• BMB Reports
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• v.35 no.2
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• pp.206-212
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• 2002

The NS2B-NS3(pro) polyprotein segment from the dengue virus serotype 2 strain 16681 was purified from overexpressing E. coli by metal chelate affinity chromatography and gel filtration. Enzymatic activity of the refolded NS2B-NS3(pro) protease complex was determined in vitro with dansyl-labeled peptide substrates, based upon native dengue virus type 2 cleavage sites. The 12mer substrate peptides and the cleavage products could be separated by reversed-phase HPLC, and were identified by UV and fluorescence detection. All of the peptide substrates (representing the DEN polyprotein junction sequences at the NS2A/NS2B, NS2B/NS3, NS3/NS4A and NS4B/NS5 sites) were cleaved by the recombinant protease NS2B-NS3(pro). No cleavage was observed with an enzymatically inactive S135A mutant of the NS3 protein, or with a modified substrate peptide of the NS3/NS4A polyprotein site that contained a K2093A substitution. Enzymatic activity was dependent on the salt concentration. A 50% decrease of activity was observed in the presence of 0.1M sodium chloride. Our results show that the NS3 protease activity of the refolded NS2B-NS3(pro) protein can be assayed in vitro with high specificity by using cleavage-junction derived peptide substrates.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.11
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• pp.1789-1800
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• 2019

Objective: Although alveolar macrophages play a key role in the respiratory immunity of livestock, studies on the mechanism of differentiation and survival of alveolar macrophages are lacking. Therefore, we undertook to investigate changes in the lipid metabolism and survival rate, using 3D4/31 macrophages and Dudleya brittonii which has been used as a traditional asthma treatment. Methods: 3D4/31 macrophages were used as the in vitro porcine alveolar macrophages model. The cells were activated by exposure to phorbol 12-myristate 13-acetate (PMA). Dudleya brittonii extraction was performed with distilled water. For evaluating the cell survival rate, we performed the water-soluble tetrazolium salt cell viability assay and growth curve analysis. To confirm cell death, cell cycle and intracellular reactive oxygen species (ROS) levels were measured using flow cytometric analysis by applying fluorescence dye dichlorofluorescein diacetate and propidium iodide. Furthermore, we also evaluated cellular lipid accumulation with oil red O staining, and fatty acid synthesis related genes expression levels using quantitative polymerase chain reaction (qPCR) with SYBR green dye. Glycolysis, fatty acid oxidation, and tricarboxylic acid (TCA) cycle related gene expression levels were measured using qPCR after exposure to Dudleya brittonii extract (DB) for 12 h. Results: The ROS production and cell death were induced by PMA treatment, and exposure to DB reduced the PMA induced downregulation of cell survival. The PMA and DB treatments upregulated the lipid accumulation, with corresponding increase in the acetyl-CoA carboxylase alpha, fatty acid synthase mRNA expressions. DB-PMA co-treatment reduced the glycolysis genes expression, but increased the expressions of fatty acid oxidation and TCA cycle genes. Conclusion: This study provides new insights and directions for further research relating to the immunity of porcine respiratory system, by employing a model based on alveolar macrophages and natural materials.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.2
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• pp.92-101
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• 2020

The cyclic Arg-Gly-Asp (cRGD) peptide is well-known as a binding molecule to the integrin α_vβ₃ receptor which is highly expressed on activated endothelial cells and new blood vessels in tumors. Although numerous results have been reported by the usage of cRGD peptide-based ligands for cancer diagnosis and therapy, the distinct mechanisms, and functions of cRGD-integrin binding to cancer cells are still being investigated. In this study, we evaluated the internalization efficacy of different types of cRGD peptides (monomer, dimer and tetramer form) in integrin α_vβ₃ overexpressing cancer cells. Western blot and flow cytometric analysis showed U87MG expresses highly integrin α_vβ₃, whereas CT-26 does not show integrin α_vβ₃ expression. Cytotoxicity assay indicated that all cRGD peptides (0-200 µM) had at least 70-80% of viability in U87MG cells. Fluorescence images showed cRGD dimer peptides have the highest cellular internalization compare to cRGD monomer and cRGD tetramer peptides. Additionally, transmission electron microscope results clearly visualized the endocytic internalization of integrin α_vβ₃ receptors and correlated with confocal microscopic results. These results support the rationale for the use of cRGD dimer peptides for imaging, diagnosis, or therapy of integrin α_vβ₃-rich glioblastoma.

• Parasites, Hosts and Diseases
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• v.61 no.4
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• pp.418-427
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• 2023

Toxoplasma gondii infections are primarily diagnosed by serological assays, whereas molecular and fluorescence-based techniques are garnering attention for their high sensitivity in detecting these infections. Nevertheless, each detection method has its limitations. The toxoplasmosis detection capabilities of most of the currently available methods have not been evaluated under identical experimental conditions. This study aimed to assess the diagnostic potential of enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), and immunofluorescence (IF) in BALB/c mice experimentally infected with various doses of T. gondii ME49. The detection of toxoplasmosis from sera and brain tissues was markedly enhanced in mice subjected to high infection doses (200 and 300 cysts) compared to those subjected to lower doses (10 and 50 cysts) for all the detection methods. Additionally, increased B1 gene expression levels and cyst sizes were observed in the brain tissues of the mice. Importantly, IHC, IF, and ELISA, but not RT-PCR, successfully detected T. gondii infections at the lowest infection dose (10 cysts) in the brain. These findings may prove beneficial while designing experimental methodologies for detecting T. gondii infections in mice.

• Journal of Periodontal and Implant Science
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• v.49 no.6
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• pp.366-381
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• 2019

Purpose: The purpose of this study was to evaluate the effectiveness of conventional sandblasted, large-grit, acid-etched (SLA) surface coated with a pH buffering solution based on surface wettability, blood protein adhesion, osteoblast affinity, and platelet adhesion and activation. Methods: Titanium discs and implants with conventional SLA surface (SA), SLA surface in an aqueous calcium chloride solution (CA), and SLA surface with a pH buffering agent (SOI) were prepared. The wetting velocity was measured by the number of threads wetted by blood over an interval of time. Serum albumin adsorption was tested using the bicinchoninic acid assay and by measuring fluorescence intensity. Osteoblast activity assays (osteoblast adhesion, proliferation, differentiation, mineralization, and migration) were also performed, and platelet adhesion and activation assays were conducted. Results: In both the wetting velocity test and the serum albumin adsorption assay, the SOI surface displayed a significantly higher wetting velocity than the SA surface (P=0.000 and P=0.000, respectively). In the osteoblast adhesion, proliferation, differentiation, and mineralization tests, the mean values for SOI were all higher than those for SA and CA. On the osteoblast migration, platelet adhesion, and activation tests, SOI also showed significantly higher values than SA (P=0.040, P=0.000, and P=0.000, respectively). Conclusions: SOI exhibited higher hydrophilicity and affinity for proteins, cells, and platelets than SA. Within the limits of this study, it may be concluded that coating an implant with a pH buffering agent can induce the attachment of platelets, proteins, and cells to the implant surface. Further studies should be conducted to directly compare SOI with other conventional surfaces with regard to its safety and effectiveness in clinical settings.

• Tuberculosis and Respiratory Diseases
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• v.56 no.3
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• pp.261-268
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• 2004

Background : The resurgence of tuberculosis and outbreaks of multidrug resistant (MDR) tuberculosis have increased the emphasis for the development of new susceptibility testing of the Mycobacterium tuberculosis for the effective treatment and control of the disease. Conventional drug susceptibility testings, such as those using egg-based or agar-based media have some limits, such as the time required and difficulties in determining critical inhibitory concentrations, but these are still being used in many diagnostic laboratories because of no better lternatives, considering cost and accuracy. To overcome these limits, a rapid and simple method for new susceptibility testing, using live and dead assays, was applied for a bacterial cell viability assay to distinguish dead from live bacterial cells based on two-color fluorescence. Materials and Methods Strains : Forty strains were used in this study, 20 susceptible to all antituberculosis drugs and the other 20 resistant to the four first line antituberculosis drugs isoniazid, rifampicin, streptomycin and ethambutol. Antibiotics : The four antibiotics were dissolved in 7H9 broth to make the following solutions: $0.1{\mu}g\;isoniazid(INH)/m{\ell}$, $0.4{\mu}g\;rifampicin(RMP)/m{\ell}$, $4.0{\mu}g\;streptomycin(SM)/m{\ell}$ and $4.0{\mu}g\;ethambutol(EMB)/m{\ell}$. Results : Live and dead Mycobacterium tuberculosis cells fluoresced green and red with the acridin (Syto 9) and propidium treatments, respectively. These results are very well accorded with conventional drug susceptibility testing by proportional method on Lowensen-Jensen media (L-J) containing 4 drugs (INH, RMP, EMB and SM), showing a 93.7 % accordance rate in susceptible strains and 95% in resistant strains. Conclusion : The results of the drug susceptibility testing using the live and dead bacterial cell assay showed high accordance rates compared with the conventional proportion method on L-J. This finding suggests that the live and dead bacterial cell assay can be used as an alternative to conventional drug susceptibility testing for M. tuberculosis strains.

• Korean Journal of Acupuncture
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• v.27 no.2
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• pp.95-105
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• 2010

Objectives : The purpose of this study is to investigate the effect of Bacillus-fermented Scutellariae Radix acupuncture solution (SB) on interleukin(IL) production in mouse macrophage stimulatedby lipopolysaccaride(LPS). Methods : Productions of interleukins were measured y High-throughput Multiplex Bead based Assay with Bio-plex Suspension Array System based on $xMAP^{(R)}$(multi-analyte profiling beads) technology. To begin with, cell culture supernatant was obtained after treatment with LPS(1 ${\mu}g/mL$) and SB for 24 hour. Then, it was incubated with the antibody-conj${\mu}g$ated beads for 30 minutes. And detection antibody was added and incubated for 30 minutes. After incubating for 30 minutes, Strepavidin-conjugated Phycoerythrin(SAPE) was then added. Incubating for another 30 minutes, the level of SAPE fluorescence was analyzed on Bio-plex Suspension Array System. Results : The results of the experiment are as follows. SB significantly inhibited the LPS-induced production of IL-3($9.15{\pm}0.35$ pg/mL) by $6.92{\pm}0.05,\;7.21{\pm}0.11,\;6.96{\pm}0.33,\;and\;7.45{\pm}0.74$ pg/mL at the concentration of 25, 50, 100, and 200 ${\mu}g/mL$ in mouse macrophage RAW 264.7 cells (p<0.05). SB significantly inhibited the LPS-induced production of IL-5($7.30{\pm}0.48$ pg/mL) by $6.50{\pm}0.29,\;6.30{\pm}0.25,\;6.30{\pm}0.25,\;and\;5.80{\pm}0.25$ pg/mL at the concentration of 25, 50 100, and 200 ${\mg}g/mL$ in RAW 264.7 cells (p<0.05). SB significantly inhibited the LPS-induced productiion of IL-9($17.26{\pm}0.19$ pg/mL) by $15.01{\pm}0.43$ pg/mL at the concentration of 25 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). SB significantly inhibited the LPS-induced productioh of IL-13($187.80{\pm}2.90$ pg/mL) by $152.80{\pm}4.25,\;172.80{\pm}3.97,\;162.10{\pm}6.67,\;and\;165.30{\pm}11.80$ pg/mL at the concentration fo 25, 50, 100, and 200 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). SB significantly inhibited the LPS-induced production of IL-17($18.30{\pm}0.95$ pg/mL) by $13.30{\pm}1.25,\;13.80{\pm}1.11,\;13.30{\pm}0.75,\;and\;14.00{\pm}1.08$ pg/mL at the concentration of 25, 50 100, and 200 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). SB significantly inhibited the LPS-induced production of IL-23($43.90{\pm}0.83$ pg/mL by $39.50{\pm}1.26,\;38.00{\pm}1.78,\;and\;39.60{\pm}2.49$ pg/mL at the concentration of 25, 100, and 200 ${\mu}g/mL$ in RAW 264.7 cells(p<0.05). Conclusions : These results suggest that SB has anti-inflammatory activity related with its inhibition of IL-3, IL-5, IL-13, IL-17, and IL-23 production in macrophages.

• Journal of Ginseng Research
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• v.48 no.4
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• pp.395-404
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• 2024

Background: Ginsenoside Rg₁ (Rg₁) is one of the main active components in Chinese medicines, Panax ginseng and Panax notoginseng. Research has shown that Rg₁ has a protective effect on the cardiovascular system, including anti-myocardial ischemia-reperfusion injury, anti-apoptosis, and promotion of myocardial angiogenesis, suggesting it a potential cardiovascular agent. However, the protective mechanism involved is still not fully understood. Methods: Based on network pharmacology, ligand-based protein docking, proteomics, Western blot, protein recombination and spectroscopic analysis (UV-Vis and fluorescence spectra) techniques, potential targets and pathways for Rg₁ against myocardial ischemia (MI) were screened and explored. Results: An important target set containing 19 proteins was constructed. Two target proteins with more favorable binding activity for Rg₁ against MI were further identified by molecular docking, including mitogen-activated protein kinase 1 (MAPK1) and adenosine kinase (ADK). Meanwhile, Rg₁ intervention on H9c2 cells injured by H₂O₂ showed an inhibitory oxidative phosphorylation (OXPHOS) pathway. The inhibition of Rg₁ on MAPK1 and OXPHOS pathway was confirmed by Western blot assay. By protein recombination and spectroscopic analysis, the binding reaction between ADK and Rg₁ was also evaluated. Conclusion: Rg₁ can effectively alleviate cardiomyocytes oxidative stress injury via targeting MAPK1 and ADK, and inhibiting oxidative phosphorylation (OXPHOS) pathway. The present study provides scientific basis for the clinical application of the natural active ingredient, Rg₁, and also gives rise to a methodological reference to the searching of action targets and pathways of other natural active ingredients.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1782-1789
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• 2012

We have developed a novel type of polymer nanogel loaded with anticancer drug based on bio-derived poly(${\gamma}$-glutamic acid) (${\gamma}$-PGA). ${\gamma}$-PGA is a highly anionic polymer that is synthesized naturally by microbial species, most prominently in various bacilli, and has been shown to have excellent biocompatibility. Thiolated ${\gamma}$-PGA was synthesized by covalent coupling between the carboxyl groups of ${\gamma}$-PGA and the primary amine group of cysteamine. Doxorubicin (Dox)-loaded ${\gamma}$-PGA nanogels were fabricated using the following steps: (1) an ionic nanocomplex was formed between thiolated ${\gamma}$-PGA as the negative charge component, and Dox as the positive charge component; (2) addition of poly(ethylene glycol) (PEG) induced hydrogen-bond interactions between thiol groups of thiolated ${\gamma}$-PGA and hydroxyl groups of PEG, resulting in the nanocomplex; and (3) disulfide crosslinked ${\gamma}$-PGA nanogels were fabricated by ultrasonication. The average size and surface charge of Dox-loaded disulfide cross-linked ${\gamma}$-PGA nanogels in aqueous solution were $136.3{\pm}37.6$ nm and $-32.5{\pm}5.3$ mV, respectively. The loading amount of Dox was approximately 38.7 ${\mu}g$ per mg of ${\gamma}$-PGA nanogel. The Dox-loaded disulfide cross-linked ${\gamma}$-PGA nanogels showed controlled drug release behavior in the presence of reducing agents, glutathione (GSH) (1-10 mM). Through fluorescence microscopy and FACS, the cellular uptake of ${\gamma}$-PGA nanogels into breast cancer cells (MCF-7) was analyzed. The cytotoxic effect was evaluated using the MTT assay and was determined to be dependent on both the concentration and treatment time of ${\gamma}$-PGA nanogels. The bio-derived ${\gamma}$-PGA nanogels are expected to be a well-designed delivery carrier for controlled drug delivery applications.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.557-566
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• 2022

The Japanese eel Anguilla japonica is a highly valued research object that is important for aquaculture in Asia, including the Republic of Korea. However, few studies have been conducted analyzing parentage using microsatellite markers derived from the Japanese eel. We acquired Japanese eel genome data using next generation sequencing technology, and constructed a draft genome comprising 1,087 Mbp. Using the Simple Sequence Repeat Identification Tool program, 444,724 microsatellites were identified. Of these, 1,842 microsatellites located in the 3' untranslated region, which are stably inherited, were finally selected. Ninety-six primers were selected to validate polymorphism at these microsatellites, and 9 primers were finally identified for multiplex analysis. Using multiplex polymerase chain reaction with three different fluorescence chemistries, we performed parentage analysis of an artificial Japanese eel population. CERVUS software was used to calculate the logarithm of the odds (LOD) scores and the confidence of the parentage assignments. The results presented here show that 83 out of 85 paternity cases were assigned at 95% confidence to a candidate father and mother with LOD scores ranging from 4.79 to 28.2. This study provided a microsatellite marker-based assay for parentage analysis of Japanese eels, which will be useful for selective breeding and genetic diversity studies.