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We review the representatives literatures on chronic osteomyelitis, sum up the new insights in recent years into diagnostic options and treatment regimens, analyze the advantages and disadvantages of various diagnostic approaches and treatment strategies, and propose areas of interest to make current diagnostic and treatment strategies more specific.
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BACKGROUND: It is an urgent problem to effectively make bone marrow mesenchymal stem cells exert proper effects under hypoxic preconditioning. OBJECTIVE: To investigate the effects of diazoxide, a Mito-KATPchannel activator, on the proliferation and apoptosis of mouse BMSCs in hypoxic environment. METHODS: Mouse BMSCs were divided into four groups: blank control group, 0.16, 0.8, 4 μmol/L diazoxide groups. Cells intervened by diazoxide were cultured in a 10% O2incubator. MTT assay was performed to detect cell proliferation at 1, 2, 4, 6, 8 days after intervention, and Hoechst 33258 staining was performed to observe cell apoptosis at 14 days after intervention. RESULTS AND CONCLUSION: High homogeneity and purity but low proliferation of BMSCs was found. There was no significant difference in the activity of BMSCs among 0.16, 0.8, 4 μmol/L diazoxide groups (P > 0.05). In the blank control group, concentrated nuclei were dark blue in color and aggregated, and several round apoptotic bodies were found. In the diazoxide groups, apoptotic bodies were occasionally found, and no significant difference was found among different diazoxide groups. These findings indicate that a certain concentration of diazoxide can reduce cell apoptosis but has no effects on the proliferation of mouse BMSCs under hypoxic environment (10% O2).
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BACKGROUND:β-tricalcium phosphate (β-TCP) and monocalciumphosphate monohydrate (MCPM) are traditionally considered as reactants for dicalcium phosphate dehydrate (DCPD) bone cement,but little is reported on the hydroxyapatite (HA) as a reactant.OBJECTIVE:To verify whether HA and MCPM can be used to prepare DCPD bone cement and to explore the physicochemical properties.METHODS:The HA and β-TCP were prepared by wet chemical precipitation method,and mixed with appropriate proportion of MCPM.Then,the HA-DCPD and β-TCP-DCPD were obtained by adding a proper amount of curing water.The composition and structure of the two materials were analyzed by X-ray diffraction,the morphology was observed by scanning electron microscope,and the mechanical strength was tested by Instron5567 universal material test machine.These two kinds of materials were placed in simulated body fluid for detecting the weight loss ratio,soaked for 14 days and taken out for X-ray diffraction and scanning electron microscope detection.RESULTS AND CONCLUSION:X-ray diffraction findings indicated that these two kinds of materials both belonged to high-purity DCPD bone cement.Under the scanning electron microscope,β-TCP-DCPD bone cement had dense crystal structure,with less pore number;however,the HA-DCPD bone cement presented with finer grains,loose structure,and higher pore number.With the increase of curing time,the mechanical strength of two kinds of bone cements was correspondingly increased,but the compressive strength of β-TCP-DCPD bone cement was significantly higher than that of HA-DCPD bone cement (P ＜ 0.05).In the simulated body fluid,the weight loss ratio of β-TCP-DCPD bone cement was significantly lower than that of HA-DCPD bone cement (P ＜ 0.05).At 14 days after soaking in the simulated body fluid,a layer of spherical particles that was formed on the surface of both materials was identified as hydroxyapatite by scanning electron microscope observation and X-ray diffraction analysis.In summary,HA-DCPD bone cement has good biodegradability,excellent bioactivity and bone conductivity,but poor mechanical properties.