• Journal of fish pathology
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• v.8 no.1
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• pp.57-67
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• 1995

Twenty-four hours, acute toxicity and the histopathological effect of formaline to flounder, Paralichthys olivaceus larvae were examined. The $LC_{50}$ values obtained to farmaline were 2,520 ppm in 1 hour treatment. 1.610 ppm in 2 hours treatment, 868 ppm in 4 hours treatment and 141 ppm in 24 hours treatment. Many pathological features such as hypertrophy of mucous and epithelial cells in secondary gill lamella, hyaline droplet degeneration of tubular epithelial cells in the proximal convoluted segment of renal tubules, focal or massive necrosis in liver cells and pycnotic nucleus in heart cells were recognized. The above results were discussed in relation to the application of formaline as therapeutic agent in flounder disease.

• The Korean Journal of Mycology
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• v.27 no.1 s.88
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• pp.32-38
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• 1999

A Saprolegnia sp. was isolated from cultured snakehead, Channa argus, and its physiological characteristics were investigated. The optimum temperature, pH and NaCl concentration for mycelial growth of Saprolegnia sp. were $25^{\circ}C$, 6.0 and 0%, respectively. The mycelial growth was increased with the addition of 10 mM phosphate and 10mg/L casamino acid. The essential oils extracted from three plants, Artemisia princeps var. orientalis, Thuja orientalis and Chamaecyparis obtusa have been tested to know whether they inhibit the growth of Saprolegnia sp. at six different oil concentrations(10, 100, 500, 1,000, 1,500 and 2,000 ppm). Essential oil from A. princeps var. orientalis began to inhibite the mycelial growth of Saprolegnia sp. at the concentration more than 10ppm. Using other essential oils from T. orientalis and C. obtusa, those initially inhibited the mycelial growth of Saprolegnia sp. at the concentration over 10 ppm and complate inhibition of mycelial growth was observed at over 500 ppm. The histopathological features of Snakehead infected by Saprolegnia sp. were studied. A club shape of gill lamella epithelial cells was observed in the gill. The mycelial cells were penetrated into muscular tissue, and the accumulation of the ceroid was observed in the liver, spleen and kideny tissue in common. The necrosis of tubular epithelial cells was seen in the liver tissue, parenchymal tissue in the spleen and tubular epithelial cells in the kidney.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.6
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• pp.509-515
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• 2004

Photodynamic therapy(PDT) has advanced to clinical trials for the treatment of a variety of solid tumors and presents an alternative treatment option for tumors resistant to chemo-and/or radio-therapy. PDT is based on the combination of laser light of appropriate wavelength and energy to activate a systemically or locally applied photosensitizer that concentrates preferentially in malignant tissues. In this study, phototoxicity of laser EIT 21 was analysed in human osteosarcoma cell(HOS) and the second objective of this study was to determine the ability of laser EIT 21 to induce apoptosis. This study demonstrated that laser EIT 21 had a phototoxicity to HOS cells. In order to examinate whether cell death was induced by necrosis or apoptosis, variety of techniques which assess apoptosis were used. TUNEL assay showed only a few the positive reaction on condensed nuclei. It is hard to find condensed or fragmented nuclei on HOS cells irradiated with laser EIT 21 in Hemastat and AO/EB stain. By DNA electrophoresis, cells also did not show DNA degradation characteristic of apoptosis with a ladder pattern of DNA fragments. Apoptosis-related factors were analyzed by western blotting. The expression of p53 was constant and cells irradiated with laser did not show the caspase-3 and PARP degradation, therefore we suggest that p53 and caspase-3 are not involved in laserinduced cell death.

• Tuberculosis and Respiratory Diseases
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• v.63 no.1
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• pp.52-58
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• 2007

Background: Photodynamic therapy is a viable option for lung cancer treatment, and many studies have shown that it is capable of inducing cell death in lung cancer cells. However, the precise mechanism of this cell death has not been fully elucidated. To investigate the early changes in cancer cell transcription, we treated A549 cells with the photosensitizer DH-I-180-3 and then we illuminated the cells. Methods: We investigated the gene expression profiles of the the A549 lung cancer cell line, using a DEG kit, following photodynamic therapy and we evaluated the cell viability by performing flow cytometry. We identified the genes that were significantly changed following photodynamic therapy by performing DNA sequencing. Results: The FACS data showed that the cell death of the lung cancer cells was mainly caused by necrosis. We found nine genes that were significantly changed and we identified eight of these genes. We evaluated the expression of two genes, 3-phosphoglycerate dehydrogenase and ribosomal protein S29. The expressed level of carbonic anhydrase XII, clusterin, MRP3s1 protein, complement 3, membrane cofactor protein and integrin beta 1 were decreased. Conclusion: Many of the gene products are membrane-associated proteins. The main mechanism of photodynamic therapy with using the photosensitizing agent DH-I-180-3 appears to be necrosis and this may be associated with the altered production of membrane proteins.

• Proceedings of the Korean Nutrition Society Conference
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• 2004.05a
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• pp.93-93
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• 2004

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.137-148
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• 1992

The purpose of this study was to evaluate the influence of phenobarbital(PB) on hepatotoxic effect of carbon tetrachloride($CCl_4$) which induces centrilobular necrosis in liver. Rats were injected intraperitoneally $CCl_4$ dissolved in olive oil by a dose of 0.4mg/kg. For change related to PB pretreatment, rats were injected $CCl_4$ 0.4mg/kg after PB pretreatment. The liver samples were taken in 6, 12, 24, 48, 72, and 120 hours after $CCl_4$ and/or FB injection. Extracted liver tissue was examined with light and electron microscopes. The results were sumarized as follows : 1. Light microscopic findings : In $CCl_4$ group, centrilobular necrosis developed from 6 hours after injection, was the most severe in 48 hours, and recovered after 72 hours. In addition to necrosis, fatty change and pale cell change were accompanied. In PB-$CCl_4$ group, necrosis occurred from 6 hours after $CCl_4$ injection and continued to 72 hours, and the degree of necrosis was more severe than that of $CCl_4$ group and pale cell change was decreased. 2. Electron microscopic findings: In $CCl_4$ group, the early principal change was clumping and vesicular dilatation of endoplasmic reticulum. In PB-$CCl_4$ group, the degenerative change of endoplasmic reticulum was aggrevated and the mitochondria also revealed severe degenerative change. According to the results, it was revealed that $CCl_4$ hepatotoxicity primarily began with the damage of endoplasimic reticulum, then damage of other cell organelles and cell necrosis followed, and these cytotoxic effects were aggrevated by PB pretreatment.

• Parasites, Hosts and Diseases
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• v.33 no.2
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• pp.131-134
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• 1995

When tachyzoites (RH strain) of Toxoplasmo gondii are injected intramuscularly, experimental mice survive up to 7 days, 1-2 days longer than those infected intraperitoneally. We observed sequential histopathological changes in inguinal Iymph nodes after intramuscular injection of tachyzoites to thighs of specific pathogen free (SPF) mice. Initial findings on 1 or 3 days after the injection were reactive germinal centers, distended sinuses and epithelioid cell clusters in cortical and paracortical regions. Later on 5 days after the injection, however, effacement of nodal structure with depletion of cells and focal necrosis were observed . Necrotizing Iymphadenitis in the experimental murine toxoplasmosis suggests the causal relation between T. gondii infection and the human disease.

• Korean Journal of Veterinary Research
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• v.16 no.1
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• pp.27-34
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• 1976

악상남도(惡尙南道) 김해군(金海郡) S 양돈장(養豚場)에서 1975년 4월 하순부터 5월 하순 사이에 사육돈(飼育豚) 1,200두중 약 350두에서 출혈성하리(出血性下痢)를 주증(主症)으로 하는 전염성(傳染性)이 강한 소화기질환(消化器疾患)이 발생하였다. 환돈(患豚)은 7주령(週齡)에서부터 14주령(週齡)까지에서 가장 많이 발생하고 급성(急性) 또는 아급성(亞急性)으로 경과하였으며 다량의 황백색(黃白色), 수양하리(水樣下痢)를 발하다가 황갈색(黃褐色), 포말성하리(泡沫性下痢) 또는 암적갈색(暗赤褐色) 점액성하리(粘液性下痢)를 나타내었다. 육안적(肉眼的) 병변(病變)은 대장(大腸)에 한하였으며 카타아르성(性), 출혈성(出血性) 내지 괴사성장염(壞死性腸炎)을 시현(示顯)하였으며 괴사(壞死)는 광범(廣凡)하나 표재성(表在性)이고 어떤 예에서는 결장점막(結腸粘膜) 속에 대소(大小)의 미세결절(微細結節)이 밀발(密發)한 것이 특징이었다. 조직학적검사(組織學的檢査)에서는 대장점막(大腸粘膜)에 현저한 배세포증식(杯細胞增殖), 울혈(鬱血) 및 원형세포침윤(圓形細胞浸潤)과 더불어 표재성괴사(表在性壞死)가 관찰되었고 상기(上記) 결절(結節)은 장선(腸腺) 속에 점액(粘液), 섬유소(纖維素) 및 붕괴세포(崩壞細胞)가 축적되어 선와(腺窩)가 확장되고 피복상피(被覆上皮)의 이형성(異形成)(dysplasia)을 일으키고 있음이 판명되었다. 병변부(病變部)의 세균염색(細菌染色)에 의하여 대형(大型) Spirocheta와 Vibrio 고균(孤菌)이 무수(無數)히 발견되었고 Spirocheta가 병변형성(病變形成)에 더 밀접하게 관련되어 있음이 밝혀졌다.

• Korean Journal of Veterinary Research
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• v.29 no.1
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• pp.75-79
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• 1989

The etiologic agents of mucormycosis are several nonpathogenic fungi of the order Mucorales and are ubiquitous. A total of 82 chickens were infected with the disease and developed anorexia, diarrhea, malnutrition, dyspnea, and paralysis in a chicken farm, Sokcho, Kwangwon. At necropsy there were multiple nodular lesions and hemorrhages in livers, spleens, kidneys, gastrointestinal track, and respiratory system. On histopathological examination it was found that the nodular lesions were consisted of granoulomatous inflammation accompanying characteristic hyphae ($4{\sim}24{\mu}$ wide) of the fungi.

• Journal of Life Science
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• v.22 no.8
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• pp.1018-1023
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• 2012

Snail is a zinc finger transcription factor that induces epithelial-to-mesenchymal transition (EMT), which promotes tumor invasion and metastasis by repressing E-cadherin expression. In addition, Snail restricts the cellular apoptotic response to apoptotic stimuli or survival factor withdrawal; however, its molecular mechanism remains largely unknown. In this study, we have investigated the mechanism underlying Snail-mediated chemoresistance to 5-fluorouracil (5-FU), one of the most widely used anti-cancer drugs. When Snail was overexpressed by doxycycline (DOX) in MCF-7 #5 cells, it inhibited 5-FU-induced apoptotic cell death and switched the cell death mode to necrosis. Snail expression, either by DOX treatment in MCF-7 #5 cells or by the transfection of Snail expression vectors pCR3.1-Snail-Flg, phosphorylation-resistant pCR3.1-S104, and 107A Snail-Flg in MCF-7 cells specifically induced PTEN down-regulation/inactivation and Akt/PKB activation, without affecting ERK1/2 activity. In addition, Snail prominently suppressed 5-FU-induced increases in p53 levels. These findings demonstrate that Snail switches 5-FU-induced apoptosis to necrosis through the activation of Akt/PKB and the down-regulation of p53 levels.