Electromagnetic Fields ; adverse effects ; Humans ; Mutagenicity Tests

Objective To investigate whether smoking affects metabolism and methylation of arsenic. Methods Six papers about the relation between smoking and arsenic metabolism, methylation were collected until December,2008, and the data were quantitatively analyzed with random and fixed effect models. Results In the group of smoking, the summary weighted mean difference of percent of inorganic in urinary was 0.59 (95% CI:-0.01-1.18). The summary weighted mean difference of percent of MMA in urinary was 2.44 (95%CI:1.95-2.94). The summary weighted mean difference of percent of DMA in urinary was -3.04 (95%CI:-4.01- -2.07). Current evidence suggested that percent of MMA was higher, percent of DMA was lower in smoking or ever smoking group compared with nonsmoking group. Conclusion Smoking may be considered a risk factor for metabolism and methylation of arsenic on human.

Objective To clone human cell division cycle gene 2(CDC2)from human liver cancer tissue and express CDC2 protein in E.coli BL-21(DE3).Methods The total RNA was extracted from liver cancer tissue and amplified by reverse transcription polymerase chain reaction(RT-PCR).The PCR products were cloned into the prokaryotic expression vector pET28a(+)followed by DNA sequencing.The recombinant pET28a(+)/CDC2(rCDC2)plasmid was transformed into E.coli.The rCDC2 was induced with IPTG and characterized by SDS-PAGE.Results The cloned CDC2 gene was composed of 894 nucleotides,and is accordance with that reported in GenBank.The prokaryotic expression vector was constructed successfully.The CDC2 protein was successfully expressed in E.coli.Conclusion The CDC2 cDNA is successfully cloned from human liver cancer tissue,and can express in E.coli.

Objective: To discuss the procedure and clinical effect of retroperitoneal laparoscopic nephropexy (RLN).Methods: From August 2001 to June 2006, RLN was performed on 28 female patients aged 26-45 years old (mean, 34±2.5) with symptomatic nephroptosis, including 15 with the right kidney, 12 with the left, and 1 with both. The preoperative complaint of patients included subjective symptoms (constant and recurring pain in 28 patients) and objective symptoms (upper urinary infections in 16, hematuria in 12, and upper tract obstruction in 12). One patient underwent nephropexy via the transperitoneal approach and the others underwent nephropexy via the retroperitoneal approach. A retroperitoneoscopic procedure was performed after positioning the patients in the flank position. Digital preparation of the retroperitoneal space was made and standardized trocar was placed. The key step of the surgery was complete exposure of the kidney within Gerota' fascia, which was aimed to separate the potential adhesions between the colon and kidney or between the inferior blood vessels of the kidney. Nephropexy was performed between the fibrous capsule at the lower pole of the kidney and the dissected psoas muscle, using three sutures placed by intracorporeal technique or the percutaneous needle both for introduction and removal of the suture; the sutures were separately tied over the sacrospinalis fascia. Results: The mean operative time was (125±9) min (ranging 115-240 min); the mean postoperative hospital stay was (9±1.2) days, largely owing to the required 5-12 days' bed rest. During a mean follow-up of (24±4.2) months(ranging 3 to 70 months), 3 patients had paresthesia, 5 had constant and recurrent ache, 20 were completely free of pain, and 4 had micro-hematuria. One patient had further episodes of pyelonephritis and upper tract obstruction after operation. Intravenous pyelogram(IVP) revealed that the ptosis incorporated into more than one vertebral body in 2 patients. Postoperative renal function test showed an improvement in renal function. Conclusion: RLN is mini-invasive and has less complication. The procedure should be considered as one of the optimal therapy for nephroptosis.

Objective To investigate the value of combined use of laparoscopic cholecystectomy(LC)and duodenoscopic procedures in the treatment of gallbladder stones with common bile duct stones.Methods We retrospectively analyzed clinical data of 164 cases of gallbladder stones with common bile duct stones treated with laparoscopic cholecystectomy + endoscopic sphincterotomy(EST)from January 2003 to December 2007.Results All the cases underwent ERCP and endoscopic sphincterotomy(EST)followed by LC.In the 164 cases,196 bile duct stones were extracted from 155cases with a success rate of 94.5%.The procedures were unsuccessful in 9 cases,and among them,4 cases had stricture of bile duct more than 2 cm in length,and 5 cases had impacted stones that precluded passage of the guide wire.After EST,6 of the 155 cases had the complication of mild acute pancreatitis and LC was performed after its treatment.The success rate of LC was 96.5% and the average hospital stay was(11?4)d.Conclusions The combined use of EST and ERCP before LC is effective in treatment of gallbladder stones with common bile duct stones,and has broadened the utilization of minimally invasive treatment for bile duct diseases.

Objective:To explore the improvement effect of tirofiban on the myocardial reperfusion of non-ST segmant elevated myocardial infarction (NSTEMI) patients underwent percutaneous coronary intervention (PCI) treatment.Methods:78 NSTEMI patients underwent PCI in our hospital from April 2012 to April 2015 were selected and divided into the observation group (n=38) and the control group (n=40) according to different drugs.Patients in the control group were given asprin,clopidogrel and heparin,while patients in the observation group were additionally given tirofiban.Then the myocardial contrast echocardiography (MCE) was taken to evluate the myocardial reperfusion.Results:No statistical difference was found in the levels of A,β,A β,CK-MB and cTnⅠ before PCI between 2 groups.The levels of β,A β of observation group were obviously higher,CK-MB and cTnⅠ were obviously lower than those of the control group(P＜0.05).The MACE rate of observation group was 2.63％,which was 5.00％ in the control group,no significant difference was between two groups (P＞0.05).Conclusion:Tirofiban could obviously improve the myocardial reperfusion of NSTEMI patients underwent PCI with high safety.

Objective To investigate the change in antimicrobial susceptibility of Enterococcus faecalis (E.faecalis) and Enterococcus faecium (E.faecium) isolated from clinical urine specimens, so as to provide laboratory evidence for clinical anti-infective treatment.Methods Antimicrobial susceptibility of E.faecalis and E.faecium isolated from urine specimens from 20 tertiary hosptials in China between 2004 and 2014 were analyzed, drug-resistant genes of vancomycin-resistant Enterococcus(VRE)were detected with polymerase chain reaction (PCR).Results A total of 788 Enterococcus strains were isolated in 2004-2014, 371 strains were E.faecalis strains, 417 were E.faecium strains.Susceptibility rates of E.faecalis to ampicillin, nitrofurantoin, fosfomycin, vancomycin, and teicoplanin were all>90%, susceptibility rates to rifampin, minocycline, and erythromycin were all<20%, there was significant difference in the susceptibility rate of E.faecalis to fosfomycin betwen July 2011-June 2012 and July 2009-June 2010(P<0.0167).Susceptibility rates of E.faecium to vancomycin and teicoplanin were 96.9% and 97.4% respectively, susceptibility rates to nitrofurantoin, minocycline, and fosfomycin were 41.7%, 51.8%, and 78.2% respectively, susceptibility rates to ampicillin, levofloxacin, rifampicin, and erythromycin were all<10%;susceptibility rates of E.faecium to nitrofurantoin had decreased tendency in different years (any two group comparison, all P<0.0167), susceptibility rates to fosfomycin in July 2011-June 2012 and July 2013-June 2014 both decreased compared with July 2009-June 2010(both P<0.0167),there were no significant changes in antimicrobial usceptibility rates in different years.14 strains of VRE all carried vanA resistance gene.Conclusion E.faecalis strains isolated from urine are susceptible to ampicillin, nitrofurantoin, and fosfomycin, E.faecium are not susceptible to most antimicrobial agents;E.faecalis and E.faecium are both susceptible to vancomycin and teicoplanin, only a few strains are resistant to antimicrobial agents.

Objective To decrease radiation induced toxicities especially mucostis in patients with locally advanced nasopharyngeal carcinoma( NPC ) who underwent concurrent radiochemotherapy, the maximum tolerated dose and dose limited toxicities of capecitabine combination with cisplatin were observed. Methods From Aug 2006 to Oct 2007, 24 patients with intensity modulated radiotherapy(IMRT) and concurrent chemotherapy with capecitabine and cisplatin for nasopharyngeal carcinoma(stages Ⅲ-Ⅳ) were enrolled in this study. There were four dose-level groups of Capecitabine[625-1250 mg/(m2 ·d) , d1-14]and fixed cisplatin dose[20 mg/(m ·d) ,d1-5) ]MRI and CT scan were used for evaluation of tumor shrinkage. Treatment related toxicities were evaluated according to the common toxicity criteria( NCI-CTC Version 3.0). Results The acute side-effects include Grade 3 or Grade 4 mucosal toxicity(lasting for at least 5 d) and Grade 3 or Grade 4 non-mucosal toxicity were evaluated. Group 625 mg/m2 and Group 825 mg/m2 had none, Group 1000 mg/m2 had 6 patients and Group 1250 mg/m2 had 3 patients for mucosal toxicity, which were the main dose-limited toxicity and relevant to the dose of capecitabine apparently( P < 0. 05 ). There was also a trend of increase by the dose level of capecitabine for other toxicities. The median follow-up time for all patients was 28. 5 months. The locoregional recurrence occurred in 2 patients and distant metastasis in 2 patients. Two-year overall survival rate and locoregional control rate were 100% and 91.7%, respectively.Complete response and partialresponse were found on MRI or CT scan in patients of 29. 2% at the end of treatment and 83. 3% after three months, respectively. Conclusions The combination regimen of capecitabine and cisplatin is safe and effective according to the preliminary result. Toxicities related to radiochemotherapy for NPC were significantly associated with the dose level of chemotherapy.

Objective: To investigate the level of arsenic exposure in rural drinking water and to assess the health risk caused by exposure to arsenic in Tongzhou District, Beijing Municipality in 2019, so as to provide insights into improving the quality of rural drinking water. Methods: Water samples were collected from self-provided wells in 196 villages of 7 townships in Tongzhou District from April to June, 2019, and the arsenic levels were measured in drinking water according to Standard examination methods for drinking water-Metal parameters (GB/T 5750.6-2006). The carcinogenic and non-carcinogenic risks of arsenic were evaluated in drinking water using the environmental risk assessment model recommended by the United States Environmental Protection Agency (EPA). Results: Totally 520 water samples were collected, and the median arsenic concentration was 0.001 2-0.050 0 mg/L. There were 67 water samples with arsenic levels exceeding the defined standard level (12.88%), and the proportions of arsenic levels exceeding the defined standard level were 57.69%, 17.24%, 12.20%, 6.52% and 1.31% in Songzhuang, Huoxian, Lucheng, Zhangjiawan and Yongdedian townships, and the arsenic levels did not exceed the defined standard level in Majuqiao or Taihu townships. The carcinogenic risk of arsenic was 3.135 7×10-4/a in drinking water, which exceeded the maximum acceptable risk, and the carcinogenic risk of arsenic all exceeded the maximum acceptable risk, with the highest value seen in Songzhuang Township (9.648 2×10-4/a). A high carcinogenic risk of arsenic was seen in men at ages of 60 to 80 years (3.012 8×10-4/a) and in women at ages of 80 years and older (2.949 0×10-4/a). The non-carcinogenic risk of arsenic was 0.696 8 in drinking water, indicating a low risk, and were 1.009 5 and 2.144 1 in Huoxian and Songzhuang townships, indicating a high risk. In addition, a high non-carcinogenic risk of arsenic was seen in men at ages of 60 to 80 years (0.669 5) and in women at ages of 80 years and older (0.655 3). Conclusion There was a high proportion of arsenic levels exceeding the defined standard level in rural drinking water in Tongzhou District, 2019, and there was a health risk, notably with the highest carcinogenic risk seen in residents at ages of 60 years and older. Effective interventions are needed to reduce arsenic levels in drinking water.

Objective To investigate the effects of target-controlled infusion (TCI)of dexme-detomidine on the median effective concentration of effect-site (Ce50 )of propofol at loss of conscious-ness (LOC)in patients.Methods Sixty-four patients,28 males and 36 females,aged 20-60 years, ASA physical status Ⅰ or Ⅱ,scheduled for elective surgery,were randomly allocated to receive dexmedetomidine of 0 ng/ml (group P),dexmedetomidine of 0.4 ng/ml (group D1),dexmedetomi-dine of 0.6 ng/ml (group D2)and dexmedetomidine of 0.8 ng/ml (group D3)for 1 5 min before TCI of propofol,n =1 6 in each group.The propofol infusion was started to provide an effect-site concen-tration of 1.0 μg/ml,and increased by 0.2 μg/ml when propofol effect-site concentration and target concentration were equilibrium until LOC.Results The Ce50 (95%CI )at loss of consciousness in groups P,D1,D2 and D3 were 2.30 (2.24-2.36)μg/ml,1.92 (1.87-1.96 )μg/ml,1.60 (1.55-1.65)μg/ml and 1.41 (1.35-1.45 )μg/ml,respectively.There was a negative correlation between the effect-site concentration of propofol-induced LOC and target concentration of dexmedetomidine (r=-0.84,P <0.01).Compared with groups P,D1 and D2,the incidence of bradycardia was higher in group D3 (P <0.05).Conclusion The Ce50 of propofol-induced LOC gradually decreases with in-creasing target concentration of dexmedetomidine.Combining propofol with dexmedetomidine of 0.4 or 0.6 ng/ml that can reduce the Ce50 of propofol-induced LOC,which is suitable for induction of an-esthesia with a lower incidence of bradycardia.