Objective To analyze the drug resistance characteristics,molecular typing,and biological properties of carbapenem-resist-ant Klebsiella pneumoniae(CRKP).Methods A retrospective analysis was conducted on 31 non-repetitive CRKP strains collected clinically from April 2019 to May 2021 at the Third People's Hospital of Nantong.The Vitek 2 Compact microbial analysis system was used for bacterial identification and in vitro drug susceptibility analysis.The broth dilution method was used to determine the minimum inhibitory concentration(MIC)of polymyxin B.The disk diffusion testing was performed to supplement the susceptibility of five com-monly used antibiotics:ertapenem,cefotaxime,cefoxitin,cefoperazone-sulbactam,and tigecycline.The carbapenemase-resistance phenotype of CRKP strains was initially determined by a combined assay of modified carbapenem inactivation method(mCIM)and ED-TA-carbapenem inactivation method(eCIM).Certain carbapenemase resistance genes(blaKPC,blaNDM,blaIMP,blaVIM,and blaOXA-48),AmpC enzyme genes(blaDHA,bla ACC,blaCIT,blaEBC,blaMOX,and blaFOX),extended-spectrum β-lactamases(ESBLs)genes(blaSHv,blaTEM,and blaCTX-M),and nine virulence genes were amplified by PCR and subsequently verified by sequencing.The stringing test was used to screen for hypermucoviscous phenotype strains.The growth curves in vitro and biofilm formation assays,and multilocus se-quence typing(MLST)were performed on 31 isolates.Outer-membrane proteins were extracted and separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)to evaluate the expressions of OmpK35 and OmpK36.Results All the 31 isolates were resistant to ampicillin/sulbactam,ampicillin,aztreonam,cefazolin,ceftriaxone,cefotaxime,cefuroxime,ciprofloxacin,pip-eracillin,piperacillin/tazobactam,meropenem,and ertapenem with resistance rate of 100％.The resistance to polymyxin B was ob-served in 32.26％,whereas tigecycline retained 100％susceptibility.In terms of MLST,three sequence types(STs)were identified,with ST15 being the most prevalent,accounting for 61.29％(19/31)of the isolates.All strains produced serine carbapenemase,and only blaKPC-2 was detected among carbapenem resistance genes.The virulence genes fimH and entB were present in all strains(100％,31/31),while the detection rate of mrkD was 80.64％(25/31).Some strains carried virulence genes such as rmpA,rmpA2,and other virulence genes,whereas magA gene was not detected in any isolate.The carriage rates of rmpA2,iutA,and mrkD were higher in ST11 strains than in ST15 strains.The string test was positive in 38.71％of the strains.The growth test showed that there was no significant difference observed in the growth curves among all strains in vitro,and all were able to form biofilms with varying degrees.All ST11 strains exhibited OmpK36 protein alterations,while OmpK35 protein was intact in the 31 strains.Conclusion CRKP strains in this hospital showed high drug-resistance rate,and ST15 was the predominant sequence type.All the isolates carried blaKPC-2 and virulence genes.Enhanced molecular surveillance and strengthened prevention and control measures of CRKP infection are urgently needed.

Objective To analyze the drug resistance characteristics,molecular typing,and biological properties of carbapenem-resist-ant Klebsiella pneumoniae(CRKP).Methods A retrospective analysis was conducted on 31 non-repetitive CRKP strains collected clinically from April 2019 to May 2021 at the Third People's Hospital of Nantong.The Vitek 2 Compact microbial analysis system was used for bacterial identification and in vitro drug susceptibility analysis.The broth dilution method was used to determine the minimum inhibitory concentration(MIC)of polymyxin B.The disk diffusion testing was performed to supplement the susceptibility of five com-monly used antibiotics:ertapenem,cefotaxime,cefoxitin,cefoperazone-sulbactam,and tigecycline.The carbapenemase-resistance phenotype of CRKP strains was initially determined by a combined assay of modified carbapenem inactivation method(mCIM)and ED-TA-carbapenem inactivation method(eCIM).Certain carbapenemase resistance genes(blaKPC,blaNDM,blaIMP,blaVIM,and blaOXA-48),AmpC enzyme genes(blaDHA,bla ACC,blaCIT,blaEBC,blaMOX,and blaFOX),extended-spectrum β-lactamases(ESBLs)genes(blaSHv,blaTEM,and blaCTX-M),and nine virulence genes were amplified by PCR and subsequently verified by sequencing.The stringing test was used to screen for hypermucoviscous phenotype strains.The growth curves in vitro and biofilm formation assays,and multilocus se-quence typing(MLST)were performed on 31 isolates.Outer-membrane proteins were extracted and separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)to evaluate the expressions of OmpK35 and OmpK36.Results All the 31 isolates were resistant to ampicillin/sulbactam,ampicillin,aztreonam,cefazolin,ceftriaxone,cefotaxime,cefuroxime,ciprofloxacin,pip-eracillin,piperacillin/tazobactam,meropenem,and ertapenem with resistance rate of 100％.The resistance to polymyxin B was ob-served in 32.26％,whereas tigecycline retained 100％susceptibility.In terms of MLST,three sequence types(STs)were identified,with ST15 being the most prevalent,accounting for 61.29％(19/31)of the isolates.All strains produced serine carbapenemase,and only blaKPC-2 was detected among carbapenem resistance genes.The virulence genes fimH and entB were present in all strains(100％,31/31),while the detection rate of mrkD was 80.64％(25/31).Some strains carried virulence genes such as rmpA,rmpA2,and other virulence genes,whereas magA gene was not detected in any isolate.The carriage rates of rmpA2,iutA,and mrkD were higher in ST11 strains than in ST15 strains.The string test was positive in 38.71％of the strains.The growth test showed that there was no significant difference observed in the growth curves among all strains in vitro,and all were able to form biofilms with varying degrees.All ST11 strains exhibited OmpK36 protein alterations,while OmpK35 protein was intact in the 31 strains.Conclusion CRKP strains in this hospital showed high drug-resistance rate,and ST15 was the predominant sequence type.All the isolates carried blaKPC-2 and virulence genes.Enhanced molecular surveillance and strengthened prevention and control measures of CRKP infection are urgently needed.

Objective:To explore the association between the use of tetracyclines during pregnancy and congenital malformations, with the aim of providing evidence-based guidance for the rational use of antibiotics during pregnancy.Methods:Data from the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) and the Canada Vigilance Adverse Reaction (CVAR) database from January 2015 to September 2024 were collected. Five methods including Tree-based scan statistic (TreeScan), proportional reporting ratio (PRR), reporting odds ratio (ROR), the UK Medicines and Healthcare Products Regulatory Agency (MHRA) comprehensive standard, and the Bayesian confidence propagation neural network (BCPNN) were used to detect signals of risk for congenital malformations in offspring following maternal use of tetracyclines during pregnancy. A signal that met the threshold criteria of all above 5 methods was considered as a risk signal. Based on population-based cohort of the drug exposures and adverse pregnancy outcomes (DEEP) data from January 2013 to December 2021 in Xiamen City, propensity score matching (PSM)-based Poisson regression was applied to evaluate the association between the first-trimester tetracyclines exposure and congenital malformations in offspring. Adjusted relative risk (a RR) and its 95% confidence interval ( CI) were calculated. Sensitivity analysis was conducted to validate the reliability of the results. Results:A total of 304 098 reports of adverse events during pregnancy were obtained from the FAERS and CVAR databases. Among them, 5 028 reports were related to tetracyclines, including 1 026 reports of congenital malformations in offspring, involving congenital malformations of musculoskeletal system, other digestive system, and other congenital malformations. Signal detection results suggested that tetracyclines may be a risk signal for above congenital malformations in offspring. The DEEP data included 411 936 pregnant women. After PSM, 240 pregnant women exposed to tetracyclines were included. The results showed no significant association between the first-trimester tetracyclines exposure and congenital malformations in offspring (a RR=0.75, 95% CI: 0.26-2.17), sensitivity analysis also showed no correlation. Conclusions:Data mining from the FAERS and CVAR databases suggests a potential association between tetracyclines use during pregnancy and congenital malformations in offspring. However, the DEEP data study shows no significant correlation.

Objective:To explore the association between the use of tetracyclines during pregnancy and congenital malformations, with the aim of providing evidence-based guidance for the rational use of antibiotics during pregnancy.Methods:Data from the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) and the Canada Vigilance Adverse Reaction (CVAR) database from January 2015 to September 2024 were collected. Five methods including Tree-based scan statistic (TreeScan), proportional reporting ratio (PRR), reporting odds ratio (ROR), the UK Medicines and Healthcare Products Regulatory Agency (MHRA) comprehensive standard, and the Bayesian confidence propagation neural network (BCPNN) were used to detect signals of risk for congenital malformations in offspring following maternal use of tetracyclines during pregnancy. A signal that met the threshold criteria of all above 5 methods was considered as a risk signal. Based on population-based cohort of the drug exposures and adverse pregnancy outcomes (DEEP) data from January 2013 to December 2021 in Xiamen City, propensity score matching (PSM)-based Poisson regression was applied to evaluate the association between the first-trimester tetracyclines exposure and congenital malformations in offspring. Adjusted relative risk (a RR) and its 95% confidence interval ( CI) were calculated. Sensitivity analysis was conducted to validate the reliability of the results. Results:A total of 304 098 reports of adverse events during pregnancy were obtained from the FAERS and CVAR databases. Among them, 5 028 reports were related to tetracyclines, including 1 026 reports of congenital malformations in offspring, involving congenital malformations of musculoskeletal system, other digestive system, and other congenital malformations. Signal detection results suggested that tetracyclines may be a risk signal for above congenital malformations in offspring. The DEEP data included 411 936 pregnant women. After PSM, 240 pregnant women exposed to tetracyclines were included. The results showed no significant association between the first-trimester tetracyclines exposure and congenital malformations in offspring (a RR=0.75, 95% CI: 0.26-2.17), sensitivity analysis also showed no correlation. Conclusions:Data mining from the FAERS and CVAR databases suggests a potential association between tetracyclines use during pregnancy and congenital malformations in offspring. However, the DEEP data study shows no significant correlation.

In order to develop a positive quality control products for the detection of porcine repro-ductive and respiratory syndrome virus(PRRSV)nucleic acid by real-time fluorescent quantitative PCR(RT-qPCR),the positive quality control products of PRRSV-1 and PRRSV-2 M genes were prepared using armored RNA technology of MS2 phage.PRRSV-1 and PRRSV-2 M genes were amplified,purified and recovered,and ligated into pET28b vector containing MS2 mature enzyme protein gene and capsid protein.After transformed into BL21(DE3),the gene products were in-duced by IPTG and purified by PEG6000 precipitation method to prepare the armored RNA virus-like particles(AR-PRRSV)containing PRRSV M gene.Following the performance evaluation,as the positive quality control products of PRRSV-1 and PRRSV-2 M genes,AR-PRRSV1M and AR-PRRSV2M were calculated using YY/T 1652-2019 standard.Results showed that it had a good u-niformity,stable storage for the armored virus-like particles at-20,4,25 ℃ for 60 d,and 37 ℃ for 30 d.The prepared armored virus-like particles AR-PRRSV1M and AR-PRRSV2M were deter-mined by digital quantitative PCR(ddPCR)after preliminary quantification by RT-qPCR.The 104 copies/μL of AR-PRRSV1M and AR-PRRSV2M ddPCR fixation was(1.33+0.50)× 104 cop-ies/μL.The above results indicates that the AR-PRRSVM can be used as the quality control of the whole detection process(nucleic acid extraction,reverse transcription and RT-qPCR).

Objective:To investigate the distribution of intraocular pressure (IOP) in high-altitude population aged 18 years and over in Xining, Qinghai and establish the reference interval (RI) of IOP.Methods:A cross-sectional study was conducted in Xining, Qinghai Province at 2.271 km above sea level from September 2019 to May 2020.Ophthalmic examinations and IOP measurement were conducted among subjects from Physical Examination Center of Qinghai Provincial People's Hospital.The subjects who had been living in Xining without leaving for three months were enrolled.Ophthalmic examinations included vision examination, IOP measurement, slit-lamp microscopy, fundus photography, anterior and posterior segment optical coherence tomography.IOP was measured using Goldmann applanation tonometry under local anesthesia.Subjects with factors that could cause significant changes in IOP and affect the accuracy of IOP measurement, and those who were unable to receive IOP measurement were excluded.Subjects were grouped according to sex, age and ethnicity, and the distribution and RI of IOP were compared among all groups.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Beijing Tongren Hospital, Capital Medical University (No.TRECKY2017-024). Written informed consent was obtained from each subject.Results:A total of 6 120 subjects (6 120 eyes) aged 18-90 years old were enrolled, including 2 850 males and 3 270 females with average age of (45.54±13.85) years.The average IOP of high-altitude population in Xining, Qinghai Province was (14.32±1.93) mmHg (1 mmHg=0.133 kPa), with the RI of 10.54-18.10 mmHg.The average IOP was (14.42±1.98) mmHg in male with the RI of 10.54-18.30 mmHg, (14.23±1.88) mmHg in female with the RI of 10.55-17.91 mmHg.The IOP of male was higher than that of female ( t=3.71, P<0.001). The IOP of Han, Tibetan, Hui and other nationalities were (14.38±1.91), (13.93±2.06), (14.21±1.87), (13.94±1.95) mmHg, respectively, with a statistically significant overall difference ( F=6.73, P<0.001). The IOP of Han nationality was significantly higher than that of Tibetan, Hui and other nationalities, and the differences were statistically significant (all at P<0.05). Conclusions:RI of IOP in high-altitude population from Xining, Qinghai is lower compared with normal altitude area.

Vibrio parahaemolyticus, the main pathogen causing seafood related food poisoning worldwide, has strong biofilm formation ability. ToxR is a membrane binding regulatory protein, which has regulatory effect on biofilm formation of V. parahaemolyticus, but the specific mechanism has not been reported. c-di-GMP is an important second messenger in bacteria and is involved in regulating a variety of bacterial behaviors including biofilm formation. In this study, we investigated the regulation of ToxR on c-di-GMP metabolism in V. parahaemolyticus. Intracellular c-di-GMP in the wild type (WT) and toxR mutant (ΔtoxR) strains were extracted by ultrasonication, and the concentrations of c-di-GMP were then determined by enzyme linked immunosorbent assay (ELISA). Three c-di-GMP metabolism-related genes scrA, scrG and vpa0198 were selected as the target genes. Quantitative real-time PCR (q-PCR) was employed to calculate the transcriptional variation of each target gene between WT and ΔtoxR strains. The regulatory DNA region of each target gene was cloned into the pHR309 plasmid harboring a promoterless lacZ gene. The recombinant plasmid was subsequently transferred into WT and ΔtoxR strains to detect the β-galactosidase activity in the cellular extracts. The recombinant lacZ plasmid containing each of the target gene was also transferred into E. coli 100λpir strain harboring the pBAD33 plasmid or the recombinant pBAD33-toxR to test whether ToxR could regulate the expression of the target gene in a heterologous host. The regulatory DNA region of each target gene was amplified by PCR, and the over-expressed His-ToxR was purified. The electrophoretic mobility shift assay (EMSA) was applied to verify whether His-ToxR directly bound to the target promoter region. ELISA results showed that the intracellular c-di-GMP level significantly enhanced in ΔtoxR strain relative to that in WT strain, suggesting that ToxR inhibited the production of c-di-GMP in V. parahaemolyticus. qPCR results showed that the mRNA levels of scrA, scrG and vpa0198 significantly increased in ΔtoxR strain relative to those in WT strain, suggesting that ToxR repressed the transcription of scrA, scrG and vpa0198. lacZ fusion assay showed that ToxR was able to repress the promoter activities of scrA, scrG and vpa0198 in both V. parahaemolyticus and E. coli 100λpir. EMSA results showed that His-ToxR was able to bind to the regulatory DNA regions of scrA and scrG, but not to the regulatory DNA region of vpa0198. In conclusion, ToxR inhibited the production of c-di-GMP in V. parahaemolyticus via directly regulating the transcription of enzyme genes associated with c-di-GMP metabolism, which would be beneficial for V. parahaemolyticus to precisely control bacterial behaviors including biofilm formation.
Vibrio parahaemolyticus/metabolism* ; Escherichia coli/metabolism* ; Bacterial Proteins/metabolism* ; Transcription Factors/genetics* ; Gene Expression Regulation, Bacterial

Objective:To study the transcriptional regulation of pilABCD by the master quorum sensing (QS) regulator OpaR in Vibrio parahaemolyticus. Methods:Total RNAs were extracted from the wild type (WT) and opaR mutant (Δ opaR) strain. Quantitative real-time PCR (qPCR) was employed to calculate the transcriptional variation of pilA (the first gene of pilABCD operon) between WT and Δ opaR. The regulatory DNA region of pilABCD was cloned into the corresponding restriction endonuclease sites of pHRP309 harboring a promoterless lacZ reporter gene. The recombinant pHRP309 plasmid was then transferred into WT and Δ opaR, respectively, to detect the β-galactosidase activity in cellular extracts using a β-Galactosidase Enzyme Assay System (Promega). The primer extension assay was applied to map the transcription start site of pilABCD using the total RNAs extracted from the WT strain as the template. The regulatory DNA region of pilABCD was amplified by PCR, and the over-expressed His-OpaR was purified under native conditions with nickel loaded HiTrap Chelating Sepharose columns (Amersham). Thereafter, the electrophoretic mobility shift assay (EMSA) was applied to analyze the DNA-binding activity of His-OpaR to the target DNA in vitro, and the DNase I footprinting assay was further employed to detect the DNA-binding sites of His-OpaR within the target DNA. Results:The results of qPCR and LacZ fusion assays showed that OpaR activated the transcription of pilABCD, leading to a gradual increase in the expression level of pilA with the extension of culture time. The primer extension assay detected only one transcription start site located at 155 bp upstream of pilA. The results of EMSA and DNase Ⅰ footprinting assays showed that His-OpaR protected two DNA regions located from -246 to -197 bp and -181 to -131 bp upstream of pilA. Conclusions:Vibrio parahaemolyticus OpaR activated the transcription of pilABCD in a direct manner.

[摘 要] 目的：探讨表皮生长因子受体（epidermal growth factor receptor，EGFR）基因突变与非小细胞肺癌（non-small cell lung cancer，NSCLC）伴脑转移患者预后的相关性，为改善NSCLC合并脑转移患者预后、指导个体化治疗提供临床依据。方法：回顾性分析福建省立医院2013年1月1日至2018年9月30日期间收治的88例NSCLC合并脑转移患者的临床资料，随访取得患者的死亡时间，随访截止日期为2019年10月31日。收集和分析的临床资料包括性别、年龄、吸烟史、病理类型、基因检测、治疗情况、无进展生存期（progression free survival，PFS）、总生存期（overall survival，OS）等。运用生存分析（Kaplan-Meier生存时间曲线）评价EGFR突变型患者的预后，以单因素分析（log-rank检验）预测影响EGFR-TKI治疗效果的因素。结果：88例NSCLC脑转移患者有57例为EGFR突变型，其中位PFS（MPFS）为13.0个月（95%CI：11.951~14.049），明显高于EGFR野生型患者（P=0.003），患者中位生存期（median survival time，MST）为29.0个月（95%CI：20.531~37.468），明显高于EGFR野生型（P=0.001）。EGFR突变型中，Exon19-del突变组患者较Exon21 L858R突变组患者OS有延长趋势（P=0.05），Exon19-del+Exon20T790M突变组患者OS较Exon21 L858R突变组有延长趋势（P=0.077）。结论：EGFR突变组较野生型组NSCLC脑转移患者预后相对好些，且携带19外显子单一缺失突变的患者预后最好。

Objective To generate various types of diabetic retinopathy ( DR) fundus images automatically by computer vision algorithm. Methods A method based on deep learning to generate fundus images was proposed,which used the vascular vein of the fundus image and the text description of lesions as the constraint conditions to generate fundus image. The text description was encoded by using a long short-term memory ( LSTM) , and the vascular vein image was encoded by a convolutional neural network (CNN). Then the encoded information was combined and used to generate a fundus image by generative adversarial networks ( GAN ) . Results The results showed that the algorithm can generate realistic fundus images. However, the image detail features were not obvious because the text-encoded recurrent neural network ( RNN ) loss function did not converge well. Conclusions Using the GAN can generate realistic DR fundus images, which has certain application value in expanding medical data. However,the generation of detail features in small areas still needs improvement.