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71.
Yi‐Lin Chen Gao‐Xiong Wang Bei‐An Lin Jing‐Shan Huang 《Cell biology international》2020,44(5):1224-1236
This work aimed to investigate miR‐93‐5p expression in tumor tissue and its in vitro effects in colorectal cancer (CRC) by targeting programmed death ligand‐1 (PD‐L1). MiR‐93‐5p and PD‐L1 expression was detected in CRC and adjacent normal tissues by quantitative real‐time polymerase chain reaction and immunohistochemistry. The correlation between miR‐93‐5p and PD‐L1 was validated by a dual‐luciferase reporter assay. HCT116 and SW480 cells were divided into blank, miR‐NC, miR‐93‐5p mimics, miR‐93‐5p inhibitor, PD‐L1 small interfering RNA (siRNA) and miR‐93‐5p inhibitor + PD‐L1 siRNA groups, and wound‐healing and transwell assays were performed to detect cell migration and invasion, respectively. Protein expression was measured by western blotting. The secretion of cytokines was detected in the CRC cell/T coculture models. MiR‐93‐5p was downregulated in CRC tissues with upregulated PD‐L1. In PD‐L1‐negative patients, miR‐93‐5p expression was increased compared with that in PD‐L1‐positive patients. MiR‐93‐5p and PD‐L1 expression levels were associated with the tumor differentiation, lymphatic metastasis, TNM, Duke's stage, and prognosis of CRC. PD‐L1 siRNA weakened the migration and invasion abilities via decreased expression of matrix metalloproteinase‐1 (MMP‐1), ‐2, and ‐9, and these effects were abolished by the miR‐93‐5p inhibitor. Additionally, anti‐PD‐L1 upregulated the expressions of interleukin‐2 (IL‐2), tumor necrosis factor‐α (TNF‐α), and interferon γ (IFN‐γ) in the coculture of T cells with CRC cells, but downregulated the expressions of IL‐1β, IL‐10, and TGF‐β. However, these changes were partially reversed by miR‐93‐5p inhibition. miR‐93‐5p is expected to be a novel target for CRC treatment since it decreases the migration and invasion, as well as the immune evasion, of CRC cells via targeting PD‐L1. 相似文献
72.
Huolin Luo Yuelong Liang Hanwen Xiao Nannan Liu Yanru Chen Wu Wang Jiang Tang Dongjin Xiong Boyun Yang Zongxin Ren 《Entomological Science》2020,23(1):3-9
Flowers have developed different strategies to attract pollinators through visual or olfactory signals. Most flowers offer pollinators a reward (e.g. nectar and pollen) for the pollination service. However, one‐third of Orchidaceae have been shown not to provide a reward. Calanthe are terrestrial orchids distributed throughout China, Nepal, Japan and tropical Asia. Despite its high diversity, the pollination biology of Calanthe remains largely unknown, even though it is an important aspect of plant conservation. In the study, through field surveying, there were three Hesperiidae butterflies pollinating two species of Calanthe and the pollination behavior differed between the two species of Calanthe, which might lead to different fruit setting rates. There was no nectar in the flowers of the two species, indicating deceptive pollination. Using a glass cylinder experiment, it was deduced that the two species of Calanthe were most likely to attract pollinators by generalized food deception. Interestingly, Hesperiidae butterflies were traditionally thought to be nectar thieves and generally do not transmit pollinia. However, our findings showed that, in this case, the thieves were deceived by the plants and pollinated them for free. 相似文献
73.
Quan Zhang Mallory Barnes Michael Benson Elizabeth Burakowski A. Christopher Oishi Andrew Ouimette Rebecca Sanders‐DeMott Paul C. Stoy Matt Wenzel Lihua Xiong Koong Yi Kimberly A. Novick 《Global Change Biology》2020,26(6):3384-3401
Land‐use/cover change (LUCC) is an important driver of environmental change, occurring at the same time as, and often interacting with, global climate change. Reforestation and deforestation have been critical aspects of LUCC over the past two centuries and are widely studied for their potential to perturb the global carbon cycle. More recently, there has been keen interest in understanding the extent to which reforestation affects terrestrial energy cycling and thus surface temperature directly by altering surface physical properties (e.g., albedo and emissivity) and land–atmosphere energy exchange. The impacts of reforestation on land surface temperature and their mechanisms are relatively well understood in tropical and boreal climates, but the effects of reforestation on warming and/or cooling in temperate zones are less certain. This study is designed to elucidate the biophysical mechanisms that link land cover and surface temperature in temperate ecosystems. To achieve this goal, we used data from six paired eddy‐covariance towers over co‐located forests and grasslands in the temperate eastern United States, where radiation components, latent and sensible heat fluxes, and meteorological conditions were measured. The results show that, at the annual time scale, the surface of the forests is 1–2°C cooler than grasslands, indicating a substantial cooling effect of reforestation. The enhanced latent and sensible heat fluxes of forests have an average cooling effect of ?2.5°C, which offsets the net warming effect (+1.5°C) of albedo warming (+2.3°C) and emissivity cooling effect (?0.8°C) associated with surface properties. Additional daytime cooling over forests is driven by local feedbacks to incoming radiation. We further show that the forest cooling effect is most pronounced when land surface temperature is higher, often exceeding ?5°C. Our results contribute important observational evidence that reforestation in the temperate zone offers opportunities for local climate mitigation and adaptation. 相似文献
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76.
Yuanming Xiao Lucun Yang Xiuqing Nie Changbin Li Feng Xiong Lingling Wang Guoying Zhou 《Ecology and evolution》2020,10(13):6723-6731
Periodic climatic oscillations and species dispersal during the postglacial period are two important causes of plant assemblage and distribution on the Qinghai‐Tibet Plateau (QTP). To improve our understanding of the bio‐geological histories of shrub communities on the QTP, we tested two hypotheses. First, the intensity of climatic oscillations played a filtering role during community structuring. Second, species dispersal during the postglacial period contributed to the recovery of species and phylogenetic diversity and the emergence of phylogenetic overdispersion. To test these hypotheses, we investigated and compared the shrub communities in the alpine and desert habitats of the northeastern QTP. Notably, we observed higher levels of species and phylogenetic diversity in the alpine habitat than in the desert habitat, leading to phylogenetic overdispersion in the alpine shrub communities versus phylogenetic clustering in the desert shrub communities. This phylogenetic overdispersion increased with greater climate anomalies. These results suggest that (a) although climate anomalies strongly affect shrub communities, these phenomena do not act as a filter for shrub community structuring, and (b) species dispersal increases phylogenetic diversity and overdispersion in a community. Moreover, our investigation of the phylogenetic community composition revealed a larger number of plant clades in the alpine shrub communities than in the desert shrub communities, which provided insights into plant clade‐level differences in the phylogenetic structures of alpine and desert shrub communities in the northeastern QTP. 相似文献
77.
Bin Liu Xin Zheng Jiajun Li Xiong Li Ruimei Wu Jing Yang Wei Liu Gaoping Zhao 《Bioscience reports》2021,41(1)
Objective: The traditional Chinese medicine Caulis Sargentodoxae is widely used in the treatment of ulcerative colitis (UC), but the mechanism remains unknown. The present study aims to reveal its effective components, targets and pathways through network pharmacology and bioinformatics approaches.Materials and methods: Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) was used to identify effective components. The ligand-based targets prediction was achieved through SwissTargetPrediction and TargetNet. UC-related targets were identified using Gene Expression Omnibus (GEO) data and DisGeNET. The common targets of disease and components were constructed and analyzed by PPI network. Lastly, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses are used to explain the functions of these common targets. Components-Targets-Pathways network was visualized and analyzed to further reveal the connection between the components and targets.Results: Eight active components and 102 key targets were identified to play an important role in UC. These targets were related to regulation of protein serine/threonine kinase activity, positive regulation of cell motility, response to molecule of bacterial origin, response to toxic substance, ERK1 and ERK2 cascade, peptidyl-tyrosine modification, inositol lipid-mediated signaling, cellular response to drug, regulation of inflammatory response and leukocyte migration. Moreover, HIF-1 signaling pathway and PI3K-Akt signaling pathway were the key targets involved in UC-related signaling pathways.Conclusion: The eight active components of Caulis Sargentodoxae mainly play a therapeutic role for UC through synergistic regulation of HIF-1 signaling pathway and PI3K-Akt signaling pathway. 相似文献
78.
Radiation-induced hair cell injury is detrimental for human health but the underlying mechanism is not clear. MicroRNAs (miRNAs) have critical roles in various types of cellular biological processes. The present study investigated the role of miR-222 in the regulation of ionizing radiation (IR)-induced cell injury in auditory cells and its underlying mechanism. Real-time PCR was performed to identify the expression profile of miR-222 in the cochlea hair cell line HEI-OC1 after IR exposure. miRNA mimics or inhibitor-mediated up- or down-regulation of indicated miRNA was applied to characterize the biological effects of miR-222 using MTT, apoptosis and DNA damage assay. Bioinformatics analyses and luciferase reporter assays were applied to identify an miRNA target gene. Our study confirmed that IR treatment significantly suppressed miR-222 levels in a dose-dependent manner. Up-regulation of miR-222 enhances cell viability and alleviated IR-induced apoptosis and DNA damage in HEI-OC1 cells. In addition, BCL-2-like protein 11 (BCL2L11) was validated as a direct target of miR-222. Overexpression of BCL2L11 abolished the protective effects of miR-222 in IR-treated HEI-OC1 cells. Moreover, miR-222 alleviated IR-induced apoptosis and DNA damage by directly targeting BCL2L11. The present study demonstrates that miR-222 exhibits protective effects against irradiation-induced cell injury by directly targeting BCL2L11 in cochlear cells. 相似文献
79.
Wang Han Shen Yi-Jia Li Xiu-Juan Xia Jun Sun Li Xu Yehao Ma Yu Li Dai Xiong Yuan-Chang 《Neurochemical research》2021,46(5):1214-1223
Neurochemical Research - Paclitaxel is a common chemotherapeutic agent in cancer treatment, while it often causes chemotherapy-induced peripheral neuropathy (CIPN), which... 相似文献
80.
Wang Guang-Long An Ya-Hong Wang Ya-Hui Liu Jie-Xia Wang Ji-Zhong Sun Min Xiong Ai-Sheng 《Journal of Plant Growth Regulation》2021,40(2):787-797
Journal of Plant Growth Regulation - Gibberellins (GAs) are a group of plant hormones that play important roles in various processes. Previous studies demonstrated that GA can increase the... 相似文献