• Applied Microscopy
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• 제25권3호
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• pp.1-19
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• 1995

The present study was performed to clarify the effect of vagus nerve stimulation on the enterochromaffin(EC) cells in the body of the stomach, the first part of the duodenum and the ceceum of rats by using routine electron microscopy and immunogold labelling. The changes in the ultrastructure and in the labelling density of the gold particles of the EC cells were investigated after vagus nerve stimulation. The vagus nerve was electrically stimulated with a square wave pulse generator for a duration of 5 minutes each, a total of 8 times at 2 minute intervals. Immunogold labelling demonstrated that the epithelial serotonin immunoreactive cells of the gastrointestinal tract are EC cells containing characteristic pleomorphic granules. Immunocytochemically labelled gold particles were largely concentrated in the dense matrix of the granules of the EC cell, and the labelling density of the gold particles considerably increased after the vagus nerve stimulation. Except for a slight activation of Golgi complexes, no remarkable changes in the ultrastructures of the EC cells were noted after the vagus nerve stimulation. The above results suggest that vagus nerve stimulation may activate serotonin biosynthesis in EC cells.

• Applied Microscopy
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• 제8권1호
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• pp.1-8
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• 1978

The aim of this research was to discover the action mechanism of various antituberculosis agents (isoniazid, paraaminosalicylic acid and streptomycin) which act on Mycobacteria tuberculosis hominis $H_{37}R_v$ and also to study the relationship of ultrastructural changes and the growth pattern in Mycobacterium tuberculosis hominis. The ultrastructural change was observed with an electron microscope while the growth pattern was studied through in vitro culture. The results are summarized as follows: 1. The ultrastructural changes found in the group treated only with isoniazid were the loss of nuclear materials and the appearence of electron dense granules. 2. In the group treated with paraaminosalicylic acid, thickening of nuclear filaments and meso some arrangement disorders were observed. 3. In the group treated with streptomycin, the ribosome particles appeared indistinct and the cytoplasm was denaturalized. 4. In the group cross treated with all three agents, all the ultrastructural changes mentioned above could be observed in the cell just as they appeared in the single treated groups. 5. In all of the single and in the crossly treated group, there were no significant changes note in the cell wall or cytoplasmic membranes of any of the cells observed. 6. In the cultural data in vitro, through the crossly treated group and single treated group. growth was observed in 3-5 weeks of culture.

• 한국세라믹학회지
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• 제46권2호
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• pp.131-136
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• 2009

Radio frequency (RF) plasma treatment is studied for the size reduction and the spheroidization of coarse particles to change them into nano-sized powders of spherical shape in MLCC fields. The uni-nanoadditives manufactured by RF plasma processing for high dispersion have been investigated for the effect on core-shell structure in dielectrics of MLCC. Microstructures have been characterized using scanning electron microscope (SEM), transmission electron microscope (TEM) and Electron Probe Micro Analyzer (EPMA). We compared the distribution of core-shell grains between specimens manufactured using uni-nanoadditive and using mixed additive. In addition, the uniformity of rare earth elements in the core-shell structured grains was analyzed. It was shown, from TEM observations, that the sintered specimen manufactured using uni-nanoadditives had more dense small grains with well-developed core-shell structure than the specimen using mixed additives, which had a homogeneous microstructure without abnormal grain growth and shows broad temperature coefficient of capacitance (TCC) curves in all temperature ranges because of well dispersed additives.

• Applied Microscopy
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• 제27권4호
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• pp.403-416
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• 1997

In order to observe the localization of the specific antigenic protein in the tissue of Paragonimus westermani metacercaria, immunogoldlabeling method was applied using IgG of the dog which were infected with Paragonimus westermani metacercaria and IgG of rabbits which were immunized with purified 23 kDa protein from metacercaria of the Paragenimus westermani. The metacercaria worm tissues obtained from Cambaroides similis were embedded in Lowicryl HM20 medium, treated with infected and immunized IgG and protein A gold complex (particle size; 12 nm) and observed by electron microscope. In the tissue antigen of Paragonimus westermani metacercaria, the content of excretory bladder which was highly dense electron density was constituted in the excretory bladder of the parenchymal tissue. In the metacercaria tissues antigen reacted with IgG of infected dog. Labeled gold particles distributed on the interstitial matrix of parenchymal cells, fibrous granules of parenchymal tissue and the content of excretory bladder. High antigenicity was observed on content of excretory bladder. It was found to be specifically distributed at the tissue of Paragonimus westermani metacercaria. In the tissues antigen reacted with IgG of immunized rabbit. Labeled gold particles randomly distributed on the interstitial matrix and fibrous granules of parenchymal tissue but in the content of excretory bladder of Paragonimus westermani metacercaria, gold particles were richly labeled. Therefore, the 23 kDa protein contained with Paragonimus westermani metacercaria was found protein which was specifically constituted at the content of excretory bladder of Paragonimum westermani metacercaria. The 23 kDa protein was commonly contained from of Paragonimus westermani metacercaria to adult and showed strong antigenicity against the immunized and infected IgG.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.254-258
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• 2005

We have conducted in vitro reconstitution study of ferritin from its subunits FerH and FerL. For the reconstitution, FerH was produced from an expression vector construct in Escherichia coli and was purified from a heat treated cell extract by using one-step column chromatography. FerL was expressed as inclusion bodies. The denatured form of FerL was obtained by a simple washing step of the inclusion bodies with 3 M urea. The reconstitution experiment was conducted with various molar ratios of urea-denatured FerH and FerL to make the ferritin nanoparticle with a controlled composition of FerH and FerL. SDS-PAGE analysis of the reconstituted ferritins revealed that the reconstitution required the presence of more than 40 molar$\%$ of FerH in the reconstitution mixture. The assembly of the subunits into the ferritin nanoparticle was confmned by the presence of spherical particles with diameter of 10 nm by the atomic force microscopic image. Further analysis of the particles by using a transmission electron microscope revealed that the reconstituted particles exhibited different percentages of population with dense iron core. The reconstituted ferritin nanoparticles made with molar ratios of [FerH]/[FerL]=l00/0 and 60/40 showed that 80 to $90\%$ of the particles were apoferritin, devoid of iron core. On the contrary, all the particles formed with [FerH]/[FerL]=85/ 15 were found to contain the iron core. This suggests that although FerH can uptake iron, a minor portion of FerL, not exceeding $40\%$ at most, is required to deposit iron inside the particle.

• Journal of Plant Biology
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• 제39권2호
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• pp.123-126
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• 1996

The pattern of seed storage protein, vicilin, deposition and site of intracellular localization was examined in cotyledon cells of pea (Pisum sativum) seed using the immunocytochemical methods. The vicilin was confined to the cisternae fo the rough endoplasmic reticulum and dictyosome as well as protein granules newly formed in rough endoplasmic reticulum. Vacuolar protein deposites and protein bodies were also labelled by gold particles. After small protein bodies were formed in the rough endoplasmic reticulum, they were transported to large protein bodies and then fused together. Electron dense protein granule, elaborated in the dictyosome, appears to be transported from dictyosome to protein body. A few unlabelled protein granules seem to be accumulated in other type of proteins than vicilin.

• 대한수의학회지
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• 제29권4호
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• pp.541-548
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• 1989

오제스키병 바이러스를 배양세포에다 감염시켜, 냉동 및 araldite포매 초박절편에서 protein A-gold labeling을 통해 바이러스항원 검출을 시도하였다. 오제스키병 바이러스항원은 10nm gold probes로 표지되었으며, 전자밀도가 높은 gold 입자들은 바이러스의 nucleocapsid와 envelope에서 주로 관찰되었고, 초냉동박절표본에서의 immunogold labeling은 조직구조물들과 극히 미미한 비특이결합만을 보였다. 초냉동박절표본에서의 immunogold labeling은 오제스키병 바이러스항원을 검출하는데 있어 효과적이었으며, 이는 또한 여러가지 바이러스들과 속주세포들간의 상호작용에 관한 면역세포화학적 연구에 크게 이용될 수 있을 것으로 생각된다.

• 대한수의학회지
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• 제38권3호
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• pp.488-496
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• 1998

Somatotropes, mammotropes and somatomammotropes of the Korean native goat hypophysis were studied by double immunoelectron microscopy using antisera to growth hormone(GH) and prolactin(PRL), and protein A-gold particles of different sizes. Mammotropes were round or oval in shape, and contained round and electron dense secretory granules. The size of secretory granules was variable from 460nm to 680nm in diameter. Somatotropes were elliptical or triangular in shape and the oval nucei were located eccentrically at the periphery of the cell. Secretory granules of the cell were oval in shape and clearly distinguished from round granules of mammotropes. The size of granules was 320~680nm in diameter, smaller than that of mammotropes. Somatomammotropes contained round or oval secretory granules. The granules had intermediate size between somatotropes and mammotropes. Some of granules contained both GH and PRL, while the others contained only one of them.

• Applied Microscopy
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• 제26권1호
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• pp.33-45
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• 1996

The spermatogenesis of Korean slug, Incilaria fruhstorferi are observed by electron microscope. The results are as follows: The spermatogenesis of Korean slug, Incilaria fruhstorferi, is processed through the five stages; Spermatogonia, primary spermatocyte, secondary spematocyte, spermatid and spermatozoon. The spermiogenesis, the differentiation of the spermatid, is also processed through the five stages. In stage 1, the numerous and round mitochomdria in the cytoplasm are moved around the nucleus of spermatid. In stage 2, the nucleus of spermatid transformed into the oval shape, and the oval nucleus is surrounded by many rough endoplasmic reticulum. In stage 3, the oval nucleus of spermatid is changed to be curved as an arrow, and then two centrioles appeared behind nucleus. The centriole is sucked into the cytoplasm. and almost all the chromatins are changed into heterochromatins. In stage 4, the nucleus of spermatid are transformed into the oval shape, when the lamella plate chromatin of spermatid form in the nucleoplasm. In stage 5, the oval nucleus is then transformed into the stream-line shape when the lamella plate chromatin of spematid gradually concentrated in the nucleus, and long axoneme ($65{\mu}m$ in length) form from the distal centriole. Two long mitochondria in the middle piece and the main piece of spermatozoon array spirally along a long axoneme, and the mitochondria matrix is gradually filled with electron-dense glycogen particles ($0.1{\mu}m$ in size). The axoneme of spermatozoon consists of typical 9+2 microtubular pattern.

• Journal of Microbiology and Biotechnology
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• 제18권11호
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• pp.1762-1767
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• 2008

Image contrast of whole bacteria was compared in Staphylococcus aureus and Escherichia coli depending on pre-stain suspension liquids by energy-filtering transmission electron microscopy. The two bacterial strains were suspended in three most commonly used liquids for negative staining (triple distilled water [DW], phosphate-buffered saline [PBS], and nutrient broth [NB]) and directly observed without staining or stained with neutralized potassium phosphotungstate (PTA), respectively. Even though in low contrast, unstained bacteria were observed owing to their inherent electron density and cell shape in zero-loss (elastic scattering) images. After being suspended in PBS, unstained bacteria appeared to have higher contrast and more refined periphery than DW-suspended ones, and extracellular appendage structures such as fimbriae and flagella could be discerned. The unstained bacteria appeared to be invariably surrounded with electron-lucent precipitates, possibly from PBS. As far as delineation of the structures, the combination of DW or PBS suspension with subsequent staining provided the most satisfactory results, as evidenced by the high contrast of bacterial morphology and appendage structures. However, after being suspended in NB and stained with PTA, bacteria often had too high contrast or poor staining, with electron-dense aggregates around the bacteria. These results suggest that suspension with concentrated organic aliquots including broth media before PTA staining could deteriorate image contrast, and should be used only in dilute form for visualizing bacterial morphology and appendage structures. Moreover the contrast enhancement of unstained bacteria by salt granules would be advantageous in demonstrating bacterial sorption of environmental particles like heavy metals, maintaining minimal contrast for cell imaging.