BACKGROUND: One of the basic functions of bone is its adaptation to mechanical loading environment. Bone cells are the mechanosensitive cells in bone tissue. However, the mechanisms by which mechanical signals are transduced to chemical signals that influence bone growth and metabolism remain unidentified.OBJECTIVE: To understand the mechanotransduction pathways in osteoblasts and osteocytes, and to provide a theoretical basis for further study. METHODS: PubMed database was retrieved by computer with key words of osteoblast, osteocyte, bone cells, mechanical stress. According to inclusion criteria, 69 articles were included to summarize the transduction of mechanical signals of bone cells. RESULTS AND CONCLUSION: One of the basic functions of bone is its adaptation to mechanical loading environment. Bone cells are mechanosensitive cells. However, how the transduction of mechanical signals of cells realizes and how regulates skeleton remain poorly understood. Studies confirmed that due to the construction features and cell location of skeleton, osteoblasts and osteocytes are the most important mechanosensitive cells in bone tissue. The process of mechanotransduction can be divided into four distinct steps: ① mechanocoupling; ② biochemical coupling; ③ signal transmission; ④ effector response of bone cells. Through these four steps, the loads acting on the bones are transduced into biochemical signals, and then change the function of bone cells, finally induce the changes of bone structures to adapt the mechanical environment. The regulatory mechanisms of mechanical signals in bone marrow mesenchymal stem cells require further investigation.

Animals ; Antioxidants ; therapeutic use ; Coronary Disease ; drug therapy ; Drugs, Chinese Herbal ; therapeutic use ; Free Radical Scavengers ; therapeutic use ; Humans ; Pancreatitis ; drug therapy ; Phytotherapy ; Salvia miltiorrhiza ; chemistry

Ginseng is a typical adaptogen which has resistance to various stresses. This effect is related to the hypothalamic-pituitary-adrenal (HPA) axis. As the main active ingredients, saponin has the similar structure to steroids. The regulation characteristics of ginseng saponin on the HPA axis are narrated from the aspects of total saponin and saponin monomers in this paper after the introduction of adaptation definition and HPA axis regulation mechanisms. Pharmacological effects of ginseng saponin and the regulation effect of HPA axis are summarized finally.
Adaptation, Physiological ; Adrenocorticotropic Hormone ; secretion ; Animals ; Corticosterone ; secretion ; Ginsenosides ; isolation & purification ; pharmacology ; Humans ; Hypothalamo-Hypophyseal System ; drug effects ; secretion ; Panax ; chemistry ; Pituitary-Adrenal System ; drug effects ; secretion

Osteoblasts are the most important mechanoreceptive and osteogenic cells.The loss of bone in microgravity is mainly due to the dysfunction of osteoblasts.Research on osteoblast cytology under simulated weightlessness has made great progress in recent years.Current experiments are focusing on the changes in the cellular proliferation,differentiation,apoptosis, function and signal transduction in osteoblasts.This paper reviews the progress of the studies in this field.

Objective: To investigate the effect of paeonol (Pae) on the proliferation of human ovarian cancer cell line A2780s in vitro. Methods: Inhibitory effects of Pae with different concentrations on A2780s cells were detected by MTT assay. The cell cycle distribution and the apoptosis rate of A2780s cells were determined by flow cytometry (FCM). Results: The proliferation of A2780s cells was significantly inhibited after treatment with Pae (7.81-250.00 mg/L) in a concentration- and time-dependent manner. FCM results showed that the proportion of cells in S phase was increased while which in G0/G1 phase and G2/M phase were decreased after treatment with Pae (31.25-250.00 mg/L) for 48 h. The apoptosis rate of A2780s cells induced by Pae was increased in a concentration-dependent manner. Conclusion: Pae can inhibit the proliferation and induce the apoptosis of human ovarian cancer cells.

Objective To better understand and manage the current situation and problems of patent transformation in university affiliated hospital.Methods we conducted the statistical analysis the quantity of patent authorization in the Peking University People's Hospital during 2002-2013,and the status of patent transformation.Results The quantity of patent authorization increased significantly,however the number of patent transformation is small,with low proportion.Meantime,the transformation period is long,with single mode.Conclusions the hospital should be strengthened for all patent life-cycle management,and strengthen the emphasis on the conversion work to build integrated management team,in particular by building technological achievements promotion platform,improve the incentive mechanism to strengthen the franchise use of the work.

OBJECTIVE:To improve the determination method for lincomycin hydrochloride eye drops so as to eliminate the interference of the bacterial inhibitor ethylparaben on the content of the main component.METHODS:The determination was performed by HPLC with phosphoric buffer (pH 6.8)-methanol (40∶ 60) as the mobile phase replacing the mobile phase of borax buffer (pH6.0)-methanol (4∶6) recommend in state chemicals standard technique (Method A).The contents of ethylparaben-contained sample and ethylparaben-free sample determined by HPLC were compared with those determined by Method A.RESULTS:There was no significant difference in the content of ethylparaben-free sample between the two determination methods,but the content of ethylparaben-contained sample determined by Method A was higher than both the labeled amount and that determined by the improved method.CONCLUSION:The improved method is applicable for the content determination of lincomycin hydrochloride eye drops.

OBJECTIVE: To study the effects of Yiqi Huayu Recipe on neural cell adhesion molecule (N-CAM) in neuromuscular junctions during nerve regeneration in rats with lumbar nerve root compression. METHODS: The rats with lumbar nerve root compression were given Yiqi Huayu Recipe for 10, 20 and 30 days respectively. The distribution of N-CAM in neuromuscular junctions of soleus muscle in rats was examined with immunohistochemical method and confocal laser scanning microscopy technique. The acetylcholine receptor (AChR) was visualized with fluorescein-conjugated alpha-bungarotoxin (alpha-BTX). The overlap areas of N-CAM and AChR sites were measured with NIH image technique. RESULTS: The aggregates, sprouts and extensions of N-CAM in the neuromuscular junctions and the overlap areas of N-CAM and AChR sites in the Yiqi Huayu Recipe-treated group were all better improved than those in the untreated group. CONCLUSION: The expression of N-CAM is regulated according to the state of innervation for muscles. Yiqi Huayu Recipe may accelerate this nerve regeneration process.

BACKGROUND: The role of mechanical stress in the functional regulation of osteoblasts becomes an emphasis in osseous biomechanical researches recently. There are few reports on whether fluid shear stress can induce the expression of core-binding factor α1 (Cbfα1) or not and what is its rule.OBJECTIVE: To investigate the effects of fluid shear stress (FSS) on the gene expression of Cbfα1 in human osteosarcoma cells.DESIGN: A controlled observation experiment.SETTING: Department of Aerospace Biodynamics, Faculty of Aerospace Medicine, Fourth Military Medical University of Chinese PLA.MATERIALS: Subjects were human osteosarcoma cells (MG-63) METHODS: This study was carried out at the Department of Aerospace Biodynamics, Faculty of Aerospace Medicine, Fourth Military Medical University of Chinese PLA from November 2004 to April 2005. ①After cultured for 60 hours, MG-63 were treated with 0.5 Pa (0.5 Pa stress treated group ) or 1.5 Pa (1.5 Pa stress treated group ) FSS in a flow chamber for 15, 30, 60minutes, respectively. Cover glass was put in the Petri dish containing culture medium at the same time, serving as the control group of FSS treated group. ②The total RNA in cells was isolated. Reverse transcription polymerase chain reaction analysis was made to examine the gene expression of Cbfα1 mRNA. The ratio of Cbfα1 mRNA and GAPDH mRNA was calculated.MAIN OUTCOME MEASURES: The mRNA expressions of Cbfα1 at different FSS and different time.RESULTS: ① Compared with control group, Cbfα1 mRNA expression increased significantly at 30 and 60 minutes with the treatment of FSS.Within certain time range (15 to 60 minutes), Cbfα1 mRNA expression was strengthened with the elongation of time and the increase of stress level. ②The Cbfα1 mRNA expression at 30 and 60 minutes were significantly increased in 1.5 Pa stress treated group in comparison with 0.5 Pa stress treated group (P＜0.01).CONCLUSION: FSS can significantly increase the gene expression of Cbfα1 in human osteosarcoma cells.

BACKGROUND: The mRNA expression of α1 chain of type I collagen (COL- Iα1)in rat osteosarcoma (ROS17/2.8) induced by bone morphogenetic protein-2(BMP-2)was reduced under simulated weightlessness. The protein kinase MEK1 in the signal pathway of mitogen-activated protein kinase (MAPK) plays an important role in the expression of COL- I αl mRNA regulated by BMP-2. But there was no report on the kinase activity of MEK1 under simulated weightlessness.OBJECTIVE: To investigate the effects of simulated weightlessness on the activity of MEK1 induced by BMP-2 in ROS17/2.8 cells.DESIGN: A non-randomly control study was conducted.SETTING: Department of Aerospace Biodynamics, Fourth Military Medical University of Chinese PLAMATERIALS: Rat osteosarcoma osteoblast-like cell METHODS: This experiment was conducted at the Laboratory of Aerospace cells and Molecular Biology Laboratory , Institute of Space Medico-Engineering between August 2002 and January 2003. ROS17/2.8 cells were cultured in 1 G control and rotating clinostat simulated weightlessness for 24 hours, 48 hours and 72 hours. The cells were divided into 7 groups as follows: Group 1 was blank control group in which ROS17/2.8 cells were cultured in 1 G condition without BMP2; Group 2, cells were cultured in 1 G for 24 hours;Group 3,in weightlessness for 24 hours; Group 4, in 1 G for 48 hours; Group 5, in weightlessness for 48 hours;Group 6,in 1 G for 72 hours;Group 7,in weightlessness for 72 hours. Cells in Group 2 to Group 7 were all cultured with BMP-2. BMP-2 (500 mg/L) was added into the medium 1 hou before the culture ended. Then the total protein of cells was extracted and the kinase activity of MEK1 was detected by means of Western Blotting.MAIN OUTCOME MEASURES: The content of total ERK1/2 and phosphated-ERK1/2 (p-ERK1/2) protein in the cells RESULTS: ①Total ERK1/2 expression induced by BMP-2 in ROS17/2.8 cells under simulated weightlessness: The total ERK1/2 expression induced by BMP-2 in cells in all the groups showed no significant differences ② Phosphated-ERK1/2 expression induced by BMP-2 in ROS17/2.8 .cells under simulated weightlessness: There was little protein of p-ERK1/2 in ROS17/2.8 cells in Group 1 cultured without BMP-2 in 1 G for 24 hours. The content of p-ERK1/2 in ROS17/2.8 cells in Group 2 cultured with BMP-2 in 1 G for 24 hours was much more than that in Group 1 (P ＜ 0.01). The level of p-ERK1/2 was much lower in simulated weightlessness groups than that in 1 G control groups at the same time point. In other words, the content of p-ERK1/2 in Groups 3, 5 and 7 was respectively lower than that in Groups 2, 4 and 6 (P ＜ 0.01).The expression of p-ERK1/2 showed-a tendency of gradually decreasing in Groups 3, 5 and 7 with the prolongation of time of simulated weightlessness(P ＜ 0.01 ).CONCLUSION: The kinase activity of MEK1 in MAPK signal pathway induced by BMP-2 is reduced under simulated weightlessness.