Mechanisms of UV-B-induced apoptotic regulation in yeast Saccharomyces cerevisiae were studied. The results showed that UV-B irradiation indeed inhibited the growth of yeast cells as well as induced extensive apoptosis during 96 h experiment period. However, survival of 96 h irradiated cells remained 10% while most control cells finally dead after re-growth under UV-B irradiation for 12 d. And by exposed to 0.01 mol/L or 0.1 mol/L H2O2 for 30 min, survival rate of 24 h irradiated cells were 3.0-fold or 3.2-fold than control, respectively. By to heat shock for 30 min or 60 min, survival rate of 24 h irradiated cells were 3.5-fold or 9.0-fold than control, respectively.

BACKGROUND: Shuangshen oral liquid consisting of renshen and danshen is firstly used to treat glucocorticoid-induced osteoporosis. OBJECTIVE: To establish a rat osteoporosis model through glucocorticoid and to observe the preventive effects of shuangshen oral liquid (SS) on bone substance and bone mass. DESIGN, TIME AND SETTING: A completely randomized controlled grouping animal experiment was performed in the Animal Experimental Center and Department of Pharmacology, Guangdong Medical College from June to September in 2008. MATERIALS: High-dose SS consisted of 3.6 kg danshen, 5 kg renshen, and then prepared by water extraction twice, and the concentration was 870g/L. On this basis, high-dose SS was diluted three times to obtain low-dose SS with a concentration of 290 g/L. The prednisone acetate raw medicine was purchased from Zhejiang Xian Ju Pharmaceutical Co., Ltd. METHODS: Thirty-two 3-month-old male SPF rats were randomly divided into 4 groups, and every group had 8 rats. The normal control group rats were fed with distilled water 5 mL/(kg?d) by gavage. Rats in prednisone group were treated with 0.7 g/L prednisone suspension (5 mL/kg per day) by gavage. SS group rats were treated with 0.7 g/L prednisone suspension (5 mL/kg per day) by gavage and then given the high does and low does SS (5mL/kg per day) respectively by gavage 3 hours later. The rats were sacrificed by heart hemospasia 88 days later. MAIN OUTCOME MEASURES: Body mass, bone mineral content and bone hydroxyproline content per unit bone, bone mineral density in the left femur, biomechanics indexes of the right femur. RESULTS: The long-term administration of prednisone restrained the increasing of rats body mass (P

BACKGROUND: It has been demonstrated that electromagnetic field (EMF) can adjust proliferation and differentiation of bone marrow mesenchymal stem cells, but the specific mechanism is not clear. OBJECTIVE: To investigate the effects of EMF-activated ERK1/2 pathway on proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells.METHODS: The 3rd passage of rat bone marrow mesenchymal stem cells were received EMF treatment (15 Hz, 1 mT, sine wave), 20 μmol/L PD98059 + EMF treatment, or only PD98059 treatment. Simultaneously, a normal control group was established. Western blotting was applied to detect the activation of ERK signal pathway after EMF exposure. MTT assay was used to determine the activation of proliferation of cells. And alkaline phosphatase (ALP) activity in cells was detected by an ALP kit. RESULTS AND CONCLUSION: The ERK1/2 phosphorylation, proliferation and ALP activity of rat bone marrow mesenchymal stem cells were remarkably increased after exposure to EMF (P < 0.01). PD98059 could effectively block the increasing of ERK1/2 phosphorylation and cell proliferation (P < 0.01), but elevate ALP activity in a certain level (P < 0.01). EMF stimulation can fast activate ERK1/2 signal pathway and then promote the proliferation of rat bone marrow mesenchymal stem cells, however, ERK1/2 signal pathway activation has a less effect on osteogenic differentiation of bone marrow mesenchymal stem cells.

Objective To observe the changes of extracellular matrix(ECM) production and hypertrophy of glomerular mesangial cells(GMCs) induced by high glucose(HG),and the inhibitory role of myriocin(ISP-1).Methods GMC cultured with normal glucose(5.6 mmol/L D-Glucose,NG),HG(25.2 mmol/L D-Glucose) and HG plus ISP-1(100 mg/L) for different durations(0,24,48,(72 h)).The sizes of GMC were indicated by forward scatter intensity,measured by flow cytometery,and the levels of fibronection(FN),collagen Ⅳ(Col Ⅳ),laminin(LN),precollagen Ⅲ(Pcol Ⅲ) and hyaluronic acid(HA) in the supernatant of cultured GMC were detec-(ted) by ELISA.Results Compared with NG,HG could induce GMC hypertrophy(P

Objective To study the effects of electromagnetic field (EMF) on the activation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) pathways in mesenchymal stem cells (MSCs) and their interaction, and to explore the cellular signal transduction mechanism of the biological effects induced by EMF.Methods The 3rd-passage rat bone marrow MSCs were randomly divided into a control group, an EMF group, an EMF + PD98059 group and an EMF + SB202190 group.Cells in the EMF group were cultured in the electromagnetic field, those in the EMF + PD98059 and EMF + SB202190 groups cultured in the electromagnetic field after PD98059 or SB202190 was added, and those in the control group were cultured normally.Different groups of cells were exposed to electromagnetic fields (15 Hz, 1 mT, sine wave form) for different exposure duration.The activated phosphorylated and non-phosphorylated p38MAPK were measured using Western blotting analysis with their specific corresponding antibodies.The alkaline phosphatase (ALP) activity in cells in different groups was detected according to the instructions of ALP kit.MTT assay was applied to investigate the proliferation of cells.Results Electromagnetic fields could rapidly induce the activation of p38 MAPK (P ＜ 0.05) and the phosphorylation of p38 MAPK elevated after 15 min exposure to EMF.The phosphorylation of p38 MAPK was significantly lower in the EMF + SB202190 group than that of the EMF group.After 5 days of EMF exposure, the ALP activity of cells was significantly improved, and the effect could be inhibited by SB202190.The bone marrow mesenchymal stem cells proliferation increased significantly after being exposed to EMF for 3 days, and it could not be blocked by SB202190.Phosphorylation of ERK and MAPK increased significantly when the p38 MAPK pathway was blocked by SB202190 and exposed to EMF for 5 minutes, and it also increased significantly when the ERK MAPK pathway was blocked by PD98059 and received 30 minutes of EMF exposure.Conclusion EMF can quickly activate ERK and p38 MAPK pathways to induce cell proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells.Moreover, in EMF there is a mutual interference between ERK and p38 MAPK pathways.

Objective To investigate the feasibility,safety and efficacy of laparoscopic and endoscopic cooperative surgery (LECS) for elderly patients with gastric gastrointestinal stromal tumor (GIST).Methods 54 cases with GIST aged 65 years and over in Department of Gastrointestinal Surgery in Beijing Hospital from Dec.2008 to Dec.2012 were selected.31 cases underwent LECS and 23 cases underwent open surgery.Clinical data including operation time,intraoperative blood loss,complications,tumor size,length of incision,postoperative gastrointestinal function recovery time,postoperative in hospitalization and follow up data were retrospectively analyzed in patients.Results There were 17 males and 14 females in the LECS group,and the mean age was (72.8±5.9)years.29 patients underwent laparoscopic-assisted partial gastrectomy,and 2 cases underwent laparoscopicassisted endoscopic dissection in LECS group.All operations were successful with no conversion to open surgery and death.There were 13 males and 10 females in the open surgery group,and the mean age was(73.3±6.1)years.The mean operation time was longer in LECS group than in open surgery group [(120.6±32.8) min vs.(86.3±33.5) min].The mean intraoperative blood loss,mean tumor size,mean length of incision,mean time of gastrointestinal function recovery,mean postoperative hospitalization were less or smaller in LECS group than in open surgery group [(40±23.4) ml vs.(130±65.6) ml,(2.3±1.2)cm vs.(3.6 ±1.8)cm,(3.6±1.1) cm vs.(14.4±3.5) cm,(47.7± 10.4)h vs.(61.4±11.9)h,(5.1±2.3)d vs.(7.2±2.5)d,respectively,t=3.192,1.831,5.212,2.014,3.519,P=0.002,0.012,0.000,0.015,0.001].According postoperative tumor risk assessment,13 cases were at very low risk,15 cases at low risk and 3 cases at middle risk in LECS group; 4 cases were at very low risk,14 cases at low risk and 5 cases at middle risk in open surgery group.The risk degree was lower in LECS group than in open surgery group (x2 =5.63,P=0.017).During a follow-up of 5 53 months,death without GIST was found in 5 patients in LECS group and 4 cases in open surgery group.Hepatic metastasis was found in 1 case in open surgery group.Conclusions LECS is a safe and feasibility alternative approach for elderly patients with gastric GISTs.It has more minimal invasion,fast recovery and satisfaction with short term outcomes as compared with conventional open surgery.

Objective To investigate the clinical features and causes of micturition and defecation dysfunction in motor neuron disease (MND) patients.Methods The micturition and defecation function was evaluated by a questionnaire covering storage and voiding of urine and feces respectively in 50 MND patients.The clinical features and external anal sphincter electromyography (EAS-EMG) were analyzed to explore the causes of micturition and defecation dysfunction in MND patients.Results Micturition and defecation dysfunction was detected in 9 of 50 (18.0％) MND patients.The main types of micturition and defecation dysfunction were constipation (4/9),urinary frequency,urgency with or without incontinence,fecal urgency (4/9),powerlessness for micturition and defecation (2/9),hesitancy for micturition (1/9).EAS-EMG was normal in 9 MND patients accompanied with micturition and defecation dysfunction.Conclusions MND patients accompanied with micturition and defecation dysfunction were not very rare.Constipation,urgency and powerlessness were the main types of micturition and defecation dysfunction and they were not related to the function of external anal sphincter.Gastrointestinal dysfunction from abnormal autonomic nerve involvement,muscle weakness and the resulted reduced activity,severe upper motor neuron damage and respiratory muscle weakness may be the main causes of micturition and defecation dysfunction in MND patients.

Objective To analyze the clinical features and factors associated with knee osteonecrosis in patients with systemic lnpus erythematosus (SLE).Methods Medical charts of Peking Union Medical College Hospital from 2000 to 2013 were reviewed to identify patients who were diagnosed as SLE with kuee osteonecrosis.Controls were selected and matched to the cases by age and sex.The clinical and laboratory variables were compared between SLE patients who were with and without knee osteonecrosis.Numerical data and categorical data comparisons were analyzed using t-test,x2-test,respectively.Results Sixteen patients developed knee osteonecrosis that constituted 0.37％ of all the 4 301 hospitalized SLE patients during the same period.Fifteen patients were female,who developed knee osteonecrosis with an average age of 36 years (range:17-67 years).The mean duratiou of SLE before the diagnosis of knee osteonecrosis was 64±40 months (range:16-120 months).The interval from onset of symptoms to diagnosis was 0.5 to 24 months.The distal end of femur was involved in all 16 patients,while the proximal tibia necrosis also occurred in 8 patients.The detection rate of knee osteonecrosis by MRI was 100％,while it was only 19％ by plain radiography.The incidence of skin vasculitis,myositis,osteoporosis,hyperlipidemia,hypoalbuminemia and elevated serum immunoglobin G levels were significantly higher in SLE patients with knee osteonecrosis than in controls (P＜0.05).In addition,the use of anti-malarials was significantly lower in SLE patients with knee osteonecrosis than in controls (P＜0.05).Conclusion The knee osteonecrosis in SLE patients is affected by multifactors.The risk factors include skin vasculitis,myositis osteoporosis,hyperlipidemia,hypoalbuminemia and the elevated immunoglobin G level.The use of antimalarial drugs in SLE patients may protect against knee osteonecrosis development.Knee osteonecrosis coull be diagnosed early by MRI.

Objective To explore the impact of childbirth on women external anal sphincter electromyography by analysis of motor unit potentials parameters of external anal sphincter electromyography of healthy women volunteers with different childbirth experiences.Methods Twenty-eight healthy volunteers with different childbirth experiences were recruited in this study.Among them , 7 had a history of cesarean and 21 had experienced 1-3 uncomplicated vaginal deliveries ( 12 women had experienced 1, 6 had experienced 2, and 3 had experienced 3).Another 9 nulliparous healthy volunteers were recruited as control group.Among all subjects who completed the examination , parameters of motor unit potentials ( duration, amplitude, area, mean number of turns and mean phases ) of bilateral external anal sphincter were obtained for statistical analysis.Results There were no significant differences in any of the parameters of motor unit potentials between the nulliparous group and the cesarean group , while parameters of durations (10.5 ms vs 9.0 ms, t=-2.506, P=0.019) and mean phases (4.0 vs 3.6, t =-2.707, P=0.012) of vaginal delivery group were significantly higher than that of cesarean group and parameter of durations ( 10.5 ms vs 8.9 ms, t =-3.025, P =0.005 ) of vaginal delivery group was significantly higher than that of the nulliparous group;With increasing numbers of vaginal deliveries , only the parameter of mean turns showed statistically significant differences , although there was a slight trend of larger and more complex motor unit potentials.Compared with subjects without vaginal delivery experience ( including nulliparous group and the cesarean group ) , the parameters of durations and mean phases of subjects with vaginal delivery experience were statistically higher; Nevertheless , parameter of bilateral duration of the motor unit potential preferred asymmetric.Conclusions Childbirth experience has an explicit impact on the parameters of the external anal sphincter motor unit potentials , which is considered to be strongly correlated with the vaginal delivery process rather than the pregnancy procession itself.In addition , the impact is mostly from the first vaginal delivery experience.The characters of asymmetry of motor unit potential parameters imply the possibility of mechanical damage and decrease blood perfusion of tissues during delivery procession.

BACKGROUND: It has been proved that electromagnetic field can adjust and control proliferation and differentiation of bone marrow mesenchymal stem cells v/a cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signal transduction system. However, there are few relevant reports about Ca2+ as the second messenger in application. OBJECTIVE: To study the effects of verapamil on the proliferation and differentiation of bone marrow rnesenchymal stem cells stimulated by electromagnetic fields and to conclude influx changes of Ca2+.DESIGN, TIME AND SETTING: Electrostimulative cytological observation in vitro, which was performed in Laboratory of Orthopedic Surgery, Tongji Hospital between April and June 2005.MATERIALS: Six 4-5-week SD rats of clean grade were selected in this study. Verapami| was provided by Sigma Company, USA, and Helmholtz coil-magnetic field producer was made in Department of Electric Machine, Navy Engineering University.METHODS: The bone marrow mesenchymal stem cells were isolated and cultured in vitro with adherence method and digested with trypsin. The fourth-passage cells were harvested, adjusted to 1 × 107 L-1 in density, and divided into A, B, C and D groups in 96-well plate with 200 μ I/well. Cells in the normal control group were not performed with any agent. On the second day of inoculation, cells in the magnetic field (EMF) group were cultured in Helmholtz-coil magnetic field (0.8 mT, 50 Hz) in 0.05% CO2 saturated humidity incubator at 37 ℃, 30 minutes for each, 12 hours for interval, six time in total. Cells in the verapamil group were cultured with 20 μ mol/L verapamil, and cells in the combination group were cultured with 20 μ mol/L verapamil and magnetic stimulation.MAIN OUTCOME MEASURES: Proliferative activity was tested with MTT method, content of alkaline phosphate differentiated to osteoblasts was measured, and cells were stained with modified Gomori Ca-Co staining. RESULTS: Proliferative activity was significantly increased in the EMF group as compared with that in the normal control group after 3-day magnetic stimulation (P < 0.01), but verapamil could inhibit promotive effect on proliferation. Content of alkaline phosphate in the normal control group was similar to that in the EMF group, while those two contents were significantly higher than those in the verapamil group and the combination group (P < 0.01); furthermore, content of alkaline phosphate in the combination group was significant higher than that in the EMF group (P < 0.01). Qualitative analysis of alkaline phosphate showed a coincident result as mentioned above.CONCLUSION: EMF of 50 Hz frequency and 0.8 mT intensity can change intracellular free calcium ion concentration of bone marrow mesenchymal stem cells, and the change play a key role in the cellular proliferation and play a partial role in the differentiation of bone marrow mesenchymal stem cells into osteoblasta.