• Asian-Australasian Journal of Animal Sciences
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• 제14권6호
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• pp.880-884
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• 2001

Rumen microbiology research has undergone several evolutionary steps: the isolation and nutritional characterization of readily cultivated microbes; followed by the cloning and sequence analysis of individual genes relevant to key digestive processes; through to the use of small subunit ribosomal RNA (SSU rRNA) sequences for a cultivation-independent examination of microbial diversity. Our knowledge of rumen microbiology has expanded as a result, but the translation of this information into productive alterations of ruminal function has been rather limited. For instance, the cloning and characterization of cellulase genes in Escherichia coli has yielded some valuable information about this complex enzyme system in ruminal bacteria. SSU rRNA analyses have also confirmed that a considerable amount of the microbial diversity in the rumen is not represented in existing culture collections. However, we still have little idea of whether the key, and potentially rate-limiting, gene products and (or) microbial interactions have been identified. Technologies allowing high throughput nucleotide and protein sequence analysis have led to the emergence of two new fields of investigation, genomics and proteomics. Both disciplines can be further subdivided into functional and comparative lines of investigation. The massive accumulation of microbial DNA and protein sequence data, including complete genome sequences, is revolutionizing the way we examine microbial physiology and diversity. We describe here some examples of our use of genomics- and proteomics-based methods, to analyze the cellulase system of Ruminococcus flavefaciens FD-1 and explore the genome of Ruminococcus albus 8. At Illinois, we are using bacterial artificial chromosome (BAC) vectors to create libraries containing large (>75 kbases), contiguous segments of DNA from R. flavefaciens FD-1. Considering that every bacterium is not a candidate for whole genome sequencing, BAC libraries offer an attractive, alternative method to perform physical and functional analyses of a bacterium's genome. Our first plan is to use these BAC clones to determine whether or not cellulases and accessory genes in R. flavefaciens exist in clusters of orthologous genes (COGs). Proteomics is also being used to complement the BAC library/DNA sequencing approach. Proteins differentially expressed in response to carbon source are being identified by 2-D SDS-PAGE, followed by in-gel-digests and peptide mass mapping by MALDI-TOF Mass Spectrometry, as well as peptide sequencing by Edman degradation. At Ohio State, we have used a combination of functional proteomics, mutational analysis and differential display RT-PCR to obtain evidence suggesting that in addition to a cellulosome-like mechanism, R. albus 8 possesses other mechanisms for adhesion to plant surfaces. Genome walking on either side of these differentially expressed transcripts has also resulted in two interesting observations: i) a relatively large number of genes with no matches in the current databases and; ii) the identification of genes with a high level of sequence identity to those identified, until now, in the archaebacteria. Genomics and proteomics will also accelerate our understanding of microbial interactions, and allow a greater degree of in situ analyses in the future. The challenge is to utilize genomics and proteomics to improve our fundamental understanding of microbial physiology, diversity and ecology, and overcome constraints to ruminal function.

• 한국수산과학회지
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• 제30권1호
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• pp.46-54
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• 1997

분열효모 S. pombe의 포자형성은 배지상의 질소원의 고갈에 의하여 유도되어진다. 감수분열로부터 포자형성에 도달하는 과정에는 다수의 특이적인 유전자가 기능을 하고 있다. 본 연구에서는, 전포자막 구축에 필수적인 유전자 spo 5의 발현조절과 유전자의 메커니즘에 관하여 조사하였다. spo 5 유전자를 보유하는 약 5kb의 Hind III DNA 단편을 cloning 하였다. 이 단편으로부터 제한효소지도를 작성하여 얻어진 DNA 단편을 probe로 하여, RNA blot-hybridization를 이행하였다. 이 결과, 최소배지의 hetro matting-type 균주 (CD16-1)로 부터 조제한 mRNA가 검출되었다. 그리고 이 전사산물을 전사레밸에서 해석하기 위하여, homo matting-type (CD16-3) 균주를 질소원이 함유되지 않은 포자형성배지에서 배양한 후, 동일한 방법으로 mRNA를 조제하여 Northern hybridization으로 조사하였다. 그 결과, 이들 세포에서는 3.2kb에서만 전사산물이 검출되었으며, 2.5kb의 mRNA는 검출되지 않았다. 이상의 결과로 부터 spo 5 유전자를 coding하는 전사산물인 2.5kb의 mRNA는 질소원의 고갈된 상태하에서, 접합형 유전자좌의 hetro 접합성을 요구하는 것으로 입증하였다. spo 5 유전자의 전사발현은 질소원이 결핍과 접합형 유전자좌의 구성에 따른 환경요인과 유전적 요인에 의해서 제어되어지고 있다는 것을 입증하였다.

• 한국정보통신학회논문지
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• 제5권7호
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• pp.1332-1339
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• 2001

SoC(System on Chip) 기술은 높은 융통성을 제공하므로 실장제어 분야에서 널리 활용되고 있다. 실장제어 시스템은 소프트웨어와 하드웨어를 동시에 개발하여야 하므로 많은 시간과 비용이 소요된다. 이러한 설계시간과 비용을 줄이기 위해 고급언어 컴파일러에 적합한 명령어 세트를 가지는 마이크로프로세서가 요구된다. 또한 FPGA(Field Programmable Gate Array)에 의한 설계검증이 가능해야 한다. 본 논문에서는 소형 실장제어 시스템에 적합한 EISC(Extendable Instruction Set Computer) 구조에 기반한 16 비트 FPGA 마이크로프로세서인 EISC16을 제안한다. 제안한 EISC16은 짧은 길이의 오프셋과 작은 즉치값을 가진 16 비트 고정 길이 명령어 세트를 가진다. 그리고 16 비트 오프셋과 즉치 값은 확장 레지스터와 확장 플래그를 사용하여 확장한다. 또한, IBM-PC와 SUN 워크스테이션 상에서 C/C++ 컴파일러 빛 응용 소프트웨어를 설계하였다. 기존 16 비트 마이크로프로세서들의 C/C++ 컴파일러를 만들고 표준 라이브러리의 목적 코드를 생성하여 크기를 비교한 결과 제안한 EISC16의 코드 밀도가 높음을 확인하였다. 제안한 EISC16은 Xilinx의 Vertex XCV300 FPGA에서 RTL 레벨 VHDL로 설계하여 약 6,000 게이트로 합성되었다. EISC16은 ROM, RAM, LED/LCD 판넬, 주기 타이머, 입력 키 패드, 그리고 RS-232C 제어기로 구성한 테스트 보드에서 동작을 검증하였다. EISCl6은 7MHz에서 정상적으로 동작하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2915-2921
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• 2015

Background: Some recent clinical trials have been conducted to evaluate a combination of EGFR- TKI with chemotherapy for advanced NSCLC patients as second-line therapy, but the results on the efficacy of such trials are inconsistent. The aim of this meta-analysis was to evaluate the efficacy and safety of combination of EGFR-TKI and chemotherapy for patients with advanced NSCLC who failed first-line treatment. Materials and Methods: We searched relative trials from PubMed, EMBASE, ASCO Abstracts, ESMO Abstracts, Cochrane Library and Clinical Trials.gov. Outcomes analyzed were overall response rate (ORR), progression- free survival (PFS), overall survival (OS) and major toxicity. Results: Seven trails eventually were included in this meta-analysis, covering 1,168 patients. The results showed that the combined regimen arm had a significant higher ORR (RR 1.76 [1.16, 2.66], p=0.007) and longer PFS (HR 0.75 [0.66-0.85], p<0.00001), but failed to show effects on OS (HR 0.88 [0.68-1.15], p=0.36). In terms of subgroup results, continuation of EGFR-TKI in addition to chemotherapy after first-line EGFR-TKI resistance confered no improvement in ORR (RR 0.95 [0.68, 1.33], p=0.75) and PFS (HR 0.89[0.69, 1.15], p=0.38), and OS was even shorter (HR1.52 [1.05-2.21], p=0.03). However, combination therapy with EGFR-TKI and chemotherapy after failure of first-line chemotherapy significantly improved the ORR (RR 2.06 [1.42, 2.99], p=0.0002), PFS (HR 0.71 [0.61, 0.82], p<0.00001) and OS (HR 0.74 [0.62-0.88], p=0.0008), clinical benefit being restricted to combining EGFR-TKI with pemetrexed, but not docetaxel. Grade 3-4 toxicity was found at significantly higher incidence in the combined regimen arm. Conclusions: Continuation of EGFR-TKI in addition to chemotherapy after first-line EGFR-TKI resistance should be avoided. Combination therapy of EGFR-TKI and pemetrexed for advanced NSCLC should be further investigated for prognostic and predictive factors to find the group with the highest benefit of the combination strategy.

• BMB Reports
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• 제34권4호
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• pp.334-341
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• 2001

Even though three isotypes of thioredoxins (-f, -m and -h types) have been identified in a variety of plant cells, there are only a few reports on thioredoxin-h that were recently identified. In this study, a cDNA encoding a h-type of thioredoxin was isolated from a cDNA library of Chinese cabbage, and named here CTrx-h. An open reading frame of the gene contained a polypeptide of 133 amino acids with a conserved active center, WCGPC, which appeared in all of the thioredoxin proteins. A deduced amino acid sequence of the CTrx-h showed the highest sequence identity with those of Arabidopsis thioredoxin-h2 (75.2%) and thioredoxin-h5 (46.6%) proteins, but it shared a low sequence homology to other isotypes of plant thioredoxinm and thioredoxin-f. The CTrx-h protein that is expressed in E. coli represented not only an insulin reduction activity, but also electron transferring activity from NADPH to thioredoxin-dependent peroxidase. A genomic Southern blot analysis using the cDNA insert of CTrx-h revealed that the gene consisted of a small multigene family in Chinese cabbage genome. On the contrary to other thioredoxin-h proteins that were widely distributed in most tissues of the plant, the CTrx-h was predominantly expressed in flowers. The expression was very low in other tissues. The data of the Northern blot analysis suggests that the CTrx-h may have other functions in flower development or differentiation, in addition to its defensive role.

• 대한지역사회영양학회지
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• 제23권1호
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• pp.60-72
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• 2018

Objectives: This study was conducted to investigate the awareness of energy drinks, energy drink consumption behaviors, and associated factors among college students. Methods: A total of 536 students from three universities in Cheongju completed a self-administered questionnaire regarding awareness and consumption of energy drinks as well as general characteristics, health-related characteristics, and eating habits. Results: Approximately half of the respondents reported they knew what energy drinks were, while 45.7% had heard of energy drinks but did not know what they were. However, 76.9% had experience in using energy drinks. The main reason for using energy drinks was to stay awake, and the main place that they were used was on campus or at the library. More than 70% of energy drink users did not read the caffeine contents of energy drinks. After consuming energy drinks, 31.3% experienced adverse effects, the most serious being sleep disturbance. Approximately 33% of students consumed energy drinks once a month or more frequently, and men consumed energy drinks more frequently than females. Energy drink users who consumed at least one drink each month were more likely to be natural science major or drink more milk for male students, and to have more allowances or consume less meat for female students, compared with non-users. Conclusions: Our study showed that 33% of students consumed at least one energy drink each month, and there were a small number of students consumed energy drinks almost every day or energy drinks mixed with alcohol. Accordingly, college students should be taught potential health hazards of energy drinks mixed with alcohol as well as energy drinks alone. In addition, reading labels about caffeine and sugar contents in energy drinks is encouraged.

• 대한화장품학회지
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• 제36권3호
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• pp.233-240
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• 2010

신규 미백 소재 개발을 위하여 tyrosinase의 활성을 억제하는 천연물과, alpha-melanocyte stimulating hormone ($\alpha$-MSH)을 저해하는 펩타이드를 결합한 소재를 고체상 합성법으로 제조하였다[1,2]. Tyrosinase 활성 억제 효능이 있는 천연유래물질을 기존 연구를 바탕으로 선정하였으며, 이중에서 상업화 된 물질 17종에 대해 Mushroom Tyrosinase 활성 억제 효과를 측정하여, 그 중 caffeic acid, coumaric acid를 선별하였다. 펩타이드는 $\alpha$-MSH 분비를 억제하며, tyrosinase활성을 억제하는 것으로 알려진 melanostatin을 선정하였으며[3-5], PLG-$NH_2$ (Proline-Leucine-Glycine-$NH_2$) 중에서 유도체화 수율의 저하 원인으로 예상되는 Proline (Pro)의 서열을 다른 아미노산으로 변경하면서 선별된 천연물인 coumaric acid와 caffeic acid에 도입하였다. 또한 최종물질의 원가를 고려하여 acid-amide 형태를 acid형태로 전환한 유도체를 합성하였다. 이들 펩타이드 유도체들에 대해서 B16F1 melanoma cell에서의 멜라닌 생성 억제 효능을 평가하여 유도체화된 물질이 기존의 천연유래물질이나 펩타이드에 비하여 높은 저해효과를 가지는 것을 확인하였다.

• Molecules and Cells
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• 제20권3호
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• pp.385-391
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• 2005

As a first step towards identifying genes involving in the signal transduction pathways mediating rice blast resistance, we isolated 3 mutants lines that showed enhanced susceptibility to rice blast KJ105 (91-033) from a T-DNA insertion library of the japonica rice cultivar, Hwayeong. Since none of the susceptible phenotypes co-segregated with the T-DNA insertion we adapted a map-based cloning strategy to isolate the gene(s) responsible for the enhanced susceptibility of the Hwayeong mutants. A genetic mapping population was produced by crossing the resistant wild type Hwayeong with the susceptible cultivar, Nagdong. Chi-square analysis of the $F_2$ segregating population indicated that resistance in Hwayeong was controlled by a single major gene that we tentatively named Pi-hy. Randomly selected susceptible plants in the $F_2$ population were used to build an initial map of Pi-hy. The SSLP marker RM2265 on chromosome 2 was closely linked to resistance. High resolution mapping using 105 $F_2$ plants revealed that the resistance gene was tightly linked, or identical, to Pib, a resistance gene with a nucleotide binding sequence and leucine-rich repeats (NB-LRR) previously isolated. Sequence analysis of the Pib locus amplified from three susceptible mutants revealed lesions within this gene, demonstrating that the Pi-hy gene is Pib. The Pib mutations in 1D-22-10-13, 1D-54-16-8, and 1C-143-16-1 were, respectively, a missense mutation in the conserved NB domain 3, a nonsense mutation in the 5th LRR, and a nonsense mutation in the C terminus following the LRRs that causes a small deletion of the C terminus. These findings provide evidence that NB domain 3 and the C terminus are required for full activity of the plant R gene. They also suggest that alterations of the resistance gene can cause major differences in pathogen specificity by affecting interactions with an avirulence factor.

• Journal of Plant Biotechnology
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• 제33권2호
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• pp.85-91
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• 2006

Flavanone 3$\beta$-hydroxylase (FHT)는 flavonoid 생합성 경로의 가장 중심부에 작용하는 효소로 flavanone으로부터 dihydroflavonol으로의 변환을 촉매하는 역할을 한다. 본 연구에서는 색소유전자의 전이를 통하여 새로운 색소발현체계를 가진 품종을 육종하기 위한 기초연구로 숙성안개초 (Gypsophila paniculata L.)의 꽃봉오리로부터 cDNA-library를 합성하였고 카네이션의 FHT 유전자를 probe로 사용하여 anthocyanin 합성경로의 중요 효소의 하나인 FHT 유전자를 분리하였다. 염기서열분석을 수행하여 분리유전자의 크기가 1471 bp 이며 이 중 coding region은 1047 bp 임을 확인하였다. 이미 밝혀진 다른 식물체의 FHT 유전자와 서로 염기서열의 일치성을 비교해 본 결과 아라비돕시스, 오렌지, 카네이션, 고구마, 스톡, 페튜니아, 감자 및 포도에서 각각 69% 이상을 나타내었다. 분리유전자의 발현을 확인하기 위하여 Northern blot분석 및 인위적으로 기내에서의 transcription과 translation을 수행하였고, 분리한 유전자의 효소활성을 측정해 본 결과 dihtydrokaempferol의 작은 peak을 확인하였다. Southern blot 분석의 결과 안개초의 FHT 유전자는 다른 대부분의 식물체와 유사하게 한 개가 존재함을 확인하였다

• 대한지역사회작업치료학회지
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• 제5권2호
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• pp.43-55
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• 2015

목적 : 본 연구는 대학생의 우울을 연구한 선행 연구들을 바탕으로 우울에 대한 요인을 통합적으로 살펴보고자 한다. 이를 통하여 한국 대학생의 우울을 감소시키기 위한 실천 방향을 제시하고자 한다. 연구방법 : 2000년부터 2014년까지 게재된 국내논문을 연구 분석자료로 활용하였다. 자료 수집은 국가과학기술정보센터(NDSL), 누리미디어(DBpia), 한국학술정보(KISS), 학술연구정보서비스(RISS), 국회도서관의 원문 제공 서비스를 이용하여 2,558개 논문이 수집되었다. 주요 검색용어(Key words)는 '대학생, 우울, 우울요인' 있고 논문의 질적 수준을 평가하기 위해 Down & Black(1998)에 의해 개발된 연구의 근거기반수준 체크리스트를 사용하였다. 최종적으로 선정된 문헌들을 메타분석 하였다. 결과 : 최종 분석에 사용된 47편의 연구들을 5개의 요인군(자아존중감, 자살사고, 긍정적사고, 스트레스, 인터넷과 스마트폰 중독)으로 나누었다. 각 요인군에 대하여 메타분석을 사용하여 통계적 이질성, 효과크기, 출판편의를 분석하였다. 그 결과 5개의 요인 중 자아존중감은 이질성이 발견되지 않았다. 효과크기는 자아존중감과 자살사고가 큰 효과 크기가 있었고, 긍정적사고와 스트레스는 중간 효과크기이며, 인터넷 및 스마트폰 중독은 작은 효과크기가 있는 것으로 분석되었다. 결론 : 한국 대학생들의 우울을 예방하기 위해서는 자아존중감을 높이고 자살에 대한 사고를 줄일 수 있는 다양한 지원이 이루어져야 할 것이다.