Vascular construction is an important content in tissue engineering domain,in vitro implanting seed cells on absorbable scaffold materials to form multi-layered cellular layer and establish autoblood vessels along the scaffold absorption. The tissue-engineered vessels are characterized by high biocompatibility and plasticity,less foreign body reaction,and no thrombus production and infection; in addition,the vessels may finally become autoblood vessels in the complete significance. In this article,artificial vascular materials,scaffold processing methods,and vascular culture of seed cells were compared to explore an ideal method to make artificial vessels.

Objective To study the effect of gallamine triethiodide (GT) on the increased afferent discharge from the muscle spindle caused by succinylcholine (SCh). Methods The nervous filaments of rats were separated from tibial nerve innervating the gastrocnemius muscle, and afferent discharge from the muscle spindle was recorded. SCh of a certain dose was injected after 4 minutes of injection of a certain dose of GT. The effect of suppression by GT on the increased afferent discharge from the muscle spindle caused by SCh was measured by counting the decrease in discharge peak frequency (DPF) and maximum increase frequency (MIF) and by counting the time of peak frequency (PF) appearing delayed than the controls. Results When the dose of SCh was 0.005mmol/kg, the dose of GT was 0.005mmol/kg, 0.010mmol/kg and 0.020mmol/kg, DPF reduced to 67.2%, 52.5% and 37.1% of the controls, respectively; MIF reduced to 61.4%, 40.2.% and 25.4%; PF appearing time delayed 43.9s, 64.3s and 80.4s than the controls. When the dose of GT was 0.005mmol/kg but the dose of SCh was 0.010mmol/kg, DPF and MIF reduced to 83.3% and 77.8% of the controls, respectively; PF appearing time delayed 22.5s than the controls. Conclusion GT has a remarkably suppressive effect on the increase in afferent discharge from the muscle spindle induced by SCh. The suppression of GT is dose-dependent, and the action of SCh and GT on muscle spindle is in competition.

ObjectiveTo study wether muscle spindle afferents have the regulating effects on res piratory movement. MethodsExperiments were performed on 36 anesthetized, immobilized, bilater ally vagotomized and artificially ventilated rabbits. Using the phrenic nerve discharge as the respira tory index, this experiment have assessed the effects of muscle spindle afferents invoked by intraarte rial injection of succinylcholine(Sch) on respiration. Results①In 40(63.49% ) cases which had the facilitated effects, 23 (36.51%) cases had the effect of prolonged inspiratory phase and 17 (26.98 % ) cases had the effect of attenuated expiratory phase and augmented respiratory frequency. In addition,there were 11(17.46% ) cases which had the attenuated effects,and 4(6.35% ) cases which had the biphasic effects,and 8(12.7% ) cases which had no effects;②The effect of prolonged inspiratory phase mainly showed the prolongation of inspiratory duration(Ti), but the effect of at tenuated expiratory phase and augmented respiratory frequency mainly showed the decrease of expi ratory duration (Te) and the augmentation of respiratory frequency(RF) ;③The above facilitated ef fects of Sch were significantly attenuated by intramuscular application of bupivacaine to destroy the muscle spindles. ConclusionThese results suggest that muscle spindle afferents induced by intraar terial injection Sch have a significant facilitated effect on respiration.

The effects of spindle afferents activated by stretching gastrocnemius on the nociceptive responses of WDR neurons were recorded extracellularly with microelectrode and observed in paralyzed rats. The results indicated that in 51/80, the spindle afferent activity activated by stretching can inhibit nociceptive responses of neurons. 16 out of 80 neurons no effects can be observed, in 13/80 the effects of spindle afferent activity can excite the nociceptive responses of WDR neurons. Among 51 units, which have inhibitory effects induced by stretching muscle, the inhibitory effects induced by instance and bilateral stretching are stronger than that induced by continuous and unilateral stretching. These results suggested that spindle afferent activity is possesaed of analgesic effects.

Objective To understand the situation of indoor air fluoride and arsenic pollution caused by coal-burning and the impact of the pollution on children health in the rural area,southern Shaanxi Province.Method 77 fluoride samples and 186 arsenic samples were collected in 65 investigated villages of 5 counties in southern Shaanxi Province.13 120 children aged 8-12 years were selected for dental fluorosis examination,13 386 children aged 6-18 years for arsenism examination.Results Both of the average content of fluoride and arsenic in the indoor air exceeded the national standard limit.Fluorine content was 0.001-0.541 mg/m3 with an average of 0.038 4 mg/m3,arsenic content was 0.00-63.83 ?g/m3 with an average of 4.76 ?g/m3.The prevalence rates of dental fluorosis and arsenism were 45.50% and 1.86% respectively.Conclusion The indoor air fluoride and arsenic pollution caused by coal-burning in the investigated rural area is serious and the pollution has caused the prevalence of endemic fluorosis and endemic arsenism among the local children.

Objective To master the running conditions of water project and the defluoridation results in monitoring sites of drink-water type fluorosis in Shaanxi Province,to provide a scientific basis of preventing and controlling endemic fluoroisis. Methods Every April and September 1998—2005 children aged 8～12 at school from the two monitoring sites of Wupo and Bayi village received the dental fluorosis examination by using the Deans method.The urine samples of 50 children from 5 age groups who were selected randomly and were grouped in 5 with 10 children each were collected,measured in accordance with WS/T 89—1996 Determination of Fluoride in Urinlon Selective Electrode Method,evaluated by Manual of Endemic Fluorosis Control(1991). At least 5 water samples were collected randomly from five directions(east,west,north,south,center).The fluoride contents in urine and drinking water were determined with FSIE,in accordance with GB/T 5750--2006 Standard Examination Methods for Drinking Water,evaluated by GB 5749—2006 Standards for Drinking Water Quality.Results After changing water,morbidity rate of children dental fluorosis fell from 66.67%in 1998 to 31.79%in 2005 and the dental fluorosis index also fell form 1.49 to 0.65 of Wupo village,morbidity rate of children dental fluorosis fell from 33.15%in 1998 to 13.10%in 2005 and the dental fluorosis index also fell from 0.50 to 0.24 of Bayi village.The fluoride contents in urine of children and the fluoride contents in drinking water were maintained stability.Conclusion After water improvement,the fluorosis has been effectively controlled in a certain degree in the investigated area.

Objective To study the effects of RNA interference(RNAi)-mediated silencing of mitofusin-2 (Mfn2) gene on glycornetabolism and insulin resistance in BALB/c mice. Methods Mfn2 short hairpin RNA (shRNA) and negative control green fluorescent protein(GFP) -expressed plasmid vectors were constructed. 44 mice were randomly divided into transfection group (Mfn2) and negative control group (HK). 1.5 ml GFP-expressed plasmid(negative control or Mfn2 shRNA,75 μg for each mouse)was injected into the mice in 5 seconds through vena caudalis. Five days later, intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test(IPITT)were performed to evaluate glycometabolism and insulin sensitivity. D-3-[3~H]-glucose in PBS buffer were injected via the tail vein. Blood samples were taken at specific time points. Radioactivity was measured in all samples with liquid scintillation counter. The rates of hepatic glucose production in vivo were calculated. Mfn2 protein expression in hepatic tissue was detected by Western blot. Results Compared with HK mice, the Mfn2 expressions of Mfn2 mice decreased markedly(8.05±0.15 vs 8.56±0.01 ,P<0.05). The fasted blood glucose leves [(6.95±0. 83 vs 4.68±0. 29) mmol/L,P<0. 05] in Mfn2 mice were higher than those in HK mice. The insulin sensitivity of Mfn2 mice decreased markedly compared with HK mice. The rate of hepatic glucose production was significantly elevated in Mfn2 mice [(49.53±16.31)μmol·kg~(-1)·min~(-1)],compared with negative control mice[(24.91±4.07)μmol·kg~(-1)·min~(-1),P<0.05].Conclusion The down-regulatd expression of Mfn2 induces glycometabolic disorder and insulin resistance in BALB/c mice. Mfn2 plays an important role in maintaining glucose homeostasis in vivo.

ObjectiveTo investigate the role of NRM in the antinociceptive effect of muscle spindle afferents, the influence of NRM lesion on the inhibitory effect of muscle spindle afferents on the nociceptive responses of wide dynamic range (WDR) neurons and the effects of the muscle spindle afferents on the NRM neuronal activities were observed. MethodsThe single units of WDR neurons in the spinal dorsal horn were recorded extracellularly, and the inhibitory effects of activating muscle spindle afferents by intravenous administration of succinyicholine (SCH) on the C-fibers evoked responses (C-responses) of WDR neurons were tested before and after lesion of NRM. The ef- fects of the muscle spindle afferents activated by administrating SCH on the single NRM neurons were also examined. Results①lt was found that the C-responses of WDR neurons were significantly inhibited by intravenously adminis- tration of SCH, and the inhibitory effect was reduced after lesion of NRM ;②The activities of most of the NRM neu- rons could be changed significantly by administrating SCH. According to their responses, NRM neurons could be classified into three types:excitatory, inhibitory and non-responsive neurons, and the responses were dose-depen- dent. ConclusionThese results suggest that the muscle spindle afferents evoked by SCH may activate the NRM neu- rons, which plays an important role in the antinociception of muscle spindle afferents.

Objective To investigate the characteristic and clinical value of echocardiography in pregnant women with sinus tachycardia.Methods Thirty pregnant women with sinus tachycardia (experiment group) and 30 healthy pregnant women (control group) were selected.The echocardiography results and clinical data were compared between the 2 groups.Results There were no statistical differences in age,gestational age,blood pressure,weight between the 2 groups (P ＞ 0.05).The heart rate in experiment group was significantly higher than that in control group [(123.20 ± 13.23) times/min vs.(86.17 ± 6.78) times/min],there was statistical difference (P ＜ 0.01).The left ventricular posterior wall thickness and the rates of mitral regurgitation,tricuspid regurgitation,aortic regurgitation in experiment group were significantly higher than those in control group [(10.23 ± 1.30) mm vs.(8.79 ± 1.90) mm,63.33％ (19/30) vs.16.67％ (5/30),66.67％(20/30) vs.30.00％(9/30),26.67％(8/30) vs.6.67％(2/30)],the left ventricular posterior wall motion amplitude was significantly lower than that in control group [(8.07 ± 1.00) mm vs.(9.26 ± 1.71) mm],there were statistical differences (P ＜ 0.01 or ＜ 0.05).There were statistical differences in the indexes of left ventricular systolic function and diastolic function between the 2 groups (P ＜0.01 or ＜0.05).Conclusion The anatomical indexes and function indexes of echocardiography in pregnant women with sinus tachycardia are used to change,and the echocardiography in time can provide the basis of treatment.

Objective To study Tephroseris Kirilowii Turez.Houlub extract on cell cycle and apoptosis marker AnnexinV/PI of U266 in vitro..Methods U266 cells were cultured together with Tephroseris Kirilowii Turez.Houlub extract.Cell cycle and apoptosis marker AnnexinV/PI were detected by flow cytometry(FCM).Results After exposure of U266 cells to Tephroseris Kirilowii Turez.Houlub extract.the cell cycle distribution was changed.There Was a decrease of cells in the G0/G1 phase with an increase of cells in the S phase and G2/M phase and apoptosis.FCM with staining of Annexix V FITC/PI showed a dependence of apoptotic cells with the dosage of Tephroseris Kirilowii Turez.Houlub extract.Conclusion Tephroseris Kirilowii Turez extract has strong cell apoptosis effect on U266 cells.