• 접착 및 계면
• /
• 제14권1호
• /
• pp.13-20
• /
• 2013

팔라듐은 치과 및 의료용 기구, 의료용 재료, 보석 및 자동차, 고기능성 점 접착제 등을 생산하는데 중요한 역할을 한다. 팔라듐을 이용하는 반응에서의 중요성에도 불구하고 팔라듐은 최종생성물에 잔존할 경우 인체에 해로운 독성을 가지고 있다. 그 중에서도 특히 $PdCl_2$는 독성이 가장 크다. 따라서 $Pd^{2+}$ 이온 검출은 매우 중요한 연구과제인데 그 중에서도 특히 형광분석법은 가장 손쉽고 경제적이면서 감도가 높고 선택성이 높은 방법으로 알려져 있다. 본 연구에서는 알파-카보닐로 치환된 파이렌 유도체인 감마-옥소-1-파이렌부틸산(OPBA)이 수용액에 금속이온으로 감도가 크고 선택성이 우수한 것으로 밝혀졌다.

• Preventive Nutrition and Food Science
• /
• 제8권4호
• /
• pp.390-394
• /
• 2003

In the post-genome period, the technique for identifying gene expression has been progressed to high throughput screening. In the field of molecular nutrition, the use of screening techniques to clarify molecular function of specific nutrients would be very advantageous. In this study, we have evaluated Zn-regulated gene expression in Zn-deficient, homocystein-treated EA.hy926 cells, using cDNA microarray, which can be used to screen the expression of many genes simultaneously. The information obtained can be used for preliminary assessment of molecular and signaling events modulated by Zn under pro-atherogenic conditions. EA.hy926 cells derived from human umbilical vein endothelial cells were cultured in Zn-adequate (control, 15 $\mu$M Zn) or Zn-deficient (experimental, 0 $\mu$M Zn) Dulbecco's MEM media under high homocysteine level (100 $\mu$M) for 3 days of post-confluency. Cells were harvested and RNA was extracted. Total RNA was reverse-transcribed and the synthesized cDNA was labeled with Cy3 or Cy5. Fluorescent labeled cDNA probe was applied to microarray slides for hybridization, and the slide was then scanned using a fluorescence scanner. The expression of seven genes was found to be significantly decreased, and one significantly increased, in response to treatment of EA.hy926 cells with Zn-deficient medium, compared with Zn-supplemented medium. The upregulated genes were oncogenes and tumor suppressor genes, cell cycle-related genes and transporter genes. The down-regulated gene was RelB, a component of the NF-kappaB complex of transcription factors. The results of this study imply the effectiveness of cDNA microarray for expression profiling of a singly nutrient deficiency, namely Zn. Furthur study, using tailored-cDNA array and vascular endothelial cell lines, would be beneficial to clarify the molecular function of Zn in atherosclerosis, more in detail.

• The Korean Journal of Physiology and Pharmacology
• /
• 제20권4호
• /
• pp.347-355
• /
• 2016

Cryptotanshinone (CPT) is a natural compound isolated from traditional Chinese medicine Salvia miltiorrhiza Bunge. In the present study, the regulatory effect and potential mechanisms of CPT on tumor necrosis factor alpha ($TNF-{\alpha}$) induced lectin-like receptor for oxidized low density lipoprotein (LOX-1) were investigated. Human umbilical vein endothelial cells (HUVECs) were cultured and the effect of $TNF-{\alpha}$ on LOX-1 expression at mRNA and protein levels was determined by Real-time PCR and Western blotting respectively. The formation of intracellular ROS was determined with fluorescence probe $CM-DCFH_2-DA$. The endothelial ox-LDL uptake was evaluated with DiI-ox-LDL. The effect of CPT on LOX-1 expression was also evaluated with SD rats. $TNF-{\alpha}$ induced LOX-1 expression in a dose- and time- dependent manner in endothelial cells. $TNF-{\alpha}$ induced ROS formation, phosphorylation of $NF-{\kappa}B$ p65 and ERK, and LOX-1 expression, which were suppressed by rotenone, DPI, NAC, and CPT. $NF-{\kappa}B$ inhibitor BAY11-7082 and ERK inhibitor PD98059 inhibited $TNF-{\alpha}-induced$ LOX-1 expression. CPT and NAC suppressed $TNF-{\alpha}-induced$ LOX-1 expression and phosphorylation of $NF-{\kappa}B$ p65 and ERK in rat aorta. These data suggested that $TNF-{\alpha}$ induced LOX-1 expression via ROS activated $NF-{\kappa}B/ERK$ pathway, which could be inhibited by CPT. This study provides new insights for the anti-atherosclerotic effect of CPT.

• BMB Reports
• /
• 제33권6호
• /
• pp.541-547
• /
• 2000

Fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) was used to evaluate the effects of chlorpromazine HCl on the range of the rotational mobility of bulk bilayer structure of the synaptosomal plasma membrane vesicles (SPMV) isolated from a bovine brain. In a dose-dependent manner, chlorpromazine HCl increased the anisotropy (r), limiting anisotropy ($r_{\infty}$) and order parameter (S) of DPH in the membranes. Cationic 1-[4-(trimethylammonio)-phenyl]-6-phenylhexa-1,3,5-hexatriene (TMA-DPH) and anionic 3-[p-(6-phenyl)-1,3,5-hexatrienyl]-phenylpropionic acid (PRO-DPH) were utilized to examine the range of transbilayer asymmetric rotational mobility of the neuronal membranes. The anisotropy (r) of TMA-DPH in the inner monolayer was 0.034 greater than the value of PRO-DPH in the outer monolayer of the membranes. Both cationic TMA-DPH and anionic PRO-DPH were also used to examine the transbilayer asymmetric effects of chlorpromazine HCl on the range of rotational mobility of the membranes. Chlorpromazine HCl have a decreasing effects on the rotational mobility of the bulk bilayer structures and have a greater decreasing effect on the mobility of the inner monolayer as compared to the outer monolayer of the membranes. It has been proven that chlorpromazine HCl exhibit a selective rather than nonselective fluidizing effect within the transbilayer domains of the SPMV.

• 보존과학회지
• /
• 제6권1호
• /
• pp.3-14
• /
• 1997

15세기 말과 16세기 초에 철화분청을 생산했던 곳으로 잘 알려진 공주 학봉리에서 수습된 12 도편의 분청사기를 과학적으로 분석하였다. 태토와 유약의 성분은 각각 X선 형광분석기와 전자현미분석장치로 분석하였고, 미세구조분석은 광학현미경, 편광현미경, 전자현미분석장치, 그리고 X선회절분석기를 이용하였다. 태토와 유약의 성분은 학봉리에서 지리적으로 가까운 곳에 위치한 보령 용수리분청과 비교하여 통계분석을 하였으며, SPSS프로그램을 사용하였다 태토는 보령 송수리 분청에 비해 실리카와 용융제는 높게 나타났으나, 알루미나는 낮은 수치를 보였고, 유약은 실리카, 소다. 철산화물은 높은 반면, 알루미나와 칼슘산화물의 양은 낮게 나타났다. 학봉리 분청 자체도 두 그룹으로 나뉘었다. 유약은 라임계열이었으며, 태토내에는 석영, 둘레가 일부 녹은 큰 장석덩어리, 사장석, 흑운모와 철산화물과 같은 결정들이 많이 남아있음을 관찰할 수 있었다. 이러한 미세구조로 보아 원료의 수비상태가 좋지 않았고, 번조온도도 비교적 낮았음을 예측할 수 있다. 철화안료의 원료는 성분과 X선 회절분석에 의해 Mg/Fe/Al 스피넬로 확인되었다.

• Environmental Engineering Research
• /
• 제17권4호
• /
• pp.205-210
• /
• 2012

Hydroperoxyl radical/superoxide anion radical ($HO_2{\cdot}/O_2^-{\cdot}$, $pK_a$=4.8) as an intermediate is of considerable importance in oxidation processes. Hence, the method of detecting $HO_2{\cdot}/O_2^-{\cdot}$ with high sensitivity is necessary to be developed. To achieve this objective, this study newly employed terephthalate (TA) as a probe for the measurement of $HO_2{\cdot}/O_2^-{\cdot}$ in the kinetic method presented in our previous study. This method was based on the hydroxylation of TA to produce mainly hydroxyterephthalic acid or hydroxyterephthalate (OHTA), which was analyzed by fluorescence detection (${\lambda}_{ex}$=315nm, ${\lambda}_{ex}$=425nm). The life-time of $HO_2{\cdot}/O_2^-{\cdot}$ and its concentration formed from the photolysis technique of $H_2O_2$ were reported in this study. At range of pH 2-10, the life-time of $HO_2{\cdot}/O_2^-{\cdot}$ was 51-422 sec. In particular, an increase in the life-time with pH was observed. The sensitivities of the kinetic method by using TA were always higher with 1.7-2.5 times at pH 8.0 than those by using benzoic acid. From these results, this study can contribute to understanding the basic functions of $HO_2{\cdot}/O_2^-{\cdot}$ in oxidation processes.

• 원예과학기술지
• /
• 제33권1호
• /
• pp.83-92
• /
• 2015

xBrassicoraphanus line BB#5, a new synthetic intergeneric hybrid between Brassica rapa L. ssp. pekinensis and Raphanus sativus L. var. rafiphera induced by N-methyl-N-nitroso-urethane mutagenesis in microspore culture, shows high seed fertility and morphological uniformity. Dual-color fluorescence in situ hybridization (FISH) using 5S and 45S rDNA probes and genomic in situ hybridization (GISH) using B. rapa genomic DNA probe were carried out to analyze the chromosome composition and the meiosis pairing pattern compared to its parental lines. The somatic chromosome complement is 2n = 38, which consists of 17 metacentric and two submetacentric chromosomes with lengths of 2.18 to $5.01{\mu}m$. FISH karyotype analysis showed five and eight pairs of 5S and 45S rDNA loci. GISH meiosis pairing analysis showed that 19 complete bivalents were most frequent and accounted for 42% of the 100 pollen mother cells examined. Based on chromosome number, size, morphology, rDNA distribution, and meiosis pairing pattern, both parental genomes of B. rapa and R. sativus appear to exist in xBrassicoraphanus line BB#5, demonstrating its genome integrity. Such stable chromosome constitutions and meiotic pairing patterns in somatic and meiotic cells are very rare in natural and synthetic intergeneric hybrids. Chromosomal studies and genetic and phenotypic changes in allopolyploids a re discussed. The results p resented h erein will b e usef ul f or f urther g enomic s tudy o f xBrassicoraphanus lines and their improvement as promising new breeding varieties.

• Bulletin of the Korean Chemical Society
• /
• 제22권5호
• /
• pp.467-475
• /
• 2001

A triblock copolymer based on $poly(\varepsilon-caprolactone)$ (PCL) as the hydrophobic part and poly(ethylene glycol) (PEG) as the hydrophilic portion was synthesized by a ring-opening mechanism of ${\varepsilon}-caprolactone$ with PEG containing a hydroxyl group at bot h ends as an initiator. The synthesized block copolymers of PCL/PEG/PCL (CEC) were confirmed and characterized using various analysis equipment such as 1H NMR, DSC, FT-IR, and WAXD. Core-shell type nanoparticles of CEC triblock copolymers were prepared using a dialysis technique to estimate their potential as a colloidal drug carrier using a hydrophobic drug. From the results of particle size analysis and transmission electron microscopy, the particle size of CEC core-shell type nanoparticles was determined to be about 20-60 nm with a spherical shape. Since CEC block copolymer nanoparticles have a core-shell type micellar structure and small particle size similar to polymeric micelles, CEC block copolymer can self-associate at certain concentrations and the critical association concentration (CAC) was able to be determined by fluorescence probe techniques. The CAC values of the CEC block copolymers were dependent on the PCL block length. In addition, drug loading contents were dependent on the PCL block length: the larger the PCL block length, the higher the drug loading content. Drug release from CEC core-shell type nanoparticles showed an initial burst release for the first 12 hrs followed by pseudo-zero order release kinetics for 2 or 3 days. CEC-2 block copolymer core-shell type nanoparticles were degraded very slowly, suggesting that the drug release kinetics were governed by a diffusion mechanism rather than a degradation mechanism irrelevant to the CEC block copolymer composition.

• Experimental Neurobiology
• /
• 제26권5호
• /
• pp.241-251
• /
• 2017

Saturation mutagenesis was performed on a single position in the voltage-sensing domain (VSD) of a genetically encoded voltage indicator (GEVI). The VSD consists of four transmembrane helixes designated S1-S4. The V220 position located near the plasma membrane/extracellular interface had previously been shown to affect the voltage range of the optical signal. Introduction of polar amino acids at this position reduced the voltage-dependent optical signal of the GEVI. Negatively charged amino acids slightly reduced the optical signal by 33 percent while positively charge amino acids at this position reduced the optical signal by 80%. Surprisingly, the range of V220D was similar to that of V220K with shifted optical responses towards negative potentials. In contrast, the V220E mutant mirrored the responses of the V220R mutation suggesting that the length of the side chain plays in role in determining the voltage range of the GEVI. Charged mutations at the 219 position all behaved similarly slightly shifting the optical response to more negative potentials. Charged mutations to the 221 position behaved erratically suggesting interactions with the plasma membrane and/or other amino acids in the VSD. Introduction of bulky amino acids at the V220 position increased the range of the optical response to include hyperpolarizing signals. Combining The V220W mutant with the R217Q mutation resulted in a probe that reduced the depolarizing signal and enhanced the hyperpolarizing signal which may lead to GEVIs that only report neuronal inhibition.

• Journal of Gastric Cancer
• /
• 제19권2호
• /
• pp.157-164
• /
• 2019

Purpose: Although standard radical gastrectomy is recommended after noncurative resection of endoscopic submucosal dissection (ESD) for early gastric cancer in most cases, residual tumor and lymph node metastasis have not been identified after surgery. The aim of this study is to evaluate the feasibility of sentinel node navigation surgery after noncurative ESD. Materials and Methods: This trial is an investigator-initiated, multicenter prospective phase II trial. Patients who underwent ESD for clinical stage T1N0M0 gastric cancer with noncurative resections were eligible. Qualified investigators who completed the prior phase III trial (SENORITA 1) are exclusively allowed to participate. In this study, 2 detection methods will be used: 1) intraoperative endoscopic submucosal injection of dual tracer, including radioisotope and indocyanine green (ICG) with sentinel basins detected using gamma-probe; 2) endoscopic injection of ICG, with sentinel basins detected using a fluorescence imaging system. Standard laparoscopic gastrectomy with lymphadenectomy will be performed. Sample size is calculated based on the inferior confidence interval of the detection rate of 95%, and the calculated accrual is 237 patients. The primary endpoint is detection rate, and the secondary endpoints are sensitivity and postoperative complications. Conclusions: This study is expected to clarify the feasibility of laparoscopic sentinel basin dissection after noncurative ESD. If the feasibility is demonstrated, a multicenter phase III trial will be initiated to compare laparoscopic sentinel node navigation surgery versus laparoscopic standard gastrectomy in early gastric cancer after endoscopic resection.