RESUMO
Objective To study the effect of electrical stimulation breath training on lung function of patients following pulmonary lobectomy. Methods 62 patients following pulmonary lobectomy were randomly allocated into experimental group (n=30 )and control group (n=32). The experimental group received a 4-week supervised electrical stimulation breath training program using an electric stimulus feedback trainer (20mins per time, 3 times per week);The control group received postoperative routine nursing. Cadiopulmonary function evaluation of 2 groups were tested before and after the experiment. The evaluation included the 6-min walking test (6MWD), FVC, FEV1,W,AT and VO2max/kg. Results After 4 week training, the value of 6MWD,W,FVC,FEV1 all improved, compared to the baseline value (P < 0.05) and the value of 6MWD,W,FVC,FEV1 were more obvious in experimental group, compared to control group(P<0.05). The AT value and the VO2max/kg value increased than the baseline value (P<0.05)and the improvement degree was more remarkable in experimental group than that in control group (P<0.05). Conclusion Electrical stimulation breath training can improve cardiopulmonary function of the patients following pulmonary lobectomy.
RESUMO
BACKGROUND:The repair and management of ful-thickness skin defects resulting from burns and chronic wounds remain a significant unmet clinical chal enge. Using epidermal stem cel s and keratinocyte growth factor for ful-thickness wound repair is a promising approach. Low-frequency electromagnetic fields which are a non-invasive physical stimulation therapy have been recognized as a good method to enhance wound healing. OBJECTIVE:To develop a new strategy to accelerate wound healing by transplanting transfected epidermal stem cel s and keratinocyte growth factor and treating with low-frequency electromagnetic fields in a mouse model. METHODS:Epidermal stem cel s from Sprague-Dawley neonatal rats were isolated and cultured in vitro, then the cel s were labeled with 5-bromo-2-deoxyuridine and transfected by Ad-KGF, a recombinant adenovirus carrying the keratinocyte growth factor. Mice were given to create ful thickness skin wound on the dorsum and randomly assigned to four groups:control group, transplantation of epidermal stem cel s group, transplantation of keratinocyte growth factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group. RESULTS AND CONCLUSION:The best healing pattern was observed in the keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group (P<0.05) at days 9 and 16. 5-Bromo-2-deoxyuridine labeled cel s existed in the wound in the treated groups at day 9. A significantly increased expression of endogenous keratinocyte growth factor was detected in the transplantation of Keratinocyte Growth Factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at day 16. A wel-advanced epithelialization was observed in transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at days 16 and 30. These results suggest that low-frequency electromagnetic fields enhanced wound healing fol owing the transplantation of keratinocyte growth factor gene modified epidermal stem cel s.
RESUMO
BACKGROUND:Bone marrow mesenchymal stem cel transplantation is considered as a promising therapy for spinal cord injury. How to more effectively promote the survival of bone marrow mesenchymal stem cel s in the area of spinal cord injury and to accelerate the recovery of motor function after spinal cord injury is a current study focus. Previous studies have found that low-frequency electromagnetic fields can promote bone marrow mesenchymal stem cel proliferation and differentiation, but whether the low-frequency electromagnetic fields can be applied to bone marrow mesenchymal stem cel transplantation for treatment of spinal cord injury requires further studies. OBJECTIVE:To discuss the effects of low-frequency electromagnetic fields on motor function of spinal cord injury rats after transplantation of bone mesenchymal stem cel s. METHODS:Sixty-four rat models of incomplete spinal cord injury at T 10 were established by compression method and then randomized into control group, transplantation group (bone mesenchymal stem cel transplantation), electromagnetic field group and combination group (electromagnetic field+bone mesenchymal stem cel transplantation). After successful modeling, bone mesenchymal stem cel s labeled with 5-bromo-2'-deoxyuridine were injected into the original injured site in the transplantation group and combination group, which were isolated and purified with the fast adherence method;while alpha-minimum essential medium was injected into the electromagnetic field group and control group for instead. At 24 hours post-operation, the electromagnetic field group and combination group were explored to low-frequency electromagnetic fields (frequency 50 Hz, magnetic indaction intensity 5 mT) for 60 minutes per day. RESULTS AND CONCLUSION:After cel transplantation for 21 days, the Basso, Beattie, and Bresnahan scores in the combination group was higher than the other groups (P<0.05). 5-Bromo-2'-deoxyuridine positive cel s grew wel , and integrated into the normal spine;syringomyelia was reduced, and the number of spinal neural cel s was increased in the combination group. In addition, glial fibril ary acidic protein expression was decreased in the combination group, while matrix metal oproteinase 2 expression was increased. It indicates that low-frequency electromagnetic fields could promote recovery of motor function in the spinal cord injury rats transplanted with bone mesenchymal stem cel s, which could be associated that low-frequency electromagnetic fields facilitate the survival of transplanted bone mesenchymal stem cel s, up-regulate the expression of matrix metal oproteinase 2, and reduce glial scar formation in the spinal cord injured site.
RESUMO
Objective To observe the effects of low frequency electromagnetic fields (LFEMFs) on the proliferation of human epidermal stem cells (hESCs) cultured in a three dimensional environment so as to provide an experimental basis for applying LFEMF in skin tissue engineering.Methods hESCs from human prepuces were isolated and purified by the method of rapid adherence to collagen type ⅣV. They were grafted into a type-I collagen sponge or chitosan scaffold in vitro, and then stimulated with different frequencies of LFEMF ( 1 Hz, 10 Hz or 50 Hz) at a magnetic field intensity of 5 mT for 30 min/d. The cells' growth and proliferation were tracked using hematoxylin and eosin (HE) and diamine pheny1 indole (DAPI) staining and observed under the scanning electron microscope at different time points ( on 2nd, 7th, 10th and 14th days of LFEMF intervention). The amounts of cell proliferation at every time point were analyzed and compared.Results LFEMFs of different frequencies showed significantly different efficacy in promoting hESC proliferation. The two scaffolds also showed significantly different effects.By the 10th day, hESCs had grown significantly better on collagen sponge scaffolds than on the chitosan ones. All LFEMF frequencies could promote proliferation of hESCs, but the differences in their effects were statistically significant.Conclusion Collagen sponge may be a preferable scaffold for hESCs cultured in vitro. Rapid proliferation of ESCs in three-dimensional settings can be promoted by LFEMF intervention. LFEMF has relatively great potential in skin tissue engineering.
RESUMO
BACKGROUND: Simple polyvinyl alcohol (PVA) has limited ability to cell adhesion. There are not generally accepted studies on improved effects of collagen protein modified polyvinyl alcohol on cell adhesion and proliferation.OBJECTIVE: To investigate the feasibility of PVA/type Ⅰ college (COL-Ⅰ) as anterior cruciate ligament (ACL) scaffolds in tissue engineering.DESIGN, TIME AND SETTING: The controlled observation experiment was performed at the Fourth Affiliated Hospital, Medical College. Ji'nan University, Guangzhou Red Cross Hospital, Guangzhou Institute of Trauma Surgery from August 2006 to October 2007.MATERIALS: COL-Ⅰ gel was produced by Guangzhou Institute of Trauma Surgery.METHODS: PVA filature was used to weave fascicular scaffolds. NIH-3T3 cell line and human ACL cells were in vitro incubated, amplified, and then implanted on the PVA/COL scaffolds.MAIN OUTCOME MEASURES: The growth of NIH-3T3 cell line and human ACL cells on the PVA/COL scaffolds and the secretion of extracellular matrix were observed using scanning electron microscope. Cell compatibility of PVA/COL scaffolds was assessed. Mechanics characteristic of PVA/COL scaffolds was measured by using the electric. tensile force apparatus. Mechanical property of PVA/COL scaffolds was analyzed using the SPSS 11.5 software package.RESULTS: NIH-3T3 cell line and human ACL cells on the PVA/COL scaffolds adhered, proliferated, and secreted extracellular matrix. NIH-3T3 cell line highly grew compared with human ACL cells on the PVA/COL scaffolds. The adhered number of NIH-3T3 cell line and human ACL cells was significantly increased on the PVA/COL scaffolds. NIH-3T3 cell line and human ACL cells presented well morphology on the PVA/COL scaffolds. COL-Ⅰ could promote the secretion of extracellular matrix from NIH-3T3 cells, but its effects on human ACL cells were not significant. Tensile force test showed that load-extension curve of the materials was identical to ACL of human and rabbits, and the scaffolds possessed strong flexibility. The maximal load, ultimate stress and elastic modulus were respectively 52.61 N, 14.96 MPa and 202.08 MPa.CONCLUSION: COL-Ⅰ accelerates the adhesion and proliferation of NIH-3T3 cell line and human ACL cells on the surface and in the pore of the PVA/COL scaffolds, promotes the secretion of extracellular matrix from NIH-3T3, and PVA filature material has mechanical property and good cell compatibility.
RESUMO
[Objective]To investigate the feasibility of the fabrication of tissue-engineered anterior cruciate ligament(ACL)in vitro by studying biocompatibility and mechanical property of the braided polyvinyl alcohol(PVA)materials.[Method]Firstly,human ACL cells and NIH3T3 cells were isolated,expanded in vitro and seeded onto the surface of the braided PVA scaffold materials,the adhesion,proliferation and three-dimensional growth of cells on the scaffold were observed by SEM.Secondly,the biomechanical properties of the braided PVA scaffold materials were measured with electro-biomechanical machine.[Result]The braided PVA scaffold materials had no cytotoxicity,ACL and NIH3T3 cells adhered,grew and proliferated well both on the surface and in the holes of the braided PVA scaffold materials.The maximum load,the maximum strain and ultimate tensile stress of the braided PVA scaffold materials respectively were 169.78?9.18N,11.67?1.38% and 52.21?2.88MPa.[Conclusion]The braided PVA scaffold materials possess good biomechanical properties and biocompatibility,it may become an ideal biomaterial for fabricating tissue-engineering ACL if the biomechanical properties can be improved.