Accidents, Occupational ; prevention & control ; Occupational Diseases ; prevention & control ; Occupational Health Services ; organization & administration ; Risk Assessment ; methods ; organization & administration

Base Sequence ; Cell Line, Tumor ; Enhancer Elements, Genetic ; genetics ; HT29 Cells ; Humans ; Luciferases ; genetics ; metabolism ; Molecular Sequence Data ; Plasmids ; genetics ; Polymerase Chain Reaction ; Promoter Regions, Genetic ; genetics ; Recombinant Fusion Proteins ; genetics ; metabolism ; Simian virus 40 ; genetics ; Telomerase ; genetics ; Transcription, Genetic ; Transfection

OBJECTIVETo explore the differential proteomic expression in human liver cells L-02 after exposure to HQ.

METHODSSubcultured L-02 cells were treated by HQ for 24 h at a 1 x 10(-4) mol/L concentration and a blank group was set as the control. Immediately after the treatment, total cellular proteins were extracted and separated by 2-DE, and the images were analyzed by PDQuest software. The experiment was totally repeated 3 times with 3 repetitions for each group every time. The well repeated spots were identified by MALDI-TOF MS and then searched in NCBI human protein database with Mascot.

RESULTSAbout 1,000 spots per gel were found. Compared with the control group, 17, 18 and 24 spots were significantly altered in 3 separate experiments. The 4 well repeated spots were identified by MALDI-TOF MS as Rho GDP dissociation inhibitor GDI alpha, 6-phosphogluconolactonase, erbB3 binding protein EBP1 and lamin A/C, isoform 1 precursor. They were involved in cell skeleton, signal transduction and energy metabolization in functional classification.

CONCLUSIONHydroquinone can change the protein expression in liver cells, which provides clues for exploring the toxic mechanism.

Cell Line ; Electrophoresis, Gel, Two-Dimensional ; Hepatocytes ; drug effects ; metabolism ; Humans ; Hydroquinones ; toxicity ; Mass Spectrometry ; Proteomics ; Reproducibility of Results

OBJECTIVETo investigate the changes of gene expression in rat neuron induced by 1.8 GHz radiofrequency electromagnetic fields (RF EMF) to screen for RF EMF-responsive genes and the effect of different exposure times and modes on the gene expression in neuron.

METHODSTotal RNA was extracted immediately and purified from the primary culture of neurons after intermittent exposed or sham-exposed to a frequency of 1.8 GHz RF EMF for 24 hours at an average special absorption rate (SAR) of 2 W/kg. Affymetrix Rat Neurobiology U34 array was applied to investigate the changes of gene expression in rat neuron. Differentially expressed genes (Egr-1, Mbp and Plp) were further confirmed by semi-quantitative revere transcription polymerase chain reaction (RT PCR). The expression levels of Egr-1, Mbp and Plp were observed at different exposure times (6, 24 h) and modes (intermittent and continuous exposure).

RESULTSAmong 1200 candidate genes, 24 up-regulated and 10 down-regulated genes were found by using Affymetrix microarray suite software 5.0 which are associated with multiple cellular functions (cytoskeleton, signal transduction pathway, metabolism, etc.) after functional classification. Under 24 h and 6 h intermittent exposure, Egr-1 and Plp in experiment groups showed statistic significance (P < 0.05) compared with the control groups, while expression of Mbp did not change significantly (P > 0.05). After 24 h continuous exposure, Egr-1 and Mbp in experiment groups showed statistic significance (P < 0.05) compared with the control group, while expression of Plp did not change significantly (P > 0.05). Under the same exposure mode 6 h, expression of all the 3 genes did not change significantly. Different times (6, 24 h) and modes (intermittent and continuous exposure) of exposure exerted remarkable different influences on the expression of Egr-1, Mbp, Plp genes (P < 0.01).

CONCLUSIONThe changes of many genes transcription were involved in the effect of 1.8 GHz RF EMF on rat neurons; Down-regulation of Egr-1 and up-regulation of Mbp, Plp indicated the negative effects of RF EMF on neurons; The effect of RF intermittent exposure on gene expression was more obvious than that of continuous exposure; The effect of 24 h RF exposure (both intermittent and continuous) on gene expression was more obvious than that of 6 h (both intermittent and continuous).

Animals ; Cells, Cultured ; Dose-Response Relationship, Radiation ; Down-Regulation ; radiation effects ; Electromagnetic Fields ; Neurons ; metabolism ; radiation effects ; Rats ; Up-Regulation ; radiation effects

OBJECTIVETo investigate the changes of gene expression in rat neurons induced by 1.8 GHz radiofrequency electromagnetic fields (RF EMF) and to screen for the RF EMF-responsive genes.

METHODSNewly-born SD rats in 24 hours were sacrificed to obtain cortex and hippocampus neurons. The cells were divided randomly into two groups: the experiment group (the irradiation group) and the control group (the false irradiation group). In the irradiation group, after twelve days' culture, neurons were exposed to 1.8 GHz RF EMF modulated by 217 Hz at a specific absorption rate (SAR) of 2 W/kg for 24 hours (5 minutes on/10 minutes off) while in the false control group, the neurons were put in the same waveguide as in the irradiation group, but were not exposed to any irradiation. The total RNA was isolated and purified immediately after exposure. The affymetrix rat neurobiology U34 assay was used for detecting the changes in gene expression profile according to the manufacturer's instruction. RF EMF-responsive candidate gene was confirmed by using ribonuclease protection assay (RPA).

RESULTSAmong 1200 candidate genes, the expression levels of 34 genes were up or down regulated. Microtubule associated protein 2 (Map2) gene was selected as the candidate and subjected to further analysis. RPA data clearly revealed that Map2 was statistically significantly up-regulated after neurons were exposed to the RF EMF (P < 0.05).

CONCLUSIONThe modulation of gene expression and function of Map2 as a neuron specific cytoskeleton protein is crucial to maintain the normal framework and function of neurons. The finding that 1.8 GHz RF EMF exposure increases the expression of Map2 might indicate some unknown effects of RF EMF on neurons.

Animals ; Animals, Newborn ; Cell Phone ; Cells, Cultured ; Dose-Response Relationship, Radiation ; Down-Regulation ; Electromagnetic Fields ; Female ; Gene Expression ; radiation effects ; Male ; Microtubule-Associated Proteins ; biosynthesis ; genetics ; Neurons ; metabolism ; radiation effects ; Radio Waves ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Up-Regulation

OBJECTIVETo investigate the toxic and DNA damaging effect of acrylamide (AA) on human keratinocytes and its mechanism.

METHODS(1) After the keratinocyte cell line HaCaT cells were exposed to AA with different concentrations for 44 hours, cell survival rate was detected by MTT method. (2) The effects of DNA damage of exposed cells were detected by comet assay. (3) After treating the cells with 2.00 mmol/L of AA plus 0.50 mmol/L of 1-aminobenzotriazole (1-ABT), an inhibitor of cytochrome P-450 enzymes (CYP-450), for 4 hours, the relationship between DNA damage and CYP-450 was studied.

RESULTS(1) Cytotoxicity measurement of AA showed that cell survival rate decreased significantly after 44-hour treatment. (2) Cytotoxicity was not detected after 4-hour AA treatment, but significant DNA damage was observed in all treatment groups, and the degree of damage increased with the concentration of AA. Moreover, the tail lengths of comet cells were in dose-effect relationship. As for cells treated by 1-ABT with 2 mmol/L AA, comet rate and tail length were 15.4% and (8.2 +/- 2.0) micro m respectively, which were decreased significantly (P < 0.01) when compared with 2 mmol/L AA treatment group [80.6% and (44.3 +/- 4.0) micro m].

CONCLUSIONSAcrylamide has significant cytotoxicity and genotoxicity on HaCaT cells. AA-induced DNA damage may be related to the oxidative metabolite(s) of AA through CYP-450.

Acrylamide ; toxicity ; Cells, Cultured ; Cytochrome P-450 Enzyme Inhibitors ; DNA Damage ; Dose-Response Relationship, Drug ; Humans ; Keratinocytes ; drug effects ; enzymology

Objective To investigate the changes of gene expression in rat neurons induced by 1.8 GHz radiofrequency electromagnetic fields (RF EMF) and to screen RF EMF-responsive genes. Methods The rat primary cultured neuronal cells were divided into two groups, the radiation group and control group, from which the total RNA was extracted immediately and purified after intermittently (5min on/10min off) exposed or U34 array was applied to detect the changes of gene expression in rat neurons. Results Among 1200 candidate genes, 24 up-regulated and 10 down-regulated genes which are associated with multiple cellular functions (cytoskeleton, signal transduction pathway, metabolism, etc.) after functional classification were found by using Affymetrix microarray suite software 5.0. Although the changes in gene expression were less than 2 folds, they had statistical significance (P<0.01). Conclusion RF radiation of 1.8GHz induce the changes of many genes transcription in rat neurons, some of which indicate the negative effects of RF radiation on neurons.

OBJECTIVETo investigate the role of B7-H1 expression in IL-10 production, the B7-H1 and IL-10 expression levels in pancreatic carcinoma tissues and to analyze the correlation between B7-H1 expression and IL-10 level.

METHODSThe mRNA and protein levels expressions of B7-H1 and IL-10 in 35 cases of pancreatic cancer and corresponding paracarcinoma tissues and 5 cases of normal pancreas tissues were detected by RT-PCR, Western blot and immunohistochemistry respectively.

RESULTSThe findings for the first time provided the evidences that there was a clear trend for B7-H1 and IL-10 expressions to be most highly expressed in carcinoma tissue, intermediately expressed in paracarcinoma tissue, and expressed at the lowest level in normal pancreatic tissue at mRNA and protein levels. Moreover, there were statistically significant differences in B7-H1 and IL-10 expression between pancreatic carcinoma tissues, corresponding paracarcinoma tissues and normal pancreatic tissues at mRNA and protein levels (P < 0.05). Furthermore, the immunohistochemistry indicated that there were high expression levels of B7-H1 (60.5% +/- 12.7%) and IL-10 (65.3% +/- 16.2%) in pancreatic carcinoma tissues while there were no significant expressions in normal pancreatic tissues. Meanwhile, correlation analysis revealed that B7-H1 expression was significant associated with IL-10 level in tumor tissues at mRNA (P = 0.008, r = 0.841) and protein levels (P = 0.007, r = 0.838).

CONCLUSIONSOver-expression of B7-H1 may be responsible for the increasing IL-10 production in pancreatic cancer, which caused reduced immune response to tumor cells and contributed to pancreatic carcinoma escape from immune attack.

Antigens, CD ; immunology ; B7-H1 Antigen ; Humans ; Immune Evasion ; Interleukin-10 ; immunology ; Pancreatic Neoplasms ; immunology

OBJECTIVETo evaluate the efficiency, feasibility and safety of gasless endoscopic thyroid surgery through compared research.

METHODSFrom July 2001 to Oct. 2005, 83 cases that had received gasless endoscopic thyroid surgery were compared with 80 cases that had received conventional surgery and analyzed on operating time, blood loss, cosmetic effects, complications and costs.

RESULTSCompared with conventional thyroid surgery, endoscopic thyroid surgery group had better cosmetic effects. There was only minimal neck wound or even no neck wound. The cost of hospitalization in the endoscopic group was higher than that in the conventional group (10,844 +/- 2373) RMB and (7585 +/- 1081) RMB respectively (t = -7.23, P < 0.001). The endoscopic group had less blood loss than the conventional group (25 +/- 21) ml and (36 +/- 23) ml respectively (t = 3.160, P < 0.01), but had longer operating time (107 +/- 30) min and(79 +/- 19) min respectively (t = -7.225, P < 0.01). However, when the surgeon had got more experiences and applied the advanced harmonic scalpel, the operative time and blood loss reduced obviously.

CONCLUSIONSCompared with conventional thyroid surgery, gasless endoscopic thyroid surgery has the major advantage that it has cosmetic effect and has small or no scar left on neck. It can be concluded that this technique was efficiency, feasibility and safety. It can offer another choice for the thyroid neoplasms patients.

Adult ; Aged ; Endoscopy ; methods ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; Thyroid Diseases ; surgery ; Thyroid Gland ; surgery ; Thyroidectomy ; methods ; Young Adult

OBJECTIVESTo evaluate preliminary clinical experience for combining awake craniotomy and intraoperative language brain mapping within the integrated 3.0 T intraoperative magnetic resonance imaging (iMRI) suite.

METHODSFrom December 2010 to April 2011, 11 right hand-dominant patients with left glioma were involved in, or adjacent to, eloquent cortex was carried out awake craniotomies with cortical stimulation within an integrated 3.0 T iMRI suite. Aphasia battery of Chinese was used to test the language function before the operation. During the procedure, after the occipital, temporal, and supraorbital nerves were blocked by the anesthesiologists, the head was fixed with a custom high-field MRI-compatible head holder. The skull and dura was opened as usual and language brain mapping was then performed. Language testing followed a set protocol: counting numbers from 1 to 50, naming objects, reading single words. Resection of the tumor was guided by neuronavigation system and continued until eloquent areas were encountered or the margin of assessment was reached. An interdissection MRI was acquired to evaluate the glioma removal in a movable MRI scanner after minimal draping. Meanwhile, adverse effects caused by electrical stimulation and iMRI were recorded. The follow-up speech tests were assessed on 7th day and 1 month at least after the operation.

RESULTSThe combined use of 3.0 T iMRI and awake craniotomy was performed safely in all patients. No adverse effects were reported. The duration of surgery was prolonged by 2 to 4 h. The patients' perception of iMRI during surgery was favorable. First-look MRI studies led to further resection attempts in 6/11 cases as well as a 3/11 increase in the number of gross-total resections. One week after surgery, baseline language function worsened in 4 cases. However, no patients had a persistent language deficit one month after surgery.

CONCLUSIONSAwake craniotomy and direct cortical electrical stimulation can be performed safely and effectively within a 3.0 T iMRI suite. The combination of high-field iMRI and awake craniotomy may facilitate safe removal of eloquent glioma.

Adult ; Aged ; Anesthesia ; methods ; Brain Neoplasms ; surgery ; Cerebral Cortex ; surgery ; Craniotomy ; methods ; Female ; Glioma ; surgery ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Monitoring, Intraoperative ; Neuronavigation ; methods ; Wakefulness