Effect of salmon calcitonin on RANK/RANKL/OPG osteolysis pathway in human macrophages after particle induction / 中国医师杂志

Objective To explore the effect of salmon calcitonin on the receptor activator of NF-κB/receptor activator of NF-κB ligand/osteoprotegerin (RANK/RANKL/OPG) osteolysis pathway in human macrophages after particles induction.Methods The polyethylene wear particles were extracted from the periacetabular boundary membrane tissue of a patient with hip prosthesis loosening.The optimal reaction cell concentration of human macrophages to polyethylene wear particles (with a concentration of 0.1 mg/ml) was measured by methyl thiazolyl tetrazolium (MTT) assay.Particles were used to stimulate human macrophages,while salmon calcitonin with different drug concentrations was used for intervention.They were randomly divided into five groups,with six parts in each group:Group A,control group;Group B,particle group;Group C,particle + salmon calcitonin (10-8 mol/L) group;Group D,particle + salmon calcitonin (10-10 mol/L) group;Group E,particle+salmon calcitonin (10-12 mol/L) group.After cocultured for 48 hours,quantitative polymerase chain reaction (qPCR) assay was used to detect the mRNA expression of RANK,RANKL and OPG in macrophages.Results After induction with particles,Group B had a higher expression in RANK and RANKL,and lower OPG expression than Group A.After salmon calcitonin intervention,the expression of RANK and RANKL were significantly decreased,and OPG expression was significantly increased.Group B had the highest RANKL/OPG rate.After drug intervention,the RANKL/OPG rate in C,D,E group were reduced.Conclusions The particles can induce the transformation of macrophages into osteoclasts.In addition to directly inhibiting osteoclast activity,salmon calcitonin prevents macrophage from differentiating into osteoclasts through modulating RANKL/RANK/OPG signaling pathway.

Research Progress on Hierarchical Structure of Cortical Bone and Its Toughening Mechanisms / 医用生物力学

Cortical bone is a kind of natural biological composite materials, which is mainly composed of tropocollagen molecules and nanoscale hydroxyapatite mineral crystals. It possesses high strength, stiffness and fracture toughness and has the ability to tolerate damage and self-heal. In the long process of evolution, bone tissues form the biomechanical strength and toughness to meet its functional needs. The excellent mechanical properties of cortical bone are closely related to its hierarchical microstructure. This paper reviewed the hierarchical microstructure of cortical bone and its toughening mechanisms, which would contribute to understanding the diagnosis, prevention and treatment of aging-related osteoporosis and the pathological mechanism of bone diseases.

Research progress of bone microarchitecture and microdamage detection / 中国组织工程研究

BACKGROUND:Bone fragility and poor bone quality due to osteoporosis are a major and increasing concern. Bone microarchitecture and microdamage, the important factors of bone quality, their detection technology and instrument have experienced a long development process. OBJECTIVE:To give a brief introduction of the concept of the bone microarchitecture and microdamage, then to summarize the research progress of their detective methods. METHODS:PubMed and CNKI databases were retrieved for reviews and articles related to bone microarchitecture and microdamage published from January 1990 to June 2016 using the keywords of“bone microarchitecture, bone microdamage and detect/detective/detecting”in Chinese and English, respectively. Finaly a total of 65 articles were selected for overview. RESULTS AND CONCLUISON:(1) Bulk staining is a quick and useful way to confirm and assess linear microcracks and diffuse damage. Micro-CT and confocal microscopy al ow visualization at the micron scale, and are useful tools to understand the three-dimentional nature of bone microdamage. Scanning electron microscope lacks the ability to investigate large regions of microdamage, but al ows users to probe in extensive details at the nano scale. (2) Ultimately, we recommend the use of multiple imaging modalities according to the experimental needs to obtain useful information about bone quality and microdamage formation, across the scales of hierarchy in bone.

Correlation between C-reactive protein and pain in periprosthetic infection after total hip arthroplasty / 中南大学学报(医学版)

OBJECTIVE@#To explore the difference in level of pain experienced by patients with total hip arthroplasty between aseptic loosening and periprosthetic infection, and to examine the correlation between C-reactive protein (CRP) and pain.@*METHODS@#Fifty-one patients (recruited from our hospital between March 2010 and November 2011) suffering aseptic loosening or periprosthetic infection after total hip arthroplasty were included in this study: 24 males and 27 females, with mean age 68.13 years. The patients were divided into an aseptic loosening group (n=31) and a periprosthetic infection group (n=20). Both the visual analog scale (VAS) and Harris pain score were used to estimate the level of pain experienced by the patients. CRP levels in serum were measured. The difference in assessment of pain by VAS and Harris pain score was compared between the two groups, and the correlation between pain and CRP was analyzed.@*RESULTS@#The mean VAS in the aseptic loosening group was 5.39 (2.10-8.13) compared with 5.48 (2.09-8.30) in the periprosthetic infection group; however, the difference was not statistically significant (P=0.85). The mean rank of Harris pain score was 26.23 in the aseptic loosening group and 25.65 in the periprosthetic infection group, but again there was no significant difference (P=0.88). The CRP level in the periprosthetic infection group (36.20-101.40 mg/L, mean 72.86 mg/L) was obvious higher than that in the aseptic loosening group (1.37-13.70 mg/L, mean 6.53 mg/L), and the difference was statistically significant (P<0.01). The VAS was related with the CRP level in the periprosthetic infection group (r=0.87, P<0.01), and the correlation between Harris pain score and CRP level was conspicuous (r=0.92, P<0.01) in this group. However, those correlations were not evident in the aseptic loosening group (r=0.25, P=0.17; r=0.19, P=0.65).@*CONCLUSION@#There is no difference in perception of pain in patients after total hip arthroplasty between those with aseptic loosening and those with periprosthetic infection. It is therefore unreliable to make a initial diagnosis only according to the level of pain. However, the level of CRP is a sensitive and effective way of differentiating the two conditions. The positive correlation between CRP and pian exists in patients with periprosthetic infection but not with aseptic loosening.

Comparison of mechanical properties between vital dentine and pulpless dentine / 实用口腔医学杂志

Objectives:To study the mechanical properties of human dentin obtained from vital and pulpless teeth. Methods:Dentin specimens were obtained from 20 freshly extracted normal vital human teeth and 9 endodontically treated human pulpless teeth. The dentin was grinded to be rectangular specimens along to the longitudinal axes of the teeth. All the specimens were immerged in 9 g/L sodium chloride solution, their compressive mechanical properties were measured with displacement measurement method. All data obtained were analyzed with t tests. Results:The elastic moduli,proportional limits and compressive strengths of the dentin samples from vital teeth were (15.77? 1.52 ) GPa, (157.07?13.79) MPa and (257.67?10.23) MPa respectively. Those from pulpless teeth were (12.08?1.71) GPa, (144.30?9.76) MPa and (235.26?9.12) MPa respectively(P

Regulation of cyclosporin A on nm23-H1 expression in human trophoblast / 中国病理生理杂志

AIM:To explore whether cyclosporine A (CsA) can regulate the expression of nometastatic gene23 H1 type (nm23-H1) in human choriocarcinoma Bewo cells,in order to seek new proof of treating trophoblast diseases.METHODS:The Bewo cells were divided into two groups. The vehicle control group,and the CsA group with different concentrations from 10-2 ?mol/L to 10 ?mol/L. The effect of CsA on the transcription of nm23-H1 was determined by reverse transcription-polymerase chain reaction (RT-PCR) after cultured for 48 h and protein level of nm23-H1 was determined by In-cell Western after cultured for 72 h.RESULTS:Compared to the vehicle group,CsA significantly downregulated the transcription and translation of nm23-H1 in a dose-dependent manner from 10-2 ?mol/L to 10 ?mol/L,and the inhibition reached its top when concentration of CsA was 1.0 ?mol/L (P