• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.1 s.32
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• pp.38-50
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• 2007

Object : We investigated the effect of Gamiokyaek-tang(GOYT) on immediate type hypersensitivity. Methods : We investigated anti-dinitrophenyl(DNP) IgE-mediated passive cutaneous anaphylaxis(PCA) and acetic acid-induced vascular permeability in rodents. Also we measured MTT assay, ${\beta}-hexosminidase$ activity and IL-4 from RBL-2H3 and nitric oxide from Raw264.7. Results : GOYT inhibited passive cutaneous anaphylaxis and acetic acid-induced vascular permeability by oral administration. All the concentrations of GOYT from 0.1 to 5mg/ml didn't have an effect on cell viability and cytotoxicity. In RBL-2H3, ${\beta}-hexosminidase$ release and IL-4 production were significantly reduced by 1, 2 and 5mg/ml of GOYT. In Raw264.7, nitric oxide level was decreased by 5mg/ml of GOYT. Conclusion : These results indicate that GOYT have inhibition effects on immediate type hypersensitivity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.409-411
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• 2005

A series of inorganic-organic hybrid membranes were prepared with a systematic variation of titanium dioxidenanoparticles content. Their water uptake, methanol permeability and proton conductivity as a function of inorganic oxide content were investigated. The results obtained show that the inorganic oxide network decreases the proton conductivity and water swelling. It is also found that increase in inorganic oxide content leads to decrease of methanol permeability. In terms of the morphology, membranes are homogeneous and exhibit a good adhesion between inorganic domains and the polymer matrix. The properties of the composite membranes are compared with the standard nation membrane.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.234.3-235
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• 2003

The aim of this study is to evaluate the permeability of PEG-conjugated salmon calcitonin (sCT) across monolayers of Caco-2 cells that represent a model of the intestinal barrier. Caco-2 cells were grown to confluency on a permeable polycarbonate membrane to permit transport through it. Permeability experiments were performed with native-sCT and PEG-conjugated sCT (PEG M.W. 2000) at various concentrations (5uM, 10uM, 25uM, 50uM, 100uM) in the apical to basolateral direction. The barrier properties were assessed by detecting transport of markder molecules ($^3$H-mannitol) and by measuring transepithelial electrical resistance (TEER). (omitted)

• Molecules and Cells
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• v.37 no.11
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• pp.785-794
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• 2014

Mitophagy, a cellular process that selectively targets dysfunctional mitochondria for degradation, is currently a hot topic in research into the pathogenesis and treatment of many human diseases. Considering that hypoxia causes mitochondrial dysfunction, which results in cell death, we speculated that selective activation of mitophagy might promote cell survival under hypoxic conditions. In the present study, we introduced the Regulator of calcineurin 1-1L (Rcan1-1L) to initiate the mitophagy pathway and aimed to evaluate the effect of Rcan1-1L-induced mitophagy on cell survival under hypoxic conditions. Recombinant adenovirus vectors carrying Rcan1-1L were transfected into human umbilical vein endothelial cells and human adult cardiac myocytes. Using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay and Trypan blue exclusion assay, Rcan1-1L overexpression was found to markedly reverse cell growth inhibition induced by hypoxia. Additionally, Rcan1-1L overexpression inhibited cell apoptosis under hypoxic conditions, as detected by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) apoptosis assay. Meanwhile, the mitochondria-mediated cell apoptotic pathway was inhibited by Rcan1-1L. In contrast, knockdown of Rcan1-1L accelerated hypoxia-induced cell apoptosis. Moreover, Rcan1-1L overexpression significantly reduced mitochondrial mass, decreased depolarized mitochondria, and downregulated ATP and reactive oxygen species production. We further delineated that the loss of mitochondrial mass was due to the activation of mitophagy induced by Rcan1-1L. Rcan1-1L overexpression activated autophagy flux and promoted translocation of the specific mitophagy receptor Parkin into mitochondria from the cytosol, whereas inhibition of autophagy flux resulted in the accumulation of Parkin-loaded mitochondria. Finally, we demonstrated that mitochondrial 1permeability transition pore opening was significantly increased by Rcan1-1L overexpression, which suggested that Rcan1-1L might evoke mitophagy through regulating mitochondrial permeability transition pores. Taken together, we provide evidence that Rcan1-1L overexpression induces mitophagy, which in turn contributes to cell survival under hypoxic conditions, revealing for the first time that Rcan1-1L-induced mitophagy may be used for cardioprotection.

• Membrane Journal
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• v.21 no.3
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• pp.247-255
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• 2011

In this study, to obtain good dispersity of graphene which has excellent conductivity and mechanical strength, the graphene was modified by two different methods. Then the SPAES/graphene hybrid membranes were fabricated from different graphene contents. We compared performance of composite membrane with different preparing method of graphene and content of modified graphene. The morphology of the composite membranes has been investigated using SEM. Chemical structure of modified graphene was analyzed using by FT-IR and EDX. The proton conductivity and methanol permeability of the hybrid membranes were studied with changing graphene content from 0.5 to 3.0 wt.%. The SPAES/modified graphene composite membranes showed high proton conductivity (0.21 S/cm) compared with the SPAES membrane (0.09 S/cm) at $80^{\circ}C$ and 100% relative humidity condition. And the methanol permeability was decreased linearly as the content of modified graphene increased from 0 to 1.5 wt%.

• Journal of Pharmaceutical Investigation
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• v.29 no.4
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• pp.329-335
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• 1999

Clenbuterol, a selective ${\beta}_2-adrenergic$ receptor stimulant, has been introduced as a potent bronchodilator for patients with bronchial asthma, chronic bronchitis and pulmonary emphysema. For the purpose of developing a transdermal preparation for clenbuterol, we attempted to select an optimal solvent system and permeation enhancer among fatty acids and fatty alcohols which are known to accelerate the penetration of various drugs in permeation experiments using hairless mouse skin and Franz diffusion cell. Apparent partition coefficient of clenbuterol was increased as pH of buffer solution was increased and solubility of clenbuterol was increased as the percent of propylene glycol(PG) in buffer solution(pH 10) was increased. Permeability of clenbuterol from different buffer(pH 10)/PG solvent mixtures was decreased as the percent of PG in pH 10 buffer solution was increased and among the various enhancers studied, lauryl alcohol was found to be the most effective enhancer, increasing the permeability of clenbuterol approximately 76-fold compared with control. Lauryl alcohol$(0{\sim}2%)$ enhanced the permeability of clenbuterol concentration-dependently. In this study, the optimal solvent system for the penetration of clenbuterol was found to be 50/50 buffer(pH 10)/PG solvent mixture containing 2% lauryl alcohol.

• Membrane Journal
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• v.15 no.1
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• pp.1-7
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• 2005

Polymer electrolyte membranes containing polysilsesquioxane (PSQ) spheres were prepared with the blend of sulfonated poly(ether ether ketone) (SPEEK) (60%) and poly(ether sulfone) (PES) (40%). The amount of PSQ spheres was fixed at 10 wt%. The prepared polymer electrolyte membranes were characterized in terms of methanol permeability, proton conductivity, and ion exchange capacity. In all cases, both methanol permeability and proton conductivity of the polymer electrolyte membranes containing PSQ spheres were lower than the values of Nafion 117 and higher than those of SPEEK/PES (6:4) blend without PSQ spheres. The experimental results indicated that the polymer electrolyte membranes containing MS64 and VTMOS spheres were the best choice in terms of the ratio of proton conductivity to methanol permeability.

• Journal of Korean Academy of Oral Health
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• v.42 no.4
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• pp.224-228
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• 2018

Objectives: As a first step to study the anticaries effect of ethanol alone, we investigated the effects of ethanol on the expression levels of the atpB gene and proton permeability of Streptococcus mutans in suspension cultures. Methods: S. mutans UA159 was grown in brain heart infusion medium at either pH 4.8 or 6.8. The total extracted RNA was reverse-transcribed into cDNA using a $Superscript^{TM}$ First-Strand Synthesis System. The resulting cDNA and negative controls were amplified by ABI PRISM 7700 real-time PCR system with SYBR Green PCR Master Mix. For proton flux assay, bacterial suspensions were titrated to pH 4.6 with 0.5 M HCl, and then additional 0.5 M HCl was added to decrease the pH values by approximately 0.4 units. The subsequent increase in pH was monitored using a glass electrode. Ten percent (v/v) butanol was added to the suspensions at 80 min to disrupt the cell membrane. Results: In a concentration-dependent manner, ethanol alone not only decreased the growth rate of S. mutans and the expression of the atpB gene but also increased the proton permeability at both pH 4.8 and 6.8. Conclusions: These findings suggest that ethanol has the potential for an anticaries ingredient. We believe that ethanol may be used together with fluoride and/or other cariostatic agents in order to develop better anticaries toothpastes and/or mouthrinses.

• Composites Research
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• v.37 no.1
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• pp.40-45
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• 2024

In this research, we introduce a novel approach that employs a 3D convolutional neural network (CNN) model to predict the permeability of Gas Diffusion Layers (GDLs). For training the model, we create an artificial dataset of GDL representative volume elements (RVEs) by extracting morphological characteristics from actual GDL images obtained through X-ray tomography. These morphological attributes involve statistical distributions of porosity, fiber orientation, and diameter. Subsequently, a permeability analysis using the Lattice Boltzmann Method (LBM) is conducted on a collection of 10,800 RVEs. The 3D CNN model, trained on this artificial dataset, well predicts the permeability of actual GDLs.

• Korean Journal of Materials Research
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• v.12 no.9
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• pp.691-695
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• 2002

A low temperature anode-supported tubular solid oxide fuel cell was developed. The anode-supported tube was fabricated using extrusion process. Then the electrolyte layer and the cathode layer were coated onto the anode tube by slurry dipping process, subsequently. The anode tube and electrolyte were co-fired at $140^{\circ}C$, and the cathode was sintered at $1200^{\circ}C$. The thickness and gas permeability of the electrolyte depended on the number of coating and the slurry concentration. Anode-supported tube was satisfied with SOFC requirements, related to electrical conductivity, pore structure, and gas diffusion limitations. At operating temperature of $800^{\circ}C$, open circuit voltage of the cell with gastight and dense electrolyte layer was 1.1 V and the cell showed a good performance of 450 mW/$\textrm{cm}^2$.