• Applied Microscopy
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• 제30권3호
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• pp.265-272
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• 2000

낙지 Octopus minor의 상완 신경절을 광학현미경과 전자현미경을 통해 관찰한 결과 다음과 같은 결론을 얻었다. 낙지의 상완신경절은 각각의 흡반 밑에서 둥근 형태로 관찰되었는데 그들의 크기는 흡반의 크기에 비례하였다. 둥근 형태의 상완신경절은 피질부와 수질부 두 부분으로 구분되었던 바, 피질부에서는 신경세포의 집단이, 수질부에는 신경망이 위치해 있었다. 신경세포의 집단에서는 3종류(소, 중, 대형)의 신경세포들이 관찰되었는데 소신경세포는 직경이 $0.9{\mu}m$정도인 둥근 형태의 작은 세포인데 비해 중신경세포는 직경 $1.6\times1.3{\mu}m$정도인 타원형세포였다. 대신경세포는 직경이 $2.8{\mu}m$정도 크기의 난원형의 큰 세포로 확인되었고 이들 3종류의 세포들은 모두 전자밀도가 낮아서 밝게 관찰되었으며 세포소기관의 발달은 미진하였다. 또한 중신경세포인 경우에는 $0.6\times0.4{\mu}m$정도 크기의 전자밀도가 중등도인 방추형 신경교세포에 의해 둘러싸여 있었다. 수질부의 신경망에서는 다양한 크기의 수상돌기와 축색돌기들이 복잡한 그물형태를 하고 있었다. 이들은 돌기내에서 4종류의 화학연접소포 (chemical synaptic vesicle)들을 소지하고 있었는데, 전자밀도가 매우 높고 직경이 100 nm 정도인 electron-dense synaptic vesicle과 전자밀도가 중등도이며 직경이 90nm 정도인 median electron-dense synaptic vesicle 그리고 중앙에 전자밀도가 높은 둥근 핵을 포함하는 직경 90nm정도의 electron-dense cored synaptic vesicle등이 관찰되었다. 그러나 전자밀도가 투명한 연접소포(electron-lucent synaptic vesicle)는 직경이 50nm정도로 가장 작은 형태를 하고 있었다.

• 한국발생생물학회지:발생과생식
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• 제20권4호
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• pp.359-365
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• 2016

Intact germinal vesicle (GV) arrest and release are essential for maintaining the fertility of mammals inducing human. Intact germinal vesicle release, maturation of oocytes is maintained by very complex procedures along with folliculogenesis and is a critical step for embryonic development. Cyclic guanosine monophosphate (cGMP) has been suggested a key factor for meiotic arrest but so far its mechanisms are controversy. In this study we examine the effects of cGMP on germinal vesicle breakdown in cumulus-enclosed oocytes and denuded oocytes. Spontaneous maturation was inhibited by a cGMP agonist, 8-Br-cGMP with concentration dependent manners both in cumulus-enclosed oocytes and denuded oocytes. The inhibitory effect was more severe in denuded oocytes than cumulus-enclosed oocytes. The Rp-8-Br-cGMP and Rp-pCPT-8-Br-cGMP did not severely block GVB compared to 8-Br-cGMP. The spontaneous GVB inhibitory effects were different by the existence of cumulus. Based on them it is suggested that the cumulus modulates the role of cGMP in GV arrest.

• 한국해양바이오학회지
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• 제2권2호
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• pp.123-125
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• 2007

Vibrio anguillarum is a gram-negative bacterium that causes vibriosis in approximately 80 different fish species. V. anguillarum produces several exotoxins are correlated with the pathogenesis of vibriosis. This study is focused on the composition of the outer membrane vesicle. Most of gram-negative bacteria produce outer membrane vesicle (OMV) during cell growth. OMV was formed from the outer membrane surface of cell and than released to extracellular environment. OMV consists of outer membrane lipids, outer membrane protein (OMP), LPS, and soluble periplasmic components. Also, they contain toxins, adhesions, and immunomodulatory. Many gram-negative bacteria were studied out forming OMV. In Vibrio sp., formation of OMV by electron microscopy has been reported from V. cholerae and V. parahaemolyticus. In present study, we isolated OMV from V. anguillarum and OMV protein was separated by SDS-PAGE. Magor band was sliced and analyzed by MALDI-TOF. The major protein band of 38kDa was identified as OmpU by MALDI-TOF MS analysis.

• Clinical and Experimental Reproductive Medicine
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• 제1권1호
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• pp.49-54
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• 1974

In the present studies, effect of progesterone on the germinal vesicle break-down of the mouse oocytes cultured in the micro tube was investigated. The results obtained are as follows: As dose of progesterone in the medium rose, accordingly the break-down of the germinal vesicle was suppressed. It was found that $ED_{50}$ was 15.7 ${\mu}g$/ml, and $ED_{90}$ 60.7 ${\mu}g$/ml of progesterone. The dose suppressing the oocyte maturation was apparently higher than that on the rabbit or on the mouse embryonal development. The inhibiting effect of progesterone on the GVBD was reversible. The germinal vesicle of the oocytes were broken down immediately in the medium upon removal of the hormone. Progesterone stops meiosis at any stage upon administration, while dbe AMP or theophylline supresses only the break-down of the nuclear membrane. Recovering of the meiotic division of the oocytes once exposed to progesterone was delayed a little. The inhibiting action of progesterone was not altered by adding more pyruvate or in the presence of higher concentration of the mineral ions in the culture medium.

• 미생물학회지
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• 제26권1호
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• pp.27-31
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• 1988

Biosynthesis and processing of cytoplasmic mRNA from heterogenous nuclear RNA (hn-RNA) in Aspergillus phoenicis were studied by $^{3}H$-uridine labeling and synchronous culture techniques during their life cycle. Incorporations of $^{3}H$-uridine into hn-RNA and mRNA were most rapid in vesicle-phialide fromation stage and diminished in hyphal growth stage. The processing of cytoplasmic mRNA from hn-RNA was proceeded more rapidly in hyphal growth and conidiophore formation stages than in conidia and vesicle-phialide formation stages. The specific radioactivities of hn-RNA and mRNA were very high in vesicle-phialide formation stage.

• Bulletin of the Korean Chemical Society
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• 제11권6호
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• pp.534-538
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• 1990

Glucagon was found to interact with DMPC vesicles electrostatically and hydrophobically. It appears that glucagon bound irreversibly to the vesicles through hydrophobic interaction was partially protected from the proteolysis by trypsin. Out of three possible sites, only the peptide bond preceded by Arg-18 was cleaved by a prolonged trypsin treatment. ${\alpha}$-chymotrysin did not affect the vesicle-bound glucagon. Based on these observations, possible structure of irreversibly bound glucagon on the vesicle surface is discussed.

• 공업화학
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• 제9권5호
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• pp.763-767
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• 1998

콜레스테롤을 갖는 계면활성제를 합성하고, 이 계면활성제를 단량체[tetradeca(ethylene glycol) diacrylate]와 함께 물 속에서 음파 파쇄하여 vesicle 용액을 형성한 다음, 이 용액내의 물을 증발시켜, 분자들이 규칙적으로 배열된 분자 다층 구조를 갖는 막을 합성하였다. 이 막에 들어 있는 단량체들을 광중합하여, 고분자가 계면활성제들의 층과 층 사이에 들어 있는 분자 다층 구조를 합성하였다. 중합이 끝난 후 유기 용매를 사용하여 계면활성제를 추출하여 이차원적인 구조를 갖는 얇은 박막 층으로 이루어진 고분자 막을 합성하였다. 형성된 이차원 구조를 갖는 고분자 막의 물성을 측정하였는데, 막의 물성으로는 인장 강도, 신장율, 팽윤 등을 측정하였다.

• 대한화학회지
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• 제42권6호
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• pp.708-712
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• 1998

• 한국패류학회지
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• 제27권3호
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• pp.273-282
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• 2011

The ultrastructural characteristics of germ cells during spermatogenesis and mature sperm morphology in male Pinctada martensii were investigated by transmission electron microscope observation. The morphologies of the sperm nucleus and the acrosome of this species are the oval shape and cone shape, respectively. Spermatozoa are approximately $47-50{\mu}m$ in length including a sperm nucleus (about $1.24{\mu}m$ in length), an acrosome (about $0.60{\mu}m$ in length), and tail flagellum (about $45-47{\mu}m$). The axoneme of the sperm tail shows a 9+2 structure. In P. martensii in Pteriidae, a special substructure showing a thick and wide triangular shape which is composed of electron-dense opaque material (occupied about 50% of all, the upper part of the acrosomal vesicle), appeared in the upper region (part) of the acrosomal vesicle, while the lower region (part) of the acrosomal vesicle is composed of electron-lucent material. Thus, this special structure, which exist in the upper part of the acrosomal vesicle in P. martensii, is somewhat different from those of other subacrosomal vesicle in other families in subacrosomal vesicles. Therefore, we assume that the existence of a special substructure showing a thick and wide triangular shape in the acrosomal vesicle of the spermatozoon can be used as a key characteristic for identification of P. martensii or other species in Pteriidae in subclass Pteriomorphia. The number of mitochondria in the midpiece of the sperm of this species are five (exceptionally sometimes four), as one of common characteristics appear the same number of mitochondria in the same families of superfamilyies. This species in Pteriidae does not contain the axial rod and satellite fibres which appear in the species in Ostreidae in subclass Pteriomorphia. These characteristics can be used for the taxonomic analysis of the family or superfamily levels as a systematic key or tools.

• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3509-3513
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• 2014

Phospholipase D (PLD) catalyzed the generation of phosphatidic acid (PA) from phosphatidylcholine (PC) at the outer layer of the vesicles prepared through layer by layer via a double emulsion technique. The generation induced a curvature change in the vesicles, which eventually led them to fuse each other. The ratio of two-fatty-acid-tail ethanolamine (PE) to one-fatty-acid-tail ethanolamine (PE) was found to acquire the condition where the mixed-phospholipid vesicles were stable identically with pure two-fatty-acid-tail PC. The effect of the outer-layer mixture on the PLD-induced vesicle fusion was investigated using the fluorescence intensity change. 8-Aminonaph-thalene-1,3,6-trisulfonic acid disodium salt (ANTS) and p-Xylene-bis(N-pyridinium bromide) (DPX) were encapsulated in the vesicles, respectively, for the quantification of the fusion. The fluorescence scale was calibrated with the fluorescence of a 1/1 mixture of ANTS and DPX vesicles in NaCl buffer taken as 100% fluorescence (0% fusion) and the vesicles containing both ANTS and DPX as 0% fluorescence (100% fusion), considering the leakage into the medium studied directly in a separate experiment using vesicles containing both ANTS and DPX. The fusion data for each composition were acquired with the subtraction of the leakage from the quenching. From the monitoring, the vesicle fusion caused by the PLD reaction seems dominantly to occur rather than the vesicle lysis, because the composition effect on the fusion was observed identically with that on the change in the vesicle structure. Furthermore, the diameter measurements also support the fusion dominancy.