• Applied Microscopy
• /
• v.17 no.1
• /
• pp.47-64
• /
• 1987

Morphological difference of the renal glomerulus at different age groups have been studied in young (three month-old), adult (twelve month-old) and old (thirty month-old) Fisher strain 344 rats. Pieces of the tissues were taken from renal corticies prefixed with 2.5% glutaraldehyde-1.5% paraformaldehyde (0.1 M Millonig's phosphate buffer, pH 7.3), following by post-fixation with 1% osmium tetroxide (0.1 M Millonig's phosphate buffer, pH 7.3) and embedded within Araldite. The ultrathin sections contrasted with uranyl acetate and lead citrate were observed under a JEM 100CX electron microscope. The mean thickness of glomerular basal lamina and Bowman's capsule were determined by measuring the thinnest portion of basal lamina, and by taking the average of 50 readings from electron micrographs at different ages. The numerical changes of the slit pores were compared based upon the numbers over the length of 10um of glomerular basal lamina. The results were as follow: 1. The thickness of glomerular basal lamina is increased during aging; 140.4 nm in young rats, 270.0 nm in adult ones, and 437.8 nm in old ones. 2. The thickness of basal lamina of parietal cells of Bowman's capsule is 187.5 nm in young rats, 914.0 nm in adult ones, and 2850.0 nm in old ones. 3. The numbers of the slit pores of basal lamina are reduced during aging, 30.3 slit pores/$10{\mu}m$ in adult ones, and 24.2 slit pores/$10{\mu}m$ in old ones. 4. Accumulation of dense intracytoplasmic filamentous material in the parietal cells of Bowman's capsule is increased in the vicinity of the basal lamina during aging. The proximal tubule-like epithelial cell in Bowman's capsule is observed at one glomerulus in a young rat. 5. The endothelial cells are edematous and form balloon-like structure protruding into capillary lumen in young and old rats. 6. Cytoplasm of the podocyte shows a variety of alteration during aging, such as swelling of mitochondria and of endoplasmic reticulum, and increase of microtubules, microfilaments, lysosomes and lamellated myelin structures, etc. Accumulation of dense intracytoplasmic material in the foot processes is increased in the vicinity of the basal lamina during aging. The podocytic membrane-like structures are seen in young and o]d rats. 7. The mesangial matrices and mesangial cells are increased during aging, and slight swelling of endoplasmic reticulum and Golgi cisternae in young and old rats.

• Proceedings of the KSMRM Conference
• /
• 1999.11a
• /
• pp.69-71
• /
• 1999

최근 한국 의학의 발전은 전체 한국의 선진화를 선도하다고 보기에는 힘드리만 최소한 국제무대에의 진출은 괄목할만한 발전을 보이고 있다. 최근에 들어 국내 방사선영상과련 학회의 발전은 날로 비약적인 추세를 보이고 있다. 일례로 대한방사선의학회는 본 저자가 전공의 하던 1980년도 초기만 해도 호텔의 큰 홀 한 개만 빌려서 하루만 해도 넉넉하게 진행되었다. 그러나 최근의 학회사정은 대형호텔 1개층 통째로 빌리고 3일간 진행해도 여유가 없을 정도이며 더욱이 추계학회는 지방에서 유치할만한 공간이 부족하여 이제는 없어져야할 지경에 이러렀다. 그뿐 아니라 대한 자기공명의과학회를 포함한 각종 학회가 이제 그 규모를 더해가고 있어. 대한민국에 있어서 진단 방사선영역의 의학은 급속히 발전하여 RSNA, ISMRM등에서도 세계 발표순위가 4-5위권을 다투게 되었다. 이러한 발전은 양적인 발전이 우세하여 주로 임상연구에 기반을 두고 있는데 이 자체로는 장기적인 발전에 한계점이 있으므로 앞으로는 기초과학연구에 기초한 질적 발전을 같이 추구하여야만 균형있는 성장을 기대할 수 있겠다. 이러한 기존의 구성에 최근 급격한 변화를 주도하는 학문이 MRI부분이 되며 이 분야를 연구하는 PhD 들의 역할이 크게 대두되고 있다. 현재 국내에도 초기 단계이지만 MRI를 생산하고 있으며 PhD들의 활동이 성장단계에 접어들었다고 할수 있다. 과거 우리의 NRI역사에서는 금성사 MR기계처럼 육성되기 전에 시들며 노력하던 기술진이 흩어져야 했던 어두운 기억이 있다. 이러한 시점에서 우리의 힘들었던 과거를 돌이켜보며 또 하나의 기초부분이 육성되 수 있도록 서로가 격려하며 협조하여야 될 것으로 생각되어 다음과 같이 요약을 하였다. 소기관으로는 세포 막, 미토콘드리아 (mitochondria), endoplasmic reticulum, Golgi 체, lysosome, peroxisome 그리고 세포질등이 있으며, 이들중에서 lysosomes, peroxisomes, 그리고 미토콘드리아가 특정한 유전성 백질질환에 중요한 역할을 하는 것이 밝혀졌다. 이러한 질환들은 최소한 각 소기관에 의한 질환군으로 분류될 수 있다.SXR이 ER의 transactivation 효과를 약간 촉진한 반면 MDA-MB-231세포는 SXR을 제외한 CAR와 PPAR${\gamma}$에 의해 ER의 transactivation 효과가 약간 증가되는 경향을 보였다. 이러한 결과는 유방암세포에서는 CAR, SXR, PPAR${\gamma}$과 같은 xenobiotic nuclear receptor에 의한 ER transactivation 효과가 간암세포와는 다르게 나타나며, 유방암의 종류에 따라서 endogenous CAR, SXR, PPAR${\gamma}$수용체가 다르게 발현됨으로써 이들에 대한 반응이 서로 상이한 특징을 나타낼 수 있을 것으로 사료된다. 따라서 estrogen receptor에 의해 매개되는 estrogn의 전사활성조절기전이 표적세포에 따라 다른 경로를 포함 할 수 있음을 시사한다.서 흡착 능력이 우수하게 나타났으며, 황화수소는 펄라이트, 왕겨, 소나무수피에서 상대적으로 우수한 것으로 나타났으며, 혼합충전재는 암모니아의 경우 코코넛과 펄라이트의 비율이 7：3인 혼합 재료 3번과 소나무수피와 펄라이트의 비율이 7：3인 혼합 재료 6번에서 다른 혼합 재료에 비하여 우수한 것으

• Korean Journal of Microbiology
• /
• v.50 no.1
• /
• pp.27-32
• /
• 2014

Autophagy is one of the lysosomal degradation pathways to maintain cellular homeostasis. The damaged proteins or organelles are uptaken through extra- and intra-cellular stress, starvation and infected pathogens, subsequently, autophagosomes are fused with lysosomes to break down the molecules. Salmonella enterica serovar Typhimurium (S. Typhimurium), intracellular bacteria, cause acute gastroenteritis and food poisoning. Given that autophagy induced by S. Typhimurium plays an important role in the cells to control the infection, we identify whether the induction of autophagy with rapamycin, chemical inducer of autophagy, before infection regulates S. Typhimurium infection. After treatment of rapamycin or 3-methyladenine (3-MA), autophagy inhibitor, RAW264.7 cells were infected with S. Typhimurium. Pretretment of rapamycin decreased the growth rate of S. Typhimurium in the cells; otherwise, pretreatment of 3-MA increased the growth rate of S. Typhimurium. The expression of autophagy-related genes was significantly increased in the S. Typhimurium-infected cells pretreated with rapamycin. To examine whether induced autophagy by rapamycin control the infection with increase the production of reactive oxygen species (ROS) and nitric oxide (NO), antibacterial radical substrates were measured in infected cells followed by the treatment with either rapamycin or 3-MA. NO production increased in RAW264.7 cells; otherwise, ROS production remained unchanged during the infection. These findings suggest that inducing autophagy with rapamycin reveals antimicrobial activity as producing NO against S. Typhimurium infection in mouse macrophages.

• Korean Journal of Environmental Biology
• /
• v.25 no.4
• /
• pp.289-296
• /
• 2007

Di-(ethyhexyl) phthalate (DEHP), commonly used as a plasticizer for manufacturing flexible vinyl products, has been the topic of extensive research, especially concerning endocrine disrupting properties. Metallothionein (MT) is a low molecular weight (6,000$\sim$7,000 Da), cysteine-rich (22$\sim$23%), metal-binding protein and is known to be induced by extrinsic factors such as chemical agents and stresses. Some of the known function of MT include detoxification of heavy metals and alkylating agents and neutralization of free radicals. Nonetheless, the definitive physiological function of MT are still unknown. This study was carried out to investigate the effects of DEHP on the ultrastructural changes and the expression of MT of the rat liver. The rats were orally intubated with either corn oil (experimental control) or 0.5 mg, 1.5 mg and 4.5 mg DEHP kg$^{-1}$ day$^{-1}$ in 0.5 mL of corn oil for 15 days before sacrificing and sampling. DEHP induced mild ultrastrctural changes of some cell organelles such as rough endoplasmic reticulum, mitochondria, lysosomes and peroxisomes in the rat liver treated with DEHP. In the respect of immunogold labelling and Western blotting, MT expression of the liver tissue was up-regulated by DEHP. In conclusion, DEHP has effects on the ultrastructures and hepatic function for MT expression in rat.

• Applied Microscopy
• /
• v.27 no.2
• /
• pp.197-215
• /
• 1997

A morphologic study on the effect of butylated hydroxytoluene (BHT) on experimental hepatocarcinogenesis induced by 3'-methyl-4-dimethyl aminoazobenzene (3'-MeDAB) was investigated. A total of 110 Sprague-Dowley male rats weighting about 200 g each were used for the experiment, and divided into 4 groups; the 3'-MeDAB, BHT, 3'-MeDAB/BHT treated group, and the control group. Four to eight rats of each group were sacrified on the 4th, 8th, 14th and 16th experimental weeks, with continuous pelletized feeding containing 0.09% 3'-MeDAB and 0.5% BHT. The liver was examined by transmission and scanning electron microscopy. The results were as follows; Electron microscopically, the fine structure of the hepatocytes remained consistently abnormal up to 16 weeks after the 3'-MeDAB treatment. There was no significant difference in the groups observed earlier than in the ones observed later. Many subcellular changes were observed : nuclear change, decreased glycogen, mitochondrial abnormalities, disaggregated rough endoplasmic reticulum, marked proliferation of smooth endoplasmic reticulum, dilatation and distortion of bile canaliculi, increased lysosomes, apoptotic bodies, migration of bile ductule cell. In the BHT treated group, the ultrastructural changes of hepatocytes were not significant, except for the lipid droplets and proliferated smooth endoplasmic reticulum among hepatocytes depending on the experimental duration. The various subcellular changes of 3'-MeDAB/BHT treated groups were simillar to those of the 3'-MeDAB treated group, but the degree of changes in the 3'-MeDAB/ BHT treated group decreased compared with those of the 3'-MeDAB treated group. These results suggest that dietary butylated hydroxytoluene has a protective/inhibitory effect on the hepatocarcinogenesis induced by 3'-methyl-4-dimethyl -aminoazobenzene.

• Applied Microscopy
• /
• v.24 no.2
• /
• pp.48-62
• /
• 1994

The acute irradiation effect on rat Purkinje cell was carried out. Anesthetized rats, weighing 200-250g each, were exposed their heads to the linear accelerator (ML-4MV) with the doses of 3,000 rads or 6,000 rads respectively. Irradiated rats were sacrificed by perfusion fixation under anesthesia, six hours, two days and six days following the irradiations. Rats were perfused with the fixative of 1% glutaraldehyde-1% paraformaldehyde solution (pH 7.4). Small pieces of cerebellar cortices were taken out. Tissue blocks were washed out, and were refixed in the 2% osmium tetroxide solution. After dehydration, tissues were embedded in the araldite mixture. Ultrathin sections stained with uranyl acetate-lead citrate solution, were examined with an electron microscope. The results observed were as follow; 1. Many dark Purkinje cells exhibited most severe cellular alterations on 6 hours. But after the 2 or 6 days, the cells exhibited only some alterations of cytoplasmic organelles. 2. Many granular and agranular endoplasmic reticula exhibited the fusion of cisterns. These reticular alterations were most severe on 6 hours following irradiation. But the alterations were hardly found on 6 days. 3. In the Golgi region, alterations including the adhesion of lamelliform cisterns, enlarged saccules, and increased number of vesicles, etc, were seen on 6 hours. But the Golgi complexes were almost recovered on 6 days. 4. Lysosomes were abundant on 6 hours or 2 days, but some residual bodies were found on 6 days. 5. Mitochondrial changes were also most severe at on hours, and they were recovered thereafter. From the results, it was concluded that the cerebellar Purkinje cells reacted to the high doses of irradiation by hyperactive protein synthesis, autolytic activities and energy metabolism. The reaction was most active in the early stage. It implies that motor-control function of Purkinje cells are severely disturbed in the early stage of irradiation.

• Korean Journal of Animal Reproduction
• /
• v.17 no.3
• /
• pp.221-232
• /
• 1993

Morphological changes in the uterine and vaginal epithelial cells of the Korean native goats were studied in fifteen primiparous goats slaughtered on the day of parturition and on days 1, 3, 10 and 21 postpartum. 15 uterus and vagina from goats were examined by scanning and transmission electron microscopy. The results obtained in this study were summarized as follows : 1. Transmission electron microscopically, long microvilli which sometimes ramified were found until 10 days postpartum, while short microvilli were found at 21 days. The high electron dense irregular-shaped mitochondria were found in the cytoplasm and the crystalline structure of the mitochondrial matrix was also found from 1 day to 10 days postpartum. Well-developed rough-endoplasmic reticulum (rER) with dilated cisternae which contained the proteins materials was observed at 21 days postpartum. These materials were fused each other and then large granules were found in the free surface of the cytoplasm. A few lipid droplets were generally appeared in the cytoplasm, while numerous droplets were found at 21 days postpartum. A moderate number of ribosomes, a few multivesicular bodies, vesicles, lysosomes and macrophages were found. The globule leucocytes were observed from 0 to 3 days postpartum by transmission electron microscopy. The short microvilli, high electron dense cytoplasm and severe indentation of the nuclear enbelope were found in the vaginal epithelium. Numerouos small vesicles and a few vacuoles were observed in the apical cytoplasmic portion of the epithelium. A few mitochondria were high electron dense and irregular in shape. A moderate amounts of microfilaments, loose intercellular space and dilated rER were also found at 21 days postpartum. 2. Scanning electron microscopically, the folds of the uterine mucosa were generally deep. The long microvilli of the epithelium were found until 3 days postpartum, while short microvili were found at 10 and 21 days postpartum. The distinct intercellular boundary was seen. The apporcine secretory profile of the epithelium observed at between 3 and 10 days postpartum and the cells were somewhat protruded into the lumen. The short microvilli were found on the surface of the protruded cells, while polygonal microridge profile of the epithelium and some dome-shaped epithelium were also observed at 21 days postpartum. The folds of the vaginal mucosa were deep and epithelium was polygonal in shape. The microvilli of the epithelium were long until 3 days postpartum, while they were short at 10 and 21 days. The polygonal epithelium was invaginated into the center of the cell surface until 10 days postpartum. The microridge and dome in shape of the epithelium were found at 10 days postpartum, while the polygonal and exfoliating epithelium were observed at 21 days.

• Applied Microscopy
• /
• v.27 no.1
• /
• pp.13-30
• /
• 1997

The experiment was performed to study the morphological responses of the thymus of the mice, to antitumour agents (5-Fluorouracil or mitomycin C). Healthy adult mice weighing 25 gm each were divided into normal and experimental groups. 5-Fluorouracil (60 mg/kg) or Mitomycin-C $(400{\mu}g/kg)$ were injected subcutaneously to the animals every other day. Animals were sacrificed at 4 days and 7 days following the first injection. Pieces of the tissue taken from the thymus were prefixed with 2.5% paraformaldehyde-l.5% glutaraldehyde, followed by post-fixation with 1% osmium tetroxide. Ultrathin sections stained with uranyl acetate and lead citrate were observed with a JEM 100 CX-II electron microscope. The observed results were as follow: 1. Apoptoses of T-lymphocytes were observed more frequently in the thymus of the experimental groups than in those of a normal group. 2. In the experimental group, the plasma cells with distended cisternae of the granular endoplasmic reticulum and the eosinophile leukocytes were observed frequently. 3. In the experimental group, newly forming Hassall's corpurscles were observed frequently. 4. In the mitomycin-treated group, the epithelial reticular cells containing distended perinuclear cisternae, distended the granular endoplasmic reticula and pyknotic nuclei were observed in the cortico-medullary junctional area. 5. In the mitomycin-treated group, nuclear bodies with medium electron dense materials were often observed in the T lymphocyte. 6. In the 5-fluorouracil-treated groups, fused and dissolved tonofilament bundles and apoptotic bodies were observed in the some epithelial reticular cells in the medullary area. 7. In the 5-fluorouracil-treated groups, some elongated and bar-shaped lysosomes with electron lucent gap were often observed in the macrophages. 8. In the 5-fluorouracil-treated group, membrane complex of the smooth endoplasmic reticulum were ofen observed in the macrophage. From the above results, it was suggested that 5-fluorouracil or mitomycin could induce rapid involution of the thymus, and disturb maturation and differentiation of T lymphocytes, and, in turn, supress immunity.

• Proceedings of the KSMRM Conference
• /
• 2002.11a
• /
• pp.50-56
• /
• 2002

최근 3-4년간 MR의 hardware와 software의 급격한 발전으로 마침내 작년 말에 3.0 Tesla whole body MR 장비가 미국 FDA의 공인을 받았다. 한국에서도 일찍부터 3T MR장비의 개발이 이루어 졌고 이미 설치되어 연구와 임상이 이용되고 있다. 여러 회사에서 개발 및 연구된 전신 3.0T MR 장비가 여러가지 가능성을 보이고 임상 도입 단계에 있지만 아직까지 실지 임상에서는 뇌신경계 분야가 주류를 이루고 있다. 지금 뇌신경계 분야에서 보편적으로 늘리 사용되고 있는 1.5T MR 장비는 모든 면에서 상당히 안정적으로 임상 및 연구에 이용되고 있다. 1-2년 전만 해도 3.0 T MR기기는 뇌신경계 영역에서도 임상적으로 늘리 사용되기에는 안정적인 면에서는 1.5T 기기에 비해서 떨어지는 것이 사실이었다. 그래서 주로 연구실 영역에서 많이 이용되고 있었다. 그러나 지금 본원에 설치 완료되어 임상에 적용한지 6개월 정도 이용한 예에서 보면 (about 2300 cases/6months) hardware, software적인 면에서 아직 조금의 불편함이 있지만 많은 부분이 충분히 인지되고 개선이 가능한 부분으로 거의 불편함이 사라질 것으로 기대되고 있고, 불편함을 넘을 수 있는 여러 가지 장점이 있다고 본다. 고자장 (>3.0 T) MRI의 매력은 자장에 비례적으로 SNR, spectral resolution이 높아지고, T1, BOLD등에 의한 대조도가 향상한다는 것이다. SNR의 증가는 temporal, spatial 분해능을 증가시키고, spectral resolution이 높아짐에 따라 MR spectroscopy상에서 주요 대사물질 이외 작은 대사물질에 관한 스펙트럼의 분석을 향상시킨다. 이처럼 고자장 MR은 근본적인 장점을 가지고 있고 이러한 장점이 고자장 MR 시대로 가야 할 이유을 모두 설명하고 있다고 생각된다.세포질등이 있으며, 이들중에서 lysosomes, peroxisomes, 그리고 미토콘드리아가 특정한 유전성 백질질환에 중요한 역할을 하는 것이 밝혀졌다. 이러한 질환들은 최소한 각 소기관에 의한 질환군으로 분류될 수 있다.SXR이 ER의 transactivation 효과를 약간 촉진한 반면 MDA-MB-231세포는 SXR을 제외한 CAR와 PPAR${\gamma}$에 의해 ER의 transactivation 효과가 약간 증가되는 경향을 보였다. 이러한 결과는 유방암세포에서는 CAR, SXR, PPAR${\gamma}$과 같은 xenobiotic nuclear receptor에 의한 ER transactivation 효과가 간암세포와는 다르게 나타나며, 유방암의 종류에 따라서 endogenous CAR, SXR, PPAR${\gamma}$수용체가 다르게 발현됨으로써 이들에 대한 반응이 서로 상이한 특징을 나타낼 수 있을 것으로 사료된다. 따라서 estrogen receptor에 의해 매개되는 estrogn의 전사활성조절기전이 표적세포에 따라 다른 경로를 포함 할 수 있음을 시사한다.서 흡착 능력이 우수하게 나타났으며, 황화수소는 펄라이트, 왕겨, 소나무수피에서 상대적으로 우수한 것으로 나타났으며, 혼합충전재는 암모니아의 경우 코코넛과 펄라이트의 비율이 7：3인 혼합 재료 3번과 소나무수피와 펄라이트의 비율이 7：3인 혼합 재료 6번에서 다른 혼합 재료에 비하여 우수한 것으로 나타났다. 4. 코코넛과 소나무수피의 경우 암모니아 가스에 대한 흡착 능력은 거의 비슷한 것으로 사료되며, 코코넛의 경우 전량을 수입에 의존하고 있다는 점에서 국내 조달이 용이하며, 구입 비용도 적게 소요되는 소나무수피를 사용하는 것이 경제적이라고 사료된다. 5. 마지막으로 악취제거 미생물균주를 접종한 소나무수피 50%와 펄라이트

• The Korean Journal of Zoology
• /
• v.18 no.2
• /
• pp.87-101
• /
• 1975

Electron microscopic studies on the ultrastructure of the mouse oocyte were made to investigate the inhibition of germinal vesicle breakdown by dibutyryl cAMP. The nuclear membrane of the dibutyryl cAMP-treated oocyte is characterized by a decreased degree of folding, maintains the normal double membrane structure, and shows an increased occurrence of the nuclear pore. It is suggested that these may be related to the suppression of the maturation of oocytes at the germinal vesicle. Mitochondria in the control cell were shown to be spread evenly throughout the cytoplasm and structurally underdeveloped or transitionary having little cristae development. On the contrary, mitochondria in the treated oocyte were found to be localized mainly around the nucleus and to show a greater extent of cristae development. The oocyte treated with dibutyryl cAMP appears to have fewer and structurally simpler lysosomes as compared to the control. The Golgi complex in the control oocyte exhibits the typical granular and lamellar structure, whereas that in the treated cell is poorly developed. Many multivesicular bodies, tonofilaments, and free ribosomes were observed in the control as well as in treated cells. The microvilli become structurally irregular, and a development of the perivitelline space is apparent in the treated oocyte. It is concluded that there is no basic difference in the ultrastructure between the oocytes treated with dibutyryl cAMP for 24 hours in the medium and those collected directly from the follicle. However, the finding that dibutyryl cAMP induces a development of more pores along the nuclear membrane strongly suggests the possibility that this compound inhibits the maturation of oocytes by influencing the permeability of the nuclear membrane.