• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
• /
• pp.461-461
• /
• 2013

Over the last decade, zinc oxide (ZnO) thin films have attracted considerable attention owing to large band gap of 3.37 eV and large exciton binding energy of 60 meV at room temperature [1-3]. Recent interest in ZnO related researches has been switched into the fabrication and characterization of low-dimensional nanostructures, such as nano-wires and nano-dots that can be applicable to manufacture the optoelectronic devices such as ultraviolet lasers, light-emitting-diodes and detectors. Since the optical properties of ZnO nano-structures might be distinct from those of bulk materials or thin films, the low-dimensional phenomena should be examined further. In order to utilize such advanced optoelectronic devices, one of the challenges is how to control the surface state related emissions that are drastically increased with increasing the density of the nano-structures and the surface-to-volume ratio. This paper reports the synthesis and characterization of self-assembled ZnO hexagonal nano-disks grown by radio-frequency magnetron sputtering. X-ray diffraction data and scanning electron microscopy data showed that ZnO hexagonal nano-disks were nucleated on top of the flat surfaces as the film thickness reached to 1.56 ${\mu}m$ and then the number of nano-disks increased with increasing the film thickness. The lateral size of hexagonal nano-disks was ~720 nm and height was ~74 nm. The strong photo luminescence spectra obtained at 10 K was also observed, which was assigned to a surface exciton emission at 3.3628 eV arising from the surface sites of hexagonal nano-disks.

• 대한화장품학회:학술대회논문집
• /
• 대한화장품학회 1999년도 IFSCC . ASCS 학술대회 발표 논문
• /
• pp.1-5
• /
• 1999

The purpose of this study was to determine the effect of IPBC(3-lodo-2-propynylbutyl carbamate) on dandruff caused by the anthropophilic fungus Maiassezia furfur. The effects of IPBC on dandruff were examined by evaluating (a) the MIC value of IPBC using broth dilution method : (b) the remnant antimicrobial activity of IPBC containing shampoo on skin disc ; (c) the antidandruff efficacy of 1.0 % IPBC containing shampoo in double blind clinical trial. To investigate the remnant antimicrobial activity of IPBC against Maiassezia furfur, guinea pig-skin disc was washed with antidandruff shampoo and then the diameter of inhibition zone per disc was measured. For clinical trial, thirty healthy volunteers, aged 25-35, participated in 4 week study. At 0,2,4 weeks, examinations of scaling, itching on scalp were carried out. The MIC(Minimun Inhibition Concentration) values of IPBC range from 0.10 to 1.00$\mu$ g/ml and it seems that IPBC is more effective in the MIC values than zinc pyrithione, selenium disulphide, piroctone olamine and comparable to ketoconazole, climbazole. When the rimnant antimicrobial activity of IPBC shampoo on skin disc was determined, 0.5% IPBC shampoo and 2.0% Ketoconazole shampoo resulted in similar antimicrobial effect. In addition, 1.0%,2.0% IPBC shampoo was more effective than 2.0% ketoconazole shampoo. After two and four-weeks of 1.0% IPBC shampoo treatment, there was significant reduction of scaling, itching in test group compared to control group. On the basis of these results, it can be concluded that 1.0% IPBC is more effective than 2.0% Ketoconazole in reducing dandruff. It seems that strong capacity of drug binding to the stratum corneum plays a role in its antidandruff effect since adsorption of active ingredients on scalp is very important factor in reducing dandruff.

• 한국재료학회:학술대회논문집
• /
• 한국재료학회 2009년도 춘계학술발표대회
• /
• pp.24.1-24.1
• /
• 2009

The zinc oxide (ZnO) material as the II-VI compound semiconductor is useful in various fields of device applications such as light-emitting diodes (LEDs), solar cells and gas sensors due to its wide direct band gap of 3.37eV and high exciton binding energy of 60meV at room temperature. In this study, the ZnO nanorods were deposited onto homogenous buffer layer/Si(100) substrates by a hydrothermal synthesis. The Effects of the buffer layer annealing and post annealing temperature on the structural and optical properties of ZnO nanorods grown by a hydrothermal synthesis were investigated. For the buffer layer annealing case, the annealed buffer layer surface became rougher with increasing of annealing temperature up to $750^{\circ}C$, while it was smoothed with more increasing of annealing temperature due to the evaporation of buffer layer. It was found that the roughest surface of buffer layer improved the structural and optical properties of ZnO nanorods. For the post annealing case, the hydrothermally grown ZnO nanorods were annealed with various temperatures ranging from 450 to $900^{\circ}C$. Similarly in the buffer layer annealing case, the post annealing enhanced the properties of ZnO nanorods with increasing of annealing temperature up to $750^{\circ}C$. However, it was degraded with further increasing of annealing temperature due to the violent movement of atoms and evaporation. Finally, the buffer layer annealing and post annealing treatment could efficiently improve the properties of hydrothermally grown ZnO nanorods. The morphology and structural properties of ZnO nanorods grown by the hydrothermal synthesis were measured by atomic force microscopy (AFM), field emission scanning electron microscopy (SEM), and x-ray diffraction (XRD). The optical properties were also analyzed by photoluminescence (PL) measurement.

• Molecules and Cells
• /
• 제41권7호
• /
• pp.695-702
• /
• 2018

The inner ear is a complex sensory organ responsible for hearing and balance. Formation of the inner ear is dependent on tight regulation of spatial and temporal expression of genes that direct a series of developmental processes. Recently, epigenetic regulation has emerged as a crucial regulator of the development of various organs. However, what roles higher-order chromatin organization and its regulator molecules play in inner ear development are unclear. CCCTC-binding factor (CTCF) is a highly conserved 11-zinc finger protein that regulates the three-dimensional architecture of chromatin, and is involved in various gene regulation processes. To delineate the role of CTCF in inner ear development, the present study investigated inner ear-specific Ctcf knockout mouse embryos (Pax2-Cre; $Ctcf^{fl/fl}$). The loss of Ctcf resulted in multiple defects of inner ear development and severely compromised otic neurogenesis, which was partly due to a loss of Neurog1 expression. Furthermore, reduced Neurog1 gene expression by CTCF knockdown was found to be associated with changes in histone modification at the gene's promoter, as well as its upstream enhancer. The results of the present study demonstrate that CTCF plays an essential role in otic neurogenesis by modulating histone modification in the Neurog1 locus.

• 한국환경농학회지
• /
• 제16권4호
• /
• pp.311-319
• /
• 1997

광산폐수, 산업폐수등으로 부터 Cd, Pb, Zn 및 Cu등의 중금속에 강한 내성을 지니고 있을 뿐만 아니라 균체내 중금속 축적능력이 우수한 중금속 내성 미생물 균주 Pseudomonas putida(Cd), Pseudomonas aeruginosa(Pb), Pseudomonas chlororaphis(Zn) 및 Pseudomonas stutzeri(Cu)를 각각 분리하여, 여러가지 물리화학적인 방법으로 세포를 전처리하여 세포구성성분을 인위적으로 조절한 후 세포내 중금속이온의 흡수 거동 및 조단백질 함량과 중금속 축적관계를 조사한 결과는 다음과 같다. 세포를 알카리로 전처리하였을 경우 세포내 중금속 축적은 매우 감소되었으며, 메탄올과 클로포름으로 전처리하였을 경우에는 중금속 축적에 큰 영향을 미치지 않았으나, 메탄올과 클로로포름으로 전처리한 후 다시 알카리로 재차 처리하였을 경우에는 중금속 축적이 매우 감소되었다. 전처리된 세포내 중금속 축적은 용출되지 않고 남아있는 조단백질 함량이 감소됨에 따라 더 얼마나 크게 감소되었으므로 세포 구성물질중 단백질이 중금속 축적에 중요한 역할을 하는 물질인 것으로 판단되었다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2009년도 제38회 동계학술대회 초록집
• /
• pp.101-101
• /
• 2010

ZnO shows a direct band gap of 3.37eV, large exciton binding energy (~60 meV), high oxidation ability, high sensitivity to many gases, and low cost, and it has been used in various applications such as transparent electrodes, light emitting diodes (LEDs), gas sensors and photocatalysts. Among these applications ZnO as photocatalyst has considerably attracted attention over the past few years because of its high activities in removing organic contaminants generated from industrial activities. In this research, ZnO nanoparticles were synthesized by spray-pyrolysis method using the zinc acetate dihydrate as starting material at synthesis temperature of $900^{\circ}C$ with concentration varied from 0.01 to 1.0M. The physical and chemical properties of the synthesized ZnO nanoparticles were examined by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transformation Infrared (FT-IR), and UV-vis spectroscopy. The Miller indices of XRD patterns indicate that the synthesized ZnO nanoparticles showed a hexagonal wurtzite structure. With increased precursor concentration, a primary, secondary particle sizes of ZnO nanoparticles increased by 0.8 to $1.5{\mu}m$ and 15 to 35nm, and their crystallinity was improved. Methyleneblue (MB) solution ($1{\mu}M$) as a test comtaminant was prepared for evaluating the photocatalytic activities of ZnO nanoparticles synthesized in different precursor concentration. The results show that the photocatalytic efficiency of ZnO nanoparticles was gradually enhanced by increased precursor concentration.

• Toxicological Research
• /
• 제21권3호
• /
• pp.209-218
• /
• 2005

We investigated effects of recombinant human erythropoietin (rHuEPO) on profiles of mRNA transcripts in 6 male cynomolgus (M. fascicularis) monkey's spleen for 4 weeks. Six monkeys, composed of control and treatment group (Control : M1, M2, M3: Treatment : M4, M5, M6) were intravenously administered 3 times per week without or with a dose of rHuEPO 2730 IU/0.1 ml/kg. After 4 weeks rHuEPO treatment, spleen was removed for RNA isolation. Splenic gene expression was assessed using Affymetrix U133A 2.0 arrays containing 18,400 transcripts and variants, including 14,500 well-characterized human genes. Gene expression pattern was very different between individuals even in same treatment. In rHuEPO treated groups showed number of genes were up- or down-regulated (M4: 79: M5: 48; M6: 73 genes). Six genes (epidermal growth factor receptor, calgranulin A, estrogen receptor binding site associated antigen, matrix metalloproteinase 19, zinc finger and BTB domain containing 16, progestin and adipoQ receptor) were commonly expressed in rHuEPO treated group. The different individual response could be major considering factor in monkey experiment. Further study is needed to clarify the different individual response to rHuEPO in molecular level. This study will be valuable in the fundamental understanding and validation of molecular toxicology for bio-generic drugs including rHuEPO in cynomolgus monkey.

• Journal of Genetic Medicine
• /
• 제11권2호
• /
• pp.79-82
• /
• 2014

Mowat-Wilson syndrome is an extremely rare genetic disease that is characterized by intellectual disability, facial dysmorphism, Hirschsprung's disease, and other congenital anomalies. This disorder is caused by heterozygous mutations or deletions in the zinc finger E-box-binding homeobox-2 gene (ZEB2). Thus far, approximately 200 cases of Mowat-Wilson syndrome have been reported worldwide. In Korea, only one case with a 2q22 deletion, which also affects ZEB2, has been previously reported. Here, we describe a patient with Mowat-Wilson syndrome who presented with developmental delays, typical facial dysmorphism, and Hirschsprung's disease. Molecular analysis of ZEB2 identified a novel heterozygous mutation at c.190dup ($p.S64Kfs^*6$). To our knowledge, this is the second report of a Korean patient with Mowat-Wilson syndrome that has been confirmed genetically.

• BMB Reports
• /
• 제54권6호
• /
• pp.317-322
• /
• 2021

CCCTC-binding factor (CTCF), a zinc finger protein, is a transcription factor and regulator of chromatin structure. Forebrain excitatory neuron-specific CTCF deficiency contributes to inflammation via enhanced transcription of inflammation-related genes in the cortex and hippocampus. However, little is known about the long-term effect of CTCF deficiency on postnatal neurons, astrocytes, or microglia in the hippocampus of adult mice. To address this, we knocked out the Ctcf gene in forebrain glutamatergic neurons (Ctcf cKO) by crossing Ctcf-floxed mice with Camk2a-Cre mice and examined the hippocampi of 7.5-10-month-old male mice using immunofluorescence microscopy. We found obvious neuronal cell death and reactive gliosis in the hippocampal cornu ammonis (CA)1 in 7.5-10-month-old cKO mice. Prominent rod-shaped microglia that participate in immune surveillance were observed in the stratum pyramidale and radiatum layer, indicating a potential increase in inflammatory mediators released by hippocampal neurons. Although neuronal loss was not observed in CA3, and dentate gyrus (DG) CTCF depletion induced a significant increase in the number of microglia in the stratum oriens of CA3 and reactive microgliosis and astrogliosis in the molecular layer and hilus of the DG in 7.5-10-month-old cKO mice. These results suggest that long-term Ctcf deletion from forebrain excitatory neurons may contribute to reactive gliosis induced by neuronal damage and consequent neuronal loss in the hippocampal CA1, DG, and CA3 in sequence over 7 months of age.

• Journal of Veterinary Science
• /
• 제21권6호
• /
• pp.73.1-73.10
• /
• 2020

Background: Bovine papilloma is a neoplastic disease caused by bovine papillomaviruses (BPVs), which were recently divided into 5 genera and at least 24 genotypes. Objectives: The complete genome sequence of BPV type 15 (BPV Aks-02), a novel putative BPV type from skin samples from infected cows in Southern Xinjiang China, was determined by collecting warty lesions, followed by DNA extraction and amplicon sequencing. Methods: DNA was analyzed initially by polymerase chain reaction (PCR) using the degenerate primers FAP59 and FAP64. The complete genome sequences of the BPV Aks-02 were amplified by PCR using the amplification primers and sequencing primers. Sequence analysis and phylogenetic analysis were performed using bio-informatic software. Results: The nucleotide sequence of the L1 open reading frame (ORF) of BPV Aks-02 was 75% identity to the L1 ORF of BPV-9 reference strain from GenBank. The complete genome consisted of 7,189 base pairs (G + C content of 42.50%) that encoded 5 early (E8, E7, E1, E2, and E4) and 2 late (L1 and L2) genes. The E7 protein contained a consensus CX₂CX₂₉CX₂C zinc-binding domain and a LxCxE motif. Among the different members of this group, the percentages of the complete genome and ORFs (including 5 early and 2 late ORFs) sequence identity of BPV Aks-02 were closer to the genus Xipapillomavirus 1 of the Xipapillomavirus genus. Phylogenetic analysis and sequence similarities based on the L1 ORF of BPV Aks-02 revealed the same cluster. Conclusions: The results suggest that BPV type (BPV Aks-02) clustered with members of the Xipapillomavirus genus as BPV 15 and were closely related to Xipapillomavirus 1.