Graphene meets biology

Graphene features a shining star in the material sciences since its discovery in 2004. Biomedical application of graphene-family materials has been driven recently. In this paper, we overviewed the cutting-edge research in the biomedical application of graphene-based biomaterials, such as bio-sensing and bio-imaging, drug/gene delivery and scaffold for tissue engineering. We emphasized on the effect of graphene substrates on cellular behaviors of adhesion, proliferation~ and differentiation. The develop- ment of three-dimensional scaffolds based on graphene- based nanomaterials and the potential of these constructs in tissue engineering are discussed. The perspectives and challenges are also addressed.     

Novel Chitosan-based Biomaterials

1 Introduction Chitosan with two long side chains of N-alkyl group is an important amphiphilic material, which has potential application in tissue engineering and drug delivery system. In this paper the amphiphilic N, N-dilauryl chitosan has been prepared by the phase transfer catalysis. The π-A isotherms of the products were measured in order to find some fundamental data for making self-assembled vesicles out of this kind of material. The LB film experiment indicates that N, N-dilauryl …     

Micro/nano needles for advanced drug delivery

Along with the boost of drugs’ exploitation, drug delivery has been a common concern among researchers and patients. As an emerging strategy, the micro- and nano-needle (MNN) is a single or an array of micro/nanoneedles, and promises to be a robust technology for efficient, noninvasive and convenient drug delivery. Compared with the conventional injection, MNN can pierce the bio-membranes to transfer cargos without any damage of tissue or nerves. And regarding the topical drug release, MNN is more efficient than oral administration and topical cream. More specifically, microneedle, a powerful technique, has been widely applied in different diseases such as diabetes, anti-obesity and contraception through skin and ocular surface. Correspondingly, many novel microneedles and optimization methods have been developed recently to improve the drug delivery efficacy. Nanoneedle, much smaller than microneedle, can minimize the skin damages caused by the repeated use of microneedles. Nanoneedles with nanoscaled size are usually used to penetrate the cell membrane. And recently many stimulus-aided methods like electrical and magnetic force have been invented to deepen penetration and improve transfer effects. The aim of this review is to introduce the recent advances of MNN-based drug delivery, including their types, application locations and diseases, optimization of delivery strategies and future development prospects.     

Therapy with monoclonal antibodies by elimination of T-cell subsets in vivo

A major aim in immunology has been to understand how the immune system evokes characteristic responses to infection, foreign tissue grafts and tumours. The current view of immunoregulation is based mainly on studies of lymphocyte subsets, either in vitro or by adoptive transfer to irradiated recipients. Many reagents are available for defining T-cell subsets, but only recently have there been helper T-cell-specific antibodies against the mouse equivalent of the Leu3/T4 (man) and W3/25 (rat) antigens. It is clear that monoclonal antibodies will eventually replace antilymphocyte globulin for immunosuppression in organ grafting, but although there has been some clinical success, most monoclonal reagents cause only transient reductions in their target cells in vivo. This uncertainty in the potency of monoclonal antibodies has led some workers to consider them as targeting agents for such highly cytotoxic drugs as ricin A (ref. 21). We show here that unmodified monoclonal antibodies can be extremely effective at depleting cells in vivo and can be used for the selective manipulation of different aspects of the immune response.     

Stimuli-responsive polymeric materials for human health applications

Stimuli-responsive polymers have the extraor- dinary ability to change their physical and/or chemical state after they ＂detect＂ a change in their environment; their response depends dramatically on their chemical compo- sition. This property has been used for a plethora of applications; this review highlights their utility for human health. Specifically, this review will highlight efforts in the areas of sensing and biosensing, antimicrobial/antifouling coatings, tissue engineering and regenerative medicine, and drug delivery. Specific examples are given in each of these areas, with some focus on our work engineering poly（N- isopropylacrylamide）-based microgels and other respon- sive systems.     

两性霉素B合成基因簇及其组合生物学进展

 两性霉素B（AmB）作为第一个用于深部真菌感染的药物,自上市以来已使用超过半个世纪,目前仍是临床治疗中不可缺少的药物。随着近年来AmB衍生物药物的发展,以及其生产菌株结节链霉菌（Streptomyces nodosus）全基因组和AmB体内合成代谢途径的解析,运用基因工程和代谢工程的方法对AmB组合生物合成的研究逐渐增多。由于AmB在当今临床治疗上的地位仍极其重要,因此促进AmB产业的发展具有显著的经济及社会效益。本文对AmB进行了概述,并对其合成基因簇相关基因及其当前组合生物合成的研究现况进行了总结与探讨。     

Microbial production of biopoly esters-poly hydroxyalkanoates

Polyhydroxyalkanoate, abbreviated to PHA, is a family of polyesters produced by a variety of microorganisms. Over 90 PHA with various structure variations have been reported and the number is still increasing. Some interesting physical properties of PHA such as piezoelectricity, nonlinear optical activity and biocompatibility, offer promising applications in areas such as tissue engineering and drug delivery. Worldwide there have been many attempts to produce PHA as biodegradable plastics using various microorganisms obtained from screening natural environments, genetic engineering and mutation methods. It has been found that PHA synthesis is a common phenomenon of bacteria inhabiting in various locations, especially oil-contaminated soils. Bacterial strains capable of synthesizing PHA with various monomers have been identified from oil-contaminated soils, and PHA production strains capable of rapid growth and rapid PHA synthesis on molasses substrate have also been found on molasses contaminated soil. It seems that the combination of novel properties and lower cost will allow easier commercialization of PHA.     

二维功能材料的生物学效应

继石墨烯被发现以来,因其稳定的二维结构和独特的物理化学性质,在材料、能源、环境、生物等领域展现出广泛应用前景,也已成为纳米生物医学的研究热点,被用于生物传感、细胞成像、药物运输、组织工程等领域.随后,具有类似结构的相关二维功能材料的研究也层出不穷、备受关注.本文综述了以石墨烯为代表的二维功能材料的生物学效应,并作出展望.     

组织工程—体外重建人体组织

全部或部分重建皮肤、肝、骨髓、神经等组织一直是基础研究、临床医学和生物工程领域的科学家们所追求的目标，动物细胞与组织体外培养技术的发展使之成为可能。本文主要综述组织工程的研究现状，应用及存在的问题。     

干细胞工程的应用前景研究

近些年来干细胞的应用研究几乎涉及到所有生命科学和生物医学研究领域．由于干细胞能够自我更新和多向分化的生物学特性，使得干细胞工程在细胞的分化和胚胎发育、转基因动物和动物克隆、新型高效药物的开发和临床细胞治疗、组织工程等方面的研究中等有着广泛的应用前景，同时，作为一门新兴学科也面临着许多挑战．     

Carbon nanotubes in biology and medicine: An overview

Rapid development in the field of nanomedicine is bringing novel opportunities for improved disease diagnosis and drug delivery. Among various nanomaterials involved in nanomedicine, carbon nanotubes (CNTs) possessing a unique one-dimensional structure with interesting intrinsic mechanical, physical, and chemical properties have been extensively explored for a wide range of applications in biology and medicine. This review article provides an overview of how CNTs are used in different aspects of biomedicine including drug delivery and cancer treatment, bio-sensing, biomedical imaging, as well as tissue engineering. The recent developments, future perspective, and major challenges in this field are discussed.     

细菌纤维素组织工程支架的仿生矿化研究

骨骼创伤已经成为当今影响人类健康的一大病症。因此,骨修复材料就成为研究的一大热点。骨组织工程支架作为重要的骨修复材料,可以诱导成骨细胞生长并为新骨生长提供条件。传统的骨组织工程支架包括合成高分子(如聚乳酸、聚乙醇酸等)和天然高分子(如胶原、壳聚糖等)。与传统支架材料相比,细菌纤维素(BC)具有良好的生物相容性、精细的纳米空间三维网络结构,有作为组织工程支架的潜能。通过仿生矿化处理,BC纳米纤维表面可以生长出羟基磷灰石(HA)的晶体颗粒,且HA颗粒均匀覆盖在纳米纤维表面。通过热分析得出,仿生矿化处理会使BC的热稳定性得到一定的提升。     

The immunopathogenesis of sepsis

Sepsis is a condition that results from a harmful or damaging host response to infection. Many of the components of the innate immune response that are normally concerned with host defences against infection can, under some circumstances, cause cell and tissue damage and hence multiple organ failure, the clinical hallmark of sepsis. Because of the high mortality of sepsis in the face of standard treatment, many efforts have been made to improve understanding of the dysregulation of the host response in sepsis. As a result, much has been learnt of the basic principles governing bacterial-host interactions, and new opportunities for therapeutic intervention have been revealed.     

设计-建造承包模式在中国的推广应用

近年来,设计-建造承包模式在国际上呈现逐渐增长的趋势;但是,这种承包模式在中国比例较小,与国际的发展趋势不相适应．文中通过文献研究和访谈,在归纳设计-建造模式的特点及日益广泛的应用范围的基础上,从建筑法规、企业结构、人员能力3个方面分析了DB模式在中国发展缓慢的原因．最后,就这3个方面如何在中国建设推广DB模式的环境提出建议,以期提高我国的工程管理水平、增强我国建筑企业的竞争力．     

凝集素的分离纯化、基因克隆及功能研究进展

凝集素(lectin)研究近年来发展迅速，尤其在植物基因工程中，植物外源凝集素基因越来越受到重视。本文从凝集素的分离纯化、基因克隆、理化性质和功能等方面进行了综述。此外还讨论了凝集素基因在植物基因工程中的应用。     

纳米级5-FU变形脂质体的体外透瘢痕试验

为了研究变形脂质体在增生性瘢痕中的渗透作用,制备载抗瘢痕药物5-氟尿嘧啶（5-FU）的纳米级变形脂质体,用荧光剂罗丹明6GO标记,进行体外透皮、透瘢痕试验,通过高效液相色谱分析检测不同作用时间后皮肤和增生性瘢痕的累积药物透过量以及24 h后皮肤和瘢痕组织内的药物滞留量,并采用激光共聚焦显微镜分析荧光强度.各组24 h药物累积透过量由大至小的排序为：5-FU变形脂质体透瘢痕组（T-scar）、5 FU水溶液透瘢痕组（C-scar）、5-FU变形脂质体透皮肤组（T-skin）、5-FU水溶液透皮肤组（C-skin）;24 h后皮肤和瘢痕组织内的药物滞留量以及荧光强度由大至小的排序为：T-scar、T-skin、C-scar、C-skin.结果表明：变形脂质体在增生性瘢痕中的渗透能力最强,对于增生性瘢痕来说,变形脂质体是一种高效的载药渗透材料.     

微载体在组织工程中的应用

微载体是跨越组织工程诸多学科的一个通用工具,它可以作为大量扩增种子细胞的良好载体,也可以作为组织工程中细胞转运传递的支架.微载体培养技术作为一种新兴的大规模细胞培养技术,在组织工程学中主要应用于种子细胞的扩增培养.目前,利用微载体进行组织工程细胞的大规模培养受到生物、医学科研人员的青睐.     

Cellulose Nanocrystals-Coated Polylactide(PLA) Microspheres Obtained via a Pickering Emulsion Approach

In order to prepare cellulose nanocrystals( CNCs)-coated polylactide( PLA) microspheres for the use of drug delivery and tissue engineering,a Pickering emulsion route was applied. The stable Pickering emulsions were prepared using CNCs as efficient stabilizers without any additional surfactant. The microspheres were successfully fabricated after volatilization of the solvent. What's more,the size of microspheres could be controlled by fabrication parameters.     

Glycoprotein C of herpes simplex virus 1 acts as a receptor for the C3b complement component on infected cells

Receptors for the Fc portion of immunoglobulins or for the third component of complement (C3) are present on a variety of circulating and fixed tissue cells including granulocytes, monocytes, lymphocytes and glomerular epithelial cells. Cells which lack Fc receptors may express them after infection by herpes simplex virus (HSV)-1, HSV-2, cytomegalovirus or varicella zoster virus. We recently reported that infection by HSV-1 induces both Fc and C3 receptors on human endothelial cells. Glycoprotein E of HSV-1 has been shown to function as an Fc receptor. We now demonstrate that glycoprotein C (gC) of HSV-1 functions as a C3b receptor. This receptor appears following HSV-1, but not HSV-2, infection. Detection of the C3b receptor is blocked by monoclonal antibodies to glycoprotein C (gC) of HSV-1, but not by monoclonal antibodies to other HSV-1 glycoproteins. In addition, the MP mutant of HSV-1, which lacks gC, fails to express a C3b receptor. These results assign a new function of gC of HSV-1 and demonstrate potentially important differences between HSV-1 and HSV-2 glycoproteins.     

HIV感染的治疗性DNA疫苗（综述）

DNA疫苗被称为继完速病原体疫苗和基因工程重组蛋白疫苗后的第3代疫苗,其兼有重组亚单位疫苗的安全性和减毒活疫苗的有效性。HIV感染的防治则以激发细胞免疫为主,以激发细胞免疫为主的DNA疫苗给HIV感染防治带来曙光。目前DNA疫苗在HIV感染防治研究方面已取得显著进展,其临床研究已证明具有明显的刺激机体细胞免疫的效果,尤其是一些细胞因子、趋化因子可明显增强HIV DNA疫苗的免疫反应。就DNA免疫佐剂、HIV病毒基因DNA疫苗作用机制以及加强HIV DNA疫苗的各种调节因素方面的研究进展进行综述,以促进HIV DNA疫苗防治的研究。