• Polymer(Korea)
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• v.38 no.6
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• pp.694-701
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• 2014

In this study, Polygomun aviculare L. (P. aviculare L.) extract loaded elastic liposomes (ELPs) were investigated to enhance the transdermal delivery of P. aviculare L. extract composed of various flavonoids. ELPs were composed of egg phospholipids (PC) and edge activator ($Tego^{(R)}$ care 450) and the physical properties and in vitro permeation studies of ELPs were performed. Particle size ranged from 148.1 to 262.2 nm and deformability index was recorded as 11.5~25.4. Loading efficiency was from 53.1 to 66.3%. In vitro skin permeation studies using Franz diffusion cell demonstrated that ELP-4 having ratio of 85:15 for PC to $Tego^{(R)}$ care 450 exhibited the higher skin permeability than ELP-1, the general liposome without $Tego^{(R)}$ care 450. It was visually seen by fluorescence image restoration microscopy. The findings suggest that ELP-4 selected as the optimal formulation could be used as useful formulation for transdermal delivery of the extract.

• Restorative Dentistry and Endodontics
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• v.32 no.1
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• pp.9-18
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• 2007

The purposes of this study were to examine the variability of adhesive thickness on the different site of the cavity wall when used total-etch system without filler and simplified self-etch system with filler and to evaluate the relationship between variable adhesive thickness and microtensile bond strength to the cavity wall. A class I cavity in six human molars was prepared to expose all dentinal walls. Three teeth were bonded with a filled adhesive, $Clearfil^{TM}$ SE bond ana the other three teeth were bonded with unfilled adhesives, $Scotchbond^{TM}$ Multi Purpose. Morphology and thickness of adhesive layer were examined using fluorescence microscope. Bonding agent thickness was measured at three points along the axial cavity wall edge of cavity margin (rim). halfway down each cavity wall (h1f), internal angle of the cavity (ang). After reproducing the adhesive thickness at rim, h1f and ang, micro-tensile bond strength were evaluated. For both bonding agents, adhesive thickness of ang was significantly thicker than that of rim and h1f (P <0.05). As reproduced the adhesive thickness, microtensile bond strength was increased as adhesive thickness was increased in two bonding agents. Adhesive thickness of internal angle of the cavity was significantly thicker than that of the cavity margin and the halfway cavity wall for both bonding agents. Microtensile bond strength of the thick adhesive layer at the internal angle of the cavity was higher than that of the thin adhesive layer at 1,he cavity margin and the halfway cavity in the two bonding systems.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.1 s.49
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• pp.25-33
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• 2005

Melanocytes synthesize melanin within discrete organelle termed melanosomes which are transferred to the surrounding keratinocytes and can be produced in varying sizes, numbers and densities. Skin whitening products have become increasingly popular in the past few years. The most successful natural skin whitening agents are: arbutin, vitamin C, kojic acid, and mulberry, which are all tyrosinase inhibitors. In this work, melanoston, a melanogenesis inhibitor isolated from yeast was studied to understand its mechanism of melanogenesis inhibition. It was found that melanoston was not a tyrosinase inhibitor, while when melanoston was applied to the B16 melanoma cell culture media, the intracellular tyrosinase activity was decreased by more than $30\%$. When B16 melanoma was stimulated with $\alpha$-MSH, cell morphololgy was dramatically changed to have lots of dendrites on the cell membrane surface. On the other hand, B16 was treated with $\alpha$-MSH and melanoston, simultaneously, the change of cell morphologv was not so great. This inhibitory effect of melanoston was found to be related to the inhibition of intracellar activation and transportation of tyrosinase, which was observed by irmmunostaining of B16 melanoma using anti-tyrosinase antibody. From these results, melanoston was regarded as an inhibitor to the differentiation of melanoma cells.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.83-89
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• 2022

Since the pandemic of COVID-19, active investigation to develop immunity to infectious disease by delivering nucleic acids has been proceeded. Particularly, many studies have been conducted on non-viral vector as several vital side-effects which were found on nucleic acid delivery system using viral vectors. In this study, we have developed plasmid DNA (pDNA) loaded-hyaluronic acid derivative (HA) coated-polyethyleneimine (PEI) based polyplex for enhanced nucleic acid delivery efficiency. We have optimized the ratio of pDNA : PEI : HA by measuring size and protein transcription efficiency. The final product, polyplex-HA, was characterized through measuring size, zeta-potential and TEM image. Intracellular uptake and protein transcription efficiency were compared to commercially available transfection reagent, lipofectamine, through fluorescence image and flow cytometry. In conclusion, polyplex-HA presents a novel gene delivery system for efficient and stable protein transcription since it is available for delivering various genetic materials and has less immunoreactivity.

• The Journal of the Acoustical Society of Korea
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• v.42 no.5
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• pp.412-421
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• 2023

Ultrasound brain stimulation is spot-lighted by its capability of inducing brain cell activation in a localized deep brain region and ultimately treating impaired brain function while the efficiency and directivity of neural modulation are highly dependent on types of stimulus waveforms. Therefore, to optimize the types of stimulation parameters, we propose a cell-cultivable ultrasonic transducer having a series stack of a spin-coated polymer piezoelectric element (Poly-vinylidene fluoride-trifluorethylene, PVDF-TrFE) and a parylene insulating layer enhancing output acoustic pressure on a glass-coverslip which is commonly used in culturing cells. Due to the uniformity and high accuracy of stimulus waveform, tens of neuronal cell responses located on the transducer surface can be recorded simultaneously with fluorescence microscopy. By averaging the cell response traces from tens of cells, small changes to the low intensity ultrasound stimulations can be identified. In addition, the reduction of stimulus distortions made by standing wave generated from reflections between the transducers and other strong reflectors can be achieved by placing acoustic absorbers. Through the proposed ultrasound transducer, we could successfully observe the calcium responses induced by low-intensity ultrasound stimulation of 6 MHz, 0.2 MPa in astrocytes cultured on the transducer surface.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.1
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• pp.41-54
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• 2023

Illite is a common mineral that forms readily from feldspar and mica via hydrothermal alteration and exhibits various characteristics depending on the degree of hydrothermal alteration. To ensure continued mining of high-quality illite ore, it is crucial to understand the illitization. Thus, this study collected ores from two illite ore deposit and their surrounding alteration zones in Yeongdong-gun, Chungcheongbuk-do, a significant source of illite in the Republic of Korea, to determine the constituent mineral contents and textural characteristics. Polarized light microscopy analyses revealed that the illite ore deposit were highly illitized with little remaining textural characteristics of the parent mica schist, and only some quartz was present. The ore zone contained illite, muscovite, quartz, and feldspar, with illitization primarily occurring around feldspar and quartz. X-ray diffraction analyses identified that the content of illite/muscovite was approximately 50-75 wt.%, with a maximum of 75 wt.%. Additionally, X-ray fluorescence analyses indicated a linear increase in K₂O content with increasing illite content, showing the highest correlation among the major components analyzed. It is suggested that the illite in the Yeongdong area results from feldspar and quartz alteration by hydrothermal fluids along the fault, with illitization of feldspar occurring before that of quartz. The results of this study are expected to contribute to the development of high-quality illite ore deposit in Yeongdong, Chungcheongbuk-do.

• Korean Journal of Animal Reproduction
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• v.24 no.4
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• pp.429-437
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• 2000

This study investigated the successful introduction of genes of erythropoietin (EPO) and enhanced green fluorescent protein (EGFP) in bovine embryos following nuclear transfer of bovine fetal fibroblasts (bFF), which were transfected by retrovirus vector system. Non-starved bFF were, transferred into perivitelline space of enucleated oocytes. The bFF-oocyte units were accomplished by cell to cell fusion and activated with calcium inophore and 6-dimethylaminopurine. Reconstructed embryos were co-cultured with bovine oviduct epithelial cells in CRlaa medium for 8 days. Out of 187 (EPO) and 210 (EGFP) bovine eggs reconstructed by nuclear transfer, 149 (EPO : 80.0%) and 158 (EGFP : 75.2%) embryos were cleaved, and among them 36 (EPO : 24.2%) and 35 (EGFP : 22.2%) embryos developed to the blastocyst stage. Of these blastocysts, 100% integration of EPO gene in 36 embryos was determined by PCR, and 100% expression of EGFP gene in 35 embryos was observed under the fluorescent microscope. This result indicates that bovine oocytes reconstructed by nuclear transfer of transfected bFF can successfully develop to the blastocyst stage. Furthermore, this novel procedure may be presumably an attractive method efficiently to produce the transgenic cattles.

• Analytical Science and Technology
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• v.21 no.1
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• pp.58-63
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• 2008

Nano-sized ZnO crystals were successfully incorporated using ion exchange method in TMA-A zeolite synthesized by the hydrothermal method. The optimal composition for the synthesis of TMA-A zeolite was resulted in a solution of $Al(i-pro)_3$ : 2.2 TEOS : 2.4 TMAOH : 0.3 NaOH : 200 $H_2O$. 0.3 g of TMA-A zeolite and 5 mol of $ZnCl_2$ solution were employed for the preparation of ZnO incorporated TMA-A zeolite. The crystallization process of ZnO incorporated TMA-A zeolite was analyzed by X-ray diffraction (XRD). The incorporated nano-sized ZnO crystals and the crystallinity of TMA-A zeolite were evaluated by transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The size of the incorporated nano-sized ZnO crystals was 3~5 nm, while the TMA-A zeolite was 60~100 nm. The bonding structure and absorption of the ZnO incorporated TMA-A zeolite were compared with the ZnO and TMA-A zeolite by the FT-IR analysis. Subsequentlly, the ZnO incorporated TMA-A zeolite showed the photoluminescent characteristics on the wavelengths of 330~260 nm and 260~230 nm by measurement of UV spectrophotometer.

• Journal of Yeungnam Medical Science
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• v.14 no.2
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• pp.359-369
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• 1997

We studied the expression of the cell surface antigen associated with myeloid and lymphoid leukemias on bone marrow or peripheral blood blast cells from 153 leukemic patients including 61 cases of acute myelogenous leukemias(AML), 46 of acute lymphocytic leukemias(ALL) and 12 of acute leukemias. They were analyzed by direct or indirect immunofluorescence method for reactivity with the monoclonal antibodies to B cells(CD10, CD19, SmIg), T cells(CD2, CD5, CD7, CD3, CD4, CD8), myeloid antigen(CD13, CD14, CD33, CD61) and a nonspecific antigen, HLA-DR. Lymphoid associated markers detected on AML is CD7 32.8%, CD10 14.8%, CD5 13.1%, CD2 6.6% and CD19 1.6%. TdT was positive in 4.9% of AMLs. Hybrid leukemias were 8 cases out 61 AML cases and were mainly composed of monocytic lineage, M4 and M5a. Myeloid markers detected in ALL were CD13 2.2% and CD33 2.2%. In this study, immunologically classified ALLs were composed of 65.2% of CALLA (+) B precursor type, 10.9% of CALLA (-) B precursor pattern, 8.7% of T cell type, 2.2% of B cell type, 4.5% of mixed lymphoid lineage(B&T), 2.2% of undifferentiated leukemia, and 6.5% of hybrid leukemia. Twelve cases of acute leukemias ware finally diagnosed to be 5 cases of hybrid leukemia, 3 cases of B lineage, 3 case of T lineage and 1 case of mixed lymphoid(B&T) leukemia. In summary, we think the best method for typing acute leukemias is by using a combination of FAB classification and immunophenotying.

• Clinical and Experimental Pediatrics
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• v.46 no.1
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• pp.56-66
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• 2003

Purpose : Human umbilical vein endothelial cells(HUVECs) play an important role in regulating blood flow by releasing vasoactive substances. It has been reported that endothelial impairment and dysfunction might be a primary cause of placental vascular disease, which is manifested clinically as preeclampsia in mother and intrauterine growth restriction in fetus. Furthermore, the frequency of apoptotic changes is increased in umbilical and placental tissues from growth-restricted pregnancies. However, the various mechanisms of umbilical endothelial cell apoptosis have not been broadly proposed. We investigate the effects of amiloride derivatives on apoptotic death of HUVECs and identify their ionic mechanism. Methods : HUVECs were purchased from Clonetics, and cultured on endothelial cell growth medium. MTT assay and flow cytometry were used for assessing cytotoxic effect and confirming the apoptosis. Changes in intracellular ion concentrations were measured with specific fluorescent dyes and fluorescence imaging analysis system. Results : Amiloride derivatives elicited cytotoxic effects on HUVECs with dose-dependent manners and the rank order of potency is HMA($IC_{50}\;11.2{\mu}M$), MIA>EIPA>>amiloride. HMA-induced cytotoxicity is dependent on extra- and intracellular pH, that is, increase extra- and intracellular pH augmented the cytotoxic effects of HMA. HMA dose-dependently reduced intracellular major ions, such as $K^+$ and $Cl^-$. Interestingly, the depletion of intracellular ions induced by HMA was also significantly enhanced at alkaline extracellular pH. Conclusion : Amiloride derivatives induce apoptosis of HUVECs with dose and pH dependent manners. They reduce intracellular $K^+$ and $Cl^-$ concentration, which is also extracellular pH dependent.