• The Plant Pathology Journal
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• 제32권2호
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• pp.85-94
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• 2016

Studies were conducted to determine the role of 3-methylthioproprionic acid (MTPA) in the pathogenicity of potato stem canker, Rhizoctonia solani, and the concentrations required to inhibit growth of R. solani under laboratory and plant house-based conditions. The experiments were laid out in a completely randomized design with five treatments and five replications. The treatments were 0, 1, 2, 4, and 8 mM concentrations of MTPA. The purified toxin exhibited maximal activity at pH 2.5 and $30^{\circ}C$. MTPA at 1, 2, 4, and 8 mM levels reduced plant height, chlorophyll content, haulm fresh weight, number of stolons, canopy development, and tuber weight of potato plants, as compared to the control. MTPA significantly affected mycelial growth with 8 mM causing the highest infection. The potato seedlings treated with MTPA concentrations of 1.0-8.0 mM induced necrosis of up to 80% of root system area. Cankers were resulted from the injection of potato seedling stems with 8.0 mM MTPA. The results showed the disappearance of cell membrane, rough mitochondrial and cell walls, change of the shape of chloroplasts, and swollen endoplasmic reticulum. Seventy-six (76) hours after toxin treatment, cell contents were completely broken, cytoplasm dissolved, and more chromatin were seen in the nucleus. The results suggested that high levels of the toxin concentration caused cell membrane and cytoplasm fracture. The integrity of cellular structure was destroyed by the phytotoxin. The concentrations of the phytotoxin were significantly correlated with pathogenicity and caused damage to the cell membrane of potato stem base tissue.

• Applied Microscopy
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• 제25권1호
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• pp.1-14
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• 1995

The purpose of this study was to investigate the main sensory trigeminal nucleus in the aging rat brain by means of electron microscope. Male Sprague-Dawley rats, two (control group) and thirty six (aging group) months of age, were used. These animals were sacrificed by perfusion fixation with 2.5% glutaraldehyde-2.0% paraformaldehyde (0.1M phosphate buffer, pH 7.4) under sodium pentobarbital. The objective area was punched out with a sharp-edged metal cylinder of 0.8 mm in diameter. These blocks of tissue were then washed in 0.1M phosphate buffer, postfixed in 2% osmium tetroxide, dehydrated in a graded series of ethyl alcohol, and embedded in Epon 812. Thin sections were cut with Super Nova ultramicrotome, pick up on grids and double stained with lead citrate and uranyl acetate, and observed in JEOL 100B electron microscope. The results were as follows: 1. In the control group, the neuronal cell body of the main sensory trigeminal nucleus was filled with nucleus, Golgi complex, Nissl substance, mitochondria, microfilaments and microtubules. However, few Nissl substances are seen in neuronal cell body. Axoaxonic synapse, axodendritic synapse, axosomatic synapse, axospinous synapse, myelinated and unmyelinated nerve fibers were well organized around cell bodies. Neurons with abnormal changes were not seen. 2. In the aging group, the neuronal cell body of the main sensory trigeminal nucleus contained large number of lipofuscin granules, dense body and swollen mitochondria. Terminal boutons contained glycogen, crystal-like vesicle and membranous indicating first signs of degeneration. The dendrites were found to be in synaptic contact with altered axon terminals. Frequently axons filled with dark axoplasn and splitted myelin sheath were noticed.

• 대한수의학회지
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• 제45권3호
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• pp.445-450
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• 2005

A 1.35 kg, three-year-old, female, Yorkshire terrier was referred to the veterinary medical teaching hospital of Chungnam National University with an alopecia, scale, polydipsia and polyuria. During hospitalization, the patient revealed swelling and pain of all four foot pads. The hematology indicated nonregenerative anemia. Blood serum chemistry revealed elevation of BUN, serum creatinine and phosphorus contents. Radiographs of feet revealed increased radiodensity in the soft tissue of the foot pad. In ultrasonographs of abdomen, kidneys showed diffusely echodense renal cortex with loss of the normal corticomedullary boundary. Fine needle aspiration of the swollen pad cysts contained a amorphous basophillic chalky, white and pasty material. The culture result was negative for bacteria. In conclusion, it was diagnosed as metastatic calcinosis circumscripta secondary to chronic renal failure. An oral charcoal absorbent and aluminum hydroxide were used to treat this condition. After six weeks treatment, hyperphosphatemia was corrected and metastatic calcinosis circumscriptawas not presented any more.

• 한국발생생물학회지:발생과생식
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• 제23권2호
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• pp.93-99
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• 2019

Nonylphenols (NPs) are widely used industrial materials, and are considered as potent endocrine disrupting chemical. Present study was undertaken to clarify the effect of subchronic low-dose NP exposure to F1 generation male mice. Mice were divided into 2 groups; (1) CON, control animals and (2) NP-50 ($50{\mu}g/L$), animals were treated with NP via drinking water. NP exposures were continuously conducted from parental pre-mating period until the postnatal day (PND) 55 of F1 offsprings. Mice were sacrificed on PND 55 and the tissue weights were measured. The initial body weights (at PND 21) and terminal body weights (PND 55) of the NP-50 animals were significantly lower than those of control animals (p<0.05). NP exposure induced a significant increase in the absolute weight of the testes (p<0.05). Conversely, the NP exposure caused significant decrease in the absolute weights of the epididymis (p<0.01), prostate (p<0.05) and seminal vesicle (p<0.05). Histopathological studies revealed that NP-treated animals exerted decreased seminiferous tubule diameters, reduced luminal area, and lower number of germ cells. Also some sloughing morphologies in the tubules were observed. In the caudal epididymis, fewer mature sperms and swollen epithelial cells were found in the NP-treated group. Our results confirmed that the subchronic low-dose NP exposure altered some male parameters and induced histopathological abnormalities in testis and epididymis of F1 mice. Since the NP dose used in this study is close to the average human daily NP exposure, our results could provide practically meaningful understanding of adverse effect of EDC in human.

• 한국발생생물학회지:발생과생식
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• 제23권3호
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• pp.255-262
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• 2019

Previously, we reported negative effects of low-dose nonylphenol (NP) exposure on the reproductive organs of F1 male mice. In the present study was further investigated the endocrine disrupting effect of NP exposure to F2 generation male mice. Mice were divided into 2 groups; (1) CON, control animals and (2) NP-50 ($50{\mu}g/L$), animals were treated with NP via drinking water. NP exposures were continuously conducted from parental pre-mating period until the postnatal day (PND) 55 of F2 offsprings. Mice were sacrificed on PND 55 and the reproductive tissue weights were measured. The initial (at PND 21) and terminal (PND 55) body weights of the NP-50 group animals were not significantly different from those of control group animals. NP exposure fail to induce a significant weight change of the testes, seminal vesicle and prostate except absolute epididymal weight (p<0.05). However, pathohistological studies revealed that NP-treated F2 animals showed evident decrease in seminiferous tubule diameters, reduced luminal area and number of germ cells. Also, sloughing morphologies in the tubules were notable. In the caudal epididymis, fewer mature sperms and swollen epithelial cells were found in the NP-treated group. The present study demonstrated that the subchronic low-dose NP exposure induced pathohistological abnormalities in testis and epididymis of F2 mice, and we assumed that these 'qualitative' changes in reproductive tissues could be derived from the epigenetic modifications such as DNA methylation, histone modification, altered DNA accessibility and chromatin structure. Further studies are needed to achieve a better understanding on the multi- or trans-generational effects of NP on the reproductive health and a human application.

• 한국패류학회지
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• 제22권2호
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• pp.157-165
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• 2006

바지락의 중금속의 농축 방식 및 해독기작을 연구하기 위해 소화선, 소화관 및 아가미등 세 기관을 선택하여 면역조직화학적 방법, 미세구조적 연구 그리고 SEM-EDS를 사용한 MT와 중금속의 분포 양상을 지역별로 채집한 샘플과 Cd-Cu에 시간별로 노출시킨 샘플에서 각각 살펴보았다. 중금속에 의해 유도된 MT 단백질이 면역조직화학적인 방법에 의해 붉은 색으로 표지되었다. 노출시간이 길어질수록 간췌장에서는 diverticula의 외곽으로 강한 반응을 보였으며, 아가미에서는 중금속의 노출시간이 길어질수록 노출되지 않은 조직에 비해 전반적으로 더 넓은 지역에서 강하게 반응을 보였다. 간췌장과 아가미를 투과전자현미경으로 관찰한 결과 중금속(Cd) 에 더 오래 노출될수록 세포질에서 inclusion body와 중금속으로 추정되는 과립들을 다수 관찰할 수 있었으며, 핵막이 swelling 되는 현상을 관찰할 수 있었다. 또한 발달된 조면 소포체와 미토콘드리아가 관찰되었다. SEM-EDS 결과 중금속의 분포 양상이 지역별로 상당히 상이한 결과를 나타났는데, 이는 지역별로 중금속의 오염정도와 오염원이 되는 중금속의 종류가 다르기 때문으로 추측된다. 그리고 지역별로 채집한 바지락을 이용한 실험과 S와 Zn의 수치가 높게 나타나는 것으로 보아 MT가 관여하고 있음을 간접적으로 확인할 수 있었다.

• Journal of Nutrition and Health
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• 제39권7호
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• pp.599-609
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• 2006

In this study, we investigated the in vivo effect by intake of the irradiated foods such as mackerel and sesame seed which are high in unsaturated fatty acid through TBARS (thiobarbituric acid reactive subtance) and the tissue pathological and genotoxicological test. Thirty two ICR mice are divided into four groups, one non-irradiated (control) group and three irradiated (5, 10, 20 kGy, respectively) groups. Sesame seed and pulverized mackerel in modified AIN93M diet were mixed together then divided into four identical parts. Three parts of them were irradiated by doses of 5, 10, and 20 kGy. These experimental diet were fed to each group for 4, 8 and] 6 weeks. The results of the study were as follows: No significant differences in weight gain were found in each group. Peroxide value of the irradiated diet was higher than that of the non-radiated one and also increased according to the storage period. TBA values in plasma, liver, kidney and Peyer's patch were not significantly different among 4 groups. DNA% in tail, tail length (TL) and tail moment (TM) values of the blood lymphocyte in 4, 8 and 16 week groups and the liver in 16 week group were much measured over the control DNA % in tail of kidney of 8 week group was significantly than the control and TL and TM of 8 week and TM of 16 week groups showed a tendency of higher values. By Peyer's DNA % in tail of 8 week group, DNA % in tail and TM of 16 week groups increased significantly over the control, Ultrastructural examination shows myeline figures and swollen mitochondria in parietal cells and intestinal epithelial cells of 8 and 16 weeks groups. After this study, we need further investigations on the safety of highly consumed foods which contain high contents of unsaturated fatty acid, largely imported and which are possible to be irradiated.

• Applied Microscopy
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• 제22권2호
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• pp.1-14
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• 1992

This experiment was performed to study the morphological responses of the parafollicular cells of rat following X-ray irradiation. Male rats were divided into normal and experimental groups. The head and neck region of the rat, under sodium thiopental anesthesia, was exposed to 3,000 rads or 6,000 rads of radiation in a single dose, respectively. The source was a Mitsubishi Linear Accelerator ML-4MV. The target to skin distance was 80 cm, and the dose rate was 200 rads/min. The rate of experimental groups were sacrificed on the 6th hour, 2nd and 6th day after X-ray irradiation. Pieces of the tissue taken from the thyroid gland were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde (0.1M Millonig's phosphate buffer, pH 7.3), and in 1% osmium tetroxide (0.1M Millonig's phosphate buffer, pH 7.3), and embedded in araldite mixture. The ultrathin sections stained with uranyl acetate and lead citrate were observed with JEM 100 CX-II electron microscope. The results were as follow; 1. Two types of the parafollicular cells, according to their electron densities, were found, i. e., light cells and dark cells. 2. Three types of the parafollicular cells, according to their sizes of secretory granules were found, i.e., small granule cells ($85nm{\pm}20.1;64{\sim}102nm$), medium granule cells ($120nm{\pm}26.5;77{\sim}179nm$), and large granule cells ($165nm{\pm}25.7;128{\sim}189nm$). 3. The differential ultrastructural changes of the cells according to their cell types, i.e., dark and light cell, or small, medium and large granule cells, were hardly observed in the time and dose range covered by this study. 4. The morphological changes of the parafollicular cells were not pronounced after exposure to 3,000 rads of X-ray. 5. Swollen cisternae of the granular endoplasmic reticulum and partial cytolysis were observed after exposure to 6,000 rads of X-ray. 6. Above results suggest that the parafollicular cells showed the alterations of mitochondrial and granular endoplasmic reticular swelling, and partial cytolysis, but only in doses of 6,000 rads.

• 한국동물학회지
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• 제12권4호
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• pp.114-122
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• 1969

成體 albino 흰쥐를 實驗群과 對照群으로 나누어 對照群에는 0.9% 生理食鹽水를, 實驗群에는 methylene blue(38mg/kg, pH 7.4)를 各各 腹腔에 注射한 後 約 30 分後에 總線量 360 rads의 $^{60}Co-\gamma$ 線을 一時全身照射하였다. 照射後 64時間區 와 212時間區로 나누어서 肝 및 心臟組織을 觀察하였다. 照射直後 肝 및 心臟組織을 6% glutaraldehyde (pH 7.4)와 1% osmium tetroxide (pH 7.4)로 冷室에서 二重固定하였으며 脫水한 後 Epon 812로 胞埋하여 MT-2 Porter Blum ultramicrotome 으로 超薄切斷하여 切片을 만들었다. 이를 uranyl acetate 와 lead citrate 로 二重染色한후 Hi9tachi HU-11 E型 電子顯微鏡으로 觀察하였다. 64時間區의 methylene blue 處理群과 對照群에서 肝組織은 顯著한 組織學的 變化의 差를 나타냈다. 다시 말하면 methylene blue 處理群에 比하여 對照群에서는 mitochondria 의 膨大, cristae 의 切斷, endoplasmic reticulum 의 破壞를 觀察할 수 있었으며 또한 endoplasmic reticulum 에 glycogen 粒子의 蓄積을 觀察할수 있었다. 한편 methylene blue 處理群에 比하여 對照群의 212時間區에서도 같은 變化樣相을 나타냈으나 endoplasmic reticulum 에 많은 vacuole 이 形成되었음을 觀察할 수가 있었다. 그러나 methylene blue 處理群은 正當群($\gamma$ 線의 照射와 methylene blue를 處理하지 않음)에 比하여 若干의 差가 觀察되었을 뿐 顯著한 組織學的變化는 나타나지 않았다. 心臟組織에서는 兩群 卽 實驗群과 正當群사이에 顯著한 差는 別로 觀察할 수 없었으나 methylene blue 群에 比하여 對照群에 若干의 變化가 觀察되었다. 다시말하면 methylene blue 處理群에 比하여 64時間區의 對照群에서는 mitochondria의 若干의 膨大, cristae 에 若干의 切斷을 觀察할수 있었고 212時間區의 對照群에서는 sarcoplasmic reticulum에서 若干의 液胞와 glycogen 粒子의 若干의 增加를 觀察할수 있었다. 이로 미루어 보아 methylene blue 가 放射線에 對하여 防禦 果가 있는 것으로 思料된다.

• 한국임상수의학회지
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• 제30권3호
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• pp.214-217
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• 2013

3세령의 암컷 고슴도치(Atelerix albiventris)가 심하게 종대된 하악 병변의 평가를 위해 내원하였다. 세포학적 검사를 위해 세침흡인을 실시하였으며, 도말표본을 제작 후 로마노프스키식 염색으로 염색하였다. 세포학적 검사에서 원형을 포함한 다양한 모양의 편평상피세포가 주로 관찰되었으며, 일부 세포는 유사 방추 모양 또는 매우 길쭉한 모양을 띄고 있었다. 세포학적 소견은 편평상피암종이었으며, 조직검사를 위해 수술적으로 제거하였다. 조직병리상 악성 편평상피암종세포들이 중등도의 콜라겐과 방추형 섬유모세포로 이루어진 간질에 둘러싸여 있었으며, 인접한 골격근과 골조직으로의 침습이 관찰되었다. 종양세포는 중등도의 세포 대소부동과 핵 대소부동을 보였으며, 중등도 이상의 각화상태를 보였다. 종양의 중심부에서는 극세포해리가 있었으며 림프형질세포 및 호중구성 염증소견이 동반되었다. 유사 분열상은 고배율에서 2-3개가 관찰되었다. 이와 같은 소견에 기초해서 편평상피암종으로 진단하였으며, 보호자는 종괴의 수술적 제거 후 더이상의 치료를 원치 않아 바로 퇴원하였다. 환자는 추가 처치 없이 3개월 생존 후 폐사하였다.