• Microbiology and Biotechnology Letters
• /
• v.45 no.2
• /
• pp.110-117
• /
• 2017

The anti-inflammatory effect of Sargassum patens C. Agardh ethanol extract (SPEE) was examined based on the lipopolysaccharide (LPS)-induced inflammatory response in this study. SPEE treatment was not cytotoxic to macrophages compared to the control. The production of NO was suppressed by SPEE by approximately 28% at $100{\mu}g/ml$, and levels of interleukin-6, tumor necrosis $factor-{\alpha}$, and $interleukin-1{\beta}$ decreased in a dose-dependent manner. In addition, the expression of inducible nitric oxide synthase, cyclooxygenase-2, and nuclear $factor-{\kappa}B$ was suppressed by SPEE treatment. In vivo, croton oil-induced mouse ear edema was attenuated by SPEE and the infiltration of mast cells into the tissue decreased. Based on these results, SPEE inhibits the release of LPS-induced pro-inflammatory cytokines and mediators, suggesting that SPEE is a potential agent for anti-inflammatory therapies.

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.7
• /
• pp.712-720
• /
• 2008

Sediment and interstitial water samples from ten lagoons in the Northeastern coastal part of South Korea were analyzed to obtain the concentrations of metals and inorganic ligand. These data, coupled with pH and ionic strength, were used to compute the aqueous speciation of the metals in the interstitial water using the MINTEQA2 equilibrium program. The K and Na were almost entirely present as the free aqua ions, but Co, Cd, Ni, Pb and Zn were existed as various metal-ligand complexes. Metals such as Al, As, and Cr formed 3$\sim$4 metal-ligand complexes. In the interstitial water with high chloride concentrations, almost all of the metals were dominated by free aqua ions. Metals of Cd, Co, Ni, Pb and Zn were bound as chloride-metal complexes of the type M$^{x+}$ + xCl$^-$, and Fe, Mn and Mg were dominated by sulfate equilibria(M$^{2+}$ + SO$_4{^{2-}}$). Hg(II) was speciated as HgCl$_2$(aq), HgCl$_3{^-}$ and HgCl$_4{^-}$. However, in the interstitial water with low chloride concentrations, Hg(II) and Cd(II) were existed as chloride-metal complexes, metals of Cu, Mg, Mn, Ni, Pb and Zn were dominated by sulfate equilibria, and the speciation of Fe(II) was bound as Fe(OH)$_2{^+}$, Fe(OH)$_3$(aq). However, Al, As and Cr were dominated by hydroxy-metal and oxide-metal species in nearly all of the lagoons.

• Journal of Nutrition and Health
• /
• v.53 no.5
• /
• pp.452-463
• /
• 2020

Purpose: Aster tataricus (AT) is one of the Asteraceae perennial herbs used in traditional Chinese medicine. The herb contains various bioactive substances, such as flavonoids, isoflavonoids, and phenolic compounds in the roots, and exhibits a range of effects including anti-bacterial, anti-oxidant, and anti-inflammatory activities. This study compared the immunomodulatory effects of ethanol and water extracts of whole AT, except the roots, and analyzed the molecular mechanisms for the regulatory effects on cytokine secretion from THP-1 cells. Methods: The effects of AT extract on the cell viability and proliferation of THP-1 cells were analyzed using the Cell Counting Kit-8 method. The concentrations of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the cell culture supernatant of the AT-treated THP-1 cells were measured using an enzyme-linked immunosorbent assay. The protein levels of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), inhibitor of nuclear factor kappa B (IκBα), and mitogen-activated protein kinase (MAPK) phosphorylation in the cell lysates were determined by western blotting. Results: The water extract and the ethanol extract of AT did not affect the cell viability, and increased the proliferation of THP-1 cells significantly compared to the vehicle. The water extract increased the secretion of IL-1β from THP-1 cells in a dose-dependent manner, but the ethanol extract had no effect. The expression of COX-2 and iNOS protein and the phosphorylation of MAPK and Akt were induced in AT-treated cells. In addition, IκBα was degraded by AT in a concentration-dependent manner. IL-1β secretion by AT was reduced by extracellular-signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) inhibitors, while TNF-α secretion was decreased by inhibitors of ERK, p38 MAPK, and JNK. Interestingly, the p38 MAPK inhibitor increased the production of IL-1β by AT further. Conclusion: The water extract of the above-ground parts of AT contains immunomodulatory bioactive substances that stimulate immune cells through the MAPK signaling pathway.

• Restorative Dentistry and Endodontics
• /
• v.32 no.5
• /
• pp.419-425
• /
• 2007

The aim of this study was to evaluate the radiopacity and cytotoxicity of three resin-based (AH 26, EZ fill and AD Seal), a zinc oxide-eugenol-based (ZOB Seal), and a calcium hydroxide-based (Sealapex) root canal sealers. Specimens, 10 mm in diameter and 1 mm in thickness, were radiographed simultaneously with an aluminum step wedge using occlusal films, according to ISO 6876/2001 standards. Radiographs were digitized, and the radiopacity of sealers was compared to the different thicknesses of the aluminum step wedge, using the Scion image software. Using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of each material was determined in immortalized human periodontal ligament (IPDL) cells. The results demonstrated that EZ fill was the most radiopaque sealer, while Sealapex was the least radiopaque (p < 0.05). AH 26, AD Seal and ZOB Seal presented intermediate radiopacity values. All the materials evaluated, except for Sealapex, presented the minimum radiopacity required by ISO standards. The cell viabilities of resin-based root canal sealers were statistically higher than that of other type of root canal sealers through the all experimental time. Further, EZ fill showed statistically lower cell viability in 24 and 48 hours compared to AD Seal and in 72 hours compared to all other resin-based root canal sealers. However, there was no correlation between the radiopacity and cytotoxicity of three resin-based root canals sealers (p > 0.05). These results indicate that resin-based root canal sealer is more biocompatible and has advantage in terms of radiopacity.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.30 no.1
• /
• pp.62-71
• /
• 1997

The apparent nutrient digestibilities were examined by using chromic oxide indicator according to the various fecal collection methods in juvenile and adult Korean rockfish (Sebastes schlegeli). Feces were collected from three replicate groups of fish by dissection, stripping or decantation using fecal collector attached to fish rearing tank, respectively. The digestibilities of dry matter, protein, lipid, and energy were affected by fecal collection methods (P<0.01), but not affected by fish size. The digestibilities of nutrient determined by stripping or decantation methods were significantly higher than those determined by dissection method (P<0.01). No significant differences in the digestibilities of protein, lipid and energy were found between the stripping and decantation methods in adult fish (P>0.01). The digestibilities of dry matter, protein, lipid, energy, nitrogen-free extract, and total amino acids in juvenile and adult fish were 58, 93, 94, 79, 32, and $93\%$, and 61, 94, 96, 80, 29, and $94\%$, respectively, when they were measured by decantation method. Methionine, cystine and valine digestibilities were significantly lower than those of other amino acids in both juvenile and adult fish (P<0.01). Results indicate that stripping or decantation with fecal collector could be a reliable digestibility procedure for measuring the nutrient digestibilities in Korean rockfish.

• Korean Chemical Engineering Research
• /
• v.58 no.4
• /
• pp.541-549
• /
• 2020

The Drug Delivery System (DDS) is defined as a technology for designing existing or new drug formulations and optimizing drug treatment. DDS is designed to efficiently deliver drugs for the care of diseases, minimize the side effects of drug, and maximize drug efficacy. In this study, the optimization of tripolyphosphate (TPP) concentration on the size of Chitosan nanoparticles (CNPs) produced by crosslinking with chitosan was measured. In addition, the characteristics of Fe₃O₄-CNPs according to the amount of iron oxide (Fe₃O₄) were measured, and it was confirmed that the higher the amount of Fe₃O₄, the better the characteristics as a magnetic drug carrier were displayed. Through the ninhydrin reaction, a calibration curve was obtained according to the concentration of γ-aminobutyric acid (GABA) of Y = 0.00373exp(179.729X)-0.0114 (R² = 0.989) in the low concentration (0.004 to 0.02 wt%) and Y = 21.680X-0.290 (R² = 0.999) in the high concentration (0.02 to 0.1 wt%). Absorption was constant at about 62.5% above 0.04 g of initial GABA. In addition, the amount of GABA released from GABA-Fe₃O₄-CNPs over time was measured to confirm that drug release was terminated after about 24 hr. Finally, GABA-Fe₃O₄-CNPs performed under the optimal conditions were spherical particles of about 150 nm, and it was confirmed that the properties of the particles appear well, indicating that GABA-Fe₃O₄-CNPs were suitable as drug carriers.

• Resources Recycling
• /
• v.12 no.6
• /
• pp.38-46
• /
• 2003

In this study, nano-sized Ni-ferrite and $Fe_2$$O_3$＋NiO powder was fabricated by spray pyrolysis process in the condition of 1kg/$\textrm{cm}^2$ air pressure using the Fe-Ni complex waste acid solution generated during the manufacturing process of shadow mask. The average particle size of the produced powder was below 100 nm. The effects of the reaction temperature, the concentration of raw material solution and the nozzle tip size on the properties of powder were studied. As the reaction temperature increased from $800 ^{\circ}C$ to $1100^{\circ}C$, the average particle size of the powder increased from 40 nm to 100 nm, the structure of the powder gradually became solid, yet the distribution of the particle size appeared more irregular. Along with the increase of the reaction temperature, the fraction of the Ni-ferrite phase were also on the rise, and the surface area of the powder was greatly reduced. As the concentration of Fe in solution increased from 20g/l to 200g/l, the average particle size of the powder gradually increased from 30 nm to 60 nm, while the distribution of the particle size appeared more irregular. Along with the increase of the concentration of solution, tie fraction of the Ni-ferrite phase was on the rise, and the surface area of the powder was greatly reduced. Along with the increase of the nozzle tip size, the distribution of the particle size appeared more irregular, yet the average particle size of the powder showed no significant change. As the nozzle tip size increased from 1 mm to 2 mm, the fraction of the Ni-ferrite phase showed no significant change, while the surface area of the powder slightly reduced. As the nozzle tip size increased to 3 mm and 5 mm, the fraction of the Ni-ferrite phase gradually reduced, and the surface area of the powder slightly increased.

• Korean Journal of Materials Research
• /
• v.5 no.1
• /
• pp.42-54
• /
• 1995

$Ta_2O_5$ thin film IS a promising material for the high dielectrics of ULSI DRAM. In this study, $Ta_2O_5$ thin film was grown on p-type( 100) Si wafer by thermal metal organic chemical vapo deposition ( MCCVD) method and the effect of operating varialbles including substrate temperature( $T_s$), bubbler temperature( $T_ \sigma$), reactor pressure( P ) was investigated in detail. $Ta_2O_5$ thin film were analyzed by SEM, XRD, XPS, FT-IR, AES, TEM and AFM. In addition, the effect of various anneal methods was examined and compared. Anneal methods were furnace annealing( FA) and rapid thermal annealing( RTA) in $N_{2}$ or $O_{2}$ ambients. Growth rate was evidently classified into two different regimes. : (1) surface reaction rate-limited reglme in the range of $T_s$=300 ~ $400 ^{\circ}C$ and (2: mass transport-limited regime in the range of $T_s$=400 ~ $450^{\circ}C$.It was found that the effective activation energies were 18.46kcal/mol and 1.9kcal/mol, respectively. As the bubbler temperature increases, the growth rate became maximum at $T_ \sigma$=$140^{\circ}C$. With increasing pressure, the growth rate became maximum at P=3torr but the refractive index which is close to the bulk value of 2.1 was obtained in the range of 0.1 ~ 1 torr. Good step coverage of 85. 71% was obtained at $T_s$=$400 ^{\circ}C$ and sticking coefficient was 0.06 by comparison with Monte Carlo simulation result. From the results of AES, FT-IR and E M , the degree of SiO, formation at the interface between Si and TazO, was larger in the order of FA-$O_{2}$ > RTA-$O_{2}$, FA-$N_{2}$ > RTA-$N_{2}$. However, the $N_{2}$ ambient annealing resulted in more severe Weficiency in the $Ta_2O_5$ thin film than the TEX>$O_{2}$ ambient.

• Journal of the Korean Vacuum Society
• /
• v.15 no.5
• /
• pp.527-533
• /
• 2006

Spinel $LiNi_xMn_{2-x}O_4$ thin films were synthesized up to x = 0.9 by a sol-gel method employing spin-coating. The Ni-substituted films were found to maintain cubic structure at low x but to exhibit tetragonal structure for $x{\geq}0.6$. Such cubic-tetragonal phase transition indicates that $Ni^{3+}(d7)$ ions with low-spin $(t_{2g}^6,e_g^1)$ state occupy the octahedral sites of the compound, thus being subject to the Jahn-Teller distortion. By x-ray photoelectron spectroscopy both $Ni^{2+}$ and $Ni^{3+}$ ions were detected. Optical properties of the $LiNi_xMn_{2-x}O_4$ films were investigated by spectroscopic ellipsometry (SE) in the visible?ultraviolet range. The measured dielectric function spectra by SE mainly consist of broad absorption structures attributed to charge-transfer (CT) transitions, $O^{2-}(2p){\rightarrow}Mn^{4+}(3d)$ for 1.9 $(t_{2g})$ and $2.8{\sim}3.0$ eV $(e_g)$ structures and $O^{2-}(2p){\rightarrow}Mn^{3+}(3d)$ for 2.3 $(t_{2g})$ and $3.4{\sim}3.6$ eV $(e_g)$ structures. Also, sharp absorption structures were observed at about 1.6, 1.7, and 1.9 eV, interpreted as due to d-d crystal-field transitions within the octahedral $Mn^{3+}$ ion. The strengths of these absorption structures are reduced by the Ni substitution. Rapid reduction of the CT transition strength involving the eg states for x = 0.6 is attributed to the reduced wavefunction overlap between the $e_g$ and the $O^{2-}(2p)$ states due to the tetragonal extension of the lattice constant by the Jahn-Teller effect.

• Journal of the Korean Vacuum Society
• /
• v.21 no.5
• /
• pp.273-278
• /
• 2012

Over the last decade, the hafnium-based gate dielectric materials have been studied for many application fields. Because these materials had excellent behaviors for suppressing the quantum-mechanical tunneling through the thinner dielectric layer with higher dielectric constant (high-K) than $SiO_2$ gate oxides. Although high-K materials compensated the deterioration of electrical properties for decreasing the thickness of dielectric layer in MOSFET structure, their nano-mechanical properties of $HfO_2$ thin film features were hardly known. Thus, we examined nano-mechanical properties of the Hafnium oxide ($HfO_2$) thin film in order to optimize the gate dielectric layer. The $HfO_2$ thin films were deposited by rf magnetron sputter using hafnium (99.99%) target according to various oxygen gas flows. After deposition, the $HfO_2$ thin films were annealed after annealing at $400^{\circ}C$, $600^{\circ}C$ and $800^{\circ}C$ for 20 min in nitrogen ambient. From the results, the current density of $HfO_2$ thin film for 8 sccm oxygen gas flow became better performance with increasing annealing temperature. The nano-indenter and Weibull distribution were measured by a quantitative calculation of the thin film stress. The $HfO_2$ thin film after annealing at $400^{\circ}C$ had tensile stress. However, the $HfO_2$ thin film with increasing the annealing temperature up to $800^{\circ}C$ had changed compressive stress. This could be due to the nanocrystal of the $HfO_2$ thin film. In particular, the $HfO_2$ thin film after annealing at $400^{\circ}C$ had lower tensile stress, such as 5.35 GPa for the oxygen gas flow of 4 sccm and 5.54 GPa for the oxygen gas flow of 8 sccm. While the $HfO_2$ thin film after annealing at $800^{\circ}C$ had increased the stress value, such as 9.09 GPa for the oxygen gas flow of 4 sccm and 8.17 GPa for the oxygen gas flow of 8 sccm. From these results, the temperature dependence of stress state of $HfO_2$ thin films were understood.