• Annals of Clinical Neurophysiology
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• 제16권1호
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• pp.1-7
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• 2014

Iron is an important element for brain oxygen transport, myelination, DNA synthesis and neurotransmission. However, excessive iron can generate reactive oxygen species and contribute neurotoxicity. Although brain iron deposition is the natural process with normal aging, excessive iron accumulation is also observed in various neurological disorders such as neurodegeneration with brain iron accumulation, Parkinson's disease, Alzheimer's disease, multiple sclerosis, Friedreich ataxia, and others. Magnetic resonance image (MRI) is a useful method for detecting iron deposits in the brain. It can be a powerful tool for diagnosis and monitoring, while furthering our understanding of the role of iron in the pathophysiology of a disease. In this review, we will introduce the mechanism of iron toxicity and the basics of several iron-related MRI techniques. Also, we will summarize the previous results concerning the clinical application of such MR imagings in various neurological disorders.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권6호
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• pp.516-521
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• 2006

The use of gltA gene, as a new biomarker for environmental stress biomonitoring, was investigated because of its key position as the first enzyme of the tricarboxylic acid (TCA) cycle. A recombinant bioluminescent Escherichia coli strain, EBJM2, was constructed using a plasmid carrying the citrate synthase (gltA) promoter transcribing the Photorhabdus luminescens IuxCDABE genes (gltA::luxCDABE). The responses from this strain were studied with five different classes of toxicants: DNA damage chemicals, phenolics, oxidative-stress chemicals, PAHs, and organic solvents. EBJM2 responded strongly to DNA damage chemicals, such as mitomycin C (MMC) and methyl-nitro-nitrosoguanidine (MNNG) and nalidixic acid with the strongest responses. In contrast, tests with several compounds from the other four classes of toxicants gave no significant response. Therefore, EBJM2 was found to be sensitive to DNA damage chemicals.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 추계학술대회
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• pp.133-133
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• 2003

In recent years. attention has focused on the application of the alkaline single cell gel electrophoresis (SCGE or Comet) assay in environmental mutagenesis. To evaluate the suitability of the assay as a monitoring. technique, the DNA damages in liver cells and erythrocytes of carp (Cyprinus carpio) exposed to benzo[${\alpha}$]pyrene (B[${\alpha}$]P) were estimated comparatively with the in vivo Comet assay and the micronucleus test (MNT).(omitted)

• 대한임상독성학회지
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• 제19권1호
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• pp.51-54
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• 2021

Chlorfenapyr is a widely used insecticide, that is very lethal if ingested. It exhibits delayed toxicity in which there are few symptoms at first which suddenly worsen after a few days. A 66-year-old female patient ingested about 90 mL of chlorfenapyr liquid hydrating agent (Chlofenapyr 10%) and showed stable vital signs with no specific symptoms and findings other than a mild fever, vomiting, and nausea. From the 3rd day of ingestion, creatine kinase was high, and rhabdomyolysis was suspected. From the 4th day of ingestion, pancreatic enzymes began to gradually increase. A diffusion-weighted image showed a multifocal high signal intensity in the white matter and corpus callosum area. On the 8th day after ingestion, she suffered a high fever and a heart attack and died. Thus, if a patient is suspected of taking chlorfenapyr, he/she needs active treatment and monitoring even if he/she does not exhibit any symptoms.

• 분석과학
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• 제35권2호
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• pp.82-91
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• 2022

Grayanotoxin-contaminated honey exhibits toxicity. In this study, a reliable and sensitive liquid-chromatography-tandem-mass-spectrometric method (LC-MS/MS) was developed and validated for the quantitation of grayanotoxin I and grayanotoxin III in honey. The grayanotoxins were extracted from honey via solid phase extraction and separated on a biphenyl column with a mobile phase consisting of 0.5 % acetic acid in water and methanol. Mass spectrometric detection was performed in the multiple-reaction monitoring mode with positive electrospray ionization. The calibration curve covered the range 0.25 to 100 ㎍/g. The intra- and inter-day deviations were less than 10.6 %, and the accuracy was between 94.3 and 114.0 %. The validated method was successfully applied to the determination of grayanotoxins in mad honey from Nepal. The concentrations of grayanotoxin I and grayanotoxin III in 33 out of 60 mad honey samples were 0.75 - 64.86 ㎍/g and 0.25 - 63.99 ㎍/g, respectively. The method established herein would help in preventing and confirming grayanotoxin poisoning.

• 도시과학
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• 제12권2호
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• pp.7-12
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• 2023

The purpose of this study is to explore the issue of antibiotic misuse and the associated environmental problems, focusing on the antibiotic sulfamethoxazole used in animal agriculture. Antibiotic resistance is currently a global problem, exacerbated by the misuse of antibiotics in agriculture and animal husbandry. This study emphasizes the importance of investigating the potential environmental toxicity of antibiotics and discovering efficient treatment technologies. It discusses the use of advanced oxidation processes and artificial wetlands as potential approaches to mitigate the environmental impact of antibiotics, particularly sulfamethoxazole. In conclusion, the study underscores the need for research, data collection, monitoring, and effective environmental protection policies to combat antibiotic misuse and environmental pollution. It also emphasizes the significance of raising awareness and implementing proactive measures to address these issues.

• 한국진공학회지
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• 제19권6호
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• pp.442-452
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• 2010

본 연구의 목적은 나노기술에 대한 일반인의 인식과 참여를 제고하기 위해 '소비자 모니터링'이라는 대중참여모델을 고안하고 그 실행결과를 검토하는데 있다. 모니터 요원은 서울과 부산 지역에 거주하는 30~40대 여성 22명이었다. 이들은 모두 대학 시절 이공계를 전공했기 때문에 과학기술에 대한 일반 지식을 갖추고 있었다. 모니터 대상은 일상생활에 사용되는 나노제품 167개였고, 모니터 기간은 약 1개월이었다. 주요 결과는 다음과 같다. 제품에 '나노'라는 용어의 정의와 나노물질의 크기를 적시한 수는 2개(1.2%)였다. 제품에 적용된 나노기술의 내용을 충분히 설명한 수는 15개(9/0%)였다. 제품의 기능이 향상된 이유를 충분히 설명한 수는 14개(8.4%)였으며, 과장이나 잘못된 지식이 표현됐다고 의심되는 수는 27개(16.2%)였다. 또한 인체와 환경에 대한 위해 가능성이 의심되는 수가 88개(52.7%)였으며, 안전성과 관련한 설명을 명시해야 한다고 지적된 수는 84개(50.3%)였다. 모니터 요원들은 이번 경험을 토대로, 정부가 나노제품의 안전성을 입증해주는 인증제도를 조속히 도입할 것을 촉구했으며, 기업이 나노제품의 설명서에 상세하고 신뢰감 있는 내용을 담을 것을 요구했다.

• 한국환경과학회지
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• 제24권5호
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• pp.623-631
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• 2015

Microarray technology provides a unique tool for the determination of gene expression at the level of messenger RNA (mRNA). This study, the mRNA expression profiles provide insight into the mechanism of action of cadmium in Fleshy shrimp (Fenneropenaeus chinensis). The ability of genomic technologies was contributed decisively to development of new molecular biomarkers and to the determination of new possible gene targets. Also, it can be approach for monitoring of trace metal using oligo-chip microarray-based in potential model marine user level organisms. 15K oligo-chip for F. chinensis that include mostly unique sets of genes from cDNA sequences was developed. A total of 13,971 spots (1,181 mRNAs up- regulated and 996 down regulated) were identified to be significantly expressed on microarray by hierarchical clustering of genes after exposure to cadmium for different conditions (Cd24-5000 and Cd48-1000). Most of the changes of mRNA expression were observed at the long time and low concentration exposure of Cd48-1000. But, gene ontology analysis (GO annotation) were no significant different between experiments groups. It was observed that mRNA expression of main genes involved in metabolism, cell component, molecular binding and catalytic function. It was suggested that cadmium inhibited metabolism and growth of F. chinensis.

• Environmental Analysis Health and Toxicology
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• 제18권2호
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• pp.145-153
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• 2003

The goal of this study is to develop a biomarker used in monitoring abnormal behaviors of Japanese medaka (Oryzias latipes) as a model organism caused by hazardous chemicals. Japanese medaka was treated by copper of appropriate sublethal concentrations after starvation for 48 hr. The untreated individuals showed common behavioral characteristics (i.e. , smooth and linear movements). Locomotive activity of the fish was monitored using an image processing and automatic data acquisition system. When treated with copper (100 ppb), the fish showed shaking patterns more frequently. As the concentration of copper increased to 1,000 ppb, activity decreated, and the fish showed an erratic movement. Fish were exposed to copper at various concentrations (0,100 and 1,000 ppb) for 24 hrs, and acetylcholine esterase (AChE) activity was observed. When fish were exposed to 1,000 ppb of copper, the body AChE activities appeared to decrease but the head AChE activities showed little change. Expressions of tyrosine hydroxylase (TH) protein in the different organs from both head (brain) and body (kidney) portions affected by the copper treatment were analyzed using immunohistochemical technique compared with control. Five organs of the fish (olfactory bulb, hyothalamus, optic lobe, pons and myelencephalon regions) showed a relatively strong TH protein expression in the control experiment. A differential expression of TH, however, was observed in the treatment (100 ppb and 1,000 ppb). The treatment (1,000 ppb) significantly suppressed TH protein production in the brain regions. In kidney, however, the same treatment caused little suppression compared with the control. Copper appeared to be less effective in suppression of TH than diazinon, a known TH suppressor. It was concluded that TH could be used at a potential biomarker to monitor the acute copper toxicity in Japanese medaka.

• 한국가축번식학회지
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• 제21권2호
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• pp.123-130
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• 1997

Normal maturation of the mammalian oocytes is prerequisite for the fertilization and the early embryonic development. We have been tested the effects of purine and its de novo synthetic inhibitor, azaserine(Aza) on the maturation of germinal vesicle(GV) and germinal vesicle breakdown(GVBD) mouse oocytes. Denude-immature oocytes were cultivated in the media containing adenosine, guanosine, and/or azaserine, and checked the matruation stage by monitoring the prominent morphological changes. In GV stage oocytes, GV was arrested temporarily by the adenosine(1.0%) and protractedly by the guanosine(65.9%, P<0.001). The regression was increased significantly at the adenosine(90%, P<0.001) but decreased at the guanosine(1.6%, P<0.05). Inhibiting the de novo synthesis of purine, nuclear maturation rate was increase(90.4% : 96.7%), but GV arrest was significantly increased by cotreatment with guanosine(P<0.001). Polar body extraction significantly was increased at the Aza(P<0.05), but not in others. In GVBD oocytes, adenosine itself did not affect GVBD arrest. Guanosine, on the other hand, elevated GVBD arrest rate(P<0.001), but co-treated with Aza, decreased GVBD arrest(P<0.001). Aza increased GVBD arrest rate(20.2%, P<0.05) compared with control. From those results, we know that guanosine shows more prominent effect on the inhibition of nuclear maturation at the GV stage, and of the 1st polar body extrusion at the GVBD stage. Adenosine showed the cytoplasmic toxicity at GV stage oocyte. Our data speculate that cytoplasmic cAMP level is auto-regulated by endogenous adenylate cyclase while GVBD is inhibited by guanosine, since purine toxicity is not observed in the GVBD stage. And it is showed that purine metabolism is concerned with nuclear maturation, that the amounts of purine metabolism is not even during the oocyte maturation.