重组蛛丝蛋白支架材料在大鼠体内的组织相容性

目的 探讨基因重组蛛丝蛋白等4种支架材料在大鼠体内的组织相容性.方法 按照生物材料生物学评价试验国家标准进行4种材料的动物体内植入实验,通过大体观察和组织学方法对4种材料进行检测评价.结果 4种材料组织相容性优良顺序为pNSR16、pNS2、PVA、pNSR-Z.pNSR16和pNS2支架材料均显示出良好的组织相容性.结论 重组蛛丝蛋白有良好的组织相容性,其应用于组织工程的前景是广阔的.     

重组蛛丝蛋白支架材料在大鼠体内的组织相容性

目的探讨基因重组蛛丝蛋白等4种支架材料在大鼠体内的组织相容性。方法按照生物材料生物学评价试验国家标准进行4种材料的动物体内植入实验,通过大体观察和组织学方法对4种材料进行检测评价。结果4种材料组织相容性优良顺序为pNSR16、pNS2、PVA、pNSR-Z。pNSR16和pNS2支架材料均显示出良好的组织相容性。结论重组蛛丝蛋白有良好的组织相容性,其应用于组织工程的前景是广阔的。     

Eggshell membrane biomaterial as a platform for applications in materials science

Eggshell membrane (ESM) is a unique biomaterial, which is generally considered as waste. However, it has extraordinary properties which can be utilized in various fields and its potential applications are therefore now being widely studied. The first part of this review focuses on the chemical composition and morphology of ESM. The main areas of ESM application are discussed in the second part. These applications include its utilization as a biotemplate for the synthesis of nanoparticles; as a sorbent of heavy metals, organics, dyes, sulfonates and fluorides; as the main component of biosensors; in medicine; and various other applications. For each area of interest, a detailed literature survey is given.     

Oriented nanofibrous silk as a natural scaffold for ocular epithelial regeneration

The aim of this study was to develop nanofibrous silk substrates for limbal stem cell expansion that can serve as a potential alternative substrate to replace human amniotic membrane. The human limbal stem cell was used to evaluate the biocompatibility of substrates (random and oriented nanofibrous mats, and human amniotic membrane) based on their phenotypic profile, viability, proliferation, and attachment ability. Biocompatibility results indicated that all substrates were highly biocompatible, as limbal stem cells could favorably attach and proliferate on the nanofibrous surfaces. Microscopic figures showed that the human limbal stem cells were firmly anchored to the substrates and were able to retain a normal corneal stem cell phenotype. Microscopic analyses illustrated that cells infiltrated the nanofibers and successfully formed a three-dimensional corneal epithelium, which was viable for 15 days. Immunocytochemistry and real-time PCR results revealed no change in the expression profile of limbal stem cells grown on nanofibrous substrates when compared to those grown on human amniotic membrane. In addition, electrospun nanofibrous silk substrates especially oriented mat provides not only a milieu supporting limbal stem cells expansion, but also serve as a useful alternative carrier for ocular surface tissue engineering and could be used as an alternative substrate to amniotic membrane.     

Regenerated silk fibroin scaffold and infrapatellar adipose stromal vascular fraction as feeder-layer: a new product for cartilage advanced therapy

Articular cartilage has limited repair and regeneration potential, and the scarcity of treatment modalities has motivated attempts to engineer cartilage tissue constructs. The use of chondrocytes in cartilage tissue engineering has been restricted by the limited availability of these cells, their intrinsic tendency to lose their phenotype during the expansion, as well as the difficulties during the first cell adhesion to the scaffold. Aim of this work was to evaluate the intra-articular adipose stromal vascular fraction attachment on silk fibroin scaffold to promote chondrocytes adhesion and proliferation. Physicochemical characterization has demonstrated that three-dimensionally organized silk fibroin scaffold is an ideal biopolymer for cartilage tissue engineering; it allows cell attachment, scaffold colonization, and physically cell holding in the area that must be repaired; the use of adipose-derived stem cells is a promising strategy to promote adhesion and proliferation of chondrocytes to the scaffold as an autologous human feeder layer.     

Elastic and viscoelastic characterization of microcapsules for drug delivery using a force-feedback MEMS microgripper

This paper reports a monolithic, force-feedback MEMS (microelectomechanical systems) microgripper and its application to micro-scale compression testing of swollen hydrogel microcapsules at wet state during manipulation. The single-chip microgripper integrates an electrothermal microactuator and two capacitive force sensors, one for contact detection (force resolution: 38.5 nN) and the other for gripping force measurements (force resolution: 19.9 nN). With the capability of resolving gripping forces down to 19.9 nN and material deformations with a 20.5 nm resolution, the system quantified Young’s modulus values and viscoelastic parameters of alginate microcapsules (15–25 μm), demonstrating an easy-to-operate, accurate compression testing technique for characterizing soft, micrometer-sized biomaterials.     

The incretin pathway as a new therapeutic target for obesity

The global obesity epidemic fuelled by our obesogenic environment, and the prevention and treatment of obesity are some of the most important health-care challenges of our time. Although influenced largely by genetic factors, body mass index (BMI) is also heavily dependent upon environmental (principally dietary) factors. Whilst bariatric surgery often results in weight loss, its associated cost is prohibitive for widespread application. Current options for medical treatment of obesity are limited by recent withdrawals of Rimonabant and Sibutramine, enhancing the need for further development of novel weight-loss drugs.