• Korean Journal of Veterinary Research
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• v.39 no.2
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• pp.359-364
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• 1999

We investigated the pathological changes in young rabbits which were experimentally infected with rabbit hemorrhagic disease virus (RHDV). Experimental infection of RHDV was carried out in both thymectomized and non-thymectomized young immature rabbits and adult rabbits. None of young rabbits infected with RHDV died during the experiment. Histologically, single or focal hepatocellular degeneration and necrosis with mild lymphocyte infiltration were observed in the rabbits killed at 30 hours and 5 days PI. Lymphocyte infiltration was more severe at 5 days PI than at 30 hours PI. RHDV antigens were mainly detected in the degenerating hepatocytes adjacent to the infiltrated lymphocytes at 30 hours PI and 5 days PI. In electron microscopical observation, infiltrated lymphocytes in the lesions had large nuclei without cytoplasmic granules and interdigitated with adjacent hepatocytes. It is assumed that infiltrated lymphocytes in hepatic lesions in RHDV infected young rabbits are T-lymphocytes and originate from peripheral lymphoid organs or tissues rather than from thymus.

• Applied Microscopy
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• v.18 no.1
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• pp.77-91
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• 1988

Since the Urechis unicinctus-oocyte grows asynchronously in the body fluid, various oocytes in developmental stages can be prepared from each individual. The oocytes obtained from the coelomic fluid are then classified into five developmental stages according to the fine structural features. The earlier oocytes (${\sim}18{\mu}m$) form cluster and thereafter the oocytes grow singly without a distinct support of somatic cell, such as accessory cell or matrix cell. The yolk granules begin to appear already in the oocyte of cluster stage, however, the typical yolk was observed at the stage IV. Therefore, it was suggested that the yolk deposition is correlated with the coelomic fluid. The mature oocyte measured about $150{\mu}m$ produces the invagination not only on oolemma(indentation) but also on nuclear envelope. After the formation of the indentation, the mature ooytes are stored in storge sacs. The fine structural features were combined in aspect of structural concept of light microscopical observation.

• Applied Microscopy
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• v.39 no.4
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• pp.283-289
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• 2009

In order to examine the effect of Injinhotang extract on the liver cancer induced by N-nitrosodiethylamine (NDEA) and carbon tetrachloride ($CCl_4$) in Rats. The animals were divided into three groups. The normal (Nor) group were fed basal diet. Control (Con) group were administered with NDEA (200 mg/kgb.w., i.p.) and $CCl_4$. Injinhotang extract (IJH) group treated with Injinhotang extract (260 mg/kg/day) for 8 weeks after NDEA+$CCl_4$. Enzymic antioxidants, such as superoxide dismutase (SOD) and catalase levels were determined in all the groups of animals. The activities of SOD were significantly increased in the Con, but the activities of catalase were decreased in the Con, but the anti-oxidative enzyme activities of superoxide dismutase and catalase were increased in the IJH. In the immunohistochemistry observation, treatment of Injinhotang extract reduced the rates of p53 immunoreactivity. According to the electron microscopical observation, in the liver cancer cells were increased the smooth endoplasmic reticulum and dilated the rough endoplasmic reticulum in the Con compared with IJH. These results suggest that administration of Injinhotang extract suppress or retard NDEA and $CCl_4$-induced liver cancer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.318-323
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• 2004

This study has been carried out to investigate the effect of the beverage contained Radix puerariae (15%) and Bambusae caules in Liquamen Phyllostachyos (1%) on the alcohol administered mouse. The control group was treated with alcohol (40% alcohol, 8.0 mL/kg of body weight), experimental group 1 (Exp.1) was administered with beverage (8.0 mL/kg of body weight) before alcohol treatment, and experimental group 2 (Exp.2) was administered with beverage after alcohol treatment. Blood alcohol concentrations were decreased by 11% (in Exp. 1) and 17% (in Exp. 2) compared with control group. The concentrations of serum aspartate aminotransferase (AST) were slightly increased in Exp. 1 and Exp.2, but alanine aminotransferase (ALT) levels were not changed compared with control group. Mn-Superoxide dismutase activity was increased by about 70% in the experimental groups in comparison to control group. The Exp. 1 and Exp. 2 contained more periodic-acid Schiff (PAS)-positive materials than the control group. Electron microscopical observations showed that, cell organelles of hepatocytes were more disoriented in the control group than in Exp. 1 and Exp. 2. These results suggest that the beverage contained Radix puerariae and Bambusae caules in Liquamen Fhyllostachyos is a safe and effective therapeutic agent for alcohol abuse.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1638-1641
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• 2005

In order to develop novel food products or additives using transglutaminase (TGase), some physicochemical and morphological understandings are needed. Raw skim milk was adjusted to pH 5.5, 7.0, and 8.5, and each was treated with microbial TGase for 0, 1, 2, 4, and 8 hours, for the protein structure observation using scanning electron microscope (SEM), The particles of untreated raw skim milk were small and evenly associated. After adjustment of pH to 5.5 and treatment of TGase for 1-hour, the protein particles aggregated widely in a bigger form than that of control. Under the same condition for 2 hours, the particles associated and clustered. The particles gathered widely and became a number of small spherical forms after 4 hours. After 8 hours, they made larger forms than the result of 1-hour treatment, and the aggregation broadened. Under the pH 7.0 and 8.5 conditions with TGase-treatment, the protein Particles fractionated and associated into the bigger masses at 1 hour point, but each piece slowly became smaller and more fractionated until treated time reached 4 hours. After 8 hours, the fragmented protein particles aggregated into larger forms as those on the pH 5.5 condition. In general, the electron microscopical forms of the samples adjusted to pH 5.5 showed smaller than those of pH 7.0 or pH 8.5, It is suggested that the protein particles and textural behavior were influenced by pH, TGase, and reaction time.

• Applied Microscopy
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• v.27 no.4
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• pp.433-452
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• 1997

Mongolian gerbil (Meriones unguiculatus) has been as an animal model for studing the neurological diseases such as stroke and epilepsy because of the congenital incompleteries in Willis circle, as well as the investigation of water metabolism because of the long time-survival in the condition of water-deprived desert condition, compared with other species animals. In order to accomplish the this research, first of all another divided the laboratory animals 5 groups of which each group include the 5 animals. In this study were investigated the histological structure in the kidney, measured the plasma osmolalities at the time of sacrifice of indivisual animals, and the body weights every day during water-deprived. The results obtained in this study were summarized as followings: 1. The body weights and decreasing rates of the body weight in water-deprived mongolian gerbil groups were continuosly decreased. 2. The plasma osmolalities were increased from the 5th water-deprived day, after then the gradually increasing reached nearly its equilibrium state at the 10th water-deprived day. 3. The urine volumes were abruptly decreased from the 2th water-deprived day, after then the gradually decreasing patterns were reached nearly its equilibrium state at the 10th day, and stopped the 11th day. 4. In the light microscopical observation of the kidney, glomerular capillary loop thickening, mesangial matrix increasing, sclerosis, glomerular cystic atrophy, interstitial fibrosis, tubular dilatation, mononuclear interstitial inflammation, interstitial mineralization, and hyperplasia of the collecting duct epithelium in the cortex area, were observed from the 10th water deprived day, and the lesions were gradually severe changed as the time lapse. 5. In the electron microscopical findings of the kidney, the degenerative changes of endothelial cell, podocyte and mesangial cell in glomeruli were initially observed on the 10th water-deprived day as well as the degeneration of microvilli and intracellular organelle in the renal tubules.

• Journal of Photoscience
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• v.9 no.2
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• pp.158-161
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• 2002

UV-B radiation gives harmful effects on plants, such as production of several types of DNA lesions, and growth inhibition. On the other hand, plants have some protective mechanisms, including filtering effect due to accumulation of phenolic compounds in epidermal cells and reactivation of DNA lesions, which are enhanced by UV-B irradiation. We have investigated the mechanism of UV-B effects on plants using cucumber seedlings as plant materials. Cucumber plants were cultivated in an artificially lit growth chamber. Supplemental UV-B irradiation, of which intensity was almost equal to the level of natural sunlight, retarded the growth of first leaves. The growth retardation must result trom the inhibition of cell division and/or cell growth. Microscopical observation of leaf epidermis suggested that the growth retardation might be mainly caused by cell growth inhibition. The retardation was, however, restored within 2 or 3 days after the termination of UV-B irradiation. It is known that UV-B irradiation lowers the activity of photo system II (PS II). In the present experimental conditions, however, UV-B irradiation has little effect on PS II activity as estimated by chlorophyll fluorescence. The stomatal conductance, a major factor determining photosynthetic rate, of first leaves increased during the growth. The increase of stomatal conductance was suppressed by UV-B irradiation and restored by termination of the irradiation. It has not been clear, however, what mechanisms are involved in the suppression of increase of stomatal conductance.

• Journal of the korean society of oceanography
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• v.34 no.2
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• pp.95-112
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• 1999

To investigate a phytoplankton community structure and its biomass distribution in the Korea Strait, phytoplankton pigments were quantitatively measured by HPLC method, with hydro-graphic conditions in August and October, 1996. The measured chi. a concentrations were in the range of 7.1-1,280.7 ng/1. Horizontal distribution pattern of chi. a in summer (August) was very different from that of autumn (October). High concentration of chi. a occurred near the coast with relatively low salinity (< 33%). Vertically, the highest concentrations of pigments at most of the stations were found near the surface and above the thermocline. The maximum concentration of chi. a in October was four times higher than in August. It was notable to measure relatively high concentration of chi. b up to 190.8 ng/1 in the study area, since chi. bcontaining green algae and prochlophytes have been ignored because of their minute size and sensitivity to common preservatives. Major carotenoids detected were fucoxanthin, zeaxanthin, 19'-hexanoyloxyfucoxanthin, and prasinoxanthin. Diatoms were the dominant group with secondary important groups as pryrnnesiophytes and cyanobacteria for the biomass of phytoplankton for both cruises. The dominant species of diatoms in summer were Thalassiosira sp. and Chaetoceros peruvianus. As minor groups, prasinophytes, crysophytes, and cryptophytes were confirmed by their marker pigments and dinoflgellates by microscopical observation. Degradation products of chi. a was minor. Interestingly, at 200 m depth of St A4, the deepest station in the western channel of the Korea Strait, substantial amounts of chi. a including fucoxanthin, 19'-hexanoyloxyfucoxanthin, chi. b, and degradation products of chi. a was measured from both cruises. Higher concentration (2-3 times) of those pigments were detected from samples in summer than in autumn. Small decrease in concentration of phosphate at this depth of St. A4 was also observed. It suggested that this bottom cold water was transported from the subsurface water with biomass of active phytoplankton, which was sunk and flowed southward.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.62-67
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• 1986

This electron microscopical study was carried out to observe the plasmodesmata of endosperm cells and epicuticular waxes of pericarp ribs on lettuce seed. The morphological modification of pericarp and pericarp ribs was detected by SEM observation. The seed which formed under low temperature, has well developed, suberized cell walls and epicuticular waxes while the seed fromed under high temperature condition has very poorly developed epicuticular waxes. Epicuticular waxes was considered to take over the function of seed protection and keeping the good quality during storage period. The plasmodesmata of endosperm cells in lettuce seed was observed at 4hrs after imbibition for the first time. This phenomenon indicates that the lettuce seed starts its physiological activities in the very early imbibition stages.

• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.102-107
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• 2001

This study was carried out to explore for the possibility of recycling the pine wood sawdusts for the substrate for enokitake (Flammulina velutipes) cultivation. The wood species of sawdusts cultivated for enokitake mushroom were identified mostly as hard pine (Pinus spp.). Distribution of enokitake hyphae was restricted to ray parenchymas and tracheids exposed to fungi. Nevertheless, degree of cell wall degradation by enokitake was slight. Light microscopic observation showed the thinning of secondary cell wall in some tracheids. Under polarized microscopy the 1()ss of birefringence was observed only in a few latewood tracheids. All the middle lamella remained intact. The present work showed clearly that pine sawdusts used as substrate for enokitake cultivation held enough cell wall materials for mushroom cultivation. The relative resistance of softwood cell walls against enokitake fungus was also discussed.