Antibiotic resistance characteristic and genes analysis of a marine water sourced Klebsiella pneumoniae

Objective:Both antibiotic resistant bacteria (ARBs) and antibiotic resistant genes (ARGs) are considered as one of the most dangerous environmental pollutants in the 21st century by the WHO. This study aims to understand the ARGs of Klebsiella pneumoniae (K. pneumoniae) with multiple drug resistance bacterium from the marine water collected from a beach at Sanya Bay, and to explore the antibiotic resistance mechanism of the K. pneumoniae, providing a basis for exploring the transfer of drug resistance genes of beach, and preventing and controlling the health risk of entertainment population.Methods:The sample of marine water were collected and screened by Mcconkey plate. The drug sensitive test was detected by Merieux VITEK2, The DNA was extracted and one strain of 16srDNA was sequenced and identified as K. pneumoniae. Whole-genome resequencing was performed using Illumina HiseqXten platform, and the obtained sequences were compared with NCBI blasting. The reference bacterium were multi-resistant K. pneumoniae HS11286. Plasmids were extracted and the resistant genes were identified.Results:The ARGs encoding protein was 117/4801 (identity > 40%) and the carrying rate was 2.436 9%. The identity of following ARGs of OKPB, sul1, rpoB, ef-tu, phoP, sul2, AAC(6’)-ib-cr, QnrB, floR, aadA16 were more than 99%. The strain showed resistance to ampicillin, ticacillin/clavulanic acid and chloramphenicol, and was intermediate to ampicillin/sulbactam, compound sulfamethoxazole, ciprofloxacin, minocycline. Preliminary positioning showed that Qnrs, sul1, tetA, cat, QacE were carried on plasmid.Conclusion:The multiple drug resistant bacteria strain has a variety of different resistant phenotypes, some ARGs can be easily spread by plasmid. It probably will bring exposure risk to people for entertainment. Sensibility of some antibiotics were on the brink of resistance, It is necessary to tracking corresponding antibiotics pollution and strengthening monitoring of ARBs and mobile resistant elements of bacteria.

Correlation between quality of drinking water sources and meteorological factors in 2013-2017, Haikou, South China

Objective:With the increasing attention to health influence by ecology environment and climate changes, it is important to explore the characters of drinking water quality and meteorological factors at tropical areas of South China. This study aims to study the water quality of municipal source water and to elucidate the relationship between water quality changes and climatic factors at Haikou.Methods:By analyzing the data of water quality indexes of source water in the past five years from July 2013 to April 2017, the representative indexes as following were analyzed: Fecal coliforms (FC), ammonia nitrogen (NH4Results:Only the CODConclusion:The source water has a higher concentration of iron. The temperature is an important factor that affects the local source water quality of Haikou. It is necessary to strengthen removing COD

Polymorphisms in XPB and XPG subcomplexes of TFIIH is associated with lung cancer risk in a Chinese population: A case-control study

Objective:The transcription factor IIH (TFIIH) helicases XPB and XPD are responsible for opening the DNA strand around the lesion site and endonuclease XPG cleaves the damaged DNA strand on the 3’ side during nucleotide excision repair (NER). Polymorphisms in these three genes that affect DNA repair capacity may contribute to susceptibility of lung cancer. In this study, our objective is to conduct a case-control study of 100 Chinese patients with lung cancer and 100 cancer-free age and sex matched controls to analyse associations between these SNPs and lung cancer susceptibility.Methods:In this hospital-based case-control study, we genotyped 7 SNPs of XPB, XPD and XPG using matrix assisted laser desorption ionisation-time of flight mass spectrometry method (MALDI-TOF) to explore the association with lung cancer risk. To estimate the relative risk of lung cancer associated with SNP genotype, odds ratios (OR) and 95.0% confidence intervals (95.0% CI) were obtained from unconditional multinomial logistic regression models without and with adjustment for potential confounders including age, gender, cigarette smoking and alcohol consumption.Results:The results showed that individuals carrying XPB rs4150434 GA or AA genotype (OR per GA genotype, 1.997; 95.0% CI: 1.031-3.871; P=0.039; OR per AA genotype, 2.435; 95.0% CI: 1.037-5.718; P=0.037), and this association was also find in nondrinkers (OR per GA genotype, 2.477; 95.0% CI: 1.128-5.440; P=0.022). Individuals carrying XPG rs2094258 AA genotype had an increased risk of lung cancer (OR per AA genotype, 3.020; 95.0% CI: 1.015-8.980; P=0.040) compared with individuals with the GG genotype, especially in nondrinkers (OR per AA genotype, 4.020; 95.0% CI: 1.211-13.339; P=0.017). In addition, we found that XPG rs17655 CG or GG genotype associated with decreased lung cancer risk in drinkers (OR per XPG rs17655 CG genotype, 0.238; 95.0% CI: 0.061~0.925; P=0.034; OR per XPG rs17655 GG genotype, 0.l39; 95.0% CI: 0.021-0.938; P=0.032). Haplotype analysis of all 7 SNPs was also conducted. We found that the haplotype of XPB (rs4150441, G>A; rs4150434, G>A) GA and the haplotype of XPG (rs2094258, G>A; rs4771436, T>G; rs17655, C>G) ATC had an increased association with lung cancer.Conclusions:These findings suggest an important role of XPB rs4150434 and XPG rs17655 polymorphisms for a biomarker for lung cancer risk among the Chinese population.

Carriage of drug resistance genes and homology of carbapenem-resistant Acinetobacter baumannii isolated from respiratory intensive care unit / 中国感染控制杂志

Objective To investigate drug resistance genes and epidemic characteristics of β-lactamase carried by carbapenem-resistant Acinetobacter baumannii (CRAB) in the respiratory intensive care unit(RICU) in a hospital.Methods Clinically isolated CRAB from RICU patients in October-December 2015 were collected.Five drug resistance genes (KPC-2,IMP,VIM,NDM-1,OXA-23) were specifically amplified by polymerase chain reaction (PCR),amplified products were performed agarose gel electrophoresis and sequencing analysis,the homology was analyzed with pulsed-field gel electrophoresis (PFGE).Results A total of 22 CRAB strains were isolated in October-December 2015,19 (86.36％) of which were isolated from sputum.The resistance rate of 22 CRAB strains to compound sulfamethoxazole was 59.09 ％,resistance rate to minocycline was 9.09 ％,all were sensitive to polymyxin B,resistance rates to other antimicrobial agents were more than 80％.Three kinds of resistance genes KPC-2,IMP and NDM-1 were not found by PCR amplification,positive rates of VIM and OXA-23 were both 100％.PFGE homology analysis revealed that 22 strains were divided into 13 different types,each type contained 1-5 strains,9 types(69.23％) contained only 1 strain respectively,the other 4 types (30.77％) contained 2-5 strains.A5,A7,and A8;A9,A11,A14,A19 and A22;A4,A10 and A12;A16 and A18 were of the same type respectively.Conclusion The main types of β-lactamase-resistant genes of CRAB in RICU are VIM and OXA-23.Homology analysis shows a small parts are of the same clone strains,which reveals epidemic of a small scale.

Screening and characterization of a bioflocculant produced by Aeromonas sp / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To isolate the bioflocculant-producing bacteria from activated sludge and investigate the flocculating characteristics of the newly isolated bioflocculant.</p><p><b>METHODS</b>Bacteria were screened from activated sludge samples to isolate bioflocculant-producing bacteria. Flocculating activity was used as a measure of the flocculating capability of the bioflocculant.</p><p><b>RESULTS</b>A novel bioflocculant-producing bacterium was isolated, which was identified to belong to genus Aeromonas and named as Aeromonas sp. N11. Flocculating activity increased in the presence of K+, Na+, or Ca2+. The highest flocculating activities for kaolin suspension were obtained in acidic pH ranges, and optimum pHs for it were 3.0, 4.0, and 5.0 with 1 mmol/L K+, Ca+, and Na+ present, respectively. The highest flocculating activities for soil suspension were observed at pH 8.0. The bioflocculant had a good flocculating activity and could achieve a flocculating activity of 92.4% for kaolin suspension at a dosage of only 1 mgxL(-1), and its activity in kaolin suspension was decreased by only 9.2% after heating at 100 degrees C for 60 min.</p><p><b>CONCLUSION</b>The bioflocculant produced by Aeromonas sp. N11 has strong flocculating activity and high stability, which affords high possibility of its practical use.</p>

Assessment of a Bathing Beach Environment and Human Health Effect / 环境与健康杂志

Objective To investigate the environmental quality and water quality of bathing beach in Haikou,Hainan province and the effects on human health.Methods The investigation of the bathing beach environment and the water quality were conducted according to Bathing Beach Monitoring Regulations(2002).The water samples were collected at PM 3:00-5.00 on May 28th to June 3th in 2007 from three sampling sites,No.1(easily be polluted),No.2(crowded),No.3(less pollution).The questionnaire survey was conducted on the present day and 7 days later,the items included the respiratory,digestive systems infection and eye,ear,nose and skin inflammation,the survey was completed in two days.Results The environment survey of bathing beach suggested that non-point source pollution caused by domestic wastewater emerged on raining days,the salinity was 31‰-33‰,clarity exceeded 30 centimeter and no heat pollution was found.The pH value,chroma,dissolved oxygen,nitrate nitrogen,chemical oxygen demand,inorganic nitrogen,fecal coli group was 8.01-8.10,11.42-15.00 NTU,5.60-6.71 mg/L,0.16- 0.17mg/L,2.70-3.40mg/L,0.19-0.21 mg/L and 35.0-36.0/L respectively.Four hundred and eight questionnaires were eligible, the response rate was over 90%.The results demonstrated that the swimmers were facing to the increased illness risk from the water quality,such as skin pruritus,gastrointestinal allergies,throat sore,eye and ear and nose infections.There was distinct higher proportion in the participants with water contact and complained one or more symptoms than those without water contact(P