• Title/Summary/Keyword: Granule

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Subacute Nicotine Exposure in Cultured Cerebellar Cells Increased the Release and Uptake of Glutamate

  • Lim, Dong-Koo;Park, Sun-Hee;Choi, Woo-Jeoung
    • Archives of Pharmacal Research
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    • v.23 no.5
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    • pp.488-494
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    • 2000
  • Cerebellar granule and glial cells prepared from 7 day-old rat pups were used to investigate the effects of sub-acute nicotine exposure on the glutamatergic nervous system. These cells were exposed to nicotine in various concentrations for 2 to 10 days in situ. Nicotine-exposure did not result in any changes in cerebellar granule and glial cell viability at concentrations of up to 500 $\mu\textrm{M}$. In cerebellar granule cells, the basal extracellular levels of glutamate, aspartate and glycine were enhanced in the nicotine-exposed granule cells. In addition, the responses of N-methyl-D-aspartate (NMDA)-induced glutamate release were enhanced at low NMDA concentrations in the nicotine-exposed granule cells. However, this decreased at higher NMDA concentrations. The glutaminase activity was increased after nicotine exposure. In cerebellar glial cells, glutamate uptake in the nicotine-exposed glial cells were either increased at low nicotine exposure levels or decreased at higher levels. The inhibition of glutamate uptake by L-trans-pyrollidine-2,4-dicarboxylic acid (PDC) was lower in glial cells exposed to 50 $\mu\textrm{M}$ nicotine. Glutamine synthetase activity was lower in glial cells exposed to 100 or 500 $\mu\textrm{M}$ of nicotine. These results indicate that the properties of cerebellar granule and glial cells may alter after subacute nicotine exposure. Furthermore, they suggest that nicotine exposure during development may modulate glutamatergic nervous activity.

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Calcium Influx is Responsible for Afterdepolarizations in Rat Hippocampal Dentate Granule Cells

  • Park, Won-Sun;Lee, Suk-Ho
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.3
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    • pp.143-147
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    • 2002
  • Granule cells in dentate gyrus of hippocampus relay information from entorhinal cortex via perforant fiber to pyramidal cells in CA3 region. Their electrical activities are known to be closely associated with seizure activity as well as memory acquisition. Since action potential is a stereotypic phenomena which is based on all-or-none principle of $Na^+$ current, the neuronal firing pattern is mostly dependent on afterpotentials which follows the stereotypic $Na^+$ spike. Granule cells in dentate gyrus show afterdepolarization (ADP), while interneurons in dentate gyrus have afterhyperpolarizaton. In the present study, we investigated the ionic mechanism of afterdepolarization in hippocampal dentate granule cell. Action potential of dentate granule cells showed afterdepolarization, which was characterized by a sharp notch followed by a depolarizing hump starting at about $-49.04{\pm}1.69\;mV\;(n=43,\;mean{\pm}SD)$ and lasting $3{\sim}7$ ms. Increase of extracellular $Ca^{2+}$ from 2 mM to 10 mM significantly enhanced the ADP both in amplitude and in duration. A $K^+$ channel blocker, 4-aminopyridine (4-AP, 2 mM), enhanced the ADP and often induced burst firings. These effects of 10 mM $Ca^{2+}$ and 4-AP were additive. On the contrary, the ADP was significantly suppressed by removal of external $Ca^{2+},$ even in the presence of 4-AP (2 mM). A $Na^+$ channel blocker, TTX (100 nM), did not affect the ADP. From these results, it is concluded that the extracellular $Ca^{2+}$ influx contributes to the generation of ADP in granule cells.

Optimization of powder compaction parameters for the pressureless sintered ZTA (상압소결 ZTA의 분말 성형 공정 최적화)

  • 신동우;김경도;박삼식;임창성;이수완
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.8 no.2
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    • pp.356-364
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    • 1998
  • The dependence of green and sintered densities of Zirconia-Toughened Alumina ($ZTA:\;Al_2O_3/\;15\;vol{%}\;ZrO_2$) on the properties of spray-dried granules was studied thoroughly to establish the optimum compaction condition leading to high reproducibility in the light of sintered density. The sphericity, mean size, degree of hollow occurrence and moisture content of spray-dried granules were largely different in between the granule containing binder and the ones with no binder. The effect of these differences in the characteristic of granules on the compaction behavior was examined in terms of the compaction pressure from 80 MPa to 120 MPa 10 MPa increment and the compaction method, i.e., uniaxial and cold isostatic pressing. This work confirmed that the reproducibility of sintered density caused by the variation of granule property could be improved by the optimization of compaction process. The variation of sintered density was controlled within 1 % deviation by compacting the granules under a relatively low pressure of 80 MPa in an uniaxial forming and subsequent cold isostatic pressing at high pressure of 500 MPa.

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Ultrastructural Study on the Parenchymal Cell of Korean Planaria (Dugesia japonica) (한국산 플라나리아(Dugesia japonica Ichikawa et Kawakatsu) 유조직의 미세구조에 관한 연구)

  • 장남섭
    • The Korean Journal of Zoology
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    • v.30 no.1
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    • pp.53-70
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    • 1987
  • The morphological study on the parenchymal cells in the adult planaria performed to observe their cytochemical and ultrastructural characteristics. The results are as follows. Nine types of cells are found in parenchyma. 1. Free parenchymal cell: These cells contain several chromatoid bodies around the nucleus. Heterochromatins are evenly dispersed in large nucleus. These cells are abundant in free ribosomes. 2. Fixed parenchymal cells: These cells have well-developed granular endoplasmic reticulum, mitochondria and Golgi complex but they contain the cytosols exhibiting electron-lucencies. 3. Rhabdite-forming cells: These cells contain the electron-dense rhabdite granules of up to about 0.3 x 0.9 $\mu$m in size. Rhabdite-forming cells have well-developed cell organelles, granular endolplasmic reticulum, mitochondria and Golgy complex. 4. A-type of basophilic granule cells: These cells contain irregularly-shaped granules exhibiting alcianophilia. These granules surrounded by a limited membrane, approximately 1.4 x 0.7 $\mu$m in size, are accumulated in the cytoplasm. 5. C-type of basophilic granule cells: These cells contain electron-dense granules of less than 0.2 $\mu$m in size, which exhibit PAS- positive reaction. This type of granule is also found in the muscle layer of parenchyma. 6. D-type of basophilic granule cells: This type of granule cell occurs only in the parenchyma around reproductive organ. The granules have cytochemical characteristics that they exhibit strongly positive reaction with PAS and weakly eosinophilic property. These electron-dense granules, which are 0.2 to 0.6 $\mu$m in length, have oval shapes. 7. E-type of basophilic granule cells: These cells are found only in the parenchyma around re productive organ. The granules contained in a small number in the cell, exhibit PAS-positive reaction and have an average size of 0. 2pm. 8. Eosinophilic granule cells: These cells contain a large number of eosinophilic granules which have relatively diverse sizes from 0.3 x 0.2 to 0.8 x 0.4 $\mu$m. Most of granules are round or irregularly-shaped and highly electrondense. These cells have an array of well-developed granular endoplasmic reticulum of which cisternae are distened. 9. Transparent granule cells contain electron-lucent granules which exhibit negative reactions with three kinds of cytochemical methods used in this experiment.

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Analysis on the Microbial Community Structure of Red Granule in the Anaerobic Ammonium Oxidation Reactor (혐기성 암모늄 산화 반응기 내 붉은색 입상슬러지의 미생물 군집구조 분석)

  • Bae, Hyo-Kwan;Park, Kyung-Soon;Chung, Yun-Chul;Jung, Jin-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.10
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    • pp.1055-1064
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    • 2006
  • Extremely slow growing anammox(anaerobic ammonium oxidation) bacteria were cultivated using a combination of UASB(Upflow Anaerobic Sludge Blanket) reactor seeded with anaerobic granular sludge and carbon-fiber cultivating reactor. After 180 days of continuous cultivation, average nitrogen removal rate showed 0.54 kg $N/m^3-day$ when 0.6 kg $N/m^3-day$ of nitrogen loading was applied. The black granule was changed to brown and red granule as continuous operation, and the red granule was highly dependant on the high anammox activity. Microbial community structure of red granule in the UASB reactor was analyzed by molecular methods such as gene cloning, phylogenetic tree analysis, and FISH(Fluorescence In Situ Hybridization) method. As a result of gene cloning and phylogenetic tree analysis, 5 kinds of phylum were found to be Planctomycetes, Proteobacteria, Acidobacteria, Chlorobi and Chloroflexi. 13 clones were matched to anammox bacteria among 51 clones in the red anammox granule. In-silico test which used cloning information and FISH probe of the AMX368 was conducted to detect the presence of anammox bacteria in the red anammox granule. As a result of in-silico test only one clone was exactly matched to AMX368 but 11 clones was mutated one base among 18 bases representing all 12 clones are anammox bacteria. A filamentous Chloroflexi might be related to the granulation of anammox bacteria. As a result of FISH analysis, anammox bacteria was abundant in the red anammox granule.

Ultrastructural Study on Development of the Superior Cervical Ganglion of Human Fetuses (인태아 상경신경절 발육에 관한 전자현미경적 연구)

  • Kim, Dae-Young;Kim, Baik-Yoon;Yoon, Jae-Rhyong
    • Applied Microscopy
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    • v.28 no.2
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    • pp.139-158
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    • 1998
  • The development of the superior cervical ganglion was studied by electron microscopic method in human fetuses ranging from 40 mm to 260 mm of crown-rump length (10 to 30 weeks of gestational age). At 40 mm fetus, the superior cervical ganglion was composed of clusters of undifferentiated cell, primitive neuroblast, primitive supporting cell, and unmyelinated fibers. At 70mm fetus, the neuroblasts and their processes were ensheated by the bodies or processes of satellite cells. The cytoplasm of the neuroblast contained rough endoplasmic reticulum, mitochondria, Golgi complex, Nissl bodies and dense-cored vesicles. As the neuroblasts grew and differentiated dense-cored vesicles moved away from perikaryal cytoplasm into developing processes. Synaptic contacts between the cholinergic axon and dendrites of postganglionic neuron and a few axosomatic synapses were first observed at 70 mm fetus. At 90 mm fetus the superior cervical ganglion consisted of neuroblasts, satellite cells, granule-containing cells, and unmyelinated nerve fibers. The ganglion cells increased somewhat in numbers and size by 150 mm fetus. Further differentiation resulted in the formation of young ganglion cells, whose cytoplasm was densely filled with cell organelles. During next prenatal stage up to 260 mm fetus, the cytoplasm of the ganglion cells contained except for large pigment granules, all intracytoplasmic structures which were also found in mature superior cervical ganglion. A great number of synaptic contact zones between the cholinergic preganglionic axon and the dendrites of the postganglionic neuron were observed and a few axosomatic synapses were also observed. Two morphological types of the granule-containing cells in the superior cervical ganglion were first identified at 90 mm fetus. Type I granule-containing cell occurred in solitary, whereas type II tended to appeared in clusters near the blood capillaries. Synaptic contacts were first found on the solitary granule-containing cell at 150 mm fetus. Synaptic contacts between the soma of type I granule-containing cells and preganglionic axon termials were observed. In addition, synaptic junctions between the processes of the granule- containing cells and dendrites of postganglionic neuron were also observed from 150 mm fetus onward. In conclusion, superior cervical ganglion cells and granule-containing cells arise from a common undifferentiated cell precursor of neural crest . The granule-containg cells exhibit a local modulatory feedback system in the superior cervical ganglion and nay serve as interneurons between the preganglionic and postganglionic cells.

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The Natural Ingredient Application Method of Cigarette Filter (천연소재 담배 필터 적용 방법)

  • Kim, Min-Kyu;Yeo, Woon-Hyung;Kim, Soo-Ho;Oh, Kyung-Hwan;Jin, Yong-Sook;Hwang, Eui-Il
    • Journal of the Korean Society of Tobacco Science
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    • v.35 no.1
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    • pp.13-19
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    • 2013
  • The natural ingredient has been utilized variety of the food and medicine. The aromatherapy well known prevent disease and healthy promotion using the essential oil derived extracted plants. In this work, natural ingredient include herb granulated for application of tobacco filter. That used by granulation using fluidized bed granulator(top-spray, bottom-spray and tangential-spray) and wet granule method. According to ingredient can used granulating method selectivity. So, we used fluid-bed granulator and wet granule method. Grapefruit extract coated sugar particle using the bottom-spray method and red ginseng granule granulated red ginseng powder using the tangential-spray method in a fluidized bed. Then, these granules applied the tobacco filter after due consideration add amount and operation efficiency. As a result, wet granule was loaded dual filter because that similarity carbon granule. And it was fitted in added 3mg/mm, per tip in the tobacco end part. Another type, fuidized bed granules was filled cavity filter because it has high hardness, sphere shape.

Effect of Polysorbate 80 on the Dissolution of Sulfanilamide and Sulfacetamide Granules (Polysorbate 80이 Sulfanilamide및 Sulfacetamide 과립의 용출에 미치는 영향)

  • 구영순;이정순
    • YAKHAK HOEJI
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    • v.31 no.3
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    • pp.189-196
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    • 1987
  • This study was carried out to investigate the effect of surfactant on the dissolution of relatively hydrophilic drugs, such as sulfanilamide (SF) and sulfacetamide (SFA) granules prepared by wet granulation. The additive incorporated in the granules is starch or microcrystalline cellulose(MCC) as an excipient, PVP as a binder, and polysorbate 80 (P-80) as a surfactant. The dissolution characteristics of SF and SFA granules in distilled water were as follows: The values of T$_{75%}$ were 4.60 and 2.50min, respectively for SF and SFA granules. Incorporation of 0.1% P-80 in SF granule ratarded the dissolution of SF as compared with control, but addition of 0.1% P-80 to SFA granule improved the dissolution of SFA in comparison with control. In SF and SFA granules formulated with either starch or PVP, the release of the drug was increased as compared with control. In SF granule, the dissolution of the drug was further reduced by the inclusion of P-80 in the granule containing starch or PVP. Incorporation of P-80 in SFA granule with starch or PVP affected little on the dissolution of the drug. Addition of a nonswelling excipient, MCC decreased the dissolution rate of SF and SFA granules. as compared with each control. The presence of P-80 in these granules made the dissolution rate slower in comparison with the granules containing only MCC.

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Melanin-dispersing Effect of Vasopressin on Frog Skin Melanocyte (Vasopressin의 멜라닌 확산작용에 대하여)

  • Hong, Seung-Kil
    • The Korean Journal of Physiology
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    • v.7 no.2
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    • pp.59-66
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    • 1973
  • It has been reported that vasopressin disperse the melanophore granule of frog skin. The author used hypophysectomized and adrenergic receptor blockaded animals in order to define the mechanism of vasopressin on the melanopore pigment of frog skin. The Rana niglomaculata which could be found in the Seoul area were used on this experiment. The amount of the following drugs were injected into the lymphatic sac of the frog; vaospressin $(0.05\;{\mu}g/g\;B.W.)$, dibenzylin $(0.05\;{\mu}g/g\;B.W.)$, and propranolol $(0.01\;{\mu}g/g\;B.W.)$. The following results were observed; 1. Vasopressin dispersed the melanin granules of melanocyte of frog skin. 2. The melanin granule dispersion activity of vasopressin was observed on the hypophysectomized frog. 3. The melanin granule dispersion was observed on the adrenergic receptor blockaded frog with dibenzylin or propranolol respectively, especially the later one was found to be more obvious. 4. The melanin granule dispersion was observed on the frog which was injected with vasopressin after alpha-receptor or beta-receptor blockade and the later one was found to be more obvious. 5. The melanin granule dispersion was more effective with the blockade of beta-receptor after the treatment with vasopressin on hypophysectomized frog.

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Ultrastructural Changes in the Ganglion and Granule-Containing Cells in the Heart of Vacor-Induced Diabetic Mongolian Gerbil (Vacor 유발 당뇨 모래쥐의 심장신경절과 과립함유세포의 미세구조)

  • Kang, Jung-Chaee;Yoon, Jae-Rhyong;You, Hong-Seok
    • Applied Microscopy
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    • v.23 no.2
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    • pp.107-123
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    • 1993
  • The ultrastructural changes of the cardiac ganglion and granule-containing cells in the heart of vacor-induced diabetic Mongolian gerbils were studied by electron microscopy. After one month of vacor-induced diabetes the ganglion cells showed increase in numbers of dense bodies and mitochondria compared with the normal cardiac ganglion. Most of the satellite cells were filled with numerous phagosomes containing digested debris. Both electron-dense and lucent types of degenerating axon terminals were observed. The former was characterized by clusters of agranular vesicles and numerous mitochondria. The electron lucent type of degenerating axon terminal contained a few agranular vesicles and swollen mitochondria. Degenerating unmyelinated and myelinated axons contained large numbers of dense bodies, lamellar bodies, and mitochondria. Numerous macrophages containing phagosomes were reveled in the interstitial spaces. Some of the granule-containing cells in the heart showed a variety of degenerative changes and a decreased number of dense-cored vesicles. After three months of vacor-induced diabetes the unmyelinated and myelinated axons showed degenerative changes, whereas no structure changes could be demonstrated in intraatrial ganglion and granule containing cells. The satellite cells containing engulfed debris were observed in the cardiac ganglion cells. These results suggest that the degenerative changes occur in the cardiac ganglion cells of vacor-induced diabetic Mongolian gerbils as well as atrial granule-containing cells.

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