• Applied Microscopy
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• v.27 no.1
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• pp.31-46
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• 1997

Ultrastructure of mouse thymus was evaluated, following the administration of potassium dichromate and mercuric chloride, the heavy metals of evironmental pollutants. Potassium dichromate (20 mg/kg) or mercuric chloride solutions (10 mg/kg) were subcutanously injected to the mice. Six hours, three days and two weeks after the injections, animals were sacrificed. Thymic tissues were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde solutions. The procedure was followed by the fixation in 1% osmium tetroxide solutions. Washed and dehydrated tissue-blocks were embedded in the araldite mixture. Ultra-thin sections were stained with uranyl acetate-lead citrate solutions. Results observed were as follows: 1. In electron microscopy, cortical population of thymocytes in the thymus of experimental groups were reduced. especially in the outer cortex. Subcapsular cortices of potassium dichromate treated mice were filled with many epithelial reticular cells, whereas the similar area of mercuric chloride-treated mice exhibited large intercellular spaces. 2. In the thymus of mercuric chloride treated group, large intercellular spaces were formed by shrinkage of epithelial reticular cells, and the space was invaded by numerous cytoplasmic projections of macrophages. Thymocytes nuded out from the shrunken cytoplasm of epithelial reticular cells, presented numerous microvilli. 3. In the thymus of potassium dicromate treated group, many activated macrophages and plasma cells migrated into thymic cortices. 4. In the perivascular spaces of thymic cortices of potassium dichromate- and mercuric chloride-treated mice, activated macrophages. plasma cells, collagen fibrils, and flocculent substance of exudated materials were exhibited. From the above findifgs, it was concluded that potassium dichromate or mercuric chloride could disturb the normal differentiation or 'education' of T cells in the thymic cortex. In turn, these heavy metals may hurt the immunological defense mechanism.

• Applied Microscopy
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• v.25 no.1
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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.

• Applied Microscopy
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• v.1 no.1
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• pp.35-42
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• 1969

가토간장에서 채취(採取)한 간(肝)디스토마 성충(成蟲)의 정소(精巢)와 수정낭(受精囊)을 1.25% glutaraldehyde와 1% 사산화(四酸化) 오스뮴산(酸)으로 냉실(冷室)에서 이중고정(二重固定)하였다. 고정(固定)된 시료(試料)는 양식(樣式)에 따라 탈수(脫水)한 후(後) Epon-812로 포매(包埋)하여 MT-2형(型) Porter Blum microtome으로서 초박절편(超薄切片)을 만들어 수사화연(水酸化鉛)과 초산(醋酸)우라닐로서 이중염색(二重染色)한후 Hitachi HS-7형(型)과 HU-11E형(型)의 전자현미경(電子顯微鏡)으로 관찰(觀察)하였다. 관찰결과 간(肝)디스토마의 정세포(精細胞)는 타원형으로 난형(卵形)의 인(仁)을 포함(包含)한 큰 핵(核)을 갖고 있으며 핵(核)을 둘러싼 비교적소량(比較的小量)의 세포질(細胞質)에는 낭형(囊形)의 조면소포체(粗面小胞體)가 희소(稀少)하게 있으며 유리(遊離)리보좀 및 즐(櫛)을 가진 미토콘드리아, 중심체(中心體), 층판상(層板狀)의 골지체가 있다. 정자(精子)는 긴 원주형(圓柱形)의 핵(核)과 선단(先端)에 첨체(尖體)를 포함(包含)한 두부(頭部)와 중종편(中終片), 미부(尾部)의 말단부(末端部)로 갈수록 점차 가늘어져서 결국(結局) 편모(鞭毛)로 끝난다. 두부(頭部)의 선단부(先端部) 가까이 핵환(核環)이 있으므로 이를 기시점(起始點)으로 직경(直徑) $250{\AA}$ 정도의 $8{\sim}10$개(個)의 미세소관(微細小管)이 축사(軸絲)의 배면(背面) 원형질막(原形質膜) 직내면(直內面)의 외형질(外形質)에 평행(平行)하게 중종편(中終片)까지 신장(伸長)되어 있다. 미토콘드리아는 융합(融合)되어 두부(頭部)의 후반부(後半部) 핵(核)의 복측(腹側)에 평행(平行)하게 축사(軸絲)를 감싸는 원추형(圓錐形)으로 종단면(縱斷面)에서 반점상(班點狀)의 횡문(橫紋)이 관찰(觀察)되었다. 중심체(中心體)에서 기원(起原)된 축사(軸絲)는 중심부(中心部)에 중심섬유(中心纖維)와 중심초 및 이중(二重)의 미세소관(微細小管)이 9개(個) 둘러싸고 있는 구조(構造)를 하고 있다.

• Applied Microscopy
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• v.22 no.2
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• pp.30-45
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• 1992

An experimental study on the acute irradiation effects on the substantia nigra of head-irradiated rats were carried out. Rats anesthetized with sodium thiopental, were exposed only on their head areas with a single dose of 3,000 rads or 6,000 rads, respectively. Radiation was produced by Mitsubishi linear accelerator at the speed of 200 rads/min. Aminals were sacrificed on 6 hours, 2 days and 6 days following irradiations. By the perfusion fixation through the heart, rats were fixed with 1% glutaraldehyde-1% paraformaldehyde solution. Two hours later, brains were exposed and immersed in the same fixatives over night. Tissue blocks from subtantia nigra were punched out, and they were refixed in the 2% osmium tetroxide solution. Blocks were dehydrated through alcohol series, and embedded in the araldite mixture. Ultrathin sections were stained with uranyl acetate and lead citrate solutions, From the ultrastructural study, following results were made: 1. Six hours after irradiation, severe depletion of synaptic vesicles was occurred in the many axon terminals of the nigral neuropil. 2. Dramatical decrease of lysosomes and dense granules was observed. 3. Two days following irradiation, alterations of ribosomes, granular endoplasmic reticula, mitochondria, etc, were noticed. 4. Many of the malformations were seen to be repaired on the 6th day. 5. Above results were interpreted as follows. At the acute stage of heavy irradiation, neurotransmitters in the substantia nigra are released severely. But they are recovered within 6 days. It is concluded that acute head-irradiation may result severe disturbance of nigral motor control function during the first few days.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.7-17
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• 1982

The purpose of this study was to investigate the fine structural modifications of fibroblasts in the coronal region of inflamed human pulps from carious teeth. Six untreated human teeth with large carious lesions and two normal teeth as control were selected from male and female patients between the ages of 20 and 39. The teeth were divided into 4 groups by light microscopic findings: the normal control group, the chronic inflammatory cell-appeared group, the acute and chronic inflammatory cell-appeared group, and the total necrosis group. All tissues were fixed in 2.5% glutaraldehyde in 0.1M sodium cacodylate buffer at pH 7.4 and 1% osmic acid in same buffer. They were embedded in Epon 812. The ultrathin sections were stained conventionally and examined with a AEI Corynth 500 electron microscope. The results were as follows; 1. The fibroblasts of the normal pulps were almost in a quiescent state. 2. The active and the quiescent fibroblasts were found in the pulps of the chronic inflammatory cell-appeared group. Lymphocytes and plasma cells were also seen scattered among these fibroblasts. 3. In the pulps of the acute and chronic inflammatory cell-appeared group, active, degenerative and necrotic fibroblasts were found in the PMN appeared area. And all the fibroblasts in the fibrosis area were active. In the area of chronic inflammatory cellular infiltration, almost all the fibroblasts were active, but seldom were quiescent fibroblasts observed. Some fibroblasts in the pulps of two teeth had large vacuoles that contained banded collagen fibrils. The phagosomes had small beaded vesicles or large lysosome-like varicosity. In two of the teeth, microorganisms were present and two morphological shapes were identified, a rod and a coccus. 4. Vacuolar, vesicular, lamellar, fibrous and myelin structures were observed in the pulp of the total necrosis group, and cocci were also seen.

• Applied Microscopy
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• v.26 no.4
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• pp.431-446
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• 1996

This experiment was performed to study the ultrastructural changes of the juxtaglomerular cell of mice following subcutaneous injection of heavy metallic agents. Male mice were divided into normal and experimental groups. The mice were subcutaneouly injected with $HgCl_2$ (2mg, 5mg or 10 mg/Kg/BW) or with $K_{2}Cr_{2}O_7$(5 mg, 10 mg or 20 mg/Kg/BW). Mice were sacrificed on 6 hours, 3 days and 14 days after the injection. Kidneys were fixed in the 2.5% glutaraldehyde-1.5% paraformaldehyde solution, followed by refixation in the 1% osmium tetroxide solution. Dehydrated blocks were embedded in araldite mixture. The sections were cut on a LKB-V ultratome, and ultrathin sections stained with uranyl acetate and lead citrate were observed with JEM 100CX II electron microscope. The results were as follow: 1. Juxtaglomerular cell of the experimental groups showed some alterations, especially in the structures of protein synthesis including dilations and degradations of granular endoplasmic reticula, atrophy of Golgi complex, and numerous free ribosomes in the cytoplasm. 2. Juxtaglomerular cells treated groups showed a number of vacuoles, protogranules and some myelin figures in the cytoplasm, especially in the earlier groups. 3. Juxtaglomerular cells of treated groups, contained a large number of secretory granules showing variable electron densities and pleomorphism in later groups (2 weeks). From the above results, it was concluded that, the mercuric chloride or potassium bichromate induces acute renin release from juxtaglomerular cells of the mice, but many juxtaglomerular cells may secrete prematured secretory granules, or the synthetic system of the cell can not perform normal function.

• KSBB Journal
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• v.8 no.4
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• pp.313-319
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• 1993

Methyl fructoside was synthesized from sucrose and methanol using an immobilized invertase. The enzyme was covalently bound by glutaraldehyde on porous silica coated with polyethyleneimine to give loading capacity of 120mg of invertase per one gram of dry porous silica and effective activity of 100U per one milligram of bound invertase. Polyethyleneimine coating imparted a hydrophillic character, good activity retention and high loading capacity to the surface of porous silica as well as hydrophillic microenviroment in the vicinity of bound invertase. The immobilized enzyme was formed into an alginate-enclosed silica bead to have enough activity for methyl fructoside synthesis from aqueous methanol-sucrose solution. Using the alginate-enclosed biocatalyst the yield of methyl fructoside was obtained as high as 55.9% from aqueous 30% (v/v) methanol and 0.291mo1/l sucrose with 2U/ml activity at $25^{\circ}C$, pH 4.8.

• Bulletin of the Korean Chemical Society
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• v.28 no.5
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• pp.783-790
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• 2007

The immobilization of proteins and their molecular interactions on various polymer-modified glass substrates [i.e. 3-aminopropyltriethoxysilane (APTS), 3-glycidoxypropyltrimethoxysilane (GPTS), poly (ethylene glycol) diacrylate (PEG-DA), chitosan (CHI), glutaraldehyde (GA), 3-(trichlorosilyl)propyl methacrylate (TPM), 3'-mercaptopropyltrimethoxysilane (MPTMS), glycidyl methacrylate (GMA) and poly-l-lysine (PL).] for potential applications in a nanoarray protein chip at the single-molecule level was evaluated using prismtype dual-color total internal reflection fluorescence microscopy (dual-color TIRFM). A dual-color TIRF microscope, which contained two individual laser beams and a single high-sensitivity camera, was used for the rapid and simultaneous dual-color detection of the interactions and colocalization of different proteins labeled with different fluorescent dyes such as Alexa Fluor® 488, Qdot® 525 and Alexa Fluor® 633. Most of the polymer-modified glass substrates showed good stability and a relative high signal-to-noise (S/N) ratio over a 40-day period after making the substrates. The GPTS/CHI/GA-modified glass substrate showed a 13.5-56.3% higher relative S/N ratio than the other substrates. 1% Top-Block in 10 mM phosphate buffered saline (pH 7.4) showed a 99.2% increase in the blocking effect of non-specific adsorption. These results show that dual-color TIRFM is a powerful methodology for detecting proteins at the single-molecule level with potential applications in nanoarray chips or nano-biosensors.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.1
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• pp.51-58
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• 1998

본 연구는 체외수정 프로그램에 참여하는 환자에 있어서 난자회수 이틀째의 자궁내막의 발달상태를 알아보기 위하여 pinopode의 발달상태, 에스트로젠 및 프로제스테론 수용체의 발현을 관찰하였다. 생검한 자궁내 막 조직 을 양분하여, 절반은 전사전자 현미경 (scanning electron microscope)으로 pinopode를 관찰하기 위하여 2.5% glutaraldehyde와 2% paraformaldehyde로 고정하였고, 나머지 절반은 dating 및 스테로이드 수용체의 면역조직화학적 측정 (immunocytochemistry)을 위하여 10% formalin으로 고정하였다. 모두 12명의 환자중 8명에서 pinopode가 관찰되었으며, pinopode 발달이 관찰되지 않은 환자들은 hCG 주사를 맞는 날의 estradiol (E2)의 혈중농도가 600 pg/mL이하로 낮았다. 본 연구의 결과로부터 자궁내막의 발달상태를 알아보기 위해서는 지금까지 일반적으로 사용되어 오던 dating이나 스테로이드 수용체의 면역조직화학적 측정법 이외에도 pinopode를 관찰함으로써 조금 더 정확한 진단을 할 수 있으리라고 사료되며, pinopode의 발달은 E2의 혈중농도와 관계가 있을 것으로 추정된다.

• Journal of Life Science
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• v.21 no.1
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• pp.127-133
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• 2011

${\beta}$-Galactosidase was immobilized on chitosan bead by covalent bonding using glutaraldehyde. The characteristics of the immobilized enzyme were investigated. Maximum immobilization yield of 75% was obtained on chitosan bead. Optimum pH and temperature for the immobilized enzyme was 7.0 and $50^{\circ}C$, respectively. The immobilized enzyme showed a broader range of pH and temperature compared to a free one. A mathematical model for the operation of the immobilized enzyme in a packed-bed reactor was established and solved numerically. Under different inlet lactose concentrations and feed flow rate conditions, lactose conversion was measured in a packed-bed reactor. The experimental results of continuous operation in a packed-bed reactor were compared to theoretic results using Michaelis-Menten kinetics with competitive product inhibition and external mass transfer resistance. The model predicted the experimental data with errors less than 5%. Process optimization of continuous operation in a packed-bed reactor was also conducted. In a recirculation packed-bed operation, conversion of lactose was 97% in 3 hours. In a continuous packed-bed operation, the effect of flow rate and initial lactose concentration was investigated. Increasing flow rates and initial lactose concentration decreased the conversion of substrate.