BACKGROUND:Bioactive glass has good biocompatibility, which can promote the remineralization effects of demineralized enamel and enhance the resistance of enamel to erosion. OBJECTIVE:To evaluate the effect of bioactive glass toothpaste versus fluoride toothpaste on brushing abrasion of enamel after acid etching. METHODS:Fifty-six enamel specimens were prepared from bovine incisors, and were embedded in acrylic resin with exposed buccal surface. The exposed area was 6 mm×6 mm and two amalgam fil ings were placed into the enamel and polished. Al specimens were divided into seven groups with eight specimens each. In six groups, specimens were brushed with ordinary toothpaste, fluoride toothpaste, bioactive glass toothpaste immediately and 30 minutes after being eroded by the Sprite. The last one group was brushed with ordinary toothpaste without acid etching as control. The treatment course was cycled 60 times. The surface abrasion loss of the specimens between two amalgam fil ings compared with respective amalgam reference surfaces was final y observed and calculated under laser scanning confocal microscope. RESULTS AND CONCLUSION:The abrasion loss amount of teeth with no acid etching was significantly lower than that with acid etching (P<0.05). The abrasion loss amount of teeth brushed with bioactive glass toothpaste was less than that with fluoride toothpaste at the same brushing time (P<0.05). For the same toothpaste, the abrasion loss amount of teeth brushed 30 minutes after eroded was less than that bushed instantly after eroded (P<0.05). Use of bioactive glass toothpaste can effectively reduce enamel loss caused by acid etching and brushing. The loss amount can also be reduced by brushing teeth 30 minutes after acid etching.

Objective To detect clopidogrel effect with light transmission aggregometry (LTA)and flow cytometry (FC). Methods ①Venous blood samples were taken from 71 inpatient with acute corotary syndrome (ACS)in PLA General Hos-pital,including unstable anqina,ST segment elevation myocardial infarction and non ST segment elevation myocardial infarc-tion (46 males,25 females)by random number table from June 2011 to March 2012,whose average age was 69(57~92).②All of them were served 160 mg aspirin and 300 mg clopidogrel after they were in hospital in the beginning,and then served with 75 mg/d clopidogrel for 6 months.On some day,firstly,they were required withdrawing drug for 10 days,and then ve-nous blood samples were separately taken from them before their served-clopidogrel again and their severd-clopidogrel 2 hours later.③The samples were assayed with LTA and FC simultaneously and the platelet aggregation rates before served-clopidogrel (ADPLTA-before serving ),platelet aggregation rates after served-clopidogrel (ADPLTA-after serving ),inhibition rates (ADPLTA-INDU ),PAC-1 activity percentage before served-clopidogrel (PAC-1 before serving ),PAC-1 activity percentage after served-clopidogrel (PAC-1 after serving ),inhibition rates (PAC-1 INHI ),CD62p activity percentage before served-clopidogrel (CD62pbefore serving ),CD62pactivity percentage after served-clopidogrel (CD62pafter serving ),inhibition rates (CD62pINHI )weregotten.All volunteers were signed informed consents and the experiment was approved by the hospital ethics committee.Re-sults ①The paired samples t-test was (t=-2.082,P =0.041)between ADPLTA-before serving (0%~97%)and ADPLTA-after serving (12%~97%),the paired samples t-test was (t = 3.663,P < 0.01)between PAC-1 before serving (15.1% ~ 78.9%)and PAC-1 after serving (14.5% ~ 78.3%);the paired samples t-test was (t = 2.082 and P = 0.041)between CD62pbefore serving (1.5% ~80.8%)and CD62pafter serving (1.4%~41.4%).②The pearson coeffcient correlation results were:ADPLTA-INDU (0%~28.2%) and PAC-1 INHI (0.6%~ 9.1%)(r = 0.297,P = 0.012);ADPLTA-INDU (0% ~ 28.2%)and CD62pINHI (0.1% ~ 48.5%)(r =0.220,P =0.065);PAC-1 INHI (0.6%~9.1%)and CD62pINHI (0.1%~48.5%)(r=0.736,P <0.001).Conclusion Because the correlation was bad between the inhibition rates of clopidogrel detected by FC and them by LTA,FC didn’t apply to clin-ical routine examination of the platelet aggregation.But it could be used to scientific researchs and auxiliary confirmation of routine examination results.

BACKGROUND: Three-dimensional printing technology is a new technology which can quickly and accurately transform the virtual computer-aided design into the three-dimensional physical prototypes. Three-dimensional printing physical model method can replace the method of traditional preoperative planning and repair surgical simulation, with the characteristic of repeatable, which has been deepened day after day in clinical application of spine surgery. OBJECTIVE: To summarize the application status of three-dimensional printing technology in spine surgery and look forward to its future development directions. METHODS: The articles regarding the application of three-dimensional printing technology on clinical applications in spine surgery were retrieved from PubMed databases, Google Scholar, China National Knowledge Infrastructure and Wanfang Database from January 2000 to July 2015. The key words were 3D printing technology, rapid prototyping technology, spine, vertebra, department of orthopedics, fracture, joint, hand and foot, bone tumor, trauma, cervical vertebrae, thoracic vertebrae, lumbar vertebrae, sacral vertebrae, pedicle of vertebral arch, vertebral body, intervertebral disc, and clinical application. A total of 50 articles with a good representation were selected and discussed after repetitive studies and reviews were excluded. RESULTS AND CONCLUSION: The three-dimensional printing technique has been applied in preoperative diagnosis, individualized orthosis customerization, the communication between doctors and patients, teaching, the formulation of individualized and high-accurate repairing plan, intraoperative navigation and individualized implant customization. These results suggest that with the rapid development of medical imaging, digital medicine and technologies of the cel and tissue culture and new materials, three-dimensional printing technology wil have a wide range of applications in spine surgery.

Objective To observe the clinical effects of chimney technique combined with thoracic endovascular aortic repair(TEVAR) in the treatment of type B aortic dissection.Methods The clinical datas of 56 patients with type B aortic dissection in our hospital were analyzed retrospectively.According to the surgical intervention method,they were divided into observation group (22 cases,TEVAR + chimney technique) and control group (34 cases,TEVAR alone).Surgery related indicators,incidence of postoperative short-term complications and mortality between the two groups were compared.Results The success rates in both groups were 100％,and the surgical time in observation group was longer than that in control group (P ＜ 0.05).There were no significant differences in blood loss,eating time,off-bed time and hospitalization time between the two groups(P ＞ 0.05).The incidence of complications of observation group and control group within 2 weeks after operation were 18.2％ and 5.8 ％ respectively,the difference was not significant(P ＞ 0.05),as well as mortality and incidence of longterm complications during the followed period (P ＞ 0.05).Conclusion The perioperative indexes of single endovascular repair and its combination with chimney technique for the treatment of type B aortic dissection are similar.Chimney technique can reconstruct important branch flows,especially for patients with insufficiency of landing zone.However,particular attention needs to be paid to postoperative complications to avoid negative effect on the prognosis of patients.

Through analyses of rare diseases management of several countries and regions , successful practice has been discussed .Legislation of rare diseases should be activated as soon as possible to release specific standard of rare diseases .Accelerating development of translational medicine is a feasible approach to improve the level of diag -nosis and treatment of rare diseases .Strengthening the orientation of management policy should be put into a more significant position to promote incentives of stakeholder in this area .Both enhancing the joint collaboration of differ-ent departments and perfecting medical insurance system could be forceful accelerants to create and optimize the management system of rare diseases in China .

Forty one patients with esophageal carcinoma (T3N1 M0 or less) underwent video-assisted thoracoscopic surgery (VATS) in prone position for esophagectomy from September 2006 to September 2010.The postoperative outcome and survival of patients were retrospectively analyzed.The results confirmed the feasibility and safety of this minimally invasive esophagectomy performed by thoracoscopy in the prone position for patients with esophageal carcinoma.

Thirty-three patients with esophageal carcinoma (T3N1M0 or less) underwent thoracoscopic surgery in lateral prone position for esophagectomy from February 2010 to November 2012.Their postoperative outcomes and survivals were retrospectively analyzed.The results confirmed the feasibility and safety of this mini-invasive thoracoscopic procedure in lateral prone position for patients with esophageal carcinoma.A possible advantage of lateral prone technique is that in case of an emergency switch to open surgery,precious time may be saved in changing body position.

BACKGROUND:Pathological mechanism of femoral head necrosis is not fuly known, and high-dose corticosteroids are prone to induce femoral head necrosis.
OBJECTIVE:To investigate the clinical effect of bone marrow mesenchymal stem cels combined with theaflavin on steroid-induced avascular necrosis of femoral head in rats.
METHODS: Rat bone marrow mesenchymal stem cels were isolated and culturedin vitro and compounded onto gelatin sponge, and then, divided into four groups: model group, decompression group, cel transplantation group and combined group. Models of steroid-induced avascular necrosis of femoral head were established using liquid nitrogen method. In the combined group, gelatin sponge carrying bone marrow mesenchymal stem cels was transplanted and 250 mg theaflavin was given daily after modeling.
RESULTS AND CONCLUSION:At 4 weeks after modeling, the femoral head samples in the four groups were round with exfoliation of articular cartilage that was pale in color. Then, the exfoliation of articular cartilage was aggravated in the model group, and some specimens appeared to colapse; the femoral head specimens in the combined group were round and pale. Until the 8th week after modeling, bone necrosis was increased in the model group; osteoblasts were found in the decompression group with fibrous calus formation; a few of empty bone lacunae appeared with irregular medulary cavity in the cel transplantation group; a large amount of new bone tissues formed in the combined group, and intramedulary adiocytes were in regular array. At 4 and 8 weeks after modeling, the number of empty bone lacunae was significantly lower in the combined group than the other groups (P < 0.05). These findings indicate that bone marrow mesenchymal stem cels combined with theaflavin is an ideal therapy for steroid-induced avascular necrosis of femoral head.

Objective To use three different methods in attempt to estimate the biological dose of the patient partially exposed to 192Ir source at5.7 accident in Nanjing,so as to provide dosimetric information for clinical remedy of exposed patients in the emergency of a nuclear accident.Methods Peripheral blood samples were collected on days 5 after exposure.The biological dose was estimated by the yields of dicentrics plus rings ( dic + r),cytokinesis-block micronuclei (CBMN) assay and nucleoplasmic bridge plus FHC (NPB + FHC).The homogeneity of radiation exposure was examined by Poisson distribution of dicentrics.Results By using three different methods,the whole body equivalent dose was dic + r estimated to be 1.51 Gy (95％ CI 1.40-1.61),1.47 Gy (95％ CI 1.36-1.60) by CBMN and 1.30 Gy (95％ CI 1.00-1.60) by NPB + FHC,respectively.A non-poisson distribution was also detected,suggesting partial body radiation exposure.Conclusions The estimated whole body equivalent dose ot a non-uniform radiation exposure was consistent with clinical diagnosis,suggesting that the yields ofdic + r,CBMN,as well as NPB + FHC,are efficient approaches to the estimation of biological doses.

Objective To explore the natural attenuation pattern of three biological dose estimation indexes in vivo by investigating the effect on biological dosimetry of peripheral blood sampling at different time points from the victim partially exposed to 192Ir radiation source at5.7 accident in Nanjing.Methods Peripheral blood of the patient was collected on days 5,40 and 280 after exposure,respectively.The yields of dicentrics plus rings chromosomes (dic + r),cytokinesis-block micronuclei (CBMN) and nucleoplasmic bridge + fusion + horse shoe + circular(NPB + FHC) were analyzed.The dynamic reduction and dose estimation were both observed using the biomarkers mentioned above after exposure.Results Compared to the estimates on days 5 after exposure,the dose values estimated on days 40 and 280 decreased by 34％ and 49％ fordic + r method,48％ and 79％ for the CBMN assay,and 48％ and 75％ for NPN + FHC method,respectively.Conclusions Three biological dose estimation indexes show a progressive decrease in vivo,with the half-life of dic + r/cell being 40 days.The doses estimated using these three indexes on days 40 after exposure showed a relative deviation more than 20％ compared with those on days 5 after exposure.