Expression and significance of growth factor receptor binding protein 2 -associated binding protein -1 and glioma-associated oncogene homologue -1 in pediatric medulloblastoma / 中华实用儿科临床杂志

Objective To explore the expressions of growth factor receptor binding protein 2 -associated bin-ding protein -1 (Gab -1 )and glioma -associated oncogene homologue -1 (Gli -1 )in pediatric medulloblastoma,and to analyze their correlation between clinical and pathological characteristics and prognosis in pediatric medulloblastoma. Methods Elivision immunohistochemistry was used to detect the expressions of Gab -1 and Gli -1 protein in tissue microarray of 40 paraffin embedded pediatric medulloblastoma specimens.Chi -square test or Fisher exact test was used to analyze the correlation between Gab -1 and Gli -1 protein expressions with gender,age,tumor location and pathological subtypes.Follow -up data were handled by using Kaplan -Meier survival analysis and Cox regression anal-ysis.Results Positive expression ratios of Gab -1 and Gli -1 protein in 40 pediatric medulloblastoma were 35.0%and 55.0%,respectively.The positive expression rate of Gab -1 in medulloblastoma tissues had no statistical signifi-cance between different genders[male:30.4%(7 /23 cases)vs.female:41 .2%(7 /17 cases)],age[0.05).There were statistical differences of positive expression rate of Gli -1 protein in different age groups[0.05).Kaplan -Meier survival analysis showed that the age,the expressions of Gab -1 and Gli -1 protein were correlated with prognosis of pediatric medulloblastoma(all P <0.05).Cox regression indicated that the age,pathological subtypes and the expression of Gli -1 protein were independent prognostic indicators in pediatric medulloblastoma(all P <0.05).Conclusion Expression of Gab -1 and Gli -1 protein is significantly correlated with the prognosis of medulloblastoma,and the positive expression is a marker of unfavorable prognosis.

Expression of matrix metalloproteinases and tissue inhibitors of metalloproteinase in rats with cavernous transformation of portal vein and their role in peripheral angiogenesis / 中国组织工程研究

BACKGROUND:At present, there is no effective treatment strategy for cavernous transformation of portal vein and basic research about its etiology is rarely reported. OBJECTIVE:To establish the models of cavernous transformation of portal vein, detect the expression of matrix metal oproteinase-2,-9 (MMP-2, MMP-9) and tissue inhibitors 1, 2 of metal oproteinase (TIMP-1, TIMP-2) in rat portal vein and peripheral tissue, and discuss the roles in the process of peripheral angiogenesis. METHODS:Eighty Sprague-Dawley rats were randomly divided into three groups. The rat models of cavernous transformation of portal vein were established with partial coarctation in portal vein by using 21 G blunt pinhead. Control group was normal rats without operation (samples were harvested after portal vein radiography). Model group and sham operation group were divided into three groups respectively according to different time points, namely 2, 4 and 6 weeks after operation. Rats of each group were randomly chosen at week 2, 4 and 6 after operation to observe the formation of col ateral circulation of portal vein and its peripheral tissues by performing portal vein radiography. CD31 was detected by immunohistochemistry. The expression of MMP-2, MMP-9, TIMP-1, TIMP-2 mRNA and protein in portal vein and peripheral tissue were determined by RT-PCR and immunohistochemistry respectively. RESULTS AND CONCLUSION:Peripheral angiogenesis of model group was increased obviously by portal vein radiography and immunohistochemistry. RT-PCR and immunohistochemistry results demonstrated that, compared with the control group and sham operation group, the expression of MMP-2 mRNA and protein in model group were significantly increased at weeks 2, 4, and 6 (P0.05). Ratio of MMP-2/TIMP-2 of model group was significantly higher than that of control group and sham operation group (P<0.05) at week 2. the rat models of cavernous transformation of portal vein have low mortality, high success rate and are stable. Upregulation of the expression of MMP-2, MMP-9 and the disbanlance of the ratio of MMP-2/TIMP-2 might contribute to the peripheral angiogenesis in rats with cavernous transformation of portal vein.

Effect of vanillin inhalation on brain derived neurotrophic factor in depressed model rats / 中华行为医学与脑科学杂志

Objective To evaluate the relieving effects of vanillin sinffing on depression-like behaviors in depressed rats and to explore the possible underlying mechanism.Methods Depression animal model established by chronic unpredictable medium intensity stress combined with isolation and destroy the olfactory bulb.The depressed rats were divided randomly into vanillin inhalation group,fluoxetine hydrochloride group,depression model group,olfactory bulbectomy with the vanillin inhalation treatment group and sham-operated group.Nervous behavioral changes had been observed at different time after the administration of 5 weeks.The concentration of brain derived neurotrophic factor(BDNF) in the brain homogenate and the positive expression of BDNF in hippocampus had been also measured.Results Two weeks after the intervention,the immobility time of vanillin group((12.78 ±7.50) s) was lower than that of the model group((57.33±32.16) s) (P＜0.05).The consumption of saccharose in vanillin group((52.88±25.18)g) was higher than that of model group((37.40±19.33) g) (P＜0.05).BDNF of the brain homogenate in vanillin group (0.54±0.13) was significantly increased compared with model group (0.36± 0.06) (P＜0.01).When compared with the OBX group (0.40±0.06),similar result was obtained.Immunohistochemistry and the average density of image analysis revealed that the expression of BNDF of hippocampal CA3 in vanillin group (0.40±0.03)was significantly increased compared with model group (0.25±0.04) and OBX group (0.28±0.03) (P＜0.01).Conclusion Vanillin inhalation significantly relieves depression-like behaviors in depression rats.The possible mechanism may increase hippocampal neurogenesis by raising brain derived neurotrophic factor in brain.

Study on the differentiation of human mesenchymal stem cells into vascular endothelial-like cells / 生物医学工程学杂志

To explore the feasibility of mesenchymal stem cells (MSCs) acting as seed cells in tissue engineering, we isolated human bone marrow MSCs and differentiated them into vascular endothelial-like cells (ELCs) in vitro. Bone marrow mononuclear cells (BMSCs) were isolated by the method of percoll density centrifugation, and seeded in Dulbecco Modified Eagle Medium supplemented with 10% fetal bovine serum. MSCs were purified through multiple adherent cultures, and differentiated into ELCs induced by endothelial cell growth medium-2 (EBM-2) medium containing vascular endothelial growth factor (VEGF), human fibroblast growth factor (hFGF), insulin like growth factors 1 (IGF-1), and human epidermal growth factor (hEGF). The relative biologic characteristics of ELCs including cell morphology and phenotype were studied by inverted microscope and flow cytometry. The induced cells were identified by immunofluorescence with CD31 and Von Willebrand factor (vWF). The results showed that the morphology of MSCs was long-spindle and vortex-like growth. After induction of differentiation, the cells were round, and similar to vascular endothelial cells (ECs). Flow cytometric analysis revealed that ELCs expressed ECs specific surface markers of CD31 and vascular endothelial cadherin (VE-cadherin), but not CD133. Immunofluorescence results also confirmed that ELCs expressed CD31 and vWF. The results suggested that ELCs possed similar cell biological characteristics with ECs. In one word, human MSCs derived from bone marrow have the potential to differentiate into ECs in vitro, and show clinical feasibility acting as ideal donor cells of vascular tissue engineering.

Reforming the practice teaching of human anatomy / 中华医学教育探索杂志

Objective To explore the practice teaching model of human anatomy through re-forming the practice teaching of system anatomy and regional anatomy. Methods Three classes of clinical medicine (5-year program) were randomly selected as reform experimental classes and the other 3 classes of the same grade were used as control classes. The teaching content of practice teach-ing was reformed in the experimental classes. In the system anatomy practice teaching, the teacher controlled the teaching process and developed the theme and requirements of each experimental class while the student completed the experiment developed by the teacher. In the regional anatomy practice teaching, students' interest in learning was stimulated by the content , which was related with the surgery, and the teacher guided students to complete the operation. In control classes, the forms of student observation as well as teacher answering questions and helping students were adopted. The student grading was divided into theoretical knowledge examination and specimen assessment and the achievement was analyzed by using a Simple Analysis of Variance (ANOVA) in SPSS 16.0. Results Compared with those of control classes, the scores of system anatomy and regional anatomy in experi-mental classes were significantly increased (80.7±5.8) vs. (67.4±17.4), (85.1±4.6) vs. (62.6± 12.4) and the theoretical scores of system anatomy were also improved significantly. But no significant difference in theoretical scores of regional anatomy was observed. Conclusions The teaching mode based on the practice teaching highlights the academic characteristics of the human anatomy, increas-es students' interest in learning and improves the effectiveness of practice teaching in human anatomy.

Three-dimensional finite element model of mandibular complete overdenture and its biomechanical characteristics / 中国组织工程研究

This study aimed to construct throe-dimensional finite element model of the mandibular complete overdenturo and to analyze the influence rules for stress distribution under different mandibular shapes. The layer cutting method was employed as a basic tool to deal with different plaster models to gain two-dimensional point data. These data were introduced to the commercial software ANSYS to construct throe-dimensional finite element model of the mandibular complete overdenturo, including nine kinds of typical shapes, such as sharpness, roundness and squareness, and etc. Static loads were imposed on denture so as to accomplish biomechanicel analysis and to study the influence rules of stress distribution for mandibular complete overdenturo under different mandibular shapes. Results revealed that the sequence of stress from high to low was squareness, roundness, sharpness and the other extrapolated, basic and inside. The throe-dimensional finite element model has high simulation accuracy and the results provide an experimental foundation and guidance for clinical work.