BACKGROUND:With increasing freeze-drying time,the water content of allogeneic bone reduces along with the bone mechanical strength.The suitable dehydration degree that maintains mechanical strength of allogeneic bone and allows long-term preservation at room temperature remains controversial.OBJECTIVE:To detect the mechanical properties of bovine bone nail following different degrees of dehydration using the three-point bending mechanics tests.DESIGN,TIME AND SETTING:Biomechanical analysis,comparative observation.The experiment was performed at the Mechanical Laboratory of Southern Medical University between May 2007 and May 2008.MATERIALS:Bone nails,50 mm length and 3 mm diameter,made from healthy adult bovine femoral cortical bone were divided into control and freeze-drying groups (8,12,24 hours,respectively) with 20 samples in each group.METHODS:The water content of bone nails with or without freeze-drying was measured by SH10A Moisture Quick Determination Meter.Three-point bending mechanics tests were performed using MTS 858 Mini Bionix.The parameters included load range 0-2000 N,resolution 0.01 N,cross beam replacement resolution 0.001 mm,span 50 mm and loading speed (cross beam replacement speed) 2 mm/min.MAIN OUTCOME MEASURES:Water content,maximal load and elasticity load.RESULTS:The water content of control group was 7%-9%,and following freeze-drying for 8 hours,the water content was 5.5%-6%,which met the standard of freeze-drying bone;Compared with control group,the maximal load and elasticity load reduced respectively 0.004% and 0.000 8% (P＞0.05).Following freeze-drying for 12 and 24 hours,the water content was 3.5%-4% and 1%-1.5%;the maximal load reduced 21% and 37% and the elasticity load reduced 22.5% and 39% compared with control group (P＜0.05).CONCLUSION:Freeze-drying for 8 hours is the best time of dehydration.The mechanical load and elastic modulus reduce with increasing freeze-drying time.

ObjectiveTo observe the efficacy and safety of house dust mite vaccine in the treatment of house dust mite-allergic rhinitis.Methods47 patients with allergic rhinitis were recruited into the study.The course of SIT was treated by house dust mite vaccine for 51 weeks.Self-contrast method was used to compare the symptom score,nasal airway resistance before and after treatment.Then we observed the security in the process of injection.ResultsThe symptom score was (7.40 ± 1.64) vs ( 3.40 ± 1.50 ) pre and post therapy.Nasal airway resistance were (2.02 ±0.72) vs ( 1.06 ± 0.81 ) kPa · s -1 · L-1.Both the values of the data had significant differences( t =15.49,4.44,all P ＜ 0.01 ).No serious adverse reaction was observed.ConclusionSIT was able to improve the clinical symptoms and decrease nasal airway resistance.House dust mite vaccine was an effect and safe drug for the dust mite allergic asthma patients.

Objective To investigate the effects of hyperoxic-hyperosmotic sodium chloride solution(HHSCS) on arterial blood gas and blood lactate in rabbits with hemorrhagic shock, and evaluate the HHSCS effects on hemorrhagic shock resuscitation.Methods Hemorrhagic shock models were induced in 30 male rabbits.The median arterial pressure(MAP) was declined to 40mmHg within 10 minutes,then maintained for 60(minutes).The animals were then randomly divided into 3 groups:normal saline hyperoxic solution(NSO)group,hyperosmotic sodium chloride solution(HS)group and HHSCS group.Sixty minutes later,NSO,HS or HHSCS 6ml/kg was infused intravenously in 5 minutes.Heart rate(HR) 、respiratory rate(RR)、 MAP and urine drops(UD) before shock and after fluid infusion were recorded;blood lactate(BL) and blood gas were measured before shock,60min after shock,and 30min,60min,120min postinfusion.Finally,the(rabbits) were killed by bleeding,the lungs were observed in autopsy,and the lung coefficient was measured.Results HS and HHSCS more effectively raised MAP,enhanced heart function,and increased UD than NSO.HHSCS group significantly reduced BL.At 60,120min after infusion,SaO_2 in HHSCS group was(significantly) higher than that in HS group and NSO group(P

Objective To explore the effect of lead acetate on the growth of murine mesenchymal stem cells in vitro.Methods 40.00,60.00 and 100.00 ?mol?L-1 of lead acetate were used in the culture of colony-forming unit-fibroblast(CFU-F),the effect on the rate of colony-forming and the rule of variation were observed.Results The rates of colony-forming were(3.30?0.20),(2.40?0.10) and(1.57?0.21)/105,when the doses of lead acetate were 40.00,60.00 and 100.00 ?mol?L-1 and there were significant differences compared with control group(4.20?0.20)/105,P

Objective: To investigate the change and effect of sIL-2R and TNF-α in the immunopathogenesis of experimental allergic encephalomyelitis(EAE). Methods: The EAE model was induced in guinea pigs. And the EAE animals were killed on the 8th, 15th and 22nd day after the MBP+CFA challenge. ConA-treated guinea pig spleen cells were cultured and supernatants were collected. The level of sIL-2R in supernatant was detected by ELISA, and the level of TNF-α in EAE was examined by biologic assay. Results: The EAE animals showed higher levels of sIL-2R and TNF-α than those of the normal control group. Conclusion: sIL-2R and TNF-α play an important role in the immunopathogenesis of EAE. This experiment offered thoretical evidence for further study of multiple sclerosis(MS) on pathogenesis and gave the clues for clinical use of immunospecific agents on MS.

Objective:To generate Epstein-Barr virus(EBV) Latent Membrane Protein 2A(LMP2A) recombinant adenovirus,and provide for further investigation on the therapy vaccine against EBV associated malignancies.Methods:Full length cDNA of encoding LMP2A of EBV had been amplified by reverse transcription-PCR and cloned into pGEM-T vector.The encoding cDNA of LMP2A was inserted into E1,E3-substituted adenovirus vector pAX1CW,then the LMP2A recombinant adenovirus vector was contransfected into 293 cells togetherwith EcoT221 digested Ad5-TPC.The LMP2A recombinant adenovirus was generated by homologous recombination,and primarily identificated by ClaI enzyme digestion.The expression of LMP2A on CV1 cells infected with recombinant adenovirus analyzed by fluorescence-activated cell sorting(FACS) and confocal microscope.Results:The replication-deficient LMP2A recombinant adenovirus was generated efficiently with the titers of 2.3?10 8 pfu/ml.The LMP2A could be seen on CV1 cells membrane with confocal microscope 48 h post infected with recombinant adenovirus and the percentage of CV1 cells expressing LMP2A was 94.4% by means of FACS analysis.Conclusion:These suggested that LMP2A could be expressed efficiently by recombinant adenovirus mediated transfer,and it was the foundation of further researching in its function and developing the suitable genetic engineering vaccine against EBV associated malignancies.

Objective To investigate the physiological responses of healthy youth to doing chest compression as a feedback of quality of CPR after their rapid ascent to high altitude and to evaluate the feedback in the intervention effects of CPR.Methods Prospective,single sample,before-after comparison method was used in this study.Fifteen young adults from plains natives were enrolled as trial subjects in this study.All of them received basic life support training course in advance.In Chongqing (259 m above sea level),subjects performed empiric chest compressions on the model body for 4 minutes followed by feedback compressions for 4 minutes after at least 30 minutes rest.Compression depth,rate and other compression quality parameters were measured and recorded at each turn of compressions with an AED PLUS device.Subjects performed empiric compressions based on their knowledge and experiences,and practiced feedback compressions according to the audiovisual guidance of AED PLUS device.Blood pressure,heart rate and SpO2 were taken before and after each turn of compressions.One week after arrival to Lhasa (3658 m above sea level) by flight,all subjects were asked to do the same procedure as did in Chongqing to see their physiological response to.Paired t tests or Wilcoxon matched pair rank test were used for comparisons of measurements before and after trials.Results Systolic pressures,diastolic pressures,heart rates at baseline in Lhasa were significant different from those in Chongqing,including systolic pressure (125.9 ±9.5) mmHg vs.(112.7 ±13.4) mmHg,diastolic pressure (75.3 ±7.7) mmHg vs.(64.2 ±7.3) mmHg,heart rate (86.3 ± 13.0) beat/min vs.(72.7 ± 11.6) beat/min,SpO2 (90.4 ± 1.7)％ vs.(97.8 ±0.9)％,all P ＜ 0.01.In Lhasa,empiric compressions only caused an increase in heart rate (91.1 ± 14.9) beat/min vs.(86.3 ± 13.0) beat/min,P ＜ 0.01.However,feedback compressions resulted in a significant decrease in SpO2 [(88.3 ± 3.4) ％ vs.(90.6 ± 1.9) ％,P ＜ 0.01] as well as change of systolic pressure [(130.9 ± 11.7) mmHg vs.(120.1 ± 11.9) mmHg,P ＜0.05] and heart rate [(87.9 ± 17.5) beat/min vs.(80.9 ± 11.7) beat/min,P ＜0.05].In Lhasa,the compression quality during feedback compressions was closer to guideline recommendation than that during empiric compressions.The median (interquartile range) of composite qualification rate was 43.6％ (55.9％) vs.0.6％ (5.3％) during feedback compressions and empiric compressions respectively,P ＜ 0.01.Conclusions Compression quality decreased significantly among youth after rapid ascent to high altitude.Feedback techniques for CPR could effectively guide the rescuer to improve their CPR quality,but it may be at the expense of more physical consumption.

Objective To explore the feasibility of mouse muscle-derived cells with adenovirus-mediated expression of BMP-2 in the treatment of mouse tibia bone defect via collagen sponge as scaffold. Methods Mouse adenovirus BMP-2 plasmids were prepared and identified by PCR.The adherent cells of muscle-derived stem cells cultured in vitro were passaged,cells of the third generation were selected,and recombinant Ad-BMP-2 plasmids were expressed and incubated in mouse myoblasts.The number of BMP-2 positive cells was measured using indirect immunofluorescence method,and alkaline phosphatase(ALP) method was adopted to determine the cell activity in each group.The mouse models of proximal tibial bone defect were established(n=80) and were divided into Ad-BMP-2 transfection group,Ad-LacZ transfection group,blank group and Ad-BMP-2 implantation group.The histological and radiological changes were observed 3 weeks after operation. Results It was revealed by indirect immunofluorescence that BMP-2 positive cells were frequently found in Ad-BMP-2 transfection group,while none were observed in Ad-LacZ transfection group and blank group.The ALP activity was higher in Ad-BMP-2 transfection group,while that was extremely low in Ad-LacZ transfection group and blank group.There was most typical imaging of repair and healing of bone defect in Ad-BMP-2 transfection group,followed by Ad-BMP-2 implantation group,while there was no typical imaging in Ad-LacZ transfection group and blank group. Conclusion The constructed Ad-BMP-2 plasmids can effectively transfect mouse muscle-derived cells,and the transfected cells can continuously express effective amount of BMP-2.The mouse muscle-derived cells with adenovirus-mediated expression of BMP-2 play a definite role in the treatment of bone defect,which provides an effective method and material for clinical application.

Object: To investigate the protective effect of Qizhi hypoglycemic tablets on eye diseases in strepto- zotocin-induced diabetic rats and explore its possible mechanism. Methods: Streptozotocin was used to prepare diabetic model in rats. The diabetic model rats were given Qizhi hypoglycemic tablets(780 mg/kg),metformin hydrochloride tab- lets(200 mg/kg)or glibenclamide tablets(1.5 mg/kg)via intragastric administration once a day for three months,and the dynamic changes in eye diseases were investigated. The examined index included blood glucose level,lens opacity, serum levels of aspartate aminotransferase(AST)and alanine aminotransferase(ALT),retina expression of collagen, matrix metalloproteinase-2(MMP-2)and tissue inhibitor of matrix metalloproteinase-1(TIMP-1). Network pharmacology was used to analyze protective mechanism. Results: Compared with the normal group,the model rats showed significant hyperglycemia(P<0.01),polydipsia,polyphagia and polyuria(P<0.01)as well as the decreased body mass(P<0.01), increased serum ALT and AST level(P<0.01),decreased the retinal Collagenexpression(P<0.01),decreased: TIMP-1(P<0.01)and increased lens opacity(P<0.01). Compared with the model group,metformin hydrochloride tab- lets and glibenclamide tablets could improve hyperglycemia(P<0.01),polyphagy,polyuria and emaciation(P<0.01), but had no significant effect on the degree of retinal turbidity(P>0.05). Compared with the model group,Qizhi hypogly- cemic tablets also had hypoglycemic effect(P<0.05),which could improve hyperglycemia,polyuria and emaciation (P<0.01),significantly reduce the degree of retinal turbidity(P<0.01)and up-regulate the expression of retinal Colla- genand TIMP-1(P<0.01). According to the network pharmacology analysis,Qizhi hypoglycemic tablets could regu- late the cell proliferation and apoptosis via VEGF and MAPK signals. Conclusion: Qizhi hypoglycemic tablets could im- prove the ophthalmic disease in diabetic rats,which might be a promising medicine for the treatment of diabetic ophthal- mic disease.

Hepatocellular carcinoma (HCC) is a serious threat for human health, the incidence of HCC in China accounts for more than 50% worldwide. There is an urgent need to develop novel anticancer agents for the treatment of HCC patients. Here we characterized the inhibitory effect and the molecular mechanism of protopine on HCC cancer cells. The results of a CCK-8 assay indicated that protopine displays anticancer activities on HCC cells. Flow cytometry and JC-1 staining confirmed that treatment with protopine decreased the mitochondrial membrane potential and induced apoptosis in HCC cells. Western blot analysis showed that protopine was able to increase protein expression in the mitochondrial apoptotic pathway; the level of cytochrome C, apoptotic protease activating factor-1 (Apaf-1), Bax, cleaved-poly ADP-ribose polymerase (cleaved-PARP), cleaved-caspase-3, and cleaved-caspase-9 were increased while the expression of Bcl-2 was suppressed significantly. An in vivo study revealed that protopine significantly suppressed the growth of tumors in nude mice bearing HepG2 cells. Administration of protopine intraperitoneally at a concentration of 50 mg·kg^-1 inhibited tumor growth by 72.46%. Animal experiments were carried out according to the Regulation of the Animal Ethics Committee of Southwest Medical University. This study provides preliminary evidence that there is potential to develop protopine as a lead compound for the treatment of HCC.