• The Korean Journal of Physiology and Pharmacology
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• 제8권2호
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• pp.95-100
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• 2004

Ischemic preconditioning (IPC) has been accepted as a heart protection phenomenon against ischemia and reperfusion (I/R) injury. The activation of ATP-sensitive potassium $(K_{ATP})$ channels and the release of myocardial nitric oxide (NO) induced by IPC were demonstrated as the triggers or mediators of IPC. A common action mechanism of NO is a direct or indirect increase in tissue cGMP content. Furthermore, cGMP has also been shown to contribute cardiac protective effect to reduce heart I/R-induced infarction. The present investigation tested the hypothesis that $K_{ATP}$ channels attenuate DNA strand breaks and oxidative damage in an in vitro model of I/R utilizing rat ventricular myocytes. We estimated DNA strand breaks and oxidative damage by mean of single cell gel electrophoresis with endonuclease III cutting sites (comet assay). In the I/R model, the level of DNA damage increased massively. Preconditioning with a single 5-min anoxia, diazoxide $(100\;{\mu}M)$, SNAP $(300\;{\mu}M)$ and 8-(4-Chlorophenylthio)-guanosine-3',5'-cyclic monophosphate (8-pCPT-cGMP) $(100\;{\mu}M)$ followed by 15 min reoxygenation reduced DNA damage level against subsequent 30 min anoxia and 60 min reoxygenation. These protective effects were blocked by the concomitant presence of glibenclamide $(50\;{\mu}M)$, 5-hydroxydecanoate (5-HD) $(100\;{\mu}M)$ and 8-(4-Chlorophenylthio)-guanosine-3',5'-cyclic monophosphate, Rp-isomer (Rp-8-pCPT-cGMP) $(100\;{\mu}M)$. These results suggest that NO-cGMP-protein kinase G (PKG) pathway contributes to cardioprotective effect of $K_{ATP}$ channels in rat ventricular myocytes.

• 유기물자원화
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• 제13권4호
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• pp.100-106
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• 2005

사탕무즙을 이용한 알콜생산에서 배출되는 증류폐액(sugar beet stillage)을 기질로 고온성 효모인 Candida rugosa, Kl. marxianus, C. utilis를 이용해 단세포단백질을 생산 할 때 균체 생산량 및 COD 감소를 연구하였다. pH가 높아짐에 따라 균체생산량은 증가했으나 단백질 함량은 오히려 감소하였다. 조단백질생산량은 3.68g/l로 C. rugosa 가 가장 높았고 이어서 C. utilis가 2.90g/l, Kl. marxianus가 2.30g/l로 나타났다. 감소한 증류폐액기질의 COD값에 대한 조단백질생산량비율도 C. rugosa가 0.35~0.39g/l를 나타내 가장 높은 값을 보여주어 사탕무우알콜증류폐액을 기질로 이용한 단세포 단백질 생산에 있어서 종균으로서 우수성을 보여주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권7호
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• pp.991-994
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• 2000

Single cell of an indigenous phototrophic bacterium, Rhodovulum sulfidophilum, was incorporated in commercial fish feed for Oreochromis niloticus. The bacterial cell was analyzed for nutritional value and tested for toxicity and acceptability as an aquaculture feed supplement. The results showed higher survival rate and significantly higher growth rate (p<0.001) in O. niloticus fed with the bacteria incorporated fish feed. It is suggested that R sulfidophilum can be utilized as an aquaculture feed supplement.

• Journal of Microbiology and Biotechnology
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• 제29권1호
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• pp.141-150
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• 2019

The spatial landmark protein Bud8 plays a crucial role in bipolar budding in the budding yeast Saccharomyces cerevisiae. The unconventional yeast Yarrowia lipolytica can also bud in a bipolar pattern, but is evolutionarily distant from S. cerevisiae. It encodes the protein YALI0F12738p, which shares the highest amino acid sequence homology with S. cerevisiae Bud8, sharing a conserved transmembrane domain at the C-terminus. Therefore, we named it YlBud8. Deletion of YlBud8 in Y. lipolytica causes cellular separation defects, resulting in budded cells remaining linked with one another as cell chains or multiple buds from a single cell, which suggests that YlBud8 may play an important role in cell separation, which is distinct from the function of Bud8 in S. cerevisiae. We also show that the YlBud8-GFP fusion protein is located at the cell membrane and enriched in the bud cortex, which would be consistent with a role in the regulation of cell separation. The coiled-coil domain at the N-terminus of YlBud8 is important to the correct localization and function of YlBud8, as truncated proteins that do not contain the coiled-coil domain cannot rescue the defects observed in $Ylbud8{\Delta}$. This finding suggests that a new signaling pathway controlled by YlBud8 via regulation of cell separation may exist in Y. lipolytica.

• 한국자기공명학회논문지
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• 제15권1호
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• pp.25-39
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• 2011

Syndecan-4 is a transmembrane heparan sulfate proteoglycan, which is a coreceptor with integrins in cell adhesion. To get better understand the mechanism and function of Syndecan-4, it is critical to elucidate the three-dimensional structure of a single transmembrane spanning region of them. Unfortunately, it is hard to prepare the peptide because syndecan-4 is membrane-bound protein that transverse the lipid bilayer of the cell membrane. Generally, the preparation of transmembrane peptide sample is seriously difficult and time-consuming. In fact, high yield production of transmembrane peptides has been limited by experimental adversities of insufficient yields and low solubility of peptide. Here, we demonstrate experimental processes and results to optimize expression, purification, and NMR measurement condition of Syndecan-4 transmembrane peptide.

• Journal of Microbiology and Biotechnology
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• 제25권7호
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• pp.1114-1118
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• 2015

Microbial fuel cells (MFCs) have gathered attention as a novel bioenergy technology to simultaneously treat wastewater with less sludge production than the conventional activated sludge system. In two different operations of the MFC and aerobic process, microbial growth was determined by the protein assay method and their biomass yields using real wastewater were compared. The biomass yield on the anode electrode of the MFC was 0.02 g-COD-cell/gCOD-substrate and the anolyte planktonic biomass was 0.14 g-COD-cell/g-COD-substrate. An MFC without anode electrode resulted in the biomass yield of 0.07 ± 0.03 g-COD-cell/g-CODsubstrate, suggesting that oxygen diffusion from the cathode possibly supported the microbial growth. In a comparative test, the biomass yield under aerobic environment was 0.46 ± 0.07 g-COD-cell/g-COD-substrate, which was about 3 times higher than the total biomass value in the MFC operation.

• IMMUNE NETWORK
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• 제21권1호
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• pp.10.1-10.13
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• 2021

The coronavirus disease 2019 (COVID-19) pandemic (severe acute respiratory syndrome coronavirus 2) is a global infectious disease with rapid spread. Some patients have severe symptoms and clinical signs caused by an excessive inflammatory response, which increases the risk of mortality. In this study, we reanalyzed scRNA-seq data of cells from bronchoalveolar lavage fluids of patients with COVID-19 with mild and severe symptoms, focusing on Ab-producing cells. In patients with severe disease, B cells seemed to be more activated and expressed more immunoglobulin genes compared with cells from patients with mild disease, and macrophages expressed higher levels of the TNF superfamily member B-cell activating factor but not of APRIL (a proliferation-inducing ligand). In addition, macrophages from patients with severe disease had increased pro-inflammatory features and pathways associated with Fc receptor-mediated signaling, compared with patients with mild disease. CCR2-positive plasma cells accumulated in patients with severe disease, probably because of increased CCL2 expression on macrophages from patients with severe disease. Together, these results support the hypothesis that different characteristics of B cells might be associated with the severity of COVID-19 infection.

• Animal cells and systems
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• 제1권2호
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• pp.323-328
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• 1997

We have previously shown that chick muscle extracts contained at least 10 different ubiquitin C-terminal hydrolases (UCHs). In the present studies, one of the enzymes, called UCH-9, was purified by conventional chromatographic procedures using $^{125}l$-labeled ubiquitin-${\alpha}$NH-MHISPPEPESEEEEE HYC (Ub-PESTc) as a substrate. The purified enzyme behaved as a 27-kDa protein under both denaturing and nondenaturing conditions, suggesting that it consists of a single polypeptide chain. It was maximally active at pHs between 7 and 8.5, but showed little or no activity at pH below 6 and above 10. Lice other UCHs, its activity was strongly inhibited by sulfhydryl blocking reagents, such as iodoacetamide, and by Ub-aldehyde. In addition to Ub-PESTc, UCH-9 hydrolyzed Ub-aNH-protein extensions, including Ub-${\alpha}NH$-carboxyl extension protein of 80 amino acids and Ubo-${\alpha}NH$-dihydrofolate reductase. However, this enzyme was not capable of generating free Ub from mono-Ub-${\varepsilon}NH$-protein conjugates and from branched poly-Ub chains that are ligated to proteins through ${\varepsilon}NH$-isopeptide bonds. This enzyme neither could hydrolyze poly-His-tagged di-Ub. These results suggest that UCH-9 may play an important role in production of free Ub and ribosomal proteins from their conjugates.

• 한국미생물·생명공학회지
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• 제6권4호
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• pp.173-179
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• 1978

1) 고온성으로 탄화수소를 자화할 수 있는 균체를 생산하는 목적으로 90여점의 시료로부터 세 균주의 효모를 선별하여 다음의 결과를 얻었다. 2) 선정된 세 균주 효모의 최적생육온도는 4$0^{\circ}C$~45$^{\circ}C$였과. 그리고 이들은 각각 Candida tropicalis (strain A-28), Torulopsis molisichiana (strain B-8) 그리고 Candide krusei (strain C-15)로 각각 동정되었다. 3) 특히 균주 A-28은 tetradecane, hexadecane 과 octadecane을 다같이 쉽게 자화하였고 B-8과 C-15 균주는 다른 n-paraffin 보다 hexadecane을 잘 자화하였다. 4) 선정된 세 균주효모의 세대시간은 3.4.~4.0 시간, 비증식속도는 0.170~0.215이고 그리고 균체수율은 86~98%이였다. 5) 이들 균체의 조단백질은 48.2~61.5%, 지방은 3.7~8.0%, 조섬유는 3.5~4.2%, 회분은 5.6~6.7%, 무질소가용성 물질은 23.5~31.8%였고, thiamine은 0.28~0.93 mg%, riboflavin 6.03~7.3 mg%이었다. 6) 균체단백질의 아미노산조성은 비교적 골고루 함유되었다. 그러나 함황(sulfur containing) amino acid는 극히 적었다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.5467-5472
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• 2013

Objective: To construct short hairpin RNA (shRNA) eukaryotic expression vectors targeting Livin and Survivin genes, and to explore the impact of co-transfection of Livin and Survivin shRNA expression vectors on the biological behavior of HepG2 cells. Methods: shRNA eukaryotic expression vectors pSD11-Livin and pSD11-Survivin were designed and constructed then transfected into HepG2 cells separately or in combination. mRNA and protein expression in transfected cells was assessed by quantitative fluorescence PCR and Western blotting, respectively. Cell proliferation was measured by MTT assay and cell apoptosis by TUNEL assay. Results: The Livin and Survivin shRNA eukaryotic expression vectors were successfully constructed and transfected into HepG2 cells. The relative mRNA expression levels of Livin and Survivin in HepG2 cells co-transfected with pSD11-Livin and pSD11-Survivin were $0.12{\pm}0.02$ and $0.33{\pm}0.13$, respectively, which was significantly lower than levels in cells transfected with either pSD11-Livin or pSD11-Survivin (P<0.05). The relative protein expression levels of Livin and Survivin in the co-transfected cells were also significantly decreased compared to single-transfection (P<0.05). The inhibition rate of cell growth in the co-transfection group was higher than that in the single-transfection groups at 48 h, 60 h, or 72 h after transfection (P<0.01). The apoptotic rate increased to the greatest extent in the co-transfection group relative to any other group (P<0.05). Conclusions: Co-transfection with pSD11-Livin and pSD11-Survivin was more efficient than transfection with either vector alone in reducing the mRNA and protein expression of Livin and Survivin genes in HepG2 cells. Co-transfection also inhibited the proliferation of transfected cells more than the other groups, and induced cellular apoptosis more effectively.