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101.
Nitric oxide (NO) serves as a messenger for cellular signaling and physiological reactions such as inflammatory responses in vivo. Fluorescent bioimaging of nitric oxide is a very useful tool in NO functional research. Although many encouraging results have been achieved in the field of NO fluorescent detection, there is rarely satisfying result in inflammatory NO imaging in vivo. Here we report that fluorescent 5′-chloro-2-(2′-hydroxyphenyl)-1H-naphtho[2,3-d]imidazol can coordinate with Cu(II) to form a non-fluorescent coordination compound, which is able to directly and quickly image NO in cellular system or in vivo inflammation system with a turn-on fluorescence, based on a redox action of Cu(II). It was used to image NO produced by inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS) activated murine macrophages. More importantly, it could image the NO production in an acute severe hepatic injury (ASHI) model of BALB/c mice induced by integrative LPS and d-galactosamine (GalN) treatment. The results prove that the 5′-chloro-2-(2′-hydroxyphenyl)-1H-naphtho[2,3-d]imidazol coordinated with cupric ions can serve as an excellent NO bioimaging agent in different biological systems especially in inflammation related systems, and it may be valuable for diagnostic and pathological studies of NO related diseases.  相似文献   
102.
Cancer is a deadly disease with increasing incidence and mortality rates and affects the life quality of millions of people per year. The past 15 years have witnessed the rapid development of targeted therapy for cancer treatment, with numerous anticancer drugs, drug targets and related gene mutations been identified. The demand for better anticancer drugs and the advances in database technologies have propelled the development of databases related to anticancer drugs. These databases provide systematic collections of integrative information either directly on anticancer drugs or on a specific type of anticancer drugs with their own emphases on different aspects, such as drug–target interactions, the relationship between mutations in drug targets and drug resistance/sensitivity, drug–drug interactions, natural products with anticancer activity, anticancer peptides, synthetic lethality pairs and histone deacetylase inhibitors. We focus on a holistic view of the current situation and future usage of databases related to anticancer drugs and further discuss their strengths and weaknesses, in the hope of facilitating the discovery of new anticancer drugs with better clinical outcomes.  相似文献   
103.
We read with great interest the recent report by Semeghini et al. (2017), Cell Biol Int, “Menopause transition promotes distinct modulation of mRNAs and miRNAs expression in calvaria and bone marrow osteoblastic cells,” which appeared on 24 May 2017 in Cell Biology International. The results of the report are very helpful for us; however, from our perspective, the author's method in bioinformatics analysis is inappropriate: Student's t‐test is an inappropriate statistical method for detecting differentially expressed mRNA or miRNA in osteoblastic cells from calvaria of ovariectomized rats compared to control or in osteoblastic cells from bone marrow of ovariectomized rats compared to control.  相似文献   
104.
微生物农药因其环境友好、无化学残留、可持续控制等优点,在农林病虫害防治中具有重要的发展潜力。近年来,我国设施农业取得极大效益,面积急剧扩大,在农业中占较大比例。随着环保意识的提高,设施农业中的微生物农药施用逐渐推广,但相关研究相对匮乏。为此,本文阐述了设施农业微生物农药的研究发展现状,针对其在设施农业中的表现,提出改良途径,并展望了发展趋势。  相似文献   
105.
106.
Newly synthesized proteins in eukaryotic cells can only function well after they are accurately transported to specific organelles. The establishment of protein databases and the development of programs have accelerated the study of protein subcellular locations, but their comparisons and evaluations of the prediction accuracy of subcellular location programs in plants are lacking. In this study, we built a random test set of maize proteins to evaluate the accuracy of six commonly used programs of subcellular locations: iLoc-Plant, Plant-mPLoc, CELLO, WoLF PSORT, SherLoc2, and Predotar. Our results showed that the accuracy of prediction varied greatly depending on the programs and subcellular locations involved. The programs using homology search methods (iLoc-Plant and Plant-mPLoc) performed better than those using feature search methods (CELLO, WoLF PSORT, SherLoc2, and Predotar). In particular, iLoc-Plant achieved an 84.9 % accuracy for proteins whose subcellular locations have been experimentally determined and a 74.3 % accuracy for all of the proteins in the test set. Regarding locations, the highest prediction accuracies for subcellular locations were obtained for the nucleus, followed by the cytoplasm, mitochondria, plastids, endoplasmic reticulum, and vacuoles, while the lowest were obtained for cell membrane, secreted, and multiple-location proteins. We discussed the accuracy of the six programs in this article. This study will assist plant biologists in choosing appropriate programs to predict the location of proteins and provide clues regarding their function, especially for hypothetical or novel proteins.  相似文献   
107.
Mechanotransduction sensing of tissue architecture and cellular microenvironment is a fundamental regulator of cell fate, including cancer. Meanwhile, long noncoding RNAs (lncRNAs) play multifunctions during cancer development and treatment. However, the link between lncRNAs and cellular mechanotransduction in the context of cancer progression has not yet been elucidated. In this study, using atomic force microscopy (AFM), we find that ionizing radiation reduces tumor stiffness. Ionizing radiation-induced lncRNA CRYBG3 can blunt YAP/TAZ activity through interference with mechanotransduction, resulting in the inhibition of cell proliferation, invasion, and metastasis of lung cancer cells. In vivo, we found that loss of lncRNA CRYBG3 could power the tumor initiation and metastasis ability, but this was abolished by concomitant deplete TAZ. At the molecular level, lncRNA CRYBG3 that in turn dysregulates F-actin organization, activates the LATS1/2 kinase, all in all resulting in YAP/TAZ nuclear exclusion. Our research proposes that lncRNA CRYBG3 is a mediator of radiotherapy through its control of cancer-tissue mechanotransduction and wiring YAP/TAZ activity to control tumor growth and metastasis.Subject terms: Oncogenes, Long non-coding RNAs, Stress fibres  相似文献   
108.
2D metallic transition-metal dichalcogenides (MTMDCs) have attracted widespread research interest in the exploration of fundamental physical issues and energy-related fields. Although relatively high catalytic activity has been predicted theoretically in the new type MTMDCs-based electrocatalysts, their hydrogen evolution reaction (HER) performance is severely hampered by the insufficient catalytic stability due to structural degradation during long-time use and limited active sites in planar electrode structures. Herein, the scalable synthesis of vertically-oriented 2H-NbS2 nanosheets is reported on low-cost carbon nanotube (CNT) film substrates by a facile chemical vapor deposition route. The 3D vertically-oriented 2H-NbS2 nanosheets present abundant edge active sites and strong interface coupling with CNT thus possessing exceptional mechanical stability. These features impart the 3D nanosheets catalysts with remarkably low overpotentials of ≈55 mV at 10 mA cm−2 and ultra-high exchange current density of ≈1445 µA cm−2, and negligible performance degradation after 200 h operation at the large current density, which are superior to those of other TMDCs-based catalysts. This work hereby provides novel perspectives for the batch synthesis and application of 3D MTMDCs-based electrocatalysts with greatly improved electrocatalytic performance and stability that are needed for practical applications.  相似文献   
109.
廖梦娜  金伊丽  李晨瑜  李凯 《生态学报》2020,40(3):1089-1100
青藏高原东南部高寒山区广泛发育冰川湖泊,湖泊沉积过程同时受控于区域气候、流域水文、地质条件及湖泊形态特征。基于放射性210Pb/137Cs和14C定年法,对巴松错沉积物理(粒度、分选系数)和化学指标(TOC、TN、C/N)进行分析,发现18世纪末到19世纪末湖泊沉积过程显著变化,表现为迅速变缓趋势。通过分析区域树轮重建的气候序列(温度、降水及相对湿度)及冰川地貌调查资料,认为气候变化及流域冰川分布位置是影响该湖泊沉积过程的重要因素。小冰期末期冰川前缘靠近湖区,随后温度上升导致冰川融水激增、水动力加强,从而引起湖泊沉积粒度的粗化。随着冰川前缘不断后退,径流输送距离增长、沉积分选变好、粒度细化。此外,该地区活跃的地质活动也可能是湖泊沉积过程明显变化的重要诱因。湖泊沉积硅藻是研究气候环境变化的有力指标。过去200多年巴松错硅藻组合变化不明显(DCCA=0.47 SD),说明该地区气候环境变化未超过其生态阈值。通过与其他沉积指标进行对比分析发现,巴松错硅藻记录受到流域水文和湖泊沉积过程影响,主要表现为外源输入和/或湖岸浅水区来源...  相似文献   
110.
余晨渝  肖作林  刘睿  赵浣玎  王科宇 《生态学报》2022,42(17):7177-7186
植被覆盖变化是生态环境变化的重要指标,定量解析其中的人类活动作用一直是生态领域研究的热点。以重庆市为例,基于遥感、气象以及统计数据,利用GIS技术和残差法,从归一化植被指数(NDVI)和土地利用/覆盖(LUCC)整合分析视角,探究西南山地2000-2020年植被覆盖变化的时空特征,深入解析人类活动影响。 研究表明:(1)近20年间研究区植被覆盖呈整体上升趋势且空间异质性强,渝东南和渝东北地区植被覆盖以及恢复趋势明显优于渝中地区。(2)残差分析表明人类活动对植被覆盖变化同时存在正向和负向两个方面的影响,以正向影响为主导。(3)林地未变区和耕地未变区对植被覆盖变化的贡献程度最大(两者共达到84.18%),退耕还林贡献率仅为1.24%。(4)封禁育林面积与林地未变区植被覆盖变化存在极显著正相关关系(R2=0.82),同时封禁育林生态工程能够较好地解释林地未变区残差变化。研究建立了LUCC对植被覆盖变化影响的贡献率清单,定量揭示封禁育林生态工程对植被覆盖恢复的重要作用,对丰富区域植被覆盖变化驱动研究具有一定参考价值。  相似文献   
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