BACKGROUND:As an important cytokine, interleukin-6 regulates immune responses in inflammation sites and has an autocrine/paracrine activity that stimulates osteoclast formation and bone resorption, which is related to bone remodeling during orthodontic tooth movement.
OBJECTIVE:To investigate the effects of orthodontic force on the expression of interleukin-6 mRNA in the periodontal tissue of rats.
METHODS:In situ hybridization was performed to measure the expression of interleukin-6 mRNA at 1, 3, 5, 7, 10 and 14 days after the application of orthodontic force on the maxil ary first molars of rats.
RESULTS AND CONCLUSION:The expression of interleukin-6 mRNA was observed at a low level in the normal periodontal tissue of rats. After the application of force, the induction of interleukin-6 mRNA was observed to reach a maximum on day 3 and to decline thereafter. The expression of interleukin-6 mRNA can be evoked by orthodontic force but with a certain self-limiting. As a multifunctional cytokine, interleukin-6 plays a very important role in periodontal remodeling during orthodontic tooth movement.

Objective To evaluate the effect of hyperoxygenated solution on myocardial injury in the rats with acute carbon monoxide (CO) poisoning.Methods Thirty pathogen-free adult male SpragueDawley rats,weighing 250-300 g,were randomly divided into 5 groups (n=6 each) using a random number table:control group (C group),acute CO poisoning group (ACP group),and different doses of hyperoxygenated solution groups (HP1-3 groups).CO 120 ml/kg was injected intraperitoneally to establish the model of acute CO poisoning.Hyperoxygenated solution 10,15 and 20 ml/kg were infused via the caudal vein at 1 h after intraperitoneal injection of CO in HP1-3 groups,respectively.At 24 h after intraperitoneal injection of CO,blood samples were collected from the caudal vein for determination of plasma creatine kinase (CK),creatine kinase-MB (CK-MB),lactic dehydrogenase (LDH) and alpha-hydroxybutyrate acid dehydrogenase (α-HBDH) activities using the automatic biochemical analyzer.The rats were then sacrificed,and myocardial specimens were obtained for examination of the pathological changes with a light microscope.Results Compared with group C,the plasma LDH,α-HBDH,CK and CK-MB activities were significantly increased in ACP and HP1-3 groups (P＜0.01).Compared with group ACP,the plasma LDH,α-HBDH,CK and CK-MB activities were significantly decreased in HP1-3 groups (P＜0.05 or 0.01).Compared with group HP1,the plasma LDH,α-HBDH,CK and CK-MB activities were significantly decreased in HP2,3 groups (P＜0.05).The pathological changes of myocardium were significantly attenuated in HP1-3 groups as compared with group ACP.Conclusion Hyperoxygenated solution can attenuate myocardial injury in the rats with acute CO poisoning.

to observe the infarction volume.Nitrate reductase assay was used to detect the level of NO in brain tissue of the rats.The level of S100βin brain was detected by ELISA method.Results Compared with model group,the brain infarction volumes of the rats 24 and 72 h after cerebral ischemia reperfusion in curcumin group were significantly decreased (P<0.05).Compared with sham operation group,the NO and S100βlevels in the brain tissue 24 and 72 h after cerebral ischemia reperfusion of the rats in model group were significantly increased(P<0.05);compared with model group,the levels of NO in the brain tissue 24 and 72 h after cerebral ischemia reperfusion in curcumin group were remarkably decreased (P<0.05);compared with modee group,the level of S100βin the brain tissue 72 h after cerebral iscemia reperfusion in curcumin group was remarkably decreased (P < 0.05 ). Conclusion Curcumin can significantly reduce the degree of ischemia reperfusion injury in the rats and reduce the levels of NO and S100βin brain tissue,which suggests that the decrease of NO and S100βlevels in brain tissue may be associated with the neuroprotective effect of curcumin.