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Cupric ion release and cytotoxicity for Yuangong Cu-IUDs and the release behavior of indomethacin for medicated 220 Cu-IUD

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Chinese Science Bulletin 2009年第18期54卷 3160-3166页

作者： CAO BianMei XI TingFei zheng yudong YANG LiFeng zheng Qi School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China National Institute for the Control of Pharmaceutical & Biological Products Beijing 100050 China Shenzhen Institute of Peking University Shenzhen 518057 China Wenzhou Medical College Wenzhou 325035 China

These years Yuangong copper-bearing intrauterine devices (Cu-IUDs) have been used because of less side effects in use. The corrosion of copper is essential to the success of contraception, and the release behavior of indomethacin from medicated Cu-IUD is related to its therapeutic effect. In this study, analytical methods were established to investigate the release behavior of cupric ion of three kinds of Yuangong Cu-IUDs and indomethacin of medicated Yuangong 220 Cu-IUD. Cu-IUDs were incubated in simulated uterine solution (SUS). The concentrations of cupric ion and indomethacin were analyzed by flame atomic absorption spectrometer (FAAS) for 60 days and UV/vis ?3310 spectrophotometer for 60 days, respectively. The morphology of copper after corrosion was characterized by SEM. In addition, we detected cytotoxicity by MTT of L929 mouse fibroblasts cells caused by extracts of the three Yuangong Cu-IUDs. The release behavior of cupric ion for three kinds of Yuangong Cu-IUDs was biphasic, which consisted of the initial burst release and then slow and constant release. In vitro release experiment confirmed a biphasic release of indomethacin from Yuangong 220. The copper wire of Yuangong Cu-IUDs showed uneven corrosion. The RGR value of Yuangong 365 Cu-IUD was smaller than that of medicated Yuangong 220 Cu-IUD and RGR value of medicated Yuangong 220 Cu-IUD was smaller than that of Yuangong 300 Cu-IUD. The cupric ion release and indomethacin release showed biphasic. Indomethacin increased the cupric ion release rate and might diminish the adverse effects caused by burst release of cupric ion. The toxicity grade of these three Yuangong Cu-IUDs was 4. We should canvass the adverse events of Cu-IUDs based on practical experiments, and try our best to reduce the toxicity of Cu-IUDs.

关键词：宫内节育器铜离子释放行为吲哚美辛细胞毒性避孕

Multifunctional MgF_2/Polydopamine Coating on Mg Alloy for Vascular Stent Application

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Journal of Materials Science & Technology 2015年第7期31卷 733-743页

作者： Xiaoli Liu Zhen Zhen Jing Liu Tingfei Xi yudong zheng Shaokang Guan Yufeng zheng Yan Cheng School of Materials Science and Technology University of Science and Technology Beijing Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking University Shenzhen Research Institute Peking University Materials Research Center School of Materials Science and EngineeringZhengzhou University

Mg alloy is of great potential in the application of vascular stent due to its degradation in physical environment and proper mechanical property. However its mechanical integrity does not meet the clinical requirement clue to relatively fast degradation. Besides, in order to accelerate the re- endothelialization of Mg-based stents, it needs surface modification to improve the attachment, growth and adhesion of endothelial cells （ECs）. To solve the main obstacles, an anti-corrosion and quick endothelialization coating was prepared on novel Mg-Zn-Y-Ncl alloy via a simple two-step immersion method in the present study, first in hydrofluoric acid （HF） then in dopamine tris-Hydrochloric acid （tris -HCI） solution. The coating was uniform and thin, which consisted of two layers--the upper was pol- yclopamine （PDA） layer and the lower was MgF2 layer. The alloy with the coating demonstrated dramatic corrosion resistance enhancement in vitro by immersion test and electrochemical test. Moreover the HF- PDA-treated Mg alloy exhibited great performance of cell adhesion and proliferation. The coating created a favorable environment for ECs to have a competitive advantage over vascular smooth muscle ceils （VSMCs）, which was preferable for re-enclothelialization. The results suggest that HF-PDA-treatecl Mg -Zn-Y-Nd alloy has great potential in the application of vascular stent and the surface coating method is of great aPPlication value in biodegraclable Mg alloy stent clue to its simplicity and effectiveness.

关键词： Mg-Zn-Y-Nd alloyVascular stentHF converted layerPolydopamineCorrosion resistanceRe-endotheliazation

Non-negligible factors in low-pressure sprinkler irrigation:droplet impact angle and shear stress

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Journal of Arid Land 2022年第11期14卷 1293-1316页

作者： HUI Xin zheng yudong MUHAMMAD Rizwan Shoukat TAN Haibin YAN Haijun College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Engineering Research Center of Agricultural Water-Saving and Water Resources Ministry of EducationBeijing 100083China Semi-arid Agriculture Engineering&Technology Research Center of China Shijiazhuang 050051China

Droplet shear stress is considered as an important indicator that reflects soil erosion in sprinkler irrigation more accurately than kinetic energy,and the effect of droplet impact angle on the shear stress cannot be *** this study,radial distribution of droplet impact angles,velocities,and shear stresses were investigated using a two-dimensional video disdrometer with three types of low-pressure sprinkler(Nelson D3000,R3000,and Komet KPT)under two operating pressures(103 and 138 kPa)and three nozzle diameters(3.97,5.95,and 7.94 mm).Furthermore,the relationships among these characteristical parameters of droplet were analyzed,and their influencing factors were comprehensively *** various types of sprinkler,operating pressures,and nozzle diameters,the smaller impact angles and larger velocities of droplets were found to occur closer to the sprinkler,resulting in relatively low droplet shear *** increase in distance from the sprinkler caused the droplet impact angle to decrease and velocity to increase,which contributed to a significant increase in the shear stress that reached the peak value at the end of the ***,the end of the jet was the most prone to soil erosion in the radial direction,and the soil erosion in sprinkler irrigation could not only be attributed to the droplet kinetic energy,but also needed to be combined with the analysis of its shear *** comparing the radial distributions of average droplet shear stresses among the three types of sprinklers,D3000 exhibited the largest value(26.94-3313.51 N/m^(2)),followed by R3000(33.34-2650.80 N/m^(2)),and KPT(16.15-2485.69 N/m^(2)).From the perspective of minimizing the risk of soil erosion,KPT sprinkler was more suitable for low-pressure sprinkler irrigation than D3000 and R3000 *** addition to selecting the appropriate sprinkler type to reduce the droplet shear stress,a suitable sprinkler spacing could also provide acceptable results,because the distance

关键词： center pivot irrigation system water droplet universal model soil erosion water-saving irrigation

Regulatory science for hernia mesh: Current status and future perspectives

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Bioactive Materials 2021年第2期6卷 420-432页

作者： Wenbo Liu Yajie Xie yudong zheng Wei He Kun Qiao Haoye Meng School of Material Science and Engineering University of Science and Technology Beijing30 Xueyuan RoadHaidian DistrictBeijingChina Center for Medical Device Evaluation National Medical Products AdministrationIntellectual Property Publishing House MansionQixiang RoadHaidian DistrictBeijingChina

Regulatory science for medical devices aims to develop new tools,standards and approaches to assess the safety,effectiveness,quality and performance of medical *** the field of biomaterials,hernia mesh is a class of implants that have been successfully translated to clinical *** a focus on hernia mesh and its regulatory science system,this paper collected and reviewed information on hernia mesh products and biomaterials in both Chinese and American *** current development of regulatory science for hernia mesh,including its regulations,standards,guidance documents and classification,and the scientific evaluation of its safety and effectiveness was first *** the research prospect of regulatory science for hernia mesh was *** methods for the preclinical animal study and new tools for the evaluation of the safety and effectiveness of hernia mesh,such as computational modeling,big data platform and evidence-based research,were *** taking the regulatory science of hernia mesh as a case study,this review provided a research basis for developing a regulatory science system of implantable medical devices,furthering the systematic evaluation of the safety and effectiveness of medical devices for better regulatory *** was the first article reviewing the regulatory science of hernia mesh and biomaterial-based *** also proposed and explained the concepts of evidence-based regulatory science and technical review for the first time.

关键词： Regulatory science Safety and effectiveness Hernia mesh Regeneration Remolding

In vitro and in vivo investigation of bacterial cellulose dressing containing uniform silver sulfadiazine nanoparticles for burn wound healing

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Progress in Natural Science:Materials International 2015年第3期25卷 197-203页

作者： Xiaoxiao Wen yudong zheng Jian Wu Lina Yue Cai Wang Jiabin Luan Zhigu Wu Kaisheng Wang School of Materials Science and Engineering University of Science and Technology Beijing Suzhou Institute of Nano-Tech and Nano-biobics Chinese Academy of Sciences Hospital Affiliated to Chinese PLA General Hospital

Silver sulfadiazine(SSD) particles in homogeneous dispersion state were prepared by an ultrasonic method and then nano- and microparticles were separated using centrifugation. SSD particles with narrow size distribution were impregnated with bacterial cellulose(BC) to produce BC–SSD composite membrane used as burn wound dressing. A scanning electron microscope(SEM) was used to examine the surface morphology of BC–SSD membranes. The incorporation of SSD in BC–SSD was confirmed by X-ray diffraction(XRD). Antimicrobial tests in vitro indicated that BC–SSD showed excellent antibacterial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The effects of BC–SSD on burn wound healing were assessed by rat models. The comparative study confirmed that the wound treated with BC–SSD showed high healing rate. The bacteria count in BC–SSD group was far less than control group. Histological analysis showed that epithelialization progressed better in wound treated with BC–SSD. These values demonstrated that the BC–SSD composite membrane could be a promising wound dressing for burn.

关键词： Bacterial cellulose Silver sulfadiazine Antibacterial activity Burn wound healing

Design and characterization of plasticized bacterial cellulose/waterborne polyurethane composite with antibacterial function for nasal stenting

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Regenerative Biomaterials 2020年第6期7卷 597-608页

作者： Zhaoxuan Feng Minglu Li Xing Jin yudong zheng Junxiu Liu Liang Zhao Yansen Wang Hao Li Danlin Zuo School of Material Science and Engineering University of Science and Technology BeijingBeijingChina Department of Otorhinolaryngology Peking University Third HospitalBeijingChina Research Center for Bioengineering and Sensing Technology University of Science and Technology BeijingBeijing 100083China School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083China

A nasal stent capable of preventing adhesions and inflammation is of great value in treating nasal *** order to solve the problems of tissue adhesion and inflammation response,we prepared plasticized bacterial cellulose(BCG)and waterborne polyurethane(WPU)composite with antibacterial function used as a novel nasal *** gelation behavior of BCG could contribute to protecting the paranasal sinus mucosa;meanwhile,the WPU with improved mechanical property was aimed at supporting the narrow nasal *** thickness,size and the supporting force of the nasal stent could be adjusted according to the specific conditions of the *** analysis,contact angle and water absorption test were applied to investigate the thermal,hydrophilic and water absorption properties of the composite *** composite materials loaded with poly(hexamethylene biguanide)hydrochloride maintained well antibacterial activity over *** experiments further revealed that the mucosal epithelium mucosae damage of BCG-WPU composite was minor compared with that of *** new type of drug-loaded nasal stent can effectively address the postoperative adhesions and infections while ensuring the health of nasal mucosal,and thus has an immense clinical application prospects in treating nasal diseases.

关键词： bacterial cellulose polyurethane biocompatibility nasal stent

A self-crosslinking,double-functional group modified bacterial cellulose gel used for antibacterial and healing of infected wound

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Bioactive Materials 2022年第11期7卷 248-260页

作者： Yajie Xie Kun Qiao Lina Yue Tao Tang yudong zheng Shihui Zhu Huiyi Yang Ziyuan Fang School of Material Science and Engineering University of Science and Technology BeijingBeijingChina Hebei Key Laboratory of Hazardous Chemicals Safety and Control Technology School of Chemical and Environmental EngineeringNorth China Institute of Science and TechnologyLangfang065201HebeiChina Department of Burn Surgery The First Affiliated Hospital of Naval Medical UniversityShanghai200433China

Cellulose/chitosan composite,as a mature commercial antibacterial dressing,is an important type of wound repair ***,how to achieve the perfect compound of two components and improve antibacterial activity is a major,lingering *** this study,a bifunctional group modified bacterial cellulose(DCBC)was prepared by carboxymethylation and selective ***,the chitosan(CS)was compounded in the network of DCBC by self-crosslinking to form dialdehyde carboxymethyl bacterial cellulose/chitosan composites(S-DCBC/CS).The aldehyde group can react with amino of CS by Schiff base *** carboxyl group of DCBC and the amorphous distribution of CS molecular chains increase the antimicrobial properties of *** bacteriostatic rate of composites could be higher than 95%.Bacteria can be attracted onto the surface of composites,what we call it“directional adhesion antibacterial effects”.In particular,a kind of large animal wound model,deep II degree infected scald of Bama miniature pig,was used to research the antimicrobial and healing properties of *** S-DCBC/CS can effectively inhibit bacterial proliferation of wound and kill the *** wound healing rate of S-DCBC/CS was up to 80%after three *** composites show better antibacterial and promoting concrescence effects than traditional chitosan dressings.

关键词： Self-crosslinking Bacterial cellulose Cell migration Wound healing Antimicrobial properties

功能化细菌纤维素纳米晶复合聚氨酯医用抗菌涂层的制备及性能研究

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纤维素科学与技术 2024年第1期32卷 28-38,I0001页

作者：杨惠仪张栗杨丁蒙贺玮谢亚杰乔堃郑裕东北京科技大学材料科学与工程学院北京100083 北京中杰瑞康科技有限公司北京100094

植入医疗器械的感染是临床治疗的难题之一,因此研究具有长效稳定抗菌效果的医用涂层对于医疗植入器械领域十分重要。本研究使用细菌纤维素膜片,通过粉碎―氧化法制备氧化改性细菌纤维素纳米晶体,并化学接枝阳离子化合物双胍制备获得新... 详细信息

植入医疗器械的感染是临床治疗的难题之一,因此研究具有长效稳定抗菌效果的医用涂层对于医疗植入器械领域十分重要。本研究使用细菌纤维素膜片,通过粉碎―氧化法制备氧化改性细菌纤维素纳米晶体,并化学接枝阳离子化合物双胍制备获得新型纳米抗菌材料NBC-BG,最后与聚氨酯(PU)进行复合制备了PU-NBC-BG医用抗菌涂层。通过多种材料表征手段,研究了不同比例添加下涂层的结构性能变化,同时通过抗菌实验证明了PU-NBC-BG涂层具有优良且稳定的抗菌性能以及抗生物膜效果,在医疗器械领域具有很好的前景。

关键词：细菌纤维素纳米晶双胍长效抗菌医用涂层

Cellulose fibers-reinforced self-expanding porous composite with multiple hemostatic efficacy and shape adaptability for uncontrollable massive hemorrhage treatment

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Bioactive Materials 2021年第7期6卷 2089-2104页

作者： Yansen Wang Yifan Zhao Longxue Qiao Faxing Zou Yajie Xie yudong zheng Yong Chao Ying Yang Wei He Siming Yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083PR China Department of Anesthesiology Medical College of Chinese PLABeijing100853PR China Department of Medical Engineering The First Affiliated Hospital of the PLA General HospitalBeijing100048PR China First Affiliated Hospital of Medical College Zhejiang UniversityHangzhou310003PR China Key Laboratory of Wound Repair and Regeneration of PLA Chinese PLA General HospitalMedical College of PLABeijing100853PR China

Uncontrollable hemorrhage leads to high mortality and thus effective bleeding control becomes increasingly important in the military field and civilian trauma ***,current hemostats not only present limitation when treating major bleeding,but also have various side *** we report a self-expanding porous composites(CMCP)based on novel carboxymethyl cellulose(CMC)fibers and acetalized polyvinyl alcohol(PVA)for lethal hemorrhage *** CMC fibers with uniform fibrous structure,high liquid absorption and procoagulant ability,are evenly interspersed inside the composite *** obtained composites possess unique fiber-porous network,excellent absorption capacity,fast liquid-triggered self-expanding ability and robust fatigue resistance,and their physicochemical performance can be fine-tuned through varying the CMC *** vitro tests show that the porous composite exhibits strong blood clotting ability,high adhesion to blood cells and protein,and the ability to activate platelet and the coagulation *** vivo hemostatic evaluation further confirms that the CMCP presents high hemostatic efficacy and multiple hemostatic effects in swine femoral artery major hemorrhage ***,the CMCP will not fall off from the injury site,and is also easy to surgically remove from the wound cavity after the ***,results of CT tomography and 3D reconstruction indicate that CMCP can achieve shape adaptation to the surrounding tissues and the wound cavities with different depths and shapes,to accelerate hemostasis while protecting wound tissue and preventing infection.

关键词： Porous materials Cellulose fibers Self-expanding ability Shape-adaptive Hemostasis