• Animal cells and systems
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• v.3 no.4
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• pp.407-412
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• 1999

The influence of eating habits and food type on the ultrastructural characteristics of the digestive tracts was studied under the scanning and transmission electron microscopes in two crustacean decapods (Hemigrapsus penicillatus De Haan; mud crab, Pinnotheres cyclinus Shen; symbiotic crab). The relative ratio of the length of midgut versus hindgut was 1:1 in the mud crab, but 4:1 in the symbiotic crab. Observation through the scanning electron microscope revealed that the midguts of both species have densely-arranged longitudinal mucosal folds with a smooth surface. In the hindgut of the mud crab, mucosal folds were longitudinally oriented, clusters of two to five spines were observed on the cuticular surface, and the length of the spine in the distal hindgut was longer than that in the proximal portion. In the symbiotic crab, the mucosal folds were irregulary arranged, and numerous rudimentary spinal structures were noted on the cuticular surface. Through observation of a transmission electron microscope, the epithelial cells of the midgut in both species had numerous microvilli, but the length of the microvilli was slightly longer in the mud crab than in the symbiotic crab. The central layer of the basement membrane and the muscular layer of the midgut were more developed in the mud crab than in the symbiotic crab. The thickness of the cuticular layer over the hindgut surface in the mud crab was about 4 times than that of the symbiotic crab.

• Journal of Plant Biology
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• v.38 no.3
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• pp.275-280
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• 1995

The formation of osmiophilic globules related to the granal lysis has been investigated with a shade plant ginseng (Panax ginseng C. A. Meyer) exposed to full sunlight. The changes of chloroplast were examined as a function of time over 9 days under full sunlight exposure. The ultrastructure of ginseng leaf showed swelling of the granal thylakoid during an early stage of the light exposure. The thylakoid membrane faded and small electron-opaque dots were aggregated on the edges of the granal thylakoid membrane when the exposure time was increased over 1 day. Then, the sahpe of the grana changed into round. After the exposure over 3 days, there appeared many osmiophilic globules with multi-lamellated concentric structure. The globules at this stage were partly accumulated with osmiophilic substances. The outermost membrane of these multi-lamellated osmiophilic globules was attached to the stromal thylakoid membrane connecting to the deforming grana. The osmiophilic globules were elongated after 9 days. In this stage, the multi-lamellated structure was difficult to identify due to severe accumulation of osmiophilic substances. The number of the osmiophilic globules also increased along with the full sunlight exposure time. This observation leads us to believe that the multi-lamellated osmiophilic globules came from the deformation of grana.

• Applied Microscopy
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• v.17 no.1
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• pp.29-46
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• 1987

To study hexavalent chromium effects on mitochondrial electron transport, the activities of electron transport enzymes and conformational change of mitochondria treated with $40{\mu}M$ of sodium dichromate ($Na_{2}Cr_{2}O_{7}\;2H_{2}O$) were investigated. And so were those of liver mitochondria isolated from mouse intraperitoneally injected with sodium dichromate, 40mg per kg body weight. On both treatment with chromium(VI), the activities of electron transfer enzymes (Complex I and IV) were increased to some extent and the ultrastructural transformation of mitochondria from a condensed to an orthodox conformation was inhibited under State IV respiration. These results represent' inhibitory effect of hexavalent chromium on electron transport without inhibiting electron transfer enzymes (Complex I and IV) in mitochondria. On intraperitoneal treatment with hexavalent chromium as sodium dichromate and trivalent chromium as chromic chloride, containing 37.5 mg of chromium per kg body weight, respectively, the activities of electron transfer enzymes of liver isolated from mouse with chromium(VI) was reduced, but that with chromium(III) was not affected. And with chromium(VI), all mice after 12 hours of treatment died, only after 6 hours survived. With chromium(III), however, all survived. This indicates that hexavalent chromium is more toxic than trivalent chromiumin mouse liver.

• The Journal of Korean Physical Therapy
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• v.16 no.2
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• pp.63-71
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• 2004

Denervated skeletal muscle produces muscle atrophy as well as changes at the neuromuscular junction which leads to terminal axonal sprouting and an ultrastructural remodeling. NT-3 is expressed in adult muscle and motoneurons. Normally NT-3 has a potential role in regulating adult neuromuscular jungtion and recovering following muscle atrophy. Also, it could influence synaptic neurotransmission between motoneurons and skeletal muscle cells. The purpose of this study was to investigate the effect of electrical stimulation therapy(EST) on NT-3 expression in neuromuscular junction following sciatic nerve transsection in rats. After EST application during 7 days, the immunoreactivity of NT-3 was increased in neuromuscular junction

• Korean Journal of Veterinary Pathology
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• v.3 no.1
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• pp.7-14
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• 1999

We investigated the effect of a single intravenous dose of Fumonisin $B_1(FB_1$) of rat kidney on the time sequence. Male Sprague-Dawley rats were intravenouslyin jected with FB$_1$at 1.25 mg/kg and were euthanized at 12 hrs, 1, 2, 4, and 6 days after the injection. In $FB_1$ treated rats, serum BUN and creatinine were elevated from 12 hrs. Microscopically, the initial target site was tubules of inner stripe, with mild degenerative and necrotic changes at 12 hrs, but the tubules recovered on day 4. In outer stripe, there were only a few scattered necrotic cells on day 1. These changes became more obvious over the time passed and most severe on day 4. On day 6, regeneration occurred, manifest as hypertrophic, basophilic tubular cells. The dying cells were proved to necrotic cells instead of apoptotic cells by TUNEL. Ultrastructural changes were cytoplasmic vacuole, dilated endoplasmic reticulum, swollen mitochondria, ballooned microvilli of the tubular cell in the outer stripe. These results showed that the renal tubules of outer medulla were the target to $FB_1$-induced nephrotoxicity in the rat. However, initial target was mner stnpe of medulla.

• Korean Journal of Veterinary Research
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• v.19 no.1
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• pp.33-44
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• 1979

Herpes virus인 소의 전염성 비기관염 바이러스와 악성 카탈열 바이러스의 형태(形態)와 그 형성과정(形成過程)(형태발생(形態發生))을 조직배양(組織培養)에서 각기 시험(試驗)하였다. 이 두 종류(種類)의 바이러스는 herpes virus의 특징적(特徵的)인 구조(構造)를 가지나 그 형태발생(形態發生)이 상이(相異)함을 밝혔다. 1. 소의 전염성비기관염(傳染性鼻氣管炎) 바이러스 (IBRV/CT3) 배양에서 그 바이러스의 envelope는 세포질막(細胞質膜)으로부터 유래(由來)됨을 밝혔다. 2. IBRV/CT3 배양에서 envelope는 가진 바이러스는 세포핵내(細胞核內)에는 전혀 나타나지 않았다. 3. 소의 악성(惡性)카탈열(熱) 바이러스(MCFV/C500)의 배양에서 그 바이러스의 envelope는 세포핵막(細胞核膜)으로부터 유래(由來)됨을 밝혔다. 4. 소의 악성(惡性)카탈열(熱) 바이러스(MCFV/C500)에 감염(感染)된 토끼의 폐장(肺臟)에서 얻은 macrophage에 대해 바이러스의 소재(所在)를 추구(追究)한바, 이 바이러스는 macrophage의 세포질내(細胞質內)에만 존재(存在)함을 밝혔다. 그리고 이 바이러스는 탐식(貪食)된 바이러스임을 알았다.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.133-142
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• 1996

Ten intrabony defects in 10 patients were treated by flap surgery including root surface debridement and placement of an expanded polytetrafluoroethylene(ePTFE) membrane. The membranes were removed after 4-6 weeks. This study was performed to examine the retrived ePTFE membrane by scanning electron microscopy(SEM) for bacterial contamination and adherent connective tissue elements, and to compare it with clinical conditions. The cervical portion of the membrane, which in most cases had become partially exposed to the oral cavity, had a bacterial deposit. Small bacterial colonies and a scatter of single cells in some instances extended into the apical portion of the membrane. Fibroblast-like cells, erythrocytes and fibrous structures were seen in the apical portion of the membrane. Outer surface of membrane tends to more bacterial contamination than inner surface(p<0.01), and upper portions more than lower portions(P<0.01). Comparison of ultrastructural findings and clinical conditions revealed that extent of bacterial contamination of the membrane correlated with gingival inflammation and extent of membrane exposure, but it was not significant statistically. The results suggested that gingival inflammation and membrane exposure affect periodontal regeneration by the use of ePTFE membrane.

• ALGAE
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• v.21 no.4
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• pp.407-416
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• 2006

Low molecular weight carbohydrates, phycobilin pigments and cell structure using light and transmission electron microscopy were used to describe a new genus of unicellular red algae, Erythrolobus coxiae (Porphyridiales, Porphyrideophyceae, Rhodophyta). The nucleus of Erythrolobus is located at the cell periphery and the pyrenoid, enclosed by a cytoplasmic starch sheath, is in the cell center. The pyrenoid matrix contains branched tubular thylakoids and four or more chloroplast lobes extend from the pyrenoid along the cell periphery. A peripheral encircling thylakoid is absent. The Golgi apparatus faces outward at the cell periphery and is always associated with a mitochondrion. Porphyridium and Flintiella, the other members of the Porphyrideophyceae, also lack a peripheral encircling thylakoid and have an ER-mitochondria-Golgi association. The low molecular weight carbohydrates digeneaside and floridoside are present, unlike both Porphyridium and Flintiella, which have only floridoside. The phycobilin pigments B-phycoerythrin, R-phycocyanin and allophycocyanin are present, similar to Porphyridium purpureum. The cells have a slow gliding motility without changing shape and do not require substrate contact. The ultrastructural features are unique to members of the Porphyrideophyceae and recent molecular analyses clearly establish the validity of this new red algal class and the genus Erythrolobus.

• The Journal of Korean Medicine
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• v.22 no.4
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• pp.79-89
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• 2001

Objectives : This study has been carried out to investigate the effects of the Saengjinyanghyutang-gamibang and Rosa rugosa extracts on pancreas of the hyperglycemia mice induced with streptozotocin. Methods : We examined immunohistochemistry for insulin and COX-2, ultrastructural changes of acini by electron microscope, and changes of the blood glucose and BUN levels. Results : The ${\beta}-cells$ on Langerhnan's islet were destructed by administration of streptozotocin, so that few insulin-positive cells were observed in the control group. However, a lot of insulin-positive cells were observed in the experimental groups. These cells had recovered from the damage. As a result of COX-2 immunostain, COX-2 expression were highest in the control group other than the Saengjinyanghyutang-gamibang and Rosa rugosa extracts administered groups. As the electron microscopical observation, the centroacinar cells and acini of pancreas were destructed or damaged by administration of streptozotocin in the control group, but these recovered !Tom the damage in the other experimental groups. The levels of serum glucose were decreased remarkably on the Rosa rugosa and Saengjinyanghyutang-gamibang extracts administered groups compared with control group. Conclusions : These results suggest that administration of the Rosa rugosa and Saengjinyanghyultang-gamibang extracts to the mice reduced the damage induced by streptozotocin.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.736-752
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• 1995

Fine structural changes of germ cell during the gametogenesis of Korean rockfish, Sebastes schlegeli sampled in west coast of Korea were investigated from September 1993 to August 1994. In a layer of microvilli of oocyte with active yolk duplication, many pinocytotic vesicles containing protein granules regarded as yolk precursors were observed. The multivesicular bodies were formed by gathered mitochondria. They are participated in formation of the primary yolk globules homogeneously filled with high dense particles and enclosed within a limiting membrane. The precursors of yolk globule appeared to be formed by modification of mitochondria and they developed into the primary yolk globules with participation of large and dense pinocytotic vesicles. Yolk globules in mature oocyte were consisted of three components: the crystalline type main body, the superficial layer with dense and fine granules, and the limiting membrane. Steroid hormone secreting cells were recognized in the interstitial cells of growing testis. Numerous endoplasmic reticula and large mitochondria with well developed tubular cristae appeared in their cytoplasms. The axoneme in the tail flagellum of spermatozoon consisted of nine pairs of microtubules at the periphery and one pair at the center, and they were covered with doublet microtubules.