AIM:To study the effect of chronic corticosterone ( CORT) injection on the depression-like behav-iors and the brain glycogen level in mice.METHODS:Male C57BL/6N mice (n=40) were randomly divided into nor-mal control group and model group.The mice in model group were subcutaneously consecutively injected with CORT for 4 weeks.The mouse model of chronic stress depression was constructed.The forced swim test and open field experiment were conducted to prove chronic stress model.The serum level of CORT in the mice was measured by radioimmunoassay.The protein levels of hippocampal synaptophysin ( SYP) and brain-derived neurotrophic factor ( BDNF) were detected by West-ern blot.Hippocampus glycogen, glycogen synthase and glycogen phosphorylase were determined by indirect fluorescence measurement.RESULTS:Compared with normal control group, the immobility time of the forced swim test in model group was significantly lengthened (P<0.01), and the ability of spontaneous activity was reduced (P<0.01), indicating that chronic CORT injection induced depression-like behaviors in mice.The CORT level increased significantly (P<0.01) in model group.CORT injection decreased the protein expression of hippocampal SYP and BDNF (P<0.01), reduced hipp-ocampal glycogen level (P<0.05) and glycogen synthase activity (P<0.05), and increased glycogen phosphorylase ac-tivity (P<0.05).CONCLUSION:Chronic CORT injection causes hippocampal neuron damage and induces the depres-sion-like behaviors of mice, which may be associated with decreasing hippocampal glycogen level by CORT.

Objective To probe into the characteristics of men who have sex with men living in small-medium sized cities and provide scientific foundation for the formulation of strategy for AIDS prevention and control.Methods A qualitative survey was carried out by convenience sampling for thirty one selected MSM.Results Interviewees had a large age gap,widely different occupations and various degrees of education;they depended mainly on internet and friends' contacts to find their sex partners;their knowledge about HIV/STDs was poor and they were indifferent to the risk of AIDs,but were faced with enormous psychological pressure.Multiple sex partners,unprotected anal intercourse were their main high risk behaviors,and they hoped to have access to free condoms,free HIV detection and hot line consultation.Conclusion To implement prevention in an effective manner,close attention should be paid to the role of key persons within the MSM group,to increasing knowledge of the target population,to protecting their mental health and to creating a friendly social environment for their existence and effective use of internet.

BACKGROUND:In the fluorine-containing acidic environment, it is unclear whether Damon copper- nickel-titanium arch wire can have a corrosion resistance similar to conventional nickel-titanium arch wire and whether copper ion wil affect its corrosion resistance. OBJECTIVE: To evaluate the corrosion resistance of 3M nickel-titanium arch wires and Damon copper-nickel-titanium arch wires in artificial saliva with different fluoride and pH. METHODS:Potentiodynamic polarization curves of 3M nickel-titanium arch wires and Damon copper-nickel-titanium arch wires were measured in four kinds of artificial saliva (pH=7; pH=7, 0.2% fluoride; pH=7, 0.5% fluoride; pH=5, 0.5% fluoride). Then, the corrosion potential, corrosion current density and polarization resistance were acquired, and scanning electron microscope was used for morphological observation after corrosion. RESULTS AND CONCLUSION: In neutral (pH=7) artificial saliva, 0.2% fluoride ions added could shift up the Damon specimen polarization curve, increase the corrosion cerrent density and reduce the polarization resistance (P < 0.05); under the scanning electron microscope, corrosion was observable on the specimen surface. But 3M specimen polarization curve did not move, corrosion current density and polarization resistance substantialy unchanged (P > 0.05), and no significant corrosion was produced. When fluoride concentration was increased to 0.5%, the polarization curves of two kinds of the specimens moved, the corrosion cerrent density increased, the polarization resistance decreased (P < 0.05), and there was significant presence of corrosion on the specimen surface. When pH=5, corrosion phenomenon was more pronounced. These findings suggest that low concentrations fluoride cannot affect corrosion resistance of 3M arch wire, but can reduce the corrosion resistance of Damon arch wire; high concentrations of fluoride and acid can both reduce their corrosion resistance. In addition, the corrosion resistance of 3M arch is stronger than that of Damon arch wire.

Objective To study the effects of long-term injection of corticosterone (CORT) on the hippocampal astrocytes and synaptic plasticity in mice.Methods Male C57BL/6N mice (n=40) were randomly divided into control group and model group.Mice in the model group were treated with subcutaneous injection of CORT for 4 weeks to generate chronic stress depression model.Chronic stress model was proved to be established by tail suspension test and sucrose preference test and serum level of CORT was determined by radioimmunoassay.Protein expression levels of hippocampal synaptophysin (SYP) and postsynaptic density-95 (PSD-95) were detected by Western blot.Somal volume and protrusion length of glial fibrillary acidic protein-positive astrocytes were assayed by immunocytochemistry and quantitative stereological techniques.Results Immobility time in model group ((137.95±6.22) s) was significantly extended in comparison with that in the control group ((114.05 ± 4.12) s) (P＜ 0.01).Sucrose preference in the model group (62.42 ± 6.75)％ was lower than that in the control group (86.52±5.08)％ (P＜0.01).CORT levels in model group ((11.48±0.62) ng/ml) was significantly increased compared with that in the control group ((1.11±0.05) ng/ml) (P＜0.01).Hippocampal SYP (0.54±0.04) and PSD-95 (0.57±0.07) expression levels in model group were lower than those in the control group (0.99±0.14),(1.03±0.10) (P＜0.01).Somal volume in the model group ((132.04±9.23) μm3) and protrusion length ((1.39± 0.05) × 107 μm) was lower than that in the control group ((168.49±9.01)μm3),(1.77±0.10) × 107 μm) (P＜0.05,P＜0.01).SYP and PSD-95 expression level was found to be positively correlated with the reduction of the protrusion length(r=0.660,P＜0.01;r=0.614,P＜0.01)in astrocytes.Conclusion The results suggest that depression-like behavior-in-duced by long-term CORT treatment is possibly caused by the alternation of the synaptic plasticity associated with the reduction of the reducing the protrusion length.

Objective To establish the pharmacodynamic model of sevoflurane with bispectral index (BIS) as the effective index in pediatric patients.Methods Thirteen ASA physical status Ⅰ or Ⅱ pediatric patients,aged 4-9 yr,weighing 12-39 kg,undergoing non-cardiac surgery,were selected in the study.The pediatric patients sequentially inhaled 1％,5 ％ and 1％ sevoflurane via a face mask and each concentration was inhaled for 15 min.BIS value,HR,BP and SpO2 were automatically recorded every 10 s.Based on nonlinear mixed effect modeling,the population pharmacodynamic model of sevoflurane was established using NONMEM software.The effect of age on the pharmacodynamic parameters was evaluated using a stepwise forward addition then backward elimination modeling approach.The standard for model improvement was defined as a decrease in the value of the objective function by more than 3.84.Results Twelve pediatric patients,aged 4.0-8.5 yr,weighing 12.8-38.0 kg,with body height of 92-135 cm,were enrolled in this study and the data which were enrolled comprised 2964 effective concentration-time-BIS points.The model was not improved significantly with any covariates (age,body height,and body weight) introduced (P ＞ 0.05).The estimated parameters of the final pharmacodynamic model of sevoflurane were as follows:ke0 =O.516/min ; EC50 (BIS50) =2.11％ ; γ =2.46 ; E0 =74.6 ; EMAx =11.2.Conclusion The pharmacodynamic model of sevoflurane is successfully established with BIS as the effective index in pediatric patients,and the analysis for each parameter of the model indicates that the sensitivity to sevoflurane is lower,but the blood-brain equilibration time of the drug is shorter and the onset and recovery are faster in children than in adults.

Objective To explore the effects of electroacupuncture at Shenting (DU24) and Baihui (DU20) on learning and memory ability in the cerebral ischemia-reperfusion rats and its possible mechanism. Methods 45 male Sprague-Dawley rats were randomly divided into sham group (n=15), ischemia group (n=15) and electroacupuncture group (n=15). The latter 2 groups were modeled as focal cerebral ischemia-reperfusion injury, and the electroacupuncture group received electroacupuncture at Shenting (DU24) and Baihui (DU20) for 7 days. They were tested with Morris Water Maze, observed with Nissl's staining. The protein expression of RhoA was detected with Western blotting. Results The learning and memory ability improved in the electroacupuncture group (P<0.05), the injury of the neurons reduced (P<0.05) and the expression of RhoA in hippocampus decreased compared with the ischemia group (P<0.05). Conclusion Electroacupuncture could ameliorate the learning and memory ability in ischemia- reperfusion rats, which may relate with the inhibition of the expression of RhoA in hippocampus.

Non-alcoholic fatty liver disease(NAFLD) has become the main cause of chronic liver disease in children worldwide, and the incidence of NAFLD shows an increasing trend year by year. The risk factors leading to the onset of NAFLD in children are diversified and different from those in adults. At present, most medical institutions still pay little attention to NAFLD in children. This paper summarizes the risk factors and mechanisms for NAFLD in children, including gene polymorphism, maternal and fetal conditions, diet and living habits, environmental exposure, metabolic syndrome, endocrine-related mechanisms and intestinal microecology, in order to provide reference for the prevention and management of childhood NAFLD.

Objective To explore the effects of electroacupuncture at Baihui (DU20) acupoint on learning and memory and its possible mechanism through the expression of brain-derived neurotrophic factor (BDNF) in APP/PS1 double-transgenic mice. Methods 30 female APP/PS1 double transgenic mice were randomly divided into model group, DU20 group and non-acupoint group, and 10 wild type mice con-sisted of wild group. DU20 group received electroacupuncture at Baihui and the non-acupoint group received electroacupuncture at non-acu-point for 28 days. Learning and memory was tested by Morris water maze. Deposition ofβ-amyloid (Aβ) peptide was determined by immu-nohistochemical staining. The expression of BDNF in cortex was examined by RT-PCR and Western blotting. Results Compared with the model group, DU20 group ameliorated the learning and memory ability of APP/PS1 double-transgenic mice (P<0.05), decreased the deposi-tion of Aβpeptide (P<0.05) and upregulated the gene and protein levels of BDNF (P<0.01). There was no significant difference between the model group and non-acupoint group (P>0.05). Conclusion Electroacupuncture at DU20 acupoint could ameliorate learning and memory in APP/PS1 double-transgenic mice. The mechanism may be related to increase the expression of BDNF and decrease the deposition of Aβ.

Objective To examine the relationship between CCT 5 ,γδ T cell and autoimmune diseases .Methods Recombinant CCT5 protein was cloned , expressed and purified in E.coli.Three peptides of CCT5 protein were used to prepare for anti-CCT5 monoclonal antibodies .Purified CCT5 protein was used to expand γδT cells from pe-ripheral blood mononuclear cells (PBMC).Plasma level of CCT5 in healthy donors, patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) were detected by ELISA assays .The correlation analysis between plasma CCT5 concentration and the percentage of different subtypes of γδT cells measured by flow cytometry was made . Results The CCT5 gene was amplified by PCR and the length of the target fragment was 1 750 bp.The expressed 65 ku CCT5 protein was purified and validated by SDS-PAGE.Two paired monoclonal anti-CCT5 antibodies were screened to detect CCT5 protein in plasma.Immobilized recombinant CCT5 protein was able to induce specific sig-nificant amplification of peripheral γδT cells.Correlation analysis of 10 healthy donors indicated significant corre-lation between the plasma CCT 5 concentration and the proportion of Vγ9 and Vδ2 γδ T cells.The plasma CCT5 concentration significantly decreased in autoimmune diseases patients , including RA and SLE .Conclusions These data suggest that CCT 5 could be a novel Vγ9δ2 γδT cell-related factor in autoimmune diseases , which deepen the understanding of Vγ9δ2 γδT cell function in autoimmune diseases .

OBJECTIVE: To study anti-inflammatory effect and mechanism of the luteolin · 4, 4' -dipyridy co-crystal.METHODS: Using macrophage RAW264. 7 of normal mice as control, the inflammation model was established with lipopolysaccharide (LPS) -induced RAW264. 7 cells. MTT assay was used to detect cells activity 2 h after treatment of different concentrations of luteolin (10, 20, 40, 80 μmol/L), 4, 4' -dipyridy (10,20, 40,80 μmol/L) and luteolin·4, 4' -dipyridy co-crystal (10, 20, 40, 80 μmol/L). The mRNA expression of iNOS and COX-2 in RAW264. 7 cells at 40 μmol/L were determined by qRT-PCR. The protein expression of TNF-α and IL-6 in RAW264. 7 cells at 40 μmol/L were determined by ELISA. The protein expression of NF-κB p65 in RAW264. 7 cells at 40 μmol/L were determined by Western bolt. RESULTS: Compared with normal cells, the activity of RAW264. 7 cells was decreased significantly after induced by LPS (P<0. 01); mRNA expression of iNOS and COX-2, protein expression of TNF-α, IL-6 and NF-κB p65 were increased significantly (P<0. 01). Both luteolin and luteolin · 4, 4' -dipyridy co-crystal could enhance the activity of RAW264. 7 cells after induced by LPS (P<0. 05 or P<0. 01) in concentration-dependent manner. 4, 4' -dipyridy had no significant effect on the activity of RAW264. 7 cells after induced by LPS. After luteolin and luteolin· 4, 4' -dipyridy co-crystal at 40 μmol/L, mRNA expression of iNOS and COX-2, protein expression of TNF-α, IL-6 and NF-κB p65 in RAW264. 7 cells after induced by LPS were decreased significantly (P<0. 05 or P<0. 01); the luteolin · 4, 4' -dipyridy co-crystal was better than luteolin (P<0. 05 or P<0. 01). CONCLUSIONS: The luteolin·4, 4' -dipyridy co-crystal can inhibit the generation of inflammatory factors by down-regulating NF-κB signal, and its anti-i nflammatory effect is better than luteolin.