Dental Porcelain ; Zirconium

BACKGROUND: The wear resistance and hardness of artificial tooth would affect repairing effects in clinic. However, there is lack of professional standard for resin teeth in China.OBJECTIVE: To provide a theoretic foundation for the choosing of the resin teeth in clinic via comparing the wear resistance and hardness among 7 different resin teeth.DESIGN, TIME AND SETTING: A contrast observation. The experiment was performed at the laboratory of Mechanical Engineering College, Shanghai Jiao Tong University from November 2003 to May 2004.MATERIALS: A total of 7 kinds of different resin teeth were selected, namely, hard multi-layer synthetic resin teeth (A); multi-layer synthetic resin teeth (B); synthetic resin teeth (C); EMDURA resin teeth (D); three-layer synthetic resin teeth (E); optostar four-layer synthetic resin teeth (F); and Cosmo HXL (G).METHODS: The wear test was processed by a pin-plate wear machine. The result was measured by the weight loss through wearing and the surfaces of the wear scar were observed by a scanning electronic microscope (SEM); hardness was measured by Knoop hardness. Meanwhile, the relativity between the hardness and wear resistance of resin teeth was analyzed.MAIN OUTCOME MEASURES: The wear resistance and hardness of resin teeth.RESULTS: According to the weight loss and SEM examination, the wear resistance of the different resin teeth was D>A>G>E>B>F>C; and the hardness of different resin teeth was D>A>G>E>F>B>C. The correlation coefficient between the weight loss and hardness was -0.888 (P < 0.01).CONCLUSION: The variation of the wear resistance of the resin teeth may influenced by their different components, molecular weight and manufacturel methods. There are positive correlation between the hardness and wear resistance of resin teeth.

BACKGROUND: Because of their size effect, nanometer particles (NPs) can combine molecular within cells, which can result in cell necrosis or apoptosis. But there are no systematic mechanisms of apoptosis induced by NPs about biological safety of NPs.OBJECTIVE: To investigate the effect of nano-hydroxyapatite particles on mononuclear macrophage in rat abdominal cavity at celluar and molecular level.DESIGN, TIME AND SETTING: A materials-cytology observation was performed at Shanghai Biomaterials Research & Testing Center from January 2001 to December 2008.MATERIALS: SD rats of clean grade were provided by SINO-BRITISH SIPPR/BK LAB. ANIMAL Co., Ltd.; NPs were provided by Shanghai Institute of Ceramics.METHODS: Peritoneal fluid was extracted under a sterility environment to in vitro separate and culture mononuclear macrophage using adherence method. The concentration of cell was adjusted at 2×10~9/L. At 300 W/40 kHz ultrasound, cell suspension containing 20,100 and 200 mg/L nano-hydroxyapatite particles was prepared to induce mononuclear macrophage for 24 hours, respectively. A normal control group was established.MAIN OUTCOME MEASURES: Ultrastructural phenotype was detected using transmission electron microscope; apoptotic rate was measured using AnnexinV-EGFP/PI staining; variation of apoptosis-related P53 gene expression was detected using Western Blot.RESULTS: Pseudopodia of mononuclear macrophage in the normal control group were intact, nuclear membrane was normal, and nucleoplasm was uniformed. After inducing by 20,100, 200 mg/L nano-hydroxyapatite particles for 24 hours, apoptotic morphological characteristics were typical in mononuclear macrophage. Compared with normal control group, apoptotic rate was significantly increased following the induction of 20 and 100 mg/L nano-hydroxyapatite (P< 0.01), and the increasing in the 100 mg/L nano-hydroxyapatite particle group was greater than 20 mg/L nano-hydroxyapatite particle group (P < 0.05). P53 protein was not observed in mononuclear macrophage in the normal control group. Following induction of varying concentrations of nano-hydroxyapatite particles, P53 protein expression was increased in the mononuclear macrophage, and the expression was positively related to concentration of nano-hydroxyapatite particles.CONCLUSION: Nano-hydroxyapatite particles can induce p53 expression through phosphorylation, which promotes downstream genes and finally results in cell apoptosis.

Objective To explore the correlation between adenoid hypertrophy and secretory otitis media.Methods The cases of adenoid hypertrophy were screened and selected by nasopharyngeal lateral X ray.We chose 58 normal children after the clinical examination as control group.In accordance with the degree of adenoid hypertrophy,they were divided into three groups:the normal group,middle-grade and high-grade groups of adenoid hypertrophy with the association between the degree of adenoidal hypertrophy and the incidence rate of secretory otitis media analyzed.Results There was no difference in the incidence rate of secretory otitis media between the normal and middle-grade groups.The incidence rates of secretory otitis media were significantly different between the normal and high-grade groups(P＜0.01).Conclusion The incidence of secvetory otitis media and the degree of adenoid hypertrophy showed positive correlation.The greater is the size of adenoids, the severer is the degree of obstruction of the nasopharyngeal cavity and the higher is the incidence of secretory otitis media.

B-cell translocation gene/transducer of erbB2 (BTG/TOB) protein family is a new antiproliferative protein family.Recent studies have found that BTG/TOB family is absent obviously in many tumor tissue specimens,such as lung cancer,breast cancer and thyroid cancer,and contributes to the genesis and progression of various malignancies.

Objective: To explore the active components with toxic effects in five Aconitum L. herbal medicines on Tetrahymena thermophila. Methods: The fingerprints of five Aconitum L. herbal medicines were established by ultra-high performance liquid chromatography (UPLC) and the toxicity was evaluated by using a TAM Air Isothermal Calorimeter on Tetrahymena thermophila SB110. Results: By analyzing the spectrum-effect relationships between UPLC fingerprints and toxic effects, the active components which had the toxic effects were obtained. Conclusion: This work provides a general model of the combination of UPLC and microcalorimetry to study the spectrum-effect relationships of the five Aconitum L. herbal medicines, which could be used to evaluate the toxic effects and analyze the principal toxic components of the five Aconitum L. herbal medicines. On the whole, this result provides the experimental basis for the safe use of the five Aconitum L. herbal medicines in clinic. © 2014 Tianjin Press of Chinese Herbal Medicines.

Objective To evaluate the effect of probe melting curve analysis and gene chips on detecting drug resistance of Mycobacterium tuberculosis against isoniazid and rifampicin. Methods Drug resistance was detected by gene chip and probe melting curve analysis in 46 cases of patients with sputum smear positive specimens, with L-J culture as the gold standard. Results In all the 46 cases, the detection of drug resistance genes against isoniazid was performed by probe melting curve analysis and gene chips, achieving the coincidences of 91.3% and 80.43% with those by L-J culture, respectively. The detection of drug resistance genes in 38 cases administered with rifampicin was conducted as well by the two techniques, achieving the coincidences of 84%and 89.4% with those by L-J culture. There were no significant differences between the two methods (P > 0.05). Conclusion The gene chip direct detection and probe melting curve analysis are of high value in diagnosis of tuberculosis, and they can be regarded as a diagnosis method of choice for tuberculosis. Both have the priorities of timesaving, high sensitivity and specificity.

group was also higher than that in the control group, Z=2.39, P<0.05,all which had significant difference, P<0.05.While no significant difference was found in the scores of the Geriatric Depression Scale or the Cornell Scale of Depression Disease between two groups, Z=1.21, P>0.05. Conclusions Reminiscence therapy improves cognitive function, the ability of self-care and social communicate of patients with mild to moderate dementia patients,so that it can improve further patients′quality of life.

Objective To detect the change of precursor protein of sol in breast cancer before and after the neoadjuvant chemotherapy,so as to find the serum protein marker of chemotherapy drug resistance in breast cancer.Methods Breast cancer patients with Ⅲ period neoadjuvant chemotherapy were enrolled in the study.The serum specimens of the patients were obtained.Two-way gel electrophoresis was used to get the gel map before and after chemotherapy,then the image map was analyzed by gel analysis software.The differentially expressed proteins point was screened before and after chemotherapy.Serum protein differences were identified with matrix auxiliary laser disi ntegrate series time of flight mass spectrometer (MALDI-TOF-MS),including coagulation sol precursor protein.Western blot was used to test the variation trend of them before and after chemotherapy.Results Coagulation sol precursor protein levels fell after neoadjuvant chemotherapy in resistance group.The variation trend of the results of western blot and that of the proteomics were consistent.Conclusion Coagulation sol precursor protein can be as the candidate serum marker of chemotherapy drug resistance in breast cancer.

The occurrence rate of long QT syndrome is 1/2 000,which accounts for approximately 10％ of cases of the sudden infant death syndrome.The morbidity is decreased after receiving appropriate therapy in early stage.Electrocardiogram (ECG) screening,with reliable results,is simple and feasible in infancy and can be used to conduct appropriate genetic testing.Neonatal screening is controversial because of individual differences in ECG results.Even there are some defects,it is still necessary to perform neonatal ECG screening which can improve prognosis in children with long QT syndrome.