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Preparation and Improvation of Nanophase Artificial Bone Composite Scaffold and Relevant Study on Properties

Chinese Journal of Biomedical Engineering(English Edition) 2009年第3期18卷 129-138页

作者： deng yun gu han-qing Tianjin Medical University Tianjin 300070 China

Objective：To prepare nanophase artificial bone composite scaffold based on bionics theory, and probe into how different content ratio between collagen and inorganic part as well as different molecular weight of conglutinant agent influence microstrueture and properties of the scaffold. Methods： Lead calcic inorganic molecules to deposite onto self-assembled collagen template during coprecipitation under certain reactive conditions such as content ratio and pH value of environment, and then nanophase collagen/calcic salt is obtained. In order to improve the mechanical properties, poly lactic acid （PLLA） which has stable equal properties and controllable biodegradable activities is chosen as conglutinant agent, and then the aimed artificial bone scaffold （nanophase collagen/calcic salt/PLLA composite） is accomplished. After preparation liquid displacement method with isoproanol alcohol, scanning electron microscopic （SEM） , transmission electron microscope （TEM）, fourier transform infrared spectrometry （FTIR）, mechanical testing system are performed to test porosity and density, morphology, conformation, composition and mechanical property, respectively. Results：The artificial synthesized bone composite scaffold is mainly composed of collagen and calcium phosphate partly displaced with B-type carbonate. The crystallinity is low, and the crystal size reaches nanometer which is similar to natural bone. PLLA used effectively improves the mechanical property which can reach at the floor level of cancellous standard, and develops three-dimensional-porous structure with high porosity of 80%. According to the comparison it can be seen that content ratio between collagen and calcic inorganic salt as well as addition of conglutinant PLLA all have an effect on microstructure of the synthesized scaffold, additionally molecular weight of PLLA has an effect on mechanical properties. Conclusion ：The nanophase artificial bone composite scaffold synthesized by biomimetic process is o

关键词： biomineralization self-assemble nanophase collagen calcium phosphate PLLA

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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 249-256页

作者： qing-yun Fang Chengyihan gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Polydopamine/Imogolite Nanotubes(PDA/INTs)Interlayer Modulated Thin Film Composite Forward Osmosis Membrane for Minimizing Internal Concentration Polarization

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Chinese Journal of Polymer Science 2022年第10期40卷 1233-1241,I0010页

作者： Jian-Chen han Shao-Fei Wang Ran deng qing-yun Wu School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Faculty of Materials Science and Chemical Engineering Ningbo UniversityNingbo 31521China

Forward osmosis(FO)as an energy-saving membrane process has attracted much attention in food concentration,water treatment,and *** film composite(TFC)membrane is the most popular FO membrane,but it suffers from the internal concentration polarization(ICP),which significantly limits the water flux and FO *** this report,we demonstrate a novel and high-performing thin film nanocomposite(TFN)membrane that employs a hydrophilic interlayer composed of imogolite nanotubes(INTs)and polydopamine(PDA).The INTs can be adhered to the porous substrate by the self-polymerization of PDA,and the as-prepared PDA/INTs interlayer displays a nanostructured network with outstanding *** detailed investigation was conducted to understand the relationship between the structure and property of the PDA/INTs interlayer and the morphology and performance of the TFN *** TFN membrane with the PDA/INTs interlayer performs a thinner and smoother polyamide selective ***,the TFN membrane shows a water flux of 18.38 L·m^(-2)·h^(-1),which is 2.18 times of the pristine TFC ***,the TFN membrane has a minimized structural parameter(577μm),almost a half of that of the pristine one(949μm).It reveals that the ICP effect of TFC membrane can be effectively alleviated by using a hydrophilic PDA/INTs *** TFN membrane with a satisfactory water permeability is promising in terms of future applications.

关键词： Interlayer Forward osmosis Internal concentration polarization Nanotube Thin film composite membrane

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Characteristics and mechanism investigation on drag reduction of oblique riblets

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Journal of Central South University 2017年第6期24卷 1379-1386页

作者： gu yun-qing FAN Tian-xing MOU Jie-gang WU deng-hao ZHENG Shui-hua College of Mechanical and Engineering Zhejiang University of TechnologyHangzhou 310014China Zhijiang College Zhejiang University of TechnologyHangzhou 310024China Institute National Polytechnique of Grenoble Joseph Fourier UniversityGrenoble 38031France

This work primarily focuses on the drag reduction characteristics and mechanism investigation of oblique riblets. First, a calculation model of the oblique riblets surface is established, and Reynolds stress model(RSM) turbulence model is used for numerical simulation of the oblique riblets flow field. Subsequently, the influence of inclination angle between flow direction and arrangement direction of riblets on friction resistance and drag reduction rate is further analyzed. Through the investigation of the distribution of shear stress, pressure stress and velocity in oblique riblets boundary layer, the oblique riblets drag reduction mechanism is finally revealed. Results show that, with increase of velocity and inclination angle, the pressure resistance increases obviously, along with the decreasing of the viscous resistance distinctly. The maximum drag reduction rate of the oblique riblets is 7.33%. Moreover, when the inclination angle increases, the wall shear stress reduces on oblique riblets surface; while differential pressure increases at both sides of oblique riblets tips. In addition, when inclination angle is small, the secondary vortex at oblique riblets tips will disappear soon. New vortices will be formed inside the oblique riblets and cause the decrease of viscosity resistance. Thus, oblique riblets show a better drag reduction effect and have an effective control on boundary layer.

关键词： oblique riblets drag reduction Reynolds stress model (RSM) secondary vortex numerical simulation

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Study on dynamic response of multi-degree-of-freedom explosion vessel system under impact load

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Defence Technology（防务技术） 2020年第4期16卷 777-786页

作者： yun-hao Hu Wen-bin gu Jian-qing Liu Jing-lin Xu Xin Liu Yang-ming han Zhen-xiong Wang College of Field Engineering Army Engineering University of PLANanjing 210007China Unit No.78102 of PLA Chengdu 610031China Unit No.31696 of PLA Jinzhou 121017China Research Institute of Chemical Defense Beijing 102205China

In order to study the dynamic response and calculate the axial dynamic coefficient of the monolayer cylindrical explosion vessel,the wall of vessel is simplified as a multi-degree-of-freedom(MDoF) undamped elastic foundation *** the coupled motion equation and using Duhamel's integrals,the solutions in generalized coordinates of the equations under exponentially decaying loads,square wave loads and triangular wave loads are *** solutions are consistent in form with the solutions of single-degree-of-freedom(SDoF) undamped forced vibration simplified *** on the model,equivalent MDoF design method(also called MDoF dynamic coefficient method) of cylindrical explosion vessel is *** traditional method can only predict the dynamic coefficient of torus portion around the explosion center,but this method can predict that of the vessel wall at any axial n dividing point *** is verified that the prediction accuracy of this model is greatly improved compared with the SDoF model by comparing the results of this model with SDoF model and numerical simulation in different working ***,the prediction accuracy decreases as the scaled distance decreases and approaches the end of the vessel,which is related to the accuracy of the empirical formula of the implosion load,the simplification of the explosion load direction,the boundary conditions,and the loading time difference.

关键词： Explosion vessel Dynamic response Vibration analysis Dynamic coefficient Load feature

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Downregulation of miR-193a-5p correlates with lymph node metastasis and poor prognosis in colorectal cancer

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World Journal of Gastroenterology 2014年第34期20卷 12241-12248页

作者： Peng Zhang deng-Bo Ji Hai-Bo han yun-Fei Shi Chang-Zheng Du Jin gu Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Colorectal SurgeryPeking University Cancer Hospital and Institute Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of Cell BiologyPeking University Cancer Hospital and Institute Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of PathologyPeking University Cancer Hospital and Institute

AIM: To investigate the correlation of miR-193a-5p with lymph node metastasis and postoperative survival of colorectal cancer (CRC) patients.

关键词： miR-193a-5p Colorectal cancer Lymph node metastasis Prognosis Biomarker

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Effects of Different Temperature and Time Durations of Virus Inactivation on Results of Real-time Fluorescence PCR Testing of COVID-19 Viruses

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Current Medical Science 2020年第4期40卷 614-617页

作者： Ze-gang WU Hong-yun ZHENG Jian gu Feng LI Rui-long LV Ya-yun deng Wan-zhou XU Yong-qing TONG Department of Clinical Laboratory Rentnin Hospital of Wuhan UniversityWuhan 430060China

Summary:The novel coronavirus SARS-CoV-2 caused an outbreak of pneumonia in Wuhan,Hubei province of China in January *** study aims to investigate the effects of different temperature and time durations of virus inactivation on the results of PCR testing for *** patients at the Renmin Hospital of Wuhan University suspected of being infected with SARS-CoV-2 were selected on February 13,2020 and throat swabs were *** swabs were stored at room tempcrature(20-25℃),then divided into aliquots and subjected to different temperature for different periods in order to inactivate the viruses(56℃for 30,45,60 min;65,70,80℃for 10,15,20 min).Control aliquots were stored at room temperature for 60 *** all aliquots were tested in a real-time fluorescence PCR using primers against *** of inactivation temperature and time,7 of 12 cases(58.3%)tested were positive for SARS-CoV-2 by PCR,and cycle threshold values were *** results suggest that virus inactivation parameters exert minimal infuence on PCR test *** at 65℃for 10 min may be sufficient to ensure safe,reliable testing.

关键词： SARS-CoV-2 COVID-19 throat swabs real-time fluorescence PCR

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Carbendazim sensitivity in populations of Colletotrichum gloeosporioides complex infecting strawberry and yams in Hubei Province of China

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Journal of Integrative Agriculture 2018年第6期17卷 1391-1400页

作者： han Yong-chao ZENG Xiang-guo XlANG Fa-yun ZhanG qing-hua guO Cong CHEN Feng-ying gu Yu-chen Institute of Industrial Crops Hubei Academy of Agricultural SciencesWuhan 430064P.R.China Hubei Key Laboratory of Crop Diseases Insect Pests and Corp Weeds Control/Key Laboratory of Integrated Pest Management on Crops in Central ChinaWuhan 430064P.R.China

The ascomycete fungus Colletotrichum gloeosporioides is a devastating plant pathogen with a wide host range and worldwide distribution. Carbendazim has been widely used to control anthracnose caused by the C. gloeosporioides complex in China for more than 30 years and resistance to carbendazim has been reported in China. A total of 125 Colletotrichum isolates of strawberry and yam were collected from different geographical regions in Hubei Province, China. Approximately 52.8％ of Colletotrichum spp. isolates showed resistance to carbendazim. The isolates tested in this study belong to four species, and the frequencies of resistant isolates differed across Colletotrichum species. Resistant isolates were found in C. siamense and C. fructicola. In contrast, all isolates of C. gloeosporioides and C. aenigma were sensitive to carbendazim. Highly carbendazim-resistant isolates harbored the E198A mutation in the β-tubulin 2 （TUB2） gene, whereas moderately carbendazim-resistant isolates harbored the F200Y mutation in the TUB2 gene. Carbendazim-sensitive Colletotrichum isolates in this study were not genetically similar enough to form a separate cluster from resistant isolates. The result of this study emphasizes the importance of knowing which Colletotrichum sp. is present, when strategies for disease control are made.

关键词： carbendazim resistance frequency Colletotrichum gloeosporioides Colletotrichum species point mutations anthracnose

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Requirements for Evaluation on Drug-medical Device

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Chinese Journal of Biomedical Engineering(English Edition) 2009年第4期18卷 178-184页

作者： deng Jie TIAN Jia-xin gu han-qing Center for Medical Device Evaluation State Food and Drug Administration Beifing 100044 China Tianjin Medical University Tianjin 300070 China

The administration of combination products in *** and Drug Administration(FDA)are analyzed and summarized in this ***,the technical evaluation on drug-medical device in the State Food and Drug Administration of China(SFDA)is also ***,this paper discusses how to promote the development of drug-medical device in the administration and technical evaluation.

关键词： drug-medical device combination products evaluation

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Molecular-Cytological Identification and Chromosome Behavior Analysis of Telotetrasomic in Rice

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Rice science 2008年第3期15卷 161-165页

作者： GONG Zhi-yun GAO qing-song Yu Heng-xiu YI Chuan-deng gu Ming-hong Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Key Laboratory of Plant Functional Genomics Ministry of Education Yangzhou University Yangzhou 225009 China

From the progenies of a telotrisomic of chromosome 9 short arm of an indica rice variety, Zhongxian 3037, a phenotypical variant was selected. The variant plant had rolled leaves, dispersed plant type, as well as a low seed-setting rate. Cytological and molecular cytological investigations revealed two extra chromosomes, which were the shortest in somatic cells of the variant. Fluorescent in situ hybridization （FISH） analysis using a rice centromere specific DNA （RCS2） and a DNA sequence specific for chromosome 9 on premetaphase and pachytene chromosomes showed that these two chromosomes were the short arms of chromosome 9. That is to say, the variant was a telotetrasomic of chromosome 9. Among the 25 pachytene cells, the two telosomic chromosomes paired each other to form a bivalent and didn＇t pair with other normal chromosome 9 as multivalents in 96% cells. However, the bivalent was easy to disassociate in advance.

关键词： rice telotetrasomic meiosis fluorescent in situ hybridization molecular cytology chromosome behavior

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