The multifunctional RNA-binding protein hnRNPK is critical for the proliferation and differentiation of myoblasts

( Yongjie Xu ),( Rui Li ),( Kaili Zhang ),( Wei Wu ),( Suying Wang ),( Pengpeng Zhang ),( Haixia Xu ) 생화학분자생물학회(구 한국생화학분자생물학회) 2018 BMB Reports Vol.51 No.7

HnRNPK is a multifunctional protein that participates in chromatin remodeling, transcription, RNA splicing, mRNA stability and translation. Here, we uncovered the function of hnRNPK in regulating the proliferation and differentiation of myoblasts. hnRNPK was mutated in the C2C12 myoblast cell line using the CRISPR/Cas9 system. A decreased proliferation rate was observed in hnRNPK-mutated cells, suggesting an impaired proliferation phenotype. Furthermore, increased G2/M phase, decreased S phase and increased sub-G1 phase cells were detected in the hnRNPK-mutated cell lines. The expression analysis of key cell cycle regulators indicated mRNA of Cyclin A2 was significantly increased in the mutant myoblasts compared to the control cells, while Cyclin B1, Cdc25b and Cdc25c were decreased sharply. In addition to the myoblast proliferation defect, the mutant cells exhibited defect in myotube formation. The myotube formation marker, myosin heavy chain (MHC), was decreased sharply in hnRNPK-mutated cells compared to control myoblasts during differentiation. The deficiency in hnRNPK also resulted in the repression of Myog expression, a key myogenic regulator during differentiation. Together, our data demonstrate that hnRNPK is required for myoblast proliferation and differentiation and may be an essential regulator of myoblast function. [BMB Reports 2018; 51(7): 350-355]

Upregulation of miR-223 in the rat liver inhibits proliferation of hepatocytes under simulated microgravity

Yongjie Chen,Ji Xu,Chao Yang,Hongyu Zhang,Feng Wu,Jian Chen,Kai Li,Hailong Wang,Yu Li,Yinghui Li,Zhongquan Dai 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

Long-term spaceflight affects numerous organ systems in the body, including metabolic dysfunction. Recently, ample evidence has demonstrated that the liver is a vulnerable organ during spaceflight. However, the changes in hepatocyte proliferation and cell cycle control under microgravity remain largely unexplored. In the present study, we first confirmed that the serum levels of aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase, biochemical markers of liver function, were altered in rats under tail suspension (TS) conditions to simulate microgravity, as shown in previous reports. Next, we demonstrated that the cell proliferation activity, determined by Ki67, PCNA and PH3, was significantly decreased at the different TS time points (TS for 14, 28 and 42 days) compared with that in the control group. Consistently, the positive cell cycle regulators Ccna2, Ccnd1, Cdk1, Cdk2 and cyclin D3 were also significantly decreased in the TS groups as shown by quantitative real-time PCR and western blotting analysis. Subsequent analysis revealed that the aberrant hepatocyte proliferation inhibition under simulated microgravity was associated with the upregulation of miR-223 in the liver. We further found that miR-223 inhibited the proliferation of Hepa1-6 cells and identified CDK2 and CUL1 as its direct targets. In addition, the decreased expression of CDK2 and CUL1 was negatively correlated with the level of p27 in vitro and in vivo, which may have been responsible for retarding hepatocyte proliferation. Collectively, these data indicate that upregulation of miR-223 was associated with the inhibition of liver cell growth and reveal the role of miR-223 in rat hepatocyte proliferation disorders and the pathophysiological process under simulated microgravity.

Anterior Gradient 3 Promotes Breast Cancer Development and Chemotherapy Response

Qiao Xu,Ying Shao,Jinman Zhang,Huikun Zhang,Yawen Zhao,Xiaoli Liu,Zhifang Guo,Wei Chong,Feng Gu,Yongjie Ma 대한암학회 2020 Cancer Research and Treatment Vol.52 No.1

Purpose Anterior gradient 3 (AGR3) belongs to human anterior gradient (AGR) family. The function of AGR3 on cancer remains unknown. This research aimed to investigate if AGR3 had prognostic values in invasive ductal carcinoma (IDC) of breast cancer and could promote tumor progression. Materials and Methods AGR3 expression was detected in breast benign lesions, ductal carcinoma in situ and IDC by immunohistochemistry analysis. AGR3’s correlations with clinicopathological features and prognosis of IDC patients were analyzed. By cell function experiments, collagen gel droplet-embedded culture drug sensitivity test and cytotoxic analysis, AGR3’s impacts on proliferation, invasion ability, and chemotherapeutic drug sensitivity of breast cancer cells were also detected. Results AGR3 was up-regulated in luminal subtype of histological grade I-II of IDC patients and positively correlated with high risks of recurrence and distant metastasis. AGR3 high expression could lead to bone or liver metastasis and predict poor prognosis of luminal B. In cell lines, AGR3 could promote proliferation and invasion ability of breast cancer cells which were consistent with clinical analysis. Besides, AGR3 could indicate poor prognosis of breast cancer patients treated with taxane but a favorable prognosis with 5-fluoropyrimidines. And breast cancer cells with AGR3 high expression were resistant to taxane but sensitive to 5-fluoropyrimidines. Conclusion AGR3 might be a potential prognostic indicator in luminal B subtype of IDC patients of histological grade I-II. And patients with AGR3 high expression should be treated with chemotherapy regimens consisting of 5-fluoropyrimidines but no taxane.

Experimental studies on tool geometry in machining of nomex honeycomb core

Qihao Xu,Yi-Qi Wang,Yongjie Bao,Hang Gao 한국생산제조학회 2018 한국생산제조시스템학회 학술발표대회 논문집 Vol.2018 No.10

Glabridin Liposome Ameliorating UVB-Induced Erythema and Lethery Skin by Suppressing Inflammatory Cytokine Production

( Chijian Zhang ),( Yongjie Lu ),( Yong Ai ),( Xian Xu ),( Siyang Zhu ),( Bing Zhang ),( Minghui Tang ),( Lanyue Zhang ),( Tinggang He ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.4

Glabridin, a compound of the flavonoid, has shown outstanding skin-whitening and anti-aging properties, but its water insolubility limits its wide application. Therefore, glabridin liposome (GL) has been developed to improve its poor bioavailability, while there are few studies to evaluate its amelioration of UVB- induced photoaging. This study is performed to investigate the amelioration of GL against UVB- induced cutaneous photoaging. The prepared GL has a spheroidal morphology with an average diameter of 200 nm. The GL shows lower cytotoxicity than glabridin, but it has a more effective role in inhibition of melanin. Moreover, the application of GL can effectively relieve UV radiation induced erythema and leathery skin, associated with the down-regulated expression of inflammatory cytokines (TNF-α, IL-6 and IL-10). Taken together, these results demonstrate that GL has potentials as topical therapeutic agents against UVB radiation induced skin damage through inhibiting inflammation.

Mechanical Characteristics of Hybrid-Fiber-Reinforced Concrete Shaft Wall Structure Under Uneven Load

Zhishu Yao,Yongjie Xu,Ping Zhang,Yu Fang,Chen Wang,Naihao Diao,Kun Hu 한국콘크리트학회 2023 International Journal of Concrete Structures and M Vol.17 No.1

To prevent damage to shaft walls in mines due to uneven loading, the mechanical properties of a shaft wall structure made of hybrid-fiber-reinforced concrete were studied. First, through orthogonal testing, the optimal mix proportion of the hybrid-fiber-reinforced concrete was obtained. Subsequently, a numerical calculation model of the shaft wall structure under uneven loading was established. The calculation results showed that the structure exhibits a tensile stress under the action of uneven loading and that its bearing capacity can be improved using the hybrid-fiber-reinforced concrete. Based on the numerical simulation results, a calculation formula for the bearing capacity of the shaft wall was obtained by regression. Finally, a model test was conducted on the shaft lining structure. The results obtained were consistent with those obtained using the numerical simulation regression formula, confirming the reliability of the numerical simulation results. This study showed that a hybrid-fiber-reinforced concrete shaft wall structure can better withstand uneven loads and has improved brittle failure characteristics. Hybrid-fiber-reinforced concrete is an excellent material for deep shaft wall structures.

Research on a Robust Overset Grid Method for Load Calculation of Coaxial Rotor

Yang Yucheng,Guohua Xu,Shi Yongjie 한국항공우주학회 2022 International Journal of Aeronautical and Space Sc Vol.23 No.3

In this paper, a robust overset grid assembly technology suitable for the coaxial rotor in flow field calculation is established and two kinds of interpolation boundaries including so-called Max-hole boundary and Max-overlap boundary are proposed. The technology is applied to the computational fluid dynamics method based on the Reynolds-averaged Navier–Stokes equation to realize flow field simulation and aerodynamic performance calculation of coaxial rotor and overcome orphan point problem. Firstly, the pressure distribution of 30p30n airfoil is calculated and verified by experimental data. Through the high-efficient trimming method, the input of AH-G Helicopter rotor is obtained. The aerodynamic performance of AH-1G helicopter rotor is calculated and compared with experimental data. Finally, the input of coaxial rotor is also obtained by trimming method and flow field of the coaxial rotor in hover and the low advance ratio is calculated. The results show that the chimera method based on the Max-hole chimera boundary can be applied to obtain the aerodynamic characteristics of the coaxial rotor, effectively capturing the blade-vortex interference between rotors and rotor itself while aerodynamic performance cannot be accurately simulated under the Max-overlap chimera boundary.

A New Study on the Gap Effect of an Airfoil with Active Flap Control Based on the Overset Grid Method

Zhiyuan Hu,Guohua Xu,Yongjie Shi 한국항공우주학회 2021 International Journal of Aeronautical and Space Sc Vol.22 No.4

Rotors with active flap control have considerable potential in reducing vibration and noise and improving aerodynamic performance. However, due to the movement of the flap, there are unavoidable gaps between the components that will lead to significant changes in the aerodynamic characteristics. Moreover, considering the difficulties in motion modeling and the accuracy of the simulation of the flow field in such a narrow gap, carrying out related research is challenging; thus, there has been inadequate targeted research, and that which does exist requires supplementation. To carry out this challenging flow field simulation, the overset assembly algorithm proposed by the author in previous research is adopted in the present study. It is used to successfully assemble the narrow gap, and the accuracy of the simulation is fully verified by comparing the results with the actual experimental results and a grid study. Furthermore, to compensate for the lack of research and experiments on the gap effect, cases considering a complete range of gap widths from an absence of a gap to a width of 10% of the chord length are set up and carried out under the following three case groups: steady cases with a fixed trailing-edge deflection angle, unsteady cases in which only the trailing-edge flap is flapping, and full-motion cases characterized by the periodic flap of the main airfoil and the trailing-edge flap. The results show that the gap increases the drag of the trailing-edge flap and decreases aerodynamic efficiency, especially at low speeds and high angles of attack. Nevertheless, when the gap is unavoidable, there is a range of the gap width that makes unapparent the decrease of aerodynamic efficiency. Moreover, the decrease of aerodynamic efficiency can be reduced as much as possible by a well-designed gap region geometry to ensure that the airfoil and the trailing-edge flap fit together when moving.

Phase transformation induced resistive switching behavior in Al/Cu₂Se/Pt

Shania REHMAN,Kiwhan KIM,Yongji XU,Deok-Kee KIM 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Investigation of a Virtual Blade Method for Aerodynamic and Acoustic Prediction of Helicopter Rotors

Chi Zhang,Guohua Xu,Yongjie Shi 한국항공우주학회 2023 International Journal of Aeronautical and Space Sc Vol.24 No.2

A virtual blade method (VBM) combining the unsteady momentum source model with the computational fluid dynamics solver is applied in this work. The momentum source term is employed to replace the effect of the rotor blade on the air in the unsteady Reynolds-averaged Navier–Stokes equations, and the unsteady characteristics of the rotor flow field are accurately captured without body-fitted grids. The rotor aeroacoustic computation model is then combined with the Ffowcs Williams and Hawkings (FW–H) equation. Taking the Caradonna–Tung rotor, GIT rotor fuselage model, and AH-1/OLS rotor model as examples, the aeroacoustic computation effectiveness for blade tip vortex capturing in hover and rotor/fuselage aerodynamic interactions is validated by available experimental data. The results show that the VBM can accurately simulate the rotor wake, unsteady load, and aerodynamic noise at a low computational cost. Compared with the body-fitted grid method, the flow field computation time of the VBM is reduced by 3/4, and the amount of data for VBM/FW–H acoustic postprocessing is reduced by more than 90%.