Chromosome-Borne CTX-M-65 Extended-Spectrum ß-Lactamase-Producing Salmonella enterica Serovar Infantis, Taiwan.

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: blaCTX-M-65, tet(A), sul1, and aadA1.

Antimicrobial Resistance in Campylobacter coli and Campylobacter jejuni from Human Campylobacteriosis in Taiwan, 2016 to 2019.

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″), blaOXA, 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.

Emergence of Multidrug-Resistant Salmonella enterica Serovar Goldcoast Strains in Taiwan and International Spread of the ST358 Clone.

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, blaTEM-1B, blaCTX-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.

Antimicrobial resistance and genetic relatedness among Campylobacter coli and Campylobacter jejuni from humans and retail chicken meat in Taiwan.

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.

Epidemiological trends in serotypes distribution and antimicrobial resistance in Salmonella from humans in Taiwan, 2004-2022.

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.

Risk factors for and prevalence of clonorchiasis in Miaoli County, Taiwan.

The objective of this study was to investigate the risk factors for and prevalence of clonorchiasis in Miaoli County, Taiwan. In 2009, 6,929 subjects were randomly selected in Miaoli County and given a questionnaire to fill out regarding risk factors for clonorchiasis; the response rate was 69%. Stool sample was obtained from each participant who filled out the questionnaire and examined using the merthiolate-iodine-formaldehyde concentration (MIFC) technique to determine the presence and concentration of Clonorchis sinensis eggs. Fifty-one subjects gave a history of clonorchiasis (prevalence rate 0.7%). Seven stool samples were positive for C. sinensis (prevalence rate 0.1%). Shihtan Township (5.0%) in Miaoli County had the highest prevalence of clonorchiasis. Using logistic regression, we found people who often fished (OR: 3.65, p=0.013) or who had a family member with a history of clonorchiasis (OR: 18.7, p<0.001) were more likely to have it. We also found tourists who traveled to China and ate fish there (OR: 2.46, p=0.105) or who owned a fish pond (OR: 1.93, p=0.128) were more likely to get clonorchiasis. The prevalence of clonorchiasis in Miaoli County was relatively low, which can be explained by good sanitation and personal hygiene. The Public Health Department of Taiwan should warn Taiwanese travelers about high risk areas for contracting clonorchis infection and encourage these travelers to avoid going fishing or eating raw fish in high risk areas.

Epidemiological trends and antimicrobial resistance in Salmonella enterica serovar Typhimurium clones in Taiwan between 2004 and 2019.

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_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_2, 41, 305, and 310) exhibited multiple resistance in 86.5% to 96.1% of isolates. HC100_305 and HC100_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), blaCMY-2, and blaDHA-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.

Methamphetamine enhances caveolar transport of therapeutic agents across the rodent blood-brain barrier.

The blood-brain barrier (BBB) restricts clinically relevant accumulation of many therapeutics in the CNS. Low-dose methamphetamine (METH) induces fluid-phase transcytosis across BBB endothelial cells in vitro and could be used to enhance CNS drug delivery. Here, we show that low-dose METH induces significant BBB leakage in rodents ex vivo and in vivo. Notably, METH leaves tight junctions intact and induces transient leakage via caveolar transport, which is suppressed at 4°C and in caveolin-1 (CAV1) knockout mice. METH enhances brain penetration of both small therapeutic molecules, such as doxorubicin (DOX), and large proteins. Lastly, METH improves the therapeutic efficacy of DOX in a mouse model of glioblastoma, as measured by a 25% increase in median survival time and a significant reduction in satellite lesions. Collectively, our data indicate that caveolar transport at the adult BBB is agonist inducible and that METH can enhance drug delivery to the CNS.

Genomic Surveillance of Listeria monocytogenes in Taiwan, 2014 to 2019.

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.

Astragalus membranaceus-Derived Anti-Programmed Death-1 Monoclonal Antibodies with Immunomodulatory Therapeutic Effects against Tumors.

Astragalus membranaceus polysaccharide (APS) components are main ingredients of TCM and have proven efficacy to activate T cells and B cells, enhancing immunity in humans. In this study, elevated cytokine and anti-PD-1 antibody titers were found in mice after immunization with APS. Therefore, phage-display technology was utilized to isolate specific anti-programmed death-1 (PD-1) antibodies from mice stimulated by APS and to confirm whether the isolated anti-PD-1 antibody could inhibit the interaction of PD-1 with the programmed death-ligand 1 (PD-L1), resulting in tumor growth inhibition. The isolated single-chain fragment variable (scFv) S12 exhibited the highest binding affinity of 20 nM to PD-1, completed the interaction between PD-1 and PD-L1, and blocked the effect of PD-L1-induced T cell exhaustion in peripheral blood mononuclear cells in vitro. In the animal model, the tumor growth inhibition effect after scFv S12 treatment was approximately 48%. However, meaningful synergistic effects were not observed when scFv S12 was used as a cotreatment with ixabepilone. Moreover, this treatment caused a reduction in the number of tumor-associated macrophages in the tumor tissue. These experimental results indirectly indicate the ability of APS to induce specific antibodies associated with the immune checkpoint system and the potential benefits for improving immunity in humans.

Molecular cloning and characterization of Taiwan macaque lactoferrin.

BACKGROUND: Lactoferrin (LF) is an iron-binding glycoprotein that plays an important role in combating a wide range of pathogens and contributes innate protective defenses of mammals. METHODS: We cloned and sequenced the full-length cDNA for LF from Taiwan macaque. The antimicrobial activity and iron-binding ability of the purified recombinant macaque LF (rmLF) were determined and compared with those of human LF (hLF). RESULTS AND CONCLUSIONS: The complete mLF cDNA (GenBank: EU523857) encoded a 710-aa precursor with a 19-aa signal peptide. The nucleotide sequence of mLF showed the highest identity to the rhesus monkey LF (98%), whereas the putative amino acid sequence of mLF showed the highest identity to the hLF (90%). The rmLF and natural hLF showed almost equivalent antibacterial activities against Klebsiella pneumoniae and mLF presented a slightly lower activity against Listeria monocytogenes than natural hLF. In addition, the patterns of iron release from mLF and hLF were nearly identical.

Dual-drug loaded nanoparticles of Epigallocatechin-3-gallate (EGCG)/Ascorbic acid enhance therapeutic efficacy of EGCG in a APPswe/PS1dE9 Alzheimer's disease mice model.

Epigallocatechin-3-gallate (EGCG) is a candidate for treatment of Alzheimer's disease (AD) but its inherent instability limits bioavailability and effectiveness. We found that EGCG displayed increased stability when formulated as dual-drug loaded PEGylated PLGA nanoparticles (EGCG/AA NPs). Oral administration of EGCG/AA NPs in mice resulted in EGCG accumulation in all major organs, including the brain. Pharmacokinetic comparison of plasma and brain accumulation following oral administration of free or EGCG/AA NPs showed that, whilst in both cases initial EGCG concentrations were similar, long-term (5-25 h) concentrations were ca. 5 fold higher with EGCG/AA NPs. No evidence was found that EGCG/AA NPs utilised a specific pathway across the blood-brain barrier (BBB). However, EGCG, empty NPs and EGCG/AA NPs all induced tight junction disruption and opened the BBB in vitro and ex vivo. Oral treatment of APPswe/PS1dE9 (APP/PS1) mice, a familial model of AD, with EGCG/AA NPs resulted in a marked increase in synapses, as judged by synaptophysin (SYP) expression, and reduction of neuroinflammation as well as amyloid ß (Aß) plaque burden and cortical levels of soluble and insoluble Aß(1-42) peptide. These morphological changes were accompanied by significantly enhanced spatial learning and memory. Mechanistically, we propose that stabilisation of EGCG in NPs complexes and a destabilized BBB led to higher therapeutic EGCG concentrations in the brain. Thus EGCG/AA NPs have the potential to be developed as a safe and strategy for the treatment of AD.

Ethnic Disparities in Blood Pressure: A Population-based Study.

Taiwan's indigenous population exhibits a higher mortality of cardiovascular disease, but current research has not reported any associations among ethnicities on the blood pressure (BP). We randomly selected representative samples in this population-based study. We measured height, weight, hip and waist circumferences, and blood pressure in a screening survey. Systolic BP and diastolic BP were significantly higher in the indigenous population. Among women, prevalence rates of DBP > 90 mmHg among indigenes (32.9 %) were significantly high than those in Han Chinese (17.4 %). Based on multivariate analysis adjusted for covariates, the results showed gender and ethnicity to be significantly correlated with systolic and diastolic BP. Gender was a modifier between ethnicity and BP. Furthermore, we found an additive effect between ethnicity and age on systolic and diastolic BP by gender. Our study showed independent additive effects on systolic BP and diastolic BP between ethnicity and age by gender.