Objective: To investigate the preliminary screening results of Alzheimer's disease (AD) among the elderly in Ningbo City, Zhejiang Province and analyze the influencing factors, so as to provide insights into prevention and control of AD in the elderly. Methods: A multi-stage stratified proportional sampling method was used to select the registered residents aged 60 years and older in Ningbo City as subjects. Demographic characteristics, lifestyle factors, physical conditions and social activities of the subjects was evaluated with questionnaires. AD was screened using the Mini-Mental State Examination (MMSE), and factors affecting the positive rate of AD preliminary screening were identified using a multivariable logistic regression model. Results: A total of 34 027 elderly residents were investigated, with an mean age of (71.71±6.89) years. There were 15 115 males (44.42%) and 18 912 females (55.58%), 16 146 residents living in rural areas (47.45%) and 17 881 residents living in urban areas (52.55%). The positive rate of AD preliminary screening was 7.28% (2 476 cases). Multivariable logistic regression analysis showed that age (70 to 74 years, OR=1.357; 75 to 79 years, OR=1.807; 80 to 84 years, OR=2.782; 85 years and older, OR=4.907), gender (female, OR=1.118), residence (urban areas, OR=0.713), marital status (unmarried, OR=3.078; widowed/separated/divorced, OR=1.301), educational level (primary school, OR=0.629; junior high school and above, OR=0.609), occupation before retirement (others, OR=0.741), family genetic history (no, OR=0.651), household disposable monthly income (1 000 to 1 999 Yuan, OR=0.636; 2 000 to 2 999 Yuan, OR=0.569; 3 000 Yuan and above, OR=0.448), exercise (seldom, OR=0.855; regular, OR=0.780), number of chronic diseases (2~5, OR=1.328), hearing loss (no, OR=0.764), smell loss (no, OR=0.615), chronic constipation (no, OR=0.696), major negative life events (no, OR=0.804), subjective memory loss (no, OR=0.583), sleep quality (general, OR=0.640; good, OR=0.616), living style (living with spouse, OR=0.300; living alone, OR=0.315; living with children, OR=0.350) and social activities (2-3 times/week, OR=0.584; 4 times/week and more, OR=0.409) were factors affecting the positive rate of AD preliminary screening. Conclusions The positive rate of AD preliminary screening among the elderly in Ningbo City is relatively high. Age, gender, economic conditions, exercise, social activities and physical conditions were factors affecting the positive rate of AD preliminary screening.

Objective:To investigate whether propofol can cause injury to hippocampal mitochondria in neonatal rats and the regulation of excitatory amino acid receptor AMPA receptor.Methods:Forty-eight Sprague-Dawley (SD) rats aged 7 days were randomly divided into control group, propofol group, propofol+AMPA receptor agonist AMPA group (propofol+AMPA group) and propofol+AMPA receptor inhibitor CNQX group (propofol+CNQX group), with 12 rats in each group. The rats in the propofol groups were intraperitoneally injected with 30 mg/kg propofol, while in control group with 3 mg/kg normal saline. Each group was given 1/2 of the first dose every 20 minutes after the first administration, three times a day, for three consecutive days. The rats in the propofol+AMPA group and the propofol+CNQX group were injected with 1 g/L AMPA or CNQX 5 μL through left ventricle after the first administration. Three days after administration, the rats were sacrificed to obtain brain tissue. Western blotting was used to determine the expression of AMPA receptor glutamate receptors (GluR1, GluR2) subunit totally (T) and on membrane (M) in hippocampus. The expression of dynamin-related protein-1 (DRP-1) and phosphorylated-DRP-1 (p-DRP-1) and mitofusin 2 (Mfn2) related to mitochondrial fission and fusion were determined. The adenosine triphosphate (ATP) content and ATPase activity were determined.Results:Compared with the control group, GluR1 expression and its M/T ratio were significantly increased after treatment of propofol, GluR2 expression and its M/T ratio were significantly decreased, the ATP content and ATP-related enzyme activity were decreased significantly, while the expression of DRP-1 and its phosphorylation was significantly increased, and the expression of Mfn2 was significantly decreased. The changes indicated that repeated intraperitoneal injection of 30 mg/kg propofol leading to the injury of mitochondria in neural cells. Compared with the propofol group, the GluR1 expression and its M/T ratio further increased after AMPA agonist administration [T-GluR1 protein (T-GluR1/β-actin): 2.41±0.29 vs. 1.72±0.11, M-GluR1 protein (M-GluR1/β-actin): 1.18±0.15 vs. 0.79±0.09, M/T ratio: 0.78±0.12 vs. 0.46±0.08, all P < 0.01], GluR2 expression was significantly increased [T-GluR2 protein (T-GluR2/β-actin): 0.65±0.13 vs. 0.30±0.14, P < 0.01; M-GluR2 protein (M-GluR2/β-actin): 0.17±0.05 vs. 0.13±0.07, P > 0.05], but its M/T ratio was further decreased (0.27±0.10 vs. 0.41±0.08, P < 0.05). The ATP-related enzyme activity was further decreased, and the ATP content was further decreased (μmol/g: 0.32±0.07 vs. 0.70±0.10, P < 0.01). Mitochondria DRP-1 expression and its phosphorylation were further increased [DRP-1 protein (DRP-1/GAPDH): 2.75±0.36 vs. 1.70±0.19, p-DRP-1 protein (p-DRP-1/GAPDH): 0.99±0.14 vs. 0.76±0.15, both P < 0.05], and Mfn2 expression was further decreased (Mfn2/GAPDH: 0.23±0.12 vs. 0.54±0.12, P < 0.05). This indicated that the AMPA agonist increased the expression of the AMPA receptor GluR1 subunit on the cell membrane and shifted the GluR2 into the cell, thus increasing the mitochondrial injury caused by propofol. Compared with the propofol group, the GluR1 expression and its M/T ratio decreased significantly after AMPA inhibitor administration [T-GluR1 protein (T-GluR1/β-actin): 0.99±0.14 vs. 1.72±0.11, M-GluR1 protein (M-GluR1/β-actin): 0.21±0.07 vs. 0.79±0.09, M/T ratio: 0.21±0.07 vs. 0.46±0.08, all P < 0.01], the change of GluR2 expression was not significant, but its M/T ratio was significantly increased (0.59±0.09 vs. 0.41±0.08, P < 0.05). The ATP-related enzyme activity was increased significantly, and the ATP content was increased significantly (μmol/g: 0.87±0.12 vs. 0.70±0.10, P < 0.05). Mitochondria DRP-1 expression and its phosphorylation were significantly decreased [DRP-1 protein (DRP-1/GAPDH): 1.18±0.17 vs. 1.70±0.19, p-DRP-1 protein (p-DRP-1/GAPDH): 0.37±0.10 vs. 0.76±0.10, both P < 0.05], and Mfn2 expression was significantly increased (Mfn2/GAPDH: 0.78±0.10 vs. 0.54±0.12, P < 0.05). This indicated that AMPA inhibitor promoted the movement to the cell membrane of GluR2 subunits meanwhile inhibited the expression of GluR1 subunits, thus alleviating the injury of mitochondrial caused by propofol in the brain. Conclusions:Repeated intraperitoneal injection of 30 mg/kg propofol for 3 days can increase the expression of GluR1 subunits of AMPA receptor in 7-day neonatal rats hippocampus mainly distributing in the cell membrane, decrease the expression of GluR2 subunits moving into the cell, thus causing injury of mitochondrial function and dynamics, which can be aggravated by AMPA receptor agonist and alleviated by AMPA receptor inhibitors.

Objective:To investigate the relationship between S-nitrosylation of spinal divalent metal transporter 1 (DMT1) modification and mechanism of remifentanil-induced hyperalgesia in rats.Methods:Forty pathogen-free healthy male Sprague-Dawley rats, aged 2-3 months, weighing 240-260 g, were divided into 4 groups ( n=10 each) using a random number table method: control group (group C), remifentanil group (group R), L-NAME group (group C+ L) and remifentanil+ L-NAME group (group R+ L). Normal saline was infused at a rate of 0.1 ml·kg -1·min -1 for 60 min via the caudal vein in C group. Remifentanil was infused at a rate of 1.0 μg·kg -1·min -1 for 60 min via the caudal vein in R group. L-NAME 30 mg/kg was intraperitoneally injected, and 10 min later normal saline was infused at a rate of 0.1 ml·kg -1·min -1 for 60 min in C+ L group. L-NAME 30 mg/kg was intraperitoneally injected, and 10 min later remifentanil was infused at a rate of 1.0 μg·kg -1·min -1 for 60 min in R+ L group. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 24 h before iv infusion and 6, 24 and 48 h after the end of infusion (T 0-3). All the rats were sacrificed under anesthesia after the last measurement of pain thresholds, and the L 4-6 segments of the spinal cord were removed for determination of the expression of neuronal nitric oxide sythases (nNOS) and DMT1 mRNA (using quantitative real-time polymerase chain reaction), extraction of nitrosylated proteins (by biotin switch assay), expression of nNOS, total DMT1 and S-nitrosylation of DMT1 (by Western blot), nitric oxide (NO) content (by spectrophotometry) and iron content (using atomic absorption spectrophotometer). Results:Compared with group C, the MWT was significantly decreased, and the TWL was shortened at T 1-3 in group R ( P<0.05), and the expression of nNOS protein and mRNA and S-nitrosylation of DMT1 was significantly up-regulated, and contents of NO and iron were increased in R and R+ L groups ( P<0.05), and no significant change was found in each index in group C+ L ( P>0.05). Compared with group R, the MWT was significantly increased, and the TWL was prolonged at T 1-3, and the expression of nNOS protein and mRNA and S-nitrosylation of DMT1 was down-regulated, and contents of NO and iron were decreased in group R+ L ( P<0.05). Compared with group C+ L, the MWT was significantly decreased, and the TWL was shortened at T 1-3, and the expression of nNOS protein and mRNA and S-nitrosylation of DMT1 was up-regulated, and the contents of NO and iron were increased in group R+ L ( P<0.05). There were no significant differences in the expression of DMT1 mRNA and total DMT1 in spinal cord among all the groups ( P>0.05). Conclusions:Activation of nNOS induces an increase in NO generation in the spinal cord and mediates the S-nitrosylation of DMT1, which may be related to the mechanism of remifentanil-induced hyperalgesia in rats.

Objective:To evaluate the effects of propofol on α-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) receptor expression in the hippocampus of neonatal rats.Methods:Eighty-four clean-grade healthy Sprague-Dawley rats of either sex, aged 7 days, weighing 14-18 g, were divided into 2 groups ( n=42 each) using a random number table method: control group (group C) and propofol group (group P). Propofol 30 mg/kg was intraperitoneally injected in group P, fat emulsion 3 mg/kg was intraperitoneally injected in group C, 1/2 of the initial dose was given at a 20 min interval, 3 times in total, for 3 consecutive days.The arterial blood samples were taken for blood gas analysis after administration on 1st day.The rats were sacrificed at 3, 7 and 28 days after the last administration of propofol, and the bilateral hippocampus was obtained for detection of the expression of AMPA receptors containing GluR1, GluR2 and GluR3 subunits in total and membrane protein (by Western blot), and the ratio of membrane protein to total protein (M/T) was calculated.The concentrations of free calcium ion were measured.The learning and memory ability was evaluated by Morris water maze test on 28 days after the last administration. Results:Compared with group C, the expression of AMPA receptor containing GluR1 subunit in total and membrane protein was significantly up-regulated, M/T was increased, the expression of AMPA receptor containing GluR2 subunit in total and membrane protein was down-regulated, and M/T was decreased at each time point ( P<0.05), no significant change was found in the expression of AMPA receptor containing GluR3 subunits ( P>0.05), the concentrations of free calcium ion in hippocampal cells were increased, and the escape latency was prolonged, the number of crossing the original platform was decreased, and the time of staying at the target quadrant was shortened at 2-4 days of training in group P ( P<0.05). Conclusion:The mechanism by which propofol reduces cognitive function is related to up-regulation of the expression of AMPA receptors containing GluR1 subunit in the hippocampus and down-regulation of the expression of AMPA receptors containing GluR2 subunits, which increases the concentration of free calcium ions in nerve cells of neonatal rats.

Remifentanil is widely used to control intraoperative pain. However, its analgesic effect is limited by the generation of postoperative hyperalgesia. In this study, we investigated whether the impairment of transmembrane protein 16C (TMEM16C)/Slack is required for α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic receptor (AMPAR) activation in remifentanil-induced postoperative hyperalgesia. Remifentanil anesthesia reduced the paw withdrawal threshold from 2 h to 48 h postoperatively, with a decrease in the expression of TMEM16C and Slack in the dorsal root ganglia (DRG) and spinal cord. Knockdown of TMEM16C in the DRG reduced the expression of Slack and elevated the basal peripheral sensitivity and AMPAR expression and function. Overexpression of TMEM16C in the DRG impaired remifentanil-induced ERK1/2 phosphorylation and behavioral hyperalgesia. AMPAR-mediated current and neuronal excitability were downregulated by TMEM16C overexpression in the spinal cord. Taken together, these findings suggest that TMEM16C/Slack regulation of excitatory synaptic plasticity via GluA1-containing AMPARs is critical in the pathogenesis of remifentanil-induced postoperative hyperalgesia in rats.

Objective To compare the function recovery of multiple injuries combined with floating knee joint injury and simple knee joint injury,and to analyze the risk factors.Methods A retrospective case control study was conducted to analyze the clinical data of 41 patients with multiple injuries combined with Blake and McBryde Ⅱ A floating knee injury admitted to Xijing Hospital of Air Force Medical University from June 2011 to June 2017.There were 26 males and 15 females,aged 18-76 years,with an average of 34.5 years.There were 25 patients with simple knee joint injury and and 16 patients with multi-joint combined injury involving knee joint and ipsilateral hip joint or ankle joint injury.Surgical fixation was performed in different parts by external fixation,intramedullary nail and plate screw fixation.According to the Kalstr(o)m and Olerud functional evaluation criteria,the excellent and good rate of postoperative functional recovery was compared between the two groups.The surgical fixation methods of the two groups were compared.Logistic regression analysis was performed on the influencing factors of functional recovery.Results The patients were followed up for 1-7 years,with an average of 3 years.The excellent and good rate of overall functional recovery in the two groups was 68％,and the rate was 84％ in simple knee injury group and 44％ in multi-joint combined injury group (P ＜ 0.01).There was no significant difference in the ratio of intramedullary nail and plate screw fixation between the two groups (P ＞ 0.05),while the proportion of the external fixation in the multi-joint combined injury group [31％ (5/16)] was significantly higher than that in the simple knee joint injury group [16％ (4/25)] (P ＜ 0.05).Logistic regression analysis showed that the rate of external fixation was an independent factor affecting the postoperative function (OR =0.15,P ＜ 0.01).Conclusions The postoperative function in multi-joint injury patients is poorer than in the single joint injury patients.The higher rate of using external fixation in multi-joint injury patients is a risk factor.For Blake and McBryde Ⅱ A floating knee injury combined with multi-joint injury,less external fixation should be used,so as to improve the postoperative function.

Objective To analyze the effects of rapid rehabilitation surgical procedures on recovery and stress response in patients undergoing hepatectomy.Methods Retrospective analysis of 60 patients with liver resection in Zhujiang Hospital of Southern Medical University from January 2012 to December 2015,40 males and 20 females.According to the rehabilitation method,it was divided into intervention group (n=30) and control group (n=30).The operation time,intraoperative blood loss,postoperative complications,and interleukin-6 (IL-6),C-reactive protein (CRP),and white blood cell count (WBC) on days 1st,3rd,and 5 th before and after surgery were compared between the two groups.Results Both groups completed the operation successfully.There was no significant difference in intraoperative blood loss and operation time between the two groups (P＞0.05).The duration of postoperative ventilation and postoperative hospitalization in the intervention group was less than that in the control group,and the incidence of postoperative complications (23.3％ vs.50.0％) and the first and second day after surgery were lower than those in the control group,with statistically significant differences (P＜0.05).On the first,third and fifth days after surgery,IL-6 and CRP in the intervention group were lower than those in the control group,respectively (64.96± 24.10) μg/L vs.(286.74±67.98) μg/L,(60.52±18.31)μg/L vs.(162.33±52.62) μg/L,(31.61± 9.42) μg/L vs.(77.44±24.54)μg/L and (24.64±17.45) mg/L vs.(41.46±20.79) mg/L,(81.11± 36.58) mg/L vs.(117.23±44.80) mg/L,(44.90±22.31) mg/L vs.(65.27±38.05) mg/L,the differences were statistically significant (P＜0.05).Conclusion The concept of rapid rehabilitation surgery applied to patients with hepatectomy can reduce postoperative stress response,reduce postoperative complications,and accelerate the recovery process.

Objective To evaluate the effect of remifentanil on iron metabolism in spinal dorsal horn neurons of rats.Methods The primary spinal dorsal horn neurons of rats were seeded in the culture plate at a density of 2× 105 cells/well and divided into 4 groups using a random number table method:control group (C group,n=40),remifentanil group (R group,n=40),divalent metal transporter 1 without iron-responsive element [DMT1 (-) IRE] siRNA group (siRNA group,n=32) and DMT1 (-) IRE siRNA plus remifentanil group (siRNA+R group,n=32).siRNA and siRNA+R groups were subjected to DMT1 (-) IRE siRNA transfection on day 3 of culture.R and siRNA+R groups were incubated for 60 min in the solution with remifentanil at a final concentration of 40 nmol/L.The contents of reactive oxygen species (ROS) and Fe2+ were determined by fluorescent probe method,the malondialdehyde (MDA) content was detected by TBA method,and the content of labile iron pool (LIP) was detected by calcein AM and iron chelator at the end of incubation with remifentanil in R and siRNA+R groups and at the corresponding time points in the other groups.The expression of DMT1 (-) IRE and DMT1 (+) IRE was determined by Westem blot in C and R groups.Results Compared with C group,the expression of DMT1 (-) IRE in the spinal dorsal horn neurons was significantly up-regulated,the contents of Fe2+,LIP,ROS and MDA were increased (P＜0.05),and no significant change was found in the expression of DMT1 (+) IRE in R group (P＞0.05).Compared with R group,the contents of Fe2+,LIP,ROS and MDA in the spinal dorsal horn neurons were significantly decreased in siRNA+R group (P＜0.05).Conclusion Remifentanil increases the iron content of spinal dorsal horn neurons by activating DMT1 (-) IRE,which may be associated with the mechanism of remifentanil-induced postoperative hyperalgesia in rats.

Objective: To evaluate the effect of 3DBody software assisted problem-based learning (PBL) teaching in orthopedic teaching. Methods: Undergraduates of clinical medicine from grade 2013 who had internship in our hospital were divided into experimental group and control group. Undergraduates in the experimental group were taught by 3DBody software assisted PBL teaching, with designed questions and the method of using 3DBody software handing to students before class. While undergraduates in the control group were taught by traditional teaching, with the use of textbooks and multimedia courseware. Examination scores of theory and probation were compared between the two groups. Questionnaires were used to evaluate the subjective perception of different teaching method among the participants in each group. Results: Scores of theoretical examination in the experimental group (84.6±5.9) were higher than those in the control group (73.2±6.1); scores of probation examination in the experimental group (17.7±2.1) were significantly higher than those in the control group (12.7±1.9); the degree of satisfaction in the experimental group (9.2±0.8) was significantly higher than that in the control group (7.2±1.3); all differences were statistically significant (P<0.05). Conclusion 3DBody software assisted PBL teaching can significantly improve the effectiveness of orthopedic teaching and enhance students' learning initiative and interest, which is worth promoting.