• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1227-1231
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• 2004

Campylobacter, one of the emerging foodborne pathogens, is highly adaptable to the external environments by changing its morphology. In the present study, a question of whether the whole-cell antibody would still be effective for its detection even though the morphology of C. jejuni was changed was examined. When microaerophilic C. jejuni was exposed to aerobic conditions for 48 h, its morphological change was detected by confocal laser scanning microscope: Its morphology was confirmed as a spiral-bacilli form in microaerobic condition, however, as a coccoid form with a little spiral-bacilli form, when exposed to aerobic conditions. Also, the expressions of the whole-cell proteins of C. jejuni, and the suppression or induction of newly synthesized proteins in both aerobic and microaerobic conditions were analyzed by two dimensional gel electrophoresis. Additionally, immunoblotting assay with the whole cell antibody for the proteins expressed under the two conditions was performed. It was confirmed that the commercial whole-cell antibody of C. jejuni raised in rabbit was reactive. When analyzed with MALDI- TOF MS, the expressed proteins were confirmed as flagellins. Therefore, even though the morphology changed in aerobic condition, these flagellins were expressed and worked as the eitope proteins, thus making it possible to utilize for the development of an immunosensor for real-time detection of any kind of C. jejuni cell.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 춘계학술발표대회
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• pp.41-41
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• 2001

Chromatin configuration and microtubule assembly were determined in porcine maturing and activated oocytes following intracytoplasmic sperm injection. Microtubule localization was confirmed using a mouse monoclonal antibody to $\alpha$-tubulin and detected using a fluorescent labeled goat anti-mouse secondary antibody. DNA was stained with propidium iodide. The image of microtubules and chromatin was captured using laser scanning confocal microscope. In germinal vesicle stage oocyte, sperm chromatin remained condensation and sperm derived microtubules were not observed at 8 to 12 h after sperm injection. At 24 h after injection, the sperm nucleus developed to the metaphase chromatin along the metaphase structure of female nucleus. In some metaphase I stage oocytes, sperm chromatin decondensed at 8 h to 12 h after injection, sperm aster was seen soon after sperm injection. At 24 h after sperm injection into metaphase I stage oocyte, male chromatin developed to the metaphase chromatin while female chromatin extruded first polar body and formed the metaphase chromatin. At 12 to 15 h after sperm injection into preactivated oocytes, condensed sperm nucleus was located in close proximity of female pronucleus. However, the condensed nucleus did not fuse with female pronucleus. In preactivated ocytes, injected sperm remained condensation, a few sperm organized small microtubular aster. Instead, maternal derived microtubules were organized near the female chromatin, which seem to move condensed male chromatin near to the female pronucleus. These results suggest that sperm nuclear decondensing activity and nucleation activity of centrosome during fertilization are cell cycle dependent. In absence of male functional centrosome, female origin centrosome takes over the role of microtubule nucleation for nuclear movement.

• Reproductive and Developmental Biology
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• 제33권1호
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• pp.7-11
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• 2009

This study was performed to confirm the microtubule assemblies and methylation patterns of porcine IVF and parthenogenetic embryos. Cumulus-oocyte complexes were collected and matured in vitro for 42 hr. Oocytes were fertilized by prepared fresh sperm or activated parthenogenetically by exposure to electric stimulation and 6-dimethylaminopurine. Porcine IVF and parthenogenetic embryos were cultured in vitro for 6 days. Embryos were stained by immunofluorescence staining method to observe the dynamic of nucleus and microtubules in the first mitotic phase and the methylation patterns in different developmental stages. After then, samples were confirmed and analyzed through a laser-scanning confocal microscope. IVF embryos had a centrosome originated from sperms, which was shown a $\gamma$-tubulin spot. However, $\gamma$-tubulin spot was not observed in parthenogenetic embryos. A lower methylation level was observed in IVF embryos compared to parthenogenetic ones at the morula and blastocyst stages. In conclusion, it is considered that microtubule assemblies and genetic regulation mechanism differ between parthenogenetic and IVF embryos.

• 한국안광학회지
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• 제19권3호
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• pp.413-418
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• 2014

목적: 한국관박쥐 망막의 기능을 알아보기 위해서 흥분성 신경전달물질인 글루타메이트 수용체의 분포도를 분석하였다. 방법: 성체 한국관 박쥐의 망막을 $40{\mu}m$ 수직 절편 한 후 표준면역세포화학법을 이용하였다. 면역형광이미지는 Bio-Rad MRC 1024 공초점 현미경을 사용하여 얻었다. 결과: AMPA (GluR1-4), Kainate (GluR5-7, KA1-2), NMDA (1, 2A, 2B)는 내망상층과 외망상층에 주로 분포되어 있었다. KA1은 신경절세포층에도 많은 수의 수용체가 존재하였다. 결론: 한국관박쥐는 포유류망막에 있는 신경세포와 신경전달물질을 동일하게 가지고 있었다. 한국관박쥐도 기능적 망막을 가지고 있음을 제시한다.

• 대한소아치과학회지
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• 제45권2호
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• pp.195-202
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• 2018

본 연구의 목적은 어린이들이 섭취하는 비타민 제제들의 우식원성을 치아우식 유발지수와 Streptococcus mutans의 활성정도 및 산생성능을 통해 분석하는 것이다. 4가지 비타민, 노마(NM), 세노비스 키즈(CK), 애니멀 퍼레이드(AP), 캐릭터 비타민(CV)를 대상으로 진행하였다. 치아우식 유발지수를 산출한 결과 AP, CV, CK, NM 순으로 작아졌다. pH 측정 시 모든 실험군들의 초기 값은 산성을 나타내었다. S. mutans의 군집 형성 단위를 분석한 결과 NM, CV은 대조군에 비해 더 높은 증식률을 보였고(p < 0.05), CK와 AP (p < 0.05)는 대조군에 비해 더 낮은 증식률을 보였다. 공초점 현미경으로 관찰하였을 때 실험군들은 대조군에 비해 높은 세균 활성도를 보였다. 비타민 제제들의 세균 활성도와 산도를 고려해 볼 때, 어린이의 구강 건강을 위해서는 세심하게 고려하여 섭취해야 할 것이다.

• 펄프종이기술
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• 제31권1호
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• pp.39-45
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• 1999

Refining in papermaking plays an important role in changing fiber properties as well as paper properties. The major effects of refining on pulp fibers are internal and external fibrillation, fiber shortening, and fines formation. Many workers showed that internal fibrillation of the primary refining effects was most influential in improving paper properties. In particular, refining produces separation of fiber walls into several lamellae, thus causing fiber wall swelling with water penetration. This leads to the increase of fiber flexibility and of fiber-to-fiber contact during drying. If the fibers are very flexible, they will be drawn into close contact with each other by the force of surface tension as the water is removed during the drainage process and drying stages. In order to study the effect of fiber wall delamination on paper properties, cross-sectional image of fibers in a natural condition had to be generated without distortion. Finally, it was well recognized that confocal laser scanning microscope (CLSM) could be one of the most efficient tool for creating and quantifying fiber wall delamination in combination with image analysis technique. In this study, the CLSM could be used not only to observe morphological features of transverse views of swollen fibers refined under low and high intensity, but also to investigate the sequence of fiber wall delamination and fiber wall breakage. From the CLSM images, increasing the specific energy or refining decreased the degree of fiber collapse, fiber cross-sectional area, fiber wall thickness and lumen area. High intensity refining produced more external fibrillation.

• 한국축산식품학회지
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• 제34권2호
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• pp.257-261
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• 2014

The objective of this study was to evaluate the effects of NaCl on the biofilm formations of the isolate from Staphylococcus aureus outbreaks linked to ham. The S. aureus ATCC13565 isolated from ham was exposed to NaCl concentrations of 0%, 2%, 4%, and 6% supplemented in tryptic soy broth (TSB) for 24 h at $35^{\circ}C$, followed by plating 0.1 mL of the culture on tryptic soy agar containing 0%, 2%, 4%, and 6% NaCl, respectively. After incubating at $35^{\circ}C$ for 24 h, the colonies on the plates were collected and diluted to $OD_{600}$ = 0.1. The diluents of S. aureus were incubated on a 96-well flat bottom plate containing TSB plus the appropriate NaCl concentrations, and the biofilm formation was quantified by crystal violet staining after being incubated at $35^{\circ}C$ for 9 h. Confocal laser scanning microscope (CLSM) was also used for visualizing the biofilm formation of S. aureus at NaCl concentrations of 0%, 2%, 4%, and 6%. The transcriptional analysis of biofilm-related genes, such as icaA, atl, clfA, fnbA, sarA, and rbf, was conducted by quantitative real-time PCR. Crystal violet staining and CLSM showed that the biofilm formations of S. aureus increased (p<0.05) along with the NaCl concentrations. Moreover, the expression of the icaA genes was higher at the NaCl concentrations of 4% and 6% as compared with 0% of NaCl by approximately 9-folds and 20-folds, respectively. These results indicated that the NaCl formulated in processed food may increase the biofilm formations of S. aureus by increasing the icaA gene expressions.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.171-175
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• 2006

The aim of this in vitro study was to test the effect of microinjection (Mi) of foreign gene into the rabbit egg pronucleus and epidermal growth factor (EGF) addition on the blastocyst rate, the cell number and the diameter of embryos, and to determine possible relationships between embryo cell number and embryo diameter. Blastocyst rate was significantly decreased in gene- Mi (G-Mi/E0) group (63.1%) comparing to intact ones (83.5%, $p_1$<0.05). The addition of EGF at 20ng/ml (G-Mi/E20) or 200 ng/ml (GMi/ E200) to gene-Mi embryos did not affect blastocyst rate (65.6 and 55.2% resp.). As a control for Mi, the eggs were microinjected with the same volume of phosphate-buffered solution (PBS-Mi) instead of the gene construct solution. Cell numbers and embryo diameters were measured from embryo images obtained on confocal laser scanning microscope. Bonferroni-modified LSD test showed that the embryo cell number in PBS-Mi group was significantly lower ($p_1$<0.05) and in gene-Mi group was tended to decrease compared with intact embryos. Embryo diameter was not different among experimental groups. No effect of EGF given at any doses both on the cell number and embryo diameter was found. A positive correlation between cell number and embryo diameter was observed in all groups of embryos. Since embryo diameter was not changed under the influence of Mi or EGF addition in this study, this seems to be more conservative characteristics of the embryo morphology. These results suggest that the pronuclear microinjection compromises developmental potential of embryos, decreasing blastocyst rate and embryo cell number, whilst embryo diameter is not affected. No effects of EGF on studied parameters were confirmed. Declined quality of Mi-derived embryos is caused by the microinjection procedure itself, rather than by the gene construct used.

• 지질공학
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• 제23권3호
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• pp.271-281
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• 2013

본 연구에서는 임기광산과 일광광산의 시료를 활용하여 동결/융해 실험을 진행하고 시료의 물성변화 및 표면 거칠기의 변화를 관찰하여 풍화양상을 분석하였다. 본 연구에서 사용된 동결/융해 실험의 온도 범위는 우리나라의 여름과 겨울철의 온도를 고려하여 $-20^{\circ}C$ ~ $+40^{\circ}C$로 설정하고 각각 설정한 온도까지 도달하는데 각 1시간, 목표온도를 유지하는데 1시간으로 총 4시간을 1 주기(cycle)로 하여 매 20 주기마다 풍화양상을 관찰하였다. 그 결과 동결/융해 시험의 반복횟수가 증가하면서 시료의 측정된 물성 값 중 공극률(porosity)은 두 개의 지역에서 0.05%와 0.15%의 차이를 보이며 증가하였고, 입자의 부피와 건조질량, 포화질량은 비교적 미세하게 감소하는 경향을 보였다. 또한, 다초점 레이저 스캔 현미경을 통해서는 측정한 선 거칠기와 면 거칠기 인자의 값들은 시간이 경과함에 있어 일정하게 증가 및 감소하는 경향을 보였으며, 다초점 레이저 스캔 현미경을 통해 촬영한 사진에서도 표면 거칠기가 변하는 것을 확인할 수 있었다.

• 한국주조공학회지
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• 제23권5호
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• pp.276-285
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• 2003

In the undercooled melt of $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy, the solidification behavior including nucleation and growth of crystals at the micrometer level has been observed in-situ by use of a confocal scanning laser microscope combined with an infrared image furnace. The $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy specimens were cooled from the liquid state to glass transition temperature. 575 K, at various cooling late under a helium gas flow. According to the cooling rate, the morphologies of the solidification front are changed among various types, irregular jog like front, columnar dendritic front, cellular grain, star like shape jog and fine grain, etc. The velocities of the solid-liquid interface are measured to be $10^{-5}{\sim}10^{-8}$ m/s which are at least two orders higher than the theoretical crystal growth rates. Combining the morphologies observed in terms of cooling rates and their solidification behaviors, we conclude that phase separation takes place in the undercooled molten $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy. The continuous cooling transformation (CCT) diagram was constructed from solidification onset time at various linear cooling conditions with different rate. The CCT diagram suggests that the critical cooling rate for glassy solidification is about 1.5 K/s, which is in agreement with the previous calorimetric findings.