• Journal of Applied Biological Chemistry
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• v.63 no.1
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• pp.35-41
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• 2020

(-)-epigallocatechin-3-gallate (EGGG), a flavonoid found in green tea, is known to have low bioavailability. In this study, we determine whether piperine, a natural bioenhancer, can increase the absorption rate of EGCG. Using a Caco-2 cell monolayer, permeability experiments were performed in Hanks' balanced salt solution (HBSS) and EGCG stability was adjusted to pH 6.5 and pH 5.5 by ascorbic acid treatment. When HBSS was adjusted to pH 6.5, EGCG remained at 94.78% for up to 2 h and remained at 86.04% after 4 h and the net efflux decreased compared to the control. As a result, uptake was significantly increased in the piperine co-administered group compared to the EGCG-alone group, showing that piperine increased the permeability of EGCG in the Caco-2 cell monolayer. These results suggest that piperine inhibits EGCG glucuronidation and efflux, allowing for greater absorption of EGCG.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1090-1097
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• 1998

Lidocaine compounds have widely been used as local anesthetics. Regarding the molecular mechanism for anesthesia by lidocaine, it is proposed that lidocaine molecules penetrate to the hydrophobic region of cell membrane and expand the membrane volume, producing a change in protein conformation that blocks sodium permeability or lidocaine molecules directly adsorb into lidocaine receptor in the protein channel without expanding the cell membrane. But these proposals have never been proven experimentally. In this study, the expansion of cell membrane by lidocaine compounds was investigated by employing lipid monolayer at the air/water interface as the mimetic system of cell membrane. It was found that oil-soluble lidocaine contracted the area/molecule of lipid in the monolayer of phosphatidyl choline, sphingomyelin, DS-PL95E and lipoid, but expanded the monolayer of phosphatidyl ethanolamine only in a certain range of mixing ratios. On the contrary, water-soluble lidocaine-HCl salt expanded the monolayers of all lipids used in this study.

• Journal of Pharmaceutical Investigation
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• v.40 no.6
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• pp.321-332
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• 2010

Growing interest in the nasal route as a drug delivery system calls for a reliable in vitro model which is crucial for efficiently evaluating drug transport through the nasal cells. Various in vitro cell culture systems has thus been developed to displace the ex vivo excised nasal tissue and in vivo animal models. Due to species difference, results from animal studies are not sufficient for estimating the drug absorption kinetics in humans. However, the difficulty in obtaining reliable human tissue source limits the use of primary culture of human nasal epithelial cells. This shortage of human nasal tissue has therefore prompted studies on the "passage" culture of nasal epithelial cells. A serially passaged primary human nasal epithelial cell monolayer system developed by the air-liquid interface (ALI) culture is known to promote the differentiation of cilia and mucin gene and maintain high TEER values. Recent studies on the in vitro nasal cell culture systems for drug transport studies are reviewed in this article.

• Journal of the Korean Physical Society
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• v.81
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• pp.133-138
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• 2022

Using the first principles calculations, we investigated the strain dependent magnetic properties of the 1T-VSe₂ monolayer (up to ± 3%). We obtained a metallic band structure, and this feature was preserved under both compressive and tensile strain. The pristine system had a magnetic moment of 0.9 µ_B/unit cell and decreased to 0.68 µ_B/unit cell under - 3% compressive strain whereas it was increased to 1.03 µ_B/unit cell under + 3% tensile strain. The 1T-VSe₂ monolayer had an in-plane magnetic anisotropy with a value of - 0.48 meV/cell. The in-plane anisotropy features were maintained in both compressive and tensile strains. The orbital resolved magnetic anisotropy indicated that the V atom contributed to the perpendicular magnetic anisotropy while the Se atom had an in-plane anisotropy. We found that the Se dominated the anisotropy. We also calculated the temperature dependent Curie temperature (T_C). The pristine structure had a T_C of 260 K, and the strain effect enhanced the T_C. Particularly, the compressive strain affected further the exchange parameter resulting in substantial enhancement of the Curie temperature where a T_C of 570 K was achieved at - 3% strain. Our finding regarding the strained VSe₂ could help for further investigation in spintronics and straintronics applications.

• Fisheries and Aquatic Sciences
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• v.19 no.2
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• pp.9.1-9.7
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• 2016

This study was conducted to identify the general conditions for the isolation and in vitro culture of ovary-derived cells in rockfish (Sebastes schlegeli). The effects of three different enzymes on cell retrieval from ovarian tissues were evaluated first, and then the ovary-dissociated cells were cultured under various culture conditions, with varying basal media and culture temperatures, addition of growth factors, and/or culture types. We found that collagenase type I treatment was effective for cell isolation from ovarian tissues. From a total of 42 trials to evaluate the effects of basal media and culture temperatures on cell culture of ovary-dissociated cells, we observed that Leibovitz's L15 medium was more supportive than Dulbecco's modified Eagle's medium for culture, and the cells could grow at all three temperatures tested, 15, 20, and $25^{\circ}C$, at least up to passage 2. However, growth factor addition did not improve cell growth. Introduction of suspension culture after monolayer culture expanded the culture period significantly more than did monolayer culture alone. Our results may provide a basis for developing an in vitro system for S. schlegeli germline cell culture, which will ultimately lead to improvement of the species.

• Reproductive and Developmental Biology
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• v.29 no.4
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• pp.241-245
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• 2005

Porcine oviduct epithelial cells (POEC) are widely used in co-culture experiments to improve early embryonic development, in vitro fertilization in embryo transfer programs for domestic animals and in vitro maturation of immature germ cells. POEC were mechanically isolated and cultured in tissue culture medium 199. Cells grew continuously, and confluent monolayers were formed after 7 days. After forming confluent monolayer of epithelial cells, supernatant was collected as the condition medium for maturing round spermatids in vitro. Round spermatids were also separated mechanically and cultured in the POEC condition medium. In this study we observed that $20\%$ of round spermatid cultured were matured into elongating spermatid after 24 h, and about $10\%$ of round spermatid cultured showed complete elongation (elongated spermatid) within $24\~48$ h of in vitro culture. No further development was observed within $50\~72$ h and transformed cells lost their viability after 72 h. These preliminary findings suggest that the condition medium from POEC may be possible to overcome the round spermatid block by improving the milieu of culture system.

• Biomedical Science Letters
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• v.12 no.3
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• pp.153-160
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• 2006

Human colon cancer is the second most fatal disease among a variety of cancers to cause cancer death in U.S.A. and its incidence rate is currently increased in Korea. Recently, many studies have been being progressed on the efficacy of diverse combination treatments. But results of these studies in vitro were not similar those in vivo. This study compared the anticancer reactions between each use of arsenic trioxide and taxol against human colon cancer HT-29 cell line and combined use of two drugs. And these results compared with the results of HT-29 spheroid cells having similar characteristics to the solid tumor in vivo. The spheroid of HT-29 cells was formed by using a multicellular spheroid system and the result was observed through electron microscopy. In vitro cytotoxicity of each use of arsenic trioxide and taxol was evaluated in HT-29 monolayer cells. The $IC_{50}$ value for arsenic trioxide was to be $33{\mu}M$ and taxol was to be 18nM. The result treated with the combination of taxol and arsenic trioxide decreased the cytotoxicity on the HT-29 monolayer cells. The spheroid cells represented higher resistance against drugs than the monolayer cells. I demonstrated DNA fragmentation after incubation with concentrations more than $10{\mu}M$ arsenic trioxide and 100nM taxol for 48h, on the monolayer cells. But the results of HT-29 cell line treated with the combination of taxol and arsenic trioxide was the same as the outcome of control samples that were not treated with any drug. And I don't demonstrated DNA fragmentation on the spheroid cells. These results suggest that apoptosis was not induced in the use of the combination can be thought as that arsenic trioxide might work as an antagonist to inhibit a taxol mechanism to induce apoptosis. And the spheroid cells represented higher resistance against drugs than the monolayer cells.

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.53-62
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• 1996

Transepithelial transport of tetraethylammonium (TEA) was studied in monolayers of opossum kidney cells cultured on permeable membrane filters. $[^{14}C]-TEA$ was transported across the OK cell monolayer from basolateral to apical side by a saturable process which can be stimulated by acidification of the apical medium. The apparent Michaelis-Menten constant $(K_{m})$ and the maximum velocity$(V_{max})$ for the transport were $41\;{\mu}M$ and 147 pmole/ mg protein/ min, respectively. The transport was significantly inhibited by unlabelled TEA, amiloride, cimetidine, choline, and mepiperphenidol added to the basolateral side at 1 mM and was slightly inhibited by 5 mM $N_{1}-methylnicotinamide\;(NMN).$ Unlabelled TEA added to the apical side stimulated the $basolateral-to-apical\;{^{14}C}-TEA$ transport, suggesting that the TEA self-exchange mechanism was involved at the apical membrane. Sulfhydryl reagents such as ${\rho}-chloromercuribenzoic\;acid\;(PCMB)\;and \;{\rho}-chloro-mercuribenzene\;sulfonate \;(PCMBS)$ and carboxyl reagents such as N,N'-dicyclohexylcarbodiimidem (DCCD) and N-ethoxy-carbonyl-2-ethoxy-1,2-dihydro-quinoline(EEDQ) inhibited the TEA transport at both the basolateral and apical membranes of the OK cell monolayer. These results suggest that OK cell monolayers possess a vectorial transport system for organic cations which is similar to that for organic cation secretion in the renal proximal tubule.

• Korean Journal of Animal Reproduction
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• v.14 no.1
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• pp.73-83
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• 1990

These studies were carried out to find the proper conditions for in vitro maturation and fertilization of bovine follicular oocytes and culture methods capable of further developing early embryos. For these objectives, the cleavage rate of oocytes matured and fertilized in vitro was investigated under medium supplemented with hormones and estrous cow serum and season of oocytes collection as well as different cumulus cell stage before insemination. Finally, 2~8 cell embryos were cultured in in vitro and in vitro culture system to investigate developmental capacity into morula. 1. Cleavage rate of oocytes matured in vitro was 27%(20/73) for A(LH＋FSH＋estradil-17$\beta$＋10% FBS), 38%(27/71) for B(LH＋10% ECS) and 27%(15/56) for C(10% ECS), respectively. Supplement B showed more higher rate and 4~8 cell embryos were also obtained much more in this group(67%, 18/27). In vitro maturation rate of follicular oocytes cultured in TCM 199 supplemented withLH and 10% ECS was 88%(75/85). 2. Cleavage rate(15%, 10/65) of oocytes collected in summer was significantly lower than in fall(47%, 42/89). 3. Cleavage rate(15%, 10/65) of oocytes collected in summer was significantly lower than in fall(47%, 42/89). 3. Cleavage rate(15%, 10/65) of oocytes with partially removed cumulus cell before insemination was more higher than that(44%, 27/62) of oocytes with intact cumulus cell. 4. The frequency of development from early cleaved embryos into morula was 6%(4/65), 12%(4/33) for co-culture of cumulus cell monolayer and bovine oviduct epithelial cell monolayer, respectively and 25%(6/25) in ligated rabbit oviduct.

• Journal of Biomedical Engineering Research
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• v.36 no.1
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• pp.1-6
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• 2015

This study aims to design a monolayer cell adsorption apparatus that would help to produce high-quality slides for Liquid-Based Cytology (LBC) of an early cancer diagnosis for human bodies. The LBC collects exfoliated cells of human bodies and spreads the cells on the slides. Through processes of dyeing and cytological examination, the LBC screens for cancers in early stage. In this study, both of a cell suction module and a cell adsorption module, which are the key elements of the monolayer cell adsorption apparatus, were developed, and using those modules, the study set, first, conditions to help both GYN and NON-GYN apply principal cells without de-endothelialization before conducting its own analysis on the utility. As a results, for GYN, apparatus was determined to be able to produce high-quality slides under the condition of 4 and for NON-GYN, the apparatus would come up with other slides of high-quality under the condition of 2. The study carried out a repetitive test on selected conditions and proved 96% of the repetitive success rate. By the results of what has been learned so far, the study presents that the apparatus has a possibility to replace device from South Korea as one of those other currently-applied systems to run the LBC and that the system will also present a new paradigm for cancer diagnosis as it makes a contribution to the improvement in the LBC.