Adsorption of 117mSn(Ⅳ)-EDTMP on hydroxyapatite and collagen

Some organic phosphines labeled with 117mSn(Ⅳ) have been provedpromising for imaging and pain palliation of bone tumor. In this paper, a prelimi-nary investigation on the adsorption characteristics of EDTMP (ethelenediaminete-tramethylene phosphoric acid) labeled with 117mSn(Ⅳ) on HA(hydroxyapatite) andcollagen, and an investigation on the adsorption mechanism of 117mSn(Ⅳ)-EDTMPon HA was presented.``     

Radiation demineralised bone enhanced osteoinductive capacity after transplantation

Using a mediating alkyne gas during the radiation treatment prevents the degradation of natural and synthetic polysaccharides and proteins. The product has higher viscosity and is more elastic than the original material and, therefore, gives enhanced functionality. Protein, within demineralised bone, too can be modified to give enhanced osteoinductive capacity after transplantation. Thus new functionalities can be achieved from the new products produced in food and medical products.     

Electrospinning of collagen-chitosan complex

The collagen-chitosan complex nanofibers have been prepared for the first time by electrospinning. The mixed HFP/TFA (the volume ratio of 90/10) was found to be the appropriate solvent for electrospinning. The concentration of the spinning solution and the ratio of chitosan/collagen were varied and adjusted to get smooth nanofibers. It was found that the diameter of the spun fibers became thick with the concentration of the solution increasing and became fine with the ratio of the chitosan/collagen increasing. We have characterised the molecular interactions in collagen-chitosan complex by Fourier transform infrared spectroscopy. The spun fibers are designed to mimic the native extracellular matrix for tissue engineering and to develop functional biomaterials.     

Effect of various parameters on sodium dodecyl sulfate (SDS) flux through a collagen membrane

The influence of various experimental parameters on the flux of sodium dodecyl sulfate (SDS) through a collagen membrane has been studied. The variables evaluated were donor concentration, time, temperature, pH and ionic strength. Data on the influence of both surfactant concentration and time on surfactant diffusion through the collagen film allow one to postulate a diffusion process mainly of the monomeric type. This diffusion mechanism based on surfactant monomers has been corroborated by studying the effect of ionic strength. Thisin vitro technique could be a useful tool to predict the effect of diverse experimental parameters on the percutaneous absorption of surfactants.     

应用骨形成蛋白与胶原膜复合物修复大鼠颅骨缺损

目的探讨骨形成蛋白(BMP)与胶原膜复合物(复合膜)修复大鼠颅骨缺损的效果。方法将BMP与胶原膜复合,在大鼠颅骨制备骨缺损,分别采用双侧覆盖复合膜、外侧覆盖复合膜进行治疗,以外侧覆盖胶原膜作为平行对照,并设空白对照。于术后2、4、6周,取标本进行X线检查及组织学观察。结果 两个覆盖复合膜组的缺损成骨面积百分比明显高于覆盖胶原膜的平行对照组(P<0.01)。术后4、6周,双侧覆盖复合膜组的成骨面积百分比明显大于单侧覆盖复合膜组(P<0.05)。双侧覆盖复合膜组的缺损术6周后已达骨性愈合。结论BMP与胶原膜复合既具有机械性阻挡作用,又具有骨诱导性,能加速骨缺损愈合。     

Multiscale computation for bioartificial soft tissues with complex geometries

The mechanical function of soft collagenous tissues is inherently multiscale, with the tissue dimension being in the centimeter length scale and the underlying collagen network being in the micrometer length scale. This paper uses a volume averaging multiscale model to predict the collagen gel mechanics. The model is simulated using a multiscale component toolkit that is capable of dealing with any 3D geometries. Each scale in the multiscale model is treated as an independent component that exchanges the deformation and average stress information through a scale-linking operator. An arterial bifurcation was simulated using the multiscale model, and the results demonstrated that the mechanical response of the soft tissues is strongly sensitive to the network orientation and fiber-to-fiber interactions.     

气-液界面胶原蛋白单层膜研究

利用Langmuir-Blodgett（LB）技术研究了纤维蛋白I-型胶原蛋白在去离子水亚相、氯化钙亚相和碳酸氢钙亚相上的成膜行为和形貌．表面压．面积等温（π-A）曲线表明纤维蛋白I-型胶原蛋白在三种亚相上均具有较好的成膜性能,利用原子力显微镜（AFM）对转移到新鲜解理的云母表面的单层I-型胶原蛋白的形貌进行了分析,AFM结果表明胶原蛋白在界面聚集成多个胶原分子组成的束装．该研究结果对于理解胶原在气．液界面的成膜性能具有重要意义,同时对探究纤维蛋白I-型胶原蛋白调节下的生物矿化作用具有重要的指导意义．     

Collagen network as the scaffold for spontaneously distributed optical resonators

The idea behind this work was to acquire one dimensional lasing in the Rhodamine 6G dye doped collagen fibers with the control of random lasing phenomenon properties by changing the dye molecular arrangement. We show that a simple manipulation of the dye concentration in biopolymeric fibril matrix bulk and an additional use of α-cyclodextrin (α-CD) molecules determine formation of specific dye aggregates and as a consequence the shift of the random lasing emission wavelength in the desired direction. The analysis of the light transport mean free path in function of the dye and (α-CD) concentration was done with the use of coherent back scattering technique.     

The effect of rippled graphene sheet roughness on the adhesive characteristics of a collagen–graphene system

A great amount of effort has been made in order to reach a more precise understanding of the adhesion phenomenon that happens as a vital component of several biological systems. Therefore, a firm understanding of the important factors that influence this phenomenon is of special importance in triggering the adhesive characteristics of different biological, bio-inspired and synthetic materials in fields such as tissue engineering.In this study the adhesive characteristics of a multi-material system consisting of the frequently used synthetic material, graphene, in the form of armchair-configuration sheets, and an important biological filament which is type 1 Collagen consisting of 3 alpha helices, has been studied in detail. The main emphasis of this study is placed on understanding the effects of the roughness characteristics of the inorganic elements which are the graphene sheets on the overall adhesive features of the system which are quantified within the framework of two main criteria: adhesion energy and peeling force. At first, the methodology used in order to obtain graphene sheets with various roughness values is described in detail. The abovementioned criteria are then evaluated through Molecular Dynamics (MD) modeling of the system in the NAMD simulation software environment and various simulation scenarios are studied.     

Low Dietary c9t11-Conjugated Linoleic Acid Intake from Dairy Fat or Supplements Reduces Inflammation in Collagen-Induced Arthritis

Dietary cis‐9,trans‐11 (c9t11) conjugated linoleic acid (CLA) fed at 0.5 % w/w was previously shown to attenuate inflammation in the murine collagen‐induced (CA) arthritis model, and growing evidence implicates c9t11‐CLA as a major anti‐inflammatory component of dairy fat. To understand c9t11‐CLA's contribution to dairy fat's anti‐inflammatory action, the minimum amount of dietary c9t11‐CLA needed to reduce inflammation must be determined. This study had two objectives: (1) determine the minimum dietary anti‐inflammatory c9t11‐CLA intake level in the CA model, and (2) compare this to anti‐inflammatory effects of dairy fat (non‐enriched, naturally c9t11‐CLA‐enriched, or c9t11‐CLA‐supplemented). Mice received the following dietary fat treatments (w/w) post arthritis onset: corn oil (6 % CO), 0.125, 0.25, 0.375, and 0.5 % c9t11‐CLA, control butter (6 % CB), c9t11‐enriched butter (6 % EB), or c9t11‐CLA‐supplemented butter (6 % SB, containing 0.2 % c9t11‐CLA). Paw arthritic severity and pad swelling were scored and measured, respectively, over an 84‐day study period. All c9t11‐CLA and butter diets decreased the arthritic score (25–51 %, P < 0.01) and paw swelling (8–11 %, P < 0.01). Throughout the study, plasma tumor necrosis factor (TNFα) was elevated in CO‐fed arthritic mice compared to non‐arthritic (NA) mice but was reduced in 0.5 % c9t11‐CLA‐ and EB‐fed mice. Interleukin‐1β and IL‐6 were increased in arthritic CO‐fed mice compared to NA mice but were reduced in 0.5 % c9t11‐CLA‐ and EB‐fed mice through day 42. In conclusion, 0.125 % c9t11‐CLA reduced clinical arthritis as effectively as higher doses, and decreased arthritis in CB‐fed mice suggested that the minimal anti‐inflammatory levels of c9t11‐CLA might be below 0.125 %.