• 생명과학회지
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• 제14권5호
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• pp.752-760
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• 2004

Nitrogenase 촉매에서 Fe-단백질을 포함하는 [4Fe-4S] 클라스터의 기능은 기질의 결합과 환원 자리를 포함하는 MoFe-단백질로 핵산 의존 전자 주개로 작용하는 것이다. 이러한 방법의 Fe-단백질의 기능은 Mofe-단백질과 상호작용을 위해 적합한 구조를 갖추며 전자 전달을 위한 추진력을 제공하기 위해 산화 환원 퍼텐셜을 변화시키는 능력에 의존한다. Nitrogenase Fe-단백질에 MgADP가 결합한 (혹은 떨어진) 구조적 정보는 핵산 결합 자리로부터 MoFe-단백질과의 결합력을 조절하기 위한 장거리 상호작용 메커니즘을 제시한다. 스위치 I과 II의 두 가지 경로가 뉴클레오티드의 신호전달 메커니즘을 담당한다. MgADP가 결합된 Fe-단백질의 구조는 Fe 단백질이 핵산과 결합할 때 관찰되는 [4Fe-4S] 클라스터의 생물리학적 특성 변화의 기초를 제공한다. 스위치, I과 II의 핵산 의존 신호전달 경로에서 특정 아미노산이 치환된 nitrogenase Fe-단백질의 구조들이 X-선 회절법에 의해서 결정되었다. 이들 경로는 아미노산 치환 연구, 구조 분석, 유사한 핵산 의존 신호전달 경로에 이용된 다른 단백질 등에 의해서도 분석되었다. 이들 경로가 거대분자 착물 형성과 분자간 전자 전달을 위한 MgADP 결합과 가수분해의 신호전달 경로로의 타당성이 조사되었다. 이러한 결과는 nitrogenase Fe 단백질과 MoFe-단백질 착물에서 Fe-단백질의 변이와 상호작용의 생물리학적 및 생화학적 특성을 위한 기초적 자료를 제공할 것이다.

• 한국식품영양학회지
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• 제10권3호
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• pp.350-359
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• 1997

백김치를 담근 후 15$^{\circ}C$에서 60일간 밀폐상태로 발효시키면서 발효일수 경과에 따른 pH, 총산함량 및 미생물수의 변화를 조사하고, 주요 미생물군집을 분리.동정하였다. 담금 즉시의 김치는 pH 6.15, 총산 0.03%였고, Gram 음성 간균류가 치우점 미생물이었으며 이들의 주요 속 구성은 Pseudomonas 55%, Enterobacter 40%, Erwinia 5%였다. 젖산균은 발효 2일 이후부터 최우점 미생물이 되었으며, 발효 4일, 12일 및 50일에 젖산균의 1차, 2차 및 3차 정상기를 각각 나타내었다. 젖산균 2차 정상기의 김치는 pH 3.51, 총산 0.59%로 적숙상태에 해당되며, 이 때 주요 젖산균의 종 구성은 Lactobacillus bavaricus 55%, Leuconostoc mesenteroides subsp. mesenteroides 42.5%, Leuconostoc paramesenteroides 2.5%였다. 젖산균 3차 정상기의 김치는 pH 3.40, 총산 1.10%로 과숙상태에 해당되며, 이 때 주요 젖산균의 종 구성은 Lactobacillus plantarum 65%, Lactobacillus brevis 35%였다. 젖산균들을 동정할 때에 Leuconostoc mesenteroides subsp. mesenteroides, Leuconostoc paramesenteroides, Lactobacillus plantarum 및 Lactobacillus brevis로 동정된 균주들은 기존의 분류체제에 비교적 잘 일치하였으나, Lactobacillus bavaricus로 동정된 균주들은 일치하지 않는 점들을 많이 나타내었다. 젖산균의 수가 증가할 때에 효모의 수가 감소하였고, 젖산균의 수가 감소할 때에 효모의 수가 증가하였다. 효모의 정상기는 젖산균이 제2정상기와 제3정상기의 사이인 30일에 나타났으며, 이 때 주요 효모의 속은 모두 Saccharomyces였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.159-159
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• 2017

Drought, a common environmental constraint, induces a range of physiological, biochemical and molecular changes in plants, and can cause severe reductions in crop yield. Consequently, understanding the molecular mechanisms of drought tolerance is an important step towards crop biotechnology. Here, we report that the rice (Oryza sativa) homeodomain-leucine zipper class IV transcription factor gene, ${\underline{R}ice}$ ${\underline{o}utermost}$ ${\underline{c}ell-specific}$ gene 10 (Roc10), enhances drought tolerance and grain yield by increasing lignin accumulation in ground tissues. Overexpression of Roc10 in rice significantly increased drought tolerance at the vegetative stages of growth and promoted both more effective photosynthesis and a reduction in water loss rate, compared with non-transgenic controls or RNAi transgenic plants. Importantly, Roc10 overexpressing plants had a higher drought tolerance at the reproductive stage of growth and a higher grain yield compared with the controls under field-drought conditions. Roc10 is mainly expressed in outer cell layers including the epidermis and the vasculature of the shoots, which coincides with areas of cell wall lignification. Roc10 overexpression elevated the expression levels of lignin biosynthetic genes in shoots, with a concomitant increase in the accumulation of lignin, while the overexpression and RNAi lines showed opposite patterns of lignin accumulation. We identified downstream target genes of Roc10 by performing RNA-seq and chromatin immunoprecipitation (ChIP)-seq analyses of shoot tissues. Roc10 was found to directly bind to the promoter of PEROXIDASEN/PEROXIDASE38, a key gene in lignin biosynthesis. Together, our findings suggest that Roc10 confers drought stress tolerance by promoting lignin biosynthesis in ground tissues.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.128-128
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• 2017

Copper (Cu) is very toxic to plant cells due to its inhibitory effects on many physiological and biochemical processes. In spite of its potential physiological and economic significance, molecular characterization after Cu stress has so far been grossly overlooked in sorghum. To explore the molecular alterations that occur in response to copper stress, the present study was executed in ten-day-old Cu-exposed leaves of sorghum seedlings. The growth of shoots was markedly reduced, and ionic alterations were prominently observed in the leaves when the seedlings were exposed to different concentrations (0, 100, and $150{\mu}M$) of $CuSO_4$. Using two-dimensional gels with silver staining, 643 differentially expressed protein spots (${\geq}1.5-fold$) were identified as either significantly increased or reduced in abundance. Of these spots, a total of 24 protein spots (${\geq}1.5-fold$) from Cu-exposed sorghum leaves were successfully analyzed by MALDI-TOF-TOF mass spectrometry. Of the 24 differentially expressed proteins from Cu-exposed sorghum leaves, a total of 13 proteins were up-regulated, and 11 proteins were down-regulated. The abundance of most identified protein species, which function in carbohydrate metabolism, stress defense, and protein translation, was significantly enhanced, while that of another protein species involved in energy metabolism, photosynthesis and growth and development were severely reduced. The resulting differences in protein expression patterns together with related morpho-physiological processes suggested that these results could help to elucidate plant adaptation to Cu stress and provide insights into the molecular mechanisms of Cu responses in $C_4$ plants. The over-expression of GAPDH plays a significant role in assisting Sorghum bicolor to attenuate the adverse effects of oxidative stress caused by Cu, and the proteins involved in resistance to stress helped the sorghum plants to tolerate high levels of Cu.

• Applied Microscopy
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• 제38권1호
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• pp.1-10
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• 2008

본 연구는 급성 수은 독성에 대한 민들레의 효과를 알아보기 위하여 시도되었다. 30 g 내외의 생쥐를 대상으로 대조군, 수은(5 mg/kg) 투여군, 수은 투여 후 민들레(3 g/kg)를 구강투여 한 후 다시 24, 48, 72, 96시간, 1주일군으로 세분하여 간장 손상 억제효과를 알아보기 위하여 생화학적 및 조직학적 실험을 실시하였다. 혈액중 aspartate amiotransferase (AST)와 alanine aminotransferase (ALT)의 수치는 민들레 투여군이 수은 투여군보다 감소되었다. 또한 간조직의 SOD와 catalase활성도 역시 민들레 투여군이 수은 투여군에 비하여 감소하였으나 통계학적 유의성은 없었다. 간 조직의 광학현미경적 관찰에서 심한 조직괴사가 관찰되지만 민들레 투여군에서는 문맥주위의 약간의 괴사와 심한 호중구 침윤현상이 관찰되었다. 전자현미경적 관찰 결과, 간장에서 수은 투여군은 간세포의 핵이 함입되어 불규칙했으며 미토콘드리아와 조면소포체의 수조가 팽대되고, 리보솜의 탈락이 관찰되었다. 민들레 투여군은 핵이 정상적인 상태로 관찰되었고, 전자밀도가 높은 미토콘드리아가 분포되어 있었으며, 리보솜이 부착된 상태로 층판구조를 형성하는 조면소포체가 관찰되었다. 이상의 연구 결과로 보아 민들레가 수은으로 유발된 간손상을 보호하는 효과가 있는 것으로 사료되며 민들레에 대한 다양한 연구가 필요할 것으로 사료된다.

• 대한한방내과학회지
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• 제41권1호
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• pp.1-13
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• 2020

Objectives: Osteoarthritis (OA) is a chronic and degenerative joint disease characterized by progressive degeneration of articular cartilage. Inflammation is a recognized and important factor of OA progression. The present study was designed to investigate the protective effect of Corni Fructus water extract (CFW) on a monosodium iodoacetate (MIA)-induced rat model of OA. Methods: Osteoarthritis was induced by injection of MIA (50 µL; 80 mg/mL) into the knee joint cavity of rats. After an adaptation period for seven days, the rats were divided into 4 groups (n=8/group): normal, control, indomethacin-treated (5 mg/kg), and CFW-treated (200 mg/kg) groups. The rats were treated orally for 14 days. Pain was evaluated by determining hind paw weight distribution. For biochemical analyses, we measured the changes in reactive oxygen species (ROS) and peroxynitrite (ONOO^-) in the knee joint. The presence of anti-oxidant proteins and inflammatory proteins was determined by western blotting. Results: The administration of CFW significantly improved the hind paw weight distribution. The ROS and ONOO^- levels of knee joint were significantly decreased in the CFW group. CFW inhibited the production of inflammatory mediators, such as COX-2, and inflammatory cytokines, including IL-6 and IL-1β, via the NF-κB signaling pathway. The expression of anti-oxidant enzymes, such as catalase and GPx-1/2 also increased significantly. Conclusions: The findings indicate that CFW has a therapeutic and protective effect on OA by suppression of inflammation. Therefore, CFW could represent a potential and effective candidate for OA treatment.

• 대한수의학회지
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• 제50권2호
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• pp.105-111
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• 2010

Carnosine is a dipeptide $(\beta-alanyl-L-histidine)$ found in mammalian brain, eye, olfactory bulb and skeletal muscle at high concentrations. Its biological functions include antioxidant and anti-glycation activities. The objectives of this study were to investigate anti-diabetic effects of carnosine as determined by blood glucose levels, glucose tolerance test (GTT), glycosylated hemoglobin, and serum biochemical and lipid levels in streptozotocin-induced diabetic mice. There were five experimental groups including normal (ICR mice), control (saline), and three groups of carnosine at doses of 6, 30, and 150 mg/kg b.w.. Carnosine was orally administered to the diabetic mice everyday for 12 weeks. There was no significant difference in body weight changes in carnosine-treated groups compared to the control. The treatments of carnosine at the dose of 6 mg/kg significantly decreased the blood glucose level compared with the control at 2 and 4 weeks. The treatments of carnosine at the doses of 6 and 30 mg/kg significantly decreased the blood glucose levels in GTT and glycosylated hemoglobin compared with the control. Carnosine significantly increased total proteins compared with the control. Carnosine at the dose of 6 mg/kg significantly decreased total cholesterol and triglyceride in the serum compared to the control. These results suggest that carnosine at a low level has a hypoglycermic effect resulting from reduction of blood glucose and that a carnosine-containing diet or drug may give a benefit for controlling diabetes mellitus in humans.

• 한국식품위생안전성학회지
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• 제11권4호
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• pp.243-259
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• 1996

This study was performed to investigate the induction of experimental atherosclerosis in rats and inhibitory effects of aloe vera on progression of atherosclerosis in rats. Adose range finding study of cholesterol and vitamin D2 for the induction of atherosclerosis and studies on the subchronic effect of aloe vera and on the chronic effect of aloe vera were carried out. A total of 3-week old 125 male rats of Sprague-Dawley were divided into 25 groups and fed with the diet containing cholesterol (0.1, 0.2, 0.3, 0.5, 1.0 and 2.0%) and vitamin D2 (500, 5000, 50000 and 500, 000 IU/100 g) for 4 weeks. 35 male rats were divided into 7 groups and fed with the diet containing aloe vera with 1.0% of cholesterol and 50, 000 IU/100 g of vitamin D2 for 4 weeks. 200 male rats were divided into 5 groups and fed with cholesterol and vitamin D2 for 6 and 12 months. Growth, clinical and pathological changes of rats in the three experiments were observed. The results were as follows: 1. In the dose-range finding study, feed intake, feed efficiency ratio and weight to body weight were increased in all of the feed groups containing 500, 000 IU/100 g of vitamin D2. Serum biochemical values of total cholesterol, high-density lipiprotein cholesterol (HDL-cholesterol), triglyceride, calcium, inorganic phosphorous and chloride of male rats in treated groups. The aorta and coronary artery of rats in all of the diet group containing 500, 000 IU/100 g of vitamin D2 showed typical atherosclerotic lesions. 2. Male rats fed with the diet containing aloe vera with 1.0% cholesterol and 50, 000 IU/100 g of vitamin D2 for 6 and 12 months did not show significant difference of diet intake and weight gain, and relative organ weight. The level of serum HDL-cholesterol and triglyceride recovered to the normal range by the aloe vera ingestation. 3. The aorta showed irregular appearence in the tunica intima with swelling, necrosis and calcification. The aorta of rat fed aloe vera diet showed no pathological lesions such as atherosclerosis of aorta. Aloe vera could have a helpful effect of vitamin D2 and cholesterol induced atherosclerosis in rats. Long-term supplementation of aloe vera may slow down the process of experimental atherosclerosis in rats have effects on the development of atherosclerosis.

• Asian-Australasian Journal of Animal Sciences
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• 제29권11호
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• pp.1585-1592
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• 2016

The present experiment was conducted to evaluate the effect of simulated heat stress on digestibility and methane ($CH_4$) emission. Four non-lactating crossbred cattle were exposed to $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$, and $40^{\circ}C$ temperature with a relative humidity of 40% to 50% in a climatic chamber from 10:00 hours to 15:00 hours every day for 27 days. The physiological responses were recorded at 15:00 hours every day. The blood samples were collected at 15:00 hours on 1st, 6th, 11th, 16th, and 21st days and serum was collected for biochemical analysis. After 21 days, fecal and feed samples were collected continuously for six days for the estimation of digestibility. In the last 48 hours gas samples were collected continuously to estimate $CH_4$ emission. Heat stress in experimental animals at $35^{\circ}C$ and $40^{\circ}C$ was evident from an alteration (p<0.05) in rectal temperature, respiratory rate, pulse rate, water intake and serum thyroxin levels. The serum lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activity and protein, urea, creatinine and triglyceride concentration changed (p<0.05), and body weight of the animals decreased (p<0.05) after temperature exposure at $40^{\circ}C$. The dry matter intake (DMI) was lower (p<0.05) at $40^{\circ}C$ exposure. The dry matter and neutral detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ compared to $25^{\circ}C$ and $30^{\circ}C$ exposure whereas, organic matter (OM) and acid detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ than $40^{\circ}C$ thermal exposure. The $CH_4$ emission/kg DMI and organic matter intake (OMI) declined (p<0.05) with increase in exposure temperature and reached its lowest levels at $40^{\circ}C$. It can be concluded from the present study that the digestibility and $CH_4$ emission were affected by intensity of heat stress. Further studies are necessary with respect to ruminal microbial changes to justify the variation in the digestibility and $CH_4$ emission during differential heat stress.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제19권1호
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• pp.109-114
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• 1997

악성고열증은 마취중 혹은 마취 후에 나타나는 마취 합병증으로 발병률은 매우 희귀하나 높은 치사율 때문에 일단 발현하면 치명적인 결과를 초래하므로 예방 및 조기 발견에 의한 조기 치료가 매우 중요하다. 예방을 위해서는 보유자의 감별이 무엇보다 중요하고 이를 위해서는 철저한 개인력 및 가족력 조사와 술전 감수성 검사가 이루어져야 한다. 의심이 되는 환자는 마취 전후에 dantrolene sodium을 투여하여야 하고 마취시 유발 마취제 및 유발 인자를 피하며 emotional stress를 피하기 위해 충분한 sedation이 요구된다. 그러나 우리 나라에는 특수 치료제인 dantrolene sodium의 확보가 어려워 조기 발견을 하고도 효과적인 치료를 하지 못하는 경우가 흔히 있으므로 dantrolene sodium을 상비약으로 비치하는 것이 좋을 것으로 사료된다. 저자들은 32세의 건강한 젊은 남자 환자가 악성형수술도중 갑작스런 체온 상승과 빈맥근강직등이 발현하여 술 후 5일만에 급성 신부전증 및 파종성혈액내응고병증(DIC)으로 사망한 악성고열증 환자를 경험하였기에 문헌고찰과 함께 보고하는 바이다.