Childhood Primary Angiitis of the Central Nervous System Presenting as Isolated Middle Cerebral Artery Dissection

Matthew Chung,Yong Woo Shin,권형민 대한신경초음파학회 2022 대한신경초음파학회지 (JNN) Vol.14 No.1

Isolated middle cerebral artery dissection and primary angiitis of the central nervous system are two rare but serious causes of ischemic stroke in children. We report a case of a patient who presented with headache, left-sided hemiparesis, and left hemi-hypoesthesia with acute cerebral infarction in the right middle cerebral artery territory. Brain magnetic resonance imaging showed isolated right middle cerebral artery dissection with arterial wall contrast enhancement extending beyond the length of the dissection and diffuse narrowing with stenosis in the right posterior cerebral artery suggesting angiitis. After exclusion of other diagnoses the patient was treated with corticosteroids and dual antiplatelet therapy. Follow up magnetic resonance imaging performed 4 months later showed partially improved contrast enhancement in the right middle cerebral artery and persistent narrowing and focal stenosis of the right posterior cerebral artery. Although rare, primary angiitis of the central nervous system should be considered in the differential diagnosis of acute stroke in children. High-resolution vessel wall imaging magnetic resonance studies can provide important information in determining the etiology of stroke.

Topical Application of MS-275 Decreases the Imiquimod-Induced Hyperproliferative Epidermis and Interleukin-23 Expression in the Upper Dermis of BALB/c Mouse

( Matthew H. Friedland ),( Emily A. Mann ),( Daniela N. Frankel ),( Hye Jin Chung ),( Jean S. Mcgee ) 대한피부과학회 2021 Annals of Dermatology Vol.33 No.2

DEVELOPMENT OF CHEMICAL SENSORS USING MICROFABRICATION TECHNIQUES

Liu, Chung-Chiun,Wu, Qinghai,Makovos, Edward,Stuczynski, Matthew,Savinell, Robert 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

Feeding State, Insulin and NPR-1 Modulate Chemoreceptor Gene Expression via Integration of Sensory and Circuit Inputs

Gruner, Matthew,Nelson, Dru,Winbush, Ari,Hintz, Rebecca,Ryu, Leesun,Chung, Samuel H.,Kim, Kyuhyung,Gabel, Chrisopher V.,van der Linden, Alexander M. Public Library of Science 2014 PLoS genetics Vol.10 No.10

<P>Feeding state and food availability can dramatically alter an animals' sensory response to chemicals in its environment. Dynamic changes in the expression of chemoreceptor genes may underlie some of these food and state-dependent changes in chemosensory behavior, but the mechanisms underlying these expression changes are unknown. Here, we identified a KIN-29 (SIK)-dependent chemoreceptor, <I>srh-234</I>, in <I>C. elegans</I> whose expression in the ADL sensory neuron type is regulated by integration of sensory and internal feeding state signals. We show that in addition to KIN-29, signaling is mediated by the DAF-2 insulin-like receptor, OCR-2 TRPV channel, and NPR-1 neuropeptide receptor. Cell-specific rescue experiments suggest that DAF-2 and OCR-2 act in ADL, while NPR-1 acts in the RMG interneurons. NPR-1-mediated regulation of <I>srh-234</I> is dependent on gap-junctions, implying that circuit inputs regulate the expression of chemoreceptor genes in sensory neurons. Using physical and genetic manipulation of ADL neurons, we show that sensory inputs from food presence and ADL neural output regulate <I>srh-234</I> expression. While KIN-29 and DAF-2 act primarily via the MEF-2 (MEF2) and DAF-16 (FOXO) transcription factors to regulate <I>srh-234</I> expression in ADL neurons, OCR-2 and NPR-1 likely act via a calcium-dependent but MEF-2- and DAF-16-independent pathway. Together, our results suggest that sensory- and circuit-mediated regulation of chemoreceptor genes via multiple pathways may allow animals to precisely regulate and fine-tune their chemosensory responses as a function of internal and external conditions.</P><P><B>Author Summary</B></P><P>Animals dramatically modify their chemosensory behaviors to attractive and noxious chemical stimuli when starved. This could allow them to alter and optimize their food-search strategies to increase their survival and reproduction. Changes in the gene expression of chemoreceptors specialized in detecting environmental stimuli is observed in fish, insects and nematodes, and may be a general mechanism underlying the changes in chemosensory behaviors observed in starved animals. To elucidate this mechanism, we have developed an <I>in vivo</I> reporter assay in <I>C. elegans</I> for monitoring the expression of a candidate chemoreceptor gene in a single sensory neuron type, called ADL, as a function of feeding state. Using this reporter assay, we show that sensory inputs into ADL and neural outputs from ADL, as well as inputs from the RMG interneuron, which is electrically connected to ADL, are required to fine-tune expression of chemoreceptor genes in ADL. Sensory and circuit-mediated regulation of chemoreceptor gene expression is dependent on multiple pathways, including the neuropeptide receptor, NPR-1, and the DAF-2 insulin-like receptor. Our results reveal mechanisms underlying chemoreceptor gene expression, and provide insight into how expression changes in chemoreceptor genes may contribute to changes in chemosensory behavior as a function of feeding state.</P>

Phylogenetic analysis of the swine leukocyte antigen - 2 gene for Korean native pigs

Hoyoung Chung,Matthew McClure,Jaeyoung Kim 한국유전학회 2011 Genes & Genomics Vol.33 No.4

The objective of this study was to investigate genetic relationships of the SLA-2 gene, to characterize SLA-2 alleles, and to provide basic genetic information of Korean pigs. The swine leukocyte antigen - 2 (SLA-2) gene in the MHC classical region was cloned with spleen tissues from Korean native pigs selected from the main land (KNP) and Jeju Island (KJP). Primer sequences based on swine cDNA (GenBank accession numbers AF464049 and AF464005) were used to amplify the entire SLA-2 gene, and the amplification product including both 3’ and 5’ UTRs was sized 1,520 bp. A BAC clone was selected from miniature pigs and sequenced for the genomic region of the SLA-2 gene showing that 4,585 bp in total length consisted of exons (1,087 bp) and introns (3,498 bp). A sequence analysis confirmed 58 SNPs in coding regions, which revealed higher numbers of SNPs in KNP than other pig breeds, implicating more genetic variability in Korean pigs. Approximately 82% of the SLA-2 SNPs were located in the highly polymorphic exons 2 and 3. Newly identified sequences of the SLA-2 gene for KNP and KJP were submitted into the IPD-MHC database with new nomenclatures (SLA-2*1501,SLA-2*1601, and SLA-2*w08hy01 allele), while the representative sequences of KNP and KJP were submitted into GenBank with accession numbers (DQ992495, DQ992496,and DQ992501), respectively. The identified KNP allele (SLA-2*1501) clustered with previously defined alleles for Korean pigs (SLA-2*kn02 and SLA-2*jh01), but SLA-2*1601(KNP) and SLA-2*w08hy01 (KJP) alleles showed no significant genetic relationships with any other allele. A sequence comparison revealed that KNP has departed from KJP both genetically and phenotypically. The results of SLA-2 SNP in KNP and KJP reported here will serve as the SLA-2 reference for Korean pigs.

Cell Docking in Double Grooves in a Microfluidic Channel

Khabiry, Masoud,Chung, Bong Geun,Hancock, Matthew J.,Soundararajan, Harish Chandra,Du, Yanan,Cropek, Donald,Lee, Won Gu,Khademhosseini, Ali WILEY-VCH Verlag 2009 Small Vol.5 No.10

<P>Microstructures that generate shear-protected regions in microchannels can rapidly immobilize cells for cell-based biosensing and drug screening. Here, a two-step fabrication method is used to generate double microgrooves with various depth ratios to achieve controlled double-level cell patterning while still providing shear protection. Six microgroove geometries are fabricated with different groove widths and depth ratios. Two modes of cell docking are observed: cells docked upstream in sufficiently deep and narrow grooves, and downstream in shallow, wide grooves. Computational flow simulations link the groove geometry and bottom shear stress to the experimental cell docking patterns. Analysis of the experimental cell retention in the double grooves demonstrates its linear dependence on inlet flow speed, with slope inversely proportional to the sheltering provided by the groove geometry. Thus, double-grooved microstructures in microfluidic channels provide shear-protected regions for cell docking and immobilization and appear promising for cell-based biosensing and drug discovery.</P> <B>Graphic Abstract</B> <P>A microfluidic device containing a double-grooved substrate for cell docking and positioning is presented. Numerical simulations of microcirculations within double grooves (see image) elucidate the dependence of the flow pattern on groove geometry. Cell docking and retention are measured experimentally for double grooves of two aspect ratios and three depth ratios, and correlate directly to the microcirculation pattern. <img src='wiley_img/16136810-2009-5-10-SMLL200801644-content.gif' alt='wiley_img/16136810-2009-5-10-SMLL200801644-content'> </P>

Collaborative Swarm for Multi-Task Pairing in Unknown Environment

Jae H. Chung,Jun-Ho Jang,Tae-Young Kim,Matthew Kim 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

Remotely operating teams of autonomous mobile robots for multi-task allocations in an unknown environment is an important and challenging task in many real world applications. However, a few of existing teleoperation methods have been aimed at finishing multiple tasks simultaneously when the environment that the robots are navigating is unknown. In real life, in order to achieve this, a teleoperated team of mobile robots can be split into several collaborative sub-teams according to their characteristics about different tasks. Each sub-team is formed by pairing team robots to a specific task to make sure of an enough capability of automatically sensing environments and accomplishing the specific task. Moreover, the robot-task pairing strategy based on the capability list of robots in a weighted attack guidance table (WAGT) is developed from the proven auction algorithm for multi-robot multi-task cases, which optimizes effects-based allocations based on a heuristic algorithm. In this paper, a control method to teleoperate teams or sub-teams of robots involving the robot-task pairing strategy is proposed to deal with different tasks simultaneously in an unknown environment. Simulation studies illustrate the efficacy of a teleoperator with the proposed control method for multi-task scenarios in an unknown environment.

Telomerase activity is required for bleomycin-induced pulmonary fibrosis in mice.

Liu, Tianju,Chung, Myoung Ja,Ullenbruch, Matthew,Yu, Hongfeng,Jin, Hong,Hu, Biao,Choi, Yoon Young,Ishikawa, Fuyuki,Phan, Sem H American Society for Clinical Investigation 2007 The Journal of clinical investigation Vol.117 No.12

<P>In addition to its well-known expression in the germline and in cells of certain cancers, telomerase activity is induced in lung fibrosis, although its role in this process is unknown. To identify the pathogenetic importance of telomerase in lung fibrosis, we examined the effects of telomerase reverse transcriptase (TERT) deficiency in a murine model of pulmonary injury. TERT-deficient mice showed significantly reduced lung fibrosis following bleomycin (BLM) insult. This was accompanied by a significant reduction in expression of lung alpha-SMA, a marker of myofibroblast differentiation. Furthermore, lung fibroblasts isolated from BLM-treated TERT-deficient mice showed significantly decreased proliferation and increased apoptosis rates compared with cells isolated from control mice. Transplantation of WT BM into TERT-deficient mice restored BLM-induced lung telomerase activity and fibrosis to WT levels. Conversely, transplantation of BM from TERT-deficient mice into WT recipients resulted in reduced telomerase activity and fibrosis. These findings suggest that induction of telomerase in injured lungs may be caused by BM-derived cells, which appear to play an important role in pulmonary fibrosis. Moreover, TERT induction is associated with increased survival of lung fibroblasts, which favors the development of fibrosis instead of injury resolution.</P>

Lymphomatoid Granulomatosis: CT and FDG-PET Findings

Jonathan H. Chung,Carol C. Wu,Matthew D. Gilman,Edwin L. Palmer,Robert P. Hasserjian,Jo-Anne O. Shepard 대한영상의학회 2011 Korean Journal of Radiology Vol.12 No.6

Objective: Lymphomatoid granulomatosis (LG) is a rare, aggressive extranodal Epstein-Barr virus (EBV)-positive B-cell lymphoproliferative disease. The purpose of our study was to analyze the CT and fluorodeoxyglucose positron emission tomography (FDG-PET) findings of pulmonary LG. Materials and Methods: Between 2000 and 2009, four patients with pathologically proven pulmonary LG and chest CT were identified. Two of these patients also had FDG-PET. Imaging features of LG on CT and PET were reviewed. Results: Pulmonary nodules or masses with peribronchovascular, subpleural, and lower lung zonal preponderance were present in all patients. Central low attenuation (4 of 4 patients), ground-glass halo (3 of 4 patients), and peripheral enhancement (4 of 4 patients) were observed in these nodules and masses. An air-bronchogram and cavitation were seen in three of four patients. FDG-PET scans demonstrated avid FDG uptake in the pulmonary nodules and masses. Conclusion: Pulmonary LG presents with nodules and masses with a lymphatic distribution, as would be expected for a lymphoproliferative disease. However, central low attenuation, ground-glass halo and peripheral enhancement of the nodules/masses are likely related to the angioinvasive nature of this disease. Peripheral enhancement and ground-glass halo, in particular, are valuable characteristic not previously reported that can help radiologists suggest the diagnosis of pulmonary LG. Objective: Lymphomatoid granulomatosis (LG) is a rare, aggressive extranodal Epstein-Barr virus (EBV)-positive B-cell lymphoproliferative disease. The purpose of our study was to analyze the CT and fluorodeoxyglucose positron emission tomography (FDG-PET) findings of pulmonary LG. Materials and Methods: Between 2000 and 2009, four patients with pathologically proven pulmonary LG and chest CT were identified. Two of these patients also had FDG-PET. Imaging features of LG on CT and PET were reviewed. Results: Pulmonary nodules or masses with peribronchovascular, subpleural, and lower lung zonal preponderance were present in all patients. Central low attenuation (4 of 4 patients), ground-glass halo (3 of 4 patients), and peripheral enhancement (4 of 4 patients) were observed in these nodules and masses. An air-bronchogram and cavitation were seen in three of four patients. FDG-PET scans demonstrated avid FDG uptake in the pulmonary nodules and masses. Conclusion: Pulmonary LG presents with nodules and masses with a lymphatic distribution, as would be expected for a lymphoproliferative disease. However, central low attenuation, ground-glass halo and peripheral enhancement of the nodules/masses are likely related to the angioinvasive nature of this disease. Peripheral enhancement and ground-glass halo, in particular, are valuable characteristic not previously reported that can help radiologists suggest the diagnosis of pulmonary LG.

Effect of Glycyrrhizin on Rainbow Trout Oncorhynchus mykiss Leukocyte Responses

Seon Il Jang,Matthews J. Marsden,Christopher J. Secombes,Min Sun Choi,Young Gill Kim,Kang Ju Kim,Hun-Tack Chung 大韓微生物學會 1998 大韓微生物學會誌 Vol.33 No.3