Genetic variations underlying aminoglycoside resistance in antibiotic-induced Mycobacterium intracellulare mutants.

Mycobacterium avium complex (MAC) is an emerging pathogen leading to public health concerns in developing and developed countries, particularly among immunocompromised individuals and patients with structural lung diseases. Current clinical guidelines recommend combination antibiotic therapy for treating MAC pulmonary disease (MAC-PD). However, the rising prevalence of antibiotic resistance poses significant challenges, including treatment failure and clinical recurrence.

Prominent transcriptomic changes in Mycobacterium intracellulare under acidic and oxidative stress.

Background: Mycobacterium avium complex (MAC), including Mycobacterium intracellulare is a member of slow-growing mycobacteria and contributes to a substantial proportion of nontuberculous mycobacterial lung disease in humans affecting immunocompromised and elderly populations. Adaptation of pathogens in hostile environments is crucial in establishing infection and persistence within the host. However, the sophisticated cellular and molecular mechanisms of stress response in M.

ANCA: artificial nucleic acid circuit with argonaute protein for one-step isothermal detection of antibiotic-resistant bacteria.

Endonucleases have recently widely used in molecular diagnostics. Here, we report a strategy to exploit the properties of Argonaute (Ago) proteins for molecular diagnostics by introducing an artificial nucleic acid circuit with Ago protein (ANCA) method. The ANCA is designed to perform a continuous autocatalytic reaction through cross-catalytic cleavage of the Ago protein, enabling one-step, amplification-free, and isothermal DNA detection.

sp. nov., isolated from human blood.

An obligate anaerobic, Gram-negative, rod-shaped and non-spore-forming bacterium, designated as strain GYB001, was isolated from the blood of a patient with a sigmoid colon perforation. Taxonomic characterization of the novel isolate was performed using a polyphasic approach. A phylogenetic analysis based on 16S rRNA gene and whole genome sequences revealed that GYB001 represented a member of the genus , in the family .

Fatal Primary Amebic Meningoencephalitis due to : The First Imported Case in Korea.

Primary amebic meningoencephalitis (PAM) is a rare, but almost always fatal, central nervous system infection caused by , which are thermophilic free-living amoeba. Here, we report the first case of PAM detected in South Korea, probably imported from Thailand. Despite antimicrobial treatment for infection with a combination of intravenous liposomal amphotericin B, fluconazole, azithromycin, and oral rifampin, the patient died 13 days after the onset of symptoms.

A novel repeat sequence-based PCR (rep-PCR) using specific repeat sequences of as a DNA fingerprinting.

Repetitive sequence-based PCR (rep-PCR) is a potential epidemiological technique that can provide high-throughput genotype fingerprints of heterogeneous strains rapidly. Previously published rep-PCR primers, which are based on nucleotide sequences of Gram-negative bacteria may have low specificity for mycobacteria. Moreover, it was difficult to ensure the continuity of the study after the commercial rep-PCR kit was discontinued.

Analysis of treatment pattern of anti-dementia medications in newly diagnosed Alzheimer's dementia using OMOP CDM.

Anti-dementia medications are widely prescribed to patients with Alzheimer's dementia (AD) in South Korea. This study investigated the pattern of medical management in newly diagnosed patients with AD using a standardized data format-the Observational Medical Outcome Partnership Common Data Model from five hospitals. We examined the anti-dementia treatment patterns from datasets that comprise > 5 million patients during 2009-2019.

The novel HLA-B*40:489 allele identified in a Korean hematopoietic stem cell donor.

Single nucleotide substitution in codon 140 of HLA-B*40:02:01:01 results in the novel HLA-B*40:489 allele.

Identification of Nontuberculous Mycobacteria in Patients with Pulmonary Diseases in Gyeongnam, Korea, Using Multiplex PCR and Multigene Sequence-Based Analysis.

Background: Nontuberculous mycobacteria (NTM) are widely present in environments, such as soil and water, and have recently been recognized as important pathogenic bacteria. The incidence of NTM-related infections is steadily increasing. As the diagnosis and treatment of NTM infection should be distinguished from tuberculosis, and the treatment should be specific to the species of NTM acquired, accurate species identification is required.

Fusobacterium nucleatum in biopsied tissues from colorectal cancer patients and alcohol consumption in Korea.

The roles of individual bacteria and their relationship in the development of colorectal cancer (CRC) remain unclear. We aimed to determine the prevalence of CRC-associated bacteria using quantitative real-time PCR (qPCR) or 16S rRNA analysis and the statistical correlations of patient demographics and clinical characteristics comprising alcohol consumption with CRC-associated bacteria. We determined the prevalence of five CRC-associated bacterial species in 38 CRC patients (39 samples) and 21 normal individuals using qPCR, and the relative abundance of bacterial taxa in the gut microbiome was assessed using 16S rRNA analysis.

In Vitro Activity of a Novel Siderophore-Cephalosporin, GT-1 and Serine-Type β-Lactamase Inhibitor, GT-055, against , and spp. Panel Strains.

This study investigates GT-1 (also known as LCB10-0200), a novel-siderophore cephalosporin, inhibited multidrug-resistant (MDR) Gram-negative pathogen, via a Trojan horse strategy exploiting iron-uptake systems. We investigated GT-1 activity and the role of siderophore uptake systems, and the combination of GT-1 and a non-β-lactam β-lactamase inhibitor (BLI) of diazabicyclooctane, GT-055, (also referred to as LCB18-055) against molecularly characterised resistant , and spp. isolates.

Evaluation of Xpert Carba-R Assay v.2 to Detect Carbapenemase Genes in Two Hospitals in Korea.

Background: As the spread of carbapenemase-producing poses a critical threat to public health, rapid detection of carbapenemase genes is urgently required for prompt initiation of appropriate antimicrobial therapy and infection control. We evaluated the performance of Xpert Carba-R v.2 (Cepheid, USA) compared with that of culture-based conventional PCR.

Performance evaluation of a new matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, ASTA MicroIDSys system, in bacterial identification against clinical isolates of anaerobic bacteria.

Introduction: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been introduced for bacterial identification. The ASTA MicroIDSys system (ASTA, Suwon, Korea) is a new MALDI-TOF MS system developed for species identification of microorganisms. We evaluated the performance of MicroIDSys against clinical isolates of anaerobic bacteria.

An agar plate-based modified carbapenem inactivation method (p-mCIM) for detection of carbapenemase-producing Enterobacteriaceae.

Detecting carbapenemase-producing Enterobacteriaceae (CPE) has become increasingly difficult due to the emergence of diverse enzymes. The aim of the study was to evaluate an agar plate-based modified carbapenem inactivation method (p-mCIM) for detection of CPE. Stock strains and clinical isolates of CPE were used to evaluate the p-mCIM.