• Molecules and Cells
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• 제26권4호
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• pp.356-361
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• 2008

In this work, we have studied the structural and functional linkage between lamin A/C, nuclear actin, and organization of chromosome territories (CTs) in mammary carcinoma MCF-7 cells. Selective down-regulation of lamin A/C expression led to disruption of the lamin A/C perinuclear layer and disorganization of lamin-bound emerin complexes at the inner nuclear membrane. The silencing of lamin A/C expression resulted in a decrease in the volume and surface area of chromosome territories, especially in chromosomes with high heterochromatin content. Inhibition of actin polymerization led to relaxation of the structure of chromosome territories, and an increase in the volumes and surface areas of the chromosome territories of human chromosomes 1, 2 and 13. The results show an important role of polymeric actin in the organization of the nuclei and the chromosome territories.

• 치과방사선
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• 제17권1호
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• pp.7-20
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• 1987

The author studied the acute reaction of cobalt-60 irradiation to buccal mucosa in rats and difference of the effects of single versus fractionated exposure. 195 Sprague Dowley strain rats, weighing about 120gm, were used in this experiment. 3 rats served as controls and the remaining 192 rats were divided into six groups of 32 rats each. Experimental group Ⅰ, Ⅱ, Ⅲ were received a single dose of 15Gy, 16.5Gy, 18Gy and group Ⅳ, Ⅴ, Ⅵ were received two equal sized fractionated dose of 9Gy, 9.75Gy, 10.5Gy at 4 hour intervals, respectively. The experimental groups were irradiated with cobalt-60 teletherapy unit, Picker model 4M 60 (Field size, 12x5 cm, SSD, 50㎝, Dose rate, 222cGy/min, Depth, 1㎝). The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and the changes of the irradiated buccal mucosa were observed by electron and light microscopy. The results were as follows: 1. A single exposure was more damaging than fractionated exposure, and as the radiation dose increased, the changes of cell organelles became faster, but the healing of radiation-induced damage in fractionated exposure was faster than in single exposure. 2. The radiation-induced changes of the basal cells were the most prominent in 18Gy-single exposure group, and the least in 18Gy-fractionated exposure group. 3. Electron-microscopically, there appeared nuclear changes, swelling of mitochondria and rough endoplasmic reticulum, decrease of free ribosome, presence of vesicles, widening of intercellular space, and loss of basal lamina. The early remarkable changes were partly loss of nuclear membrane and swelling of mitochondria. 4. Light-microscopically, derangement and pyknosis of basal cells, hydropic changes of spinous cells, enlargement of granular cells, indistinctness of basement membrane, and proliferation of epithelium were observed.

• 콘크리트학회논문집
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• 제22권6호
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• pp.817-824
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• 2010

약 콘크리트 격납구조물은 구조적 안전성이 뛰어나고 경제적이므로 원자력발전소 격납건물, LNG 저장탱크 등에 널리 사용되고 있다. 격납구조물 중 지붕 돔의 형태는 구조적 안전성, 물량 및 시공 난이도에 큰 영향을 미치므로 최적의 두께와 곡률을 도출하고자 하는 노력이 필요하다. 한편 일반적으로 PSC 구조로 설계되는 링빔은 이러한 돔을 지지하여 벽체의 변형을 최소화시키는 역할을 하며, 단면 크기와 더불어 프리스트레스 수준을 적절히 결정하는 것이 설계의 핵심이 된다. 이 연구에서는 축대칭 회전쉘의 막이론을 적용하여 본설계 시의 유한요소해석에 앞서 돔과 링빔의 초기 형상이나 프리스트레스 수준을 효율적으로 결정할 수 있는 기법을 제안하였다. 이러한 기법을 국내에서 시공된 격납구조물의 돔과 링빔에 적용하여 분석하고 단면 형상이나 프리스트레싱 설계에 대한 개선 방안을 고찰하였다.

• 대한임상검사과학회지
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• 제39권2호
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• pp.122-127
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• 2007

This study is a report about a specific patient whose primary stomach adenocarcinoma metastasized to uterine cervix adenocarcinoma. A thirty-nine year old female patient was initially diagnosed as having metastatic adenocarcinoma in the supraclavicular lymph node. Upon further examination, she was diagnosed with stomach adenocarcinoma. 8 months later, a cervix punch biopsy was performed. The stains used for examination were H&E stain, PAS stain, Alcian blue stain, Mucicarmine stain, Papanicolaou's (Pap.) stain, and as immunohistochemical stains, cytokeratin 7 and 20 were done. In the H&E stain, the tumor cells showed prominent and eccentric nuclei, thin nuclear membrane in abundant mucous cytoplasm, and cylinder shape. In the PAS stain, intracytoplasmic mucin vacuoles were stained with pink, and in Alcian blue and Mucicarmine stains, intracytoplasmic mucin vacuoles were stained with blue and red. As in the above results, she was diagnosed with undifferentiated adenocarcinoma. As found on the cytologic smear preparation of the uterine cervix stained by Papanicolaou's stains, the background was relatively clear, the number of malignant cells was relatively low, and large and eccentric nuclei in abundant cytoplasm were observed. Upon observing the tissue preparation of the uterine cervix biopsy by H&E stain, a clear background, large and eccentric nuclei, and a signet ring cell types were observed, and the number of malignant cells were fewer than in the primary uterine cervix adenocarcinoma. The vacuoles in cytoplasm were observed. The nuclear membrane and chromatin were thick and very rough, and upon observation by cytokeratin 7 and 20 of immunohistochemical stain, the tumor cells indicated a positive rate of 70% and 20%, respectively. According to these results, also she was diagnosed with metastasized uterine cervix adenocarcinoma. In summary of the results of pathologic findings on stomach biopsy and cytologic, histopathologic, and immunohistochemical finding on uterine cervix biopsy, the adenocarcinoma of her uterine cervix could assert the adenocarcinoma of signet ring cell type that was metastasized from the primary undifferentiated adenocarcinoma in stomach.

• 한국잠사곤충학회지
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• 제32권1호
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• pp.49-57
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• 1990

가잠 다각체병 바이러스의 감염경로를 연구하기 위해서 2령 기잠에 바이러스를 접종하고 6, 12, 24, 48시간의 감염조직을 전자현미경 관찰한 결과는 다음과 같다. 1. 다각체단백질이 중장소화액에 의해 용해되어져 바이러스입자가 유리되고 섬모융모표면에서 부터 흡착되는 것이 관찰되었다. 2. 다각체 접종 후 24시간에 이미 중장원통세포핵에 현저한 증식상을 보였으며 중장피막세포 간극에서 envelope을 획득한 바이러스입자가 관찰되었다. 3. 기저막 가까이 있는 원통세포의 세포질에서 envelope을 획득한 바이러스입자들이 다수 관찰되었으며, envelope을 가지고 있지 않은 바이러스는 관찰되지 않았다. 기저막을 통과한 바이러스입자는 체강쪽으로 이행되어져 혈구세포에 집적되고 있다. 4. 접종후 48시간에 중장피막 가까이에 분포하고 있는 혈구세포 및 기관피막세포핵에서 NPV의 전형적인 증식상이 관찰되었다.

• Applied Microscopy
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• 제31권3호
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• pp.223-233
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• 2001

우리나라 서해안에서 채집된 서해낙지(Octopus minor)의 정자 완성과정을 전자현미경을 통해 관찰한 결과 다음과 같았다. 서해낙지의 정자 완성 과정은 초기 중기 후기 정세포 그리고 성숙정자 등 4단계로 나눌 수 있었다. 초기 정세포는 구형의 세포로서 전자밀도가 낮아 밝게 보였으며 핵의 상단부 골지체로부터 형성된 첨체는 전자밀도가 높아서 어둡게 관찰되었다. 핵의 하단 근위 중심소체에서 유도된 것으로 보이는 extra-nuclear rod(enr)는 처음에는 구형에서 타원형으로 변모되면서 핵의 상단부위까지 신장되었으며, 원위중심소체로부터는 축삭이 형성되는 모습도 관찰되었다. 핵막 주위에서 많은 수의 미세소관으로 형성된 만췌트(manchette)도 관찰되었다. 중기 정세포는 핵내 염색질이 가는 실모양으로 응축 되었고, 이 시기에서도 만췌트가 핵막의 주위에서 관찰되었다. 특히 구형의 첨체는 긴 타원형으로 변모되면서 많은 수의 가로무늬를 형성하였고 전자밀도는 중등도로 나타났다. 후기 정세포는 핵내 염색질이 굵고 짧게 응축되었고, 중편에서는 미토콘드리아가 축삭을 감싸고 있는 mitochondrial sleeve를 형성하였다. 축삭은 전형적인 9+2 구조를 보였으며 축삭 주위에서는 9개의 금은 섬유(coarse fibres)도 관찰되었다. 성숙정자의 첨체 내강에서도 가로무늬가 관찰되었는데 특이하게도 가로무늬 사이에서 일정한 간격의 돌기물들이 관찰되었다. 성숙정자의 전체 길이는 약 $390{\mu}m$였으며 첨체는 나선형으로 꼬여 있었으나 머리부위는 꼬여 있지 않고 바나나 모양으로 약간 휘어져 있었다. 또한 정자의 중편에는 $11\sim12$개의 미토콘드리아가 굵은 섬유들을 둘러싸고 있었으며, 이 금은 섬유들은 꼬리의 주편 (main piece)까지만 연결되고 단편 (end piece)에서는 9+2구조의 축삭만이 관찰되었다.

• Nuclear Medicine and Molecular Imaging
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• 제41권5호
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• pp.343-349
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• 2007

방사성옥소는 갑상선암의 핵의학적 영상과 방사성치료에 널리 그리고 성공적으로 사용되어 왔다. 최근 세포의 옥소섭취를 담당하는 운반체로서 Na/I symporter (NIS)의 분자세포학적 특성이 규명되고 그 유전자가 클로닝되면서 앞으로는 갑상선암 이외의 각종 암에도 NIS 유전자를 외부에서 전달함으로써 방사성옥소 치료를 적용하는 새로운 암치료 기술이 가능할 것으로 기대되고 있다. 방사성옥소를 이용한 암치료의 성공을 위해서는 NIS를 통한 표적세포의 옥소 섭취를 극대화 시키는 것이 핵심이다. TSH는 갑상선 세포의 NIS 발현을 항진시키고 retinoic acid는 갑상선암과 유방암 세포의 NIS발현을 증가시키는 효과가 있다. 또 일반 암세포에는 NIS 유전자를 전달하여 발현 시킬 수 있다. 그러나 NIS 발현 만으로는 원하는 수준의 방사성옥소 섭취를 충분히 얻지 못할 수 있다. 이는 세포의 옥소 섭취가 NIS 단백질의 총량이 아니라 세포막에 위치한 NIS의 양에 의해 결정되기 때문이다. 즉, 옥소를 섭취하려는 전사된 NIS단백질이 세포막으로 이동하여 정상적으로 기능하게 하는 조절 기전이 중요하다. NIS의 세포막 이동 기전은 아직 밝혀져 있지 않으나 다른 운반체와 유사하게 단백질의 전사후 glycosylation이나 phosphorylation이 관여할 것으로 생각된다. 본 연구진은 NIS 유전자를 전달한 암세포에서epidermal growth factor를 통한 extracellular signal regulated kinase 신호경로의 활성화가 방사성옥소 섭취를 항진시킴을 관찰하여 NIS의 전사외 기능조절 기전을 조사하고 있다. 앞으로 NIS기능에 대한 조절기전이 보다 자세하게 밝혀지면 방사성옥소 치료기술과 NIS유전자 영상기술의 개선과 발전에 도움이 될 것으로 기대된다.

• The Korean Journal of Physiology and Pharmacology
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• 제10권3호
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• pp.131-135
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• 2006

Coeruleo-vestibular pathway which connects locus coeruleus and vestibular nuclei is noradrenergic. This study was designed to elucidate the effects of phenylephrine on the spontaneous activity of acutely isolated medial vestibular nuclear neurons of rat by whole-cell patch-clamp technique. Sprague-Dawley rats, aged 14 to 16 days, were used. After enzymatic digestion, dissociated medial vestibular neurons were transferred to a recording chamber mounted on an inverted microscope, and spontaneous action potentials were recorded by standard patch-clamp techniques. In current-clamp mode, the frequency of spontaneous action potential of medial vestibular nuclear neurons was decreased by phenylephrine (n=15). Phenylephrine increased the amplitude of afterhyperpolarization without changes in the resting membrane potential and spike width. In voltage-clamp mode, the whole potassium currents of the medial vestibular nuclear neurons were increased by phenylephrine (n=12). These experimental results suggest that ${\alpha}-receptor$ mediates the inhibitory effects on the neuronal activity of the medial vestibular nuclear neuron.

• Molecules and Cells
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• 제38권5호
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• pp.402-408
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• 2015

Protein O-GlcNAcylation, dictated by cellular UDP-N-acetylglucosamine (UDP-GlcNAc) levels, plays a crucial role in posttranslational modifications. The enzyme GlcNAc kinase (NAGK, E.C. 2.7.1.59) catalyzes the formation of GlcNAc-6-phosphate, which is a major substrate for the biosynthesis of UDP-GlcNAc. Recent studies have revealed the expression of NAGK in different types of cells especially in neuronal dendrites. Here, by immunocytochemistry (ICC) and immunonucleochemistry (INC) of cultured rat hippocampal neurons, HEK293T and GT1-7 cells, we have showed that NAGK immuno-reactive punctae being present in the nucleoplasm colocalized with small nuclear ribonucleoprotein-associated protein N (snRNPN) and p54NRB, which are speckle and paraspeckle markers, respectively. Furthermore, NAGK IR cluster was also found to be colocalized with GTF2H5 (general transcription factor IIH, polypeptide 5) immuno reactive punctae. In addition, relative localization to the ring of nuclear lamin matrix and to GlcNAc, which is highly enriched in nuclear pore complexes, showed that NAGK surrounds the nucleus at the cytoplasmic face of the nuclear outer membrane. By in situ proximity ligation assay (PLA) we confirmed the colocalization of NAGK with snRNPN in the nucleus and in dendrites, while we also verified the interactions of NAGK with p54NRB, and with GTF2H5 in the nucleus. These associations between NAGK with speckle, paraspeckle and general transcription factor suggest its regulatory roles in gene expression.

• The Korean Journal of Physiology and Pharmacology
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• 제23권6호
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• pp.539-547
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• 2019

Anoctamin 5 (ANO5)/TMEM16E belongs to a member of the ANO/TMEM16 family member of anion channels. However, it is a matter of debate whether ANO5 functions as a genuine plasma membrane chloride channel. It has been recognized that mutations in the ANO5 gene cause many skeletal muscle diseases such as limb girdle muscular dystrophy type 2L (LGMD2L) and Miyoshi muscular dystrophy type 3 (MMD3) in human. However, the molecular mechanisms of the skeletal myopathies caused by ANO5 defects are poorly understood. To understand the role of ANO5 in skeletal muscle development and function, we silenced the ANO5 gene in C2C12 myoblasts and evaluated whether it impairs myogenesis and myotube function. ANO5 knockdown (ANO5-KD) by shRNA resulted in clustered or aggregated nuclei at the body of myotubes without affecting differentiation or myotube formation. Nuclear positioning defect of ANO5-KD myotubes was accompanied with reduced expression of Kif5b protein, a kinesin-related motor protein that controls nuclear transport during myogenesis. ANO5-KD impaired depolarization-induced $[Ca2^{+}]_i$ transient and reduced sarcoplasmic reticulum (SR) $Ca^{2+}$ storage. ANO5-KD resulted in reduced protein expression of the dihydropyridine receptor (DHPR) and SR $Ca^{2+}-ATPase$ subtype 1. In addition, ANO5-KD compromised co-localization between DHPR and ryanodine receptor subtype 1. It is concluded that ANO5-KD causes nuclear positioning defect by reduction of Kif5b expression, and compromises $Ca^{2+}$ signaling by downregulating the expression of DHPR and SERCA proteins.