• KSBB Journal
• /
• 제20권2호
• /
• pp.93-99
• /
• 2005

불포화지방산의 생합성능이 뛰어나다고 알려진 Thraustochytrids 균주 중 26185를 대상으로 arachidonic acid (AA C20:4 n-6)를 포함하는 PUFA 생산에 관여하는 유전자의 하나로서 key enzyme인 desaturase를 보다 효율적이고 안정적인 방법으로 cloning한 후 결과물을 분석하였다. 이를 위해 실험균주인 26185 균주를 대상으로 효율적인 전체 nucleic acids 추출법을 개발하였으며 관련된 기법의 활용을 통해 일반적으로 활용이 가능한 효과적이 방법임을 확인하였다. 확보된 유전체를 통한 direct PCR의 결과물을 기존에 알려진 cDNA 합성방법에 의한 결과물과 비교하였을 때 동일한 결과물임을 확인하였다. 이는 Thraustochytrids 관련 균주로부터 지방산 생합성에 관련된 효소군을 탐색하는 방법이 cDNA 합성방법에 의하지 않고 보다 직접적으로 진행될 수 있음을 제안할 수 있는 하나의 결과물로 생각되어진다. 획득된 유전자를 같은 진핵세포인 P. pastoris를 숙주로 하여 유전자를 도입하고 활성을 재현성 있게 규명함으로써 인공진화 혹은 재조합균체의 개발이 가능하다는 사실을 부분적으로 제시할 수 있었다.

• Archives of Pharmacal Research
• /
• 제28권3호
• /
• pp.335-342
• /
• 2005

The effects of ginsenosides Rg$_3$(R) , Rg$_3$(S) and Rg$_5$/Rk$_1$ (a mixture of Rg$_5$ and Rk$_1$ 1:1, w/w), which are components isolated from processed Panax ginseng C.A. Meyer (Araliaceae), on memory dysfunction were examined in mice using a passive avoidance test. The ginsenosides Rg3(R), Rg3(S) or Rg$_5$/Rk$_1$, when orally administered for 4 days, significantly ameliorated the memory impairment induced by the single oral administration of ethanol. The memory impairment induced by the intraperitoneal injection of scopolamine was also significantly recovered by ginsenosides Rg3(S) and Rg$_5$/Rk$_1$. Among the three ginsenosides tested in this study, Rg$_5$/Rk$_1$ enhanced the memory function of mice most effectively in both the ethanol­and scopolamine-induced amnesia models. Moreover, the latency period of the Rg$_5$/Rk$_1$­treated mice was 1.2 times longer than that of the control (no amnesia) group in both models, implying that Rg$_5$/Rk$_1$ may also exert beneficial effects in the normal brain. We also evaluated the effects of these ginsenosides on the excitotoxic and oxidative stress-induced neuronal cell damage in primary cultured rat cortical cells. The excitotoxicity induced by glutamate or N­methyl-D-aspartate (NMDA) was dramatically inhibited by the three ginsenosides. Rg$_3$(S) and Rg$_5$/Rk$_1$ exhibited a more potent inhibition of excitotoxicity than did Rg$_3$(R). In contrast, these ginsenosides were all ineffective against the H$_2$O$_2$- or xanthine/xanthine oxidase-induced oxidative neuronal damage. Taken together, these results indicate that ginsenosides Rg$_3$(S) and Rg$_5$/Rk$_1$ significantly reversed the memory dysfunction induced by ethanol or scopolamine, and their neuroprotective actions against excitotoxicity may be attributed to their memory enhancing effects.

• 미생물학회지
• /
• 제46권2호
• /
• pp.122-126
• /
• 2010

RAD53은 효모의 검문지점 경로가 DNA 손상을 감지하여 여러 가지 후속적인 세포 내 반응을 일으키는 데 핵심적인 역할을 하는 인산화 효소일 뿐만 아니라, dNTP 생성에 중요한 RNR 유전자 등의 전사 활성화 과정에도 관여하는 효모의 생존에 필수적인 유전자이다. 본 연구에서는 rad53${\Delta}$ 돌연변이의 hydroxyurea에 대한 민감성을 억제하는 억제자로서 CYC8을 동정하였다. CYC8 유전자가 많은 사본으로 존재할 때 rad53${\Delta}$ 균주의 hydroxyurea에 대한 내성이 증가하였으나, CYC8과 복합체로 작용하는 TUP1은 다사본 억제자로 작용하지 못하였다. 반면, 삭제 돌연변이의 경우, cyc8${\Delta}$과 tup1${\Delta}$ 모두 억제자로 작용하였다. CYC8은 효모에서 프리온 단백질로 작용하기 때문에 과량 발현되면 정상적인 CYC8 단백질의 잘못된 접힘을 유발하게 되고, 결과적으로 우성의 $cyc8^-$ 표현형이 나타나게 된다. 따라서 CYC8이 다사본 억제자로 작용하는 이유는 이러한 프리온의 특성 때문으로 추측된다. CYC8이 다사본이거나 cyc8${\Delta}$ 돌연변이일 경우 모두 RNR 유전자의 전사가 증가되는 것을 관찰하였다. 따라서 CYC8에 의한 rad53${\Delta}$ 돌연변이의 억제는 RNR 증가에 따른 세포 내 dNTP 증가 때문으로 생각된다.

• Food Science and Biotechnology
• /
• 제15권1호
• /
• pp.122-127
• /
• 2006

The effects of fermented chaga mushroom (Inonotus obliquus) powder on the lipid concentrations and the activities of liver marker enzymes of serum in genetically diabetic Otsuka Long-Evans Tokushima fatty (OLETF) rats were investigated. Rats were fed a semisynthetic diet supplemented with 50 g/kg chaga mushroom powder (CM) or 50 g/kg fermented chaga mushroom powder (FCM) for 8 weeks (26 to 34 weeks of age). Nondiabetic Long-Evans Toknshima Otsuka (LETO) rats were used as age-matched nondiabetic control animals. Water consumption was significantly higher in the OLETF control than the LETO rats. Water consumption in the FCM-fed OLETF rats tended to be less than in both the OLETF control and CM-fed OLETF rats. Serum concentrations of triglycerides and total cholesterol were significantly higher in the OLETF control rats than in the LETO rats while within the OLETF rat groups, the consumption of FCM resulted in a significantly lower serum triglyceride concentration and slightly lowered serum total cholesterol concentration when compared to the OLETF control and CM-fed rats. The alanine aminotransferase (ALT) activity was significantly higher in the OLETF control than in the LETO rats, but this difference was significantly reduced compared to the CM-fed rats and essentially no difference in the ALT levels was observed between the LETO and OLETF-FCM rats. This observation suggests an adaptive effect of the fermented chaga mushroom in liver function. Livers of the LETO rats showed no histopathological changes, whereas those of the OLETF control rats were characterized by many fat depositions in the central zone of the hepatocytes. The livers of the OLETF CM-fed rats showed less fatty changes compared to the OLETF control rats and fat deposition in the hepatocytes was nearly absent. These results suggest that orally ingested fermented chaga mushroom has a potential beneficial effect on the complications known to occur in the obesity-related non-insulin dependent diabetes mellitus (NlDDM) OLETF rat.

• 한국통신학회논문지
• /
• 제38C권7호
• /
• pp.630-642
• /
• 2013

이동환자의 생체진단신호 원격전달을 위해서는 환자 및 감시자의 이동성, 환자의 이상징후 감지기능과 관련 컴퓨팅 자원들의 자율군집성 동작 서비스 바인딩 기능이 필수적으로 요구된다. 기존의 연구는 이동 환자 생체 신호 전달을 위해 중앙 집중화된 방식으로 중앙 서버 스스로 단일 고장점(Single Point of Failure)이 되어 서버가 다운되면 전체 시스템이 멈추게 되고, 지역적으로 일어나는 서비스에 대해 중앙으로 데이터 트래픽을 발생시킨다. 오버레이 네트워크 기반 자율군집형 미들웨어 플랫폼은 자율군집 메커니즘을 적용하여 구성한 유무선 이기종망 환경하의 오버레이 네트워크를 통해 관리 서버에 의한 중앙 또는 외부의 제어 없이 노드 간 협업에 의해 다양한 센서 장치(생체신호 측정 장비 포함)와 스마트폰, TV, PC 및 외부 시스템 간에 실시간 스트림 데이터를 송수신할 수 있도록 개발된 미들웨어 플랫폼이다. 생체신호 측정 장비로부터 발생한 여러 생체진단신호를 도처에 존재하는 자율군집형 분산 미들웨어 플랫폼인 SoSpR(Self-organizing Software-platform Router)로 관리 서버의 중재없이 자율적으로 실시간 전달 및 저장하고 동시에 복수개의 다양한 수신 단말에서 가까운 SoSpR로부터 실시간 수신 및 재생 시킬 수 있다.

• 한국제4기학회지
• /
• 제11권1호
• /
• pp.57-68
• /
• 1997

Climatic change of the late-Quaternary period has been record-ed in the loess deposits of the central Great plains and the record of such change is extractable using a number of approaches and parameters. The stratigraphy of loess deposits which have been investigated on Fort Riley exhibits the same sequence of loess units and intercalated buried soils as is found elsewhere in the re-gion but adds detail unique to the reservation Upland late-Qua-ternary composite stratigraphy preserved on the reservation con-sists of the basal Sangamon soil of the Last interglacial(c. 120-110ka), Gilman Canyon Formation(c. >40 -20ka), Peoria loess(c. 20 -10ka) Brady soil(c. 11 -10ka) Bignell loess(c. 9-\ulcornerka). and mod-ern surface soil. Application of magnetic analyses has provided proxy data sets that represent a time series of climatically regulated pedogenesis/weathering and botanical composition. magetic data have yielded an impression of the variation in climate from Sangamon time to the late Holocene through a reconstruction of the history of pedogenesis/weathering. Sangamon soil formation dominated the reservation durin the Last interglacial as indicated by magnetic parameters. During Gil-man Canyon time loess influx was usually sufficiently slow as to permit pedogenesis which appears to have been at a maximum twice during that time. Warm season grasses were important dur-ing soil formation but diminished in importance during the peri-ods of more rapid loess fall which were cooler and perhaps wet-ter. Peoria loess fall a function of the deterioration of climate during the last Glacial Maximum thinly blanketed the reservation with thickest accumulations occurring to the north-west(Bala Cemetery site)proximal to the source region. Long-term surface stability did not apparently occur within Peoria time but short-term stability may be indicaed by the presence of thin weathering zones(incipient soils) in the Peoria loess. Re-gional landscape stability prevailed during the environmental shift at the Pleistocene/Holocene transition resulting in forma-tion of the well expressed Brady soil. One or more weak soils developed in the Bignell loess as it ac-cumulated. A notable feature of the Bignell loess is the appear-ance of the Altithermal dry period: the loess experienced little weathering and was dominated by warm season grasses until the latter of the Holocene.

• 한국지역지리학회지
• /
• 제5권2호
• /
• pp.119-132
• /
• 1999

경남 남해안의 사천만 연안은 경남 서부지역의 관문 역할을 수행하였고, 그로 인해 군사적 요충지로 간주되었으며, 갯벌이 넓고 각종 수산자원이 풍부하여 일직부터 양식업과 어로업이 활발하였다. 이와 같이 사천만 연안은 역사적으로 경남 서부지역에서 해상교통 및 군사적 요충지, 또한 수산업이라는 기능면에서 매우 중요한 역할을 수행하여 왔다. 그런데 오늘날 사천만 연안에는 공항과 고속도로가 확충되어 항공 육상교통의 기능이 중요하게 부상하고 있고, 공단이 조성되어 많은 제조업체들이 입지함으로써 공업기능이 새로운 기능으로 대두되고 있다. 또한 사천만 연안의 육상 및 항공교통 발달은 지역의 관광자원개발을 좀 더 구체화시키고 있다. 지역의 전통적 기능들이 쇠퇴하는 대신에 공업, 교통, 관광 등 새로운 기능들이 중요하게 대두되고 있는 것이다. 따라서 사천만 연안 지역이 급격한 지역 변화를 경험하고 있음에 틀림없다. 본 연구의 연구목적은 이 지역에서 급격하게 진행되고 있는 교통 군사 수산업 관광 공업 기능의 변화 과정을 동태적으로 분석 정리함으로써 지역의 특성을 구명하는 데 있다. 특히 본 논문은 이 지역의 전통적 기능들과 오늘날 부상하고 있는 다양한 기능들을 밀접한 관련하에서 이해할 수 있음을 서술적으로 밝히고 있다.

• The Korean Journal of Physiology and Pharmacology
• /
• 제19권5호
• /
• pp.389-399
• /
• 2015

Zinc has been considered as a vital constituent of proteins, including enzymes. Mobile reactive zinc ($Zn^{2+}$) is the key form of zinc involved in signal transductions, which are mainly driven by its binding to proteins or the release of zinc from proteins, possibly via a redox switch. There has been growing evidence of zinc's critical role in cell signaling, due to its flexible coordination geometry and rapid shifts in protein conformation to perform biological reactions. The importance and complexity of $Zn^{2+}$ activity has been presumed to parallel the degree of calcium's participation in cellular processes. Whole body and cellular $Zn^{2+}$ levels are largely regulated by metallothioneins (MTs), $Zn^{2+}$ importers (ZIPs), and $Zn^{2+}$ transporters (ZnTs). Numerous proteins involved in signaling pathways, mitochondrial metabolism, and ion channels that play a pivotal role in controlling cardiac contractility are common targets of $Zn^{2+}$. However, these regulatory actions of $Zn^{2+}$ are not limited to the function of the heart, but also extend to numerous other organ systems, such as the central nervous system, immune system, cardiovascular tissue, and secretory glands, such as the pancreas, prostate, and mammary glands. In this review, the regulation of cellular $Zn^{2+}$ levels, $Zn^{2+}$-mediated signal transduction, impacts of $Zn^{2+}$ on ion channels and mitochondrial metabolism, and finally, the implications of $Zn^{2+}$ in health and disease development were outlined to help widen the current understanding of the versatile and complex roles of $Zn^{2+}$.

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

• 농촌지도와개발
• /
• 제10권2호
• /
• pp.267-283
• /
• 2003

The purposes of the study were to; 1) examine the diffusion and adoption of new agricultural technology in rice farming, 2) survey the status of agricultural education institutions on technology transfer, and 3) explore the linkages between agricultural education and extension for more effective reinforcement strategies to further the diffusion and adoption of new agricultural technology in Korea. Literature review, field survey and panel discussions were employed to strengthen the linkages among agricultural education, research and extension in Korea. As the results of analysis of the diffusion and adoption of new agricultural technology in rice farming following recommendations were offered; 1. Extension services have helped Korean farmers in achieving self-sufficiency in rice and year-round supply of green vegetables as well as upbringing rural youth, however, government changed the status of extension educators from central government staff to county/city government staff since 1997. This brought about various problems such as: decreased morale and number of extension educators, thus weakening the extension education function, weakened linkages between national and local extension offices, less opportunity for in-service education of extension educators, and weakened linkages between agricultural research and extension, etc. 2. In order to insure that extension educators are high caliber professional individuals, it is crucial to establish a system that nationally recognizes these individuals as such, and that provides a professional development path. It is important to restore the morale of extension educators to continually achieve the national goals of food production, balanced national development and preservation of environment, at the same time to meet increasing needs of farmers. 3. Because of the critical importance of diffusing innovations to agricultural producers in order to ensure quality and steady food supply, it is crucial that these issues be addressed before the extension service further deteriorates. Further research activities on agricultural extension should be conducted for more effective agricultural extension system in Korea to achieve a greater rural, national and regional development. 4. Research and implementation activities should be emphasized and encouraged to improve the cooperation and collaboration among agricultural education research and extension to better serve farmers' educational and information needs. National level research activities should be encouraged to improve the effectiveness of agricultural technology transfer including internet education programs for farmers in Korea.