• Journal of Ginseng Research
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• 제33권1호
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• pp.48-54
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• 2009

Epileptifrom discharges were induced in the telencephalon of the adult zebrafish via perfusion with pentylenetetrazole (PTZ), bicuculline methiodide, kainic acid-treated artificial cerebrospinal fluid (aCSF), and $Mg^{2+}$-free aCSF. Ginseng total saponin [GTS ($50{\mu}g/ml$)] was shown to attenuate the occurrence rate of epilpetiform discharges by 50-75%, compared to the control. Ginsenoside $Rg_1$ ($130{\mu}M$) reduced the epileptiform discharges in the isolated telencephalon and delayed the occurrence of behavioral seizures observed from the adult zebrafish placed in the PTZ (10 mM)-containing aquarium water. However, Re was not effective in the suppression of epileptiform discharges and behavioral seizures. These results indicate that $Rg_1$ may be useful in the control of epileptiform discharges and effective in controlling behavioral seizures, and that the zebrafish can be used as a model animal for the testing of potential anticonvulsant drugs.

• 한국발생생물학회지:발생과생식
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• 제23권4호
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• pp.385-390
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• 2019

Upon gene inactivation in animal models, the zebrafish (Danio rerio) has become a useful model organism for many reasons, including the fact that it is amenable to various forms of genetic manipulation. Genome editing is a type of genetic engineering in which DNA is inserted, deleted, modified, or replaced in the genome of a living organism. Mainly, CRISPR (clustered regularly interspaced short palindromic repeats) Cas9 (CRISPR-associated protein 9) is a technology that enables geneticists to edit parts of the genome. In this study, we utilized this technology to generate an mmp15b mutant by using zebrafish as an animal model. MMP15 is the membrane-type MMP (MT-MMP) which is a recently identified matrix metalloproteinase (MMP) capable of degrading all kinds of extracellular matrix proteins as well as numerous bioactive molecules. Although the newly-established mmp15b zebrafish mutant didn't exhibit morphological phenotypes in the developing embryos, it might be further utilized to understand the role of MMP15 in liver-related diseases, such as liver fibrosis, and associated pathogeneses in humans.

• Molecules and Cells
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• 제39권10호
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• pp.750-755
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• 2016

Although innate color preference of motile organisms may provide clues to behavioral biases, it has remained a longstanding question. In this study, we investigated innate color preference of zebrafish larvae. A cross maze with different color sleeves around each arm was used for the color preference test (R; red, G; green, B; blue, Y; yellow). The findings showed that 5 dpf zebrafish larvae preferred blue over other colors (B > R > G > Y). To study innate color recognition further, tyrosinase mutants were generated using CRISPR/Cas9 system. As a model for oculocutaneous albinism (OCA) and color vision impairment, tyrosinase mutants demonstrated diminished color sensation, indicated mainly by hypopigmentation of the retinal pigment epithelium (RPE). Due to its relative simplicity and ease, color preference screening using zebrafish larvae is suitable for high-throughput screening applications. This system may potentially be applied to the analysis of drug effects on larval behavior or the detection of sensory deficits in neurological disorder models, such as autism-related disorders, using mutant larvae generated by the CRISPR/Cas9 technique.

• Molecules and Cells
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• 제38권11호
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• pp.975-981
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• 2015

Precise 3D spatial mapping of cells and their connections within living tissues is required to fully understand developmental processes and neural activities. Zebrafish embryos are relatively small and optically transparent, making them the vertebrate model of choice for live in vivo imaging. However, embryonic brains cannot be imaged in their entirety by confocal or two-photon microscopy due to limitations in optical range and scanning speed. Here, we use light-sheet fluorescence microscopy to overcome these limitations and image the entire head of live transgenic zebrafish embryos. We simultaneously imaged cranial neurons and blood vessels during embryogenesis, generating comprehensive 3D maps that provide insight into the coordinated morphogenesis of the nervous system and vasculature during early development. In addition, blood cells circulating through the entire head, vagal and cardiac vasculature were also visualized at high resolution in a 3D movie. These data provide the foundation for the construction of a complete 4D atlas of zebrafish embryogenesis and neural activity.

• Molecules and Cells
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• 제37권3호
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• pp.270-274
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• 2014

Lymphatic vessels are essential to regulate interstitial fluid homeostasis and diverse immune responses. A number of crucial factors, such as VEGFC, SOX18, PROX1, FOX2C, and GJC2, have been implicated in differentiation and/or maintenance of lymphatic endothelial cells (LECs). In humans, dysregulation of these genes is known to cause lymphedema, a debilitating condition which adversely impacts the quality of life of affected individuals. However, there are no currently available pharmacological treatments for lymphedema, necessitating identification of additional factors modulating lymphatic development and function which can be targeted for therapy. In this report, we investigate the function of genes associated with Bone Morphogenetic Protein (BMP) signaling in lymphatic development using zebrafish embryos. The knock-down of BMP type II receptors, Bmpr2a and Bmpr2b, and type I receptors, Alk3 and Alk3b, as well as SMAD5, an essential cellular mediator of BMP signaling, led to distinct lymphatic defects in developing zebrafish. Therefore, it appears that each constituent of the BMP signaling pathway may have a unique function during lymphatic development. Taken together, our data demonstrate that BMP signaling is essential for normal lymphatic vessel development in zebrafish.

• Animal cells and systems
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• 제15권2호
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• pp.115-121
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• 2011

Previous studies have demonstrated that N-methyl-D-aspartate (NMDA) receptors and acetylcholine receptors are related to learning and memory in rat and mice. In this study, we examined the effects of MK-801, a non-competitive NMDA receptor antagonist, on learning and memory in zebrafish using a passive avoidance test. We further tested whether or not nicotine, a nicotinic acetylcholine receptor agonist, and physostigmine, an acetylcholinesterase inhibitor, reverse the effects of MK-801. Crossing time was increased significantly in the training and test sessions for the controls. When 20 ${\mu}M$ MK-801 was administered prior to the training session, the crossing time did not increase in either session. The MK-801-induced learning deficit was rescued by pretreatment with 20 ${\mu}M$ physostigmine, and crossing time was increased in the training and test sessions compared to the MK-801-treated zebrafish. Further, the MK-801-induced learning deficit was prevented by pretreatment with 20 ${\mu}M$ nicotine, and crossing time was increased in the training session but not in the test session. These results show that MK-801 induced a learning deficit in zebrafish that was prevented by pretreatment with nicotine and physostigmine.

• Mycobiology
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• 제47권2호
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• pp.207-216
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• 2019

Talaromyces marneffei is the only dimorphic species in its genus and causes a fatal systemic mycosis named talaromycosis. Our previous study indicated that knockdown of AcuD gene (encodes isocitrate lyase of glyoxylate bypass) of T. marneffei by RNA interference approach attenuated the virulence of T. marneffei, while the virulence of the AcuD knockout strains was not studied. In this study, T. marneffei-zebrafish infection model was successfully established through hindbrain microinjection with different amounts of T. marneffei yeast cells. After co-incubated at $28^{\circ}C$, the increasing T. marneffei inoculum doses result in greater larval mortality; and hyphae generation might be one virulence factor involved in T. marneffei-zebrafish infection. Moreover, the results demonstrated that the virulence of the ${\Delta}AcuD$ was significantly attenuated in this Zebrafish infection model.

• 한국물환경학회지
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• 제39권3호
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• pp.223-230
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• 2023

Harmful algae blooms have become a serious environmental problem in major river basins in Korea. They are known to produce various algal organic matters (AOMs) including intracellular organic matters (IOMs) and extracellular organic matters (EOMs). Generally AOMs cannot be easily removed by coagulation/flocculation process in conventional drinking water plants. AOMs produced by blue-green algae also include various toxins such as Microcystins, Anatoxin-a, and Saxitoxin known to have harmful effects on living organisms in aquatic environment. In this study, toxic effects of EOMs produced by three different algae species (Microcystis sp., Anabaena sp., and Oscillatoria sp.) on zebrafish were investigated using electroencephalography (EEG) recording method, a technology for recording brain activity. Electroencephalographic changes in zebrafish revealed that a low EOM had a negative effect on zebrafish compared to both Anabaena sp. and Oscillatoria sp. at 30 ppm EOM exposures. This result might be due to Microcystins present in EOMs produced by Microcystis sp. As a result of power spectrum density anallysis, exposure to EOMs produced by Microcystis sp. caused a state of vigilance in zebrafish. This EEG based toxicity test can be used to examine effects of harmful materials at low levels on living organisms in an aquatic system.

• Journal of Microbiology and Biotechnology
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• 제30권5호
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• pp.749-752
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• 2020

In the search for novel, natural melanogenesis inhibitors, a new sesquiterpene, inularin, was isolated from the flowers of Inula britannica, and the structure was determined using spectroscopic and chemical methods. The antimelanogenic effects of inularin on B16F10 melanoma cells and zebrafish embryos were evaluated. Inularin dose-dependently reduced melanocyte-stimulating hormone-induced melanin production and L-DOPA oxidation in B16F10 cells. Zebrafish embryos were used to confirm the antimelanogenic activity. Inularin significantly decreased the pigmentation of embryos compared with untreated controls.

• 한국동물생명공학회지
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• 제35권1호
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• pp.28-34
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• 2020

Imazosulfuron is globally considered as a relatively safe herbicide that controls plant growth by interfering with amino acid synthesis. It is stable, persists in the soil, and has low toxicity; however, studies about the toxic effects of imazosulfuron on non-targeted aquatic vertebrates are scarce. In this study, imazosulfuron was able to induce acute lethality on zebrafish embryos within 48 h. Imazosulfuron also had adverse effects on heartbeats and induced abnormal development with pericardial edema and scoliosis. Moreover, apoptosis and oxidative stress were increased by imazosulfuron in a dose-dependent manner. Thus, all our results showed that imazosulfuron has toxic effects on zebrafish embryogenesis.