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102. Red and near‐infrared light induces intracellular Ca2+ flux via the activation of glutamate N‐methyl‐D‐aspartate receptors.

Author

Golovynska, Iuliia, Golovynskyi, Sergii, Stepanov, Yurii V., Garmanchuk, Liudmyla V., Stepanova, Ludmila I., Qu, Junle, and Ohulchanskyy, Tymish Y.

Subjects
METHYL aspartate receptors, GLUTAMATE receptors, NEAR infrared radiation, VISIBLE spectra, HELA cells, LIGHT
Abstract

Red and near‐infrared (NIR) light effect on Ca2+ ions flux through the influence on N‐methyl‐D‐aspartate receptors (NMDARs) and their functioning in HeLa cells was studied in vitro. Cells were irradiated by 650 and 808 nm laser light at different power densities and doses and the obtained effect was compared with that caused by the pharmacological agents. The laser light was found to elevate Ca2+ influx into cell cytoplasm in a dose‐dependent manner without changes of the NMDAR functioning. Furthermore, the light of both wavelengths demonstrated the ability to elevate Ca2+ influx under the pharmacological blockade of NMDARs and also might partially abolish the blockade enhancing Ca2+ influx after selective stimulation of the receptors with NMDA. Simultaneously, the light at moderate doses demonstrated a photobiostimulating effect on cells. Based on our experiments and data reported in the literature, we suggest that the low‐power visible and NIR light can instigate a cell membrane depolarization via nonthermal activation, resulting in the fast induction of Ca2+ influx into cells. The obtained results also demonstrate that NIR light can be used for nonthermal and nonpharmacological stimulation of NMDARs in cancer cells. [ABSTRACT FROM AUTHOR]

Published
2019
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104. Morpho‐Functional Characteristics of Bone Marrow Multipotent Mesenchymal Stromal Cells after Activation or Inhibition of Epidermal Growth Factor and Toll‐Like Receptors or Treatment with DNA Intercalator Cisplatin.

Author

Golovynska, Iuliia, Kalmukova, Olesia, Svitina, Hanna M., Kyryk, Vitaliy M., Shablii, Volodimir A., Senchylo, Nataliya V., Ostrovska, Galyna V., Dzerzhinskyi, Mykola, Stepanov, Yurii V., Golovynskyi, Sergii, Ohulchanskyy, Tymish Y., Liu, Liwei, Garmanchuk, Liudmila V., and Qu, Junle

Abstract

This study is aimed to reveal morphological and functional changes in multipotent mesenchymal stromal cells (MSCs) isolated from the rat bone marrow after: (i) activation of Toll‐like receptors (TLRs) with teichoic acid (TA), (ii) impact on epidermal growth factor (EGF) receptors with activator EGF or inhibitor Herceptin, and (iii) treatment with DNA intercalator Cisplatin. According to our results, TA and EGF cause an increase in the synthesis of glycosaminoglycans, c‐Myc content, and protein in the MSC cytoplasm. It was observed that the cell population in G0 phase decreased and the cell population in G1 phase increased, when compared with control. At the same time, the cell population with a higher nuclear–cytoplasmic ratio (NCR) in S and G2 phases also increased. This indicates the manifestation of the MSC mesenchymal phenotype, exhibiting indirect metabolic signs of the regenerative potential increase. In other experiments, Herceptin was shown to suppress only the stemness signs of MSCs, while Cisplatin seriously affected cell viability in general, reducing synthetic and proliferative activities and causing cell morphology disturbances. © 2018 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Published
2019
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105. Highly Effective Dual-Function Near-Infrared (NIR) Photosensitizer for Fluorescence Imaging and Photodynamic Therapy (PDT) of Cancer

Author

Patel, Nayan, primary, Pera, Paula, additional, Joshi, Penny, additional, Dukh, Mykhaylo, additional, Tabaczynski, Walter A., additional, Siters, Kevin E., additional, Kryman, Mark, additional, Cheruku, Ravindra R., additional, Durrani, Farukh, additional, Missert, Joseph R., additional, Watson, Ramona, additional, Ohulchanskyy, Tymish Y., additional, Tracy, Erin C., additional, Baumann, Heinz, additional, and Pandey, Ravindra K., additional

Published
2016
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106. Targeting T Cell Bioenergetics by Modulating P-Glycoprotein Selectively Depletes Alloreactive T Cells To Prevent Graft-versus-Host Disease

Author

McIver, Zachariah A., primary, Grayson, Jason M., additional, Coe, Benjamin N., additional, Hill, Jacqueline E., additional, Schamerhorn, Gregory A., additional, Ohulchanskyy, Tymish Y., additional, Linder, Michelle K., additional, Davies, Kellie S., additional, Weiner, Roy S., additional, and Detty, Michael R., additional

Published
2016
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109. Light upconverting core-shell nanostructures : nanophotonic control for emerging applications

Author

Chen, Guanying, Ågren, Hans, Ohulchanskyy, Tymish Y., Prasad, Paras N., Chen, Guanying, Ågren, Hans, Ohulchanskyy, Tymish Y., and Prasad, Paras N.

Abstract

Light upconverting nanostructures employing lanthanide ions constitute an emerging research field recognized with wide ramifications and impact in many areas ranging from healthcare, to energy and, to security. The core-shell design of these nanostructures allows us to deliberately introduce a hierarchy of electronic energy states, thus providing unprecedented opportunities to manipulate the electronic excitation, energy transfer and upconverted emissions. The core-shell morphology also causes the suppression of quenching mechanisms to produce efficient upconversion emission for biophotonic and photonic applications. Using hierarchical architect, whereby each shell layer can be defined to have a specific feature, the electronic structure as well as the physiochemical structure of the upconverting nanomaterials can be tuned to couple other electronic states on the surface such as excitations of organic dye molecules or localized surface plasmons from metallic nanostructures, or to introduce a broad range of imaging or therapeutic modalities into a single conduct. In this review, we summarize the key aspects of nanophotonic control of the light upconverting nanoparticles through governed design and preparation of hierarchical shells in the core-shell nanostructures, and review their emerging applications in the biomedical field, solar energy conversion, as well as security encoding., QC 20150420

Published
2015
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110. P-Glycoprotein Modulation Facilitates the Selective Inhibition of Oxidative Phosphorylation in Alloreactive T Cells to Prevent Graft-Versus-Host Disease after Hematopoietic Stem Cell Transplant

Author

McIver, Zachariah A., primary, Phipps, James P, additional, Grayson, Jason M, additional, Hill, Jacqueline E, additional, Schamerhorn, Gregory A, additional, Ohulchanskyy, Tymish Y, additional, Linder, Michelle K, additional, Davies, Kellie S, additional, Weiner, Roy S, additional, and Detty, Michael R, additional

Published
2015
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111. TiO2‐coated fluoride nanoparticles for dental multimodal optical imaging.

Author

Braz, Ana K. S., Moura, Diógenes S., Gomes, Anderson S. L., Ohulchanskyy, Tymish Y., Chen, Guanying, Liu, Maixian, Damasco, Jossana, de Araujo, Renato E., and Prasad, Paras N.

Abstract

Core‐shell nanostructures associated with photonics techniques have found innumerous applications in diagnostics and therapy. In this work, we introduce a novel core‐shell nanostructure design that serves as a multimodal optical imaging contrast agent for dental adhesion evaluation. This nanostructure consists of a rare‐earth‐doped (NaYF4:Yb 60%, Tm 0.5%)/NaYF4 particle as the core (hexagonal prism, ~51 nm base side length) and the highly refractive TiO2 material as the shell (~thickness of 15 nm). We show that the TiO2 shell provides enhanced contrast for optical coherence tomography (OCT), while the rare‐earth‐doped core upconverts excitation light from 975 nm to an emission peaked at 800 nm for photoluminescence imaging. The OCT and the photoluminescence wide‐field images of human tooth were demonstrated with this nanoparticle core‐shell contrast agent. In addition, the described core‐shell nanoparticles (CSNps) were dispersed in the primer of a commercially available dental bonding system, allowing clear identification of dental adhesive layers with OCT. We evaluated that the presence of the CSNp in the adhesive induced an enhancement of 67% scattering coefficient to significantly increase the OCT contrast. Moreover, our results highlight that the upconversion photoluminescence in the near‐infrared spectrum region is suitable for image of deep dental tissue. [ABSTRACT FROM AUTHOR]

Published
2018
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112. (α-NaYbF 4 :Tm 3+ )/CaF 2 Core/Shell Nanoparticles with Efficient Near-Infrared to Near-Infrared Upconversion for High-Contrast Deep Tissue Bioimaging

Author

Kutikov, Artem, Han, Gang, Li, Zhipeng, Agren, Hans, Patel, Nayan J., Pandey, Ravindra K., Song, Jie, Chen, Guanying, Ohulchanskyy, Tymish Y., Prasad, Paras N., and Shen, Jie

Abstract

We describe the development of novel and biocompatible core/shell (α-NaYbF4:Tm3+)/CaF2 nanoparticles which exhibit highly efficient NIRin-NIRout upconversion (UC) for high contrast and deep bioimaging. When excited at ~980 nm, these nanoparticles emit photoluminescence (PL) peaked at ~800 nm. The quantum yield of this UC PL under low power density excitation (~0.3 W/cm2) is 0.6±0.1%. This high UC PL efficiency is realized by suppressing surface quenching effects via hetero-epitaxial growth of a biocompatible CaF2 shell which results in a 35-fold increase in the intensity of UC PL from the core. Small animal whole-body UC PL imaging with exceptional contrast (signal-to-background ratio of 310) is shown using BALB/c mice intravenously injected with aqueously dispersed nanoparticles (700 pmol/kg). High-contrast UC PL imaging of deep tissues is also demonstrated, using a nanoparticle-loaded synthetic fibrous mesh wrapped around rat femoral bone, and a cuvette with nanoparticle aqueous dispersion - covered with a 3.2-cm thick animal tissue (pork).

Published
2012
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116. Enhanced upconversion emission in colloidal (NaYF4:Er3+)/NaYF4 core/shell nanoparticles excited at 1523 nm

Author

Shao, Wei, Chen, Guanying, Damasco, Jossana, Wang, Xianliang, Kachynski, Aliaksandr, Ohulchanskyy, Tymish Y., Yang, Chunhui, Ågren, Hans, Prasad, Paras N., Shao, Wei, Chen, Guanying, Damasco, Jossana, Wang, Xianliang, Kachynski, Aliaksandr, Ohulchanskyy, Tymish Y., Yang, Chunhui, Ågren, Hans, and Prasad, Paras N.

Abstract

In this work, we report on efficient visible and near-IR upconversion emissions in colloidal hexagonal-phase core/shell NaYF4:Er3+/NaYF4 nanoparticles (similar to 38 nm) under IR laser excitation at 1523 nm. Varying amounts of Er3+ dopants were introduced into the core NaYF4:Er3+ nanoparticles, revealing an optimized Er3+ concentration of 10% for the highest luminescent efficiency. An inert epitaxial shell layer of NaYF4 grown onto the core of the NaYF4:Er3+ 10% nanoparticle increased its upconversion emission intensity fivefold due to suppression of surface-related quenching mechanisms, yielding the absolute upconversion efficiency to be as high as similar to 3.9 +/- 0.3% under an excitation density of 18 W/cm(2). The dependence of the intensity of upconversion emission peaks on laser excitation density in the core/shell nanoparticle displayed "saturation effects" at low excitation density in the range of 1.5-18 W/cm(2), which again demonstrates high upconversion efficiency., QC 20140423

Published
2014
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123. Novel Hybrid Compound 4-[(E)-2-phenylethenesulfonamido]-N-hydroxybutanamide with Antimetastatic and Cytotoxic Action: Synthesis and Anticancer Screening

Author

Zborovskii, Yurii L., Orysyk, Viktor V., Golovynska, Iuliia, Dzhus, Olena I., Garmanchuk, Liudmyla V., Stepanov, Yurii V., Khranovska, Natalia, Nehelia, Anatolii O., Golovynskyi, Sergii, Ohulchanskyy, Tymish Y., Qu, Junle, Orysyk, Svitlana I., Pekhnyo, Vasyl I., and Vovk, Myhaylo V.

Abstract

Background: One of the most promising strategies to develop multi-targeted anticancer therapeutics is to introduce to the structure of a potential drug two or more pharmacophores (functional groups or structural fragments), which have antiproliferative, proapoptotic or antimetastatic properties acting via different mechanisms. Objective: To design, synthesize and perform screening of a novel hybrid anticancer compound. Method: A novel hybrid compound 4-[(E)-2-phenylethenesulfonamido]-N-hydroxybutanamide, combining butanehydroxamate and styrenesulfonamide moieties, was designed, synthesized and investigated as a potent antimetastatic and antiproliferative agent. The structure and purity of the synthesized compound were confirmed by 1H NMR, 13C NMR, LC/MS spectroscopy and elemental analysis. The compound was screened for the anticancer activity in vitro against HeLa and in vivo against Lewis lung carcinoma tumor, using an antitumor metalloenzyme inhibitor GM6001 (Ilomastat, Galardin) and Pifithrin-μ as control anticancer agents. Results: It was found that the application of our compound resulted in a high fraction of apoptotic cells in the cell population, along with disruption in the cell cycle profile manifested as arrest of proliferative phases. Furthermore, changes of the morphological properties (i.e., an enhancement of adhesive properties and reduction of the nuclear-to-cytoplasm ratio) were found. The in vivo screening revealed that the compound significantly inhibited the metastasizing process that was manifested by a reduction in the number and volume of metastases. Conclusions: The obtained results demonstrate that our compound can serve as a base for further structure optimization in order to design new highly-effective antimetastatic and antitumor agents.

Published
2018
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124. Use of colloidal upconversion nanocrystals for energy relay solar cell light harvesting in the near-infrared region.

Author

Yuan, Chunze, Chen, Guanying, Prasad, Paras N., Ohulchanskyy, Tymish Y., Ning, Zhijun, Tian, Haining, Sun, Licheng, Aagren, Hans., Yuan, Chunze, Chen, Guanying, Prasad, Paras N., Ohulchanskyy, Tymish Y., Ning, Zhijun, Tian, Haining, Sun, Licheng, and Aagren, Hans.

Abstract

Colloidal upconversion (UC) nanocrystals were explored as energy relay materials for dye-sensitized solar cells for the 1st time. The use of colloidal UC nanocrystals was found to significantly enhance the upconversion efficiency and improve the photocurrent of the cells for low IR irradn. intensity. UC nanocrystals of small size favor infiltration into a TiO2 film and bring higher relay efficiency. Finally, UC nanocrystals can serve as a scattering material to increase the light absorption capability of the cells and increase the overall photocurrent of the cells under simulated sunlight irradn. [on SciFinder(R)], CAPLUS AN 2012:1115046(Journal; Online Computer File)

Published
2012
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125. (alpha-NaYbF4:Tm3+)/CaF2 Core/Shell Nanoparticles with Efficient Near-Infrared to Near-Infrared Upconversion for High-Contrast Deep Tissue Bioimaging

Author

Chen, Guanying, Shen, Jie, Ohulchanskyy, Tymish Y., Patel, Nayan J., Kutikov, Artem, Li, Zhipeng, Song, Jie, Pandey, Ravindra K., Ågren, Hans, Prasad, Paras N., Han, Gang, Chen, Guanying, Shen, Jie, Ohulchanskyy, Tymish Y., Patel, Nayan J., Kutikov, Artem, Li, Zhipeng, Song, Jie, Pandey, Ravindra K., Ågren, Hans, Prasad, Paras N., and Han, Gang

Abstract

We describe the development of novel and biocompatible core/shell (alpha-NaYbF4:Tm3+)/CaF2 nanoparticles that exhibit highly efficient NIRin-NIROut upconversion (UC) for high contrast and deep bioimaging. When excited at similar to 980 nm, these nanoparticles emit photoluminescence (PL) peaked at similar to 800 nm. The quantum yield of this UC PL under low power density excitation (similar to 0.3 W/cm(2)) is 0.6 +/- 0.1%. This high UC PL efficiency is realized by suppressing surface quenching effects via heteroepitaxial growth of a biocompatible CaF2 shell, which results in a 35-fold increase in the intensity of UC PL from the core. Small-animal whole-body UC PL imaging with exceptional contrast (signal-to-background ratio of 310) is shown using BALB/c mice intravenously injected with aqueously dispersed nanoparticles (700 pmol/kg). High-contrast UC PL imaging of deep tissues is also demonstrated, using a nanoparticle-loaded synthetic fibrous mesh wrapped around rat femoral bone and a cuvette with nanoparticle aqueous dispersion covered with a 3.2 cm thick animal tissue (pork)., QC 20121105

Published
2012
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126. Intense Visible and Near-Infrared Upconversion Photoluminescence in Colloidal LiYF4:Er3+ Nanocrystals under Excitation at 1490 nm

Author

Chen, Guanying, Ohulchanskyy, Tymish Y., Kachynski, Aliaksandr, Ågren, Hans, Prasad, Paras N., Chen, Guanying, Ohulchanskyy, Tymish Y., Kachynski, Aliaksandr, Ågren, Hans, and Prasad, Paras N.

Abstract

We report intense upconversion photoluminescence (PL) In colloidal LiYF4:Er(3+)nanocrystals under excitation with telecom-wavelength at 1490 nm. The intensities of two- and three-photon anti-Stokes upconversion PL bands are higher than or comparable to that of the Stokes emission under excitation with low power density in the range 5-120 W/cm(2). The quantum yield of the uptonversion PL was measured to be as high as similar to 1.2 +/- 0.1%, which is almost 4 times higher than the highest upconversion PL quantum yield reported to date for lanthanide-doped nanocrystals In 100 nm sized hexagonal NaYF4:Yb(3+)20%, Er(3+)2% using excitation at similar to 980 nm. A power dependence study revealed that the intensities of all PL bands have linear dependence on the excitation power density, which was explained by saturation effects in the intermediate energy states., QC 20110711

Published
2011
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127. Monodisperse NaYbF4 : Tm3+/NaGdF4 core/shell nanocrystals with near-infrared to near-infrared upconversion photoluminescence and magnetic resonance properties

Author

Chen, Guanying, Ohulchanskyy, Tymish Y., Law, Wing Cheung, Ågren, Hans, Prasad, Paras N., Chen, Guanying, Ohulchanskyy, Tymish Y., Law, Wing Cheung, Ågren, Hans, and Prasad, Paras N.

Abstract

We report core/shell NaYbF4 : Tm3+/NaGdF4 nanocrystals to be used as probes for bimodal near infrared to near infrared (NIR-to-NIR) upconversion photoluminescence (UCPL) and magnetic resonance (MR) imaging. The NaYbF4 : Tm3+ nanocrystals were previously reported to produce the intense NIR-to-NIR UCPL peaked at similar to 800 nm under excitation at similar to 975 nm. We have found that the growth of a NaGdF4 shell on surface of the NaYbF4 : Tm3+ nanocrystals results in the increase in the intensity of UCPL of Tm3+ ions by about 3 times. Unlike biexponential PL decay of NaYbF4 : Tm3+ nanocrystals, the PL decay of NaYbF4 : Tm3+/NaGdF4 core/shell nanocrystals is single exponential and of longer lifetime due to the suppression of surface quenching effects for Tm3+ PL. The growth of a NaGdF4 shell on surface of the NaYbF4 : Tm3+ nanocrystals also provides high MR relaxivity from paramagnetic Gd3+ ions contained in the shell. The T1-weighted MR signal of the (NaYbF4:2% Tm3+)/NaGdF4 nanoparticles was measured to be about 2.6 mM(-1)s(-1). Due to the combined presence of efficient optical and MR imaging capabilities, nanoprobes based on NaYbF4 : Tm3+/NaGdF4 fluoride nanophosphors can be considered as a promising platform for simultaneous bimodal PL and MR bioimaging., QC 20110616

Published
2011
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128. Ultrasmall Monodisperse NaYF4:Yb3+/Tm3+ Nanocrystals with Enhanced Near-Infrared to Near-Infrared Upconversion Photoluminescence

Author

Chen, Guanying, Ohulchanskyy, Tymish Y., Kumar, Rajiv, Ågren, Hans, Prasad, Prasas N., Chen, Guanying, Ohulchanskyy, Tymish Y., Kumar, Rajiv, Ågren, Hans, and Prasad, Prasas N.

Abstract

Photoluminescent NaYF4:Yb3+/Tm3+ nanocrystals are ideally suited for in vitro and in vivo photoluminescence (PL) bioimaging due to their virtue of near-infrared to near-infrared (NIR-to-NIR) upconversion (UC); they display PL with a peak at similar to 800 nm if excited at similar to 980 nm. Here, we report the synthesis of monodisperse NaYF4:Yb3+/Tm3+ nanocrystals of ultrasmall size (7-10 nm) with high UC efficiency. The intensity of their NIR UC emission was demonstrated to increase by up to 43 times along with an increase in the relative content of Yb3+ ions from 20 to 100%, with a corresponding decrease in the Y3+ content from 80 to 0%. The achieved ultrasmall NaYbF4:2% Tm3+ nanocrystals manifest NIR PL emission, which is 3.6 times more intense than that from 25-30 nm sized NaYF4:20% Yb3+/2% Tm3+ nanocrystals, previously synthesized and used for in vitro and in vivo bioimaging. An optimization of both size and UC PL efficiency of NIR-to-NIR nanocrystals provides us with highly efficient optical imaging probes for bioapplications., QC 20101209

Published
2010
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131. Upconversion: Tunable Near Infrared to Ultraviolet Upconversion Luminescence Enhancement in (α‐NaYF4:Yb,Tm)/CaF2 Core/Shell Nanoparticles for In situ Real‐time Recorded Biocompatible Photoactivation (Small 19/2013)

Author

Shen, Jie, primary, Chen, Guanying, additional, Ohulchanskyy, Tymish Y., additional, Kesseli, Samuel J., additional, Buchholz, Steven, additional, Li, Zhipeng, additional, Prasad, Paras N., additional, and Han, Gang, additional

Published
2013
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134. Regioselective Synthesis and Photophysical and Electrochemical Studies of 20-Substituted Cyanine Dye-Purpurinimide Conjugates: Incorporation of NiIIinto the Conjugate Enhances its Tumor-Uptake and Fluorescence-Imaging Ability

Author

Ethirajan, Manivannan, primary, Chen, Ping, additional, Ohulchanskyy, Tymish Y., additional, Goswami, Lalit N., additional, Gupta, Anurag, additional, Srivatsan, Avinash, additional, Dobhal, Mahabeer P., additional, Missert, Joseph R., additional, Prasad, Paras N., additional, Kadish, Karl M., additional, and Pandey, Ravindra K., additional

Published
2013
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138. Imaging pancreatic cancer using surface-functionalized quantum dots

Author

Qian, Jun, Yong, Ken-Tye, Roy, Indrajit, Ohulchanskyy, Tymish Y., Bergey, Earl J., Lee, Hoon Hi, Tramposch, Kenneth M., He, Sailing, Maitra, Anirban, Prasad, Paras N., Qian, Jun, Yong, Ken-Tye, Roy, Indrajit, Ohulchanskyy, Tymish Y., Bergey, Earl J., Lee, Hoon Hi, Tramposch, Kenneth M., He, Sailing, Maitra, Anirban, and Prasad, Paras N.

Abstract

QC 20100525

Published
2007
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139. (α-NaYbF4:Tm3+)/CaF2Core/Shell Nanoparticles with Efficient Near-Infrared to Near-Infrared Upconversion for High-Contrast Deep Tissue Bioimaging

Author

Chen, Guanying, primary, Shen, Jie, additional, Ohulchanskyy, Tymish Y., additional, Patel, Nayan J., additional, Kutikov, Artem, additional, Li, Zhipeng, additional, Song, Jie, additional, Pandey, Ravindra K., additional, Ågren, Hans, additional, Prasad, Paras N., additional, and Han, Gang, additional

Published
2012
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