OBJECTIVE: To elaborate cartilage tissue engineering in the gene transfer technology and its application, in addition, to make a prospects for its further application.METHODS: The database of Science Direct database (2003-01/2009-04) and CNKI (2003-01/2009-04) were retrieved with key words of "cartilage tissue engineering, gene transfer". The literature was limited to English and Chinese languages. Literatures concerning cartilage tissue engineering in the gene transfer technology were selected, including clinical research and basic research. Other unrelated papers were excluded. Chondrocyte differentiation and gene expression were observed.RESULTS: A total of 90 literatures were searched by computer, according to inclusive and exclusive criteria, the papers regarding cartilage tissue engineering in the gene transfection and gene types and options were analyzed. Gene transfer technology in the field of cartilage tissue engineering has broad application prospects. How to select genes associated with cartilage repair as the transfacted gene need urgent solution. Currently, the used target gene can be divided into following categories, including stimulated cartilage cell proliferation and differentiation, matrix formation, inhibit chondrocyta hypertrophy and osteoblast differentiation, anti-inflammatory response, inhibit senescence and inhibit apoptosis.CONCLUSION: It has a special significance to select the appropriate target genes, and to use a safe gene transfer method to repair cartilage. The clinical application of gene transfer technology is depended on the construction of safe and effective carriers,target genes, as well as transfection systems.

BACKGROUND: Adipose-derived mesenchymal stem cells have similar morphological and biological characteristics to bone marrow-derived mesenchymal stem cells, which can be used as sources of seed cells for tissue engineering.OBJECTIVE: To understand the biological characteristics of adipose-derived mesenchymal stem cells, and to explore its clinical application and prospects in tissue engineering field.METHODS: The databases of PubMed and CNKI were searched with key words of "adipose tissue-derived stem cell, tissue engineering, and stem cells". Literature search was limited to English and Chinese languages. The ossification potential of adipose-derived mesenchymal stern calls and the outcomes combined adipose-derived mesenchymal stem cells with gene transfection to treat diseases were served as evaluative indicators. The in vitro study of comparison between bone marrow-derived mesenchymal stem cells and adipose-derived mesenchymal stern cells in ossification was included, and irrelative or repetitive papers were excluded.RESULTS AND CONCLUSION: Adipose tissue-derived stem cells can be obtained in large numbers from adipose tissue, and stably proliferate and differentiated in vitro, which possess the similar characteristics to bone marrow-derived menchymal stem call in morphology and biology. Under certain induction, the adipose tissue-derived stem cells can directional differentiated into all three germ layers of cells. Combined adipose tissue-derived stem cells with tissue engineering scaffold could be used to repair bone and articular cartilage defects, but the quality and the surrounding cartilage connecting cartilage, bio-mechanical strength, and future normal cartilage degradation have a certain gap to normal cartilage. With the understanding of adult mesenchymal stem cell research, it found that the self-amplification and differentiation potential of mesenchymal stem cells can effective disused the import of "exogenous gene", thus, it is easy to in vitro genetic modification. Therefore, the adipose-derived stem calls can be combined with genetic engineering, and applied to gene therapy. However, in the present research, the remaining potential carcinogenicity in the gene vector and the negative impact after transfection has not been clarified.

Objective To investigate the expression of DNA methyltransferases (DNMTs) in liver cancer and its clinical significance. Methods The specimens of liver cancer tissues, adjacent tissues, cirrhotic tissues and chronic hepatitis tissues were collected from 50 patients who received radical resection at the First Affiliated Hospital of Sun Yat-Sen University from July 2007 to April 2008. The mRNA and protein expressions of DNMT1,DNMT3a and DNMT3b in liver cancer tissues, adjacent tissues, cirrhotic tissues and chronic hepatitis tissues were detected by real-time quantitative PCR and immunohistochemical staining. The mRNA expression of DNMTs in the liver cancer tissues was compared with those in the adjacent tissues, cirrhotic tissues and chronic hepatitis tissues by using t test and Mann-Whitney U test. The correlation between the protein expression of DNMTs in the liver cancer tissue and the clinicopathological features was analyzed by chi-square test or Fisher exact test, and the tumor-free survival time was analyzed by using Kaplan-Meier method and the difference in tumor-free survival rate between different patients was analyzed by Log-rank test. Results The mRNA expressions of DNMT1, DNMT3a and DNMT3b in the liver cancer tissue were 2.57, 2.29 and 4.86 times higher than those in the adjacent tissues (t = 3.94, 2. 72, 4. 06, P ＜ 0.05 ). The mRNA expressions of DNMT1, DNMT3a and DNMT3b were 2.38,2.14 and 4.66 times higher than those in the cirrhotic tissues, and 6.12, 4.58 and 12.99 times higher than those in the chronic hepatitis tissues. The mRNA expressions of DNMT1, DNMT3a and DNMT3b in the liver cancer tissue were significantly higher than those in the cirrhotic tissues and chronic hepatitis tissues ( U = 587.5,730. 0,562.5; 65.5, 64.5, 71.0, P ＜ 0.05). The protein expression of DNMT1 was correlated with the size, number,TNM stages and vascular invasion of tumors ( x2 = 4.08, 5.95, 4.08, P ＜ 0.05 ). The protein expression of DNMT3a was correlated with the size, number and TNM stages of tumors (x2 = 4.08, 5.95, 4.08, P ＜ 0.05 ).The mean tumor recurrence time of patients with low expressions of DNMT1 and DNMT3a were 9.4 and 8.7 months, which were significantly longer than 5.0 and 3.2 months of those with high expressions of DNMT1 and DNMT3a (x2 =3.89, 9.91, P＜0.05). Conclusions DNMTs play an important role in hepatocarcinogenesis.High expressions of DNMT1 and DNMT3a are correlated with the postoperative recurrence of liver cancer, which are valuable prognostic factors for liver cancer.

Objective To establish an animal model of PCOS and to detect the DNA methylation states of LHR, INSR and AR genes. Methods 24-days-old female Sprague-Dawley (SD) rats were randomly divided into two groups. The rats in the experimental group were given subcutaneous implanting of levonorgestrel silica gel staff and injected 1.5 IU hCG twice daily for 9 days from the 4th day. The rats in the control group were injected with normal saline at the same time. Ovarian morphologic changes, sex hormone levels, fasting serum insulin and glucose were detected. The LHR, INSR and AR genes' DNA methylation patterns were checked by methylation specific PCR in modeling group and control group. Results The ovarian weight and volume in modeling group were higher than those in control group. The ovaries in modeling group showed multiple follicular cysts, and the number of theca cells and interstitial cells increased. Less developed follicles and corpus lutea were seem. The serum level of progesterone, testosterone, luteinizing hormone, fasting insulin and glucose were significantly higher in experimental group than those in control group, so as the LH/FSH ratio and HOMA index. No methylation of LHR and AR genes were found in both groups. The methylation frequency of INSR gene (76.7%) was significantly higher in modeling group than that in control group (P<0. 001). Conclusion The depression of INSR gene's transcriptional induced by DNA methylation is important in the development of insulin resistance in PCOS.

Background and purpose: Gap junctions(GJ) could enhance cytotoxicity induced by chemotherapeutic agents. However, whether or not GJ composed of connexin 43 (Cx43) could increase etoposide cytotoxicity remains unclear. The aim of this study was to explore the effect of GJ composed of Cx43 on etoposide cytotoxicity in testicular cancer cells. Methods: Eighteen-glycyrrhetinic acid and siRNA were used to inhibit GJ function. Retinoid acid was used to enhance GJ function.“Parachute”dye-coupling assay was used to examine dye spread through GJ composed of Cx43 in MLTC-1 cells. “Standard colony-forming assay” was used to examine cell survivals of MLTC-1 cells treated with etoposide. Results: Assayed by “parachute” dye-coupling assay, the dye spread through GJ in MLTC-1 cells was significantly decreased by 18-glycyrrhetinic acid however increased by retinoid acid. Cx43 expression and GJ function in MLTC-1 cells were inhibited by Cx43-siRNA. Results from “standard colony-forming assay” showed that etoposide cytotoxicity was decreased by 18-glycyrrhetinic acid and siRNA, however enhanced by GJ function enhancer retinoid acid. Conclusion:The function inhibition of Cx43 composed GJ in MLTC-1 cells could decrease etoposide cytotoxicity. The enhancement of GJ composed of Cx43 in MLTC-1 could increase etoposide cytotoxicity.

Objective To establish an animal model of PCOS and to detect the DNA methylation states of LHR,INSR and AR genes. Methods 24-days-old female Sprague-Dawley (SD) rats were randomly divided into two groups. The rats in the experimental group were given subcutaneous implanting of levonorgestrel silica gel staff and injected 1.5 IU hCG twice daily for 9 days from the 4th day. The rats in the control group were injected with normal saline at the same time. Ovarian morphologic changes,sex hormone levels,fasting serum insulin and glucose were detected. The LHR,INSR and AR genes' DNA methylation patterns were checked by methylation specific PCR in modeling group and control group.Results The ovarian weight and volume in modeling group were higher than those in control group. The ovaries in modeling group showed multiple follicular cysts,and the number of theca cells and interstitial cells increased. Less developed follicles and corpus lutea were seem. The serum level of progesterone,testosterone,luteinizing hormone,fasting insulin and glucose were significantly higher in experimental group than those in control group,so as the LH/FSH ratio and HOMA index. No methylation of LHR and AR genes were found in both groups. The methylation frequency of INSR gene (76.7%) was significantly higher in modelinggroup than that in control group (P

Objective To investigate the best time of mini-traumatic operation to treat hypertensive intracerebral haemorrhage in internal capsule. Methods Sixty-four patients were divided into treatment group and control group according to operative time. Patients who were treated with mini-traumatic operation within 6 hours were as treatment group, those treated with mini-traumatic operation beyond 6 hours were as control group. Results Twelve of 40 patients in treatment group were cured, 16 became better, 5 had no effect, 7 were dead, and the effective rate was 70.00%. Five of 24 patients in control group were cured, 6 became better, 5 had no effect, 8 were dead, and the effective rate was 45.83%. Conclusion The effect of mini-traumatic operation to treat hypertensive intracerebral haemorrhage in internal capsule within 6 hours is clearly better than that beyond 6 hours.

This paper analyzes the special features of lemology education and the problems in clinical teaching at present,The measures should be taken to improve the clinical teaching quality from the varies of aspects,such as strengthening the construction of teaching staffs and students,applying the modern educational means and teaching samples in clinical teaching,launching active extracurricular activities,developing the evaluation of teaching and improving the teaching quality.

Objective To investigate the expression of DNA methyltransferases ( DNMTs) in hilar cholangiocarcinoma and its clinical significance.Methods A total of 150 samples of cholangetic tissues were collected from 111 patients with hilar cholangiocarcinoma ( cholangiocarcinoma group) and 39 patients with choledochocele ( control group) at the First Affiliated Hospital of Sun Yat-Sen University from April 1997 to March 2007.A tissue chip containing the samples of hilar cholangiocarcinoma and choledochocele was prepared.Expressions of DNMT1,DNMT3a and DNMT3b were detected by the immunohistochemical staining. Differences in the protein expressions of DNMTs in the cholangiocarcinoma group and the control group were compared,and the correlation between DNMTs protein expressions and clinicopathological features was analyzed.All data were analyzed by using the chi-square test or Fisher exact probability.The survival curve was drawn by using the Kaplan-Meier method and the survival rate was compared by using the Log-rank test.Results The rates of high protein expressions of DNMT1 and DNMT3b were 54.1％ (60/111) and 47.7％ (53/111) in the cholangiocarcinoma group, which were significantly higher than 28.2％ ( 11/39) and 23.1％ ( 9/39) in the control group　( x2 =7.740,7.240,P ＜0.05). The high protein expression of DNMT1 was correlated with-the Bismuth-Corlette classification and T staging of the tumor ( x2 =12.200, 17.800,P ＜0.05) ; there was no significant difference in the high protein expressions of DNMT3a in the cholangiocarcinoma group and the control group ( x2 =3.370.P ＞0.05 ) ; while the high protein expressions of DNMT3b was correlated with the Bismuth-Corlette classification (x2 =8.300,P ＜ 0.05 ),but not with the T staging. Sixty-six patients received hilar cholangiocarcinoma resection,and 42 of them were followed up.The median postoperative survival time of patients with low protein expression of DNMT1 was 23.9 months,which was significantly longer than 11.8 months of patients with high protein expression of DNMT1 (x2 =3.980,P ＜ 0.05).Conclusions DNMT1 and DNMT3b with high protein expression might play important roles in the carcinogenesis and development of hilar cholangiocarcinoma.There is an obvious relationship between the expression of DNMT1 and postoperative survival time of patients with hilar cholangiocarcinoma,and DNMT1 might be a valuable prognostic factor for hilar cholangiocarcinoma.

Objective To find out more optimal surgical approach for glioblastoma located in sensofimotor cortex and language area. Methods A respective review of 27 cases of glioblastomas located in sensorimotor and language area were operated, via the transsylvian-opercular approach, ineluding outcomes of microneurosurgery between January 2005 to December 2007. Results Among of 27 cases, tumors in 21 cases were covered by opereular cotex and were totally resected, tumors protruded into sylvian and wrapped around middle cerebral artery in 6 cases. 3 of them were totally removed, others were subtotally. Neurofunction of 26 cases were preserved of one were injuried. Conclusion Transsylvian-opercnlar approach for resection of glioblastomas located in subcortex of sensorimotor and language area is more optimal surgical approach, which not only ensure tumor resection with great degree, but preserve neurofunction well.