• Current Research on Agriculture and Life Sciences
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• 제1권
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• pp.141-150
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• 1983

사과 Fuji와 국광을 저온(低溫) 상태하(狀態下)에서 저장방법(貯藏方法)을 달리하였을 때, 내부갈변(內部褐變) 및 PPO.의 변화(變化)에 대하여 조사한 결과는 다음과 같다. 1. P.E film저장(貯藏)에 있어서 내부갈변(內部褐變) 정도(程度)는 11월(月)에 수확(收穫)한 Fuji가 10월(月)에 수확(收穫)한 Fuji보다 많았고, 0.09mm 2%구(區)에서 가장 많이 나타났고 0.06mm 2%구(區), 0.06mm 2%구(區)의 순(順)이었으며 $CO_2$를 완전히 제거(除去)한 감압저장(減壓貯藏)에서는 내부갈변(內部褐變)을 볼 수 없었다. 2. P.E film저장중(貯藏中) Fuji의 PPO. activity 및 PPO. specific activity는 11월(月) 수확(收穫)이 10월(月) 수확(收穫)에 비해 높았으며, 0.09mm의 2%구(區)가 0.06mm구(區)보다 높았고, 저장중(貯藏中) 증가(增加)하는 경향이었고, $CO_2$를 완전히 제거(除去)한 감압저장(減壓貯藏) 동안 Fuji의 PPO. activity는 변화(變化)가 거의 없었으나 PPO. specific activity는 계속 감소(減少)하였다. 3. 국광의 PPO. activity는 Fuji에 비해 상당히 높았고 저장중(貯藏中) PPO. activity 및 specific activity는 저장(貯藏) 초기(初期)와 거의 차이(差異)가 없었다. 4. 이상(以上)으로 미루어 Fuji의 내부갈변(內附褐變)은 저온장해(低溫障害)보다는 $CO_2$장해(障害)로 보이며 품종간(品種間)의 PPO. activity의 정도(程度)와 내부갈변(內附褐變)의 관련(關聯)은 찾을 수 없는 것 같다. 그러나 Fuji의 경우 PPO. activity증대(增大)는 $CO_2$의 영향(影響)을 받은 것으로 보이며 내부갈변(內部褐變)과 어느정도 관련(關聯)이 있는 것 같다.

• Journal of Microbiology
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• 제43권3호
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• pp.244-250
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• 2005

The effect of cytochrome $c_{550}$ encoded by cccA in Bacillus subtilis during the event of sporulation was investigated. The sporulation of cccA-overexpressing mutant was significantly accelerated, while disruptant strain showed delayed sporulation in spite of the same growth rate. Activity of sporulation stage-0-specific enzyme, extracellular $\alpha-amylase$ of mutant strains was similar to that of the control strain, but cccA-overexpressing mutant exhibited higher activity of stage-II-specific alkaline phosphatase and stage-III-specific glucose dehydrogenase when compared to deletion mutant and control strain. Northern blot analysis also revealed that cccA-overexpressing mutant showed high level of spo0A transcripts, while the disruptant rarely expressed spo0A. These results suggested that although cytochrome $c_{550}$ is dispensable for growth and sporulation, expression of cccA may play an important role for initiation of sporulation through regulation of spo0A expression.

• Journal of Plant Biotechnology
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• 제47권2호
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• pp.172-178
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• 2020

Fruit-specific promoters play an important role in the improvement of traits, such as fruit quality through genetic engineering. In tomato, the development of fruit-specific promoters was previously reported, but less attention has been paid to the promoters involved in the fruit development stage. In this study, we characterized the gene expression patterns of tomato alcohol dehydrogenase 2 (SlAdh2) in various tissues of wild-type tomato (cv. Ailsa Craig). Our findings revealed that SlAdh2 expression levels were higher in the developing fruit than in the leaves, stems, and flowers. The ProSlAdh2 region, which is expressed at different stages of fruit development, was isolated from tomato genomic DNA. Following this, it was fused with a β-glucuronidase reporter gene (GUS) and introduced into wild-type tomato using Agrobacterium-mediated transformation to evaluate promoter activity in the various tissues of transgenic tomato. The ProSlAdh2:GUS promoter exhibited strong activity in the fruit and weak activity in the stems, but displayed undetectable activity in the leaves and flowers. Interestingly, the promoter was active from the appearance of the green fruit (1 cm in size) to the well-ripened stage in transgenic tomatoes, indicating its suitability for transgene expression during fruit development and ripening. Thus, our findings suggest that ProSlAdh2 may serve as a potential fruit-specific promoter for genetic-based improvement of tomato fruit quality.

• Animal cells and systems
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• 제13권3호
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• pp.289-295
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• 2009

Cyclic AMP-mediated signaling pathways regulate a number of cellular functions. In this study, we examined the regulatory role of cAMP signaling pathways in chondrogenesis of chick limb bud mesenchymal cells in vitro. Forskolin, which increases cellular cAMP levels by the activation of adenylate cyclase, enhanced chondrogenic differentiation. Inhibition of PKA with specific inhibitors (H89 or KT5720) blocked pre-cartilage condensation stage, indicating that chondrogenesis is regulated by the increase in cellular cAMP level and subsequent activation of PKA. Downstream signaling pathway of PKA leading to gene expression was investigated by examination of several nuclear transcription factors. Forskolin treatment increased transcription level for a cartilage-specific marker gene Sox9. However, inhibition of PKA with H89 led to restore expression of Sox9, indicating PKA activity was required to regulate the expression of Sox9 in chondrogenesis. In addition, CREB was highly phosphorylated at early stage of mesenchyme culture, and followed by progressive dephosphorylation. CBP and ATF, another CRE related proteins were transiently expressed at the early stage of chondrogenesis with a pattern similar to CREB phosphorylation. Electrophoretic mobility shift assays confirmed that the binding activity of CREB to the CRE is closely correlated to the phosphorylation pattern of CREB. Therefore, cAMP-mediated signal transduction to nuclear events for the induction of genes appeared to be required at the early stage of chick limb bud chondrogenesis.

• Parasites, Hosts and Diseases
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• 제61권1호
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• pp.33-41
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• 2023

The discovery of new antimalarial drugs can be developed using asynchronized Plasmodium berghei malaria parasites in vivo in mice. Studies on a particular stage are also required to assess the effectiveness and mode of action of drugs. In this report, we used endoperoxide 6-(1,2,6,7-tetraoxaspiro [7.11] nonadec-4-yl) hexan-1-ol (N-251) as a model antimalarial compound on P. chabaudi parasites. We examined the antimalarial effect of N-251 against ring-stage- and trophozoite-stage-rich P. chabaudi parasites and asynchronized P. berghei parasites using the 4-day suppressive test. The ED₅₀ values were 27, 22, and 22 mg/kg, respectively, and the antimalarial activity of N-251 was verified in both rodent malaria parasites. To assess the stage-specific effect of N-251 in vivo, we evaluated the change of parasitemia and distribution of parasite stages using ring-stage- and trophozoite-stage-rich P. chabaudi parasites with one-day drug administration for one life cycle. We discovered that the parasitemias decreased after 13 and 9 hours post-treatment in the ring-stage- and trophozoite-stage-rich groups, respectively. Additionally, in the ring-stage-rich N-251 treated group, the ring-stage parasites hindered trophozoite parasite development. For the trophozoite-stage-rich N-251 treated group, the distribution of the trophozoite stage was maintained without a change in parasitemia until 9 hours. Because of these findings, it can be concluded that N-251 suppressed the trophozoite stage but not the ring stage. We report for the first time that N-251 specifically suppresses the trophozoite stage using P. chabaudi in mice. The results show that P. chabaudi is a reliable model for the characterization of stage-specific antimalarial effects.

• Journal of Nutrition and Health
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• 제54권2호
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• pp.129-138
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• 2021

To set the estimated energy requirement (EER) in Dietary Reference Intakes for Koreans (KDRI), we need the coefficient by physical activity stage, as determined by the physical activity level(PAL). Thus, there has been demand for a tool to calculate PAL based on the physical activity diary. This study was undertaken to develop a physical activity (PA) classification table for Koreans, using the 2011 Compendium of physical activities in the United States. The PA classification table for Koreans contains 262 codes, and values of the metabolic equivalent of task (MET) for specific activities. Of these, 243 PAs which do not have Korean specific data or information, were selected from the 2011 Compendium of PAs that originated in the United States; another 19 PAs were selected from the previous research data of Koreans. The PA classification table is codified to facilitate the selection of energy values corresponding to each PA. The code for each PA consists of a single letter alphabet (activity category) and four numeric codes that display the activity type (2 digit number), activity intensity (1 digit number), and specific activities (1 digit number). In addition, the intensity (sedentary behavior, low, middle and high) of specific PA and its rate of energy expenditure in MET are presented together. The activity categories are divided into 4 areas: Daily Activity (A), Movement (B), Occupation (C), and Exercise and Sports (D). The developed PA classification table can be applied to quantify the energy cost of PA for adults in research or practice, and to assess energy expenditure and physical activity levels based on self-reported PA.

• 한국연초학회지
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• 제20권2호
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• pp.144-152
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• 1998

Changes of biological components in haemolymph of Helicoverpa assulta Guenee were investigated during the development and pupae of cold-stress periods. Protein content was the highest in the larval stage, whereas it showed somewhat lower level at the cold-stressed pupae. The level of free amino acids was high in the larval and adult stages. Althougth decresed in pupal stage, the level of free amino acid remarkably increased at the cold-stressed pupae. Total lipids were a little increased at the pupal stage, after small quantity decreased in I-day old adults, and then remarkably decreased at the cold-stressed pupae. Glycogen was increased at the pupal stage, and somewhat decreased in the stage of adult, but remarkably decreased at the cold-stressed pupae. From thin layer chromatographic analysis, glucose was detected in small quantity at 1-day old pupae, one-day old adults, and cold-stressed pupae, respectively. Each .activity of acid and alkaline phosphatases was the highest in the 1 and 7-day old pupae, respectively, and both enzyme activities were increased about two-fold compared to the activity in the cold-stressed pupae. A total of 2 phosphatase isozymes were observed in throughout the developmental stage, and a new isozyme specific to cold-stressed pupae was identified.

• Parasites, Hosts and Diseases
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• 제30권4호
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• pp.355-358
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• 1992

Oxygen radical은 생물체의 산소대사 과정의 부산물로 생성되어 세포내 여러 성분을 불환성화시키거나 미생물에 대한 방어기전으로 작용한다. 기생충에 존재하는 antioxidant enzyme은 숙주의 방어기전에서 유리하는 oxygen radical의 독성을 제거하므로 이 효소의 활성도는 기생충의 생존에 영향을 미친다고 생각하고 있다. 폐흡충은 피낭유충이 종숙주에 침입한 다음 숙주내 조직이행 시기를 거쳐서 폐에 도달하여 성충이 되므로 이 과정에서 각 시기별 산소독성과 이에 대항하는 효소의 환성이 다를 것으로 추정하였다. 폐흡충의 피낭유충과 감염후 4주, 8주, 12주에 얻은 충체의 추출물을 조효소(조효소)로 하여 SOD, catalase, peroxidase, glutathione peroxidase의 활성도를 측정하였다. 각 효소의 비환성도(specific activity) 중 catalase는 피낭유충에서 최고치였으며, SOD 와 peroxidase는 4주 충체에서 가장 높았고, glutathione peroxidase는 8주 충체에서 높았다. 이들 4가지 antioxidant효소의 비환성도는 감염 12주인 성충에서 모두 낮게 측정되어 조직 이행시기의 충체에서 더 높은 효 소 활성도를 지니고 있음을 알 수 있었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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• pp.59-63
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• 2004

By using PAGE, a study was made on the nonspecific esterase spectra of female genital organs and eggs in Bombyx mori L. The expression of 11 esterase bands was detected during ontogenesis of races and inter-races hybrids kept in Bulgaria. The gene activity of 9 esterase loci was assumed. Esterases specific for the spectrum of diapausing eggs were observed. In two esterase zones, intra- and inter-breed polymorphism was found. Based on the same breed specific expression, the existence of correspondence between esterase bands from spectra of different silkworm tissues and organs was suggested. Stage-specific expression of esterases in female genital glands, indicative of differentiated gene activity during ontogenesis, was established.

• 한국양식학회지
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• 제19권2호
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• pp.125-132
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• 2006

본 실험은 볼락 종묘를 안정적으로 대량 생산하는 데 필 수적인 자치어기의 성장과 소화효소인 trypsin, pepsin-like enzyme, amylase 그리고 lipase의 activity를 측정하여 소화생리에 대한 기초 자료를 제공하고자 수행하였다. 산출 직후 자어의 체장은 $5.01{\pm}0.22 mm$이었던 것이 산출 후 100일에는 $36.01{\pm}1.22 mm$ 까지 성장하였고, 습중량은 산출 후 70일 전후로 급격히 증가하였다. trysin 활성은 산출후 2일째 처음으로 확인되어 $7.00{\pm}1.48$ unit을 나타내고 산출후 66일 $1425{\pm}230$ unit으로 peak를 나타내었다. pepsin-like enzyme 활성은 산출 후 11일째 처음으로 확인되었고 산출후 66일째 $902{\pm}160$ unit까지 급격히 증가하였다. Lipase 활성은 산출후 2일째 $4.5{\pm}1.4$ unit으로 확인되었고 산출후 47일계에는 $38.3{\pm}0.4$unit로 peak를 나타내었다. Amylase 활성은 산출후 11일째 $0.18{\pm}0.11$ unit으로 처음 확인되었고 산출후 50일째 $23.48{\pm}5.11$ unit까지 급격히 증가하였다. specific activity는 trypsin이 산출후 14일째, pepsin-like enzyme이 61일째 peak를 나타냈다. 볼락의 체중이 현저하게 증가하는 시기에 맞춰서 각 효소와 전활성이 급격히 상승하는 것을 확인 할 수 있었다. 이것은 이시기가 위선이 기능적으로 역할을 하는 시기와 일치하므로 단백질 소화능력의 비약적인 증가가 체중 증가에 크게 관여하였음을 나타낸다. 그러므로 본 실험에서 확인 된 체중이 급격히 증가하는 시기는 볼락 양식에 있어서 사료 전환기 즉, 생물사료에서 배합사료로 전환하기에 적당하다고 할 수 있겠다.