BACKGROUND:Bone marrow mesenchymal stem cel s are likely to repair renal injury by differentiating into renal parenchymal cel s. OBJECTIVE:To explore the effect and mechanism of bone marrow mesenchymal stem cel s in the renal repair after mesangial proliferative glomerulonephritis. METHODS:Thirty Sprague-Dawley rats were randomized into normal group, model group and treatment group (n=10 per group). Model group and treatment group were treated with tail vein injection of mouse anti-rat monoclonal antibody Thy1.1 to prepare mesangial proliferative glomerulonephritis models. One week after modeling, rats in the treatment group were given 2×106 bone marrow mesenchymal stem cel s via the tail vein, and rats in the other two groups were given the same volume of normal saline. Two weeks after transplantation, urinary protein, urea nitrogen, creatinine levels were detected;hematoxylin-eosin staining was used for observing pathological changes of the renal tissue under microscope;and the expression of transforming growth factor beta 1 was detected by immunohistochemistry method. RESULTS AND CONCLUSION:The levels of urinary protein, urea nitrogen and creatinine as wel as the expression of transforming growth factor beta 1 in the renal tissue arranged in descending order were listed as fol ows:model group>treatment group>control group, and there were significant differences among three groups (P<0.05). In the model group, diffuse glomerular hyperplasia was observed with the presence of increased extracel ular matrix, partial glomerular sclerosis, and interstitial infiltration of inflammatory cel s;in the treatment group, glomerular hyperplasia, mesangial proliferation and inflammatory cel infiltration were al mitigated compared with the model group. Therefore, bone marrow mesenchymal stem cel transplantation may contribute to renal repair after mesangial proliferative glomerulonephritis, by inhibiting overexpression of transforming growth factor beta 1 in the kidney.

Objective To evaluate 3D printing abdominal aortic aneurysm model in analysis of clinical teaching effect for standardized resident doctors in vascular surgery department. Methods 48 resi-dents in vascular surgery department in our hospital from December 2016 to September 2017 were seleeected and randomly divided into control group and the experimental group. The traditional vascular surgical anatomy atlas, ultrasound, CT abdominal blood vessel 3D reconstruction, digital subtraction, video and so on were used by 24 residents in the control group, while in the experimental group, on the basis of the traditional teaching, abdominal aortic aneurysm model of 3D printing, true aortic coated stent delivery system were increased. After the teaching, the theory of evaluation (abdominal vascular anatomical features, morphological characteristics and classification of AAA, measurement of various parameters and key points of operation in the EVAR) and satisfaction questionnaire were adopted to evaluate the effect of two kinds of teaching methods. SPSS 19.0 was used to conduct t test on two groups of physician evaluation data. Results The results of theoretical assessment showed that there was no significant difference between the control group and the experimental group in the abdominal vascular anatomical features, the morphological features and the classification of the experimental group (P>0.05) in the examination of the common AAA cases and the complicated AAA cases. However, the experimental group was higher than the control group in the mea-surement of the parameters of EVAR, and the score of the operation points and the total score, and the difference was statistically significant (t=2.283, t=2.263, P<0.05). The results of the questionnaire showed that the students' satisfaction scores on the teaching satisfaction of the normal and complex AAA cases were better than those of the control group, and the difference was statistically significant (P<0.05). Conclusion The 3D printing model can increase the understanding and mastery of the anatomy and treat-ment of abdominal aortic aneurysm and improve its learning enthusiasm for vascular surgery. We should make full use of the advantages of 3D printing technology on the basis of retaining the advantages of tradi-tional teaching methods and means, and further enhance the teaching effect.