Preliminary study on treatment of mandibular osteoradionecrosis by autologous bone marrow mesenchymal stem cells in miniature pigs / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the treatment effect of mandibular osteoradionecrosis (ORN) by autologous bone marrow mesenchymal stem cells (BMMSC) in miniature pigs.</p><p><b>METHODS</b>Six miniature pigs with mandibular ORN (25 Gy) were used. BMMSC were separated and cultured in vitro and then implanted on to the premolded hydroxyapatite-tricalcium phosphate (HA-TCP). The BMMSC-HA-TCP complexes were implanted into the defective area of mandibular ORN in 4 animals. Implantation of only HA-TCP in 2 animals served as control. Gross observation, spiral CT, coronary CT and histopathologic examination were carried out.</p><p><b>RESULTS</b>Fistula disappeared in animals with BMMSC-HA-TCP complexes 3 months after implantation, while fistula was found in controls. Spiral CT analysis showed that cortical bone repair were found 4 months after BMMSC-HA-TCP complexes implantation, while bone damage (cortical and cancellous bone fracture) increased in controls. Histopathologic examination revealed that 4 months later after BMMSC-HA-TCP complexes implantation, new bone formation and bone cells could be observed, but there was a large number of fibrous tissue and no new bone in controls.</p><p><b>CONCLUSIONS</b>Transplantation of autologous BMMSC with HA-TCP may have therapeutic effect in the treatment of mandibular ORN.</p>

Establishment of a miniature pig model of mandibular osteoradionecrosis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To establish a miniature pig model of mandibular osteoradionecrosis (ORN).</p><p><b>METHODS</b>A single dose of irradiation (IR25 Gy, 28 Gy) was delivered via an electronic linear accelerator to the right mandible of 24 miniature pigs by utilizing three dimensional conformal radiotherapy (3D-CRT). The first molar of the mandible was extracted 2 months after radiation. Mandibular ORN was diagnosed through gross observation, X-ray film, CT, and histopathologic examination.</p><p><b>RESULTS</b>At 3-4 months after radiation, all animals suffered from mandibular ORN after dental extraction. The symptoms of ORN were more severe in the 28 Gy group than in the 25 Gy group.</p><p><b>CONCLUSION</b>A miniature pig model of mandibular ORN can be established through 25 Gy irradiation + dental extraction.</p>

Extraction Process Optimization of Total Flavonoids in Gynostemma Pentaphyllum by Response Surface A-nalysis / 中国药师

Objective:To optimize the extraction process of total flavonoids in Gynostemma pentaphyllum by the method of response surface analysis ( RSM) . Methods: Based on the choice of factors and levels according to the results of single factor test, Box-Be-hnken response surface experiment was designed with the extraction rate of total flavonoids as the index to obtaln the best operation con-ditions and two equations of the response surface model. Results: The optimal extraction conditions of total flavonoids in Gynostemma pentaphyllum were as follows:the volume fraction of ethanol was 71%, the ratio of solid to liquid was 1∶14, and the ultrasonic time was 32 min. Under the conditions, the model predictive value of extraction rate of total flavonoids in Gynostemma pentaphyllum was 4. 676%, and the extraction rate in the verification test was 4. 641%. Conclusion:The fit of the regression model is good, and the ex-traction technology is feasible and reliable.

Influence of aerobic exercise in heart rate variability in obese adolescents / 吉林大学学报(医学版)

Objective To explore the influence of 8-week aerobic exercise in heart rate variability (HRV)in obese adolescents and to provide the evidence for formulating special exercise prescription.Methods Forty male obese adolescents (BMI≥25 kg·m-2 )were randomly divided into exercise group (n=20)and control group (n=20). The subjects in exercise group conducted a 8-week (five times/week,50-60 min)aerobic exercise while those in control group maintained their routine lifestyle. The body composition, hemodynamic parameters including heart rate(HR)and blood pressure and HRV parameters including total power (TP),normalized low frequency (LFn), normalized high frequency (HFn)and LFn/HFn ratio were measured before and after experiment.Results There were no significant differences of the indicators of the subjects between two groups before experiment (P>0.05). At the end of experiment,compared before experiment,the fat mass(FM),the percentage of body fat(BF%), the rest HR,SBP and DBP were decreased (P0.05).Compared control group,the FM,the BF%, the rest HR,SBP,DBP,LFn and LFn/HFn ratio were decreased while the TP and HFn were increased (P<0.01)in exercise group after experiment.Conclusion Aerobic exercise may effectively reduce the sympathetic activity and increase the vagal tone in the obese adolescents.

Transfection and expression of leptin gene in human placental mesenchymal stem cells / 实用口腔医学杂志

Objective:To construct a eukaryotic expression vector of leptin gene,and to transfect it into human placental mesenchy-mal stem cells(HPMSCs)and appraise its expression.Methods:Primers were designed and the leptin gene was obtained by RT-PCR from human adipose tissue.The aimed segments were inserted into the eukaryotic expression vector pIRES2-EGFP,plasmid pIRES2-EGFP-LEP was constructed and identified by restricted enzymatic resection,and then transfected it into HPMSCs by liposome.The ex-pression of leptin in the transfected cells was detected by RT-PCR and Western blotting,the multi-differentiation potential of the cells was indentified.Results:The length of specific fragment was 500 bp,the recombinant plasmid pIRES2-EGFP-LEP presented 5.3 kb and 500 bp bands by restriction enzyme digestion.Leptin gene was expressed in transfected HPMSCs and the transfected HPMSCs maintained multi-directional differentiation potential.Conclusion:The eukaryotic expression vector of leptin can be transfected and ex-pressed in HPMSCs.