• Title/Summary/Keyword: brain activity

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Effect of t-butylhydroperoxide on $Na^+-dependent$ Glutamate Uptake in Rabbit Brain Synaptosome

  • Lee, Hyun-Je;Kim, Yong-Keun
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.4
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    • pp.367-376
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    • 1997
  • The effect of an organic peroxide, t-butylhydroperoxide (t-BHP), on glutamate uptake was studied in synaptosomes prepared from cerebral cortex. t-BHP inhibited the $Na^+-dependent$ glutamate uptake with no change in the $Na^+-independent$ uptake. This effect of t-BHP was not altered by addition of $Ca^{2+}$ channel blockers (verapamil, diltiazem and nifedipine) or $PLA_2$ inhibitors (dibucaine, butacaine and quinacrine). However, the effect was prevented by iron chelators (deferoxamine and phenanthroline) and phenolic antioxidants (N,N'-diphenyl-phenylenediamine, butylated hydroxyanisole, and butylated hydroxytoluene). At low concentrations (<1.0 mM), t-BHP inhibited glutamate uptake without altering lipid peroxidation. Moreover, a large increase in lipid peroxidation by $ascorbate/Fe^{2+}$ was not accompanied by an inhibition of glutamate uptake. The impairment of glutamate uptake by t-BHP was not intimately related to the change in $Na^+-K+-ATPase$ activity. These results suggest that inhibition of glutamate uptake by t-BHP is not totally mediated by peroxidation of membrane lipid, but is associated with direct interactions of glutamate transport proteins with t-BHP metabolites. The $Ca^{2+}$ influx through $Ca^{2+}$ channel or $PLA_2$ activation may not be involved in the t-BHP inhibition of glutamate transport.

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Panosialins, Inhibitors of Enoyl-ACP Reductase from Streptomyces sp. AN1761

  • Kwon, Yun Ju;Sohn, Mi-Jin;Oh, Taegwon;Cho, Sang-Nae;Kim, Chang-Jin;Kim, Won-Gon
    • Journal of Microbiology and Biotechnology
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    • v.23 no.2
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    • pp.184-188
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    • 2013
  • In the continued search for inhibitors of enoyl-acyl carrier protein (ACP) reductase, we found that four acylbenzenediol sulfate metabolites from Streptomyces sp. AN1761 potently inhibited bacterial enoyl-ACP reductases of Staphylococcus aureus, Streptococcus pneumoniae, and Mycobacterium tuberculosis. Their structures were identified as panosialins A, B, wA, and wB by MS and NMR data. They showed stronger inhibition against S. aureus FabI and S. pneumoniae FabK with $IC_{50}$ of 3-5 ${\mu}M$ than M. tuberculosis InhA with $IC_{50}$ of 9-12 ${\mu}M$. They also exhibited a stronger antibacterial spectrum on S. aureus and S. pneumoniae than M. tuberculosis. In addition, the higher inhibitory activity of panosialin wB than panosialin B on fatty acid biosynthesis was consistent with that on bacterial growth, suggesting that they could exert their antibacterial activity by inhibiting fatty acid synthesis.

Comparative study on Hsp25 expression in Mongolian gerbil and mouse cerebellum

  • Lee, Heang-Yeon;Kim, Seong-Hwan;Lee, Jae-Bong;Shin, Chang-Ho
    • Korean Journal of Veterinary Service
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    • v.29 no.4
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    • pp.469-482
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    • 2006
  • The term 'heat shock protein (Hsps)' was derived from the fact that these proteins were initially discovered to be induced by hyperthermic conditions. In response to a range of stressful stimuli, including hyperthermia, immobilization, UV radiation, amino acid analogues, arsenite, various chemicals, and drugs the mammalian brain demonstrates a rapid and intense induction of the heat shock protein. Moreover, Hsps were expressed on the various pathological conditions including trauma, focal or global ischemia, hypoxia, infarction, infections, starvation, and anoxia. Especially, Hsp25 has a protective activity, facilitated by the ability of the protein to decrease the intracellular levels of reactive oxygen species (ROS) as well as its chaperone activity, which favors the degradation of oxidized proteins. Recently, it has clearly demonstrated that Hsp25 is constitutively expressed in the adult mouse cerebellum by parasagittal bands of purkinje cells in three distinct regions, the central zone (lobule VI-VII) and nodular zone (lobule IX-X), and paraflocculus. The Mongolian gerbil has been introduced into stroke study model because of its unique brain vasculature. There are no significant connections between the basilarvertebral system and the carotid system. This anatomy feature renders the mongolian gerbil susceptible to forebrain ischemia-induced seizure. The present study is designed to examine the pattern of Hsp25 expression in the cerebellum of this animal in comparison with that in mouse.

Spatial Focalization of Zen-Meditation Brain Based on EEG

  • Liu, Chuan-Yi;Lo, Pei-Chen
    • Journal of Biomedical Engineering Research
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    • v.29 no.1
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    • pp.17-24
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    • 2008
  • The aim of this paper is to report our preliminary results of investigating the spatial focalization of Zen-meditation EEG (electroencephalograph) in alpha band (8-13 Hz). For comparison, the study involved two groups of subjects, practitioners (experimental group) and non-practitioners (control group). To extract EEG alpha rhythm, wavelet analysis was applied to multi-channel EEG signals. Normalized alpha-power vectors were then constructed from spatial distribution of alpha powers, that were classified by Fuzzy C-means based algorithm to explore various brain spatial characteristics during meditation (or, at rest). Optimal number of clusters was determined by correlation coefficients of the membership-value vectors of each cluster center. Our results show that, in the experimental group, the incidence of frontal alpha activity varied in accordance with the meditation stage. The results demonstrated three different spatiotemporal modules consisting with three distinctive meditation stages normally recognized by meditation practitioners. The frontal alpha activity in two groups decreased in different ways. Particularly, monotonic decline was observed in the control group, and the experimental group showed increasing results. The phenomenon might imply various mechanisms employed by meditation and relaxation in modulating parietal alpha.

Sex differences in QEEG in adolescents with conduct disorder and psychopathic traits

  • Calzada-Reyes, Ana;Alvarez-Amador, Alfredo;Galan-Garcia, Lidice;Valdes-Sosa, Mitchell
    • Annals of Clinical Neurophysiology
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    • v.21 no.1
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    • pp.16-29
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    • 2019
  • Background: Sex influences is important to understand behavioral manifestations in a large number of neuropsychiatric disorders. We found electrophysiological differences specifically related to the influence of sex on psychopathic traits. Methods: The resting electroencephalography (EEG) activity and low-resolution brain electromagnetic tomography (LORETA) for the EEG spectral bands were evaluated in 38 teenagers with conduct disorder (CD). The 25 male and 13 female subjects had psychopathic traits as diagnosed using the Antisocial Process Screening Device. All of the included adolescents were assessed using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) criteria. The visually inspected EEG characteristics and the use of frequency-domain quantitative analysis techniques are described. Results: Quantitative EEG (QEEG) analysis showed that the slow-wave activities in the right frontal and left central regions were higher and the alpha-band powers in the left central and bitemporal regions were lower in the male than the female psychopathic traits group. The current source density showed increases in paralimbic areas at 2.73 Hz and decreases in the frontoparietal area at 9.37 Hz in male psychopathics relative to female psychopathics. Conclusions: These findings indicate that QEEG analysis and techniques of source localization can reveal sex differences in brain electrical activity between teenagers with CD and psychopathic traits that are not obvious in visual inspections.

Morus Nigra Extract Attenuates Cognition Impairment and GABAergic Interneuron Degeneration in Aged Rat Brain

  • Lee, Joo Hee;Kim, Yoonju;Song, Min Kyung;Kim, Youn-Jung
    • Journal of Korean Biological Nursing Science
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    • v.24 no.2
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    • pp.77-85
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    • 2022
  • Purpose: Aging process comes with cognitive impairment due to decreased neuronal cell number, activity, and neuronal circuit. Alteration of inhibitory neurons contributes to cognitive impairment in normal aging and is responsible for disrupting the excitation/inhibition balance by reducing the synthesis of gamma-aminobutyric acid (GABA). Morus nigra (Mulberry) is a natural physiologically active substance that has been proven to have anti-oxidant, anti-diabetic, and anti-inflammatory effects through many studies. This study aimed to evaluate the effects of the mulberry extract (ME) on cognitive function through anti-oxidant enzyme and GABAergic neuronal activity in aged rat brain. Methods: Sprague Dawley rats were randomly assigned as the young group (8 weeks, n= 8), aging group (67 weeks, n= 8), and aging+ mulberry extract group (67 weeks, n= 8). The aging+ mulberry extract group was orally administered 500 mg/kg/d mulberry extract for 6 weeks. Results: The aging+ mulberry extract group improved spatial and short-term memory. The antioxidant potential of ME increased the expression of superoxide dismutase-1 (SOD-1) and decreased inducible nitric oxide synthase (iNOS). Also, the aging+ mulberry extract group significantly increased the expression of GABAergic interneuron in hippocampus cornu ammonis1 (CA1) compared to the aging group. Conclusion: The number of GABAergic inhibitory interneurons was deceased and memory functions in the aging process, but those symptoms were improved and restored by mulberry extract administration.

Anti-inflammatory Effects of Herbal Formula KCNS-001 for Mitigating Atopic Dermatitis (한약조성물 KCNS-001이 자유라디칼과 염증매개인자에 미치는 영향)

  • Lee, Jeong-Bok;Choi, Jae-Hwan;Bang, Ok-Sun;Yu, Young-Beob
    • The Korea Journal of Herbology
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    • v.24 no.3
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    • pp.97-102
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    • 2009
  • Objectives : We determined the anti-inflammatory activity of KCNS-001 that is a herbal formula including 6 medicinal plants and that are used to mitigate atopic dermatitis in oriental medicine. Methods : To evaluate anti-inflammatory effect of KCNS-001, we measured the production of reactive oxygen species (ROS), nitric oxide (NO) and cyclooxygenase-2 (COX-2) in LPS-activated Raw 264.7 cells. Cell viability was determined by MTT assay. The concentrations of ROS and relative level of NO were measured with DPPH assay and Griess reagent, respectively. COX-2 and TNF-$\alpha$ were detected by enzyme immuno assay (EIA) and enzyme-linked immunosorbent assay (ELISA). Results : ROS and NO production were reduced by KCNS-001 in a dose-dependent manner. KCNS-001 significantly inhibited activity of COX-2 and suppressed the release of tumor necrosis factor-alpha (TNF-$\alpha$). Conclusions : These results indicate that the KCNS-001 may have an anti-inflammatory agent for the treatment of various inflammatory disease.

On the Analysis of ACQ Effect in Serious Game Contents by Listening Type (기능성 게임콘텐츠의 음향 청취방법이 뇌 활성화지수에 미치는 효과)

  • Min, Yong-Sik;Yoo, Hunter
    • The Journal of the Acoustical Society of Korea
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    • v.29 no.4
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    • pp.237-242
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    • 2010
  • To do an experimental analysis in this paper, we divided two non-equivalent control groups, such as pre and post test groups for difference listening types by serious game contents. From these test groups, we can achieve the most ability of its activity quotient (ACQ) effect is a phonic type and the next one is an aural type. The purpose of this paper is focused on the quantitative analysis of the human's brain quotient (BQ) derived from serious educational game contents.

Inhibitory Effects of Bioactive Fractions Containing Protoberberine Alkaloids from the Roots of Coptis japonica on Monoamine Oxidase Activity

  • Lee, Myung-Koo;Lee, Sang-Seon;Ro, Jai-Seup;Lee, Kyong-Soon;Kim, Hack-Seang
    • Natural Product Sciences
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    • v.5 no.4
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    • pp.159-161
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    • 1999
  • The effects of bioactive fractions containing protoberberine alkaloids from Coptis japonica on monoamine oxidase (MAO) activity were investigated. The MAO was obtained from the mitochondrial fraction of mouse brain. The butanol fraction from Coptis japonica was fractionated into separate bioactive fraction (Fr I-IV) by silica gel column chromatography. MAO activity was strongly inhibited by Fr III and IV, which mainly contain protoberberine alkaloids such as berberine, palmatine and coptisine. These results indicated that the protoberberine alkaloids from Coptis japonica had an inhibitory effect on MAO activity.

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Changes in the Activities of Cholinesterase in Serum, Brain and Spinal cord Injection of Parathion in Rats (Parathion을 투여한 Rat의 혈청, 척수 및 뇌 Cholinesterase 활성도의 변동 조사)

  • 도재철;이창우;손재권;정종식
    • Korean Journal of Veterinary Service
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    • v.14 no.1
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    • pp.71-77
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    • 1991
  • Parathion is widely used in agriculture, but it is highly toxic and now clear that parathion behaves like a cholinergic drug by inhibiting the enzyme cholinesterase. In order to know acute toxicity and the changes of cholinesterase activity according to time lapsed in Sprague-Dawley rats injected single with half dose to LD$_{50}$ of parathion, cholinesterase activities in serum, spinal cord, whole brain and median lethal dose between sex difference were investigated. The results obtained were summerized as follows ; 1. 4LD_{50}$ values of parathion given intraperitoneally to male and female rats were 10.5mg / kg(95% confidence limits, 6.6-16.8mg/ kg) and 3.3mg/ kg(95% confidence limits, 1.9-5.6mg/ kg). 2. The inhibition rate of cholinesterase activities in serum of parathion-injected rats according to time lapsed were peakly decreased to 35.4%(male) and 32.4%(female) after 1 hour in comparison to control group, but cholinesterase activities were completely recovered after 48 hours. 3. The inhibition rate of cholinesterase activities in spinal cord of parathion-injected rats according to time lapsed were peakly decreased to 31.1% (male) and 36.3% (female) after 30 minutes in comparison to control group, but cholinesterase activities were completely recovered after 48 hours. 4. The inhibition rate of cholinesterase activities in whole brain of parathion -injected rats according to time lapsed were peakly decreased to 32.2%(male) and 42.6%(female) after 1 hour in comparison to control group, but cholinesterase activities were completely recovered after 48 hours.s.

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