Insufficient radiofrequency ablation-induced autophagy contributes to the rapid progression of residual hepatocellular carcinoma through the HIF-1α/BNIP3 signaling pathway

( Wen-lei Xu ),( Shao-hong Wang ),( Wen-bing Sun ),( Jun Gao ),( Xue-mei Ding ),( Jian Kong ),( Li Xu ),( Shan Ke ) 생화학분자생물학회(구 한국생화학분자생물학회) 2019 BMB Reports Vol.52 No.4

Currently speaking, it is noted that radiofrequency ablation (RFA) has been the most widely used treatment for hepatocellular carcinoma (HCC) occurring in patients. However, accumulating evidence has demonstrated that the incidence of insufficient RFA (IRFA) may result in the identified rapid progression of residual HCC in the patient, which can greatly hinder the effectiveness and patient reported benefits of utilizing this technique. Although many efforts have been proposed, the underlying mechanisms triggering the rapid progression of residual HCC after IRFA have not yet been fully clarified through current research literature reviews. It was shown in this study that cell proliferation, migration and invasion of residual HepG2 and SMMC7721 cells were significantly increased after the IRFA was simulated in vitro. In other words, it is noted that IRFA could do this by enhancing the image of autophagy of the residual HCC cell via the HIF-1 α/BNIP3 pathway. Consequently, the down-regulation of BNIP3 may result in the inhibition of the residual HCC cell progression and autophagy after IRFA. Our present study results suggest that IRFA could promote residual HCC cell progression in vitro by enhancing autophagy via the HIF-1 α/BNIP3 pathway. For this reason, it is noted that the targeting of the BNIP3 may be useful in preventing the rapid growth and metastasis of residual HCC after IRFA. [BMB Reports 2019; 52(4): 277-282]

Numerical Analysis on Mechanical Property of Concrete Filled Steel Tube Reinforced Concrete (CFSTRC) Columns Subjected to ISO-834 Standard Fire

Lei Xu,Lei Xu,Wen-Da Wang,Jian-Gang Sun 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.4

The present study established a numerical investigation on the behavior of concrete filled steel tube reinforced concrete (CFSTRC) columns subjected to fire. A finite element analysis (FEA) model was built to simulate the performance of CFSTRC columns under combined loading and fire. The FEA model was verified by the experimental results of CFSTRC columns subjected to fire. The comparison demonstrated an acceptable accuracy for the proposed FEA model. Afterwards, the FEA model was used to analyze the failure modes, the redistribution of internal force, the changes and development of the stress and strain, and the contact stress between the tube and concrete of CFSTRC columns subjected to fire. Influencing factors that may affect the bearing capacity of the CFSTRC columns subjected to fire were analyzed. The bearing capacity and stiffness of the CFSTRC columns gradually decreased in the fire; the parameters such as the fire duration time, sectional dimension, slenderness ratio, and sectional core area ratio significantly influenced the bearing capacity of the CFSTRC columns. Finally, a simplified calculating formula was proposed to calculate the influence factors of the bearing capacity of the CFSTRC columns subjected to ISO-834 standard fire. The formula-calculated results were well in agreement with the finite element analysis results, which provide a simple and feasible method for evaluating the fire-resistance design of these types of components in practical engineering.

A metal oxide TFT gate driver with a single negative power source employing a boosting module

Yangang Xu,Jun-Wei Chen,Wen-Xing Xu,Lei Zhou,Wei-Jing Wu,Jianhua Zou,Miao Xu,Lei Wang,Junbiao Peng 한국정보디스플레이학회 2020 Journal of information display Vol.21 No.1

This paper presents a new gate driver integrated by In-Zn-O thin-film transistors (IZO TFTs) with the etch stop layer (ESL) structure, in which only a single negative power source is used on account of a new boosting module. The boosting module is controlled only by the VIN signal for generating a lower level than VSS. The proposed gate driver with 15 stages is fabricated through the IZO TFT process on a glass substrate to verify its function. The experiment results showed that the proposed gate driver can successfully output full-swing waveforms with resistive load RL=2 kΩ and capacitive load CL=30 pF at the 16.7 and 66.7 kHz clock frequencies, and can also output as small as 3.2 μs pulse width with little distortion, revealing good stability.

Virus-like Particles as Antiviral Vaccine: Mechanism, Design, and Application

Lei Zhang,Wen Xu,Xi Ma,XiaoJing Sun,JinBo Fan,Yang Wang 한국생물공학회 2023 Biotechnology and Bioprocess Engineering Vol.28 No.1

Virus-like particles (VLPs) are viral structural protein that are noninfectious as they do not contain viral genetic materials. They are safe and effective immune stimulators and play important roles in vaccine development because of their intrinsic immunogenicity to induce cellular and humoral immune responses. In the design of antiviral vaccine, VLPs based vaccines are appealing multifunctional candidates with the advantages such as self-assembling nanoscaled structures, repetitive surface epitopes, ease of genetic and chemical modifications, versatility as antigen presenting platforms, intrinsic immunogenicity, higher safety profile in comparison with live-attenuated vaccines and inactivated vaccines. In this review, we discuss the mechanism of VLPs vaccine inducing cellular and humoral immune responses. We outline the impact of size, shape, surface charge, antigen presentation, genetic and chemical modification, and expression systems when constructing effective VLPs based vaccines. Recent applications of antiviral VLPs vaccines and their clinical trials are summarized.

Distinct mutations in MLH1 and MSH2 genes in Hereditary Non-polyposis Colorectal Cancer (HNPCC) families from China

( Wen Qian Wei ),( Fang Qi Liu ),( Lei Liu ),( Zuo Feng Li ),( Xiao Yan Zhang ),( Fan Jiang ),( Qu Shi ),( Xiao Yan Zhou ),( Wei Qi Sheng ),( San Jun Cai ),( Xuan Li ),( Ye Xu ),( Peng Nan ) 생화학분자생물학회(구 한국생화학분자생물학회) 2011 BMB Reports Vol.44 No.5

Hereditary non-polyposis Colorectal Cancer (HNPCC) is an autosomal dominant inheritance syndrome. HNPCC is the most common hereditary variant of colorectal cancer (CRC), which accounts for 2-5% CRCs, mainly due to hMLH1 and hMSH2 mutations that impair DNA repair functions. Our study aimed to identify the patterns of hMSH2 and hMLH1 mutations in Chinese HNPCC patients. Ninety-eight unrelated families from China meeting Amsterdam or Bethesda criteria were included in our study. Germline mutations in MLH1 and MSH2 genes, located in the exons and the splice-site junctions, were screened in the 98 probands by direct sequencing. Eleven mutations were found in ten patients (11%), with six in MLH1 (54.5%) and five in MSH2 (45.5%) genes. One patient had mutations in both MLH1 and MSH2 genes. Three novel mutations in MLH1 gene (c.157_160delGAGG, c.2157dupT and c.-64G>T) were found for the first time, and one suspected hotspot in MSH2 (c.1168C>T) was revealed. [BMB reports 2011; 44(5): 317-322]

Non-contact Coculture Reveals a Comprehensive Response of Chondrocytes Induced by Mesenchymal Stem Cells Through Trophic Secretion

Lei Xu,Yuxi Wu,Yanli Liu,Yan Zhou,Zhaoyang Ye,Wen-Song Tan 한국조직공학과 재생의학회 2018 조직공학과 재생의학 Vol.15 No.1

Coculture between mesenchymal stem cells (MSCs) and chondrocytes has significant implications in cartilage regeneration. However, a conclusive understanding remains elusive. Previously, we reported that rabbit bone marrowderived MSCs (rbBMSCs) could downregulate the differentiated phenotype of rabbit articular chondrocytes (rbACs) in a non-contact coculture system for the first time. In the present study, a systemic investigation was performed to understand the biological characteristics of chondrocytes in coculture with MSCs. Firstly, cells (MSCs and chondrocytes) from different origins were cocultured in transwell system. Different chondrocytes, when cocultured with different MSCs respectively, consistently demonstrated stimulated proliferation, transformed morphology and declined glycosaminoglycan secretion of chondrocytes. Next, cell surface molecules and the global gene expression of rbACs were characterized. It was found that cocultured rbACs showed a distinct surface molecule profile and global gene expression compared to both dedifferentiated rbACs and rbBMSCs. In the end, cocultured rbACs were passaged and induced to undergo the chondrogenic redifferentiation. Better growth and chondrogenesis ability were confirmed compared with control cells without coculture. Together, chondrocytes display comprehensive changes in coculture with MSCs and the cocultured rbACs are beneficial for cartilage repair.

Chinese Society of Allergy Guidelines for Diagnosis and Treatment of Allergic Rhinitis

Lei Cheng,Jianjun Chen,Qingling Fu,Shaoheng He,Huabin Li,Zheng Liu,Guolin Tan,Zezhang Tao,Dehui Wang,Weiping Wen,Rui Xu,Yu Xu,Qintai Yang,Chonghua Zhang,Gehua Zhang,Ruxin Zhang,Yuan Zhang,Bing Zhou,Do 대한천식알레르기학회 2018 Allergy, Asthma & Immunology Research Vol.10 No.4

Allergic rhinitis (AR) is a global health problem that causes major illnesses and disabilities worldwide. Epidemiologic studies have demonstrated that the prevalence of AR has increased progressively over the last few decades in more developed countries and currently affects up to 40% of the population worldwide. Likewise, a rising trend of AR has also been observed over the last 2-3 decades in developing countries including China, with the prevalence of AR varying widely in these countries. A survey of self-reported AR over a 6-year period in the general Chinese adult population reported that the standardized prevalence of adult AR increased from 11.1% in 2005 to 17.6% in 2011. An increasing number of original articles and imporclinical trials on the epidemiology, pathophysiologic mechanisms, diagnosis, management and comorbidities of AR in Chinese subjects have been published in international peer-reviewed journals over the past 2 decades, and substantially added to our understanding of this disease as a global problem. Although guidelines for the diagnosis and treatment of AR in Chinese subjects have also been published, they have not been translated into English and therefore not generally accessible for reference to non-Chinese speaking international medical communities. Moreover, methods for the diagnosis and treatment of AR in China have not been standardized entirely and some patients are still treated according to regional preferences. Thus, the present guidelines have been developed by the Chinese Society of Allergy to be accessible to both national and international medical communities involved in the management of AR patients. These guidelines have been prepared in line with existing international guidelines to provide evidence-based recommendations for the diagnosis and management of AR in China.

Mitochondrial NDUFA4L2 attenuates the apoptosis of nucleus pulposus cells induced by oxidative stress via the inhibition of mitophagy

Wen-Ning Xu,Huo-Liang Zheng,Run-Ze Yang,Tao Liu,Wei Yu,Xin-Feng Zheng,Bo Li,Sheng-Dan Jiang,Lei-Sheng Jiang 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

The main pathological mechanism of intervertebral disc degeneration (IVDD) is the programmed apoptosis of nucleus pulposus (NP) cells. Oxidative stress is a significant cause of IVDD. Whether mitophagy is induced by strong oxidative stress in IVDD remains to be determined. This study aimed to investigate the relationship between oxidative stress and mitophagy and to better understand the mechanism of IVDD in vivo and in vitro. To this end, we obtained primary NP cells from the human NP and subsequently exposed them to TBHP. We observed that oxidative stress induced mitophagy to cause apoptosis in NP cells, and we suppressed mitophagy and found that NP cells were protected against apoptosis. Interestingly, TBHP resulted in mitophagy through the inhibition of the HIF-1α/NDUFA4L2 pathway. Therefore, the upregulation of mitochondrial NDUFA4L2 restricted mitophagy induced by oxidative stress. Furthermore, the expression levels of HIF-1α and NDUFA4L2 were decreased in human IVDD. In conclusion, these results demonstrated that the upregulation of NDUFA4L2 ameliorated the apoptosis of NP cells by repressing excessive mitophagy, which ultimately alleviated IVDD. These findings show for the first time that NDUFA4L2 and mitophagy may be potential therapeutic targets for IVDD.

Numerical Analysis on Structural Behaviors of Concrete Filled Steel Tube Reinforced Concrete (CFSTRC) Columns Subjected To 3-side Fire

Lei Xu,Ming-Tao Wang,Yan-Hong Bao,Wen-Da Wang 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.4

The structural behaviors of concrete filled steel tube reinforced concrete (CFSTRC) columns, which were exposed to a 3- side fire were discussed by using the non-linear finite element analysis (FEA) software ABAQUS. Details of the temperature distribution, fire resistance, failure modes, redistribution of internal force, contact stress between the steel tube and the concrete (both inside and outside of the steel tube), and the development of stress and strain within the CFSTRC columns subjected to a 3-side fire were revealed. The factors that may have affected the fire resistance of the CFSTRC columns exposed to threeside fire were analyzed. Based on the above research, the present study observed uniaxial symmetry on the cross-sectional thermal distribution of the CFSTRC, wherein a significantly lower temperature on the unexposed side was observed as compared to the exposed side. The two side verges of the surface, which were not exposed to fire, exhibited the lowest temperature. Following the end of the heating, the maximum temperature difference reached about 1065oC. The large temperature difference would bring non-uniform thermal stress and strain, and accidental eccentricity. In addition, the existence of concrete inside and outside of the steel tube prevented the steel tube from occurring local buckling, and the failure modes of CFSTRC columns acted as overall bucking. Parameters such as the fire load ratio, sectional dimension, slenderness ratio, sectional core area ratio, and external concrete compression strength significantly influenced the fire resistance of the CFSTRC columns. Finally, a simplified calculating formula was proposed to calculate the fire resistance influence factors of the CFSTRC columns subjected to three-sid fire. The formula-calculated results were well in agreement with the finite element analysis results, thereby providing a simple and feasible method for evaluating the fire-resistance design of these types of components in practical engineering.

Monitoring and control of wind-induced vibrations of hanger ropes of a suspension bridge

Xu G. Hua,Zheng Q. Chen,Xu Lei,Qin Wen,Hua W. Niu 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.23 No.6

In August 2012, during the passage of the typhoon Haikui (1211), large amplitude vibrations were observed on long hangers of the Xihoumen suspension Bridge, which destroyed a few viscoelastic dampers originally installed to connect a pair of hanger ropes transversely. The purpose of this study is to identify the cause of vibration and to develop countermeasures against vibration. Field measurements have been conducted in order to correlate the wind and vibration characteristics of hangers. Furthermore, a replica aeroelastic model of prototype hangers consisting of four parallel ropes was used to study the aeroelastic behavior of hanger ropes and to examine the effect of the rigid spacers on vibration mitigation. It is shown that the downstream hanger rope experiences the most violent elliptical vibration for certain wind direction, and the vibration is mainly attributed to wake interference of parallel hanger ropes. Based on wind tunnel tests and field validation, it is confirmed that four rigid spacers placed vertically at equal intervals are sufficient to suppress the wake-induced vibrations. Since the deployment of spacers on hangers, server hanger vibrations and clash of hanger ropes are never observed.