• 한국해양학회지:바다
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• 제23권1호
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• pp.20-31
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• 2018

포식 기생생물 Amoebophrya spp.는 적조를 유발하는 다양한 와편모류 종들을 감염시켜 적조를 제어하는 생물학적 요인으로 잘 알려져 있다. 본 연구는 전 세계 연안에서 유해 적조를 유발하는 와편모류 Akashiwo sanguinea를 감염시키는 포식성 기생생물 Amoebophrya sp.의 감염력에 대해 물리적 환경요인으로서 수온이 미치는 영향에 대해 살펴보았다. 연구 결과, 적조생물 A. sanguinea에 대한 Amoebophrya의 감염력과 세대시간은 수온의 변화에 따라 크게 영향을 받는 것으로 나타났으며, 수온이 낮을수록 숙주 세포내 발달이 급격하게 느려져서 기생생물의 총 세대시간이 $25^{\circ}C$에서는 약 $58{\pm}0.1h$과 $20^{\circ}C$에서는 $83{\pm}0.1h$, $15^{\circ}C$에서는 $115{\pm}0.1h$의 범위를 나타내어 각 온도 조건에서 유의한 차이를 보였으며(p<0.001), 온도가 낮을수록 포식성 기생생물의 총 세대시간이 크게 길어지는 것으로 나타났다. 또한 감염율은 $25^{\circ}C$에서 $71.5{\pm}0.30%$의 범위로 가장 높게 나타났고, $20^{\circ}C$와 $15^{\circ}C$에서는 각각 $54.3{\pm}1.68%$와 $29.6{\pm}1.42%$의 범위를 나타내어 온도가 낮아질수록 감염율이 크게 감소하는 것으로 나타났다. 이러한 연구결과는 저수온기에 발생한 A. sanguinea의 적조에는 포식 기생생물의 감염으로 인한 생물학적 제어 효과가 크게 감소하는 것으로 판단된다. 뿐만 아니라, 숙주개체군의 거동과 관련하여 포식 기생생물의 감염력에 영향을 주는 요인으로서 수온이 하나의 주요 변수로서 작용할 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제27권12호
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• pp.2119-2128
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• 2017

Citrinin (CIT) is a toxic secondary metabolite produced by fungi belonging to the Penicillium, Aspergillus, and Monascus spp. This toxin has been detected in many agricultural products. In this study, a strain Y3 with the ability to eliminate CIT was screened and identified as Cryptococcus podzolicus, based on the sequence analysis of the internal transcribed spacer region. Neither uptake of CIT by cells nor adsorption by cell wall was involved in CIT elimination by Cryptococcus podzolicus Y3. The extracellular metabolites of Cryptococcus podzolicus Y3 stimulated by CIT or not showed no degradation for CIT. It indicated that CIT elimination was attributed to the degradation of intracellular enzyme(s). The degradation of CIT by C. podzolicus Y3 was dependent on the type of media, yeast concentration, temperature, pH, and initial concentration of CIT. Most of the CIT was degraded by C. podzolicus Y3 in NYDB medium at 42 h but not in PDB medium. The degradation rate of CIT was the highest (94%) when the concentration of C. podzolicus Y3 was $1{\times}10^8cells/ml$. The quantity of CIT degradation was highest at $28^{\circ}C$, and there was no degradation observed at 3$5^{\circ}C$. The study also showed that acidic condition (pH 4.0) was the most favorable for CIT degradation by C. podzolicus Y3. The degradation rate of CIT increased to 98% as the concentration of CIT was increased to $20{\mu}g/ml$. The toxicity of CIT degradation product(s) toward HEK293 was much lower than that of CIT.

• 한국식품저장유통학회지
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• 제18권1호
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• pp.65-71
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• 2011

본 연구에서는 도라지 분말을 유기용매로 추출한 후 도라지의 추출물과 분획물들에 의한 세포 내 활성산소종 및 glutathione (GSH)를 측정하여 항산화효과를 검토하였고 NO 생성 저해 효과를 알아보았다. 세포 내 활성산소종 생성억제 실험에서 건조 도라지의 A+M 및 MeOH 추출물과 추출물을 n-hexane, 85% aq. MeOH, n-BuOH, water로 다시 추출하여 얻어진 각각의 분획물들을 농도별로 HT1080 세포에 처리하였을 때 A+M과 MeOH 추출물 모두 측정시간 120분 동안 $500\;{\mu}M$ $H_2O_2$만을 처리한 control군에 비해 세포 내 활성산소종을 크게 억제시켰으며, MeOH 추출물에 의한 항산화 효과가 더 높게 나타났다. 또한, 각 분획물들 중 n-BuOH 분획물이 다른 분획물들에 비해 우수한 항산화 활성을 보였다. GSH 농도 측정 실험에서 A+M 및 85% aq. MeOH 분획물를 처리했을 때 GSH 함량이 증가하였다. NO 생성 저해 실험에서는 A+M 및 MeOH 추출물이 0.01 및 0.05 mg/mL의 농도에서 NO 생성을 억제하는 것으로 나타났으며, A+M 추출물에 의한 저해 효과가 높았다. 각 분획물들은 모두 control보다 낮은 NO 생성량을 나타내었으며, 특히 85% aq. MeOH 및 n-BuOH 분획물은 0.05 mg/mL 농도에서 blank에 가까운 NO 생성 억제율을 나타냈다. 이상의 연구결과로부터 n-BuOH 분획물에 의한 세포 내 활성산소종 생성 억제 효과 및 NO 생성 저해 효과가 우수함을 알 수 있었으며, 향후 분획물의 분리 정제를 통한 새로운 기능성 물질의 개발이 필요할 것으로 사료된다.

• Biomolecules & Therapeutics
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• 제17권1호
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• pp.92-97
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• 2009

As nanomaterials might enter into cells and have high reactivity with intracellular structures, it is necessary to assay possible genotoxic risk of them. One of these approaches, we investigated possible genotoxic potential of gold nanoparticle (AuNP) using L5178Y cells. Four different sizes of AuNP (4, 15, 100 or 200 nm) were synthesized and the sizes and structures of AuNP were analyzed using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and stability was analyzed by a UV/Vis. Spectrophotometer. Cytotoxicity was assessed by direct cell counting, and cellular location was detected by dark field microscope at 6, 24 and 48 h after treatment of AuNP. Comet assay was conducted to examine DNA damage and tumor necrosis factor (TNF)-${\alpha}$ mRNA level was assay by real-time reverse transcription polymerase chain reaction. Synthetic AuNP (4, 50, 100 and 200 nm size) had constant characteristics and stability confirmed by TEM, SEM and spectrophotometer for 10 days, respectively. Dark field microscope revealed the location of AuNP in the cytoplasm at 6, 24 and 48 h. Treatment of 4 nm AuNP induced dose and time dependent cytotoxicity, while other sizes of AuNP did not. However, Comet assay represented that treatment of 100 nm and 200 nm AuNP significantly increased DNA damage compared to vehicle control (p <0.01). Treatment of 100 nm and 200 nm AuNP significantly increased TNF-${\alpha}$ mRNA expression compared to vehicle control (p<0.05, p<0.01, respectively). Taken together, AuNP induced DNA damage in L5178Y cell, associated with induction of oxidative stress.

• The Korean Journal of Physiology and Pharmacology
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• 제26권5호
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• pp.335-345
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• 2022

Pyroptosis is an inflammatory form of programmed cell death that is linked with invading intracellular pathogens. Cardiac pyroptosis has a significant role in coronary microembolization (CME), thus causing myocardial injury. Tanshinone IIA (Tan IIA) has powerful cardioprotective effects. Hence, this study aimed to identify the effect of Tan IIA on CME and its underlying mechanism. Forty Sprague-Dawley (SD) rats were randomly grouped into sham, CME, CME + low-dose Tan IIA, and CME + high-dose Tan IIA groups. Except for the sham group, polyethylene microspheres (42 ㎛) were injected to establish the CME model. The Tan-L and Tan-H groups received intraperitoneal Tan IIA for 7 days before CME. After CME, cardiac function, myocardial histopathology, and serum myocardial injury markers were assessed. The expression of pyroptosis-associated molecules and TLR4/MyD88/NF-κB/NLRP3 cascade was evaluated by qRT-PCR, Western blotting, ELISA, and IHC. Relative to the sham group, CME group's cardiac functions were significantly reduced, with a high level of serum myocardial injury markers, and microinfarct area. Also, the levels of caspase-1 p20, GSDMD-N, IL-18, IL-1β, TLR4, MyD88, p-NF-κB p65, NLRP3, and ASC expression were increased. Relative to the CME group, the Tan-H and Tan-L groups had considerably improved cardiac functions, with a considerably low level of serum myocardial injury markers and microinfarct area. Tan IIA can reduce the levels of pyroptosis-associated mRNA and protein, which may be caused by inhibiting TLR4/MyD88/NF-κB/NLRP3 cascade. In conclusion, Tanshinone IIA can suppress cardiomyocyte pyroptosis probably through modulating the TLR4/MyD88/NF-κB/NLRP3 cascade, lowering cardiac dysfunction, and myocardial damage.

• Tuberculosis and Respiratory Diseases
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• 제44권3호
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• pp.583-591
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• 1997

연구배경 : 만성폐질환 환자들의 운동 능력 감소의 한 기전으로 제시되고 있는 골격근의 기능 저하는 질환의 병태생리에 기인하는 만성적인 저산소증으로 야기되는 산소성 인산화과정의 장애로 인한 근육 대사과정의 변화가 주요 원인으로 알려져 있다. 그러나 저산소증은 없으나 운동시 호흡곤란을 호소하며 운동능력의 감소를 나타내는 만성폐질환 환자들에서도 이러한 근육 대사 과정의 변화가 나타나는지에 대해서는 연구된 바 없다. 이에 저자들은 $^{31}P$ MRS를 이용하여 이들에서 전박 골격근의 대사 변화를 비슷한 연령의 정상인의 대사와 비교 관찰하므로써, 이들에서도 운동 능력 감소의 한기전으로서 역시 골격근의 대사 변화가 관여할 가능성을 알아보고자 하였다. 연구방법 : 6 명의 만성폐쇄성폐질환 남자 환자 및 1명의 폐유육종증 남자 환자와 5명의 비슷한 연령의 건강한 성인 남자들의 전박근을 대상으로 $^{31}P$ MRS 검사를 실시하였다. 환자군의 평균 연령은 $56.7{\pm}12.1$세였으며 대조군의 평균 연령은 $51.6{\pm}13.6$세였다. 각 대상인의 전박 골격근을 대상으로 $^{31}P$ MRS검사를 안정시, 운동시 및 20분간의 회복시에 걸쳐 시행하였으며, 검사 중 계산된 세포내 산소성인산화 능력을 반영하는 Pi/PCr(inorganic phosphate/phosphocreatine)의 비와 세포내 pH(pHi)의 변화를 양군간에 비교하였다. 결 과 : 안정시 골격근 세포내 pHi는 양군간에 차이가 없었으나, 운동시작 2분후 pHi는 환자군이 $6.82{\pm}0.1$, 대조군이 $6.97{\pm}0.05$로 환자군에서 유의하게 낮았다. 그러나 극심한 피로상태에서 pHi는 환자군이 $6.70{\pm}0.10$, 대조군이 $6.78{\pm}0.09$로 환자군이 낮은 경향을 보였으나 통계적으로 유의한 차이는 없었다. 근육세포 내 산소성인산화 능력이 지표인 Pi/PCr은 안정시, 운동중 및 극심한 피로상태에서 모두 양군간에 통계적으로 유의한 차이는 없었다. 회복시 초기 4분간에 걸쳐 관찰한 Pi/PCr의 회복 및 pHi가 안정시 50%수준으로 회복되는데는 시간은 양군간에 차이가 없었으며, 운동지속 시간도 유의한 차이는 없었다.

• The Korean Journal of Physiology
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• 제24권1호
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• pp.123-129
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• 1990

A comparative study of acid-base balance has been made between acidemia-induced hyperkalemia and hyperkalemia-induced acidemia. A group of rabbits was infused 0.1 N hydrochloric acid solution and metabolic acidosis was induced. Another group was administered 20 mM potassium chloride solution and hyperkalemia was induced. The third group was infused 0.1 N hydrochloric acid and 20 mM potassium chloride solution, simultaneously. Acid-base data and plasma potassium ion concentration were monitored every thirty minutes in these three groups of rabbits. Following results were obtained: 1 ) Along with the infusion of hydrochloric acid, acute metabolic acidosis was induced in the rabbits. Plasma bicarbonate ion concentration decreased primarily in this group. As a respiratory compensation, there was a tendency of reduction of arterial $Pco_{2}$. The alteration of data became larger along with the amount of administration and the time elapsed. However, hyperkalemia was not so severe compared with the second group. 2) In potassium chloride infused group, plasma potassium ion concentration increased along with the time elapsed and the amount of infusion. And the alteration of acid-base data was parrallel to the level of potassium ion concentration, above all depression of pH was prominent. 3) Above data suggest that when acute metabolic acidosis was induced, exchange of intracellular potassium ion with extracellular hydrogen ion seems significant for the regulation of extracellular acid-base balance. And when hyperkalemia was induced with the infusion of potassium chloride solution, the exchange of intracellular hydrogen ion with extracellular potassium ion also seems significant for the regulation of extracellular potassium balance. 4) In the group of rabbits infused hydrochloric acid and potassium simultaneously, disturbances of acid-base balance and potassium balance were much more severe than two other groups. In these mixed disturbances, the process of compensatory mechanism might be inhibited and one disturbance might aggregate each other. 5) Through above data it has been postulated that in acid-base disturbance potassium balance can be sacrificed as a compensatory mechanism, and vice versa in disturbance of potassium balance. And our data also suggest that hydrogen ion and potassium ion are compensatory pair, one another.

• Journal of Microbiology and Biotechnology
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• 제29권2호
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• pp.330-338
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• 2019

Chronic infection with intracellular Brucella abortus (B. abortus) in livestock remains as a major problem worldwide. Thus, the search for an ideal vaccine is still ongoing. In this study, we evaluated the protective efficacy of a combination of B. abortus recombinant proteins; superoxide dismutase (rSodC), riboflavin synthase subunit beta (rRibH), nucleoside diphosphate kinase (rNdk), 50S ribosomal protein (rL7/L12) and malate dehydrogenase (rMDH), cloned and expressed into a pMal vector system and $DH5{\alpha}$, respectively, and further purified and applied intraperitoneally into BALB/c mice. After first immunization and two boosters, mice were infected intraperitoneally (IP) with $5{\times}10^4CFU$ of virulent B. abortus 544. Spleens were harvested and bacterial loads were evaluated at two weeks post-infection. Results revealed that this combination showed significant reduction in bacterial colonization in the spleen with a log protection unit of 1.31, which is comparable to the average protection conferred by the widely used live attenuated vaccine RB51. Cytokine analysis exhibited enhancement of cell-mediated immune response as IFN-${\gamma}$ is significantly elevated while IL-10, which is considered beneficial to the pathogen's survival, was reduced compared to control group. Furthermore, both titers of IgG1 and IgG2a were significantly elevated at three and four-week time points from first immunization. In summary, our in vivo data revealed that vaccination with a combination of five different proteins conferred a heightened host response to Brucella infection through cell-mediated immunity which is desirable in the control of intracellular pathogens. Thus, this combination might be considered for further improvement as a potential candidate vaccine against Brucella infection.

• 생명과학회지
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• 제15권2호
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• pp.253-260
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• 2005

인체 MCAK 단백질을 Escherichia. coli에서 재조합 단백질로 발현하였다. 이를 SDS-PAGE 후 electroelution으로 정제하고 항원으로 사용하여 rat에서 다클론성 항체생성을 유도한 결과, 생성된 항체는 Western blot analysis에 의해 인체 MCAK 단백질 (81 kDa)을 특이적으로 인식할 수 있었으며, Jurkat T cells과 293T cells에 있어서 MCAK 단백질의 대부분이 핵 내에 위치함을 확인할 수 있었다. 세포주기에 따른 MCAK 단백질의 발현양의 변화를 조사하기 위해, Jurkat T cells을 Hydroxy urea 또는 Nocodazole의 처리로 $G_{1}/S$ boundary 그리고 $G_{2}/M$ boundary에 blocking하고 이로부터 release 시키는 시간을 달리하여 다양한 세포주기상에 위치한 Jurkat T cells을 확보하였다. 각각의 Jurkat T cells로부터 cell lysate를 얻어서 Western blot analysis를 시도한 결과, MCAK 발현양은 S phase에서 가장 높았으며 MCAK의 SDS-PAGE상의 mobility가 81 kDa에서 84 kDa로 shift됨을 확인하였다. MCAK의 전기영동상의 mobility shift에 의한 slow moving $p84^{HsMCAK}$는 S phase 후반부터 나타나기 시작하며 $G_{2}/M$ phase에 최대였고 $G_{1}$, phase에서는 확인되지 않았다. 이는 세포주기에 따라 MCAK의 단백질의 인산화 양상이 달라짐을 시사한다. 생성된 항체를 이용한 Immunocytochemical analysis의 결과, 인체 MCAK 단백질은 세포주기의 interphase에서는 주로 중심체와 핵에 존재하며, M phase의 각 단계에 따라서 spindle pole, centromere, spindle fiber 또는 midbody에 존재함을 확인하였다. 이러한 연구 결과는 E. coli에서 발현된 재조합 HsMCAK 단백질을 항원으로 하여 rat에서 생산한 다클론성 항체가 HsMCAK 단백질을 특이적으로 인식할 수 있음과 또한 HsMCAK 단백질의 인산화를 나타내는 SDS-PAGE상의 mobility-shift가 $G_{2}/M$ phase에 최대에 도달하는 양상으로 세포주기에 따라 변동됨을 나타내며, HsMCAK의 인산화와 HsMCAK의 세포 내 위치간의 관련성을 시사한다. 아울러 이러한 연구결과는 hamster 및 Xenopus 등에서 주로 연구되고 있는 MCAK의 세포주기상의 주요기능이 인체세포에도 적용될 수 있음을 시사한다.

• Applied Microscopy
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• 제20권1호
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• pp.36-50
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• 1990

This experiment was performed to study the morphological responses of the enterochromaffin cells in the duodenal mucosa of rabbit following bile duct ligation. Adult male rabbits were divided into normal, sham operation and experimental groups. Bile duct ligation was performed under ether anesthesia and animals were sacrificed on the 1st, 3rd, 5th, 7th and 14th day after operation. Mucosal specimens from the duodenum were prefixed with 2.5% glutaraldehyde-1.5% paraformaldehyde(0.1M Millonig's phosphate buffer, pH 7.3), followed by postfixation with 1% osmium tetroxide(0.1M Millonig's phosphate buffer, pH 7.3), and embedded within araldite mixture. The sections were cut on a LKB-V ultratome, and observed under a JEM 100CX II electron miroscope. The results were as follow; 1. Irregularities of the nuclei of the enterochromaffin cells were noticed from the 1st day after bile duct ligation, and concentration of the chromatin in the nucleus was more frequently observed on the 7th and the 14th day. 2. The granular endoplasmic reticulum and Golgi complex of the enterochromaffin cell were more developed than those of the normal on the 1st day after bile duct ligation, but they showed poor organization from the 3rd day. 3. Amount of the microfilaments in the enterochromaffin cell was significantly increased from the 5th day after bile duct ligation and they were more frequently observed in the vicinity of the nucleus. 4. Vacuoles with various electron densities in the enterochromaffin cell were increased in number from the 3rd day after bile duct ligation. 5. Glycogen-like particles in the enterochromaffin cell were frequently observed on the 3rd and the 5th day after bile duct ligation. 6. In the early stage of the ligation of bile duct, in the enterochromaffin cells, well developed intracellular organelles, such as granular endoplasmic reticulum and Golgi apparatus were pronounced. But, in the later stage, the cells contained poor organelles, with the some structural sign of necrotic change.