• BMB Reports
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• 제34권6호
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• pp.502-508
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• 2001

A cDNA, encoding the human growth hormone (hGH), was synthesized based on the known 191 amino acid sequence. Its codon usage was optimized for a high level expression in Escherichia coli. Unique restriction sites were incorporated throughout the gene to facilitate mutagenesis in further studies. To minimize an initiation translation problem, a 624-bp cassette that contained a ribosome binding site and a start codon were fused to the hGH-coding sequence that was flanked between the EcoRI and HindIII sites. The whole fragment was synthesized by an overlapped extension of eight long synthetic oligonucleotides. The four-short duplexes of DNA, which were first formed by annealing and filling-in with a Klenow fragment, were assembled to form a complete hGH gene. The hGH was cloned and expressed successfully using a pET17b plasmid that contained the T7 promoter. Recombinant hGH yielded as much as 20% of the total cellular proteins. However, the majority of the protein was in the form of insoluble inclusion bodies. N-terminal amino acid sequencing also showed that the hGH produced in E. coli contained formyl-methionine. This study provides a useful model for synthesis of the gene of interest and production of recombinant proteins in E. coli.

• BMB Reports
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• 제47권3호
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• pp.173-178
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• 2014

There is rapidly growing interest in the human microbiome because of its implication in metabolic disorders and inflammatory diseases. Consequently, understanding the biology of short chain fatty acids and their receptors has become very important for identifying novel therapeutic avenues. GPR41 and GPR43 have been recognized as the cognate receptors for SCFAs and their roles in metabolism and inflammation have drawn much attention in recent years. GPR43 is highly expressed on immune cells and has been suggested to play a role in inflammatory diseases such as inflammatory bowel disease. Both GPR41 and GPR43 have been implicated in diabetes and obesity via the regulation of adipose tissue and gastrointestinal hormones. So far, many studies have provided contradictory results, and therefore further research is required to validate these receptors as drug targets. We will also discuss the synthetic modulators of GPR41 and GPR43 that are critical to understanding the functions of these receptors.

• 생명과학회지
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• 제27권10호
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• pp.1130-1136
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• 2017

본 연구에서는 장수풍뎅이 유충 추출물을 이용하여 알레르기 및 염증 반응에 미치는 효과를 확인하였다. 장수풍뎅이 유충 추출물의 항알레르기와 항염증 효능은 Compound 48/80에 의해 활성화된 비만세포(RBL-2H3)와 lipopolysaccharide(LPS)로 활성화된 대식세포(Raw 264.7)로부터 분비 또는 발현되는 ${\beta}-hexosaminidase$, $TNF-{\alpha}$, IL-4, IL-6, COX-2, nitric oxide, 및 iNOS를 측정하여 관찰하였다. 비만세포에 장수풍뎅이 유충 추출물과 Compound 48/80을 함께 처리한 경우 비만세포의 탈과립에 의해서 분비되는 ${\beta}-hexosaminidase$의 양이 현저히 감소하였으며 $TNF-{\alpha}$, IL-4, COX-2의 발현 또한 효과적으로 감소시킴을 확인할 수 있었다. 또한 LPS에 의해 활성화된 대식세포(Raw 264.7)는 장수풍뎅이 유충 추출물 처리에 의해 염증반응인자인 IL-6와 nitric oxide의 분비량이 현저히 감소함을 확인할 수 있었다. 이상의 결과는 장수풍뎅이 유충 추출물이 알레르기와 염증반응의 원인 물질인 ${\beta}-hexosaminidase$ 억제 효과뿐만 아니라, 염증 cytokine의 발현을 저해하는 것으로 보아 알레르기와 염증 질환의 예방과 치료에 효과적으로 이용될 수 있음을 확인할 수 있었다.

• 과학교육연구지
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• 제42권1호
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• pp.12-26
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• 2018

본 연구에서는 과학기술과 관련된 사회적 쟁점에 대한 논증 프로그램을 통해 예비 생물교사들의 의사결정 유형과 의사소통 능력의 변화를 살펴보았다. 또한 의사결정 유형과 의사소통 능력의 상관관계를 조사하고, 예비생물 교사들은 SSI 논증 프로그램 후 의사소통 및 의사결정에 관해 어떠한 경험을 하였는지 살펴보았다. SSI 논증 프로그램은 사회적 의사결정과 문제해결전략을 활용하여 개발되었으며, 낙태, 안락사, 유전자 조작 및 인공지능을 주제로 총 12차시에 걸쳐 진행되었다. 예비교사들은 SSI 문제를 파악하고, 해결책을 생각하며, 최선의 방안을 결정하도록 하였으며, 이 과정에서 소집단 토론을 통해 사회과학적 문제에 대한 논증 활동의 기회를 가졌다. 연구 결과, 예비 교사들의 의사소통 능력은 통계적으로 유의미한 향상을 나타냈으나, 의사결정 유형에는 변화가 없었다. 또한 Pearson 상관 분석 결과, 의사결정 유형 중 '합리적 유형'은 의사소통 능력과 유의미한 상관관계를 나타냈다. 예비교사들은 사회과학적 쟁점에 대한 논증 프로그램을 통해 근거, 자료, 맥락, 반론 등을 고려하여 자신의 주장을 말하는 능력이 향상되었다고 언급하였다. 또한 사회과학적 문제에 관심을 가지게 되고 다른 사람의 비판을 수용할 수 있게 되었을 뿐만 아니라 자신도 다른 사람을 배려하면서 자신의 의견을 말할 수 있게 되었다고 하여 과학교육에서 SSI 논증 활동을 통한 인성 교육의 가능성을 시사한다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권5호
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• pp.640-647
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• 2008

Breed differences in adult animals are determined during fetal development. If interventions are to be developed that influence growth of muscle and fat, it is important to know at which time during gestation breed differences appear and are fixed. The objective of this study was to characterize fetal development in cattle of different breeds. Pregnant cows of 4 cattle breeds with different growth impetus and muscularity were slaughtered under normal processing conditions and the fetuses were removed. German Angus, a typical beef cattle; Galloway, a smaller, environmentally resistant beef type; Holstein Friesian, a dairy type; and Belgian Blue, an extreme type for muscle growth were used. Fetuses of each breed were investigated at 3, 6, and 9 mo of gestation. Fetuses were weighed and dissected into carcass, organs, and muscles. Body fat weight was obtained using the Soxhlet extraction method. Fetal weight increased most rapidly in the third trimester of gestation mainly due to the accelerated muscle and fat deposition. The organ weight to body weight (BW) ratios decreased and the muscle and fat weight to BW ratios increased. At 3 mo of gestation, Galloway fetuses had the significantly smallest BW, half-carcass weight, leg weight, organ weight, muscle weight and shortest leg length. In contrast, Holstein fetuses had the significantly greatest BW, liver, kidney, and lung weights and significantly longest leg length among the 4 breeds, but no differences between Holstein Friesian and Belgian Blue were detected in half-carcass and leg weight. Indeed, Belgian Blue fetuses had the significantly greatest half-carcass weight, leg weight, and muscle weight at 9 mo of gestation, and Galloway had a significantly greater body fat to BW ratio than Holstein Friesian and Belgian Blue. These differences were not evident at 3 and 6 mo of gestation. These data show that the profound increase of tissue and organ weights occurred in later gestation in cattle fetuses even though breed differences were evident as early as 3 mo of gestation. Depending on the tissue of interest, impacting fetal growth likely needs to occur early in gestation before the appearance of breed-specific differences.

• Genomics & Informatics
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• 제5권2호
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• pp.46-55
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• 2007

The convergence of molecular and genetic disciplines with non-invasive imaging technologies has provided an opportunity for earlier detection of disease processes which begin with molecular and cellular abnormalities. This emerging field, known as molecular imaging, is a relatively new discipline that has been rapidly developed over the past decade. It endeavors to construct a visual representation, characterization, and quantification of biological processes at the molecular and cellular level within living organisms. One of the goals of molecular imaging is to translate our expanding knowledge of molecular biology and genomic sciences into good patient care. The practice of molecular imaging is still largely experimental, and only limited clinical success has been achieved. However, it is anticipated that molecular imaging will move increasingly out of the research laboratory and into the clinic over the next decade. Non-invasive in vivo molecular imaging makes use of nuclear, magnetic resonance, and in vivo optical imaging systems. Recently, an interest in Positron Emission Tomography (PET) has been revived, and along with optical imaging systems PET is assuming new, important roles in molecular genetic imaging studies. Current PET molecular imaging strategies mostly rely on the detection of probe accumulation directly related to the physiology or the level of reporter gene expression. PET imaging of both endogenous and exogenous gene expression can be achieved in animals using reporter constructs and radio-labeled probes. As increasing numbers of genetic markers become available for imaging targets, it is anticipated that a better understanding of genomics will contribute to the advancement of the molecular genetic imaging field. In this report, the principles of non-invasive molecular genetic imaging, its applications and future directions are discussed.

• Journal of Microbiology and Biotechnology
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• 제31권3호
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• pp.387-397
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• 2021

There is growing interest in the production of microalgae-based, high-value by-products as an emerging green biotechnology. However, a cultivation platform for Oocystis sp. has yet to be established. We therefore examined the effects of bacterial culture additions on the growth and production of valuable compounds of the microalgal strain Oocystis sp. KNUA044, isolated from a locally adapted region in Korea. The strain grew only in the presence of a clear supernatant of Sphingomonas sp. KNU100 culture solution and generated 28.57 mg/l/d of biomass productivity. Protein content (43.9 wt%) was approximately two-fold higher than carbohydrate content (29.4 wt%) and lipid content (13.9 wt%). Oocystis sp. KNUA044 produced the monosaccharide fucose (33 ㎍/mg and 0.94 mg/l/d), reported here for the first time. Fatty acid profiling showed high accumulation (over 60%) of polyunsaturated fatty acids (PUFAs) compared to saturated (29.4%) and monounsaturated fatty acids (9.9%) under the same culture conditions. Of these PUFAs, the algal strain produced the highest concentration of linolenic acid (C18:3 ω3; 40.2%) in the omega-3 family and generated eicosapentaenoic acid (C20:5 ω3; 6.0%), also known as EPA. Based on these results, we suggest that the application of Sphingomonas sp. KNU100 for strain-dependent cultivation of Oocystis sp. KNUA044 holds future promise as a bioprocess capable of increasing algal biomass and high-value bioactive by-products, including fucose and PUFAs such as linolenic acid and EPA.

• 과학교육연구지
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• 제34권2호
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• pp.268-278
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• 2010

본 연구에서는 단백질 합성 과정을 효과적으로 학습하기 위한 단백질 합성 과정 종이 모형을 개발하여 고등학교 생물 수업에서 그 교육적 효과를 알아보고자 하였다. 교육적 효과를 알아보기 위해 대전에 위치한 고등학교 2학년 117명을 대상으로 적용하였다. 실험 집단(59명)은 본 연구에서 개발한 단백질 합성 과정 종이 모형을 활용한 수업을 적용하였으며 통제 집단(58명)은 전통적 설명식 수업을 적용하였다. 그 결과 단백질 합성 과정 종이 모형을 적용 수업의 학생들의 학업성취도 향상 효과가 있었으며 학습 흥미 또한 향상된 것으로 나타났다. 단백질 합성 과정과 같이 추상적이거나 비가시적이어서 이해하기 어려운 학습 내용의 경우 종이 모형과 같은 구체적 경험을 활용한 수업을 활용하는 것이 효과적인 것을 알 수 있었다. 또한 이러한 학습 내용에 적절하면서도 흥미를 유발할 수 있는 새로운 모형 개발과 더불어 학교 현장에서 이를 적극 활용할 수 있도록 하기 위한 방안이 필요하다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권2호
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• pp.244-257
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• 2000

Recent progress in molecular biology has made it possible to transfer genes of interest into cells and target tissues of living animals. This enables one to manipulate phenotype of cells and whole animals in selected and intended ways. The consequence of such gene transfer attempts have been the production of various types of "transgenic" animals that cannot be classified by classical nomenclature of exclusively either "transgenic" or "nontransgenic". Emphasis was placed on characterizing two transgenic categories, i.e., "transfectgenic and somatotransgenic" and "genuine transgenic" animals basically from a view point of their use for therapeutic purposes. Current state of art and possible solutions for problems encountered at present are discussed.

• 한국제4기학회지
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• 제17권2호
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• pp.39-41
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• 2003

Pollen and spores as well as their morphological characteristics are biological stability materials in which contains historical information about vegetation and climate changes. As noted researcher Neishtadt in 1971, the lake and swamp deposits were developed only in Holocene period. The geological history of Darkhad depression which is situated in the Northern end of Mongolia from ancient time become under scientific interest of many researchers. Our investigation was focused on pollen analysis of lake sediment of Darkhad depression which caused bottom of paleolake. In Mongolia the palynology science is beginning to develop since 1990 and in 2000 the laboratory of palynology was established at the department of Biology, State Pedagogical University of Mongolia. Researchers from this laboratory working on pollen morphology of present flora in order to classify plants taxonomy. Another part of our investigation is mellitopalynology, which is studying of pollen grains in a honey. Although, this research has been extending by pollen analysis of sediment and lake deposits in past few years on the basis of high sensitive microscope and modem technology.