1,721,047 research outputs found
Beta glucan enhances the wound healing process in zebrafish
Full text linkβ-glucans are natural compounds that interact with the innate immune system. Macrophages play an important role in wound healing process and appear to act as the key regulatory cells for skin repair by removing dead tissues and killing pathogens. Macrophages also produce growth factors that stimulate cells involved in wound healing (production of extracellular matrix). Discovering natural products which may enhance the wound healing process in fish, has numerous health benefits and 1,3-1,6 ß-glucans may reduce the negative effect of stress, inflammatory reactions, and secondary infections. In this study, the effects on wound healing process in zebrafish (Danio rerio) of 1,3-1,6 ß-glucan extracted from yeast cell wall was investigated.
Ninety female fish were distributed into 3 groups (3 replicates). Two products were used as source of 1,3-1,6 ß-glucan: MacroGard® and new MacroGard (Biorigin©), MI and MII respectively; fish daily feed intake was estimated in advance (3.88% BW) and both MI and MII included into the feed for reaching the dose of 12.5 mg kg-1 BW. Treatments started 2 weeks before injuring. Afterwards, two circular shape wounds were made using a laser source on the dorsal edge of the abdomen. Wounds were then digitally photographed at 2, 4, 10, 16, 20, 30 days post wound (dpw). Wound area was measured by Image J® software and wound size given as a mean of the two wounds for each fish.
The first clear differences of wound sizes (1.882, 1.725 and 1.665 mm2, for Control, MI and MII, respectively) were observed already at 4 dpw and differences were statistically significant between MI and MII compared to Control group (P<0.05); this early effect seems to suggest a rapid influx of immune cells to a wound in particular when "activated" by 1,3-1,6 ß-glucan (Paul and Fend 2009). Again, at 16 dpw groups MI (0.766 mm2) and MII (0.634 mm2) showed significantly (P<0.05) lower wound area than Control (0.994 mm2); at 20 dpw, wound area of MII (0.518 mm2) was significantly (P<0.05) different from Control (0.702 mm2) and MI (0.713 mm2). Analysis of final wound status (at 30 dpw) showed that 67.9% of fish from MII group had completely healed wounds while that was significantly (P<0.05) lower with 23.1% and 41.4% in control and MI groups, respectively suggesting that MII has better wound healing potential than MI.
The present study demonstrate that 1,3-1,6 ß-glucan (MacroGard®) have potential to be applied as natural wound healing agent in fish. Particularly interesting seems mainly to be their early effect that may imply a higher protection from possible secondary infections. However, further studies are required to determine the optimal feed inclusion in diets for different fish species as well as to explain the slightly higher wound healing effects observed for MII than MI
EFFECTS OF 1,3-1,6 ß-GLUCAN FEED INCLUSION ON CAUDAL FIN REGENERATION PERFORMANCES OF ZEBRAFISH Danio rerio
Full text linkZebrafish (Danio rerio) are considered an interesting animal model for studying the tissue regeneration mechanisms because able to regrow amputated fins. Neutrophils and macrophages have shown functionally important role in tissue repair. Macrophages appear to act as the key regulatory cells for skin repair by removing dead tissues and killing pathogens. Macrophages also produce growth factors that stimulate other cells involved in wound healing. Since β-glucans may "activate" immune cells and macrophages in particular, our hypothesis is that they may positively affect the tissue regeneration process. For these reasons, we investigated the effect 1,3-1,6 β-glucan (extract form yeast cell wall) on caudal fin regeneration in zebrafish.
Ninety fish were distributed into 3 groups (3 replicates). Two products were used as source of 1,3-1,6 ß-glucan: MacroGard® and new MacroGard (Biorigin©), MI and MII, respectively. Fish daily feed intake was estimated in advance (3.75% BW) and both MI and MII included into the feed for reaching the dose of 12.5 mg kg-1 BW. Feeding treatment with MI and MII was started just after amputation. The fin regeneration process was observed and described by measuring the fin regenerated area (RA=(x dpa fin area/pre-amputation fin area)*100) and calculating the daily regenerated area (DRA=(x dpa fin area-x+1 dpa fin area)/pre-amputation fin area)*100). The fin regeneration process is also described by a quadratic equation.
MacroGard® showed a significantly (P0.05) were observed between the two experimental groups.
Further studies are necessary for understanding the mode of action of 1,3-1,6 ß-glucan on fin regeneration
whole-brain imaging of zebrafish larvae using three-dimensional fluorescence microscopy
No full textAs a vertebrate model animal, larval zebrafish are widely used in neuroscience and provide a unique opportunity to monitor whole-brain activity at the cellular resolution. Here, we provide an optimized protocol for performing whole-brain imaging of larval zebrafish using three-dimensional fluorescence microscopy, including sample preparation and immobilization, sample embedding, image acquisition, and visualization after imaging. The current protocol enables in vivo imaging of the structure and neuronal activity of a larval zebrafish brain at a cellular resolution for over 1 h using confocal microscopy and custom-designed fluorescence microscopy. The critical steps in the protocol are also discussed, including sample mounting and positioning, preventing bubble formation and dust in the agarose gel, and avoiding motion in images caused by incomplete solidification of the agarose gel and paralyzation of the fish. The protocol has been validated and confirmed in multiple settings. This protocol can be easily adapted for imaging other organs of a larval zebrafish.
An indole–based near–infrared fluorescent “Turn–On” probe for H2O2: Selective detection and ultrasensitive imaging of zebrafish gallbladder
No full textFluorescent probes play essential roles in medical imaging, where the researchers can select one of many molecules to use to help monitor the status of living systems under investigation. To date, a few scaffolds that allow the in vivo detection of H2O2 are available only. Herein, we provide a highly sensitive and selective near-infrared fluorescent probe that detects H2O2 based on the ICT sensing mechanism. We report the first indole-incorporated fluorescent probe Indo-H2O2 that allows H2O2 detection with a LOD of 25.2 nM featuring a boronate group conjugated to an indole scaffold; the boronate cleaves upon reaction with H2O2. A 5-membered malononitrile derivative was incorporated; Indo-H2O2 has near-infrared (NIR) properties and the reaction time is low (similar to 25 min) compared to other related probes. Indo-H2O2 was successfully employed in both endogenous and exogenous imaging trials of H2O2 in living cells. Indo-H2O2 also allows the real-time monitoring of H2O2 in vivo. It preferentially accesses the gallbladder of zebrafish. Our findings support Indo-H2O2 as a highly sensitive fluorescent NIR probe for detecting H2O2, and an idea to incorporate a central indole unit in future fluorescent probe designs.
KRIVET-WorldBank-CIVTE Workshop
Full text link○ 한국의 직업교육 현황 및 발전 방향 (KRIVET : 강경종) 1
○ Current Status and Direction of Vocational Education in Korea (KRIVET : Kang, Kyeong Jong) 33
○ 한국의 직업교육과 평생교육 체계 (KRIVET : 황규희) 47
○ Vocational Education and Lifelong Learning in South Korea (KRIVET : Hwang, Gyu Hee) 63
○ 한국의 산학협력 정책 및 주요 현황 (KRIVET : 김철희) 81
○ Industry-Academia Cooperation Policy of Korea (KRIVET : Kim, Cheol Hee) 93
○ 한국의 자격증 체제와 그 효과성에 관한 연구 - 전기 분야 자격증을 중심으로- (KRIVET : 이상준) 99
○ 최근 중국 직업 교육의 상황과 향후 개혁 발전 과제 (CIVTE : 황요) 125
○ 평생 교육 발전 추진과 학습형 사회 건설 촉진 (CIVTE : 리유지엔통) 151
○ 직업 교육 산학협동 (CIVTE : 덩저민) 183
○ 중국의 직업 자격증 제도 (CIVTE : 리유펑) 20
Feeding of nano scale oats β-glucan enhances the host resistance against Edwardsiella tarda and protective immune modulation in zebrafish larvae
Full text linkIn this study, we prepared and characterized the oats origin of nano scale β-glucan (NBG) and investigated the immunomodulatory properties in zebrafish larvae. Newly prepared NBG (average particle size of 465 nm) was fully soluble in water. Zebrafish larvae survival rate was increased against pathogenic bacteria Edwardsiella tarda, when NBG was added to the water (500 μg/mL) compared to NBG non-exposed controls. Moreover, quantitative real time PCR (qRT-PCR) results showed up-regulation of immune functional genes including TNF-α, IL-1β, β-defensin, lysozyme, IL 10, IL 12 and C-Rel indicating higher survival rate could be due to stronger immunomodulatory function of NBG (500 μg/mL). Thus, non-toxic, water soluble and biodegradable NBG from oats could be considered as the potential immunostimulant for larval aquaculture
Lyso-H2S: A Mycophenolic Acid-Derived Probe for Ultra-Low Toxicity, Intracellular H2S Detection, and Zebrafish Model Validation
No full textIn several biological processes, H2S is known to function as an endogenous gaseous agent. It is very necessary to monitor H2S and relevant physiological processes in vivo. Herein, a new type of fluorophore with a reliable leaving group allows for excited-state intramolecular transfer characteristics (ESIPT), inspired by mycophenolic acid. A morpholine ring was connected at the maleimide position of the probe to target the lysosome. Subsequently, the dinitrophenyl group known for a photoinduced electron transfer (PET) effect, was connected to allow for an effective "turn-on" probe Lyso-H2S. Lyso-H2S demonstrated strong selectivity towards H2S, a large Stokes shift (111 nm), and an incredibly low detection limit (41.8 nM). The imaging of endogenous and exogenous H2S in living cells (A549 cell line) was successfully achieved because of the specificity and ultra-low toxicity (100 % cell viability at 50 mu M concentration of Lyso-H2S.) Additionally, Lyso-H2S was also employed to visualize the activity of H2S in the gallbladder and intestine in a living zebrafish model. This is the first report of a fluorescent probe to track H2S sensing in specific organ systems to our knowledge.
Indo-Gem: An activatable theranostic prodrug, a "Turn-On" fluorescent probe, and a targetable imaging agent in the zebrafish gallbladder system
No full textTheranostics are crucial in both cancer diagnosis and targeted drug delivery, as they enable the simultaneous detection and treatment of disease within a single molecular or conjugated platform. However, theranostics is still facing challenges like real-time tracking for "where" prodrugs are activated in vivo, which poses a significant problem for molecule development. Organ-specific action to inspire the creation of innovative disease-curing technologies that are both accurate and efficient is still an underestimated task. We herein showcase the novel serendipitous gallbladder-targeting indole-based prodrug Indo-Gem for precise imaging-guided cancer therapy. Indo-Gem was prepared by an indole-malononitrile (dye) moiety, attached to the selected parent drug Gemcitabine via a disulfide cleavable linker. Indo-Gem is triggered by DTT with 27-fold fluorescent enhancement at pH 7.4, registering within 21 min. Unlike the most ignored adverse effects in prodrug activation, this indole-based dye targeting in a specific organ region of a zebrafish model via a combination of imaging ability and drug release. This is the first case that employs an indole-based moiety in prodrug design without any use of targeting ligands; the profound success of Indo-Gem and the well-defined mechanism suggest that the indole might serve as a scaffold to create novel therapeutic prodrugs with improved drug potency in future drug development.
In-vivo monitoring of macrophage mitochondrial pH dynamics in zebrafish using an ultrasensitive and water-soluble targeted fluorescent sensor
No full textMitochondrial pH has a key role in cellular metabolism and also may be a sign of pathology. Thus, closely monitoring of minor changes in this value is critical in biological research. However, it proves difficult due to a lack of availability of appropriate probes. A water-soluble fluorescent mitochondrial targeting probe TPP-MpH is reported. The probe has a hemicyanin-based fluorophore, a triphenylphosphonium (TPP) group for mitochondrial targeting and a PEG group for increased water solubility and biocompatibility. The experimental results show that TPP-MpH reflects ultrasensitive responses to different pH values. The experimental results with cell and zebrafish models indicate that TPP-MpH is highly responsive and specific to pH levels, showing excellent stability and minimal toxicity. Confocal fluorescence imaging confirms that TPP-MpH effectively targets mitochondria and accurately monitors their pH fluctuations. To our astonishment, at pH 8.0 and 9.0, TPP-MpH showed expression in specific cells in the gallbladder and liver region of the zebrafish model, these cells are predominantly mitochondria-rich cells that are involved in the uptake of Na+ ions. Hence, these findings open the door to use this probe for further and deep biological studies.
Highly sensitive and rapid detection of hypochlorous acid in aqueous media and its bioimaging in live cells and zebrafish using an ESIPT-driven mycophenolic acid-based fluorescent probe
No full textExcessive production of potent biological oxidants such as HOCl has been implicated in numerous diseases. Thus, it is crucial to develop highly specific and precise methods to detect HOCl in living systems, preferably with molecules that can show a distinct therapeutic effect. Our study introduces the synthesis and application of a highly sensitive fluorescence '' turn-on '' probe, Myco-OCl, based on the mycophenolic acid scaffold with exceptional water solubility. The ESIPT-driven mechanism enables Myco-OCl to specifically and rapidly detect (< 5 s) HOCl with an impressive Stokes shift of 105 nm (lambda(ex) = 417 nm, lambda(em) = 522 nm) and a sub-nanomolar (97.3 nM) detection limit with the detection range of 0 to 50 mu M. The potential of Myco-OCl as an excellent biosensor is evident from its successful application for live cell imaging of exogenous and endogenous HOCl. In addition, Myco-OCl enabled us to detect HOCl in a zebrafish inflammatory animal model. These underscore the great potential of Myco-OCl for detecting HOCl in diverse physiological systems. Our findings thus offer a highly promising tool for detecting HOCl in living organisms.
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