Rocaglamide-A Potentiates Osteoblast Differentiation by Inhibiting NF-κB Signaling

Aiguo Li,Libin Yang,Xiaolin Geng,Xingmei Peng,Tan Lu,Yanjun Deng,Yuzheng Dong 한국분자세포생물학회 2015 Molecules and cells Vol.38 No.11

Rheumatoid arthritis is a chronic inflammatory disease that leads to bone and cartilage erosion. The inhibition of osteoblast differentiation by the inflammatory factor TNF-α is critical for the pathogenesis of rheumatoid arthritis. To modulate TNF-α mediated inhibition of osteoblast differentiation is required to improve therapeutic efficacy of rheumatoid arthritis. Here, we explored the potential role of rocaglamide-A, a component of Aglaia plant, in osteoblast differentiation. Rocaglamide-A prevented TNF-α mediated inhibition of osteoblast differentiation,and promoted osteoblast differentiation directly,in both C2C12 and primary mesenchymal stromal cells. Mechanistically, Rocaglamide- A inhibited the phosphorylation of NF-κB component p65 protein and the accumulation of p65 in nucleus, which resulted in the diminished NF-κB responsible transcriptional activity. Oppositely, overexpression of p65 reversed rocaglamide-A’s protective effects on osteoblast differentiation. Collectively, rocaglamide-A protected and stimulated osteoblast differentiation via blocking NF-κB pathway. It suggests that rocaglamide-A may be a good candidate to develop as therapeutic drug for rheumatoid arthritis associated bone loss diseases.

A Cut‑Out Strategy for Wind Turbines that Ensures Low‑Voltage Ride‑Through Capability

Aiguo Tan,Zhihan Tang,Xianbo Sun,Jianwei Zhong,Honghua Liao,Haibing Fang 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

To ensure the dynamic stability of the system and improve low-voltage ride-through (LVRT) capability, this study presents a cut-out strategy for doubly-fed induction generator (DFIG) wind turbines that combines reactive power output with asynchronous load reduction. This strategy reduces the risk of the large-scale disconnection of DFIGs in a wind farm by regulating the reactive power output of DFIGs in the wind farm and removing DFIGs in an asynchronous state based on the reduction ratio. Simulation results demonstrate that the implementation of this strategy can help increase the voltage at the point of common coupling and the LVRT time for a wind farm.

BIOMEDICAL APPLICATIONS OF MAGNETIC NANOPARTICLES

AIGUO WU,PING OU,LEYONG ZENG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2010 NANO Vol.5 No.5

In this review, the applications of magnetic nanoparticles in biomedicine are summarized and introduced in three parts. (1) A short description of magnetic nanoparticles is explained. (2) Applications of magnetic nanoparticles in biomedicine are summarized. In biology, new progress of the magnetic separation techniques based on magnetic nanoparticles is discussed. In medicine, the magnetic nanoparticles as therapeutic agents (particularly as a hyperthermia agent, a targeted drug delivery carrier, and a magnetofection agent) as well as contrast agents in magnetic resonance imaging (MRI) are explained in detail. (3) A discussion and remarking conclusion of magnetic nanoparticles in biomedical applications are described. Finally, a perspective of the magnetic nanoparticles in biomedicine in future is also described.

TITANIUM DIOXIDE NANOPARTICLES ASSEMBLED BY DNA MOLECULES HYBRIDIZATION AND LOADING OF DNA INTERACTING PROTEINS

AIGUO WU,TATJANA PAUNESKU,ERIC M. B. BROWN,ANGELA BABBO,CECILLE CRUZ,MOHAMMED ASLAM,VINAYAK DRAVID,GAYLE E. WOLOSCHAK 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2008 NANO Vol.3 No.1

This work demonstrates the assembly of TiO2 nanoparticles with attached DNA oligonucleotides into a 3D mesh structure by allowing base pairing between oligonucleotides. A change of the ratio of DNA oligonucleotide molecules and TiO2 nanoparticles regulates the size of the mesh as characterized by UV-visible light spectra, transmission electron microscopy (TEM) and atomic force microscopy (AFM) images. This type of 3D mesh, based on TiO2-DNA oligonucleotide nanoconjugates, can be used for studies of nanoparticle assemblies in materials science, energy science related to dye-sensitized solar cells, environmental science as well as characterization of DNA interacting proteins in the field of molecular biology. As an example of one such assembly, proliferating cell nuclear antigen protein (PCNA) was cloned, its activity was verified, and the protein was purified, loaded onto double strand DNA oligonucleotide-TiO2 nanoconjugates, and imaged by atomic force microscopy. This type of approach may be used to sample and perhaps quantify and/or extract specific cellular proteins from complex cellular protein mixtures based on their affinity for chosen DNA segments assembled into the 3D matrix.

Genetic Algorithm‑Based Analysis of the Efects of an Additional Damping Controller for a Doubly Fed Induction Generator

Aiguo Tan,Zhihan Tang,Xianbo Sun,Jianwei Zhong,Honghua Liao,Haibing Fang 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

In view of the problem that large-scale and high-penetration wind power access may weaken the stability of small interference in the power grid, this study proposes a novel additional damping controllers for the doubly-fed induction generator (DFIG) based on the genetic algorithm. A DFIG model and its control system is built, and the parameters of the controller are tuned using the genetic algorithm to optimize the control efect. Based on Western System Coordinating Council (WSCC) 3-machine 9-node system, multi-scenario simulation results verifes that the additional damping controller proposed in this study performs better to suppress the low-frequency oscillation than the power system stabilizer (PSS) installed on the synchronous generators which are farther to the disturbance point. Meanwhile, the proposed strategy is compared with the reactive power modulation control, which can provide a reference for engineering applications of an added DFIG damping controller.

Challenges in neuro-machine interaction based active robotic rehabilitation of stroke patients

Song, Aiguo,Yang, Renhuan,Xu, Baoguo,Pan, Lizheng,Li, Huijun Techno-Press 2014 Advances in robotics research Vol.1 No.2

Study results in the last decades show that amount and quality of physical exercises, then the active participation, and now the cognitive involvement of patient in rehabilitation training are known of crux to enhance recovery outcome of motor dysfunction patients after stroke. Rehabilitation robots mainly have been developing along this direction to satisfy requirements of recovery therapy, or focusing on one or more of the above three points. Therefore, neuro-machine interaction based active rehabilitation robot has been proposed for assisting paralyzed limb performing designed tasks, which utilizes motor related EEG, UCSDI (Ultrasound Current Source Density Imaging), EMG for rehabilitation robot control and feeds back the multi-sensory interaction information such as visual, auditory, force, haptic sensation to the patient simultaneously. This neuro-controlled and perceptual rehabilitation robot will bring great benefits to post-stroke patients. In order to develop such kind of robot, some key technologies such as noninvasive precise detection of neural signal and realistic sensation feedback need to be solved. There are still some grand challenges in solving the fundamental questions to develop and optimize such kind of neuro-machine interaction based active rehabilitation robot.

Rocaglamide-A Potentiates Osteoblast Differentiation by Inhibiting NF-κB Signaling

Li, Aiguo,Yang, Libin,Geng, Xiaolin,Peng, Xingmei,Lu, Tan,Deng, Yanjun,Dong, Yuzheng Korean Society for Molecular and Cellular Biology 2015 Molecules and cells Vol.38 No.11

Rheumatoid arthritis is a chronic inflammatory disease that leads to bone and cartilage erosion. The inhibition of osteoblast differentiation by the inflammatory factor TNF-${\alpha}$ is critical for the pathogenesis of rheumatoid arthritis. To modulate TNF-${\alpha}$ mediated inhibition of osteoblast differentiation is required to improve therapeutic efficacy of rheumatoid arthritis. Here, we explored the potential role of rocaglamide-A, a component of Aglaia plant, in osteoblast differentiation. Rocaglamide-A prevented TNF-${\alpha}$ mediated inhibition of osteoblast differentiation, and promoted osteoblast differentiation directly, in both C2C12 and primary mesenchymal stromal cells. Mechanistically, Rocaglamide-A inhibited the phosphorylation of NF-${\kappa}B$ component p65 protein and the accumulation of p65 in nucleus, which resulted in the diminished NF-${\kappa}B$ responsible transcriptional activity. Oppositely, overexpression of p65 reversed rocaglamide-A's protective effects on osteoblast differentiation. Collectively, rocaglamide-A protected and stimulated osteoblast differentiation via blocking NF-${\kappa}B$ pathway. It suggests that rocaglamide-A may be a good candidate to develop as therapeutic drug for rheumatoid arthritis associated bone loss diseases.

Safe Arm Using Compliant Hybrid Joints for Mobile Manipulators in Human-Symbiotic Environments

Zhijun Li,Aiguo Ming,Ning Xi,Jiangong Gu,Makoto Shimojo 한국과학기술원 인간친화 복지 로봇 시스템 연구센터 2005 International Journal of Assistive Robotics and Me Vol.6 No.1

  In this paper, a safe arm with compliant hybrid joints for human-friendly service robots is presented, which realizes human safety, absorbing impact force, and task fulfillment. The robot is composed of links covered with soft materials and hybrid joints, which can be put into active or passive mode as needed. In an unexpected or expected collision with human, the arising impulse force is attenuated effectively by the physical model, which is developed with hybrid joints and soft covering. Owing to the displacement of the links when the joint is passive, a recovery control algorithm has been developed for the end-effector to maintain its desired task position after the collision. The force attenuation property has been verified through collision experiments in that the capability of the proposed passive arm in overcoming the limitations of active compliance control has been demonstrated. Simulation results also showed that the proposed control method is useful for robot"s task fulfillment as well.

SO₂감지를 위한 NASICON 고체전해질 가스센서의 제조 및 특성 평가

배재철,Liu, aiguo,이상태,전희권,방영일,이덕동,허증수 경북대학교 센서기술연구소 2002 센서技術學術大會論文集 Vol.13 No.1

Study on Occurrence of Titanium Element in Anatase Ores of Shazi, Qinglong, Guizhou Province

Min Zhang,Aiguo Nie,Fei Xie,Zhuru Zhang 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.2

The tectonic position of anatase deposit in Shazi area, Qinglong, Guizhou Province is located at the transitional area between Yangtze Platform and the western part of South China orogenic belt. Three industrial ore bodies in this deposit are yielded above the limestone Karst unconformity of the Middle Permian Maokou Formation and at the bottom of Emeishan basalt. Genetic type of deposit is hot water -eluvium talus sedimentary which is related to the eruption of Emeishan basalt. Based on the analysis of chemistry, X-ray phase, electron probe and microscopic identification, etc., the data suggest that TiO2 in anatase ores are mainly present in the form of microgranular inclusions in silicate and quartz; secondly, Ti occurs as isomorphism in limonite; few are as independent minerals existing in the anatase with particle size greater than 0.04mm. According to the occurrence of Ti, it is determined that the anatase ores are extremely refractory, using conventional processing methods (heavy, magnetic, flotation) are not effective in enrichment anatase, but "roasting- acid leaching-alkaline leaching" beneficiation process works and obtain anatase with 42.32% TiO2. Extraction method can also enrich the associated element Sc, obtaining 99.99% scandium oxide products, and the leaching rate of Sc is 90%, which can produce iron oxide red and poly aluminum silicate salt (PSA) coagulant by-product. Mineral resources can be effectively developed and utilized without emission, which can obtain good environmental benefits.