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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   
93.
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   
94.
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   
95.
The expression and new functions of reproductive hormones in organs beyond hypothalamus-pituitary-gonad axis have been reported. So far, there is no report about the protective effects of GnRH analogue to hippocampal neurons suffering from ischemia–reperfusion injury. Middle cerebral artery occlusion model together with TUNEL staining were made in vivo and oxygen-glucose deprivation model together with double staining of Annexin V/PI with flow cytometer were made in vitro to observe the anti-apoptotic effects of GnRH analogue to hippocampal neurons after ischemia–reperfusion injury. The results found that the number of TUNEL positive pyramidal neurons in CA1 region in GnRH analogue experiment group was less than that in control group in vivo; the percentage of apoptotic neurons in GnRH analogue experiment group was less than that in control group in vitro. These findings suggested that pretreatment with certain concentration of GnRH analogue could attenuate apoptosis of hippocampal neurons. GnRH analogue has the protective effects to neurons.  相似文献   
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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   
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In this study, we aimed to predict newly diagnosed patient responses to antiepileptic drugs (AEDs) using resting-state functional magnetic resonance imaging tools to explore changes in spontaneous brain activity. We recruited 21 newly diagnosed epileptic patients, 8 drug-resistant (DR) patients, 11 well-healed (WH) patients, and 13 healthy controls. After a 12-month follow-up, 11 newly diagnosed epileptic patients who showed a poor response to AEDs were placed into the seizures uncontrolled (SUC) group, while 10 patients were enrolled in the seizure-controlled (SC) group. By calculating the amplitude of fractional low-frequency fluctuations (fALFF) of blood oxygen level-dependent signals to measure brain activity during rest, we found that the SUC patients showed increased activity in the bilateral occipital lobe, particularly in the cuneus and lingual gyrus compared with the SC group and healthy controls. Interestingly, DR patients also showed increased activity in the identical cuneus and lingual gyrus regions, which comprise Brodmann’s area 17 (BA17), compared with the SUC patients; however, these abnormalities were not observed in SC and WH patients. The receiver operating characteristic (ROC) curves indicated that the fALFF value of BA17 could differentiate SUC patients from SC patients and healthy controls with sufficient sensitivity and specificity prior to the administration of medication. Functional connectivity analysis was subsequently performed to evaluate the difference in connectivity between BA17 and other brain regions in the SUC, SC and control groups. Regions nearby the cuneus and lingual gyrus were found positive connectivity increased changes or positive connectivity changes with BA17 in the SUC patients, while remarkably negative connectivity increased changes or positive connectivity decreased changes were found in the SC patients. Additionally, default mode network (DMN) regions showed negative connectivity increased changes or negative changes with BA17 in the SUC patients. The abnormal increased in BA17 activity may be a key point that plays a substantial role in facilitating seizure onset.  相似文献   
100.
Gastric cancer is one of the most common malignancies and has a high rate of metastasis. We hypothesize that NME2 (Nucleoside Diphosphate Kinase 2), which has previously been considered as an anti-metastatic gene, plays a role in the invasiveness of gastric cancer cells. Using a tissue chip technology and immunohistochemistry, we demonstrated that NME2 expression was associated with levels of differentiation of gastric cancer cells and their metastasis into the lymph nodes. When the NME2 gene product was over-expressed by ;in vitro stable transfection, cells from BGC823 and MKN45 gastric cancer cell lines had reduced rates of proliferation, migration, and invasion through the collagen matrix, suggesting an inhibitory activity of NME2 in the propagation and invasion of gastric cancer. NME2 could, therefore, severe as a risk marker for gastric cancer invasiveness and a potential new target for gene therapy to enhance or induce NME2 expression.  相似文献   
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