Objective To study the effects of strontium (Sr) on proliferation and osteogenic differentiation of human marrow mesenchymal stem cells (hMSCs) in vitro,and to determine its optimal concentration.Methods Six milliliter of bone marrow was obtained from a healthy adult volunteer,the hMSCs were then isolated and cultured in vitro,and the cell phenotype was identified by flow cytometry.The 4th passage cells were used for experiment,and they were randomly divided into 5 groups:the osteogenic agents (10-8mol/L dexamethasone,50?g/ml ascorbic acid and 10mmol/L beta-sodium glycerophosphate) were used alone in the control group (group A),and the combination of osteogenic agents and different doses of strontium chloride (3.75?10-3,3.75?10-2,3.75?10-1 and 3.75mmol/L) were used in group B,C,D and E.The proliferation level,alkaline phosphatase (ALP) activity and osteocalcin (OCN) content of MSCs were determined by MTT colorimetric assay,enzyme-labeled method and radioimmunological method,respectively.The amount and area of calcium nodules in each group were observed by alizarin red staining.Results The proliferation and osteogenic differentiation rate of each group increased significantly with the lapse of culture time(P

Objective To provide research means for study of buccal cavity vitodynamics and design of optimized dental prosthetic restoration and prosthesis,give model for virtual surgery effectiveness analysis of the varied mandible surgery program.Methods A middle-aged man with normotrophic temporomandibular system was chosen and 123 widths of two-dimensional CT scan images were obtained through scanning his mandible by spiral CT scanner.The precise shaped mandible CAD mode was established through surface fitting by CATIA of three-dimensional spot-cloud transformed from two-dimensional CT images by image processing software,and the finite element model required for mandible surgery program was established by MSC.Patran.Results The full dentition mandible CAD models and three-dimensional finite element models were established.Conclusion The normal three-dimensional finite element mandible model can really reflect the geometrical feature of mandible and has good similarity to physical mandible and it can be used as a research means for biomechanical studies.The model can be also provided pre-operative designed quantitative method for the variety of mandible surgeries.

Objective To observe the effects of minimally traumatic puncture drainage of hematoma combined with Salviae Miltiorrhizae injection(丹参注射液) on the edematous volume around the lesion and neural functional defect in patients with hypertensive cerebral hemorrhage.Methods Eighty-nine patients with hypertensive cerebral hemorrhage were randomly divided into two groups: treatment group(n=45) and control group(n=44).All the patients had received minimally traumatic puncture drainage of hematoma,dehydration therapy,hemostatics,anti-inflammatory and anti-hypertensive agents, etc.In addition,Salviae Miltiorrhizae injection was continuously injected intravenously in the patients in the treatment group for three weeks.Cranial CT was performed to measure the volume of edema around the lesion at 7,14 and 21 days before and after operation,neurologic impairment degree scores(NDS) were assessed by National Institutes of Health Stroke Scale(NIHSS),and at the same time the fatality rate and re-hemorrhagic situation were observed at 14 and 30 days before and after initiating the operation.Results The areas of perilesional edema in both groups were conspicuously diminished at 7,14 and 21 days after initiating the operation,the area of perilesional edema diminished gradually,and significantly smaller in the therapeutic group than that in the control group at 14 and 21 days(P

ObjectiveTo evaluate the effects of expanded polytetrafluoroethylene (e-PTFE) and collagen tubes in the repair of facial nerve in rabbits.MethodsThe facial nerves of rabbits were transected and removed for 5 mm. The nerve ends were then repaired with an e-PTFE or collagen tube, and with an autologous nerve graft as control. After 7 days, 1 month and 3 months, the animals' neural conductive velocity were determined. And then, the nerve specimens were taken out, and the myelinated fibers across the specimen were counted with histological examination.ResultsOn the 7th day, no neural regeneration was observed. But new forming neural fibers across the biocompatible materials and autologous nerve grafts were seen in the following 3 months, while the number and conductive velocity of myelinated fibers varied significantly at the different time points.Conclusione-PTFE and collagen conduits are effective in the repair of peripheral nerves.

ObjectiveTo investigate the influence of phosphoinositide 3-Kinase-C2-gamma (PI3Kγ)on pancreas acinar cells autophagy in experimental acute pancreatitis in mice and explore its significance.MethodsEighteen C57BL/6 wild type (WT) and eighteen PI3Kγ knockout (KO) mice were randomly divided into control group (n =6) and acute panereatitis (AP) group (n =12),respectively.AP models were induced by intraperitoneal injection of 50 μg cerulein/kg body weight,once the other hour for seven times.The mice were sacrificed 7 hours after model induction.The pathological changes of the pancreas were observed through microscope,LC3 dots were determined by immunofluorescence,the trypsin activity was measured by fluorescence spectrophotometer,and the expression of autophagy related protein beclin1,p62 and LC3- Ⅱ were measured by Western blot.ResultsThe autophagy vacuoles counts in pancreatic tissue of WT mice and KO mice were (5.14 ±0.85),(2.25 ±0.54)/HPF,the LC3 immunofluorescence dots counts were (78.6 ±9.38),( 26.4 ± 4.21 )/HPF,the trypsin activities were ( 0.827 ± 0.126 ),( 0.358 ± 0.098 ) pmol/mg protein,the difference between the two groups was statistically significant ( P ＜ 0.05 ).The p62 protein expression was greatly decreased in WT mice compared with their KO counterpart (0.11 vs 0.92,P ＜ 0.05 ),while the expressions of LC3 Ⅱ,beclin1 were greatly increased in WT mice compared with their KO counterpart ( 1.82 vs 0.93,1.43 vs 1.05,P ＜ 0.05 ).Conclusions PI 3 Kγmay up- regulate autophagy of pancreatic acinar cells during acute pancreatitis in mice,then promote trypsinogen activation and necrosis of acinar cells.

Objective To Study the effect of long-term triptolide use on the content of the normal rat plasma ACTH.Methods 20 male SD rats were divided into 2 groups randomly,and gavaged for 7 weeks.The control group was 10 with 2%propylene glycol 2ml/kg,bid;the group of Triptolide was 10 with 2% the mixture of propylene glycol and Triptolide 20?g/kg,bid.We used radioimmunoassay to detecet the content of ACTH in rat's plasma and immunocytochemistry to detecet the expression of ACTH in pituitary. Results The content of ACTH in the group of the Triptolide had significant difference as compared with control group.The expression of ACTH in the group of the Triptolide was higher than that of control group. Conclusion These results suggested that one of the possible mechanism of the Triptolide in the HPAA might be exciting pituitary ACTH neurons,thus causing the content of ACTH increasing.

OBJECTIVE:To prepare adriamycin-loaded PLGA-PLL-PEG nanoparticles,and study its antitumor activity. METH-ODS:PLGA-PLL-PEG with the polymerization of PLGA-PLL and activated polyethylene glycol was used as carrier for adriamy-cin,and adriamycin-loaded PLGA-PLL-PEG nanoparticles were prepared. The shape size,particle size distribution,adriamycin con-tent of nanoparticles were detected,drug loading and encapsulation efficiency were calculated. Cumulative release rate (Q) of nanoparticles and adriamycin within 144 h and its proliferation inhibition rate on breast cancer HeLa cells were compared,and half inhibitory rate (IC50) was calculated. RESULTS:Prepared adriamycin-loaded PLGA-PLL-PEG nanoparticles were regular circular with good dispersion and no adhesion. The average particle size was (136.7 ± 9.3) nm (n=5),average encapsulation efficiency was(76.67±8.63)%,average drug loading was(3.86±0.55)%(n=3). Q12 h of adriamycin had reached 100%;Q12 h of adriamy-cin-loaded PLGA-PLL-PEG nanoparticles was 52.9%,Q144 h was 81.2%. The inhibitory rate of adriamycin-loaded PLGA-PLL-PEG nanoparticles on HeLa cells increased slowly than adriamycin;IC50 were 1.844,0.345 μg/mL,respectively. CONCLUSIONS:Adri-amycin-loaded PLGA-PLL-PEG nanoparticles are prepared successfully,showing good sustained-release effect and more significant inhibitory effect than adriamycin.

Objective: To prepare human cementum extract and to assess its protein content. Methods: Human permanent teeth were collected from the oral surgery clinic. Cementum was obtained from freshly extracted healthy teeth without inflammation.Connective tissue adhereing to the root surfaces was removed, and cementum was harvested with a curette. Then the cementum was treated by CH 3COOH and guanidine respectively to obtain two extracts. Protein content was assessed by sodium dodecyl sulphate ( SDS) polyacrylamide electrophoresis. Results: Extract obtained from CH 3COOH treatment consisted of two kind of proteins ( M r 55 000 and M r 68 000); that of guanidine consisted of four kind of proteins ( M r 62 000, M r 60 000 , M r 5 5000 and M r 41 000).Conclusion: The methods used is an applicable way to prepare cememtum extracts.

objective: To produce titanium dioxide hydrogel layer on the pure rough titanium(Ti) surface. Methods: Pure Ti discs( d =15mm) were polished to 600 grind, sandblasted and etched with acid, socked in 60 ℃ 5 mol/L NaOH solution for 24 h and then heated to 600℃ for an hour to get goughening, alkaline and heat treated Ti(RAH). The smooth, rough and RAH surfaces were analyzed with scanning electron microscope(SEM) and energy despersive X ray analysis(EDXA). Results: On smooth surfaces only regular polished grooves could be seen, while holes in different diameters formed on rough surfaces. A porous framework was found on the surfaces of the RAH observed by SEM. EDXA showed that the smooth and rough surfaces were consisted of 100% Ti, while there were a lot ofoxygen and sodium in RAH discs. Apatite formed on the RAH Ti surfaces when it is soaked in simulated body fluid for two weeks. Conclusion: A porous Ti dioxide hydrogel layer forms on the rough titanium substrate during alkaline and heat treatment.

Objective: To study the bioactivity of human cementum extract . Methods: Cementum was harvested from freshly extracted heatlhy teeth and cementum extract was prepared by guanidine. Human gingival fibroblast and MC3T3 E1 osteoblast were cultured. The cells were incubated in DMEM with cementum extract concentration 0, 2.5, 5, 10 or 20 ?g/ml for an hour respectively, the cell attachment rate was measured by cell counting. The attachment rate of the cells in different incubation time(30 min,60 min, 90 min, 120 min) in DMEM containing 10 ?g/ml cementum extract was also assayed.Results: The extract increased the cell attachment rate in a concentration and time dependent effect. The extract at the concentration of 10 ?g/ml and with exposuse time of 90 min gave the most effective increase of cell attachment. Conclusion: Human cementum extract prepared by guanidine contains some bioactive proteins that promote the attachment of gingival fibroblasts and osteoblasts.