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Star-shaped PLA-heparin (sPLA-Hep) was prepared by coupling heparin to the star-shaped PLA (sPLA) reaction using carbonyldiimidazole (CDI) chemistry. Hydroxyl groups of sPLA were activated by CDI for the reaction with the remained...
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Star-shaped PLA-heparin (sPLA-Hep) was prepared by coupling heparin to the star-shaped PLA (sPLA) reaction using carbonyldiimidazole (CDI) chemistry. Hydroxyl groups of sPLA were activated by CDI for the reaction with the remained amino-terminal groups of heparin. The surface heparin content of sPLA-Hep was measured to be 1.43 mu g/cm~2. sPLA-Hep-coated surface has shown higher hydrophilicity than control surface. The clotting time of sPLA-Hep measured by activated partial thromboplastin time (APTT) was significantly prolonged when compared with sPLA and linear PLA-Hep. sPLA-Hep surface demonstrated lower protein adsorption and platelet adhesion than control sPLA surface. In addition, fibroblast culture on the sPLA-Hep surface showed the enhanced cell spreading area compared with the sPLA surface. Obtained results suggest that the incorporation of heparin to sPLA is effective in curtailing the surface induced-thrombosis and in manipulating the cell interaction. sPLA-Hep could be applied as blood/tissue compatible biodegradable materials for implantable medical devices and tissue engineering.
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Abstract In microsurgical anastomosis, non‐synthetic fibrin‐based adhesives have predominantly shown superior properties to synthetic cyanoacrylates, but they have hardly any clinical application. This study aims to investigate ...
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Abstract In microsurgical anastomosis, non‐synthetic fibrin‐based adhesives have predominantly shown superior properties to synthetic cyanoacrylates, but they have hardly any clinical application. This study aims to investigate the local and systemic effects of synthetically produced biodegradable adhesive VIVO when used in microsurgical anastomosis. VIVO is used in two different anastomosis procedures in the common carotid artery in a rat model: VIVO in addition to a temporary catheter (VIVO TC) and VIVO with a custom‐shaped memory nitinol stent (VIVO SM). Conventionally sutured anastomoses serve as controls (C). Tissue response is assessed by in vivo fluorescence imaging and histological examination. The systemic effects of biodegradation are measured using hematologic parameters and serum levels of transaminase activity and lactate dehydrogenase. Finally, the degree of local adhesion of the different anastomotic procedures is evaluated. Fluorescence imaging shows reduced inflammatory blood flow in the VIVO TC group. Histological analysis of the anastomosed vessels also reveals significantly more inflammation in C than in the two adhesive groups. The severity of VIVO adhesions proves acceptable, and no histotoxic effects of VIVO are detected. The data demonstrate that the synthetic tissue adhesive VIVO is a reliable and—compared to sutures—tissue‐friendly adhesive for microsurgical anastomoses.
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Titanium and its alloys are conventionally used to produce medical devices,but their biocompatibility has not yet been optimized. Surface modification,especially control of the surface roughness of titanium,is one strategy for imp...
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Titanium and its alloys are conventionally used to produce medical devices,but their biocompatibility has not yet been optimized. Surface modification,especially control of the surface roughness of titanium,is one strategy for improving biocompatibility and providing effective binding to hard tissue. However,the soft tissue compatibility of metallic materials is currently poorly understood,and effective techniques for tight binding between metal surfaces and soft tissue are still under development. Therefore,we here investigated whether the surface roughness of titanium affects fibroblast adhesion and proliferation. Our results showed that a surface roughness of ～100 nm reduces fibroblast function. On such surfaces,distinct focal adhesion was not observed. These findings improve the general understanding of the binding compatibility between soft tissues and metallic materials.
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Ideal percutaneous titanium implants request both antibacterial ability and soft tissue compatibility. ZnO structure constructed on titanium has been widely proved to be helpful to combat pathogen contamination, but the biosafety ...
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Ideal percutaneous titanium implants request both antibacterial ability and soft tissue compatibility. ZnO structure constructed on titanium has been widely proved to be helpful to combat pathogen contamination, but the biosafety of ZnO is always questioned. How to maintain the remarkable antibacterial ability of ZnO and efficiently reduce the corresponding toxicity is still challenging. Herein, a hybrid hydrogel coating was constructed on the fabricated ZnO structure of titanium, and the coating was proved to be enzymatically-degradable when bacteria exist. Then the antibacterial activity of ZnO was presented. When under the normal condition (no bacteria), the hydrogel coating was stable and tightly adhered to titanium. The toxicity of ZnO was reduced, and the viability of fibroblasts was largely improved. More importantly, the hydrogel coating provided a good buffer zone for cell ingrowth and soft tissue integration. The curbed Zn ion release was also proved to be useful to regulate fibroblast responses such as the expression of CTGF and COL-I. These results were also validated by in vivo studies. Therefore, this study proposed a valid self-adaptive strategy for ZnO improvement. Under different conditions, the sample could present different functions, and both the antibacterial ability and soft tissue compatibility were finely preserved.
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Our expanding understanding of the physiological and immunological conditions of the skin and, in particular, the aging face, has prompted a growing field of aesthetic technology. Restorative procedures are taking advantage of imp...
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Our expanding understanding of the physiological and immunological conditions of the skin and, in particular, the aging face, has prompted a growing field of aesthetic technology. Restorative procedures are taking advantage of improved and refined biotechnology, which continues to evolve at a rapid pace. Whereas surgical correction of skin laxity was the norm in years past, there are now many topical options available to encourage healthy, youthful skin, and an ever-growing, increasingly perfected depot of minimally invasive, injectable dermal volumizers and stimulators, collectively referred to as dermal fillers. The growth indicators for this market are as striking as the science. However, successful use of dermal fillers is not only a function of the quality of science leading to improved biocompatibility but also the "art" of client selection, filler application and vigilant follow up. Even the "ideal" filler is subject to unique interactions with both the practitioner and the patient. This articlepresents a review of the safety and efficacy of the most commonly used dermal fillers with emphasis on those approved for facial aesthetics. The subtleties of improved filler technologies that impact tissue acceptance and reaction, measures of effectiveness and a comparison of wrinkle-reduction outcomes, the nature and incidence of acute and chronic tissue reaction, and a discussion of recommended or preferred filler applications are presented.
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Abstract To evaluate the detoxification effect of a combination of Radix Glycyrrhizae (GU) and Semen Strychni (SN) from toxicokinetics and drug tissue distribution perspectives, decoctions of processed SN and codecoction of SN and...
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Abstract To evaluate the detoxification effect of a combination of Radix Glycyrrhizae (GU) and Semen Strychni (SN) from toxicokinetics and drug tissue distribution perspectives, decoctions of processed SN and codecoction of SN and GU (SGN) were prepared, and an HPLC‐ESI‐MS/MS method was developed to monitor the severe exposure level in 1‐month toxicokinetics and tissue distribution experiments to detect brucine and strychnine in rats. The toxicokinetic characteristics and tissue distribution before and after the addition of GU were analyzed. The method was successfully applied to evaluate the toxicokinetics and tissue distribution before and after the combination of SN and GU. The results show that GU decreased the blood concentration of toxic components in SN, and a double peak was observed in the drug time curve. The results of tissue distribution show that a combination of GU and SN significantly decreased the accumulation of toxic substances in metabolic organs and accelerated the clearance of toxic substances in the brain. These results provide a reference for the toxicity reduction mechanism of GU combined with SN.
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Novel difunctional oligolactone macromers have been synthesized by ring-opening oligomerization of various lactones (L-lactide, glycolide, p-dioxanone) in the presence of suitable diols (propane-1,2-diol, dianhydro-D-glucitol) and...
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Novel difunctional oligolactone macromers have been synthesized by ring-opening oligomerization of various lactones (L-lactide, glycolide, p-dioxanone) in the presence of suitable diols (propane-1,2-diol, dianhydro-D-glucitol) and subsequent endcapping of the formed oligolactones with methacrylate moieties. Based on these macromers, two fabrication procedures were developed to fabricate highly porous scaffolds and the material properties including in vitro biodegradation behaviour of the resulting polymeric scaffolds were investigated. Preliminary in vitro studies on the cytocompatibility of the fabricated scaffolds and on osteoblast cultivation on the optimized polymeric materials demonstrated that the oligolactide based polymer networks possess an excellent biocompatibility and that they are promising candidates as scaffolds in bone tissue engineering.
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Polymeric biomaterial was synthesized by copolymerizing 50:50 mol% of monomers, glycidyl methacrylate and methyl methacrylate. Iodine atoms were then grafted to the epoxide groups of glycidyl methacrylate units, rendering the copo...
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Polymeric biomaterial was synthesized by copolymerizing 50:50 mol% of monomers, glycidyl methacrylate and methyl methacrylate. Iodine atoms were then grafted to the epoxide groups of glycidyl methacrylate units, rendering the copolymer radiopaque. The percentage weight of iodine in the present copolymer was found to be as high as 23%. The iodinated copolymer showed higher glass transition temperature and thermal stability in comparison with unmodified polymer. Radiographic analysis showed that the copolymer possessed excellent radiopacity. The iodinated copolymer was cytocompatible to L929 mouse fibroblast cells. The in vivo toxicological evaluation by intracutaneous reactivity test of the copolymer extracts has revealed that the material was nontoxic. Subcutaneous implantation of iodinated copolymer in rats has shown that the material was well tolerated. Upon explantation and histological examination, no hemorrhage, infection or necrosis was observed. The samples were found to be surrounded by a vascularized capsule consisting of connective tissue cells. The results indicate that the iodinated copolymer is biocompatible and may have suitable applications as implantable materials.
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Fabrication of tissue engineering scaffolds with the use of novel 3D printing has gained lot of attention, however systematic investigation of biomaterials for 3D printing have not been widely explored. In this report, well-define...
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Fabrication of tissue engineering scaffolds with the use of novel 3D printing has gained lot of attention, however systematic investigation of biomaterials for 3D printing have not been widely explored. In this report, well-defined structures of polycaprolactone (PCL) and PCL-carbon nanotube (PCL-CNT) composite scaffolds have been designed and fabricated using a 3D printer. Conditions for 3D printing has been optimized while the effects of varying CNT percentages with PCL matrix on the thermal, mechanical and biological properties of the printed scaffolds are studied. Raman spectroscopy is used to characterise the functionalized CNTs and its interactions with PCL matrix. Mechanical properties of the composites are characterised using nanoindentation. Maximum peak load, elastic modulus and hardness increases with increasing CNT content. Differential scanning calorimetry (DSC) studies reveal the thermal and crystalline behaviour of PCL and its CNT composites. Biodegradation studies are performed in Pseudomonas Lipase enzymatic media, showing its specificity and effect on degradation rate. Cell imaging and viability studies of H9c2 cells from rat origin on the scaffolds are performed using fluorescence imaging and MTT assay, respectively. PCL and its CNT composites are able to show cell proliferation and have the potential to be used in cardiac tissue engineering.
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In this work we accomplished a study concerning the surface state of acrylic prosthetic biomaterials both optimized and non-optimized and we studied their compatibility on test animals. Various methods are seeking to improve the q...
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In this work we accomplished a study concerning the surface state of acrylic prosthetic biomaterials both optimized and non-optimized and we studied their compatibility on test animals. Various methods are seeking to improve the quality of implants and minimally invasive devices for body analysis, the increase of biocompatibility and resistance to corrosion of materials intended to come into contact with biological tissues. Poly (methyl methacrylate) is used in a wide range of applications and offersincreased resistance and color stability over time and it can be relatively easy to smooth and polish. The morphology and roughness of the surfaces in case of acrylic prosthetic biomaterials were analyzed by atomic force microscopy that provides qualitative information regarding the chemical uniformity from phase.
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