Collagen contains abundant cell binding motifs, which are conducive to adhesion, migration, and differentiation, maintain cell vitality and promote cell proliferation. However, pure collagen hydrogel has some shortcomings such as poor mechanical properties, poor thermal stability and fast degradation. Numerous studies have shown that the properties of collagen can be improved by combining it with natural polysaccharides such as alginate, chitosan, hyaluronic acid and cellulose. In this paper, the research status and biological application fields of four kinds of composite hydrogels, including collagen-alginate composite hydrogels, collagen-chitosan hydrogels, collagen-hyaluronic acid hydrogels and collagen-cellulose hydrogels, were summarized. The common preparation methods of four kinds of composite hydrogels were introduced, and the future development direction of collagen-based composite hydrogels was prospected.
Hydrogels/chemical synthesis* ; Collagen/chemistry* ; Polysaccharides/chemistry* ; Alginates/chemistry* ; Hyaluronic Acid/chemistry* ; Chitosan/chemistry* ; Biocompatible Materials/chemistry* ; Humans ; Tissue Engineering/methods* ; Cellulose/chemistry* ; Tissue Scaffolds

Chest wall defect may be caused by many factors such as the resection of tumor and trauma, and the reconstruction of bone-defection is still the key point of thoracic surgery. With the development of material science, more and more new materials have been used in medical practice, which makes huge progress in the surgery of chest wall. However, none of these materials satisfy all the practical needs of the reconstruction. Recently, with the development of the capacity of computer, 3D-printing technology has been gradually used in clinical work, and the idea of individual treatment has been accepted by more and more people. The weakness of these materials may be solved by the new material and the application of individual treatment, which could also make great advance in chest wall surgery. This article will make a summary of the research on the reconstruction of chest wall.
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Animals ; Biocompatible Materials ; chemical synthesis ; chemistry ; Humans ; Printing, Three-Dimensional ; Reconstructive Surgical Procedures ; instrumentation ; methods ; Thoracic Neoplasms ; surgery ; Thoracic Wall ; surgery ; transplantation

To produce bionic bone material that is consistent with human bone in chemical composition and molecular structure using rat tail tendon collagen type Ⅰ.The type Ⅰcollagen derived from rat tail was extracted by acetic acid to form collagen fibers. The reconstructed collagen fibers were placed in the mineralized solution to mimic bone mineralization for 2-6 days. Bone mineralization was observed by transmission electron microscopy and electron diffraction.Collagen fibers with characteristic D-Band structure were reconstructed by using rat tail tendon collagen type Ⅰ extracted with acid hydrolysis method. Transmission electron microscopy and electron diffraction showed that calcium hydroxyapatite precursor infiltrated into the collagen fibers, and the collagen fibers were partially mineralized after 2 days of mineralization; the collagen fibers were completely mineralized and bionic bone material of typeⅠ collagen/calcium hydroxyapatite was formed after 6 days of mineralization.The collagen type Ⅰ can be extracted from rat tail tendon by acid hydrolysis method, and can be reformed and mineralized to form the bionic bone material which mimics human bone in chemical composition and the molecular structure.
Animals ; Biocompatible Materials ; chemical synthesis ; Bone Matrix ; chemistry ; growth & development ; Bone Substitutes ; chemical synthesis ; Bone and Bones ; anatomy & histology ; chemistry ; Calcification, Physiologic ; Collagen Type I ; biosynthesis ; chemistry ; ultrastructure ; Humans ; Hydroxyapatites ; chemistry ; Rats ; Tail ; Tendons ; chemistry ; ultrastructure ; Tissue Engineering ; methods

Silk fibroin (SF)/sodium alginate (SA) hydrogels can be used as drug injection materials. Homogenate was prepared by centrifugation of the pig myocardial extracellular matrix (PMM) and its modification of SF gel material. This paper observes and compares the different components SF, SF/SA, SF/SA/PMM to illustrate the SF/SA/PMM ternary material as a drug delivery composition material. This ternary material can shorten the gel time, and can make the gel form to be maintained better. Meanwhile, it makes the internal structure of the gel looser so that the hole wall becomes thinner and more conducive to the drug release. In addition, it has good biocompatibility proved by pathological analysis, and is able to enhance the mesenchymal stem cells growth activity, which has great significance in carrying out drug control release.
Alginates ; chemical synthesis ; chemistry ; Animals ; Biocompatible Materials ; chemical synthesis ; Delayed-Action Preparations ; chemistry ; Drug Carriers ; chemical synthesis ; chemistry ; Extracellular Matrix ; chemistry ; Fibroins ; chemical synthesis ; chemistry ; Glucuronic Acid ; chemical synthesis ; chemistry ; Hexuronic Acids ; chemical synthesis ; chemistry ; Hydrogels ; chemical synthesis ; chemistry ; Myocardium ; chemistry ; Rats ; Swine ; Tissue Extracts ; chemistry

The chitosan scaffolds with different deacetylated degree were prepared in this study. The morphology of scaffolds were observed using SEM, and the porosity, the water absorbing swelling ratio and the degradation were examined both in vitro and in vitro. The results showed that the chitosan scaffolds with different deacetylated degree exhibited three-dimensional structure with high porosity. With increasing of deacetylated degree, their porosities were 93.46%, 90.02% and 86.71%, respectively. The swelling ratios of chitosan scaffolds were 820%, 803% and 772%, respectively. At the fourth week, the degradation rates were 30.44%, 22.08% and 17.10% in vitro, respectively; while the corresponding rates were 57.48%, 40.23%, 29.53% in vivo respectively. The degradation rate of chitosan scaffold was negatively correlated to deacetylated degree. Furthermore, it showed that the speed of degradation in vivo was faster than that in vitro. We concluded that controlling the deacetylated degree of chitosan can provide a well-matched degradable scaffold material for the reparation of cartilage defects.
Absorbable Implants ; Acetylation ; Animals ; Biocompatible Materials ; Chitosan ; analogs & derivatives ; chemical synthesis ; chemistry ; Female ; Male ; Materials Testing ; Rats ; Rats, Sprague-Dawley ; Tissue Engineering ; Tissue Scaffolds ; chemistry

We examined the biocompatibility and the safety of a-calcium sulfate hemihydrate (CSH)/multi-walled carbon nanotube (MWCNT) composites for bone reconstruction application. The biocompatibility of the CSH/MWCNT composites was evaluated by the measures which taking L929 fibroblast cells cultured in the extracted liquid of the composite soaking solution and putting bone marrow stromal cells planted on the composite pellets in vitro, respectively. The cell proliferation was evaluated by MTT test and further observed using an inverted optical microscope and a scanning electric microscope. The toxicity of the composites was evaluated by acute and subacute systemic toxicity test. Long-term muscle and bone implantation in vivo tests were also conducted. L929 fibroblast cells grew well in the extracted liquid, as well as bone marrow stromal cells that could adhere on the surface of sample pellets and proliferated rapidly. MTT test showed that there were no significant differences between the experimental and control groups (P > 0.05). In vivo test manifested that the composites were no toxicity, no irritation to skin and good for bone defect reconstruction. It was proved that a-calcium sulfate hemihydrate (CSH)/multi-walled carbon nanotube (MWCNT) composites exhibited excellent biocompatibility for the potential application in bone tissue engineering.
Animals ; Biocompatible Materials ; chemistry ; Bone Marrow Cells ; cytology ; Bone Substitutes ; chemical synthesis ; chemistry ; Calcium Sulfate ; chemistry ; Cell Line ; Cell Proliferation ; Fibroblasts ; cytology ; Materials Testing ; Nanotubes, Carbon ; chemistry ; Rabbits ; Stromal Cells ; cytology ; Tissue Engineering ; methods ; Toxicity Tests

OBJECTIVETo investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin.

METHODSTwelve caries-free human primary molars were randomly divided into 2 groups. In group 1, each tooth was hemisected into 2 halves. One half was assigned to the control subgroup 1, which was bonded with a commercially available one-step self-etching adhesive according to the manufacturer's instructions; the other half was assigned to experimental subgroup 1, in which the adhesive was applied three times before light curing. In group 2, one split half tooth was bonded with a commercially available one-step self-etching adhesive according to the manufacturer's instructions; for the other half, three layers of adhesive were applied with each successive layer of light curing. Specimens were stored in 0.9% NaCl containing 0.02% sodium azide at 37℃ for 18 months and then were subjected to microtensile bond strength test and the fracture mode analysis.

RESULTSWhen the adhesive was applied three times before light curing, the bond strength of the experimental subgroup 1 was significantly higher than that of the control subgroup 1 (47.46∓13.91 vs. 38.12∓11.21 MPa, P<0.05). When using the technique of applying multiple layers of adhesive with each successive layer of light curing, no difference was observed in bond strength between the control subgroup and the experimental subgroup (39.40±8.87 vs. 40.87±9.33 MPa, P>0.05).

CONCLUSIONMultiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin when using the technique of light-curing after applying 3 layers of adhesive.

Acid Etching, Dental ; methods ; Adhesiveness ; Child ; Coated Materials, Biocompatible ; chemical synthesis ; chemistry ; pharmacology ; Dental Cements ; chemical synthesis ; chemistry ; pharmacology ; Dental Prosthesis ; Dental Restoration Failure ; Dentin ; chemistry ; drug effects ; Dentin-Bonding Agents ; pharmacology ; Electroplating ; methods ; Equipment Failure Analysis ; Humans ; Materials Testing ; Tensile Strength ; drug effects

This study compared a new type of polysaccharide-coated magnetic nanoparticles (in which the polysaccharide is derived from Angelica sinensis) with the dextran magnetic nanoparticles in terms of preparation, biocompatibility and tissue distribution in vivo and in vitro in order to examine the potential application of Angelica polysaccharide as a novel carrier in magnetic drug targeting (MDT). Magnetic nanoparticles were prepared by chemical co-precipitation. Their physical and chemical properties were determined by using the transmission electron microscope (TEM), laser particle size analyzer (DLS) and vibrating sample magnetometer (VSM), and their purity and structure by using X-ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR). The atomic absorption spectrometric method was performed for quantification of the iron content in different tissues. Histological sections were stained by Prussian blue staining to observe the disposition of magnetic nanoparticles in the liver and kidney. The results showed that both kinds of magnetic nanoparticles possessed small particle size, good dispersion and good magnetic properties. XRD showed the main component of the two magnetic nanoparticles was Fe(3)O(4) crystals, and FTIR proved Fe(3)O(4) was successfully coated by each polysaccharide, respectively. In vivo, Fe(3)O(4)-dextran accumulated in the liver, spleen and lung and Fe(3)O(4)-Angelica polysaccharide only in the spleen and lung. It was concluded that Angelica polysaccharide may be applied as a novel carrier in the preparation of magnetic nanoparticles.
Angelica sinensis ; chemistry ; Animals ; Coated Materials, Biocompatible ; chemical synthesis ; Liver ; chemistry ; Lung ; chemistry ; Magnetite Nanoparticles ; chemistry ; ultrastructure ; Male ; Materials Testing ; Organ Specificity ; Particle Size ; Polysaccharides ; chemistry ; Rats ; Rats, Sprague-Dawley ; Spleen ; chemistry ; Surface Properties ; Tissue Distribution

A novel chitosan derivant, N-octyl-N-arginine chitosan (OACS) with a mimetic structure of cell-penetrating peptides was synthesized by introducing hydrophilic arginine groups and hydrophobic octyl groups to the amino-group on chitosan's side chain. Structure of the obtained polymer was characterized by FT-IR and 1H NMR. The substitution degree of octyl and arginine groups was calculated through element analysis and spectrophotometric method, separately. The critical micelle concentration of OACS was 0.12 - 0.27 mgmL(-1) tested by fluorescence spectrometry. The solubility test showed OACS could easily dissolve in pH 1 - 12 solutions and self-assemble to form a micelle solution with light blue opalescence. The OACS micelles have a mean size of 158.4 - 224.6 nm, polydisperse index of 0.038 - 0.309 and a zeta potential of +19.16 - +30.80 mV determined by malvern zetasizer. AFM images confirmed free OACS micelle has a regular sphere form with a uniform particle size. MTT test confirmed that OACS was safe in 50 - 1 000 micromol-L(-1). The result of HepG2 cell experiment showed that the cell internalization of OACS micelles enhanced with increased substitution degree of arginine by 40 folds compared to chitosan. Thus, OACS micelles were a promising nano vehicle with permeation enhancement and drug carrier capability.
Arginine ; analogs & derivatives ; chemical synthesis ; chemistry ; metabolism ; Biocompatible Materials ; chemical synthesis ; chemistry ; Cell Survival ; Cell-Penetrating Peptides ; chemical synthesis ; chemistry ; Chitosan ; analogs & derivatives ; chemical synthesis ; chemistry ; Drug Carriers ; Hep G2 Cells ; Humans ; Magnetic Resonance Spectroscopy ; Micelles ; Nanoparticles ; Particle Size ; Polymers ; Solubility ; Spectroscopy, Fourier Transform Infrared

Polyamidoamine (PAMAM) dendrimers is synthesized by the American scientist, Tomalia, in 1985 and is now used widely in many fields such as gene carriers, photoelectric sensor, wastewater treatment, drug carriers and catalyst. The present paper mainly reviews the structure and methods of synthesis, celluar cytotoxicity, achievements of gene and drug carriers research, advancement and prospect of PAMAM as a carrier in glioma therapy. Besides, it also involves an outline for the future research of the radiotherapy for glioma.
Biocompatible Materials ; chemical synthesis ; chemistry ; Dendrimers ; chemical synthesis ; chemistry ; Drug Carriers ; Genetic Vectors