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Objectives: Campylobacter is a significant zoonotic pathogen primarily transmitted through poultry. Our study aimed to assess antimicrobial resistance and genetic relationships among Campylobacter isolates from retail chicken meat and humans in Taiwan., Methods: Campylobacter isolates were analysed using whole-genome sequencing to investigate their antimicrobial resistance, genetic determinants of resistance, and genotypes., Results: Campylobacter coli and Campylobacter jejuni accounted for 44.9% and 55.1% of chicken meat isolates, and 11.4% and 88.6% of human isolates, respectively. C. coli displayed significantly higher resistance levels. Furthermore, isolates from chicken meat exhibited higher levels of resistance to most tested antimicrobials compared to isolates from humans. Multidrug resistance was observed in 96.3% of C. coli and 43.3% of C. jejuni isolates from chicken meat and 80.6% of C. coli and 15.8% of C. jejuni isolates from humans. Macrolide resistance was observed in 85.5% of C. coli isolates, primarily attributed to the erm(B) rather than the A2075G mutation in 23S rRNA. Among the 511 genomes, we identified 133 conventional MLST sequence types, indicating significant diversity among Campylobacter strains. Notably, hierarchical Core-genome multilocus sequence typing clustering, including HC0, HC5, and HC10, revealed a significant proportion of closely related isolates from chicken meat and humans., Conclusions: Our research highlights significant associations in antimicrobial resistance and genetic relatedness between Campylobacter isolates from chicken meat and humans in Taiwan. The genetic analysis data suggest that campylobacteriosis outbreaks may occur more frequently in Taiwan than previously assumed. Our study emphasizes the need for strategies to control multidrug-resistant strains and enhance outbreak prevention., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Carbapenem-resistant Enterobacter cloacae complex is a significant global healthcare threat, particularly carbapenemase-producing Enterobacter hormaechei (CPEH). From January 2017 to January 2021, twenty-two CPEH isolates from a regional teaching hospital in central Taiwan were identified with the carriage of carbapenemase genes bla KPC-2 , bla IMP-8 , and predominantly bla OXA-48 . Over 80% of these CPEH strains clustered into the high-risk ST78 lineage, carrying a bla OXA-48 IncL plasmid (pOXA48-CREH), nearly identical to the endemic plasmid pOXA48-KP in ST11 Klebsiella pneumoniae . This OXA-48-producing ST78 lineage disseminated clonally from 2018 to 2021 and transferred pOXA48-CREH to ST66 and ST90 E. hormaechei . An IMP-8-producing ST78 strain harbouring a bla IMP-8 -carrying pIncHI2 plasmid appeared in 2018, and by late 2020, a KPC-2-producing ST78 strain was identified after acquiring a novel bla KPC-2 -carrying IncFII plasmid. These findings suggest that the high-risk ST78 lineage of E . hormaechei has emerged as the primary driver behind the transmission of CPEH . ST78 has not only acquired various carbapenemase-gene-carrying plasmids but has also facilitated the transfer of pOXA48-CREH to other lineages. Continuous genomic surveillance and targeted interventions are urgently needed to control the spread of emerging CPEH clones in hospital settings.

Phototherapy has been extensively used to prevent and treat signs of aging and stimulate wound healing, and phototherapy through light-emitting diodes (LEDs). In contrast to LED, organic LED (OLED) devices are composed of organic semiconductors that possess novel characteristics. We investigated the regenerative potential of OLED for restoring cellular potential from senescence and thus delaying animal aging. Bone marrow-derived stem cells (BMSCs) and adipose-derived stem cells (ADSCs) were isolated from the control and OLED- treated groups to evaluate their proliferation, migration, and differentiation potentials. Cellular senescence was evaluated using a senescence-associated β-galactosidase (SA-β-gal) activity assay and gene expression biomarker assessment. OLED treatment significantly increased the cell proliferation, colony formation, and migration abilities of stem cells. SA-β-gal activity was significantly decreased in both ADSCs and BMSCs in the OLED-treated group. Gene expression biomarkers from treated mice indicated a significant upregulation of IGF-1 (insulin growthfactor-1). The upregulation of the SIRT1 gene inhibited the p16 and p19 genes then to downregulate the p53 expressions for regeneration of stem cells in the OLED-treated group. Our findings indicated that the survival rates of 10-month aging senescence-accelerated mouse prone 8 mice were prolonged and that their gross appearance improved markedly after OLED treatment. Histological analysis of skin and brain tissue also indicated significantly greater collagen fibers density, which prevents ocular abnormalities and β-amyloid accumulation. Lordokyphosis and bone characteristics were observed to resemble those of younger mice after OLED treatment. In conclusion, OLED therapy reduced the signs of aging and enhanced stem-cell senescence recovery and then could be used for tissue regeneration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

While the incidence of shigellosis has decreased in developed nations due to improved living conditions and healthcare systems, it remains prevalent in economically developing regions. In recent years, a resurgence of shigellosis has been observed in the United States, Europe, and Taiwan, primarily among men having sex with men and people living with human immunodeficiency virus, along with a rise in antimicrobial resistance. This study aims to review the historical epidemiological trends and drug resistance in shigellosis, with a focus on Taiwan. A comprehensive search was conducted using various databases and sources, including non-English literature in Japanese and Chinese. In developed countries, Shigella sonnei and Shigella flexneri are the most common species, while Shigella dysenteriae infections are sporadic. In Taiwan, the classification and prevalence of Shigella species have evolved over time, with S. flexneri and S. sonnei being the predominant strains. Fluoroquinolone resistance and azithromycin non-susceptibility are the ongoing threat. In conclusion, shigellosis remains a significant global health concern, with recent increases in certain populations and antimicrobial resistance. Further research is necessary to understand the clinical significance and risk factors associated with asymptomatic carriers and to assess the impact of behavioral modifications and interventions in high-risk populations., (Copyright © 2023. Published by Elsevier B.V.)

Objectives: Salmonella , a zoonotic pathogen, significantly impacts global human health. Understanding its serotype distribution and antimicrobial resistance is crucial for effective control measures and medical interventions., Methods: We collected Salmonella isolates and demographic data from Taiwanese hospitals between 2004 and 2022, analyzing their serotypes and antimicrobial susceptibility., Results: Among 40,595 isolates, salmonellosis predominated in children aged 0-4 (61.2%) years and among males (55.2%). Males also showed higher rates of extraintestinal infections (18.1% vs 16.0%, P <0.001), particularly, in the ≥65 years age group (52.4%). The top five serovars were S. Enteritidis (32.8%), S. Typhimurium (21.7%), S. Newport (6.2%), S. Stanley (4.7%), and S. Anatum (4.0%). Notably, S . Enteritidis prevalence increased from 23.9% (2004-2005) to 43.6% (2021-2022). Antimicrobial resistance was high, with a 51.6% multidrug resistance (MDR) rate. Disturbingly, MDR rates exceeded 90% in serovars Albany, Schwarzengrund, Choleraesuis, and Goldcoast. Resistance to key therapeutic agents, azithromycin, cefotaxime, and ciprofloxacin, exhibited concerning upward trends, and the surge in cefotaxime and ciprofloxacin resistance was closely linked to the emergence and spread of MDR S. Anatum and S. Goldcoast clones., Conclusions: Prioritizing control measures against S . Enteritidis and closely monitoring the prevalence and spread of MDR clones are imperative to mitigate Salmonella infections in Taiwan., Competing Interests: The authors have no competing interests to declare., (© 2024 The Author(s).)

Carbapenem-resistant ST11&#95;KL64 Klebsiella pneumoniae emerged as a significant public health concern in Taiwan, peaking between 2013 and 2015, with the majority of isolates exhibiting OXA-48 as the sole carbapenemase. In this study, we employed whole-genome sequencing to investigate the molecular underpinnings of ST11&#95;KL64 isolates collected from 2013 to 2021. Phylogenomic analysis revealed a notable genetic divergence between the ST11&#95;KL64 strains in Taiwan and those in China, suggesting an independent evolutionary trajectory. Our findings indicated that the ST11&#95;KL64&#95;Taiwan lineage originated from the ST11&#95;KL64 lineage in Brazil, with recombination events leading to the integration of ICE Kp11 and a 27-kb fragment at the tRNA ASN sites, shaping its unique genomic landscape. To further elucidate this unique sublineage, we examined the plasmid contents. In contrast to ST11&#95;KL64&#95;Brazil strains, which predominantly carried bla KPC-2 , ST11&#95;KL64&#95;Taiwan strains exhibited the acquisition of an epidemic bla OXA-48 -carrying IncL plasmid. Additionally, ST11&#95;KL64&#95;Taiwan strains consistently harbored a multi-drug resistance IncC plasmid, along with a collection of gene clusters that conferred resistance to heavy metals and the phage shock protein system via various Inc-type plasmids. Although few, there were still rare ST11&#95;KL64&#95;Taiwan strains that have evolved into hypervirulent CRKP through the horizontal acquisition of pLVPK variants. Comprehensive characterization of the high-risk ST11&#95;KL64 lineage in Taiwan not only sheds light on its epidemic success but also provides essential data for ongoing surveillance efforts aimed at tracking the spread and evolution of ST11&#95;KL64 across different geographical regions. Understanding the molecular underpinnings of CRKP evolution is crucial for developing effective strategies to combat its emergence and dissemination., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Wang, Chen, Tang, Chen, Teng, Chiou, Lu and Lai.)

Objectives: We investigated the temporal trends of Salmonella enterica serovar Typhimurium (S. Typhimurium) clones in Taiwan from 2004 to 2019, focusing on antimicrobial resistance (AMR), resistance genetic determinants, and plasmid types., Methods: Salmonella isolates were characterized using pulsed-field gel electrophoresis (PFGE), whole-genome sequencing, and antimicrobial susceptibility testing. Clones were defined using PFGE clustering and the hierarchical cgMLST clustering (HierCC) assignments., Results: Seven major S. Typhimurium clones, HC100&#95;2, 13, 41, 305, 310, 501, and 46261, accounted for 97.6% (8079/8275) of human isolates in Taiwan. Each clone displayed a unique AMR profile, resistance genetic determinants, and plasmid types. Four highly resistant clones (HC100&#95;2, 41, 305, and 310) exhibited multiple resistance in 86.5% to 96.1% of isolates. HC100&#95;305 and HC100&#95;2 were pandemic multidrug-resistant clones, characterized by resistance to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline (ACSSuT) and ASSuT, respectively. The prevalence of the ACSSuT clone decreased from 68.7% of S. Typhimurium isolates in 2004 to 1.7% in 2019, while the ASSuT clone emerged in 2007 and became the largest clone after 2010. Several plasmids, including IncHI2-IncHI2A, IncC, IncFIB(K), and IncI1-1(α), carried multiple resistance genes or were associated with the carriage of mph(A), bla CMY-2 , and bla DHA-1 ., Conclusions: Between 2004 and 2019, Taiwan experienced the emergence, prevalence, and subsequent decline of several highly resistant S. Typhimurium clones. The clones defined using the HierCC approach have global comparability. The increasing resistance to third-generation cephalosporins, cephamycins, ciprofloxacin, and azithromycin in recent years poses a significant medical concern., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The accuracy of Oxford Nanopore Technology (ONT) sequencing has significantly improved thanks to new flowcells, sequencing kits, and basecalling algorithms. However, novel modification types untrained in the basecalling models can seriously reduce the quality. Here we reports a set of ONT-sequenced genomes with unexpected low quality due to novel modification types. Demodification by whole-genome amplification significantly improved the quality but lost the epigenome. We also developed a reference-based method, Modpolish, for correcting modification-mediated errors while retaining the epigenome when a sufficient number of closely-related genomes is publicly available (default: top 20 genomes with at least 95% identity). Modpolish not only significantly improved the quality of in-house sequenced genomes but also public datasets sequenced by R9.4 and R10.4 (simplex). Our results suggested that novel modifications are prone to ONT systematic errors. Nevertheless, these errors are correctable by nucleotide demodification or Modpolish without prior knowledge of modifications., (© 2023. The Author(s).)

A CTX-M-65‒producing Salmonella enterica serovar Infantis clone, probably originating in Latin America and initially reported in the United States, has emerged in Taiwan. Chicken meat is the most likely primary carrier. Four of the 9 drug resistance genes have integrated into the chromosome: bla CTX-M-65 , tet(A), sul1, and aadA1.

We identified an erm42 -carrying integrative and conjugative element, ICE&#95;erm42, in 26.4% of multidrug-resistant Salmonella enterica serovar Albany isolates recovered from human salmonellosis between 2014 and 2019 in Taiwan. ICE&#95;erm42-carrying strains displayed high-level resistance to azithromycin and the element could move into the phylogenetically distant Vibrio cholerae via conjugation., (Copyright © 2021 American Society for Microbiology.)

Antimicrobial resistance was investigated in 2,341 nontyphoidal Salmonella (NTS) isolates recovered from humans in Taiwan from 2017 to 2018 using antimicrobial susceptibility testing. Azithromycin resistance determinants were detected in 175 selected isolates using PCR and confirmed in 81 selected isolates using whole-genome sequencing. Multidrug resistance was found in 47.3% of total isolates and 96.2% of Salmonella enterica serovar Anatum and 81.7% of S. enterica serovar Typhimurium isolates. Resistance to the conventional first-line drugs (ampicillin, chloramphenicol, and cotrimoxazole), cefotaxime and ceftazidime, and ciprofloxacin was found in 32.5 to 49.0%, 20.3 to 20.4%, and 3.2% of isolates, respectively. A total of 76 (3.1%) isolates were resistant to azithromycin, which was associated with mph (A), erm (42), erm (B), and possibly the enhanced expression of efflux pump(s) due to ramAp or defective ramR . mph (A) was found in 53% of the 76 azithromycin-resistant isolates from 11 serovars and located in an IS 26 - mph (A) -mrx (A) -mphR (A)-IS 6100 unit in various incompatibility plasmids and the chromosomes. erm (42) in S. enterica serovar Albany was carried by an integrative and conjugative element, ICE&#95;erm42, and in S. enterica serovar Enteritidis and S. Typhimurium was located in IS 26 composite transposons in the chromosomes. erm (B) was carried by IncI1-I(α) plasmids in S. Enteritidis and S. Typhimurium. ramAp was a plasmid-borne ramA , a regulatory activator of efflux pump(s), found in only S. enterica serovar Goldcoast. Since the azithromycin resistance determinants are primarily carried on mobile genetic elements, they could easily be disseminated among human bacterial pathogens. The ramAp -carrying S. Goldcoast isolates displayed azithromycin MICs of 16 to 32 mg/L. Thus, the epidemiological cutoff value of ≤16 mg/L of azithromycin proposed for wild-type NTS should be reconsidered. IMPORTANCE Antimicrobial resistance in NTS isolates is a major public health concern in Taiwan, and the mechanisms of azithromycin resistance are rarely investigated. Azithromycin and carbapenems are the last resort for the treatment of invasive salmonellosis caused by multidrug-resistant (MDR) and extensively drug-resistant Salmonella strains. Our study reports the epidemiological trend of resistance in NTS in Taiwan and the genetic determinants involved in azithromycin resistance. We point out that nearly half of NTS isolates from 2017 to 2018 are MDR, and 20% are resistant to third-generation cephalosporins. The azithromycin resistance rate (3.1%) for the NTS isolates from Taiwan is much higher than those for the NTS isolates from the United States and Europe. Our study also indicates that azithromycin resistance is primarily mediated by mph (A), erm (42), erm (B), and ramAp , which are frequently carried on mobile genetic elements. Thus, the azithromycin resistance determinants could be expected to be disseminated among diverse bacterial pathogens.

Listeria monocytogenes is a life-threatening foodborne pathogen. Here, we report the genomic characterization of a nationwide dataset of 411 clinical and 82 food isolates collected in Taiwan between 2014 and 2019. The observed incidence of listeriosis increased from 0.83 to 7 cases per million population upon implementation of mandatory notification in 2018. Pregnancy-associated cases accounted for 2.8% of human listeriosis and all-cause 7-day mortality was of 11.9% in nonmaternal-neonatal listeriosis. L. monocytogenes was isolated from 90% of raw pork and 34% of chicken products collected in supermarkets. Sublineages SL87, SL5, and SL378 accounted for the majority (65%) of clinical cases. SL87 and SL378 were also predominant (57%) in food products. Five cgMLST clusters accounted for 57% clinical cases, suggesting unnoticed outbreaks spanning up to 6 years. Mandatory notification allowed identifying the magnitude of listeriosis in Taiwan. Continuous real-time genomic surveillance will allow reducing contaminating sources and disease burden. IMPORTANCE Understanding the phylogenetic relationship between clinical and food isolates is important to identify the transmission routes of foodborne diseases. Here, we performed a nationwide study between 2014 and 2019 of both clinical and food Listeria monocytogenes isolates and sequenced their genomes. We show a 9-fold increase in listeriosis reporting upon implementation of mandatory notification. We found that sublineages SL87 and SL378 predominated among both clinical (50%) and food (57%) isolates, and identified five cgMLST clusters accounting for 57% of clinical cases, suggestive of potential protracted sources of contamination over up to 6 years in Taiwan. These findings highlight that mandatory declaration is critical in identifying the burden of listeriosis, and the importance of genome sequencing for a detailed characterization of the pathogenic L. monocytogenes genotypes circulating in Asia.

Shigellosis appears to increase in certain at-risk populations in developed countries. Based on the nationwide surveillance, the annual incidence of shigellosis in Taiwan (1999-2019) was 0.38-5.77 cases per 100,000 people. Indigenous shigellosis has mostly affected men who have sex with men (MSM) and people living with HIV (PLWH) since 2015. In this retrospective study, compared with those diagnosed before 2015, indigenous cases diagnosed during 2015-2019 mostly occurred in male adults (96.0% vs 47.1%, P  < 0.001), with a longer hospital stay (median 5.0 vs 3.5 days, P  = 0.029) and different coinfections. The predominant strains in 2015 and 2016 were ciprofloxacin-resistant Shigella sonnei and azithromycin non-susceptible Shigella flexneri ( S. flexneri ) 3a, which had been replaced by ciprofloxacin-resistant S. flexneri 2a since 2018. Notably, six indigenous cases were caused by cefotaxime-resistant S. flexneri . Inappropriate use of empiric antibiotic treatment was common. In conclusion, there is an ongoing spread of ciprofloxacin-resistant shigellosis among PLWH and MSM and cefotaxime-resistant S. flexneri is an emerging threat in Taiwan.

Particulate matter (PMs) from combustion emissions (traffic, power plant, and industries) and the novel coronavirus (COVID-19) pandemic have recently enhanced the development of personal protective equipment against airborne pathogens to protect humans' respiratory system. However, most commercial face masks still cannot simultaneously achieve breathability and high filtration of PMs, bacteria, and viruses. This study used the electrospinning method with polyimide (PI) and polyethersulfone (PES) solutions to form a nanofiber membrane with low-pressure loss and high biocompatibility for high-efficiency bacteria, viruses, and nano-aerosol removal. Conclusively, the optimized nano-sized PI/PES membrane (0.1625 m 2 /g basis weight) exhibited conspicuous performance for the highest filtration efficiency towards PM from 50 to 500 nm (99.74 %), good filter quality of nano-aerosol (3.27 Pa -1 ), exceptional interception ratio against 100-nm airborne COVID-19 (over 99 %), and non-toxic effect on the human body (107 % cell viability). The PI/PES nanofiber membrane required potential advantage to form a medical face mask because of its averaged 97 % BEF on Staphylococcus aureus filiation and ultra-low pressure loss of 0.98 Pa by referring ASTM F2101-01. The non-toxic PI/PES filters provide a new perspective on designing excellent performance for nano-aerosols from air pollution and airborne COVID-19 with easy and comfortable breathing under ultra-low air flow resistance., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.)

CG23-I lineage constitutes the majority of hypervirulent Klebsiella pneumoniae. A diabetic patient suffered six episodes of infections caused by CG23-I K. pneumoniae. A total of nine isolates were collected in 2020. We performed whole-genome sequencing to elucidate the within-patient evolution of CG23-I K. pneumoniae. The maximum pairwise difference among the nine longitudinally collected isolates was five single nucleotide polymorphisms. One of the mutations was at the Asp87 position of GyrA. Four indels were identified, including an initiator tRNAfMet duplication, a tRNAArg deletion, a 7-bp insertion, and a 22-bp deletion. All 9 isolates had the genomic features of CG23-I K. pneumoniae, a chromosome-borne ICE Kp10 , and a large virulence plasmid. The carriage of a complete set of genes for the biosynthesis of colibactin by ICE Kp10 gave the nine isolates an ability to cause DNA damage to RAW264.7 cells. Compared with the initial isolate, the last isolate with an additional copy of initiator tRNA fMet grew faster in a nutrient-limiting condition and exhibited enhanced virulence in BALB/c mice. Collectively, we characterized the within-patient microevolution of CG23-I K. pneumoniae through an in-depth comparison of genome sequences. Using the in vitro experiments and mouse models, we also demonstrated that these genomic alterations endowed the isolates with advantages to pass through in vivo selection. IMPORTANCE CG23-I is a significant lineage of hypervirulent Klebsiella pneumoniae. This study characterizes the within-patient microevolution of CG23-I K. pneumoniae. Selective pressures from continuous use of antibiotics favored point mutations contributing to bacterial resistance to antibiotics. The duplication of an initiator tRNA fMet gene helped CG23-I K. pneumoniae proliferate to reach a maximal population size during infections. For longer persistence inside a human host, the large virulence plasmid evolved with more flexible control of replication through duplication of the iteron-1 region. With the genomic alterations, the last isolate had a growth advantage over the initial isolate and exhibited enhanced virulence in BALB/c mice. This study gives us a deeper understanding of the genome evolution during the within-patient pathoadaptation of CG23-I K. pneumoniae.

We present the demographic features of invasive meningococcal disease (IMD) in Taiwan between 1993 and 2020 and the genetic characteristics of Neisseria meningitidis isolates recovered from 2003 to 2020. IMD was rare in Taiwan between 1993 and 2020, with an annual incidence ranging from 0.009 to 0.204 per 100,000 people. The case fatality rate (CFR) declined from 18.1% for patients in 1993 to 2002 to 9.8% in 2003 to 2020. Infants less than 12 months were most susceptible to the disease. N. meningitidis serogroup B (NmB) was most predominant, responsible for 81.2% (134/165) of the IMD cases in 2003 to 2020. The majority of the isolates recovered from 2003 to 2020 belonged to 4 worldwide-spread hyperinvasive clonal complexes (cc), cc4821 (30.3%), cc32 (19.4%), cc41/44 (12.7%), cc23 (7.3%), and also a newly assigned clonal complex, cc3439 (10.3%). Core genome multilocus sequence typing (cgMLST) profile comparisons revealed that the cc4821 isolates with a T-to-I substitution at position 91 in gyrA were closely related to those originating from China. Of the 165 isolates, 20.0% and 53.3% were predicted to be covered by the Bexsero and Trumenba vaccines, respectively, whereas, 77.0% and 46.7% remained indeterminate. In conclusion, N. meningitidis isolates recovered in Taiwan between 2003 and 2020 were mostly highly diverse. Most IMD cases appeared sporadically and were caused by localized strains, although some patients were infected by recently introduced strains. cgMLST is a powerful tool for the rapid comparison of genetic relatedness among a large number of isolates. cgMLST profiling, based on 1,241 core genes, and strain tracking can be performed on the website of cgMLST@Taiwan (http://rdvd.cdc.gov.tw/cgMLST/). IMPORTANCE N. meningitidis can cause life-threatening invasive meningococcal disease (IMD), including meningitis and sepsis, resulting in a high CFR and long-term sequelae in survivors. Here, we report the demographic features of IMD in Taiwan over a 28-year period (1993 to 2020) and the genetic characteristics of N. meningitidis isolates recovered from patients with IMD over an 18-year period (2003 to 2020). We conducted a whole-genome sequence analysis to characterize the genetic features of the isolates and developed a cgMLST scheme for epidemiological investigation and strain tracking. The findings can be beneficial in understanding the epidemiology of IMD in Taiwan, the genetic characteristics of the bacterial strains, and the distribution of vaccine antigens for vaccine development and implementation.

Background: Escherichia coli is the most common cause of urinary tract infections (UTIs). It is widely accepted that uropathogenic E. coli (UPEC) mainly emerge from the distal gut microbiota. Identification of bacterial characteristics that are able to differentiate UPEC from fecal commensal strains will facilitate the development of novel strategies to detect and monitor the spread of UPEC., Methods: Fifty fecal commensal, 83 UTI-associated and 40 biliary tract infection (BTI)-associated E. coli isolates were analyzed. The NotI restriction patterns of chromosomal DNA in the isolates were determined by pulse-field gel electrophoresis. The phylogenetic types and the presence of 9 known virulence genes of each isolate were determined by PCR analyses. Additionally, the susceptibilities of the isolates to antibiotics were revealed. Then the associations of NotI resistance with UTI-associated isolates, phylotypes, and antibiotic resistance were assessed., Results: NotI resistance was correlated with UTI-associated isolates, compared to the fecal isolates. Consistently, NotI-resistant isolates harbored a greater number of virulence factors and mainly belonged to phylotype B2. Additionally NotI resistance was correlated with chloramphenicol resistance among the bacteria. Among the fecal, UTI-associated and BTI-associated groups, the distribution of NotI-resistant group B2 isolates was correlated with UTI-associated bacteria., Conclusion: NotI resistance alone is a potential marker for distinguishing fecal strains and UPEC, while the combination of NotI resistance and B2 phylogeny is a candidate marker to differentiate UPEC from fecal and other extraintestinal pathogenic E. coli. Additionally, NotI resistance may be valuable for assessing the potential of chloramphenicol resistance of E. coli., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or other association that might pose a conflict of interest., (Copyright © 2021. Published by Elsevier B.V.)

Objectives: A nosocomial salmonellosis outbreak caused by Salmonella enterica serovar Goldcoast occurred in a respiratory care ward (RCW) of a hospital in central Taiwan between December 24, 2020, and January 21, 2021. Ten isolates recovered from 10 RCW residents were resistant to extended-spectrum cephalosporins. The resistance mechanism needs to be investigated., Methods: Whole-genome sequencing and antimicrobial susceptibility testing were conducted to determine the genetic resistance determinants and the phenotypic resistance in the isolates., Results: Each of the 10 outbreak isolates harbored an IncHI2 plasmid that carried 15 antimicrobial resistance genes aac(3)-IId, aadA22, aph(3')-Ia, aph(6)-Id, arr-2, bla CTX-M-55 , bla LAP-2 , bla TEM-1 , dfrA14, floR, lnu(F), qnrS13, sul2, sul3, tet(A), an efflux pump regulatory gene ramAp and an IncL plasmid carried a bla OXA-48 . The outbreak strains were expected to be resistant to numerous antimicrobials, including aminoglycosides, b-lactams /inhibitors, tetracycline, rifamycin, lincosamide, sulfonamides, trimethoprim, phenicols, fluoroquinolones, and carbapenems. Two outbreak isolates displayed higher minimum inhibitory concentrations than the other eight isolates to cefmetazole and carbapenems, which was linked to a deficiency of a major facilitator superfamily transporter in the two isolates., Conclusion: The carbapenem-resistant outbreak strains could have been derived from extensively drug-resistant S. enterica Goldcoast strains, which have been a major pathogen in Taiwan since 2018, through the acquisition of a bla OXA-48 -carrying plasmid. Special efforts are needed in Taiwan to monitor the spread of extremely resistant strains., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background/purpose: Salmonella Panama was considered an invasive non-typhoidal Salmonella (iNTS) serovar. Comprehensive clinical, microbiological, and genomic studies on S. Panama are scarce. We aimed to characterize the clinical and microbiological characteristics of S. Panama infection. Virulence mechanism of S. Panama and other iNTS serovars were also examined., Methods: Based on data from the longitudinal surveillance system for Salmonella deployed in Taiwan since 2004, a case-control study was undertaken to evaluate clinical characteristics of S. Panama infection during an outbreak in 2015-2016. Cellular experiments were conducted to compare pathogenicity of S. Panama and other iNTS with S. Typhimurium., Results: Most patients (41/44, 93.2%) infected by S. Panama were <5 years old (median, 1.3 years). The case-control study showed that 28 out of the 41 (68.3%) manifested as bacteremia, compared to S. Typhimurium (11.1%). Patients infected by S. Panama had longer durations of fever (P = 0.005) and hospitalization (P < 0.001). Genomic analyses split the isolates into three clades: two clones caused the outbreak, whereas another one accounted for the sporadic infections before 2015. Cellular experiments revealed that S. Panama and other iNTS serovars showed higher monolayer penetration and intracellular survival within macrophages, compared to S. Typhimurium., Conclusion: This study confirmed that S. Panama is a clinically invasive serovar. Different iNTS serovars express common virulence phenotypes, but they may acquire invasiveness through distinct expression or combinations of virulence genes., Competing Interests: Declaration of competing interest The authors have no conflicts of interest relevant to this article., (Copyright © 2021. Published by Elsevier B.V.)

Background: Cholera, a rapidly dehydrating diarrheal disease caused by toxigenic Vibrio cholerae, is a leading cause of morbidity and mortality in some regions of the world. Core genome multilocus sequence typing (cgMLST) is a promising approach in generating genetic fingerprints from whole-genome sequencing (WGS) data for strain comparison among laboratories., Methods: We constructed a V. cholerae core gene allele database using an in-house developed computational pipeline, a database with cgMLST profiles converted from genomic sequences from the National Center for Biotechnology Information, and built a REST-based web accessible via the Internet., Results: We built a web service platform-cgMLST@Taiwan and installed a V. cholerae allele database, a cgMLST profile database, and computational tools for generating V. cholerae cgMLST profiles (based on 3,017 core genes), performing rapid global strain tracking, and clustering analysis of cgMLST profiles. This web-based platform provides services to researchers, public health microbiologists, and physicians who use WGS data for the investigation of cholera outbreaks and tracking of V. cholerae strain transmission across countries and geographic regions. The cgMLST@Taiwan is accessible at http://rdvd.cdc.gov.tw/cgMLST., (Copyright © 2021. Published by Elsevier B.V.)

Campylobacter coli and Campylobacter Jejuni are highly resistant to most therapeutic antimicrobials in Taiwan; rapid diagnostics of resistance in bacterial isolates is crucial for the treatment of campylobacteriosis. We characterized 219 (40 C. coli and 179 C. jejuni) isolates recovered from humans from 2016 to 2019 using whole-genome sequencing to investigate the genetic diversity among isolates and the genetic resistance determinants associated with antimicrobial resistance. Susceptibility testing with 8 antimicrobials was conducted to assess the concordance between phenotypic resistance and genetic determinants. The conventional and core genome multilocus sequence typing analysis revealed diverse clonality among the isolates. Mutations in gyrA (T86I, D90N), rpsL (K43R, K88R), and 23S rRNA (A2075G) were found in 91.8%, 3.2%, and 6.4% of the isolates, respectively. The horizontally transferable resistance genes ant(6)-I , aad9 , aph(3')-IIIa , aph(2″) , bla OXA , catA / fexA , cfr (C), erm (B), lnu , sat4 , and tet were identified in 24.2%, 21.5%, 33.3%, 11.9%, 96.3%, 10.0%, 0.9%, 6.8%, 3.2%, 13.2%, and 96.3%, respectively. High-level resistance to 8 antimicrobials in isolates was 100% predictable by the known resistance determinants, whereas low-level resistance to azithromycin, clindamycin, nalidixic acid, ciprofloxacin, and florfenicol in isolates was associated with sequence variations in CmeA and CmeB of the CmeABC efflux pump. Resistance-enhancing CmeB variants were identified in 62.1% (136/219) of isolates. In conclusion, an extremely high proportion of C. coli (100%) and C. jejuni (88.3%) were multidrug-resistant, and a high proportion (62.5%) of C. coli isolates were resistant to azithromycin, erythromycin, and clindamycin, which would complicate the treatment of invasive campylobacteriosis in this country.

In investigating the epidemiological trends of Salmonella enterica serovar Goldcoast, we previously identified several closely related strains with different MICs to azithromycin and quinolones. Genome sequencing and comparison of two very similar multidrug-resistant (MDR) strains, R18.0877 and R18.1656, has led to the identification of an extra plasmid-borne ramA gene, ramAp , on the large IncHI2 plasmid carried by R18.0877. The ramAp gene is located in a 953-bp region on the plasmid, which is identical to that of the Klebsiella quasipneumoniae chromosomal ramA loci. A truncated IS Ecp1 located at the adjacent upstream area of the putative regulatory region of ramAp may likely contribute to its mobilization and expression. Introducing the ramAp gene and the truncated IS Ecp1 into Escherichia coli has resulted in elevated expression of efflux pump genes and elevated MICs to chloramphenicol, azithromycin, nalidixic acid, ciprofloxacin, sulfamethoxazole, trimethoprim, tetracycline, and tigecycline. The ramAp is an extra efflux pump activator gene that potentially could be transmitted with the IncHI2 plasmid among bacteria. It is plausible that, with high interspecific conservation, the plasmid-encoded regulator reduces drug susceptibility by activating existing efflux pump systems of the host and thus can be regarded as a new type of auxiliary antimicrobial resistance determinant. Sequences of similar plasmids were found worldwide. Its impact on the emergence of antimicrobial resistance among bacterial pathogens is worrisome.

Competing Interests: Competing interests: The BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare the following other interests: none. Further details of The BMJ policy on financial interests are here: https://www.bmj.com/about-bmj/resources-authors/forms-policies-and-checklists/declaration-competing-interests

Objective: To compare Pneumocystis jirovecii pneumonia (PJP) risk between patients with autoimmune rheumatic diseases (ARD) and the general population METHODS: We identified patients with ARD recorded in the National Health Insurance Research Database of Taiwan from 2002 to 2015 and randomly selected a comparison cohort from the general population matched for age and sex. We analyzed PJP risk stratified by sex, age, comorbidities, and medications using Cox proportional hazard model., Results: We enrolled 103,117 patients with ARD. PJP risk significantly increased in patients with any ARD and with each individual ARD like rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Sjogren's syndrome (SjS), polymyositis and dermatomyositis (PM/DM), systemic sclerosis (SSc), and systemic vasculitis. Patients with PM/DM showed prominent risk with incidence rate of 12.47/100,000 patient year (95% confidence interval (CI), 32.16-86.70). In a time-dependent Cox proportional hazard model with comorbidities and medications as covariates, PM/DM, SSc, SLE, and SjS significantly increased adjusted hazard ratios (aHR) of 5.40, 5.12, 4.09, and 3.64, respectively (95% CI of 2.82-10.35, 2.16-12.13, 2.41-6.95, and 2.06-6.42, respectively). AHR after adjusting for male sex, cancer, human immunodeficiency virus infection (HIV), and interstitial lung disease also significantly increased. Use of daily oral steroid dose of >10 mg conferred the highest risk followed by mycophenolate. Use of injected steroids, cyclophosphamide, biological agents, methotrexate, and cyclosporine conferred a significantly higher risk., Conclusion: Underlying ARD significantly predisposes patients to PJP, with PM/DM posing the highest threat. In addition to underlying disease, comorbidities and concomitant immunosuppressants are major risks. The strongest risk is recent daily steroid dose of >10 mg. Mycophenolate seems to be a more prominent risk factor than cyclophosphamide. Key Points • Autoimmune rheumatic diseases (ARD) significantly increased the overall risk of PJP, and so did each individual ARD. • Use of steroids, mycophenolate, cyclophosphamide, biological agents, methotrexate, and cyclosporine all significantly increased risk of PJP. • Male, elderly, malignancy, HIV, and interstitial lung disease are also related to increased risk of PJP. • Underlying ARD, comorbidities, and use of immunosuppressant should all be considered in determining the overall risk of PJP., (© 2021. International League of Associations for Rheumatology (ILAR).)

With the reduction in the cost of next-generation sequencing, whole-genome sequencing (WGS)-based methods such as core-genome multilocus sequence type (cgMLST) have been widely used. However, gene-based methods are required to assemble raw reads to contigs, thus possibly introducing errors into assemblies. Because the robustness of cgMLST depends on the quality of assemblies, the results of WGS should be assessed (from sequencing to assembly). In this study, we investigated the robustness of different read lengths, read depths, and assemblers in recovering genes from reference genomes. Different combinations of read lengths and read depths were simulated from the complete genomes of three common food-borne pathogens: Escherichia coli , Listeria monocytogenes , and Salmonella enterica . We found that the quality of assemblies was mainly affected by read depth, irrespective of the assembler used. In addition, we suggest several cutoff values for future cgMLST experiments. Furthermore, we recommend the combinations of read lengths, read depths, and assemblers that can result in a higher cost/performance ratio for cgMLST., Competing Interests: The authors declare there are no competing interests., (©2021 Liu et al.)

The first imported case of XDR typhoid fever in Taiwan contracted with a bacterial strain, which was most closely related to the bla CTX-M-15 -carrying strains linked to Pakistan. Meropenem, in combination with an antimicrobial with intracellular activity against Salmonella, should be used for the treatment of XDR typhoid fever., Competing Interests: Declaration of Competing Interest The authors have no conflict of interest to be declared., (Copyright © 2020. Published by Elsevier B.V.)

Klebsiella pneumoniae resides in the gastrointestinal (GI) microbiota of humans and animals. To characterize the population dynamics of GI-colonizing K. pneumoniae, we examined the clonality of K. pneumoniae isolates, which were longitudinally collected from the fecal samplings of a healthy married couple and their pet animals during Sep. 2015 to Oct. 2016. As revealed by XbaI-PFGE analysis, the K. pneumoniae populations detected in the male owner and in one of the dogs, consisted of clonally diverse K. pneumoniae isolates; whereas, a dominant clone persisted in the GI tract of the female owner who was prone to chronic diarrhea. Whole-genome sequencing analysis of a representative strain of this pathobiont clone revealed a sequence type (ST) 29 lineage with the carriage of KL54 cps locus and a 192,603 bp IncHIB-type virulence plasmid. After probiotics intervention, the pathobiont K. pneumoniae diminished. The vacant niche was transiently occupied by other clones of K. pneumoniae, one of which was also present in the male owner. Besides the dog, the fecal carriage of K. pneumoniae was also detected in a pet turtle. This turtle isolate was resistant to multiple antimicrobials, including carbapenems. Possible transmission of drug-resistant K. pneumoniae through human-pet bonds warrants our attention., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Most publicly available genomes of Salmonella enterica are from human disease in the US and the UK, or from domesticated animals in the US. Methods: Here we describe a historical collection of 10,000 strains isolated between 1891-2010 in 73 different countries. They encompass a broad range of sources, ranging from rivers through reptiles to the diversity of all S. enterica isolated on the island of Ireland between 2000 and 2005. Genomic DNA was isolated, and sequenced by Illumina short read sequencing. Results: The short reads are publicly available in the Short Reads Archive. They were also uploaded to EnteroBase, which assembled and annotated draft genomes. 9769 draft genomes which passed quality control were genotyped with multiple levels of multilocus sequence typing, and used to predict serovars. Genomes were assigned to hierarchical clusters on the basis of numbers of pair-wise allelic differences in core genes, which were mapped to genetic Lineages within phylogenetic trees. Conclusions: The University of Warwick/University College Cork (UoWUCC) project greatly extends the geographic sources, dates and core genomic diversity of publicly available S. enterica genomes. We illustrate these features by an overview of core genomic Lineages within 33,000 publicly available Salmonella genomes whose strains were isolated before 2011. We also present detailed examinations of HC400, HC900 and HC2000 hierarchical clusters within exemplar Lineages, including serovars Typhimurium, Enteritidis and Mbandaka. These analyses confirm the polyphyletic nature of multiple serovars while showing that discrete clusters with geographical specificity can be reliably recognized by hierarchical clustering approaches. The results also demonstrate that the genomes sequenced here provide an important counterbalance to the sampling bias which is so dominant in current genomic sequencing., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Achtman M et al.)

Apart from aging process, adult intervertebral disc (IVD) undergoes various degenerative processes. However, the nicotine has not been well identified as a contributing etiology. According to a few studies, nicotine ingestion through smoking, air or clothing may significantly accumulate in active as well as passive smokers. Since nicotine has been demonstrated to adversely impact various physiological processes, such as sympathetic nervous system, leading to impaired vasculature and cellular apoptosis, we aimed to investigate whether nicotine could induce IVD degeneration. In particular, we evaluated dose-dependent impact of nicotine in vitro to simulate its chronic accumulation, which was later treated by platelet-derived biomaterials (PDB). Further, during in vivo studies, mice were subcutaneously administered with nicotine to examine IVD-associated pathologic changes. The results revealed that nicotine could significantly reduce chondrocytes and chondrogenic indicators (Sox, Col II and aggrecan). Mice with nicotine treatment also exhibited malformed IVD structure with decreased Col II as well as proteoglycans, which was significantly increased after PDB administration for 4 weeks. Mechanistically, PDB significantly restored the levels of IGF-1 signaling proteins, particularly pIGF-1 R, pAKT, and IRS-1, modulating ECM synthesis by chondrocytes. Conclusively, the PDB impart reparative and tissue regenerative processes by inhibiting nicotine-initiated IVD degeneration, through regulating IGF-1/AKT/IRS-1 signaling axis.

Sequence type (ST) 11 is one of the major lineages of carbapenem-resistant Klebsiella pneumoniae (CRKP). Although the gastrointestinal (GI) carriage of CRKP predisposes individuals to subsequent infections, little is known for its impact on gut homeostasis. In this study, we investigated the association between ST11 CRKP colonization and colorectal cancer (CRC). Two ST11 CRKP, KPC160111 (KL47) and KPC160132 (KL64), were selected as the representative strains. We used azoxymethane (AOM) and dextran sodium sulfate (DSS) to initiate a colitis-associated CRC model. Both strains established prolonged colonization in the GI tract of the AOM-DSS-treated BALB/c mice and aggravated gut dysbiosis. Under this AOM-DSS-induced setting, ST11 K. pneumoniae colonization significantly promoted the growth and progression of colorectal adenomas to high-grade dysplasia. Numerous crypts were formed inside the enlarged adenomas, in which CD163 + tumor-associated macrophages accumulated. Similarly, ST11 K. pneumoniae also increased the population size of the CD163 + macrophages with the M2 phenotype in the peritoneal cavity of LPS-primed BALB/c mice. When applied to RAW264.7 cells, ST11 K. pneumoniae polarized the macrophages toward an M2 phenotype through the inhibition of IKK-NFκB and the activation of STAT6-KLF4-IL-10. Through the M2-skewing ability, ST11 K. pneumoniae promoted the accumulation of CD163 + macrophages in the adenomatous crypts to create an immunosuppressive niche, which not only accommodated the extended stay for its own sake but also deteriorated colorectal tumorigenesis.

The degree of surveillance data and control strategies for invasive meningococcal disease (IMD) varies across the Asia-Pacific region. IMD cases are often reported throughout the region, but the disease is not notifiable in some countries, including Myanmar, Bangladesh and Malaysia. Although there remains a paucity of data from many countries, specific nations have introduced additional surveillance measures. The incidence of IMD is low and similar across the represented countries (<0.2 cases per 100,000 persons per year), with the predominant serogroups of Neisseria meningitidis being B, W and Y, although serogroups A and X are present in some areas. Resistance to ciprofloxacin is also of concern, with the close monitoring of antibiotic-resistant clonal complexes (e.g., cc4821) being a priority. Meningococcal vaccination is only included in a few National Immunization Programs, but is recommended for high-risk groups, including travellers (such as pilgrims) and people with complement deficiencies or human immunodeficiency virus (HIV). Both polysaccharide and conjugate vaccines form part of recommendations. However, cost and misconceptions remain limiting factors in vaccine uptake, despite conjugate vaccines preventing the acquisition of carriage., (Crown Copyright © 2020. Published by Elsevier Ltd. All rights reserved.)

Background: Most publicly available genomes of Salmonella enterica are from human disease in the US and the UK, or from domesticated animals in the US. Methods: Here we describe a historical collection of 10,000 strains isolated between 1891-2010 in 73 different countries. They encompass a broad range of sources, ranging from rivers through reptiles to the diversity of all S. enterica isolated on the island of Ireland between 2000 and 2005. Genomic DNA was isolated, and sequenced by Illumina short read sequencing. Results: The short reads are publicly available in the Short Reads Archive. They were also uploaded to EnteroBase, which assembled and annotated draft genomes. 9769 draft genomes which passed quality control were genotyped with multiple levels of multilocus sequence typing, and used to predict serovars. Genomes were assigned to hierarchical clusters on the basis of numbers of pair-wise allelic differences in core genes, which were mapped to genetic Lineages within phylogenetic trees. Conclusions: The University of Warwick/University College Cork (UoWUCC) project greatly extends the geographic sources, dates and core genomic diversity of publicly available S. enterica genomes. We illustrate these features by an overview of core genomic Lineages within 33,000 publicly available Salmonella genomes whose strains were isolated before 2011. We also present detailed examinations of HC400, HC900 and HC2000 hierarchical clusters within exemplar Lineages, including serovars Typhimurium, Enteritidis and Mbandaka. These analyses confirm the polyphyletic nature of multiple serovars while showing that discrete clusters with geographical specificity can be reliably recognized by hierarchical clustering approaches. The results also demonstrate that the genomes sequenced here provide an important counterbalance to the sampling bias which is so dominant in current genomic sequencing., Competing Interests: No competing interests were disclosed., (Copyright: © 2020 Achtman M et al.)

Salmonella is a leading cause of foodborne outbreaks in Taiwan. On 27 April 2018, a salmonellosis outbreak among customers of a restaurant was reported to the Taiwan CDC. We investigated the outbreak to identify infection sources and prevent further transmission. We interviewed ill customers and their dining companions. We conducted a case-control study to identify foods associated with the illness. Case-patients were those who had diarrhoea within 72 h after eating at the restaurant during 16-27 April 2018. Specimens, food samples and environmental samples were collected and tested for enteric pathogens. Salmonella isolates were analysed with pulse-field gel electrophoresis and whole-genome sequencing. We inspected the restaurant sanitation and reviewed kitchen surveillance camera recordings. We identified 47 case-patients, including one decedent. Compared with 44 controls, case-patients were more likely to have had a French toast sandwich (OR: 102.4; 95% CI: 18.7-952.3). Salmonella Enteritidis isolates from 16 case-patients shared an indistinguishable genotype. Camera recordings revealed eggshell contamination, long holding time at room temperature and use of leftovers during implicated food preparation. Recommendations for restaurant egg-containing food preparation are to use pasteurised egg products and ensure a high enough cooking temperature and long enough cooking time to prevent Salmonella contamination.

This study focused on an iron phthalocyanine compound with aligned CNTs on the surface of a carbon felt electrode (FePc/CNT/C) to enhance the bio-electro-Fenton microbial fuel cell system cathodes reaction rate of hydrogen peroxide and the electrical plate. Experiments of polarization curves and power density, decolorization of Reactive Black 5 (RB5), and scanning electron microscopy (SEM) measured the characteristics of the cathode plate. FePc/CNT/C presented better electrical properties (open-circuit voltage, maximum current density, and maximum power density) than that of CNT/C and C, as FePc is a catalyst and its planar structure could easily adhere to CNT to enhance the reduction reaction at the cathode and provide higher specific surface area. The optimal decolorization of RB5 dye, as achieved with the FePc/CNT/C electrode, was 61.79% among the three cathode electrodes in the bio-electro-Fenton microbial fuel cell system, and the maximum number of hydroxyl radicals was generated for the cathode electrode of FePc/CNT/C. These results suggest that the bio-electro-Fenton microbial fuel cell system could be applied as an energy-saving and efficient approach for dye-containing wastewater treatment.

Objectives: Epidemic spread of OXA-48-producing Klebsiella pneumoniae, mainly mediated by the transmission of a blaOXA-48-carrying plasmid, has threatened global health during the last decade. Since its introduction to Taiwan in 2013, OXA-48 has become the second most common carbapenemase. We described the transmission and evolution of an OXA-producing K. pneumoniae clone in a single hospital., Methods: Twenty-two OXA-48 K. pneumoniae were isolated between October 2013 and December 2015. Comparative genomic analysis was performed based on the WGS data generated with Illumina and MinION techniques., Results: Seventeen of the 22 OXA-48 K. pneumoniae that belonged to ST11, with the same capsular genotype, KL64, and differed from each other by seven or fewer SNPs, were considered outbreak strains. Eight of the 17 outbreak strains harboured a 65499 bp blaOXA-48-carrying IncL plasmid (called pOXA48). pOXA48 was absent from the remaining nine strains. Instead, a 24.9 kb blaOXA-48-carrying plasmid fragment was integrated into a prophage region of their chromosomes. Transmission routes of the ST11&#95;KL64 K. pneumoniae sublineages, which carried either pOXA48 or chromosomally integrated blaOXA-48, were reconstructed., Conclusions: Clonal expansion of ST11&#95;KL64 sublineages contributed to the nosocomial outbreak of OXA-48 K. pneumoniae. The chromosome-borne blaOXA-48 lineage emerged during a 2 year period in a single hospital. Dissemination of OXA-48, which is vertically transmitted in K. pneumoniae even in the absence of selective pressure from antimicrobials, deserves public health attention., (© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

We investigated the epidemiology of cholera in Taiwan during 2002-2018. Vibrio cholerae sequence type (ST) 75 clone emerged in 2009 and has since become more prevalent than the ST69 clone from a previous pandemic. Closely related ST75 strains have emerged in 4 countries and may now be widespread in Asia.

Salmonella enterica serovar Goldcoast infection was rare in Taiwan; it was not detected in routine surveillance from 2004 to 2013. This serovar was first identified in 2014, but the frequency of infection remained low until 2017. From 2014 to 2016, all but one isolate was pan-susceptible. S Goldcoast infections abruptly increased in 2018, and all isolates were multidrug-resistant (MDR). All MDR isolates harbored an IncHI2 plasmid, and the majority carried 14 antimicrobial resistance genes, aac(3)-IId , aadA22 , aph(3')-Ia , aph(6)-Id , bla TEM-1B , bla CTX-M-55 , lnu (F), floR , qnrS13 , arr-2 , sul2 , sul3 , tet (A), and dfrA14. S Goldcoast strains recovered in Taiwan and 96 of 99 strains from Germany, the Netherlands, the United Kingdom, and the United States belonged to sequence type 358 (ST358). Whole-genome single-nucleotide polymorphism and core genome multilocus sequence type analyses revealed that all strains of the ST358 clone shared a high degree of genetic relatedness. The present study highlighted that a dramatic increase in S Goldcoast infections followed the emergence of MDR strains and indicated that a genetically closely related S Goldcoast ST358 clone may have widespread significance internationally., (Copyright © 2019 American Society for Microbiology.)

Salmonella Typhimurium and S. Stanley are the most prevalent serogroup B serovars to infect humans in Taiwan. The aim was to determine possible factors to influence the prevalence between S. Typhimurium and S. Stanley. Genotypes were determined by pulsed field gel electrophoresis (PFGE) analysis and the intracellular survival, phagocytosis, reactive oxygen species (ROS) production of human monocyte THP-1 cell and tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), and IL-1βexpression in peripheral blood CD14 + cells after infection were analyzed. 182 S. Stanley was clonal disseminated with main pulsotypes 2 from 2004 to 2007. Overall S. Typhimurium evolved more genotypes, while S. Stanley conserved in genotypes. Human blood CD14 + monocytes expressed TNF-α, IL-6 and IL-1β differently among serovars and bacterial conditions (live vs. killed). Live S. Stanley and S. Typhimurium suppressed the TNF-α and IL-6 expression compared to killed bacteria. However, live S. Typhimurium stimulated more IL-1β expression than the killed bacteria, but S. Stanley expressed similar IL-1β levels in both conditions. Furthermore, S. Stanley and S. Typhimurium differed in intracellular survival in the THP-1 cells, an early decrease for S. Stanley, not for S. Typhimurium. Additionally, higher reactive oxygen species (ROS) production in THP-1 cells was found agsinst S. Stanley infection, not found in S. Typhimurium. However, some isolates of S. Stanley could recover from early loss to become more in the monocytes than S. Typhimurium. Difference in phagocytized number, intracellular survival, ROS production and IL-1β expression may contribute to prevalence different between two serovars., (Copyright © 2018. Published by Elsevier Ltd.)

The dynamics of the exciton generated by photoexcitation of a regioregular poly(3-hexylthiophene) (P3HT) polymer dispersed in a poly(methyl methacrylate) (PMMA) matrix was examined using electro-photoluminescence (E-PL) spectroscopy, where electric field effects on the photoluminescence (PL) spectra were measured. The quadratic electric-field effect was investigated using the modulation technique, with field-induced changes in the PL intensity monitored at the second harmonic of the modulation frequency of the applied electric field. Absorption and PL spectra indicated the formation of both ordered crystalline aggregates and amorphous regions of P3HT polymer chains. Although previous studies of electric field effects on π-conjugated polymers have generally shown that the PL intensity is decreased by electric fields, we report that the PL intensity of P3HT and PL lifetime increased with the quadratic electric-field effect. The magnitude of the change in PL intensity was quantitatively explained in terms of the field-induced decrease in the nonradiative decay rate constants of the exciton. We proposed that a delayed PL, originating from charge carrier recombination, was enhanced in the presence of electric fields. The rate constant of the downhill relaxation process of the exciton, which originated from the relaxation in distributed energy levels due to an inherent energetic disorder in P3HT aggregates, was implied to decrease in the presence of electric fields. The radiative decay rate constant and PL quantum yield of P3HT dissolved in solution, which were evaluated from the molar extinction coefficient and the PL lifetime, were compared with those of P3HT dispersed in a PMMA matrix.

Objectives: Outbreaks of shigellosis among men who have sex with men (MSM) have been reported since the late 1990s. HIV infection is an important risk factor. Since 2014, the global shigellosis epidemic has intensified. Whether chemsex (the use of crystal methamphetamine, γ-hydroxybutyrate or mephedrone to enhance sex) is a new risk factor has not been previously examined., Methods: We conducted a population-based, case-control study in Taiwan. Acute shigellosis cases diagnosed during the 2015 outbreak among MSM living with HIV were compared with those without shigellosis. CD4 + counts, plasma viral load (pVL), gonorrhoea, syphilis and amoebiasis records were obtained from the Notifiable Disease Surveillance System database. We invited cases/controls to provide information on illicit drug use and sexual behaviours, using a structured questionnaire., Results: Seventy-five shigellosis cases were compared with 225 controls. High pVL (>100 000 copies/mL; adjusted OR (aOR): 4.9, 95% CI 1.4 to 16.9), gonorrhoea (aOR: 29.4, 95% CI 2.3 to 340.2) and syphilis (aOR: 4.3, 95% CI 1.6 to 11.6) were independent risk factors of shigellosis. Twenty shigellosis cases and 59 controls completed the questionnaire. Oral-to-anal sex (aOR: 15.5, 95% CI 3.6 to 66.7), chemsex (aOR: 5.6, 95% CI 1.4 to 22.7) and poppers use (aOR: 10.9, 95% CI 1.9 to 64.2) within 12 months were independent behavioural risk factors of shigellosis., Conclusions: Chemsex is a new risk factor for shigellosis among MSM living with HIV, as identified in the 2015-2016 outbreak. Additional risk factors include poppers use, sexual risk behaviours and high pVL. Further studies on chemsex among MSM, which is a rising public health concern, are urgently required., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2019. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

In 2011, a Salmonella enterica serovar Anatum clone emerged in Taiwan. During 2016-2017, infections increased dramatically, strongly associated with emergence and spread of multidrug-resistant strains with a plasmid carrying 11 resistance genes, including bla DHA-1 . Because these resistant strains infect humans and food animals, control measures are urgently needed.

Osteoarthritis (OA) poses a major clinical challenges owing to limited regenerative ability of diseased or traumatized chondrocytes in articular cartilage. Previous studies have determined the individual therapeutic efficacies of hyaluronic acid (HA) and platelet-rich plasma (PRP) on OA; however, the underlying mechanism is still lacking. Therefore, we investigated mechanistic approach of HA+PRP therapy on chondrocyte apoptosis in IL-1β+TNF-α (I+T) treated in vitro OA model, in addition to in vivo anterior cruciate ligament transection-OA mice model. MTT assay showed an enhanced chondrocyte proliferation and viability in HA+PRP-treated group, compared to I+T, I+T/HA, I+T/PRP, I+T/HA+PRP groups. Further, HA+PRP also significantly suppressed ROS, apoptotic cleaved caspase-3 and PARP, p53 and p21 and MMP-1; whereas, cell cycle modulatory proteins including p-ERK, cyclin B1, D1, and E2 were upregulated. The sub-G1 population and TUNEL assay confirmed the higher abundance of healthy chondrocytes in HA+PRP group. A significantly decreased ARS staining in HA+PRP group was also noted, indicating reduced cartilaginous matrix mineralization compared to other groups. Conclusively, compared to HA or PRP, the combined HA+PRP might be a promising therapy for articular cartilage regeneration in osteoarthritic pathology, possibly via augmented anti-inflammatory, anti-oxidative chondrocyte proliferation and inhibited MMP-1 activity and matrix calcification.

Objectives: The global spread of carbapenem-resistant Klebsiella pneumoniae (CR-Kp) has become a massive threat to human health. We investigated the clonal relatedness of CR-Kp strains in central Taiwan., Methods: CR-Kp strains were prospectively collected from inpatients referred to Chung Shan Medical University Hospital (CSMUH) during September 2011 to December 2015. The presence of carbapenemase genes, including bla KPC-2 , bla VIM-1 , bla NDM-1 , and bla OXA-48 , was analysed with polymerase chain reaction (PCR) and sequence determination. Clonal relatedness was determined by pulse-field gel electrophoresis and multilocus sequence typing. Capsule synthesis loci were typed based on the variation of the wzi gene., Results: A total of 174 CR-Kp strains were collected. KPC-2 and OXA-48 were present in 63 (36.2%) and 22 (12.6%) CR-Kp strains, respectively. Two strains isolated in 2014 coproduced KPC-2 and OXA-48. Nearly all (98%) carbapenemase-producing K. pneumoniae strains belonged to the ST11 clone and could be further grouped into distinct sub-lineages. Intriguingly, the first sub-lineage, designated ST11-Clade I, contained all KPC-2 strains; OXA-48 strains were mostly included in the second sub-lineage, ST11-Clade II. Furthermore, a variation on the capsule synthesis loci was detected between these two sub-lineages: KL-47 was assigned to ST11-Clade I, whereas KL-64 or KL-9 were the main types for the ST11-Clade II strains., Conclusions: Clonal expansion of ST11 was responsible for the dissemination of carbapenemase-producing K. pneumoniae. Although KPC-2 still predominates, OXA-48 has emerged rapidly. Co-existence of KPC-2 and OXA-48 in two ST11-Clade I K. pneumoniae highlights the urgency to unravel mechanisms that contribute to this highly transmissible lineage., (Copyright © 2018 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.)

[This corrects the article DOI: 10.18632/oncotarget.21315.].

Salmonella is one of the most common pathogens of waterborne and foodborne disease-causing pathogens. In this study, we collected 172 surface water samples from Puzih River and Kaoping River between the years 2010 and 2011. Salmonella was detected in 31.7% (32/101) and 42.2% (30/71) of the samples from the two rivers, respectively. From these positive samples, 44 Salmonella isolates were obtained from these positive samples and were characterized using serotyping and pulsed-field gel electrophoresis (PFGE) genotyping. The isolates were found with 17 serovars and 32 PFGE patterns. Salmonella enterica Newport, Bareilly, Kedougou, Albany and subspecies IIIb 50:k:z were the five most common serovars in aquatic environmental Salmonella isolates. In addition, of the total clinical samples from Chiayi and Kaohsiung, 33.7% (60/178) Newport serovars were isolated. After conducting categorical analysis, we found that the serovar Newport was not uniformly distributed cross the cities. The serovar Newport was over-represented (p<0.001) among human isolates in Chiayi and Kaohsiung. To investigate the association between Salmonella isolates from aquatic environment and human samples, we compared the environmental PFGE patterns of the test samples with those of 2438 clinical isolates, obtained from 51 hospitals across the country between 2010 and 2011. Of the 32 PFGE genotypes of environmental isolates, 8 genotypes were identical to those of clinical samples. Serovar Newport isolates with PFGE patterns SNX.119 and SNX.183 obtained from Puzih River samples were also identified in human samples at a local hospital. These suggest that there is a link between environmental and human clinical Salmonella. Identification of Salmonella serovars and genotypes present in surface water provides an indication of the specific S. enterica serovars and genotypes present in humans. This is the first study to investigate the Salmonella serovars and genotypes present in aquatic environment and humans in Taiwan., (Copyright © 2017 Elsevier B.V. All rights reserved.)