• Applied Microscopy
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• 제28권3호
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• pp.315-328
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• 1998

The present study was carried out to investigate the effect of ultrasonic bath in tissue preparation for transmission electron microscopy. The method used standard reagents and media, and employed ultrasonic bath agitation to accelerate fluid exchange. The liver kidney, stomach and cardiac muscle tissues of male Sprague-Dawley rats were used for the experiment, and the experimental design was divided into 4 groups; The control group using rotators (Traditional method, 1,625 mins) and the three experimental groups using ultrasonic bath (UB) in the primary fixation through the infiltration processes (UB I; 62.5 mins, UB II; 125 mins, UB III; 250 mins). The results were as follows; 1. In the control group, tissues were easily sectioned, and showed well preserved intact membranes, and cell organelles such as mitochondria, lysosome, peroxisome, rough endoplasmic reticulum and smooth endoplasmic reticulum. 2. In the UB treated group I, tissues showed holes due to the inadequate removal of both water and fluids used in the dehydration process. Also the mitochondria of cell organelles, especially, showed swollen intracristal spaces and dense matrices due to poor fixation. 3. In the UB treated group II, tissues showed good preservation of cell organelles and specimen slice sections. Also, no holes were observed. 4. In the UB treated group III, tissues showed leaching of structural components in the cytoplasm, but no holes were observed. In conclusion, the ultrasonic bath procedure takes approximately 120 minutes from specimen fixation to resin infiltration and gives excellent results.

• Applied Microscopy
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• 제39권2호
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• pp.185-189
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• 2009

초파리 망막 세포의 미세구조연구는 1960년대부터 수행되어 왔으나, 이 연구들은 2차원 구조연구에 국한되어 있었다. 본 논문은 초고압 동결법, 연속절편법, 초고압 전자현미경, 그리고 3차원 구조 구현법을 이용하여 초파리 성체의 망막 세포에 존재하는 미토콘드리아, 미세소관, 그리고 핵의 3차원 분포를 연구한 결과이다. 이를 통하여 미토콘드리아는 주로 세포막 가까이에 위치하며, 그 수는 렌즈와 가까운 말단부분에 많은 것을 알 수 있었고, 미세소관은 렌즈와 가까운 망막 말단부분과 시신경과 연결되는 기부에 특히 많은 수가 존재하는 것을 알 수 있었다. 이들은 망막 변성의 원인이 되는 세포 소기관이므로, 이들의 세포 내 3차원 분포는 병의 원인을 연구하는 데 있어 중요한 자료가 될 것으로 사료된다.

• Applied Microscopy
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• 제38권3호
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• pp.251-257
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• 2008

본 연구는 탈색회수에 따른 모발의 인장강도 변화를 측정하여 건강모발과 비교하였으며, 인장시험 결과 절단된 모발의 단면을 주사전자현미경을 사용하여 형태학적 변화 양상을 관찰하였다. 인장시험에서 건강모발은 인장강도가 $14.66g/cm^2$으로 측정되었고, 탈색 1회, 2회, 3회 모발은 각각 $12.95g/cm^2$, $12.61g/cm^2$, $11.43g/cm^2$으로 나타났다. 결국 탈색모발은 탈색 횟수가 증가할수록 인장강도가 감소하였다. 건강모발과 탈색모발의 인장강도 시험 후 절단된 모발 단면의 주사전자현미경 관찰에서 건강모발은 표면의 큐티클세포들이 들떠서 분리되어 있었으며, 탈색모발의 표면은 건강모발의 표면보다 더 심하게 큐티클세포들이 분리에 있었다. 탈색모발의 큐티클세포들은 모발표면의 바깥쪽으로 심하게 휘어져 분리되어 있었다. 큐티클세포의 분리는 세포막사이 복합체의 파괴에 의해서 일어났으며 큐티클세포의 세포질의 일부인 내큐티클의 파괴에 의한 분리는 일어나지 않았다.

• Applied Microscopy
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• 제45권4호
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• pp.249-253
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• 2015

Microorganisms specifically groups of bacteria exhibiting physiological activities of production of acids are a major cause of concern because of their ability to induce corrosion in oil field pipelines and metal systems involved in water handling. Water Injection Stations as a means of secondary recovery from existing oil producing reservoirs, are often employed in most upstream oil and gas industries to ensure replenishment of voidage, maintenance of reservoir pressure and optimization of crude emulsion throughput. In the present study, scanning electron microscopy of macroscopic orange coloured slime formations sampled from leaking valves on the flow-lines of a Water Injection Stations of Oil India Limited revealed the presence of filamentous bacterial mats in association with diatoms. The species composition of the acidic slime formations from the sampled locations reveal the possible role of acid producing iron oxidizing bacteria (IOB) like Acidithiobacillus ferrooxidans in association with Gomphonema sp. in creating conditions for bio-corrosion.

• Applied Microscopy
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• 제18권2호
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• pp.167-176
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• 1988

Extrachromosomal circular DNA complexes from erythrocytes and splenocytes isolated from Carassius carassius were examined by mica-press-absorption method. The method was described that released small polydisperse circular DNA molecules in situ from the erythrocytes and the splenocytes and that allows selective observation of the small circular DNA complexes bound to cellular components. The released polydisperse circular DNA complexes were absorbed preferentially on mica in a divalent cation-free medium then processed for electron microscopy. Small circular DNAs showed a heterogeneous size distribution of $2{\sim}10{\mu}m$ with a mean contour length of $4.3{\mu}m$ for the circulating erythrocytes and that of $0.7{\sim}3.6{\mu}m$ with a mean contour of length $2.04{\mu}m$ for the splencytes. Cells contained $100{\sim}300$ copies and $300{\sim}700$ copies obtained from the erythrocytes and the splenocytes, repectively. Possible biological functional implications for size distribution of extrachromosomal circular DNAs are discussed.

• Applied Microscopy
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• 제25권2호
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• pp.1-10
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• 1995

This study was carried out to clarify the neuronal organization in pineal body of catfish. The pineal body was observed by acetylcholinesterase histochemistry and electron microscopy. The neuronal types observed in the pineal body of catfish were bipolar and multipolar cells. Multipolar cells were found throughout the pineal end vesicle and whole stalk, but bipolar cells only in the end vesicle and distal stalk. The pineal tract was formed by the long axons of these neurons. The neuronal clusters(pineal ganglia) were also observed in the end vesicle. In summary, the type of neurons in catfish pineal was different from that of other species, and the neuronal distribution differed depending on the region of pineal body. These results reflect the interspecific and regional differences of the pineal organization of fishes.

• Applied Microscopy
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• 제28권3호
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• pp.263-271
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• 1998

Oocyte maturation of the swordtail (Kiphophorus hellerii) was investigated by light and electron microscopy. In the ovary of the swordtail, various staged oocytes were observed, Mature oocytes were located in ovarian cortex, meanwhile immature ones were positioned in ovarian medulla. The oocyte was surrounded by several structures or cells such as chorion, follicle cells, follicular theaca and ovarian epithelium, respectively, from the inside toward outside. Growing and maturing oocytes healed numerous microvilli which interconnected the oocyte and the follicle cells to communicate each other. The mature oocyte had the electron dense chorion which appeared to be ultrastructure of two layers and contained pore canals. Oocyte maturation was characterized by not only the enlarged cell size and well differentiated cell organelles, brit also the increases of fat droplets, pinocytotic vesicles and yolk granules.

• Applied Microscopy
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• 제43권1호
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• pp.9-13
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• 2013

The helium ion microscope (HIM) has recently emerged as a novel tool for imaging and analysis. Based on a bright ion source and small probe, the HIM offers advantages over the conventional field emission scanning electron microscope. The key features of the HIM include (1) high resolution (ca. 0.25 nm), (2) great surface sensitivity, (3) great contrast, (4) large depth-of-field, (5) efficient charge control, (6) reduced specimen damage, and (7) nanomachining capability. Due to the charge neutralization by flood electron beam, there is no need for conductive metal coating for the observation of insulating biological specimens by HIM. There is growing evidence that the HIM has substantial potential for high-resolution imaging of uncoated insulating biological specimens at the nanoscale.

• The Plant Pathology Journal
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• 제17권6호
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• pp.329-335
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• 2001

Yellowing disease of palms caused by phytoplasma is spreading in the Arabian Gulf region. Surveys were conducted to determine the occurrence of the disease. Electron and fluorescence microscopy, and polymerase chain reaction (PCR) techniques were used to detect the phytoplasma associated with the yellowing disease of ornamental palm Washingtonia sp. grown in Kuwait. An accumulation of phytoplasmal DNA was observed by fluorescence microscopy in phloem tissues of diseased palms. Electron microscopy showed that phytoplasma cells were primarily confined to the phloemsieve elements of tissue samples collected from infected mature palms in the field. The pathogen was identified on the basis of molecular analysis using universal and specific nested primers in PCR amplifications. Prokaryotic 16S rDNA gene was detected in amplified PCR products. Nested PCR resulted in DNA amplification of 1.2 kbp fragment. This is the first report of a phytoplasmal rDNA gene identified from the putative causal pathogen of yellows in ornamental palms in the Arabian Gulf region.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.286-286
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• 2006

We report on a fascinating morphology; giant spherical conducting polythiophene by the in-situ gamma radiation-induced chemical polymerization method. The resultant micron-size buckyball-shaped polymer structures were identified by high resolution transmission electron microscopy and scanning electron microscopy. Different characterizations e.g. Fourier transform infrared, x-ray diffraction, and x-ray photoelectron microscopy were utilized to prove that the new morphological conducting polythiophene was synthesized successfully by this novel method.