Graded-Three-Dimensional Cell-Encapsulating Hydrogel as a Potential Biologic Scaffold for Disc Tissue Engineering

Li Zhixiang,Zhang Yiwen,Zhao Yupeng,Gao Xubin,Zhu Zhonglian,Mao Yingji,Qian Taibao 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.5

BACKGROUND: Intervertebral disk (IVD) degeneration, which can cause lower back pain, is a major predisposing factor for disability and can be managed through multiple approaches. However, there is no satisfactory strategy currently available to reconstruct and recover the natural properties of IVDs after degeneration. As tissue engineering develops, scaffolds with embedded cell cultures have proved critical for the successful regeneration of IVDs. METHODS: In this study, an integrated scaffold for IVD replacement was developed. Through scanning electron microscopy and other mechanical measurements, we characterized the physical properties of different hydrogels. In addition, we simulated the physiological structure of natural IVDs. Nucleus pulposus (NP) cells and annulus fibrosusderived stem cells (AFSCs) were seeded in gelatin methacrylate (GelMA) hydrogel at different concentrations to evaluate cell viability and matrix expression. RESULTS: It was found that different concentrations of GelMA hydrogel can provide a suitable environment for cell survival. However, hydrogels with different mechanical properties influence cell adhesion and extracellular matrix component type I collagen, type II collagen, and aggrecan expression. CONCLUSION: This tissue-engineered IVD implant had a similar structure and function as the native IVD, with the inner area mimicking the NP tissue and the outer area mimicking the stratified annulus fibrosus tissue. The new integrated scaffold demonstrated a good simulation of disc structure. The preparation of efficient and regeneration-promoting tissueengineered scaffolds is an important issue that needs to be explored in the future. It is hoped that this work will provide new ideas and methods for the further construction of functional tissue replacement discs.

Large-scale comparative transcriptome analysis of Nicotiana tabacum response to Ralstonia solanacearum infection

Alariqi Muna,Wei Hao,Cheng Junqi,Sun Yiwen,Zhu Hanyue,Wen Tianwang,Li Yapei,Wu Chenglin,Jin Shuangxia,Cao Jinglin 한국식물생명공학회 2022 Plant biotechnology reports Vol.16 No.6

Tobacco bacterial wilt caused by Ralstonia solanacearum invades tobacco plants during the whole growth period afecting yield and quality. However, the transcriptome profling of tobacco plant in response to bacterial wilt has not been well studied. In this study, we identifed the transcriptional profles of bacterial wilt-resistant (ac Yanyan97) and -susceptible (ac Honghuadajinyuan) tobacco cultivars infected with R. solanacearum at six time points by RNA sequencing. Gene expression analysis showed that the resistant cultivar manifested a faster change in the expression of defense-related genes than the susceptible cultivar during R. solanacearum infection, by which more diferentially expressed genes (DEGs) were up-regulated rather than down-regulated at all time points. Functional analysis indicated that DEGs were involved in plant hormones, glutathione and secondary metabolic pathways associated with tobacco resistance to bacterial wilt induced by R. solanacearum. Through subsequent Short Time-series Expression Miner (STEM) and weighted correlation network (WGCNA) analyses, the phenylpropanoid metabolic pathway was identifed as a key pathway for tobacco defense against R. solanacearum infestation. In summary, our results provide transcriptomic profles of tobacco response to R. solanacearum infestation

한국어 학습자의 쓰기에 나타난 어휘 풍요도 연구-숙달도 측정 도구로써 어휘 풍요도 측정 가능성을 중심으로-

원미진 ( Won Mijin ),왕억문 ( Wang Yiwen ),주우동 ( Zhu Yutong ),왕호 ( Wang Hau ) 한국문학언어학회(구 경북어문학회) 2017 어문론총 Vol.71 No.-

본 연구는 중급, 고급 중국인 한국어 학습자들의 어휘 풍요도를 분석하여 이를 통해 학습자의 어휘 능력 발달을 측정할 수 있는 도구로써 쓰기 능력을 측정하는 지표로 사용할 수 있는가를 모색해 보고자 하였다. 이를 위해 본 연구에서 중국어권 중급, 고급 한국어 학습자들의 쓰기 평가 자료를 연구 대상으로 삼아서 학습자 작문 총 40편을 수집하여 어휘 풍요도를 분석하였다. 어휘 풍요도를 분석하기 위해 어휘 다양도, 어휘 밀도, 어휘 세련도를 측정하였다. 분석 결과, 중국인 학습자들의 글에 나타난 어휘 풍요도는 등급이 올라가도 다양도는 크게 달라지지 않는다는 것을 확인하였고, 밀도와 세련도에 있어서의 차이는 6급 정도의 고급 학습자가 되었을 때는 3,4 급의 중급 학습자와 어휘 사용에 있어 차이가 있다는 것을 확인하였다. 또한, 쓰기 점수에 영향을 미치는 어휘 풍요도 변수의 영향을 분석한 결과 어휘 밀도는 쓰기 점수를 30%이상 설명할 수 있는 변수이지만 어휘 다양도와 세련도는 쓰기 점수에 긍정적인 영향을 주는 변수가 아닌 것으로 드러났다. The purpose of this study is to prove whether the lexical richness of Korean learners` writing has correlation with their language development and to observe whether it can be used to measure their language proficiency. To find our the possibility of using the lexical richness score as a reliable measurement and standard of Korean learners` language proficiency, we collected 40 pieces of Chinese Korean learners` writing works from level 3 to level 6. We analyzed the lexical richness by lexical density, lexical diversity, and lexical sophistication, and discovered that level 6 learners` lexical density and lexical sophistication score were better than level 3 and level 4 learners` scores. Also, the hierarchical regression analysis was conducted to examine the relative influence of the 3 vocabulary measurements. Therefore, the results revealed that their lexical density has 30 % account with their writing scores while lexical diversity and lexical sophistication were found that no influence with writing scores. The implication of this study is to explore the possibility of measuring vocabulary richness as a measurement tool of writing scores for Korean language learners.

Investigation of the Effect Mechanism of Cutting Sequence on Spiral Milling of CFRP/Ti Laminates Under Ultrasonic-Assisted Conditions

Kai Yang,Jie Pan,Ziyang Cao,Yiwen Zhu 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.25 No.4

The hole-making mechanism of carbon fiber reinforced plastic (CFRP)/titanium alloy stacks is different from that of monolayer materials. In order to reveal the effects of different cutting sequence strategies on the hole-making quality and machining efficiency of the stacked materials, valuable insights are provided for the design of the stacking machining process and the selection of the most suitable cutting sequence. The researchers conducted ultrasonic vibration-assisted helical milling and conventional helical milling experiments with different milling parameters, and explored the basic influence mechanisms of CFRP → Ti and Ti → CFRP on the hole-making in both ways. The results show that different cutting sequences have significant effects on the axial force and chip morphology changes during CFRP/Ti stack machining. The dimensional accuracy and consistency of the holes cut from the Ti side are better, and the quality of the entrance and exit from the Ti side under the ultrasonically assisted condition is close to the quality level of the holes cut from the CFRP side under the normal helical milling, and the ultrasonically assisted condition plays a good role in improving the quality of the holes made. In addition, the tearing coefficients of CFRP hole entry/exit in both machining modes increased with the increase of feed per tooth in tangential direction and decreased with the increase of spindle speed. The tearing coefficients of entry/exit holes in CFRP direction were smaller than those in titanium direction.

Preparation of N-TiO2/RGO nanocomposites through sol-gel method

Yudi Ma,Shukun Wang,Wanlan Zheng,Xin Xue,Huie Liu,Shuang Chen,Yiwen Zhu 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.9

Nitrogen-doped TiO2 and reduced graphene oxide (RGO) nanocomposites (NTG) were prepared by solgel method followed by annealing treatment process under N2 atmosphere. The as-prepared NTG nanocomposite were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR) and ultraviolet-visible diffuse reflectance spectroscopy (DRS). The results indicate that the incorporation of nitrogen onto both RGO and TiO2 was accomplished simultaneously in the facile process. Nitrogen doping makes the light excitation range red shift and can enhance the electron-hole separation effectively. The photocatalytic activity of the as-prepared samples was evaluated through the degradation of methyl orange (MO) under visible light irradiation. The introduction of nitrogen increased the photodegradation activity, which can be indicated by the fitted apparent first-order kinetics rate constant k, increasing about four times from 0- NTG-450 to 15-NTG-450. The annealing treatment further increased the photodegradation activity about 1.5 times of 15NTG-450 for 15NTG-800.

Acupuncture for Osteoporosis: a Review of Its Clinical and Preclinical Studies

Tian Yimiao,Wang Lili,Xu Tianshu,Li Rui,Zhu Ruyuan,Chen Beibei,Zhang Hao,Xia Bingke,Che Yiwen,Zhao Dandan,Zhang Dongwei 사단법인약침학회 2022 Journal of Acupuncture & Meridian Studies Vol.15 No.5

Acupuncture has gained growing attention in the management of osteoporosis (OP). However, a comprehensive review has not yet been conducted on the efficacy and challenges of acupuncture in preliminary research and clinical trials. Therefore, an extensive literature search was conducted using electronic databases, including PubMed (www.ncbi.nlm.nih.gov/pubmed), CNKI (www.cnki.net), and Web of Science, for studies published from the beginning of 2000 to the end of May 2022. Combinations of synonyms for OP, acupuncture, traditional Chinese medicine, clinical trial, preclinical study, and animal experiments were searched. A total of 290 papers were consulted, including 115 reviews, 109 clinical observations, and 66 preclinical studies. There is accumulating evidence to support the beneficial role of acupuncture in preserving bone quality and relieving clinical symptoms based on clinical and preclinical investigations. The top ten most commonly used acupoints are BL23, ST36, BL20, BL11, CV4, GV4, SP 6, KI3, BL18, and GB39. The underlying mechanisms behind the benefits of acupuncture may be linked with the regulation of the hypothalamic-pituitary-gonadal (adrenal) axis and activation of the Wnt/β-catenin and OPG/RANKL/RANK signaling pathways. In summary, strong evidence may still come from prospective and well-designed clinical trials to shed light on the potential role of acupuncture in preserving bone loss. Future investigations are needed to explore the potential underlying mechanisms, long-term clinical efficacy, and compliance of acupuncture in OP management.