21 results on '"Li, Zhijin"'
Search Results
2. Progress and future prospects of decadal prediction and data assimilation: A review
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Zhou, Wen, Li, Jinxiao, Yan, Zixiang, Shen, Zili, Wu, Bo, Wang, Bin, Zhang, Ronghua, and Li, Zhijin
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- 2024
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3. The role of Astragalus polysaccharides in promoting IEC-6 cell migration from polyamine-mediated Ca2+ regulation
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Zhang, Dong, Zhu, Yiping, Li, Zhijin, Luo, Meng, Liang, Xinyi, Wang, Anrong, Zhu, Huibin, Hu, Ling, and Li, Ruliu
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- 2022
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4. Anti-fatigue effect of hypericin in a chronic forced exercise mouse model
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Sun, Yang, Liang, Chen, Zheng, Lihua, Liu, Lei, Li, Zhijin, Yang, Guang, and Li, Yuxin
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- 2022
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5. Emergency glioma resection but not hours of operation predicts perioperative complications: A single center study
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Deng, Zhong, Wu, Wei, Wang, Ning, Arafat, Wahap, Li, Zhijin, Wang, Jia, Ren, Chunying, Li, Rihui, Wang, Tuo, Du, Changwang, and Wang, Maode
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- 2019
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6. Conformality and self-duality of Nf = 2 QED3
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Li, Zhijin
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- 2022
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7. 3D CFT archipelago from single correlator bootstrap
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Li, Zhijin and Su, Ning
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- 2019
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8. Pressure injury: A non-negligible comorbidity for critical Covid-19 patients.
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Yu, Nanze, Li, Zhijin, Long, Xiao, Huang, Jiuzuo, Cao, Wei, Zhang, Yan, Yang, Yang, Liu, Zhengyin, Liu, Zhifei, Zhang, Shuyang, and Wang, Xiaojun
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- 2021
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9. Cartilaginous extracellular matrix derived from decellularized chondrocyte sheets for the reconstruction of osteochondral defects in rabbits.
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Wang, Zhifa, Li, Zhiye, Li, Zhijin, Wu, Buling, Liu, Yanpu, and Wu, Wei
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EXTRACELLULAR matrix ,CARTILAGE cells ,OSTEOCHONDROSIS ,TISSUE engineering ,COLLAGEN - Abstract
Graphical abstract Abstract Cartilaginous extracellular matrix (ECM) materials derived from decellularized native articular cartilage are widely used in cartilage regeneration. However, it is difficult for endogenous cells to migrate into ECM derived from native cartilage owing to its nonporous structure and dense nature. Moreover, current decellularization approaches frequently lead to architectural breakdown and potential loss of surface composition of ECM. To solve this problem, we aimed to establish a novel biological ECM scaffold from chondrocyte sheets for cartilage regeneration. We cultured chondrocytes harvested from the auricular cartilage of 4-week-old New Zealand rabbits and enabled them to form cell sheets. These sheets were decellularized using sodium dodecyl sulfate (SDS) with three different concentrations, namely, 1%, 5%, and 10%, followed by 1% Triton X-100 and deoxyribonuclease enzyme solution. In vitro microstructural examination and mechanical tests demonstrated that 1% SDS not only removed chondrocytes completely but also maintained the native architecture and composition of ECM, thus avoiding the use of high-concentration SDS. Application of decellularized chondrocyte sheets for osteochondral defects in rabbits resulted in substantial host remodeling and variant regeneration of osteochondral tissues. One percent SDS-treated decellularized chondrocyte sheets contributed to the superior reconstruction of osteochondral defects as compared with 5% and 10% SDS groups, which includes vascularized subchondral bone, articular cartilage with adequate thickness, and integration with host tissues. Furthermore, ECM from 1% SDS significantly increased the migrating potential of bone marrow mesenchymal stem cells (BMSCs) in vitro. RT-PCR and western blot also revealed that ECM increased the expression of SOX-9 in BMSCs, whereas it decreased COL-X expression. In conclusion, our results suggested that the chondrocyte sheets decellularized with 1% SDS preserved the integrity and bioactivity, which favored cell recruitment and enabled osteochondral regeneration in the knee joints of rabbits, thus offering a promising approach for articular cartilage reconstruction without cell transplantation. Statement of Significance Although biological extracellular matrix (ECM) derived from decellularized native cartilage has been widely used in cartilage regeneration, it is difficult for endogenous cells to migrate into ECM owing to its dense nature. Moreover, current decellularization approaches lead to architectural breakdown of ECM. This study established a novel biological ECM from decellularized chondrocyte sheets for cartilage regeneration. Our results suggested that cartilaginous ECM favored cell recruitment and enabled osteochondral regeneration in rabbits, thus offering a promising approach for articular cartilage reconstruction without cell transplantation. SDS 1% adequately decellularized the chondrocytes in cell sheets, whereas it maintained the native architecture and composition of ECM, thereby avoiding the use of high-concentration SDS and providing a new way to acquire cartilaginous ECM. [ABSTRACT FROM AUTHOR] more...
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- 2018
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10. An efficient SMD-PCBA detection based on YOLOv7 network model.
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Li, Zhijin, Yan, Jinfeng, Zhou, Jie, Fan, Xiaozhen, and Tang, Jiahui
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MACHINE learning , *DEEP learning , *PRINTED circuits , *MANUFACTURING processes - Abstract
Modern Printed Circuit Board Assembly (PCBA) manufacturing processes require more accurate and robust defect inspection methods. Despite the potential of deep learning algorithms in PCBA defect detection, their ability to handle environmental factors and multi-modal data is still limited. To overcome this, we propose an improved YOLOv7-based network model that enhances the detection performance of densely distributed multi-size Surface Mount Devices (SMD) in multi-modal PCBA. Specifically, the proposed model enhances feature representation by designing a detection head based on Coordinate Attention, and incorporates feedback connections in the feature fusion stage to improve feature recognition through low-level propagation. Additionally, we propose the SEIoU loss function to calculate position loss between the prediction box and the ground truth, resulting in superior regression accuracy of the anchor box and improved detection accuracy. We validate the effectiveness and improvement of our proposed method through ablation experiments and algorithm comparison. Our proposed model outperforms the baseline YOLOv7 model with a 2.1% increase in mAP@0.5 for the multi-modal PCBA dataset and a 4.5% increase in mAP@0.5:0.95 for the VOC 2012 dataset, and a 1.0% increase in mAP@0.5:0.95 for the COCO 2017 dataset. Our study's results suggest that our proposed model is a promising alternative to existing methods for detecting PCBA defects, as it accurately detects multiple tiny components amidst complex backgrounds, effectively identifies diverse types of defects, and remains lightweight. [ABSTRACT FROM AUTHOR] more...
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- 2023
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11. Intraglandular Transplantation of Adipose-Derived Stem Cells for the Alleviation of Irradiation-Induced Parotid Gland Damage in Miniature Pigs.
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Wang, Zhifa, Ju, Zhaoyu, He, Longlong, Li, Zhijin, Liu, Yanpu, and Liu, Bin
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Purpose: In a previous study, the authors verified the protective efficacy of adipose-derived stem cells (ADSCs) on the prevention of salivary gland (SG) damage induced by irradiation in mice. As a critical step before implementation in clinical practice, the present study investigated the protective effect of ADSCs in a miniature pig SG model, because miniature pigs share many characteristics with humans.Materials and Methods: Third-passage autologous ADSCs at a concentration of 4 × 106 cells/mL were transplanted by intraglandular injection into parotid glands (PGs) immediately after local irradiation at a single dose of 20 Gy. The injection process was repeated twice a week for 6 consecutive weeks. At 12 weeks after irradiation, functional and histologic evaluations were performed by measuring salivary flow rate (SFR) and hematoxylin and eosin and periodic acid-Schiff staining. Immunohistochemical and transmission electron microscopic examinations also were conducted to evaluate amylase (AMY) production, microvessel density (MVD), and microstructural changes.Results: The irradiated PGs showed remarkable decreases in SFR, AMY production, and MVD. However, transplantation of ADSCs alleviated irradiated PG morphology and function by preserving more functional acinar cells and increasing SFR and AMY production. In addition, greater MVD was observed in the ADSC-treated group than in the irradiated group.Conclusions: These results indicated that intraglandular transplantation of autologous ADSCs is an effective method to protect PGs against damage from irradiation in miniature pigs, which might have clinic application in the future. [ABSTRACT FROM AUTHOR] more...- Published
- 2017
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12. Structure, cytotoxic activity and mechanism of protoilludane sesquiterpene aryl esters from the mycelium of Armillaria mellea.
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Li, Zhijin, Wang, Yunchao, Jiang, Bin, Li, Wenliang, Zheng, Lihua, Yang, Xiaoguang, Bao, Yongli, Sun, Luguo, Huang, Yanxin, and Li, Yuxin
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CARBOXYLIC acids analysis , *ANALYTICAL biochemistry , *COLLECTION & preservation of biological specimens , *CELL lines , *CELL surface antigens , *ANALYTICAL chemistry techniques , *FUNGI , *HERBAL medicine , *IMMUNODIAGNOSIS , *LIVER , *CHINESE medicine , *MOLECULAR structure - Abstract
Ethnopharmacological relevance Armillaria mellea (Vahl. ex. Fr.) Karst is an important traditional Chinese medicine used in dispelling wind and removing obstruction in the meridians, and strengthening tendons and bones. Armillaria mellea has been recorded in the book Caobenshiyi which was written by ancestor for the function of suppressing hyderactive liver for calming endogenous wind medicine. The aim of this study is to investigate the cytotoxic activity for liver cell lines (normal and cancerous) of protoilludane sesquiterpene aryl esters from the mycelium of A. mellea . Materials and methods A systemic fractionation of the mycelium extracts of A. mellea and relative activity mechanisms were studied. Results Two new protoilludane sesquiterpene aryl esters named 5′-methoxy-armillasin (1) and 5-hydroxyl-armillarivin (2) were isolated. In addition, eight known protoilludane sesquiterpene aryl esters armillaridin (3), armillartin (4), armillarin (5), melleolide B (6), armillarilin (7), armillasin (8), armillarigin (9) and melleolide (10) were also isolated from the mycelium of A. mellea . The relative configurations of the two new compounds were confirmed by NOESY spectra. Among ten protoilludane sesquiterpene aryl esters, compounds 2, 3, 4, 7, 8, 9 and 10 were active constituents with highly cytotoxic activity against HepG2 cells (4.95–37.65 μg/mL). We reported here for the time, that compound 10 (melleolide) showed anti-tumor ability on hepatoma cell. The relative mechanism was assessed on HepG2 cells. Conclusions Among all the ten protoilludane sesquiterpene aryl esters, melleolide (10) showed the best cytotoxic activity for HepG2 cells (4.95 μg/mL) and lower activity for L02 cells (16.05 μg/mL). Mechanism study showed that melleolide decreased the viability of the cancer cells with varying levels of cleaved-caspase 3, caspase 8, caspase 9, Bax and Ki67 expression. On the other hand, melleolide induced HepG2 cell cycle arrest at the G2/M phase. [ABSTRACT FROM AUTHOR] more...
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- 2016
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13. Sheet of osteoblastic cells combined with platelet-rich fibrin improves the formation of bone in critical-size calvarial defects in rabbits.
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Wang, Zhifa, Hu, Hanqing, Li, Zhijin, Weng, Yanming, Dai, Taiqiang, Zong, Chunlin, Liu, Yanpu, and Liu, Bin
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PLATELET-rich fibrin ,OSTEOBLASTS ,CALVARIA ,LABORATORY rabbits ,BONE regeneration - Abstract
Techniques that use sheets of cells have been successfully used in various types of tissue regeneration, and platelet-rich fibrin (PRF) can be used as a source of growth factors to promote angiogenesis. We have investigated the effects of the combination of PRF and sheets of mesenchymal stem cells (MSC) from bone marrow on the restoration of bone in critical-size calvarial defects in rabbits to find out whether the combination promotes bony healing. Sheets of MSC and PRF were prepared from the same donor. We then implanted the combined MSC and PRF in critical-size calvarial defects in rabbits and assessed bony restoration by microcomputed tomography (microCT) and histological analysis. The results showed that PRF significantly increased bony regeneration at 8 weeks after implantation of sheets of MSC and PRF compared with sheets of MSC alone ( p = 0.0048). Our results indicate that the combination of sheets of MSC and PRF increases bone regeneration in critical-size calvarial defects in rabbits, and provides a new way to improve skeletal healing. [ABSTRACT FROM AUTHOR] more...
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- 2016
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14. Protective efficacy of intravenous transplantation of adipose-derived stem cells for the prevention of radiation-induced salivary gland damage.
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Li, Zhijin, Wang, Yan, Xing, Hongyan, Wang, Zhifa, Hu, Hanqing, An, Ran, Xu, Haiyan, Liu, Yanpu, and Liu, Bin
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STEM cell transplantation , *ADIPOSE tissues , *SALIVARY gland diseases , *RADIATION damage , *RADIATION doses , *XEROSTOMIA - Abstract
Objective High-dose radiation therapy in the head and neck area can lead to irreversible damage to salivary glands (SGs) with consequent xerostomia. Adipose-derived stem cells (ADSCs) have been shown to repair or rescue damaged SGs. Thus, we investigated the protective efficacy of ADSCs in the prevention of SG damage induced by high dose radiation. Methods Third-passage ADSCs (1 × 10 6 ) were transplanted by intravenous infusion into the tail-vein of 8-week-old C57BL/6 mice, immediately after local irritation at a dose of 18 Gy. The process was repeated twice a week during a period of six consecutive weeks. Eight weeks after radiation, functional evaluations were conducted by measuring salivary flow rate (SFR). Histological, immunohistochemical and transmission electron microscopic (TEM) examinations were performed to analyze microstructural and ultrastructural changes, microvessel density, amylase production, apoptosis, and proliferation activity. Results Intravenously administrated ADSCs could home to irradiated SGs within 24 h after infusion, significantly increasing SG weights, improving SFR, and preserving the microscopic morphologies of SGs eight weeks post-radiation. More functional acini, higher amylase production levels, and higher microvessel densities were observed in ADSC-treated SGs than in irradiated SGs. Additionally, enhanced cell proliferation activity and reduced radiation-induced SG apoptosis was observed in the ADSC-treated group when compared with the irradiated group. Conclusion Systemic administration of ADSCs immediately after radiation at a dose of 18 Gy can protect both the morphology and function of SGs eight weeks after radiation in mice, and can be used as a protective measure for the prevention of SG damage induced by high-dose radiation. [ABSTRACT FROM AUTHOR] more...
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- 2015
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15. Solid-state grain growth of garnet single crystals of complex composition.
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Li, ZhiJin, Nian, HongQiang, Feng, Tao, and Jiang, Danyu
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SOLID state chemistry , *METAL crystal growth , *GARNET , *SINGLE crystals , *COMPLEX compounds , *PRECIPITATION (Chemistry) , *POLYCRYSTALS , *NEODYMIUM - Abstract
Various (Nd-doped (Y,Gd,La,Lu)3(Sc,Al)5O12) garnets were reproducibly grown from a Nd-doped (Y,Gd,La,Lu)3(Sc,Al)5O12 polycrystalline precursor. Single crystals were grown through controlled abnormal grain growth at temperatures between 1750°C and 1850°C. Nd-doped (Y,Gd,La,Lu)3(Sc,Al)5O12 powder was prepared using the co-precipitation method, and single crystals were fabricated by the conversion of polycrystalline material. The phase identification of the specimens was performed using XRD and X-ray double crystal rocking curve (DCRC) analysis. The absorption spectra, fluorescence spectra, and fluorescence lifetimes of samples excited using an 808nm laser diode (LD) were also measured. The fluorescence lifetime of Nd-doped (Y,Gd,La,Lu)3(Sc,Al)5O12 single crystals is longer than that of Nd:YAG; a prolonged fluorescence lifetime helps to achieve a high laser output power. In short, we can fabricate complex mixed-garnet single crystals using the solid-state single-crystal conversion (SCC) method. [ABSTRACT FROM AUTHOR] more...
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- 2014
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16. Development, implementation and evaluation of a data-assimilative ocean forecasting system off the central California coast
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Chao, Yi, Li, Zhijin, Farrara, John, McWilliams, James C., Bellingham, James, Capet, Xavier, Chavez, Francisco, Choi, Jei-Kook, Davis, Russ, Doyle, Jim, Fratantoni, David M., Li, Peggy, Marchesiello, Patrick, Moline, Mark A., Paduan, Jeff, and Ramp, Steve more...
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OCEAN engineering , *GEOPHYSICAL prediction , *COASTS , *MATHEMATICAL models , *OPTICAL resolution , *REAL-time control , *ALGORITHMS , *DATA analysis - Abstract
Abstract: The development and implementation of a real-time ocean forecast system based on the Regional Ocean Modeling System (ROMS) off the coast of central California are described. The ROMS configuration consists of three nested modeling domains with increasing spatial resolutions: the US West coastal ocean at 15-km resolution, the central California coastal ocean at 5km, and the Monterey Bay region at 1.5km. All three nested models have 32 vertical sigma (or terrain-following) layers and were integrated in conjunction with a three-dimensional variational data assimilation algorithm (3DVAR) to produce snapshots of the ocean state every 6h (the reanalysis) and 48-h forecasts once a day. This ROMS forecast system was operated in real time during the field experiment known as the Autonomous Ocean Sampling Network (AOSN-II) in August 2003. After the field experiment, a number of improvements were made to the ROMS forecast system: more data were added in the reanalysis with more careful quality control procedures, improvements were made in the data assimilation scheme, as well as model surface and side boundary conditions. The results from the ROMS reanalysis are presented here. The ROMS reanalysis is first compared with the assimilated data as a consistency check. An evaluation of the ROMS reanalysis against the independent measurements that are not assimilated into the model is then presented. This evaluation shows the mean differences in temperature and salinity between reanalysis and observations to be less than 1°C and 0.2psu (practical salinity unit), respectively, with root-mean-square (RMS) differences of less than 1.5°C and 0.25psu. Qualitative agreement is found between independent current measurements and the ROMS reanalysis. The agreement is particularly good for the vertically integrated current along the offshore glider tracks: the ROMS reanalysis can realistically reproduce the poleward California Undercurrent. Reasonably good agreement is found in the spatial patterns of the surface current as measured by high-frequency (HF) radars. Preliminary results concerning the ROMS forecast skill and predictability are also presented. Future plans to improve the ROMS forecast system with a particular focus on assimilation of HF radar current measurements are discussed. [Copyright &y& Elsevier] more...
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- 2009
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17. Optimal control of cylinder wakes via suction and blowing
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Li, Zhijin, Navon, I.M., Hussaini, M.Y., and Le Dimet, F.-X.
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DISTRIBUTED parameter systems , *NAVIER-Stokes equations , *WAKES (Fluid dynamics) - Abstract
A general method based on adjoint formulation is discussed for the optimal control of distributed parameter systems (including boundary parameter) which is especially suitable for large dimensional control problems. Strategies for efficient and robust implementation of the method are described. The method is applied to the problem of controlling vortex shedding behind a cylinder (through suction/blowing on the cylinder surface) governed by the unsteady two-dimensional incompressible Navier–Stokes equations space discretized by finite-volume approximation with time-dependent boundary conditions. Three types of objective functions are considered, with regularization to circumvent ill-posedness. These objective functions involve integration over a space–time domain. The minimization of the cost function uses a quasi-Newton DFP method.A complete control of vortex shedding is demonstrated for Reynolds numbers up to 110. The optimal values of the suction/blowing parameters are found to be insensitive to initial conditions of the model when the time window of control is larger than the vortex shedding period, the inverse of the Strouhal frequency. Although this condition is necessary for robust control, it is observed that a shorter window of control may suffice to suppress vortex shedding. [Copyright &y& Elsevier] more...
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- 2003
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18. Integrative analysis of DNA methylation and gene expression profiles identifies MIR4435-2HG as an oncogenic lncRNA for glioma progression.
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Li, Zhijin, Tan, Hua, Zhao, Weiling, Xu, Yungang, Zhang, Zhigang, Wang, Maode, and Zhou, Xiaobo
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GENE expression profiling , *DNA methylation , *DNA analysis , *METHYLGUANINE , *NON-coding RNA - Abstract
Long noncoding RNAs (lncRNAs) have been shown to play an important role in tumor biogenesis and prognosis. The glioma is a grade classified cancer, however, we still lack the knowledge on their function during glioma progression. While previous studies have shown how lncRNAs regulate protein-coding gene epigenetically, it is still unclear how lncRNAs are regulated epigenetically. In this study, we firstly analyzed the RNA-seq data systematically across grades II, IV, and IV of glioma samples. We identified 60 lncRNAs that are significantly differentially expressed over disease progression (DElncRNA), including well-known PVT1, HOTAIR, H19 and rarely studied CARD8-AS, MIR4435-2HG. Secondly, by integrating HM450K methylation microarray data, we demonstrated that some of the lncRNAs are epigenetically regulated by methylation. Thirdly, we developed a DESeq2-GSEA-ceRNA-survival analysis strategy to investigate their functions. Particularly, MIR4435-2HG is highly expressed in high-grade glioma and may have an impact on EMT and TNFα signaling pathway by functioning as a miRNA sponge of miR-125a-5p and miR-125b-5p to increase the expression of CD44. Our results revealed the dynamic expression of lncRNAs in glioma progression and their epigenetic regulation mechanism. • We identified some epigenetically upregulated lncRNAs in glioma progression. • lncRNA PVT1 is epigenetically upregulated by methylation. • Upregulated MIR4435-2HG is associated with poor survival. • MIR4435-2HG may regulate the EMT and TNF-α pathways by upregulating CD44 by acting as CeRNA. [ABSTRACT FROM AUTHOR] more...
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- 2019
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19. E2F transcription factor 8 promotes proliferation and radioresistance in glioblastoma.
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Yu, Hai, Zhang, Duanni, Li, Zhijin, and Wang, Maode
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TRANSCRIPTION factors , *BRAIN tumors , *GLIOBLASTOMA multiforme , *CELL proliferation , *GLIOMAS , *ONCOGENES - Abstract
Glioblastoma (GBM) is the most lethal brain tumor that has a median survival of less than 2 years. Tumor heterogeneity and high therapeutic resistance are hallmarks of GBM. Transcription factors (TFs) play a critical role in tumor progression by regulating the transcriptional events associated with tumor cells transition into more malignant cellular phenotypes. The E2 F transcription factor 8 (E2 F8) is a recently identified TF in the E2 F family. Studies have revealed that E2 F8 is involved in tumorigenesis of multiple cancer types; however, the oncogenic role of E2 F8 in GBM was rarely studied and the prognostic value of E2 F8 has not been explored. In this study, we investigated the expression profile, prognosis correlation and oncogenic role of E2 F8 to explore its potential use as a GBM therapeutic target. E2 F8 was significantly enriched in GBM compared with normal brain tissues and low-grade glioma. E2 F8 high expression was strongly associated with worse outcome of GBM patients. E2 F8 silencing significantly attenuated the proliferation of tumor cells in vitro and tumorigenicity in vivo , while its overexpression promoted the proliferation of GBM tumor cells. Bioinformatics analysis revealed that E2 F8 was tightly linked to multiple oncogenic processes in GBM, including aggressive cell cycle, DNA repair, STAT3, TGFRβ and WNT pathways. E2 F8 high expression correlated with the expression of a variety of well-known oncogenes in GBM. E2 F8 was identified as a crucial transcriptional regulator of CHEK1 via its directly binding CHEK1 promoter area. Finally, E2 F8 conferred significant radioresistance to GBM tumor cells in vitro and in vivo. E2 F8 is highly expressed in GBM and associated with worse outcome in GBM patients. It promotes tumorigenesis and radioresistance of GBM tumor cells and has oncogenic roles via its involvement in multiple oncogenic processes and pathways such as the regulation of CHEK1 transcriptional activity. [ABSTRACT FROM AUTHOR] more...
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- 2020
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20. Estimating ground-level PM10 concentration in northwestern China using geographically weighted regression based on satellite AOD combined with CALIPSO and MODIS fire count.
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You, Wei, Zang, Zengliang, Zhang, Lifeng, Li, Zhijin, Chen, Dan, and Zhang, Gui
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REGRESSION analysis , *ARTIFICIAL satellites , *MODIS (Spectroradiometer) , *REMOTE sensing , *ATMOSPHERIC aerosols , *PARTICULATE matter - Abstract
Satellite measurements have been widely used to estimate particulate matters (PMs) on the ground and their effects on human health. However, such estimation depends critically on an established relation between aerosol optical depth (AOD) and ground level PMs. In this study we performed an experiment at Xi'an to establish a relation between AOD and PM10. A first test of satellite AOD and PM10 data showed a low correlation between the two properties, especially in spring and summer seasons with relatively many high AOD values paired to low ground-level PM10 values, which hinted that AOD may ‘contaminate’ by summer agricultural burning season and dust storm intrusion leading to much elevated aerosol. MODIS fire count and CALIPSO vertical feature mask data were used to detect fire emissions and elevated aerosol to substantiate this hypothesis. A later test showed that the correlation between AOD and PM10 has strongly been improved by excluding the paired AOD-PM10 data with known biomass burning and elevated aerosol layers. This result indicates that summer agricultural burning and aloft aerosol should be considered when the AOD–PM10 association is explored. Finally, a geographically weighted regression model was developed to further improve estimation of ground-level concentration by combining AOD with meteorological parameters. The results showed that the meteorological parameters can greatly improve model performance. The overall cross-validation R 2 is 0.77 and the root mean squared prediction error (RMSE) is 16.91 μg/m 3 . These results are useful for developing satellite AOD based model to estimate ground-level PMs especially for the region with known strong biomass burning events. [ABSTRACT FROM AUTHOR] more...
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- 2015
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21. Modeling tides in Monterey Bay, California
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Wang, Xiaochun, Chao, Yi, Dong, Changming, Farrara, John, Li, Zhijin, McWilliams, James C., Paduan, Jeffrey D., and Rosenfeld, Leslie K.
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TIDES , *MATHEMATICAL models , *GEOPHYSICAL prediction , *OCEAN circulation , *TIDE gages , *RADIO in oceanography , *RADAR , *SEA level , *OCEAN currents , *BAROCLINIC models - Abstract
Abstract: In the process of developing a tide-permitting coastal ocean forecasting system, tidal signals are added to an oceanic general circulation model for Monterey Bay, California. The model, which is configured from the regional ocean modeling system (ROMS), has three one-way nested domains with the finest resolution of 1.6km in the horizontal direction and 32 levels in the vertical direction. In present research, the tidal simulation of the system is validated against tide gauges, ADCP current observations, high-frequency radar surface-current observations, and compared with the output from two barotropic tidal models. The results indicate that the barotropic tides from the model compare well with observations in terms of sea-surface height, with discrepancies in amplitude of less than 10% of the amplitude of the most energetic constituent. However, the discrepancy for the barotropic tidal currents can reach 30% among models with similar accuracy in sea-surface height. The generation and propagation of baroclinic tides associated with the Monterey Submarine Canyon are qualitatively reproduced by the model with weaker strength. The surface tidal current simulation is improved, especially in terms of magnitude, when the model has a more realistic stratification through changes in both barotropic and baroclinic tidal currents. [Copyright &y& Elsevier] more...
- Published
- 2009
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