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.

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.

Objective To observe the effects of low intensity electromagnetic fields (LIEMFs) in promoting the reconstruction of full skin loss wounds grafted with human epidermal stem cells (ESCs). Methods Fifty nude mice aged 7 to 8 weeks with full skin loss wounds were equally divided into 3 experimental subgroups ( 1 Hz, 10Hz and 50Hz) and two control groups (a cell suspension control group and a blank control group) , with ten mice each. In the 3 experimental subgroups and the cell suspension control group, ESCs separated from human foreskin and cultured in vitro were grafted to the wounds using collagen sponge scaffolds. The experimental subgroups were then stimulated with an LIEMF (magnetic field intensity 5mT) at the appropriate frequency for 30min/day for 15 days. The blank control group was put under the same conditions without the cell suspension and LIEMF. The healing rates of the wounds were observed, and tissue slices were stained and observed under a light microscope. The inner structure of the regenerating skin was observed using transmission electron microscopy. Results The ESCs were successfully grafted. A few human integrin β1 positive stained cells appeared in the regenerating skin. The average healing rates in the experimental subgroups were significantly superior to those of the control groups. Well differentiated epidermis and dermis could be seen in the regenerating skin in all of the experimental groups. The epidermis had more cell layers and was thicker than in the control groups. More desmosome, hemidesmosome and keratin filaments were seen among the epidemic cells of the experimental groups. Conclusions LIEMF promotes the healing of full skin loss wounds grafted with ESCs in nude mice, and can promote complete repair of skin defects and the regeneration of skin function.

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.

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.

Objective: To investigate the correlations of indexes of isokinetic muscle testing with grip, the circumference of muscle, the time up and go test(TUGT), and the distance of 6-minutes walk test(6MWT). And to identify the availability of isokinetic muscle testing in diagnosing sarcopenia in the elderly. Methods: A total of 27 elderly patients with sarcopenia admitted in rehabilitation department of our hospital from Jan.2017 to Dec.2017 were enrolled in this cross-sectional study.Patients were evaluated in many aspects, including comprehensive evaluation by the comprehensive assessment, the skeletal muscle mass detection by dual energy X-Ray absorptiometry, the power of gripping by dynamometer, the circumference of muscle of upper and lower extremities, the muscle strength by isokinetic muscle testing, the sports ability by TUGT and 6MWT. Results: Isokinetic muscle testing including the knee flexion, knee extension, elbow extension, wrist extension, TUGT, 6MWT, the power of left gripping, the circumference of left forearm muscle showed a negative correlations to the age(r=-0.54, -0.44, -0.52, -0.61, -0.53, -0.41 and-0.39, P<0.05). A positive correlation were observed between TUGT and the age(r=0.44, P<0.05). The positive correlations between every index in isokinetic muscles testing and the power of both left and right gripping were observed(r=0.66, 0.67, 0.67, 0.67, 0.56, 0.62, 0.54, 0.54, 0.64, 0.59, 0.59 and 0.56, P<0.05). The knee flexion, knee extension, elbow flexion, elbow extension and wrist extension of Isokinetic muscle testing showed a positive correlations to 6MWT(r=0.71, 0.65, 0.62, 0.60 and 0.59, P<0.05). The knee flexion, knee extension, elbow extension and wrist extension of isokinetic muscle testing showed a negative correlations to TUGT(r=-0.57, -0.52, -0.42 and-0.48, P<0.05). Every index of isokinetic muscle testing showed a positive correlations to the circumference of both forearms(r=0.45, 0.47, 0.52, 0.42, 0.41, 0.44, 0.49, 0.52、0.60, 0.54, 0.44 and 049, P<0.05). Conclusions Isokinetic muscle testing can accurately evaluate the changes of muscle strength in the elderly with sarcopenia.It can be considered as the reference index of motor function in diagnosing sarcopenia in the elderly.

AIM: To investigate the effect of liquorice extract on TGF-β1-induced myocardial fibroblast (CFs) fibrosis. METHODS: 10 ng/mL TGF-β1 induced CFs to establish myocardial fibrosis cell model. Fibrotic cells were treated with liquorice extract and the cell activity was detected by MTT assay. CCK-8 was used to detect the effect of liquorice extract on CFs proliferation. The expression of smooth muscle actin (α-SMA) was detected by immunofluorescence. Western blot was used to detect TGF-β1/Smad signaling pathway related proteins and p-Smad2, p-Smad3 expression levels. The mRNA expression levels of Smad2, Smad3 and Smad4 were detected by RT-PCR. RESULTS: Compared with the control group, there were statistically significant differences in cell activity (P<0.05). The cell proliferation rate of glycyrrhiza uralensis extract groups was significantly lower than that of TGF-β1 group (P<0.05). The expression levels of α-SMA and TGF-β1/Smad signaling pathway related proteins in 100 μg/mL liquorice extract were significantly lower than those in TGF-β1 group (P<0.05). CONCLUSION: Glycyrrhiza extract can improve the occurrence and development of TGF-β1-induced myocardial fibrosis, and its mechanism maybe related to the inhibition of TGF-β1/Smad signaling pathway.

The diagnostic technology of acute stroke by microwave imaging has the advantages of being non-ionizing, fast, small, and low-cost. Therefore, this technology is expected to become an auxiliary or alternative means to CT and MRI technology. As the signal transmitting and receiving device of the microwave imaging system, the antenna has an important influence on the performance of the imaging system. At present, there are many antennas with different performances used in imaging systems, but there is a lack of clear evaluation criteria for them. In this paper, several typical antennas were introduced, their advantages and disadvantages from the perspective of bandwidth and near-field were analyzed, and the common requirements of imaging systems for antennas and the performance indicators of various types of imaging systems were summarized. Moreover, the development trend of antenna technology for microwave imaging was pointed out to provide a reference for the study of stroke microwave imaging technology.