• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.53-53
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• 2001

When repolarization of neuronal action potential does not decline monotonically but interrupted by additional depolarization, this prolonged depolarization phase is referred to afterdepolarization(ADP). ADP is considered to playa crucial role in the modulation of neuronal excitability, since it contributes to burst firing. We studied the ionic mechanisms underlying ADP in the soma of dentate granule cells, using rat hippocampal slice (300${\mu}{\textrm}{m}$ in thickness) prepared from 3- to 3-week-old SD rats.(omitted)

• IMMUNE NETWORK
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• 제20권3호
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• pp.24.1-24.14
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• 2020

Eosinophils are terminally differentiated cytotoxic effector cells that have a role in parasitic infections and allergy by releasing their granule-derived cytotoxic proteins. However, an increasing number of recent observations indicate that eosinophils are not only associated with the pathogenesis of a wide range of diseases, but also contribute to the maintenance of homeostatic responses in previously underappreciated diverse tissues, such as the gastrointestinal (GI) tract and adipose tissue. In this review, we describe biological characteristics of eosinophils, as their developmental properties, permissive proliferation and survival, degranulation activity, and migration properties enable them to distribute to both homeostatic and inflamed tissues. We describe pathologic aspects of eosinophils with a role in asthma and in various GI diseases, including eosinophilic GI disorders, inflammatory bowel disease, and radiation-induced enteropathy. Finally, we discuss the beneficial role of eosinophils, which contribute to the resolution of pathogenic conditions and to the modulation of homeostatic biologic responses.

• Experimental and Molecular Medicine
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• 제50권11호
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• pp.4.1-4.13
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• 2018

Two-pore domain $K^+$ (K2P) channels have been shown to modulate neuronal excitability. The physiological role of TWIK-1, the first identified K2P channel, in neuronal cells is largely unknown, and we reported previously that TWIK-1 contributes to the intrinsic excitability of dentate gyrus granule cells (DGGCs) in mice. In the present study, we investigated the coexpression of TWIK-1 and TASK-3, another K2P member, in DGGCs. Immunohistochemical staining data showed that TASK-3 proteins were highly localized in the proximal dendrites and soma of DGGCs, and this localization is similar to the expression pattern of TWIK-1. TWIK-1 was shown to associate with TASK-3 in DGGCs of mouse hippocampus and when both genes were overexpressed in COS-7 cells. shRNA-mediated gene silencing demonstrated that TWIK-1/TASK-3 heterodimeric channels displayed outwardly rectifying currents and contributed to the intrinsic excitability of DGGCs. Neurotensin-neurotensin receptor 1 (NT-NTSR1) signaling triggered the depolarization of DGGCs by inhibiting TWIK-1/TASK-3 heterodimeric channels, causing facilitated excitation of DGGCs. Taken together, our study clearly showed that TWIK-1/TASK-3 heterodimeric channels contribute to the intrinsic excitability of DGGCs and that their activities are regulated by NT-NTSR1 signaling.

• 대한약리학회지
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• 제32권1호
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• pp.13-21
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• 1996

세포내 칼슘농도는 신경세포의 다양한 기능에 매우 중요한 역할을 하고 있다. 본 연구에서는 일차배양한 마우스 소뇌과립세포에서 니코틴성 아세틸콜린 수용체가 특정 발생단계에 발현되고 세포내 칼슘의 농도조절에 관여하는 것을 관찰하였다. 니코틴에 의한 세포내 칼슘농도의 변화는 $^{45}Ca^{2+}$나 fura-2를 사용하여 형광법으로 측정하였다. 니코틴은 마우스 소뇌과립세포내 칼슘의 농도를 최대한 증가시키는 것으로 보인다. 반면에 일차배양한 Glia 세포들에서는 $^{45}Ca^{2+}$ 농도를 증가시키지 않았다. 세포내 칼슘농도에 미치는 니코틴의 효과는 NMDA 수용체에 대한 길항제에 의하여 억제되었다. 또한 Glutamate pyruvate transminase (GPT)를 사용하여 배양액의 글루타민산을 제거하면 니코틴효과가 소실되는 것이 관찰되었다. 이러한 결과는 니코틴에 의한 세포내 칼슘농도의 변화가 세포에서 유리된 글루타민산에 의한 간접적인 효과임을 암시한다. Fura-2를 사용한 형광법으로 실험한 결과 니코틴은 two phase로 세포내 칼슘농도를 증가시키는 것을 보여주었다. NMDA 수용체 길항제와 GPT는 단지 후기 plateau상만 억제하였다. 따라서 본 연구결과는 니코틴이 직접 니코틴성 아세틸콜린 수용체를 자극하여 일시적으로 세포내 칼슘농도를 증가시키고 글루타민산을 유리하여 NMDA 수용체를 활성화시킴으로써 세포내 칼슘농도를 지속적으로 증가시키는 것으로 보여진다. 이러한 결과는 니코틴성 아세틸콜린 수용체가 특정한 발생과정에 발현되어 세포내 칼슘농도 조절에 관여함으로써 신경발생과정에서 중요한 역할을 할 수 있음을 보여주고 있다. state를 나타내는 것을 알 수 있다. 또한 $[^3H]DPCPX$를 이용한 competitive binding assay에서 0.1 mM GTP는 효현제인 PIA의 apparent affinity를 감소시켰으며, DPCPX의 apparent affinity는 증가시키고, CGS-15943에는 아무런 영향을 미치지 않았다. 이것은 상기의 $[^{35}S]GTP_{\gamma}S$ binding의 결과를 뒤받침해 주는 결과라고 생각된다.요한 역할을 할 수 있으리라 사료된다.X>$Ca^{2+}$에 의하여 활성화되는 $K^+$ 통로를 개방시킴으로 세포내 $Ca^{2+}$을 감소시켜 뇌 기저동맥의 이완반응을 매개하는 것으로 사료된다. 함량을 조정하므로, 흉선세포의 apoptosis에 억제적으로 작용할 수 있음을 시사하는 것으로 사료된다. 영양액에 의하여는 회복됨을 볼 수 있었으며 $Mg^{++}$ 증가 영양액에서는 억제, TTX 동시 투여시에는 완전히 소실되었다. 이상의 실험결과로 흰쥐 해마에서 $A_1-adenosine$ 수용체를 통한 adenosine의 NE 유리 감소는 TEA 및 4AP에 예민한 $K^+$-통로가 관여하고 여기에는 세포외액의 Ca^{++}의 농도가 중요한 인자의 하나로 관여 하는 것으로 사료된다. 영상의 질을 크게 향상 시켜 줌으로 비가역 3구획모델에서의 PGA방법을 대체할 새로운 파라메터 영상구성방법으로 적합할 것이다.관계되며, YH439는 중금속으로 유도된 조직독성에 방어효과가 있음을 지지한다.총 아미노산의 순은

• Applied Microscopy
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• 제17권1호
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• pp.65-75
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• 1987

The ultrastructure of the cutaneous chromatophores and the origin of pigment granules in the goldfish, Carassius auratus L., are studied with electron microscope. Leucophores contain amorphous pigment granules, leucosomes and melanosomes contain oval shaped electron dense melanin pigment granules. These pigment granules are synthesized from the Golgi complexes of each chromatophores and released into the cytoplasm. Among the dermal chromatophores, another kind of dermal cells, named rER rich cells, are also observed. And pinocytotic vesicles are being formed only the inner surface of the chromatophores adhering to the rER rich cells. From these observations, such hypothesis are being possible that pigment materials are synthesized and transfered from the rER rich cells to dermal chromatophores by the pinocytosis. And next remodelizing mechanisms are carried out by the Golgi complexes of each chromatophores.

• Toxicological Research
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• 제28권2호
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• pp.107-112
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• 2012

Polychlorinated biphenyls (PCBs) are persistent and bioaccumulative environmental pollutants. Recently, it is suggested that neurotoxic effects such as motor dysfunction and impairment in memory and learning have been associated with PCB exposure. However, structure relationship of PCB congeners with neurotoxic effects remains unknown. Since PKC signaling pathway is implicated in the modulation of motor behavior as well as learning and memory and the role of PKC are subspecies-specific, we attempted to study the effects of structurally distinct PCBs on the total PKC activity as well as subspecies of PKC in cerebellar granule cell culture model. Cells were exposed to 0, 25 and 50 ${\mu}M$ of PCB-126, PCB-169, PCB-114, PCB-157, PCB-52 and PCB-4 for 15 min. Cells were subsequently analyzed by [$^3H$] phorbol ester binding assay or immunoblotted against PKC-${\alpha}$ and -${\varepsilon}$ monoclonal antibodies. While non-dioxin-like-PCB (PCB-52 and PCB-4) induced a translocation of PKC-${\alpha}$ and -${\varepsilon}$ from cytosol to membrane fraction, dioxin-like PCBs (PCB-126, -169, -114, -157) had no effects. [$^3H$] Phorbol ester binding assay also revealed structure-dependent increase similar to translocation of PKC isozymes. While PCB-4 induced translocation of PKC-${\alpha}$ and -${\varepsilon}$ was inhibited by ROS inhibitor, the pattern of translocation was not affected in presence of AhR inhibitor. It is suggested that PCB-4-induced PKC activity may not be mediated via AhR-dependent pathway. Taken together, our findings suggest that chlorination of ortho-position in PCB may be a critical structural moiety associated with neurotoxic effects, which may be preferentially mediated via non-AhR-dependent pathway. Therefore, the present study may contribute to understanding the neurotoxic mechanism of PCBs as well as providing a basis for establishing a better neurotoxic assessment.

• Tuberculosis and Respiratory Diseases
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• 제41권2호
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• pp.152-157
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• 1994

본 저자들은 양측성으로 반복되는 자연기흉 소견을 보인 21세 남자 환자에서BAL은 시행하여 조직구내 Birbeck granule을 찾음으로써 확진할 수 있었던 골 침범을 동반한 폐 조직구증 1예를 문헌 고찰과 함께 보고하는 바이다.

• Animal cells and systems
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• 제2권4호
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• pp.501-506
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• 1998

In the goby Micropercops swinhonis, the development of its egg's enveloping layers could be divided into 4 stages. In the earliest developmental period, stage I, there is a simple oocyte surrounded by a layer of squamous follicular cells. Stage II corresponds to the yolk vesicle stage of vitellogenesis. Here the initial follicular layer has become bilaminar with the retention of its outer squamous cell layer and the acquisition of an inner cuboidal cell layer just over the zona radiata. The number and size of the cuboidal cells increases throughout this stage. Stage III corresponds to the yolk granule stage of true vitellogenesis. Here the cuboidal cells begin to be replaced by columnar cells. As the oocyte grows, the columnar cells increase in size. The columnar cells produce cytoplasmic neutral mucins and by the end of this stage their cytoplasm has been filled with this mucin. In stage IV a single layer of squamous cells still remained as the outer follicular layer of the oocyte. The secretory activity of the inner follicular layers' columnar cells has ceased and they had lost their cell wall integrity and ended as a series of bullet-shaped, neutral mucin deposits.

• The Korean Journal of Physiology and Pharmacology
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• 제21권6호
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• pp.695-702
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• 2017

The sustained tonic currents ($I_{tonic}$) generated by ${\gamma}$-aminobutyric acid A receptors ($GABA_{A}Rs$) are implicated in diverse age-dependent brain functions. While various mechanisms regulating $I_{tonic}$ in the hippocampus are known, their combined role in $I_{tonic}$ regulation is not well understood in different age groups. In this study, we demonstrated that a developmental increase in GABA transporter (GAT) expression, combined with gradual decrease in $GABA_AR{\alpha}_5$ subunit, resulted in various $I_{tonic}$ in the dentate gyrus granule cells (DGGCs) of preadolescent rats. Both GAT-1 and GAT-3 expression gradually increased at infantile ($P_{6-8}$ and $P_{13-15}$) and juvenile ($P_{20-22}$ and $P_{27-29}$) stages, with stabilization observed thereafter in adolescents ($P_{34-36}$) and young adults ($P_{41-43}$). $I_{tonic}$ facilitation of a selective GAT-1 blocker (NO-711) was significantly less at $P_{6-8}$ than after $P_{13-15}$. The facilitation of $I_{tonic}$ by SNAP-5114, a GAT-3 inhibitor, was negligible in the absence of exogenous GABA at all tested ages. In contrast, $I_{tonic}$ in the presence of a nonselective GAT blocker (nipecotic acid, NPA) gradually decreased with age during the preadolescent period, which was mimicked by $I_{tonic}$ changes in the presence of exogenous GABA. $I_{tonic}$ sensitivity to L-655,708, a $GABA_AR{\alpha}_5$ subunit inverse agonist, gradually decreased during the preadolescent period in the presence of NPA or exogenous GABA. Finally, Western blot analysis showed that the expression of the $GABA_AR{\alpha}_5$ subunit in the dentate gyrus gradually decreased with age. Collectively, our results suggested that the $I_{tonic}$ regulation of altered GATs is under the final tune of $GABA_AR{\alpha}_5$ subunit activation in DGGCs at different ages.

• Applied Microscopy
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• 제17권1호
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• pp.83-97
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• 1987

In order to discriminate the enteroendocrine cell types in the mucosal epithelium of the normal duodenum of the Korean hedgehog (Erinaceus koreanus). The tissues were fixed in the mixture of 1% paraformaldehyde and 1% glutaraldehyde in phosphate buffer (pH 7.2), and postfixed in 2% osmium tetroxide (phosphate buffer, pH 7.2). They were embedded in Araldite, and the ultrathin sections were made by LKB-V ultratome following the inspection of semithin sections stained with toluidine blue-borax solutions. Ultrathin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100B electron microscope. At least six types of enteroendocrine cells distributed in the mucosal epithelium of the duodenum were identified according to their morphological characteristics mainly based on the size, shape, number and electron density of the secretory granules. Type I cells had moderately developed organelles. The secretory granules were pleomorphic ($370X510nm$), and the granule cores with high electron density were enveloped in limiting membrane and characterized by a narrow halo. Type II cells contained an indented nucleus and well-developed organelles. The secretory granules were round (350 nm) and classified in two kinds by electron density, moderate and high. Both granules were surrounded by limiting membrane and those with high electron density showed often a wide halo. Type III cells had an indented nucleus. The secretory granules with various electron density were round (220 nm) in shape. The granules with high electron density were enveloped in limiting membrane and characterized by a narrow halo, but those with low or moderate electron density had not been observed the limiting membrane. Type IV cells contained an indented nucleus and moderately developed organelles. The secretory granules were round (180 nm) in shape, and the granule cores with high electron density were enveloped in limiting membrane and showed often a wide halo. Type V cells had a large amount of rough endoplasmic reticulum. Secretory granules with low or moderate electron density were round (230 nm) in shape, and surrounded by limiting membrane and showed a narrow halo. Type VI cells contained an oval nucleus and well-developed organelles, especially Golgi complex. The secretory granules with high electron density were round (210 nm) in shape. The granules were enveloped in limiting membrane and showed often a wide halo.