• Applied Microscopy
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• 제42권1호
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• pp.49-52
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• 2012

For TEM study of biological samples or polymers that are contained in organic structure, it is often required that the sample is prepared by using ultramicrotome and stained with proper agents to increase the contrast of organic structure. In this study, we investigated an efficient TEM sample preparation method for ductile heterogeneity material by using ultramicrotomy. Cryo-ultramicrotomy is a suitable method that is capable of rendering sample hardness for various ductile materials. However, it has several factors to consider, such as experimental cost, working time and finding the optimal staining conditions. To satisfy these considerations, we prepared TEM sample by using ultramicrotome without cryofunction, and secured the sample hardness by applying the staining process prior to ultrathin sectioning. The cross-linked polyethylene structure in the sample was stained with the 2% $RuO_4$ solution in a sealed test tube for 24 hours at $4^{\circ}C$. After the sample staining, ultrathin sections of sample were prepared using ultramicrotome. As a result, it was revealed that the difficulties associated with staining of ultrathin sections prepared by low-temperature conditions were improved. In addition, appropriate staining depth of sample could be selected for sectioning process. The quality of TEM sample obtained by using this method was better than that of cryo-ultramicroscopy. Finally, it is expected that our method could be effectively applied in TEM sample preparation for a variety of nano-bio convergence materials.

• Applied Microscopy
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• 제48권2호
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• pp.49-53
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• 2018

A successful transmission electron microscope (TEM) analysis is closely related to the preparation of the TEM specimen and should be followed by the suitable TEM specimen preparation depending on the purpose of analysis and the subject materials. In the case of the Si-based anode material, lithium atoms of formed Li silicide were removed due to ion beam and electron beam during TEM specimen preparation and TEM observation. To overcome the problem, we proposed a new technique to make a TEM specimen without the ion beam damage. In this study, two types of test specimens from the Si-based anode material of Li-ion battery were prepared by respectively adopting the only focused ion beam (FIB) method and the new FIB-ultramicrotome method. TEM analyses of two samples were conducted to compare the Ga ion damage of the test specimen.

• Applied Microscopy
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• 제46권4호
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• pp.171-175
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• 2016

A distinctive neuronal network in the brain is believed to make us unique individuals. Electron microscopy is a valuable tool for examining ultrastructural characteristics of neurons, synapses, and subcellular organelles. A recent technological breakthrough in volume electron microscopy allows large-scale circuit reconstruction of the nervous system with unprecedented detail. Serial-section electron microscopy-previously the domain of specialists-became automated with the advent of innovative systems such as the focused ion beam and serial block-face scanning electron microscopes and the automated tape-collecting ultramicrotome. Further advances in microscopic design and instrumentation are also available, which allow the reconstruction of unprecedentedly large volumes of brain tissue at high speed. The recent introduction of correlative light and electron microscopy will help to identify specific neural circuits associated with behavioral characteristics and revolutionize our understanding of how the brain works.

• 한국동물학회지
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• 제26권4호
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• pp.271-282
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• 1983

동면기 양서류 피부 색소세포의 미세구조를 관찰하기 위하여 무미 양서류인 개구리 (Rana nigromaculata)의 피부조직을 2.5% glutaradehyde-paraformaldehye (pH 7.2)와 2% osmium tetroxide에 전후 고정한 후 ethanol과 acetone으로 탈수, Epon 812 mixture에 포매하여 LKB ultramicrotome으로 초박절 표본을 만들어 uranyl acetate와 lead citrate로 염색하여 Jeol-100B형 전자현미경으로 관찰하여 다음과 같은 결과를 얻었다. 동면기 개구리의 피부 색소세포는 대황세포, iridophore 및 흑색소 보유세포로 구성되었으며, 이들 세포의 특징은 다음과 같다. 1. 대황세포 A. 대황세포는 pterinosome과 carotinoid vesicles이 전세포질에 채워져 있었으며, 많은 ribosome과 소수의 mitochondria 및 glycogen particle이 pterinosome 사이에 분산되었다. B. Pterinosome은 크고 작은 원형 또는 타원형이며, 이 소낭속의 내부 구조물에 EK라 6가지 형 (제1형 pterinosome, 제2형 pterinosome, 제3형 pterinosome, 제4형 pterinosome, 제5형 pterinosome, 제6형 pterinosome)으로 구분되며, 특히 제1형 pterinosome, 제2형 pterinosome, 제3형 pterinosome이 발달되었따. C. Carotinoid vesicle은 작은 원형 또는 타원형이며, 대부분의 carotinoid vesicle은 핵 주변부에 덩어리 모양으로 모여있고, 일부분은 이 세포의 pterinosome 사이에 분산되어 나타났다. 2. Iridophore A. Iridophore는 볼록렌즈와 같이 나타나고 좁은 세포간 공간에 의하여, 대황세포 아래에 위치하였다. B. Iridophore는 장방형 EH는 방추형의 reflective platelet로 채워져 있었으며, 서로 평행하게 규칙적으로 배열되었다. 3. 흑색소 보유세포 A. 흑색소 보유세포는 대황세포와 iridophore와 평행하여 가장 밑부분에 위치하였다. B. 흑색소 과립은 원형 또는 타원형으로 전세포질에 채워져 있었으며, 세포 소기관은 잘 관찰되지 않았다. C. 흑색소 과립으로 채워진 흑색소 보유세포의 돌기는 iridophore의 양 측부로 \ulcorner어 올라가 대황세포와 iridophore의 사이에 위치하였다.

• 한국동물학회지
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• 제22권3호
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• pp.103-114
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• 1979

양서류 피부과립선의 미세구조를 관찰하기 위하여 무미양서류인 무당개구리(Bombina orientalis), 두꺼비 (Bufo bufo gargarizans), 개구리 (Rana nigromaculata) 및 옴개구리 (Rana rugosa)의 피부조직은 2.5% glutaraldehyde-paraformaldehyde (pH 7.2)와 1%osmium tetroxide에 전후 고정한 후 ethanol과 acetone으로 탈수, Epon 812 mixture에 포매하여 LKB ultramicrotome으로 초박절표본을 만들어 uranyl acetate와 lead citrate으로 염색하여 JEOL-100B형 전자현미경으로 관찰하여 다음과 같은 결과를 얻었다. 1. 양서류 피부과립선은 선상피세포와 근상피세포로 이루어졌다. 2. 양서류 피부과립선의 선상피세포는 암세포들로 구성되었으나 무당개구리에서는 명세포도 관찰되었다. 3. 양서류 피부과립선은 전분지를 하였다. 4. 양서류 피부과립선 상피세포의 핵은 원형 내지 타원형으로 크고 작은 핵경함요를 보였고, heterochromatin은 주로 핵경 인접부에 많았다. 세포질에는 mitochondria가 핵주변부에 비교적 많이 산재하였고, rough-surfaced endoplasmic reticulum은 핵 주변부에 발달하였지만 smooth-surfaced endoplasmic reticulum은 미약하였다. 5. 분비과립들은 구형 또는 난형으로 높은 전자밀도를 보였으며 다소 약한 전자밀도를 보이는 과립도 관찰되었다. 6. 양서류 과립선내 분비과립들이 같은 세포내에서 다소 전자밀도의 차이를 보이는 것은 분비과립의 형성단계에 따른 농도 차이에 기인하며 그 화학적 조성은 유사하다고 생각된다.

• 한국동물학회지
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• 제21권1호
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• pp.29-39
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• 1978

양서류 피부 점액선의 선상피세포의 미세구조를 관찰하기 위하여 양서류 피부조직을 2.5% glutaraldehyde-paraformaldehyde(pH7.2) 1% osmium tetroxide에 전후 고정 한후 ethanol과 aceton으로 탈수, Epon 812에 포매 Sorvall MT-2B ultramicrotome으로 ultrathin section을 만들어 uranyl acetate와 lead citrate으로 염색하여 JEOL-100B형 전자현미경으로 관찰하여 다음과 같은 결과를 얻었다. 1. 양서류 피부 점액선은 선상피세포와 근상피세포로 이루어졌다. 2. 양서류 피부 점액선의 선상피세포는 미세구조적인 면에서 종에 따라 여러형의 세포들이 관찰되었다. a. 도롱뇽에서는 암세포와 명세포가 관찰되었다. b. 무당개구리에서는 mitochondria가 많은 세포와 원형의 분비과립을 갖는 세포들이 관찰되었다. c. 맹꽁이에서는 구형의 분비과립을 갖는 세포와 거품모양의 과립괴를 갖는 세포들이 관찰되었다. d. 개구리 피부 점액선은 A형과 B형점액선으로 구분되었고, A형점액선 상피에서는 mitochondria가 많은 세포와 원형의 분비과립을 갖는 세포, B형점액선 상피에서는 mitochondria가 많은 세포와 많은 분비과립을 갖는 세포 및 거의 전 세포질이 endoplasmic reticulum으로 채워진 세포들이 관찰되었다. 3. 위의 사실들로 미루어 양서류 피부점액선의 선상피는 mitochondria가 많은 미분화세포와 점액분비과립을 많이 함유한 성숙세포 및 전 세포질이 거의 rough endoplasmic reticulum으로 채워진 분비후기세포로 구성된다고 생각된다.

• 대한치과의사협회지
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• 제9권12호
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• pp.819-822
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• 1971

For this investigation, author isolated Streptococcus mitis strain SD-9 from the bacterial flora in the human dental plaque, which was incubated in brain-heart infusion media containing 5% sucrose at 37℃ for 24 hours. For the cytochemical demonstration of polysaccharide produced by this strain, a modified thiosemicarbazide osmium method (Critchley et al., 1967) was used. After fixation with this reagent, the harvested cells was suspended in 1% agar for the higher concentration of cells(Kellenberger et al., 1964). And they were dehydrated in the various concentration of ethanol, and embedded in Epon 812(Luft, 1961). Sectioning was done with the Sorvall MT-2 Porter Blum ultramicrotome by means of a glass knife, and the sections were stained with saturated uranyl acetate and lead citrate (Raynolds, 1963). All preparations were examined in a electron microscope, Hitachi HU-ll E-1 type. The morphological features of extracellular polysaccharide produced by Streptococcus mitis strain SD-9 were appeared in 3 structurally different forms, those are, electron dense fibrillar material linearly arranged adjacent to the outer surface of cell wall, highly electron dense globular material adjacent to the outer surface of cell wall, and strutureless fluffy meshwork of possible very fine filament.

• Parasites, Hosts and Diseases
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• 제22권1호
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• pp.30-36
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• 1984

An ultrastructural study on the mature spermatoBoa oi Cloptorchis sineitsis was carried out. For this study, the liver cukes were collected from the livers of rabbits and rats artificially infected with the metacercariae obtained from the fresh water fish, Pseudorasbora parve. Six-month old worms were used. The collected liver fiukes were washed with 0.85% saline solution and then immediately moved to cold 2% glutaraldehyde buffered with 0.1M Millonig's phosphate buffier (pH 7.4) . The materials were dissected into appropriate pieces in the fixative about 30 minutes after beginning of the fixation. Two hours later the materials containing the seminal receptacle were rinsed several times with the buffier and were secondarily fixed with cold, bugeyed 1% osmium tetroxide(OsO4) for 2 hours. The fully mixed tissue blocks Ivere dehydrated in a series of graded concentrations of acetone and were embedded in Epon 812 mixture. Thin sections obtained from LKB-5 ultramicrotome were stained with uranyl acetate and Reynold's lead citrate. Observations of the sections were carried out with JEM-100CX II electron microscope, In general, the mature sperm was long thread-like form with a sickle-shaped head. According to the longitudinal sectioned view of the sperm tail, the nucleus seemed to be spirally coiled and run a little far along the tail. The acrosome was not observed. The cytoplasm of the tail was biflagellated as usual in trematodes. Unlike other platyhelminth spermatozoa, the sperm tail of Clenorchis sinensis showed the ${\ulcorner}9+2{\lrcorner}$ in the microtubular arrangement. The mitochondria with poorly developed cristae were observed throughout the middle piece. The middle piece of the tail showed dull ladder or triangular shapes with the two flagella at the bottom. But, the principal piece of the tail was slightly flattened cylindrical shape with two aagella within the cytoplasm. The end piece was uniflagellated. It was not clearly identised whether the end piece was subdivided into two by aagellum or the lengths of the two aagella were different. The glycogen granules were rich in the cytoplasm throughout the lenght of the spermatozoa. These granules might be the energy source for the movement of the spermatosoa.

• 한국재료학회지
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• 제11권4호
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• pp.329-334
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• 2001

붕산용액에서 양극산화법으로 장벽형 산화피막을 형성시킨 후 미세조직을 관찰하였다. 양극산화시 인가되는 전압에 따른 피막의 성장속도는 1.54nm/v의 직선적인 관계를 나타냈으며 300v의 인가전압에서 생성된 산화피막의 조직은 50$0^{\circ}C$에서 열처리하였을 경우 피막의 상 전이가 일어나지 않았으나 높은 인가전압에서 생성된 산화피막의 경우는 피막의 조직이 비정질에서 ${\gamma}$-alumina로 변태되는 것이 관찰되었다. 또한 피막이 전자빔 조사에 의해서도 ${\gamma}$-alumina로 전이가 일어났다.

• 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.