Objective:To analyze the stress magnitude and distribution of remaining dentin in posterior tooth residual root restored with post-core crown using three-dimension finite element method. And then to discuss the rational core design when repairing posterior tooth root post-core crown. Methods:The models of residual root of maxillary first molar restored with post-core crown were created by CT scanning,Mimics software and Abaqus software. Different number,length and material of post were used in the modeling. The post was cemented with zinc-phosphate cement. A load of 240 N was applied to the occlusal surface in four directions and tensile,shear,and von Mises stresses were calculated. Results:The maximum stress on remaining dentin increased markedly with increasing of loading angle. Conclusion:The loading angle have influence on magnitude and distribution of stress. The influence from loading angle is most apparent.

ObjectiveTo investigate the effectiveness of introducing CAD/CAM system into Prosthodontics experimental teachin.MethodsStudents from Chongqing Medical University with major of Dental Department in Grade 2007 was selected.To make all students master the basic knowledge of CAD/CAM system,problem-based learning was used to teach the undergraduate grasping the CAD/CAM system of the affiliated hospital.Results 90 ％ of the students showed strong interest in learning knowledge of the CAD/CAM system.98 ％ of the students could master CAD/CAM system knowledge.ConclusionCAD/CAM system knowledge is suitable for development of prosthodontics.It is necessary that the basic knowledge of CAD/CAM was introduced into prosthodontics experimental courses.

Chitin/Chitosan oligomers were prepared by the concentrated hydrochloric acid or enzymatic hydrolysis with chitinase and chitosanase and its transglycosylation reaction. Their preparation,isolation and analytical methods are reviewed.

Objective To analyze the clinical features of tsutsugamushi disease.Methods 113 cases of tsutsugamushi disease from 1991-2005 were reviewed.Results The symptoms of fever,eschar or ulcer,tetter and lymph node tu- mescence accounted for 100%,80.5% (91/113),6.2% (7/113) and 75.2% (85/113) respectively.Liver damage and pulmonary damage were observed in 75.2% (85/113) and 47.8% (54/113) cases.78.8% (89/113) cases were masculine in OX_K check.Conclusion Tsutsugamushi diseases showed complicated and multiple clinical manifestations and more attention should be paid to for avoiding misdiagnosis.

BACKGROUND:Animal studies showed that functional early load or immediate load on immediate implant did not affect the prognosis of implant.
OBJECTIVE:To analyze the effect of immediate loading with different forces on the binding surface of immediate implant bone ossification.
METHODS:Six adult healthy male dogs were selected. Al teeth (three premolars) between cuspid teeth of lower mandible and the first molar were pul ed out. One implant (OSSTEM GSII) was immediately implanted, total y 36 implants. The vertical immediate loading by device was used on the implants at 24 hours after implantation. Grouped by the loading force values:0, 10, 20 N on the left three implants of each dog from front to back, 30, 40, 50 N on the contralateral three implants of each dog, at a frequency of 1 Hz for 10 minutes every day. The implant stability quotient (ISQ) was tested using resonance frequency measurement instrument (OSSTELL) at 0 day, 4, 8, and 12 weeks.
RESULTS AND CONCLUSION: With increased load forces, serum osteocalcin expression increased, and peaked on 20 N, but decreased in 30 N group, and lowest in 50 N group. At 4 weeks after immediate implantation, the ISQ values were slightly less than pre-implantation in each group, especial y the 50 N group. At 8 weeks after immediate implantation, ISQ values were increased in each group to different degrees. The increased degree of the 20 N group was maximal. At 12 weeks, a peak value was detected in each experimental group. The implants could bind to bone tissues to different degrees. The range of implant-bone interface formation was positively associated with time. Results indicated that the smal force cannot impact implant-bone ossification, but promotes it in a manner, but large force value (≥ 20 N) wil affect the stability of the implant-bone ossification.

Objective To develop a feasible method for evaluating uncertainty in colony forming units(CFU)on the disinfected skin of nurses of operation room.Methods A nurse of operation room in a hospital involved the study.Ten spots on her disinfected hand skin were selected for evaluation of uncertainty in the acquired data and analysis of reliability of the evaluation methods,according to Technical Norms for Monitoring the Disinfection and Sterilization Quality in Hospitals in Jiangsu Province and JJF1059-1999 Evaluation and Expression of Uncertainty in Measurement.Results The CFU on the disinfected skin of nurse was(4±2)cfu/cm2, which indicated that the disinfection of the nurse's hands was not qualified.Conclusion The evaluation method by our study is reliable for evaluating the uncertainty in CFU on nurse’s disinfected hand skin.It is simple and fitful for the uncertainty evaluation of hospital disinfection effect.

Background and purpose: MORC2 (microrchidia family CW-type zinc finger 2, MORC2) is a newly identified chromatin remodeling protein that plays key roles in DNA-based biological processes including gene transcription and DNA damage repair. However, its functional role in breast cancer development and progression re-mains unknown. ALDH1A3 (aldehyde dehydrogenase 1 family member A3), a member of the aldehyde dehydrogenases (ALDH) superfamily, is a putative breast cancer stem cell marker, but its regulatory mechanism in breast cancer is poor-ly characterized. This study aimed to investigate the effects of knockdown of endogenous MORC2 on the expression levels of ALDH1A3 and the breast cancer stem-like phenotype in MCF-7 cells. Methods: Human breast cancer MCF-7 cells were infected with negative control short hairpin RNAs (shNC) and specific shRNAs targeting human MORC2 (shMORC2), followed by selection with puromycin to generate stable MORC2 gene knockdown cell lines. Western blot and real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR) were used to examine the protein and mRNA levels of ALDH1A3 in MCF-7 cells stably expressing shNC and shMORC2. Microsphere formation and fluo-rescence-activated cell sorting (FACS) assays were used to analyze the effects of knockdown of MORC2 on the breast cancer stem-like phenotype. Results: Western blot and RTFQ-PCR analyses revealed that the protein and mRNA levels of ALDH1A3 were significantly down-regulated in shMORC2 expressing cells as compared with shNC -transfected control cells. Moreover, mammosphere formation assay showed that knockdown of endogenous MORC2 in MCF-7 cells significantly reduced the ability of cells to form microspheres. Consistently, FACS assays demonstrated that shMORC2-transfected cells had a lower proportion of ALDH-positive stem cells as compared with shNC expressing cells. In contrast, knockdown of MORC2 did not significantly affect the CD44+CD24- stem cell population. Conclusion:MORC2 promotes a breast cancer stem-like phenotype through, at least in part, regulating ALDH1A3 expression.

BACKGROUND:Activating transcription factor 4 is found as an activating factor that can regulate osteogenic differentiation and function, and plays a critical role in the osteogenic differentiation.
OBJECTIVE:To investigate the expression and significance of activating transcription factor 4 in the osteogenic differentiation of bone marrow mesenchymal stem cells from Sprague-Dawley rats.
METHODS:Bone marrow mesenchymal stem cells from Sprague-Dawley rats were cultured using the whole bone marrow adherence method, and ossification revulsant was added to induce passage 3 cells. cells with no osteogenic induction served as controls. RT-PCR and western blot assay were employed to dynamical y monitor expression of activating transcription factor 4.
RESULTS AND CONCLUSION:RT-PCR results showed that activating transcription factor 4 mRNA expression increased with the increasing osteogenic differentiation, and peaked at day 16. Western blot analysis showed that the protein expression of activating transcription factor 4 tended to increase with the increasing osteogenic differentiation, peaked at day 16 and stil maintained at a higher level at day 19. Compared with the uninduced cells, activating transcription factor 4 in the induced cells exhibited a higher expression at mRNA and protein levels (P<0.05). These findings indicate that activating transcription factor 4 expression is elevated during osteogenic differentiation, showing a positive correlation with osteogenic ability of bone marrow mesenchymal stem cells.

Objective To examine the effects of glucose on the expression of P38 MAPK and TGF?2 in cultured human umbilical vein endothelial cells.Methods Human umbilical vein endothelial cells(HUVECs)were incubated in a culture medium with 11.2 mmol/L,16.8 mmol/L and 33.6 mmol/L glucose concentrations for 24 h,48 h and 72 h respectively.The expression P38 MAPK and TGF?2 was measured by RT-PCR and Western-blot.Results When D-glucose concentrations rose,HUVECs exposed to high glucose concentration(11.2 mmol/L,16.8 mmol/L and 33.6 mmol/L)showd increase in cell expression of P38 MAPK and TGF?2 after 48 h and 72 h exposure as compared with those cultured in medium of low glucose concentration(5.6 mmol/L).ConclusionHigh concentration of glucose can arrest the proliferative response.Even a short-term exposure of endothelial cells(ECs)to high glucose concentration may lead to their activation associated with increased expression of P38 MAPK and TGF?2.High Glucose Concentration on P38 MAPK and TGF?2 expression may participate the pathogenesy of diabetic retinopathy.

Objective To investigate the changes and clinical significance ot the expression ot microRNA in plasma and peripheral blood mononuclear cells in patients with schizophrenia.Methods 174 patients with schizophrenia in Danzhou People 's Hospital were selected as the case group and the other 80 healthy persons as control group The relative expression levels of 8 microRNA in two groups of plasma and pcripheral blood mononuclear cells were detected by real-time quantitative fluorescent PCR(MiR-195,MiR-346,MiR-181b,MiR-212,MiR-30e,MiR-432,MiR 7,MiR-34a),and the differences of microRNA in the plasma and peripheral blood mononuclear cells were compared between the two groups.ROC curve was used to analyze the sensitivity and specificity of microRNA as diagnostic criteria for schizophrenia and Logistic regression analysis of the relative risk of microRNA in schizophrenia.Results The expression levels of MiR-195,MiR-181b,MiR-132,MiR-30e,MiR-7 and in the patients of the case group(3.11±1.05,2.18±0.72,1.85±0.74 and 9.61±1.87) were significantly higher than those in the control group(4.48±1.07,2.92±0.86,3.53±1.07 and 11.96±2.73,P＜0.05 or P＜0.01).The expression levels of MiR-181b,MiR-212,MiR-30e and MiR-34a in peripheral blood mononuclear cells of patients in the case group (-4.20±1.16,0.27 ±0.55,-4.83± 1.05 and 2.64± 1.08) were significantly higher than those in control group (-3.56±0.81,0.91±0.68,-3.49±1.22 and 3.95±1.03,P＜0.05 or P＜0.01).Logistic regression analysis showed that plasma MiR-181b and MiR-30e were significantly relative risk (OR=2.357,95 ％ CI:1.361 ～ 4.093;OR=2.064,95 ％ CI:1.147～3.815),and peripheral blood mononuclear cells MiR-30e also had significant relative risk (OR=1.628,95 ％CI:0.914～2.926).ROC curve analysis showed that 95％CI and AUC in plasma and peripheral blood mononuclear cells of MiR-181b were 0.702 (0.784～0.632),0.658 (0.593 to 0.736),and plasma and peripheral blood mononuclear cell of MiR-30e were 0.775 (0.706～0.857),0.758 (0.686～0.839),respectively.Spearman correlation analysis showed that plasma MiR 181b and plasma MiR-30e were significantly correlated (r=0.547,P =0.043).Conclusion Abnormal expression of microRNA in patients with schizophrenia,and plasma and peripheral blood mononuclear cells MiR-181b and MiR-30e had good diagnostic value for schizophrenia patients.