1.Arcuate Nucleus of the Hypothalamus:Anatomy, Physiology, and Diseases
Experimental Neurobiology 2023;32(6):371-386
The hypothalamus is part of the diencephalon and has several nuclei, one of which is the arcuate nucleus. The arcuate nucleus of hypothalamus (ARH) consists of neuroendocrine neurons and centrally-projecting neurons. The ARH is the center where the homeostasis of nutrition/metabolism and reproduction are maintained. As such, dysfunction of the ARH can lead to disorders of nutrition/metabolism and reproduction. Here, we review various types of neurons in the ARH and several genetic disorders caused by mutations in the ARH.
2.Intra-Individual Neuropsychological Test Variability : A Comparison of Patients with Schizophrenia, Their Siblings, and Healthy Controls.
Hyeji OH ; Kounseok LEE ; Seunghyong RYU ; Jihae NOH ; Juhyun PARK ; Hong CHOI ; Ji Hae KIM ; Kyung Sue HONG
Journal of Korean Neuropsychiatric Association 2014;53(6):379-385
OBJECTIVES: Intra-individual variability of cognitive performance across different tests or domains has been reported as an important index of cognitive function. The aim of the current study is to examine the intra-individual variability across different cognitive domains and tests in patients with schizophrenia, their unaffected siblings, and normal controls. We also compared the variability among three patient sub-groups divided according to the duration of illness. METHODS: Comprehensive neurocognitive tests were administered in order to stabilize patients with schizophrenia (n=129), healthy siblings (n=38) of the patients, and normal controls (n=110). Intra-individual variability was computed from the variance of the scores of six cognitive domains of the Measurement and Treatment Research to Improve Cognition in Schizophrenia consensus battery. We examined intra-individual variability across six factor-based cognitive scores and individual test scores of each cognitive domain. RESULTS: Compared to the normal control and sibling groups, patients showed significantly increased intra-individual variability across six cognitive domains and individual cognitive tests of each domain. Compared to the normal control, siblings showed significantly increased intra-individual variability only across individual tests of the processing of speed domain. Among patient sub-groups, those with the longest duration of illness (> or =11 years) showed significantly higher intra- individual variability across six cognitive domains and across individual tests of the processing of speed domain compared to the other two groups. CONCLUSION: This study identified cognitive dissonances across six cognitive domain schizophrenia patients. These cognitive characteristics were not observed in the sibling groups and seemed to progress during the course of illness.
Cognition
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Cognitive Dissonance
;
Consensus
;
Humans
;
Neuropsychological Tests*
;
Schizophrenia*
;
Siblings*
3.The Impact of Celebrity Suicide on Subsequent Suicide Rates in the General Population of Korea from 1990 to 2010.
Juhyun PARK ; Nari CHOI ; Seog Ju KIM ; Soohyun KIM ; Hyonggin AN ; Heon Jeong LEE ; Yu Jin LEE
Journal of Korean Medical Science 2016;31(4):598-603
The association between celebrity suicide and subsequent increase in suicide rates among the general population has been suggested. Previous studies primarily focused on celebrity suicides in the 2000s. To better understand the association, this study examined the impacts of celebrity suicides on subsequent suicide rates using the data of Korean celebrity suicides between 1990 and 2010. Nine celebrity suicides were selected by an investigation of media reports of suicide deaths published in three major newspapers in Korea between 1990 and 2010. Suicide mortality data were obtained from the National Statistical Office of Korea. Seasonal autoregressive integrated moving average models with intervention analysis were used to test the impacts of celebrity suicides, controlling for seasonality. Six of the 9 celebrity suicides had significant impacts on suicide rates both in the total population and in the same gender- or the same age-subgroups. The incident that occurred in the 1990s had no significant impact on the overall suicide rates, whereas the majority of the incidents in the 2000s had significant influences for 30 or 60 days following each incident. The influence of celebrity suicide was shown to reach its peak following the suicide death of a renowned actress in 2008. The findings may suggest a link between media coverage and the impact of celebrity suicide. Future studies should focus more on the underlying processes and confounding factors that may contribute to the impact of celebrity suicide on subsequent suicide rates.
Adult
;
Aged
;
*Famous Persons
;
Female
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Humans
;
Male
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Middle Aged
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Newspapers as Topic
;
Republic of Korea
;
Suicide/psychology/*statistics & numerical data
;
Young Adult
4.The Objective Test of Cochlear Dead Region Using Acoustic Change Complex: A Preliminary Report.
Soojin KANG ; Juhyun HAN ; Jihwan WOO ; Hee Sung PARK ; Il Joon MOON ; Kyusung CHOI ; Sung Hwa HONG
Korean Journal of Otolaryngology - Head and Neck Surgery 2018;61(11):573-579
BACKGROUND AND OBJECTIVES: Cochlear dead region (CDR) is a region in the cochlear where hearing loss has occurred due to damage to the inner hair cells and/or neurons. Recently, a subjective test involving a pure-tone test in the presence of threshold-equalizing noise (TEN) was introduced to identify CDR. However, for uncooperative patients, such a subjective method would be unsuitable and objective methods would be needed instead to detect CDR. The acoustic change complex (ACC) is an evoked potential elicited by changes in the ongoing sound. In this study, we developed an objective method of identifying CDR by combining ACC response with a TEN test, namely the TEN-ACC test, and investigated its feasibility in normal-hearing listeners. SUBJECTS AND METHOD: Ten normal-hearing subjects participated in this study. All subjects underwent both behavioral TEN test and electrophysiological TEN-ACC test. The stimuli for the TEN-ACC test consisted of TEN and embedded pure tones with different frequencies/signals to noise ratios (SNRs). To identify the thresholds, the range SNR of stimulation was varied from 0 to 20 dB, in stages of 4 dB. RESULTS: The ACC responses of all subjects who participated in this study were well elicited by stimuli developed for the TEN-ACC test. We confirm that the pure-tones embedded in TEN elicited the objective ACC response. CONCLUSION: The results of this study suggest that the novel TEN-ACC test can be applied to evoke ACC in normal-hearing listeners. Future research should incorporate hearing-impaired listeners to determine the feasibility of the TEN-ACC test as an objective method to identify CDR.
Acoustics*
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Evoked Potentials
;
Hair Cells, Auditory, Inner
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Hearing Loss
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Humans
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Methods
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Neurons
;
Noise
5.Enhancing the Antibacterial Effect of Erythrosine-Mediated Photodynamic Therapy with Ethylenediamine Tetraacetic Acid
MinKi CHOI ; Haeni KIM ; Siyoung LEE ; Juhyun LEE
Journal of Korean Academy of Pediatric Dentistry 2024;51(1):32-39
This study evaluated the additive impact of ethylenediamine tetraacetic acid (EDTA) on erythrosine-mediated photodynamic therapy (PDT) against Streptococcus mutans (S. mutans) biofilm by measuring colony-forming units and applying confocal laser scanning microscopy. Fifty-six bovine incisors, free from dental caries or structural defects, were utilized in this study. Dentin specimens were created by cutting with a low-speed diamond disk under a continuous flow of water, resulting in dimensions of 6.0 mm × 3.0 mm × 2.0 mm. The specimens were categorized into 4 groups: Control, EDTA, PDT, and EDTA + PDT. S. mutans ATCC 25175 was employed to establish biofilm on the dentin specimens. A 17% EDTA solution was applied for 1 min. For PDT, erythrosine served as the photosensitizer. Finally, a light-emitting diode source (385 - 515 nm) was employed in this study. The PDT group exhibited a significantly lower bacterial count than both the control and EDTA groups (p < 0.001). The EDTA + PDT group demonstrated a significantly reduced bacterial count compared to the other 3 groups (p < 0.001). This study demonstrated that EDTA enhances the antimicrobial efficacy of PDT on S. mutans biofilm. Even at a low concentration of photosensitizer, the combination of EDTA and PDT yields a significant antibacterial effect.
6.Comparative Evaluation of the Fluoride Releasing Ability and Microbial Attachment of Glass-Hybrid Restorative Material
MinKi CHOI ; Howon PARK ; Siyoung LEE ; Haeni KIM ; Juhyun LEE
Journal of Korean Academy of Pediatric Dentistry 2024;51(2):132-139
This study aimed to compare the fluoride-releasing ability and degree of microbial attachment of a newly developed glass-hybrid restorative material (GH) with those of a high-viscosity glass ionomer (HvGIC), resin-modified glass ionomer (RMGI), and composite resin (CR). In addition, the correlation between fluoride-releasing ability and microbial attachment between materials was evaluated. Specimens were prepared in a disc shape and divided into 4 groups according to the materials (GH, HvGIC, RMGI, and CR). The fluoride release experiments were performed in each group (n = 15). The amount of fluoride released was measured on days 1, 3, 7, 14, 28, and 42 after storage. For the microbial attachment experiment, 12 specimens were produced per group using Mutans Streptococci (S.mutans ), a cariogenic microorganism. S. mutans was cultured on the specimens for 24 hours, and the number of bacteria was measured. GH had the highest cumulative fluoride release and showed a significant difference when compared with RMGI (p = 0.001) and CR (p < 0.0001). Microbial attachment was the lowest in GH; however, no significant difference was observed between the materials (p = 0.169). There was no significant correlation between fluoride release from materials and microbial attachment (p > 0.05). From this perspective, remineralization of low-mineralized areas could be expected due to the high fluoride release of GH, and the effect of delaying the progression of dental caries could be predicted from the low cariogenic microbial attachment. Therefore, GH might be a useful restorative material for treating immature permanent teeth with hypomineralized enamel. However, further studies are needed about the degree of remineralization of hypomineralized areas after restoration and the capacity to recharge fluoride.
7.Single System Cutaneous Langerhans Cell Histiocytosis Mimicking Prurigo Nodularis
Juhyun CHUNG ; Kyujin YEOM ; Dongho KIM ; Myung Hwa KIM ; Byung Cheol PARK ; Mi Soo CHOI
Korean Journal of Dermatology 2024;62(2):110-113
Langerhans cell histiocytosis (LCH) is a rare inflammatory neoplasia of the dendritic cells that can affect the whole body and commonly affect the pediatric age. Adult onset LCH is relatively rare, and the cutaneous form without any other organ involvement is much more uncommon. A 62-year-old woman visited the clinic presenting pruritic erythematous papule and nodules on the whole body, from which she suffered for several years. Skin biopsy showed hyperkeratosis, mild acanthosis, intra-epidermal tumor cell infiltration, and band-like tumor cell infiltration. Cells infiltrating the epidermis and dermis showed characteristics consistent with Langerhans cells. Immunohistochemical analysis revealed tumor cells highlighted with CD1a and S-100, but not with CD68, and therefore, diagnosed as LCH. The patient showed no evidence of any other organ manifestation, which led the final diagnosis of single-system LCH. This case highlights a rare adult-onset cutaneous form of single-system LCH with skin manifestations very similar to prurigo nodularis.
8.A Case of Arteriovenous Malformation in the External Auditory Canal
Soo Jeong CHOI ; Juhyun LEE ; You-Na SUNG ; Gi Jung IM
Korean Journal of Otolaryngology - Head and Neck Surgery 2024;67(7):401-405
Benign vascular tumors are relatively common in the head and neck region, but are rarely found in the ear. Among vascular tumors, infantile hemangioma stands as the prevailing entity, characterized by a rapid initial proliferation of endothelial cells, succeeded by a gradual regression over the course of several years. In contrast, arteriovenous malformation (AVM) is a less common phenomenon, originating from peripheral vascular anomalies during embryogenesis, and it does not undergo spontaneous regression. Specifically, the occurrence of AVM within the external auditory canal are exceedingly uncommon. Here, we describe a case of a 49-year-old male patient who had a mass incidentally discovered in the external auditory canal, but refused initial treatment. He later returned as the mass enlarged. This case could have been clinically misdiagnosed as a hemangioma, but was ultimately diagnosed pathologically as an AVM.
9.Dehydroascorbic Acid Attenuates Ischemic Brain Edema and Neurotoxicity in Cerebral Ischemia: An in vivo Study.
Juhyun SONG ; Joohyun PARK ; Jae Hwan KIM ; Ja Yong CHOI ; Jae Young KIM ; Kyoung Min LEE ; Jong Eun LEE
Experimental Neurobiology 2015;24(1):41-54
Ischemic stroke results in the diverse phathophysiologies including blood brain barrier (BBB) disruption, brain edema, neuronal cell death, and synaptic loss in brain. Vitamin C has known as the potent anti-oxidant having multiple functions in various organs, as well as in brain. Dehydroascorbic acid (DHA) as the oxidized form of ascorbic acid (AA) acts as a cellular protector against oxidative stress and easily enters into the brain compared to AA. To determine the role of DHA on edema formation, neuronal cell death, and synaptic dysfunction following cerebral ischemia, we investigated the infarct size of ischemic brain tissue and measured the expression of aquaporin 1 (AQP-1) as the water channel protein. We also examined the expression of claudin 5 for confirming the BBB breakdown, and the expression of bcl 2 associated X protein (Bax), caspase-3, inducible nitric oxide synthase (iNOS) for checking the effect of DHA on the neurotoxicity. Finally, we examined postsynaptic density protein-95 (PSD-95) expression to confirm the effect of DHA on synaptic dysfunction following ischemic stroke. Based on our findings, we propose that DHA might alleviate the pathogenesis of ischemic brain injury by attenuating edema, neuronal loss, and by improving synaptic connection.
Aquaporins
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Aquaporin 1
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Ascorbic Acid
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bcl-2-Associated X Protein
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Blood-Brain Barrier
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Brain
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Brain Edema*
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Brain Injuries
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Brain Ischemia*
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Caspase 3
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Cell Death
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Claudin-5
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Dehydroascorbic Acid*
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Edema
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Neurons
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Nitric Oxide Synthase Type II
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Oxidative Stress
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Post-Synaptic Density
;
Stroke
10.The Association of Social Support with Health Status and Health Behavior among Rural Aged Population.
Boyoung JEON ; Hyejae LEE ; Changu SHON ; Namkwon KIM ; Aeryun KIM ; Jieun PARK ; Eunsang LEE ; Jeongwha LEE ; Juhyun CHOI
Journal of Agricultural Medicine & Community Health 2009;34(1):13-23
OBJECTIVE: The objective of this study was to evaluate the association of social support with health status and health behavior. METHODS: This study was conducted with 79 elderly people in Gunja-ri, Dongsan-myun, Chuncheon. We performed face to face interview which was composed of socio-demographic characteristics, social support, health status and health behavior. The association between social support and result variables was analysed by Chi-square test and logistic regression. We used SAS ver9.1 for statistic analysis. RESULTS: Mean age of the study population was 72.0+/-7.0, social support score was 14.3+/-4.7 with full marks of 20 and 36.25% of the total population were shown to have depression. When the social support score was changed, depression (p=0.0007) and physical exercise (p=0.0312) showed significant difference. The self-rated health status was significantly related to the relationship with family members (OR=0.25, 95% CI=0.07-0.95) and the quality of sleep was also significantly associated to the relationship with family members (OR=0.21, 95% CI=0.06-0.73). The physical exercise was done significantly less in the group 'without' close friends than in the group with 'many' close friends (OR=0.21, 95% CI=0.05-0.94) and the depression was significantly more in the group without community participation than in the group with community participation (OR=4.79, 95% CI=1.62-14.15). CONCLUSIONS: Through this study, we could conclude that the social support factors are associated with health status and health behavior. Therefore, to improve the health status of rural elderly, we need to approach to develop social support.
Aged
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Consumer Participation
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Depression
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Exercise
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Friends
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Health Behavior
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Humans
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Logistic Models
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Phenothiazines
;
Rural Health
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Sociology