The First Report of Nadifloxacin-Resistant Propionibacterium acnes Isolated from a Patient

Hyunjin Hong,Hye-Ran Nam,Gwang-Yeol Joh,Yeonhee Lee 서울여자대학교 자연과학연구소 2012 자연과학연구논문집 Vol.24 No.-

This is the first report of nadifloxacin-resistant Propionibacterium acnes SKA109. SKA109 was isolated from a patient who was never treated with nadifloxacin before. Its MICs to various quinolones were 8 to 16 fold higher than MICs of the type strain. Especially P. acnes SKA109 was resistant to nadifloxacin which was newly introduced in acne treatment and have been prescribed in Korea since 2008. 이 보고는 나디플록사신 내성 Propionibacterium acnes에 관한 첫 보고이다. Propionibacterium acnes SKA109는 나디플록사신 치료를 받은 경험이 없는 환자로부터 분리하였으며, 퀴놀론 항생제에 대한 MIC가 8-16으로 매우 높았고, 특히 나디플록사신에 강한 내성을 보였다. 나디플록사신은 2008년 이후 한국에서 사용되었으며 그 이전에는 사용된 적이 없는 새로운 항생제이다.

Transfer of Antimicrobial-Resistant Escherichia coli and Resistance Genes in a Child Care Center

( Hyunjin Hong ),( Yeonhee Lee ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.3

Several reports describe antimicrobial-resistance transfer among children and the community in outbreak situations, but transfer between a child and a caregiver has not been examined in child care facilities under normal circumstances. We investigated the transfer of antimicrobial-resistance genes, resistant bacteria, or both among healthy children and teachers. From 2007 to 2009, 104 Escherichia coli isolates were obtained from four teachers and 38 children in a child care center. Twenty-six cephem-resistant isolates were obtained from children in 2007 and 2008. In 2009, cephem-resistant isolates were detected in children as well as a teacher. Nalidixic acid-resistant isolates from the same teacher for 3 years showed low similarity (<50%) to each other. However, an isolate from a teacher in 2007 and another from a child in 2008 showed high similarity (87%). Pulsed-field gel electrophoresis revealed 100% similarity for four isolates in 2007 and one isolate in 2008, and also similarity among seven isolates carrying the virulence gene (CNF1). This study yielded the following findings: (1) a gene for extended-spectrum β-lactamase was transferred from a child to other children and a teacher; (2) a nalidixic acid-resistant isolate was transferred from a teacher to a child; and (3) a virulent bacterium was transferred between children.

멀티프로세서상의 에너지 소모를 고려한 동적 전압 스케일링 및 전력 셧다운을 이용한 태스크 스케줄링

김현진(HyunJin Kim),홍혜정(Hyejeong Hong),김홍식(Hong-Sik Kim),강성호(Sungho Kang) 대한전자공학회 2009 電子工學會論文誌-SD (Semiconductor and devices) Vol.46 No.7

멀티프로세서가 임베디드 시스템에서 널리 쓰임에 따라 지원되는 전력 최소화 기법을 이용하여태스크를 수행하기 위해 필요한 에너지의 소모량을 줄여야 할 필요성이 대두된다. 본 논문은 동적 전압 스케일링 및 전력 셧다운을 이용하여 에너지 소모를 최소화 하는 태스크 스케줄링 알고리즘을 멀티프로세서 환경을 위해 제안하였다. 제안된 알고리즘에서는 전력 셧다운시의 에너지 및 타이밍 오버헤드를 고려하여 반복적으로 태스크 할당 및 태스크 순서화를 수행한다. 제안된 반복적인 태스크 스케줄링을 통해 전체 에너지 소모를 줄이는 가장 좋은 해를 얻을 수 있었다. 전체 에너지 소모는 리니어 프로그래밍 모델 및 전력 셧다운의 임계 시간을 고려하여 계산되었다. 실제 어플리케이션으로부터 추출된 표준 태스크 그래프에 기반을 둔 실험결과를 통해 하드웨어 자원 및 시간제한에 따른 에너지 소모 관계를 분석하였다. 실험 결과를 볼 때 제안된 알고리즘은 기존의 우선권 기반의 태스크 스케줄링에 대해서 의미 있는 성능 향상을 얻을 수 있었다. As multiprocessors have been widely adopted in embedded systems, task computation energy consumption should be minimized with several low power techniques supported by the multiprocessors. This paper proposes an energy-aware task scheduling algorithm that adopts both dynamic voltage scaling and power shutdown in multiprocessor environments. Considering the timing and energy overhead of power shutdown, the proposed algorithm performs an iterative task assignment and task ordering for multiprocessor systems. In this case, the iterative priority-based task scheduling is adopted to obtain the best solution with the minimized total energy consumption. Total energy consumption is calculated by considering a linear programming model and threshold time of power shutdown. By analyzing experimental results for standard task graphs based on real applications, the resource and timing limitations were analyzed to maximize energy savings. Considering the experimental results, the proposed energy-aware task scheduling provided meaningful performance enhancements over the existing priority-based task scheduling approaches.

리스트 스케줄링을 통한 Coarse-Grained 재구성 구조의 맵핑 알고리즘 개발

김현진(HyunJin Kim),홍혜정(Hyejeong Hong),김홍식(Hong-Sik Kim),강성호(Sungho Kang) 대한전자공학회 2009 電子工學會論文誌-SD (Semiconductor and devices) Vol.46 No.6

재구성 구조를 위한 자동화된 툴의 개발에 있어서 명령들을 재구성 구조에 맵핑하기 위한 알고리즘의 개발은 가장 중요한 부분 중의 하나이다. 본 논문에서는 리소스가 한정된 Coarse-Grained 재구성 구조에 명령들을 맵핑하기 위한 알고리즘을 개발하고 이를 위한 휴리스틱을 제시하였다. 제안된 알고리즘에서는 하드웨어 리소스 사용에 대한 명령 할당과 라우팅 경로 할당을 사이클 기반의 타이밍 모델을 통해서 동시에 고려하였다. 제안된 알고리즘은 통신에 사용되는 리소스의 사용 및 전역 메모리 접근을 리스트 스케줄링을 기반으로 최소화한다. 리스트 스케줄링에서 맵핑되어야 할 명령들은 대상 어플리케이션의 데이터 플로우의 일반적인 특성들로 우선순위가 결정되게 된다. 제안된 맵핑 알고리즘의 대한 평가를 통해서 볼 때 전역 메모리 자원의 소모 및 수행 시간면에서 상당한 성능향상을 얻을 수 있었다. For the success of the reconfigurable computing, the algorithm for mapping operations onto coarse-grained reconfigurable architecture is very important. This paper proposes a resource-aware mapping system for the coarse-grained reconfigurable architecture and its own underlying heuristic algorithm. The operation assignment and the routing path allocation are simultaneously performed with a cycle-accurate time-exclusive resource model. The proposed algorithm minimizes the communication resource usage and the global memory access with the list scheduling heuristic. The operation to be mapped are prioritized with general properties of data flow. The evaluations of the proposed algorithm show that the performance is significantly enhanced in several benchmark applications.

한강에서 분리된 Extended Spectrum β-Lactamase (ESBL) 대장균의 내성 연구

홍현진,천정녀,이연희 서울여자대학교 자연과학연구소 2003 자연과학연구논문집 Vol.15 No.-

Compared to the number of study with extended spectrum ,β-lactamases (ESBLs)producing clinical isolates, environmental ESBL-producers have not been extensively studied. To investigate environmental ESBL-producing Escherichia coli, twenty-two cephalothin-resistant E.coli were isolated from Han-river in Seoul, Korea. These isolates were resistant to ampicillin, cephalothin, and gentamicin and fourteen isolates among these were resistant to norfloxacin, too. All of these isolates produce AmpC and CMY, OXA, or TEM as determined by isoelectric point focusing gel electrophoresis and PCR. One isolate (No. 57-214) producing AmpC and OXA was resistant to all antibiotics (ampicillin, cephalothin, norfloxacin, gentamycin, cefotaxime, ceftazidime) tested in this study. Six isolates including isolate No. 57-214 could adhere to T24 human bladder cells and these isolates were not related to each other as shown with RAPD. ESBL을 생산하는 임상 균주에 대한 연구는 많은 연구가 진행되고 있는 데 비해 환경 균주에 대한 연구는 널리 진행되고 있지 않다. 환경에서 분리한 ESBL을 생산하는 E.coli를 연구하기 위해 서울의 한강에서 22개의 cephalothin 내성 E.coli를 분리하였다. 한강에서 분리한 22균주 모두 ampicillin, cephalothothin 그리고 gentamicin에 내성이었고, 이중 14 균주가 norfloxacin 에 내성이었다. PCR을 통하여 모든 균주가 AmpC와 CMY, OXA 또는 TEM을 가지고 있음을 확인하였고, 이들의 pI는 isoelectricfocusing을 통해 측정하였다. 특히, AmpC와 OXA를 생산하는 No.57-214는 본 실험에 사용한 모든 항생제에 내성을 보였다 (ampicillin, cephalothin, norfloxacin). 이들 균주들은 randomly amplified polymorphic DNA (RAPD) 를 이용하여 연관도를 분석한 결과 각각 모두 다른 균주임을 확인하였다.

A Lossless Color Image Compression Architecture Using a Parallel Golomb-Rice Hardware CODEC

Hong-Sik Kim,Joohong Lee,Hyunjin Kim,Sungho Kang,Woo Chan Park IEEE 2011 IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDE Vol.21 No.11

<P>In this paper, a high performance lossless color image compression and decompression architecture to reduce both memory requirement and bandwidth is proposed. The proposed architecture consists of differential-differential pulse coded modulation (DDPCM) and Golomb-Rice coding. The original image frame is organized as m by n sub-window arrays, to which DDPCM is applied to produce one seed and m × n - 1 pieces of differential data. Then the differential data are encoded using the Golomb-Rice algorithm to produce losslessly compressed data. According to the experimental results on benchmark images, the proposed architecture can guarantee high enough compression rate and throughput to perform real-time lossless CODEC operations with a reasonable hardware area.</P>

Two-step deep neural network for segmentation of deep white matter hyperintensities in migraineurs

Hong, Jisu,Park, Bo-yong,Lee, Mi Ji,Chung, Chin-Sang,Cha, Jihoon,Park, Hyunjin Elsevier 2020 Computer methods and programs in biomedicine Vol.183 No.-

<P><B>Abstract</B></P> <P><B>Background and Objective</B></P> <P>Patients with migraine show an increased presence of white matter hyperintensities (WMHs), especially deep WMHs. Segmentation of small, deep WMHs is a critical issue in managing migraine care. Here, we aim to develop a novel approach to segmenting deep WMHs using deep neural networks based on the U-Net.</P> <P><B>Methods</B></P> <P>148 non-elderly subjects with migraine were recruited for this study. Our model consists of two networks: the first identifies potential deep WMH candidates, and the second reduces the false positives within the candidates. The first network for initial segmentation includes four down-sampling layers and four up-sampling layers to sort the candidates. The second network for false positive reduction uses a smaller field-of-view and depth than the first network to increase utilization of local information.</P> <P><B>Results</B></P> <P>Our proposed model segments deep WMHs with a high true positive rate of 0.88, a low false discovery rate of 0.13, and F<SUB>1</SUB> score of 0.88 tested with ten-fold cross-validation. Our model was automatic and performed better than existing models based on conventional machine learning.</P> <P><B>Conclusion</B></P> <P>We developed a novel segmentation framework tailored for deep WMHs using U-Net. Our algorithm is open-access to promote future research in quantifying deep WMHs and might contribute to the effective management of WMHs in migraineurs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Deep learning approach for segmenting deep white matter hyperintensity is proposed. </LI> <LI> Two-step approach uses initial segmentation and false positive reduction networks. </LI> <LI> Our approach segmented white matter hyperintensities with good performance. </LI> </UL> </P>

Age-related connectivity differences between attention deficit and hyperactivity disorder patients and typically developing subjects: a resting-state functional MRI study

Hong, Jisu,Park, Bo-yong,Cho, Hwan-ho,Park, Hyunjin Medknow PublicationsMedia Pvt Ltd 2017 Neural regeneration research Vol.12 No.10

<P>Attention deficit and hyperactivity disorder (ADHD) is a disorder characterized by behavioral symptoms including hyperactivity/impulsivity among children, adolescents, and adults. These ADHD related symptoms are influenced by the complex interaction of brain networks which were under explored. We explored age-related brain network differences between ADHD patients and typically developing (TD) subjects using resting state fMRI (rs-fMRI) for three age groups of children, adolescents, and adults. We collected rs-fMRI data from 184 individuals (27 ADHD children and 31 TD children; 32 ADHD adolescents and 32 TD adolescents; and 31 ADHD adults and 31 TD adults). The Brainnetome Atlas was used to define nodes in the network analysis. We compared three age groups of ADHD and TD subjects to identify the distinct regions that could explain age-related brain network differences based on degree centrality, a well-known measure of nodal centrality. The left middle temporal gyrus showed significant interaction effects between disease status (<I>i.e</I>., ADHD or TD) and age (<I>i.e</I>., child, adolescent, or adult) (<I>P</I> < 0.001). Additional regions were identified at a relaxed threshold (<I>P</I> < 0.05). Many of the identified regions (the left inferior frontal gyrus, the left middle temporal gyrus, and the left insular gyrus) were related to cognitive function. The results of our study suggest that aberrant development in cognitive brain regions might be associated with age-related brain network changes in ADHD patients. These findings contribute to better understand how brain function influences the symptoms of ADHD.</P>

Indocyanine green-loaded hollow mesoporous silica nanoparticles as an activatable theranostic agent

Hong, Suk ho,Kim, Hyunjin,Choi, Yongdoo IOP 2017 Nanotechnology Vol.28 No.18

<P>Here we report indocyanine green (ICG)-loaded hollow mesoporous silica nanoparticles (ICG@HMSNP) as an activatable theranostic platform. Near-infrared fluorescence and singlet oxygen generation of ICG@HMSNP was effectively quenched (i.e. turned off) in its native state because of the fluorescence resonance energy transfer between ICG molecules. Therefore, ICG@HMSNP was nonfluorescent and nonphototoxic in the extracellular region. After the nanoparticles entered the cancer cells via endocytosis, they became highly fluorescent and phototoxic. In addition, intracellular uptake of ICG@HMSNP was 2.75 times higher than that of free ICG, resulting in an enhanced phototherapy of cancer.</P>

2006년 돼지에서 분리한 대장균의 내성 현황

홍현진,이민영,이연희 서울여자대학교 자연과학연구소 2006 자연과학연구논문집 Vol.18 No.-

현재 축산 농가에서의 항생제의 오ㆍ남용은 매우 심각한 수준이다. 사료 배합용이나 성장 촉진제, 질병 예방용 등 수의사의 처방 없이 항생제를 사용하는 예가 많아짐에 따라 항생제 내성균도 점차 증가하고 있다. 그러므로 정확한 항생제의 판매량 파악과 내성 세균에 대한 모니터링이 매우 시급한 실정이다. 이에 본 연구에서는 돼지로부터 분리된 대장균을 대상으로 NCCLS 기준에 따라 항생제 최소억제농도를 측정하여 내성세균의 분포양상을 조사하였다. 이들 중 93.6%가 테트라사이클린에 대하여 내성을 나타내었으며, 61.1%가 클로람페니콜에 내성을 나타내었고, 64.8%가 암피실린에 내성을 나타내었다. 그리고 이들 중 33.2%가 4가지 이상의 항생제에 내성을 나타내는 다제내성 균주였다. 이에 축산농가에서 사용하고 있는 항생제에 대한 정확한 조사와 내성세균의 증가와 확산에 대한 지속적인 감시와 대책 마련이 요구된다. Overuse of antimicrobial agents in cattle farms, for treatment of infection as well as for prophylaxis and growth promotion has increased the occurrence of antimicrobial resistant bacteria. In this study, a total of 560 isolates of Eschenchia coli from pigs were isolated. Resistance of these isolates for 13 antimicrobial agents was determined by agar dilution method. Resistance rates to ampicillin, chloramphenicol, and tetracycline were 64.8%, 61.1%, and 93.6%, respectively. Mutiple drug resistance rate was 33.2%.