• Biomedical Science Letters
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• v.26 no.4
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• pp.336-343
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• 2020

The present study was carried out to investigate the possibility that bispidinone derivative makes anticancer drug availability to human cervical carcinoma cell. The B8 has the lowest IC50 value among B8, B9 and B10 which are bispidinone analogue with bromide. According to cytotoxic test through WST-8 assay, B8 shows the most magnificent cytotoxicity effectiveness with 76 μM of IC50 value. In human cervical carcinoma cell treated with B8, it noticeably controlled cellular multiplication by increase of concentration and time. Furthermore, morphological changes like cellular shrink, disruption and nuclear condensation, feature of apoptosis, are observed. Annexin V-FITC/PI double staining assay test proved that B8 can cause apoptosis. Moreover, after treatment with 76 μM of B8, flow cytometry analysis shows that increase of active oxygen species are induced and membrane potential in mitochondria is decreased. Manifestation of Bcl-2 family and caspase cascades protein provides evidence that B8 induces apoptosis through mitochondria and caspase-related pathway. Taken together, we suggested that B8 reduced membrane potential in mitochondria and induce apoptosis through the pathway depended on mitochondria and caspase.

• Membrane Journal
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• v.33 no.1
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• pp.46-51
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• 2023

The purpose of this study is to analyze the utilization forms of hydrogen fuel cells, which are the core of building a smart city, and suggest ways to solve them. In the case of power plants to utilize hydrogen fuel cell, it was analyzed as the most promising form of use in the future due to the advantage of being free from intermittence problems. However, despite many advantages, local residents' opposition continues to emerge due to concerns about explosions and the problem of carbon dioxide generation in the case of certain hydrogen production methods, and it is analyzed that resolving them will be the main key to establishing the smart city. Finally, by analyzing the current hydrogen production method and identifying the problems facing it, the solution for the complete construction of the smart city was presented.

• Elastomers and Composites
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• v.58 no.3
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• pp.112-120
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• 2023

Herein, we propose a facile water-processible method to develop an eggshell membrane (ESM)-embedded waterborne polyurethane (WPU)-based bio-degradable and bio-compatible coating material that exhibits attractive tactile properties. Virgin ESM is not dispersible in water. Hence, to develop the ESM-based WPU composite, soluble ESM (S-ESM) was first extracted by de-crosslinking the ESM. The extracted S-ESM at different concentrations (0, 0.5, 1.0, 1.5 wt %) was mixed with WPU. Compared to virgin WPU, the viscosity of S-ESM/WPU dispersion and the in-plane coefficient of friction (COF) of the composite film surfaces decreased with an increase in the S-ESM content. In addition, an increase in the S-ESM content improved the tribo-positive characteristics of the film. Different good touch-feeling biomaterials, such as fur, feather, and human skin exhibit tribo-positivity. Thus, the enhanced tribo-positive characteristics of the S-ESM/WPU and the decrease in their COF owing to an increase in the S-ESM content imply the enhancement of its touch-feeling performance. The S-ESM embedded WPU composites have potential applications as coating materials in various fields, including automobile interiors and artificial leather.

• Journal of the Korean Chemical Society
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• v.59 no.1
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• pp.22-30
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• 2015

The effect of diphtheria toxin on cell membrane lipids was studied by examining the phospholipase D (PLD) activity and free fatty acids (FFA) release in HepG2 cells. The diphtheria toxin effects on lipid alteration show apparently maximal at pH 5.1, stimulating PLD activity nearly 3.5 fold and enhancing FFA release approximately 5 fold over the control. These results indicate that the membrane is perturbed and its lipid component is rearranged during the diphtheria toxin translocation. Digitonin, a random membrane perturbing detergent, exhibit about four-fold higher perturbation effect over the diphtheria toxin at neutral pH. This observation suggests that the membrane perturbation induced by diphtheria toxin appears to be rather selective. To investigate the cause of the membrane perturbation, Cibacron blue, an inhibitor of membrane pore formation, and hemagglutinin, an influenza virus with fusion peptide, were tested for their effects on diphtheria toxin action. Cibacron blue decreased the diphtheria toxin effect by almost 50%, but the lipid alteration induced by hemagglutinin was similar to the diphtheria toxin effect. These observations imply that the membrane perturbation induced by diphtheria toxin may be caused by a combination of pore formation and insertion of hydrophobic peptide of toxin to the membrane as well. Additionally, we found that the diphtheria toxin increased the HepG2 cells permeability but the cells viability was maintained at high level at the same time. DNA fragmentation which is related to apoptosis was not induced by the toxin. Under these conditions, we could demonstrate that the lipid alteration of HepG2 cells was brought about by diphtheria toxin at acidic pH.

• Membrane Journal
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• v.25 no.5
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• pp.406-414
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• 2015

In this study, partially fluorinated cation exchange membranes were prepared by direct sulfonation of Poly(VDF-co-hexafluoropropylene) copolymers (PVDF-co-HFP) followed by a casting method for application in the Membrane capacitive deionization (MCDI). The structure of sulfonated PVDF-co-HFP (SPVDF) was confirmed by Fourier-transform infrared (FT-IR) and $^1H$ Nuclear magnetic resonance ($^1H$ NMR) analysis. For quantitative analysis of the chemical composition, the X-ray Photoelectron Spectroscopy (XPS) was used. The membrane properties such as water uptake, ion exchange capacity and electrical resistance were measured. It was suggested that the optimum direct sulfonation condition of PVDF-co-HFP ion exchange membranes was $60^{\circ}C$ and 7 hours for temperature and duration of sulfonation, respectively. The water uptake of the SPVDF ion exchange membrane was 21.5%. The ion exchange capacity and electrical resistance were 0.89 meq/g and $3.70{\Omega}{\cdot}cm^2$, respectively. It was investigated that if it is feasible to apply these membranes in MCDI at various cell potentials (0.9~1.5 V) and initial flow rates (10~40 mL/min). In the MCDI process, the maximum salt removal rate was 62.5% in repeated absorption-desorption cycles.

• Ocean Science Journal
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• v.41 no.4
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• pp.221-226
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• 2006

More attention has been paid to the research on decolorization of dyeing wastewater nowadays. In this study, an investigation into the decolorization of dyeing wastewater was conducted using a combination of coagulant, carboxymethyl chitosan (NOCC) and coagulant aid, polyscrylamide (PAM). The factors influencing the decolorization efficiency, such as pH value, coagulant and the dosages of coagulant, were discussed. The results showed that using PAM as coagulant aid could reach a high decolorization efficiency compared with using NOCC alone. The optimal conditions were pH 2.3, 480 mg/L for NOCC, and 4-8 mg/L for PAM. Under the optimum conditions, the rate of decolorization could achieve 99%, and the removal of chemical oxygen demand (COD) could achieve 90%. In addition, the membrane processes with chitosan/rare-earth-metals could enhance the decolorization rate of Direct Black FF to 94.7%, and Indanthren Red F3B to 98.2%, respectively.

• Macromolecular Research
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• v.12 no.2
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• pp.145-155
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• 2004

Facilitated transport membranes for the separation of olefin/paraffin mixtures have long been of interest in separation membrane science because olefins, such as propylene and ethylene, which are important chemicals in petrochemical industries, are currently separated by energy-intensive cryogenic distillation processes. Recently, solid polymer electrolyte membranes containing silver ions have demonstrated remarkable performance in the separation of olefin/paraffin mixtures in the solid state and, thus, they can be considered as alternatives to cryogenic distillation. Here, we review recent progress, and critical issues affecting in the use of facilitated olefin transport membranes; in particular, we provide a general overview with reference to carrier properties, transport mechanisms, and separation performance.

• Mass Spectrometry Letters
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• v.9 no.3
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• pp.67-72
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• 2018

Alkaline phosphatase (AP) is a membrane-bound glycoprotein that is widely distributed in the plasma membrane of cells of various organs and also found in many organisms from bacteria to humans. The complete amino acid sequence and three-dimensional structure of human placental alkaline phosphatase have been reported. Based on the literature data, AP consists of two presumptive glycosylation sites, at Asn-144 and Asn-271. However, it only contains a single occupied N-linked glycosylation site and no occupied O-linked glycosylation sites. Hydrophilic interaction chromatography (HILIC) has been primarily employed for the characterization of the glycan structures derived from glycoproteins. N-glycan structures from human placental alkaline phosphatase (PLAP) were investigated using HILIC-Orbitrap MS, and subsequent data processing and glycan assignment software. 16 structures including 10 sialylated N-glycans were identified from PLAP.

• Proceedings of the Membrane Society of Korea Conference
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• 1996.10a
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• pp.12-17
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• 1996

The structure formation by liquid-liquid(L-L) phase separation coupled with crystallization in isotactic polypropylene(i-PP). solutioos was investigated by a temperature jump experiment. A series of dialkyl phthalates with a different number of carbon atoms in the alkyl chain was used to control the interaction between polymer and solvent. Various thermal quench conditions were applied to the i-PP solutions to control systematically L-L phase separation and crystallization. A slow crystallizatina elongates the liquid droplets in the radial direction of a spherulite. A rapid crystallization under the deep quench locks-in the growth of L-L phase separation. These results indicate that the extent of L-L phase separation which exists below melting point can be successfully controlled through the proper selection of solvent and thermal conditions.

• Journal of the Korean Chemical Society
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• v.17 no.3
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• pp.213-223
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• 1973

This report has been focused on the studies of the hydraulic pressure distribution which is created by the agitation of the both liquids, dialysing solution and solvent, on either side of the dialysis membrane surface. Agitators of the both liquids have been investigated and developed which can counterbalance the hydraulic pressures. The effects of the agitation velocities on the dialysing velocity have been studied under the conditions which allow the uniform dialysis on the whole surface of the dialysis membrane. Each agitation velocity of the dialysing solution and solvent, at which the dialysis coefficient is obtained most precisely, has been determined.