Cyanobacteria is one of the promising microbial chassis in synthetic biology, which serves as a typical host for light-driven production. With the gradual depletion of fossil resources and intensification of global warming, the research on cyanobacterial cell factory using CO2 as carbon resource is ushering in a new wave. For a long time, research focus on cyanobacterial cell factory has mainly been the production of energy products, such as liquid fuels and hydrogen. One of the critical bottlenecks occurring in cyanobacterial cell factory is the poor economic performance, which is mainly caused by the inherent inefficiency of cyanobacteria. The problem is particularly prominent for these extremely cost-sensitive energy products. As an indispensable basis for modern industry, polymer monomers belong to the bulk chemicals with high added value. Therefore, increasing attention has been focused on polymer monomers which are superior in overcoming the economic barrier in commercialization of cyanobacterial cell factories. Here, we systematically review the progress on the production of polymer monomers using cyanobacteria, including the strategies for improving production, and the related technologies for the application of this important microbial cell factory. Finally, we summarize several issues in cyanobacterial synthetic biology and proposed future developing trends in this field.
Cyanobacteria ; Macromolecular Substances ; Polymers ; Synthetic Biology

OBJECTIVETo prepare the cross-linked chitosan/poly(acrylic acid)/poly (ethylene oxide) nanofibrous membrance loaded with pseudo-ginseng and to determine its characteristics.

METHODSPseudo-ginseng entrapped in chitosan, poly (acrylic acid), poly (ethylene oxide) nanofibrous membrane loaded with pseudo-ginseng was prepared by electrospinning and thermal treatment method. The surface morphology of fiber membrane was observed by scanning electron microscopy and the chemical structures were characterized by infrared spectroscopy; the thermal decomposition temperature was analyzed by the thermogravimetric analysis. UV-Vis spectra were used to evaluate the in vitro release properties.

RESULTSThe average diameter of the prepared nanofibrous particles was (181 ± 71) nm. The tensile strength of fiber membrane increased by 35.3% and the decomposition temperature increased from 197℃ to 208℃ after crosslinking. Compared with casting film, the structure of fiber membrane increased the release rate and the overall amount of active components from pseudo-ginseng.

CONCLUSIONThe preparation of chitosan fiber loaded with pseudo-ginseng is simple and the dispersion of pseudo-ginseng is homogeneous. This fibrous pseudo-ginseng exhibited good release performance, providing a new Chinese medicine formulation.

Acrylic Resins ; chemistry ; Chitosan ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Microscopy, Electron, Scanning ; Panax ; chemistry ; Polyethylene Glycols ; chemistry ; Temperature

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

Five kinds of pore-forming agents, including PEG-400, chitosan, the polymer of chitosan and glutin, CaCO3 and NazCO3, were used in this experiment to prepare fast responsive and pH sensitive Polyacrylic acid (PAAc) gel which could be used as the material of punctum plug. The mechanism and effects of pore-forming agents on PAAc gel were studied; besides, the experiment also assessed the effects of the three most effective pore-forming agents on gel's water retention and swelling rate. The results showed that the most suitable dose levels of PEG-400, the polymer and Na2CO3 were 1 ml, 0.8 ml and 1 ml respectively, and PEG-400 was most effective with the same dosage; the gel with PEG-400 as pore-forming agent could finish more than 95% of the swelling process in just 5 minutes, it is suitable for use as punctum plug material.
Acrylic Resins ; chemistry ; Carbonates ; chemistry ; Chitosan ; chemistry ; Hydrogels ; chemical synthesis ; chemistry ; Hydrogen-Ion Concentration ; Ophthalmic Solutions ; chemical synthesis ; chemistry ; Polyethylene Glycols ; chemistry ; Polymers ; Porosity

In this symposium, we reviewed the principle and development of time-resolved fluorescence anisotropy measurement. Its method of measurement, characteristics and applications in the research of biomacromolecule, configuration and molecular structure have been discussed. Its potential applications are also illustrated.
Fluorescence Polarization ; methods ; Macromolecular Substances ; Mathematics ; Models, Molecular ; Time Factors

No abstract available.
Acrylic Resins ; Breast ; Hydrogel

This is a review of recent progress in the study on environment sensitive hydrogel based on cyclodextrin and their most recent and relevant applications in the intelligent drug delivery systems. Based on relevant literatures, the development of environment sensitive hydrogel responsive to physical, chemical and biochemical stimuli was introduced, involving their categorization, design principles, mechanism of action and potential application. Various new types of intelligent drug delivery system, which responds to various triggers, could be constructed by using the cyclodextrin-based environment sensitive hydrogel. They made it possible to control the drug release freely. Although these hydrogels are still at their research stage, they have attracted considerable interest in the intelligent drug delivery system.
Acrylic Resins ; Cyclodextrins ; administration & dosage ; chemistry ; Delayed-Action Preparations ; Drug Carriers ; Drug Compounding ; Drug Delivery Systems ; Environment ; Hydrogels ; Hydrogen-Ion Concentration ; Light ; Polyethylene Glycols ; administration & dosage ; chemistry ; Polyvinyls ; administration & dosage ; chemistry ; Propylene Glycols ; administration & dosage ; chemistry ; Temperature

The combination of nanotechnology and molecular imprinting technique, including their application research in biomedical domain, provides a new solution to the problem of the substitutes for antibodies, enzymes, and other native biological structures as well as cell bracket materials. Nanocavity biomaterials with recognition specificity imprinted by using proteins as templates have numerous applications in biotechnology, medicine and so on. This review presents the aspects of molecular imprinting nanostructure involved in the biomacromolecules imprinting, and it explores the precent developments and achievements of nanomaterials for molecular imprinting technology.
Macromolecular Substances ; chemistry ; Molecular Imprinting ; trends ; Nanostructures ; Nanotechnology ; trends ; Proteins ; chemistry

OBJECTIVETo evaluate the pro-nucleating activity in 33.5 x 10(3) vesicular protein.

METHODSThe model biles were established according Kibe and Zhu. The pro-nucleating activity of 33.5 x 10(3) vesicular protein were examined by polarized light microscopy. The protein and its enzymatic deglycosylation and proteolysis fractions nucleation promoting activity were detected by cholesterol crystal growth assay.

RESULTS33.5 x 10(3) vesicular protein displayed apparent potency of pro-nucleation with activity of 0.310, and derived crystal growth curve indices It, Ig, Ic were presented as 0.57, 1.52, 1.63 respectively, but after treated by N-glycanase enzyme and pronase, no promoting activity were found.

CONCLUSIONThe 33.5 x 10(3) vesicular protein may be involved in the nucleation process of gallstone formation, which is regulated by its peptide and sugar chain.

Bile ; metabolism ; Cholelithiasis ; physiopathology ; Cholesterol ; metabolism ; Humans ; Macromolecular Substances ; Microscopy ; Models, Biological ; Protein Transport ; Proteins ; metabolism

The relation between the critical radius and the particle size distribution for generalized Ostwald type ripening processes whereby the mass transfer coefficient is modelled by a power law was derived. The critical radius is determined by the growth rate, the mass transfer coefficient and the mass balance, and is independent of whether the limiting stationary growth regime has been obtained.
Computer Simulation ; Crystallization ; methods ; Macromolecular Substances ; analysis ; chemistry ; Models, Chemical ; Models, Molecular ; Molecular Conformation ; Particle Size