• Animal Systematics, Evolution and Diversity
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• v.31 no.4
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• pp.277-283
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• 2015

Two pleurostomatid ciliates, Loxophyllum perihoplophorum Buddenbrock, 1920 and L. rostratum Cohn, 1866, were collected from the coastal waters of the East Sea, Korea. Their morphologies are described based on live observation and protargol staining, and morphometrics are provided. Loxophyllum perihoplophorum is characterized by the following features: 200-650 μm long in vivo; body slender leaf-shaped, flexible and contractile, with thin and wide extrusome-belted zone; 2 macronuclear nodules (Ma) and 1 micronucleus (Mi); 7-9 contractile vacuoles (CV) positioned along dorsal margin; extrusomes (Ex) evenly distributed along edge of entire body, with about 10 dorsal warts (Wa); 9-11 left (LSK) and 19-22 right somatic kineties (RSK), 4-5 furrows (Fu) on left side. Loxophyllum rostratum is about 100-130 μm long in vivo; body oblate leaf-shaped, contractile, convex ventral side and S-shaped dorsal side, beak-like anterior end; 2 Ma and 1 Mi; 1 CV terminally located; Ex distributed along edge of entire body, with about 9-10 dorsal Wa; 7-8 LSK and 15-19 RSK, ca. 5 Fu on left body side. In addition, sequences of small subunit ribosomal DNA were determined from these two Loxophyllum species and compared with the known Loxophyllum sequences.

• Animal Systematics, Evolution and Diversity
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• v.25 no.2
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• pp.167-178
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• 2009

Two poorly known and often confused pleurostomatid ciliates, Litonotus paracygnus Song, 1994 and L. pictus Gruber, 1884, were collected from the coastal waters of Yeonggeumjeong and Bongpo-port, Gangwondo in the East Sea and from the Iwon tide embankment near Ganwol-do, Chungcheongnam-do in the Yellow Sea, Korea. These species were described based on live observations, the protargol-impregnation and morphometrics of the species. Also provided are their diagnoses. The small subunit ribosomal DNA (SSU rDNA) sequences of these species were compared with previously known sequences of related species. The diagnostics of the two Litonotus species are as follows. L. paracygnus: 150-300 $\mu$m long in vivo, strongly contractile neck region, two ellipsoid macronuclei (Ma) and one micronucleus (Mi), 7 left (LSK) and 11-14 right somatic kineties (RSK), 2-4 contractile vacuoles (CV) located on the posterior end, extrusemes (Ex) distributed on the anterior region of the ventral margin only. L. pictus: about 200-600 $\mu$m long in vivo, extremely contractile, beautiful body color with rows of yellow to yellow-brownish cortical pigment granules, 12-21 Ma arranged in moniliform pattern, infrequently vermiform, 7-11 LSK and 18-26 RSK, several CV located on both margins, Ex distributed on the anterior region of the ventral margin only. In this study, this genus was firstly recorded in Korea.

• Korean Journal of Veterinary Research
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• v.16 no.2
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• pp.141-150
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• 1976

In order to know the morphological changes of liver in nitrate poisoning, the ultrastructural studies were carried out on the rabbit liver after potassium nitrate was administered orally at lethal dose, in single treatment, as acute case and at two different levels. 1.0 and 0.5g/kg of body weight daily for 43 and 60 days as chronic case, respectively, The results were summarized as followings: 1. In the hepatic cells of acute case, mitochondria were swollen, disappearance of cristae and variable in shape. Dilatation of rough endoplasmic reticulum and vacuoles containing degenerated cell organells were observed. Glyogen particles were decreased in number. Degenerated Kupffer cells were often seen in acute case. 2. In the hepatic cells of chronic case, there were increase of smooth endoplasmic reticulum, marked enlargement of rough endcplasmic reticulum, detachment of membrane bound ribosome and some rough endoplasmic reticulum changed into smooth endoplasmic reticulum. Secondary lysosome, abundant glycogen paricles and myelin-figure structures were also observed in the cytoplasm of the hepatic cells. The endothelial cells were proliferated in the area of the necrotic cells.

• Journal of Microbiology
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• v.45 no.1
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• pp.29-33
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• 2007

Salmonella typhimurium, causing mouse typhoid, infects hosts such as macrophage cells, and proliferates in intracellular vacuoles causing infected cells to trigger numerous genes to respond against the infection. In this study, we tried to identify such genes in RAW264.7 cells by using the PCR screening method with degenerate primers. Fourteen genes were found to be differentially expressed after a 4 h infection in which the expression of 8 genes increased while expression of the others decreased. Most of the genes were involved in proinflammatory responses such as cytokines production and cell death. The mutation in msbB gene encoding the myristoyl transferase in lipid A of lipopolysaccharide (LPS) resulted in much lower toxicity to the inoculated animals. We compared the expression of the identified genes in wild-type and msbB-mutated S. typhimurium infections and found that Lyzs encoding lysozyme type M was differentially expressed. This gene is quite likely to be related to bacterial survival in the host cells.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.719-725
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• 2019

To recover the discoloration of Pyropia yezoensis, additional NO₃^- and PO₄^3- nutrients were supplied to the discolored blades. As a result, the efficiency of photosynthesis was increased from two days after incubation with NO₃^- and five days after incubation with PO₄^3-. In addition, the chromaticity analysis results showed significant changes. Furthermore, the cell vacuoles bloated due to discoloration were reduced again when they were restored from discoloration, suggesting that the control of discoloration is feasible by nutrient supply.

• Applied Microscopy
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• v.13 no.1
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• pp.49-61
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• 1983

Protoplast releasing mechanisms from Trichoderma koningii, fine structures of the released protoplsts, and their regeneration mode were studied by scanning and transmission electron microscopy. Two types of protoplast releasing mechanisms were observed. In one mechanism, cytoplasm emerged through a cell wall pore developed by cell lytic enzymes and formed a spherical protoplast. In the other mechanism, as the cell wall became progressively thinner, the inner cytoplasm partially rounded to form nonspherical bodies which became spherical protoplasts after being released into the enzyme solution. But, these two types of protoplast releasing mechanisms did not seem to be. mutually exclusive but could occur on the same mycelium simultaneously. And it appeared that cytoplasm which did not become a protoplast by the first mechanism could from a protoplast by the second mechanism. The preparations contained two types of protoplasts, released from different sites of the mycelia. Those released from younger mycelia had dense cytoplasm and small vesicles. Those released from the older mycelia had less dense cytoplasm and larger vacuoles. In the case of regeneration, before producing normal mycelia, most of the protoplasts assumed aberrant tube and yeast-like-forms. Normal mycelia were produced at the end of the yeastlike-forms and sometimes in the middle of the aberrant tube.

• Applied Microscopy
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• v.27 no.4
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• pp.391-402
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• 1997

Using the electron microscopical method, this study was attempted to investigate the ultrastructural characteristics of glomeruli in FGS/Kist mice showing high proteinuria. The mucus-like substances were observed in glomerular capillary lumen which were usually narrowed by the widening of mesangial area filled with electron-dense deposits. Some portions of basal lamina in capillary wall were projecting to urinary space. Moreover, many vacuoles were observed in the cytoplasm of visceral epithelial cells, and an irregular-shaped fusion or effacement of foot processes were often shown in areas adjacent to basal lamina of glomeruli.

• Applied Microscopy
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• v.43 no.4
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• pp.140-145
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• 2013

Structural aspects of highly reduced vegetative organs in the aquatic Spirodela polyrhiza were examined using scanning and transmission electron microscopy. The study focused mainly on young and mature fronds with turions and their cellular features were compared. Mature fronds were composed of thin-walled chlorenchyma with highly vacuolated cells; most of which were frequently occupied by either tanniferous deposits or various crystals. Fronds of photoautotrophic offspring were produced from the meristematic region of the reproductive pockets within mother fronds, where they remained until separation. Moderate degrees of wall ingrowth and plasmalemma proliferation were detected briefly in the epidermis of daughter fronds during early development. Vascular tissues were generally much reduced, but air chambers were well-established in fronds. Chloroplasts having grana with several thylakoids were distributed throughout the plant, but starch grains were encountered frequently in the mesophyll chloroplasts of younger fronds and initial stage of the turion. Their cytoplasm was dense with small vacuoles in most cases. Further, big starch grains, up to several microns, occupying most of the plastid volume were formed in the turion prior to sink for overwintering. Plasmodesmata were numerous in the examined tissues, except mature turions, suggesting a symplastic pathway of the metabolites within body.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.131-136
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• 2004

This study was carried out to investigate effect of lipid metabolism in Viscum album lectin on rats. The lectin was purified by sepharose 4B affinity chromatography and gel filtration using sephadex G-150 with plant material from Viscum album collected in Mt. Duk Yui. After 72 h of $CCl_4$ injection (in olive oil, 1:1, 2 mg/kg) there was a significant increase in serum total cholesterol and triglycerige levels relative to the control group. However, treatment of both Viscum album and purified lectin were significantly decreased lipid parameters against the $CCl_4$-induced. Histological observation basically supported the result obtained from serum lipid assay. The livers of rats challenged with $CCl_4$ produced a marked increase of cytoplasmic vacuoles in number, while the number of necrotic cells and swollen hepatocytes did not change significnatly. Rats administered olive oil alone did not alter the normal hepatic architecture. Histological observation of the liver section in rats treated 72 h with either Viscum album purified lectin or $CCl_4$-induced liver lipogenesis showed decreased numbers of cytoplasmic vaculoes and necrotic cells. The normal hepatic architectural pattern was observed in Hematoxylin-eosin stain. These results suggest that Viscum album lectin has a possible protective effect of lipid metabolim in rats.

• The Korean Journal of Cytopathology
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• v.13 no.2
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• pp.88-92
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• 2002

Scattered single cells or variable sized clusters of signet ring cells in the aspirated smears of breast lesions are almost exclusively associated with carcinoma. The signet ring cells are defined as those containing a prominent intracytoplasmic vacuole or amorphous cytoplasm diffusely dispersed with mucin. The primary signet ring cell carcinoma of the breast behaves more aggressively than carcinoma without signet ring cells. Therefore, it is very important to make a correct diagnosis of signet ring cell carcinoma. Fine needle aspiration cytology is useful for diagnosis of breast lesions Including signet ring cell carcinoma. We report two cases, which showed mostly signet ring cells in the aspirated smears of the breast. One case consisted of numerous individual signet ring cells and variable sized cell clusters in rather mucoid background. The tumor cells had abundant amorphous cytoplasm filled with dispersed mucin or occasionally mucin vacuoles(PAS +) and eccentric nuclei. The resected mass revealed mucinous carcinoma. The other showed the cytologic findings of low cellularity, and small loosely cohesive signet ring cell clusters with mild nuclear pleomorphism. It was confirmed as lobular signet ring cell carcinoma in the resected tumor.