Low interleukin-10 level indicates a good prognosis in Salmonella enterica serovar typhimurium-induced pediatric hemophagocytic lymphohistiocytosis:A case report

BACKGROUND Secondary hemophagocytic lymphohistiocytosis(sHLH)triggered by Salmonella enterica serovar Typhimurium is rare in pediatric patients.There is no consensus on how to treat S.typhimurium-triggered sHLH.CASE SUMMARY A 9-year-old boy with intermittent fever for 3 d presented to our hospital with positive results for S.typhimurium,human rhinovirus,and Mycoplasma pneumoniae infections.At the time of admission to our institution,the patient’s T helper 1/T helper 2 cytokine levels were 326 pg/mL for interleukin 6(IL-6),9.1 pg/mL for IL-10,and 246.7 pg/mL for interferon-gamma(IFN-γ),for which the ratio of IL-10 to IFN-γwas 0.04.In this study,the patient received meropenem,linezolid,and cefoperazone/sulbactam in combination with high-dose methylprednisolone therapy(10 mg/kg/d for 3 d)and antishock supportive treatment twice.After careful evaluation,this patient did not receive HLH chemotherapy and recovered well.CONCLUSION S.Typhimurium infection-triggered sHLH patient had a ratio of IL-10 to IFN-γ≤1.33,an IL-10 concentration≤10.0 pg/mL,and/or an IFN-γconcentration≤225 pg/mL at admission.Early antimicrobial and supportive treatment was sufficient,and the HLH-94/2004 protocol was not necessary under these conditions.

Induction of deletion mutation on ompR gene of Salmonella enterica serovar Typhi isolates from asymptomatic typhoid carriers to evolve attenuated strains for vaccine development

Objective:To develop allenualed slrains of Salmonella enterica serorar Typhi(S.typhi) for the candidate vaccine by osmolar stress.Mothods:S.typhi SS3 and SS5 strains were isolated from asymptomatic typhoid carriers in Mamakkal,Tamil Nadu.India.Both strains were grown in LB(Luria Bertani) medium supplemented with various concentration of NaCl(0.1- 0.7M) respectively.The effecl of osmolar stress was determined at molecular level by PCR using MCR 06 and MCR07 primers corresponding to ompR with chromosomal DNA of S.typhi SS3 and SS5 strains.Attenuation by osmolar stress results in deletion mutation of the.S.typhi slrains was determined by agglutination assays,precipitation method.SDS PAGE analysis and by animal models.Results:The 799 bp amplified ompR gene product from wild type S.typhi SS3 and SS5 illustrate the presence of virulent gene.Interestingly,there was only a 282 bp amplified product from S.typhi SS3 and SS5 grown in the presence of 0.5.0.6 and 0.7 M NaCl.This illustrates the occurrence of deletion mutation in ompR gene al high concentration of NaCl.Furthermore,both the wildtype and mutant S.typhi outer membrane SDS-PAGF.profile reveals the differences in the expression of ompF.ompC and ompA proteins.In mice,wild type and mutant strains lethal dose(LD_(50)) were determined.The mice died within 72 h when both the wild type strains were injected intraperitoneally with 3 log CFU-mL^(-1).When the mice were injected with the mutants in same dosage,no clinical symptoms were observed;whereas the serum antibodv litre was elicited within two weeks indicated that the mutants have the ability to induce protective humoral immune response.These results suggest that S.typhi SS3 and SS5 may bo used as good candidate strains for the development of live attenuated vaccine against salmonellosis.Conclusions:This study demonstrates that the S.typhi strains were allenualed and could be good vaccine candidates in future.

THE CONSTRUCTION AND EXPRESSION OF RECOMBINANT SHUTTLE PLASMID WITH OMPL1 GENE FROM LEPTOSPIRA INTERROGANS SEROVAR LAI STRAIN 017 IN BACILLE CALMETTE-GUERIN

Objective.To construct recombinant BCG again st leptospirosis.Methods.We amplified the entire open readin g frame of the OmpL1gene from the genome of the leptospire serovar Lai strain 017.Two recombin ant plasmids pBQ1and pBQ2were constructed by oriented ligation based on the E.coli-BCG shuttle plasmids pMV261and pMV361respectively.The recombinant plasmids were transformed into BCG by electroporation.The rBCGs bearing pBQ1and pBQ2were induced by high temperature of 45℃.Results.The expressed product,a 35kD prote in was detected by SDS-PAGE.The resu lt indicates that pBQ1and pBQ2can express OmpL1in rBCG.Conclusion.The technical methods in this study may help detect the immunogenicity a nd immunoprotection of OmpL1and develop more safe,highl y effective rBCG bearing leptospira l antigen with long-lasting protection.

Deletion of Salmonella enterica serovar typhimurium sipC gene

Objective:To construct a novel plasmid as Salmonella enterica serovar typhimurium(S.typhimurium)sip C gene knockouts candidate.Methods:In this research,50upstream and 30downstream regions of S.typhimurium sip C gene and kanamycin gene were PCR amplified.Each of these DNA fragment was cloned into p GEM T-easy vector.The construct was confirmed by PCR and restriction digest.Results:PCR amplified 320,206 and 835 bp DNA fragments were subcloned into p ET-32 vector resulting with a plasmid called p ET-32-sip C up-kan-sip C down.Conclusions:The new plasmid(p ET-32-sip C up-kan-sip C down)is useful for genetic engineering and for future manipulation of S.typhimurium sip C gene.

Enhancing chloramphenicol and trimethoprim in vitro activity by Ocimum sanctum Linn.(Lamiaceae) leaf extract against Salmonella enterica serovar Typhi

Objective:To evaluate the antibacterial activity of Ocimum sanctum(O.sanctum) leaf extract, alone,and in combination with chloramphenicol(C) and trimethoprim(Tm) against Salmonella enterica serovar Typhi(S.typhi).Methods:The antibacterial activity of ethanolic extract of tulsi, 0.sanctum,leaf(TLE:500μg) for 23 S.typhi isolates was determined following agar diffusion. The C(30μg) and Tm(5μg) activity alone and in combination with TLE(250μg) was determined by disk diffusion.The zone diameter of inhibition(ZDI) for the agents was recorded, and growth inhibitory indices(Glls) were calculated.Results:The S.typhi isolates(n=23),which were resistant to both C(ZDI 6 mm) and Tm(ZDI 6 mm),had TLE(500μg) ZDIs 16-24 mm.The ZDIs of C and Tm were increased up to 15-21 mm and 17-23 mm,respectively,when TLE(250μg) was added to the C and Tm discs.The Glls ranged 0.789-1.235 and 0.894-1.352,due to combined activity against S.typhi isolates,of C and TLE and Tm and TLE.respeclivelv.Conclusions:The data suggest that TLE,in combination with C and Tm,had synergistic activity for S.typhi isolates, and hence O.sanclum is potential in combating S.typhi drug resistance,as well promising in the development of non-antibiotic drug for S.typhi infection.

Identification of a toxin coding fragment in pBSSB1, a linear plasmid from Salmonella enterica serovar Typhi that can stabilize a multicopy plasmid

Objective: To identify the region conferring stability to pBSSB2(a linear plasmid, pBSSB1, containing a kanamycin cassette), which is unique to Indonesian isolates of Salmonella enterica serovar Typhi. Methods: The open reading frame(ORF) 009 was identified as a toxin coding gene in the plasmid through introduction of translational termination codons in the ORF. Results: The stability function was located in a fragment that spanned nucleotides 5 766 to 6 828 in the linear plasmid genetic map. Ectopic expression of ORF009 in pBAD18 vector indicated ORF009 codes for a toxin. This fragment could stabilize plasmid pUC18 previously destabilized through mutation of the pcnB(plasmid copy number control) gene that codes for polyA polymerase. Majority of the cells expressing ORF009 were non-viable according to phase contrast microscopy. Conclusions: This study demonstrated that a linear plasmid fragment that carries a gene encoding a toxin possibly conferred stability to the parent plasmid. It was able to stabilize a multicopy plasmid of Escherichia coli.

ESBL Production and Multidrug Resistance of Salmonella Serovars Isolates in Benue State

Studies on ESBL-producing and multi-drug resistance of Salmonella serovars distributed in Benue State were investigated. A total of four hundred and twenty (420) clinical stool samples, seventy (70) from each local government area were randomly collected from selected hospitals and analyzed for the presence of Salmonella spp. The isolates were characterized using Gram staining and biochemical tests. The result of AP120E biochemical test strip which contained dehydrated bacterial media and biochemical reagents in twenty (20) separate compartments. The result was obtained by evaluation of the compartments due to observed changes in after 24 hours where others were read by adding up reagents (Ferric chloride, Kovacs V.P reagents). The results were analyzed afterwards in accordance with the manufacturer’s software and positive results with ≥89% potential were confirmed as Salmonella spp. Amplified plasmids derived from 18 Salmonella strains recognized were made up of 23,130 base pairs. ESBL (Extended-spectrum beta-lactamases) genes were located on the plasmids. Two of the ESBL genes found were TEM genes and CTX-M (415 bp). Strains such as S. enterica Typhimurium-CP014981.1, S. enterica Enteritidis-CP007325.2, S. enterica Typhimurium-CP024619.1, S. enterica Typhimurium-CP023166.1, S. bongori-FR877557 and S. enterica Enteritidis-TY1 possessed TEM genes where as S. enterica Heidelberg-CP019176.1, S. enterica Typhi-AL513382.1 and S. enterica Typhimurium-MH196335.1 possessed CTX-M. Antibiotic resistance testing was performed using Kirby-Bauer disc diffusion method. The overall percentage susceptibility of the eight antibiotics tested on Salmonella serovars isolates shows that GEN had the highest % susceptibility of 100% followed by NIT (72.2%) and COT (66.7%) before and after plasmid curing. % susceptibility was lower before curing than after curing in CXC, CHL and TET. It was low (5.6%) in ERY while AUG recorded 0% susceptibility. Differences observed in curing status were insignificant (T = 0.33, P > 0.05). The presence of ESBL-producing and multi-drug resistant Salmonella serovars indicates an infection which presents a foremost peril to public health since such infections may be intricate to take care of and may consequently result in death of the infected patients. Constant periodic examination and prevention of drug abuse of antibiotics will assist in ensuring that this trend is curtailed especially in developing nations like Nigeria.

Approach to Epidemiological Mechanism of Infection or Colonization of Egg-Laying Chicken Farms by <i>Salmonella enterica</i>Serovar Enteritidis (SE) Becoming the Main Source of Contamination in Food Poisoning (Review)

Salmonella enterica serovar Enteritidis (SE)-induced diarrhea in humans is the typical non-typhoid diarrhea. It develops acutely or subacutely and may be fatal. This SE infectious disease suddenly became a major public health issue worldwide in the 1980s. The main causative food material of SE food poisoning is chicken eggs, and many outbreaks of food poisoning caused by chicken eggs occurred throughout the world. SE epidemics occurred in layer farms, and this was the main cause of SE-induced food poisoning in humans. The major subject of our epidemiological study described in this report is why SE-contaminated eggs became the main causative food. In this study, we focused on difference of molecular expression for farm-isolated SEs. That is because recent studies have demonstrated that O-antigen enlargement may be related to pathogenicity in mice as well as 22-kDa polypeptide-expression (SEp22). We have discovered that many SE strains isolated from chicken farms do not express SEp22, and a deficiency or decreased level of cellular antigen 0-12 in SE strains isolated from chicken farms was clarified in a report. Additionally, SEp22 was deficient in SE strains passaged through chickens, whereas SEp22 was expressed at a high level in SE strains passaged through mice. These findings suggest that SE infection and retention more effectively occur in layer farms than in other animal maintenance environments, which may be a basis of the epidemiological hypothesis to explain the high-levelproduction of SE-contaminated eggs (the presence of mice may be the basis of the retention of SE infection in layer farms, and this may also be the mechanism causing the high-level production of SE-contaminated eggs).

Complete Genome Sequence of <i>Bacillus thuringiensis</i>Serovar <i>coreanensis</i>ST7 with Toxicity to Human Cancer Cells

Bacillus thuringiensis (Bt) parasporal crystal proteins were well known to be toxic to certain insects and cytocidal activity against various human cancer cells. Bt serovar coreanensis ST7, non-pathogenic to insects and non-hemolytic, has an important parasporin, PS4Aa1 (Cry45Aa1), with potential toxicity to human cancer cells. In this study, we reported the feature of complete genome sequence and the cluster of orthologous groups of proteins function classification of ST7. Meanwhile, the evolutionary of ST7 was also studied. The genome data of ST7 will strongly contribute to a better understanding of the genomic diversity and evolution, and enrich the Bt genome database.

Analysis of Prevalent Leptospira Serovar in Different Animals of South Gujarat Region during the Year of 2020

Aim of Study: Leptospirosis is a bacterial zoonotic disease transmitted through contact with animals that are harbouring leptospira. Knowledge of prevalent leptospira in a particular animal of a particular geographical area is essential to understand the epizootiology of disease, to understand the linkage between circulating serovars in animals and in humans, and to apply appropriate control measures, etc. Material and Methods: Animal samples from different districts of the south Gujarat region received in the Microbiology department during the year of 2020 for the Microscopic agglutination test (MAT) of leptospirosis were included in the study. Results of MAT which was already performed using 12 different serovars were analysed to prevent serovars in a particular animal. Quantitative data were analysed using frequency and percentage. Result: Out of 1406 animal samples, 151 (11 percent) were positive from animals like cows, buffalos, bullocks and goats. More prevalent serovars in cows were L. ictrohemorrahiae (22%), L. hardjo (19%), L. patoc (17%) and L. pyrogen (16%). In buffalo, L. patoc (58%) and L. hardjo (27%) were found. L. hardjo (50%) in bullock and L. automonalis (50%), L. australis (22%) and L. patoc (14%) in goat were found as prevent serovars. Conclusion: Different prevent serovars has been observed in different animals from the different district south Gujarat region which will be helpful to trace the source of infection in human, to apply control measures, to know the epizootiology of disease, for developing strategies in the future during vaccine development with emphasizing more on the prevalent serovars.

Response of Salmonella enterica serovar Typhimurium to alginate oligosaccharides fermented with fecal inoculum:integrated transcriptomic and metabolomic analyses

Alginate oligosaccharides(AOS),extracted from marine brown algae,are a common functional feed additive;however,it remains unclear whether they modulate the gut microbiota and microbial metabolites.The response of Salmonella enterica serovar Typhimurium,a common poultry pathogen,to AOS fermented with chicken fecal inocula was investigated using metabolomic and transcriptomic analyses.Single-strain cultivation tests showed that AOS did not directly inhibit the growth of S.Typhimurium.However,when AOS were fermented by chicken fecal microbiota,the supernatant of fermented AOS(F-AOS)exhibited remarkable antibacterial activity against S.Typhimurium,decreasing the abundance ratio of S.Typhimurium in the fecal microbiota from 18.94 to 2.94%.Transcriptomic analyses showed that the 855 diferentially expressed genes induced by F-AOS were mainly enriched in porphyrin and chlorophyll metabolism,oxidative phosphorylation,and Salmonella infection-related pathways.RT-qPCR confrmed that F-AOS downregulated key genes involved in fagellar assembly and the type III secretory system of S.Typhimurium,indicating metabolites in F-AOS can infuence the growth and metabolism of S.Typhimurium.Metabolomic analyses showed that 205 microbial metabolites were signifcantly altered in F-AOS.Among them,the increase in indolelactic acid and 3-indolepropionic acid levels were further confrmed using HPLC.This study provides a new perspective for the application of AOS as a feed additive against pathogenic intestinal bacteria.

1例感染鼠伤寒沙门菌伴呕吐患者的护理体会

本文总结1例感染鼠伤寒沙门菌伴呕吐患者的护理经验,包括肠道传染病隔离措施、呕吐护理、心理护理、病情观察、饮食护理等护理措施,通过积极有效的护理措施预防并发症,改善患者症状,促进患者早日康复。

伤寒沙门菌外膜囊泡通过调控铁死亡抑制结直肠癌细胞的增殖及机制初探

近年来,细菌外膜囊泡(OMVs)在抗肿瘤治疗中展现出的巨大潜力引起了广泛的关注.为探究伤寒沙门菌外膜囊泡(S.Typhi-OMVs)对人结直肠癌细胞株HT-29增殖的影响及可能的作用机制,通过超速离心法提取不同细菌的OMVs,细胞增殖实验(CCK-8)检测各细菌OMVs对细胞活力的影响;转录组测序(RNA-seq)分析处理后细胞基因表达水平的变化;试剂盒检测铁死亡相关标志物的含量变化;实时荧光定量PCR(qRT-PCR)和蛋白质免疫印迹法(western blot)分别检测相关基因mRNA和蛋白质的表达变化.结果显示,在提取的6种细菌OMVs中,S.Typhi-OMVs对HT-29细胞的增殖产生了最明显的抑制作用,并且呈现出浓度和时间梯度依赖性;RNA-seq显示HT-29细胞可能发生了铁死亡;S.Typhi-OMVs作用后,细胞内发生了铁沉积,氧化产物增多,抗氧化剂减少,符合铁死亡生化特征;SAT1是S.Typhi-OMVs处理后HT-29胞内mRNA表达量变化最大的基因;p53-SAT1-ALOX15是铁死亡的信号通路之一,S.Typhi-OMVs处理后胞内p53、SAT1、ALOX15的mRNA与蛋白表达均增高.以上结果表明,S.Typhi-OMVs能够抑制结直肠癌细胞HT-29的增殖,其机制可能与通过p53-SAT1-ALOX15信号通路诱导HT-29发生铁死亡有关.

基于平均核苷酸相似度和16S rDNA技术对全球沙门氏菌的鉴定比对分析

目的评估平均核苷酸相似度(average nucleotide identity,ANI)和16S rDNA技术对沙门氏菌的鉴定能力。方法从GenBank数据库批量下载全球沙门氏菌基因组和相应血清型,以沙门氏菌典型菌株的基因组作为分型菌株。利用fastANI软件,根据默认参数进行ANI分析。使用在线软件SpeciesFinder针对细菌的16S rDNA进行物种和血清型鉴定。结果在下载的2306个基因组中,1767株沙门氏菌存在178种血清型,以鼠伤寒沙门菌323株(18.3%)和肠炎沙门菌300株(17.0%)最为常见。ANI分析显示,以95%为界值时,仅有30株(1.3%)沙门氏菌被分配到1个特定的亚种,其余2276株(98.7%)沙门氏菌均可分配到2~5个亚种;以97%为界值时,2306株(100%)沙门氏菌均可被鉴定到唯一的亚种。基于16S rDNA的分析仅鉴定出1072株(46.5%)沙门氏菌,其中95.2%(1021/1072)的沙门氏菌鉴定的亚种结果与ANI(≥97%)分析鉴定的结果完全一致;与已知的血清型相比,仅有2.4%(19/784)的沙门氏菌与已知的血清型结果一致。结论ANI更适合沙门氏菌的种及亚种鉴定,ANI≥97%可作为沙门氏菌亚种的鉴定标准。16S rDNA技术对于沙门氏菌鉴定的敏感性尚有待提高。

胸膜肺炎放线杆菌利用肠菌素摄取铁促生长的研究

肠菌素(Ent)介导的铁摄取系统在病原细菌生长和定植过程中发挥关键作用。胸膜肺炎放线杆菌是引起猪传染性胸膜肺炎的病原,为鉴定该菌不同血清型菌株能否利用肠菌素摄取铁发挥促生长作用,试验选用胸膜肺炎放线杆菌血清1~12型参考菌株,首先在限铁条件下通过肠菌素促生长试验鉴定不同血清型菌株能否利用肠菌素;进而通过添加不同浓度的铁螯合剂DFO、细菌接种量、肠菌素等因子,筛选胸膜肺炎放线杆菌利用肠菌素促生长的最适培养条件;最后分别在限铁和富铁培养条件下通过生长曲线鉴定肠菌素对胸膜肺炎放线杆菌12个血清型菌株的促生长作用。结果显示,在测定的胸膜肺炎放线杆菌血清1~12型参考菌株中,除血清2型和10型外,其他型菌株在限铁条件下均可利用肠菌素促生长。不同因子筛选结果显示,最适细菌接种浓度为1×10^(4)CFU/mL,添加DFO浓度为20μmol/L,而添加0.4、2.0、10.0μg/mL等不同浓度的肠菌素对胸膜肺炎放线杆菌均有显著促生长作用,且随肠菌素浓度升高而促生长能力显著增强。试验证实胸膜肺炎放线杆菌可利用肠菌素促进其生长,同时证实不同血清型利用肠菌素方面存在显著差异,为解析肠菌素介导的铁摄取系统在胸膜肺炎放线杆菌中的作用机制奠定了基础。

Identification of in vivo induced protein antigens of Salmonella enterica serovar Typhi during human infection

During infectious disease episodes, pathogens express distinct subsets of virulence factors which allow them to adapt to different environments. Hence, genes that are expressed or upregulated in vivo are implicated in pathogenesis. We used in vivo induced antigen technology (IVIAT) to identify antigens which are expressed during infection with Salmonella enterica serovar Typhi. We identified 7 in vivo induced (IVI) antigens, which included BcfD (a fimbrial structural subunit), GrxC (a glutaredoxin 3), SapB (an ABC-type transport system), T3663 (an ABC-type uncharacterized transport system), T3816 (a putative rhodanese-related sulfurtransferase), T1497 (a probable TonB-dependent receptor) and T3689 (unknown function). Of the 7 identified antigens, 5 antigens had no cross-immunoreactivity in adsorbed control sera from healthy subjects. These 5 included BcfD, GrxC, SapB, T3663 and T3689. Antigens identified in this study are potential targets for drug and vaccine development and may be utilized as diagnostic agents.

A Salmonella enterica serovar Typhi plasmid induces rapid and massive apoptosis in infected macrophages

pRST98 is a chimeric plasmid isolated from Salmonella enterica serovar Typhi(S.typhi)that mediates the functions of drug resistance and virulence.Previously,we reported that Salmonella plasmid virulence(spv)genes were present in S.typhi.In our current study,we investigated whether plasmid pRST98 exhibits significant cytotoxicity in macrophages.pRST98 was transferred into the avirulent Salmonella enterica serovar Typhimurium(S.typhimurium)strain RIA to create the transconjugant pRST98/RIA.The standard S.typhimurium virulent strain SR-11,which carries a 100-kb virulence plasmid,was used as a positive control.The bacterial strains were incubated with a murine macrophage-like cell line(J774A.1)in vitro.Apoptosis of J774A.1 cells was examined by electron microscopy and flow cytometry after annexin-V/propidium iodide labeling,and the survival of Salmonella strains in J774A.1 cells was determined.Results showed that macrophages infected with strain pRST98/RIA displayed greater levels of apoptosis than those infected with RIA and that pRST98 may increase bacterial survival in macrophages.Further studies showed that the pRST98-induced death of macrophages was associated with the loss of mitochondrial membrane potential and that pRST98 may activate caspase-9 and then caspase-3.The research data indicate that the virulence of bacteria that contain the pRST98 plasmid is enhanced;the presence of this plasmid increases the survival of the bacterial pathogen and acts through the mitochondrial pathway to mediate macrophage apoptosis.

Detection of Plasmid-Mediated Tigecycline Resistance Gene tet(X4) in a Salmonella enterica Serovar Llandoff Isolate

The emergence and spread of plasmid-mediated tigecycline resistance genes have attracted extensive attention worldwide.We investigated the distribution of mobile tigecycline resistance genes in Salmonella genomes generated by both our laboratory and public bacterial genomes downloaded from the NCBI GenBank.The tet(X4)-positive strains were subjected to susceptibility testing and conjugation assays.The genetic features of the tet(X4)-bearing plasmid sequence were analyzed.Here,we report the identification of the plasmid-mediated tigecycline resistance gene tet(X4)in a conjugative plasmid of the Salmonella enterica serovar Llandoff strain SH16G3606,isolated from a man in China in 2016,the first reported serovar Llandoff in China as a novel sequence type ST8300.The tet(X4)-mediated resistance phenotype was successfully transferred from the Salmonella Llandoff strain into Escherichia coli J53,resulting in a 32-fold increase in the minimal inhibitory concentration of tigecycline.The tet(X4)gene was located between two copies of ISCR2 in the plasmid pSal21GXH-tetX4.To our knowledge,this is the first report of the plasmid-mediated tigecycline resistance gene tet(X4)in a Salmonella Llandoff strain isolated from a human stool sample in China.In addition,our findings demonstrated that a total of 171 isolates are carrying tet(X)-like genes distributed in 21 countries or areas across 6 continents,posing a serious threat to humans and public health.Overall,our timely discovery of the recent emergence of the tet(X4)gene in Salmonella isolates and other Enterobacteriaceae bacteria species supports the need for rapid surveillance to prevent the tet(X)-like gene from spreading.

Lymphogranuloma venereum caused by Chlamydia trachomatis serovar L3:a case report

Lymphogranuloma venereum （LGV） is a systemic sexually transmitted disease caused by Chlamydia trachomatis （C. trachomatis） L1, L2 and L3, the organism gains entrance through skin breaks and abrasions and travels via the lymphatics to multiply within mononuclear phagocytes in regional lymph nodes, The clinical presentation of LGV depends on the sex of the patient, mode of sexual contact （e.g. vaginal or anal sex） and the stage of the disease. LGV is diagnosed in men up to 6 times more frequently than in women, but the infected women are more likely developed to late stage. LGV is rare in China, however the incidence was increasing in recent years. In this paper we diagnosed a case of LGV, and confirmed this case was caused by L3 serovar of C. trachomatis by using genotype test.

Molecular characterization and antibiotic resistance of Salmonella enterica serovar 1,4,[5],12:i:-environmental isolates from poultry farms

Salmonella enterica serovar 1,4,[5],12:i:-(S.1,4,[5],12:i:-)has been recognized as an emerging foodborne pathogen in recent years.It can cause human salmonellosis predominated by the contamination of animal-derived foods such as raw poultry and pork.This study aimed to characterize the genetic diversity,plasmid replicon types,and antibiotic resistance of 15 S.1,4,[5],12:i:-environmental isolates collected from two poultry farms using pulsed-field gel electrophoresis(PFGE),multilocus sequence typing(MLST),polymerase chain reaction-based replicon typing,and minimum inhibitory concentration approach.Ten different PFGE genotypes were detected,indicating a high diversity among these S.1,4,[5],12:i:-isolates.Three sequence types(ST19,ST1544,ST34)were identified by MLST.Among them,ST1544 was first detected in S.1,4,[5],12:i:-environmental isolates from poultry farms.All isolates were resistant to cefazolin,cefotetan,tobramycin,amikacin,and gentamicin,but susceptible to piperacillin-tazobactam,aztreonam,ceftazidime,cefepime,and ertapenem.Five incompatibility groups(Inc)of plasmids were identified,including IncFIIs(66.7%),IncHI2(20%),IncI1(6.7%),IncN(6.7%),and IncQ(6.7%).Among these isolates,80%carried at least one plasmid replicon type,and 20%carried multiple plasmid replicon types.Interestingly,the multidrug-resistant isolate 263 carried numerous resistance genes(i.e.qnrS,aac(6ʹ)-Ib-cr,bla_(TEM),bla_(CTX-M-9),bla_(OXA-1),sul1,sul2,sul3,floR,and mcr-1)and class I integronase gene intI1,which possessed both IncHI2 and IncQ plasmids,suggesting that resistance genes may be horizontally transferred by the combination of IncHI2 and IncQ plasmids.Collectively,antibiotic-resistant S.1,4,[5],12:i:-isolates were first found in poultry farm environments in China,and surveillance should be strengthened to prevent their further spread from poultry farms to foods.