• Microbiology and Biotechnology Letters
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• v.14 no.4
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• pp.285-291
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• 1986

Immobilized Candida lipolytica cells were prepared by entrapping the whole cells in calcium alginate gel. To enhance citric acid productivity, immobilized cells were Incubated with activation medium in fluidized-bed reactors. When the activation was done in batch operation, maximum citric acid productivity appeared in a much shorter time than in continuous operation. Activated immobilized cells were enhanced about 10-fold in citric acid production relative to non-activated immobilized cells. The productivity of citric acid was also influenced by bead size. When Immobilized cells were reacted in a fluidized-bed reactor with the same quantity of cells, the citric acid productivity was increased as the bead size was decreased.

• The Korean Journal of Zoology
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• v.37 no.2
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• pp.203-212
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• 1994

별불가사리 난자형성 중 난모세포(직경 7-l7O Um) 표면의 구조적 변화를 투과 전자현미경으로 관찰하였다. 직경 25-855 Um의 난모세포에서 'endocvtosis'와 관련된 구조인 coated pit, coated vesicle과 내포소낭이 존재하였으며. 내포소낭은 난황립과 융합하였다. 특히, 이러한 융합은 직경 130-155 Um의 난모세포에서 많이 관찰되었다 난자형성 초기에 난모세포의 미세융모는 세포막을 따라 무질서하게 분포하고. 인접한 세포와 맞닿아 있었다. 직경 15 Um에서 65 Um에 이르는 난모세포는 세포막 부위에 따라서 미세융모의 굵기와 길이, 그리고 형태가 다르게 나타났고, 직경 100 Um 이상의 난모세포에서는 잘 발달된 미세음모가 난뢍층에 존재하였다 여포세포로부터 나온 돌기는 직경 7 Um의 난모세포와 난자형성 후기의 난모세포에서 난황층을 윤고 세포막과 닿아 'junctional complex'를 형성하였다. 이와같은 난모세포 표면의 다양한 구조적 변화는 난모세포의 세포막을 통한 물질투과 기능의 분화와 관련이 있을 것으로 생각된다.

• Applied Microscopy
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• v.32 no.2
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• pp.131-147
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• 2002

Optic lobes of Todarodes pacificus and Octopus minor are largely divided into cortex and medulla, the cortex being composed of three layers (an outer granule cell layer, a plexiform layer, and an inner granule cell layer). The cortex of Todarodes pacificus is about $420{\sim}450{\mu}m$ thick, being $170{\sim}200{\mu}m$ thicker than that of Octopus minor of which thickness is about $250{\sim}290{\mu}m$. In the outer granule cell layer of Todarodes pacificus, three types of nerve cells (type-A, type-B and type-C) and neuroglial cells that surround or contact with the neurons are observed, while in the outer granule cell layer of Octopus minor, two types of nerve cells (type-A and type-B) and a single type of neuroglial cells are observed. In a plexiform layer, a presynaptic bag and nerve endings are connected to each other, consequently forming various types of synaptosomes. The synaptosomes of Todarodes pacificus contain electron dense vesicles, electron dense-core vesicles and electron lucent vesicles, either individually or in a mixture. On the other hand, three types of synaptosomes a mixture of electron dense-core vesicles and electron lucent vesicles, electron lucent vesicles only, and electron dense-core vesicles only are observed in Octopus minor. The structures of the inner granule cell layer are almost similar in the two species. It is composed of two types of nerve cells (type-A, type-B) and a single type of neuroglial cells. In the medulla of Todarodes pacificus, the cells of $7{\times}5{\mu}m$ are arranged to a line and form the palisade cell layer, but these are not observed in Octopus minor.

• Applied Microscopy
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• v.33 no.2
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• pp.117-130
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• 2003

This research investigates the fine structural as well as the morphological changes of the mouse ovarian tissue after irradiation of various dose rates of 6 MeV LINAC radiation. The normal structure of the ovarian tissue is consisted of various stages of follicles including primordial and growing follicles, and ovarian stromal connectives. When we observed the ovarian tissues irradiated with a dose rate of 200 cGy/min using light and electron microscopes, granular cells in growing follicles are in irregular shape unlike normal follicles. Small segments of cells scattered in follicular antrum among granular cells. We could observe neutrophils and macrophages around the segments, which means the cells already got in the process of decease owing to the effects radiation. With coincident to the increase of the dose rate of x-ray irradiation as 400 or 600 cGy/min, the mature follicles appeared as an irregular form and the granular cells surrounding oocyte also deformed comparing to their normal counterparts. The granulosa cells within mature follicle are already occurred necrotic change and apoptosis. The nuclei in some cells got so fragmented that the segments formed the shape of a horseshoe or scattered in small and condensed pieces. All the cells at a granular layer irradiated with a dose rate of 600 cGy/min show typical characteristics of apoptosis. The neutrophils involved in inflammatory reaction appear evidently in follicular antrum of growing follicles, and macrophage scattered with residual and apoptotic bodies.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.4
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• pp.5-11
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• 2004

생체 시스템은 수많은 세포들로 구성되어 있다. 일반적으로 세포막은 단백질과 지방의 혼합체로 구성되어 있으며 두께는 7.5-10nm 정도이다. 단백질은 지방과 함께 세포막을 통한 물질의 이동을 제어하는 역할을 한다. 특히 지방층은 지방에 잘 용해되는 산소나 탄산가스 등은 잘 통과시키지만, 지방에 잘 용해되지 않는 나트륨, 칼륨, 칼슘, 글루코스, 아미노산 등은 지방층 내부에 삽입되어 있는 단백질에 의해 조절된다.(중략)

• Journal of Life Science
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• v.19 no.9
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• pp.1251-1257
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• 2009

We investigated the growth inhibitory effect of internal organs of Todarodes pacificus (TP) on proliferation in human cancer cell lines in vitro. The internal organs of TP were extracted with methanol (TPM), which was then further fractionated into four subfractions by using a solvent partition method, resulting in hexane (TPMH), methanol (TPMM), butanol (TPMB), and aqueous (TPMA) soluble fractions. We determined the cytotoxic effect of these four fractions in three kinds of cancer cell lines - HepG2, MCF-7 and HT-29 - by MTT assay. Among the four subfractions of TPM, TPMH showed the strongest cytotoxic effects at a concentration of $300{\mu}g$/ml, displaying 91.56% on the HepG2 cell line and 85.93% on the MCF-7 cell line. Morphological changes such as membrane shirinking and blebbing of cells were also observed during TPMH treatment of HepG2 cells. In addition, we also observed quinone reductase (QR) induced effect in the methanol (TPMM) layer of HepG2 cells. TPMM showed the highest induction activity of quinone reductase on HepG2 cells among the other partition layers. The QR induced effect of TPMM was determined to be 2.7 at a level of $360{\mu}g$/ml with a control value of 1.0. Although further studies are needed, the present work suggests that internal organs of Todarodes pacificus (TP) may be a chemopreventive agent for the treatment of human cells.

• Journal of Radiation Protection and Research
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• v.32 no.4
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• pp.140-156
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• 2007

This research was performed to investigate the morphological changes of folliculus ovary according to the radiation dose. The whole body radiation of 200 cGy, 400 cGy, and 600 cGy was given to the each groups of 5 months-aged female mouse. Various staining methods used in this research are: Hematosylin-Eosin method, and immunohistochemistrical methods using BrdU, TUNEL, p53, p21, PCNA and inhibin. The minute structural changes of folliculus ovary were observed through an electron microscope with high magnification. The morphological changes of growing folliculus ovary became distinct as the dose of X-rays increased. Especially, the nuclei of granular cells showed manifest condensation and the changes of the transparent zone were distinct. As a result of histochemical reaction according to Masson's trichrome method and reticular fiber method, the changed granular cells, the deformed basilar membrane of folliculus ovary and the abnormal arrangement of the reticular fiber were observed. In the reaction of BrdU, the granular cells of normal folliculus ovary with positive reaction rapidly decreased according to the increase of the dose of X-rays. In TUNEL study, granular cells showing positive reaction in retarded folliculus ovary were expanded to growing folliculus ovary and primordial folliculus ovary according to the increase of the dose of X-rays. In case of 600 cGy of X-rays, oocyte underwent apoptosis. In p53 immunohistochemistry, p53 manifested to be stronger as the dose of X-rays increased. p53 reactivity was manifested distinctively in all cells comprising folliculus ovary following irradiation of 600 cGy. p21 was manifested in granular cells of folliculus ovary and showed very positive reaction around follicular antrum according to the increase of the dose of X-rays. In PCNA, positive reaction was manifested in growing folliculus ovary, mature folliculus ovary and primordial folliculus ovary, but the extent of the reaction decreased as the dose of the X-rays decreased. The finding that the reaction of granular cells around folliculus ovary was stronger than that near follicular membrane indicates that what was damaged first by X-ray was the cells near folliculus ovary and follicular antrum. The reactivity of $inhibin-{\alpha}$ showed difference according to the growing stage of folliculus ovary: $inhibin-{\alpha}$ showed the most strong reaction in mature folliculus ovary with follicular antrum. There was strong reaction in granular cells around follicular membrane but $inhibin-{\alpha}$ did not occur at all in theca cells comprising follicular membrane. $Inhibin-{\alpha}$ in ovary tissue exposed to 400 cGy of X-rays was manifested more strongly than in ovary tissue exposed to 600 cGy of X-rays, which was related to the phenomenon that granular cells of mature folliculus ovary underwent necrosis or apoptosis increasingly due to X-rays. In an electron microscope with high magnification, nuclei and protoplasm of granular cells in growing folliculus ovary abruptly underwent minute structural changes according to the increase of dose of X-rays. Cell residue, by-product of cell decease, neutrophil and macrophage around follicular antrum were observed. The minute structural changes in granular cells showed typical characteristics of apoptosis: the increase of electronic density due to nuclear condensation, fragmentation of nuclei and atrophy of protoplasm. Necrosis of cells was identified but it was not so remarkable. Macrophage with apoptotic bodies was scattered. Proportional to the radiation dose, we found that the generation of heterogeneous substance of normal ovary texture's follicular fluid, the emergence of dyeing characteristic in the basilar membrane of folicle, the generation of apoptosis, and the transformation of macrophages, etc. From this results, we can infer the possible radiation hazard on the ovary of cervix cancer patient with radiation therapy.

• Journal of Food Hygiene and Safety
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• v.16 no.2
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• pp.117-124
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• 2001

The main constituent of green tea, catechins have been reported to have numberous biological anti-vites including antimutagenic, antibacterial, hypocholesterolemic, antioxidant and antitumor properties. In the present study, we examined the protective effect of catechin on UVB-induced skin damage. Catechin (3 mg/mouse) was topically treated to dorsal area of SHK-1 hairless mouse daily for 2 weeks. UVB (100 mJ/$\textrm{cm}^2$) was also treated soon after application of catechin alone or with catechin for 2 weeks. Catechin reduced UVB-induced infiltration of inflammatory cells, fibrosis of cells and collagen-fiber formation. In addition, catechin also prevented UVB-induced DNA fragmentation and apoptosis cell number, but not changed p53 level. Furthermore catechin inhibited UVB-induced cell proliferation. There results showed that catechin have preventive effect aganinst UVB-induced skin damages. and these effects could contribute to the antitumor promoters activity.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.571-584
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• 2004

It is known widely that granulosa cell apoptosis leads follicular atresia and macrophages exert their effects directly and/or indirectly from the initiation to the completion of follicular atresia by phagocytosis of apoptotic bodies and secretion of various cytokines. However, the site of initiation, propagation routes and the elimination methods of apoptotic bodies, and the time and methods of penetration of macrophages into the follicles are not known completely. Using pig(Yorkshire-breed) ovary, immunohistochemical studies with TUNEL for apoptotic bodies and pig macrophage monoclonal antibody 4E9 for macrophages, and light and transmission electron microscopic observations were performed. In the pig, follicular atresia began with the granulosa cell apoptosis, and the apoptosis of theca intema cells occured at the same time. The apoptosis of granulosa cells initiated randomly within the granulosa cell layer and propagated rapidly into the whole layer. Ultrastructura1ly, apoptotic granulosa cells showed characteristic pyknotic and deformed nucleus and intracytoplasmic vesicles. Apoptotic bodies were eliminated by intact granulosa cells and macrophages. Intact granulosa cells ingested apoptotic bodies transiently, soon after they fell into the apoptosis. Finally, apoptotic bodies and degenerated oocyte were phagocytosed by macrophages. Macrophages entered the ovarian follicle at the time of initiation of granulosa cell apoptosis, and migrated with the progression of apoptosis. By elimination of theca cells, macrophages contributed the completion of follicular atresia These results will provide valuable informations on the study of the interrelation between macrophage and ovarian follicular atresia.

• Applied Microscopy
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• v.29 no.4
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• pp.417-426
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• 1999

The present investigation is designed to provide basic information on fine structure of the skin of the sea bass, Lateolabrax japonicks in relation to study of epidermal change with environmental and physiological change. The skin of the sea bass is divided into the epidermal layer and dermal layer. Epidermal layer consists of supporting cells and unicellular glands. The supporting cells were classified into the superficial cell, intermediated cell and basal cell. Gland cells were classified into the mucous secretory cell and club cell which is more frequently observed. Superficial cell of epidermal layer is squamous or cuboidal and contains well-developed rough endoplasmic reticulum and the surface is covered with numerous microridges. Superficial cells are connected to another cell with membrane interdigitations and desmosomes. Intermediated cell is ovoid and the electron density is higher than the other supporting cells. Basal cell is cuboidal and has a well-developed mitochondria and membrane interdigitation. The mucous secretory cell has a numerous membrane bounded secretory granules. The cytoplasm of club cell is divided into cortex and medullar. The medullar cytoplasm has a nucleus, intracellular organelles and central vacuole, and the cortical cytoplasm has a well-developed tonofilament. Club cells are connected to another cell with well -developed membrane interdigitations and desmosomes.