Objective To evaluate the cellular toxic and release of pharmaceutical dressing.Method Following the State standard GB/T14233.2-2005.the L929 cellular merphology was observed by inveded microscopy after 72h and proliferation of the cells was examined using mitochondrial function(MTT)assay.Relative growth rate (RGR)was calculated and cytotoxicity grade was evaluated by absorbency(OD)data.With PBS7.4 as dissolution media,and(32±0.5)℃as dissolution temperature,the release rate was determined with UV method with the determination wavelength of 288 nm and the dissolved liquid in 1/6,1/2,1,3,16,24,36 and 48 h.Results The average cell RGR of the pharmaceutical dressing is 91.25%and reaches 1 cytotoxicity grade.L929 cellular morphology is normal.Pharmaceutical dressing release accord to Higuchi equation,and the simulated equation is M_t/M_∞=0.3271t~(0.239).Conclusions Biologic compatibility of the pharmaceutical dressing is good,and the release of levofloxacin from the pharmaceutical dressing is sustained in vitro.

Various surgical technologies have been developed to minimize the risk of the operation. With continuous water flow being the dissector, a relatively bloodless operation and a clear view for the operator can be obtained. When applied to the adventitia and the soft tissue adjacent to the vascular structure, it is satisfying and the vessel and ureter can be protected perfectly if ligated selectively. The operation time is also shorter than the routine one. So, further studies of this technology are necessary.

Nano-hydroxyapatite has been widely used as reconstructive and prosthetic material for osseous tissue,owing to its excellent biocompatibility and tissue bioactivity.But the poor mechanical property of hydroxyapatite restricts its further application.In order to enhance the comprehensive performance of the material,many researches have been dedicated to the synthesization of the composite materials.This article reviews the main preparation methods of nano-hydroxyapatite and the advancement in research of its composite.The directions in this research area are described as well.

Shape-memory polymers(SMPs) can retain a temporary shape after pre-deformation at an elevated temperature and subsequent cooling to a lower temperature.When reheated,the original shape can be recovered.The development of the research on polyolefin,polyurethanes,polyester and some other shape-memory polymers were introduced and their applications in medical equipment were reviewed.

During rescue operations in case of armed conflicts in cities , terrorist attacks and public health emergencies , rescuers are always in danger .For this reason, search for and rescue robots have been used to search and evacuate the wounded .They have also become a hot issue in current robotics technology research ,promising a wide range of applications in civilian and military fields .This paper outlines the origin of rescue robot research ,course of development and classifica-tion, focuses on the developments of and future research of the U .S army on evacuation and rescue robots ,and finally pres-ents the problems and key technical difficulties facing the development of such robots .This paper is interded to improve re-search methods and design theories of rescue robotics .

AIM To study the effects of quateranary ammonium salt derivative (F 2) of haloperidol on ischemia and reperfusion injury in rat hearts. METHODS Ischemia and reperfusion injury in rat hearts was induced by occluding the left anterior descending coronary artery for 30 min and restoring blood reperfusion for 30 min. F 2 (1, 2, 4 mg?kg -1 , respectively) was intravenously injected before heart ischemia. Plasma creatine kinase (CK), creatine kinase isoenzyme MB(CK MB), lactate dehydrogenase(LDH),? Hydroxybutyrate dehydrogenase (HBDH), grutamic oxalacetic transaminase(GOT), superoxide dismutase (SOD) activity and malondiadehyde (MDA) contents were measured. The pathologic changes of ischemia and reperfusion myocardium were observed on the transmission electron microscopy. RESULTS F 2 reduced the release of CK,CK MB LDH,HBDH,GOT from I/R rat hearts, increased the activity of SOD and decreased the MDA contents. In F 2 (1mg?kg -1 ) group, the serum CK MB LDH HBDH concentration was lowered significantly (vs I/R group P

Objective To obtain the experimental data of vascular tissue engineering.MethodsThe vascular endothelial cells (VEC) and vascular smooth muscle cells (VSMCs) were acquired and cultured, and then seeded on vascular tissue engineering materials. The porous gelatin-chitosan scaffold with VSMCs was subcutaneously implanted, followed by the observation of the cell growth ten days later.ResultsThe two kinds of cells were successfully cultured and their morpholoical and immunohistochemical characteristics were consistent with vascular endothelial and VSMCs respectively. The VSMCs could grow extensively on the scaffold after the in vivo implantation. The scaffold were wrapped by the fibrous tissue ten days later after the in vitro implantation of VSMCs. The seed cells grew in the scaffold, and the vessel cavity seen in the center of the scaffold, was quite different from the normal vessel structure.ConclusionIt is feasible to implant the VSMCs with fibrin gels into the living body. The vessels reconstructed, though different from the normal structure, is similar to the embryo of the vessels.

ObjectiveTo investigate the feasibility of construction of engineered blood vessel using chitosan tube and fibrin gel as scaffold.MethodsVascular endothelial cells and smooth muscle cells were harvested from aortas of a rat, respectively. After expansion in vitro, vascular endothelial cells were seeded onto the inner surface of chitosan tube and smooth muscle cells mixed with fibrin gel seeded onto outer surface of the scaffold to construct engineered blood vessels. Inverted microscope, immunohistochemical staining and scanning electronic microscope were used to evaluate the construct.ResultsVascular endothelial cells formed monolayer and covered the inner surface of chitosan tube. Smooth muscle cells survived in the fibrin gel and grew in a 3-dimensional manner. ConclusionChitosan-fibrin gel may be potentially used as scaffold of engineered blood vessels.

Rat's osteoblasts cultured in vitro were stimulated by recombinant bovine basic fibroblast growth factor(rb-bFGF). After 1-2 days, the osteoblast grew long protuberance, the numbers of osteoblasts were greater than the control groups', the vitality of osteoblasts was better than that of control groups. After 1 hour, the expression of c-fos in osteoblast increased when compared with that in the control group. After the osteoblasts having been stimulated for 1-2 days, the expression of c-fos increased more conspicuously. These results show that bFGF can boost the osteoblast to grow and proliferate and can enhance the expression of c-fos gene. The increase of c-fos gene's expression may be an important step in the signal transformation process of all kinds of stimulation boosting osteoblast to proliferate.
Animals ; Cattle ; Cell Proliferation ; drug effects ; Cells, Cultured ; Fibroblast Growth Factor 2 ; pharmacology ; Gene Expression Regulation ; drug effects ; Genes, fos ; drug effects ; Osteoblasts ; cytology ; drug effects ; metabolism ; Proto-Oncogene Proteins c-fos ; metabolism ; Rats ; Rats, Wistar ; Recombinant Proteins ; pharmacology

Bone cells live in an environment heavily influenced by mechanical force. The development of bone tissue is dependent on the environment that surrounds it, both in vivo and in vitro. A loading stimulator on research of bone tissue-engineering was developed based on the mechanism of mechanosensation, scaffolding composites with mechanical strains with more physiologic magnitude, frequency components, and waveform. It also achieves the mechanical environment particularly in hard scaffold enough strong like cancellous bone. The device was tested using a reference scaffold made of better elastic plastic material. The experiment results showed that the device could be used in precision strain controls. Since the drive of the stimulator comes from the usage of smart material, piezoceramics, the strain at physiological level is controlled precisely. The stimulator provides a mechanical condition under which the effects of loading applied on bone tissue-engineering culture are conveniently investigated. Furthermore, after the stimulator is improved, it will be an appropriate bioreactor for bone tissue-engineering culture.
Bioreactors ; Bone and Bones ; cytology ; Cell Differentiation ; Cells, Cultured ; Humans ; Mechanotransduction, Cellular ; Osteoblasts ; cytology ; metabolism ; Stress, Mechanical ; Tissue Engineering ; instrumentation ; methods ; Tissue Scaffolds