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1.
J Med Virol ; 96(3): e29536, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38488495

ABSTRACT

Following the worldwide surge in mpox (monkeypox) in 2022, cases have persisted in Asia, including South Korea, and sexual contact is presumed as the predominant mode of transmission, with a discernible surge in prevalence among immunocompromised patients. Drugs such as tecovirimat can result in drug-resistant mutations, presenting obstacles to treatment. This study aimed to ascertain the presence of tecovirimat-related resistant mutations through genomic analysis of the monkeypox virus isolated from a reported case involving prolonged viral shedding in South Korea. Here, tecovirimat-resistant mutations, previously identified in the B.1 clade, were observed in the B.1.3 clade, predominant in South Korea. These mutations exhibited diverse patterns across different samples from the same patient and reflected the varied distribution of viral subpopulations in different anatomical regions. The A290V and A288P mutant strains we isolated hold promise for elucidating these mechanisms, enabling a comprehensive analysis of viral pathogenesis, replication strategies, and host interactions. Our findings imply that acquired drug-resistant mutations, may present a challenge to individual patient treatment. Moreover, they have the potential to give rise to transmitted drug-resistant mutations, thereby imposing a burden on the public health system. Consequently, the meticulous genomic surveillance among immunocompromised patients, conducted in this research, assumes paramount importance.


Subject(s)
Benzamides , Immunocompromised Host , Humans , Virus Shedding , Isoindoles , Mutation , Republic of Korea
2.
Viruses ; 16(1)2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38257807

ABSTRACT

Ticks are important vectors of the tick-borne encephalitis virus (TBEV). In Kyrgyzstan, the livestock farming trade and nomadic lifestyle enable tick-borne diseases to be imported from neighboring countries, but there are few relevant studies. In this study, we collected 40 ticks from cattle in Kyrgyzstan. Molecular marker analysis identified the ticks as Ixodes persulcatus (97.5%; n = 39) and Haemaphysalis punctata (2.5%; n = 1). Real-time PCR screening revealed two ticks to be positive for TBEV, but only one tick was amplified using nested PCR targeting the TBEV envelope (E) and non-structure 5 (NS5) gene. The obtained sequences belonged to the TBEV Siberian subtype and phylogenetic tree analysis results confirmed that the virus was related to the Bosnia strain. We also performed next-generation sequencing, which confirmed the TBEV Siberian subtype. Continuous research and surveillance of TBEV in Kyrgyzstan are required to provide further information on tick-borne diseases.


Subject(s)
Encephalitis Viruses, Tick-Borne , Ixodes , Tick-Borne Diseases , Cattle , Animals , Phylogeny , Encephalitis Viruses, Tick-Borne/genetics , Kyrgyzstan/epidemiology , Real-Time Polymerase Chain Reaction
3.
Microbiol Resour Announc ; 11(11): e0085322, 2022 Nov 17.
Article in English | MEDLINE | ID: mdl-36250860

ABSTRACT

We report the complete genome sequence of the monkeypox virus strain MPXV-ROK-P1-2022, isolated from the first patient diagnosed with monkeypox in the Republic of Korea in June 2022. The virus was fully sequenced on the Illumina MiSeq instrument, and the phylogenetic tree showed that the strain belongs to lineage B.1.1.

4.
Osong Public Health Res Perspect ; 13(4): 308-311, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36097753

ABSTRACT

OBJECTIVES: Monkeypox outbreaks in nonendemic countries have been reported since early May 2022. The first case of monkeypox in the Republic of Korea was confirmed in a patient who traveled to Europe in June 2022, and an attempt was made to isolate and identify the monkeypox virus (MPXV) from the patient's specimens. METHODS: Clinical specimens from the patient were inoculated in Vero E6 cells. The isolated virus was identified as MPXV by the observation of cytopathic effects on Vero E6 cells, transmission electron microscopy, conventional polymerase chain reaction (PCR), and sequencing of PCR products. RESULTS: Cytopathic effects were observed in Vero E6 cells that were inoculated with skin lesion swab eluates. After multiple passages from the primary culture, orthopoxvirus morphology was observed using transmission electron microscopy. In addition, both MPXV-specific (F3L and ATI) and orthopoxvirus-specific genes (A39R, B2R, and HA) were confirmed by conventional PCR and Sanger sequencing. CONCLUSION: These results indicate the successful isolation and identification of MPXV from the first patient in the Republic of Korea. The isolated virus was named MPXV-ROK-P1-2022.

5.
Microbiol Resour Announc ; 11(2): e0071921, 2022 Feb 17.
Article in English | MEDLINE | ID: mdl-35084225

ABSTRACT

Francisella tularensis is the etiological agent of the zoonosis tularemia. Here, we report the draft genome sequence of F. tularensis subsp. holarctica H0001, which was isolated from a tularemia patient in the Republic of Korea.

6.
Heliyon ; 7(10): e08170, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34660919

ABSTRACT

To understand the origin of variants and their evolutionary history in the early stage of the COVID-19 pandemic, time-scaled phylogenetic and gene variation analyses were performed. The mutation patterns and evolution characteristics were examined using the Bayesian Evolutionary Analysis Sampling Trees (BEAST) with 349 whole-genome sequences available by March 2020. The results revealed five phylogenetic clusters (Groups A-E), with 408 nucleotide variants. The mutations including the deletion of three nucleotides underwent various and complicated changes in the whole genome over time, while some frequency or transient mutations were also observed. Phylogenetic analysis demonstrated that SARS-CoV-2 originated from China and was transmitted to other Asian countries, followed by North America and Europe. This study could help to comprehensively understand the evolutionary characteristics of SARS-CoV-2 with a special emphasis on its global variation patterns.

7.
Arch Microbiol ; 203(10): 6053-6060, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34562146

ABSTRACT

A Gram-positive, aerobic, rod-shaped bacterium, designated as strain 1605-214T, was isolated from the blood sample of a patient with cholangitis. Based on its 16S rRNA gene sequence, the strain 1605-214T belonged to the genus Cohnella and exhibited 97.9% sequence identity with Cohnella luojiensis DSM 24270T (GQ214052). DNA-DNA hybridization, digital DNA-DNA hybridization, and average nucleotide identity values between the two species were 23% ± 1.9, 21.1%, and 77.2%, respectively. The cellular fatty acids of strain 1605-214T were mainly comprised of anteiso-C15:0 (36.1%), iso-C16:0 (16.5%), and C16:0 (15.1%). The predominant quinone was menaquinone-7; predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, and aminophospholipid-1. The cell wall peptidoglycan of strain 1605-214T contained meso-diaminopimelic acid. DNA G + C content of strain 1605-214T was 50.6 mol%. 5187 genes out of a total of 5413 (94.6%) were assigned putative functions using eggNOG v5.0. Based on genotypic characteristics and genomic sequence analysis results, strain 1605-214T was confirmed to represent a novel species of genus Cohnella, for which the name Cohnella cholangitidis sp. nov., was proposed.


Subject(s)
Fatty Acids , Phospholipids , Bacillales , Bacterial Typing Techniques , DNA, Bacterial/genetics , Fatty Acids/analysis , Humans , Phospholipids/analysis , Phylogeny , RNA, Ribosomal, 16S/genetics , Republic of Korea , Sequence Analysis, DNA , Vitamin K 2
8.
Ann Lab Med ; 41(5): 489-492, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-33824238

ABSTRACT

Botulism is a neuroparalytic disease caused by a neurotoxin produced by Clostridium botulinum. This study aimed to genetically characterize C. botulinum strain isolated from the first case of infant botulism in Korea reported on June 17, 2019. We isolated C. botulinum strain CB-27 from a stool sample of the patient and analyzed the toxin types and toxin gene cluster compositions of the strain using a mouse bioassay, real-time PCR, and genome sequencing. Toxin gene cluster analysis showed that strain CB-27 possesses a C. botulinum neurotoxin type A harboring an unexpressed B gene. Although the nucleotide and amino acid sequences of toxin genes as well as the toxin gene cluster arrangements in strain CB-27 were identical to those of the known strain CDC_69094, the total nucleotide sequences of the toxin gene clusters of CB-27 differed from those of CDC_69094 by 0.47%, indicating genetic diversity of toxin gene clusters of CB-27 among other previously reported C. botulinum strains. To our knowledge, this is the first description of a C. botulinum strain with two separate toxin gene clusters in Korea.


Subject(s)
Botulinum Toxins , Botulism , Clostridium botulinum , Botulinum Toxins/genetics , Botulism/diagnosis , Clostridium botulinum/genetics , Humans , Infant , Phylogeny , Republic of Korea
9.
Microbiol Resour Announc ; 9(9)2020 Feb 27.
Article in English | MEDLINE | ID: mdl-32107302

ABSTRACT

In this study, the complete genome sequences of Micrococcus luteus strains NCCP 15687 and NCCP 16831 were determined and deposited in the National Culture Collection for Pathogens (NCCP) of South Korea. Genomic DNA was isolated from blood samples from patients infected with M. luteus.

10.
PLoS One ; 11(3): e0151064, 2016.
Article in English | MEDLINE | ID: mdl-26954507

ABSTRACT

High-throughput sequencing can produce hundreds of thousands of 16S rRNA sequence reads corresponding to different organisms present in the environmental samples. Typically, analysis of microbial diversity in bioinformatics starts from pre-processing followed by clustering 16S rRNA reads into relatively fewer operational taxonomic units (OTUs). The OTUs are reliable indicators of microbial diversity and greatly accelerate the downstream analysis time. However, existing hierarchical clustering algorithms that are generally more accurate than greedy heuristic algorithms struggle with large sequence datasets. To keep pace with the rapid rise in sequencing data, we present CLUSTOM-CLOUD, which is the first distributed sequence clustering program based on In-Memory Data Grid (IMDG) technology-a distributed data structure to store all data in the main memory of multiple computing nodes. The IMDG technology helps CLUSTOM-CLOUD to enhance both its capability of handling larger datasets and its computational scalability better than its ancestor, CLUSTOM, while maintaining high accuracy. Clustering speed of CLUSTOM-CLOUD was evaluated on published 16S rRNA human microbiome sequence datasets using the small laboratory cluster (10 nodes) and under the Amazon EC2 cloud-computing environments. Under the laboratory environment, it required only ~3 hours to process dataset of size 200 K reads regardless of the complexity of the human microbiome data. In turn, one million reads were processed in approximately 20, 14, and 11 hours when utilizing 20, 30, and 40 nodes on the Amazon EC2 cloud-computing environment. The running time evaluation indicates that CLUSTOM-CLOUD can handle much larger sequence datasets than CLUSTOM and is also a scalable distributed processing system. The comparative accuracy test using 16S rRNA pyrosequences of a mock community shows that CLUSTOM-CLOUD achieves higher accuracy than DOTUR, mothur, ESPRIT-Tree, UCLUST and Swarm. CLUSTOM-CLOUD is written in JAVA and is freely available at http://clustomcloud.kopri.re.kr.


Subject(s)
Cluster Analysis , Environmental Microbiology , RNA, Ribosomal, 16S/genetics , Software , Computational Biology/methods , Humans , Reproducibility of Results , Workflow
11.
Radiat Oncol J ; 30(3): 99-107, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23170288

ABSTRACT

PURPOSE: The aim of this study was to identify clinical predictive factors for tumor response after preoperative chemoradiotherapy (CRT) in rectal cancer. MATERIALS AND METHODS: The study involved 51 patients who underwent preoperative CRT followed by surgery between January 2005 and February 2012. Radiotherapy was delivered to the whole pelvis at a dose of 45 Gy in 25 fractions, followed by a boost of 5.4 Gy in 3 fractions to the primary tumor with 5 fractions per week. Three different chemotherapy regimens were used (5-fluorouracil and leucovorin, capecitabine, or tegafur/uracil). Tumor responses to preoperative CRT were assessed in terms of tumor downstaging and pathologic complete response (ypCR). Statistical analyses were performed to identify clinical factors associated with pathologic tumor response. RESULTS: Tumor downstaging was observed in 28 patients (54.9%), whereas ypCR was observed in 6 patients (11.8%). Multivariate analysis found that predictors of downstaging was pretreatment relative lymphocyte count (p = 0.023) and that none of clinical factors was significantly associated with ypCR. CONCLUSION: Pretreatment relative lymphocyte count (%) has a significant impact on the pathologic tumor response (tumor downstaging) after preoperative CRT for locally advanced rectal cancer. Enhancement of lymphocyte-mediated immune reactions may improve the effect of preoperative CRT for rectal cancer.

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