Abstract: To investigate the status and influencing factors of tooth loss among the elderly population in China, so as to provide insights into early prevention of tooth loss. Methods: Based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS), data of the elderly people aged 65 years and older who participated in the survey in 2018 were collected, including demographic information, lifestyle, dietary habits, medical history, number of teeth remaining and self-assessment indicators. The status of tooth loss among the elderly were described based on the standard of 28 teeth, and factors affecting tooth loss were analyzed using a multivariable ordinal logistic regression model. Results: A total of 5 260 people was recruited, including 3 346 males (63.61%) and 1 914 females (36.39%). The median age was 78.00 (interquartile range, 18.00) years. The median number of teeth remaining was 12.00 (interquartile range, 23.00), and the median number of missing teeth was 16.00 (interquartile range, 23.00). Multivariable ordinal logistic regression analysis showed that the elderly who were female (OR=1.270, 95%CI: 1.098-1.470), had advanced age (OR=1.090, 95%CI: 1.083-1.098), lived in rural areas (OR=1.369, 95%CI: 1.165-1.610) and urban areas (OR=1.208, 95%CI: 1.027-1.422), smoked (past, OR=1.471, 95%CI: 1.240-1.746; always, OR=1.545, 95%CI: 1.300-1.838) and brushed teeth less than once a day (OR=1.791, 95%CI: 1.488-2.160) had more missing teeth; while the elderly who had high levels of education (junior high school, OR=0.819, 95%CI: 0.681-0.972; high school, OR=0.626, 95%CI: 0.507-0.771; college and above, OR=0.468, 95%CI: 0.334-0.657), kept physical exercise (OR=0.840, 95%CI: 0.736-0.958) and were overweight/obese (OR=0.868, 95%CI: 0.769-0.980) had less missing teeth. Conclusion Gender, age, residence, educational level, smoking, physical exercise, teeth brushing frequency and overweight/obese are the influencing factors for tooth loss among the elderly in China.

Objective: To study the effect of treatment of articulation disorder in patients with velopharygeal incompetence(VPI) after operation for cleft palate. Methods: Articulation disorder was treated by velophary-geal obturator in 135 patients with VPI, the rate of VPI(RVPI),improving rate of VPI(IRVPI),the value of third formant frequency(F3)of Chinese vowels and pronunciation were observed before and 180 days,1 and 2 years after treatment. Results: After treatment RVPI was decreased (P

Objective To discuss the foreground of application of reverse engineering reconstruction of dental models and to establish the foundation of developing a system for complete denture CAD/CAM. Methods The models of an edentulous jaw were measured with reverse engineering, and the 3D models were reconstructed with a computer. Results 3D models of the edentulous jaw were achieved. The characteristics of these 3D images were clear and accurate. Conclusion CAD models are reconstructed with reverse engineering accurately and technical problems in 3D model of complete denture CAD/CAM are resolved.

Objective To establish 3D data-base on artificial resin teeth with 3D layer scanning digitizer. Methods Artificial resin teeth were measured with a CMS-400 3D digitizer by cutting and scanning layer-by-layer, 3D data points of each tooth acquired and the 3D models of these teeth reconstructed with a computer. Results 3D models of 3D data-base on artificial resin teeth were obtained. The characteristics of these 3D images were clear and accurate. Conclusion The complicated teeth moulds can be measured accurately with the 3D digitizer since there are no measuring blind spots.

BACKGROUND:It can be theoretical y speculated that the combination of titanium, micro-arc oxidation coating and arginine-glycin-aspartic acid (RGD) polypeptide wil show better mechanical and biological properties. OBJECTIVE:To observe the microstructure and cellproliferation of the titanium and micro-arc oxidation coatings modified with RGD polypeptide by different modification methods. METHODS:Ninety specimens of pure titanium and micro-arc oxidation coatings were divided into three groups, with 30 specimens in each group. The first 30 specimens were pure titanium physical y decorated with RGD polypeptide only. The other two groups of specimens were physical and chemical coupling adsorption RGD polypeptide micro-arc oxidation samples, respectively. The fluorescence microscope was used to observe the effects and amounts of grafting RGD polypeptide on each sample. Content of the RGD polypeptide on the surface of the specimens were measured by X-ray photoelectron spectroscopy. The mouse bone marrow stromal cells were cultured on the surfaces of three groups samples, and the adhesion and proliferation of the cells cultured for 3 hours, 12 hours, 24 hours and 3 days were observed by optical microscope respectively. RESULTS AND CONCLUSION:There were green fluorescence spots, with varying size and amount, on the surface of specimens in three groups. In the unit field of view, the fluorescence was the strongest in chemical coupling adsorption RGD polypeptide micro-arc oxidation samples, indicating that these specimens were grafted with many polypeptides. In physical coupling adsorption RGD polypeptide micro-arc oxidation samples, smal amount of polypeptides were found on the surface, and the content of the RGD polypeptide was the highest in chemical coupling adsorption RGD polypeptide micro-arc oxidation samples. No apparent cytotoxicity was observed in three groups. The cellproliferation was the best in chemical coupling adsorption RGD polypeptide micro-arc oxidation samples. Experimental findings suggest that, chemical coupling method can wel fix the RGD polypeptides on the surface of pure titanium samples containing micro-arc oxidation, without any cytotoxicity, which contribute to promote the cellgrowth and proliferation.

BACKGROUND: One of the key neuropathological changes in Alzheimer disease is that neurofibrils over phosphorylated cytoskeletal protein (such as r and neurofilaments) composed of entwist together, and the phosphorylation of τ protein can be catalyzed by cyclin dependent kinase 5 (CDK5),however whether the phosphorylation of neurofilaments can be catalyzed by CDK5, as well as its role in the pathogenesis of Alzheimer diseases is less acknowledged.OBJECTIVE: To explore the role of over-expression of intracellular CDK5 in the phosphorylation of neurofilamentsDESIGN: Randomized controlled study.SETTING: Biochemical and Molecular Biological Department of Tongji Medical College, Huazhong University of Science and Technology.MATERIALS: This study was conduced at Biochemical and Molecular Biological Department of Tongji Medical College, Huazhong University of Science and Technology between February and May 2001. In vitro cultured rat neuroblastoma cell strain (N2a) was adopted as subjects.METHODS: In vitro cultured N2a cells were divided into 2 groups, namely transfection group and non-transfection group. In transfection group,CDK5 gene was transfected into N2a cell line by using liposome transfection technique so as to obtain N2a/CDK5 cell line stably expressing CDK5, immune-precipitation and enzyme activity assay was used to detect the CDK5 activity, meanwhile immunofluorescence technique and immuneblot assay was used to detect CDK5 expression and phosphorylation of neurofilaments.MAIN OUTCOME MEASURES: Phosphorylation of neurofilaments in both groups.RESULTS: In transfection group of N2a cell line, CDK5 expression increased presented by deep coloration of SMI31 antibody and weak coloration of SMI32 antibody, implying hyper-phosphorylation of neurofilaments. Meanwhile, the activity of CDK5 was 3.5 times higher than that in non-transfection group.CONCLUSION: Intracellular over-expressison of CDK5 would lead to hyperactivity of CDK5 and hyper-phosphorylation of neurofilaments, however the hyper-phosphorylation of neurofilamentsmight invlove in the pathological development of AD.

ObjectiveTo investigate the expression of E-cadherin and β-catenin in the primary colorectal carcinoma and metastatic lymph nodes and it's clinical significance. MethodsImmunohistochemical analysis of Ecadherin and β-catenin was performed in colorectal mucosa( n =20 ,group A) ,colorectal carcinoma without metastasis ( n = 25, group B) and colorectal carcinoma with metastatic lymph nodes ( n = 39, group C) The expression of E-cadherin and β-catenin and the metastasis and prognosis of colorectal carcinoma were observed. ResultsThe strongly positive expression of E-cadherin in primaries of group C (5.1％ ) was obviously lower than in group B ( U = 2. 149,P =0. 032) ,whereas no statistic differences of the expression of E-cadherin between primaries and metastases of group C were observed(P =0.186). There was no difference of the expression of β-catenin between group B and group C,the same of primary colorectal carcinoma and self control lymph nodes of group C(P =0.235 and P =0. 715). There was positive correlation between membranous down regulation of E-cadherin and β-catenin in group C( r = 0.387 ,P =0.024) ,but no relationship was found in group B( r = 0.080 ,P = 0.723 ). ConclusionThe decreased membranous expression of E-cadherin in the colorectal carcinoma was correlated with lymph nodes metastasis, and was obviously related to membranous down regulation of β-catenin. There was no relevance between the expression of β-catenin and the lymph nodes metastasis of colorectal carcinoma.

Objective To provide the data of mandible and zygomatic arch, including the space distance of mandible angles, depth and length of zygomatic arch, by direct measurement and related analysis at home position of corpse in Chinese Han for medical aesthetics. Methods The vernier callipers were used to directly measure the every indexes of mandible and zygomatic arch in the formalin-fixed male and female adult corpses (50 each) and to proceed the related analysis. Results The results showed that male mandible thickness was (12.60?1.26) mm, mandible height (33.60?3.35) mm, mandible length (77.60?7.80) mm , width of mandible ramus (34.80?3.50) mm, height of mandible ramus (67.20?6.70) mm, depth of zygomatic arch (9.54?1.19) mm, length of zygomatic arch (40.60?4.97)mm, and thickness of mandible angle (12.20?0.67) mm in male; Mandible thickness was (10.70?0.98) mm, mandible height (29.40?2.64) mm, ramus of mandible height (74.00?7.07) mm, width of mandible (31.10?3.04) mm, height of mandible ramus (64.00?5.53) mm, depth of zygomatic arch (8.67?1.09) mm, l ength of zygomatic arch (36.50?4.59) mm, and thickness of mandible angle (13.80?1.28) mm in female. Conclusions The breadth between bilateral angle of mandible could come to reckoning the depth of zygomatic arch, the length of zygomatic arch and other indexes of mandibles. Those data are useful in aesthetics and preparation of the compound.

Objective To detect the expression levels of renal tissue M-type phospholipase A2 receptor 1(PLA2R1) antigen and its antibody in the patients with membranous nephropathy(MN).Methods Fifty-eight cases of biopsy-proved idiopathic membranous nephropathy(IMN),fifteen cases of hepatitis B-associated membranous nephropathy(HBV-MN) and seventeen cases of V type lupus nephritis(V-LN) were selected.Renal tissue PLA2R1 antigen was detected by indirect immunofluorescence and colocaliazed with IgG4.Serum anti-PLA2R1 antibody was simultaneously examined.The expression difference of PLA2R1 antigen and antiPLA2R1 antibody in MN was analyzed.And the differences of clinical data were analyzed between PLA2R1 positive and negative patients.Results The PLA2R1 antibody was not found in the renal tissue and serum of the patients with LN and HBV-MN;PLA2R1 antigen was found in 81.03％ of IMN patients,and its antibody was found in serum of 70.69％ of IMN patients.PLA2R1 antigen and IgG4 co-localization all deposited along glomerular capillary loop presenting as fine granules.The 24 h urine protein level in the patients with PLA2R1 antigen deposition in renal tissues was higher than that in the patients without PLA2R1 deposition (P＜0.05),moreover serum albumin level was lower than that in the patients without PLA2R1 deposition(P＜0.05).Conclusion The sensitivity and specificity of renal tissue PLA2R1 antigen in the diagnosis of IMN are higher.The expression of PLA2R1 antigen in renal tissue by biopsy is significantly correlated with the clinical severity.

The abdominoperineal excision (APE) is still one of the standard operations for low rectal cancer. The exralevator APE can reduce the positive rate of circumferential margin and perforation rate of rectal cancer, but the incidence of postoperative complications is relatively high. With the continuous development of minimally invasive surgery, the transperineal minimally invasive Abdominoperineal excision (Tpm-APE) is proposed. Compared with traditional APE, the Tpm-APE has potential technical advantages, but there is a lack of large sample and multicenter clinical research evidence. The authors share the design and results of an international multicenter clinical study to investigate the clinical practice of Tpm-APE in the treatment of low rectal cancer.