1.Regulation of MMP-2 and TIMP-3 expression by uPA signal transduction system in human bone giant cell tumor
Ruobing XU ; Jianming WEN ; Meng ZHANG ; Changhai L ; Gang XIAO ; Wenmin ZHANG ; Huizhen LIANG
Chinese Journal of Pathophysiology 2000;0(11):-
AIM: To study effects of urokinase-type plasminogen activator (uPA) signal transduction on expression of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) in giant cell tumor of bone (GCT). METHODS: Expression of uPAR, MMP-2 and TIMP-3 in GCT tissue was detected by immunohistochemistry. Phosphorylation level of mitogen-activated protein kinase (p44) in uPA/uPAR signal pathway in cultured GCT cells was detected by immunoprecipitation. The expression of MMP-2 and TIMP-3 in cultured cells after treatment with uPA-ATF or anti-uPAR antibody was also detected by Western blotting. RESULTS: 1) Urokinase-type plasminogen activator receptor (uPAR) was positive on the cell membrane and in cytoplasm of some mononuclear stromal cells (MSCs) and multinucleated giant cells (MGCs); 2) MMP-2 was positive in the cytoplasm and on the cell membrane of almost all of MSCs and some of MGCs. The polar distribution of MMP-2 in the cytoplasm of MGCs was especially obvious; 3) The expression of TIMP-3 of some MSCs and MGCs in GCT was much lower than MMP-2. The positive signal also showed a prominent polarity; 4) After treatment with uPA-ATF, the phosphorylation level of p44 in GCT cultured cells was much higher than the control. Addition of anti-uPAR antibody in the cells remarkably down-regulated the phosphorylation level of p44 as compared with the control group, suggesting that uPA-ATF participates cell signal transduction and this reaction can be inhibited by anti-uPAR antibody; 5) uPA-ATF cell signal pathway up-regulated expression of MMP-2 and TIMP-3, while anti-uPAR antibody down-regulated the expression of MMP-2 and TIMP-3. CONCLUSION: These results demonstrate for the first time that uPA-ATF directly regulates the expression of MMP-2 and TIMP-3 by signal transduction pathway, and the over-expression of MMP-2 and TIMP-3 may play an important role in local osteolysis of GCT. [
2.Characterization of urocortin in human pregnancy
Qing GU ; Jinyan SHA ; L VICKI ; Schwartz JEFFERY ; Madsen GEMMA ; Smith ROGER ; J SCHWARTZ
Chinese Medical Journal 2001;114(6):618-622
Objective To examine whether urocortin is produced locally to regulate utero-placental vascular tone during pregnancy. Methods We examined the distribution of urocortin in human placenta, fetal membranes and uterine tissue at term in the presence and absence of labor using a urocortin antibody produced in our laboratory and the immunoperoxidase staining method. Subsequently, we tested urocortin secretion from chorio-decidual cells in vitro using an immunoblot technique. Then, we tested whether urocortin is present in maternal plasma throughout gestation using a radioimmunoassay. A Sephadex G-50 column was used to examine whether immunoreactive urocortin (IR-urocortin) in maternal plasma is the same as synthetic urocortin. Results IR-urocortin was observed in vascular smooth muscle of myometrium decidual stromal cells, syncytiotrophoblast and amnion epithelium. No differences in staining intensity for urocortin were detected between tissues obtained in the absence or presence of labor. Staining intensity for IR-urocortin was greatest in the decidua, suggesting this may be the main site of urocortin production. Positive staining for urocortin was observed in 40% of chorio-decidual cells with 34% of these cells secreting urocortin under basal conditions. Urocortin was detectable in maternal plasma from 16 weeks gestation and concentrations did not change as gestation progressed. IR-urocortin in the maternal plasma eluted from a Sephadex G-50 column at the same site as synthetic urocortin and had a calculated retention co-efficient of 0.44. Conclusion This study indicates that urocortin is produced by the decidua during human pregnancy and is detectable in maternal plasma. These data are consistent with the hypothesis that urocortin is produced locally by the decidua and may act to regulate utero-placental blood flow.
3.Pediatric burns due to hot water from water dispenser: a neglected issue that should be highly concerned
Bing MA ; Hui-Jun XI ; Jia-Lin WANG ; Ying YAN ; Hong-Tai TANG ; Shi-Hui ZHU ; Kai-Yang L(U) ; Zhao-Fan XIA
Chinese Medical Journal 2012;(11):2053-2056
Background More and more Chinese drink hot water from water dispensers while many children were scalded due to this change.The present study aimed to propose a feasible strategy for prevention.Methods A retrospective study was conducted for all water dispensers related pediatric burns admitted to Changhai Hospital from January 2005 to December 2009.Results The number of new cases and incidences of pediatric burns due to hot water from water dispensers was significantly increasing year after year.In the total 238 involved cases,175 cases happened on males and 78.9% were at the age of 1-4 years.The burn areas were mainly located in upper extremities.All water dispensers in the surveyed families had no isolate protection devices and 85.2% of their locations were easy for children to reach.Nearly half of the children were in the same room with their guardians when injured.Total 196 burned children were playing the taps of water dispensers before injured,unfortunately,80.6% of them have not been stopped until burned.Conclusion As the kind of bums is quite serious and with bad outcome,some recommendations should be followed,such as buying water dispensers with protection devices,keeping children from touching them and so on.