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

The advances of industrial biotechnology highly depend on the development of industrial bioprocess researches. In China, we are facing several challenges because of a huge national industrial fermentation capacity. The industrial bioprocess development experienced several main stages. This work mainly reviews the development of the industrial bioprocess in China during the past 30 or 40 years: including the early stage kinetics model study derived from classical chemical engineering, researching method based on control theory, multiple-parameter analysis techniques of on-line measuring instruments and techniques, and multi-scale analysis theory, and also solid state fermentation techniques and fermenters. In addition, the cutting edge of bioprocess engineering was also addressed.
Bioengineering ; history ; Bioreactors ; Biotechnology ; Chemical Engineering ; China ; Fermentation ; History, 20th Century ; History, 21st Century

For energy security, air pollution concerns, coupled with the desire to sustain the agricultural sector and revitalize the rural economy, many countries have applied ethanol as oxygenate or fuel to supplement or replace gasoline in transportation sector. Because of abundant feedstock resources and effective reduction of green-house-gas emissions, the cellulosic ethanol has attracted great attention. With a couple of pioneers beginning to produce this biofuel from biomass in commercial quantities around the world, it is necessary to solve engineering problems and complete the economic assessment in 2015-2016, gradually enter the commercialization stage. To avoid "competing for food with humans and competing for land with food", the 1st generation fuel ethanol will gradually transit to the 2nd generation cellulosic ethanol. Based on the overview of cellulosic ethanol industrialization from domestic and abroad in recent years, the main engineering application problems encountered in pretreatment, enzymes and enzymatic hydrolysis, pentose/hexose co-fermentation strains and processes, equipment were discussed from chemical engineering and biotechnology perspective. The development direction of cellulosic ethanol technology in China was addressed.
Biofuels ; Biomass ; Biotechnology ; Cellulose ; chemistry ; Chemical Engineering ; China ; Ethanol ; chemistry ; Fermentation ; Hydrolysis

Among blood preparations, serum has been topically used in the management of various ocular diseases in ophthalmology. Like peripheral blood serum, umbilical cord blood serum contains a high concentration of essential tear components, growth factors, neurotrophic factors, vitamin A, fibronectin, prealbumin, and oil. Umbilical cord serum can provide basic nutrients for epithelial renewal and can facilitate the proliferation, migration, and differentiation of the ocular surface epithelium. Eye drops made from umbilical cord serum have been applied to treat various ocular surface diseases, including severe dry eye with or without Sjogren's syndrome, ocular complications in graft-versus-host disease, persistent epithelial defects, neurotrophic keratopathy, recurrent corneal erosions, ocular chemical burn, and surface problems after corneal refractive surgery. Because mesenchymal stem cells from umbilical cord blood can be used to regenerate corneal tissue and retinal nerve cells, umbilical cord serum might be applied for tissue engineering and regenerative medicine in the future.
Burns, Chemical ; Epithelium ; Fetal Blood ; Fibronectins ; Graft vs Host Disease ; Intercellular Signaling Peptides and Proteins ; Mesenchymal Stromal Cells ; Nerve Growth Factors ; Neurons ; Ophthalmic Solutions ; Ophthalmology ; Prealbumin ; Refractive Surgical Procedures ; Regenerative Medicine ; Retinaldehyde ; Serum ; Sjogren's Syndrome ; Tears ; Tissue Engineering ; Umbilical Cord ; Vitamin A

Gene synthesis is the most fundamental and widely used technique in biological research. The synthesis of DNA encoding regulatory elements, genes, pathways and entire genomes provides powerful ways to both test biological hypotheses and harness biology for our use. The emerging field of synthetic biology is generating insatiable demands for synthetic genes. And the past couple of years witnessed exciting new developments in microchip-based gene synthesis technologies. This review discusses the current methods of chemical DNA synthesis and gene assembly, as well as the latest engineering tools, technologies and trends which could potentially lead to breakthroughs in the development of accurate, low-cost and high-throughput gene synthesis technology. These new technologies are leading the field of synthetic biology to a higher level.
DNA ; chemical synthesis ; genetics ; Genes, Synthetic ; genetics ; Genetic Engineering ; methods ; Oligonucleotide Array Sequence Analysis

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

The aim of this study is to investigate a new method for preparing a biomimetic bone material-surface modified sintered bovine cancellous bone, and to improve its bioactivity as a tissue engineering bone. The prepared sintered bovine cancellous bones with the same size were randomly divided into two groups, immersing in 1 and 1. 5 times simulated body fluid (SBF), respectively. The three time periods of soak time were 7, 14, and 21 days. After sintered bone was dried, the surface morphology of sintered bone and surface mineralization composition were observed under scanning electron microscopy (SEM). By comparing the effect of surface modification of sintered bone materials, we chose the most ideal material and studied its pore size, the rate of the porosity, the compress and bend intensity. And then the material and the sintered bone material without surface modification were compared. The study indicated that sintered bone material immersed in SBF (1.5 times) for 14 days showed the best effect of surface modification, retaining the original physico-chemical properties of sintered bone.
Animals ; Biocompatible Materials ; chemical synthesis ; Biomimetic Materials ; chemical synthesis ; Bone Substitutes ; Bone and Bones ; chemistry ; drug effects ; Calcification, Physiologic ; physiology ; Cattle ; Chemical Phenomena ; Hydroxyapatites ; chemistry ; Porosity ; Surface Properties ; Tissue Engineering ; methods

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

Chitosan is a natural biopolymer and is made up of D-glucosamine subunits linked by beta-(1,4) glycosidic bond. In recent years, the application of chitosan has attracted more and more attention because of its good biological function in cell biology. The properties of chitosan-based biomaterial are attributed to the physical properties and chemical composition of chitosan. The author of this paper summarized recent related studies and progresses of the influence of physical properties of chitosan on cell activity and cell mechanics property at home and abroad. The findings show that most studies mainly focused on the influence of chitosan and cell activity, while few were on cell mechanics property. The related studies of the influence of chitosan on cell will contribute to the explanation for the mechanism of the interaction between chitosan and cell, and provide the theoretical support for the further study.
Animals ; Cell Adhesion ; drug effects ; Cell Differentiation ; drug effects ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Chemical Phenomena ; Chitosan ; chemistry ; pharmacology ; Humans ; Tissue Engineering ; Tissue Scaffolds ; chemistry

Strontium added into porous hydroxyaptite ceramics has the functions of improving its osseointegration, decreasing its dissolution rate and improving the bone density. Strontium-containing hydroxyaptite (Sr-HA) ceramics has been used as bone replacement and scaffold to treat the osteoporosis and bone default in clinic, but the mechanism of interfacial tissue response caused by the trace element Sr in Sr-HA ceramics still remains to be further studied. Four types of Sr-HA ceramic samples with different contents of Sr were prepared by microwave plasma sintering for testing the response of the soft tissue implanted in dog muscles in our laboratory. The contents of Sr element in the samples are 0 mol%, 1 mol%, 5 mol%, and 7 mol%, respectively. The samples were implanted in the muscle of the dogs for 4 weeks, 8 weeks and 12 weeks, respectively. The histological observations at the end of each period showed that the irritant ranking increased with the content of Sr in Sr-HA ceramics at the end of 12 weeks, and there were rich bone tissue in Sr-HA ceramic samples with 5 mol% Sr element. The overdose of element Sr is harmful to soft tissues. When the content of Sr in Sr-HA ceramic was below 5 mol%, the soft tissue response was very slight and the new bones were induced to grow well.
Animals ; Bone Substitutes ; chemical synthesis ; Ceramics ; chemical synthesis ; chemistry ; Dogs ; Durapatite ; chemical synthesis ; chemistry ; Female ; Male ; Muscle, Skeletal ; surgery ; Osseointegration ; physiology ; Porosity ; Prostheses and Implants ; Strontium ; chemistry ; Tissue Engineering