• Title/Summary/Keyword: synapse

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Emotional and Behavioral characteristics of Early Childhood comparing Alpha wave and Beta wave Asymmetry at Prefrontal Lobe and with BIS/BAS (전전두엽 알파(α)파·베타(β)파 비대칭과 BIS/BAS에 기초한 유아들의 정서·행동 특성)

  • Lim, Hyun-Soon;Chae, Myung-Shin;Park, Pyong-Woon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.6
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    • pp.2588-2597
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    • 2011
  • The EEG asymmetry of prefrontal lobe has been researched to analyze the affect such as depression or anxiety and the behavioral characteristics such as BIS(Behavioral Inhibition System)/BAS(Behavioral Activational System) on the basiss of alpha band. However there has been several proposals about the importance of beta asymmetry pointing out the limitation of alpha asymmetry. Here, for 44 numbers of 4-year-old children, by comparing alpha asymmetry and beta asymmetry with BIS/BAS results respectively, we propose the way to classify the characteristics of affect and behavioral trend. We also found that BIS is related with beta-asymmetry, while BAS is related with alpha-asymmetry. As for the affective trait, we use the alpha asymmetry following the other results. Our results seem to be consistent with the other results that the synapse formation of young children is more active at the hemisphere than the right hemisphere.

A Study on the Action Potential Generations of the Vestibular Hair Cell Model with Negative Stiffness Feature (반강성 특성이 반영된 전정 유모세포 모델의 활동전위 생성에 관한 연구)

  • Kim, Dongyoung;Hong, Kihwan;Kim, Kyu-Sung;Lee, Sangmin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.9
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    • pp.190-199
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    • 2014
  • In this paper, the vestibular hair bundle feature model and integrated vestibular hair cell model were proposed. In conventional modeling studies of vestibular system, only partial mechanisms were modeled, such as the characteristics of the vestibular hair bundles without external forces or the action potential of synapse, and the study about action potential of vestibular afferent considering the characteristics of the vestibular hair bundle was not performed. The proposed integrated vestibular hair cell model reflects external forces considering negative stiffness features of each hair bundles with different regularities of hair cells and our model was compared with conventional model without external forces. As a result, irregular afferent and intermediate afferent with high ratio of firing frequency variations to the changes of external stimulation had small width of negative stiffness section, but the width of the negative stiffness of regular afferent with low ratio was similar to that of conventional negative stiffness features. And the proposed integrated vestibular hair cell model showed almost same results with conventional data with animal experiments in 11 chosen frequency bands. It is verified that our proposed hair bundle feature model is adequately modeled.

Sex Differences in Autism-Like Behavioral Phenotypes and Postsynaptic Receptors Expression in the Prefrontal Cortex of TERT Transgenic Mice

  • Kim, Ki Chan;Cho, Kyu Suk;Yang, Sung Min;Gonzales, Edson Luck;Valencia, Schley;Eun, Pyeong Hwa;Choi, Chang Soon;Mabunga, Darine Froy;Kim, Ji-Woon;Noh, Judy Kyoungju;Kim, Hee Jin;Jeon, Se Jin;Han, Seol-Heui;Bahn, Geon Ho;Shin, Chan Young
    • Biomolecules & Therapeutics
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    • v.25 no.4
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    • pp.374-382
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    • 2017
  • Autism spectrum disorder (ASD) remains unexplained and untreated despite the high attention of research in recent years. Aside from its various characteristics is the baffling male preponderance over the female population. Using a validated animal model of ASD which is the telomerase reverse transcriptase overexpressing mice (TERT-tg), we conducted ASD-related behavioral assessments and protein expression experiments to mark the difference between male and females of this animal model. After statistically analyzing the results, we found significant effects of TERT overexpression in sociability, social novelty preference, anxiety, nest building, and electroseizure threshold in the males but not their female littermates. Along these differences are the male-specific increased expressions of postsynaptic proteins which are the NMDA and AMPA receptors in the prefrontal cortex. The vGluT1 presynaptic proteins, but not GAD, were upregulated in both sexes of TERT-tg mice, although it is more significantly pronounced in the male group. Here, we confirmed that the behavioral effect of TERT overexpression in mice was male-specific, suggesting that the aberration of this gene and its downstream pathways preferentially affect the functional development of the male brain, consistent with the male preponderance in ASD.

Recent Advancement on the Knowledges of Meiotic Division (I) (減數分裂, 最近의 進步(I))

  • 한창열
    • Korean Journal of Plant Tissue Culture
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    • v.25 no.6
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    • pp.453-475
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    • 1998
  • During the 100 years since the initial discovery of meiotic phenomenon many brilliant aspects have been elucidated, but further researches based on light microscopy alone as an experimental tool have been found to have some limits and shortcomings. By the use of electron microscopy and armed with the advanced knowledges on modern genetics and biochemistry it has been possible to applu molecular technology in gaining information on the detailed aspects of meiosis. As synapsis takes place, a three-layered proteinous structure called the synatonemal complex starts to form in the space between the homologous chromosomes. To be more precise, it begins to form along the paired chromosomes early in the prophase I of meiotic division. The mechanism that leads to precise point-by-point pairing between homologous chromocomes division. The mechamism that leads to precise point-by-point pairing between homologous chromosomes remains to be ascertained. Several items of information, however, suggest that chromsome alignment leading to synapsis may be mediated somehow by the nuclear membrane. Pachytene bivalents in eukaryotes are firmly attached to the inner niclear membrane at both termini. This attached begins with unpaired leptotene chromosomes that already have developed a lateral element. Once attached, the loptotene chromosomes begin to synapse. A number of different models have been proposed to account for genetic recombination via exchange between DNA strands following their breakage and subsequent reunion in new arrangement. One of the models accounting for molecular recombination leading to chromatid exchange and chiasma formation was first proposed in 1964 by Holliday, and 30 years later still a modified version of his model is favored. Nicks are made by endomuclease at corresponding sites on one strant of each DNA duplex in nonsister chromatid of a bivalent during prophase 1 of meiosis. The nicked strands loop-out and two strands reassociate into an exchanged arrangement, which is sealed by ligase. The remaining intact strand of each duplex is nicked at a site opposite the cross-over, and the exposed ends are digested by exonuclease action. Considerable progress has been made in recent years in the effort to define the molecular and organization features of the centromere region in the yeast chromosome. Centromere core region of the DNA duplex is flanked by 15 densely packed nucleosomes on ons side and by 3 packed nucleosomes on the other side, that is, 2000 bp on one side and 400 400 bp in the other side. All the telomeres of a given species share a common DNA sequence. Two ends of each chromosome are virtually identical. At the end of each chromosome there exist two kinds of DNA sequence" simple telpmeric sequences and telpmere-associated sequencies. Various studies of telomere replication, function, and behabior are now in progress, all greatly aided by molecular methods. During nuclear division in mitosis as well as in meiosis, the nucleili disappear by the time of metaphase and reappear during nuclear reorganizations in telophase. When telophase begins, small nucleoli form at the NOR of each nucleolar-organizing chromosome, enlarge, and fuse to form one or more large nucleoli. Nucleolus is a special structure attached top a specific nucleolar-organizing region located at a specific site of a particular chromosome. The nucleolus is a vertical factory for the synthesis of rRNAs and the assenbly of ribosome subunit precursors.sors.

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Early Osteological Development of the Larvae and Juveniles in Sevenband Grouper, Epinephelus septemfasciatus (Pisces: Serranidae) (능성어 (Epinephelus septemfasciatus) 자치어의 골격발달)

  • Park, Jong Youn;Hong, Chang Gi;Cho, Jae Kwon;Son, Maeng Hyun;Han, Kyeong Ho;Park, Jae Min
    • Korean Journal of Ichthyology
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    • v.27 no.3
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    • pp.189-198
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    • 2015
  • This research has been launched in order to observe the osteological development of sevenband grouper, Epinephelus septemfasciatus larvae and juveniles and will be used for the basic data of phylogenetically systematics research. We got some samples of larvae and juveniles from a adult fish which belongs to the sea cage in Geomun-do, Yeosu-si, Jeolla-namdo province, and we have watched them. The average of breeding water temperature was $21.5{\sim}24.5^{\circ}C$ (average $23.0{\pm}1.5^{\circ}C$). In yolk-sac larvae just after hatching, ossification was not observed at all, and when the average total length reached 2.66 mm, the premaxillary and maxillary forming the upper jaw, dentary forming the lower jaw, and parasphenoid forming the skull base were ossified. In addition, the preopercle and opercle forming the opercular region began to be ossified. The caudal skeleton supporting the caudal fin is built with the caudal complex consisting of the malleus and incus. Until the average total length reached 2.59 mm, ossification did not occur at all and the urostyle bent at 45-degree angle. As to the ossification of the pterygiophore, when the average total length was 6.12 mm, the first interhemal spine began to be ossified in articulation with two spines of the anal fin, and the synapse also began to be ossified in articulation with two spines of the dorsal fin. When the average total length was 21.9 mm, individuals with completed ossification of the interhemal spines and synaptic clefts began to appear.

A Convenient Synthesis of N', N'-Disubstituted N-Fluorophenylformamidines by Using Microwave and Their Insecticidal Activities (마이크로웨이브를 이용한 N', N'-Disubstituted N-Fluorophenylformamidine 유도체의 편리한 합성과 살충활성)

  • Lee, Dong-Guk;Chung, Kun-Hoe;Ko, Young-Kwan;Ryu, Jae-Wook;Woo, Jae-Chun;Koo, Dong-Wan;Choi, Yong-Ho;Park, No-Joong;Kim, Jin-Ju;Kim, Tae-Joon
    • The Korean Journal of Pesticide Science
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    • v.13 no.2
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    • pp.117-125
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    • 2009
  • Phenylformamidine derivatives are well known as insecticides for their specific activity against the insects. It has now been established that they show insecticidal activity as agonists on the octopamine receptor which is located in the synapse membrane. The reaction of triethylorthoformate and fluoroanilines gave formimidates (1) in good yields and N',N'-Disubstituted N-fluorophenylformamidine derivatives were synthesized more easily by using microwave. This microwave reaction condition gave products in high yields and faster reaction time than conventional methods. All the compounds were screened for their biological activity agaist harmful insects of plant hoppers, moths, aphids and mites. Synthetic compounds of 2-I-a, 2-I-c, 2-I-d, 2-II-d showed good activity against mites and plant hoppers.

The expression of Foxp3 protein by retroviral vector-mediated gene transfer of Foxp3 in C57BL/6 mice (C57BL/6 마우스에서 Retroviral 벡터를 이용한 Foxp3 유전자의 도입에 의한 Foxp3 단백의 발현 양상)

  • Hwang, Insun;Ha, Danbee;Bing, So Jin;Jeon, Kyong-Leek;Ahn, Ginnae;Kim, Dae Seung;Cho, Jinhee;Lim, Jaehak;Im, Sin-Hyeog;Hwang, Kyu-Kye;Jee, Youngheun
    • Korean Journal of Veterinary Research
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    • v.52 no.3
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    • pp.183-191
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    • 2012
  • The maintenance of peripheral immune tolerance and prevention of chronic inflammation and autoimmune disease require $CD4^{+}CD25^{+}$ T cells (regulatory T cells). The transcription factor Foxp3 is essential for the development of functional, regulatory T cells, which plays a prominent role in self-tolerance. Retroviral vectors can confer high level of gene transfer and transgene expression in a variety of cell types. Here we observed that following retroviral vector-mediated gene transfer of Foxp3, transductional Foxp3 expression was increased in the liver, lung, brain, heart, muscle, spinal cord, kidney and spleen. One day after vector administration, high levels of transgene and gene expression were observed in liver and lung. At 2 days after injection, transductional Foxp3 expression level was increased in brain, heart, muscle and spinal cord, but kidney and spleen exhibited a consistent low level. This finding was inconsistent with the increase in both $CD4^{+}CD25^{+}$ T cell and $CD4^{+}Foxp3^{+}$ T cell frequencies observed in peripheral immune cells by fluorescence-activated cell-sorting (FACS) analysis. Retroviral vector-mediated gene transfer of Foxp3 did not lead to increased numbers of $CD4^{+}CD25^{+}$ T cell and $CD4^{+}Foxp3^{+}$ T cell. These results demonstrate the level and duration of transductional Foxp3 gene expression in various tissues. A better understanding of Foxp3 regulation can be useful in dissecting the cause of regulatory T cells dysfunction in several autoimmune diseases and raise the possibility of enhancing suppressive functions of regulatory T cells for therapeutic purposes.

The Shape of Synaptic Vesicles in the Tooth Pulp Afferent Terminals and P-endings in the Rat Trigeminal Nucleus Principalis (흰쥐의 삼차신경주감각핵에서 치수유래 일차들신경종말 및 이와 연접하는 연접이전신경종말의 연접소포 형태 비교)

  • Kim, Yun-Sook;Paik, Sang-Kyoo;Kwak, Woo-Kyung;Cho, Yi-Sul;Kim, Ji-Man;Park, Mae-Ja;Bae, Yong-Chul
    • Applied Microscopy
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    • v.38 no.4
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    • pp.375-382
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    • 2008
  • In order to investigate shape of synaptic vesicles of the tooth pulp afferent boutons and their presynaptic endings (p-endings), and the neuroactive substance of the p-endings in the trigeminal nucleus principalis, rat incisor tooth pulp afferents were labeled by the horseradish peroxidase (HRP) and quantitative ultrastructural analysis and postembedding immunogold labeling were performed. Labeled tooth pulp afferent boutons contained clear, spherical synaptic vesicles (diameter: $45{\sim}55\;nm$) and occasionally dense core vesicles(diameter: $80{\sim}120\;nm$). They formed symmetrical synapses with unlabeled axon terminals (p-endings) containing pleomorphic synaptic vesicles. The ratio of short to long diameter (form factor) of synaptic vesicles of pulp afferent boutons was 0.6 to 0.99, whereas that of p-endings was 0.25 to 0.99. In addition, most of the p-endings showed GABA-like immunoreactivity. These results indicate that the shape of synaptic vesicles is quite different between the tooth pulp afferent boutons and p-endings, and the p-endings may contain GABA as a neuroactive substance in the trigeminal nucleus principalis.

Impulse Trafficking in Neurons of the Mesencephalic Trigeminal Nucleus

  • Saito, Mitsuru;Kang, Young-Nam
    • International Journal of Oral Biology
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    • v.31 no.4
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    • pp.113-118
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    • 2006
  • In the primary sensory neuron of the mesencephalic trigeminal nucleus (MTN), the peripheral axon supplies a large number of annulospiral endings surrounding intrafusal fibers encapsulated in single muscle spindles while the central axon sends only a few number of synapses onto single ${\alpha}-motoneurons({\alpha}-MNs)$. Therefore, the ${\alpha}-{\gamma}$ linkage is thought to be very crucial in the jaw-closing movement. Spike activity in a ${\gamma}-motoneuron\;({\gamma}-MN)$ would induce a large number of impulses in single peripheral axons by activating many intrafusal fibers simultaneously, subsequently causing an activation of ${\alpha}-MNs$ in spite of the small number of synapses. Thus, the activity of ${\gamma}-MNs$ may be vital for modulation of jaw-closing movements. Independently of such a spindle activity modulated by ${\gamma}-MNs$, somatic depolarization in MTN neurons is known to trigger the oscillatory spike activity. Nevertheless, the trafficking of these spikes arising from the two distinct sources of MTN neurons is not well understood. In this short review, switching among multiple functional modes of MTN neurons is discussed. Subsequently, it will be discussed which mode can support the ${\alpha}-{\gamma}$ linkage. In our most recent study, simultaneous patch-clamp recordings from the soma and axon hillock revealed a spike-back-propagation from the spike-initiation site in the stem axon to the soma in response to a somatic current pulse. The persistent $Na^+$ current was found to be responsible for the spike-initiation in the stem axon, the activation threshold of which was lower than those of soma spikes. Somatic inputs or impulses arising from the sensory ending, whichever trigger spikes in the stem axon first, would be forwarded through the central axon to the target synapse. We also demonstrated that at hyperpolarized membrane potentials, 4-AP-sensitive $K^+$ current ($IK_{4-AP}$) exerts two opposing effects on spikes depending on their origins; the suppression of spike initiation by increasing the apparent electrotonic distance between the soma and the spike-initiation site, and the facilitation of axonal spike invasion at higher frequencies by decreasing the spike duration and the refractory period. Through this mechanism, the spindle activity caused by ${\gamma}-MNs$ would be safely forwarded to ${\alpha}-MNs$. Thus, soma spikes shaped differentially by this $IK_{4-AP}$ depending on their origins would reflect which one of the two inputs was forwarded to the target synapses.

Development of the Hippocampal Learning Algorithm Using Associate Memory and Modulator of Neural Weight (연상기억과 뉴런 연결강도 모듈레이터를 이용한 해마 학습 알고리즘 개발)

  • Oh Sun-Moon;Kang Dae-Seong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.4 s.310
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    • pp.37-45
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    • 2006
  • In this paper, we propose the development of MHLA(Modulatory Hippocampus Learning Algorithm) which remodel a principle of brain of hippocampus. Hippocampus takes charge auto-associative memory and controlling functions of long-term or short-term memory strengthening. We organize auto-associative memory based 3 steps system(DG, CA3, CAl) and improve speed of learning by addition of modulator to long-term memory learning. In hippocampal system, according to the 3 steps order, information applies statistical deviation on Dentate Gyrus region and is labelled to responsive pattern by adjustment of a good impression. In CA3 region, pattern is reorganized by auto-associative memory. In CAI region, convergence of connection weight which is used long-term memory is learned fast by neural networks which is applied modulator. To measure performance of MHLA, PCA(Principal Component Analysis) is applied to face images which are classified by pose, expression and picture quality. Next, we calculate feature vectors and learn by MHLA. Finally, we confirm cognitive rate. The results of experiments, we can compare a proposed method of other methods, and we can confirm that the proposed method is superior to the existing method.