Publications by authors named "Sung U"

The aim of this project was to create an evidence-based learning media designed to address the behavior issues of children with Autism Spectrum Disorder (ASD) with activities of daily living. Composed of two phases, the first phase used eight school based occupational therapists identify the challenge with daily tasks and behavior management strategies for intervention. After the data was analyzed, the learning media was developed and reviewed by the therapists, content experts and 90 parents of autistic children.

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Introduction: The application of advanced technologies in paediatric rehabilitation to improve performance and enhance everyday functioning shows considerable promise. The aims of this systematic review are to investigate the effectiveness of robotic-assisted therapy for upper extremity function in children and adolescents with cerebral palsy and to extend the scope of intervention from empirical evidence.

Methods And Analysis: Multiple databases, including MEDLINE (Ovid), PubMed, CINAHL, Scopus, Web of Science, Cochrane Library and IEEE Xplore, will be comprehensively searched for relevant randomised controlled trials and non-randomised studies.

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Visualization of electrical activity in living cells represents an important challenge in context of basic neurophysiological studies. Here we report a new voltage sensitive fluorescent indicator which response could be detected by fluorescence monitoring in a single red channel. To the best of our knowledge, this is the first fluorescent protein-based voltage sensor which uses insertion-into-circular permutant topology to provide an efficient interaction between sensitive and reporter domains.

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The antidepressant-sensitive norepinephrine (NE) transporter (NET) inactivates NE released during central and peripheral neuronal activity by transport into presynaptic cells. Altered NE clearance due to dysfunction of NET has been associated with the development of mental illness and cardiovascular diseases. NET activity in vivo is influenced by stress, neuronal activity, hormones and drugs.

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Genetically encoded voltage indicators (GEVIs) have improved to the point where they are beginning to be useful for in vivo recordings. While the ultimate goal is to image neuronal activity in vivo, one must be able to image activity of a single cell to ensure successful in vivo preparations. This procedure will describe how to image membrane potential in a single cell to provide a foundation to eventually image in vivo.

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FRET (Förster Resonance Energy Transfer)-based protein voltage sensors can be useful for monitoring neuronal activity in vivo because the ratio of signals between the donor and acceptor pair reduces common sources of noise such as heart beat artifacts. We improved the performance of FRET based genetically encoded Fluorescent Protein (FP) voltage sensors by optimizing the location of donor and acceptor FPs flanking the voltage sensitive domain of the Ciona intestinalis voltage sensitive phosphatase. First, we created 39 different "Nabi1" constructs by positioning the donor FP, UKG, at 8 different locations downstream of the voltage-sensing domain and the acceptor FP, mKO, at 6 positions upstream.

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Organic voltage-sensitive dyes offer very high spatial and temporal resolution for imaging neuronal function. However these dyes suffer from the drawbacks of non-specificity of cell staining and low accessibility of the dye to some cell types. Further progress in imaging activity is expected from the development of genetically encoded fluorescent sensors of membrane potential.

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Understanding the roles of different cell types in the behaviors generated by neural circuits requires protein indicators that report neural activity with high spatio-temporal resolution. Genetically encoded fluorescent protein (FP) voltage sensors, which optically report the electrical activity in distinct cell populations, are, in principle, ideal candidates. Here we demonstrate that the FP voltage sensor ArcLight reports odor-evoked electrical activity in the in vivo mammalian olfactory bulb in single trials using both wide-field and 2-photon imaging.

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Background: Sinus irrigation has been used to treat chronic rhinosinusitis refractory to medical and surgical treatments. The aim of this study was to evaluate the effect of maxillary sinus saline irrigation on the prevention of purulent rhinorrhea, extensive granulation formation, and polyp recurrence after endoscopic sinus surgery (ESS).

Methods: This prospective, controlled study was approved by the Institutional Review Board of Gachon University Gil Medical Center.

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The norepinephrine (NE) transporter (NET) terminates noradrenergic signaling by clearing released NE at synapses. The activity of NET can be rapidly regulated by depolarization and receptor activation via Ca2+ and kinase/phosphatase-linked pathways. The SNARE protein syntaxin 1A (SYN1A) interacts with NET and influences transporter surface trafficking and catalytic activity.

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The primary mechanism for clearance of extracellular dopamine (DA) is uptake mediated by the dopamine transporter (DAT), which is governed, in part, by the number of functional DATs on the cell surface. Previous studies have shown that amphetamine (AMPH) decreases DAT cell surface expression, whereas insulin reverses this effect through the action of phosphatidylinositol 3-kinase (PI3K). Therefore, it is possible that AMPH causes DAT cell surface redistribution by inhibiting basal insulin signaling.

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Norepinephrine (NE) transporters (NETs) are high-affinity transport proteins that mediate the synaptic clearance of NE after vesicular release. NETs represent a major therapeutic target for antidepressants and are targets of multiple psychostimulants including amphetamine (AMPH) and cocaine. Recently, we demonstrated that syntaxin 1A (SYN1A) regulates NET surface expression and, through binding to the transporter's NH(2) terminus, regulates transporter catalytic function.

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The norepinephrine transporter (NET) terminates noradrenergic signals by clearing released NE at synapses. NET regulation by receptors and intracellular signaling pathways is supported by a growing list of associated proteins including syntaxin1A, protein phosphatase 2A (PP2A) catalytic subunit (PP2A-C), PICK1, and Hic-5. In the present study, we sought evidence for additional partnerships by mass spectrometry-based analysis of proteins co-immunoprecipitated with human NET (hNET) stably expressed in a mouse noradrenergic neuroblastoma cell line.

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The antidepressant-sensitive L-norepinephrine (NE) transporter (NET;SLC6A2) is a critical determinant of neurotransmitter inactivation following NE release at synapses. Although regulated trafficking of NET has been documented in transfected cells, a lack of reagents suitable for reporting native NET surface exposition has limited validation of this concept in neurons. In the current report, we document the utility of a novel antibody (43408) directed at conserved sequences in the NET second extracellular loop.

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Norepinephrine (NE) transporters (NETs) terminate noradrenergic synaptic transmission and represent a major therapeutic target for antidepressant medications. NETs and related transporters are under intrinsic regulation by receptor and kinase-linked pathways, and clarification of these pathways may suggest candidates for the development of novel therapeutic approaches. Syntaxin 1A, a presynaptic soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein, interacts with NET and modulates NET intrinsic activity.

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Presynaptic, cocaine- and antidepressant-sensitive norepinephrine (NE) transporters (NETs) dictate levels of extracellular NE after vesicular release. Recent studies suggest that G protein-coupled receptors linked to protein kinase C (PKC) down-regulate cell surface NET protein levels and diminish NE uptake capacity. We identified distinct phosphatidylinositol 3-OH kinase (PI3K)-linked pathways supporting basal and insulin-triggered NE transport in the human noradrenergic neuroblastoma, SK-N-SH.

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Programmed cell death (PCD) is a prominent feature of the development of the immune and nervous systems. In both systems, widespread PCD occurs in primitive progenitor cells during development. In this study, we demonstrated that Ewing's sarcoma (ES) cells, undifferentiated neural precursors, underwent apoptosis upon engagement of CD99 with anti-CD99 monoclonal antibody.

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We have previously reported CD4 expression in CD34+ hematopoietic progenitor cells and suggested a role of CD4 in normal hematopoiesis and its possible relationship with the pathogenesis of acquired immunodeficiency syndrome (AIDS). To investigate whether CD4 expression in bone marrow progenitor cells can explain bone marrow suppression in AIDS, monoclonal antibodies (mAbs) against human CD4 were developed by immunizing Balb/c mice with human thymocytes. Three mAbs completely blocked the binding of Leu3a antibody, a well-known anti-CD4 mAb, to thymocytes, which indicates overlap between the epitopes recognized by these and Leu3a antibodies.

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Basement membrane laminin (laminin-1) is a multidomain glycoprotein that interacts with itself, heparin and cells. The interaction with heparin/heparan sulfate proteglycans is thought to be important for the architectural formation of basement membranes and adhesion to cells. The major heparin binding site has been known to reside in the long arm globular domain (G domain).

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Laminin, a multidomain glycoprotein in basement membranes, interacts with heparin through the terminal globular domain (G domain) of its long arm. The interaction with heparin is thought to be important for modulation of basement membrane assembly and adhesion to cells. The G domain contains two different heparin binding activities: a strong one in the proximal portion and a moderate one in the distal portion of globule.

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The long arm of laminin, which binds heparin and cells, consists of three polypeptides (A, B1, and B2) joined in a coiled-coil rod attached to a terminal A chain globule (G). Previously, we found that recombinant globular domain (rG) supported heparin and myoblast binding (Yurchenco, P. D.

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A recombinant mouse cDNA fragment encoding the G domain of the basement membrane laminin A chain was inserted into the eukaryotic baculovirus expression vector pVL1392 modified to produce fusion proteins carrying the rat fibronectin signal. G domain, expressed and secreted as a soluble glycoprotein (rG), was purified to near homogeneity without denaturing conditions. By electron microscopy rG possessed the same globular morphology as found in laminin.

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