Objective:To establish an animal model of bone distraction in the irradiated dog mandible.Methods:1 0 Chinese dogs were used.8 dogs received a unilateral irradiation of 60 Co(Group R)in the mandible with a total dose of 22.8 Gy in four 5.7 Gy frac-tions (biologically equivalent to 50 Gy/25 fractions).The other 2 dogs without irradiation served as the controls(Group C).Bilateral corticotomy was made 3 months after completion of irradiation.After a 1 -week latency period,bone distraction was activated at a rate of 0.5 mm twice daily for 1 0 days,followed by a consolidation phase of 8 weeks.New bone was evaluated by radiographic,histological and single photon emission computed tomography(SPECT)analysis.Results:One dog was excluded from the study due to anaesthetic death in group R.After 8 weeks of consolidation,no difference was found between the percent area of new bone of both groups.New bone was more mature and organized in Group C than that in Group R.SPECT analyses showed that there was active osteogenic activity in Group R.Conclusion:Distraction osteogenesis can be achieved in the irradiated dog mandible.

Objective: To evaluate the corrosion resistance of Ni-Cr alloy with different coatings in neutral and acid saliva by electrochemistry method. Methods: Measured the self-corrosion potential (Ecorr) and polarization resistance(Rp) curves of Ni-Cr alloy models with different coatings in neutral and acid artificial salivas. Results: The Ecorr of the Ni-Cr alloys all showed positive values, the electrochemistry corrosion and galvanic corrosion were not detected. Conclusion: Ni-Cr alloy with titanium nitride coating, gold electroplating coating, gold-paste layer and gold-porcelain blended layer have both anti-corrosion and esthetical function without changing its own property.

OBJECTIVE:To establish a method for simultaneous determination of 5 kinds residual ethanol,acetone,ethylacetate,N,N-diisopropylethylamine and toluene in favipiravir.METHODS:Headspace GC was adopted.The determination was performed on DB-624 capillary column,temperature programmed.The inlet temperature was 220 ℃,and detector was flame ionization detector with temperature of 250 ℃.Nitrogen was used as carrier gas at flow rate of 2.0 mL/min,split ratio was 10 ∶ 1,headspace equilibrium temperature was 80 ℃,equilibrium time was 20 min and headspace sample size was 1 mL.RESULTS:The linear range was 10.0-501.4 μg/mL for ethanol(r=0.999 9),10.0-501.4 μg/mL for acetone (r=0.999 9),10.1-502.6 μg/mL for ethylacetate (r=0.999 9),0.2-11.4 μg/mL for N,N-diisopropylethylamine (r=0.999 9)and 1.8-89.4 μg/mL for acetone(r=0.999 7).The limits of quantification were 5.3,3.4,5.2,6.1 and 20.4 μg/mL,and the limits of detection were 1.4,1.1,1.3,1.6,5.9 μg/mL.RSD of precision test was lower than 4.0％,and RSDs of acetone in stability and reproducibility tests were both lower than 4.0％.The recoveries were 96.61％-99.70％ (RSD=1.01％,n=9),95.81％-99.50％ (RSD=1.29％,n=9),96.42％-99.76％ (RSD=1.24％,n=9),96.36％-99.30％ (RSD=1.19％,n=9),97.00％-99.51％ (RSD=0.82％,n=9).CONCLUSIONS:The method is simple,accurate,reproducible and can be used for simultaneous determination of 5 organic solvents in favipiravir.

OBJECTIVETo investigate the incidence and risk factors for hypertension among taxi drivers working different shifts.

METHODSUsing the cluster sampling method, 415 day-shift and 304 night-shift taxi drivers in Jinan, China were selected and investigated. The influencing factors for hypertension were analyzed.

RESULTSThe incidence of hypertension in all taxi drivers was 33.2%. The incidence of hypertension in night-shift drivers was significantly higher than that in day-shift drivers (37.8% vs 29.9%, P<0.05). According to multivariate analysis, the incidence of hypertension in day-shift drivers was closely related to body mass index (BMI), working years, working hours, sleep duration, rest days, diet quality, water intake, and smoking, while the incidence of hypertension in night-shift drivers was closely related to BMI, working years, working hours, part-time job, sleep duration, rest days, and drinking.

CONCLUSIONBMI, working years, and working hours are the common risk factors for hypertension in day-shift and night-shift drivers. Sleep duration and rest days are the common protective factors. The risk factors for hypertension in taxi drivers vary with different shifts.

Automobile Driving ; Body Mass Index ; China ; epidemiology ; Humans ; Hypertension ; epidemiology ; Incidence ; Occupational Health ; Rest ; Risk Factors ; Time Factors ; Work Schedule Tolerance

A high xylanase producing strain 22 of Aspergillus clavatus was screened from 105 strains of molds and yeasts. The suitable medium consisted of (g/L): bagasse hemicellulose 30, NH_4NO_3 5, yeast extract 5, wheat bran 10, Tween 80 1 and a small quantity of other minerals; initial pH 5.5. Theoptimalsporeinoculumwas4.9X10~6spores/ml (final concentration). Theactivity of xylanase was as high as 335.9 U/ml in shake-flask experiment at 28℃ for 72 h. The optimal temperature and pH for xylanase reaction were 50℃ and pH 4.8. 72.6% of its original activity was remained after incubation at 50℃ for 1 h, and 90% of the enzym activity was observed upon storage at 8℃ for 9 days . Sugars. Na~+. Ca~(2+). and Zn~(2+) increased its activity wherease Co~(2+)and Cu~(2+) inhibited it.

Objective To investigate the effects of ciyelosporine-A(CsA).a calcinenrin(CAN)inhibitor,on electrophysiological propertiesof atria in canine tachycardia-induced model of AF.Methods Eighteen healthy adult mongrel canines weighing 17.0 to 23.2 kg(rangedfrom 2 to 4 years old)were randomized to 3 groups,Sham group(no pacemaker was implanted),atrial tachypacing group(ATP group)each group at baseline and after 8 weeks' tachypacing.Measurements included atrial effective refractory period(AERP),conductionvelocity(CV),wave length(WE),atrial fibrillation load and rate-adaptability. Results After 8 weeks' atrial tachypacing,ATP andCsA groups showed significant longer duration of the P wave,shorter AERP,decreased adaptation of AERE slower CV,shorter Wland longer AF duration compared to the shamg roup (all P＜0.05).AERP of the CsA group was longer than that of ATP group (P＜0.05),but there were no differences in rate-adaptability,CV,incidence of induced AF and AF duration between CsA group and ATP group.Conclusions Our results suggest that calcineurin pathway intervention by CsA have a positive effect on tachycardia-inducedelectrical remodeling of atria,but can not prevent or reverse AF.

Objective To observe the influence of psychological stress and countermeasure implementation upon the temporomandibular joint ( TMJ ) articular disc and external pterygoid muscle in rats,providing experimental and theoretical evidence for clinical treatment of psychological stress-induced temporomandibular disorders (TMD).Methods The animal models treated by psychological stress induced by alternating current box were established.Before and after subjected to psychological stress,rats were given anxiolytic drugs to eliminate stressors.For all the rats in control group,psychological stress group ( PS group),and psychological stress plus anxiolytic drug injection group ( ( PS + DI) group),the microstructure of TMJ articular disc and external pterygoid muscle the changes in RNA expression of interleukin-1 ( 1L-1 ) were investigated by using transmission electron microscope (TEM),scanning electron microscope ( SEM ) and RT-PCR methods,respectively.Statistical analysis was performed upon the obtained test results.Results The TEM showed pathlogical changes in rats'pterygoid muscles of PS group at 1,3 and 5 weeks,including edema,reduction of substrate density and microchondrial cristae.Instead,these structures were all showed normal in the group of PS + DI and recovering group after removal of stressor.For the rats in PS group,SEM observation revealed that partial synovium of articular disc began to disintegrate 1 week after psychological stress.Strip-like wear degenerations were shown in the surface collagenous fiber in articular disc 3 weeks later,and the surface collagenous fibers in articular disc were arrayed in disorder 5 weeks following stress treatment.No significant microstructural changes in articular disc were observed in all stressor-eliminating groups and ( PS + DI) group 1,3,and 5 weeks following stress treatment.Statistical significance was noted in RNA expression level of IL-1 between PS group and PS + DI group (P＜0.05).In addition,there was significant difference in IL-1 expression between PS group and all stressor-eliminating groups.Conclusion The implementation of countermeasures effectively counteracted the influence upon TMJ induced by psychological stress,and provided possible resolutions for the clinical treatment of TMD induced by psychological stress.

Background and Objectives The relationship between left atrial (LA) size and congestive heart failure (CHF) is well recognized;however, there is little information on the association of pulmonary vein (PV) diameter and CHF.The purpose of this study was to investigate the changes of PV and LA sizes in CHF patients by multislice computed tomography (MSCT) angiography using a new 64-slice scanner. Methods and Results We assessed diameters of PVs ostium and LA by 64-slice MSCT with three-dimensional reconstruction in 25 CHF patients and in 26 age- and sex-matched non-CHF controls. Compared with controls, CHF patients showed significant greater diameters of left superior pulmonary vein (LSPV) and right inferior pulmonary vein (RIPV) in both anteriorposterior(AP) and superior-inferior (SI) directions (P＜0.01), significant dilation of right superior pulmonary vein (RSPV) in AP direction (P＜0.05), as well as significant increase of LA transverse, AP, and SI diameters (P＜0.01). Conclusion Significant dilation of PVs with simultaneous LA enlargement was demonstrated in CHF patients. This anatomic and geometric changes may participate in the perpetuation of AF.

Objective To assess the safety and efficacy of a novel biodegradable polymer and rapamycin-coating stent, the EXCEL stent, in the treatment of coronary artery disease (CAD), as compared with the CypherTM stent. Methods In this prospective, non-randomized study, 60 consecutive patients with symptomatic CAD received either an EXCEL stent (n=32), or a CypherTM stent(n=28),according to their respective treatment intention. Follow-up angiography was performed at a mean of 180±40 days. The primary endpoint of the study was the occurrence of a major adverse cardiac event (MACE), including death, myocardial infarction, or target-vessel revascularization during the 6 months after stenting. The secondary end points included the in-stent late luminal loss (LLL), percentage of in-stent stenosis of the luminal diameter, and the rate of restenosis (luminal narrowing of 50 percent or more) at 6 months. Results There were no significant differences between the two groups in baseline characteristics, including the distribution of target vessel and lesion types. During the follow up period of 6 months, there were no occurrences of MACE in either group. Twenty-seven patients(84%) in the EXCEL group and 10 (36 %) in the CypherTM group underwent quantitative coronary angiography at 6 months. For these patients, no restenosis occurred, and there were no differences in the in-stent stenosis of the luminal diameter (5.98±5.52% vs 5.21 ±6.3%,P＞0.05) and the LLL (-0.02±0.09 mm vs -0.01±0.07 mm, P＞0.05). Conclusions Compared with the CypherTM stent, the EXCEL Stent with biodegradable polymer and rapamycin-coating showed similar efficacy in the prevention of neointimal proliferation, restenosis, and associated clinical events in CAD patients.

Objective To screen and verify the proteins interacting with phosphorylation cluster of DNA dependent protein kinase catalytic subunit((DNA-PKcs) by yeast two-hybrid assay.Methods To know the proteins interacting with DNA-PKcs phosphorylation cluster,yeast two-hybrid assay was applied to screen the cDNA library of human hepatic tissue with a previously constructed plasmid pGBKT7-DPC.The positive clones were further identified by PCR,rotary validation and sequence analysis.Then the eukaryotic expression vectors of the bait protein and screened positive clone proteins were constructed and transfected into human embryonic kidney 293T cells to detect whether the proteins could been expressed correctly.At last,the bait protein and screened positive clone proteins were co-transfected into 293T cells and protein interaction was detected with Co-Immunoprecipitation (Co-IP) assay.Results After two rounds of screening using the yeast two-hybrid assay,12 candidate clones were obtained.Then 7 clones with different insert fragments were identified by PCR,and 3 positive proteins interacted with DNA-PKcs phosphorylation cluster were further verified by rotary validation.Sequencing analysis demonstrated that these 3 proteins were MBNL1,SIK2 and YY1AP1,respectively.Accordingly,the eukaryotic expression vectors of bait protein and 3 positive clone proteins were constructed successfully and expressed correctly in 293T ceils.Finally,the Co-IP assay confirmed that these 3 positive clone proteins could interact with DNA-PKcs phosphorylation cluster.Conclusions Proteins interacting with DNA-PKcs phosphorylation cluster are successfully screened and identified.