Read by QxMD icon Read

Fluorescent imaging

Masataka Yamao, Kazuhiro Aoki, Naoto Yukinawa, Shin Ishii, Michiyuki Matsuda, Honda Naoki
We developed two new FRET imaging measures for intramolecular FRET biosensors, called linearly proportional (LP) and highly contrasting (HC) measures, which can be easily calculated by the fluorescence intensities of donor and acceptor as a ratio between their weighted sums. As an alternative to the conventional ratiometric measure, which non-linearly depends on the fraction of active molecule, we first developed the LP measure, which is linearly proportional to the fraction of active molecules. The LP measure inherently unmixes bleed-through signals and is robust against fluorescence noise...
2016: PloS One
Xi Chen, Qi Li, Xiao-Xi Kan, Ya-Jie Wang, Yu-Jie Li, Qing Yang, Hong-Bin Xiao, Ying Chen, Xiao-Gang Weng, Wei-Yan Cai, Xiao-Xin Zhu
Metastasis of breast cancer is the vital step for malignant progression. During such a process, hematogenous metastasis is an indispensable approach for the dissemination of cancer cells. A platelet, contributes to hypercoagulable state, and is also identified the crucial factor in the coagulation system for supporting metastasis. Therefore, the relationship of a platelet and a tumor cell plays a critical role in tumor cell metastasis. Consequently, inhibiting tumor cell‑induced platelet aggregation (TCIPA) is recongnized as a crucial target on suppression of tumor metastasis such as aspirin (ASA)...
October 19, 2016: Oncology Reports
Hashim Ali Khan, Muhammad Aamir Shahzad
PURPOSE: To report a case of atypical serpiginous choroiditis with previously unreported findings on optical coherence tomographic angiography. CASE REPORT: A 35-year-old otherwise healthy man had a 1-week history of vision loss in his right eye. The visual acuity in right eye was counting fingers at 1 meter. Fundoscopy showed a classic peripapillary serpiginous lesion and a solitary macular lesion. Fundus fluorescein angiography revealed early hypofluorescence of active lesions with gradual increase in fluorescence across the phase of angiogram...
October 25, 2016: Optometry and Vision Science: Official Publication of the American Academy of Optometry
Yong Li, Pei Li, Rong Zhu, Chao Luo, Hao Li, Shanfang Hu, Zhou Nie, Yan Huang, Shouzhuo Yao
Bio-imaging probes for accurately monitoring apoptosis process have extensive significance for cell biological studies and clinical investigations. Herein, a novel multi-functional peptide-tailored gold nanoclusters (AuNCs) has been developed for real-time imaging of caspase-indicated cell apoptosis. The AuNCs nanoprobe was facilely prepared by a one-step peptide-mediated biomineralization with the dye (TRAMA)-tagged peptides specific to caspase 3 as both template agents and the signal switch. Unlike conventional FRET-based fluorescent probes of caspase activity, these nanoprobes relied on the unique quenching effect of AuNCs through the nanosurface energy transfer (NSET) from dye to AuNCs...
October 25, 2016: Analytical Chemistry
Shalev Gihaz, Diána Weiser, Adi Dror, Péter Sátorhelyi, Moran Jerabek-Willemsen, László Poppe, Ayelet Fishman
Two ternary sol-gel matrices, an octyltriethoxysilane-based aliphatic matrix and a phenyltriethoxysilane (PTEOS)-based aromatic matrix, were used to immobilize a methanol-stable variant of lipase from Geobacillus stearothermophilus T6 for the synthesis of biodiesel from waste oil. Superior thermal stability of the mutant versus the wildtype in methanol was confirmed by intrinsic protein fluorescence measurements. The influence of skim milk and soluble E. coli lysate proteins as bulking and stabilizing agents in conjunction with sol-gel entrapment were investigated...
October 25, 2016: ChemSusChem
Simin Zhang, Yanmei Zheng, Shengyan Yin, Jingzhi Sun, Bao Li, Lixin Wu
In this study, a uniform complex dual micelle bearing gadolinium substituted polyoxometalate core, hydrophobic middle, and biocompatible organic shell, which exhibited a uniform size and definite molecular weight and chemical composition, was constructed for fluorescent and magnetic resonance imaging contrast agent, via a simple two-step preparation. A paramagnetic polyoxometalate cluster K13[Gd(β2-SiW11O39)2] was firstly encapsulated with a cationic dendron in 3-generation (D-3) bearing triethylene glycol monomethyl ether terminal groups through ionic substitution...
October 24, 2016: Chemistry: a European Journal
Laura E Edgington-Mitchell, Matthew Bogyo, Martijn Verdoes
Since protease activity is highly regulated by structural and environmental influences, the abundance of a protease often does not directly correlate with its activity. Because in most of the cases it is the activity of a protease that gives rise to its biological relevance, tools to report on this activity are of great value to the research community. Activity-based probes (ABPs) are small molecule tools that allow for the monitoring and profiling of protease activities in complex biological systems. The class of fluorescent quenched ABPs (qABPs), being intrinsically "dark" and only emitting fluorescence after reaction with the target protease, are ideally suited for imaging techniques such as small animal noninvasive fluorescence imaging and live cell fluorescence microscopy...
2017: Methods in Molecular Biology
Li-Li Ji, Meng-Wei Guo, Xiu-Jun Ren, Dong-Yu Ge, Gen-Mao Li, Ya Tu
OBJECTIVE: To investigate the effect of electroacupuncture (EA) treatment on the expression of cyclooxygenase (COX) 2 and microglia in spinal cord by using rat model of neuropathic pain, and to probe into the relationship between COX 2 and microglia. METHODS: The rats were randomly divided into 6 groups, including normal control group, model group, sham group, EA 1 group (distant acupoints + local acupoints), EA 2 group (local acupoints), and EA 3 group (distant acupoints)...
October 24, 2016: Chinese Journal of Integrative Medicine
Giorgio Mirri, Daniël C Schoenmakers, Paul H J Kouwer, Peter Veranič, Igor Muševič, Bogdan Štefane
Fluorescent materials are widely used in biological and material applications as probes for imaging or sensing; however, their customization is usually complicated without the support of an organic chemistry laboratory. Here, we present a straightforward method for the customization of BODIPY cores, which are among the most commonly used fluorescent probes. The method is based on the formation of a new C-C bond through Friedel-Crafts electrophilic aromatic substitution carried out at room temperature. The method presented can be used to obtain completely customized fluorescent materials in one or two steps from commercially available compounds...
October 2016: ChemistryOpen
Kirara Yamaguchi, Toshiaki Murai, Jing-Dong Guo, Takahiro Sasamori, Norihiro Tokitoh
The front cover artwork is provided by the group of Toshiaki Murai at Gifu University (Japan). The image shows structures of the key compounds and the change of the fluorescence. Although electron-donating and -accepting groups are not in the same plane, they show relatively strong fluorescence from blue to orange. For more details, read the full text of the Communication at 10.1002/open.201600059.
October 2016: ChemistryOpen
Sarah L Richardson, Pawel Swietach
During capillary transit, red blood cells (RBCs) must exchange large quantities of CO2 and O2 in typically less than one second, but the degree to which this is rate-limited by diffusion through cytoplasm is not known. Gas diffusivity is intuitively assumed to be fast and this would imply that the intracellular path-length, defined by RBC shape, is not a factor that could meaningfully compromise physiology. Here, we evaluated CO2 diffusivity (DCO2) in RBCs and related our results to cell shape. DCO2 inside RBCs was determined by fluorescence imaging of [H(+)] dynamics in cells under superfusion...
October 25, 2016: Scientific Reports
Chantal Dysli, Muriel Dysli, Martin S Zinkernagel, Volker Enzmann
Fluorescence lifetime imaging ophthalmoscopy (FLIO) was used to investigate retinal autofluorescence lifetimes in mouse models of pharmacologically induced retinal degeneration over time. Sodium iodate (NaIO3, 35 mg/kg intravenously) was used to induce retinal pigment epithelium (RPE) degeneration with subsequent loss of photoreceptors (PR) whereas N-methyl-N-nitrosourea (MNU, 45 mg/kg intraperitoneally) was employed for degeneration of the photoreceptor cell layer alone. All mice were measured at day 3, 7, 14, and 28 after the respective injection of NaIO3, MNU or NaCl (control)...
October 21, 2016: Experimental Eye Research
Bjørn Hagen, Marit Valla, Guro Aune, Merethe Ravlo, Anne Britt Abusland, Elisabeth Araya, Marit Sundset, Solveig Tingulstad
OBJECTIVE: A sentinel lymph node (SLN) strategy may have particular value in endometrial cancer (EC) because a therapeutic effect of lymphadenectomy per se is unproven. The aim was to evaluate indocyanine green (ICG) and near-infrared (NIR) fluorescence mapping using a surgical algorithm. METHODS: From November 2012 through December 2015, women with apparently early stage EC underwent robot-assisted laparoscopic hysterectomy including ICG fluorescence SLN mapping following the Memorial Sloane Kettering Cancer Center (MSKCC) surgical algorithm...
October 21, 2016: Gynecologic Oncology
Shi Gao, Guohao Wang, Zainen Qin, Xiangyu Wang, Guoqing Zhao, Qingjie Ma, Lei Zhu
Photodynamic therapy (PDT) is a promising tumor treatment modality that can convert oxygen into cytotoxic singlet oxygen (SO) via photosensitizer to ablate tumor growth. However, the uncontrolled cancer cell proliferation during tumor development and the oxygen consumption during PDT always result in an insufficient oxygen level in tumors, which can adversely affect the PDT efficiency in turn. We designed an oxygen-generating PDT nanocomplex by encapsulating a manganese dioxide nanoparticle (MnO2 NP) in an indocyanine green (ICG) modified hyaluronic acid nanoparticle (HANP) to overcome this limitation...
October 19, 2016: Biomaterials
Kalle Kipper, Ebba Gregorsson Lundius, Vladimir Curic, Ivana Nikic, Edward A Lemke, Manfred Wiessler, Johan Elf
Small synthetic fluorophores are in many ways superior to fluorescent proteins as labels for imaging. A major challenge is to use them for a protein-specific labeling in living cells. Here, we report on our use of noncanonical amino acids that are genetically encoded via the pyrrolysyl-tRNA/pyrrolysyl-RNA synthetase pair at artificially introduced TAG codons in a recoded E. coli strain. The strain is lacking endogenous TAG codons and the TAG-specific release factor RF1. The amino acids contain bioorthogonal groups that can be clicked to externally supplied dyes, thus enabling protein-specific labeling in live cells...
October 24, 2016: ACS Synthetic Biology
Brennan S Dirk, Logan R Van Nynatten, Jimmy D Dikeakos
Viruses must continuously evolve to hijack the host cell machinery in order to successfully replicate and orchestrate key interactions that support their persistence. The type-1 human immunodeficiency virus (HIV-1) is a prime example of viral persistence within the host, having plagued the human population for decades. In recent years, advances in cellular imaging and molecular biology have aided the elucidation of key steps mediating the HIV-1 lifecycle and viral pathogenesis. Super-resolution imaging techniques such as stimulated emission depletion (STED) and photoactivation and localization microscopy (PALM) have been instrumental in studying viral assembly and release through both cell-cell transmission and cell-free viral transmission...
October 19, 2016: Viruses
Lydia Sauer, Sven Peters, Johanna Schmidt, Dietrich Schweitzer, Matthias Klemm, Lisa Ramm, Regine Augsten, Martin Hammer
PURPOSE: To investigate the impact of macular pigment (MP) on fundus autofluorescence (FAF) lifetimes in vivo by characterizing full-thickness idiopathic macular holes (MH) and macular pseudo-holes (MPH). METHODS: A total of 37 patients with MH and 52 with MPH were included. Using the fluorescence lifetime imaging ophthalmoscope (FLIO), based on a Heidelberg Engineering Spectralis system, a 30° retinal field was investigated. FAF decays were detected in a short (498-560 nm; ch1) and long (560-720 nm; ch2) wavelength channel...
October 24, 2016: Acta Ophthalmologica
Xiaofeng Wu, Lihong Li, Wen Shi, Qiuyu Gong, Huimin Ma
Fluorescence imaging of tyrosinase (a cancer biomarker) in living organisms is of great importance for biological studies. However, selective detection of tyrosinase remains a great challenge because current fluorescent probes that contain the 4-hydroxyphenyl moiety show similar fluorescence responses to both tyrosinase and some reactive oxygen species (ROS), thereby suffering from ROS interference. Herein, a new tyrosinase-recognition 3-hydroxybenzyloxy moiety, which exhibits distinct fluorescence responses for tyrosinase and ROS, is proposed...
October 24, 2016: Angewandte Chemie
Raj Kumar Koninti, Sandeep Palvai, Sagar Satpathi, Sudipta Basu, Partha Hazra
Mesoporous silica nano-channel (MCM-41) based molecular switching of a biologically important anticancer drug, namely, ellipticine (EPT) has been utilized to probe its efficient loading onto MCM-41, and its subsequent release to intra-cellular biomolecules, like DNA. By exploiting various spectroscopic techniques (like, steady state fluorescence, time-resolved fluorescence and circular dichroism), it has been shown that EPT can be easily translocated from MCM-41 to DNA without using any external stimulant. Blue emission of EPT in a polar aprotic solvent, i...
October 24, 2016: Nanoscale
Ying-Feng Hsu, Yu-Hsun Chen, Chih-Wei Chang
We performed comprehensive studies on the photoluminescence properties of the carbon dots prepared from citric acid (C-dots(CA)) and citric acid + ethylenediamine (C-dots(CA+EDA)). The cryogenic experiment confirmed that the excitation dependent fluorescence and the spectral relaxation dynamics of the C-dots are associated with the presence of multiple emissive states/species in the C-dots instead of solvation dynamics. Moreover, we also compared the size of the C-dots estimated from the TEM/AFM images and fluorescence anisotropy methods...
October 24, 2016: Physical Chemistry Chemical Physics: PCCP
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"