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1.
Int J Mol Sci ; 24(18)2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37762596

ABSTRACT

Mitochondria are crucial for cellular energy metabolism and are involved in signaling, aging, and cell death. They undergo dynamic changes through fusion and fission to adapt to different cellular states. In this study, we investigated the effect of knocking out the dynamin 1-like protein (Dnm1l) gene, a key regulator of mitochondrial fission, in neural stem cells (NSCs) differentiated from Dnm1l knockout embryonic stem cells (Dnm1l-/- ESCs). Dnm1l-/- ESC-derived NSCs (Dnm1l-/- NSCs) exhibited similar morphology and NSC marker expression (Sox2, Nestin, and Pax6) to brain-derived NSCs, but lower Nestin and Pax6 expression than both wild-type ESC-derived NSCs (WT-NSCs) and brain-derived NSCs. In addition, compared with WT-NSCs, Dnm1l-/- NSCs exhibited distinct mitochondrial morphology and function, contained more elongated mitochondria, showed reduced mitochondrial respiratory capacity, and showed a metabolic shift toward glycolysis for ATP production. Notably, Dnm1l-/- NSCs exhibited impaired self-renewal ability and accelerated cellular aging during prolonged culture, resulting in decreased proliferation and cell death. Furthermore, Dnm1l-/- NSCs showed elevated levels of inflammation and cell stress markers, suggesting a connection between Dnm1l deficiency and premature aging in NSCs. Therefore, the compromised self-renewal ability and accelerated cellular aging of Dnm1l-/- NSCs may be attributed to mitochondrial fission defects.


Subject(s)
Cellular Senescence , Mitochondria , Nestin , Mitochondria/genetics , Embryonic Stem Cells
2.
Int J Infect Dis ; 134: 8-14, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37172775

ABSTRACT

OBJECTIVES: It is unclear whether the poor outcome of patients with severe vancomycin-resistant enterococci (VRE) infection is attributable to vancomycin resistance or to Enterococcus faecium (Efm), which predominates among VRE. METHODS: Retrospective study of a prospectively identified cohort from nationwide surveillance. A cohort of consecutive, nonduplicate episodes of monomicrobial bloodstream infections (BSIs) caused by Efm in 2016 was selected. The primary outcome was all-cause, 30-day, in-hospital mortality. Inverse probability weighting was applied using the propensity score for vancomycin-resistant Efm (VREfm) BSI. RESULTS: A total of 241 Efm BSI episodes were included, of which 59 (24.5%) were VREfm. Patients with VREfm BSI were younger but had similar comorbidities to those with vancomycin-sensitive Efm (VSEfm) BSI. Multivariable logistic regression revealed that younger age, previous piperacillin-tazobactam use, and steroid use were significant risk factors for VREfm BSI, but 30-day in-hospital mortality did not differ significantly between groups (35.6% and 23.6% for VREfm and VSEfm, respectively; odds ratio, 1.79; 95% confidence interval, 0.95-3.37; P = 0.101). However, Cox regression with inverse probability weighting revealed that vancomycin resistance was independently associated with an increased risk of mortality (adjusted hazard ratio, 2.18; 95% confidence interval, 1.03-4.62; P = 0.041). CONCLUSION: In patients with Efm BSI, vancomycin resistance was independently associated with mortality.


Subject(s)
Bacteremia , Enterococcus faecium , Gram-Positive Bacterial Infections , Sepsis , Vancomycin-Resistant Enterococci , Humans , Vancomycin/pharmacology , Vancomycin/therapeutic use , Vancomycin Resistance , Retrospective Studies , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacteremia/drug therapy , Bacteremia/epidemiology , Gram-Positive Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/epidemiology , Sepsis/drug therapy
4.
Front Psychol ; 13: 971569, 2022.
Article in English | MEDLINE | ID: mdl-36389518

ABSTRACT

As an important factor related to the interests of enterprises, the attitude and behavior of employees are related to the company's survival and the realization of business objectives. However, in recent years, with the rapid development of emerging industries and industry changes, the turnover rate of employees in the whole enterprise has been greatly improved. Frequent turnover of personnel will have a great impact on the stability of the company, the competitiveness of the enterprise, and the operating cost. Employee loyalty and corporate culture satisfaction assessment is the core of sustainable corporate development, but most of the traditional analysis studies are based on the performance approach, using employee overtime, employee achievement, and company effectiveness as data sources, the former performance data is only a side view of the company's situation, the latter as the data source of this study is a one-sided and involute form, and the data is not stable. Therefore, this paper proposes an analysis of employee loyalty and corporate culture satisfaction assessment based on sentiment analysis, using association rules and sentiment lexicons from anonymous employee evaluations to analyze the actual data.

5.
Front Psychol ; 13: 965658, 2022.
Article in English | MEDLINE | ID: mdl-36211860

ABSTRACT

With the progress of social production, the competition for talents among enterprises is fierce, and the market often lacks capable leaders, which leads to the lack of management of enterprise employees and cannot bring more economic benefits to enterprises. Traditional leaders make subordinate employees work actively and achieve the common goal of the enterprise by exerting their own leadership characteristics and observing their subordinates, but they cannot take care of the psychological state of each employee, resulting in the employee's work efficiency is not very high. In recent years, charismatic leadership has become an important economic leader in the new era, and the theoretical spirit of charismatic leadership can well guide employees to work actively. Artificial intelligence affective computing can well identify the psychological state of the subject, and the combination of artificial intelligence affective computing and charismatic leadership can achieve effective management of employees through the predictive analysis of employees' psychological state. This paper compares the psychological state prediction analysis of employees' work attitudes between charismatic leaders based on artificial intelligence affective computing and traditional leaders through experiments. The results show that: charismatic leaders based on artificial intelligence affective computing predictive analytics can improve sensitivity to employee needs, resulting in an 8.2% increase in employee trust in leadership, a 4.4% increase in employee commitment to achieving organizational goals, and a 19.3% increase in employee job satisfaction. The psychological state prediction analysis of charismatic leaders based on artificial intelligence affective computing on employees' work attitudes can improve the work efficiency of employees and the economic benefits of enterprises.

6.
Cells ; 11(20)2022 10 17.
Article in English | MEDLINE | ID: mdl-36291134

ABSTRACT

As a novel cell type from eight-cell-stage embryos, extended pluripotent stem cells (EPSCs) are known for diverse differentiation potency in both extraembryonic and embryonic lineages, suggesting new possibilities as a developmental research model. Although various features of EPSCs have been defined, their ability to directly transfer extended pluripotency to differentiated somatic cells by cell fusion remains to be elucidated. Here, we derived EPSCs from eight-cell mouse embryos and confirmed their extended pluripotency at the molecular level and extraembryonic differentiation ability. Then, they were fused with OG2+/- ROSA+/- neural stem cells (NSCs) by the polyethylene-glycol (PEG)-mediated method and further analyzed. The resulting fused hybrid cells exhibited pluripotential markers with upregulated EPSC-specific gene expression. Furthermore, the hybrid cells contributed to the extraembryonic and embryonic lineages in vivo and in vitro. RNA sequencing analysis confirmed that the hybrid cells showed distinct global expression patterns resembling EPSCs without parental expression of NSC markers, indicating the complete acquisition of extended pluripotency and the erasure of the somatic memory of NSCs. Furthermore, ultrastructural observation and metabolic analysis confirmed that the hybrid cells rearranged the mitochondrial morphology and bivalent metabolic profile to those of EPSCs. In conclusion, the extended pluripotency of EPSCs could be transferred to somatic cells through fusion-induced reprogramming.


Subject(s)
Pluripotent Stem Cells , Mice , Animals , Cell Fusion , Pluripotent Stem Cells/metabolism , Cell Differentiation , Polyethylenes/metabolism , Glycols
7.
Int J Infect Dis ; 122: 506-513, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35752376

ABSTRACT

OBJECTIVES: Vancomycin and teicoplanin are glycopeptides with activity against Enterococcus faecium. However, studies on the clinical efficacy of teicoplanin are limited. This study aimed to compare the therapeutic efficacy of teicoplanin and vancomycin in E. faecium bacteremia. METHODS: We identified patients with bloodstream infections prospectively from July 2015 to December 2016 in 14 hospitals as part of a multicenter nationwide surveillance. Patients with E. faecium monomicrobial bacteremia were selected. Teicoplanin and vancomycin groups included patients treated with either agent for ≥48 hours. The primary outcome was 30-day all-cause in-hospital mortality. The Cox proportional hazards model with inverse probability weighting was used to account for the imbalance in baseline characteristics between the two groups. RESULTS: Among 97 patients with E. faecium bacteremia, 33 (34%) were treated with teicoplanin and 64 (66%) with vancomycin. There were no significant differences in 30-day in-hospital mortality (18.2% vs 26.6%, P = 0.358) and 7-day mortality (6.1% vs 15.6%, P = 0.212). Furthermore, multivariable analysis confirmed that the use of teicoplanin was not significantly associated with mortality (adjusted odds ratio, 0.72; 95% confidence interval, 0.28-1.86; P = 0.494). CONCLUSION: We found no significant differences in the clinical outcomes. These findings suggest teicoplanin as a useful alternative to vancomycin.


Subject(s)
Bacteremia , Enterococcus faecium , Gram-Positive Bacterial Infections , Anti-Bacterial Agents/therapeutic use , Bacteremia/epidemiology , Gram-Positive Bacterial Infections/epidemiology , Humans , Microbial Sensitivity Tests , Teicoplanin/therapeutic use , Vancomycin/therapeutic use
8.
Rev. psicol. deport ; 30(3): 242-251, Dic 27, 2021. ilus, tab, graf
Article in English | IBECS | ID: ibc-213871

ABSTRACT

The purpose of this research is to evaluate the South Korean sport psychology consultant and its effect on job performance of all employees related to the athletes’ firms. This research study is based on primary data analysis which measures the sport psychology consultant effect on job performance. To data collection, the study uses specific questions related to sports psychology and job performance of athletes’ firms. For further analysis for the data, the author uses smart PLS software wherein the summary effect among the factors is calculated using regression analysis. Based on extracted correlation coefficients and normalised regression coefficients, the study examines 85 effect sizes in 100 plus samples selected from studies of sports organisation staff and members. Both, South Korean sport psychology and effectiveness are used as independent variables. The job performance of employees of athletes’ firm is the dependent variable of the study. Results found that South Korean sport psychology shows inverse relation between job performances of athletes’ firms. The effectiveness shows a positive effect on the job performance of employees.(AU)


Subject(s)
Humans , Male , Female , Employee Performance Appraisal , Sports , Service Organizations and Firms , Work Engagement , Psychology, Sports , Sports Medicine , Republic of Korea
9.
Cells ; 10(8)2021 07 26.
Article in English | MEDLINE | ID: mdl-34440657

ABSTRACT

Assisted reproductive technologies (ARTs) have developed considerably in recent years; however, they cannot rectify germ cell aplasia, such as non-obstructive azoospermia (NOA) and oocyte maturation failure syndrome. In vitro gametogenesis is a promising technology to overcome infertility, particularly germ cell aplasia. Early germ cells, such as primordial germ cells, can be relatively easily derived from pluripotent stem cells (PSCs); however, further progression to post-meiotic germ cells usually requires a gonadal niche and signals from gonadal somatic cells. Here, we review the recent advances in in vitro male and female germ cell derivation from PSCs and discuss how this technique is used to understand the biological mechanism of gamete development and gain insight into its application in infertility.


Subject(s)
Gametogenesis , Germ Cells/physiology , Pluripotent Stem Cells/physiology , Animals , Cells, Cultured , Female , Fertility , Humans , Infertility/physiopathology , Infertility/therapy , Male , Oogenesis , Ovum/physiology , Reproductive Techniques, Assisted , Spermatogenesis , Spermatogonia/physiology
10.
Elife ; 102021 07 14.
Article in English | MEDLINE | ID: mdl-34259624

ABSTRACT

Multidrug-resistant Streptococcus pneumoniae emerge through the modification of core genome loci by interspecies homologous recombinations, and acquisition of gene cassettes. Both occurred in the otherwise contrasting histories of the antibiotic-resistant S. pneumoniae lineages PMEN3 and PMEN9. A single PMEN3 clade spread globally, evading vaccine-induced immunity through frequent serotype switching, whereas locally circulating PMEN9 clades independently gained resistance. Both lineages repeatedly integrated Tn916-type and Tn1207.1-type elements, conferring tetracycline and macrolide resistance, respectively, through homologous recombination importing sequences originating in other species. A species-wide dataset found over 100 instances of such interspecific acquisitions of resistance cassettes and flanking homologous arms. Phylodynamic analysis of the most commonly sampled Tn1207.1-type insertion in PMEN9, originating from a commensal and disrupting a competence gene, suggested its expansion across Germany was driven by a high ratio of macrolide-to-ß-lactam consumption. Hence, selection from antibiotic consumption was sufficient for these atypically large recombinations to overcome species boundaries across the pneumococcal chromosome.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial/drug effects , Drug Resistance, Bacterial/genetics , Gene Transfer, Horizontal , DNA Transposable Elements , Genes, Bacterial/genetics , Germany , Humans , Macrolides/pharmacology , Phylogeny , Pneumococcal Vaccines , Serogroup , Serotyping , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/genetics
11.
Microorganisms ; 9(4)2021 Apr 10.
Article in English | MEDLINE | ID: mdl-33920171

ABSTRACT

Since the introduction of the pneumococcal conjugate vaccine, an increase in the incidence of Streptococcus pneumoniae serotype 19A and sequence type 320 (19A-ST320) isolates have been observed worldwide including in South Korea. We conducted a genome-wide analysis to investigate the temporal genetic changes in 26 penicillin-non-susceptible 19A-ST320 pneumococcal isolates from a hospital in South Korea over a period of 17 years (1999; 2004 to 2015). Although the strains were isolated from a single hospital and showed the same genotype and serotype, a whole-genome sequencing (WGS) analysis revealed that the S. pneumoniae isolates showed more extensive genetic variations compared with a reference isolate obtained in 1999. A phylogenetic analysis based on single nucleotide polymorphisms (SNPs) showed that the pneumococcal isolates from South Korea were not grouped together into limited clusters among the 19A-ST320 isolates from several continents. It was predicted that recombination events occurred in 11 isolates; larger numbers of SNPs were found within recombination blocks compared with point mutations identified in five isolates. WGS data indicated that S. pneumoniae 19A-ST320 isolates might have been introduced into South Korea from various other countries. In addition, it was revealed that recombination may play a great role in the evolution of pneumococci even in very limited places and periods.

12.
J Glob Antimicrob Resist ; 24: 387-394, 2021 03.
Article in English | MEDLINE | ID: mdl-33548495

ABSTRACT

OBJECTIVES: Antimicrobial stewardship is a strategy to combat antimicrobial resistance in hospitals. Given the burden and impact of antimicrobial resistance in the Asia Pacific, it is important to document capacity and gaps in antimicrobial stewardship programmes (ASP). We aimed to understand existing capacities and practices, and define the resources needed to establish antimicrobial stewardship where it is lacking. METHODS: An anonymous online survey, consisting of questions on antimicrobial control at country, hospital and programme levels, was circulated to healthcare providers in the field of infectious diseases and microbiology through Asian Network for Surveillance of Resistant Pathogens, ReAct Group and the Australasian Society for infectious Diseases. RESULTS: 139 participants from 16 countries or regions completed the survey. The majority of participants were adult infectious diseases physicians (61/139, 43.9%) and microbiologists (31/139, 22.3%). Participants from 7 countries reported that antimicrobials can be obtained without prescriptions. Despite the high percentage (75.5%) of respondents working in large hospitals, only 22/139 participants (15.8%) from Australia, China, Singapore, Taiwan, Thailand and Vietnam reported having more than 10 infectious diseases physicians. Hospital empiric antimicrobial guidelines for common infections were available according to 110/139 (79.1%) participants. Pre-authorisation of antimicrobials was reported by 88/113 (77.9%) respondents while prospective audit and feedback was reported by 93/114 (81.6%). Automatic stop orders and culture-guided de-escalation were reported by only 52/113 (46.0%) and 27/112 (24.1%) respectively. CONCLUSION: The survey reveals a wide range of ASP development in Asia Pacific. Establishing national workgroups and guidelines will help advance antimicrobial stewardship in this diverse region.


Subject(s)
Antimicrobial Stewardship , Adult , Australia , China , Humans , Singapore , Taiwan , Thailand , Vietnam , Workforce
13.
Clin Infect Dis ; 71(9): e487-e496, 2020 12 03.
Article in English | MEDLINE | ID: mdl-31994704

ABSTRACT

BACKGROUND: Clinically relevant categorization of antimicrobial resistance is critical to mitigating the threat it poses. Difficult-to-treat resistance (DTR) is a recently proposed category defined as nonsusceptibility to all first-line antibiotic agents. METHODS: A retrospective study was conducted with nonduplicate cases of gram-negative bloodstream infection (GNBSI) caused by 4 major taxa (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter species) identified from a nationwide surveillance database. DTR was defined as nonsusceptibility to all the ß-lactams and fluoroquinolones tested. Patient characteristics and mortality were compared between DTR GNBSI and GNBSI caused by carbapenem-resistant but not DTR and extended-spectrum cephalosporin-resistant but not DTR isolates using Centers for Disease Control and Prevention definitions. Adjusted odds ratios (aORs) for 30-day in-hospital mortality were examined for DTR in overall and in propensity score-matched cohorts. RESULTS: A total of 1167 episodes of monomicrobial GNBSI were identified, and 147 (12.6%) of the isolates were DTR. The majority of DTR isolates were Acinetobacter species (79.6%) and P. aeruginosa (17.7%). DTR infections were associated with previous antibiotic use, healthcare contact, ventilator use, and lower respiratory tract infection. Crude mortality for GNBSI caused by DTR was 50.3%. A multivariable model showed that only DTR, but not other categories, was significantly associated with mortality (adjusted odds ratio [aOR], 3.58 [95% confidence interval {CI}, 1.27-10.19]). DTR was also a significant predictor for mortality in the analysis of propensity score-matched cohorts (aOR, 3.48 [95% CI, 1.82-6.79]). CONCLUSIONS: In patients with GNBSI, DTR was associated with higher mortality than those in other resistance categories. Our findings suggest that DTR could be useful for surveillance and prognostication.


Subject(s)
Bacteremia , Gram-Negative Bacterial Infections , Anti-Bacterial Agents/therapeutic use , Bacteremia/drug therapy , Bacteremia/epidemiology , Carbapenems , Drug Resistance, Bacterial , Fluoroquinolones , Gram-Negative Bacteria , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/epidemiology , Humans , Microbial Sensitivity Tests , Retrospective Studies
14.
J Biomed Sci ; 27(1): 8, 2020 Jan 03.
Article in English | MEDLINE | ID: mdl-31900177

ABSTRACT

BACKGROUND: Bacterial isolates with multiple plasmids harbouring different carbapenemase genes have emerged and been identified repeatedly, despite a general notion that plasmids confer fitness cost in bacterial host. In this study, we investigated the effects of plasmids with carbapenemase genes on the fitness and virulence of bacteria. METHODS: Different plasmids harbouring the carbapenemase genes, blaNDM-1 and blaOXA-232, were isolated from a carbapenem-resistant K. pneumoniae strain. Each plasmid was conjugated into the Escherichia coli strain DH5α, and a transconjugant with both plasmids was also obtained by transformation. Their in vitro competitive ability, biofilm formation, serum resistance, survival ability within macrophage and fruit fly, and fly killing ability were evaluated. RESULTS: The transconjugants with a single plasmid showed identical phenotypes to the plasmid-free strain, except that they decreased fly survival after infection. However, significantly increased fitness, virulence and biofilm production were observed consistently for the transconjugant with both plasmids, harbouring blaNDM-1 and blaOXA-232. CONCLUSIONS: Our data indicate that bacteria carrying multiple plasmids encoding different carbapenemases may have increased fitness and virulence, emphasizing the need for diverse strategies to combat antimicrobial resistance.


Subject(s)
Bacterial Infections/genetics , Bacterial Proteins/genetics , Plasmids/genetics , beta-Lactamases/genetics , Bacterial Infections/microbiology , Biofilms/growth & development , Escherichia coli/genetics , Escherichia coli/pathogenicity , Genetic Fitness/genetics , Humans , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/pathogenicity , Transformation, Bacterial/genetics , Virulence/genetics
15.
Korean J Intern Med ; 35(1): 215-221, 2020 01.
Article in English | MEDLINE | ID: mdl-29502362

ABSTRACT

BACKGROUND/AIMS: Healthcare-associated (HCA) infection is a recently suggested new category of community-onset infections. The implications of HCA infections in terms of diagnosis, treatment, and outcomes of spontaneous bacterial peritonitis (SBP) are not well understood. We sought to delineate the differences between community-acquired (CA) SBP and HCA SBP with specific interest in the antimicrobial resistance of causative microorganisms and outcomes. METHODS: We conducted a retrospective cohort study of all SBP episodes with positive ascitic culture and/or blood culture from June 2000 to August 2011. Community-onset SBP episodes were included when they occurred within 48 hours after admission and were classified as CA SBP and HCA SBP based on the predefined criteria. RESULTS: A total of 188 episodes of community-onset SBP were analyzed (65.4% HCA SBP and 34.6% CA SBP). HCA SBP had a higher resistance rate to third-generation cephalosporin (6.8% vs. 1.6%, p = 0.168). The overall 30-day mortality was similar between both groups (37.4% vs. 41.5%, p = 0.638). The independent risk factors for 30-day all-cause mortality in community-onset SBP included high Child-Pugh score, acute kidney injury, and resistance to third-generation cephalosporins; HCA infection was not associated. CONCLUSION: Hepatic functional status, renal dysfunction, and third-generation cephalosporin resistant pathogens more adversely affected the outcome of cirrhotic patients with community-onset SBP rather than HCA infection. The higher rate of third-generation cephalosporin resistance was notable in HCA SBP, which will require a novel approach to empirical antibiotic treatment selection in this population.


Subject(s)
Bacterial Infections , Community-Acquired Infections , Peritonitis , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/diagnosis , Bacterial Infections/drug therapy , Bacterial Infections/epidemiology , Community-Acquired Infections/diagnosis , Community-Acquired Infections/drug therapy , Delivery of Health Care , Drug Resistance, Bacterial , Humans , Liver Cirrhosis/complications , Liver Cirrhosis/diagnosis , Liver Cirrhosis/drug therapy , Peritonitis/diagnosis , Peritonitis/drug therapy , Peritonitis/epidemiology , Retrospective Studies
16.
Vaccine ; 38(38): 6065-6073, 2020 08 27.
Article in English | MEDLINE | ID: mdl-31590932

ABSTRACT

This study was performed to investigate the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae in Asian countries. A prospective surveillance study on S. pneumoniae collected from adult patients (≥50 years old) with invasive pneumococcal disease or community-acquired pneumonia was performed at 66 hospitals in Asian countries (Korea, China, Malaysia, Singapore, the Philippines, and Thailand) in 2012-2017. Serotyping and antimicrobial susceptibility tests of 850 pneumococcal isolates were performed. The proportions of isolates with serotypes covered by 13-valent pneumococcal conjugate vaccine (PCV13) were 37.0% in Korea, 53.4% in China, 77.2% in Malaysia, 35.9% in the Philippines, 68.7% in Singapore, and 60.2% in Thailand. Major serotypes were 19F (10.4%), 19A (10.1%), and 3 (8.5%) in 2012-2017, with different serotype distributions in each country. Macrolide resistance in pneumococci was high (66.8%) and prevalence of multidrug resistance (MDR) also remained high (50.8%). MDR non-PCV13 serotypes such as 11A, 15A, 35B, and 23A have emerged in Asian countries. This study showed the persistent prevalence of 19F and 19A with a noteworthy increase of certain non-PCV13 serotypes in Asian countries. High prevalence of macrolide resistance and MDR was also found in pneumococcal isolates. These data emphasize the need for continued surveillance of pneumococcal epidemiology in Asia in the post-pneumococcal vaccine era.


Subject(s)
Pharmaceutical Preparations , Pneumococcal Infections , Adult , Anti-Bacterial Agents/pharmacology , China/epidemiology , Drug Resistance, Bacterial , Humans , Infant , Macrolides , Malaysia , Microbial Sensitivity Tests , Middle Aged , Philippines , Pneumococcal Infections/epidemiology , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines , Prospective Studies , Republic of Korea , Serogroup , Serotyping , Singapore , Streptococcus pneumoniae , Thailand
17.
Plasmid ; 104: 102417, 2019 07.
Article in English | MEDLINE | ID: mdl-31150689

ABSTRACT

Recently, Escherichia coli isolates co-producing New Delhi metallo-ß-lactamase (NDM)-5 and oxacillinase (OXA)-181 were identified in a tertiary-care hospital of South Korea. Isolate CC1702-1 was collected from urine in January 2017 and isolate CC1706-1 was recovered from a transtracheal aspirate of a hospitalized patient in May 2017. Carbapenemase genes were identified by multiplex PCR and sequencing, and whole genome sequencing was performed subsequently using the PacBio RSII system. Both E. coli isolates belonged to the same clone (ST410) and were resistant to all ß-lactams including carbapenems. We obtained whole plasmid sequences of the isolates: pCC1702-NDM-5 from CC1702-1 and pCC1706-NDM-5 and pCC1706-OXA-181 from CC1706-1. The two E. coli isolates belonged to the same clone (ST410) and they were completely resistant to all ß-lactams, as well as carbapenems. Two blaNDM-5-harboring plasmids belonged to the same incompatibility group, IncFIA/B, and consisted of 79,613 bp and 111,890 bp with 87 and 130 coding sequences, respectively. The genetic structures of the two blaNDM-5-bearing plasmids, which were distinct from the blaNDM-5-bearing plasmids from the Klebsiella pneumoniae isolates previously transmitted from the United Arab Emirates (UAE) to South Korea, differed from each other. While pCC1702-NDM-5 showed high degree of identity with the plasmid from a multidrug-resistant isolate of Citrobacter fruendii P5571 found in China, pCC1706-NDM-5 was very similar to the plasmid from a multidrug-resistant isolate of E. coli AMA1176 found in Denmark. pCC1706-OXA-181, which was a 51 kb, self-transmissible IncX3 plasmid, was identical to the E. coli plasmids pAMA1167-OXA-181 from Denmark and pOXA-181-WCHEC14828 from China. Plasmids harboring blaNDM-5 in E. coli isolates might not be transferred from K. pneumoniae isolates co-producing NDM-5 and OXA-181. They probably originated from multiple sources.


Subject(s)
Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Escherichia coli Proteins/genetics , Escherichia coli/genetics , Plasmids/genetics , beta-Lactamases/genetics , Anti-Bacterial Agents/pharmacology , Conjugation, Genetic , Escherichia coli/drug effects , Escherichia coli/isolation & purification , Escherichia coli Infections/drug therapy , Escherichia coli Proteins/biosynthesis , Genotype , Humans , Microbial Sensitivity Tests , Republic of Korea/epidemiology , beta-Lactamases/biosynthesis
18.
Microbiol Immunol ; 63(6): 206-212, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31081554

ABSTRACT

In this study, the whole genome sequences of two Streptococcus pneumoniae clinical isolates from South Korea were determined and compared. They were found to be the same serotype (11 A) and multilocus sequence typing analysis showed that they are single-locus variants (SLVs; ST8279 and ST166) of each other, differing at one allele (aroE). However, the ST8279 strain is extensively drug-resistant (XDR) whereas the ST166 strain is not. The genome of the XDR strain is very similar in structure to that of two previously reported genomes, AP200 (11 A:ST62) and 70585 (5:ST5803); however, some regions were inverted and there were some exogenous regions in the ST8279 strain. It was found that 6,502 single nucleotide polymorphisms are dispersed across the genome between the two serotype 11 A ST8279 and ST166 strains. Many of them are located in genes associated with antibiotic resistance. In addition, many amino acid differences were also identified in genes involved in DNA repair (mutL, uvrA and uvrC) and recombination (recU, recR and recA). On the basis of these results, it was inferred that the XDR strain did not evolve from its SLV via a single recombination event involving a large portion of the genome including the aroE gene. Rather, the strain likely evolved through many point mutations and recombination events involving small portions of the genome.


Subject(s)
Drug Resistance, Multiple, Bacterial/genetics , Pneumococcal Infections/microbiology , Serogroup , Streptococcus pneumoniae/genetics , DNA, Bacterial/genetics , Genes, Bacterial/genetics , Genome, Bacterial , Genotyping Techniques , Humans , Microbial Sensitivity Tests , Multilocus Sequence Typing , Polymorphism, Single Nucleotide , Republic of Korea , Sequence Alignment , Serotyping , Streptococcus pneumoniae/classification , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/isolation & purification , Whole Genome Sequencing
19.
Int J Med Microbiol ; 309(3-4): 194-198, 2019.
Article in English | MEDLINE | ID: mdl-30885571

ABSTRACT

We obtained nine Klebsiella pneumoniae isolates successively isolated from a single patient. Four pairs (M1-M4 and NM1-NM4) obtained simultaneously from the same site showed different colony types, mucoid and non-mucoid, while the final isolate (M5) was isolated alone from the blood and showed a mucoid phenotype. The whole genome of isolate M5 was sequenced de novo using the PacBio RSII system, while the others were sequenced with an Illumina Hiseq4000 and mapped to the genome sequences of M5. To identify insertions or deletions in the cps locus, we amplified and sequenced cps locus genes. We identified insertion sequence (IS) elements in several genes of the cps locus or one amino acid substitution in WcaJ in all non-mucoid isolates. Five additional amino acid alterations in RpsJ, LolE, Lon-2, PpsE, and a hypothetical protein were detected in some mucoid and non-mucoid isolates. Based on the genome data and cps locus sequences, the mucoid phenotype may have been lost or converted into the non-mucoid phenotype because of the insertion of IS elements or amino acid alterations at this locus. We inferred a within-host evolutionary scenario, in which non-mucoid variants emerged repeatedly from mucoid isolates, but may be short-lived because of their low fitness.


Subject(s)
Bacterial Capsules/metabolism , Klebsiella Infections/microbiology , Klebsiella pneumoniae/metabolism , Bacterial Capsules/genetics , Bacterial Proteins/genetics , Biological Evolution , DNA, Bacterial/genetics , Genome, Bacterial/genetics , Humans , Klebsiella pneumoniae/genetics , Male , Middle Aged , Mutation , Phenotype , Polysaccharides, Bacterial/genetics
20.
J Korean Med Sci ; 34(2): e17, 2019 Jan 14.
Article in English | MEDLINE | ID: mdl-30636947

ABSTRACT

We implemented a carbapenem-saving strategy in hemato-oncology patients from 2013, using an empirical combination of piperacillin-tazobactam and amikacin for high-risk hemato-oncology patients with febrile neutropenia, who remain hemodynamically unstable > 72 hours despite initial cefepime treatment. All-cause mortality was not different between the two periods (6.54 and 6.57 deaths per 1,000 person-day, P = 0.926). Group 2 carbapenem use significantly decreased after strategy implementation (78.43 vs. 67.43 monthly days of therapy, P = 0.018), while carbapenem-resistant gram-negative bacilli did not show meaningful changes during the study period. Our carbapenem-saving strategy could effectively suppress carbapenem use without an increase of overall mortality.


Subject(s)
Amikacin/therapeutic use , Carbapenems/therapeutic use , Febrile Neutropenia/drug therapy , Piperacillin, Tazobactam Drug Combination/therapeutic use , Amikacin/pharmacology , Anti-Bacterial Agents/therapeutic use , Carbapenems/pharmacology , Drug Resistance, Bacterial , Enterobacteriaceae/drug effects , Febrile Neutropenia/microbiology , Febrile Neutropenia/pathology , Humans , Piperacillin, Tazobactam Drug Combination/pharmacology
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