Objective To investigate the influencing factors of learning adaptability of nursing student in the emergency department and come up with relevant countermeasures. Methods Two hundred nursing student in the emergency department participated in the survey. A self-designed questionnaire on their learning adaptability and the results were analyzed. Result The job category, work environment, disease of the patients, internship time, teaching method and the professional identification were the top six factors influencing their learning adaptability situation. Conclusion Such measures as strengthening the orientation of student nurses, cultivating their observation ability and communication skills, enhancing the consciousness about law, increasing practice time appropriately, improving teaching methods and ability, and strengthening sense of identity can guarantee effective internship and adaptability of the nursing student in emergency department.

ve To study the effects of extremely low frequency electromagnetic fields (ELF EMFs) on lipid peroxidation of myocardium in rats. Methods The activities of superoxide dismutase (SOD) and the contents of malonaldehyde (MDA) of the myocardium tissue of rats under the different conditions such as healthy state, my-ocardiac ischemic state and lead-exposure state before and after ELF EMFs exposure were determined respectively. Results ELF EMFs exposure didn't induce significant changes of SOD activities and MDA contents in myocardium of healthy rats, but caused the SOD activities of myocardium of lead-exposure rats to decrease from (31.24?1.08)U/mg prot before exposure to ELF EMFs to (29.20?1.14) U/mg prot after exposure to ELF EMFs (P

Objective　In view of the fact that asbestos is not only a key occupational hazard, but also an important environmental pollutant, it is necessary to develop a proper method to decrease the carcinogenecity of asbestos fibers. This study was designed to determine if the surface modification of chrysotile asbestos fiber (CAF) with rare earth compounds (REC) can ameliorate CAF-induced DNA damages in human embryo lung (HEL) cells. Methods　After incubation with REC solution at different concentrations at room temperature for 1 h, natural and REC-pretreated CAF was added to cell culture at various doses. At the selected time as the experiment designed, DNA damages of the HEL cells were detected by Unscheduled DNA Synthesis (UDS) and Single Cell Gel Electrophoresis (SCGE) assays. Results　The UDS induced by natural CAF was elevated with the increase of CAF doses. There was a good dose-response relationship between the UDS and the amount of CAF in the medium and the coefficient of correlation (R) was 0.958 at P<0.05. In REC-pretreated CAF groups, the UDS declined with the increase of REC doses. Both catalase (CAT) and dimethylsulfoxide (DMSO) also reduced the CAF-induced enhancement of UDS. In SCGE assay, CAF induced DNA chain breakage and the magnitude of DNA chain breakage increased in a dose-dependent manner and the coefficient of correlation (R) was 0.992 at p<0.01, while REC-pretreated CAF significantly decreased the induction of DNA chain breakage in a dose-dependent manner(r=0.989, p<0.05). Conclusion　It can be concluded that CAF-induced DNA damages in HEL cells may be partly mediated by oxygen derivatives, and the surface modification of CAF with REC might hide critical sites on the fiber surface, thereby reducing the fiber-mediated production of oxygen derivation and lowering the CAF-induced UDS and DNA chain breakage in HEL cells.

OBJECTIVETo study the effects of extremely low frequency electromagnetic fields (ELF EMFs) on apoptosis and cell cycle of mouse brain and liver cells.

METHODSMice were exposed to 50 Hz, 0.2 mT or 6.0 mT electromagnetic fields for 2 weeks. TUNEL and flow cytometric methods were used to analyze apoptosis and cell cycle of brain and liver cells.

RESULTSAfter exposure to 0.2 mT and 6.0 mT ELF EMFs for 2 weeks, apoptosis rates of brain cells [(5.60 +/- 1.47)% and (4.73 +/- 0.48)% respectively] were higher than that of control [(2.90 +/- 0.75)%], and apoptosis rates of liver cells [(4.19 +/- 2.08)% and (3.38 +/- 0.65)% respectively] were higher than that of control [(1.84 +/- 0.76)%]. G0/G1 cell percentage of brain cells [(80.21 +/- 1.68)% and (79.54 +/- 0.56)% respectively] were higher than that of control [(76.85 +/- 0.83)%], and those of liver cells [(79.42 +/- 1.80)% and (80.47 +/- 1.79)% respectively] were higher than that of control [(73.36 +/- 3.10)%]. The above differences were all statistically significant as P < 0.05. At the same time S and G2 + M cell percentage of brain and liver cells were significantly decreased.

CONCLUSIONExposure to 50 Hz EMFs may alter cell cycle and induce apoptosis of mouse brain and liver cells.

Animals ; Apoptosis ; radiation effects ; Brain ; cytology ; radiation effects ; Cell Cycle ; radiation effects ; Electromagnetic Fields ; Flow Cytometry ; In Situ Nick-End Labeling ; Liver ; cytology ; radiation effects ; Male ; Mice

OBJECTIVETo study the effects of extremely low frequency electromagnetic fields (ELF EMFs) on c-fos gene expression in mouse brain and liver tissues.

METHODSMice were exposed to 50 Hz sinusoidal 0.2 mT or 6.0 mT electromagnetic field for 2 weeks or 4 weeks. Competitive RT-PCR method was used to measure c-fos mRNA level.

RESULTSAfter exposure to 0.2 mT or 6.0 mT field for 2 weeks, c-fos mRNA levels in brain tissue [(0.0178 +/- 0.0076) amol/120 ng cDNA and (0.0092 +/- 0.0042) amol/120 ng cDNA respectively] were higher than that of control level [(0.0012 +/- 0.0005) amol/120 ng cDNA] (P < 0.05). In liver tissue c-fos mRNA levels [(0.0117 +/- 0.0055) amol/120 ng cDNA and (0.0148 +/- 0.0162) amol/120 ng cDNA respectively] were also higher than that of control level [(0.0005 +/- 0.0005) amol/120 ng cDNA] (P < 0.05). After exposure to 0.2 mT or 6.0 mT field for 4 weeks, c-fos mRNA levels in brain tissue [(0.0100 +/- 0.0054) amol/120 ng cDNA and (0.0198 +/- 0.0079) amol/120 ng cDNA respectively] were higher than that of control level [(0.0015 +/- 0.0008) amol/120 ng cDNA] (P < 0.05). In liver tissue the exposure induced much higher expression level [(0.0173 +/- 0.0122) amol/120 ng cDNA and (0.0133 +/- 0.0090) amol/120 ng cDNA respectively] while no expression was found in the control.

CONCLUSIONExposure to 50 Hz electromagnetic fields may induce up-regulation of c-fos transcription in mouse brain and liver tissue.

Animals ; Brain ; metabolism ; radiation effects ; Dose-Response Relationship, Radiation ; Electromagnetic Fields ; Gene Expression Regulation ; radiation effects ; Genes, fos ; genetics ; Liver ; metabolism ; radiation effects ; Male ; Mice ; RNA, Messenger ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Time Factors

OBJECTIVETo study the effects of 50 Hz electromagnetic fields (EMFs) on DNA of testicular cells and sperm chromatin structure in mice.

METHODSMice were exposed to 50 Hz, 0.2 mT or 6.4 mT electromagnetic fields for 4 weeks. DNA strand breakage in testicular cells was detected by single-cell gel electrophoresis assay. Sperm chromatin structure was analyzed by sperm chromatin structure assay with flow cytometry.

RESULTSAfter 50 Hz, 0.2 mT or 6.4 mT EMFs exposure, the percentage of cells with DNA migration in total testicular cells increased from the control level of 25.64% to 37.83% and 39.38% respectively. The relative length of comet tail and the percentage of DNA in comet tail respectively increased from the control levels of 13.06% +/- 12.38% and 1.52% +/- 3.25% to 17.86% +/- 14.60% and 2.32% +/- 4.26% after 0.2 mT exposure and to 17.88% +/- 13.71% and 2.35% +/- 3.87% after 6.4 mT exposure (P < 0.05). Exposure to EMFs had not induced significant changes in S.D.alphaT and XalphaT, but COMPalphaT (cells outside the main population of alpha t), the percentage of sperms with abnormal chromatin structure, increased in the two exposed groups.

CONCLUSION50 Hz EMFs may have the potential to induce DNA strand breakage in testicular cells and sperm chromatin condensation in mice.

Animals ; Chromatin ; radiation effects ; ultrastructure ; Comet Assay ; DNA ; analysis ; radiation effects ; DNA Damage ; Electromagnetic Fields ; Flow Cytometry ; Male ; Mice ; Mice, Inbred Strains ; Spermatozoa ; radiation effects ; ultrastructure ; Testis ; cytology ; radiation effects

OBJECTIVETo prepare monoclonal antibodies (mAbs) against enoyl-CoA hydratase 1 (ECH1).

METHODSNormal human liver tissues were homogenized, and the mitochondria were isolated by differential centrifugation. The total mitochondrial proteins were used to immunize BALB/c mice to prepare mAbs by routine hybridoma technique. The mAbs were characterized by ELISA, Western blotting and immunohistochemistry. The specificity of the antibody was identified by mass spectrometry (MS) following immunoprecipitation (IP) and confirmed by Uni-ZAP expression library screening.

RESULTSOne clone of the hybridoma BGB095 secreting specific mAb against ECH1 was obtained. The mAb was identified to belong to Ig subclass IgG1 and could be used in ELISA, Western blotting, immunohistochemistry, and immunoprecipitation.

CONCLUSIONA hybridoma cell line stably secreting specific mAb against ECH1 has been established. The specific mAb against ECH1 can be of great value for functional and distribution studies of ECH1.

Animals ; Antibodies, Monoclonal ; analysis ; immunology ; Antibody Specificity ; Blotting, Western ; Cell Line ; Enoyl-CoA Hydratase ; immunology ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunohistochemistry ; Liver ; cytology ; metabolism ; Mice ; Mice, Inbred BALB C ; Mitochondria ; metabolism

OBJECTIVETo investigate the effects of extremely low frequency electromagnetic fields (ELF EMFs) on male reproduction in mice.

METHODS94 adult male mice were exposed to 50 Hz sinusoidal electromagnetic fields of 0.2, 3.2 or 6.4 mT for 2 weeks or 4 weeks. Testicular histology and weight, sperm amount, sperm motility and morphology were measured. The percentages of different ploidy cells and cell phases, and DNA content of testis cells were estimated by flow cytometry. The micronucleus rate of bone-marrow cell was also observed.

RESULTSThe testicular weight of the mice exposed to 6.4 mT for 4 weeks [(76.06 +/- 32.25) mg] was significantly lower than that of the control [(111.44 +/- 19.99) mg, P < 0.05]; no significant histopathological changes were observed on the testis in EMFs exposed mice;the sperm amount was decreased after EMFs exposure for 4 weeks, and those of the mice exposed to 0.2 mT and 6.4 mT for 4 weeks [(4.87 +/- 0.94) x 10(6)/ml and (4.30 +/- 1.89) x 10(6)/ml respectively] were significantly lower than that of the control [(6.67 +/- 0.70) x 10(6)/ml, P < 0.05]; the rates of sperm motility also showed a decline. After 0.2, 3.2 or 6.4 mT EMFs exposure for 2 weeks, the deformity rates of sperm [(7.416 +/- 3.352)%, (6.862 +/- 2.947)% and (8.112 +/- 4.615)% respectively] were significantly higher than that of the control [(4.098 +/- 2.028)%, P < 0.01]. Similarly, those of the mice exposed for 4 weeks [(10.267 +/- 3.836)%, (11.027 +/- 7.059)%, (8.814 +/- 3.678)% respectively] were higher than that of the control [(3.714 +/- 1.830)%]. After 6.4 mT exposure for 2 weeks, the percentages of 1C testis cells [(69.56 +/- 4.07)%] was significantly lower than that of the control [(73.45 +/- 3.10)%, P < 0.05]. There were not any remarkable changes in those of 2C, 4C cells. DNA content in different ploidy cells of the mice exposed to 6.4 mT was decreased. Moreover, the cell percentage in S phase was increased significantly (P < 0.01).

CONCLUSIONELF EMFs exposure may have some adverse effects on reproduction in mice.

Animals ; DNA ; metabolism ; Electromagnetic Fields ; Male ; Mice ; Random Allocation ; Reproduction ; radiation effects ; Sperm Count ; Sperm Motility ; radiation effects ; Spermatozoa ; cytology ; metabolism ; radiation effects ; Testis ; cytology ; radiation effects

OBJECTIVETo study the antitumor and distant bystander effects of cationic liposome-mediated cytosine deaminase (CD)/5-fluorocytosine (5-FC) suicide gene system combined with interferon-gamma (IFN-gamma) in vivo.

METHODSMurine hepatoma 22 (H22) cells transfected by CD gene were inoculated subcutaneous in Kunming mice in the left axillary region, and the H22 cells without CD gene transfection were inoculated in the right axillary region. The mice were randomly divided into 4 groups and treated with normal saline , 5-FC, IFN-gamma, and 5-FC+ IFN-gamma on a daily basis. The tumor inhibition and distant bystander effects were observed in the mice.

RESULTSExposure of CD gene-transfected tumor to 5-Fc resulted in obvious tumor growth inhibition with an inhibition rate of 78.38%, which was significantly increased to 93.21% (P<0.01) with 5-Fc +IFN-gamma treatment. A notable distant bystander effect in the CD/5-FC suicide gene system was observed in vivo, with a tumor inhibition rate of was 54.42%; when combined with IFN-gamma, the inhibition rate increased significantly to 87.57% (P<0.05).

CONCLUSIONWhen combined with IFN-gamma, CD/5-FC suicide system has stronger anti-tumor and distant bystander effects. CD/5-FC suicide gene system combined with IFN-gamma may provide a potential therapy for malignant tumors.

Animals ; Bystander Effect ; Cations ; chemistry ; Cytosine Deaminase ; genetics ; Flucytosine ; pharmacology ; Genes, Transgenic, Suicide ; genetics ; Genetic Therapy ; methods ; Interferon-gamma ; therapeutic use ; Liposomes ; Liver Neoplasms, Experimental ; therapy ; Male ; Mice ; Random Allocation

Vascular endothelial growth factor-D (VEGF-D) and vascular endothelial growth factor receptor-2, -3 (VEGFR-2, -3) with their corresponding signaling pathway play significant roles in the development of the embryonic vascular system and pathological lymphangiogenesis. The study was aimed to express and purify the GST-VEGF-D fusion protein, and to explore the angiogenesis effect of VEGF-D. The total RNA was extracted from human fetal lung tissue, and the mature form of VEGF-D was expanded by polymerase chain reaction (PCR), then the plasmid pGEX-5X-1/VEGF-D was reconstructed and the GST-VEGF-D fusion protein expressed in transformed E.coli BL21-DE3. The results showed that the molecular mass of this fusion protein was 38 kD and compassed more than 15% of the total bacteria proteins. The fusion protein was recognized by anti-GST and anti-VEGF-D antibodies. The soluble GST-VEGF-D fusion protein could interact with VEGFR-3/Fc and was able to stimulate the proliferation of human erythroleukemia cell line (HEL) cells. The data of chick embryo chorioallantoic membrane (CAM) experiments indicated that GST-VEGF-D could induce the CAM angiogenesis. It is concluded that the GST-VEGF-D fusion protein with biological activity was successfully expressed, and which may provide an experimental model for the investigation of the VEGF-D-induced angiogenesis and lymphangiogenesis.
Animals ; Chick Embryo ; Chorioallantoic Membrane ; blood supply ; Humans ; Neovascularization, Physiologic ; drug effects ; Recombinant Proteins ; biosynthesis ; genetics ; pharmacology ; Vascular Endothelial Growth Factor D ; biosynthesis ; genetics ; pharmacology