中枢神经再生材料研究进展

首先介绍了目前中枢神经再生面临的问题和应对策略,然后系统地综述了脑再生和脊髓再生修复材料的发展。研究发现,成人中枢神经系统内存的神经干细胞和具有特定分化方向的前体细胞具有潜在的、巨大的修复功能;生物支架材料与神经干细胞的联合使用能够较好地控制细胞微环境,有望提高细胞移植后的存活状况,促进中枢神经再生。最后,结合现在中枢神经再生的研究热点——神经干细胞,阐述了中枢神经再生材料调控干细胞的研究进展和潜能,为联合应用生物材料与干细胞促进中枢再生提供了参考。     

锶锌共掺杂磷酸八钙微球制备及其骨修复性能

本文研究了锶、锌共掺杂磷酸八钙多孔微球(Sr/Zn-OCP)的制备及其体内成骨生物学效应。实验运用湿化学合成工艺制备了粒径为105μm、280μm和500μm三种单分散微球颗粒材料,然后再考察微球材料对大白兔股骨缺血性坏死骨缺损的再生修复效应以及微球颗粒度对缺损修复效率的影响规律,运用理化表征与组织学分析考察了微球的微结构和骨组织修复特性。结果显示,利用低浓度聚丙烯酸可以诱导多层化尺度均一的Sr/Zn-OCP多孔微球颗粒形成,并且通过改变反应溶液的搅拌速率可以改变微球的尺度大小;同时,三种粒度微球堆积体均可见骨缺损内新骨再生,但是粒度最大的500μm微球修复骨缺损效率最高,在微球植入术后10、16周时新骨再生率达到37%和62%。以上研究结果表明多孔性Sr/Zn-OCP微球具有优良的生物活性效应,在解决病理性骨缺损再生修复方面具有良好应用价值。     

骨修复用生物玻璃复合材料研究进展

生物玻璃是一类性能优良的生物材料,具有良好的生物活性和生物相容性,作为骨修复植入体可以在材料界面与人体骨组织之间形成化学键合,诱导骨的修复与再生.将生物玻璃与其它材料进行复合,可以制备出生物活性和机械性能优良的骨修复复合材料.综述了生物玻璃复合材料的研究现状,并探讨了该类材料目前存在的不足,展望了其发展趋势.     

人工软骨支架材料、结构设计与制备技术研究进展

骨软骨是一种半透明状组织,主要功能是传递、吸收应力和减少摩擦。由于结构和功能复杂性,软骨一旦受损很难修复和再生,软骨缺损治疗仍是一大临床难题。随着再生医学蓬勃发展,组织工程人工软骨技术有望在软骨修复和治疗领域发挥重要作用。首先介绍了天然关节软骨不同分层的解剖结构和功能特征,然后重点从人工软骨支架构建材料、结构设计和制备技术等方面系统地综述了人工软骨组织工程技术的最新进展,最后讨论了人工软骨支架当前面临主要问题和未来发展方向,以期为相关研究提供参考。     

我国生物医用材料产业期待爆发

正生物医用材料是指用于诊疗、修复、替换人体器官或增进组织功能的高科技材料。快速发展、安全有效的生物医用材料在提高人们生活质量、保障人类健康方面扮演着重要角色,与人类的健康息息相关,已逐渐成为快速发展的新兴产业。研究生物医用材料的最终目的是用其能够代替或修复人体器官,并最终实现其生理功能。其前沿领域的应用主要集中表现在:具有诱导组织再生生物功能的新型医用     

体表创面修复材料的研究进展

创面修复材料对人体皮肤各种损伤的痊愈尤为重要,一直是临床研究的重要课题.介绍了3个发展阶段划分的新观点,即传统敷料、生物敷料及复合型敷料和组织工程化皮肤,并指出了各阶段存在的问题.其中组织工程原理为研究创面修复材料提供了广阔的前景,目前的研究工作多基于此理论,最后总结了今后的研发方向.     

胶原基复合型组织工程化皮肤制备中的关键科学技术问题

胶原基复合型组织工程化皮肤是未来发展的方向和研究热点。本文在介绍组织工程化皮肤的基础上,简要地综述和探讨了胶原改性的原理与方法、胶原基复合支架材料的造孔方法及其与孔结构之间的关系、种子细胞的选择、细胞与支架材料的复合培养、血管化及其影响因素、及其它皮肤附属器官的再生等关键科学技术问题,并阐明了解决这些科学技术问题的思路和方法,为组织工程化皮肤的研发提供了有益的借鉴。     

聚d,l-乳酸及其对20 毫米断缺神经诱导修复的研究

报道了聚－d,l-乳酸在大鼠体内的降解，以及用聚d,l-乳酸制备的神经诱导管对大鼠坐骨神经20mm断缺修复的研究，通过肉眼观察，组织学检查，电镜观察，以及电生理测定等方法和手段，对神经诱导再生过程进行了跟踪，揭示了随着神经的再生聚d,l-乳酸管形态的变化，且对神经修复的效果进行了评价，研究表明：用聚d,l-乳酸管可成功地诱导20m断缺神经得到再生修复。     

原位聚合法制备微胶囊的研究进展

微胶囊由于优良的性能而受到研究者的广泛关注,常用的制备方法有界面聚合法和原位聚合法等。其中原位聚合法是一种重要的微胶囊制备方法,具有成本低、适合工业化生产等优点。主要介绍了原位聚合法制备微胶囊的原理,以及制备过程中壁材原料、乳化剂、乳化速度等相关因素对制备效果的影响,重点阐述了近年来原位聚合法在制备相变材料微胶囊、阻燃剂微胶囊和自修复材料微胶囊等方面的研究现状。最后指出了原位聚合法在制备微胶囊研究中存在的问题,也对该领域未来的研究方向提出了建议。     

硬组织修复材料的骨再生机理研究

传统硬组织修复材料由于在组成及结构上与人体骨组织存在较大差异,植入体内后的骨组织修复过程基本上是一种被动的"充填"过程,且材料的降解速度与新骨形成速度不匹配,难以达到真正的"生物性融合",严重制约了该类材料在骨科临床的推广应用。因此,设计与制备具有"主动修复功能"和"可调控生物响应特性"的第3代新型硬组织修复材料已成为当前骨科临床的新需求和未来的发展方向。介绍了硬组织修复材料的骨再生机理研究方法,综述了硬组织修复材料与宿主防御和骨再生及宿主微环境对材料与宿主细胞相互作用的研究现状。指出硬组织修复材料植入体内后所发生的序列事件可能通过表观遗传修饰使得基因表达受材料本身和宿主微环境等因素的调控,提出新型硬组织修复材料研究中存在的问题和发展趋势。     

A review of tissue-engineered skin bioconstructs available for skin reconstruction

Situations where normal autografts cannot be used to replace damaged skin often lead to a greater risk of mortality, prolonged hospital stay and increased expenditure for the National Health Service. There is a substantial need for tissue-engineered skin bioconstructs and research is active in this field. Significant progress has been made over the years in the development and clinical use of bioengineered components of the various skin layers. Off-the-shelf availability of such constructs, or production of sufficient quantities of biological materials to aid rapid wound closure, are often the only means to help patients with major skin loss. The aim of this review is to describe those materials already commercially available for clinical use as well as to give a short insight to those under development. It seeks to provide skin scientists/tissue engineers with the information required to not only develop in vitro models of skin, but to move closer to achieving the ultimate goal of an off-the-shelf, complete full-thickness skin replacement.     

电子皮肤热点核心材料及其在生命健康领域中的应用研究进展

人体皮肤能够感知外界的信息,在与外界交流中起着重要的作用。模仿人体皮肤特性和环境感知能力的电子皮肤在医疗监控、仿生假肢与机器人触觉感知等领域中有着广泛的应用。与传统的可穿戴传感器相比,电子皮肤更轻、更灵活、更具延展性,而且具有无线、透明、与人体皮肤兼容等特性,已成为新兴的研究领域之一。电子皮肤可以连续检测人体的大量物理和生化参数、人体运动、气体等,以实时监测人体健康、体育运动以及各种环境中的气体。本文综述了电子皮肤所使用的最新材料,包括零维（0D）、一维（1D）、二维（2D）和三维（3D）微纳米材料、聚合物材料、水凝胶材料及其复合材料等;详细归纳了基于这些热点核心材料所构建的电子皮肤在健康监测、运动监测以及气体监测等生命健康领域中的应用;指出了电子皮肤在研究过程中依然存在着成本高、工艺复杂等技术难题,但电子皮肤发展趋势朝着多功能化和多种外界刺激同步检测发展,并且在医疗设备、机器技术及未来的制造领域中应用前景广阔。     

Measurement of Thermal Effusivity of Human Skin Using the Photoacoustic Method

In order to understand heat transfer in the human body, information regarding the thermophysical properties of biological materials is required. It is preferable that these properties are evaluated by in vivo measurements. The photoacoustic method is a non-contact, non-destructive method of measuring the thermophysical properties of various materials. In this study, the photoacoustic method was applied to human skin, and an open-type cell for on-site measurements was used instead of the previously used closed-type cell. Measurements of the thermophysical properties of human skin were carried out, and reasonable values of the thermal effusivity of the skin were obtained. Differences between different body parts and individual variations in thermal effusivity were investigated.     

Tough and Water‐Insensitive Self‐Healing Elastomer for Robust Electronic Skin

An electronic (e‐) skin is expected to experience significant wear and tear over time. Therefore, self‐healing stretchable materials that are simultaneously soft and with high fracture energy, that is high tolerance of damage or small cracks without propagating, are essential requirements for the realization of robust e‐skin. However, previously reported elastomers and especially self‐healing polymers are mostly viscoelastic and lack high mechanical toughness. Here, a new class of polymeric material crosslinked through rationally designed multistrength hydrogen bonding interactions is reported. The resultant supramolecular network in polymer film realizes exceptional mechanical properties such as notch‐insensitive high stretchability (1200%), high toughness of 12 000 J m^?2, and autonomous self‐healing even in artificial sweat. The tough self‐healing materials enable the wafer‐scale fabrication of robust and stretchable self‐healing e‐skin devices, which will provide new directions for future soft robotics and skin prosthetics.     

用于构建可溶性微针的基质材料及其复合材料

可溶性微针作为新型透皮给药制剂,打破了传统皮肤给药制剂不能用于大分子药物经皮给药的局限,且具有无痛、无创、无出血、卫生、生物相容性好、便于患者自主使用等诸多优点。近年来可溶性微针的研究已成为备受关注的热点。基质材料的选择直接影响微针的制备及皮肤刺入、药物释放等性能。介绍了可溶性微针的研究现状,对基质材料进行了分类与介绍,并综述了基质材料的复合使用及效果。同时介绍了韧性材料和脆性材料的特性及其复合后的协同效果,进而对该领域存在的问题和研究方向进行了讨论和展望。     

Optimum discretization of a physical Cauer circuit

A physical Cauer circuit is used to model skin effect in a conductor or eddy currents in a magnetic lamination. A physical lumped element model was chosen, because equivalent circuits are inconvenient for nonlinear materials such as magnetic materials. Approaches to discretize the used circuit are presented and compared. An iterative fitting technique is suggested that requires fewer elements and yields higher accuracy than an exponential discretization.     

A Simplified Model to Determine the Contribution of Strain Energy in the Failure Process of Thin Biological Membranes during Cutting

Abstract:  Thin biological membranes such as skin are highly deformable, nonlinear in behaviour and fracture resistant. As a result of these properties, measuring the resistance to fracture of such materials is difficult. This paper investigates the resistance to fracture of a thin biological membrane, using the example of animal skin. Models of cutting using a fracture approach are examined and a review of the structure and mechanical properties of skin is given. A review of previous work in examining the fracture behaviour of skin is carried out and a strain energy-based failure model for skin is proposed. A method of measuring the fracture resistance of skin in opening mode (mode I) using this failure model is described. Values for the resistance to fracture of skin samples were calculated from experiments to be 2.32 ± 0.40 kJ m⁻². These results were found to be in good agreement with the literature. The model and experimental technique proposed here may be applied to establish the failure properties of membranes and, in particular, a range of soft tissues under a variety of cutting conditions.     

Hydrogel Microneedle Arrays for Transdermal Drug Delivery

Nano-Micro Letters - Stratum corneum is the main obstacle for drugs to pass through the skin. Microneedles are composed of arrays of micro-projections formed with different materials, generally...     

Biomolecular Piezoelectric Materials: From Amino Acids to Living Tissues

Biomolecular piezoelectric materials are considered a strong candidate material for biomedical applications due to their robust piezoelectricity, biocompatibility, and low dielectric property. The electric field has been found to affect tissue development and regeneration, and the piezoelectric properties of biological materials in the human body are known to provide electric fields by pressure. Therefore, great attention has been paid to the understanding of piezoelectricity in biological tissues and its building blocks. The aim herein is to describe the principle of piezoelectricity in biological materials from the very basic building blocks (i.e., amino acids, peptides, proteins, etc.) to highly organized tissues (i.e., bones, skin, etc.). Research progress on the piezoelectricity within various biological materials is summarized, including amino acids, peptides, proteins, and tissues. The mechanisms and origin of piezoelectricity within various biological materials are also covered.     

Electronic Skin: Recent Progress and Future Prospects for Skin‐Attachable Devices for Health Monitoring,Robotics, and Prosthetics

Recent progress in electronic skin or e‐skin research is broadly reviewed, focusing on technologies needed in three main applications: skin‐attachable electronics, robotics, and prosthetics. First, since e‐skin will be exposed to prolonged stresses of various kinds and needs to be conformally adhered to irregularly shaped surfaces, materials with intrinsic stretchability and self‐healing properties are of great importance. Second, tactile sensing capability such as the detection of pressure, strain, slip, force vector, and temperature are important for health monitoring in skin attachable devices, and to enable object manipulation and detection of surrounding environment for robotics and prosthetics. For skin attachable devices, chemical and electrophysiological sensing and wireless signal communication are of high significance to fully gauge the state of health of users and to ensure user comfort. For robotics and prosthetics, large‐area integration on 3D surfaces in a facile and scalable manner is critical. Furthermore, new signal processing strategies using neuromorphic devices are needed to efficiently process tactile information in a parallel and low power manner. For prosthetics, neural interfacing electrodes are of high importance. These topics are discussed, focusing on progress, current challenges, and future prospects.