ABSTRACT
Objective To investigate whether the low-frequency pulsed electromagnetic fields (LF-PEMFs) can enhance the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) induced by bone morphogenetic protein 9 (BMP9). Methods We isolated CD146＋/STRO-1＋ cells (namely PDLSC) from periodontal ligament cells of healthy human premolars, transfected the PDLSC with BMP9-overexpressing recombinant adenoviruses (Ad-GFP-BMP9), exposed the cells to the different intensities of PEMF stimulation (15 Hz, 0.6，1.2，1.8，2.4，3.0 mT, 1 h/12 h), and then detected the expression of runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteopontin (OPN) and osteocalcin (OCN) by qRT-PCR and Western blotting. Results Overexpression of BMP9 significantly promoted the expression of osteogenic markers (Runx2, ALP, OCN and OPN) in PDLSC (P0.05). After the intervention with 1.2, 1.8, 2.4 and 3.0 mT PEMF, the expression levels of osteogenic markers in PDLSC were significantly higher than those exposed to BMP9 alone (P0.05), and reached the peak at 2.4 mT (P0.05), indicating that LF-PEMFs enhanced BMP9-induced osteogenic differentiation of PDLSC, and there was a “window effect”. Conclusion LF-PEMFs stimulation (15 Hz, 1.8 to 3.0 mT) can enhance BMP9-induced osteogenesis of hPDLSCs in vitro.
ABSTRACT
Objective To investigate the phased expression of gene and protein of NogoA and its receptor (NgR) that affects axon growth of spinal cord injury (SCI), and to explore the time window effect of electroacupuncture on SCI rats. Methods A total of 144 female Sprague-Dawley rats were randomly assigned to sham operation group (group A, n=48) and model group (n=96). In the model group, Allen's method was used to establish SCI rats model, and they were further subdivided into model control group (group B, n=48) and electroacupuncture group (group C, n=48). Group C received electroacupuncture on Dazhui (GV14), Yaoyangguan (GV3), bilateral Ciliao (BL32) and Zu-sanli (ST36) with loose-tight wave, for 20 minutes every day, one day, seven days and 14 days after modeling. The rats at every interventional therapy time were randomly subdivided into two subgroups, which accepted sev-en or 14 days of treatment. Groups A and B were killed and the injured spinal cord tissue was extracted one day, three days, seven days, 14 days and 28 days after modeling, group C at the corresponding time. The hind limb motor function was assessed with BBB score before all of rats were killed. Four samples at every time in each group were randomly selected to detect the expression of mRNA and protein of NogoA and NgR at different stage of SCI using reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting. Results The BBB score began to increase 14 days after modeling, and significantly increased until 28 days after model-ing (P<0.05), compared with one day, three days and seven days after modeling in group B. The BBB score in-creased in group C than in group B at all the time points (P<0.05), except 14 days after electroacupuncture one day after modeling. The BBB score was higher as electroacupuncture intervening seven days and 14 days after modeling than that at one day after modeling in group C, and no significant difference was found between seven days and 14 days of treatment at either electroacupuncture time point (P>0.05). The expression of gene and pro-tein of NogoA and NgR in group B was in the increasing tendency after SCI, and was at the peak until 21 days af-ter modeling, and was higher in group B than in group A at each time point (P<0.01). The expression of gene and protein of NogoA decreased at all the time points in group C than in group B (P<0.05), except seven days of elec-troacupuncture intervening one day after modeling in the expression of NogoA mRNA (P>0.05). The expression of gene and protein of NogoA and NgR was lower as electroacupuncture intervening 14 days after modeling than one day after modeling in group C (P<0.05). There was no significant difference in the expression of gene and protein of NogoA and NgR between electroacupuncture intervening 14 days and seven days after modeling, and seven days and one day after modeling (P>0.05); as well as between seven days and 14 days of treatment at each time point (P>0.05). Conclusion Elerctroacupuncture could improve the hind limb motor function, which may associate with the inhibition of the expression of gene and protein of NogoA and NgR in injured spinal cord of rats after SCI. Elerctroacu-puncture is effective in the treatment of SCI at the early time, however, it is much better in the recovery stage.
ABSTRACT
False and negative information has brought forth serious impacts on doctor-patient relationship in the new media era as a result of “Broken window effect”and “Butterfly effect”.The underlying reasons are herd mentality,the public’s need to vent their discontent,the subjectivity of information distribution on the Internet and lack of proper supervision and punishment mechanism.Medical Institutions should pay special attention to the new media,leveraging it to improve doctor-patient relationship by making official voice,guiding public opinion,solving problems,and providing comfortable social environment and rational public opinion environment on the Internet.