Changes in Autofluorescence Level of Live and Dead Cells for Mouse Cell Lines
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01.12.2020 |
Kozlova A.A.
Verkhovskii R.A.
Ermakov A.V.
Bratashov D.N.
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Journal of Fluorescence |
10.1007/s10895-020-02611-1 |
0 |
Ссылка
© 2020, Springer Science+Business Media, LLC, part of Springer Nature. Label-free characterization of cell subpopulations is a very promising biomedical approach. Nowadays, there are several label-free methods based on different physical properties such as size, density, stiffness, etc. allowing the characterization of biological objects. However, fluorescence properties are the most suitable feature for the label-free study of tissue and cells. Understanding the autofluorescence level peculiarities of normal and pathological / live and dead cells can become a helpful tool for cells’ metabolic activity, viability evaluation, and diagnostics of a number of diseases. In this study, we applied a series of mouse cell lines (RAW 264.7 - macrophages, L929 - fibroblasts, C2C12 – myoblasts, and B16-F10 – melanoma) to compare cell autofluorescence of live and dead cells under 488 nm laser excitation and found the difference between their autofluorescence depending on a cell state and type.
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New 20-hydroxycholesterol-like compounds with fluorescent NBD or alkyne labels: Synthesis, in silico interactions with proteins and uptake by yeast cells
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01.03.2020 |
Faletrov Y.
Efimova V.
Horetski M.
Tugaeva K.
Frolova N.
Lin Q.
Isaeva L.
Rubtsov M.
Sluchanko N.
Novikova L.
Shkumatov V.
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Chemistry and Physics of Lipids |
10.1016/j.chemphyslip.2019.104850 |
0 |
Ссылка
© 2019 Elsevier B.V. 20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.
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New 20-hydroxycholesterol-like compounds with fluorescent NBD or alkyne labels: Synthesis, in silico interactions with proteins and uptake by yeast cells
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01.03.2020 |
Faletrov Y.
Efimova V.
Horetski M.
Tugaeva K.
Frolova N.
Lin Q.
Isaeva L.
Rubtsov M.
Sluchanko N.
Novikova L.
Shkumatov V.
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Chemistry and Physics of Lipids |
10.1016/j.chemphyslip.2019.104850 |
0 |
Ссылка
© 2019 Elsevier B.V. 20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.
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New 20-hydroxycholesterol-like compounds with fluorescent NBD or alkyne labels: Synthesis, in silico interactions with proteins and uptake by yeast cells
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01.03.2020 |
Faletrov Y.
Efimova V.
Horetski M.
Tugaeva K.
Frolova N.
Lin Q.
Isaeva L.
Rubtsov M.
Sluchanko N.
Novikova L.
Shkumatov V.
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Chemistry and Physics of Lipids |
10.1016/j.chemphyslip.2019.104850 |
0 |
Ссылка
© 2019 Elsevier B.V. 20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.
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New 20-hydroxycholesterol-like compounds with fluorescent NBD or alkyne labels: Synthesis, in silico interactions with proteins and uptake by yeast cells
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01.03.2020 |
Faletrov Y.
Efimova V.
Horetski M.
Tugaeva K.
Frolova N.
Lin Q.
Isaeva L.
Rubtsov M.
Sluchanko N.
Novikova L.
Shkumatov V.
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Chemistry and Physics of Lipids |
10.1016/j.chemphyslip.2019.104850 |
0 |
Ссылка
© 2019 Elsevier B.V. 20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.
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тезис
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New 20-hydroxycholesterol-like compounds with fluorescent NBD or alkyne labels: Synthesis, in silico interactions with proteins and uptake by yeast cells
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01.03.2020 |
Faletrov Y.
Efimova V.
Horetski M.
Tugaeva K.
Frolova N.
Lin Q.
Isaeva L.
Rubtsov M.
Sluchanko N.
Novikova L.
Shkumatov V.
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Chemistry and Physics of Lipids |
10.1016/j.chemphyslip.2019.104850 |
0 |
Ссылка
© 2019 Elsevier B.V. 20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.
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тезис
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New 20-hydroxycholesterol-like compounds with fluorescent NBD or alkyne labels: Synthesis, in silico interactions with proteins and uptake by yeast cells
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01.03.2020 |
Faletrov Y.
Efimova V.
Horetski M.
Tugaeva K.
Frolova N.
Lin Q.
Isaeva L.
Rubtsov M.
Sluchanko N.
Novikova L.
Shkumatov V.
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Chemistry and Physics of Lipids |
10.1016/j.chemphyslip.2019.104850 |
0 |
Ссылка
© 2019 Elsevier B.V. 20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.
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тезис
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New 20-hydroxycholesterol-like compounds with fluorescent NBD or alkyne labels: Synthesis, in silico interactions with proteins and uptake by yeast cells
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01.03.2020 |
Faletrov Y.
Efimova V.
Horetski M.
Tugaeva K.
Frolova N.
Lin Q.
Isaeva L.
Rubtsov M.
Sluchanko N.
Novikova L.
Shkumatov V.
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Chemistry and Physics of Lipids |
10.1016/j.chemphyslip.2019.104850 |
0 |
Ссылка
© 2019 Elsevier B.V. 20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.
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Cationic penetrating antioxidants switch off Mn cluster of photosystem II in situ
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01.11.2019 |
Ptushenko V.
Solovchenko A.
Bychkov A.
Chivkunova O.
Golovin A.
Gorelova O.
Ismagulova T.
Kulik L.
Lobakova E.
Lukyanov A.
Samoilova R.
Scherbakov P.
Selyakh I.
Semenova L.
Vasilieva S.
Baulina O.
Skulachev M.
Kirpichnikov M.
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Photosynthesis Research |
10.1007/s11120-019-00657-2 |
0 |
Ссылка
© 2019, Springer Nature B.V. Mitochondria-targeted antioxidants (also known as ‘Skulachev Ions’ electrophoretically accumulated by mitochondria) exert anti-ageing and ROS-protecting effects well documented in animal and human cells. However, their effects on chloroplast in photosynthetic cells and corresponding mechanisms are scarcely known. For the first time, we describe a dramatic quenching effect of (10-(6-plastoquinonyl)decyl triphenylphosphonium (SkQ1) on chlorophyll fluorescence, apparently mediated by redox interaction of SkQ1 with Mn cluster in Photosystem II (PSII) of chlorophyte microalga Chlorella vulgaris and disabling the oxygen-evolving complex (OEC). Microalgal cells displayed a vigorous uptake of SkQ1 which internal concentration built up to a very high level. Using optical and EPR spectroscopy, as well as electron donors and in silico molecular simulation techniques, we found that SkQ1 molecule can interact with Mn atoms of the OEC in PSII. This stops water splitting giving rise to potent quencher(s), e.g. oxidized reaction centre of PSII. Other components of the photosynthetic apparatus proved to be mostly intact. This effect of the Skulachev ions might help to develop in vivo models of photosynthetic cells with impaired OEC function but essentially intact otherwise. The observed phenomenon suggests that SkQ1 can be applied to study stress-induced damages to OEC in photosynthetic organisms.
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Fluorescence Diagnosis in Neurooncology: Retrospective Analysis of 653 Cases
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06.09.2019 |
Goryaynov S.
Okhlopkov V.
Golbin D.
Chernyshov K.
Svistov D.
Martynov B.
Kim A.
Byvaltsev V.
Pavlova G.
Batalov A.
Konovalov N.
Zelenkov P.
Loschenov V.
Potapov A.
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Frontiers in Oncology |
10.3389/fonc.2019.00830 |
0 |
Ссылка
© Copyright © 2019 Goryaynov, Okhlopkov, Golbin, Chernyshov, Svistov, Martynov, Kim, Byvaltsev, Pavlova, Batalov, Konovalov, Zelenkov, Loschenov and Potapov. Objective: This study is to analyze fluorescence sensitivity in the diagnosis of brain and spinal cord tumors. Material and methods: The authors conducted a multicenter retrospective analysis of data on 653 cases in 641 patients: 553 of them had brain tumors and 88 spinal cord tumors. Brain tumor resection was performed in 523 patients, of whom 484 were adults and 39 children. The analyzed series was presented by 320 gliomas, 101 meningiomas, and 72 metastases. A stereotactic biopsy was performed in 20 patients and endoscopic surgery in 10 patients. In all cases, 20 mg/kg of 5–Aminolaevulinic acid was administered orally 2-h before surgery. All surgical interventions were performed with a microscope BLUE 400 to visualize fluorescence, while endoscopic surgery—with an endoscope equipped with a fluorescent module. Fluorescence spectroscopy was conducted in 20 cases of stereotactic biopsies and in 88 cases of spinal cord tumors. Results: Among adult brain tumors operated by microsurgical techniques, meningiomas showed the highest 5-ALA fluorescence sensitivity 94% (n = 95/101), brain metastases 84.7% (n = 61/72), low-grade gliomas 46.4% (n = 26/56), and high-grade gliomas 90.2% (n = 238/264). In children the highest 5-ALA visible fluorescence was observed in anaplastic astrocytomas 100% (n = 4/4) and in anaplastic ependymomas 100% (n = 4/4); in low-grade gliomas it made up 31.8% (n = 7/22). As for the spinal cord tumors in adults, the highest sensitivity was demonstrated by glioblastomas 100% (n = 4/4) and by meningiomas 100% (n = 4/4); Fluorescence was not found in gemangioblastomas (n = 0/6) and neurinomas (n = 0/4). Fluorescence intensity reached 60% (n = 6/10) in endoscopic surgery and 90% (n = 18/20) in stereotactic biopsy. Conclusion: 5-ALA fluorescence diagnosis proved to be most sensitive in surgery of HGG and meningioma (90.2 and 94.1%, respectively). Sensitivity in surgery of intracranial metastases and spinal cord tumors was slightly lower (84.7 and 63.6%, correspondingly). The lowest fluorescence sensitivity was marked in pediatric tumors and LGG (50 and 46.4%, correspondingly). Fluorescence diagnosis can also be used in transnasal endoscopic surgery of skull base tumors and in stereotactic biopsy.
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A novel low-cost approach for the semi-quantitative analysis of carbohydrate-deficient transferrin (CDT) based on fluorescence resonance energy transfer (FRET)
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01.08.2019 |
Musile G.
De Palo E.
Savchuk S.
Shestakova K.
Bortolotti F.
Tagliaro F.
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Clinica Chimica Acta |
10.1016/j.cca.2019.06.003 |
0 |
Ссылка
© 2019 Background and aim: The increase of the carbohydrate-deficient transferrin (CDT) as results of an heavy intake of alcohol for at least two weeks, is a well-known biochemical modification since the middle ‘70s. Notwithstanding the first commercial kit for the diagnosis of chronic alcohol abuse based on this biomarker was commercially accessible already thirty years ago, only expensive analytical methods are currently available for its determination. The present paper shows a new approach intrinsically sensitive and specific, based on a specific derivatization of transferrin, and not requiring sophisticated instrumentation. Methods: The proposed procedure is based on a selective chelation of terbium (III) by transferrin followed by detection using an characteristic Fluorescence Resonance Transfer Energy (FRET) phenomenon (ex 298 nm - em 550 nm). Results: The proposed procedure showed a limit of detection of 2.5 pmol/mL and a reproducibility intra-day and inter-days <15% and 20%, respectively. The results obtained analyzing 40 serum samples using the developed method, were compared with those obtained with HPLC-Vis and an R2 = 0.8854 was found. Conclusions: Considering its main features (low-cost, ease of operation, minimum need of instrumentation) the present method is suitable for application in screening contexts and in non-strictly regulated environments (e.g. clinical diagnosis) as well as in developing countries or remote areas.
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Imaging of oxygen and hypoxia in cell and tissue samples
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01.08.2018 |
Papkovsky D.
Dmitriev R.
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Cellular and Molecular Life Sciences |
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8 |
Ссылка
© 2018, Springer International Publishing AG, part of Springer Nature. Molecular oxygen (O 2 ) is a key player in cell mitochondrial function, redox balance and oxidative stress, normal tissue function and many common disease states. Various chemical, physical and biological methods have been proposed for measurement, real-time monitoring and imaging of O 2 concentration, state of decreased O 2 (hypoxia) and related parameters in cells and tissue. Here, we review the established and emerging optical microscopy techniques allowing to visualize O 2 levels in cells and tissue samples, mostly under in vitro and ex vivo, but also under in vivo settings. Particular examples include fluorescent hypoxia stains, fluorescent protein reporter systems, phosphorescent probes and nanosensors of different types. These techniques allow high-resolution mapping of O 2 gradients in live or post-mortem tissue, in 2D or 3D, qualitatively or quantitatively. They enable control and monitoring of oxygenation conditions and their correlation with other biomarkers of cell and tissue function. Comparison of these techniques and corresponding imaging setups, their analytical capabilities and typical applications are given.
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Interventional treatment methods, fluorescent diagnostic and photodynamic therapy of nonresectable cholangiocarcinoma complicated by jaundice
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01.01.2018 |
Shiryaev A.
Musaev G.
Levkin V.
Reshetov I.
Loshenov M.
Borodkin A.
Volkov V.
Linkov K.
Makarov V.
Jemerikin G.
Schekoturov I.
Ruban M.
Loshenov V.
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Russian Electronic Journal of Radiology |
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0 |
Ссылка
© 2018 Russian Electronic Journal of Radiology.All Rights Reserved. Purpose. To improve diagnostics and effectiveness of treatment in patients with unresectable cholangiocarcinoma complicated by obstructive jaundice. Materials and methods. A total of 28 patients (100%) with unresectable or functionally inoperable cholangiocarcinomas complicated by obstructive jaundice were diagnosed and treated. All patients underwent percutaneous drainage of the ducts under the ultrasound control and fluoroscopy. After reduction of jaundice video fluorescent diagnostic was performed. There was used a special module for that, by means of which a video fluorescent image of the bile ducts tumor was obtained and the degree of photosensitizer accumulation in the tissues was determined. Following photosensitizers were used: Photosens, Radachlorin (Russia) and Photolon (Belorussia). After the videofluorescence diagnostics photodynamic therapy of tumor stricture was conducted. Photodynamic therapy was performed using a fiber-optic system, if necessary, a controllable balloon catheter on the distal segment was used allowing to conduct therapy throughout the stricture more evenly. For the restoration of biliary evacuation nitinol stents were used. Results. In all patients a videofluorescent image of the bile duct tumor was obtained and a high degree of photosensitizer accumulation was determined. At the same time 23 patients (82%) had a malignant lesion confirmed morphologically. The effectiveness of combined treatment in unresectable cholangiocarcinoma was evaluated by life expectancy, the highest was 29 months (mean 14±5 months), but some of patients were under dynamic control for a period of 6 to 17 months. Conclusions. Usage of interventional treatment methods for patients with cholangiocarcinoma complicated by obstructive jaundice improves liver function and decreases jaundice. The combined use of minimally invasive technologies with fluorescent diagnostics and photodynamic therapy allows to increase the median life expectancy and improve the quality of patient’s life.
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Multispectral imaging technique for skin grafts' functional state assessment
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01.01.2018 |
Makarov V.
Pominova D.
Ryabova A.
Saveleva T.
Ignateva I.
Reshetov I.
Loschenov V.
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Proceedings of SPIE - The International Society for Optical Engineering |
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0 |
Ссылка
© COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only. The development of express method for assessing the state of skin graft by the spectroscopic properties of tissue components involved in the healing of the affected skin or healing of skin grafts was carried out in present work. The proposed method for assessing the state of the skin by the spectroscopic properties of tissue components (using photosensitizers, fluorescent dyes (methylene blue and IcG) and nanophotosensitizers aluminum phthalocyanine nanoparticles (NP-AlPc) applied locally) will evaluate the physiological condition of the skin and assess the degree and rate of engraftment or rejection while also controlling several biochemical and physiological parameters in the entire graft, or the whole area of the skin lesions. Such parameters include the oxygenation of hemoglobin in the tissue microvasculature; the blood supply level; blood flow and lymph flow; assessment of intracellular metabolism; assessment of the cellular respiration type (aerobic/anaerobic).To assess the extent of inflammation the spectrally sensitive to biological environment nanoparticles of aluminum phthalocyanine (NP-AlPc) were also used.
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Laser video fluorescence diagnosis of stomach diseases
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01.01.2018 |
Loshchenov M.
Levkin V.
Chernousov A.
Kalyagina N.
Kharnas S.
Zavodnov V.
Linkov G.
Musayev G.
Egorov A.
Karpova R.
Rybin V.
Khorobrykh T.
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Sovremennye Tehnologii v Medicine |
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0 |
Ссылка
© 2019, Privolzhsky Research Medical University. All rights reserved. The aim of the study was to assess the efficiency of the method for registration of video fluorescence of 5-ALA-induced protoporphyrin IX in stomach and esophagus diseases, to adapt it for clinical conditions, i.e. for conducting differential diagnosis and detecting precancer conditions, and to formulate recommendations on the best photosensitizer doses and time of application in order to make the diagnostic procedure for these diseases more accurate. Materials and Methods. Registration of fluorescence for diagnostic purposes was performed on 57 patients with gastropathology (mainly with stomach cancer) with the help of single-channel (n=50) and dual-channel (n=7) laser video fluorescence registration systems. The study was performed using 5-aminolevulinic acid (5-ALA) (Alasens). 39 endoscopic, 18 intraoperative/laparoscopic investigations, and 7 studies on the macropreparation have been performed. Results. When both systems were used, no fluorescence was registered in cases of stomach ulcer, chronic gastritis, massive tumor necrosis and blood admixture in the stomach as well as in the patient with subcompensated stenosis and a stented output section of the stomach without serous membrane invasion and low 5-ALA concentration. In all other cases, a distinct fluorescence was recorded, the data of which may be used for establishing exact diagnosis and choosing further treatment tactics. Conclusion. Laser video fluorescence technique is a promising method for differential diagnosing and definition of the tumor extension process in the stomach and esophagus which can be used as an express method in diagnostically complex cases.
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Comparative experimental study of 5-ALA and 5-ALA Hexyl ester specific activity
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01.01.2018 |
Yakubovskaya R.
Pankratov A.
Filonenko E.
Lukyanets E.
Ivanova-Radkevich V.
Trushin A.
Kaprin A.
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Biomedical Photonics |
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0 |
Ссылка
© 2018 Russian Photodynamic Association. All rights reserved. A comparative experimental study of the specific activity of drugs based on 5-aminolevulinic acid (5-ALA) and its hexyl ester (5-ALA HE) was carried out. Their ability to induce the synthesis of photoactive protoporphyrin IX in the healthy tissues of the rabbit bladder when instilling the drug solutions at various concentrations has been estimated. It was shown that 5-ALA HE results in the induction and accumulation of PPIX in the rabbit bladder epithelium at much lower concentrations than 5-ALA. Thus, a significant increase in the fluorescence intensity in comparison with the control was achieved by instillation of 5-ALA HE solution in the rabbit' bladder at a concentration of only 0.0001% (fluorescence intensity 2.20±0.60 a.u.), and for 5-ALA - only when using a solution at a concentration of 0.3% (fluorescence intensity 2.60±1.02 a.u.).
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Photodynamic therapy of mouse tumor model using chlorin e6- polyvinyl alcohol complex
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01.01.2018 |
Gavrina A.
Shirmanova M.
Aksenova N.
Yuzhakova D.
Snopova L.
Solovieva A.
Тimashev P.
Dudenkova V.
Zagaynova E.
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Journal of Photochemistry and Photobiology B: Biology |
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3 |
Ссылка
© 2017 Elsevier B.V. The use of polymeric carriers to deliver hydrophobic photosensitizers has been widely discussed as a way to improve both fluorescence diagnostic and photodynamic therapy (PDT) of cancers; however, the photophysical and pharmacokinetic parameters, as well as the PDT activity, of such modifications have, until now, only been poorly investigated. The purpose of the present study was to explore the efficacy of PDT with the formulation of the photosensitizer chlorin e6 (Ce6) in combination with polyvinyl alcohol (PVA) in comparison with Ce6 alone and with the clinical drug, Photodithazine in a mouse tumor model. We also investigated the photoactivity of the Ce6-PVA in a model reaction of tryptophan oxidation, analyzed the polymer–Ce6 interaction using fluorescence spectroscopy and atomic-force microscopy, and tested the phototoxicity in vitro. Using fluorescence imaging in vivo we found that injection to mice of Ce6 in a formulation with PVA resulted in a higher tumor-to-normal ratio and greater photobleaching when compared with either the use of Ce6 alone, or with the effects of Photodithazine. Tumor growth study and histological examination of CT26 tumors revealed fast, reproducible tumor regression and more advanced necrosis after PDT with Ce6-PVA. The higher photoactivity of the Ce6-PVA complex was confirmed in a model reaction of tryptophan oxidation and in cultured cells. Therefore, encapsulation of Ce6 in PVA represents a promising strategy for further increasing the selectivity and efficacy of PDT.
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