김치에서 분리한 Lactobacillus sp. JC-7과 Lactobacillus acidophilus 88간의 Electrofusion 최적조건 설정

조영배,최현정,백형석,전홍기 부산대학교 유전공학연구소 1997 분자생물학 연구보 Vol.13 No.-

김치 발효 숙성기간을 연장하고 신선도를 오랫동안 유지 할 수 있는 김치발효 starter의 개발을 목적으로 최적숙성기에 있는 김치로부터 bacteriocin생성능이 없는 유산균을 분리하여 동정하였으며, bacteriocin생성능이 우수한 L.acidophilus 88을 융합시키기 위해 electrofusion에 대한 최적 조건을 검토하였다. 분리균주는 Lactobacillus속으로 동정되어 Lactobacillus sp. JC-7이라 명명하였다. Electrofusion에 의해 생성된 융합주를 식별하기 위해 streptomycin(2.5㎎/ml)에 내성을 나타내는 Lactobacillus sp. JC-7변이주와 kanamycin(600㎍/ml)에 내성을 나타내는 L.acidophilus 88변이주를 분리하였다. Electrofusion을 100V/㎝, 120msec(72ohms,1670 capacitance) 에서 수행했을 때 융합효율이 가장 양호하였으며 전기장의 세기와 시간이 중가할수록 융합 효율이 현저히 감소하였다. 2가 양이온은 농도가 중가할수록 대체적으로 융합효율을 감소시키는 경향을 나타내었으나 1mM MGCl_2에서는 대조군에 비해 융합효율이 약간 증가하였다. PEG매개에 의한 융합법의 융합효율을 비교한 결과, 융합효율은 chemical fusion<electrofusion<electrofusion+20% PEG순을 나타내었다. Evaluation of Optimum Conditions for the Electrofusion between Lactobacillus sp. JC-7 Isolated from Kimchi and Lactobacillus acidophilus 88. Young-Bae Jo, Hyun-Jung Choi, Hyung-Suk Baik and Hong-Ki Jun*. Department of Microbiology, Pusan National University, Pusan 609-735,Korea-A lactic acid bacterium was isolated from kimchi. The isolated strain was identified as the genus Lactobacillus thrugh its morphological characteristics and named as Lactobacillus sp. JC-7. The optimum conditions for the electrofusion between streptomycin(2.5㎎/ml)resistant mutant of Lactobacillus acidophilus 88 and kanamycin(600㎍/ml) resistant mutant Lactobacillus sp. JC-7 were evaluated. The highest number of fusants were obtained at a capacitance value of 120msec(1670㎌), a field strength of 100V/㎝,and a pulse controller setting of 72Ω. The potimum pH of elecroporation buffer was 7.5 and the concentration of divalent cation was 1mM MG^2+. Electrofusants were efficiently obtained by addition 20% polyethylene glycol to electroporation buffer. The yield of fusion was better than that of using polyethylene glycol mediated chemical induction.

NANOARCHITECTURES: High‐Resolution Patterning of Various Large‐Area, Highly Ordered Structural Motifs by Directional Photofluidization Lithography: Sub‐30‐nm Line, Ellipsoid, Rectangle, and Circle Arrays (Adv. Funct. Mater. 10

Lee, Seungwoo,Kang, Hong Suk,Park, Jung‐,Ki WILEY‐VCH Verlag 2011 Advanced functional materials Vol.21 No.10

<P>A principal challenge in nanopatterning is to beat the resolution limit of established methods. On page 1770, Seungwoo Lee, Hong Suk Kang, and Jung‐Ki Park present the directional photofluidization of azopolymers, which allows the generation of large‐area, highly ordered nanoarchitectures with precisely controlled structural features. Additionally, this approach can offer unprecedented flexibility in control of the final feature size, and, simultaneously, its fluidic behavior under light irradiation signifi cantly reduces the line‐edge roughness </P>

PSPICE Macromodeling에 의한 PLL의 주파수 특성연구

鄭天錫,朴明烈,金世烈,金洪九 울산대학교 1996 공학연구논문집 Vol.27 No.2

본 논문은 범용화되어있는 Microsim 사의 PSPICE를 이용해서 위상동기루프(PLL) Micromodeling으로 설계하여 시뮬레이션 하였다. PLL 회로는 위상검출기와 전압제어 발진기 그리고 루프 필터로 이루어져 있다. RC 저역통과 필터와 Butterworth 필터 그리고 Chebyshev 필터 등을 이용하여 입력주파수 변화에 따른 루프필터의 주파수 특성을 분석하였다. 그리고 전압제어 발진기의 자주발진주파수를 2.5kHz, 19kHz로 고정할 때의 주파수 스펙트럼을 분석하였다. 자주발진주파수 2.5kHz에서 Chebyshev 필터의 경우 upper lock range와 lower lock range는 똑같이 1,056Hz, 1,056Hz였고 upper capture range와 lower capture range는 536Hz, 540Hz였다. 또한 시뮬레이션 과정에서 삼각파를 구형파로 바꾸는 VCO의 슈미트 트리거단에서 수렴문제로 인하여 19KHz 이상에서는 상당히 긴 시뮬레이션 시간을 필요로 하는 단점이 있었다. 그렇지만 낮은 주파수대에서 주파수 특성 분석의 용이함과 정확성 및 복잡한 회로의 간략화에서 매크로모델링의 타당성을 보였다. With today's general simulator, PSPICE, a phase-locked loop(PLL), which consists of a phase detector(PD), a voltage-controlled oscillator(VCO), and a low-pass filter(LPF), is designed and simulated in macromodeling technique. By using a RC LPF, a Butterworth, and a Chebyshev LPF in turn, the frequency characteristics of the outputs according to the variations of the inputs are analyzed respectively. When 2.5KHz and 19KHz are selected as two specified free running frequencies in VCO block, the frequency spectrums of the outputs show that in case of the Chebyshev LPF at 2.5KHz, the upper and lower rock ranges have the same frequency ranges, 1056Hz, and the upper and lower capture ranges are 536Hz and 540Hz respectively. Furthermore, the simulation takes a long time especially above 19KHz, because of the convergence problem at schmitt trigger section, where the triangular wave is changed into the rectangular wave. However, this paper shows some validity that this macromodeling technique is one of the easy and accurate methods in analyzing the frequency characteristics, and useful in simplifying the complicated circuits at low frequency band below 19KHz.

사람 위선암에서 cathepsin L의 발현증가

홍원선,홍석일,박인철,손영숙,정훈용,양석균,김해련,민영일 울산대학교 의과대학 1996 울산의대학술지 Vol.5 No.1

cathepsin L은 lysosomal cysteine 단백분해효소로서 기저막(basement membrane)과 세포외기질(extracellular matrix)을 파괴하여 암세포의 침윤과 전이에 중요한 역할을 하는 물질로 알려져 있다. 이러한 cathepsin L에 대한 mRNA 발현도를 5개의 사람 위선암(gastric adenocarcinoma) 세포주와 5명의 위선암 환자에서 채취한 조직에서 방사능으로 표지된 cathepsin L특이 cDNA를 사용한 Northern blot법으로 측정하였다. 위암의 전이병소에서 수립한 세포주인 SNU-5, SNU-16, MKN-45와 Kato Ⅲ에서는 cathepsin L mRNA가 발현되었으나 원발병소에서 수립한 AGS 세포주에서는 mRNA의 발현이 관찰되지 않았다. 5명의 위암 환자에서는 원발병소, 전이가 확인된 임파절 및 암 근처 정상 위점막에서 각각 조직을 채취하여 cathepsin L mRNA의 발현을 측정하였다. 원발병소와 전이병소에서는 모두 cathepsin L mRNA가 발현되었으나 정상 위점막조직에서는 전예에서 mRNA 발현이 관찰되지 않았다. 한편 mRNA의 발현도는 1예에서는 전이병소가 원발병소에 비해 높았으나, 2예에서는 전이병소에서 발현도가 낮았으며, 나머지 2예에서는 원발병소와 전이병소 사이에 차이가 없어, 원발병소와 전이병소 사이에 mRNA의 발현도의 일관성 있는 경향은 관찰되지 않았다. 이상의 결과는 cathepsin L은 위암의 발생과 진행에 있어 암세포의 침윤과 전이를 촉진하는 것 이외에 또 다른 역할을 할 가능성을 시사하고 있다고 사료된다. Cathepsin L, a lysosomal cysteine protease, is known to play an important role in cancer invasion and metastasis by degrading the components of basement membrane and extracellular matrix. The mRNA expression of cathepsin L was determined by Northern blot analysis using a radiolabeled cDNA specific for cathepsin L in five human gastric adenocarcinoma cell lines and five surgical specimens of primary gastric adenocarcinomas, their metastatic lymph nodes and matched adjacent normal mucosae. The mRNA of cathepsin L was expressed in all of the four cell lines established from the metastatic sites, SNU-5, SNU-16, MKN-45 and Kato Ⅲ, while not detected in one cell line established from the primary site, AGS. The mRNA was expressed in all of the five primary and five metastatic cancer specimens tested, while it was not detected in all matched normal mucosae. The intensities of the mRNA expressions, however, did not show the consistent pattern between primary sites and metastatic lymph nodes. These results suggest that cathepsin L may have the other function in addition to facilitation of the invasion and metastasis during the development and progression of stomach cancer.

익상구개와에 발생한 악성 섬유조직구종 1예

홍정표,김인섭,김문석,윤주헌 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.9

구형 Helicobacter pylori의 중성구 매개 산화활성

홍원선,김혜원,이학성,명승재,정훈용,양석균,김진호,민영일,정명희 대한암예방학회 2000 Journal of cancer prevention Vol.5 No.3

Caco-2 세포 단층막 투과 실험시 교반이 약물의 투과계수에 미치는 영향

홍순선,유호정,이홍,정석재,김대덕,심창구 한국약제학회 2005 Journal of Pharmaceutical Investigation Vol.35 No.2

The unstirred water layer (UWL), which has been known to exist in the boundary of the intestinal lumen and intestinal wall, often behaves as an absorption barrier especially for lipophilic drugs. The intestinal absorption of drugs is often characterized using Caco-2 cell monolayers grown on Transwell polycarbonate membranes. The permeability (Pare) of drugs across the cell monolayer might be influenced by the agitation of the donor compartment, since the width of UWL on the surface of the cell monolayer would be reduced by the agitation. In this study, the effect of agitation of the donor compartment with 60 rpm on the permeability was measured for 12 drugs with a wide range of lipophilicity and permeability. The of mannitol, tributylmethyl ammonium, cimetidine, ranitidine, hydrocortisone, benzylpenicillin and loxoprofen was not influenced by the agitation, while the P_(app) of theophylline, propranolol, YH439, phenylpropanolarnine and testosterone was increased by the agitation. There was a significant correlation between the increase of P_(app) by agitation and the lipophilicity for the compounds having P_(app) > 2 x 10^(-5) cm/sec. No correlation was observed for the difference in P_(app) by agitation and the molecular weight, or lipophilicity of the drugs. Therefore, the agitation rate of the donor compartment in the Caco-2 cell monolayer study should be carefully controlled in order to estimate Pap, reproducibly especially for iipophilic drugs.

國內判例考察을 통한 建設클레임의 效率的 管理方案 硏究 : Based on Judicial Precedents

홍정석 남서울대학교 1999 남서울대학교 논문집 Vol.5 No.-

Nowadays claims are considered as a part of contract administration in the construction industry. One of the most common claims in construction is a delay issue. Construction claims have been occurred due to an unanticipated circumstance. Analysis of judicial precedents is important because those are the last meanings, which have authoritative power. But there are so many troubles to analyze them because there is no standard method to prove causes, effects, and contract damages in our construction industry. Guidelines for application of construction claims the settlement method have been presented.

영상색 재현기술에 관한 연구

김홍석,백정기 대진대학교 1998 大眞論叢 Vol.6 No.-

To achieve the color reproduction on the CRT monitor, an algorithm considering the background effect and the compensation of white difference between two media is developed. This algorithm is tested to SONY 200sf color monitor for reproducing the Macbeth colorchecker 24 colors. The comparison of the chromaticity coordinates between reproduced colors and color chips shows good agreement.

R-12 냉매용 냉동장치의 성능에 미치는 R-12와 R-134a 냉매의 효과

이홍기,장동호,정용진,강형석 강원대학교 산업기술연구소 2000 産業技術硏究 Vol.20 No.B

High pressure, pressure ratio, refrigerating effect, heat transfer from the condenser and the power of the compressor etc. of a self-made refrigeration equipment for R-12 are investigated when R-12 and R-134a are used as the coolants. The comparison between the performance for R-12 and that for R-134a is made. As a result, R-134a is better than R-12 in the view of high pressure, refrigerating effect and the coefficient of performance and vice versa in the view of pressure ratio, exit gas temperature from the compressor and heat transfer from the condenser.