Objective: To study the corrosion resistance of the ortho do ntic magnets with titanium nitride (TiN) coating. Methods: The m agnets coated TiN film were immersed into artificial saliva at 37 ℃ for two mon ths. During the immersion, the concentration of iron ion in the artificial saliv a was analyzed with atomic absorption spectrophotometry(AAS). After immersion, t he weight change of the magnets was measured.The magnets coated with nickel film and without coating were used as the controls.Results: In all t he groups, iron ion concentration in the artificial saliva increased with the in crease of immersion time(P

Objective: To study the corrosion resistance of orthodontic magnet with titanium nitride coating in artificial saliva. Methods: 6 samples of magnet in the size 3 mm?5 mm?7 mm were prepared.3 of them were coated with titanium nitride by plasma enhanced chemical vapor deposition,another 3 without coating were used as controls.The samples were immersed into artificial saliva at 37 ℃ for one month. Then the surface characters of two kinds of magnets were observed with the naked eye and by electron-probe microanalysis (EPMA). Results: The surface of the magnets with titanium nitride coating was fine and close in texture and there were no cleft and disintegrated area. However, that of the magnets without titanium nitride coating was uneven and coarse in texture,and there were evident clefts and disintegrated areas. Conclusion: The corrosion resistance of orthodontic magnets with titanium nitride coating is stronger than that without coating.

BACKGROUND: The osteoblastogenetic function of stem cell and local vasoformation is an important influencing factor in bone tissue engineering restoration.OBJECTIVE: To investigate the function of osteoblast induced, cultured and differentiated from mesenchymal stem cells(MSCs) and the expression of vascular endothelial growth factors(VEGF) in rabbits in itro.DESIGN: A single sample study and repetitive observational measurement by using cells as subjects SETTING: Department of histology and embryology in a university MATERIALS: The study was conducted in the Department of Histology and Embryology of Guangdong Medical College between March and December of 2002. The subjects were rabbits' MSCs.METHODS: The MSCs of newborn rabbits ere isolated and cultured. The cultured cells were induced to osteoblastogenesis with an osteo-inductive medium containing dexamethasone, ascorbic acid and β-glycerophosphate to observe the coloration of alkaline phosphates(ALP) and the formation of mineralized nodule in the cultured cells.MAIN OUTCOME MEASURES: ① observation of cell morphology, ②identification of steoblastogenesis from the cultured cells ③ expression of VEGF in osteoblasts derived from the cultured cells RESULTS: fter MSCs osteo-inductive culture, cells had strong ALP staining with the formation of mineralized node, and the VEGF expression enhanced with the grey scale of 132.3 ± 4.6, which was significantly different from that of the VEGF expression in MSCs( 148.5 ± 5.3) ( P ＜ 0.05).CONCLUSION: MSCs can be induced into osteoblasts with enhanced expression of VEGF, which might participate in the formation of endothelial cells.

Objective:To assess the periodontal diseases as a possible risk factor for preterm and low birth weight. Methods: A population-based, cross-sectional study was carried out in Hubei. The samples were chosen randomly by the rule of admittance. Socio-demographic information relating to health and maternal habits was collected through a questionnaire. The clinical parameters were debris index-simplified (DI-S), sulcus bleeding index (SBI), probing pocket depth (PD) and clinical attachment loss (CAJ). The birth time and weight were recorded. The result was analyzed with chi-square test and logistic regression analysis.Results: The incidence of preterm low birth weight was 12.3%. The gingivitis and periodontitis were diagnosed in 86.6% and 64.2% of preterm low birth weight cases. The odds ratio of having gingivitis and preterm low birth weight was 1.30(95%confidence interval: 0.53-3.22). The odds ratio of having periodontitis and preterm low birth weight was 2.69(95%confidence interval: 1.37-5.27). Conclusion: The periodontal diseases of pregnancy can be regarded as an important risk factor for preterm low birth weight.

Myeloid-derived suppressor cells (MDSCs),a heterogeneous population of immature myeloid cells,play an important role in immune tolerance and immune suppression.In recent years,more and more research results show that the prostaglandin E2 (PGE2) has an inseparable relationship with MDSCs,and PGE2 through its relevant receptors,regulating signal transducer and activator of transcription 3 (STAT3) and protein kinase A cell signaling pathways and secretion cytokines in tumor microenvironment,affects the development,differentiation and function of MDSCs.

OBJECTIVEThis study was conducted to observe dynamically the serum and stool level of IL-2, IL-6 and IFN-alpha with RV enteritis, and to analyse the relation of them and their relation to clinical manifestations.

METHODSThe double-antibody sandwich ELISA technique was applied.

RESULTSThe positive rate of RV in 119 enteritis cases was 63.0% and the peak month was November. These cytokines had different peak phases in the course of disease. The earliest cytokine which had peak phase was IFN-alpha, the last ones were serum and stool IL-2. There was a negative relation between stool IL-2 and IL-6 (P<0.01). There were positive relation between IL-2 and IFN-alpha, stool IL-6 and IFN-alpha, serum IL-2 and IL-6, stool IL-2 and the recovery time of the enteritis (P<0.01 or P<0.05). Serum and stool level of IL-2 and IFN-alpha had positive relation to the number of lymphocyte plus mononuclear cells (P<0.01 or P<0.05).

CONCLUSIONSIL-2, IL-6 and IFN-alpha play important roles of immunoregulation in RV enteritis, and have close relation to clinical manifestations.

Enteritis ; blood ; virology ; Feces ; chemistry ; Female ; Humans ; Infant ; Interferon-gamma ; metabolism ; Interleukin-2 ; metabolism ; Interleukin-6 ; metabolism ; Male ; Rotavirus Infections ; blood

Objective To develop Chinese version of the Manchester patient safety framework, and evaluate the feasibility of its clinical application. Methods The Manchester patient safety framework (MaPSaF) was transformed into Chinese version by translation and back-translation together with inquiries from experts. The trial study was done firstly among 136 nurses in five pilot wards and followed by five times of focus-oriented group interviews. A semi-structured, in-depth interview was then performed in 12 randomly selected participants and acquired data were analyzed by category analysis. Result Two themes were abstracted: Chinese version of MaPSaF showed a good practicability, effectiveness and operability and it was effective for deepened understanding of patient′s safety culture. Conclusion The Chinese version of MaPSaF can be used for safety culture evaluation during nursing process in China.

Objective To investigate the role of triggering receptor expressed on myeloid cells 1 (TREM1)in rats with neuropathic pain and its possible mechanism.Methods Forty-eight male a-dult Sprague-Dawley rats,weighing 220-300 g,were successfully placed intrathecal catheters,and then randomly divided into 4 groups (n=1 2 ):sham operation group (group S),neuropathic pain group (group CCI),TREM1 shRNA group (group RNAi)and negative lentivirus group (group Vi-rus).The neuropathic pain was induced by chronic sciatic nerve compression injury (CCI).In group RNAi,30 μl pGLVU6/RFP/Puro-shRNA (1×109IU/ml)was injected intrathecally 1 week before modeling.Group Virus was injected with 30 μl negative lentivirus,whereas group CCI and group S with equal amount of normal saline.MWT and TWL were measured 1 day before (baseline)and 1,3, 7,14 day after modeling.When behavioral test finished,the expression levels of TREM1,TLR4, MyD88,IκBαand p-NF-κB p65 in spinal cord were determined by Western blot.Whereas the mRNA expression levels of IL-1β,TNF-αand IL-6 in spinal cord were measured by RT-PCR.Results Com-pared with group S,the expression levels of TREM1 in groups CCI and Virus significantly increased (P<0.05).While compared with group CCI,the TREM1 expression of group RNAi in spinal cord significantly decreased (P<0.05).Compared with group S,MWT and TWL of groups CCI,Virus and RNAi after modeling and the expression of IκBαsignificantly decreased (P<0.05),whereas the expression of TLR4,MyD88,p-NF-κB p65 increased significantly (P<0.05),as well as the expres-sion of IL-1β,TNFαand IL-6 mRNA (P<0.05).Compared with group CCI,the MWT and TWL of group RNAi after modeling and the expression of IκBαremarkably increased (P<0.05),whereas the expression of TLR4,MyD88 and p-NF-κB p65 in the spinal cord remarkably decreased (P<0.05), as well as the expression of IL-1β,TNF-αand IL-6 mRNA (P<0.05).Conclusion TREM1 knock-down can alleviate neuropathic pain,the underlying mechanism might be the inhibition of TLR4/MyD88/NF-κB signaling pathway.

Microperimetry is a procedure to assess retinal sensitivity while fundus is examined directly.It is a psychophysical method which is rapid,safe and non-invasive.It combines analysis of function and morphology and has an eye tracking system that can improve the fixation stability of patient with eccentric fixation and fixation instable.Microperimetry is supplement to visual function,perimetry,and other visual function parameters.As deepening of research,its clinical application value in ocular fundus diseases including age-related macular degeneration,diabetic retinopathy,retinitis pigmentosa,Stargardt's disease,macular hole,rhegmatogenous retinal detachment and central serous chorioretinopathy needs to be further explored.