Muscle-specific receptor tyrosine kinase (MuSK) myasthenia gravis associated with castleman disease

Oh, Jeeyoung,Yang, Woo Ick,Cho, Jeong Hoon,Sunwoo, Il Nam The Korean Society of Clinical Neurophysiology 2017 Annals of Clinical Neurophysiology Vol.19 No.1

Muscle specific tyrosine kinase (MuSK) myasthenia gravis (MG) is a rare subtype of MG, which is immunologically distinct and differential therapeutic response. Though MG is often associated with other autoimmune disorders or malignancy, concurrence of other disease and MuSK MG has been infrequently reported. We present a patient of MuSK MG associated with multicentric Castelman disease.

Clinical spectrum and diagnosis of diabetic neuropathies

Jeeyoung Oh 대한내과학회 2020 The Korean Journal of Internal Medicine Vol.35 No.5

Neuropathy is the most prevalent microvascular complication of diabetes mellitus; it encompasses distal symmetric polyneuropathy, autonomic neuropathy, radiculoplexus neuropathy, mononeuropathy, and treatment-induced neuropathy. The prevalence rate of diabetic neuropathy in Korea was reported to be approximately 43%, which is similar to rates in other countries. However, the precise pathogenic mechanism underlying diabetic neuropathy is still obscure, and many clinical trials have failed to develop methods to prevent or reduce the progression of diabetic neuropathy. Nevertheless, early diagnosis and proper management of diabetic neuropathy are essential to alleviate disabling symptoms and to improve the quality of life of patients. This review discusses clinical manifestations and classification of diabetic neuropathies, bedside neurological examination, and electrophysiological tests.

Clinical Usefulness of a Cell-based Assay for Detecting Myelin Oligodendrocyte Glycoprotein Antibodies in Central Nervous System Inflammatory Disorders

Seok Jin Myoung,Waters Patrick,Jeon Mi Young,Lee Hye Lim,Baek Seol-Hee,Park Jin-Sung,Kang Sa-Yoon,Kwon Ohyun,Oh Jeeyoung,Oh Jeeyoung,Park Kyung-Ah,Oh Sei Yeul,Kim Byoung Joon,Min Ju-Hong 대한진단검사의학회 2024 Annals of Laboratory Medicine Vol.44 No.1

Background: The clinical implications of myelin oligodendrocyte glycoprotein autoantibodies (MOG-Abs) are increasing. Establishing MOG-Ab assays is essential for effectively treating patients with MOG-Abs. We established an in-house cell-based assay (CBA) to detect MOG-Abs to identify correlations with patients’ clinical characteristics. Methods: We established the CBA using HEK 293 cells transiently overexpressing full-length human MOG, tested it against 166 samples from a multicenter registry of central nervous system (CNS) inflammatory disorders, and compared the results with those of the Oxford MOG-Ab-based CBA and a commercial MOG-Ab CBA kit. We recruited additional patients with MOG-Abs and compared the clinical characteristics of MOG-Ab-associated disease (MOGAD) with those of neuromyelitis optica spectrum disorder (NMOSD). Results: Of 166 samples tested, 10 tested positive for MOG-Abs, with optic neuritis (ON) being the most common manifestation (4/15, 26.7%). The in-house and Oxford MOG-Ab CBAs agreed for 164/166 (98.8%) samples (κ=0.883, P<0.001); two patients (2/166, 1.2%) were only positive in our in-house CBA, and the CBA scores of the two laboratories correlated well (r=0.663, P<0.001). The commercial MOG-Ab CBA kit showed one false-negative and three false-positive results. The clinical presentation at disease onset differed between MOGAD and NMOSD; ON was the most frequent manifestation in MOGAD, and transverse myelitis was most frequent in NMOSD. Conclusions: The in-house CBA for MOG-Abs demonstrated reliable results and can potentially be used to evaluate CNS inflammatory disorders. A comprehensive, long-term study with a large patient population would clarify the clinical significance of MOG-Abs.

Fabrication of Invisible Ag Nanowire Electrode Patterns Based on Laser-Induced Rayleigh Instability

Oh, Harim,Lee, Jeeyoung,Kim, Jin-Hoon,Park, Jin-Woo,Lee, Myeongkyu American Chemical Society 2016 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.120 No.36

<P>We here present a laser-patterning method that may solve the-visibility problem associated with silver nanowire (AgNW) transparent electrodes. In conventional methods, AgNW electrodes are patterned on a transparent substrate by either selective removal or deposition of the material. Therefore, the fabricated pattern becomes visible due to the difference in transmittance/reflectance between the regions with and without AgNWs. Our approach is to disconnect the AgNW networks in selective areas by a laser and thus make the irradiated areas electrically insulating. This method is fundamentally based on Rayleigh instability. Given that the laser-cut nanowires remain on the substrate, the electrode pattern fabricated by the method can be invisible. The feasibility of the presented approach is demonstrated by fabricating organic light-emitting diodes using patterned AgNW electrodes and then characterizing their performance capabilities.</P>

Laser-Induced Dewetting of Metal Thin Films for Template-Free Plasmonic Color Printing

Oh, Harim,Lee, Jeeyoung,Seo, Minseok,Baek, In Uk,Byun, Ji Young,Lee, Myeongkyu American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.44

<P>Plasmonic color laser printing has several advantages over pigment-based technology, including the absence of ink and toner and the production of nonfading colors. However, the current printing method requires a template that should be prepared via nanofabrication processes, making it impractical for large-area color images. In this study, we show that laser-induced dewetting of metal thin films by a nanosecond pulsed laser can be effectively utilized for plasmonic color printing. Ag, Au, and their complex films deposited on a glass substrate were dewetted into different surface structures such as droplets, rods, and ripples, depending on the incident laser energy. The resulting morphological evolutions could be explained by Rayleigh and capillary instabilities. For a bimetallic film comprising Ag nanowires coated on a Au layer, a few different plasmonic colors were generated from a single sample simply by changing the laser fluence. This provides a possible method for implementing plasmonic color laser printing without using a prepatterned template.</P> [FIG OMISSION]</BR>

Superior Cluneal Nerve Entrapment as Uncommon Cause of Buttock Pain

Jeeyoung Jun,Jinyoung Oh,Dahee Park 대한통증연구학회 2021 International Journal of Pain Vol.12 No.1

The superior cluneal nerve is a pure sensory cutaneous nerve and dominates sensation in the low back and buttock area. Entrapment of superior cluneal nerve around the iliac crest, superior cluneal neuropathy, is one of the etiology of low back pain or buttock pain, but diagnosis and treatment are still challenging. Here, we report a case that the buttock pain from cluneal nerve entrapment was diagnosed and treated by percutaneous interventions. Our patient, in this case, complained of chronic buttock pain that lasted for 6 months, and there was no response to the epidural block, medial branch block, and sacroiliac joint block, but the pain was relieved through the superior cluneal nerve block, and it was diagnosed as superior cluneal nerve entrapment neuropathy. The pain could be treated through nerve block and pulsed radiofrequency therapy. Buttock pain can be induced in many diseases, and accurate diagnosis cannot be made only by imaging studies and physical examination. Two or more diseases can simultaneously cause similar symptoms. Although superior cluneal nerve entrapment causes severe buttock pain, among several causes, it is difficult to diagnose superior cluneal nerve entrapment as the cause first. It is suggested that superior cluneal entrapment neuropathy could be considered as one of the causes in patients with buttock pain.

Transformation of silver nanowires into nanoparticles by Rayleigh instability: Comparison between laser irradiation and heat treatment

Oh, Harim,Lee, Jeeyoung,Lee, Myeongkyu Elsevier 2018 APPLIED SURFACE SCIENCE - Vol.427 No.2

<P><B>Abstract</B></P> <P>We comparatively study the morphological evolutions of silver nanowires under nanosecond-pulsed laser irradiation and thermal treatment in ambient air. While single-crystalline, pure Ag nanospheres could be produced by laser-driven Rayleigh instability, the particles produced by heat treatment were subject to oxidation and exhibited polyhedron shapes. The different results are attributed to the significantly different time scales of the two processes. In this article, we also show that bimetallic Ag-Au nanospheres can be synthesized by irradiating Ag nanowires coated with a thin Au film using a pulsed laser beam. This may provide a facile route to tune the plasmonic behavior of metal nanoparticles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ag nanowires can be transformed into single-crystalline nanospheres by laser-driven Rayleigh instability. </LI> <LI> Ag-Au alloy nanospheres are also produced by irradiating Ag nanowires coated with a thin Au film. </LI> <LI> The process may be effectively utilized for the synthesis and plasmonic tuning of bimetallic nanoparticles. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Fabrication of Ag-Au bimetallic nanoparticles by laser-induced dewetting of bilayer films

Oh, Yoonseok,Lee, Jeeyoung,Lee, Myeongkyu Elsevier 2018 APPLIED SURFACE SCIENCE - Vol.434 No.-

<P><B>Abstract</B></P> <P>We here show that Ag-Au bimetallic nanoparticles (NPs) can be produced by dewetting an Ag/Au bilayer film coated on glass using a nanosecond-pulsed laser beam. Elemental analysis revealed that the obtained bimetallic NPs are Ag-Au alloys, with two elements well mixed over the whole volume of the particle. The composition of the produced particles was controllable by changing the relative thickness of each layer. The localized surface plasmon resonance (LSPR) peak was red-shifted with an increasing Au content and the LSPR wavelength could be tuned from 415 to 525 nm by varying the alloy composition. A film area of several square centimeters could be transformed into Ag-Au NPs by a single laser pulse of 6 ns duration. This study provides a facile and scalable route to prepare bimetallic NPs for plasmonic and other applications.</P> <P><B>Highlights</B></P> <P>Ag-Au bimetallic nanoparticles are produced by laser-induced dewetting of bilayer films.</P> <P>A film area of several square centimeters can be dewetted into nanoparticles by a single laser pulse.</P> <P>The process may be effectively utilized for the synthesis and plasmonic tuning of bimetallic nanoparticles.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Validation of Social Responsiveness Scale for Korean Preschool Children With Autism

Jeeyoung Chun,Guiyoung Bong,Jae Hyun Han,Miae Oh,Hee Jeong Yoo 대한신경정신의학회 2021 PSYCHIATRY INVESTIGATION Vol.18 No.9

Objective This cross-cultural study aims to examine the psychometric properties of the Social Responsiveness Scale (SRS) and to determine the best-estimate-cut-off scores for the diagnosis of autism spectrum disorder (ASD) in Korean preschool children.Methods A total of 563 children was recruited from multiple sources, including Seoul National University Bundang Hospital. Participants were assessed by a multidisciplinary research team using multiple diagnostic tools based on DSM-5 diagnostic criteria. Discriminative validity was tested by comparing the difference in SRS scores between ASD and non-ASD groups. Convergent validity was tested by examining correlations between SRS scores with other diagnostic instruments. A receiver operation characteristic curve analysis was conducted to test the sensitivity and specificity of SRS and to determine the best-estimate-cut-off scores for screening ASD in Korean preschool children.Results There were significant differences in the total SRS scores between the ASD (n=242) and non-ASD group (n=321) (p<0.01, 95% confidence interval [CI]: 14.08–17.24). The differences were significant even after adjusting for age. SRS scores were significantly correlated with other prescreening diagnostic tools for ASD. The best-estimate cut-off score to screen ASD was 55 (area under curve=0.88, sensitivity 78.1%, specificity 86.6%).Conclusion The SRS is a valid and reliable instrument to screen and aid in the diagnosis of ASD in Korean preschool children. The adjusted cut-off scores, notably lower than in the original U.S. version, may yield a more accurate diagnosis by reflecting transcultural differences.

말초신경질환의 진단검사로서 피부 생검의 유용성

오지영,Oh, Jeeyoung 대한임상신경생리학회 2007 Annals of Clinical Neurophysiology Vol.9 No.2

Analysis of intraepidermal nerve fibers using skin biopsy is a recently developed technique, providing diagnostic information on small fiber neuropathies. The specimens are obtained by 3 mm punch biopsy, which is safe and minimally invasive. Immunohistochemical staining by Protein gene product (PGP) 9.5 demonstrate not only intraepidermal nerve fibers but dermal structures, such as sweat gland and erector papillae. Up to now, many studies agree that intraepidermal nerve fiber density is dramatically reduced in various sensory neuropathies. The utility of density measure was confirmed with high sensitivity in the diagnosis of sensory neuropathy, comparable to sural nerve biopsy or quantitative sensory testing. Besides quantitative methods, morphological changes like axonal swelling and fragmentation can be used as predegenerative markers. This article reviews the technique of skin biopsy and clinical and experimental usefulness of skin biopsy in diagnosing and monitoring peripheral neuropathies.