22 results on '"Shimin Xu"'
Search Results
2. Combined gestational age and serum fucose for early prediction of risk for bronchopulmonary dysplasia in premature infants
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Liangliang Li, Shimin Xu, Miaomiao Li, Xiangyun Yin, Hongmin Xi, Ping Yang, Lili Ma, Lijuan Zhang, and Xianghong Li
- Subjects
Bronchopulmonary dysplasia ,Serum monosaccharides ,Monosaccharide composite (MC) ,High-performance liquid chromatography ,Prediction model ,Pediatrics ,RJ1-570 - Abstract
Abstract Objective As the predominant complication in preterm infants, Bronchopulmonary Dysplasia (BPD) necessitates accurate identification of infants at risk and expedited therapeutic interventions for an improved prognosis. This study evaluates the potential of Monosaccharide Composite (MC) enriched with environmental information from circulating glycans as a diagnostic biomarker for early-onset BPD, and, concurrently, appraises BPD risk in premature neonates. Materials and methods The study incorporated 234 neonates of ≤32 weeks gestational age. Clinical data and serum samples, collected one week post-birth, were meticulously assessed. The quantification of serum-free monosaccharides and their degraded counterparts was accomplished via High-performance Liquid Chromatography (HPLC). Logistic regression analysis facilitated the construction of models for early BPD diagnosis. The diagnostic potential of various monosaccharides for BPD was determined using Receiver Operating Characteristic (ROC) curves, integrating clinical data for enhanced diagnostic precision, and evaluated by the Area Under the Curve (AUC). Results Among the 234 neonates deemed eligible, BPD development was noted in 68 (29.06%), with 70.59% mild (48/68) and 29.41% moderate-severe (20/68) cases. Multivariate analysis delineated several significant risk factors for BPD, including gestational age, birth weight, duration of both invasive mechanical and non-invasive ventilation, Patent Ductus Arteriosus (PDA), pregnancy-induced hypertension, and concentrations of two free monosaccharides (Glc-F and Man-F) and five degraded monosaccharides (Fuc-D, GalN-D, Glc-D, and Man-D). Notably, the concentrations of Glc-D and Fuc-D in the moderate-to-severe BPD group were significantly diminished relative to the mild BPD group. A potent predictive capability for BPD development was exhibited by the conjunction of gestational age and Fuc-D, with an AUC of 0.96. Conclusion A predictive model harnessing the power of gestational age and Fuc-D demonstrates promising efficacy in foretelling BPD development with high sensitivity (95.0%) and specificity (94.81%), potentially enabling timely intervention and improved neonatal outcomes.
- Published
- 2024
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3. Spatiotemporal Variation Characteristics and Source Identification of Nitrogen in the Baiyangdian Lake Water, China
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Qianqian Zhang, Shimin Xu, and Li Yang
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lakes ,nitrogen ,water quality ,source identification ,principal component analysis ,Hydraulic engineering ,TC1-978 ,Water supply for domestic and industrial purposes ,TD201-500 - Abstract
To study the characteristics and sources of nitrogen in the Baiyangdian Lake, this research conducted water quality monitoring during three hydrological periods (normal period, flood period, and dry period), and 165 pieces of routine water quality monitoring data were collected from the three national control sections for Baiyangdian Lake and its inflow rivers. By integrating water chemical analysis with multivariate statistical techniques, the study comprehensively investigated the spatiotemporal variation patterns of nitrogen in Baiyangdian Lake and identified the sources of nitrogen pollution. The results showed that the concentration of total nitrogen (TN) was highest during the dry period, reaching an average of 0.924 mg/L, and 31.3% of the sites exceeded the national Grade III surface water quality standard, reflecting a potential risk of nitrogen pollution. Based on the ion ratio method and principal component analysis (PCA), the main sources of nitrogen pollution in Baiyangdian Lake were identified as manure and domestic sewage, with agricultural fertilizers also having a certain impact on water nitrogen pollution. In addition, the study also compared the nitrogen concentration in Baiyangdian Lake with several important lakes in China. The results showed that the concentrations of TN and ammonium nitrogen (NH4+-N) in Baiyangdian Lake are lower than those in lakes in areas with similar human activity intensity, indicating that the water quality of Baiyangdian is relatively good. This study can provide a scientific basis for water quality management and pollution prevention for Baiyangdian Lake.
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- 2024
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4. Optimal deployment of the online monitoring equipment at the edges of substations considering spatial constraint
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Wenxiang Xu, Shaocong Tong, Shimin Xu, Baigang Du, Dezheng Liu, and Tao Qin
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Mechanical engineering and machinery ,TJ1-1570 - Abstract
To realize the optimal deployment of online monitoring equipment at the edges of substations under the cloud-edge collaboration framework, an optimal deployment model of edges considering spatial constraints is proposed. In the model, the constraints including edge deployment point, line of sight, as well as device pose, etc. are taken into account. To achieve the one-to-many collection of the deployed equipment, a mathematical model is constructed with the objectives of minimizing the shooting distance and the number of edge equipments. And an archive based multi-objective simulated annealing algorithm based on improved trending Markov chain (IAMOSA) is proposed to solve the problem. This algorithm utilizes greedy clustering to initialize deployment points, and the improved disturbance step length with tendency is used to search the neighborhood space. Besides, polynomial fitting Pareto front is also used to select and guide the Markov chain and archive population. Finally, the feasibility and effectiveness of the proposed model and algorithm are verified through an experiment of optimal deployment of the edge equipments in a certain substation.
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- 2024
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5. Improved Scheme for Data Aggregation of Distributed Oracle for Intelligent Internet of Things
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Ruiyang Gao, Yongtao Xue, Wei Wang, Yin Lu, Guan Gui, and Shimin Xu
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blockchain ,data privacy ,homomorphic encryption ,Internet of Things ,Oracle ,Chemical technology ,TP1-1185 - Abstract
Oracle is a data supply mechanism that provides real-world data for blockchain. It serves as a bridge between blockchain and the IoT world, playing a crucial role in solving problems such as data sharing and device management in the IoT field. The main challenge at this stage is determining how to achieve data privacy protection in distributed Oracle machines to safeguard the value hidden in data on the blockchain. In this paper, we propose an improved scheme for distributed Oracle data aggregation based on Paillier encryption algorithm, which achieves end-to-end data privacy protection from devices to users. To address the issue of dishonest distributed Oracle machines running out of funds, we have designed an algorithm called PICA (Paillier-based InChain Aggregation). Based on the aggregation on the Chainlink chain and the Paillier encryption algorithm, random numbers are introduced to avoid the problem of dishonest Oracle machines running out of funds. We use the traffic coverage method to solve the problem of exposed request paths in distributed Oracle machines. Simulation and experimental results show that in small and medium-sized IoT application scenarios with 10,000 data nodes, each additional false request in a single request will result in a delay of about 2 s in data acquisition and can achieve a request response time of 20 s. The proposed method can achieve user data privacy protection.
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- 2024
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6. A comparative study in healthy and diabetic mice followed the exposure of polystyrene microplastics: Differential lipid metabolism and inflammation reaction
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Su Liu, Zhizhi Wang, Qi Xiang, Bing Wu, Wang Lv, and Shimin Xu
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Polystyrene microplastics (PS-MPs) ,Diabetic mice ,Lipid metabolism ,Inflammation ,Environmental pollution ,TD172-193.5 ,Environmental sciences ,GE1-350 - Abstract
Human exposure to microplastics (MPs) continues to occur due to ingestion of contaminated food, water and air. Intake of MPs can pose potential health risks by interfering with the production and circulation of nutrients, leading to physiological stress (such as immune responses and metabolic abnormalities). Toxicity data of MPs based on healthy individuals may not be applicable to large populations of patients with chronic diseases represented by diabetes. Therefore, in this study, the response of diabetic mice was compared with that of healthy mice after exposure to polystyrene microplastics (PS-MPs), and interesting differences were observed. PS-MPs exposure significantly increased liver tissue damage, abnormal lipid metabolism, inflammatory effect, liver metabolic disorder and changes of intestinal microbial composition in diabetic mice. Moreover, PS-MPs overstated abnormal lipid metabolism in diabetic mice. The difference between the increased inflammation after exposure to PS-MPs in healthy and diabetic mice involves that the former is mainly modulated by gut microbes, while diabetic mice seem to be more susceptible to lipid metabolism disturbances. In addition, the size effect of MPs was also observed in diabetic mice. These results suggested that individuals with chronic diseases may be more sensitive to pollution due to altered homeostasis, and therefore disease status should be fully considered when assessing the health risk of pollutants.
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- 2022
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7. GmbZIP1 negatively regulates ABA-induced inhibition of nodulation by targeting GmENOD40–1 in soybean
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Shimin Xu, Shanshan Song, Xiaoxu Dong, Xinyue Wang, Jun Wu, Ziyin Ren, Xuesong Wu, Jingjing Lu, Huifang Yuan, Xinying Wu, Xia Li, and Zhijuan Wang
- Subjects
ABA ,Nodulation ,GmbZIP1 ,GmENOD40–1 ,Soybean ,Botany ,QK1-989 - Abstract
Abstract Background Abscisic acid (ABA) plays an important role in plant growth and adaptation through the ABA signaling pathway. The ABA-responsive element binding (AREB/ABF) family transcriptional factors are central regulators that integrate ABA signaling with various signaling pathways. It has long been known that ABA inhibits rhizobial infection and nodule formation in legumes, but the underlying molecular mechanisms remain elusive. Results Here, we show that nodulation is very sensitive to ABA and exogenous ABA dramatically inhibits rhizobial infection and nodule formation in soybean. In addition, we proved that GmbZIP1, an AREB/ABF transcription factor, is a major regulator in both nodulation and plant response to ABA in soybean. GmbZIP1 was specifically expressed during nodule formation and development. Overexpression of GmbZIP1 resulted in reduced rhizobial infection and decreased nodule number. Furthermore, GmbZIP1 is responsive to ABA, and ectopic overexpression of GmbZIP1 increased sensitivity of Arabidopsis plants to ABA during seed germination and postgerminative growth, and conferred enhanced drought tolerance of plants. Remarkably, we found that GmbZIP1 directly binds to the promoter of GmENOD40–1, a marker gene for nodule formation, to repress its expression. Conclusion Our results identified GmbZIP1 as a node regulator that integrates ABA signaling with nodulation signaling to negatively regulate nodule formation.
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- 2021
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8. GAI Functions in the Plant Response to Dehydration Stress in Arabidopsis thaliana
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Zhijuan Wang, Liu Liu, Chunhong Cheng, Ziyin Ren, Shimin Xu, and Xia Li
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drought ,ga ,della ,abf2 ,protein–protein interaction ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
DELLA (GAI/RGA/RGL1/RGL2/RGL3) proteins are key negative regulators in GA (gibberellin) signaling and are involved in regulating plant growth as a response to environmental stresses. It has been shown that the DELLA protein PROCERA (PRO) in tomato promotes drought tolerance, but its molecular mechanism remains unknown. Here, we showed that the gai-1 (gibberellin insensitive 1) mutant (generated from the gai-1 (Ler) allele (with a 17 amino acid deletion within the DELLA domain of GAI) by backcrossing gai-1 (Ler) with Col-0 three times), the gain-of-function mutant of GAI (GA INSENSITIVE) in Arabidopsis, increases drought tolerance. The stomatal density of the gai-1 mutant was increased but its stomatal aperture was decreased under abscisic acid (ABA) treatment conditions, suggesting that the drought tolerance of the gai-1 mutant is a complex trait. We further tested the interactions between DELLA proteins and ABF2 (abscisic acid (ABA)-responsive element (ABRE)-binding transcription factors) and found that there was a strong interaction between DELLA proteins and ABF2. Our results provide new insight into DELLA proteins and their role in drought stress tolerance.
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- 2020
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9. MiR-98 Protects Nucleus Pulposus Cells against Apoptosis by Targeting TRAIL in Cervical Intervertebral Disc Degeneration
- Author
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Shimin Xu, Yuezhong Li, Junshan Zhang, Zhiwei Li, and Yanping Xing
- Subjects
Lipopolysaccharides ,Medicine (General) ,Nucleus Pulposus ,Article Subject ,Biomedical Engineering ,Health Informatics ,Apoptosis ,Intervertebral Disc Degeneration ,MicroRNAs ,R5-920 ,Medical technology ,Humans ,Surgery ,R855-855.5 ,Biotechnology ,Research Article - Abstract
The excessive apoptosis of nucleus pulposus (NP) cells is a major risk factor in the progress of cervical intervertebral disc degeneration (IVDD). In this study, we investigated the impact of miR-98 on apoptosis of NP cells and the potential molecular mechanisms. Lipopolysaccharide (LPS) was used to establish an NP cell IVDD model. The sponging effect of miR-98 on TRAIL 3′UTR was predicted by ENCORI and assessed by the dual-luciferase reporter gene system. The expression levels of miR-98, TRAIL, and TRAIL pathway-related genes were tested by qRT-PCR, Western blot, and immunofluorescence analysis. Cell apoptosis was analyzed by Hoechst 33258 staining and flow cytometry. Cell viability was analyzed by MTT assay. It was found that the expression level of miR-98 was downregulated, while the level of TRAIL was upregulated in IVDD tissues, and their levels were negatively and positively associated with the clinical MRI grade, respectively. The LPS treatment resulted in a significant decrease of the miR-98 expression level and an increase of the TRAIL expression level in NP cells. miR-98 reduced NP cell apoptosis under LPS treatment in vitro. miR-98 directly targeted TRAIL. Moreover, the mRNA and protein levels of DR5, FADD, cleaved caspase8, cleaved caspase3, and cleaved PARP were downregulated by miR-98 overexpression. Overexpression of TRAIL partially reversed the suppressive roles of miR-98 on cell apoptosis and activation of the TRAIL pathway. We concluded that miR-98 inhibited apoptosis of NP cells by inactivating the TRAIL pathway via targeting TRAIL in IVDD NP cells. These results indicated that miR-98 might be a therapeutic target for IVDD.
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- 2022
10. GmbZIP1 negatively regulates ABA-induced inhibition of nodulation by targeting GmENOD40–1 in soybean
- Author
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Xiaoxu Dong, Xinying Wu, Xuesong Wu, Jingjing Lu, Shimin Xu, Zhijuan Wang, Huifang Yuan, Jun Wu, Ziyin Ren, Shanshan Song, Xinyue Wang, and Xia Li
- Subjects
0106 biological sciences ,0301 basic medicine ,Drought tolerance ,Regulator ,Plant Development ,Plant Science ,Biology ,Nodulation ,01 natural sciences ,Marker gene ,Plant Root Nodulation ,03 medical and health sciences ,chemistry.chemical_compound ,Gene Expression Regulation, Plant ,lcsh:Botany ,Arabidopsis ,Abscisic acid ,Transcription factor ,organic chemicals ,fungi ,food and beverages ,biology.organism_classification ,Plants, Genetically Modified ,lcsh:QK1-989 ,Cell biology ,030104 developmental biology ,chemistry ,ABA ,Germination ,GmbZIP1 ,GmENOD40–1 ,Soybeans ,Signal transduction ,Soybean ,010606 plant biology & botany ,Research Article ,Abscisic Acid ,Rhizobium ,Signal Transduction ,Transcription Factors - Abstract
BackgroundAbscisic acid (ABA) plays an important role in plant growth and adaptation through the ABA signaling pathway. The ABA-responsive element binding (AREB/ABF) family transcriptional factors are central regulators that integrate ABA signaling with various signaling pathways. It has long been known that ABA inhibits rhizobial infection and nodule formation in legumes, but the underlying molecular mechanisms remain elusive.ResultsHere, we show that nodulation is very sensitive to ABA and exogenous ABA dramatically inhibits rhizobial infection and nodule formation in soybean. In addition, we proved that GmbZIP1, an AREB/ABF transcription factor, is a major regulator in both nodulation and plant response to ABA in soybean.GmbZIP1was specifically expressed during nodule formation and development. Overexpression ofGmbZIP1resulted in reduced rhizobial infection and decreased nodule number. Furthermore,GmbZIP1is responsive to ABA, and ectopic overexpression ofGmbZIP1increased sensitivity of Arabidopsis plants to ABA during seed germination and postgerminative growth, and conferred enhanced drought tolerance of plants. Remarkably, we found that GmbZIP1 directly binds to the promoter ofGmENOD40–1, a marker gene for nodule formation, to repress its expression.ConclusionOur results identified GmbZIP1 as a node regulator that integrates ABA signaling with nodulation signaling to negatively regulate nodule formation.
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- 2021
11. Modeling of Intermesh Schedule for Strong Heavy Plate Roller Straightener and Finite Element Method Modification
- Author
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Meng Xu, Dengyue Sun, Shimin Xu, Peng Chen, and Hao Sun
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Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Regarding straightening unit as the research object, considered the different of roller spacing, a mathematical model of intermesh schedule suitable to the 2800 seven-roller strong heavy plate straightening machine was deduced by the geometric method. According to the mathematical model, the intermesh schedules of several specifications of plate were calculated, and the finite element model of straightening process was established in the finite element analysis software Abaqus. By analysing, it was found that those plates after straightening cannot meet the requirement of flatness, due to the existence of the work hardening. The bending deflection of the last straightening unit was modified and the new calculation formula of intermesh schedule was obtained. The values of the modified coefficients were determined by the finite element method. The intermesh schedules of other specifications of plate were calculated by the modified calculation formula and then verified it in Abaqus. The simulation results showed that those plates after straightening meet the requirement of flatness. So, the research results provide a theoretical basis for development of a new plate straightening machine and formulation of intermesh schedule.
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- 2016
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12. STM studies of fusion of cholesterol suspensions and mixed 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)/cholesterol vesicles onto a Au(111) electrode surface
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Sek, Slawomir, Shimin Xu, Maohui Chen, Szymanski, Grzegorz, and Lipkowski, Jacek
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Cholesterol -- Chemical properties ,Choline -- Chemical properties ,Dielectric films -- Structure ,Dielectric films -- Composition ,Thin films -- Structure ,Thin films -- Composition ,Chemistry - Abstract
The structure of the film fabricated by fusion of cholesterol suspension and mixed dimyristoylphosphatidylcholine (DMPC) is characterized and the effect of cholesterol on the mechanism of vesicle fusion at the Au(111) electrode surface is determined.
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- 2008
13. Application of zirconia thermal barrier coating on the surface of pulling-straightening roller.
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Feng Zhang, Dengyue Sun, Jiuming Xie, Shimin Xu, Huagui Huang, Jun Li, Haitao Hou, and Jin Wu
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- 2017
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14. Self-assembly of phospholipid molecules at a Au(111) electrode surface
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Shimin Xu, Szymanski, Grzegorz, and Lipkowski, Jacek
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Surface chemistry -- Research ,Scanning tunneling microscopy -- Usage ,Gold -- Chemical properties ,Phospholipids -- Research ,Chemistry - Abstract
The first electrochemical scanning tunneling microscopy (EC-STM) studies of spreading 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC) vesicles into a film at a Au(111) electrode surface has been presented. With time, the molecules, reorient and the monolayer is transformed into a hemimicellar film.
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- 2004
15. Research on the production of biodiesel with Artemisia argyi.
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Teng Deng, Tao Sun, Shimin Xu, and Hui Ding
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- 2011
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16. Modeling and decoupling control simulation for a virtual coupling heater system.
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Anli Tao, Yunzhou Li, Rui Li, Shimin Xu, Lina Han, Junguo Liu, and Xiangzhong Li
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- 2010
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17. Synthesis of Polyfunctionalized Quinolines via the Sequence of Propargyl--Allenyl Isomerization and Aza-electrocyclization.
- Author
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Hongwei Zhou, Le Liu, and Shimin Xu
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- 2012
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18. Selecting the Optimum Predistillation Scheme for Heavy Crude Oils.
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Yanhong Wang, Yanjie Hou, Hong Gao, Jinsheng Sun, and Shimin Xu
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- 2011
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19. 3-Amino-7-phthalazinylbenzoisoxazoles as a Novel Class of Potent, Selective, and Orally Available Inhibitors of p38α Mitogen-Activated Protein Kinase.
- Author
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Liping H. Pettus, Shimin Xu, Guo-Qiang Cao, Partha P. Chakrabarti, Robert M. Rzasa, Kelvin Sham, Ryan P. Wurz, Dawei Zhang, Scott Middleton, Bradley Henkle, Matthew H. Plant, Christiaan J. M. Saris, Lisa Sherman, Lu Min Wong, David A. Powers, Yanyan Tudor, Violeta Yu, Matthew R. Lee, Rashid Syed, and Faye Hsieh
- Subjects
- *
RADIATION , *PHYSICS , *NUCLEAR energy , *MEDICAL technology - Abstract
The p38 mitogen-activated protein kinase (MAPK) is a central signaling molecule in many proinflammatory pathways, regulating the cellular response to a multitude of external stimuli including heat, ultraviolet radiation, osmotic shock, and a variety of cytokines especially interleukin-1β and tumor necrosis factor α. Thus, inhibitors of this enzyme are postulated to have significant therapeutic potential for the treatment of rheumatoid arthritis, inflammatory bowel disease, osteoporosis, and many other diseases where aberrant cytokine signaling is the driver of disease. Herein, we describe a novel class of 3-amino-7-phthalazinylbenzoisoxazole-based inhibitors. With relatively low molecular weight, these compounds are highly potent in enzyme and cell-based assays, with minimal protein shift in 50% human whole blood. Compound 3cwas efficacious (ED 50= 0.05 mg/kg) in the rat collagen induced arthritis (CIA) model. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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20. Discovery of Highly Selective and Potent p38 Inhibitors Based on a Phthalazine Scaffold.
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Brad Herberich, Guo-Qiang Cao, Partha P. Chakrabarti, James R. Falsey, Liping Pettus, Robert M. Rzasa, Anthony B. Reed, Andreas Reichelt, Kelvin Sham, Maya Thaman, Ryan P. Wurz, Shimin Xu, Dawei Zhang, Faye Hsieh, Matthew R. Lee, Rashid Syed, Vivian Li, David Grosfeld, Matthew H. Plant, and Bradley Henkle
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- 2008
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21. Optimizing Conditions for the Purification of Linoleic Acid from Sunflower Oil by Urea Complex Fractionation.
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Mingyi Wu, Hui Ding, Song Wang, and Shimin Xu
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LINOLEIC acid ,SUNFLOWER seed oil ,ALCOHOL ,UREA ,CRYSTALLIZATION ,FATTY acids - Abstract
The separation and purification of linoleic acid (LA) from sunflower seed oil by urea complex fractionation was studied. Crystallization reaction conditions of urea inclusion were optimized using the response surface method, and the optimal model was developed. Using the linear weighting method of the fitting model for optimization, the optimal balance between the purity and the recovery of LA was obtained. Under optimal conditions, the purity of LA was 87.8%, and the recovery was 83.4% at a urea-to-fatty acids ratio (w/w) of 0.94, 95% ethanol-tourea (v/w) of 5.00, a crystallization temperature of 18.0 °C, and a crystallization time of 5.0 h. Verification results revealed that the predicted values from these models were reasonably close to the experimentally observed values. [ABSTRACT FROM AUTHOR]
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- 2008
- Full Text
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22. Electric-Field-Driven Surface Aggregation of a Model Zwitterionic Surfactant.
- Author
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Shimin Xu, Maohui Chen, Ewa Cholewa, Grzegorz Szymanski, and Jacek Lipkowski
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- *
SURFACE active agents , *SOLUTION (Chemistry) , *COLLOIDS , *AMORPHOUS substances - Abstract
Electrochemical measurements, atomic force microscopy, and scanning tunneling microscopy have been combined to describe the electric-field-controlled surface aggregation of N-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (DDAPS), a model zwitterionic surfactant, at a Au(111) electrode surface. At concentrations below the critical micelle concentration (CMC), the monomer adsorbs and aggregates at the surface. The charge on the metal (M) controls the orientation of adsorbed molecules and consequently the film structure. At high negative (M< −5 C cm-2) charge densities, a spongy, disordered film is formed in which the polar heads are turned toward the solution. At high positive (M> 5 C cm-2) charge densities, a planar film with “blisters” is observed with the polar heads of DDAPS turned to the metal. Hemicylindrical aggregates are observed in the intermediate charge density range (−5 < M< 5 C cm-2). At bulk concentrations higher than the CMC, micelles adsorb and the structure of these films is controlled by the fusion of the adsorbed micelles. STM and AFM images provided direct visualization of this field-driven surface aggregation of the zwitterionic surfactant. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
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