Biology subjects

Kwon, H.

Publications and source records attributed to Kwon, H..

3 recordsLinked to original sources

bioRxiv2018

Loop-mediated isothermal amplification assay for Enterococcus sp., E. coli and S. aureus in chicken

Bacterial chondronecrosis with osteomyelitis (BCO) is a major cause of lameness in broiler chicken, and results in serious economic losses worldwide. Although the pathogenesis mechanism leading to lameness is not entirely understood, some strains of Enterococcus sp., avian pathogenic Escherichia coli, or Staphylococcus aureus have been long recognized as important causative pathogens. To prevent the progression of Enterococcus sp., avian pathogenic E. coli, or S. aureus infections, we developed rapid, sensitive, and convenient diagnostic assays using loop-mediated isothermal amplification (LAMP). Entero-Common-LAMP assays were developed for a simultaneous detection of eight Enterococcus species. To target specific microorganisms, seven Entero-Specific-LAMP assays for E. faecalis, E. faecium, E. hirae, E. gallinarum, E. avium, E. durans and E. cecorum, and E. coli-LAMP and S. aureus-LAMP assays, were developed. Considering the prevalence and economic impact of Enterococcus sp., E. coli, and S. aureus, the developed ten different LAMP assays have a considerable potential as routine diagnostic methods in the field or in resource-limited environments.

microbiology↗

bioRxiv2017

Heartfelt Face Perception via the Interoceptive Pathway - a MEG study

The somatic marker hypothesis proposes that the cortical representation of visceral signals is a crucial component of emotion processing. No previous study has investigated the causal relationships among brain regions that process visceral information during emotional perception. In this magnetoencephalography study of 32 healthy subjects, heartbeat-evoked potentials (HEPs), which reflect the cortical processing of heartbeats, were modulated by the perception of a sad face. The modulation effect was localized to the prefrontal cortices, the globus pallidus, and an interoceptive network including the right anterior insula (RAI) and anterior cingulate cortex (RACC). Importantly, our Granger causality analysis provides the first evidence for increased causal flow of heartbeat information from the RAI to the RACC during sad face perception. Moreover, this HEP modulation effect was neither an artefact nor an effect of visual-evoked potentials. These findings provide important progress in the understanding of brain-body interactions during emotion processing.

neuroscience↗

bioRxiv2017

Comparison of Principal Component Analysis and t-Stochastic Neighbor Embedding with Distance Metric Modifications for Single-cell RNA-sequencing Data Analysis

Recent developments in technological tools such as next generation sequencing along with peaking interest in the study of single cells has enabled single-cell RNA-sequencing, in which whole transcriptomes are analyzed on a single-cell level. Studies, however, have been hindered by the ability to effectively analyze these single cell RNA-seq datasets, due to the high-dimensional nature and intrinsic noise in the data. While many techniques have been introduced to reduce dimensionality of such data for visualization and subpopulation identification, the utility to identify new cellular subtypes in a reliable and robust manner remains unclear. Here, we compare dimensionality reduction visualization methods including principle component analysis and t-stochastic neighbor embedding along with various distance metric modifications to visualize single-cell RNA-seq datasets, and assess their performance in identifying known cellular subtypes. Our results suggest that selecting variable genes prior to analysis on single-cell RNA-seq data is vital to yield reliable classification, and that when variable genes are used, the choice of distance metric modification does not particularly influence the quality of classification. Still, in order to take advantage of all the gene expression information, alternative methods must be used for a reliable classification.

bioinformatics↗