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101.
Alzheimer's disease (AD), a severe age‐related neurodegenerative disorder, lacks effective therapeutic methods at present. Physical approaches such as gamma frequency light flicker that can effectively reduce amyloid load have been reported recently. Our previous research showed that a physical method named photobiomodulation (PBM) therapy rescues Aβ‐induced dendritic atrophy in vitro. However, it remains to be further investigated the mechanism by which PBM affects AD‐related multiple pathological features to improve learning and memory deficits. Here, we found that PBM attenuated Aβ‐induced synaptic dysfunction and neuronal death through MKP7‐dependent suppression of JNK3, a brain‐specific JNK isoform related to neurodegeneration. The results showed PBM‐attenuated amyloid load, AMPA receptor endocytosis, dendrite injury, and inflammatory responses, thereby rescuing memory deficits in APP/PS1 mice. We noted JNK3 phosphorylation was dramatically decreased after PBM treatment in vivo and in vitro. Mechanistically, PBM activated ERK, which subsequently phosphorylated and stabilized MKP7, resulting in JNK3 inactivation. Furthermore, activation of ERK/MKP7 signaling by PBM increased the level of AMPA receptor subunit GluR 1 phosphorylation and attenuated AMPA receptor endocytosis in an AD pathological model. Collectively, these data demonstrated that PBM has potential therapeutic value in reducing multiple pathological features associated with AD, which is achieved by regulating JNK3, thus providing a noninvasive, and drug‐free therapeutic strategy to impede AD progression.  相似文献   
102.
RIG-I and MDA5 are cytoplasmic RNA sensors that mediate cell intrinsic immunity against viral pathogens. While it has been well-established that RIG-I and MDA5 recognize RNA viruses, their interactive network with DNA viruses, including herpes simplex virus 1 (HSV-1), remains less clear. Using a combination of RNA-deep sequencing and genetic studies, we show that the γ134.5 gene product, a virus-encoded virulence factor, enables HSV growth by neutralization of RIG-I dependent restriction. When expressed in mammalian cells, HSV-1 γ134.5 targets RIG-I, which cripples cytosolic RNA sensing and subsequently suppresses antiviral gene expression. Rather than inhibition of RIG-I K63-linked ubiquitination, the γ134.5 protein precludes the assembly of RIG-I and cellular chaperone 14-3-3ε into an active complex for mitochondrial translocation. The γ134.5-mediated inhibition of RIG-I-14-3-3ε binding abrogates the access of RIG-I to mitochondrial antiviral-signaling protein (MAVS) and activation of interferon regulatory factor 3. As such, unlike wild type virus HSV-1, a recombinant HSV-1 in which γ134.5 is deleted elicits efficient cytokine induction and replicates poorly, while genetic ablation of RIG-I expression, but not of MDA5 expression, rescues viral growth. Collectively, these findings suggest that viral suppression of cytosolic RNA sensing is a key determinant in the evolutionary arms race of a large DNA virus and its host.  相似文献   
103.
Osteoarthritis (OA) is one of the most frequent chronic joint diseases with the increasing life expectancy. The main characteristics of the disease are loss of articular cartilage, subchondral bone sclerosis and synovium inflammation. Physical measures, drug therapy and surgery are the mainstay of treatments for OA, whereas drug therapies are mainly limited to analgesics, glucocorticoids, hyaluronic acids and some alternative therapies because of single therapeutic target of OA joints. Baicalein, a traditional Chinese medicine extracted from Scutellaria baicalensis Georgi, has been widely used in anti-inflammatory therapies. Previous studies revealed that baicalein could alleviate cartilage degeneration effectively by acting on articular chondrocytes. However, the mechanisms involved in baicalein-mediated protection of the OA are not completely understood in consideration of integrality of arthrosis. In this study, we found that intra-articular injection of baicalein ameliorated subchondral bone remodelling. Further studies showed that baicalein could decrease the number of differentiated osteoblasts by inhibiting pre-osteoblasts proliferation and promoting pre-osteoblasts apoptosis. In addition, baicalein impaired angiogenesis of endothelial cells and inhibited proliferation of synovial cells. Taken together, these results implicated that baicalein might be an effective medicine for treating OA by regulating multiple targets.  相似文献   
104.
Ai  Xiaopeng  Dong  Xing  Guo  Ying  Yang  Peng  Hou  Ya  Bai  Jinrong  Zhang  Sanyin  Wang  Xiaobo 《Purinergic signalling》2021,17(2):229-240

Adenosine triphosphate (ATP) and its metabolites adenosine diphosphate, adenosine monophosphate, and adenosine in purinergic signaling pathway play important roles in many diseases. Activation of P2 receptors (P2R) channels and subsequent membrane depolarization can induce accumulation of extracellular ATP, and furtherly cause kinds of diseases, such as pain- and immune-related diseases, cardiac dysfunction, and tumorigenesis. Active ingredients of traditional Chinese herbals which exhibit superior pharmacological activities on diversified P2R channels have been considered as an alternative strategy of disease treatment. Experimental evidence of potential ingredients in Chinese herbs targeting P2R and their pharmacological activities were outlined in the study.

  相似文献   
105.
A novel pH-activatable fluorescent probe, 1-(propan-2-yl)-9H-pyrido[3,4-b]indole-3-carboxylic acid ( L-1 ), based on β-carboline derivatives, has been developed, which displays significant fluorescent response toward pH variation with high selectivity, good photo-stability and favorable pKa value. Moreover, L-1 can dynamically monitor the release of protons during ester hydrolysis reaction in consistent with enzymatic kinetics manner.  相似文献   
106.
Ren  Pan  Deng  Xing  Li  KeZhou  Li  GuiHao  Li  Wei 《Biomechanics and modeling in mechanobiology》2021,20(5):1775-1788
Biomechanics and Modeling in Mechanobiology - Background and Purpose: Most current studies on the passive biomechanical properties of esophageal tissues directly use the exponential strain energy...  相似文献   
107.
林窗环境异质性导致群落物种多样性与系统发育多样性(phylogenetic diversity, PD)存在差异, 研究不同大小的林窗中群落的物种多样性与系统发育多样性有助于揭示林下生物多样性的形成及维持机制。本文以格氏栲(Castanopsis kawakamii)天然林为研究对象, 通过Pearson相关性分析与广义线性模型探讨了林窗内物种多样性与系统发育多样性间的相互关系及其环境影响因素。结果表明: (1)大林窗(面积 > 200 m2)植物种类及多度均高于中林窗(50 m2 ≤ 面积 < 100 m2)、小林窗(30 m2 ≤ 面积 < 50 m2)和非林窗(面积 = 100 m2)。大林窗群落系统发育结构趋于发散, 中、小林窗和非林窗群落系统发育结构受到生境过滤和竞争排斥综合作用。(2)群落系统发育多样性指数与物种丰富度(species richness, SR)、Margalef丰富度指数和Shannon-Wiener指数均呈显著正相关, 这与林窗内稀有种种类组成多于优势种有关。(3)林窗面积对物种多样性存在显著正效应; 土壤全氮含量对系统发育多样性和系统发育结构存在显著正效应。林窗形成提高了格氏栲天然林群落物种多样性和系统发育多样性, 林窗面积与土壤全氮共同驱动了格氏栲天然林林窗物种多样性和系统发育多样性的变化。  相似文献   
108.
隆水蚤科以其丰富的个体数和多样性成为海洋水体生态系统中极为重要的小型桡足类, 但其分类学和多样性研究仍有较大不足, 其生态功能及在生态系统中的地位存在被低估的可能。为了提升对隆水蚤科的认识, 本文对国际隆水蚤科分类学和物种多样性研究进展、隆水蚤科的物种多样性研究难点和技术发展趋势、隆水蚤科的分布和生态等方面研究进行概述。19世纪末Giesbrecht创建隆水蚤科, 随后该科的新物种不断被发现和描述, 目前已描述115种。中国海仅记录到隆水蚤科物种11种, 相关生态学研究较薄弱。隆水蚤科由于个体小, 许多物种间具有高度的形态相似性, 并且包含很多姐妹种及种内分型, 因此许多研究将传统分类鉴定手段与分子生物学技术相结合, 以提高物种的发现和描述效率。随着研究的不断深入, 有关隆水蚤科物种的分布特征、食性特征、种群特征和行为学特征等均得到不同程度的关注, 这都将提高隆水蚤科研究的广度和深度。随着研究技术的迅速发展以及许多设备先进的科学考察船和载人潜水器被用于海洋研究, 从近海、边缘海到深远海研究的协同发展, 海洋生物样品资源不断丰富, 这将带动我国分类和多样性研究快速发展, 使隆水蚤科的分类学研究不断深入。  相似文献   
109.
利用光镜对叉蕨科7属30种植物叶表皮形态特征进行详细观察研究。结果显示:(1)叉蕨科30种植物的叶上表皮和下表皮细胞形状均为不规则型,垂周壁式样为深波状或浅波状,具单晶或针晶;上表皮细胞的长宽比为1.62~4.0,下表皮细胞的长宽比为1.63~3.06。(2)在30种植物中共观察到7种气孔器类型,分别为:极细胞型、腋下细胞型、聚合极细胞型、聚腋下细胞型、不等细胞型、无规则四细胞型和不规则型,每种植物分别具有4~7种气孔器类型,均为下生型气孔;气孔长宽比为1.22~1.91,气孔密度为8~76个/mm2,气孔指数为3.9%~25.7%。(3)基于气孔器类型组成进行聚类分析,可将30种植物分成3个类群。(4)对叶表皮形态特征分析认为,轴脉蕨属应介于叉蕨属和肋毛蕨属之间,且与叉蕨属关系更近;叉蕨属的范畴还有待进一步研究;支持将肋毛蕨属从叉蕨科中分离出来置于鳞毛蕨科,但不支持黄腺羽蕨属归入鳞毛蕨科。  相似文献   
110.
以青藏高原湿地植物为研究对象,通过对青藏高原35个采样点的野外调查采样,对青藏高原湿地植物8种轻金属元素(Al、Mg、Ca、Sr、Ba、K、Na、Li)含量的特征及其与环境因素的关系进行分析。结果显示,不同湿地植物对不同轻金属元素的富集能力存在差异。轻金属元素在湿地植物体内的平均含量依次排序为:Li相似文献   
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