Objective To investigate the exact protocol eliciting the hippocampal CA1 long-term depression (LTD) of rats in vivo and the effect of amyloid β-protein (Aβ) on the LTD.Method By applying test stimulation to Schaffer collateral in hippocampal CA1 region in rats,recorded the in vivo field excitatory postsynaptic potentials (fEPSPs) ;further,observed the induction of LTD with different low frequency stimulation (LFS) and investigated the effect of Aβ25-35 on the LTD.Results Prolonged LFS (1,5 and 10 Hz) but not paired-pulse stimulus (PPS) effectively elicited the LTD in the hippocampal CA1 region,with significantly decreased amplitude of fEPSPs after LFS ; 1 Hz 900 pulses group induced a stronger LTD,being (63.7 ± 3.8) ％ at 120 min post-LFS,lower (P ＜ 0.05) than (75.1 ± 3.2) ％ in 600 pulses group ; different frequencies (1,5 and 10 Hz) of LFS with same pulses induced similar degree of LTD,the amplitude of fEPSPs were (63.7 ± 3.8) ％,(61.2 ± 3.6) ％ and (59.8 ± 3.9) ％ respectively,without significant differences between any two groups (P ＞ 0.05) ; after applying 12.5 nmol and 25 nmol Aβ25-35,the amplitude of fEPSPs decreased to (63.2 ± 3.8) ％ and (46.8 ± 3.9) ％,respectively,and lower and than that in control ((73.9 ± 3.0) ％,P ＜ 0.05).Conclusion Prolonged LFS effectively induced in vivo hippocampal LTD of rats,which provides an important electrophysiological protocol for the study of synaptic plasticity; Aβ25-35 injection dont affect the baseline synaptic transmission,but dose-dependently enhance the in vivo hippocampal LTD of rats,indicating that Aβ-induced LTD facilitation may be involved the early impairment of learning and memory in Alzheimer's disease.

Objective To study the relationship between occupational stress and metal health of radiation workers.Methods Totally 220 radiation workers were investigated by Chinese perceived stress scales questionnaire,Chinese health questionnaire-12,as well as questionnaire related to radiology.Results The stress score of radiation worker with senior title was 18.18 ± 6.12,which was the lowest of all 220 participants.There was positive relationship between stress score and health score (r =0.484).19.1％ of the workers sometimes felt stressed due to the danger of work.Conclusions There are some significantly correlation between occupational stress and metal disorder.More attention should be paid on the occupational stress.Positive measures such as decompression and psychological intervention will be helpful to protect physical and mental health of radiation workers.

Objective:To compare the clinical effects of restrictive blood transfusion combined with hyperbaric oxygen preconditioning (HBOPC) and restrictive blood transfusion in the treatment of hip,knee arthroplasty (THA,THA).Methods:40 patients in the period of epidural anesthesia,femoral nerve hysteresis hip and knee arthroplasty were selected and randomly divided into two groups:restrictive transfusion group (maintain 80 g/L≤ Hb ＜100 g/L,n=20) and restrictive blood transfusion combined with HBOPC (HBOPC+maintain 80 g/L =Hb ＜100 g/L,n=20).The red blood cell transfusion,red blood cell transfusion rate,perioperative Hb,blood oxygen saturation (SO2),the incidence of hypotension during operation,hospitalization time and postoperative cerebral infarction,acute pulmonary embolism,pneumonia,myocardial infarction,wound infection rate and 90 days mortality rate were compared between two groups.Results:Compared with the restrictive transfusion group,the postoperative Hb,blood oxygen saturation (SO2) of restrictive blood transfusion combined with HBOPC group were significantly increased(P ＜ 0.05);the red blood cell transfusion,red blood cell transfusion rate,incidence of pneumonia,wound infection rate were significantly decreased (P＜0.05).Conclusion:Restrictive blood transfusion combined with hyperbaric oxygen preconditioning could improve the anoxic state of the hip,knee arthroplasty patients,which could effectively reduce red blood cell transfusion,reduce postoperative complications,has good clinical curative effect.

Objective To investigate the effects of levocarnitine on pregnancy outcome of the patients with obstructive azoospermia treated with intracytoplasmic sperm injection ( ICSI ) . Methods A total of 74 patients with obstructive azoospermatism treated with ICSI randomly divided into 2 groups:treatment group( n=38) , taking levocarnitine before treatment with ICSI 1 g twice a day for three months;control group( n=36) , taking vitamine E before treatment with ICSI 0.1 g twice a day time for three months.tumor necrosis factor-α(TNF-α), reactive oxygen species(ROS) level, epididymal sperm motility and morphology in epididymal fluid of the two groups were determined before and after treatments. The number of matured oocytes, fertilization, and embryos of adequate quality, the rate of fertilization and embryo of adequate quality, and pregnancy rates after PESA-ICSI were compared between the two groups. Results TNF-α in epididymal fluid before and after the treatment was (5.39±2.28)and(4.05±2.14)ng.mL-1 in the treatment group(P<0.05), and(4.97±2.13)and(4.83±2.35)ng.mL-1 in the control group.ROS in epididymal fluid before and after the treatment was(62.72±8.51),(56.28±8.70)RLU.s-1(P<0.05)in the treatment group( P<0. 05 ) , and ( 62. 61 ± 7. 55 ) and ( 61. 05 ± 6. 77 ) RLU . s-1 in the control group. After treatment with levocarnitine, epididymal sperm motility was significantly increased(P<0.05).There were no significant differences in all the indexes in the control group before and after the treatment(P>0.05).After PESA-ICSI, the number and percentage of high quality embryo in the treatment group were significantly higher than those of the control group(P<0.05). Conclusion Levocarnitine can down-regulate epididymal TNF-α and ROS in patients with obstructive azoospermatism, thereby improve the environment of the epididymis and elevate the quality of sperm and ICSI pregnancy outcome.

BACKGROUND:Preliminary studies of our research group have confirmed that the proliferation of preosteoclasts and the differentiation and function of osteoclasts could be inhibited when they were cultured in lower oxygen tension even hypoxia (2%O 2 ), but the gene expression of osteoclasts cultured in vitro have not been reported.
OBJECTIVE:To examine the effect of oxygen tension on specific gene expression of osteoclasts in vitro and explore the mechanism of osteoclast differentiation influenced by oxygen tension.
METHODS:The preosteoclasts were induced with 10μg/L macrophage colony stimulating facto and 10μg/L soluble receptor activator of nuclear factor-κB ligand into mature osteoclasts. Then the osteoclasts were cultured in normoxia, tissue oxygen and hypoxia (20%, 7%, 2%O 2 ) respectively. cells were then stained for tartarate-resistant acid phosphatase to assess osteoclastic formation. cells were col ected at 1, 2, 3, 4, 5, 6, 7 days after culture respectively. The soluble receptor activator of nuclear factor-κB ligand, tumor necrosis factor receptor-associated factor 6, tartarate-resistant acid phosphatase, and cathepsin K mRNA expression levels were determined using real-time quantitative PCR.
RESULTS AND CONCLUSION:The number of osteoclasts positive for tartarate-resistant acid phosphatase in the hypoxia was significantly lower than that in the tissue oxygen and normoxia (P<0.05). Under different oxygen tension, the mRNA expression levels of soluble receptor activator of nuclear factor-κB ligand in osteoclasts maintained unchanged. The mRNA expression levels of tumor necrosis factor receptor-associated factor 6 reached the peak at 5 days after culture in tissue oxygen and normoxia (P<0.05). The mRNA expression time of tartarate-resistant acid phosphatase and Cathepsin K were delayed accompanied by decreased oxygen tension, but the maximum were maintained in tissue oxygen. Compared with normoxia and hypoxia, osteoclasts cultured in tissue oxygen are more prone to differentiate and maintain the activity and functions.

Objective The radiotherapy is one of main treatments for patients with malignant tumor and leads to ovarian func-tion decreasing in young women .It is very important to protect ovarian function during the process of radiotherapy .The aim of this study is to investigate the effect of melatonin ( MT) agonist on radiotherapy-induced ovarian function damage in female rats . Methods Thirty SD rats were divided into five groups randomly , which received normal saline, 200 cGy radiotherapy+normal saline, 200 cGy radiotherapy+MT(25 mg/kg), 200 cGy radiotherapy+MT(50 mg/kg), and 200 cGy radiotherapy +MT(100 mg/kg), respectively.All rats were de-capitated two weeks after radiotherapy .Levels of serum follicle-stimulating hormone (FSH) and estradiol (E2) were measured by en-zyme-linked immune sorbent assay method;the number of the primordial follicles , the growth follicles and the mature follicle were ob-served;Caspase3 activity was assayed by spectrophotometry . Results In accordance with the normal control group , RT+MT (100 mg/kg) group, RT+MT (50 mg/kg) group,RT group , serum E2 levels decreased, respectively (6.68 ±0.48, 5.73 ±1.36, 4.26 ±0.44, 2.83 ±0.51)pmol/L;FSH levels increased, respectively (0.340 ±0.011, 0.431 ±0.053, 0.479 ±0.023, 0.604 ± 0.028)ng/mL ;the total number of follicles decreased ,respectively (21.67 ±1.97, 18.00 ±2.28, 15.50 ±1.05, 11.50 ±2.43);Caspase3 activity increased,respectively (0.14 ±0.03, 0.26 ±0.06, 0.36 ±0.05, 0.50 ±0.05).Except FSH had no significant difference between RT +MT(50 mg/kg)group and RT+MT(100 mg/kg) group(P>0.05), the rest indexes had significant difference between the two groups(P<0.05). Conclusion MT can diminish radiotherapy-induced ovarian damage in female rats, it may be related to the mechanism that MT inhibits the radiotherapy-induced activation of Caspase 3.

AIMTo study the chemical constituents of Evodia rutaecarpa (Juss.) Benth.

METHODSThe crude total alkaloids were enriched by acid-base treatment and solvent extraction. Isolation and purification were carried out by silica gel column chromatography and recrystallization etc. Structural determination of the pure compounds were based on physico-chemical properties and various spectral data analysis (1HNMR, 13CNMR, UV, IR, 1H-1H COSY, HMQC, HMBC, ESIMS, HREIMS, NOESY).

RESULTSFourteen compounds were obtained from Evodia rutaecarpa, ten of them were identified as evodianinine (1), rutaecarpine (2), evodiamine (3), wuchuyuamide I (4), hydroxyevodiamine (5), limonin (6), daucosterol (7), triacontanoic acid (8), nonacosane (9) and beta-sitosterol (10).

CONCLUSIONCompound 1 is a new alkaloid named evodianinine.

Alkaloids ; chemistry ; isolation & purification ; Carbolines ; chemistry ; isolation & purification ; Evodia ; chemistry ; Fruit ; chemistry ; Indole Alkaloids ; Molecular Structure ; Plant Extracts ; chemistry ; isolation & purification ; Plants, Medicinal ; chemistry ; Quinazolines ; chemistry ; isolation & purification

Objective To investigate the current situation of radiation protection in nuclear medicine diagnosis workplace.Methods The study was performed in 3 hospitals in northeast,north and central of China from February to December in 2013.The γ dose rate instrument was used to detect the workplace ambient dose equivalent rate of medicine preparation,leaching,packing,injection and imaging.Individual effective dose and equivalent dose were evaluated by photoluminescent dosimeter.Results The ambient dose equivalent rate was up to 1.92 mSv/h at repacking place and 1.2 mSv/h at injection place.The ambient dose equivalent rate of patients after injection was 5.36-240 μ,Sv/h.The hand equivalent dose was 0.01-0.02 mGy.Moreover,there were problems of staff route intersection,as well as the patients after injection staying in the public area.Conclusions Radiation workers should pay more attention to individual protection,and improve the operation proficiency to shorten the operation time.Furthermore,in order to protect public from unnecessary irradiation,there should be some changes in staff route and patients administration.

Objective To investigate the contribution of single nucleotide polymorphisms (SNP)variation in folate metabolism pathway genes and its interaction with environmental risk factors to the etiology of NTD. Methods In 275 families from central China, a total of 278 aborted fetal tissues or blood samples were collected from NTD individuals, 478 maternal and/or paternal blood samples were also obtained as controls. Folate supplementation, maternal diabetes mellitus and medication before pregnancy and during the first trimester of pregnancy were investigated. SNP analyses of all samples were performed by CEQ 8800. Case-parent control study and transmission/disequilibrium tests (TDT) were performed according to environmental cofactors stratification to evaluated 28 SNP in 12 folate pathway genes associated with human NTD. Results Only gene MTHFR rs1801133 was significantly associated with NTD, and synergistic effects of environmental risk factors (no folate supplementation and maternal diabetes) were shown on the occurrence of NTD. Linkage disequilibrium between BHMT rs3733890 and NTD existed in case of no folate supplementation,whereas the genotype alone did not contribute to the etiology of NTD. Other SNP were not significantly associated with NTD. Conclusions MTHFR rs1801133 is a risk factor of NTD, but BHMT rs3733890 is not an independent risk factor. Further investigations in folate and methionine cycle genes are requird in larger scale to enclose the interactions between gene and gene, or gene and environmental factors.

Objective To measure the circuit time constants of 4 kinds of radiation survey meters (451P ionization chamber dosimeter,6150AD6 + 6150AD-b dose meter,FH40G + FHZ672E-10 dose meter and AT1123 dose meter) and,to discuss the formula of time response correction and its application.Methods In the condition of continuous exposure of X-ray machine,the ambient dose equivalent rates shown by survey meters were recorded.In order to get the circuits time constant,the least squares fittingmethod was used to fit the data using the time response formula of circuit having a capacitance C and a resistance R in series.Results The relative uncertainty of fitted circuit time constants was higher than 20％ except for 6150AD6 + 6150AD-b dose meter.The relative uncertainty of fitted r was 8％ for 6150AD6 + 6150AD-b dose meter.Conclusions The time required to stabilize the dosimeter readings was 8,5,3 and 2 s,respectively,for the 451P ionization chamber dosimeter,6150AD6 +6150AD-b dose meter,FH40G + FHZ672E-10 dose meter and AT1123 dose meter.The rising trend of their measured values was not fully accordance with the RC circuit time response correction formula.