Phosphodiesterase 4D contributes to angiotensin II-induced abdominal aortic aneurysm through smooth muscle cell apoptosis

Gao Ran,Guo Wenjun,Fan Tianfei,Pang Junling,Hou Yangfeng,Feng Xiaohang,Li Bolun,Ge Weipeng,Fan Tianhui,Zhang Tiantian,Lu Jiakai,Jing He,Jin Mu,Yan Chen,Wang Jing 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Abdominal aortic aneurysm (AAA) is a permanent expansion of the abdominal aorta that has a high mortality but limited treatment options. Phosphodiesterase (PDE) 4 family members are cAMP-specific hydrolyzing enzymes and have four isoforms (PDE4A-PDE4D). Several pan-PDE4 inhibitors are used clinically. However, the regulation and function of PDE4 in AAA remain largely unknown. Herein, we showed that PDE4D expression is upregulated in human and angiotensin II-induced mouse AAA tissues using RT-PCR, western blotting, and immunohistochemical staining. Furthermore, smooth muscle cell (SMC)-specific Pde4d knockout mice showed significantly reduced vascular destabilization and AAA development in an experimental AAA model. The PDE4 inhibitor rolipram also suppressed vascular pathogenesis and AAA formation in mice. In addition, PDE4D deficiency inhibited caspase 3 cleavage and SMC apoptosis in vivo and in vitro, as shown by bulk RNA-seq, western blotting, flow cytometry and TUNEL staining. Mechanistic studies revealed that PDE4D promotes apoptosis by suppressing the activation of cAMP-activated protein kinase A (PKA) instead of the exchange protein directly activated by cAMP (Epac). Additionally, the phosphorylation of BCL2-antagonist of cell death (Bad) was reversed by PDE4D siRNA in vitro, which indicates that PDE4D regulates SMC apoptosis via the cAMP-PKA-pBad axis. Overall, these findings indicate that PDE4D upregulation in SMCs plays a causative role in AAA development and suggest that pharmacological inhibition of PDE4 may represent a potential therapeutic strategy.

Structural health monitoring response reconstruction based on UAGAN under structural condition variations with few-shot learning

Gao Fan,Jun LI,Zhengyan He 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.30 No.6

Inevitable response loss under complex operational conditions significantly affects the integrity and quality of measured data, leading the structural health monitoring (SHM) ineffective. To remedy the impact of data loss, a common way is to transfer the recorded response of available measure point to where the data loss occurred by establishing the response mapping from measured data. However, the current research has yet addressed the structural condition changes afterward and response mapping learning from a small sample. So, this paper proposes a novel data driven structural response reconstruction method based on a sophisticated designed generating adversarial network (UAGAN). Advanced deep learning techniques including U-shaped dense blocks, self-attention and a customized loss function are specialized and embedded in UAGAN to improve the universal and representative features extraction and generalized responses mapping establishment. In numerical validation, UAGAN efficiently and accurately captures the distinguished features of structural response from only 40 training samples of the intact structure. Besides, the established response mapping is universal, which effectively reconstructs responses of the structure suffered up to 10% random stiffness reduction or structural damage. In the experimental validation, UAGAN is trained with ambient response and applied to reconstruct response measured under earthquake. The reconstruction losses of response in the time and frequency domains reached 16% and 17%, that is better than the previous research, demonstrating the leading performance of the sophisticated designed network. In addition, the identified modal parameters from reconstructed and the corresponding true responses are highly consistent indicates that the proposed UAGAN is very potential to be applied to practical civil engineering.

Structural health monitoring data anomaly detection by transformer enhanced densely connected neural networks

Gao Fan,Jun LI,Wupeng Chen 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.30 No.6

Guaranteeing the quality and integrity of structural health monitoring (SHM) data is very important for an effective assessment of structural condition. However, sensory system may malfunction due to sensor fault or harsh operational environment, resulting in multiple types of data anomaly existing in the measured data. Efficiently and automatically identifying anomalies from the vast amounts of measured data is significant for assessing the structural conditions and early warning for structural failure in SHM. The major challenges of current automated data anomaly detection methods are the imbalance of dataset categories. In terms of the feature of actual anomalous data, this paper proposes a data anomaly detection method based on data-level and deep learning technique for SHM of civil engineering structures. The proposed method consists of a data balancing phase to prepare a comprehensive training dataset based on data-level technique, and an anomaly detection phase based on a sophisticatedly designed network. The advanced densely connected convolutional network (DenseNet) and Transformer encoder are embedded in the specific network to facilitate extraction of both detail and global features of response data, and to establish the mapping between the highest level of abstractive features and data anomaly class. Numerical studies on a steel frame model are conducted to evaluate the performance and noise immunity of using the proposed network for data anomaly detection. The applicability of the proposed method for data anomaly classification is validated with the measured data of a practical supertall structure. The proposed method presents a remarkable performance on data anomaly detection, which reaches a 95.7% overall accuracy with practical engineering structural monitoring data, which demonstrates the effectiveness of data balancing and the robust classification capability of the proposed network.

Removal of NO by carbon-based catalytic reduction bed loaded with Mn induced by dielectric barrier discharge at low temperature

Fan Gao,Xingpeng Jin,Guicheng Wang,Luying Sun,Yujie Tan,Renxi Zhang,Weixuan Zhao,Jianyuan Hou,Ruina Zhang 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.1

The current paper reports on a newly developed DBD-Mn/FCRB hybrid system to explore the removal of NO<SUB>x </SUB> by reduction without adding reducing gas at low temperature (below 80℃). This technology was established with a fixed carbon-based reduction catalytic reduction bed loaded with manganese (Mn/FCRB) induced by dielectric barrier discharge (DBD). The NO conversion and N₂ selectivity in the new hybrid system reached 90.9 and 79.9%, respectively under 8% oxygen content, 1,200 J/L specific input energy (SIE), which were all higher than in the single DBD and DBD-FCRB systems, respectively. The Mn/FCRB was further characterized before and after activation by SEM, XRD and XPS. The possible reaction pathways of denitration were proposed through three processes based on the experimental results: direct denitration of active carbon atoms excited by plasma, reduction by adsorptive C(N) and C(O) complexes on the FCRB surface, and the reaction of nitrogen oxides with by-product CO. In addition, the results also showed that the new in-situ reduction denitration system had strong oxygen shock resistance and water resistance.

Evaluation of Inhibitory Potentials of Chinese Medicinal Plants on Platelet-Activating Factor (PAF) Receptor Binding

Gao Jun Fan,Byung Hoon Han,Young Hwa Kang,Man Ki Park 한국생약학회 2001 Natural Product Sciences Vol.7 No.2

Methanol extracts of eighty Chinese medicinal plants were investigated for plateletactivating factor (PAF) receptor binding inhibitory activity using rabbit platelet. Extracts of Cratoxylon ligustrinum, Kalimeris indica, Euonymus japonica, Ophiopogon japonicus, Gleditsia sinensis, Clausena lansium, Agave sisalana were found to exhibit significant inhibitory effects. Chloroform partition of the Methanol extract of Kalimeris indica was further fractionated by column chromatography to afford one strong active subfraction with 93.6% inhibition at a concentration of 100 ㎍/㎖.

SYMPOSIUM 1 : Treatment Strategy in Alcoholic Hepatitis

( Jian Gao Fan ) 대한간학회 2013 춘·추계 학술대회 (KASL) Vol.2013 No.1

Alcoholic liver disease is a major cause of morbidity among excessive alcohol drinkers, its spectrum of liver injury ranges from steatosis to varying stages of liver fibrosis and cirrhosis, and hepatitis can occur at any stage of alcoholic liver disease. Alcoholic hepatitis is a clinical-pathological syndrome characterized by a wide spectrum of clinical severity that results from consumption of large amount of alcohol during a sustained period of time in a subset of alcoholics. Currently, the treatment of alcoholic hepatitis remains a much discussed and controversial area of clinical Hepatology. The cornerstone of therapy for alcoholic hepatitis is lifetime abstinence of alcohol, with referral to an alcoholic rehabilitation program. However, even patients who remain abstinent are at risk at an increased risk for developing cirrhosis. The mortality rate of hospitalized patients with alcoholic hepatitis varies between 0% and 100%. Therefore, it is important to identify patients who benefit most from aggressive interventional therapy. Generally, patients with mild to moderate disease severity usually need not be treated with extraordinary measures, severe patients with the score of Maddrey discriminant function between 32 and 54 are recommend to use a dose of prednisolone (40 mg/d for 4 weeks then tapered over a 2-4 week) or pentoxifylline, these aggressive therapeutic agents seem to provide moderate survival benefit in patients with severe alcoholic hepatitis. In addition, patients with alcoholic hepatitis should be assessed for nutritional deficiencies and routine screened for cirrhosis. Physicians should be conversant with assessment and management of malnutrition and infection. Finally, timely referral to a liver transplant program for those patients who do did not respond to prednisone and pentoxifylline after 1 to 4 weeks treatment.

崔致遠과 韓中文化交流

高國藩(Gao Guo Fan),안영필(번역자) 한림대학교 아시아문화연구소 1998 아시아문화 Vol.- No.14

문학 : 논최치원의시 ( 論崔致遠的詩 )

고국번 ( Guo fan Gao ) 한국중국학회 1998 國際中國學硏究 Vol.1 No.-

해내고본 (海內孤本) 《 황률치언 (黃律梔言) 》 적 발현급기가치 (發現及其價値)

고국번(Guo Fan Gao) 중국어문연구회 1996 中國語文論叢 Vol.10 No.-

Computational analysis of blood flow and wall mechanics in a model of early atherosclerotic artery

Fan He,Lu Hua,Li-jian Gao 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2

In this paper, the model of the early atherosclerotic artery was introduced to investigate the blood flow and wall mechanics and the effects of atherosclerosis on neighboring healthy arteries. Under the assumptions of unsteady, laminar, Newtonian, viscous, and incompressible blood flow and linear-elastic, isotropic, and incompressible vessel wall, the finite element method was used to construct the fluid-structure interaction scheme. Results show that wall shear stress is lower, and cyclic strain is higher in the neighboring healthy arteries than those in the atherosclerotic artery. The hemodynamic and wall mechanical factors are disadvantageous to the healthy arteries and have negative effects. The mechanical changes induced by early atherosclerosis may cause the disease to spread to the healthy arteries. This work proves that early diagnosis and treatment are important in preventing the further development and propagation of atherosclerosis.