• Title/Summary/Keyword: vesicle

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Two New Eisenia Species from South Korea Similar to E. koreana and Comparable to Eisenoides from USA (Oligochaeta: Lumbricidae)

  • Blakemore, Robert J.;Park, Tae Seo
    • Animal Systematics, Evolution and Diversity
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    • v.28 no.4
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    • pp.297-303
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    • 2012
  • New Korean lumbricids are described: Eisenia gaga Blakemore sp. nov. from remote Gageodo Island and E. sindo Blakemore, sp. nov. from an island at Incheon. Both are comparable to Eisenia koreana (Zicsi, 1972) from near Pyongyang, North Korea. A remarkable yet previously unrecognized similarity to American earthworm Eisenoides carolinensis (Michaelsen, 1910) is discussed, but synonymy is rejected on tenuous morphological grounds (form of nephridial vesicle bladders) with taxonomy supported by objective molecular data (mtDNA cytochrome c oxidase subunit 1 barcodes).

Kinetics of Structural Transitions in Surfactant Solution (계면활성제 수용액에 있어 구조변화에 따른 동력학적 고찰)

  • Nam, Ki-Dae
    • Journal of the Korean Applied Science and Technology
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    • v.18 no.3
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    • pp.161-166
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    • 2001
  • While the equilibrium behaviour of surfactant solution is well studied, the understanding of the kinetics and pathways of structural transition under nonequilibrium conditions is only begining to develop. Attention has recently been directed mainly towards micellar kinectics, transitions between micellar and lamellar phases, vesicle fusion, and phases separation in microemulsions. This progress has profited greatly from developments that have taken place in various techniques and instruments.

$Ca^{2+}$ CALMODULIN CAUSES RAB3A TO DISSOCIATE FROM SYNAPTOSOMAL MEMBRANES

  • Park, Jae-Bong;Christoper C. Farnsworth;John A. Glomset
    • Proceedings of the Korean Biophysical Society Conference
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    • 1996.07a
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    • pp.38-38
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    • 1996
  • Rab3A is a synaptic vesicle-associated, GTP-binding protein that has been implicated in the regulation of neurotransmission. We show here that Ca2+/calmodulin can form a 1:1 complex with Rab3A and cause it to dissociate from synaptosomal membranes. Formation of the complex requires both the lipidated C-terminus of Rab3A and the presence of guanine nucleotide. (omitted)

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Studies on the Nitrogen-fixing Symbiosis in Actinorhizal Plants I. Survey of the actinorhizal root nodules and collection the root nodules (목본식물에 있어서 질소고정 공생관계 (Actinorhizal symbiosis)에 관한 연구)

  • 안정선
    • Journal of Plant Biology
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    • v.29 no.2
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    • pp.109-115
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    • 1986
  • Actinorhizal plants being capable of fixing atmospheric nitrogen in symbiotic association with Frankia were surveyed for their root nodules, and the root nodules were collected for further studies. Three species of Alnus and Elaeagnus (A. hirsuta, a. firma, A. japonica; E. glabra, e. umbellata, E. macrophylla) and one species of Myrica (M. rubura) were confirmed to bear the root nodules of typical external shape. Morphological studies using light microscope and scanning electron microscope revealed the presence of vesicle clusters in the cortex region of the root. Two tentative endophyte colonies were isolated from the root nodule of A. hirsuta.

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Transdermal and topical LMWH delivery from ultradeformable and other vesicles: Characterization and in vitro and vivo permeation studies

  • Hyun, Myung-Ja;Park, Jeong-Sook;Kim, Chong-Kook
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.247.2-247.2
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    • 2003
  • To increase skin permeability of LMWH (Low Molecular Weight Heparin), ultradeformable liposomes were developed. Ultradeformable liposomes were developed by Egg phosphatidylcholine (Egg-PC) and edge activator. Entrapment efficiency, vesicle size and zeta potential of vesicles were determined and characterized for deformability and stability. Transepidermal permeation of LMWH was compared to saturated aqueous control in vitro. The steady-state flux and its maximum time were calculated from the flux curves. (omitted)

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A Study on the Factors Affecting Entrapment Efficiency and Particle Size of Ethosomes (Ethosomes의 포집효율과 입자크기에 영향을 주는 인자에 관한 연구)

  • Jin, Byung Suk;Lee, Sang Mook;Lee, Kwang Hee
    • Applied Chemistry for Engineering
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    • v.17 no.2
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    • pp.138-143
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    • 2006
  • Ethosome is a liquid crystalline vesicle prepared by hydration of ethanol-dissolved lecithin with a solution containing hydrophilic components. Investigation of factors affecting the entrapment efficiency and particle size of ethosomes was carried out, because the high entrapment efficiency and small particle size are prerequisite in developing ethosomes as a drug delivery system. The variations of properties of ethosomes with constituent composition and preparation method were examined using a calcein as a hydrophilic marker. It was observed that the amount of ethanol and calcein solution, phosphatidyl choline content in lecithin, preparation temperature, stirring rate, and PBS addition method had a considerable effect on the properties of ethosome. Sonication treatment resulted in the reduction of entrapment efficiency of ethosome, which was due to the release of entrapped components in the vesicles by strong sonication vibration.

Studies on the Effect of Hypoxanthine on Nuclear Maturation of Mammalian Oocytes (Hyposanthine이 포유동물 난자의 핵성숙에 미치는 영향)

  • 지희준
    • Korean Journal of Animal Reproduction
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    • v.20 no.4
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    • pp.427-432
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    • 1997
  • These studies were performed to approach the precise pathway inducing the meiotic inhibitory action of hypoxanthine on mouse follicular oocytes and to identify the cause of detrimental effect of hypoxanthine on viability of the oocyte in vitro. In addition, a correlation between the meiotic inhibitory effect and the detrimental effect of hypoxanthine was investigated. Mouse follicular oocytes at germinal vesicle(GV) stage were collected from the ovaries of ICR mice by puncturing the antral follicles with a fine needle, at 48 hours after PMSG injection. Oocytes were cultured in Modified Whittingham's T6 media containing hypoxanthine and several materials that involved in metabolism of hypoxanthine, and the effects of the materials on the actions of hypoxanthine were investigated by observing germinal vesicle breake down (GVBD), 1st polar body (PB) extrusion and viability of the oocytes. Phophodiesterase significantly reduced the meiotic inhibitory effect of dbcAMP but did not influence on the inhibitory effect of hypoxanthine. Allopurinol and 6-MP significantly enhanced the meiotic inhibitory effect of hypoxanthine, but the materials themselves also showed the meiotic inhibitory action like hypoxanthine. Hypoxanthine-guanine phosphoribosyltransferase significantly enhanced the meiotic inhibitory effect of hypoxanthine, on the contrary HGPRT itself promoted meiotic resumption of the oocytes. Catalase did not induce any change in the meiotic inhibitory effect of hypoxanthine, but SOD increased the GVBD rate suppressed by hypoxanthine. The detrimental effect of hypoxanthine on viability of the oocytes was significantly reduced by allopurinol and catalase, but SOD increased the GVBD rate suppressed by hypoxanthine. The detrimental effect of hypoxanthine on viability of the oocytes was significantly reduced by allopurinol and catalase, but SOD did not reduce the deterimental effect of hypoxanthine. In conclusion, the meiotic inhibtory effect of hypoxanthine may be caused by guanyl dervartives converted from hypoxanthine via salvage pathway, and superoxide anion may partially participate in the inhibitory effect of hypoxanthine. The detrimental effect of hypoxanthine on viability of the oocytes be cused by hydrogen peroxide produced during the metabolism of hypoxanthine.

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Histochemical and Electron Microscopic Study on the Zinc-containing Neurons in Rat Spinal Cord (흰쥐의 척수에서 아연이 함유된 신경원에 대한 조직화학 및 전자현미경적 연구)

  • Cho, Hyun-Wook;Han, Weon-Dong
    • Applied Microscopy
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    • v.26 no.2
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    • pp.243-252
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    • 1996
  • The somata and boutons of the zinc-containing neurons in the spinal cord of the rats were labeled by intraperitoneal injection of sodium selenite and silver amplification. The labeled somata of the neurons were located in laminae V, VI, VII and X of the gray matter. The zinc selenium reaction products were retrogradely transported and precipitated into somata of the neuron with survival 8 hours. This observation suggest that all or part of the spinal cord zinc-containing neurons are interneurons. At survival 1 hour, the loaded axonal boutons with zinc precipitates of zinc-containing neurons were distributed in the gray matter and in the processes of lateral and ventral funiculi of the white matter. In particular, AMG stained boutons with huge form were appeared in the lamina IX. Ultrastructurally, the zinc precipitates were located in the cytoplasmic lysosomes or the vesicle within boutons of the zinc-containing neuron in accordance with survival times.

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Effects of Adenosine, Guanosine and Azaserine on Maturation of Mouse Oocytes In Vitro (생쥐 미성숙난자의 체외성숙에 미치는 Adenosine, Guanosine 및 Azaserine의 영향)

  • 전용필;김정훈;목정은;김문규
    • Korean Journal of Animal Reproduction
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    • v.21 no.2
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    • pp.123-130
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    • 1997
  • Normal maturation of the mammalian oocytes is prerequisite for the fertilization and the early embryonic development. We have been tested the effects of purine and its de novo synthetic inhibitor, azaserine(Aza) on the maturation of germinal vesicle(GV) and germinal vesicle breakdown(GVBD) mouse oocytes. Denude-immature oocytes were cultivated in the media containing adenosine, guanosine, and/or azaserine, and checked the matruation stage by monitoring the prominent morphological changes. In GV stage oocytes, GV was arrested temporarily by the adenosine(1.0%) and protractedly by the guanosine(65.9%, P<0.001). The regression was increased significantly at the adenosine(90%, P<0.001) but decreased at the guanosine(1.6%, P<0.05). Inhibiting the de novo synthesis of purine, nuclear maturation rate was increase(90.4% : 96.7%), but GV arrest was significantly increased by cotreatment with guanosine(P<0.001). Polar body extraction significantly was increased at the Aza(P<0.05), but not in others. In GVBD oocytes, adenosine itself did not affect GVBD arrest. Guanosine, on the other hand, elevated GVBD arrest rate(P<0.001), but co-treated with Aza, decreased GVBD arrest(P<0.001). Aza increased GVBD arrest rate(20.2%, P<0.05) compared with control. From those results, we know that guanosine shows more prominent effect on the inhibition of nuclear maturation at the GV stage, and of the 1st polar body extrusion at the GVBD stage. Adenosine showed the cytoplasmic toxicity at GV stage oocyte. Our data speculate that cytoplasmic cAMP level is auto-regulated by endogenous adenylate cyclase while GVBD is inhibited by guanosine, since purine toxicity is not observed in the GVBD stage. And it is showed that purine metabolism is concerned with nuclear maturation, that the amounts of purine metabolism is not even during the oocyte maturation.

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