BACKGROUND: There are many species of ceramic bonding systems supplied in market, the mechanical strength is aprerequisite condition for resin cement in clinical use.OBJECTIVE: To study the difference of mechanical strength between Panavia F resin cement and self-made resin cement,DESIGN, TIME AND SETTING: A controlled observational study was performed in the prosthesis laboratory of the FourthMilitary Medical University of Chinese PLA between May 2006 and March 2007.MATERIALS: Panavia F resin cement was sourced from KURARAY MEDICAL INC. (Japan), experimental resin cement wasproduced by College of Stomatological Medicine in the Fourth Military Medical University of Chinese PLA.METHODS: Five cylindrical compressive strength specimens at an 8-mm height and 4-mm diameter were prepared, as well as5 cylindrical diametral tensile strength specimens at a 3-mm height and 6-mm diameter. AGS-500 universal material testingmachine was applied to detect the compressive strength and diametral tensile strength.MAIN OUTCOME MEASURES: The diametral tensile strength test and compressive strength test of the specimens.RESULTS: The compressive strength of Panavia F resin cement was remarkably higher than that of experimental cement[(238.92±24.54), (149.08±12.13) M Pa, P ＜ 0.05]. There were no significances between two resin cements on diametral tensilestrength (P＞ 0.05).CONCLUSION: There were no significance between two resin cements on diametral tensile strength following completecuring. The compressive strength of experimental resin cement can reach the standard of ADA (＞ 70 MPa) although it is lowerthan the compressive strength of Panavia F resin cement.

Objective To investigate the expression and significance of B lymphocyte stimulator (Blys) and its receptor BAFF (BAFF-R) in peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE). Methods The expression of Blys and BAFF-R was measured by flow cytometry in 90 pa-tients with SLE,which was compared with that of 45 healthy controls. The relationships between the expression of Blys, BAFF-R and other laboratory parameters as well as disease activity were analyzed. Results The expression of Blys and BAFF-R in PBMCs from patients with SLE was significantly elevated compared to healthy controls (P <0.001), so did the active group (P < 0.001) and inactive group (P < 0.001 and P < 0.01). The expression of Blys in PBMCs from active SLE patients was higher than that of inactive patients (P <0.05). However,there was no statisti-cal difference of BAFF-R between the two groups. The expression of Blys in PBMCs was positively related to SLEDAI (r =0.728,P <0.001) ,IgG and IgM(r=0.691,P<0.001 and r =0.453,P<0.01) ,but negatively related to C3 and CA (r = -0.510, P < 0.001 and r = -0.312, P < 0.05). The expression of Blys in dsDNA positive group was higher than those of dsDNA negative group (P < 0.01). The expression of Blys and BAFF-R in Cl qAb positive group was higher than those of ClqAb negative group as well (P <0.01). Conclusion The expression of Blys and its receptor BAFF-R in PBMCs from SLE is elevated ,which may reflect the disease activity and is related to the pro-duction of autoantibody. They might be involved in the pathogenesis of SLE.

Objective To analyze the correlation between serum anti-C1q antibody (anti-C1q Ab)and renal pathological characteristic,disease activity as well as some laboratory tests in patients with lupus nephritis (LN).Methods Serum anti-C1q antibodies were detected by enzyme-linked immunosorbant assay ELISA) in 120 patients with systemic lupus nephritis (SLE),which included 60 LN patients and 60 non-LN patients.Renal biopsy was conduted in all LN patients.The relationships between serum anti-C1q Ab level and renal pathohistology,lupus nephritis activity,as well as some laboratory parameters were analyzed.Results The mean level of serum anti-C1q Ab in LN patients was (89+26) U/ml,significantly higher than that of nonLN patients (57±23) U/ml (P＜0.01).Twelve cases of renal biopsies were classified as WHO Class Ⅱ,fourteen cases Class Ⅲ,eighteen cases Class Ⅳ,and sixteen cases Class Ⅴ.Significant difference of serum anti-C1q Ab level between each class was found by ANOVA test,and serum anti-C1q Ab level of Class Ⅳ was the highest (P＜0.01).Renal biopsies showed a positive correlation between serum anti-C1q Ab level and activity index of renal pathohistology (P＜0.01).Renal deposition of C1q was related with the level of serum anti-C1q Ab.Serum anti-C1q Ab level was positively correlated with proteinuria (P＜0.01),and negatively correlated with levels of C3 and C4 (P＜0.01).Mean level of serum anti-C1q antibody in SLE patients with positive antidsDNA was higher than that in the patients with negative anti-dsDNA (P＜0.01).Conclusion Serum antiC1q Ab level is significantly associated with lupus nephritis activity and renal pathohistology.It is a useful marker to predict renal lesion and disease activity in lupus nephritis.

BACKGROUND: Irradiation therapy in the cancer patients after surgery may have negative effects on implant fixation. OBJECTIVE: To observe the effects of 60Co irradiation and trace element zinc on fixation strengths of titanium implant. METHODS: Thirty-six adult male rabbits were involved. One piece of titanium implant was separately placed into the bilateral proximal tibial heads in rabbits to set up animal models of titanium implants. The animals were randomly divided into control group, zinc supplement group, 60Co irradiation group and 60Co irradiation and zinc supplement group. Zinc sulfate of 10 g/L was administered intramuscularly to animals in the zinc supplement group at the dose of 4 mg/kg once per day, and those in the control group were treated with saline at the same dose. The animals in the 60Co irradiation group received 60Co irradiation at the dose of 45 Gy and saline by intramuscular injection. Those in the 60Co irradiation and zinc supplement group received 60Co irradiation and zinc sulfate. The animals were killed at 1, 4 and 12 weeks after treatment. The fixation strengths were measured and compared among groups. RESULTS AND CONCLUSION: (1) Zinc supplement made the titanium implants have higher fixation strengths, and reach a high level at 4 weeks after surgery. (2) 60Co irradiation significantly inhibited the fixation strengths of the implants. After 60Co radiation, zinc supplement stil could promote fixation strengths of titanium implants. (3) It is indicated that amount of zinc supplement after irradiation therapy can al eviate the negative effects of irradiation on implant fixation.

Animals ; Embryonic Stem Cells ; metabolism ; Histone Deacetylase 6 ; deficiency ; genetics ; metabolism ; Mice ; Reproduction ; genetics