Objective To study the impacts of dynamic compressive stress on the mRNA expression of osteopontin ( OPN ),runt related gene 2 ( Runx2 ),osteocalcin ( OC ),osterix,alkaline phosphatase (ALP) and bone morphogenetic protein 2 (BMP-2) in the osteoblasts of Sprague-Dawley (SD) rats. Methods Osteoblasts extracted from skull periosteum tissue of neonatal SD rats were digested using trypsin and collagenase （Ⅰ）,then were subcultured and amplified in vitro.ALP staining and alizarin red staining were performed to identify the purified cells.The cells were treated with compressive stress at 20,50 or 100 mmHg for 24 h.The expression levels of OPN,Runx-2,OC,osterix,ALP and BMP-2 were measured and quantitatively analysed using a real-time quantitative polymerase chain reaction. Results Under 20 mmHg of dynamic compressive stress the expression levels of OPN,Runx2,OC,osterix,ALP and BMP-2 all were elevated compared with the control group.The peak expression oecured under 50 mmHg pressure. The expression levels did not change significantly compared with the control group under 100 mmHg pressure. Conclusions Moderate dynamic compressive stress can promote the expression of OPN,Runx-2,OC,osterix,ALP and BMP-2 mRNA in osteoblasts,which might be an important mechanism for promoting the union of fractures.

This study examined the effect of small interfering RNA-mediated β-catenin knockdown on the survival, invasion and chemosensitivity of human osteosarcoma cells (U2-OS cells). The siRNA against β-catenin was constructed and transfected into U2-OS cells. The expression of β-catenin was detected by qRT-PCR and Western blotting. Cell growth and apoptosis was detected in the presence or absence of doxorubicin by MTT and flow cytometry, respectively. Cell invasion ability was measured by transwell assay. The results showed that the transfection of β-catenin siRNA resulted in decreased expression of β-catenin, suppression of invasion and motility of U2-OS cells, reduced chemosensitivity to doxorubicin in vitro, and little change in cell growth and apoptosis. Additionally, down-regulated MT1-MMP expression was found after transfection. It was concluded that knockdown of β-catenin gene may decrease the invasive ability of human osteosarcoma cells through down-regulated MT1-MMP expression, and the chemosensitivity of osteosarcoma cells against doxorubicin.

Objective To investigate the changes of excitatory amino acids (EAAs) of cerebrospinalfluid (CSF) in patients with delayed encephalopathy after acute carbon monoxide poisoning(DEACMP).Method The EAAs levels of CSF including glutamate (Glu) and aspartate (Asp) in 24 patients with DEACMP and 20 controls with migraine were measured by high performance liquid chromatography( HPLC ).Results Glu and Asp levels in patients with DEACMP were significantly higher than those of the controls [(3.76 ± 1.52) μmol/L vs ( 1.55 ± 1.03 ) μmol/L, (0.73 ± 0.44) μmol/L vs (0.38 ± 0.33 ) μmol/L, P all <0.01]. Glu and Asp levels in moderate and severe DEACMP patients were higher than those in mild DEACMP patients. Conclusion It suggests that EAAs participated in the pathogenesis of DEACMP. The Glu and Asp levels in CSF may be regarded as indicator of DEACMP.

To explore the experience in teaching of interns in orthopedic,we put emphasis on the knowledge teaching of medical ethics and medical dispute in addition to the teaching of expertise of orthopedic.

Objective To investigate the effect of 620 nm red light on chondrogenic differentiation in rat precartilaginous stem cells (PSCs). Methods Rats' PSCs were isolated and purified using magnetically activated cell sorting and cultured in vitro.The PSCs were exposed once to 620 nm wavelength red light from a light-emitting diode (LED) with an irradiation energy of 0.5 J/cm2,1 J/cm2,2 J/cm2 or 4 J/cm2.Any effect was confirmed by Alcian blue staining,immunohistochemistry and observing histomorphological changes under a light microscope,as well as detection using a reverse transcription polymerase chain reaction (RT-PCR). Results After being induced for 14 d,the PSCs exhibited polygonal and round shapes. Alcian blue and type Ⅱ collagen immunohistoehemistry staining showed positive results,but the control group had no significant change.RT-PCR showed that the mRNA expression of Sox9 and type Ⅱ collagen increased significantly compared with the control group. Conclusion Low energy 620 nm red light can enhance chondrogenic differentiation in PSCs significantly.

BACKGROUND: Biodegradable internal fixation devices have been used in clinics. However, they can only be used for internal fixation of non weight-bearing bones. A new kind of biodegradable internal fixation device with high initial strength and slow early degradation, which can be used for weight-bearing bones, is required.OBJECTIVE: To test the initial strength and observe the degradation of human hair polylactic acid (HHPLA) composite rods.DESIGN: Repeated measurement designSETTING: Center of Orthopaedic Department, Zhujiang Hospital, Southern Medical University; Department of Human Anatomy of Southern Medical UniversityMATERIALS: The experiment was conducted in the Southern Medical University between September 2002 and October 2003. Totally 54 adult SD rats were recruited.METHODS: ①The shear strength, the bending strength and the bending modulus of 20 HHPLA composite rods were tested with the biomechanical testing system (MTS-858 Mini Bionix) to investigate the initial nechanical feature of HHPLA composite rods. ②A total of 108 samples of HHPLA composite rods, which were developed for internal fixation of fracture, were randomly implanted in bilateral dorsal subcutaneous tissue of 54 SD rats and taken out at weeks 1, 2, 4, 8, 12, 16, 20, 24 and 28 (6 rats at each time point). The weight losses were measured to understand the degradation of HHPLA composite rods in SD rats.MAIN OUTCOME MEASURES: ①Mechanical strength of HHPLA composite rods. ②Degradation in vivo of HHPLA composite rods.RESULTS: Totally 54 rats entered the result analysis. ①HHPLA composite rods has good initial mechanical strength. Its shear strength of the HHPLA rod was 241 MPa, bending strength was 358 MPa, and the bending modulus was 13 GPa. ②HHPLA was fairly degradable in SD rats.Degradation was slower in the earlier period than that in the later period.CONCLUSION: HHPLA composite rods have some fairly good characteristics of initial mechanical strength and degradation in vivo.

Object To demonstrate the naked truth of four therapeutic features of TCM (cold, hot, warm and cool) from biophysical and biochemical point of view. Methods Growth thermogenesis curves of Escherichia coli were determined under different conditions by microcalorimetry to give biothermodynamic parameters, such as multiplication constant (k), median inhibitory concentration (IC 50 ), and enthalpy (?H). Differences between folia ginseng and flos ginseng were comprehensively compared with reference to classical Chinese literatures on material medica. Results The bacteriostatic curve of both drugs were basically similar. With increasing concentration of decoctions of both drugs, the lag phase was delayed and the peaks shifted to the right. While the difference of ?H was stable, which decreases with the increasing concentration of Folium ginseng, but increases with increasing concentration of Flos ginseng. Conclusion Microcalorimetry is not only a new effective method to describe the therapeutic features of TCM, but also could be used as a tool for the screening of active TCM.

This study was aimed to discuss the dynamic variation of soluble sugar contents, sucrose metabolizing en-zyme activities and gene expression quantities during the fruits development of A momum villosum, in order to pro-vide the basis of improvement of the fruit yield. Fresh fruits at three different development processes (30 DAF, 60 DAF, 90 DAF) were used to investigate changes of soluble sugar components and sucrose metabolizing enzyme activ-ities by HPLC and UV spectrophotometry. Combining with the high-throughput sequencing expression profile data of three fruit development period, the trends of three key enzymes gene expressed in sugar metabolism were analyzed. The results showed that the fruit sugar components were dominated by fructose, glucose and sucrose. The concentra-tion of hexose (fructose and glucose) gradually decreased in peel. But in seeds the concentration of hexose decreased at first and then increased. The content of sucrose and the net activities of sucrose synthase (synthesizing direction minus decomposing direction) in peel and seeds were gradually increased. The expression trends of key enzyme gene in sugar metabolism examined by RNA-seq quantification showed that sucrose phosphate synthase and sucrose syn-thase gene increased and then kept constant, but the invertase gene expression trend was gradually rising. Conse-quently, sucrose synthase was the key enzyme catalyzing sucrose synthesis and decomposition. The activity of sucrose synthase and sucrose contents in peel and seeds reached the highest peak in the end of fruit mature.

Objective To identify the reliable reference genes for gene expression analysis of the pericarp and seed of Amomum villosum Lour. by using real-time fluorescence quantitative polymerase chain reaction ( qRT-PCR). Methods Using the fruits ( separated into peels and seeds) of A. villosum at three different developmental periods as the experimental material, 5 candidate reference genes (β-actin, EF-1α, GAPDH, PGK, TUA) with steady expression were screened out by the high throughout sequencing of transcriptome and expression profile data. The qRT-PCR technique was applied to study the expression levels of 5 candidate reference genes in different samples. The stability of the candidate reference genes were evaluated by GeNorm and NormFinder software. Results The 5 reference genes had different stabilities in the pericarp and seed of A. villosum Lour. at different development periods . The order of the steadiness of reference genes showed by GeNorm was EF-1α = TUA>PGK>GAPDH>β-actin. The results of NormFinder revealed that EF-1α was the most stable, followed by TUA, and the order of the other three genes was as same as the results of GeNorm. Conclusion EF-1αand TUA could be used as double reference genes for the normalization of gene expression in A. villosum fruits at different developmental periods by using qRT-PCR.

Objective To observe the effects of different concentrations of glucose on the proliferation and differentiation of primary osteoblasts.Methods The identification of mouse primary osteoblasts was performed by alkaline phosphatase (ALP)staining and Von Kossa staining.Treating osteoblasts with different dose of glucose (5.5,15.5,25.5 mmol/L),the osteoblasts proliferation,ALP staining,and Runx2,OB markers ALP and OCN mRNA expression were observed.Real-time PCR was used for the determination of Runx2,OB markers ALP and OCN mRNA expression.Results With the increasing glucose concentrations,the osteoblasts cell proliferation was decreased.Compared with 5.5 mmol/L normal glucose,the ALP staining in 15.5 mmol/L group and 25.5 mmol/L group were decreased.The expressions were decreased by (36.7±6.2)％ and (38.3±2.2)％ in Runx2 mRNA,(26.7±7.2)％ and (40.4±4.3)％ in OCN mRNA respectively.ALP in 15.5 mmol/L group was reduced by (33.3±10.2)％,but increased by(50.8±10.4) ％ in 15.5 mmol/L group.Conclusions High glucose may decrease osteoblasts proliferation and activity,which may be one of the key pathogenesis factors of diabetic osteoporosis.