1.Expression of NMDA Receptor Subunit mRNAs in the Developing Circadian Pacemaker of the Rat.
Hwan Tae PARK ; Seung Gu KANG ; Eun Kyoung KANG ; Ki Won BAE
Korean Journal of Anatomy 1998;31(4):595-601
Hypothalamic suprachiasmatic nucleus (SCN) is a circadian pacemaker which controls diurnal behavioral and hormonal rhythms in mammals. The SCN receives environmental light signals through the retinohypothalamic tract, and glutamate is the major excitatory neurotransmitter in the retinohypothalamic tract. In the present study, we investigated the developmental expression of the mRNAs for N-methyl-D-aspartate type glutamate receptor (NR)1, NR2A, NR2B and NR2C subunits in the rat SCN using in situ hybridization with specific riboprobes. At postnatal day 2 (P2), P8, Pl5 and P45, the high level of NRI transcripts was observed in both ventrolateral and dorsomedial subdivisions of the SCN, and the distinct expression of NR2C mRNA was principally found in the dorsomedial SCN. The weak NR2B mRNA expression was clearly found in both subdivisions of the SCN at P2 and P8, whereas specific NR2B hybridization signals were not found at Pl5 and P45. There was no specific hybridization signal of NR2A in the SCN throughout the postnatal life. These findings implicate that NR may play an important role in the neonatal SCN. In addition, this study suggests that NR1, NR2B and NR2C might be the major NR subunits in the developing SCN, whereas NRI and NR2C could be the subunit components of NR in the adult SCN.
Adult
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Animals
;
Glutamic Acid
;
Humans
;
In Situ Hybridization
;
Mammals
;
N-Methylaspartate*
;
Neurotransmitter Agents
;
Rats*
;
Receptors, Glutamate
;
RNA, Messenger*
;
Suprachiasmatic Nucleus
2.Association of Ubiquitin-Positive Neuritic Threads in the CA 2-3 Region of the Hippocampus with Cortical Lewy Bodies.
Ki Hwa YANG ; Ki Seung YANG ; Choong Gu KANG ; Joo Ho SUNG
Korean Journal of Pathology 1995;29(5):660-668
Ubiquitin-positive neuritic threads (UNTS) in the hippocampal CA 2-3 region are reported to occur exclusively in association with so-called diffuse Lewy body disease (DLBD). hi order to assess the association between the occurrence of Lewy bodies (LBs) and that of the UNTs, an immunohistochemical study on the hippocampus including the parahippocampal gyrus with antiubiquitin antibody (Chemicon Co., California, U.S.A.) was perfon-ned in four groups of patient's brains. All brains were selected from the large pool of brains referred to the Neuropadiology Laboratory of the University of Minnesota for studies of Alzheimer's disease. Group 1 consisted of 34 cases (20 male and 14 female) with LBs widespread in the frontal and temporal cortex and the brain stem nuclei (basal nucleus, substantia nigra, locus ceruleus and dorsal vagal nucleus) associated with varying degrees of degeneration of the substantia nigra; 21 (11 male and 10 female) combined with and 13 (9 male and 4 female) without Alzheimer's disease (AD) pathology. Group 2 included 12 cases (9 male and 3 female) in which LBs were observed only in the brain stem nuclei; 7 with and 4 without AD pathology. Group 3 consisted of 30 cases (9 male and 21 female) without LBs but with AD pathology and degeneration of the substantia nigra. Group 4 included 23 cases (11 male and 12 female) with neither LBs nor AD pathology but with degeneration of the substantia nigra. Ages of the patients varied among the groups. In the 46 cases in the first two groups with LBs. The mean age in the 28 cases with AD pathology was 77.3+/-8.9 and in the 18 cases without AD pathology it was 71.6+/-8.8 (P<0.05). In the 53 cases in groups 3 and 4 without LBs, which served as the controls, the mean ages were 80.8+/-7.7 and 74.0+/-9.7 respectively. UNTs were encountered in all (100%) of 34 cases of group I with widespread LBs which met the histological criteria of DLBD regardless of combined AD pathology. In 12 cases of group 2 with LBs confined to the brain stem, UNTs occurred in 3 (25%), 1 with and 2 without AD pathology. hi the group 3 cases with only AD pathology, UNTs occurred in 4 (13%) of 30 cases, while no UNTs were encountered in the 23 cases of group 4 without AD pathology or LBs. In conclusion, UNTs in the hippocampal CA 2-3 region occur invariably but not exclusively in association with widespread LBs, frequently when LBs are confined to the brain stem, and infrequently with AD pathology. It seems, therefore, that the UNTs are closely related to LBs and increase in ftequency as LBs spread beyond the brain stem with time, but the pathogenesis of the UNTs is little understood.
Female
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Male
;
Humans
3.The Use of Hydroxychloroquine in Patients with Pemphigus Erythematosus.
Korean Journal of Dermatology 1996;34(6):980-983
Pemphigus erythematosus (PE) is a superficial type of pemphigus, which can be aggravated by sunlight (espicially UV light). Because of the known side effects of corticosteroids, we evaluated the efficacy of hydroxychloroquine as a corticosteroid-sparing agent and/or the effect of a single-drug regimen in two patients with PE with photosensitivity. We obtained a good therapeutic response with hydroxychloroquine in these two patients with PE. This drug could be used in selected patients with pemphigus who are prednisolone/ immunosuppressive-resistant or who have certain degrees of photosensitivity.
Adrenal Cortex Hormones
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Humans
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Hydroxychloroquine*
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Pemphigus*
;
Sunlight
4.Transepidermal Elimination of Nevus Cells in Acral Lentiginous Nevus.
Hee Jeon YU ; Hong Yoon YANG ; Jae Yong BAHN ; Yun Suck KIM ; Seung Gu KANG
Korean Journal of Dermatology 1999;37(4):544-546
Pigmented lesions of palmar and plantar skin may cause diagnostic problems, because some features of benign lesions in these sites may raise the suspicion of melanoma if considered alone. Transepidermal elimlnation is a mechanism by which a substance is eliminated through the epidermis, and it is apt to be confused with a feature of melanoma that tumor cells are located at all layers of the epidermis. We report a case of transepidermal elimination of nevus cells in acral letiginous nevus which needs a differential dignosis of melanoma.
Epidermis
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Melanoma
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Nevus*
;
Skin
5.Evaluation of left artial appendage function by transesophageal echocardiography.
Hyun Chul SHIN ; Seung Ho KANG ; Dong Gu SHIN ; Young Jo KIM ; Bong Sup SHIM ; Hyun Woo LEE
Journal of the Korean Society of Echocardiography 1993;1(1):109-118
No abstract available.
Echocardiography, Transesophageal*
6.Event-related Potential Patterns Reflect Reversed Hemispheric Activity during Visual Attention Processing in Children with Dyslexia: A Preliminary Study.
Joong Gu KANG ; Seung Hwan LEE ; Eun Jin PARK ; Hyun Sung LEEM
Clinical Psychopharmacology and Neuroscience 2016;14(1):33-42
OBJECTIVE: Individuals with dyslexia experience reading difficulties, whereas their other cognitive abilities seem normal. The purpose of this study was to investigate the event-related potential (ERP) patterns of children with dyslexia during a target-detection task. METHODS: Seventeen children with dyslexia and 18 children without this disorder participated in this study. We evaluated their writing and reading ability, symptoms of attention-deficit/hyperactivity disorder, and intelligence quotient. ERPs were recorded while participants performed a target-detection task, and the peak amplitude and latency of P100 and P300 were analyzed. The lateral asymmetry index (LAI) was calculated for each ERP component. RESULTS: The dyslexic group exhibited longer reaction times and larger P100 amplitudes than the non-dyslexic group in the right hemisphere. The P100 latency was also significantly delayed in the right hemisphere of those in the dyslexic group compared with those in the non-dyslexic group. The P300 amplitude was larger in the right hemisphere compared with left hemisphere in the dyslexic group, whereas no interhemispheric differences were observed with respect to the P300 latency. The LAI for P100 showed a significant right hemispheric dominance, whereas the LAI for P100 was significantly correlated with the accuracy of target detection in children with dyslexia. CONCLUSION: Our results suggest that right hemispheric dominance acts as an ancillary system that compensates for poor reading in children with dyslexia.
Child*
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Dyslexia*
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Evoked Potentials*
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Humans
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Intelligence
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Reaction Time
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Reading
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Writing
7.The Effect of Simvastatin on the Expression of Catalase in Human Retinal Pigment Epithelial Cells.
Min Gu KANG ; So Young LEE ; Hee Seung CHIN
Journal of the Korean Ophthalmological Society 2014;55(10):1535-1542
PURPOSE: To evaluate the effects of simvastatin on the catalase expression in human retinal pigment epithelium. METHODS: Retinal pigment epithelial (RPE) cells were incubated for 6 hours and 24 hours with various concentrations of simvastatin. In addition, RPE cells were incubated with 200 microM of H2O2 and various concentrations of simvastatin. After incubation, real-time polymerase chain reaction (PCR) was performed to examine the catalase messenger ribonucleic acid (mRNA) expression and a catalase assay was performed to examine the catalase activity in RPE. Intracellular reactive oxygen species (ROS) was measured using a fluorescence activated cell sorter (FACS). RESULTS: Simvastatin increased the amount of catalase mRNA and catalase activity at 10 microM in RPE cells. Under oxidative stress (200 microM of H2O2), 2.5 microM of simvastatin increased the catalase mRNA expression and 5 microM of simvastatin increased catalase activity in RPE cells. In addition, simvastatin reduced free radical formation but this effect was diminished in the presence of an irreversible catalase inhibitor, 3-amino-1,2,4-triazole (3-AT). CONCLUSIONS: Simvastatin exhibits anti-oxidative effects by inducing the catalase expression in human RPE cells. This anti-oxidative effect may be beneficial for preventing age-related macular degeneration induced by oxidative stress.
Amitrole
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Catalase*
;
Epithelial Cells*
;
Fluorescence
;
Humans
;
Macular Degeneration
;
Oxidative Stress
;
Reactive Oxygen Species
;
Real-Time Polymerase Chain Reaction
;
Retinal Pigment Epithelium
;
Retinaldehyde*
;
RNA
;
RNA, Messenger
;
Simvastatin*
8.Effects of Clozapine, Haloperidol, and Fluoxetine on the Reversal of Cocaine-Induced Locomotor Sensitization.
Psychiatry Investigation 2014;11(4):454-458
OBJECTIVE: Repeated treatment with psychostimulants induces sensitization of the dopaminergic system in the brain. Dopaminergic sensitization has been proposed as a mechanism of psychosis. Although antipsychotics block the expression of sensitized behavior, they are ineffective for reversing the sensitized state. We investigated the effect of clozapine, haloperidol, and fluoxetine on the reversal of cocaine-induced behavioral sensitization. METHODS: Male ICR mice were sensitized to cocaine with repeated treatment. Animals were then split into four groups, and each group was treated with vehicle or one of the above drugs for 5 days. After a 3-day drug washout, locomotor activity was assessed before and after a cocaine challenge. RESULTS: Clozapine reversed the sensitized state, whereas haloperidol did not. Fluoxetine seemed to reverse the sensitization partially. CONCLUSION: We confirmed that D2 blockade was not effective for reversing sensitization. The reversal by clozapine is partially explained in terms of its strong 5-HT2 and weak D2 affinity. The partial reversal by fluoxetine seemed to be related to its serotonin-augmenting action.
Animals
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Antipsychotic Agents
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Brain
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Clozapine*
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Cocaine
;
Fluoxetine*
;
Haloperidol*
;
Humans
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Male
;
Mice
;
Mice, Inbred ICR
;
Motor Activity
;
Psychotic Disorders
9.The effects of electrical current from a micro-electrical device on tooth movement.
Dong Hwan KIM ; Young Guk PARK ; Seung Gu KANG
Korean Journal of Orthodontics 2008;38(5):337-346
OBJECTIVE: The purpose of this study was to determine whether an exogenous electric current to the alveolar bone surrounding a tooth being orthodontically treated can enhance tooth movement in human and to verify the effect of electric currents on tooth movement in a clinical aspect. METHODS: This study was performed on 7 female orthodontic patients. The electric appliance was set in the maxilla to provide a direct electric current of 20 micronA. The maxillary canine on one side was assigned as the experimental side, and the other as control. The experimental canine was provided with orthodontic force and electric current. The control side was given orthodontic force only. Electrical current was applied to experimental canines for 5 hours a day. The amount of canine movement was measured with an electronic caliper every week. RESULTS: The amount of orthodontic tooth movement in the experimental side during 4 weeks was greater by 30% compared to that of the control side. The amount of increase in tooth movement in the experimental side was statistically significant. The amount of tooth movement in the experimental side during the first two weeks was greater than that in the following two weeks. The amount of weekly tooth movement in the control side was decreased gradually. CONCLUSIONS: These results suggested that the exogenous electric current from the miniature electric device might accelerate orthodontic tooth movement by one third and have the potential to reduce orthodontic treatment duration.
Electronics
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Electrons
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Female
;
Humans
;
Maxilla
;
Tooth
;
Tooth Movement
10.The Feasibility of Robot-Assisted Laparoscopic Radical Cystectomy with Pelvic Lymphadenectomy: from the Viewpoint of Extended Pelvic Lymphadenectomy.
Seung Chul KANG ; Sung Gu KANG ; Hoon CHOI ; Young Hwii KO ; Jeong Gu LEE ; Je Jong KIM ; Seok Ho KANG ; Jun CHEON
Korean Journal of Urology 2009;50(9):870-878
PURPOSE: We evaluated the feasibility of robot-assisted laparoscopic radical cystectomy (RARC) with pelvic lymph node dissection (PLND), especially extended PLND (ePLND), during our initial experience with this technique. MATERIALS AND METHODS: From August 2007 to March 2009, prospective data were obtained from the 21 consecutive patients who underwent RARC with PLND at Korea University Hospital. Data included baseline characteristics, perioperative variables, pathological outcomes, and complications. Evidence of the lymph node yield curve was examined by using linear regression to compare the number of lymph nodes obtained. RESULTS: Among 21 patients who underwent RARC, 13 had ileal conduit urinary diversion and 8 had orthotopic neobladder. Standard PLND (sPLND) was performed in the first 15 patients, and ePLND was performed in the more recent 6 patients. The mean total operative time was 515.5+/-145.1 minutes, and the mean estimated blood loss was 346.8+/-205.9 ml. The mean time for PLND was 106.7+/-25.2 minutes in patients with ePLND and 72.1+/-14.1 minutes in patients with sPLND (p=0.001). All patients had negative surgical margins. The mean number of retrieved nodes was 23.5+/-12.8 (range, 8-50) in all patients: 38.6+/-10.8 (range, 29-50) in ePLND and 15.7+/-12.2 (range, 8-21) in sPLND. CONCLUSIONS: Perioperative data and oncologic features showed that RARC with PLND is feasible. Robot-assisted laparoscopic surgery is a safe and effective procedure with acceptable morbidity and good oncologic results from the viewpoint of PLND, especially ePLND.
Cystectomy
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Humans
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Korea
;
Laparoscopy
;
Linear Models
;
Lymph Node Excision
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Lymph Nodes
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Operative Time
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Prospective Studies
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Robotics
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Urinary Bladder Neoplasms
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Urinary Diversion