BACKGROUND:Destroying posterior stable structure of cervical vertebra may facilitate the ligamentum flavum regeneration. Whether anterior cervical instability can induce the regeneration in posterior and adjacent ligamentum flavum remains unclear.
OBJECTIVE:To observe the changes of transforming growth factor-β1 expression and histopathology in the ligamentum flavum of cervical instability animal models.
METHODS:Thirty-six New Zealand white rabbits were randomly divided into control group and experimental group, with 18 rabbits in each group. In the experimental group, cervical instability animal models were established made through destroying annulus fibrosus by anterior puncture and absorbing nucleus pulposus in C4/5 . And no intervention was given to the control group.
RESULTS AND CONCLUSION:Compared with the control group, fibers in the C 3/4, 4/5, 5/6 ligamentum flavum arranged disorderly and the glass like degeneration was found in the experimental group. The expression of transforming growth factor-β1 in ligamentum flavum was increased, especial y in C 4/5 , in the experimental group. At 4, 8, 12 weeks, transforming growth factor-β1 expression in the C 3/4, 4/5, 5/6 ligamentum flavum segments was similar between the two groups. Experimental findings indicate that, anterior cervical instability can induce the regeneration in posterior ligamentum flavum, especial y in the injured segment.

Objective To clarify the expression of leptin and leptin receptor in normal brain tissues and gliomas and investigate the effect of exogenous leptin on the proliferation,migration and invasion of human glioma U251 cell line.Methods Immunohistochemical staining was used to detect the expression of leptin and leptin receptor in 50 cases of different grades of glioma tissues and 20 cases of normal brain tissues.The effects of exogenous leptin on proliferation,migration and invasion of U251 cells were detected by MTT assay,cell scratch assay and Transwell invasion assay.Results (1) The positive expression rates of leptin and leptin receptors in glioma tissues were 50.0％ and 92.0％,respectively.(2)Proliferation activity:leptin concentrations of 0 ng/ml,10 ng/ml,and 50 ng/ml had no significant difference in the proliferation of U251 cells (absorbance:0.263±0.015,0.273±0.017 and 0.277±0.006,respectively),and the leptin concentration of 100 ng/ml had a significant effect on the proliferation of U251 cells (absorbance:0.315±0.005,P＜0.05).(3)Migration ability:the migration rate of U251 cells treated with different concentrations of leptin increased significantly with the passage of time,and the migration rate was most significant at the concentration of 100 ng/ml ((93.313±3.080) ％),and the difference was statistically significant (P＜0.05).(4)Invasive ability:with the increase of leptin concentration and the prolongation of the action time,the invasive ability of U251 cells was enhanced.When leptin was used at a concentration of 100 ng/ml,the number of penetrating cells were the biggest(135±2).Conclusion Leptin and leptin receptors are involved in the occurrence of gliomas;and exogenous leptin promotes the proliferation of U251 cells and has time and dose dependability on the migration and invasion of U251 cells.

Aim To construct a diabetic atherosclerosis mouse model and study the pathological characteristics of diabetic atherosclerosis.Methods Fifty 8-week-old male LDLR-/-mice were fed with standard diet for 2 weeks and then changed to high-fat diet,they were randomly divided into two groups.The diabetic atherosclerosis group was given intraperitoneal injection of low dose streptozotocin(STZ)for 5 days continuouly to establish the model,and the atheroscle-rosis group was given citrate buffer injection at the same time.The body mass,blood glucose and blood lipids of the mice in the two groups were detected for many times.At the age of 23 weeks,the mice were euthanized after glucose tolerance test.HE staining and oil red O staining were used to detect the gross and aortic root atherosclerosis,immunohistochemical staining was used to detect CD4,α-smooth muscle actin(α-SMA),EGF-like module-containing mucin-like hormone re-ceptor-like 1(EMR1),monocyte chemotactic protein-1(MCP-1),NOD-like receptor protein 3(NLRP3),vascular cell adhesion molecule-1(VCAM-1),matrix metalloproteinase-2(MMP-2)and tissue inhibitor of metalloproteinase-1(TIMP-1),Western blot was used to detect α-SMA,CD4,tumor necrosis factor-α(TNF-α),NLPR3,intercellular adhesion molecule-1(ICAM-1),and type Ⅰ and Ⅲ collagen.Results Compared with the atherosclerosis group,the body mass decreased,the levels of total cholesterol(TC),triglyceride(TG),low density lipoprotein cholesterol(LDLC)increased,and the levels of high density lipoprotein cholesterol(HDLC)decreased(P＜0.05)in the diabetic atherosclerosis group.Compared with the atherosclerosis group,the distribution of atherosclerotic plaques was diffuse and the area was increased in the diabetic atherosclerosis group,and the contents of lipids,T cells,macrophages,smooth muscle cells,type Ⅰ and Ⅲ colla-gen were increased(P＜0.05);the protein levels of TNF-α,MCP-1,MMP-2,NLRP3,ICAM-1 and VCAM-1 in vascular tissues were increased,while the content of TIMP-1 were decreased and MMP2/TIMP-1 were increased(P＜0.05).Conclusions LDLR-mouse model of diabetic atherosclerosis can be successfully established by STZ induction combined with high-fat diet,which can reflect the plaque composition and inflammatory characteristics of diabetes promoting atheroscle-rosis.It can be used as a relatively ideal pathological model for the study of diabetic macroangiopathy.

Objective: To understand the AIDS awareness and related factors as well as the demands for AIDS-related health education programs, among first-grade students from three senior high schools in Tianjin. Methods: A cross-sectional study using both stratified cluster and convenient sampling methods was conducted. Anonymous questionnaires including social demographic characteristics, AIDS-related knowledge and needs for AIDS health education were distributed to the first-grade students from two general middle schools and one vocational senior middle school in Tianjin. Results: A total of 1 082 students were responding to the questionnaires. Among them, the overall awareness rates of AIDS-related knowledge were 34.3%(371/1 082), 71.9%(778/1 082) of the students had received knowledge about AIDS and 59.4% (643/1 082) of the students had received knowledge about sexual health in the past, from the three schools. There appeared statistical differences among the two types of schools. 7.0% (76/1 082) of the students reported having had sexual behaviors. Results from the multivariate logistic regression analysis showed that, in vocational senior middle school, the awareness rate of AIDS knowledge was lower (compared with general middle school, OR=0.41, 95%CI: 0.29-0.59) and in the following items, including no need in receiving safe sex health knowledge (compared with needs of safe sex health knowledge, OR=0.62, 95%CI: 0.43-0.91), no interests in reading AIDS-related health education materials (compared with attention to AIDS health education materials, OR=0.41, 95%CI: 0.30-0.56), not aware of safe sex behavior (compared with aware of safe sex behavior, OR=0.55, 95%CI: 0.39-0.77), not aware of correct condom use, compared with aware of correct condom use (OR=0.33, 95%CI: 0.24-0.46). Conclusions The overall awareness rate of AIDS knowledge was low among the first-grade students in Tianjin. Some students reported of already having had insertive sex, sexual health knowledge has a significant impact on AIDS knowledge, suggesting that sexual health education and AIDS health education among high school students be strengthened in Tianjin.