• 대한관절경학회:학술대회논문집
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• 대한관절경학회 2006년도 제15차 추계학술대회 심포지움
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• pp.80-81
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• 2006

• The Korean Journal of Physiology and Pharmacology
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• 제26권6호
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• pp.427-438
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• 2022

Pyroptosis, a form of cell death associated with inflammation, is known to be involved in diabetic nephropathy (DN), and discoid domain receptor 1 (DDR1), an inflammatory regulatory protein, is reported to be associated with diabetes. However, the mechanism underlying DDR1 regulation and pyroptosis in DN remains unknown. We aimed to investigate the effect of DDR1 on renal tubular epithelial cell pyroptosis and the mechanism underlying DN. In this study, we used high glucose (HG)-treated HK-2 cells and rats with a single intraperitoneal injection of streptozotocin as DN models. Subsequently, the expression of pyroptosis-related proteins (cleaved caspase-1, GSDMD-N, Interleukin-1β [IL-1β], and interleukin-18 [IL-18]), DDR1, phosphorylated NF-κB (p-NF-κB), and NLR family pyrin domain-containing 3 (NLRP3) inflammasomes were determined through Western blotting. IL-1β and IL-18 levels were determined using ELISA. The rate of pyroptosis was assessed by propidium iodide (PI) staining. The results revealed upregulated expression of pyroptosisrelated proteins and increased concentration of IL-1β and IL-18, accompanied by DDR1, p-NF-κB, and NLRP3 upregulation in DN rat kidney tissues and HG-treated HK-2 cells. Moreover, DDR1 knockdown in the background of HG treatment resulted in inhibited expression of pyroptosis-related proteins and attenuation of IL-1β and IL-18 production and PI-positive cell frequency via the NF-κB/NLRP3 pathway in HK-2 cells. However, NLRP3 overexpression reversed the effect of DDR1 knockdown on pyroptosis. In conclusion, we demonstrated that DDR1 may be associated with pyroptosis, and DDR1 knockdown inhibited HG-induced renal tubular epithelial cell pyroptosis. The NF-κB/NLRP3 pathway is probably involved in the underlying mechanism of these findings.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2625-2629
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• 2014

Platelets are anuclear discoid-shaped blood cells with key roles in human body. To understand the mechanisms of their activation process, it is required to have analytical imaging techniques capable of acquiring platelet images under fully hydrated conditions. Herein, for the first time, we demonstrate the capability of synchrotron-based transmission X-ray microscopy (TXM) to study platelets (resting and ADP activated) under hydrated and air-dried conditions. To confirm the biological imaging capability of TXM, fixed platelets were imaged and compared with whole mount electron microscopy (EM) images. TXM provided morphological information with sufficient spatial resolution with simple and quick sample preparation procedure. We also observed temporal changes during the platelet activation, which initially had a discoid shape (0 s), formed pseudopodia (30 s) and generated a network of fibrin (5 min). Our results clearly demonstrate the potential of TXM technique to study fully hydrated biological samples under in situ conditions.

• Ocean and Polar Research
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• 제42권2호
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• pp.133-139
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• 2020

The aim of this study is to examine the physiological characteristics of an agarophyte Agarophyton vermiculophyllum (Ohmi) Gurgel, J.N. Norris et Fredericq in the early life stage of tetrasporophytes (2n) and gametophytes (n) to select appropriate seedlings for mariculture. Growth experiments were carried out at the combinations of four temperatures (20, 25, 30, and 35℃) and three light intensity levels (20, 60, and 100 µmol photons m^-2 s^-1) in the two ontogenetic stages: discoid holdfasts and erect sporelings. Holdfast areas and sporeling lengths of tetrasporophytes and gametophytes were estimated after 14 days in culture. Relative growth rates (RGRs) for holdfast areas were 7.08-28.38% day^-1 for tetrasporophytes and 11.58-23.67% day^-1 for gametophytes. At 35℃, holdfasts of tetrasporophytes survived with RGRs of 7.08-23.28% day^-1 but those of gametophytes died. Maximal holdfast growth of tetrasporophytes occurred at 30℃ and 100 µmol photons m^-2 s^-1, which were different from gametophytes (25℃ and 100 µmol photons m^-2 s^-1). RGRs of tetrasporophytic sporelings were 2.93-11.11% day-1 and were between 0.78-10.82% day-1 for gametophytes. Maximal growth of A. vermiculophyllum sporelings occurred at 25℃ and 60 µmol photons m^-2 s^-1 for tetrasporophytes, and at 20℃ and 100 µmol photons m^-2 s^-1 for gametophytes. In conclusion, the present results indicate that carpospores could be used as resources of spore-seedling methods having genetic diversity for mass field cultivation because tetrasporophytes showed higher-temperature tolerance and faster-growing ability than gametophytes of A. vermiculophyllum in the discoid holdfast and sporeling stages.

• 대한관절경학회지
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• 제7권2호
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• pp.153-159
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• 2003

목적 : 내측 및 외측 반월상연골의 전위된 양동이 손잡이형 파열의 양상과 동반손상에 따른 치료원칙과 결과를 비교하고자 하였다. 대상 및 방법 : 1998년 9월부터 2002년 12월까지 본원에서 내측 반월상 연골의 전위된 양동이 손잡이형 파열(이하 I군)로 진단받은 52명 52예와 외측 반월상 연골의 전위된 양동이 손잡이형 파열(이하 II군)로 진단받은 31명 32예를 대상으로 하였으며, 평균연령은 I군 25세($16\~66$세), II군 29세($18\~63$세)였고, 평균 추시기간은 I군 18개월 ($12\~50$개월), II군 13개월($6\~46$개월)이었다. 술중 관절경 검사를 통하여 연골 파열의 부위, 동반손상 여부를 확인하였으며, 외측의 경우 추가적으로 원판형 연골인 경우를 조사하였다 술 후 최종 추시 시 이학적 검사와 임상양상에 따라 치료 판정을 하였으며, 두 군 전체에서 전방십자인대 파열이 동반되었던 경우 추시 관절경을 19례$(23\%)$에서 시행하였다. 결과 : 전방십자인대 파열이 동반된 경우는 I군 38예$(73\%)$, II군 5예$(16\%)$였으며, 원판형 연골이었던 경우는 II군에서 19예$(59\%)$였다. 최종 추시 시 봉합술을 시행한 예에서 I군의 경우 26예 중 22예$(85\%)$는 성공 판정을 받았으며, II군의 경우 3예 중 2예$(67\%)$에서 성공 판정을 받았고, 절제술을 시행한 예에서는 I군의 경우 26예 중 전예에서 II군의 경우 28예 중 26예$(93\%)$에서 성공 판정을 받았다. 이중 I군에서 재수술을 시행한 경우가 봉합술을 시행한 2예에서 있었고, 재수술 당시 1예에서는 봉합부위의 재파열과 다른 1예에서는 새로운 부위의 파열을 발견하였다. II군에서는 원판형 연골의 모양을 보였던 19예 중 2예에서 절제술 후 남아있는 연골에서 새로운 파열이 발견되었다. 결론 : 내측과 외측 반월상연골의 전위된 양동이 손잡이형 파열에 있어 동반 손상이 현저히 다르며, 그 차이를 고려하는 것이 적절한 치료 원칙을 정하는데 도움이 되리라 사료된다.

• ALGAE
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• 제29권3호
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• pp.183-195
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• 2014

There are recognized three new species of Polysiphonia sensu lato at a 10-20 m water depth from Jeju Island, Korea. We described the morphology of three new species and analyzed rbcL sequences to infer phylogenetic relationships among Polysiphonia sensu lato. Polysiphonia amplacapilli sp. nov. is characterized by an epiphytic, discoid holdfast, 5-7 pericentral cells, large trichoblasts, lateral branches connecting with trichoblasts, only slightly corticated in the basal parts, cut-off rhizoids and a spiral arrangement of tetrasporangia. Polysiphonia morroides sp. nov. is characterized by saxicolous, cut-off rhizoids, four pericentral cells, ecorticate, spiral arrangement of tetrasporangia, and it was collected at the fast-flowing water habitat in 20-25 m depth. Polysiphonia sabulosia sp. nov. is characterized by ecorticate, 5-6 pericentral cells, a single filamentous trichoblast, lateral branches connecting with the trichoblasts, cut-off rhizoids, and spiral arrangement of tetrasporangia, and is growing in the sandy locations. The phylogenetic analysis of rbcL sequences demonstrated that three new species are clearly distinguished from other species of Polysiphonia sensu lato.

• ALGAE
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• 제28권3호
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• pp.233-240
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• 2013

Despite specimens' large size and ease of collection in northeast Asian waters, the species diversity of the genus Grateloupia still needs more research in Korea. We investigated plastid rbcL sequences and carried out detailed morphological observation on flattened halymeniacean red alga collected in twelve locations around Korea and Japan. We describe Grateloupia jejuensis sp. nov. based on the distinct clade with high support in our rbcL tree. Grateloupia jejuensis is characterized by solitary or caespitose habit and flattened thalli with discoid holdfast, cartilaginous texture, and blunt or bifid axis. Grateloupia jejuensis was distantly related to G. elata and G. cornea, which have been morphologically confused with the former, and it formed a sister relationship with Prionitis filiformis from California, USA in the rbcL tree.

• Applied Microscopy
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• 제13권1호
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• pp.41-47
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• 1983

A Scanning electron microscope which can obtain additional information not readily available with either the light or transmission electron microscope was used to study the mast cell shape and its granules in normal mammal tissue(rat mesentery, stomach and mouse stomach) by fretting cut using liquid nitrogen. The results showed that rat mesentery and mouse stomach mast cell surfaces had no ridges and microvilli, but revealed several microvilli projecting into the surrounding connective tissue in the rat stomach mast cell. The shape of the mast cell varied from discoid(in the rat mesenteric mast cell) to ellipsoid (rat and mouse stomach), ranging from 7.5 to $10{\mu}m$ in diameter. The shape of the nucleus was ellipsoid and nucleic membrane was adherent to the outer surface of the granules. The granules, approximately 0.2 to $0.9{\mu}m$ in diameter, were various shapes. Frequently, rounded protrusions of cytoplasmic granules could be discerned under the cell membrane. Many small granules were seen in the cytoplasm.

• Applied Microscopy
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• 제28권2호
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• pp.159-170
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• 1998

The glandular secretory system of the capitate gandular trichomes in leaf of Thymus quinquecostatus Celakovsky was examined by transmission electron microscope. The glandular trichome was consisted of three cell layers; an basal cell layer, a stalk cell with single-celled intermediate layer and a discoid secretory layer with thickened cuticle. The secretory cell was dense, rich in mitochondria, rER, plastds, Golgi complex and had many vesicular structure. Typical plastids with reticulate body and plastoglobule were present in glandular trichome. The tytoplasm of secretory cell was filled with osmiophilic secretory materials. The secretory vesicles, originated from Golgi complex, appeared as membrane bounded vesicles and secreted to the outer wall surface. The presences of well developed rER, mitochondria, Golgi complex, and membrane-bounded vesicles fused with plasmalemma in the secreting cells indicate that the granulocrine mechanism of secretion was occurring in T. quinquecostatus. Subcuticular cavity was developed between the cuticular layer and the secretory cell wall, and it formed above the secretory cell upon separation of cuticle-wall.

• ALGAE
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• 제21권2호
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• pp.185-191
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• 2006

The morphology and life history of Stylonema reniforme Kajimura (Stylonematales, Rhodophyta) from Japan were investigated and its taxonomic placement was discussed. This species has 6-30 discoid chloroplasts devoid of a pyrenoid in each cell. This is a typical feature of the genus Goniotrichopsis. The species reproduced only by monospores, which were formed by the direct transformation of the vegetative cells similar to the type species Goniotrichopsis sublittoralis Smith. Goniotrichopsis reniformis (Kajimura) Kikuchi comb. nov. was proposed. The asexual life history of the present species was completed in 3-10 weeks at $15-20^{\circ}C$ in culture.