1. Effects of immunosuppression on post-injury regeneration of peripheral nerve in rats
Academic Journal of Second Military Medical University 2006;27(9):941-945
Objective: To investigate the effects of immunosuppression treatment on peripheral nerve injury and regeneration in rats. Methods: Forty-nine SD rats were randomly divided into 7 groups: sciatic nerve (in the middle of left thigh) forceps-crushing+cyclophosphane, transecting+cyclophosphane, resecting groups+cyclophosphane, forceps-crushing+normal saline, transecting+normal saline, resecting groups+normal saline, and blank control groups. Cyclophosphane and normal saline were intraperitoneally injected into rats post-operatively. Peripheral nerve regeneration and its related function were assessed by walking track analysis, electrophysiology and histomorphology; immunohistochemistry method was used to evaluate the local autoimmune reactions 12 weeks after operation. Results: Cyclophosphane treated animals had higher scores of sciatic function index (SFI) compared to animals in the corresponding normal saline groups. The electrophysiological (nerve conduction velocity) and morphological examinations showed better regeneration of the myelinated axons in immunosuppression-treated animals compared to the corresponding normal saline groups. The immunohistochemistry showed that the intensities of the local immunological response in immunosuppression groups were obviously lower as compared to the corresponding normal saline groups. Conclusion: There is local autoimmune reaction in post-traumatic nerve regeneration and this autoimmune reaction may influence nerve regeneration. Cyclophosphane treatment can suppress this autoimmune reaction and improve the micro-environment for nerve regeneration.
2.Caveolin-1 expression is downregulated by shear stress and TNF-? in human aortic endothelial cells
Qing XIANG ; Xi DONG ; Mei XU ; Ruijuan SUN
Chinese Journal of Pathophysiology 1989;0(05):-
AIM: To observe effects of shear stress and TNF-? on caveolin-1 expression. METHODS: Cultured human aortic endothelial cells (HAECs) of passage 3-5 were used in the experiment. Cells were exposed to a laminar flow (shear stress 1.0 Pa) by using a parallel rectangular flow chamber for different time. Caveolin-1 mRNA and protein expression were measured by RT-PCR and Western blot, respectively. Caveolin-1 expression of the cells stimulated by TNF-? were also studied to elucidate the influence of this inflammatory factor. RESULTS: After 24 h of exposure to 1.0 Pa shear stress, both of caveolin-1 protein and mRNA expression decreased in HAECs, especially caveolin-1 mRNA expression (P
3.Expression of MMP-1, MMP-3 and iNOS in cartilage of experimental rabbit osteoarthritis induced by anterior cruciate ligament transection
Shu-Qian HE ; Hai-Bin WANG ; Qing SUN ; Dong-Mei ZHAO ; Shi-Qing LIU ; Bo QIU ;
Chinese Journal of Rheumatology 2001;0(05):-
Objective To observe the expression of matrix metalloproteinases(MMP)-1,MMP-3 and iNOS in cartilage of experimental rabbit osteoarthritis at different time intervals after anterior cruciate ligament transection(ACLT)operation.The aim of this study is to provide the theoritical evidence for using ACLT rabbit model in Osteoarthritis(OA)research.Methods Unilateral ACLT was performed on 27 randomly selected while rabbits and underwent unilateral arthrotomy was performed on the other 9 white rabbits as the control group.Nine randomly selected white rabbits in experimental group were killed and 3 white rabbits in the control group at 4th,8th and 12th week respectively.Cartilage degradation of femoral condyles was evaluated macr-oscopically,mRNA expression level and protein expression level of MMP-1,MMP-3 and iNOS was measured by reverse transcription-polymerase chain reaction(RT-PCR)and immunohistochemistry respectively.Results Forepart OA cartilage degradation was observed at the 4th week and became more severe at the 8th week after ACLF.Afterpart cartilage degradation was evident at the 12th week after ACLT while cartilage still remained normal in the control group,mRNA expression level and protein expression level of MMP-1.MMP-3 and iNOS were increased at the 4th week and became higher gradually at the 8th,12th week after ACLT compared with the control group.Expression distribution of MMP-1,MMP-3 and iNOS bad different patterns respectively.Conclusion It is suggested that the process of OA cartilage degradation can be simulated by ACLT model and MMP-1,MMP-3 and iNOS may be good markers in therapeutical research of OA.
4.Effect of Fusion Protein Cleavage Site Mutations of NDV ZJ1 Strain on Its Fusion Activity
Yan-Mei ZHANG ; Shun-Lin HU ; Qing SUN ; Yan-Tao WU ; Xiu-Fan LIU ;
Microbiology 1992;0(04):-
NDV strain ZJ1 strain , a highly virulent NDV strain, has been prevalent among the waterfowls in China mainland in the past years. Multi-basic amino acid sequence distribute in the protease cleavage site of F protein of this strain. Recombinant expressing plasmid pCI-FT, was generated by converting multi-basic amino acid sequence of 112, 115, 117 of the protease cleavage site of F_ 0 protein, to the non-basic amino acid sequence characteristic of avirulent NDV strain. The result from co-expression of mutant or parental F protein with homologous HN protein in COS-1 cells revealed that both mutant and parental F protein had fusion activity. The result from co-expression of mutant or parental F protein with homologous HN protein in CEF cells showed that the cleavage activity of mutant F protein was significantly reduced. The study built a foundation for mutagenesis of amino acid sequence of the protease cleavage site of F_ 0 protein at the full-length cDNA clone level, study on factors contributing to virulence and construction of candidate vaccine strain, and so on.
5.Cyclic tensile stress affects the expression of matrix metalloproteinases in chondrocytes
Xingmo LIU ; Qing SUN ; Yucheng XIANG ; Xinjun MEI ; Sheng HUANG ; Tao PAN
Chinese Journal of Tissue Engineering Research 2013;(28):5157-5163
BACKGROUND: Previous studies have confirmed that in the animal models of articular cartilage defects and osteoarthritis, the chondrocytes can overexpress the matrix metal oproteinases. Various abnormal stimuli are likely to break the balance between matrix metal oproteinase and tissue inhibitor of metal oproteinase, thus leading to degeneration of extracel ular matrix of articular cartilage, as wel as the decline and offset of cartilage chondrocytes. OBJECTIVE: To observe the effect of cyclic tensile strain on the expression of matrix metal oproteinases during the repairing process of rabbit articular cartilage defects. METHODS: The animal models of articular cartilage defects were established, and chondrocytes were separated for culture at 10 weeks after operation. The chondrocytes on the non-surgical side were considered as the normal group, and the chondrocytes on the surgical side were randomly divided into high cyclic tensile strain group, low cyclic tensile strains group and control group, and the load amplitude was sin10%. Then 0.1, 1.0 and 0 Hz cyclic tensile strains were loaded respectively. The expressions of matrix metal oproteinases 2, 3, 9 and 13 in each group were detected with reverse transcription-PCR at 24, 48 hours, 1, 2 and 4 weeks after loading cyclic tensile strain. RESULTS AND CONCLUSION: There were significant differences in the expressions of matrix metal oproteinases 2, 3, 9 and 13 at 24 hours after loading cyclic tensile strain between the normal group and the control group (P < 0.05); and there were significant differences in the expressions between the high cyclic tensile strain group and the low cyclic tensile strain group at 1, 2 and 4 weeks after loading cyclic tensile strain (P < 0.05).At the same time, the expressions of matrix metal oproteinases 2, 3, 9 and 13 in the low cyclic tensile strain group were continued to decline, and there were significant differences in the expressions after loading cyclic tensile strain for 24 hours and 4 weeks (P < 0.05). The results indicate that mechanical load can affect the expression of matrix metal oproteinases in the healing process of rabbit articular cartilage defects. In the cel ular and molecular level, the incidence and development of pathological articular cartilage defect and stress should affect each other.
6.Anti-tumor effects of a novel cyclophosphamide derivate 9b in vivo and in vitro.
Pu-Mei CUI ; Li SHU ; Fei LIU ; Jun-Qing YANG ; Yang SONG ; Wen-Juan SUN
Acta Pharmaceutica Sinica 2014;49(1):44-49
This study is to investigate the anti-tumor activities of a novel cyclophosphamide derivate 4, 6-diphenyl cyclophosphamide (9b) in vivo and in vitro, and its possible mechanism of action. The inhibitory effects of 9b on human hepatoma cell line HepG2, human breast carcinoma cell line MCF-7 and human myeloid leukemia cell line K562 were measured by MTT assay in vitro. Cell cycle distribution and apoptotic rate were evaluated by flow cytometry. To evaluate the anti-tumor effect of 9b in vivo, mouse model bearing inoculated H22 tumor was established. The results indicated that 9b could inhibit the proliferation of HepG2, MCF-7 and K562 cells in a dose and time dependent manner. The ICo50 values of 9b were 32.34 micromol.L-1 to HepG2 cells, 87.07 micromol.L-1 to MCF-7 cells and 149.10 micromol.L-1 to K562 cells after incubation for 48 h. The results of flow cytometry indicated that after being treated for 48 h with different concentrations of 9b, the ratios of HepG2, MCF-7 cells at the Go/G1 phase and K562 cells at the G0/Gl phase and G2/M phase increased significantly compared with control group, and the apoptotic rate increased with the increase of the concentration of 9b. 9b could significantly reduce tumor weight of H22 solid tumor mouse model in vivo. To summarize, 9b showed significantly anti-tumor activity in vivo and in vitro, of which the mechanism might be associated with the change of cell cycle distribution and induction of tumor cell apoptosis.
Animals
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Antineoplastic Agents, Alkylating
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chemistry
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pharmacology
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Apoptosis
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drug effects
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Cell Cycle
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drug effects
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Cell Line, Tumor
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Cell Proliferation
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drug effects
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Cyclophosphamide
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analogs & derivatives
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chemistry
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pharmacology
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Dose-Response Relationship, Drug
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Female
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Humans
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Inhibitory Concentration 50
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Liver Neoplasms, Experimental
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pathology
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Male
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Mice
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Molecular Structure
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Random Allocation
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Tumor Burden
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drug effects
8.Potassium channel gene expression in myocardial sleeves of pulmonary vein and effects of amiodarone on rabbits with rapid atrial pacing
Jiangrong WANG ; Yinglong HOU ; Liaosheng ZHOU ; Mei GAO ; Changwen SHI ; Qing WANG ; Yingying SUN ; Wei LIU
Chinese Journal of Pathophysiology 2000;0(08):-
AIM: To investigate the potassium channel gene expression of myocardial sleeves of pulmonary vein and effects of amiodarone on rabbits with rapid atrial pacing.METHODS: Rabbits were divided into three groups(n=10),(1) the control group with sham operation and placebo;(2) the right atrial pacing(RAP) group at 600 beats/min with the placebo;(3) the amiodarone group treated for seven days with oral amiodarone at 100 mg ? kg-1 ? d-1.Based on RAP simultaneously,the messenger ribonucleic acid(mRNA) of specimen was measured by reverse transcription-polymerase chain reaction.RESULTS: Compared with the control group,Kv4.3(transient outward K+ current,Ito1) mRNA expression in RAP group was reduced by 51%(P
9.The construction and identification of Fas-targeting siRNA-expressing plasmid
Suhu LIU ; Wanggang ZHANG ; Mei ZHANG ; Qing ZHU ; Wei TIAN ; Jingxi SUN
Journal of Xi'an Jiaotong University(Medical Sciences) 1981;0(02):-
Objective To construct Fas-targeting siRNA-expressing plasmid, and explore the significance of Fas inhibition in the treatment of acute aplastic anemia. Methods U6 promoter cassette and siFas sequence were obtained by PCR method, and cloned into modified pcDNA3.1 to produce plasmid pU6-siFas, which was transfected into P815 cells with limpofectin 2000, and then Fas expression was detected by immunohistochemistry. Results The plasmid pU6-siFas could efficiently reduce the expression of Fas and confer G-418 resistance in P815 cells. Conclusion The successful construction of the siRNA expressing plasmid will facilitate the application of RNA interference technique, and lay foundation for further studies of the therapeutic effect of Fas inhibition on acute aplastic anemia.
10.Study on the current status and influential factors of neglect of left-behind children in rural area of Anhui province
Chao-Mei GU ; Ye-Huan SUN ; Lin-Sheng YANG ; Teng-Wei HAN ; Tie-Zhu WANG ; Ying SUN ; Qing-Qing CAO
Chinese Journal of Epidemiology 2011;32(12):1212-1215
Objective To understand the status and influential factors of those neglect of left-behind children in rural area,and to provide bases for the development of intervention measures.Methods 2917 students were selected as the study subjects from Changfeng county of Anhui province with cluster sampling method and were evaluated by a Parents-Child Conflict Tactics Scales and questionnaire on influential factors.Results 1694 left-behind children,accounted for 58.1% of the total students,were surveyed in this investigation.The prevalence rates of neglect,among total children,left-behind children,non-left-behind children were 67.4%,70.2%,63.5%,respectively.The prevalence of neglect among left-behind children was higher than that among non-left-behind children (x2=14.322,P<0.000).There were no significant associations with the neglect rate of left-behind children regarding gender or age differences.Result from multivariate logistic regression analysis indicated that the neglect among the left-behind children were associated with family dysfunction(OR values of moderate and serious family dysfunctions compared to good family function were 1.628 and 2.341,respectively)and the rate of keeping in touch with parents(OR values of sometimes and seldom keeping in touch compared to regular in touch were 1.299 and 1.844,respectively).The starting age of being left-behind(OR values of starting age that being left-behind from 6 to 10 and ≤5 years relative to starting age of left-behind ≥11 years were 0.703 and 0.630,respectively)appeared to be the protection factor to the neglect of those left-behind children.Conclusion Our findings indicated that the status of neglect among the left-behind children was serious.Prevention programs on the issue should target on a number of factors,including the characteristics of the chldren them-selves,as well as on the family of the children.