Objective To quantitatively investigate the effect of low-dose ionizing radiation on the frequencies of chromosome aberrations and micronucleus-containing cells of radiation workers.Methods Nine electronic databases were systematically searched on the basis of the published studies evaluating the effects of low-dose ionizing radiation on the frequencies of chromosome aberrations and micronucleuscontaining cells.Of the 195 studies searched,21 studies were identified with a total of 1 970 626 cells under studying.Cochrane' s Q and I2 statistics were used to evaluate heterogeneity among studies and pooling odds ratio (OR) with 95％ confidence intervals (CI) were calculated using random-effect models or fixed-effect models,and publication bias were also calculated.Meta-analysis was performed using Stata 12.0.Results The pooling OR of chromosome-type aberrations [OR =3.03 (2.59,3.56)],dicentric plus centric rings [OR =4.12 (2.99,5.67)],translocations [OR =2.73 (1.67,4.46)],micronucleuscontaining cells [OR =1.70 (1.40-2.06)] were higher for radiation workers when compared with control group.Conclusions The frequencies of chromosome aberrations and micronucleus cell of peripheral lymphocytes are significantly high in radiation workers who were occupationally exposed to low-dose ionizing radiation.It should be noted that the radiation protection of radiological workers be enhanced.

Objective To quantitatively analyze the effects of high background radiation area (HBRA) on the frequencies of translocation and unstable chromosome aberrations in human peripheral blood lymphocytes.Methods Based on the data from 9 published articles retrieved from 7 electronic databases,the Meta-analysis was performed to evaluate the effects of high natural background radiation (HNBR) on the frequencies of chromosome aberrations in the peripheral blood lymphocytes in 17 777 persons from HBRA and 10 386 from the control area (CA).Cochrane's Q and I2 statistics were used to evaluate heterogeneity among studies and pooling odds ratio (OR) with 95％ confidence intervals (95％ CI) were calculated using random-effect models.Publication bias was also calculated by funnel plot,Egger linear regression test and Begg rank correlation test.Results The pooling OR of translocation [OR(95％ CI) =1.57(1.10-2.24)] and unstable chromosome aberration [OR(95％ CI) =2.04(1.32-3.14)] of long-term exposed inhabitants living in HBRA were higher than control.The subgroup analysis showed that,fortranslocation,the OR (95％ CI) were 1.24 (1.09-1.42,I2 =0.00) for male,1.37 (1.17-1.60,I2 =0.00) for female,1.17 (1.05-1.30,I2 =69.50％) for adults,and 1.38 (1.25-1.51,I2 =0.00) for Chinese.For unstable chromosome aberration,the OR (95％ CI) were 3.78 (2.40-5.97,I2 =0.00) for female,2.60 (2.25-3.00,I2 =69.60％) for adults,1.03(0.85-1.24,I2 =0.00) for children,3.19 (2.46-4.13,I2 =21.60％) for Iranian,and 1.64 (1.33-2.02,I2 =0.00) for Chinese.HBRA,age and sex differences were the reasons of above heterogeneity.Conclusions To the inhabitants living in HBRA,the frequencies of translocation and unstable chromosome aberration of peripheral blood lymphocytes are higher than those in control area.More comprehensive analysis should be performed to assess the health risk in HBRA inhabitants,which may arise new stragety in radiation protection.

BACKGROUNDAtrial AutoCapture™ (ACap™) was a new technological development that confirmed atrial capture by analyzing evoked response (ER) with a new method - paced depolarization integral ER detection - and optimized energy output to changes in the stimulation threshold. The purpose of this study was to evaluate the clinical performance of ACap™ function.

METHODSThis was a prospective, observational, nonrandomized two-center study. Between November 2008 and August 2014, 102 patients were enrolled from two different institutions. Data were collected by case report forms at enrollment, hospital discharge, and in-office follow-ups scheduled at 1, 2, 3, 6, and 12 months postimplantation.

RESULTSAmbulatory ACap™ function started to become available for 20.6% of patients at 1 day, then progressed to 30.4% at 7 days, 38.6% at 1 month, 41.6% at 2 months, 47.5% at 3 months, 53.5% at 6 months, and 63.4% at 1 year. The cause of the unsuccessful attempts to perform ACap™ threshold was ER/polarization <2:1. Availability for SD, BND, and HOCM indications had shown better results than AVB indication. For SD indication cases, feasibility was significantly better for SD with paroxysmal atrial fibrillation (pAF) than SD without pAF (78.4% vs. 35.0% at 1 year, n = 71, P< 0.001). At each stage of the clinical follow-ups, there had been a strict correlation between ACap™ measurements and those conducted manually with P 0.001 (n = 299).

CONCLUSIONSIt has been concluded that ACap™ function was safe and effective to confirm atrial threshold and reduce energy output automatically. ACap™ function is unavailable for some patients at early stages of the implantation; however, availability has been progressively increasing during follow-up.

OBJECTIVETo investigate genetic and antibiotic resistance characteristics of Campylobacter jejuni (C. jejuni) isolated from Shenzhen.

METHODSMultilocs sequence typing and agar dilution methods were used to define the genotype and antibiotic resistance of C. jejuni, respectively.

RESULTSIn total, 126 C. jejuni strains were isolated. The prevalence of C. jejuni was 5.3% in diarrheal patients. The prevalence in poultry meat (36.5%) was higher than that in cattle meat (1.1%). However, the prevalence in poultry cloacal swabs (27.0%) was lower than that in cattle stool (57.3%). Sixty-two sequence types were obtained, among which 27 of the STs and 10 alleles were previously unreported. The most frequently observed clonal complexes were ST 21 (11.9%), ST-22 (10.3%), and ST-403 (7.1%). ST-21, ST-45, ST-354, ST-403, and ST-443 complexes overlapped between isolates from patients and cattle, whereas ST-45 and ST-574 complexes overlapped between isolates from patients and poultry. All C. jejuni were resistant to at least one antibiotic. The highest resistance rate was toward ciprofloxacin (89.7%), followed by tetracycline (74.6%), and nalidixic acid (69.0%).

CONCLUSIONThis is the first report of the genotypes and antibiotic resistance of C. jejuni in Shenzhen. Overlapping clonal complexes were found between isolates from patients and cattle, and between patients and poultry.