基于CiteSpace的国内外经颅直流电刺激研究图谱量化分析

目的 对2012—2022年国内外有关经颅直流电刺激(tDCS)领域研究现状、热点及前沿的文献进行文献计量和可视化分析,为我国tDCS领域的进一步发展和深入研究提供依据。方法检索中国知网(CNKI)和WebofScience核心合集数据库中2012—2022年相关文献,使用CiteSpace6.1.R3绘出可视化网络图,对发文国家、机构、作者分布以及关键词共现、聚类、突现图进行分析。结果共纳入国内文献926篇,国外文献8040篇进行分析。2012—2021年国内外有关tDCS领域研究的发文量逐年递增,并于2017年开始大幅度提升。国内发文量于2018年突破100篇,国外发文量于2021年突破1000篇,达到顶峰。高频关键词为“脑卒中”“抑郁症”“帕金森病”“精神分裂症”“工作记忆”“运动表现”等;关键词突现分析提示近年来研究聚焦于“头针”“脑电图”“头痛”“青少年”等。结论 tDCS对脑卒中及卒中后功能障碍、帕金森病、意识障碍等神经系统疾病的康复,对抑郁症、精神分裂症等精神疾病的治疗,对工作记忆的调控以及在体育方面的应用是目前研究的热点。

Remimazolam benzenesulfonate anesthesia effectiveness in cardiac surgery patients under general anesthesia

BACKGROUND Sedation with propofol injections is associated with a risk of addiction,but remimazolam benzenesulfonate is a comparable anesthetic with a short elimination half-life and independence from cell P450 enzyme metabolism.Compared to remimazolam,remimazolam benzenesulfonate has a faster effect,is more quickly metabolized,produces inactive metabolites and has weak drug interactions.Thus,remimazolam benzenesulfonate has good effectiveness and safety for diagnostic and operational sedation.AIM To investigate the clinical value of remimazolam benzenesulfonate in cardiac surgery patients under general anesthesia.METHODS A total of 80 patients who underwent surgery in the Department of Cardiothoracic Surgery from August 2020 to April 2021 were included in the study.Using a random number table,patients were divided into two anesthesia induction groups of 40 patients each:remimazolam(0.3 mg/kg remimazolam benzenesulfonate)and propofol(1.5 mg/kg propofol).Hemodynamic parameters,inflammatory stress response indices,respiratory function indices,perioperative indices and adverse reactions in the two groups were monitored over time for comparison.RESULTS At pre-anesthesia induction,the remimazolam and propofol groups did not differ regarding heart rate,mean arterial pressure,cardiac index or volume per wave index.After endotracheal intubation and when the sternum was cut off,mean arterial pressure and volume per wave index were significantly higher in the remimazolam group than in the propofol group(P<0.05).After endotracheal intubation,the oxygenation index and the respiratory index did not differ between the groups.After endotracheal intubation and when the sternum was cut off,the oxygenation index values were significantly higher in the remimazolam group than in the propofol group(P<0.05).Serum interleukin-6 and tumor necrosis factor-αlevels 12 h after surgery were significantly higher than before surgery in both groups(P<0.05).The observation indices were re-examined 2 h after surgery,and the epinephrine,cortisol and blood glucose levels were significantly higher in the remimazolam group than in the propofol group(P<0.05).The recovery and extubation times were significantly lower in the remimazolam group than in the propofol group(P<0.05);there were significantly fewer adverse reactions in the remimazolam group(10.00%)than in the propofol group(30.00%;P<0.05).CONCLUSION Compared with propofol,remimazolam benzenesulfonate benefited cardiac surgery patients under general anesthesia by reducing hemodynamic fluctuations.Remimazolam benzenesulfonate influenced the surgical stress response and respiratory function,thereby reducing anesthesia-related adverse reactions.

基于多元线性回归分析和随机森林算法的水稻贮藏霉变风险控制

阐明真菌的生长机理对于减少储粮损失具有重要意义。在影响真菌孢子生长的因素中,最重要的因素是环境温度、稻谷含水量和储藏时间。因此,本研究基于实验数据建立了孢子数和温度、含水率和储藏天数等几个重要因素之间的多元线性回归模型。为了建立更准确的模型,我们将随机森林算法引入稻谷储藏过程中的真菌孢子数目预测模型,用于预测储藏过程中不同温度、含水率和储藏天数下的孢子数。对于随机森林模型,99%的预测值和其对应的原始数据可以达到同一数量级,对于预测孢子数具有很高的准确性。此外,我们绘制了预测曲面图,将环境条件控制在低风险区域可以有效降低稻谷在储藏过程中的霉变风险。

Rapid and reversible Na deposition onto Al nanosheet arrays

Sodium metal battery(SMB)is regarded as a promising candidate for next-generation high-energy battery due to high theoretical capacity and abundant natural resources.However,the growth of sodium dendrites and large volume expansion during the processes of sodium plating and stripping seriously restrict the practical application of SMBs.Here,a three-dimensional skeleton of aluminum nanosheet arrays(Al NSARs)is constructed by a facile etching approach to achieve rapid and reversible Na plating/stripping.The Al NSARs with large geometric specific surface and plentiful cavities can provide rich active nucleation sites,reduce local current density and accommodate Na volume change,which lead to uniform deposition of sodium with dendrite-free morphology.As a result,Na plating/stripping on Al NSARs can stably operate over 650 cycles at 2 mA cm^(-2)/2 mAh cm^(-2)with average Coulombic efficiency(CE)of 100.0%and low potential polarization of 27 mV.Moreover,the full cell of Na_(s)V_(2)(PO_(4))_(3)||Al NSARs@Na can run for over 1800 cycles at a high rate of 20C.These superior properties,combined with relatively low cost and weight of Al,enable our AlNSARs to begreat prospect for practical applications.

Rehabilitation nursing for an earthquake survivor with severe polytrauma:A case report and literature review

The aim of this article is to summarize the experience of rehabilitation nursing of one case of severe polytrauma caused by earthquake.The key points of the rehabilitation nursing include body posture nursing,orthopedic rehabilitation nursing,pulmonary function rehabilitation nursing,bladder rehabilitation nursing,nutritional support,and psychological rehabilitation nursing.Through the comprehensive rehabilitation nursing interventions,satisfactory outcomes were obtained,and the patient was successfully recovered and discharged after 2 months.

A fluorogenic-inhibitor-based probe for profiling and imaging of monoamine oxidase A in live human glioma cells and clinical tissues

Monoamine oxidase A(MAO-A)plays a critical role in the development of glioma and other neurological disorders.Specific analysis of MAO-A activities and its drug interactions in intact tissue is important for biological and pharmacological research,but highly challenging with current chemical tools.Fluorogenic-inhibitor-based probes offer improved selectivity,sensitivity,and effectiveness to image and profile endogenous targets in an activity-based manner from mammalian cells,which are however rare.Herein,we report HD1 as the first fluorogenic-inhibitor-based probe that can selectively label endogenous MAO-A from various mammalian cells and clinical tissues.The probe was delicately designed based on N-propargyl tetrahydropyridine,a small MAO-A-specific fluorogenic and inhibitory war-head,so that the probe becomes fluorescent upon in situ enzymatic oxidation and covalent labeling of MAO-A.With the excellent binding affinity(in vitro K_(i)=285 n M)and fluorogenic properties,HD1 offers a promising approach to simultaneously image endogenous MAO-A activities by super-resolution fluorescence microscopy and study its drug interactions by subsequent activity-based protein profiling,in both live cells and human glioma tissues.

Prediction and determination of mildew grade in grain storage based on FOA-SVM algorithm

Grain mildew is a significant hazard that causes food loss and poses a serious threat to human health when severe.Therefore,effective prediction and determination of mildew grade is essential for the prevention and control of mildew and global food security.In the present study,a model for predicting and determining the mildew grade of rice was constructed using logistic regression,back propagation neural network and GS-SVM(a grid search-based support vector machine algorithm)based on laboratory culture data and actual data from a granary,respectively.The results show that the GS-SVM model has a better prediction effect,but the model cannot automatically adjust the parameters and is more subjective,and the accuracy may decrease when the data set changes.Therefore,this paper establishes a new model for a support vector machine based on a fruit fly optimization algorithm(FOA-SVM),which can achieve automatic parameter search and automatically adjust its parameters to find the best result when the data set changes,with a strong ability of self-adjustment of parameters.In addition,the FOA-SVM converges quickly and the model is stable.The results of this study provide a technical method for early identification of mildew grade during grain storage,which is beneficial for the prevention and control of rice mildew during grain storage.

Safety and immunogenicity of a mosaic vaccine booster against Omicron and other SARS-CoV-2 variants:a randomized phase 2 trial

An ongoing randomized,double-blind,controlled phase 2 trial was conducted to evaluate the safety and immunogenicity of a mosaic-type recombinant vaccine candidate,named NVSI-06-09,as a booster dose in subjects aged 18 years and older from the United Arab Emirates(UAE),who had administered two or three doses of inactivated vaccine BBIBP-CorV at least 6 months prior to enrollment.The participants were randomly assigned with 1:1 to receive a booster dose of NVSI-06-09 or BBIBP-CorV.The primary outcomes were immunogenicity and safety against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variant,and the exploratory outcome was cross-immunogenicity against other circulating strains.Between May 25 and 30,2022,516 adults received booster vaccination with 260 in NVSI-06-09 group and 256 in BBIBP-CorV group.Interim results showed a similar safety profile between two booster groups,with low incidence of adverse reactions of grade 1 or 2.For immunogenicity,by day 14 post-booster,the fold rises in neutralizing antibody geometric mean titers(GMTs)from baseline elicited by NVSI-06-09 were remarkably higher than those by BBIBP-CorV against the prototype strain(19.67 vs 4.47-fold),Omicron BA.1.1(42.35 vs 3.78-fold),BA.2(25.09 vs 2.91-fold),BA.4(22.42 vs 2.69-fold),and BA.5 variants(27.06 vs 4.73-fold).Similarly,the neutralizing GMTs boosted by NVSI-06-09 against Beta and Delta variants were also 6.60-fold and 7.17-fold higher than those by BBIBP-CorV.Our findings indicated that a booster dose of NVSI-06-09 was well-tolerated and elicited broad-spectrum neutralizing responses against divergent SARS-CoV-2 variants,including Omicron and its sub-lineages.

苏北地区规模化猪场产肠毒素大肠杆菌的分离鉴定及灭活疫苗效果评估

[目的]产肠毒素大肠杆菌(Enterotoxigenic Escherichia coli,ETEC)是引起仔猪腹泻的重要病原菌,本研究通过调查苏北地区规模化猪场ETEC的流行情况,分析其生物学特性,研制具有免疫保护效果的优势血清型菌株的灭活疫苗,以期对苏北地区ETEC的防控提供参考。[方法]从苏北地区规模化猪场采集3-30日龄的仔猪新鲜粪样、肛拭子及小肠组织样,分离出ETEC,对分离菌株进行血清型鉴定、耐药性测定、小鼠致病力测定;最后通过动物免疫试验研究优势血清型菌株灭活疫苗对小鼠的免疫保护效果。[结果]从21个规模化猪场采集病料562份,通过PCR鉴定及测序得到141株ETEC;血清凝集试验鉴定出85株菌的O抗原血清型,其中08、0101和0128为优势血清型,占定型菌株的61.2%(52/85),其他血清型包括09、03、020、0148、0149等;分析141株ETEC对14种常见抗生素的耐药情况,得出分离株对新霉素、红霉素、四环素、庆大霉素、强力霉素、阿莫西林、甲氧苄啶/磺胺甲恶唑高度耐药,耐药率均高达80%以上;对恩诺沙星敏感性较高,敏感率达50.4%(71/141);对多粘菌素B和头孢噻肟中介耐药,占比分别为66%(93/141)和51.8%(73/141);多重耐药现象严重,其中10重耐药的菌株占比最大,为19%(27/141);小鼠攻毒试验测得08血清型强毒株YC-6的半数致死量(median lethal dose,LD50)为1.4×10^7 CFU/只,最低致死量(minimum lethal dose,MLD)为3×10^7 CFU/只;08血清型强毒株YC-6和0101血清型强毒株LYG-3制备的单价灭活疫苗对小鼠的保护率均达到100%,因此利用08血清型强毒株YC-6和0101血清型强毒株LYG-3研制二价灭活疫苗,结果显示该二价疫苗对感染不同血清型ETEC小鼠的保护率在83%以上。[结论]本研究通过对苏北地区ETEC的流行病学调查,得出其优势血清型,并研制出针对对优势血清型免疫保护效果较好的二价灭活疫苗,给临床ETEC的监测和防控提供参考。

PagGRF12a interacts with PagGIF1b to regulate secondary xylem development through modulating PagXND1a expression in Populus alba×P.glandulosa

Growth-regulating factors(GRFs)are important regulators of plant development and growth,but their possible roles in xylem development in woody plants remain unclear.Here,we report that Populus alba×Papulus glandulosa PagGRF12a negatively regulates xylem development in poplar.PagGRF12a is expressed in vascular tissues.Compared to non-transgenic control plants,transgenic poplar plants overexpressing PagGRF12a exhibited reduced xylem width and plants with repressed expression of PagGRF12a exhibited increased xylem width.Xylem NAC domain 1(XND1)encodes a NAC domain transcription factor that regulates xylem development and transcriptional analyses revealed that PagXND1a is highly upregulated in PagGRF12a-overexpressing plants and downregulated in PagGRF12a-suppressed plants,indicating that PagGRF12a may regulate xylem development through PagXND1a.Transient transcriptional assays and chromatin immunoprecipitation-polymerase chain reaction assays confirmed that PagGRF12a directly upregulates PagXND1a.In addition,PagGRF12a interacts with the GRF-Interacting Factor(GIF)PagGIF1b,and this interaction enhances the effects of PagGRF12a on PagXND1a.Our results indicate that PagGRF12a inhibits xylem development by upregulating the expression of PagXND1a.

EAEC噬菌体PNJ1809-11和PNJ1809-13作为环境消毒剂的杀菌效果评估

【目的】分析2株肠聚集性大肠杆菌(EAEC)CVCC232噬菌体PNJ1809-11、PNJ1809-13的生物学特性,并对其作为环境消毒剂的杀菌效果进行评估。【方法】透射电镜下观察PNJ1809-11、PNJ1809-13的形态;通过宿主谱、最佳感染复数(MOI)、一步生长曲线、对pH和温度耐受性的测定分析PNJ1809-11、PNJ1809-13的生物学特性;比较2株噬菌体的体外杀菌效果和喷雾、雾化处理后的杀菌效果;检测噬菌体在模拟养殖环境下的耐受性,及喷雾处理的噬菌体制剂在模拟养殖环境下的杀菌效果和对宿主菌生物被膜的清除效果;分析宿主菌的抗性突变率。【结果】电镜下观察PNJ1809-11、PNJ1809-13均为肌尾病毒科噬菌体;PNJ1809-11可裂解155株大肠杆菌,PNJ1809-13可裂解46株大肠杆菌;噬菌体PNJ1809-11、PNJ1809-13的最佳感染复数(MOI)均为10,最适pH均为7;与PNJ1809-13相比,PNJ1809-11具有较好的热稳定性;在模拟的封闭装置中,将两株噬菌体分别经喷雾、雾化处理后,二者对宿主菌的杀灭效果均可达99%以上;对人工污染的粪便表面细菌的杀灭效果均达到99%以上。噬菌体PNJ1809-11、PNJ1809-13及两者的混合制剂(噬菌体鸡尾酒)对宿主菌CVCC232形成的生物被膜的裂解效率分别为78%、30%和83%。噬菌体PNJ1809-11在养殖温度、粪便pH以及阳光照射下,其耐受性均强于PNJ1809-13。宿主菌对PNJ1809-11、PNJ1809-13的抗性突变率分别为2.5×10^(-3)和1.0×10^(-3)。【结论】综上,噬菌体PNJ1809-11的环境耐受力更强,噬菌体鸡尾酒对生物被膜的裂解效果更好,提示噬菌体PNJ1809-13或噬菌体鸡尾酒经喷雾处理后具有作为环境杀菌剂的潜力。

Implementation of a reference-scaled average bioequivalence approach for highly variable generic drug products of agomelatine in Chinese subjects

The aim of this study was to apply the reference-scaled average bioequivalence (RSABE) approach to evaluate the bioequivalence of 2 formulations of agomelatine, and to investigate the pharmacokinetic properties of agomelatine in Chinese healthy male subjects. This was performed in a single-dose, randomized-sequence, open-label, four-way crossover study with a one-day washout period between doses. Healthy Chinese males were randomly assigned to receive 25 mg of either the test or reference formulation. The formulations were considered bioequivalent if 90% confidence intervals (CIs) for the log-transformed ratios and ratio of geometric means (GMR) of AUC and C m of agomelatine were within the predetermined bioequivalence range based on RSABE method. Results showed that both of the 90% CIs for the log-transformed ratios of AUC and C-max of 7-desmethyl-agomelatine and 3-hydroxyagomelatine were within the predetermined bioequivalence range. The 90% CIs for natural log transformed ratios of C-max, AUC(0-t), and AUC(0-infinity) of agomelatine (104.42-139.86, 101.33-123.83 and 97.90-117.94) were within the RSABE acceptance limits, and 3-hydroxy-agomelatine (105.55-123.03, 101.95-109.10 and 101.72-108.70) and 7-desmethyl-agomelatine (104.50-125.23, 102.36-111.50 and 101.62-110.64) were within the FDA bioequivalence definition intervals (0.80-1.25 for AUC and 0.75-1.33 for C-max). The RSABE approach was successful in evaluating the bioequivalence of these two formulations. (C) 2016 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.

Identification of tick-borne pathogen diversity by metagenomic analysis in Haemaphysalis longicornis from Xinyang,China

Background:A wide variety of pathogens could be maintained and transmitted by Haemaphysalis longicornis.The aim of this study is to systematically examine the variety of pathogens carried by Haemaphysalis longicornis,an importnatn vector,in tick-borne diseases epidemic area,and to estimate the risk of human infection imposed by tick bites.Methods:Adult questing ticks were collected in Xinyang,central China.Genomic DNA and RNA were extracted from 144 H.longicornis ticks individually,and sequenced respectively as the templates for high-throughput sequencing.Clean reads were compared against the database of NCBI nucleotide collection and specific PCR was performed to confirm the presence of pathogen.Phylogenetic analysis was performed to explore the evolutionary status of pathogens.Results:The assignment of reads to taxa based on BLASTN results revealed the existence of several potential pathogens,including Anaplasma spp.,Rickettsia spp.,Babesia sp.,as well as severe fever with thrombocytopenia syndrome bunyavirus(SFTSV).Comfirmantory PCR assays revealed the existence of Anaplasma bovis(13/144,9.03%),Anaplasma centrale(2/144,1.39%),Rickettsia heilongjiangensis(3/144,2.08%),Rickettsia sp.LON-13(1/144,0.69%),Rickettsia raoultii(5/144,3.47%),Babesia sp.(1/144,0.69%).SFTSV accounted for the highest detected pathogen with a positive rate of 18.75%(27/144).Three of the ticks(2.08%)were co-infected with SFTSV and A.bovis.Conclusion:Our study provided a broadened list of microorganism that harbored by H.longicornis.In previously unrecognized endemic regions,prokaryotic and eukaryotic infection including Anaplasma spp.,Rickettsiae spp.,and Babesia spp.should be considered,along with the well-known SFTSV for patients with tick bites history.A novel Babesia species was identified in local natural foci,which needs further investigation in the future.

New techniques of on-line biological sample processing and their application in the field of biopharmaceutical analysis

Biological sample pretreatment is an important step in biological sample analysis. Due to the diversity of biological matrices, the analysis of target substances in these samples presents significant challenges to sample processing. To meet these emerging demands on biopharmaceutical analysis, this paper summarizes several new techniques of on-line biological sample processing: solid phase extraction, solid phase micro-extraction, column switching, limited intake filler, molecularly imprinted solid phase extraction, tubular column, and micro-dialysis. We describe new developments, principles, and characteristics of these techniques, and the application of liquid chromatography mass spectrometry (LC MS) in biopharmaceutical analysis with these new techniques in on-line biological sample processing. (C) 2016 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND

Intracellular pharmacokinetic study of zidovudine and its phosphorylated metabolites

Zidovudine (AZT), the first drug approved by the US Food and Drug Administration for the treatment of human immunodeficiency virus (HIV) infection, is metabolized in the host cells to 5'-AZT triphosphate (AZT-TP) which inhibits HIV reverse transcriptase. As the pharmacokinetics of AZT and its phosphorylated metabolites in human peripheral blood mononuclear cells (hPBMCs) is limited, the aim of this study was to determine the pharmacokinetic parameters of AZT and its phosphorylated metabolites in hPBMCs from 12 healthy Chinese male subjects after a single oral dose of 600 mg of AZT. Blood samples were collected prior to drug administration, then at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8 and 10 h after drug administration. Mononuclear cells collected by Ficoll-Hypaque density gradient centrifugation were used for determination of AZT and metabolites [AZT monophosphate (AZT-MP), AZT diphosphate (AZT-DP) and AZT-TP] and the plasma was used to evaluate the pharmacokinetics of AZT. Plasma concentration of AZT peaked within 0.583 h and intracellular concentrations of AZT, AZT-MP, AZT-DP and AZT-TP peaked within 1.083, 1.500, 1.417 and 1.583 h, respectively. AZT in plasma was eliminated rapidly with t(1/2) of 2.022 h, and AZT-MP, AZT-DP and AZT-TP were eliminated with t(1/2) of 13.428, 8.285 and 4.240 h, respectively. The plasma concentration of the phosphorylated metabolites was not quantifiable. (C) 2016 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.

基于大环多胺[12]aneN_(3)多功能非病毒基因载体的合成及性质

基因治疗的提出为人类遗传疾病和重大疾病的治愈带来了重要机遇,经过几十年曲折的发展,基因治疗逐渐得到人们的认可,且相关药品开始进入市场.但与人们的预期相比,基因治疗的发展比较缓慢,一个关键的因素就是缺乏安全高效的基因载体,尤其是非病毒基因载体.在过去十多年,各种各样的非病毒基因载体得到了极大的发展.我们课题组以大环多胺[12]aneN_(3)为正电单元,利用非病毒基因载体的结构可调性,引入单光子、双光子及聚集诱导和近红外荧光显像单元、酯酶和谷胱甘肽刺激响应单元以及胆酸、生物素靶向单元,设计合成了一系列多功能非病毒基因载体,通过凝胶电泳实验、细胞毒性、细胞摄取、细胞器逃逸、定性定量转染实验以及各种荧光成像技术,研究了它们对质粒DNA和siRNA的递送转染性能及其转染过程,发展了一些生物相容性好、基因转染效率高的非病毒基因载体,进一步研究了它们在诊疗一体化、联合治疗等方面的潜力.本文从结构设计与性质研究两个方面介绍了我们在多功能型非病毒基因载体方面的工作进展,概括总结了各种结构的设计与合成,系统总结了基因转染效率提升与机理探究.最后,对非病毒基因载体未来的发展方向进行了展望.

Outbreaks of Acute Respiratory Disease Associated with Human Adenovirus Infection in Closed Camps,China,December 2011–March 2014

Summary What is already known on this topic?Human adenovirus(HAdV)was frequently associated with acute respiratory disease(ARD)outbreaks in military camps.What is added by this report?HAdV-B7,HAdV-B14,and HAdV-B55 were determined to be responsible for 3,2,and 4 ARD outbreaks in military camps,China,respectively,with a total attack rate of 28.0%during 2011 to 2014.

Epigenetic Regulation of a Powdery Mildew Resistance Gene in Medicago truncatula

Dear Editor, Medicago truncatula is a model legume that is conge- neric with alfalfa （Medicago sativa）, a forage crop of global importance. Over the last decade, tremendous genetic and genomic tools have been developed for this model system, which has greatly facilitated the study of various aspects of legume genomics and biology. From an applied perspective, genomic information gained from M. truncatula is particu- larly useful for genetic improvement of cultivated alfalfa, a crop that is not amenable to genetic analysis because of its allogamous and autotetraploid nature （Yang et al., 2008）. For instance, M. truncatula can be used to clone the orthologs of many economically important genes in alfalfa,

UV light tolerance and reactivation potential of tetracycline-resistant bacteria from secondary effluents of a wastewater treatment plant

Tetracycline-resistant bacteria（TRB） are of concern as emerging microbial contaminants in reclaimed water.To understand the effects of UV disinfection on TRB,both inactivation and reactivation profiles of TRB,as well as 16 tetracycline-resistant isolates from secondary effluent,were characterized in this study.The inactivation ratio of TRB was significantly lower（3.0-log） than that of heterotrophic bacteria（〉4.0-log） in the secondary effluent.Additionally,the proportion of TRB significantly increased from 1.65%to 15.51%under20 mJ/cm^2 ultraviolet（UV） exposure.The inactivation rates of tetracycline-resistant isolates ranged from 0.57/s to 1.04/s,of which tetracycline-resistant Enterobacter-1 was the most tolerant to UV light.The reactivation of TRB,tetracycline-resistant isolated strains,as well as heterotrophic bacteria commonly occurred in the secondary effluent even after20 mJ/cm^2 UV exposure.The colony forming ability of TRB and heterotrophic bacteria reached 3.2-log and 3.0-log under 20 mJ/cm^2 UV exposure after 22 hr incubation.The final inactivation ratio of tetracycline-resistant Enterobacter-1 was 1.18-log under 20 mJ/cm^2 UV exposure after 22 hr incubation,which is similar to those of TRB（1.18-log） and heterotrophic bacteria（1.19-log）.The increased proportion of TRB and the reactivation of tetracycline-resistant enterobacteria in reclaimed water could induce a microbial health risk during wastewater reuse.