As an important auxiliary material, adhesive materials have many important applications in various fields including but not limited to industrial packaging, marine engineering, and biomedicine. Naturally occurring adhesives such as mussel foot proteins are usually biocompatible and biodegradable, but their limited sources and poor mechanical properties in physiological conditions have limited their widespread uses in biomedical field. Inspired by the underwater adhesion phenomenon of natural organisms, a series of biomimetic adhesive materials have been developed through chemical or bioengineering approaches. Notably, some of those synthetic adhesives have exhibited great promise for medical applications in terms of their biocompatibility, biodegradability, strong tissue adhesion and many other attractive functional properties. As natural adhesive materials possess distinctive "living" attributes such as environmental responsiveness, self-regeneration and autonomous repairs, the development of various biologically inspired and biomimetic adhesive materials using natural adhesives as blueprints will thus be of keen and continuous interest in the future. The emerging field of synthetic biology will likely provide new opportunities to design living glues that recapitulate the dynamic features of those naturally occurring adhesives.
Adhesives ; Animals ; Biocompatible Materials ; Biomimetic Materials ; chemistry ; Biomimetics ; Bivalvia

To investigate if the surface modification of intraocular lens (IOL) is efficient in the prevention of posterior capsular opacification (PCO), the acrylic surface of intraocular lens (Acrysof(R)) was polymerized with polyethylene glycol (PEG-IOL). The human lens epithelial cells (1x10(4) cells/mL) were inoculated on PEG grafted or unmodified acrylic lenses for the control. The adherent cells on each IOL surface were trypsinized and counted. The every PEG-IOL was implanted in 20 New Zealand rabbits after removal of crystalline lens. The formations of PCO were checked serially through retroilluminated digital photography, and the severity scores were calculated using POCOman(R). The cell adherence patterns on each IOL were examined by scanning electron microscopy. As a result, the mean number of adherent cells of PEG-IOL (3.2+/-1.1x10(3)) tended to be smaller than that of the acrylic controls (3.6+/-1.9x10(3)) without a statistical significance (p=0.73). However, the mean severity of PCO formation in PEG-IOL was significantly lower than that in the control during the third to sixth weeks after surgery. Scanning electron microscopy revealed that the more patch-like cells were found firmly attached to the IOL surface in control than in the PEG-IOL. Conclusively, PEG polymerization to the acrylic IOL would possibly lessen the formation of PCO after cataract removal.
Acrylic Resins/chemistry ; Biocompatible Materials ; Cataract/metabolism/*therapy ; Cell Adhesion ; Humans ; Lens Implantation, Intraocular/*methods ; Lens, Crystalline/cytology/ultrastructure ; Microscopy, Electron, Scanning ; Polyethylene Glycols/*chemistry/metabolism ; Time Factors

The management of nuclear, biological and chemical (NBC) terrorism events is critical to reducing morbidity and mortality in the next decade; however, initial patient care considerations and protective actions for staff are unfamiliar to most front-line clinicians. High explosive events (bomb and blast) remain the most common type of terrorism and are easy to detect. Conversely, some types of terrorist attacks are more likely to be unsuspected or covert. This paper explains the current threat of terrorism and describes clues for detection that an event has occurred. Specific criteria that should lead to a high suspicion for terrorism are illustrated. The manuscript outlines initial actions and clinical priorities for management and treatment of patients exposed to nuclear/radiological, biological, chemical and combined agents (for example an explosion involving a chemical agent). Examples of terrorist events include: a nuclear explosion, an aerosolised release of anthrax (biological), dissemination of sarin in a subway (chemical), and the detonation of a radiologic dispersion device or "dirty bomb" (combined explosive and radiological). Basic principles of decontamination include potential risks to healthcare providers from secondary exposure and contamination. Unique issues may hinder clinical actions. These include coordination with law enforcement for a crime scene, public health entities for surveillance and monitoring, hazardous materials teams for decontamination, and the media for risk communications. Finally, the importance of personal preparedness is discussed.
Biological Warfare Agents ; Chemical Warfare Agents ; Civil Defense ; Nuclear Weapons ; Terrorism

STATEMENT OF PROBLEM: Recently, titanium has become popular as superstructure material in implant dentistry because titanium superstructure can be easily milled by means of computer-aided design and manufacture (CAD/CAM) technique. But retention form such as nail head or bead cannot be cut as a result of technical limitation of CAD/CAM milling and bond strength between titanium and porcelain is not as strong as that of conventional gold or metal alloy. PURPOSE: The objective of this study was to evaluate the shear bond strength of three different materials: heat curing resin, composite resin, porcelain which were bonded to grade II commercially pure Titanium (CP - Ti). MATERIAL AND METHODS: Thirty seven CP - Ti discs with 9 mm diameter, 10 mm height were divided into three groups and were bonded with heat curing resin (Lucitone 199), indirect composite resin (Sinfony), and porcelain (Triceram) which were mounted in a former with 7 mm diameter and 1 mm height. Samples were thermocycled for 1000 cycles at between 5 - 55 degrees C. Shear bond strength (MPa) was measured with Instron Universal Testing Machine with cross head speed of 1 mm/min. The failure pattern was observed at the fractured surface and divided into adhesive, cohesive, and combination failure. The data were analyzed by one-way ANOVA and Scheffe's multiple range test (alpha= 0.05). RESULTS: Lucitone 199 (17.82 +/- 5.13 MPa) showed the highest shear bond strength, followed by Triceram (12.97 +/- 2.11 MPa), and Sinfony (6.00 +/- 1.31 MPa). Most of the failure patterns in Lucitone 199 and Sinfony group were adhesive failure, whereas those in Triceram group were combination failure. CONCLUSION: Heat curing resin formed the strongest bond to titanium which is used as a CAD/CAM milling block. But the bond strength is still low compared with the bond utilizing mechanical interlocking and there are many adhesive failures which suggest that more studies to enhance bond strength are needed.
Acrylic Resins ; Adhesives ; Alloys ; Ceramides ; Collodion ; Computer-Aided Design ; Dental Porcelain ; Dentistry ; Head ; Hot Temperature ; Nails ; Retention (Psychology) ; Titanium

The article presents an overview of the basic data influencing the choice of materials for the manufacture of self-expanding metallic stents to be implanted into gastrointestinal tract, particularly esophageal stents. The data are evaluated primarily in terms of the manufacturer of stents. The text emphasizes not only the importance of the materials themselves, but also the biological environment in which the stent is used. Brief history of materials used in gastrointestinal stents mentions stainless steel, cobalt-chromium and nickel titanium alloys and polymers (polyester and polydioxanone). The text describes the properties of metal materials (composition, corrosion, mechanical properties) with particular focus on nickel-titanium alloy—nitinol. It lists advantages and disadvantages of nitinol. At the end of the review the authors briefly present their opinion on future materials of gastrointestinal stents and their covering.
Alloys ; Biocompatible Materials ; Biomedical and Dental Materials ; Corrosion ; Gastrointestinal Tract ; Nickel ; Polymers ; Self Expandable Metallic Stents ; Stainless Steel ; Stents* ; Titanium

Human-like collagen (HLC) was cross-linked with hyaluronic acid by genipin in different ratio. The concentrations of hyaluronic acid in the mixture were 0, 0.01%, 0.05% and 0.1%. The blood vessel tubular grafts were then fabricated by freeze-drying. Microstructure, element composite, mechanical properties, cytotoxicity grade, and biocompatibility of different vascular scaffold groups were studied by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), tensile test, burst pressure experiment, cytotoxicity experiment, endothelial cells planted in blood vessel scaffolds and hypodermic embedding of mice. The results showed that HLC-HA (0.05%) tubular scaffold exhibited interconnected well-distributed and porous structure and porosity of 94.38%; achieved the desirable mechanical property with stress of (1000.8 +/- 7.9) kPa and burst pressure of (1058.6 +/- 8.2) kPa, hypocytotoxicity, favourable cytocompatibility, hisocompatibility and disposition of degradation.
Adhesives ; chemistry ; Animals ; Biocompatible Materials ; chemistry ; Biomimetic Materials ; chemistry ; Blood Vessels ; drug effects ; physiology ; Collagen ; chemistry ; Humans ; Hyaluronic Acid ; chemistry ; Iridoid Glycosides ; Iridoids ; chemistry ; Materials Testing ; Mice ; Tissue Engineering ; instrumentation ; methods ; Tissue Scaffolds

Poly-N-isopropylacrylamide (PNIPAAm) is a new kind of intelligent material. It shows favorable thermo sensitivity because of the structure of hydrophilic acrylamino and hydrophobic isopropyl. PNIPAAm also shows good biocompatibility and non-toxicity. All the characters as above make it an ideal extra cellular matrix material for tissue engineering. This paper reviews its application in tissue engineering.
Acrylamides ; chemistry ; Acrylic Resins ; Animals ; Biocompatible Materials ; Hot Temperature ; Humans ; Polymers ; chemistry ; Tissue Engineering ; Tissue Scaffolds

In the process of repairing of bone defects, bone scaffold materials need to be implanted to restore the corresponding tissue structure at the injury. At present, the repair materials used for bone defects mainly include autogenous bone, allogeneic bone, metal materials, bioceramics, polymer materials and various composite materials. Different materials have demonstrated strong reconstruction ability in bone repair, but the ideal bone implants in the clinic are still yet to be established. Except for autogenous bone, other materials used in bone defect repair are unable to perfectly balance biocompatibility, bone formation, bone conduction and osteoinduction. Combining the latest advances in materials sciences and clinical application, we believe that composite materials supplementedwith Chinese medicine, tissue cells, cytokines, trace elements, etc. and manufactured using advanced technologies such as additive manufacturing technology may have ideal bone repair performance, and may have profound significance in clinical repair of bone defects of special type. This article reviewed to the domestic and foreign literature in recent years, and elaborates the current status of bone defect repair materials in clinical application and basic research in regard to the advantages, clinical options, shortcomings, and how to improve the autogenous bone, allogeneic bone and artificial bone materials, in order to provide a theoretical basis for clinical management of bone defects.
Acrylic Resins ; Biocompatible Materials ; Bone Substitutes ; Bone and Bones ; Osteogenesis ; Tissue Engineering ; Tissue Scaffolds

In recent years, due to the dramatic increase in the number of surgical operations, there has been a clinically significant increase in the demand for medical adhesives capable of cohesion in a moist environment that can overcome blood or tissue fluids . As the understanding of the mechanisms and key elements of natural adhesion to aquatic organisms continues to develop, a variety of medical adhesives have been developed by mimicking adhesion procedures or utilizing key functional groups. This article will review the classification, adhesion mechanism, use, research progress and development prospects of biomedical adhesives inspired by aquatic organisms octopus and mussels.
Adhesives ; Animals ; Biomimetic Materials ; Bivalvia

The purpose of this study was to investigate the influence of various occlusal loading sites and directions on the stress distribution of the cervical composite resin restorations of maxillary second premolar, using 3 dimensional (3D) finite element (FE) analysis. Extracted maxillary second premolar was scanned serially with Micro-CT (SkyScan1072; SkyScan, Aartselaar, Belgium). The 3D images were processed by 3D-DOCTOR (Able Software Co., Lexington, MA, USA). HyperMesh (Altair Engineering, Inc., Troy, USA) and ANSYS (Swanson Analysis Systems, Inc., Houston, USA) was used to mesh and analyze 3D FE model. Notch shaped cavity was filled with hybrid (Z100, 3M Dental Products, St. Paul, MN, USA) or flowable resin (Tetric Flow, Vivadent Ets., FL-9494-Schaan, Liechtenstein) and each restoration was simulated with adhesive layer thickness (40 microm). A static load of 200 N was applied on the three points of the buccal incline of the palatal cusp and oriented in 20degrees increments, from vertical (long axis of the tooth) to oblique 40degrees direction towards the buccal. The maximum principal stresses in the occlusal and cervical cavosurface margin and vertical section of buccal surfaces of notch-shaped class V cavity were analyzed using ANSYS. As the angle of loading direction increased, tensile stress increased. Loading site had little effect on it. Under same loading condition, Tetric Flow showed relatively lower stress than Z100 overall, except both point angles. Loading direction and the elastic modulus of restorative material seem to be important factor on the cervical restoration.
Acrylic Resins ; Adhesives ; Axis, Cervical Vertebra ; Bicuspid ; Chimera ; Composite Resins ; Elastic Modulus ; Finite Element Analysis ; Polyurethanes