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1.
Cell ; 182(3): 641-654.e20, 2020 08 06.
Article in English | MEDLINE | ID: mdl-32615085

ABSTRACT

Targeting glycolysis has been considered therapeutically intractable owing to its essential housekeeping role. However, the context-dependent requirement for individual glycolytic steps has not been fully explored. We show that CRISPR-mediated targeting of glycolysis in T cells in mice results in global loss of Th17 cells, whereas deficiency of the glycolytic enzyme glucose phosphate isomerase (Gpi1) selectively eliminates inflammatory encephalitogenic and colitogenic Th17 cells, without substantially affecting homeostatic microbiota-specific Th17 cells. In homeostatic Th17 cells, partial blockade of glycolysis upon Gpi1 inactivation was compensated by pentose phosphate pathway flux and increased mitochondrial respiration. In contrast, inflammatory Th17 cells experience a hypoxic microenvironment known to limit mitochondrial respiration, which is incompatible with loss of Gpi1. Our study suggests that inhibiting glycolysis by targeting Gpi1 could be an effective therapeutic strategy with minimum toxicity for Th17-mediated autoimmune diseases, and, more generally, that metabolic redundancies can be exploited for selective targeting of disease processes.


Subject(s)
Cell Differentiation/immunology , Encephalomyelitis, Autoimmune, Experimental/immunology , Glucose-6-Phosphate Isomerase/metabolism , Glycolysis/genetics , Oxidative Phosphorylation , Pentose Phosphate Pathway/physiology , Th17 Cells/metabolism , Animals , Cell Hypoxia/genetics , Cell Hypoxia/immunology , Chimera/genetics , Chromatography, Gas , Chromatography, Liquid , Clostridium Infections/immunology , Cytokines/deficiency , Cytokines/genetics , Cytokines/metabolism , Encephalomyelitis, Autoimmune, Experimental/genetics , Encephalomyelitis, Autoimmune, Experimental/metabolism , Glucose-6-Phosphate Isomerase/genetics , Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)/genetics , Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)/metabolism , Glycolysis/immunology , Homeostasis/genetics , Homeostasis/immunology , Inflammation/genetics , Inflammation/immunology , Mass Spectrometry , Mice , Mice, Inbred C57BL , Mitochondria/metabolism , Mucous Membrane/immunology , Mucous Membrane/metabolism , Mucous Membrane/microbiology , Pentose Phosphate Pathway/genetics , Pentose Phosphate Pathway/immunology , RNA-Seq , Single-Cell Analysis , Th17 Cells/immunology , Th17 Cells/pathology
2.
Mol Cell ; 69(4): 610-621.e5, 2018 02 15.
Article in English | MEDLINE | ID: mdl-29452640

ABSTRACT

Upon glucose restriction, eukaryotic cells upregulate oxidative metabolism to maintain homeostasis. Using genetic screens, we find that the mitochondrial serine hydroxymethyltransferase (SHMT2) is required for robust mitochondrial oxygen consumption and low glucose proliferation. SHMT2 catalyzes the first step in mitochondrial one-carbon metabolism, which, particularly in proliferating cells, produces tetrahydrofolate (THF)-conjugated one-carbon units used in cytoplasmic reactions despite the presence of a parallel cytoplasmic pathway. Impairing cytoplasmic one-carbon metabolism or blocking efflux of one-carbon units from mitochondria does not phenocopy SHMT2 loss, indicating that a mitochondrial THF cofactor is responsible for the observed phenotype. The enzyme MTFMT utilizes one such cofactor, 10-formyl THF, producing formylmethionyl-tRNAs, specialized initiator tRNAs necessary for proper translation of mitochondrially encoded proteins. Accordingly, SHMT2 null cells specifically fail to maintain formylmethionyl-tRNA pools and mitochondrially encoded proteins, phenotypes similar to those observed in MTFMT-deficient patients. These findings provide a rationale for maintaining a compartmentalized one-carbon pathway in mitochondria.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/pathology , Glycine Hydroxymethyltransferase/metabolism , Mitochondria/genetics , Peptide Chain Initiation, Translational , RNA, Transfer, Met/chemistry , Serine/chemistry , Animals , Apoptosis , Breast Neoplasms/metabolism , CRISPR-Cas Systems , Cell Proliferation , Cytosol/metabolism , Female , Glycine Hydroxymethyltransferase/antagonists & inhibitors , Glycine Hydroxymethyltransferase/genetics , Humans , Mice , Mice, Inbred NOD , Mice, SCID , Mitochondria/drug effects , Mitochondria/metabolism , Protein Processing, Post-Translational , RNA, Transfer, Met/genetics , RNA, Transfer, Met/metabolism , Serine/genetics , Serine/metabolism , Tetrahydrofolates/pharmacology , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
3.
Small ; 20(23): e2309162, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38152973

ABSTRACT

Polymeric solid electrolytes have attracted tremendous interest in high-safety and high-energy capacity lithium-sulfur (Li─S) batteries. There is, however, still a dilemma to concurrently attain high Li-ion conductivity and high mechanical strength that effectively suppress the Li-dendrite growth. Accordingly, a rapidly Li-ion conducting solid electrolyte is prepared by grafting pyrrolidinium cation (PYR+)-functionalized poly(ethylene glycol) onto the poly(arylene ether sulfone) backbone (PAES-g-2PEGPYR). The PYR+ groups effectively immobilize anions of Li-salts in Li-conductive PEGPYR domains phase-separated from PAES matrix to enhance the single-ion conduction. The tailored PAES-g-2PEGPYR membrane shows a high Li-ion transference number of 0.601 and superior ionic conductivity of 1.38 mS cm-1 in the flexible solid state with the tensile strength of 1.0 MPa and Young's modulus of 1.5 MPa. Moreover, this PAES-g-2PEGPYR membrane exhibits a high oxidation potential (5.5 V) and high thermal stability up to 200 (C. The Li/PAES-g-2PEGPYR/Li cell stably operates for 1000 h without any short circuit, and the rechargeable Li/PAES-g-2PEGPYR/S cell discharges a capacity of 1004.7 mAh g-1 at C/5 with the excellent rate capability and the prominent cycling performance of 95.3% retention after 200 cycles.

4.
Med Mycol ; 62(6)2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935912

ABSTRACT

Candida parapsilosis is globally distributed and recognised for causing an increasing proportion of invasive Candida infections. It is associated with high crude mortality in all age groups. It has been particularly associated with nosocomial outbreaks, particularly in association with the use of invasive medical devices such as central venous catheters. Candida parapsilosis is one of the pathogens considered in the WHO priority pathogens list, and this review was conducted to inform the ranking of the pathogen in the list. In this systematic review, we searched PubMed and Web of Science to find studies between 2011 and 2021 reporting on the following criteria for C. parapsilosis infections: mortality, morbidity (hospitalisation and disability), drug resistance, preventability, yearly incidence, and distribution/emergence. We identified 336 potentially relevant papers, of which 51 were included in the analyses. The included studies confirmed high mortality rates, ranging from 17.5% to 46.8%. Data on disability and sequelae were sparse. Many reports highlighted concerns with azole resistance, with resistance rates of >10% described in some regions. Annual incidence rates were relatively poorly described, although there was clear evidence that the proportion of candidaemia cases caused by C. parapsilosis increased over time. While this review summarises current data on C.parapsilosis, there remains an urgent need for ongoing research and surveillance to fully understand and manage this increasingly important pathogen.


Subject(s)
Antifungal Agents , Candida parapsilosis , Drug Resistance, Fungal , World Health Organization , Humans , Candida parapsilosis/drug effects , Antifungal Agents/therapeutic use , Antifungal Agents/pharmacology , Incidence , Candidiasis/epidemiology , Candidiasis/microbiology , Cross Infection/epidemiology , Cross Infection/microbiology
5.
Med Mycol ; 62(6)2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935900

ABSTRACT

The World Health Organization (WHO) in 2022 developed a fungal priority pathogen list. Candida auris was ultimately ranked as a critical priority pathogen. PubMed and Web of Science were used to find studies published from 1 January 2011 to 18 February 2021, reporting on predefined criteria including: mortality, morbidity (i.e., hospitalization and disability), drug resistance, preventability, yearly incidence, and distribution/emergence. Thirty-seven studies were included in the final analysis. The overall and 30-day mortality rates associated with C. auris candidaemia ranged from 29% to 62% and 23% to 67%, respectively. The median length of hospital stay was 46-68 days, ranging up to 140 days. Late-onset complications of C. auris candidaemia included metastatic septic complications. Resistance rates to fluconazole were as high as 87%-100%. Susceptibility to isavuconazole, itraconazole, and posaconazole varied with MIC90 values of 0.06-1.0 mg/l. Resistance rates to voriconazole ranged widely from 28% to 98%. Resistance rates ranged between 8% and 35% for amphotericin B and 0%-8% for echinocandins. Over the last ten years, outbreaks due to C. auris have been reported in in all WHO regions. Given the outbreak potential of C. auris, the emergence and spread of MDR strains, and the challenges associated with its identification, and eradication of its environmental sources in healthcare settings, prevention and control measures based on the identified risk factors should be evaluated for their effectiveness and feasibility. Global surveillance studies could better inform the incidence rates and distribution patterns to evaluate the global burden of C. auris infections.


Subject(s)
Antifungal Agents , Candida auris , Candidiasis , Drug Resistance, Fungal , World Health Organization , Humans , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Candidiasis/microbiology , Candidiasis/epidemiology , Candidiasis/drug therapy , Candida auris/drug effects , Microbial Sensitivity Tests , Candidemia/epidemiology , Candidemia/microbiology , Candidemia/drug therapy , Disease Outbreaks , Candida/drug effects , Candida/classification , Candida/isolation & purification , Incidence
6.
Med Mycol ; 62(6)2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935903

ABSTRACT

Histoplasmosis, a significant mycosis primarily prevalent in Africa, North and South America, with emerging reports globally, poses notable health challenges, particularly in immunocompromised individuals such as people living with HIV/AIDS and organ transplant recipients. This systematic review, aimed at informing the World Health Organization's Fungal Priority Pathogens List, critically examines literature from 2011 to 2021 using PubMed and Web of Science, focusing on the incidence, mortality, morbidity, antifungal resistance, preventability, and distribution of Histoplasma. We also found a high prevalence (22%-44%) in people living with HIV, with mortality rates ranging from 21% to 53%. Despite limited data, the prevalence of histoplasmosis seems stable, with lower estimates in Europe. Complications such as central nervous system disease, pulmonary issues, and lymphoedema due to granuloma or sclerosis are noted, though their burden remains uncertain. Antifungal susceptibility varies, particularly against fluconazole (MIC: ≥32 mg/l) and caspofungin (MICs: 4-32 mg/l), while resistance to amphotericin B (MIC: 0.125-0.16 mg/l), itraconazole (MICs: 0.004-0.125 mg/l), and voriconazole (MICs: 0.004-0.125 mg/l) remains low. This review identifies critical knowledge gaps, underlining the need for robust, globally representative surveillance systems to better understand and combat this fungal threat.


Subject(s)
Antifungal Agents , Drug Resistance, Fungal , Histoplasma , Histoplasmosis , World Health Organization , Humans , Histoplasmosis/epidemiology , Histoplasmosis/microbiology , Histoplasmosis/drug therapy , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Histoplasma/drug effects , Histoplasma/isolation & purification , Prevalence , Immunocompromised Host
7.
Med Mycol ; 62(6)2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935910

ABSTRACT

This systematic review evaluates the current global impact of invasive infections caused by Pneumocystis jirovecii (principally pneumonia: PJP), and was carried out to inform the World Health Organization Fungal Priority Pathogens List. PubMed and Web of Science were used to find studies reporting mortality, inpatient care, complications/sequelae, antifungal susceptibility/resistance, preventability, annual incidence, global distribution, and emergence in the past 10 years, published from January 2011 to February 2021. Reported mortality is highly variable, depending on the patient population: In studies of persons with HIV, mortality was reported at 5%-30%, while in studies of persons without HIV, mortality ranged from 4% to 76%. Risk factors for disease principally include immunosuppression from HIV, but other types of immunosuppression are increasingly recognised, including solid organ and haematopoietic stem cell transplantation, autoimmune and inflammatory disease, and chemotherapy for cancer. Although prophylaxis is available and generally effective, burdensome side effects may lead to discontinuation. After a period of decline associated with improvement in access to HIV treatment, new risk groups of immunosuppressed patients with PJP are increasingly identified, including solid organ transplant patients.


Subject(s)
Immunocompromised Host , Invasive Fungal Infections , Pneumocystis carinii , World Health Organization , Humans , Invasive Fungal Infections/epidemiology , Invasive Fungal Infections/prevention & control , Invasive Fungal Infections/mortality , Invasive Fungal Infections/microbiology , Risk Factors , Global Health , Pneumonia, Pneumocystis/microbiology , Pneumonia, Pneumocystis/epidemiology , Pneumonia, Pneumocystis/mortality , Antifungal Agents/therapeutic use , Incidence
8.
Ann Clin Microbiol Antimicrob ; 23(1): 62, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38978096

ABSTRACT

BACKGROUND: This study analyzed the genetic traits and fitness costs of vancomycin-resistant Enterococcus faecium (VREfm) blood isolates carrying Tn1546-type transposons harboring the vanA operon. METHODS: All E. faecium blood isolates were collected from eight general hospitals in South Korea during one-year study period. Antimicrobial susceptibility testing and vanA and vanB PCR were performed. Growth rates of E. faecium isolates were determined. The vanA-positive isolates were subjected to whole genome sequencing and conjugation experiments. RESULTS: Among 308 E. faecium isolates, 132 (42.9%) were positive for vanA. All Tn1546-type transposons harboring the vanA operon located on the plasmids, but on the chromosome in seven isolates. The plasmids harboring the vanA operon were grouped into four types; two types of circular, nonconjugative plasmids (Type A, n = 50; Type B, n = 46), and two types of putative linear, conjugative plasmids (Type C, n = 16; Type D, n = 5). Growth rates of vanA-positive E. faecium isolates were significantly lower than those of vanA-negative isolates (P < 0.001), and reduction in growth rate under vancomycin pressure was significantly larger in isolates harboring putative linear plasmids than in those harboring circular plasmids (P = 0.020). CONCLUSIONS: The possession of vanA operon was costly to bacterial hosts in antimicrobial-free environment, which provide evidence for the importance of reducing vancomycin pressure for prevention of VREfm dissemination. Fitness burden to bacterial hosts was varied by type and size of the vanA operon-harboring plasmid.


Subject(s)
Anti-Bacterial Agents , Bacterial Proteins , Carbon-Oxygen Ligases , DNA Transposable Elements , Enterococcus faecium , Microbial Sensitivity Tests , Operon , Plasmids , Plasmids/genetics , Enterococcus faecium/genetics , Humans , Bacterial Proteins/genetics , Republic of Korea , Carbon-Oxygen Ligases/genetics , Anti-Bacterial Agents/pharmacology , Whole Genome Sequencing , Gram-Positive Bacterial Infections/microbiology , Vancomycin-Resistant Enterococci/genetics , Vancomycin Resistance/genetics , Genetic Fitness , Vancomycin/pharmacology , Conjugation, Genetic
9.
Gerontology ; 70(3): 269-278, 2024.
Article in English | MEDLINE | ID: mdl-38219723

ABSTRACT

INTRODUCTION: In aging populations, the coexistence of multiple health comorbidities represents a significant challenge for clinicians and researchers. Leveraging advances in omics techniques to characterize these health conditions may provide insight into disease pathogenesis as well as reveal biomarkers for monitoring, prognostication, and diagnosis. Researchers have previously established the utility of big data approaches with respect to comprehensive health outcome measurements in younger populations, identifying protein markers that may provide significant health information with a single blood sample. METHODS: Here, we employed a similar approach in two cohorts of older adults, the Baltimore Longitudinal Study of Aging (mean age = 76.12 years) and InCHIANTI Study (mean age = 66.05 years), examining the relationship between levels of serum proteins and 5 key health outcomes: kidney function, fasting glucose, physical activity, lean body mass, and percent body fat. RESULTS: Correlations between proteins and health outcomes were primarily shared across both older adult cohorts. We further identified that most proteins associated with health outcomes in the older adult cohorts were not associated with the same outcomes in a prior study of a younger population. A subset of proteins, adiponectin, MIC-1, and NCAM-120, were associated with at least three health outcomes in both older adult cohorts but not in the previously published younger cohort, suggesting that they may represent plausible markers of general health in older adult populations. CONCLUSION: Taken together, these findings suggest that comprehensive protein health markers have utility in aging populations and are distinct from those identified in younger adults, indicating unique mechanisms of disease with aging.


Subject(s)
Aging , Proteomics , Humans , Aged , Longitudinal Studies , Body Composition , Outcome Assessment, Health Care
10.
Foodborne Pathog Dis ; 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39269884

ABSTRACT

Salmonella is a major cause of foodborne disease and frequently causes human salmonellosis in South Korea. In this study, we investigated the genome diversity, antimicrobial resistance, and virulence of clinical isolates of Salmonella enterica from South Korea. We collected 42 S. enterica subsp. enterica isolates from two hospitals in South Korea. Whole genome sequences were determined. Serovars and sequence types (STs) based on multilocus sequence typing (MLST) were identified from whole genome sequences. Phylogenetic trees based on whole genome sequences and a minimum spanning tree based on MLST were constructed. Human serum resistance assays and gentamicin protection assays were performed to assess in vitro virulence. Nineteen serovars were identified among 42 clinical isolates, including nine Salmonella Typhi isolates. There were inconsistencies between serogroups and phylogenetic clusters in the phylogenetic tree and minimum spanning tree, but high clonality of S. Typhi was observed. Salmonella Typhi isolates were divided into two clusters, corresponding to ST1 and ST2. Isolates of serovars Typhimurium and I4,[5],12:i:- clustered into a group, and a hybrid isolate between the two serovars was identified. Four ciprofloxacin-resistant isolates were identified among nine S. Typhi isolates, and all isolates of S. Enteritidis and S. Panama were resistant to colistin. The gentamicin protection assay revealed that serogroup D1 was significantly less virulent than the other serogroups. Our study suggests high diversity of S. enterica clinical isolates from South Korea and non-monophyly of serogroups. In addition, subgroups of S. Typhi isolates and a hybrid isolate between serovars Typhimurium and I4,[5],12:i:- were identified.

11.
Sensors (Basel) ; 24(12)2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38931762

ABSTRACT

A multichannel speech enhancement system usually consists of spatial filters such as adaptive beamformers followed by postfilters, which suppress remaining noise. Accurate estimation of the power spectral density (PSD) of the residual noise is crucial for successful noise reduction in the postfilters. In this paper, we propose a postfilter utilizing proposed a posteriori speech presence probability (SPP) and noise PSD estimators, which are based on both the coherence and the statistical models. We model the coherence-based a posteriori SPP as a simple function of the magnitude of coherence between two microphone signals and combine it with a single-channel SPP based on statistical models. The coherence-based estimator for the PSD of the noise remaining in the beamformer output in the presence of speech is derived using the pseudo-coherence considering the effect of the beamformers, which is used to construct the coherence-based noise PSD estimator. Then, the final noise PSD estimator is obtained by combining the coherence-based and statistical model-based noise PSD estimators with the proposed SPP. The spectral gain function is also modified, incorporating the proposed SPP. Experimental results demonstrate that the proposed method led to more accurate noise PSD estimation and perceptual evaluation of speech quality scores in various diffuse noise environments, and did not degrade the speech quality under the presence of directional interference, although the proposed method utilizes the coherence information.

12.
Sensors (Basel) ; 24(13)2024 Jun 25.
Article in English | MEDLINE | ID: mdl-39000889

ABSTRACT

Emotions in speech are expressed in various ways, and the speech emotion recognition (SER) model may perform poorly on unseen corpora that contain different emotional factors from those expressed in training databases. To construct an SER model robust to unseen corpora, regularization approaches or metric losses have been studied. In this paper, we propose an SER method that incorporates relative difficulty and labeling reliability of each training sample. Inspired by the Proxy-Anchor loss, we propose a novel loss function which gives higher gradients to the samples for which the emotion labels are more difficult to estimate among those in the given minibatch. Since the annotators may label the emotion based on the emotional expression which resides in the conversational context or other modality but is not apparent in the given speech utterance, some of the emotional labels may not be reliable and these unreliable labels may affect the proposed loss function more severely. In this regard, we propose to apply label smoothing for the samples misclassified by a pre-trained SER model. Experimental results showed that the performance of the SER on unseen corpora was improved by adopting the proposed loss function with label smoothing on the misclassified data.


Subject(s)
Emotions , Speech , Humans , Emotions/physiology , Speech/physiology , Algorithms , Reproducibility of Results , Pattern Recognition, Automated/methods , Databases, Factual
13.
Protein Expr Purif ; 202: 106196, 2023 02.
Article in English | MEDLINE | ID: mdl-36280166

ABSTRACT

Antibodies that block the interaction between PD-1 expressing T-cells and cancer cells expressing PD-L1 play a central role in contemporary immunotherapy regimes [1-3]. We previously reported the isolation of a single chain variable fragment (scFv) of the monoclonal anti-PD-1 antibody Nivolumab, that binds to purified PD-1 and blocked its interaction with PD-L1 [4]. This anti-PD-1 scFv did not, however, function in a cell-based assay designed to detect the disruption of the PD-1/PD-L1 interaction, a result likely due to its poor solubility in tissue culture media. Herein we report that following a series of structure-based rational design analyses, including Aggreescan3D, we have isolated a variant of the anti-PD-1 scFv having significantly improved solubility in tissue culture medium. Moreover, this soluble anti-PD-1 scFv variant disrupted the interaction between PD-1 expressed on Jurkat Cells and PD-L1 expressed on CHO cells. These findings are discussed in terms of the related observation that the residues mutated to form the anti-PD-1 variant are conserved in many other scFvs; thus, the properties of a range of scFvs will likely be enhanced by similar mutations of the conserved residues.


Subject(s)
B7-H1 Antigen , Single-Chain Antibodies , Cricetinae , Animals , Humans , B7-H1 Antigen/genetics , Single-Chain Antibodies/genetics , Single-Chain Antibodies/pharmacology , Single-Chain Antibodies/chemistry , Nivolumab/pharmacology , CHO Cells , Cricetulus , Antibodies, Monoclonal/genetics
14.
Curr Microbiol ; 80(2): 82, 2023 Jan 21.
Article in English | MEDLINE | ID: mdl-36680615

ABSTRACT

Recently, non-diphtheriae Corynebacterium spp. have been increasingly reported in patients. In addition, several novel species of Corynebacterium isolated from humans. Here, we report two cases of human infections caused by Corynebacterium haemomassiliense-like organisms, which had not been identified at the species level by MALDI-TOF MS analysis. They were revealed to be closely related to C. haemomassiliense, a recently described species by three housekeeping genes (16S rRNA, rpoB, and gyrA) and phenotypic features. Both strains were multidrug-resistant but susceptible to vancomycin, meropenem, and linezolid. Our report suggests that human infections by the recently described Corynebacterium species may not be limited to a specific region, in addition to difficulty of classifying the genus Corynebacterium.


Subject(s)
Corynebacterium Infections , Humans , Corynebacterium Infections/microbiology , RNA, Ribosomal, 16S/genetics , Corynebacterium/genetics , Vancomycin , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
15.
J Korean Med Sci ; 38(10): e73, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-36918027

ABSTRACT

BACKGROUND: The epidemiology of pathogenic bacteria varies according to the socioeconomic status and antimicrobial resistance status. However, longitudinal epidemiological studies to evaluate the changes in species distribution and antimicrobial susceptibility of pathogenic bacteria nationwide are lacking. We retrospectively investigated the nationwide trends in species distribution and antimicrobial susceptibility of pathogenic bacteria over the last 20 years in Korea. METHODS: From 1997 to 2016, annual cumulative antimicrobial susceptibility and species distribution data were collected from 12 university hospitals in five provinces and four metropolitan cities in South Korea. RESULTS: The prevalence of Staphylococcus aureus was the highest (13.1%) until 2012 but decreased to 10.3% in 2016, consistent with the decrease in oxacillin resistance from 76.1% in 2008 to 62.5% in 2016. While the cefotaxime resistance of Escherichia coli increased from 9.0% in 1997 to 34.2% in 2016, E. coli became the most common species since 2013, accounting for 14.5% of all isolates in 2016. Pseudomonas aeruginosa and Acinetobacter baumannii rose to third and fifth places in 2008 and 2010, respectively, while imipenem resistance increased from 13.9% to 30.8% and 0.7% to 73.5% during the study period, respectively. Streptococcus agalactiae became the most common pathogenic streptococcal species in 2016, as the prevalence of Streptococcus pneumoniae decreased since 2010. During the same period, pneumococcal penicillin susceptibility decreased to 79.0%, and levofloxacin susceptibility of S. agalactiae decreased to 77.1% in 2016. CONCLUSION: The epidemiology of pathogenic bacteria has changed significantly over the past 20 years according to trends in antimicrobial resistance in Korea. Efforts to confine antimicrobial resistance would change the epidemiology of pathogenic bacteria and, consequently, the diagnosis and treatment of infectious diseases.


Subject(s)
Anti-Bacterial Agents , Escherichia coli , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Retrospective Studies , Drug Resistance, Bacterial , Bacteria , Microbial Sensitivity Tests , Gram-Negative Bacteria
16.
J Craniofac Surg ; 34(3): e313-e314, 2023 May 01.
Article in English | MEDLINE | ID: mdl-36913559

ABSTRACT

Fractures to the facial bone in the pediatric population often show a different fracture pattern from that of the adult population. In this brief report, the authors share their experience with a nasal bone fracture in a 12-year-old child showing a bizarre fracture pattern, an inside-out displacement of the nasal bone. The authors share the detailed findings of this fracture and describe the method for reducing the fracture back to the proper position.


Subject(s)
Fractures, Multiple , Musculoskeletal Abnormalities , Skull Fractures , Adult , Child , Humans , Skull Fractures/diagnostic imaging , Skull Fractures/surgery , Facial Bones , Nasal Bone/diagnostic imaging , Nasal Bone/injuries
17.
Int J Mol Sci ; 24(2)2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36675245

ABSTRACT

Rheumatoid arthritis (RA) is an inflammatory disease marked by a massive proliferation of synovial cells in the joints. In this study, we investigated the pro-apoptotic effects of docosahexaenoic acid (DHA) in human fibroblast-like synovial cells from RA patients (RA-FLS). An in vitro study using MH7A cells showed that DHA treatment induced caspase-8-dependent apoptosis in a dose-dependent manner and reduced the TNF-α-mediated induction of MMP-9 and IL-1ß. DHA also induced the phosphorylation of eIF2α, the expression of the ER stress markers ATF4 and C/EBP homologous protein (CHOP), and death receptor 5 (DR5). The knockdown of CHOP or DR5 increased cell viability and reduced apoptosis in DHA-treated cells. Furthermore, the knockdown of CHOP reduced DHA-mediated DR5 expression, while the overexpression of CHOP increased DR5 expression. We also found that DHA treatment induced the accumulation of reactive oxygen species (ROS), and pretreatment with the anti-oxidant Tiron effectively abrogated not only the expression of CHOP and DR5, but also DHA-induced apoptosis. Under this condition, cell viability was increased, while PARP-1 cleavage and caspase-8 activation were reduced. All the findings were reproduced in human primary synovial cells obtained from RA patients. These results suggest that the DHA-mediated induction of ROS and CHOP induced apoptosis through the upregulation of DR5 in RA-FLSs, and that CHOP could be used as a therapy for RA.


Subject(s)
Arthritis, Rheumatoid , Docosahexaenoic Acids , Humans , Up-Regulation , Cell Line, Tumor , Reactive Oxygen Species/metabolism , Caspase 8/metabolism , Docosahexaenoic Acids/pharmacology , Apoptosis , Fibroblasts/metabolism , Transcription Factor CHOP/genetics , Transcription Factor CHOP/metabolism
18.
Emerg Infect Dis ; 28(11)2022 11.
Article in English | MEDLINE | ID: mdl-36285883

ABSTRACT

In November 2020, an unusual increase in fungal endophthalmitis cases after cataract surgery was reported to the Korea Disease Control and Prevention Agency, South Korea. We initiated an outbreak investigation to identify the cause. We identified 156 cases nationwide, 62 confirmed and 94 probable. Most case-patients were exposed during surgery to ocular viscoelastic devices (OVDs) from the same manufacturer (company A). We isolated Fusarium spp. from 50 confirmed cases. Molecular identification of 39 fungal isolates from clinical samples and 13 isolates from OVDs confirmed F. oxysporum caused the infections. The risk ratio for fungal endophthalmitis from company A's OVDs was 86.0 (95% CI 27.4-256.9), much higher than risk from other manufacturers' products. We determined this fungal endophthalmitis outbreak was caused by a contaminated lot of OVDs and recommended discontinued use of this product. Early recognition of outbreaks and joint responses from related government agencies can reduce risk for fungal endophthalmitis.


Subject(s)
Cataract Extraction , Cataract , Endophthalmitis , Eye Infections, Fungal , Humans , Cataract Extraction/adverse effects , Endophthalmitis/etiology , Endophthalmitis/microbiology , Eye Infections, Fungal/epidemiology , Eye Infections, Fungal/complications , Eye Infections, Fungal/microbiology , Disease Outbreaks
19.
Antimicrob Agents Chemother ; 66(11): e0088922, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36226945

ABSTRACT

We investigated the evolution of fluconazole resistance mechanisms and clonal types of Candida parapsilosis isolates from a tertiary care hospital in South Korea. A total of 45 clinical isolates, including 42 collected between 2017 and 2021 and 3 collected between 2012 and 2013, were subjected to antifungal susceptibility testing, sequencing of fluconazole resistance genes (ERG11, CDR1, TAC1, and MRR1), and microsatellite typing. Twenty-two isolates carried Y132F (n = 21; fluconazole MIC = 2 to >256 mg/L) or Y132F+R398I (n = 1; fluconazole MIC = 64 mg/L) in ERG11 and four isolates harbored N1132D in CDR1 (fluconazole MIC = 16 to 64 mg/L). All 21 Y132F isolates exhibited similar microsatellite profiles and formed a distinct group in the dendrogram. All four N1132D isolates displayed identical microsatellite profiles. Fluconazole MIC values of the Y132F isolates varied depending on their MRR1 mutation status (number of isolates, year of isolation, and MIC): K177N (n = 8, 2012 to 2020, 2 to 8 mg/L); K177N + heterozygous G982R (n = 1, 2017, 64 mg/L); K177N + heterozygous S614P (n = 2, 2019 to 2020, 16 mg/L); and K177N + homozygous S614P (n = 10, 2020 to 2021, 64 to > 256 mg/L). Our study revealed that Y132F in ERG11 and N1132D in CDR1 were the major mechanisms of fluconazole resistance in C. parapsilosis isolates. Furthermore, our results suggested that the clonal evolution of Y132F isolates persisting and spreading in hospital settings for several years occurred with the acquisition of heterozygous or homozygous MRR1 mutations associated with a gradual increase in fluconazole resistance.


Subject(s)
Candida parapsilosis , Fluconazole , Fluconazole/pharmacology , Candida parapsilosis/genetics , Drug Resistance, Fungal/genetics , Tertiary Care Centers , Antifungal Agents/pharmacology , Fungal Proteins/genetics , Microbial Sensitivity Tests
20.
Hum Genomics ; 15(1): 58, 2021 08 28.
Article in English | MEDLINE | ID: mdl-34454617

ABSTRACT

BACKGROUND: Low-pass sequencing (LPS) has been extensively investigated for applicability to various genetic studies due to its advantages over genotype array data including cost-effectiveness. Predicting the risk of complex diseases such as Parkinson's disease (PD) using polygenic risk score (PRS) based on the genetic variations has shown decent prediction accuracy. Although ultra-LPS has been shown to be effective in PRS calculation, array data has been favored to the majority of PRS analysis, especially for PD. RESULTS: Using eight high-coverage WGS, we assessed imputation approaches for downsampled LPS data ranging from 0.5 × to 7.0 × . We demonstrated that uncertain genotype calls of LPS diminished imputation accuracy, and an imputation approach using genotype likelihoods was plausible for LPS. Additionally, comparing imputation accuracies between LPS and simulated array illustrated that LPS had higher accuracies particularly at rare frequencies. To evaluate ultra-low coverage data in PRS calculation for PD, we prepared low-coverage WGS and genotype array of 87 PD cases and 101 controls. Genotype imputation of array and downsampled LPS were conducted using a population-specific reference panel, and we calculated risk scores based on the PD-associated SNPs from an East Asian meta-GWAS. The PRS models discriminated cases and controls as previously reported when both LPS and genotype array were used. Also strong correlations in PRS models for PD between LPS and genotype array were discovered. CONCLUSIONS: Overall, this study highlights the potentials of LPS under 1.0 × followed by genotype imputation in PRS calculation and suggests LPS as attractive alternatives to genotype array in the area of precision medicine for PD.


Subject(s)
Genetic Predisposition to Disease , Multifactorial Inheritance/genetics , Parkinson Disease/genetics , Whole Genome Sequencing/statistics & numerical data , Adult , Aged , Chromosome Mapping , Female , Genome-Wide Association Study , Genotype , Humans , Male , Middle Aged , Parkinson Disease/pathology , Polymorphism, Single Nucleotide/genetics , Risk Factors
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