118 results on '"Yang, Dong"'
Search Results
52. Influence of In Situ Pyrolysis on the Evolution of Pore Structure of Oil Shale.
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Liu, Zhijun, Yang, Dong, Hu, Yaoqing, Zhang, Junwen, Shao, Jixi, Song, Su, and Kang, Zhiqin
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SHALE oils , *NITROGEN , *FOSSIL fuels , *NONMETALS , *HEAT - Abstract
The evolution of pore structure during in situ underground exploitation of oil shale directly affects the diffusion and permeability of pyrolysis products. In this study, on the basis of mineral analysis and thermogravimetric results, in combination with the low-pressure nitrogen adsorption (LPNA) and mercury intrusion porosimetry (MIP) technique, the evolution of pore structure from 23 to 650 °C is quantitatively analyzed by simulating in situ pyrolysis under pressure and temperature conditions. Furthermore, based on the experimental results, we analyze the mechanism of pore structure evolution. The results show the following: (1) The organic matter of Fushun oil shale has a degradation stage in the temperature range of 350–540 °C, and there is no obvious temperature gradient between decomposition of kerogen and the secondary decomposition of bitumen. The thermal response mechanisms of organic matter and minerals are different in each temperature stage, and influence the change of pore structure. (2) Significant changes occur in pore shape at 350 °C, where thermal decomposition of kerogen begins. The ink-bottle pores are dominant when the temperature is less than 350 °C, whereas slit pores dominate when the temperature is greater than 350 °C. (3) The change in pore structure of oil shale is much less significant from 23 to 350 °C. The pore volume, porosity, and specific surface area (SSA) of samples increase rapidly with temperature varying from 350 to 600 °C. The variation of each parameter is dissimilated from 600 to 650 °C: the porosity and pore volume increases with a small gradient from 600 to 650 °C, and SSA decreases significantly. (4) The lithostatic pressure does not cause change in the evolution discipline of the pore structure, but the inhibitory effect on the pore development is significant. [ABSTRACT FROM AUTHOR]
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- 2018
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53. Fusion of LiDAR and Multispectral Data for Aboveground Biomass Estimation in Mountain Grassland.
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Chen, Ang, Wang, Xing, Zhang, Min, Guo, Jian, Xing, Xiaoyu, Yang, Dong, Zhang, Huilong, Hou, Zhiyan, Jia, Ze, and Yang, Xiuchun
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FOREST biomass , *BIOMASS estimation , *OPTICAL radar , *LIDAR , *STANDARD deviations , *GRASSLANDS , *PHOTOSYNTHETICALLY active radiation (PAR) - Abstract
Grassland aboveground biomass (AGB) is an important indicator for studying the change in grassland ecological quality and carbon cycle. The rapid development of high-resolution remote sensing and unmanned aerial vehicles (UAV) provides a new opportunity for accurate estimation of grassland AGB on the plot scale. In this study, the mountain grassland was taken as the research object. Using UAV Light Detection and Ranging (LiDAR) data and multispectral satellite images, the influence of topographic correction methods on AGB estimation was compared and a series of LiDAR metrics and vegetation indices were extracted. On this basis, a comprehensive indicator, the vegetation index-height-intensity model (VHI), was proposed to estimate AGB quickly. The results show that: (1) Among the four topographic correction methods, the Teillet regression has the best effect, and can effectively improve the accuracy of AGB estimation in mountain grassland. The correlation between corrected ratio vegetation index and AGB was the highest (correlation coefficient: 0.682). (2) Among the height and intensity metrics, median height and max intensity yielded the higher accuracy in estimating AGB, with Root Mean Square Error (RMSE) of 322 g/m2 and 333 g/m2, respectively. (3) The VHI integrated spectrum and LiDAR information, and its accuracy for AGB estimation for mountain grassland, was obviously better than other indicators, with an RMSE of 272 g/m2. We also found that the accuracy of VHI in univariate models was comparable to that of complex multivariate models such as stepwise regression, support vector machine, and random forest. This study provides a new approach for estimating grassland AGB with multi-source data. As a simple and effective indicator, VHI has shown strong application potential for grassland AGB estimating in mountainous areas, and can be further applied to grassland carbon cycle research and fine management. [ABSTRACT FROM AUTHOR]
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- 2023
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54. Large-Scale Land Deformation Monitoring over Southern California with Multi-Path SAR Data.
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Ao, Meng, Wang, Xiaotian, Sun, Ying, Wang, Fang, Zhang, Huanan, Wei, Lianhuan, Liu, Shanjun, and Yang, Dong
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SYNTHETIC aperture radar , *DEFORMATIONS (Mechanics) , *DEFORMATION of surfaces , *GROUNDWATER recharge - Abstract
Southern California, USA, has been suffering severe surface deformation due to its active crustal movement under the north–south compression of the Pacific Plate and North American Plate. Meanwhile, affected by groundwater extraction and recharge, oil exploitation, surface subsidence, uplift, and seasonal deformation occur commonly in this region. In this paper, multi-path SAR datasets were collected to investigate and monitor surface deformation in Southern California. The unified simultaneous least squares (USLS) approach is applied to remove the deformation discontinuity between adjacent SAR image paths. Multiple deformation patterns of structural faults, groundwater withdrawal, and oil exploitation are observed with the interferometric synthetic aperture radar (InSAR) technique. The InSAR-derived results were validated with GPS monitoring data. The correlations between land deformation and groundwater withdrawal, faults, and precipitation were intensively analyzed, finding out and mastering the magnitude and characteristics of ground deformation in Southern California. [ABSTRACT FROM AUTHOR]
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- 2023
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55. Experimental Research on the Flow and Heat Transfer Characteristics of Subcritical and Supercritical Water in the Vertical Upward Smooth and Rifled Tubes.
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Du, Xiaocheng, Li, Weiteng, Zhang, Xirong, Chen, Jingrong, Chen, Tingyu, and Yang, Dong
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SUPERCRITICAL water , *NUCLEATE boiling , *HEAT transfer , *HEAT transfer coefficient , *HEAT flux , *TUBES - Abstract
Experiments were conducted to investigate the heat transfer and flow characteristics of the vertical upward smooth and rifled tubes from subcritical to supercritical pressure. The distributions of wall temperature and heat transfer coefficient (HTC) were obtained, and the HTC correlations and friction resistance coefficient correlations were fitted with experimental data. In addition, the influences of heat flux and type of tube on heat transfer performance were analyzed. The research shows that heat flux has different influences on the heat transfer characteristics under different pressures. The increase in heat flux improves the heat transfer characteristics in the nucleate boiling region, yet it leads to the advance in heat transfer deterioration. However, for supercritical water, the increase in heat flux reduces the heat transfer ability. In addition, using the rifled tube not only improves the heat transfer performance, but also inhibits the occurrence of heat transfer deterioration. The fitted correlations have great predictive ability for the heat transfer coefficient and friction resistance coefficient, and the average relative fitting errors are limited to 20%. [ABSTRACT FROM AUTHOR]
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- 2022
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56. Alcohol Induces Zebrafish Skeletal Muscle Atrophy through HMGB1/TLR4/NF-κB Signaling.
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Wen, Wei, Sun, Chenchen, Chen, Zhanglin, Yang, Dong, Zhou, Zuoqiong, Peng, Xiyang, and Tang, Changfa
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MUSCULAR atrophy , *SKELETAL muscle , *BRACHYDANIO , *ALCOHOL drinking , *ALCOHOL , *GENE expression - Abstract
Excessive alcohol consumption can cause alcoholic myopathy, but the molecular mechanism is still unclear. In this study, zebrafish were exposed to 0.5% alcohol for eight weeks to investigate the effect of alcohol on skeletal muscle and its molecular mechanism. The results showed that the body length, body weight, cross-sectional area of the skeletal muscle fibers, Ucrit, and MO2max of the zebrafish were significantly decreased after alcohol exposure. The expression of markers of skeletal muscle atrophy and autophagy was increased, and the expression of P62 was significantly reduced. The content of ROS, the mRNA expression of sod1 and sod2, and the protein expression of Nox2 were significantly increased. In addition, we found that the inflammatory factors Il1β and Tnfα were significantly enriched in skeletal muscle, and the expression of the HMGB1/TLR4/NF-κB signaling axis was also significantly increased. In summary, in this study, we established a zebrafish model of alcohol-induced skeletal muscle atrophy and further elucidated its pathogenesis. [ABSTRACT FROM AUTHOR]
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- 2022
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57. A Study on Impact Force Detection Method Based on Piezoelectric Sensing.
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Liu, Jianli, Hei, Chuang, Luo, Mingzhang, Yang, Dong, Sun, Changhe, and Feng, Ankang
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TRANSIENTS (Dynamics) , *STRESS waves , *FINITE element method , *IMPACT response , *IMPACT (Mechanics) , *STRUCTURAL engineering - Abstract
Impact force refers to a transient phenomenon with a very short-acting time, but a large impulse. Therefore, the detection of impact vibration is critical for the reliability, stability, and overall life of mechanical parts. Accordingly, this paper proposes a method to indirectly characterize the impact force by using an impact stress wave. The LS-DYNA software is utilized to establish the model of a ball impacting the steel plate, and the impact force of the ball and the impact response of the detection point are obtained through explicit dynamic finite element analysis. In addition, on this basis, a correspondence between the impact force and the impact response is established, and finally, an experimental platform for impact force detection is built for experimental testing. The results obtained by the finite element method are in good agreement with the experimental measurement results, and it can be inferred that the detected piezoelectric signal can be used to characterize the impact force. The method proposed herein can guide the impact resistance design and safety assessment of structures in actual engineering applications. [ABSTRACT FROM AUTHOR]
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- 2022
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58. Predictive Scale for Amyloid PET Positivity Based on Clinical and MRI Variables in Patients with Amnestic Mild Cognitive Impairment.
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Chun, Min Young, Kim, Geon Ha, Park, Hee Kyung, Yang, Dong Won, Kim, SangYun, Choi, Seong Hye, and Jeong, Jee Hyang
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AMNESTIC mild cognitive impairment , *MILD cognitive impairment , *POSITRON emission tomography , *AMYLOID , *MAGNETIC resonance imaging , *ALZHEIMER'S disease - Abstract
The presence of amyloid-β (Aβ) deposition is considered important in patients with amnestic mild cognitive impairment (aMCI), since they can progress to Alzheimer's disease dementia. Amyloid positron emission tomography (PET) has been used for detecting Aβ deposition, but its high cost is a significant barrier for clinical usage. Therefore, we aimed to develop a new predictive scale for amyloid PET positivity using easily accessible tools. Overall, 161 aMCI patients were recruited from six memory clinics and underwent neuropsychological tests, brain magnetic resonance imaging (MRI), apolipoprotein E (APOE) genotype testing, and amyloid PET. Among the potential predictors, verbal and visual memory tests, medial temporal lobe atrophy, APOE genotype, and age showed significant differences between the Aβ-positive and Aβ-negative groups and were combined to make a model for predicting amyloid PET positivity with the area under the curve (AUC) of 0.856. Based on the best model, we developed the new predictive scale comprising integers, which had an optimal cutoff score ≥ 3. The new predictive scale was validated in another cohort of 98 participants and showed a good performance with AUC of 0.835. This new predictive scale with accessible variables may be useful for predicting Aβ positivity in aMCI patients in clinical practice. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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59. Investigation on the Fracture-Pore Evolution and Percolation Characteristics of Oil Shale under Different Temperatures.
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Tang, Haibo, Zhao, Yangsheng, Kang, Zhiqin, Lv, Zhaoxing, Yang, Dong, and Wang, Kun
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OIL shales , *SHALE oils , *POROSITY , *IN situ processing (Mining) , *PERCOLATION , *PYROLYTIC graphite - Abstract
It is well known that underground in situ pyrolysis technology for oil shale production is a promising field. In the in situ modification mining process, the permeability property of a shale matrix has a great effect on the transport capacity of pyrolytic products. For oil shale undergoing pyrolysis, the changes of internal structure (fracture and pore space) have a considerable influence on the permeability network which further affects the migration of hydrocarbon products. In this study, based on an oil shale retorting experiment performed under different temperatures (20 °C, 100 °C, 200 °C, 300 °C, 325 °C, 350 °C, 375 °C, 400 °C, 425 °C, 450 °C, 475 °C, 500 °C, 525 °C, 550 °C, 575 °C, 600 °C), an investigation on the distribution characteristics of the fractures was conducted using micro-CT technology. Meanwhile, mercury injection porosimetry was used to characterize the pore structure of the oil shale samples under different temperatures. Finally, a fracture-pore dual medium model was constructed to calculate the percolation probability to quantitatively describe the permeability variation of oil shale with temperature. The test results indicated that the higher the temperature, the larger were the pore spaces. The increase in pore volume due to pyrolysis temperatures mainly affected the pores ranging from 10 nm to 100 nm and occurred in the specific temperature range (400 °C to 425 °C). Additionally, CT images show that the fracture morphology varied with increasing temperature and the number and length of fractures at different temperatures were in great accordance with the fractal law statistically. On the other hand, simulation of the percolation probabilities discovered that in a single pore media model over the whole range of tested temperatures they were too low to exceed the threshold. In contrast, in the dual medium model, the theoretical threshold of 31.16% was exceeded when the temperature reached 350 °C. Moreover, the results demonstrated that fractures dominated the seepage channel and had more significant effects on the permeability of oil shale. What has been done in this study will provide some guidance for the in situ fluidization mining of oil shale. [ABSTRACT FROM AUTHOR]
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- 2022
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60. Hyperspectral Image Mixed Noise Removal Using a Subspace Projection Attention and Residual Channel Attention Network.
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Sun, Hezhi, Zheng, Ke, Liu, Ming, Li, Chao, Yang, Dong, and Li, Jindong
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ORTHOGRAPHIC projection , *NOISE , *LEARNING strategies , *IMAGE denoising , *ARTIFICIAL neural networks , *HYPERSPECTRAL imaging systems - Abstract
Although the existing deep-learning-based hyperspectral image (HSI) denoising methods have achieved tremendous success, recovering high-quality HSIs in complex scenes that contain mixed noise is still challenging. Besides, these methods have not fully explored the local and global spatial–spectral information of HSIs. To address the above issues, a novel HSI mixed noise removal network called subspace projection attention and residual channel attention network (SPARCA-Net) is proposed. Specifically, we propose an orthogonal subspace projection attention (OSPA) module to adaptively learn to generate bases of the signal subspace and project the input into such space to remove noise. By leveraging the local and global spatial relations, OSPA is able to reconstruct the local structure of the feature maps more precisely. We further propose a residual channel attention (RCA) module to emphasize the interdependence between feature maps and exploit the global channel correlation of them, which could enhance the channel-wise adaptive learning. In addition, multiscale joint spatial–spectral input and residual learning strategies are employed to capture multiscale spatial–spectral features and reduce the degradation problem, respectively. Synthetic and real HSI data experiments demonstrated that the proposed HSI denoising network outperforms many of the advanced methods in both quantitative and qualitative assessments. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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61. Survival in Korean Patients with Frontotemporal Dementia Syndrome: Association with Behavioral Features and Parkinsonism.
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Jung, Na-Yeon, Park, Kee Hyung, Seo, Sang Won, Kim, Hee Jin, Roh, Jee Hoon, Lee, Jae-Hong, Park, Kyung Won, Kwon, Jay C., Jeong, Jee Hyang, Yoon, Soo Jin, Kim, Byeong C., Park, Young Ho, Kim, SangYun, Jang, Jae-Won, Youn, Young Chul, Yang, Dong Won, Choi, Seong Hye, Na, Duk L., and Kim, Eun-Joo
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FRONTOTEMPORAL dementia , *KOREANS , *PROPORTIONAL hazards models , *PARKINSONIAN disorders , *PARKINSON'S disease , *DYSARTHRIA - Abstract
We investigated the survival time of each clinical syndrome of frontotemporal dementia (FTD) and the impacts of behavioral and motor features on survival of FTD. A total of 216 patients with FTD [82 behavioral variant FTD (bvFTD), 78 semantic variant primary progressive aphasia (svPPA), 43 non-fluent/agrammatic variant PPA (nfvPPA), 13 FTD-motor neuron disease (MND)] were enrolled from 16 centers across Korea. Behaviors and parkinsonism were assessed using the Frontal Behavioral Inventory and Unified Parkinson's Disease Rating Scale Part III, respectively. The Kaplan–Meier method was used for the survival analysis and the Cox proportional hazards model was applied for analysis of the effect of behavioral and motor symptoms on survival, after controlling vascular risk factors and cancer. An overall median survival of FTD was 12.1 years. The survival time from onset was shortest for FTD-MND and longest for svPPA. The median survival time of patients with bvFTD was unavailable but likely comparable to that of patients with nfvPPA. In the bvFTD group, negative behavioral symptoms and akinetic rigidity were significantly associated with survival. In the nfvPPA group, the presence of dysarthria had a negative impact on survival. These findings provide useful information to clinicians planning for care. [ABSTRACT FROM AUTHOR]
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- 2022
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62. In Situ Stability of Anthocyanins in Lycium ruthenicum Murray.
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Wang, Yanping, Fu, Jingxian, and Yang, Dong
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ANTHOCYANINS , *ANTHOCYANIDINS , *CYANIDIN , *LOW temperatures , *FREEZE-drying , *GLUCOSE - Abstract
In this research, the effects of drying method, storage temperature, and color protector glucose on anthocyanin preservation in the Lycium ruthenicum Murr. fruit were studied. Compared with hot-air drying, vacuum freeze-drying preserved about 5.8-fold more anthocyanins. The half-life of anthocyanins in the freeze-dried fruit samples with glucose was 3.6 days, 1.8 days, and 1.7 days at 4 °C, 20 °C, and 37 °C, respectively. On the other hand, the half-life values without glucose addition were 2.2 days, 2.3 days, and 2.1 days at each temperature, respectively, indicating that glucose protected anthocyanins at low temperature. The composition and contents of anthocyanins and anthocyanidins in the freeze-dried Lycium ruthenicum Murr., stored for 20 days, were investigated with a HPLC-MS/MS setup. It was found that most anthocyanidins in Lycium ruthenicum Murr. are linked with coumaroyl glucose to form anthocyanins, while glycosylated and acetyl-glycosylated anthocyanins were also detected. Five anthocyanidins were detected: delphinidin, cyanidin, petunidin, malvidin, and peonidin, and delphinidin accounts for about half of the total amount of anthocyanidins. It is much more economic to conserve anthocyanins in situ with freeze-drying methods and to store the fruits at low temperatures with glucose. [ABSTRACT FROM AUTHOR]
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- 2021
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63. Contributions of the C-Terminal Helix to the Structural Stability of a Hyperthermophilic Fe-Superoxide Dismutase (TcSOD).
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Sha Wang, Yong-Bin Yan, and Zhi-Yang Dong
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HELIX (Mollusks) , *STRUCTURAL stability , *THERMOTHERAPY , *MOLECULAR dynamics , *SUPEROXIDE dismutase , *PROTEIN engineering , *PROTEIN folding , *GUANIDINE , *MONOMERS - Abstract
Hyperthermophilic superoxide dismutases (SODs) are of particular interest due to their potential industrial importance and scientific merit in studying the molecular mechanisms of protein folding and stability. Compared to the mesophilic SODs, the hyperthermostable Fe-SODs (TcSOD and ApSOD) have an extended C-terminal helix, which forms an additional ion-pairing network. In this research, the role of the extended C-terminus in the structural stability of TcSOD was studied by investigating the properties of two deletion mutants. The results indicated that the ion-pairing network at the C-terminus had limited contributions to the stability of TcSOD against heat- and GdnHClinduced inactivation. The intactness of the C-terminal helix had dissimilar impact on the two stages of TcSOD unfolding induced by guanidinium chloride. The mutations slightly decreased the Gibbs free energy of the dissociation of the tetrameric enzymes, while greatly affected the stability of the molten globule-like intermediate. These results suggested that the additional ion-pairing network mainly enhanced the structural stability of TcSOD by stabilizing the monomers. [ABSTRACT FROM AUTHOR]
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- 2009
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64. An Easy and Economical Way to Produce a Three-Dimensional Bone Phantom in a Dog with Antebrachial Deformities.
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Lee, Hee-Ryung, Adam, Gareeballah Osman, Yang, Dong Kwon, Tungalag, Tsendsuren, Lee, Sei-Jin, Kim, Jin-Shang, Kang, Hyung-Sub, Kim, Shang-Jin, and Kim, Nam Soo
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BONES , *HUMAN abnormalities , *3-D printers , *DOGS , *IMAGING phantoms , *FREEWARE (Computer software) - Abstract
Simple Summary: Accurate planning, for corrective surgeries in case of bone cutting, is necessary to obtain a precise coordination of the skeleton and to achieve the owner's satisfaction. The present experiment displays a simple and cost-effective technique for surgical planning, utilizing a 3-D bone phantom model in a dog with foreleg deformity. 3-D surgical planning for restorative osteotomy is costly and time-consuming because surgeons need to be helped from commercial companies to get 3-D printed bones. However, practitioners can save time and keep the cost to a minimum by utilizing free software and establishing their 3-D printers locally. Surgical planning for the corrective osteotomy of antebrachial growth deformities (AGD) is challenging for several reasons (the nature of the biapical or multiapical conformational abnormalities and lack of a reference value for the specific breed). Pre-operative planning challenges include: a definite description of the position of the center of rotation of angulation (CORA) and proper positioning of the osteotomies applicable to the CORA. In the present study, we demonstrated an accurate and reproducible bone-cutting technique using patient-specific instrumentations (PSI) 3-D technology. The results of the location precision showed that, by using PSIs, the surgeons were able to accurately replicate preoperative resection planning. PSI results also indicate that PSI technology provides a smaller standard deviation than the freehand method. PSI technology performed in the distal radial angular deformity may provide good cutting accuracy. In conclusion, the PSI technology may improve bone-cutting accuracy during corrective osteotomy by providing clinically acceptable margins. [ABSTRACT FROM AUTHOR]
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- 2020
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65. RMLNet—A Reliable Wireless Network for a Multiarea TDOA-Based Localization System.
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Xue, Yuan, Su, Wei, Yang, Dong, Wang, Hongchao, and Zhang, Weiting
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WIRELESS localization , *POWER transmission , *WIRELESS communications , *ACCESS control - Abstract
Ultrawideband (UWB) wireless communication is a promising spread-spectrum technology for accurate localization among devices characterized by a low transmission power, a high rate and immunity to multipath propagation. The accurately of the clock synchronization algorithm and the time-difference-of-arrival (TDOA) localization algorithm provide precise position information of mobile nodes with centimeter-level accuracy for the UWB localization system. However, the reliability of target node localization for multi-area localization remains a subject of research. Especially for dynamic and harsh indoor environments, an effective scheme among competing target nodes for localization due to the scarcity of radio resources remains a challenge. In this paper, we present RMLNet, an approach focus on the medium access control (MAC) layer, which guarantees general localization application reliability on multi-area localization. Specifically, the design requires specific and optimized solutions for managing and coordinating multiple anchor nodes. In addition, an approach for target area determination is proposed, which can approximately determine the region of the target node by the received signal strength indication (RSSI), to support RMLNet. Furthermore, we implement the system to estimate the localization of the target node and evaluate its performance in practice. Experiments and simulations show that RMLNet can achieve localization application reliability multi-area localization with a better localization performance of competing target nodes. [ABSTRACT FROM AUTHOR]
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- 2019
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66. Efficient Resource Scheduling for Multipath Retransmission over Industrial WSAN Systems.
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Wang, Hongchao, Ma, Jian, Yang, Dong, and Gidlund, Mikael
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WIRELESS communications , *WIRELESS sensor networks , *COMPUTER scheduling - Abstract
With recent adoption of Wireless Sensor-Actuator Networks (WSANs) in industrial automation, wireless control systems have emerged as a frontier of industrial networks. Hence, it has been shown that existing standards and researches concentrate on the reliability and real-time performance of WSANs. The multipath retransmission scheme with multiple channels is a key approach to guarantee the deterministic wireless communication. However, the efficiency of resource scheduling is seldom considered in applications with diverse data sampling rates. In this paper, we propose an efficient resources scheduling algorithm for multipath retransmission in WSANs. The objective of our algorithm is to improve efficiency and schedulability for the use of slot and channel resources. In detail, the proposed algorithm uses the approaches of CCA (clear channel assessment)-Embedded slot and Multiple sinks with Rate Monotonic scheme (CEM-RM) to decrease the number of collisions. We have simulated and implemented our algorithm in hardware and verified its performance in a real industrial environment. The achieved results show that the proposed algorithm significantly improves the schedulability without trading off reliability and real-time performance. [ABSTRACT FROM AUTHOR]
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- 2019
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67. CA-CWA: Channel-Aware Contention Window Adaption in IEEE 802.11ah for Soft Real-Time Industrial Applications.
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Cheng, Yujun, Zhou, Huachun, and Yang, Dong
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WIRELESS LANs , *INDUSTRIAL applications - Abstract
In 2016, the IEEE task group ah (TGah) released a new standard called IEEE 802.11ah, and industrial Internet of Things (IoT) is one of its typical use cases. The restricted access window (RAW) is one of the core MAC mechanisms of IEEE 802.11ah, which aims to address the collision problem in the dense wireless networks. However, in each RAW period, stations still need to contend for the channel by Distributed Coordination Function and Enhanced Distributed Channel Access (DCF/EDCA), which cannot meet the real-time requirements of most industrial applications. In this paper, we propose a channel-aware contention window adaption (CA-CWA) algorithm. The algorithm dynamically adapts the contention window based on the channel status with an external interference discrimination ability, and improves the real-time performance of the IEEE 802.11ah. To validate the real-time performance of CA-CWA, we compared CA-CWA with two other backoff algorithms with an NS-3 simulator. The results illustrate that CA-CWA has better performance than the other two algorithms in terms of packet loss rate and average delay. Compared with the other two algorithms, CA-CWA is able to support industrial applications with higher deadline constraints under the same channel conditions in IEEE 802.11ah. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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68. Characterization of the Lipidomic Profile of Human Coronavirus-Infected Cells: Implications for Lipid Metabolism Remodeling upon Coronavirus Replication.
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Yan, Bingpeng, Chu, Hin, Yang, Dong, Sze, Kong-Hung, Lai, Pok-Man, Yuan, Shuofeng, Shuai, Huiping, Wang, Yixin, Kao, Richard Yi-Tsun, Chan, Jasper Fuk-Woo, and Yuen, Kwok-Yung
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CORONAVIRUS diseases , *CORONAVIRUSES , *LIPID metabolism , *MICROBIAL virulence , *HIGH performance liquid chromatography , *ARACHIDONIC acid - Abstract
Lipids play numerous indispensable cellular functions and are involved in multiple steps in the replication cycle of viruses. Infections by human-pathogenic coronaviruses result in diverse clinical outcomes, ranging from self-limiting flu-like symptoms to severe pneumonia with extrapulmonary manifestations. Understanding how cellular lipids may modulate the pathogenicity of human-pathogenic coronaviruses remains poor. To this end, we utilized the human coronavirus 229E (HCoV-229E) as a model coronavirus to comprehensively characterize the host cell lipid response upon coronavirus infection with an ultra-high performance liquid chromatography-mass spectrometry (UPLC–MS)-based lipidomics approach. Our results revealed that glycerophospholipids and fatty acids (FAs) were significantly elevated in the HCoV-229E-infected cells and the linoleic acid (LA) to arachidonic acid (AA) metabolism axis was markedly perturbed upon HCoV-229E infection. Interestingly, exogenous supplement of LA or AA in HCoV-229E-infected cells significantly suppressed HCoV-229E virus replication. Importantly, the inhibitory effect of LA and AA on virus replication was also conserved for the highly pathogenic Middle East respiratory syndrome coronavirus (MERS-CoV). Taken together, our study demonstrated that host lipid metabolic remodeling was significantly associated with human-pathogenic coronavirus propagation. Our data further suggested that lipid metabolism regulation would be a common and druggable target for coronavirus infections. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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69. Permeability Evolution of Pyrolytically-Fractured Oil Shale under In Situ Conditions.
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Dong, Fuke, Feng, Zijun, Yang, Dong, Zhao, Yangsheng, and Elsworth, Derek
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PYROLYSIS , *OIL shales , *PERMEABILITY , *TEMPERATURE , *CHEMICAL reactions - Abstract
In-situ injection of steam for heating of the subsurface is an efficient method for the recovery of oil and gas from oil shale where permeability typically evolves with temperature. We report measurements on Jimusar oil shales (Xinjiang, China) at stepped temperatures to 600 °C and under recreated in situ triaxial stresses (15 MPa) and recover permeability evolution with temperature and stress. Initial very low permeability evolves with the temperature above an initial threshold temperature at high rate before reaching a plateau in permeability above a peak temperature. The threshold temperature triggering the initial rapid rise in permeability is a function of triaxial stresses. For Jimusar oil shale, this threshold temperature ranges from 200 °C to 250 °C for burial depths of 500 m and from 350 °C to 400 °C for burial depths of 1000 m. This rapid rise in permeability correlates with the vigor of pyrolysis and directly scales with the production rate of pyrolysis-derived gas production. The permeability increases with temperature to a plateau in peak permeability that occurs at a peak-permeability temperature. This peak temperature is insensitive to stress and is in the range 450 °C to 500 °C for all Jimusar samples. Pyrolysis plays an important role in the stage of rapid permeability evolution with this effect stopping once pyrolysis is essentially complete. At these ultimate high temperatures, permeability exhibits little reduction due to stress and remains elevated due to the vigor of the pyrolysis. These results effectively demonstrate that oil shale may be transformed by pyrolysis from a tight porous medium into highly permeable medium and that oil and gas may be readily recovered from it. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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70. Dietary Total Prenylflavonoids from the Fruits of Psoralea corylifolia L. Prevents Age-Related Cognitive Deficits and Down-Regulates Alzheimer's Markers in SAMP8 Mice.
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Chen, Zhi-Jing, Yang, Yan-Fang, Zhang, Ying-Tao, and Yang, Dong-Hui
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PSORALEA , *ALZHEIMER'S disease , *POPULATION aging , *MAZE tests , *THERAPEUTIC use of cytokines , *RESVERATROL , *THERAPEUTICS - Abstract
Alzheimer's disease (AD) is a serious threat for the aging society. In this study, we examined the preventive effect of the total prenylflavonoids (TPFB) prepared from the dried fruits of Psoralea corylifolia L., using an age-related AD mouse model SAMP8. We found that long-term dietary TPFB at 50 mg/kg·day significantly improved cognitive performance of the SAMP8 mice in Morris water maze tests, similar to 150 mg/kg·day of resveratrol, a popular neuro-protective compound. Furthermore, TPFB treatment showed significant improvements in various AD markers in SAMP8 brains, which were restored to near control levels of the normal mice, SAMR1. TPFB significantly reduced the level of amyloid β-peptide 42 (Aβ42), inhibited hyperphosphorylation of the microtubule-associated protein Tau, induced phosphorylation of Ser9 of the glycogen synthase kinase 3β (GSK-3β), and decreased the expression of the proinflammatory cytokines TNFα, IL-6, and IL-1β. Finally, TPFB also markedly reduced the level of serum derivatives of reactive oxygen metabolites (d-ROMs), a biomarker of oxidative stress in vivo. These results showed that dietary TPFB could effectively prevent age-related cognitive deficits and AD-like neurobiochemical changes, and may have a potential role in the prevention of Alzheimer's disease. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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71. Evaluation of Conservation Voltage Reduction with Analytic Hierarchy Process: A Decision Support Framework in Grid Operations Planning.
- Author
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Kyungsung An, Hao Jan Liu, Hao Zhu, Zhao Yang Dong, and Kyeon Hur
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ELECTRIC potential , *ANALYTIC hierarchy process , *ELECTRIC network topology , *ELECTRIC power , *ELECTRIC substations - Abstract
This paper presents a systematic framework to evaluate the performance of conservation voltage reduction (CVR) by determining suitable substations for CVR in operations planning. Existing CVR planning practice generally only focuses on the energy saving aspect without taking other underlying attributes into account, i.e., network topology and reduced voltage effects on other substations. To secure the desired operating reserve and avoid any adverse impacts, these attributes should be considered for implementing CVR more effectively. This research develops a practical decision-making framework based on the analytic hierarchy process (AHP) to quantify several of the aforementioned attributes. Candidate substations for CVR deployment are prioritized such that performances are compared in terms of power transfer distribution factor (PTDF), voltage sensitivity factor (VSF), and CVR factor. In addition, to meet a specified reserve requirement, an integer programming approach is adopted to select potential substations for CVR implementations. Case studies for a Korean electric power system under diverse operating conditions are performed to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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72. Inverse Aerodynamic Optimization Considering Impacts of Design Tip Speed Ratio for Variable-Speed Wind Turbines.
- Author
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Zhiqiang Yang, Minghui Yin, Yan Xu, Yun Zou, Zhao Yang Dong, and Qian Zhou
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WIND turbines , *ROTORS , *AERODYNAMICS , *WIND power , *SIMULATION methods & models - Abstract
Because of the slow dynamic behavior of the large-inertia wind turbine rotor, variable-speed wind turbines (VSWTs) are actually unable to keep operating at the design tip speed ratio (TSR) during the maximum power point tracking (MPPT) process. Moreover, it has been pointed out that although a larger design TSR can increase the maximum power coefficient, it also greatly prolongs the MPPT process of VSWTs. Consequently, turbines spend more time operating at the off-design TSRs and the wind energy capture efficiency is decreased. Therefore, in the inverse aerodynamic design of VSWTs, the static aerodynamic performance (i.e., the maximum power coefficient) and the dynamic process of MPPT should be comprehensively modeled for determining an appropriate design TSR. In this paper, based on the inverse design method, an aerodynamic optimization method for VSWTs, fully considering the impacts of the design TSR on the static and dynamic behavior of wind turbines is proposed. In this method, to achieve higher wind energy production, the design TSR, chord length and twist angle are jointly optimized, which is structurally different from the conventional separated design procedure. Finally, the effectiveness of the proposed method is validated by simulation results based on the Bladed software. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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73. A Multi-Point Method Considering the Maximum Power Point Tracking Dynamic Process for Aerodynamic Optimization of Variable-Speed Wind Turbine Blades.
- Author
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Zhiqiang Yang, Minghui Yin, Yan Xu, Zhengyang Zhang, Yun Zou, and Zhao Yang Dong
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MAXIMUM power point trackers , *AERODYNAMICS , *VARIABLE speed generators , *WIND turbine blades , *CLOSED loop systems , *TURBULENCE - Abstract
Due to the dynamic process of maximum power point tracking (MPPT) caused by turbulence and large rotor inertia, variable-speed wind turbines (VSWTs) cannot maintain the optimal tip speed ratio (TSR) from cut-in wind speed up to the rated speed. Therefore, in order to increase the total captured wind energy, the existing aerodynamic design for VSWT blades, which only focuses on performance improvement at a single TSR, needs to be improved to a multi-point design. In this paper, based on a closed-loop system of VSWTs, including turbulent wind, rotor, drive train and MPPT controller, the distribution of operational TSR and its description based on inflow wind energy are investigated. Moreover, a multi-point method considering the MPPT dynamic process for the aerodynamic optimization of VSWT blades is proposed. In the proposed method, the distribution of operational TSR is obtained through a dynamic simulation of the closed-loop system under a specific turbulent wind, and accordingly the multiple design TSRs and the corresponding weighting coefficients in the objective function are determined. Finally, using the blade of a National Renewable Energy Laboratory (NREL) 1.5 MW wind turbine as the baseline, the proposed method is compared with the conventional single-point optimization method using the commercial software Bladed. Simulation results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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74. Sensitivity of Green-Up Date to Meteorological Indicators in Hulun Buir Grasslands of China.
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Guo, Jian, Yang, Xiuchun, Jiang, Weiguo, Chen, Fan, Zhang, Min, Xing, Xiaoyu, Chen, Ang, Yun, Peng, Jiang, Liwei, Yang, Dong, and Xu, Bin
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MOUNTAIN meadows , *GRASSLAND soils , *STEPPES , *MEADOWS , *CLIMATE change , *GRASSLANDS - Abstract
Temperature and precipitation are considered to be the most important indicators affecting the green-up date. Sensitivity of the green-up date to temperature and precipitation is considered to be one of the key indicators to characterize the response of terrestrial ecosystems to climate change. We selected the main grassland types for analysis, including temperate steppe, temperate meadow steppe, upland meadow, and lowland meadow. This study investigates the variation in key meteorological indicators (daily maximum temperature (Tmax), daily minimum temperature (Tmin), and precipitation) between 2001 and 2018. We then examined the partial correlation and sensitivity of green-up date (GUD) to Tmax, Tmin, and precipitation. Our analysis indicated that the average GUD across the whole area was DOY 113. The mean GUD trend was −3.1 days/decade and the 25% region advanced significantly. Tmax and Tmin mainly showed a decreasing trend in winter (p > 0.05). In spring, Tmax mainly showed an increasing trend (p > 0.05) and Tmin a decreasing trend (p > 0.05). Precipitation showed no significant (p > 0.05) change trend and the trend range was ±10 mm/decade. For temperate steppe, the increase in Tmin in March promotes green-up (27.3%, the proportion of significant pixels), with a sensitivity of −0.17 days/°C. In addition, precipitation in April also promotes green-up (21.7%), with a sensitivity of −0.32 days/mm. The GUDs of temperate meadow steppe (73.9%), lowland meadow (65.9%), and upland meadow (22.1%) were mainly affected by Tmin in March, with sensitivities of −0.15 days/°C, −0.13 days/°C, and −0.14 days/°C, respectively. The results of this study reveal the response of vegetation to climate warming and contribute to improving the prediction of ecological changes as temperatures increase in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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75. Seismic Response of Resilient Bridges with SMA-Based Rocking ECC-Reinforced Piers.
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Li, Xiaogang, Chen, Ke, Chen, Ji, Li, Yi, and Yang, Dong
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SEISMIC response , *SHAPE memory alloys , *PIERS , *CEMENT composites , *REINFORCED concrete , *ENERGY dissipation - Abstract
Post-earthquake investigation shows that numerous reinforced concrete (RC) bridges were demolished because of large residual displacements. Improving the self-centering capability and hence resilience of these bridges located in earthquake-prone regions is essential. In this regard, a resilient bridge system incorporating engineered cementitious composites (ECC) reinforced piers and shape memory alloy (SMA) energy dissipation components, i.e., SMA washers, is proposed to enhance its resilience when subjected to strong earthquakes. This study commences with a detailed introduction of the resilient SMA-washer-based rocking bridge system with ECC-reinforced piers. Subsequently, a constitutive model of the ECC material is implemented into OpenSees and the constitutive model is validated by test data. The working principle and constitutive model of the SMA washers are also introduced. A series of dynamic analysis on the conventional and resilient rocking bridge systems with ECC-reinforced piers under a suite of ground motions at E1 and E2 earthquake levels are conducted. The analysis results indicate that the resilient rocking bridge system with ECC-reinforced piers has superior resilience and damage control capacities over the conventional one. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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76. Roles of the 2-Oxoglutarate-Dependent Dioxygenase Superfamily in the Flavonoid Pathway: A Review of the Functional Diversity of F3H, FNS I, FLS, and LDOX/ANS.
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Wang, Yueyue, Shi, Yufeng, Li, Kaiyuan, Yang, Dong, Liu, Nana, Zhang, Lingjie, Zhao, Lei, Zhang, Xinfu, Liu, Yajun, Gao, Liping, Xia, Tao, and Wang, Peiqiang
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PLANT adaptation , *PLANT metabolism , *CYANIDIN , *FLAVONES , *PROANTHOCYANIDINS , *PLANT proteins , *FLAVONOIDS - Abstract
The 2-oxoglutarate-dependent dioxygenase (2-OGD) superfamily is one of the largest protein families in plants. The main oxidation reactions they catalyze in plants are hydroxylation, desaturation, demethylation, epimerization, and halogenation. Four members of the 2-OGD superfamily, i.e., flavonone 3β-hydroxylase (F3H), flavones synthase I (FNS I), flavonol synthase (FLS), and anthocyanidin synthase (ANS)/leucoanthocyanidin dioxygenase (LDOX), are present in the flavonoid pathway, catalyzing hydroxylation and desaturation reactions. In this review, we summarize the recent research progress on these proteins, from the discovery of their enzymatic activity, to their functional verification, to the analysis of the response they mediate in plants towards adversity. Substrate diversity analysis indicated that F3H, FNS Ⅰ, ANS/LDOX, and FLS perform their respective dominant functions in the flavonoid pathway, despite the presence of functional redundancy among them. The phylogenetic tree classified two types of FNS Ⅰ, one mainly performing FNS activity, and the other, a new type of FNS present in angiosperms, mainly involved in C-5 hydroxylation of SA. Additionally, a new class of LDOXs is highlighted, which can catalyze the conversion of (+)-catechin to cyanidin, further influencing the starter and extension unit composition of proanthocyanidins (PAs). The systematical description of the functional diversity and evolutionary relationship among these enzymes can facilitate the understanding of their impacts on plant metabolism. On the other hand, it provides molecular genetic evidence of the chemical evolution of flavonoids from lower to higher plants, promoting plant adaptation to harsh environments. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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77. Exercise Intervention Mitigates Pathological Liver Changes in NAFLD Zebrafish by Activating SIRT1/AMPK/NRF2 Signaling.
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Zou, Yunyi, Chen, Zhanglin, Sun, Chenchen, Yang, Dong, Zhou, Zuoqiong, Peng, Xiyang, Zheng, Lan, and Tang, Changfa
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PATHOLOGICAL physiology , *NON-alcoholic fatty liver disease , *HIGH-fat diet , *BRACHYDANIO , *BCL genes , *REACTIVE oxygen species - Abstract
Non-alcoholic fatty liver disease (NAFLD) is a common disease that causes serious liver damage. Exercise is recognized as a non-pharmacological tool to improve the pathology of NAFLD. However, the antioxidative effects and mechanisms by which exercise ameliorates NAFLD remain unclear. The present study conducted exercise training on zebrafish during a 12-week high-fat feeding period to study the antioxidant effect of exercise on the liver. We found that swimming exercise decreased lipid accumulation and improved pathological changes in the liver of high-fat diet-fed zebrafish. Moreover, swimming alleviated NOX4-derived reactive oxygen species (ROS) overproduction and reduced methanedicarboxylic aldehyde (MDA) levels. We also examined the anti-apoptotic effects of swimming and found that it increased the expression of antiapoptotic factor bcl2 and decreased the expression of genes associated with apoptosis (caspase3, bax). Mechanistically, swimming intervention activated SIRT1/AMPK signaling-mediated lipid metabolism and inflammation as well as enhanced AKT and NRF2 activation and upregulated downstream antioxidant genes. In summary, exercise attenuates pathological changes in the liver induced by high-fat diets. The underlying mechanisms might be related to NRF2 and mediated by SIRT1/AMPK signaling. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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78. A Surveillance Endoscopy Strategy Based on Local Recurrence Rates after Colorectal Endoscopic Submucosal Dissection.
- Author
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Park, Jin Hwa, Yoon, Ji Young, Hwang, Sung Wook, Park, Sang Hyoung, Yang, Dong-Hoon, Ye, Byong Duk, Myung, Seung-Jae, Yang, Suk-Kyun, and Byeon, Jeong-Sik
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COLORECTAL cancer , *COLON tumors , *ENDOSCOPY , *BENIGN tumors , *CANCER relapse - Abstract
Backgrounds: It is not clear when and how frequently surveillance endoscopy should be performed after colorectal endoscopic submucosal dissection (ESD). We aimed to suggest a surveillance endoscopy strategy by investigating the cumulative local recurrence rates and identifying risk factors for local recurrence after colorectal ESD. Methods: We reviewed the medical records of 770 patients who underwent colorectal ESD for 778 lesions at our institution from 2005 to 2016. We investigated the cumulative local recurrence rates and risk factors for local recurrence. Results: Local recurrence developed in 12 (1.5%) of 778 lesions during the follow-up period of 37.4 ± 31.7 months. The one-, three-, and five-year cumulative local recurrence rates were 0.4%, 1.7%, and 2.2%, respectively. The risk factors for local recurrence were piecemeal resection (odds ratio (OR) 3.948, 95% confidence interval (CI) 1.164–13.385; p = 0.028) and histological incomplete resection (OR 8.713, 95% CI 2.588–29.334; p < 0.001). Local recurrence tended to develop frequently after ESD of early cancers. Conclusions: Short-term surveillance endoscopy should be recommended after piecemeal ESD, histological incomplete resection, and ESD of early colorectal cancers. Surveillance endoscopy with longer intervals can be suggested after en bloc ESD with the histological complete resection of benign colorectal tumors. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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79. The Distinct Properties of the Consecutive Disordered Regions Inside or Outside Protein Domains and Their Functional Significance.
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Wang, Huqiang, Zhong, Haolin, Gao, Chao, Zang, Jiayin, and Yang, Dong
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PROTEIN domains , *POST-translational modification - Abstract
The consecutive disordered regions (CDRs) are the basis for the formation of intrinsically disordered proteins, which contribute to various biological functions and increasing organism complexity. Previous studies have revealed that CDRs may be present inside or outside protein domains, but a comprehensive analysis of the property differences between these two types of CDRs and the proteins containing them is lacking. In this study, we investigated this issue from three viewpoints. Firstly, we found that in-domain CDRs are more hydrophilic and stable but have less stickiness and fewer post-translational modification sites compared with out-domain CDRs. Secondly, at the protein level, we found that proteins with only in-domain CDRs originated late, evolved rapidly, and had weak functional constraints, compared with the other two types of CDR-containing proteins. Proteins with only in-domain CDRs tend to be expressed spatiotemporal specifically, but they tend to have higher abundance and are more stable. Thirdly, we screened the CDR-containing protein domains that have a strong correlation with organism complexity. The CDR-containing domains tend to be evolutionarily young, or they changed from a domain without CDR to a CDR-containing domain during evolution. These results provide valuable new insights about the evolution and function of CDRs and protein domains. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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80. Factors Affecting Route Selection of Balloon-Assisted Enteroscopy in Patients with Obscure Gastrointestinal Bleeding: A KASID Multicenter Study.
- Author
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Baek, Dong Hoon, Hwang, Seonyeong, Eun, Chang Soo, Jeon, Seong Ran, Kim, Jinsu, Kim, Eun Ran, Yang, Dong-Hoon, Jang, Hyun Joo, Im, Jong Pil, Park, Soo Jung, and Jung, Sung Hoon
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GASTROINTESTINAL hemorrhage , *ENTEROSCOPY , *SMALL intestine , *CAPSULE endoscopy , *COMPUTED tomography - Abstract
Balloon-assisted enteroscopy (BAE) is an important diagnostic modality for ongoing obscure gastrointestinal bleeding (OGIB). However, it is difficult to determine the optimal insertion route. We retrospectively analyzed the records of patients with OGIB contained in a multicenter enteroscopy database of 1108 balloon-assisted enteroscopy (BAE) procedures (875 patients) to find out factors affecting BAE route selection in patients with OGIB. A total of 603 BAE procedures in 512 patients were investigated: there were 392 (65.0%) bidirectional and 211 (35.0%) unidirectional procedures. Overt OGIB was more frequent in the latter group (p = 0.024). Computed tomography (CT) was more frequently performed in the unidirectional group (p < 0.001). Capsule endoscopy and a small bowel barium study were performed more frequently in the bidirectional group (p < 0.001 and p = 0.039, respectively). Multivariate analysis showed that occult OGIB, capsule endoscopy and a small bowel barium study were independently associated with use of the bidirectional approach (p = 0.011, p = 0.013 and p = 0.046, respectively). Conversely, CT was associated with use of the unidirectional approach (p < 0.001). Conclusion: CT can aid the selection of an optimal insertion route in OGIB patients. However, capsule endoscopy and small bowel barium study are unhelpful. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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81. Photo-Switchable Aggregation-Induced Emission of Bisthienylethene-Dipyrimido[2,1- b ][1,3]benzothiazole Triad.
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Gong, Shan-Shan, Zheng, Chun-Hong, Chen, Zhen-Zhen, Yang, Dong-Zhao, Chi, Mei, Pu, Shou-Zhi, and Sun, Qi
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BENZOTHIAZOLE , *VISIBLE spectra - Abstract
A bisthienylethene-dipyrimido[2,1-b][1,3]benzothiazole (BTE-2PBT) triad has been designed and synthesized based on our recent discovery of PBTs as atypical propeller-shaped novel AIEgens. The triad not only maintains the photochromic properties of BTE moiety in solution, film, and solid state but also exhibits remarkable AIE properties. Moreover, the fluorescence of BTE-2PBT PMMA film could be modulated with high contrast by alternate UV and visible light irradiation. Photoerasing, rewriting, and non-destructive readout of fluorescent images on BTE-2PBT PMMA film well demonstrate its potential application as optical memory media. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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82. Validation of FY-3D MERSI-2 Precipitable Water Vapor (PWV) Datasets Using Ground-Based PWV Data from AERONET.
- Author
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Xie, Yanqing, Li, Zhengqiang, Hou, Weizhen, Guang, Jie, Ma, Yan, Wang, Yuyang, Wang, Siheng, and Yang, Dong
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PRECIPITABLE water , *STANDARD deviations , *METEOROLOGICAL satellites , *WATER vapor - Abstract
The medium resolution spectral imager-2 (MERSI-2) is one of the most important sensors onboard China's latest polar-orbiting meteorological satellite, Fengyun-3D (FY-3D). The National Satellite Meteorological Center of China Meteorological Administration has developed four precipitable water vapor (PWV) datasets using five near-infrared bands of MERSI-2, including the P905 dataset, P936 dataset, P940 dataset and the fusion dataset of the above three datasets. For the convenience of users, we comprehensively evaluate the quality of these PWV datasets with the ground-based PWV data derived from Aerosol Robotic Network. The validation results show that the P905, P936 and fused PWV datasets have relatively large systematic errors (−0.10, −0.11 and −0.07 g/cm2), whereas the systematic error of the P940 dataset (−0.02 g/cm2) is very small. According to the overall accuracy of these four PWV datasets by our assessments, they can be ranked in descending order as P940 dataset, fused dataset, P936 dataset and P905 dataset. The root mean square error (RMSE), relative error (RE) and percentage of retrieval results with error within ± (0.05 + 0.10 ∗ P W V A E R O N E T ) (PER10) of the P940 PWV dataset are 0.24 g/cm2, 0.10 and 76.36%, respectively. The RMSE, RE and PER10 of the P905 PWV dataset are 0.38 g/cm2, 0.15 and 57.72%, respectively. In order to obtain a clearer understanding of the accuracy of these four MERSI-2 PWV datasets, we compare the accuracy of these four MERSI-2 PWV datasets with that of the widely used MODIS PWV dataset and AIRS PWV dataset. The results of the comparison show that the accuracy of the MODIS PWV dataset is not as good as that of all four MERSI-2 PWV datasets, due to the serious overestimation of the MODIS PWV dataset (0.40 g/cm2), and the accuracy of the AIRS PWV dataset is worse than that of the P940 and fused MERSI-2 PWV datasets. In addition, we analyze the error distribution of the four PWV datasets in different locations, seasons and water vapor content. Finally, the reason why the fused PWV dataset is not the one with the highest accuracy among the four PWV datasets is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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83. Research Advances in Heterotrimeric G-Protein α Subunits and Uncanonical G-Protein Coupled Receptors in Plants.
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Liu, Ying, Wang, Xiaoyun, Dong, Danhui, Guo, Luqin, Dong, Xiaonan, Leng, Jing, Zhao, Bing, Guo, Yang-Dong, and Zhang, Na
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CELLULAR signal transduction , *G protein coupled receptors , *AGRICULTURAL productivity , *LABORATORY animals , *TRANSDUCERS - Abstract
As crucial signal transducers, G-proteins and G-protein-coupled receptors (GPCRs) have attracted increasing attention in the field of signal transduction. Research on G-proteins and GPCRs has mainly focused on animals, while research on plants is relatively rare. The mode of action of G-proteins is quite different from that in animals. The G-protein α (Gα) subunit is the most essential member of the G-protein signal cycle in animals and plants. The G-protein is activated when Gα releases GDP and binds to GTP, and the relationships with the GPCR and the downstream signal are also achieved by Gα coupling. It is important to study the role of Gα in the signaling pathway to explore the regulatory mechanism of G-proteins. The existence of a self-activated Gα in plants makes it unnecessary for the canonical GPCR to activate the G-protein by exchanging GDP with GTP. However, putative GPCRs have been found and proven to play important roles in G-protein signal transduction. The unique mode of action of G-proteins and the function of putative GPCRs in plants suggest that the same definition used in animal research cannot be used to study uncanonical GPCRs in plants. This review focuses on the different functions of the Gα and the mode of action between plants and animals as well as the functions of the uncanonical GPCR. This review employs a new perspective to define uncanonical GPCRs in plants and emphasizes the role of uncanonical GPCRs and Gα subunits in plant stress resistance and agricultural production. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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84. Identification of Potentially Related Genes and Mechanisms Involved in Skeletal Muscle Atrophy Induced by Excessive Exercise in Zebrafish.
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Sun, Chen-Chen, Zhou, Zuo-Qiong, Chen, Zhang-Lin, Zhu, Run-Kang, Yang, Dong, Peng, Xi-Yang, Zheng, Lan, and Tang, Chang-Fa
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MUSCULAR atrophy , *SKELETAL muscle , *AEROBIC capacity , *OXYGEN consumption , *MUSCLE weakness , *GENE regulatory networks , *BRACHYDANIO , *FISH locomotion - Abstract
Simple Summary: Excessive exercise can lead to muscle atrophy, which is particularly concerning in professional athletes. However, the effects of excessive exercise on the skeletal muscle system remain unclear. Here, we used a zebrafish model of excessive exercise to identify genes that are dysregulated during excessive exercise. We mapped the identified genes to regulatory networks to gain an understanding of their functions during muscle atrophy. We identified several important mechanisms by which excessive exercise can lead to muscle wasting and prevent regeneration. Our findings provide fundamental knowledge on the effect of overtraining on the skeletal muscle system, and will enable better monitoring of muscle condition in athletes. Long-term imbalance between fatigue and recovery may eventually lead to muscle weakness or even atrophy. We previously reported that excessive exercise induces pathological cardiac hypertrophy. However, the effect of excessive exercise on the skeletal muscles remains unclear. In the present study, we successfully established an excessive-exercise-induced skeletal muscle atrophy zebrafish model, with decreased muscle fiber size, critical swimming speed, and maximal oxygen consumption. High-throughput RNA-seq analysis identified differentially expressed genes in the model system compared with control zebrafish. Gene ontology and KEGG enrichment analysis revealed that the upregulated genes were enriched in autophagy, homeostasis, circadian rhythm, response to oxidative stress, apoptosis, the p53 signaling pathway, and the FoxO signaling pathway. Protein–protein interaction network analysis identified several hub genes, including keap1b, per3, ulk1b, socs2, esrp1, bcl2l1, hsp70, igf2r, mdm2, rab18a, col1a1a, fn1a, ppih, tpx2, uba5, nhlrc2, mcm4, tac1, b3gat3, and ddost, that correlate with the pathogenesis of skeletal muscle atrophy induced by excessive exercise. The underlying regulatory pathways and muscle-pressure-response-related genes identified in the present study will provide valuable insights for prescribing safe and accurate exercise programs for athletes and the supervision and clinical treatment of muscle atrophy induced by excessive exercise. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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85. Prognostic Value of Computed Tomographic Coronary Angiography for Long-Term Major Adverse Cardiac Events after Liver Transplantation.
- Author
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Kim, Doo-Hwan, Kim, Young-Kug, Ha, Tae-Yong, Hwang, Shin, Kim, Wooil, Koo, Hyun-Jung, Yang, Dong-Hyun, Kang, Joon-Won, and Lee, Sung-Gyu
- Subjects
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CORONARY angiography , *PROGNOSIS , *LIVER transplantation , *CORONARY artery disease , *CORONARY artery stenosis , *MAJOR adverse cardiovascular events - Abstract
Computed tomographic coronary angiography (CTCA) has prognostic value for early major adverse cardiac events (MACEs) after liver transplantation. However, the association between CTCA and long-term MACEs in liver transplant (LT) recipients remains unknown. We evaluated the association between CTCA and long-term MACEs within 5 years after living donor liver transplantation (LDLT). A total of 628 LDLT recipients who underwent CTCA were analyzed between 2010 and 2012. MACEs were investigated within 5 years after LDLT. The factors associated with long-term MACEs in transplant recipients were evaluated. Only 48 (7.6%) patients developed MACEs. In the Fine and Gray competing risk regression, a coronary artery calcium score (CACS) of >400 combined with obstructive coronary artery disease (CAD) (subdistribution hazard ratio: 5.01, 95% confidence interval: 2.37–10.58, p < 0.001), age (1.05, 1.01–1.10, p = 0.018), diabetes mellitus (2.43, 1.37–4.29, p = 0.002), dyslipidemia (2.45, 1.23–4.70, p = 0.023), and creatinine (1.19, 1.08–1.30, p < 0.001) were independently associated with long-term MACEs. CACS (>400) combined with obstructive CAD may be associated with MACEs within 5 years after LDLT, suggesting the importance of preoperative noninvasive CTCA in LT recipients. The evaluation of coronary artery stenosis on CTCA combined with CACS may have a prognostic value for long-term MACEs in LT recipients. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
86. Monitoring the Spatiotemporal Dynamics of Aeolian Desertification Using Google Earth Engine.
- Author
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Chen, Ang, Yang, Xiuchun, Xu, Bin, Jin, Yunxiang, Guo, Jian, Xing, Xiaoyu, Yang, Dong, Wang, Ping, Zhu, Libo, and Wang, Guangxing
- Subjects
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DESERTIFICATION , *EOLIAN processes , *DRONE aircraft , *REMOTE sensing - Abstract
Northern China has been long threatened by aeolian desertification. In recent years, all levels of the Chinese government have performed a series of ecological protection and sand control projects. To grasp the implementation effects of these projects and adjust policies in time, it is necessary to understand the process of aeolian desertification quickly and accurately. Remote sensing technologies play an irreplaceable role in aeolian desertification monitoring. In this study, the Zhenglan Banner, which is in the hinterland of the Hunshandake Sandy Land, was considered as the research area. Based on unmanned aerial vehicle (UAV) images, ground survey data, and Landsat images called in Google Earth Engine (GEE), the aeolian desertified land (ADL) in 2000, 2004, 2010, 2015, and 2019 was extracted using spectral mixture analysis. A desertification index (DI) was constructed to evaluate the spatial and temporal dynamics of the ADL in the Zhenglan Banner. Finally, a residual analysis explored the driving forces of aeolian desertification. The results showed that (1) the ADL area in the Zhenglan Banner has been trending downwards over the past 20 years but rebounded from 2004 to 2010; (2) over the past 20 years, the area of slightly, moderately, and severely desertified land has decreased at annual rates of 0.4%, 2.7%, and 3.4%, respectively; (3) human activities had significantly positive and negative impacts on the aeolian desertification trend for 20.0% and 21.0% of the study area, respectively, but not for the rest. This paper explored new techniques for rapid aeolian desertification monitoring and is of great significance for controlling and managing aeolian desertification in this region. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
87. Examining Relationships between Heat Requirement of Remotely Sensed Green-Up Date and Meteorological Indicators in the Hulun Buir Grassland.
- Author
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Guo, Jian, Yang, Xiuchun, Chen, Fan, Niu, Jianming, Luo, Sha, Zhang, Min, Jin, Yunxiang, Shen, Ge, Chen, Ang, Xing, Xiaoyu, Yang, Dong, Xu, Bin, and Bajocco, Sofia
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PLANT phenology , *GRASSLANDS , *CLIMATE change , *TECHNICAL specifications , *STANDARD deviations , *SOLAR radiation - Abstract
The accumulation of heat and moderate precipitation are the primary factors that are used by grasslands to trigger a green-up date. The accumulated growing degree-days (AGDD) requirement over the preseason is an important indicator of the response of grassland spring phenology to climate change. This study adopted the Normalized Difference Phenology Index (NDPI), which derived from the Moderate Resolution Imaging Spectroradiometer (MODIS), to extract annual green-up dates in the Hulun Buir grassland in China between 2001–2015. Our analysis indicated that the range (standard deviation) and trend for the green-up date were DOY (day of year) 104 to DOY 144 (10.6 days) and −2.0 days per decade. Nine point two percent of the study area had significant (p < 0.05) changes in AGDD requirements. The partial correlations between the AGDD requirements and chilling days (67.04%, pixels proportion) were negative and significant (p < 0.05). The partial correlations between the AGDD requirement and precipitation (28.87%) were positive and significant (p < 0.05). Finally, the partial correlation between the AGDD requirement and insolation (97.65%) were positive and significant (p < 0.05). The results of this study could reveal the response of vegetation to climate warming and contribute to improving the phenological mechanism model of different grassland types in future research. [ABSTRACT FROM AUTHOR]
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- 2021
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88. Cyanidin 3- O -galactoside: A Natural Compound with Multiple Health Benefits.
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Liang, Zhongxin, Liang, Hongrui, Guo, Yizhan, Yang, Dong, and Truzzi, Francesca
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CYANIDIN , *BERRIES , *CHEMICAL stability , *FOOD additives , *URIDINE diphosphate , *APPLES , *ANIMAL health - Abstract
Cyanidin 3-O-galactoside (Cy3Gal) is one of the most widespread anthocyanins that positively impacts the health of animals and humans. Since it is available from a wide range of natural sources, such as fruits (apples and berries in particular), substantial studies were performed to investigate its biosynthesis, chemical stability, natural occurrences and content, extraction methods, physiological functions, as well as potential applications. In this review, we focus on presenting the previous studies on the abovementioned aspects of Cy3Gal. As a conclusion, Cy3Gal shares a common biosynthesis pathway and analogous stability with other anthocyanins. Galactosyltransferase utilizing uridine diphosphate galactose (UDP-galactose) and cyanidin as substrates is unique for Cy3Gal biosynthesis. Extraction employing different methods reveals chokeberry as the most practical natural source for mass-production of this compound. The antioxidant properties and other health effects, including anti-inflammatory, anticancer, antidiabetic, anti-toxicity, cardiovascular, and nervous protective capacities, are highlighted in purified Cy3Gal and in its combination with other polyphenols. These unique properties of Cy3Gal are discussed and compared with other anthocyanins with related structure for an in-depth evaluation of its potential value as food additives or health supplement. Emphasis is laid on the description of its physiological functions confirmed via various approaches. [ABSTRACT FROM AUTHOR]
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- 2021
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89. Hexane Extract of Chloranthus japonicus Increases Adipocyte Differentiation by Acting on Wnt/β-Catenin Signaling Pathway.
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Yun, Ui Jeong, Nho, Chu Won, Park, Kye Won, Yang, Dong Kwon, Capasso, Raffaele, Saleh-E-In, Md. Moshfekus, and Adnan, Md.
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ADIPOGENESIS , *PEROXISOME proliferator-activated receptors , *HEXANE , *WNT proteins , *METABOLIC syndrome , *NATURAL products - Abstract
Chloranthus japonicus has been heavily investigated for the treatment of various diseases. This paper attempts to show that Chloranthus japonicus can modulate adipocyte differentiation of preadipocytes. To establish this, we investigated the effects of Chloranthus japonicus extract in peroxisome proliferator-activated receptor γ (PPARγ) expression, adipogenesis, and the underlying molecular mechanisms in C3H10T1/2 and 3T3-L1 cells. Our data showed that Chloranthus japonicus methanol extract increased lipid accumulation and promoted adipocyte differentiation. Further studies on the fractionation with various solvents led to the identification of Chloranthus japonicus hexane extract (CJHE) as the most potent inducer of adipocyte differentiation. CJHE consistently increased lipid accumulation and adipocyte marker expression including Pparγ and it acted during the early stages of adipocyte differentiation. Mechanistic studies revealed that CJHE and a Wnt inhibitor similarly stimulated adipogenesis and were active in Wnt-selective reporter assays. The effects of CJHE were inhibited by Wnt3a protein treatment and were significantly blunted in β-catenin-silenced cells, further suggesting that CJHE acted on Wnt pathways to promote adipogenesis. We also showed that Chloranthus japonicus extracts generated from different plant parts similarly promoted adipocyte differentiation. These results identified Chloranthus japonicus as a pro-adipogenic natural product and suggest its potential use in metabolic syndrome. [ABSTRACT FROM AUTHOR]
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- 2021
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90. p -Coumaric Acid Enhances Hypothalamic Leptin Signaling and Glucose Homeostasis in Mice via Differential Effects on AMPK Activation.
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Nguyen, Linh V., Nguyen, Khoa D. A., Ma, Chi-Thanh, Nguyen, Quoc-Thai, Nguyen, Huong T. H., Yang, Dong-Joo, Tran, Trung Le, Kim, Ki Woo, Doan, Khanh V., and Luca, Antonio De
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INSULIN sensitivity , *HOMEOSTASIS , *GLUCOSE , *BLOOD sugar , *HYDROXYCINNAMIC acids - Abstract
AMP-activated protein kinase (AMPK) plays a crucial role in the regulation of energy homeostasis in both peripheral metabolic organs and the central nervous system. Recent studies indicated that p-Coumaric acid (CA), a hydroxycinnamic phenolic acid, potentially activated the peripheral AMPK pathway to exert beneficial effects on glucose metabolism in vitro. However, CA's actions on central AMPK activity and whole-body glucose homeostasis have not yet been investigated. Here, we reported that CA exhibited different effects on peripheral and central AMPK activation both in vitro and in vivo. Specifically, while CA treatment promoted hepatic AMPK activation, it showed an inhibitory effect on hypothalamic AMPK activity possibly by activating the S6 kinase. Furthermore, CA treatment enhanced hypothalamic leptin sensitivity, resulting in increased proopiomelanocortin (POMC) expression, decreased agouti-related peptide (AgRP) expression, and reduced daily food intake. Overall, CA treatment improved blood glucose control, glucose tolerance, and insulin sensitivity. Together, these results suggested that CA treatment enhanced hypothalamic leptin signaling and whole-body glucose homeostasis, possibly via its differential effects on AMPK activation. [ABSTRACT FROM AUTHOR]
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- 2021
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91. Triglyceride Glucose-Waist Circumference Better Predicts Coronary Calcium Progression Compared with Other Indices of Insulin Resistance: A Longitudinal Observational Study.
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Cho, Yun Kyung, Lee, Jiwoo, Kim, Hwi Seung, Kim, Eun Hee, Lee, Min Jung, Yang, Dong Hyun, Kang, Joon-Won, Jung, Chang Hee, Park, Joong-Yeol, Kim, Hong-Kyu, and Lee, Woo Je
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INSULIN resistance , *LONGITUDINAL method , *SCIENTIFIC observation , *BODY mass index , *TRIGLYCERIDES - Abstract
The triglyceride glucose (TyG) index, a product of triglyceride and fasting glucose, is a reliable marker for insulin resistance. We aimed to investigate the association between the TyG-related markers and coronary artery calcification (CAC) progression. We enrolled 1145 asymptomatic participants who underwent repeated CAC score measurements during routine health examinations. Homeostasis model assessment of insulin resistance (HOMA-IR), TyG index, TyG-BMI (body mass index), and TyG-WC (waist circumference) were calculated. Progression of CAC was defined as (1) incident CAC in a CAC-free population, or an (2) increase of ≥2.5 units between the baseline and final square root of the CAC scores in participants with detectable CAC. According to the quartiles of parameters, we stratified the subjects into four groups. The prevalence of progression increased with the TyG-WC quartile (15.0%, 24.1%, 31.0%, and 32.2% for each of the groups; p < 0.001). The multivariate-adjusted odds ratio (95% confidence interval) for CAC score progression was 1.66 (1.01–2.77) when the highest and lowest TyG-WC index quartiles were compared. Furthermore, the predictability of TyG-WC for CAC progression was better than the other indices in terms of the area under the curve. The TyG-WC index predicted CAC progression better than other indices and could be a potential marker of future coronary atherosclerosis. [ABSTRACT FROM AUTHOR]
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- 2021
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92. High-Molecular-Weight Glutenin Subunits: Genetics, Structures, and Relation to End Use Qualities.
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Li, Yi, Fu, Jiahui, Shen, Qun, and Yang, Dong
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GENETICS , *ALLELES , *GLUTEN , *HYDROGEN bonding , *CHROMOSOMES , *WHEAT diseases & pests - Abstract
High-molecular-weight glutenin subunits (HMW-GSs) are storage proteins present in the starchy endosperm cells of wheat grain. Encoding the synthesis of HMW-GS, the Glu-1 loci located on the long arms of group 1 chromosomes of the hexaploid wheat (1A, 1B, and 1D) present multiple allelism. In hexaploid wheat cultivars, almost all of them express 3 to 5 HMW-GSs and the 1Ay gene is always silent. Though HMW-GSs are the minor components in gluten, they are crucial for dough properties, and certain HMW-GSs make more positive contributions than others. The HMW-GS acts as a "chain extender" and provides a disulfide-bonded backbone in gluten network. Hydrogen bonds mediated by glutamine side chains are also crucial for stabilizing the gluten structure. In most cases, HMW-GSs with additional or less cysteines are related to the formation of relatively more or less interchain disulfide bonds and HMW-GSs also affect the gluten secondary structures, which in turn impact the end use qualities of dough. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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93. PDI-Regulated Disulfide Bond Formation in Protein Folding and Biomolecular Assembly.
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Fu, Jiahui, Gao, Jihui, Liang, Zhongxin, Yang, Dong, and Iwaoka, Michio
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PROTEIN folding , *PROTEIN disulfide isomerase , *PROTEIN structure , *WHEAT proteins , *LEAD toxicology , *ENDOPLASMIC reticulum - Abstract
Disulfide bonds play a pivotal role in maintaining the natural structures of proteins to ensure their performance of normal biological functions. Moreover, biological molecular assembly, such as the gluten network, is also largely dependent on the intermolecular crosslinking via disulfide bonds. In eukaryotes, the formation and rearrangement of most intra- and intermolecular disulfide bonds in the endoplasmic reticulum (ER) are mediated by protein disulfide isomerases (PDIs), which consist of multiple thioredoxin-like domains. These domains assist correct folding of proteins, as well as effectively prevent the aggregation of misfolded ones. Protein misfolding often leads to the formation of pathological protein aggregations that cause many diseases. On the other hand, glutenin aggregation and subsequent crosslinking are required for the formation of a rheologically dominating gluten network. Herein, the mechanism of PDI-regulated disulfide bond formation is important for understanding not only protein folding and associated diseases, but also the formation of functional biomolecular assembly. This review systematically illustrated the process of human protein disulfide isomerase (hPDI) mediated disulfide bond formation and complemented this with the current mechanism of wheat protein disulfide isomerase (wPDI) catalyzed formation of gluten networks. [ABSTRACT FROM AUTHOR]
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- 2021
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94. Poziotinib Inhibits the Efflux Activity of the ABCB1 and ABCG2 Transporters and the Expression of the ABCG2 Transporter Protein in Multidrug Resistant Colon Cancer Cells.
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Zhang, Yongchao, Wu, Zhuo-Xun, Yang, Yuqi, Wang, Jing-Quan, Li, Jun, Sun, Zoey, Teng, Qiu-Xu, Ashby Jr., Charles R., and Yang, Dong-Hua
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ADENOSINE triphosphatase , *ANTINEOPLASTIC agents , *CARRIER proteins , *CELL lines , *COLON tumors , *DOXORUBICIN , *DRUG resistance in cancer cells , *DOSE-effect relationship in pharmacology , *EPIDERMAL growth factor , *PACLITAXEL , *WESTERN immunoblotting , *PROTEIN-tyrosine kinase inhibitors , *MOLECULAR dynamics , *DESCRIPTIVE statistics , *MITOXANTRONE , *IN vitro studies , *MOLECULAR docking , *MEMBRANE transport proteins , *CHEMICAL inhibitors , *PHARMACODYNAMICS - Abstract
Simple Summary: Globally, colorectal cancer (CRC) is a leading cause of cancer deaths and chemotherapy, in combination with radiotherapy when appropriate, is used to treat the majority of CRC patients. However, the acquisition or development of drug resistance can decrease, or even abolish, the efficacy of chemotherapy. ATP-binding cassette (ABC) transporters, particularly, the ABCB1 and ABCG2 transporter, are mediators of multidrug resistance (MDR) in certain types of cancer cells. The aim of our in vitro study was to determine if poziotinib can overcome MDR to certain chemotherapeutic drugs in colon cancer cells. Our results indicated that in MDR CRC cell lines, poziotinib inhibits the transport function of the ABCB1 and ABCG2 transporters, increasing the intracellular accumulation of certain anticancer drugs, and thus, their efficacy. Furthermore, poziotinib decreased the expression of the ABCG2 protein. Therefore, if our results can be translated to humans, they suggest that using poziotinib in combination with certain anticancer drugs may be of therapeutic benefit in colorectal cancer patients. Colorectal cancer (CRC) is a leading cause of cancer deaths in the United States. Currently, chemotherapy is a first-line treatment for CRC. However, one major drawback of chemotherapy is the emergence of multidrug resistance (MDR). It has been well-established that the overexpression of the ABCB1 and/or ABCG2 transporters can produce MDR in cancer cells. In this study, we report that in vitro, poziotinib can antagonize both ABCB1- and ABCG2-mediated MDR at 0.1–0.6 μM in the human colon cancer cell lines, SW620/Ad300 and S1-M1-80. Mechanistic studies indicated that poziotinib increases the intracellular accumulation of the ABCB1 transporter substrates, paclitaxel and doxorubicin, and the ABCG2 transporter substrates, mitoxantrone and SN-38, by inhibiting their substrate efflux function. Accumulation assay results suggested that poziotinib binds reversibly to the ABCG2 and ABCB1 transporter. Furthermore, western blot experiments indicated that poziotinib, at 0.6 μM, significantly downregulates the expression of the ABCG2 but not the ABCB1 transporter protein, suggesting that the ABCG2 reversal effect produced by poziotinib is due to transporter downregulation and inhibition of substrate efflux. Poziotinib concentration-dependently stimulated the ATPase activity of both ABCB1 and ABCG2, with EC50 values of 0.02 μM and 0.21 μM, respectively, suggesting that it interacts with the drug-substrate binding site. Molecular docking analysis indicated that poziotinib binds to the ABCB1 (−6.6 kcal/mol) and ABCG2 (−10.1 kcal/mol) drug-substrate binding site. In summary, our novel results show that poziotinib interacts with the ABCB1 and ABCG2 transporter, suggesting that poziotinib may increase the efficacy of certain chemotherapeutic drugs used in treating MDR CRC. [ABSTRACT FROM AUTHOR]
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- 2020
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95. Exploration of Indoor Barrier-Free Plane Intelligent Lofting System Combining BIM and Multi-Sensors.
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Zhang, Zijian, Cheng, Xiaojun, Yang, Bilian, and Yang, Dong
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AUTONOMOUS robots , *MOBILE robots , *BUILDING information modeling , *TELECOMMUNICATION , *REMOTE sensing , *BEACONS , *ROBOTICS - Abstract
Lofting is an essential part of construction projects and the high quality of lofting is the basis of efficient construction. However, the most common method of lofting currently which uses the total station in a multi-person cooperative way consumes much manpower and time. With the rapid development of remote sensing and robot technology, using robots instead of manpower can effectively solve this problem, but few scholars study this. How to effectively combine remote sensing and robots with lofting is a challenging problem. In this paper, we propose an intelligent lofting system for indoor barrier-free plane environment, and design a high-flexibility, low-cost autonomous mobile robot platform based on single chip microcomputer, Micro Electro Mechanical Systems-Inertial Measurement Unit (MEMS-IMU), wheel encoder, and magnetometer. The robot also combines Building Information Modeling (BIM) laser lofting instrument and WIFI communication technology to get its own position. To ensure the accuracy of localization, the kinematics model of Mecanum wheel robot is built, and Extended Kalman Filter (EKF) is also used to fuse multi-sensor data. It can be seen from the final experimental results that this system can significantly improve lofting efficiency and reduce manpower. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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96. The wPDI Redox Cycle Coupled Conformational Change of the Repetitive Domain of the HMW-GS 1Dx5—A Computational Study.
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Gao, Jihui, Yu, Peixuan, Liang, Hongrui, Fu, Jiahui, Luo, Ziyue, Yang, Dong, Ruiz, Daniel Franco, López-Pedrouso, María, and Lorenzo, Jose Manuel
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PROTEIN disulfide isomerase , *OXIDATION-reduction reaction , *WHEAT proteins , *MOLECULAR interactions , *MOLECULAR weights - Abstract
The repetitive sequence of glutenin plays an important role in dough rheology; however, its interaction with wheat protein disulfide isomerase (wPDI) remains unclear. In this study, the conformations of wild type glutenin repetitive sequence (WRS) from the high molecular weight glutenin subunit (HMW-GS) 1Dx5, an artificially designed glutenin repetitive sequence (DRS) of which the amino acid composition is the same but the primary structure is different, and wPDI under different redox states were simulated. The molecular interactions between the aforementioned repetitive sequences with wPDI under different redox states were further investigated. The results indicated that the repetitive sequences bind to the b and b′ domains of an "open", oxidized wPDI (wPDIO) which serves as the acceptor state of substrate. The repetitive sequence is partially folded (compressed) in wPDIO, and is further folded in the thermodynamically favored, subsequent conformational transition of wPDIO to reduced wPDI (wPDIR). Compared with the artificially designed one, the naturally designed repetitive sequence is better recognized and more intensively folded by wPDI for its later unfold as the molecular basis of dough extension. [ABSTRACT FROM AUTHOR]
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- 2020
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97. Diversity of Ginsenoside Profiles Produced by Various Processing Technologies.
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Piao, Xiang Min, Huo, Yue, Kang, Jong Pyo, Mathiyalagan, Ramya, Zhang, Hao, Yang, Dong Uk, Kim, Mia, Yang, Deok Chun, Kang, Se Chan, Wang, Ying Ping, and Verotta, Luisella
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DIETARY supplements , *GINSENOSIDES , *ADDITION reactions , *MOIETIES (Chemistry) , *GINSENG , *HERBAL medicine , *BIOCONVERSION - Abstract
Ginseng is a traditional medicinal herb commonly consumed world-wide owing to its unique family of saponins called ginsenosides. The absorption and bioavailability of ginsenosides mainly depend on an individual's gastrointestinal bioconversion abilities. There is a need to improve ginseng processing to predictably increase the pharmacologically active of ginsenosides. Various types of ginseng, such as fresh, white, steamed, acid-processed, and fermented ginsengs, are available. The various ginseng processing methods produce a range ginsenoside compositions with diverse pharmacological properties. This review is intended to summarize the properties of the ginsenosides found in different Panax species as well as the different processing methods. The sugar moiety attached to the C–3, C–6, or C–20 deglycosylated to produce minor ginsenosides, such as Rb1, Rb2, Rc, Rd→Rg3, F2, Rh2; Re, Rf→Rg1, Rg2, F1, Rh1. The malonyl-Rb1, Rb2, Rc, and Rd were demalonylated into ginsenoside Rb1, Rb2, Rc, and Rd by dehydration. Dehydration also produces minor ginsenosides such as Rg3→Rk1, Rg5, Rz1; Rh2→Rk2, Rh3; Rh1→Rh4, Rk3; Rg2→Rg6, F4; Rs3→Rs4, Rs5; Rf→Rg9, Rg10. Acetylation of several ginsenosides may generate acetylated ginsenosides Rg5, Rk1, Rh4, Rk3, Rs4, Rs5, Rs6, and Rs7. Acid processing methods produces Rh1→Rk3, Rh4; Rh2→Rk1, Rg5; Rg3→Rk2, Rh3; Re, Rf, Rg2→F1, Rh1, Rf2, Rf3, Rg6, F4, Rg9. Alkaline produces Rh16, Rh3, Rh1, F4, Rk1, ginsenoslaloside-I, 20(S)-ginsenoside-Rh1-60-acetate, 20(R)-ginsenoside Rh19, zingibroside-R1 through hydrolysis, hydration addition reactions, and dehydration. Moreover, biological processing of ginseng generates the minor ginsenosides of Rg3, F2, Rh2, CK, Rh1, Mc, compound O, compound Y through hydrolysis reactions, and synthetic ginsenosides Rd12 and Ia are produced through glycosylation. This review with respect to the properties of particular ginsenosides could serve to increase the utilization of ginseng in agricultural products, food, dietary supplements, health supplements, and medicines, and may also spur future development of novel highly functional ginseng products through a combination of various processing methods. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
98. Evaluation of the Pharmacokinetic Drug–Drug Interaction between Micronized Fenofibrate and Pitavastatin in Healthy Volunteers.
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Lee, Hae Won, Kang, Woo Youl, Jung, Wookjae, Gwon, Mi-Ri, Cho, Kyunghee, Yang, Dong Heon, Yoon, Young-Ran, and Seong, Sook Jin
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TANDEM mass spectrometry , *FENOFIBRATE , *PHARMACOKINETICS , *HIGH performance liquid chromatography - Abstract
Dyslipidemia is a major risk factor for development of atherosclerosis and cardiovascular disease (CVD). Effective lipid-lowering therapies has led to CVD risk reduction. This study evaluated the possible pharmacokinetic interactions between fenofibrate, a peroxisome proliferators-activated receptors α agonist, and pitavastatin, a 3-hydoxy-3-methylglutaryl-coenzyme A reductase inhibitor, in healthy Korean subjects. The study design was an open-label, randomized, multiple-dose, three-period, and six-sequence crossover study with a 10-day washout in 24 healthy volunteers. It had three treatments: 160 mg of micronized fenofibrate once daily for 5 days; 2 mg of pitavastatin once daily for 5 days; and 160 mg of micronized fenofibrate with 2 mg of pitavastatin for 5 days. Serial blood samples were collected at scheduled intervals for up to 48 h after the last dose in each period to determine the steady-state pharmacokinetics of both drugs. Plasma concentrations of fenofibric acid and pitavastatin were measured using a validated high-performance liquid chromatography with the tandem mass spectrometry method. A total of 24 subjects completed the study. Pitavastatin, when co-administered with micronized fenofibrate, had no effect on the Cmax,ss and AUCτ,ss of fenofibric acid. The Cmax,ss and AUCτ,ss of pitavastatin were increased by 36% and 12%, respectively, when co-administered with fenofibrate. Combined treatment with pitavastatin and micronized fenofibrate was generally well tolerated without serious adverse events. Our results demonstrated no clinically significant pharmacokinetic interactions between micronized fenofibrate and pitavastatin when 160 mg of micronized fenofibrate and 2 mg of pitavastatin are co-administered. The treatments were well tolerated during the study, with no serious adverse events. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
99. Advances in Saponin Diversity of Panax ginseng.
- Author
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Piao, Xiangmin, Zhang, Hao, Kang, Jong Pyo, Yang, Dong Uk, Li, Yali, Pang, Shifeng, Jin, Yinping, Yang, Deok Chun, Wang, Yingping, and Verotta, Luisella
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GINSENG , *GINSENOSIDES , *CHEMICAL formulas , *CHEMICAL structure , *ISOMERS , *ROOTSTOCKS , *PLANT nutrition - Abstract
Ginsenosides are the major bioactive constituents of Panax ginseng, which have pharmacological effects. Although there are several reviews in regards to ginsenosides, new ginsenosides have been detected continually in recent years. This review updates the ginsenoside list from P. ginseng to 170 by the end of 2019, and aims to highlight the diversity of ginsenosides in multiple dimensions, including chemical structure, tissue spatial distribution, time, and isomeride. Protopanaxadiol, protopanaxatriol and C17 side-chain varied (C17SCV) manners are the major types of ginsenosides, and the constitute of ginsenosides varied significantly among different parts. Only 16 ginsenosides commonly exist in all parts of a ginseng plant. Protopanaxadiol-type ginsenoside is dominant in root, rhizome, leaf, stem, and fruit, whereas malonyl- and C17SCV-type ginsenosides occupy a greater proportion in the flower and flower bud compared with other parts. In respects of isomeride, there are 69 molecular formulas corresponding to 170 ginsenosides, and the median of isomers is 2. This is the first review on diversity of ginsenosides, providing information for reasonable utilization of whole ginseng plant, and the perspective on studying the physiological functions of ginsenoside for the ginseng plant itself is also proposed. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
100. The Multidrug Resistance-Reversing Activity of a Novel Antimicrobial Peptide.
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Teng, Qiu-Xu, Luo, Xiaofang, Lei, Zi-Ning, Wang, Jing-Quan, Wurpel, John, Qin, Zuodong, and Yang, Dong-Hua
- Subjects
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COMBINATION drug therapy , *DOXORUBICIN , *ANTI-infective agents , *GENE expression , *GLYCOPROTEINS , *TUMORS , *PACLITAXEL , *CELL lines , *DRUG resistance in cancer cells , *CARRIER proteins , *PHARMACODYNAMICS - Abstract
The overexpression of ATP-binding cassette (ABC) transporters is a common cause of multidrug resistance (MDR) in cancers. The intracellular drug concentration of cancer cells can be decreased relative to their normal cell counterparts due to increased expression of ABC transporters acting as efflux pumps of anticancer drugs. Over the past decades, antimicrobial peptides have been investigated as a new generation of anticancer drugs and some of them were reported to have interactions with ABC transporters. In this article, we investigated several novel antimicrobial peptides to see if they could sensitize ABCB1-overexpressing cells to the anticancer drugs paclitaxel and doxorubicin, which are transported by ABCB1. It was found that peptide XH-14C increased the intracellular accumulation of ABCB1 substrate paclitaxel, which demonstrated that XH-14C could reverse ABCB1-mediated MDR. Furthermore, XH-14C could stimulate the ATPase activity of ABCB1 and the molecular dynamic simulation revealed a stable binding pose of XH-14C-ABCB1 complex. There was no change on the expression level or the location of ABCB1 transporter with the treatment of XH-14C. Our results suggest that XH-14C in combination with conventional anticancer agents could be used as a novel strategy for cancer treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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