In vivo NIR time-resolved measurements of human parietal region enhanced with indocyanine green as a contrast agent

Abstract Visualization of the surgically operated tissues is vital to improve surgical model animals including mouse. Urological surgeries for urethra include series of fine manipulations to treat the increasing number of birth defects such as hypospadias. Hence visualization of the urethral status is vital. Inappropriate urethral surgical procedure often leads to the incomplete wound healing and subsequent formation of urethro-cutaneous fistula or urethral stricture. Application of indocyanine green mediated visualization of the urethra was first performed in the current study. Indocyanine green revealed the bladder but not the urethral status in mouse. Antegrade injection of contrast agent into the bladder enabled to detect the urethral status in vivo. The visualization of the leakage of contrast agent from the operated region was shown as the state of urethral fistula in the current hypospadias mouse model and urethral stricture was also revealed. A second trial for contrast agent was performed after the initial operation and a tendency of accelerated urethral stricture was observed. Thus, assessment of post-surgical conditions of urogenital tissues can be improved by the current analyses on the urethral status.

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Time-Resolved Measurements of in vivo Optical Properties of Piglet Brain

Optical Review ◽

10.1007/s10043-000-0420-3 ◽

2000 ◽

Vol 7 (5) ◽

pp. 420-425 ◽

Cited By ~ 15

Author(s):

Angelo Sassaroli ◽

Fabrizio Martelli ◽

Yukari Tanikawa ◽

Kenji Tanaka ◽

Ryuichiro Araki ◽

...

Keyword(s):

Optical Properties ◽

Time Resolved ◽

Time Resolved Measurements

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In Vivo MRI Visualization of Acute Myocardial Ischemia and Reperfusion in Ferrets by the Persistent Action of the Contrast Agent Gd(BME-DTTA)

Circulation ◽

10.1161/01.cir.92.12.3549 ◽

1995 ◽

Vol 92 (12) ◽

pp. 3549-3559 ◽

Cited By ~ 12

Author(s):

Tamás Simor ◽

Wen-Jang Chu ◽

Lynne Johnson ◽

Andras Safranko ◽

Mark Doyle ◽

...

Keyword(s):

Myocardial Ischemia ◽

Contrast Agent ◽

Acute Myocardial Ischemia ◽

Ischemia And Reperfusion ◽

Myocardial Ischemia And Reperfusion

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Real-time observation of tetrapyrrole binding to an engineered bacterial phytochrome

Communications Chemistry ◽

10.1038/s42004-020-00437-3 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yusaku Hontani ◽

Mikhail Baloban ◽

Francisco Velazquez Escobar ◽

Swetta A. Jansen ◽

Daria M. Shcherbakova ◽

...

Keyword(s):

Real Time ◽

Rational Design ◽

Near Infrared ◽

Fluorescent Proteins ◽

Covalent Bond ◽

Binding Pocket ◽

Tissue Imaging ◽

Covalent Attachment ◽

Time Resolved

AbstractNear-infrared fluorescent proteins (NIR FPs) engineered from bacterial phytochromes are widely used for structural and functional deep-tissue imaging in vivo. To fluoresce, NIR FPs covalently bind a chromophore, such as biliverdin IXa tetrapyrrole. The efficiency of biliverdin binding directly affects the fluorescence properties, rendering understanding of its molecular mechanism of major importance. miRFP proteins constitute a family of bright monomeric NIR FPs that comprise a Per-ARNT-Sim (PAS) and cGMP-specific phosphodiesterases - Adenylyl cyclases - FhlA (GAF) domain. Here, we structurally analyze biliverdin binding to miRFPs in real time using time-resolved stimulated Raman spectroscopy and quantum mechanics/molecular mechanics (QM/MM) calculations. Biliverdin undergoes isomerization, localization to its binding pocket, and pyrrolenine nitrogen protonation in <1 min, followed by hydrogen bond rearrangement in ~2 min. The covalent attachment to a cysteine in the GAF domain was detected in 4.3 min and 19 min in miRFP670 and its C20A mutant, respectively. In miRFP670, a second C–S covalent bond formation to a cysteine in the PAS domain occurred in 14 min, providing a rigid tetrapyrrole structure with high brightness. Our findings provide insights for the rational design of NIR FPs and a novel method to assess cofactor binding to light-sensitive proteins.

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Use of the Highly Biocompatible Au Nanocages@PEG Nanoparticles as a New Contrast Agent for In Vivo Computed Tomography Scan Imaging

Nanoscale Research Letters ◽

10.1186/s11671-020-3286-2 ◽

2020 ◽

Vol 15 (1) ◽

Cited By ~ 2

Author(s):

Yan Gao ◽

Jian Kang ◽

Zhen Lei ◽

Yankun Li ◽

Xifan Mei ◽

...

Keyword(s):

Computed Tomography ◽

Contrast Agent ◽

Computed Tomography Scan ◽

Tomography Scan

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Silica-Coated Fe3O4 Nanoparticles as a Bifunctional Agent for Magnetic Resonance Imaging and ZnII Fluorescent Sensing

Technology in Cancer Research & Treatment ◽

10.1177/15330338211036539 ◽

2021 ◽

Vol 20 ◽

pp. 153303382110365

Author(s):

Lin Qiu ◽

Shuwen Zhou ◽

Ying Li ◽

Wen Rui ◽

Pengfei Cui ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Contrast Agent ◽

Quantum Interference ◽

Inductively Coupled Plasma ◽

Fluorescence Emission ◽

Mri Contrast Agent ◽

Core Shell ◽

Resonance Imaging

Bifunctional magnetic/fluorescent core-shell silica nanospheres (MNPs) encapsulated with the magnetic Fe3O4 core and a derivate of 8-amimoquinoline (N-(quinolin-8-yl)-2-(3-(triethoxysilyl) propylamino) acetamide) (QTEPA) into the shell were synthesized. These functional MNPs were prepared with a modified stöber method and the formed Fe3O4@SiO2-QTEPA core-shell nanocomposites are biocompatible, water-dispersible, and stable. These prepared nanoparticles were characterized by X-ray power diffraction (XRD), transmission electron microscopy (TEM), thermoelectric plasma Quad II inductively coupled plasma mass spectrometry (ICP-MS), superconducting quantum interference device (SQUID), TG/DTA thermal analyzer (TGA) and Fourier transform infrared spectroscopy (FTIR). Further application of the nanoparticles in detecting Zn2+ was confirmed by the fluorescence experiment: the nanosensor shows high selectivity and sensitivity to Zn2+ with a 22-fold fluorescence emission enhancement in the presence of 10 μM Zn2+. Moreover, the transverse relaxivity measurements show that the core-shell MNPs have T2 relaxivity (r2) of 155.05 mM−1 S−1 based on Fe concentration on the 3.0 T scanner, suggesting that the compound can be used as a negative contrast agent for MRI. Further in vivo experiments showed that these MNPs could be used as MRI contrast agent. Therefore, the new nanosensor provides the dual modality of magnetic resonance imaging and optical imaging.

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Influence of Oxidative Stress on Time-Resolved Oxygen Detection by [Ru(Phen)3]2+ In Vivo and In Vitro

Molecules ◽

10.3390/molecules26020485 ◽

2021 ◽

Vol 26 (2) ◽

pp. 485

Author(s):

Veronika Huntosova ◽

Denis Horvath ◽

Robert Seliga ◽

Georges Wagnieres

Keyword(s):

Oxidative Stress ◽

Tissue Oxygenation ◽

Intact Cell ◽

Molecular Probes ◽

Stress Factors ◽

Time Resolved ◽

Invasive Approach ◽

Oxygen Detection

Detection of tissue and cell oxygenation is of high importance in fundamental biological and in many medical applications, particularly for monitoring dysfunction in the early stages of cancer. Measurements of the luminescence lifetimes of molecular probes offer a very promising and non-invasive approach to estimate tissue and cell oxygenation in vivo and in vitro. We optimized the evaluation of oxygen detection in vivo by [Ru(Phen)3]2+ in the chicken embryo chorioallantoic membrane model. Its luminescence lifetimes measured in the CAM were analyzed through hierarchical clustering. The detection of the tissue oxygenation at the oxidative stress conditions is still challenging. We applied simultaneous time-resolved recording of the mitochondrial probe MitoTrackerTM OrangeCMTMRos fluorescence and [Ru(Phen)3]2+ phosphorescence imaging in the intact cell without affecting the sensitivities of these molecular probes. [Ru(Phen)3]2+ was demonstrated to be suitable for in vitro detection of oxygen under various stress factors that mimic oxidative stress: other molecular sensors, H2O2, and curcumin-mediated photodynamic therapy in glioma cancer cells. Low phototoxicities of the molecular probes were finally observed. Our study offers a high potential for the application and generalization of tissue oxygenation as an innovative approach based on the similarities between interdependent biological influences. It is particularly suitable for therapeutic approaches targeting metabolic alterations as well as oxygen, glucose, or lipid deprivation.

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Biocompatibility of Bacterial Magnetosomes as MRI Contrast Agent: A Long-Term In Vivo Follow-Up Study

Nanomaterials ◽

10.3390/nano11051235 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1235

Author(s):

Xiaohui Nan ◽

Wenjia Lai ◽

Dan Li ◽

Jiesheng Tian ◽

Zhiyuan Hu ◽

...

Keyword(s):

Contrast Agent ◽

Magnetic Domain ◽

Bilayer Membrane ◽

The Body ◽

Mri Contrast Agent ◽

Mri Imaging ◽

Mri Contrast

Derived from magnetotactic bacteria (MTB), magnetosomes consist of magnetite crystals enclosed within a lipid bilayer membrane and are known to possess advantages over artificially synthesized nanoparticles because of the narrow size distribution, uniform morphology, high purity and crystallinity, single magnetic domain, good biocompatibility, and easy surface modification. These unique properties have increasingly attracted researchers to apply bacterial magnetosomes (BMs) in the fields of biology and medicine as MRI imaging contrast agents. Due to the concern of biosafety, a long-term follow-up of the distribution and clearance of BMs after entering the body is necessary. In this study, we tracked changes of BMs in major organs of mice up to 135 days after intravenous injection using a combination of several techniques. We not only confirmed the liver as the well-known targeted organs of BMs, but also found that BMs accumulated in the spleen. Besides, two major elimination paths, as well as the approximate length of time for BMs to be cleared from the mice, were revealed. Together, the results not only confirm that BMs have high biocompatibility, but also provide a long-term in-vivo assessment which may further help to forward the clinical applications of BMs as an MRI contrast agent.

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