evaluated throughout the study. The impacts that burden the environment are with the extraction of raw material, resin, and final product production. Minor influences occurred due to the waste recycling process. This suggests that waste degradation is the key process to reduce the environmental impacts of the production systems. Lowering a product’s environmental impact can be accomplished in a number of ways, including reducing the amount of materials used or choosing materials with a minimal environmental impact during manufacture processes. 相似文献
99.
Dzyaloshinskii-Moriya(DM)相互作用驱动的矢量自旋手征态,能和声子发生耦合,具备非常丰富的物理现象.本论文以一维反铁磁链中自旋手征-声子耦合模型为基础,研究不同声子环境下,耦合强度对自旋手征动力学演化过程的影响规律.结果表明,对自旋S=1/2的系统,在不同的声子浴(sub-Ohmic(0 1))中,均会在非相干到相干自旋涨落过程中产生无能隙一级相变,其来源是自旋手征束缚态的形成.相变发生的临界自旋-声子耦合强度正比于自旋涨落大小,反比于系统德拜频率.当自旋-声子耦合强度超过其临界值时,自旋手征束缚态的产生将极大地抑制非相干自旋涨落. 相似文献
100.
Lin Wang Heqing Yang Hua Zhao Ru Yu Shi Liu Bao Bin Liu 《Applied Physics A: Materials Science & Processing》2011,102(1):61-68
The present work reports on novel four-layer thermally driven piezoresistive cantilevers implemented in one- and two-dimensional
arrays for parallel proximity scanning. There, the heater (metallic meander), the piezoresistive deflection sensor, and the
metal actuation film with significantly higher thermal expansion coefficient make up separate layers. Actuation efficiency
and cross-talk of the novel cantilever design are studied and compared with two recent designs: thin metallic film and ion-implanted
heater. The novel actuator, integrated on a 240 μm long and 3 μm thick silicon cantilever and supplied by V
dc=1 V enables deflections up to 5 μm of the AFM-tip with an actuation efficiency of about 170 nm/mW and suppressed cross-talk
between actuator and sensor. 相似文献