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BACKGROUND:IPS e.max Presshas an excelent biocompati bility and corrosion resistance, which obtains satisfactory clinical outcomes on dental veneers, inlay and onlay restorations. But little is reported on molar monolithic restoration by IPS e.max Presscrown. OBJECTIVE:To evaluate the clinical effects of IPS e.max Press crown on molar repair after root canal therapy. METHODS:Totaly 215 patients with 324 affected molars, including 88 males and 127 females, aged 22-58 years old, were enroled for repairing with IPS e.max Presscrown. Then the color, shape, fracture and edge coloring of the restoration, marginal discrepancy, secondary caries and gingival health status were assessed after a 3-year folow-up. RESULTS AND CONCLUSION:During the folow-up, 324 dental restorations met the class A standards for color, marginal discrepancy, shape as wel as secondary caries. In addition,3restoration swere fractured, 14 restorations had margin coloring, and 8 restorations appeared to have gingival inflammation. More than 95% restorations were scored grade A. These results indicate that IPS e.max Press crown applied to molar repair after root canal therapy can achieve ideal outcomes.
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Objective To explore the effects of extracellular regulated protein kinase 1/2 (ERK1/2) signal pathway on cardiomyocyte apoptosis and tumor necrosis factor-α (TNF-α) expression at different glucose-lowing rates,and the influence of glucose-lowing rate on cardiomyocyte injury and inflammatory secretion function,as well as its mechanism.Methods Cardiomyocytes of Wistar neonate rat were maintained in medium supplemented with 25 mmol/L glucose for 72 h.Then the medium was changed to different concentrations of glucose and all cells were divided into five groups.Group A was control group whose medium supplemented with 25 mmol/L glucose.Medium of group B,C,D,E was supplemented with 20,15,10,5 mmol/L glucose (glucose-lowing rate was 5,10,15,20 mmol/L) respectively.Survival rate of cardiomyocyte was measured by CCK8 kit.Cardiomyocyte apoptosis was measured by flow cytometry instrument and laser confocal microscope after Annexin V-PI.TNF-α was measured by ELISA.ERK1/2 protein and phosphorylation were measured by Western blot.Cardiomyocyte apoptosis and TNF-α levels were measured again after U0126 was added.Results At the same time point,along with the glucose-lowing rate increased,survival rate of cardiomyocyte in group A was increased and those in group C,D,E were decreased (P＜ 0.05).TNF-α concentration was increased in group B,C,D and decreased in group E.After 24 h,apoptosis rate decreased in group B and increased in group C,D,E (P＜0.05).ERK1/2 phosphorylation level increased in group B,D,and E(P＜0.05).The ERK1/2 phosphorylation level in group B was the lowest.After U0126 was added,survival rates of cardiomyocyte in all groups were increased (P＜0.01) while TNF-α concentrations were decreased (P＜0.05).In every group,survival rate of eardiomyocyte after 48 h was lower than that after 3 h and 24 h,while TNF-α concentration was higher (P＜0.05).Conclusion Influence of glucose-lowering rate for cardiomyocyte apoptosis and TNF-o is caused by ERK1/2 pathway.In the glucose-lowering course,ERK1/2 pathway promotes cardiomyocytes apoptosis and TNF-α secretion is related with not only osmotic pressure,but also ERK1/2 signal pathway activation as well.
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BACKGROUND:Vacuolar proton pump on the cytoplasmic membrane of osteoclasts is an essential enzyme for bone histolysis. Vacuolar proton pump inhibitor can significantly inhibit the in vitro cultured osteoclasts. OBJECTIVE:To observe the effect of proton pump inhibitor FR167356 on the osseointegration of dental implant of osteoporosis rabbits. METHODS:A total of 24 female Japanese white rabbits aged 5 months were randomly divided into three groups:ovariectomy (OVX) group, FR167356 group and shamed operation group. Each group contained eight rabbits. Rabbits of OVX group and FR167356 group received a surgical removal of bilateral ovaries, while rabbits of sham operation group had a surgical removal of equivalent adipose tissue beside the ovaries. Two titatium implants (8 mm long, 3.3 mm diameter) were instal ed into bilateral proximal tibias respectively 12 weeks after OVX operation. FR167356 was administrated by muscle injection in FR167356 group;meanwhile equivalent normal saline was administrated in the OVX group and sham operation group. At 4 and 8 weeks after implantation, animals in each group were sacrificed respectively for X-ray imaging, histomorphology, and mechanical test. RESULTS AND CONCLUSION:X-ray examination showed that at 4 weeks, the implants in the OVX group exhibited a high resistance projective image, low density image of clearance screw thread, and clear boundaries between bone tissue than the other two group. At 12 weeks, the density of the clearance screw thread in sham operation group and FR167356 group was more closer to the surrounding bone tissue when compared with the OVX group, the boundaries between the implant and the surrounding bone tissue disappeared more apparently, and no significant differences were found between the two groups. Histomorphology observation revealed that, at 4 weeks after implantation, new bone with porous and trabecular extended along the implant surface to the root direction in FR167356 and sham operation groups. There were no significant differences in the two groups. At 12 weeks after implantation, the bone mass around implant was increased greatly and the trabecular grew thicker. This phenomenon was not observed in the OVX group. Mechanic test showed that at 4 and 12 weeks after implantation, the maximum pul out force in the OVX group was significantly lower than that in the other two groups. Local application of FR167356 can significantly improve the osseointegration of the implant in osteoporosis rabbits.
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BACKGROUND: Because of complicated physiological environment and difficulty to control experimental conditions, it is difficult to get satisfactory results from in vivo studies of cell mechanics.OBJECTIVE: To study the action and mechanism of p38MAPK signaling pathways on myoblast apoptosis based on successful construction of in vitro mechanical stimulation models.METHODS: The C2C12 cells cultured in vitro were divided into control group and SB203580 treatment group. Cyclic tensile stress was applied on the C2C12 myoblast cells for 0, 6, 12 and 24 hours in each group. The Flexcell Strain Unit-5000T was used to expose C2C12 myoblast cell to an equiaxial cyclic of 15% magnitude and a frequency of 10 cycles/min, each cycle including the 3 s stretch and 3 s relaxation. Hoechst 33258 fluorescent staining and optical microscope were used to detect cell apoptosis. RT-PCR, flow cytometric analysis were used to observe the apoptosis of C2C12 myoblast cells and Western blotting were used to detect the activity of p38MAPK and p-p38MAPK. RESULTS AND CONCLUSION: The optical microscope tested the change in the morphology. Hoechst 33258 staining showed that after treatment with cyclic stress, the cell took the typical appearance of apoptosis with chromatin condensation and apoptotic bodies. RT-PCR and flow cytometry showed that with the extension of time the rate of the apoptosis of C2C12 myoblast cell increased. And cells imposed SB203580 before imposing cyclical tensile stress, the results showed that the apoptosis was markedly affected, and the p-p38MAPK expression declined apparently. These findings demonstrate that p38MAPK signaling pathways in stress mediated into C2C12 myoblast cell apoptosis plays an important role.
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BACKGROUND: When the teeth affected abnormal biting force, tooth absorption and periodontium would be greatly damaged. OBJECTIVE: To study whether periodontal membrane fibroblast affected apoptosis following cyclic tensile stress stimulation and whether p38MAPK signaling pathway participated in apoptosis. METHODS: Fibroblasts at passages from 4 to 7 were randomly assigned to control, loading and SB203580 groups after synchronization. In the loading and SB203580 groups, 12% strain was applied at a loading frequency of 6 cycles per minute, i.e. 5 seconds for tension and 5 seconds for relaxation. In the SB203580 group, cells were treated with 20 mmol/L p38MAPK inhibitor SB203580 at 1 hour before loading. At 6, 12 and 24 hours after loading, cells from each group were harvested, and cell apoptosis was detected using a flow cytometry. Expression of bax mRNA was determined using reverse transcription-polymerase chain reaction. RESULTS AND CONCLUSION: Compared with the control group, apoptotic rate of fibroblasts and bax mRNA expression were increased after loading (P < 0.05), and enhanced over time, and peaked at 12 hour following loading, and then decreased gradually. Compared with the loading group, cell apoptosis was reduced at corresponding time points in the SB203580 group (P < 0.05), and bax mRNA expression was diminished. These results indicated that cells affected apoptosis after mechanics stimulation, and mitogen activated protein kinase p38MAPK signaling pathway participates in the process of apoptosis.
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Objective To investigate the C-reactive protein (CRP) concentrations in the pathogenesis of type 2 diabetes mellitus (DM) and its macrovascular complications. Methods Serum CRP levels were assayed by ELISA, which were determined in type 2 DM patients with or without macrovascular complication (88 and 64 cases respectively), non-DM patients presenting with macrovascular disease (72 cases), as well as impaired fasting glucose (IFG) (62 cases) or impaired glucose tolerance (IGT) (70 cases) patients and normal controls (80 subjects). Results In general, CRP levels in IGT patients, type 2 DM patients and non-DM patients presenting with macrovascular disease were higher than those of normal controls (P