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Differentially Expressed MicroRNAs in the Development of Early Diabetic Retinopathy

Qiaoyun Gong, Jia'nan Xie, Yang Liu, Ying Li, Guanfang Su
2017 Journal of Diabetes Research  
The pathological mechanisms of diabetic retinopathy (DR), a leading cause of blindness in adults with diabetes mellitus, remain incompletely understood. Because microRNAs (miRNAs) represent effective DR therapeutic targets, we identified aberrantly expressed miRNAs associated with cellular dysfunction in early DR and detected their potential targets. We exposed human retinal endothelial cells (HRECs) and a cell line of retinal pigment epithelial (RPE) cells to high glucose (25 mmol/L, 1–7 days)
more » ... to mimic DR progression and used streptozotocin-injected rats (4–8 weeks) for an in vivo diabetes model. HREC/RPE viability decreased after 24 h incubation and diminished further over 6 days, and Hoechst staining revealed hyperglycemia-induced HREC/RPE apoptosis. Although miR-124/-125b expression decreased with DR progression in vitro and in vivo, miR-135b/-199a levels decreased in retinal cells under hyperglycemia exposure, but increased in diabetic retinas. Moreover, miR-145/-146a expression decreased gradually in high-glucose-treated HRECs, but increased in hyperglycemia-exposed RPE cells and in diabetic rats. Our findings suggested that aberrant miRNA expression could be involved in hyperglycemia-induced retinal-cell dysfunction, and the identified miRNAs might vary in different retinal layers, with expression changes associated with DR development. Therefore, miRNA modulation and the targeting of miRNA effects on transcription factors could represent novel and effective DR-treatment strategies.
doi:10.1155/2017/4727942 pmid:28706953 pmcid:PMC5494571 fatcat:mswcttwmwrc4djezomktx3ggsq

Dynamic Behavior of Laminated Graphite/Epoxy Composite under High-Strain Rate Perforation Loading

Qiaoyun Xie, Sylvanus N. Wosu
2013 Journal of Materials Science Research  
A high strain rate perforation split Hopkinson pressure bar (P-SHPB) test apparatus was developed for the quantification analysis of energy expenditure in the penetration or perforation mechanics, and dynamic fracture failure processes of laminated graphite/epoxy composite. This paper described the basic features of the P-SHPB system for perforation testing, characterized of high strain rate, and single mode as well as mixed modes of fracture failures of laminated composites. The results showed
more » ... that the energy expended in a perforation process depends on the thickness of the laminate samples, the impact parameters and the incident stress delivered to the composite. The failure modes in graphite/epoxy composite exhibited four regions of damage mechanism and characterized on the basis of energy absorbed, impact energy, loading force, sample stress and strain rate. Perforation limit velocity was estimated by extrapolating the (impact velocity) 2 and crack length curve to a zero-damage length and determining the velocity value. Keywords: P-SHPB, energy expenditure, high strain rate, failure modes, perforation limit velocity Studies (Dee, Vinson, & Sankar, 1997) have shown that energy expended in the damage process is proportional to the thickness of the target plate and the energy absorbed and damage sustained are not linear functions of impact (energy) velocity. Within a certain range, the damage mechanism appears dependent on energy absorbed by the sample, while within other energy ranges, the damage mechanism appears governed by the striker velocity. Thus, the use of the damage threshold impact energy alone to characterize the damage event may not be an ideal criterion and maybe influenced by other mechanisms. Of interest is to understand the wave-induced damage near the perforation limit threshold and to characterize the modes of fracture which occur. where m s is the mass of the 0.61 m striker bar equal to 2.47 kg, the compressor pressure p is in MPa, striker
doi:10.5539/jmsr.v3n1p30 fatcat:tmmcjuk7pjhdbjydjmer2qctc4

Dynamic Fracture Toughness of TaC/CNTs/SiC CMCs Prepared by Spark Plasma Sintering

Qiaoyun Xie, Sylvanus N. Wosu
2015 Advances in Materials Science and Engineering  
This study focuses on the fracture toughness of TaC and carbon nanotubes (CNTs) reinforced SiC ceramic matrix composites (CMCs), prepared by spark plasma sintering (SPS) technique. A high densification of 98.4% was achieved under the sintering parameter of 133°C/min, 1800°C, and 90 MPa pressure. Vickers indentation was employed to measure the indentation toughness on the polished surface of ceramic samples, SEM was applied to directly observe the crack propagation after indentation, and split
more » ... pkinson pressure bar (SHPB) was developed to determine the dynamic fracture toughness within the ceramic samples subjected to an impact in a three-point bending configuration.
doi:10.1155/2015/510356 fatcat:ozdx6oki5nfwng3q26s2mrooye

Estimating Peanut Leaf Chlorophyll Content with Dorsiventral Leaf Adjusted Indices: Minimizing the Impact of Spectral Differences between Adaxial and Abaxial Leaf Surfaces

Mengmeng Xie, Zhongqiang Wang, Alfredo Huete, Luke A. Brown, Heyu Wang, Qiaoyun Xie, Xinpeng Xu, Yanling Ding
2019 Remote Sensing  
Relatively little research has assessed the impact of spectral differences among dorsiventral leaves caused by leaf structure on leaf chlorophyll content (LCC) retrieval. Based on reflectance measured from peanut adaxial and abaxial leaves and LCC measurements, this study proposed a dorsiventral leaf adjusted ratio index (DLARI) to adjust dorsiventral leaf structure and improve LCC retrieval accuracy. Moreover, the modified Datt (MDATT) index, which was insensitive to leaves structure, was
more » ... ized for peanut plants. All possible wavelength combinations for the DLARI and MDATT formulae were evaluated. When reflectance from both sides were considered, the optimal combination for the MDATT formula was ( R 723 − R 738 ) / ( R 723 − R 722 ) with a cross-validation R2cv of 0.91 and RMSEcv of 3.53 μg/cm2. The DLARI formula provided the best performing indices, which were ( R 735 − R 753 ) / ( R 715 − R 819 ) for estimating LCC from the adaxial surface (R2cv = 0.96, RMSEcv = 2.37 μg/cm2) and ( R 732 − R 754 ) / ( R 724 − R 773 ) for estimating LCC from reflectance of both sides (R2cv = 0.94, RMSEcv = 2.81 μg/cm2). A comparison with published vegetation indices demonstrated that the published indices yielded reliable estimates of LCC from the adaxial surface but performed worse than DLARIs when both leaf sides were considered. This paper concludes that the DLARI is the most promising approach to estimate peanut LCC.
doi:10.3390/rs11182148 fatcat:ep27hic5sndfzkuh66pbh6w23q

A Transformed Triangular Vegetation Index for Estimating Winter Wheat Leaf Area Index

Naichen Xing, Wenjiang Huang, Qiaoyun Xie, Yue Shi, Huichun Ye, Yingying Dong, Mingquan Wu, Gang Sun, Quanjun Jiao
2019 Remote Sensing  
Leaf area index (LAI) is a key parameter in plant growth monitoring. For several decades, vegetation indices-based empirical method has been widely-accepted in LAI retrieval. A growing number of spectral indices have been proposed to tailor LAI estimations, however, saturation effect has long been an obstacle. In this paper, we classify the selected 14 vegetation indices into five groups according to their characteristics. In this study, we proposed a new index for LAI retrieval-transformed
more » ... ngular vegetation index (TTVI), which replaces NIR and red bands of triangular vegetation index (TVI) into NIR and red-edge bands. All fifteen indices were calculated and analyzed with both hyperspectral and multispectral data. Best-fit models and k-fold cross-validation were conducted. The results showed that TTVI performed the best predictive power of LAI for both hyperspectral and multispectral data, and mitigated the saturation effect. The R2 and RMSE values were 0.60, 1.12; 0.59, 1.15, respectively. Besides, TTVI showed high estimation accuracy for sparse (LAI < 4) and dense canopies (LAI > 4). Our study provided the value of the Red-edge bands of the Sentinel-2 satellite sensors in crop LAI retrieval, and demonstrated that the new index TTVI is applicable to inverse LAI for both low-to-moderate and moderate-to-high vegetation cover.
doi:10.3390/rs12010016 fatcat:aheomjfmozdihepmznvfi7p254

Identification and Validation of Immune Cells and Hub Genes in Gastric Cancer Microenvironment

Huan Wang, Jianfang Rong, Qiaoyun Zhao, Conghua Song, Rulin Zhao, Sihai Chen, Yong Xie, Ting Su
2022 Disease Markers  
Gastric cancer (GC) is the most common malignant tumor in the digestive system, traditional radiotherapy and chemotherapy are not effective for some patients. The research progress of immunotherapy seems to provide a new way for treatment. However, it is still urgent to predict immunotherapy biomarkers and determine novel therapeutic targets. In this study, the gene expression profiles and clinical data of 407 stomach adenocarcinoma (STAD) patients were downloaded from The Cancer Genome Atlas
more » ... CGA) portal, and the abundance ratio of immune cells in each sample was obtained via the "Cell Type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT)" algorithm. Five immune cells were obtained as a result of abundance comparison, and 295 immune-related genes were obtained through differential gene analysis. Enrichment, protein interaction, and module analysis were performed on these genes. We identified five immune cells associated with infiltration and 20 hub genes, of which five genes were correlated with overall survival. Finally, we used Real-time PCR (RT-PCR) to detect the expression differences of the five hub genes in 18 pairs of GC and adjacent tissues. This research not only provides cellular and gene targets for immunotherapy of GC but also provides new ideas for researchers to explore immunotherapy for various tumors.
doi:10.1155/2022/8639323 pmid:35422890 pmcid:PMC9005323 fatcat:ory2wybrnzdctfpopoiln3ihna

YAP Inhibition by Nuciferine via AMPK-Mediated Downregulation of HMGCR Sensitizes Pancreatic Cancer Cells to Gemcitabine

Ling Zhou, Qiaoyun Wang, Han Zhang, Youjie Li, Shuyang Xie, Maolei Xu
2019 Biomolecules  
Nuciferine, a major aporphine alkaloid constituent of lotus leaves, is a raw material for obesity treatment. Extensive studies have revealed that obesity is associated with pancreatic cancer (PC). However, it has not been clarified whether nuciferine could be used in PC treatment or prevention. Here, we show that nuciferine could enhance the sensitivity of PC cells to gemcitabine in both cultured cells and the xenograft mouse model. The mechanism study demonstrated that nuciferine induced YAP
more » ... r127 phosphorylation [pYAP(Ser127)] through AMPK-mediated 3-hydroxy-3-methyl-glutaryl-coA reductase (HMGCR) downregulation. Remarkably, wild-type YAP overexpression or YAP Ser127 mutant could resist to nuciferine and no longer sensitize PC cells to gemcitabine. Knockdown of AMPK attenuated pYAP(Ser127) induced by nuciferine. Moreover, knockdown of AMPK reversed nuciferine-mediated HMGCR downregulation. Notably, HMGCR inhibiting could restrain YAP by phosphorylation Ser 127, and therefore enhance the efficiency of gemcitabine in PC cells. In line with this consistent, overexpression of HMGCR reduced growth inhibition caused by nuciferine and/or gemcitabine treatment in PC cells. In summary, these results provide an effective supplementary agent and suggest a therapeutic strategy to reduce gemcitabine resistance in PC.
doi:10.3390/biom9100620 pmid:31627466 pmcid:PMC6843496 fatcat:5otwedmx7jgwhauv24czbgb2zy

Expression of the phosphodiesterase BifA facilitating swimming motility is partly controlled by FliA inPseudomonas putidaKT2440

Yujie Xiao, Huizhong Liu, Hailing Nie, Shan Xie, Xuesong Luo, Wenli Chen, Qiaoyun Huang
2016 MicrobiologyOpen  
R E S E A R C H Expression of the phosphodiesterase BifA facilitating swimming motility is partly controlled by FliA in Pseudomonas putida KT2440 Yujie Xiao 1 | Huizhong Liu 1 | Hailing Nie 1 | Shan Xie  ...  1 | Xuesong Luo 1,2 | Wenli Chen 1 | Qiaoyun Huang 1,2 | INTRODUCTION Flagella-mediated motility is an important capability of many bacteria to explore the environment for nutrients and escape from  ...  ., Xie, S., Luo, X., Chen, W. and Huang, Q. Expression of the phosphodiesterase BifA facilitating swimming motility is partly controlled by FliA in Pseudomonas putida KT2440.  ... 
doi:10.1002/mbo3.402 pmid:27663176 pmcid:PMC5300878 fatcat:yzvx5pcadjhk7ebvz2k3hqyje4

Joint Retrieval of Winter Wheat Leaf Area Index and Canopy Chlorophyll Density Using Hyperspectral Vegetation Indices

Naichen Xing, Wenjiang Huang, Huichun Ye, Yu Ren, Qiaoyun Xie
2021 Remote Sensing  
Leaf area index (LAI) and canopy chlorophyll density (CCD) are key biophysical and biochemical parameters utilized in winter wheat growth monitoring. In this study, we would like to exploit the advantages of three canonical types of spectral vegetation indices: indices sensitive to LAI, indices sensitive to chlorophyll content, and indices suitable for both parameters. In addition, two methods for joint retrieval were proposed. The first method is to develop integration-based indices
more » ... ng LAI-sensitive and CCD-sensitive indices. The second method is to create a transformed triangular vegetation index (TTVI2) based on the spectral and physiological characteristics of the parameters. PROSAIL, as a typical radiative transfer model embedded with physical laws, was used to build estimation models between the indices and the relevant parameters. Validation was conducted against a field-measured hyperspectral dataset for four distinct growth stages and pooled data. The results indicate that: (1) the performance of the integrated indices from the first method are various because of the component indices; (2) TTVI2 is an excellent predictor for joint retrieval, with the highest R2 values of 0.76 and 0.59, the RMSE of 0.93 m2/m2 and 104.66 μg/cm2, and the RRMSE (Relative RMSE) of 12.76% and 16.96% for LAI and CCD, respectively.
doi:10.3390/rs13163175 fatcat:2qa23prmzjct3gfeb5tppppglq

Upregulated VEGF and Robo4 correlate with the reduction of miR-15a in the development of diabetic retinopathy

Qiaoyun Gong, Fuqiang Li, Jia'nan Xie, Guanfang Su
2019 Endocrine (Basingstoke)  
Vascular endothelial growth factor (VEGF) plays implicated roles in diabetic retinopathy (DR). The role of roundabout 4 (Robo 4) in angiogenesis and vasculogenesis is controversial; however, the interdependent relationship between these two factors has not been studied in DR. This study determined the colocalization of VEGF and Robo4 in fibrovascular membranes (FVM) from patients with proliferative diabetic retinopathy (PDR). MicroRNA (miRNA)-mediated modulation of VEGF and Robo4 was explored
more » ... diabetic rats and ARPE-19 tissue culture cells under hyperglycemia.
doi:10.1007/s12020-019-01921-0 pmid:30980286 pmcid:PMC6606763 fatcat:xdqthdtr6bfn5irslorof4lpqm

Supraglottic jet oxygenation and ventilation saved a patient with 'cannot intubate and cannot ventilate' emergency difficult airway

Qiaoyun Li, Ping Xie, Benjun Zha, ZhiYun Wu, Huafeng Wei
2016 Journal of Anesthesia  
Ping Xie) of the present study had learnt the technique of SJOV via nasal assembly (Fig. 1 ) from a national airway workshop in China just two months previously.  ... 
doi:10.1007/s00540-016-2279-x pmid:27848018 pmcid:PMC5288426 fatcat:xjdnmsmdonefpfvl3z4eyvadkm

Increased IGFBP7 Expression Correlates with Poor Prognosis and Immune Infiltration in Gastric Cancer

Qiaoyun Zhao, Rulin Zhao, Conghua Song, Huan Wang, Jianfang Rong, Fangfei Wang, Lili Yan, Yanping Song, Yong Xie
2021 Journal of Cancer  
Insulin-like growth factor binding protein-7 (IGFBP7) contributes to multiple biological processes in various tumors. However, the role of IGFBP7 in gastric cancer (GC) is still undetermined. The study aims to explore the role of IGFBP7 in GC via an integrated bioinformatics analysis. Methods: IGFBP7 expression levels in GC and its normal gastric tissues were analyzed using multiple databases, including the Tumor Immune Estimation Resource (TIMER), Oncomine, The Cancer Genome Atlas (TCGA) and
more » ... ne Expression Omnibus (GEO) databases, as well as by our clinical gastric specimens. The methylation analysis was conducted with MEXPRESS, UALCAN and Xena online tools. The survival analysis was conducted using the Kaplan-Meier Plotter and Gene Expression Profiling Interactive Analysis (GEPIA) databases. Coexpressed genes of IGFBP7 were selected with the cBioPortal tool and enrichment analysis was conducted with the clusterProfiler package in R software. Gene set enrichment analysis (GSEA) was performed to explore the IGFBP7-related biological processes involved in GC. Correlations between IGFBP7 and immune cell infiltrates were analyzed using the TIMER database. Results: IGFBP7 expression was significantly upregulated in GC and correlated with stage, grade, tumor status and Helicobacter pylori infection. High IGFBP7 expression and low IGFBP7 methylation levels were significantly associated with short survival of patients with GC. Univariate and multivariate analyses revealed that IGFBP7 was an independent risk factor for GC. The coexpressed genes LHFPL6, SEPTIN4, HSPB2, LAYN and GGT5 predicted unfavorable outcomes of GC. Enrichment analysis showed that the coexpressed genes were involved in extracellular matrix (ECM)-related processes. GSEA indicated that IGFBP7 was positively related to ECM and inflammation-related pathways. TIMER analysis indicated that the mRNA level of IGFBP7 was strongly correlated with genes related to various infiltrating immune cells in GC, especially with gene markers of tumor associated macrophages (TAMs). Conclusions: Increased IGFBP7 expression correlates with poor prognosis and immune cell infiltration in GC, which might be a potential biomarker for the diagnosis of GC.
doi:10.7150/jca.50370 pmid:33531979 pmcid:PMC7847654 fatcat:mcllzzvmznaz3hyz2gi4ag727a

In-vitro characterisation of a novel antimicrobial agent, TNP-2092, against Helicobacter pylori clinical isolates

Ben Wang, Qiaoyun Zhao, Wenzhu Yin, Ying Yuan, Xiaomei Wang, You-hua Wang, Hui Wang, Wen Ye, Shuping Chen, Hai-long Guo, Yong Xie
2018 Swiss Medical Weekly  
BACKGROUND AND OBJECTIVES: TNP-2092 is a novel dual-action lead compound consisting of rifamycin SV and 4H-4-oxo-quinolizine pharmacophores, with a broad spectrum of antibacterial activities. This compound is currently in the early stage of clinical development for Helicobacter pylori infection. The aim of the present study was to determine the antibacterial activity of TNP-2092 against H. pylori isolated from primary patients. METHODS: A total of 100 H. pylori clinical isolates from primary
more » ... ients were selected. The minimum inhibitory concentrations (MICs) for clarithromycin, levofloxacin, rifampin and TNP-2092 were determined using an agar dilution method. A time-kill study was performed with different concentrations of TNP-2092 relevant to MIC against H. pylori ATCC strain 43504 for up to 24 hours. The timekill study with drug concentrations of 0-4 × MIC was also used to determine the antibacterial activity of TNP-2092 against H. pylori under different pH conditions (pH 4-7). RESULTS: The primary resistance percentages to clarithromycin, levofloxacin, rifampin and TNP-2092 were 13, 18, 1 and 1%, respectively. TNP-2092 killing kinetics were both concentration and time dependent. The effectiveness of TNP-2092 against H. pylori was gradually reduced with a decrease in pH. CONCLUSIONS: TNP-2092 is highly active against H. pylori and against strains resistant to clarithromycin or levofloxacin. Its antibacterial activity is both concentrationand time-dependent .The antibacterial activity of TNP-2092 appears to be pH-dependent and is more active under neutral pH. TNP-2092 represents a promising new therapy for the treatment of H. pylori infection in primary patients.
doi:10.4414/smw.2018.14630 pmid:30044468 fatcat:e43yybuv7zhtxdlj5tehdfgd3e

Cypermethrin Induces Macrophages Death through Cell Cycle Arrest and Oxidative Stress-Mediated JNK/ERK Signaling Regulated Apoptosis

Fang Huang, Qiaoyun Liu, Shujun Xie, Jian Xu, Bo Huang, Yihua Wu, Dajing Xia
2016 International Journal of Molecular Sciences  
Cypermethrin is one of the most highly effective synthetic pyrethroid insecticides. The toxicity of cypermethrin to the reproductive and nervous systems has been well studied. However, little is known about the toxic effect of cypermethrin on immune cells such as macrophages. Here, we investigated the cytotoxicity of cypermethrin on macrophages and the underlying molecular mechanisms. We found that cypermethrin reduced cell viability and induced apoptosis in RAW 264.7 cells. Cypermethrin also
more » ... creased reactive oxygen species (ROS) production and DNA damage in a dose-dependent manner. Moreover, cypermethrin-induced G1 cell cycle arrest was associated with an enhanced expression of p21, wild-type p53, and down-regulation of cyclin D1, cyclin E and CDK4. In addition, cypermethrin treatment activated MAPK signal pathways by inducing c-Jun N-terminal kinase (JNK) and extracellular regulated protein kinases 1/2 ERK1/2 phosphorylation, and increased the cleaved poly ADP-ribose polymerase (PARP). Further, pretreatment with antioxidant N-acetylcysteine (NAC) effectively abrogated cypermethrin-induced cell cytotoxicity, G1 cell cycle arrest, DNA damage, PARP activity, and JNK and ERK1/2 activation. The specific JNK inhibitor (SP600125) and ERK1/2 inhibitor (PD98059) effectively reversed the phosphorylation level of JNK and ERK1/2, and attenuated the apoptosis. Taken together, these data suggested that cypermethrin caused immune cell death via inducing cell cycle arrest and apoptosis regulated by ROS-mediated JNK/ERK pathway.
doi:10.3390/ijms17060885 pmid:27322250 pmcid:PMC4926419 fatcat:7ir7d3c6vzgctclcc34brjbjkm

A Comparison of Estimating Crop Residue Cover from Sentinel-2 Data Using Empirical Regressions and Machine Learning Methods

Yanling Ding, Hongyan Zhang, Zhongqiang Wang, Qiaoyun Xie, Yeqiao Wang, Lin Liu, Christopher C. Hall
2020 Remote Sensing  
Quantifying crop residue cover (CRC) on field surfaces is important for monitoring the tillage intensity and promoting sustainable management. Remote-sensing-based techniques have proven practical for determining CRC, however, the methods used are primarily limited to empirical regression based on crop residue indices (CRIs). This study provides a systematic evaluation of empirical regressions and machine learning (ML) algorithms based on their ability to estimate CRC using Sentinel-2
more » ... ral Instrument (MSI) data. Unmanned aerial vehicle orthomosaics were used to extracted ground CRC for training Sentinel-2 data-based CRC models. For empirical regression, nine MSI bands, 10 published CRIs, three proposed CRIs, and four mean textural features were evaluated using univariate linear regression. The best performance was obtained by a three-band index calculated using (B2 − B4) / (B2 − B12), with an R2cv of 0.63 and RMSEcv of 6.509%, using a 10-fold cross-validation. The methodologies of partial least squares regression (PLSR), artificial neural network (ANN), Gaussian process regression (GPR), support vector regression (SVR), and random forest (RF) were compared with four groups of predictors, including nine MSI bands, 13 CRIs, a combination of MSI bands and mean textural features, and a combination of CRIs and textural features. In general, ML approaches achieved high accuracy. A PLSR model with 13 CRIs and textural features resulted in an accuracy of R2cv = 0.66 and RMSEcv = 6.427%. An RF model with predictors of MSI bands and textural features estimated CRC with an R2cv = 0.61 and RMSEcv = 6.415%. The estimation was improved by an SVR model with the same input predictors (R2cv = 0.67, RMSEcv = 6.343%), followed by a GPR model based on CRIs and textural features. The performance of GPR models was further improved by optimal input variables. A GPR model with six input variables, three MSI bands and three textural features, performed the best, with R2cv = 0.69 and RMSEcv = 6.149%. This study provides a reference for estimating CRC from Sentinel-2 imagery using ML approaches. The GPR approach is recommended. A combination of spectral information and textural features leads to an improvement in the retrieval of CRC.
doi:10.3390/rs12091470 fatcat:vj753t3v3fekti7va53fxyjola
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