A new kind of rhodamine-based fluorescence turn-on probe for monitoring ATP in mitochondria

Liu, Yifan,Lee, Dayoung,Wu, Di,Swamy, K.M.K.,Yoon, Juyoung Elsevier 2018 Sensors and actuators. B Chemical Vol.265 No.-

<P><B>Abstract</B></P> <P>We have developed a new kind of colorimetric and fluorescence “turn-on” probe based on rhodamine derivatives for the detection of adenosine-5′-triphosphate (ATP) through hydrogen bond interactions. Upon the addition of 5 mM ATP, the probe 1 shows a 65-fold enhancement in fluorescence intensity and a color change from colorless to pink. The probe 2 also shows very obvious color and fluorescence change with the presence of ATP. The experimental results show that this kind of probe has high specificity towards ATP over other anions, metal ions, and other nucleoside polyphosphates, except ADP. The enhanced emission and naked eye changes are attributed to spirolactam ring-opening, which is pH independent (pH (4.0–7.4)). The more important finding from our results is that the electron withdrawing group in the chain decreases the binding ability to ATP. The live cell imaging experiments in Hela cells indicated that probe <B>2</B> has cell permeability, and mainly locates to mitochondria.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Three new rhodamine derivatives bearing thiourea group are synthesized and reported as chemosensors for ATP. </LI> <LI> Probe <B>1, 2</B> and <B>3</B> showed distinct colorimetric and fluorescence changes with ATP. </LI> <LI> Probe <B>2</B> was successfully applied to monitor ATP in mitochondria. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A bispyrene derivative as a selective fluorescent probe for RNA

Liu, Yifan,Jun, Eun Jin,Kim, Gyoungmi,Lee, Ae-Ree,Lee, Joon-Hwa,Yoon, Juyoung The Royal Society of Chemistry 2014 Chemical communications Vol.50 No.19

<P>A novel bispyrene compound was synthesized to selectively detect RNA through excimer emission “turn-on” in aqueous solution at physiological pH (7.4). The compound was used to successfully image RNA in HeLa cells.</P> <P>Graphic Abstract</P><P>A novel bispyrene compound was synthesized to selectively detect RNA through excimer emission “turn-on” at physiological pH. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cc49430f'> </P>

Preparation and investigation of Dy³⁺-doped Ca₉LiGd_2/3(PO₄)₇ single-phase full-color phosphor

Liu, Shihua,Liu, Simei,Wang, Jingjing,Sun, Pengfei,Zhong, Yifan,Jeong, Jung Hyun,Deng, Bin,Yu, Ruijin Elsevier 2018 Materials research bulletin Vol.108 No.-

<P><B>Abstract</B></P> <P>Novel single-phased white-light-emitting Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:<I>x</I>Dy<SUP>3+</SUP> (<I>x</I> = 0.02, 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30) β-Ca<SUB>3</SUB>(PO<SUB>4</SUB>)<SUB>2</SUB>-type phosphate phosphors were synthesized. The phase structure, luminescence, and thermal stability of the phosphors were characterized by X-ray powder diffraction analysis, photoluminescence excitation and emission spectra, thermal quenching, and decay curves. XRD analysis confirmed the phase formation of Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:Dy<SUP>3+</SUP> materials. Under the excitation of 352 nm, the emission of the Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:0.20Dy<SUP>3+</SUP> sample centered at blue (488 nm) and yellow (580 nm), which corresponded to <SUP>4</SUP>F<SUB>9/2</SUB>–<SUP>6</SUP>H<SUB>15/2</SUB> transition and <SUP>4</SUP>F<SUB>9/2</SUB>–<SUP>6</SUP>H<SUB>13/2</SUB> transition. The optimum dopant concentration of Dy<SUP>3+</SUP> ions was around 20 mol%, and the critical transfer distance of Dy<SUP>3+</SUP> was calculated as 18 Å. The thermal-quenching temperature was above 500 K for Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:0.20Dy<SUP>3+</SUP>. The developed phosphor has a great potential as a single-component white-light-emitting phosphor for UV-light-emitting diodes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel single-phased Ca<SUB>9</SUB>LiGd<SUB>2/3</SUB>(PO<SUB>4</SUB>)<SUB>7</SUB>:<I>x</I>Dy<SUP>3+</SUP> phosphor was firstly synthesized. </LI> <LI> Its structure, luminescent properties are well studied and characterized. </LI> <LI> It was promising as a single-component white-light-emitting phosphor for w-LEDs. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Fluorescent and Colorimetric Chemosensors for Anions, Metal Ions, Reactive Oxygen Species, Biothiols, and Gases

Yifan Liu,Ying Hu,이송이,이다영,윤주영 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.10

Colorimetric and fluorescent chemosensors have been actively studied in recent years, and this article covers our contributions to colorimetric and fluorescent chemosensors in detecting anions, metal ions, reactive oxygen species (ROS), reactive nitrogen species (RNS), biothiols, and gases. The chemosensors discussed in this article are categorized according to their corresponding analytes, and the final part is devoted to polydiacetylene-based chemosensors. We hope that this article will be beneficial in the design of chemosensors for various important analytes.

Green synthesis of fluorescent carbon dots from carrot juice for in vitro cellular imaging

Yang Liu,Yanan Liu,Mira Park,Soo-Jin Park,Yifan Zhang,Md Rashedunnabi Akanda,Byung-Yong Park,Hak Yong Kim 한국탄소학회 2017 Carbon Letters Vol.21 No.-

We report the use of carrot, a new and inexpensive biomaterial source, for preparing high quality carbon dots (CDs) instead of semi-conductive quantum dots for bioimaging application. The as-derived CDs possessing down and up-conversion photoluminescence features were obtained from carrot juice by commonly used hydrothermal treatment. The corresponding physiochemical and optical properties were investigated by electron microscopy, fluorescent spectrometry, and other spectroscopic methods. The surfaces of obtained CDs were highly covered with hydroxyl groups and nitrogen groups without further modification. The quantum yield of as-obtained CDs was as high as 5.16%. The cell viability of HaCaT cells against a purified CD aqueous solution was higher than 85% even at higher concentration (700 μg mL−1) after 24 h incubation. Finally, CD cultured cells exhibited distinguished blue, green, and red colors, respectively, during in vitro imaging when excited by three wavelength lasers under a confocal microscope. Offering excellent optical properties, biocompatibility, low cytotoxicity, and good cellular imaging capability, the carrot juice derived CDs are a promising candidate for biomedical applications.

The effects of deletion of cellobiohydrolase genes on carbon source-dependent growth and enzymatic lignocellulose hydrolysis in Trichoderma reesei

Ren Meibin,Wang Yifan,Liu Guoxin,Zuo Bin,Zhang Yuancheng,Wang Yunhe,Liu Weifeng,Liu Xiangmei,Zhong Yaohua 한국미생물학회 2020 The journal of microbiology Vol.58 No.8

The saprophytic fungus Trichoderma reesei has long been used as a model to study microbial degradation of lignocellulosic biomass. The major cellulolytic enzymes of T. reesei are the cellobiohydrolases CBH1 and CBH2, which constitute more than 70% of total proteins secreted by the fungus. However, their physiological functions and effects on enzymatic hydrolysis of cellulose substrates are not sufficiently elucidated. Here, the cellobiohydrolase-encoding genes cbh1 and cbh2 were deleted, individually or combinatively, by using an auxotrophic marker-recycling technique in T. reesei. When cultured on media with different soluble carbon sources, all three deletion strains (Δcbh1, Δcbh2, and Δcbh1Δcbh2) exhibited no dramatic variation in morphological phenotypes, but their growth rates increased apparently when cultured on soluble cellulase-inducing carbon sources. In addition, Δcbh1 showed dramatically reduced growth and Δcbh1Δcbh2 could hardly grew on microcrystalline cellulose (MCC), whereas all strains grew equally on sodium carboxymethyl cellulose (CMC-Na), suggesting that the influence of the CBHs on growth was carbon source-dependent. Moreover, five representative cellulose substrates were used to analyse the influence of the absence of CBHs on saccharification efficiency. CBH1 deficiency significantly affected the enzymatic hydrolysis rates of various cellulose substrates, where acid pre-treated corn stover (PCS) was influenced the least. CBH2 deficiency reduced the hydrolysis of MCC, PCS, and acid pre-treated and delignified corncob but improved the hydrolysis ability of filter paper. These results demonstrate the specific contributions of CBHs to the hydrolysis of different types of biomass, which could facilitate the development of tailor-made strains with highly efficient hydrolysis enzymes for certain biomass types in the biofuel industry.

Enhancing aircraft engine remaining useful life prediction via multiscale deep transfer learning with limited data

LIU QIAN,Zhang Zhiyao,GUO PENG,WANG YIFAN,Liang Junxin 한국CDE학회 2024 Journal of computational design and engineering Vol.11 No.1

Predicting the remaining useful life (RUL) of the aircraft engine based on historical data plays a pivotal role in formulating maintenance strategies and mitigating the risk of critical failures. None the less, attaining precise RUL predictions often encounters challenges due to the scarcity of historical condition monitoring data. This paper introduces a multiscale deep transfer learning framework via integrating domain adaptation principles. The framework encompasses three integral components: a feature extraction module, an encoding module, and an RUL prediction module. During pre-training phase, the framework leverages a multiscale convolutional neural network to extract distinctive features from data across varying scales. The ensuing parameter transfer adopts a domain adaptation strategy centered around maximum mean discrepancy. This method efficiently facilitates the acquisition of domain-invariant features from the source and target domains. The refined domain adaptation Transformer-based multiscale convolutional neural network model exhibits enhanced suitability for predicting RUL in the target domain under the condition of limited samples. Experiments on the C-MAPSS dataset have shown that the proposed method significantly outperforms state-of-the-art methods.

A new method of phenol degradation by microarc plasma electrolysis

Yifan Zhang,Xiaoyue Jin,Jiahao Yu,Guijun Liu,Ying Wang,Wenbin Xue 한국표면공학회 2017 한국표면공학회 학술발표회 초록집 Vol.2017 No.11

Intestinal Anti-Inflammatory Effects of Selenized Ulva pertusa Polysaccharides in a Dextran Sulfate Sodium-Induced Inflammatory Bowel Disease Model

Yifan Wang,Han Ye,Leke Qiao,Chunying Du,Zhengpeng Wei,Ting Wang,Jingfeng Wang,Ruizhi Liu,Peng Wang 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.3

The purpose of this study was to examine the alleviative effects of selenized polysaccharides from Ulva pertusa (ulvan-Se) on inflammatory bowel disease (IBD) in mice. The dextran sulfate sodium (DSS)-induced IBD mouse model was used to explore the protective effects of ulvan-Se on the intestinal mechanical and immune barrier. At doses less than 1208 mg/kg·bw ulvan-Se showed no significant damage to Institute of Cancer Research (ICR) mice in an acute toxicity test. The results showed that DSS destroyed the mechanical barrier, which includes epithelial cells, while ulvan-Se promoted mRNA expression of tight junction proteins (zonula occludens protein 1, occludin, and claudin-1) and inhibited the infiltration of white blood cells into the intestines. At 100 mg/kg·bw, ulvan-Se enhanced the antioxidant capacity of mice more effectively than the 50 mg/kg·bw ulvan-Se. Furthermore, ulvan-Se improved the intestinal immune barrier by increasing immunoglobulin A and immunoglobulin M, while regulating the levels of interleukin (IL)-1β, interferon-γ, and IL-4. Oral administration of ulvan-Se also suppressed tumor necrosis factor-α, IL-1β, IL-6, and cyclooxygenase-2 mRNA expression mediated by the nuclear factor kappa B pathway. Taken together, our findings reveal that ulvan-Se could be used as a potential alternative supplement for reducing intestinal inflammation in IBD.

A hidden anti-jamming method based on deep reinforcement learning

( Yifan Wang ),( Xin Liu ),( Mei Wang ),( Yu Yu ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.9

In the field of anti-jamming based on dynamic spectrum, most methods try to improve the ability to avoid jamming and seldom consider whether the jammer would perceive the user's signal. Although these existing methods work in some anti-jamming scenarios, their long-term performance may be depressed when intelligent jammers can learn user's waveform or decision information from user's historical activities. Hence, we proposed a hidden anti-jamming method to address this problem by reducing the jammer's sense probability. In the proposed method, the action correlation between the user and the jammer is used to evaluate the hiding effect of the user's actions. And a deep reinforcement learning framework, including specific action correlation calculation and iteration learning algorithm, is designed to maximize the hiding and communication performance of the user synchronously. The simulation result shows that the algorithm proposed reduces the jammer's sense probability significantly and improves the user's anti-jamming performance slightly compared to the existing algorithms based on jamming avoidance.