• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.111-122
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• 1985

The present study was performed to observe the ultrastructure of the integument of adult Paragonimus westermani. Dogs experimentally infected with 60 metacercariae of F. westermani were autopsied 4 months after the infection. Adult p. westermani were extracted from the dogs and the fine structure was studied by means of scanning and transmission electron microscope. The findings are as follows: 1. Scanning electron microscopic findings showed that the spines and the papillae are distributed at whole body surface but the well developed spines or papaillae are shown around the oral sucker and ventral sucker. 2. At the end of the body, excretory pore was found, the shape was irregular. 3. Transmission electron microscopic findings showed that plasma membrane, tegument, basal lamina, connective tissue, circular muscle layer, longitudinal muscle layer. nerve axon and tegumental cell were observed. 4. In higher magnification, plasma membrance and bar-shaped granules were found at the outer surface of the tegument.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.10a
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• pp.34-35
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• 1991

비대칭 다공막은 표피와 다공층으로 되어 있는 것으로 알려져 왔으나 (그림 1-a), 최근에 두 층 사이에 nodule층의 존재가 여러 연구자들에 의하여 알려졌다. (그림 1-b). 그런데 표피층은 겔화에 의해 그리고 다공층은 binodal에 의한 nucleation and growth 기구로 생성된다는 것이 일반화된 이론이나, nodule 층의 생성에 대한 연구는 없었다. Nodule층의 생성기구를 밝히기 위해서 고분자용액을 편의상 세개의 층으로 나누었으며 (그림 2), 알려진 생성 기구에 의하면 첫째 층은 표피 그리고 셋째는 다공층으로 된다. 그런데 둘째층은 상분리 순간의 고분자 농도에 따라 nodule층 혹은 다공층이 되며, 만일 이 순간의 고분자농도가 임계농도 보다 낮으면 nodule층 그리고 높으면 다공층이 생성된다는 새로운 비대칭 다공막의 생성기구를 제안하였다. (그림 3).

• The Korean Journal of Zoology
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• v.35 no.3
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• pp.362-371
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• 1992

Spiromeiru erinocer익 유충(sparganum)을 전이숙주(paratenic host)인 흰쥐와 종숙주인 고양이에 감염시켜 발육단계에 따라 회수해서 유충과 성충조직의 LDH(lactate dehydrogenase)와 SDH(succinate dehydrogenase)의 분포상 및 동위효소 유형을 효소조직화학적 방법과 전기영동법으로 조사하였다. 첫째, 유충조직에서의 LDH분포는 발육과정에 따른 차이는 없었으며 표피층과 실질근층에 비해 표피근층이 많이 분포하였다. 성체조직에서도 표피근층에 많이 분포하였는데 특히 성체의 표피층에서의 LOH 활성은 수태편절에서 상당히 많은 활성을 보인 반면 다른 편절의 표피층에서는 LDH의 활성이 없었다. 둘째, SDH의 조직분포는 유충과 성충 모두 표피근층에 많이 분포하58h으며 유충에서의 발육 후기는 발육초기보다 SDH의 분포량이 증가하였다. 셋째, LDH등위효소 유형은 유충과 성충에서 2개씩 나타났는데 유충에서는 M.W. 140 Kd가, 성충에서는 56 Kd가 주분획(major band)이었다. 넷째, SDH등위효소는 유충에서 1개(132 Kd), 성충에서 2개(132 Kd, 45 Kd)가'분리되었으며 성충에서 활성이 높게 나타난 band는 45 Kd인 단백질이었다.

• Korean Journal of Plant Tissue Culture
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• v.22 no.3
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• pp.169-173
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• 1995

Border cells are differentiated cells which originate from meristematic cells in The root cap. Experimentally border cells can be released from the root cap by a physical treatment, for example dipping the root tip in the waters After 20-25 hours of release, the new border cell layer forms in the root cap. During the border cell differentiation, new gene expressions were observed in the root cap of pea which was determined by mRNA differential display These new gene expressions may be involved in the border cell differentiation Border cells had unique gene expressions which were determined by mRNA differential display, This suggests that border cells are differentiated cells which are different from the other tissues (ie., leaves, stems, roots or root caps).

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.165-172
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• 1995

A transmission electron microscopic study was performed on the ultrastructure of the tegumental layer of GymophoLloines seoi (Digenea: Gymnophallidae) metacercarlae and adults. The metacercariae were obtained from naturally infected oysters, Crcssosoea gigas, and the adults from experimentally infected C3H mice. The tegumental layer generally revealed a small number of foldings, numerous small vacuoles, sines, and muscle bundles. Beneath the muscle layer, nuclei of the tegumental cells were located. There was little difference in the structure of the tegument between the metacercariae and adults. The oral sucker, having well-developed muscle layers, showed a similar structure to the ventral sucker except numerous foldlngs in the ventral sucker. The ventral pit was surrounded by a thin spcpiu layer, where a number of microtubules and mitochondria were seen. Around the ventral pit located well-developed circular and longitudinal muscles. The results showed that the ultrastructure of the tegumental layer of G. seoi metacercariae and adults revealed little difference from other trematodes in general. The ventral pit, a peculiar structure of this trematode, seems to function as a sphincter or an accessory adhesive organ.

• Journal of Plant Biology
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• v.37 no.4
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• pp.429-434
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• 1994

식물 호르몬의 하나인 앱시스산이 식물의 기공을 닫게 하는 과정 중에 phospholipase C가 활성화되어 inositol 1,4,5-trisphosphate(P3)의 양이 증가함이 보고되었다 (Cot and Crain. 1994). 그러나 아직까지 공변세포에서 phospholipase C의 활성을 조절하는 G-단백질에 대한 보고는 없었다. 그러므로 앱시스산에 의한 기공닫힘과정에 G-단백질이 수반되는지를 조사하고자, G-단백질 활성의 저해제인 pertussis toxin과 촉진제인 cholera toxin을 처리하여 보았다. 닭의장풀(Commelina communis L.)의 잎 뒷면으로부터 얻은 온전한 표피층과 잠두(Vicia faba L)의 잎을 부분 분해하여 공변세포만을 남긴 표피층에 pertussis toxin을 처리하였을 때, 앱시스산에 의한 기공닫힘이 부분적으로 억제됨을 관찰하였다. 그러나 cholera toxin의 경우는 아무런 영향이 없었다. 공변세포만을 지닌 표피층에 pertussis toxin을 전처리한 후 앱시스산을 가했을 때, 앱시스산에 의한 IP3 양의 증가 양상이 억제됨을 확인하였다. 이러한 결과들로부터 앱시스산에 의한 기공닫힘과정에는 pertussis toxin-sensitive, phospholipase C-linked G-protein이 관여하고 있음을 알 수 있었다.

• Composites Research
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• v.17 no.5
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• pp.15-24
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• 2004

Longitudinal strains (${\varepsilon}_x$) of the core and skin layers in glass fiber reinforced plastic (GFRP) cross-ply composite laminates have been measured using the embedded optical fiber sensor of absolute extrinsic Fabry-Perot interferometer (A-EFPI). Transmission optical microscopy was used to investigate the damage behavior around the A-EFPI sensor. Foil-type strain gauges bonded on both the upper and lower surfaces were used for the measurement of the surface strains. It was shown that values of ${\varepsilon}_x$ in the interior of the skin layer and the core layer measured by embedded A-EFPI sensor were significantly higher than that of the specimen surface measured by strain gauges. The experimental results agreed well with those from finite element analysis on the basis of uniform stress model. Large strains in the core layer led to the occurrence of many transverse cracks which drastically reduced the strain at failure of optical fiber sensor embedded in the core layer.

• Korean Journal of Ichthyology
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• v.19 no.2
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• pp.120-127
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• 2007

To investigate the skin of the flat-headed goby, Luciogobius guttatus, it was used 8 body regions such as the head, the upper and lower jaw, the chin, the back, lateral region, abdomen, and the operculum. The epidermis consisted of three layers: the outermost layer, middle layer and stratum germinativum (basal layer). The outermost layer consisted of rather flattened cells arranged in 1 to 4 layers and mucous cells. The middle layer consisted of large epidermal cells occupying the height of the epidermis with 1 to 10 layers, causing a web-shaped structure. Due to the large epidermal cells of the middle layer, L. guttaus had a thick epidermis. The large epidermal cell contains tonofilaments, lucent contents, and desmosome. The basal layer was comprised of a single layer having cuboidal cells. A large number of fine blood capillaries were found just under the basal layer. The dermis consisted mostly of stratum compactum with numerous blood capillaries but had no scale.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.64-65
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• 1994

근래 환경 문제의 중요성이 크게 대두되면서 여러 제조 공정에서 방출되는 폐수등을 처리하는데 필요한 내구성이나, 내미생물성, 내약품성이 우수한 분리막 재료에 대한 연구가 진행되고 있다. 내구성이 우수한 역삼투막 재료를 얻기 위한 방법의 하나로 엔지니어링 플라스틱을 친수화시키는 방법이 개발되어 왔다. 특히 PPO (poly(2-6-dimethyl-1,4-phenylene oxide))로 만들어진 분리막은 내산화성이 우수하고 내구성이 뛰어나다고 알려져왔고 본 연구에서는 PPO에 carboxyl기를 도입하여 친수성을 부여하고, 상전이법을 이용하여 얇은 표피층이 선택성을 높이고 다공성 구조가 표피층을 지지하도록 만든 비대칭성 구조의 분리막을 제조하고 그 투과특성을 살펴보았다.

• Korean Journal of Ichthyology
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• v.20 no.2
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• pp.90-96
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• 2008

The histological morphology on the skin of Misgurnus anguillicaudatus was described in the three regions such as dorsal, lateral, occiput and subsequently morphological variations of the skin were monthly observed for a year. The skin consisted of epidermis having epithelial cell, club cell and mucus cell, and dermis of mainly connective tissue fiber, embedded scale and blood capillary. Unicellular mucus cells situated at the epidermis underwent seasonal change in its size, as well as number and amounts of mucus-secreting materials, which they greatly increased in winter, but did not in summer. As it is getting cold, the mucus cells' shape changed from initial spherical to oval or elongated form. Such considerable changes in the mucus cell were particularly most evident in the occiput during winter. Moreover, the dermis largely thickened about 2~3 times in winter than in summer. Based on these results, we discussed function for the mucus on what it mainly acts in nature and information on whether mucus cells' seasonal variations affect on hibernation and cutaneous respiration.