0.05).The size of PCR fragments ranged from 144 to 188bp containing 19～41 CA repeats and the frequency of (CA)n ranged from 0.34%～14.1%.The heterozygosity(H) and polymorphism information content(PIC) were 0.85 and 0.83 respectively.Significant differences were found in frequencies of eleven alleles including 22-repeats,23-repeats,26-repeats,27-repeats,28-repeats,30-repeats,31-repeats,32-repeats,33-repeats,34-repeats and 35-repeats between Chinese and Caucasians.Conclusion:This site is referred to as a genetic marker with high polymorphism information content.And the distribution of this genetic marker is different in different ethnic groups.

Background and purpose:The screening of the genes being related closely with the mechanism of osteosarcoma metastasis was a difficult point in the realm of orthopaedics.We screened differential expression gene of human osteosarcoma MG-63 cell sublines with different metastatic capabilities with cDNA microarray,and studied the molecular mechanism of osteosarcoma metastasis.Methods:Total RNA of human osteosarcoma MG-63 cell sublines A1 and A2 was extracted,purified to mRNA and then reversely transcripted to cDNA probe respectively.The cDNA probe of A1 was labelled with Cy3 and the cDNA probe of A2 was labelled with Cy5.The two samples were hybridized with the cDNA microarray.The hybridization signals were scanned by Agilent Scanner and obtained data were analyzed using Ima Gene 3.0 software and Genespring software.Results:222 differential expression genes were found between cell sublines A1 and A2 by analyzing gene expression profile.There were 119 upregulated genes and 103 downregulated genes in cell sublines A1.All differential expression genes belonged to six main function groups and 49 genes of these had very obvious differentce in expression.Conclusions:There were many differently expressed genes between A1 and A2 cell sublines and only part of them were closely associated with mechanism of osteosarcoma metastasis.The technology of cDNA microarray could analyze effectively gene expression profile of human osteosarcoma MG-63 cell sublines, and supply a new approach to study the mechanism of osteosarcoma metastasis

[Objective]To investigate the relationship between degeneration of cartilage and the expressions of Matrix Metalloproteinase 7(MMP-7),Matrix Metalloproteinase 9(MMP-9),Matrix Metalloproteinase 13(MMP-13)and Tissue Inhibitor of Matrix Metalloproteinase 1(TIMP-1)in osteoarthritis.[Method]The histological changes of cartilages by hematoxyllin-eosin staining and immunohistochemical expression of Matrix Metalloproteinase 7(MMP-7),Matrix Metalloproteinase 9(MMP-9),Matrix Metalloproteinase 13(MMP-13)and Tissue Inhibitor of Matrix Metalloproteinase 1(TIMP-1)in osteoarthritis.were studied in 20 osteoarthritis cases and 2 normal controls.All data were statistically analyzed by Mann-Whitney U test and correlation analysis.[Result]The osteoarthritis cartilage underwent fibroplasias and tearing.The quantity of chondrocyte increased and the clustered and hypertrophic cells came into being.Little immunostaining of MMP-7 and MMP-13 was observed in normal cartilage,while their expressions increased in degenerated cartilage(P0.05),superficial layer of the moderate and end-stage osteoarthritis.However,it significantly increased in deep layer(P

[Objective] To study the bone metabolic biochemical index of the aged patients with hip fracture,for better predicting the future risk of the old people' s hip fracture.[Method]50 cases of sufferers(over 60 years old) with hip fracture(28 males,and 22 females) and 30 cases of healthy aged people(15 males,and 15 females) were selected to analyze Ⅰ Collagen crosslinked c-telopeptide(ICTP),deoxypyridino line(Dpd) in urine,and serum bone glaprotein(BGP).[Result](1)The mean level of ICTP and Dpd in urine in aged hip fracture group was higherthan that of the control group(P0.05).[Conclusion]Bone absorbability in the aged hip fracture patients is higher than in the aged healthy people.The analysis of ICTP and Dpd in urine may /might give some reference value in preventing and treatlng aged hip fracture patients.

[Objective]To prove the feasibility of using the distance between sagittal plane of the spinal process and the enter point to individualize the placing of pedicle screw.[Method]Thirty spine specimen were collected and divided into two groups,data were measured,such as the width of the pedicle,distance between the enter point and anterior border of the vertebra,distance between sagittal plane of the spinal process and the enter point,angle from the longitudinal axis of the pedicle to sagittal axis of the vertebra,angle from the longitudinal axis of the pedicle to vertical line of the operating table.In group one the pedicle screws were placed with the help of the distance between sagittal plane of the spinal process and the enter point,the other by the method advised by Ebraheim.CT scan was applied to evaluate the place of the screws,according to the perforation extent,they were classified into 4 grades:A=totally in the pedicle;B=perforation extent4mm.[Result]The individualized group showed much lower perforation rate than the traditional method group in T3~10,and similar in T1,T2,T11,12.[Conclusion]It can obviously improve the accuracy of the pedicle screw placement to use the distance between sagittal plane of the spinal process and the enter point to localize the enter point,especially when anatomic landmark such as articulationes zygapophysiales and transverse process change.

Objective To screen promoter DNA-binding protein of inducible nitric oxide synthase gene by using phage display technique from human liver cDNA library, and to study the expression and regulation mechanism of iNOS gene. Methods The sequence of iNOS promoter was identified in GenBank by bioinformatics based on the open reading frame(ORF) of iNOS gene and amplified from HepG2 genome by polymerase chain reaction (PCR). The amplified product was subcloned into pCAT3-Basic reporter vector, named as pCAT3-iNOSp. The HepG2 cell line was then transfected with pCAT3-Basic to serve as negative control, and pCAT3-promoter which contains the promoter region of CMV served as the positive control subject, and pCAT3-iNOSp served as the test subject, respectively. The choloraphenical acetyltransferase(CAT)activity was determined by enzyme linked immunosorbent assay(ELISA) kit. The T7 Select human liver cDNA library was biopanned and positive clones were selected. After screening, positive plaque was performed to amplify and PCR products were sequenced. Results The expression of CAT in transfection of pCAT3-PS1TP1p was 4.2 times as higher as pCAT3-Basic plasmid. Sequence analysis was performed in 12 positive plaque, which were the iNOSp binding protein. Conclusion The iNOS gene promoter identified in this study has shown to have transcription activity,and iNOS promoter DNA-binding proteins havs been screened. The results will be useful for further study of the expression and regulation mechanism of iNOS in liver cell.

PBL,problem based learning,is a kind of teaching model for resolving problems. Based on the present teaching situation of our university,my experience in NewYork University and my teaching experience for overseas students,this article elucidated the importance and necessity of PBL teaching model in overseas student education and put forward a suitable PBL teaching method.

The present paper is aimedto investigate the effect of basic fibroblast growth factor (bFGF) on proliferation, migration and differentiation of endogenous neural stem cell in rat cerebral cortex with global brain ischemia-reperfusion. A global brain ischemia-reperfusion model was established. Immunohistochemistry was used to observe the pathological changes and the expression of BrdU and Nestin in cerebral cortex. RT-PCR was used to measure the NSE mRNA in brain tissue. The results of measurements indicated that in sham operation group, there was no positive cell in cerebral cortex, and the content of NSE mRNA did not change. In the operation group, the expression of BrdU and Nestin increased significantly at the end of the 3rd day, and peaked on the 7th day. NSE mRNA expression did not significantly increase. In bFGF group, compared with sham operation group and model group, the number of BrdU-positive and Nestin-positive cells increased significantly at each time point (P<0. 05), and peaked at the end of the 11th day, and the content of NSE mRNA increased significantly (P<0. 05). This research demonstrated that the proliferation of endogenous neural stem cells in situ could be induced by global cerebral ischemia and reperfu- sion, and could be promoted and extended by bFGF. In additiion, bFGF might promote endogenous neural stem cells differentiated into neurons.
Animals ; Brain Ischemia ; pathology ; Cell Differentiation ; Cell Movement ; Cell Proliferation ; Cerebral Cortex ; cytology ; metabolism ; pathology ; Fibroblast Growth Factor 2 ; pharmacology ; Nestin ; metabolism ; Neural Stem Cells ; drug effects ; Rats ; Reperfusion Injury

X-box binding protein1 (XBP1) is an important transcription factor, which participates in many signal transduction procession.To investigate the biological function of XBP1, yeast two-hybrid system to screen proteins interacting with XBP1 in hepatocytes was performed. The XBP1 coding sequence was amplified by polymerase chain reaction (PCR) method, and was cloned in pGEM-T vector. After the target region was sequenced, it was subcloned into the bait plasmid pGBKT7, then was transformed into yeast AH109(a type). After the expression of bait plasmid pGBKT7-XBP1 in AH109 yeast strains were proved by Western blot. The transformed yeast AH109 was mated with yeast Y187(α type) containing hepatocyte cDNA library plasmids pACT2 in 2 ×YPDA medium. Diploid yeast was plated on synthetic dropout nutrient medilium (SD/-Trp-Leu-His-Ade) containing X-α-gal for selection and screening. After sequencing and verifying ORF of positive colonies,7 different kinds of proteins were obtained. In order to further testify the interaction between the screened proteins and XBP1, one of positive colonies MT1E was cloned. The interaction between MT1E and XBP1 in vitro/in vivo were examined successfully with GST pulldown and coimmunoprecipitations. It was shown that MT1E would be a new regulatory protein of XBP1. These screened proteins by yeast two-hybird system were closely correlated with liver fundamental metabolism,protein synthesis and transport,cell proliferation and apoptosis. The results mentioned above contributed to reveal the XBP 1 biological function, and brought some new clues for further exploration of the expressing and regulating mechanism of XBP1.

Objective To investigate the effect of calcitonin gene-related peptide ( CGRP ) in inducing os-teogenic differentiation of rat precartilaginous stem cells in vitro and the underlying mechanisms. Methods Rat pre-cartilaginous stem cells ( PSCs) were cultured in complete osteogenesis medium containing DMEM/F-12 medium and different concentrations (0, 10-8,10-9,10-10mol/L) of CGRP, the morphology changes of PSCs were observed. The proliferation of PSCs was examined at different time points by CCK-8. All the PSCs were then randomly assigned to an experimental group and a control group. The PSCs in the experimental group were cultured in complete osteogenesis medium with 10-10 mol/L CGRP , while the control group cultured merely in complete osteogenesis medium was re-ceived no special intervention. Both groups were stained by Alizarin Red and the expression of alkaline phosphatase (ALP) was detected. The osteogenic genes (RUNX2,OPN and BGP) were measured by use of RT-PCR. The activa-tion of Wnt/β-catenin signaling pathway was tested by using Western blotting to evaluate the effect of CGRP . Results Compared to the control group ( the concentration of CGRP was 0 mol/L) , the concentration of ALP was significantly higher in the experimental group, calcium deposition was significantly more obvious, and the expression of the osteogenic genes such as RUNX2,OPN and BGP as well as theβ-catenin protein expression were up-regulated significantly. However, CGRP had no effect on cell proliferation. Conclusion CGRP activated Wnt/β-catenin sig-nal pathway and induced osteogenic differentiation of precartilaginous stem cells.