• BMB Reports
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• 제38권3호
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• pp.259-265
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• 2005

Proteins must fold into their correct three-dimensional conformation in order to attain their biological function. Conversely, protein aggregation and misfolding are primary contributors to many devastating human diseases, such as prion-mediated infections, Alzheimer's disease, type II diabetes and cystic fibrosis. While the native conformation of a polypeptide is encoded within its primary amino acid sequence and is sufficient for protein folding in vitro, the situation in vivo is more complex. Inside the cell, proteins are synthesized or folded continuously; a process that is greatly assisted by molecular chaperones. Molecular chaperones re a group of structurally diverse and mechanistically distinct proteins that either promote folding or prevent the aggregation of other proteins. With our increasing understanding of the proteome, it is becoming clear that the number of proteins that can be classified as molecular chaperones is increasing steadily. Many of these proteins have novel but essential cellular functions that differ from that of more 'conventional' chaperones, such as Hsp70 and the GroE system. This review focuses on the emerging role of molecular chaperones in protein quality control, i.e. the mechanism that rids the cell of misfolded or incompletely synthesized polypeptides that otherwise would interfere with normal cellular function.

• Journal of Magnetics
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• 제10권3호
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• pp.128-132
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• 2005

We report optical ab-plane properties of the layered sodium cobaltate, $Na_xCoO_2$ for x = 0.35 and 0.75. Two samples show metallic behaviors according to dc resistivity transport. Overall temperature dependent optical conductivities of both samples are very similar to those of the high temperature superconducting underdoped cuprates. We found that the optical scattering rate of x = 0.75 sample, which is in a Curie-Weiss metallic phase, varies linearly (non-Fermi liquid) with frequency and temperature while that of x = 0.35 sample, which is in a paramagnetic metallic phase, varies quadratically (Fermi liquid) with frequency and temperature. Both x = 0.35 and 0.75 samples have an onset of scattering around $600\;cm^{-1}$ which can be attributed to the interaction of charge carriers with a bosonic collective mode in a system.

• Restorative Dentistry and Endodontics
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• 제17권2호
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• pp.365-382
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• 1992

The purpose of this study was to evaluate the adaptation of filling material to the dentinal walls of root canals with and without smear layer. Fifty extracted upper and lower anterior teeth were selected, and the root canals were instrumented with K - files 1mm short of the apical foramen by step - back method. The teeth were randomly divided into two groups of 25 each : in the group I, smear layers were not removed, and in the group II, smear layers were removed by 15% EDTA solution. Again the two groups 25 teeth were randomly divided into unfilled contol group and filling groups(lateral, ultrasonic, ULTRAFIL, McSpadden compaction group). Upon completion of root canal filling, the teeth were grooved on the both the labial and lingual surfaces and then split with mallet and chisel. Each specimens were examined with JSM - 840 Scanning Electron Microscope (JEOL., Japan). The results were as follows : 1. In the contol group, dentinal tubules of group I couldn't be distinguished in the canal wall, but those of group II appeared to be open and patent. 2. In the filling groups of group I, the tubular penetration of the sealer or gutta percha couldn't be seen, but in the filling groups of group II, it could be seen except McSpadden compaction group. 3. In the filling groups, ULTRAFIL group showed the best adaptation of filling material to root canal wall among the group I, and lateral and ultrasonic condensation group showed the best adaptation of filling material among the group II. McSpadden compaction group showed the worst adaptation in group I, II. 4. Generally, the group II showed better adapation of filling material to root canal wall than the group I.

• 한국응용곤충학회지
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• 제56권3호
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• pp.267-273
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• 2017

귤나무속 과수의 주요 해충인 귤응애의 방제효과 극대화를 위해 괭이밥의 천적유지식물 적용 가능성을 검토하였다. 괭이밥을 지피식물로 조성한 처리구에서 일반 초생재배구에 비해 포식성 응애류 밀도가 평균 3배 이상 높게 나타났으며, 제초구에 비해 3.7배 낮은 귤응애 발생 밀도를 확인 할 수 있었다. 칠레이리응애는 괭이밥응애 알과 성충을 포식하지 못하였고, 사막이리응애는 일일 평균 괭이밥응애 알 1.96개와 암컷 성충 1.93개를 포식하였다. 온도 $23{\pm}1^{\circ}C$, 습도 $70{\pm}5%$, 광조건 16L : 8D로 설정된 사육실에서 괭이밥응애 알에서 성충까지 17.4일이 소요되었으며 77.5%의 부화율과 84.8%의 유충생존율을 확인하였다.

• 성인간호학회지
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• 제19권3호
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• pp.508-516
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• 2007

Purpose: This study was to examine the effects of electric stimulation therapy on chronic knee pain, exercise self-efficacy, and quality of life in Korean elderly women. Methods: The design was an unequivalent control pretest-posttest study. Samples were total of 60 (experimental: 30, control: 30) elderly women with healthy cognitive and communication abilities aged 65 years old and above. The experimental treatment involved was the electric stimulation of both thigh quadriceps muscles for 15 minutes per treatment, 3times per a week, for a total of 12 weeks. Measurements taken were S-F MPQ and AIMS for chronic knee pain, exercise self-efficacy measurement for exercise self-efficacy, and S-F 36 scale for quality of life. Data were analyzed using SPSS PC+ 12. Results: Chronic knee pain according to the Short-Form McGill Pain Questionnaire (t=43.563, p=.000) and Arthritis Impact Measurement Scale (t=31.364, p=.000) were significantly decreased in the experimental group by the application of electrical stimulation therapy. Exercise self-efficacy (t=107.116, p=.000) and quality of life (t=76.429, p=.000) were significantly increased in the experimental group by the application of electrical stimulation therapy. Conclusion: Electrical stimulation therapy could be a more effective primary nursing intervention in decreasing chronic knee pain, and on increasing exercise self-efficacy and quality of life for Korean elderly women.

• 한국축산식품학회지
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• 제25권2호
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• pp.203-209
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• 2005

유전자수준의 염기서열에 근거를 둔 유전자 감식기법을 활용하여 개체간의 유전적 차이로 한우육과 젖소육 혹은 수입육의 구별방법을 개발하기 위한 연구가 많이 수행되었다. 그 중 real-time PCR 판별방법은 기존 PCR의 단점인 허위양성을 배제시켜 그 결과의 신뢰성이 높으며, PCR 산물들의 제한효소에 의한 절단 및 겔에서의 확인 등의 과정을 생략시킬 수 있어 짧은 시간 내에 다량의 시료를 분석할 수 있고 민감도가 높아 쇠고기가 포함된 가공식품의 분석도 가능하다는 장점이 있다. 본 연구는 시중에서 한우로 유통되는 쇠고기(생육 또는 양념육)의 DNA를 추출하여 real-time PCR을 통해서 모색유전자의 유전자 형(C-type, C/T-type or T-type)으로 한우육과 젖소육 및 수입육을 구분하였다. 한우육만을 판매한다는 시중 음식점 41개소에서 쇠고기(생육 또는 양념육)를 수거하여 분석한 결과, 분석된 41개의 시료 중 29개가 한우 유전자형으로, 12개의 시료가 젖소 또는 수입육 유전자형으로 판별되었다. 따라서 분석된 시료들의 한우육(T-type) 비율은 $70.1\%$, 그리고 젖소육 또는 수입육 비율은 $29.3\%$(C/T-type; $12.2\%$, C-type; $17.1\%$)이었다.

• 한국가금학회지
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• 제40권2호
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• pp.139-145
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• 2013

본 연구는 '우리맛닭 실용계의 외모 균일화 및 판별 마커개발을 위하여 수탉으로 이용되는 토종닭 순계 H계통 암탉 207수, 수탉 40수와 '우리맛닭' 실용계 60수의 혈액을 채취하고 DNA를 분리하였다. 모색 관련 후보 유전자 MC1R primer를 제작하여 PCR을 수행한 후, direct sequencing을 실시하였다. 개체별 모색 표현형을 조사한 결과, H계통 순계 암탉 207수 중 157수는 흑색 모색, 50수는 흑색+갈색 모색으로 조사되었다. 수탉의 경우, 40수 중 흑색 모색만 있는 개체는 없고, 흑색+갈색의 모색이 다양한 부위에 섞여 있었다. '우리맛닭' 실용계의 경우 흑색 모색 30수와 갈색 모색 30수를 암수 관계없이 샘플링하여 조사하였다. 모색 표현형과 유전형과의 연관성을 알아보기 위하여 모색 관련 후보유전자 MC1R의 sequencing 결과를 분석하여 유전자 변이를 살펴보았지만, 모색 표현형과 유전형과의 유의적인 연관성을 찾을 수 없었다. 이는 토종닭 순계 H계통의 경우, 검정색의 같은 품종 내에서 갈색 이모색을 가진 개체와의 유전적 변이를 탐색한 결과, 그 차이가 분명하게 구별되지 않은 것으로 생각되어진다. '우리맛닭' 실용계에서 haplotype 및 유전자빈도 분석을 통하여 이모색과의 연관성을 보다 명확하게 결정하기 위해서는 부계와 모계의 모색 표현형과 유전특성을 함께 고려해야 할 것으로 판단된다. '우리맛닭'의 모색 균일도 향상을 위한 모색 표현형과 관련 유전자의 연관성분석 및 유전적 특성에 대한 연구는, 향후 이를 이용하여 '우리맛닭'의 불법 유통을 막고 고품질 브랜드화를 위한 분자마커 개발의 기초 자료로 활용될 것으로 생각된다.

• Journal of Forest and Environmental Science
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• 제36권3호
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• pp.225-232
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• 2020

Chemical modification of wood is an effective method to enhance the biological durability of wood with no toxic effect on the environment. In this study, wood of Triplochiton scleroxylon was modified using acetylation techniques. A total of one hundred wood blocks, (each 20×20×60 mm) obtained from a 22-year old T. scleroxylon tree were conditioned and acetylated at 120℃ in a bioreactor containing acetic anhydride for 60, 120, 180, 240 and 300 minutes. The percentage weight gain of acetylated wood was determined. The untreated (control) and treated blocks were exposed to Pleurotus ostreatus (white rot fungus) and Fibroporia vaillanti (brown rot fungus) after which moisture content (MC) and weight loss (WL) was monitored for 16 weeks. Data were analysed using descriptive and inferential statistics at p<0.05 level of significance. The percentage weight gain of acetylated wood samples increased with time from 10.4% (60 minutes) to 22.7% (300 minutes). MC of untreated blocks inoculated with Pleurotus ostreatus was significantly higher than those of Fibroporia vaillantii after 16 weeks exposure. There was no significant difference in the MC of the of the acetylated samples for the two fungi after 300 minutes reaction time. The WL of untreated blocks inoculated with Fibroporia vaillantii was higher than those of Pleurotus ostreatus, however, the two fungi showed no significant difference in the WL for the acetylated samples after 16 weeks exposure. Acetylation prevents moisture absorption and inhibition of fungi growth in acetylated wood compared to untreated wood, thereby enhancing the durability of Triplochiton scleroxylon.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.107-107
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• 1997

Cytochrome P450 enzymes have been intensively investigated in hepatic tissues and several mammalian cell lines. Compared to most studies about cytochrome P450 isozymes in liver in vivo and hepatic, cell lines in vitro, the study of cytochrome P450IA1 in human breast cancer cells could be very important to understand the mechanism of the regulation of CYPIA1 gene expression and cell growth. MCF-7 human breast cancer cells are well characterized to study estrogen and antiestrogen action due to the fact that they contain high level of estrogen receptor and have biological markers characterized. And also MCF-7 cells express high level of arylhydrocarbon hydroxylase activity and human cytochrome P450IA1 cDNA was cloned from MCF-7 cells. Ah receptor was characterized in many breast cancer cell lines and polycyclic aromatic hydrocarbon such as 3-MC induced the expression of CYPIA1 gene and cytochrome P450- dependent monooxygenase activity. We undertook a study to examine the effect of estrogens and other chemicals on the regulation of human CYPIA1 gene expression in MCF-7 cells via RTPCR analysis, that might help us to understand the mechanism of the regulation of CYPIA1 gene expression and MCF-7 cell growth. Expression vector containing the functional 5'-regulatory region of human CYPIA1 fused to the CAT reporter gene was transfected into estrogen receptor positive MCF-T cells or estrogen receptor negative MDA-MB-231 cells. After these cells were treated with various chemicals, RTPCR was carried out to measure both CYPIA1 mRNA and CAT mRNA levels. 1nM 3-MC increased in both P450 and CAT mRNA levels over those of control by two folds in MCF-7 cells but does not in MDA-MB-231 cells. Estrogen or tamoxifen or retinoic acid or chrysin decreased in both P450 and CAT mRNA levels that were induced by 3-MC in MCF-7 when each chemical was administered with 3-MC concomitantly. These results suggested that the level of CYPIA1 gene expression is modulated with estrogen-related molecules and make it possible to speculate that ER is related to CYPIA1 gene expression and cell growth in breast cancer cells. [Supported by grants from the Korean Ministry of Education ]

• 한국분말재료학회지
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• 제1권2호
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• pp.190-197
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• 1994

The densification behavior during a sintering of M2 and T15 grade high speed steel powder compacts was reported. Sintered densities over 98% theoretical were achieved by a liquid phase sintering in vacuum for both grades. The optimum sintering temperature range where full densification could be achieved without excessive carbide coarsening and incipient melting was much narrower in M2 than in T15 grade. The sintering response was mainly affected by the type of carbides present. The primary carbides in M2 were identified as $M_6C$ type whereas those in T15 were MC type which provides wider sintering range. The addition of elemental carbon up to 0.3% lowered the optimum sintering temperature for both grades, but had little effect on expanding the sintering range and sintered structure.