Hypermethylation of Frizzled1 is associated with Wnt/β-catenin signaling inactivation in mesenchymal stem cells of patients with steroid-associated osteonecrosis

Zhibo Sun,Jing Jiao,Feng Liu,Yue Yang,Shanfeng Zhang,Zhenhua Fang,Zhipeng Dai,Zhibo Sun 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

The Wnt/β-catenin signaling pathway is associated with the pathogenesis of steroid-induced osteonecrosis. Our investigation studied whether aberrant CpG island hypermethylation of the FZD1 gene was present in patients with osteonecrosis of the femoral head (ONFH), which results in Wnt/β-catenin signaling inactivation and subsequent cell dysfunction. Bone marrow was collected from the proximal femurs of patients with steroid-associated ONFH (n = 21) and patients with new femoral neck fractures (n = 22), and then mesenchymal stem cells (MSCs) were isolated. We investigated cell viability, the transcription and translation levels of Wnt/β-catenin signaling-related genes, the extent of methylation at CpG islands of the FZD1 promoter, and the osteogenic and adipogenic differentiation abilities of MSCs from the control group and from the ONFH group treated with or without 5′-Aza-dC. According to the results, MSCs from the ONFH group showed a reduced proliferation ability, low transcription and translation levels of FZD1, inhibition of the Wnt/β-catenin signaling pathway, weakened osteogenesis and enhanced adipogenesis ability. Aberrant CpG island hypermethylation of FZD1 was observed in the ONFH group. Treatment with 5’-Aza-dC resulted in de novo FZD1 expression, reactivation of the Wnt/β-catenin signaling pathway and promotion of osteogenesis. Taken together, our study not only provides novel insights into the regulation of the Wnt/β-catenin signaling pathway in this disease but also reveals potential for the use of demethylating agents for the treatment of GC-associated ONFH.

Structural Design Verification of Large-Scale Complex Machine Tools Using Topology Optimization

Zhibo Zhang,Hocheol Lee,Syed Azkar Ul Hasan,Woosang Park 한국생산제조학회 2016 한국생산제조시스템학회 학술발표대회 논문집 Vol.2016 No.10

Study of Material Removal Behavior during Laser-assisted Ultrasonic Dressing of Diamond Wheel

Zhibo Yang,Shiyu Zhang,Junchen Hu,Zhen Zhang,Kaiqiang Li,Bo Zhao 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.7 No.1

Laser-assisted ultrasonic dressing (LUD) of the removal behavior of diamond wheel material is investigated by simulation and experimental method. The finite element model of diamond wheel is constructed for simulation during LUD. The effect of parameters of LUD process on the dressing force is discussed according to the simulation results. LUD experiments of diamond wheels are carried out after obtaining optimization of parameter. The dressing force obtained from simulation and experiments are compared. It is found that the variation tendency of simulated dressing force is in agreement with the experimental result. This indicates that the simulation results can be effectively used for the selection of process’ parameters.

Temporal and spatial characteristics of coal-mine microseism based on single-link cluster

Zhibo Zhang,Enyuan Wang,Enyuan Wang 한국지질과학협의회 2017 Geosciences Journal Vol.21 No.2

Single-link cluster is introduced into mine microseism monitoring from a seismology point of view. The changes in spatial correlation length of mine microseismic events at different spatial scales are analyzed, and the underlying mechanisms are explained. The results show that large-energy microseismic events often occur after the spatial correlation length drops to a low value when the spatial scale is large. The larger the energy of microseismic events is, the more obvious the law is. Large-energy microseismic events occur after the spatial correlation length exhibits the power-law growth phenomenon, when the spatial scale becomes small. The smaller the spatial scale is, the more obvious the law is. The reason for this property is that microseismic events exhibit the space aggregation phenomenon before a large-energy microseismic event occurs, resulting in decreases in spatial correlation length when the spatial scale is large. By contrast, when the spatial scale is small, the spatial correlation degree of regional microseismic sources is high. Small-energy microseismic events occur gradually with concentration in low-intensity regions, and a large number of small cracks are produced before a large microseismic event occurs. The microseismic source is dispersed again once the regional stress is released. The entire system achieves a critical state. There is small cracks coalescence at a particular moment, which triggers a large-energy microseismic event. Therefore, it exhibits the phenomenon of power-law growth of the correlation length before the occurrence of the large-energy microseismic event. Moreover, statistical analysis of the bond length and frequency of SLC is performed. The result is that three non-scale ranges are identified. The turning points of the first two nonscale ranges are 180 m and 240 m, respectively, while the turning points of the second and third non-scale ranges are both approximately 450 m. The difference between the first turning points is due to the artificial disturbance, while the second turning point is affected by the geological environment.

A pilot study of gonadotropin-releasing hormone agonist combined with aromatase inhibitor as fertility-sparing treatment in obese patients with endometrial cancer

Zhibo Zhang,Huifang Huang,Fengzhi Feng,Jinhui Wang,Ninghai Cheng 대한부인종양학회 2019 Journal of Gynecologic Oncology Vol.30 No.4

Objective: This study aims to evaluate the effects and pregnancy outcomes of gonadotropin-releasing hormone agonist (GnRH agonist) combined with aromatase inhibitor (AI) in preserving the fertility of obese women with grade 1 endometrial cancer (EC). Methods: This study recruited obese EC patients who wished to preserve their fertility. The treatment regimen consisted of intramuscular GnRH agonist 3.75 mg every 4 weeks and oral AI 2.5 mg daily. The maintenance regimen was the same as the initial treatment regimen. Primary outcomes included response rate, time to complete response (CR), and time to recurrence; pregnancy outcomes included the time to pregnancy, pregnancy rate and live birth rate. Results: Six obese patients with EC were included in this study, with the age (mean±standard deviation [SD]) of 30.5±3.3 years and body mass index (mean±SD) of 35.0±1.4 kg/m2. CR rate was 100%, and time to CR was 3–6 months. None of the patients had recurrence after a median follow-up of 4.0 years (range, 1.3–7.0 years). The most common side effects were menopause-like symptoms. Among these patients, no weight gain was observed during treatment. The pregnancy rate and live birth rate was 50.0% and 75.0%, respectively, with a median time to pregnancy of 2.4 years (range, 1.0–5.5 years). Conclusion: The combination of GnRH agonist and AI demonstrated promising long-term effect in young obese EC patients who wished to preserve their fertility. No weight gain side effects were observed. Further studies with a larger sample size are needed to fully evaluate this novel treatment regimen.

Properties on $q$-difference Riccati equation

Zhibo Huang,Ran-Ran Zhang 대한수학회 2018 대한수학회보 Vol.55 No.6

In this paper, we investigate a certain type of $q$-difference Riccati equation in the complex plane. We prove that $q$-difference Riccati equation possesses a one parameter family of meromorphic solutions if it has three distinct meromorphic solutions. Furthermore, we find that all meromorphic solutions of $q$-difference Riccati equation and corresponding second order linear $q$-difference equation can be expressed by $q$-gamma function if this $q$-difference Riccati equation admits two distinct rational solutions and $q\in\mathbb{C}$ such that $0<|q|<1$. The growth and value distribution of differences of meromorphic solutions of $q$-difference Riccati equation are also treated.

The Relationship between Watching Motivation, Perceived Value, Place Attachment and Behavioral Loyalty: A Case of China Tennis Open

( Qiang Zhang ),( Zhibo Tian ),( Jianmin Shi ),( Wangda Guo ) 아시아스포츠융합과학회 2021 Asia Pacific Journal of Applied Sport Sciences Vol.2 No.2

PURPOSE The purpose of this study is to investigate a behavioral loyalty model of China Tennis Open spectators and validate the relationships among spectators’’ watching motivation, perceived value, place attachment and behavioral loyalty. METHOD The spectators at the China Tennis Open were targeted as the main research sample. A total of 400 questionnaires were collected. The collected data was analyzed by means of descriptive statistics, confirmatory factor analysis, structural equation modeling, and significance test of difference. RESULT (1) Motivation has a positive effect on perceived value and place attachment, but the behavioral loyalty is not affected. (2) Perceived value directly influence on behavioral loyalty. (3) Place attachment directly influence on behavioral loyalty. CONCLUSION Motivation has a limited influence on the behavioral loyalty. Place attachment and perceived value are important factors in behavioral loyalty of China Tennis Open spectators. The results of this study provides some practical suggestions for the organization, management of tennis events and a direction for future research.

Meromorphic solutions of a complex difference equation of Malmquist type

Ran-Ran Zhang,Zhibo Huang 대한수학회 2014 대한수학회보 Vol.51 No.6

In this paper, we investigate the finite order transcendental meromorphic solutions of complex difference equation of Malmquist type n ∏ i=1 f(z + ci) = R(z, f), where c1, . . ., cn ∈ C\ {0}, and R(z, f) is an irreducible rational function in f(z) with meromorphic coefficients. We obtain some results on defi- ciencies of the solutions. Using these results, we prove that the growth order of the finite order solution f(z) is 1, if f(z) has Borel exceptional values a(∈ C) and 1. Moreover, we give the forms of f(z).

Damage detection using the improved Kullback-Leibler divergence

Shaohua Tian,Xuefeng Chen,Zhibo Yang,Zhengjia He,Xingwu Zhang 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.48 No.3

Structural health monitoring is crucial to maintain the structural performance safely. Moreover, the Kullback-Leibler divergence (KLD) is applied usually to asset the similarity between different probability density functions in the pattern recognition. In this study, the KLD is employed to detect the damage. However the asymmetry of the KLD is a shortcoming for the damage detection, to overcoming this shortcoming, two other divergences and one statistic distribution are proposed. Then the damage identification by the KLD and its three descriptions from the symmetric point of view is investigated. In order to improve the reliability and accuracy of the four divergences, the gapped smoothing method (GSM) is adopted. On the basis of the damage index approach, the new damage index (DI) for detect damage more accurately based on the four divergences is developed. In the last, the grey relational coefficient and hypothesis test (GRCHT) is utilized to obtain the more precise damage identification results. Finally, a clear remarkable improvement can be observed. To demonstrate the feasibility and accuracy of the proposed method, examples of an isotropic beam with different damage scenarios are employed so as to check the present approaches numerically. The final results show that the developed approach successfully located the damaged region in all cases effect and accurately.

마이크로 프레넬 렌즈 구조의 제조 설계 통합적 접근 방법

이호철(Hocheol Lee),장지박(Zhibo Zhang),이창은(Changeun Lee),김동영(Dongyoung Kim) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.5