| 1. |
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| 2. |
- Kudlis, A., et al.
(författare)
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All-optical magnetization control in CrI3 monolayers : A microscopic theory
- 2023
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Ingår i: Physical Review B. - : American Physical Society. - 2469-9950 .- 2469-9969. ; 108:9
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Tidskriftsartikel (refereegranskat)abstract
- Bright excitons in ferromagnetic monolayers of CrI3 efficiently interact with lattice magnetization, which makes all-optical resonant magnetization control possible in this material. Using the combination of ab initio simulations within the Bethe-Salpeter approach, semiconductor Bloch equations, and Landau-Lifshitz equations, we construct a microscopic theory of this effect. By solving numerically the resulting set of coupled equations describing the dynamics of atomic spins and spins of the excitons, we demonstrate the possibility of tunable control of the macroscopic magnetization of a sample.
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| 3. |
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| 4. |
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| 5. |
- Chernov, Alexander I, et al.
(författare)
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Optical properties of graphene nanoribbons encapsulated in single-walled carbon nanotubes
- 2013
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Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 7:7, s. 6346-6353
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Tidskriftsartikel (refereegranskat)abstract
- We report the photoluminescence (PL) from graphene nanoribbons (GNRs) encapsulated in single-walled carbon nanotubes (SWCNTs). New PL spectral features originating from GNRs have been detected in the visible spectral range. PL peaks from GNRs have resonant character, and their positions depend on the ribbon geometrical structure in accordance with the theoretical predictions. GNRs were synthesized using confined polymerization and fusion of coronene molecules. GNR@SWCNTs material demonstrates a bright photoluminescence both in infrared (IR) and visible regions. The photoluminescence excitation mapping in the near-IR spectral range has revealed the geometry-dependent shifts of the SWCNT peaks (up to 11 meV in excitation and emission) after the process of polymerization of coronene molecules inside the nanotubes. This behavior has been attributed to the strain of SWCNTs induced by insertion of the coronene molecules.
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| 6. |
- Fedotov, Pavel V., et al.
(författare)
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Optical Study of Nanotube and Coronene Composites
- 2013
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Ingår i: Journal of Nanoelectronics and Optoelectronics. - : American Scientific Publishers. - 1555-130X .- 1555-1318. ; 8:1, s. 16-22
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Forskningsöversikt (refereegranskat)abstract
- A novel nanomaterial, graphene nanoribbons encapsulated inside single-walled carbon nanotubes (GNR@SWNT), was studied by combined optical methods. This nanomaterial was found to have a bright photoluminescence both in IR and UV-Vis spectral ranges. Its spectral features have a complicated resonant structure different from the features of initial components: coronene molecules and SWNTs. The encapsulation ability appears to correlate strongly with the geometry of SWNTs. A weak interaction between nanotube walls and encapsulated species has been discovered: no evidence of charge or energy transfer has been registered.
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| 7. |
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| 8. |
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| 9. |
- Bragina, O. D., et al.
(författare)
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A direct comparison of the diagnostic efficacy of alternative scaffold- based radiopharmaceuticals [99mTc]Tc-ADAPT6 and [99mTc]Tc-(HE)3-G3 in patients with HER2-positive breast cancer
- 2023
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Ingår i: BYULLETEN SIBIRSKOY MEDITSINY. - 1682-0363 .- 1819-3684. ; 22:3, s. 6-13
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Tidskriftsartikel (refereegranskat)abstract
- Aim. To perform a direct comparison of the diagnostic efficacy of [(99)mTc]Tc-ADAPT6 and [(99)mTc]Tc-(HE)3-G3 in HER2-positive breast cancer patients before the systemic treatment.Materials and methods. The study included 11 patients with HER2-positive breast cancer (T1-4N0-2M0-1) before the initiation of systemic treatment. All patients underwent a radionuclide examination with [(99)mTc]Tc-ADAPT6 and [(99)mTc]Tc-(HE)3-G3 with the interval of 3-4 days. Single-photon emission computed tomography (SPECT) /computed tomography (CT) was performed 2 and 4 hours after [(99)mTc]Tc-ADAPT6 and [(99)mTc]Tc-(HE)3-G3 administration, respectively.Results. The analysis of [(99)mTc]Tc-ADAPT6 and [(99)mTc]Tc-(HE)3-G3 distribution showed their high uptake in the kidneys and liver. Breast tumors were visualized in all cases. The average tumor uptake of [(99)mTc]Tc-ADAPT6 was 4.7 +/- 2.1, which was significantly higher than in the [(99)mTc]Tc-(HE)3-G3 injection (3.5 +/- 1.7) (p < 0.005, paired t-test). The tumor-to-background ratio (15.2 +/- 7.4 and 19.6 +/- 12.4, respectively) had no statistical differences in both cases (p > 0.05, paired t -test). Liver metastases were visualized in patients 1 and 5 and corresponded to the projection of metastases according to contrast-enhanced abdominal CT. The accumulation of [(99)mTc]Tc-ADAPT6 and [(99)mTc]Tc-(HE)3-G3 in the projection of metastases in both cases was significantly higher compared to the primary tumor (1.3 and 1.7 times higher in patient 1; 2.2 and 3.5 times higher in patient 5, respectively).Conclusion. Both [(99)mTc]Tc-ADAPT6 and [(99)mTc]Tc-(HE)3-G3 demonstrated the diagnostic efficacy in visualizing a primary HER2-positive tumor in breast cancer patients. However, [(99)mTc]Tc-ADEPT6 had higher accumulation values, which makes it a more promising diagnostic agent.
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| 10. |
- Bragina, O. D., et al.
(författare)
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Clinical possibilities of HER2-positive breast cancer diagnosis using alternative scaffold proteins
- 2022
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Ingår i: BYULLETEN SIBIRSKOY MEDITSINY. - : Siberian State Medical University. - 1682-0363 .- 1819-3684. ; 21:3, s. 132-139
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Tidskriftsartikel (refereegranskat)abstract
- HER2-positive breast cancer occurs in 15-20% of breast cancer patients and is associated primarily with a poor prognosis of the disease and the need for highly specific targeted therapy. Despite the clinical importance of determining HER2/neu, traditional diagnostic methods have their disadvantages and require the study of new additional research techniques. The information presented in this review makes it possible to consider current trends in the radionuclide diagnosis of HER2-positive breast cancer using the latest class of alternative scaffold proteins and to consider various aspects of their use in clinical practice.
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| 11. |
- Bragina, O. D., et al.
(författare)
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Possibilities of predicting the HER2 / neu status in a primary tumor in breast cancer patients using (99)mTc-DARPinG3
- 2022
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Ingår i: BYULLETEN SIBIRSKOY MEDITSINY. - : SIBERIAN STATE MEDICAL UNIV. - 1682-0363 .- 1819-3684. ; 21:4, s. 6-12
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To determine informative prognostic criteria for assessing the HER2 / neu status in primary breast cancer using 99mTc-DARPinG3.Materials and methods; The study included 10 patients with breast cancer (T1-4N0-2M0) before systemic therapy, who underwent a radionuclide study using 99mTc-DARPinG3 at a dose of 3,000 & mu;g. Five patients were characterized by HER2 / neu overexpression in primary breast cancer, whereas 5 patients were HER2-negative. For all patients, morphological and immunohistochemical studies and fluorescence in situ hybridization (FISH) of the primary tu-mor nodule were carried out. Single-photon emission computed tomography (SPECT) of the chest was performed for all patients 4 hours after the injection of 99mTc-DARPinG3.Results: The total activity of 99mTc-DARPinG3 was 522.4 & PLUSMN; 341.8 MBq. The comparative analysis showed that higher uptake of the labeled protein in HER2-positive breast cancer was significant (p = 0.0159, Mann - Whitney U test). The analysis of the ratios showed significant differences in the tumor-to-background ratios in patients with HER2-positive breast cancer (p < 0.0159, Mann - Whitney U test). Based on the logistic regression analysis, a mathematical model was developed to predict the status of HER2 / neu in primary breast cancer patients (specificity and sensitivity 100%; p = 0.0004) using 99mTc-DARPinG3 at a dose of 3,000 mcg 4 hours after the injection of the radiopharmaceutical.Conclusion: The results of the study allow to consider the tumor-to-background ratio 4 hours after the injection of 99mTc-DARPinG3 as an additional prognostic parameter for determining the HER2 / neu status in primary breast cancer.
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| 12. |
- Bragina, O. D., et al.
(författare)
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Possibilities of radionuclide diagnostics of Her2-positive breast cancer using technetium-99m-labeled target molecules : the first experience of clinical use
- 2021
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Ingår i: Bûlleten' sibirskoj mediciny. - : Siberian State Medical University. - 1682-0363 .- 1819-3684. ; 20:1, s. 23-30
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Tidskriftsartikel (refereegranskat)abstract
- Background. The main purpose of the Her2/neu status determination in clinical practice is to determine the indications for the appointment of targeted therapy. The main methods for detecting the Her2/neu status are the immunohistochemical method (IHC) and the fluorescence in situ hybridization (FISH); however, despite their widespread use, they have a number of significant disadvantages. Over the past few years, radionuclide diagnostics using a new class of alternative scaffold proteins that meet all the requirements for optimal delivery of radionuclides to tumor cells has become widespread.Aim. To study the possibility of clinical use of a radiopharmaceutical based on technetium-99m-labeled target molecules for the diagnosis of breast cancer with the Her2/neu overexpression in humans.Materials and methods. The study included 11 patients with breast cancer (T1–4N0–2M0) before systemic therapy: 5 with Her2/neu overexpression; expression of the marker was not detected in 6. In all cases, morphologicaland immunohistochemical studies were performed. In case of Her2/neu 2+, FISH analysis was performed. The radiopharmaceutical was prepared immediately before administration, after which it was slowly injected intravenously into the patient. Scintigraphic studies in the “WholeBody” mode and SPECT of the chest organs were performed 2, 4, 6 and 24 hours after injection.Results. Radiochemical yield, radiochemical purity and activity before administration were (80 ± 4)%, (98 ± 1)% and (434 ± 19.5) MBq, respectively. The greatest uptake by normal organs was observed at a time interval of 6 hours in the kidneys and at a moderate activity in the liver and lungs at the same time interval. The organ with the highest absorbed dose was the kidneys; significant accumulation was also detected in the adrenal glands, gallbladder, liver, pancreas and spleen. The smallest accu mulation of the studied drug was observed in the brain (0.001 ± 0.000) mGy and skin (0.001 ± 0.000) mGy. The effective dose was (0.009 ± 0.002) mGy. The difference between tumors with positive and negative Her2-neu expression was found at all time points. In this case, the best indicator was determined after 2 hours of drug injection (р < 0.05).Conclusion. Based on the results obtained, it can be indicated that the investigated radiopharmaceutical can be considered as a new additional method for the diagnosis of Her2-positive breast tumors.
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| 13. |
- Bragina, Olga D., et al.
(författare)
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The Evolution of Targeted Radionuclide Diagnosis of HER2-Positive Breast Cancer
- 2022
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Ingår i: ACTA NATURAE. - : RUSSIAN FEDERATION AGENCY SCIENCE & INNOVATION. - 2075-8251 .- 2075-8243. ; 14:2, s. 4-15
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Forskningsöversikt (refereegranskat)abstract
- This review examines the evolution of the radionuclide diagnosis of HER2-positive breast cancer using various compounds as a targeting module in clinical practice: from full-length antibodies to a new group of small synthetic proteins called alternative scaffold proteins. This topic is of especial relevance today in view of the problems attendant to the detection of breast cancer with HER2/neu overexpression, which, in most cases, introduce errors in the treatment of patients. The results of clinical studies of radiopharmaceuticals based on affibody molecules, ADAPTs, and DARPins for SPECT and PET have demonstrated good tolerability of the compounds, their rapid excretion from the body, and the possibility to differentiate tumor sites depending on the HER2/neu status. This indicates that targeted radionuclide diagnosis holds promise and the need to continue research in this direction.
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| 14. |
- Callaghan, Terry V., et al.
(författare)
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Arctic tundra and Polar Desert Ecosystems
- 2005
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Ingår i: Arctic Climate Impact Assessment. - 9780521865098 - 0521865093
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 15. |
- Moskalenko, R. A., et al.
(författare)
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Involvement of proinflammatory S100A9/A8 in the atherocalcinosis of aortic valves
- 2017
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Ingår i: Pathologia. - : Zaporizʹkyĭ derz͡havnyĭ medychnyĭ universytet. - 2306-8027. ; :1, s. 49-56
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Tidskriftsartikel (refereegranskat)abstract
- According to the results of the Euro-Heart Survey on Vascular Heart Disease the most common pathology is nonrheumatic aortic stenosis, it is also called as calcific aortic valve stenosis (CAVS), as in its pathogenesis the process of biomineralization of valve cusps and ring plays the main role. The aim of the work is the immunohistochemical study of mineralized tissue of aortic heart valves, which are affected by atherocalcinosis. Materials and methods. 30 samples of mineralized aortic valves (I group) and 10 samples of aortic valve without evidence of biomineralization (II group - control) were studied. Immunohistochemical study of expression of collagen (Collagen I), CD68, myeloperoxidase (MPO), calgranulin A (S100A8), calgranulin B (8100A9), caspase 3 (Casp 3) and osteopontin (OPN) was conducted in AV tissue of both groups. Results. In CAV tissues the fibrillar component (collagen I) growths was found, but the quantitative and qualitative compositions of CD68+ circulating inflammatory cells are not significantly different from the control group. CAVs contain much more MPO+-cells (p <0.001) in comparison to the group of AVs without biomineralization. Our data show a significant increase of the S100A9 and OPN expression in the mineralized tissue of AVs (p <0.01). Also, a higher expression level of Casp3 and MPO was found in CAVs (p <0.05). Comparing the first and the second groups of AVs connection between the expression of S100A8 was not determined. Conclusion. High Casp 3 expression confirms the increased level of cell elimination in the CAVs tissue, which is obviously connected with the impact of high local concentrations of S100A9. These facts can contribute to the development of pathological biomineralization of AV. Since osteopontin inhibits the hydroxyapatite formation by binding to the surface of the crystals, its hyperproduction is a counteracting factor against biomineralization in AV tissue.
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| 16. |
- Schönhense, G., et al.
(författare)
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Suppression of the vacuum space-charge effect in fs-photoemission by a retarding electrostatic front lens
- 2021
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Ingår i: Review of Scientific Instruments. - : American Institute of Physics (AIP). - 0034-6748 .- 1089-7623. ; 92:5
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Tidskriftsartikel (refereegranskat)abstract
- The performance of time-resolved photoemission experiments at fs-pulsed photon sources is ultimately limited by the e-e Coulomb interaction, downgrading energy and momentum resolution. Here, we present an approach to effectively suppress space-charge artifacts in momentum microscopes and photoemission microscopes. A retarding electrostatic field generated by a special objective lens repels slow electrons, retaining the k-image of the fast photoelectrons. The suppression of space-charge effects scales with the ratio of the photoelectron velocities of fast and slow electrons. Fields in the range from -20 to -1100 V/mm for E-kin = 100 eV to 4 keV direct secondaries and pump-induced slow electrons back to the sample surface. Ray tracing simulations reveal that this happens within the first 40 to 3 mu m above the sample surface for E-kin = 100 eV to 4 keV. An optimized front-lens design allows switching between the conventional accelerating and the new retarding mode. Time-resolved experiments at E-kin = 107 eV using fs extreme ultraviolet probe pulses from the free-electron laser FLASH reveal that the width of the Fermi edge increases by just 30 meV at an incident pump fluence of 22 mJ/cm(2) (retarding field -21 V/mm). For an accelerating field of +2 kV/mm and a pump fluence of only 5 mJ/cm(2), it increases by 0.5 eV (pump wavelength 1030 nm). At the given conditions, the suppression mode permits increasing the slow-electron yield by three to four orders of magnitude. The feasibility of the method at high energies is demonstrated without a pump beam at E-kin = 3830 eV using hard x rays from the storage ring PETRA III. The approach opens up a previously inaccessible regime of pump fluences for photoemission experiments.
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| 17. |
- Shmakov, A. G., et al.
(författare)
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Formation and consumption of NO in H-2 + O-2 + N-2 flames doped with NO or NH3 at atmospheric pressure
- 2010
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Ingår i: Combustion and Flame. - : Elsevier BV. - 0010-2180. ; 157:3, s. 556-565
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Tidskriftsartikel (refereegranskat)abstract
- Flat premixed burner-stabilized H-2 + O-2 + N-2 flames, neat or doped with 300-1000 ppm of NO or NH3, were studied experimentally using molecular-beam mass-spectrometry and simulated numerically. Spatial profiles of temperature and concentrations of stable species, H-2, O-2, H2O, NO, NH3, and of H and OH radicals obtained at atmospheric pressure in lean (phi = 0.47), near-stoichiometric (phi = 1.1) and rich (phi = 2.0) flames are reported. Good agreement between measured and calculated structure of lean and near-stoichiometric flames was found. Significant discrepancy between simulated and measured profiles of NO concentration was observed in the rich flames. Sensitivity and reaction path analyses revealed reactions responsible for the discrepancy. Modification to the model was proposed to improve an overall agreement with the experiment. (C) 2009 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
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| 18. |
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| 19. |
- Tolmachev, Vladimir, et al.
(författare)
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Targeted nuclear medicine. Seek and destroy
- 2022
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Ingår i: Russian Chemical Reviews. - : IOP Publishing. - 0036-021X .- 1468-4837. ; 91:3
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Forskningsöversikt (refereegranskat)abstract
- The targeted delivery of radionuclides to tumours holds great promise for diagnosis and treatment of malignant neoplasms. The development of scaffold proteins has significantly simplified the design of targeting agents with desirable properties. This review comprehensively describes the key aspects of the design of radionuclide compounds, including classification of radionuclides, methodology for their attachment to targeting agents and characteristics of these agents that affect their behaviour in the body. Various targeting molecules are compared in terms of their ability to specifically find malignant foci in the body. The most recent achievements of cancer theranostics that aim at increasing the selectivity of antitumour effect are described, such as the fusion of targeting scaffold proteins with the albumin-binding domain and pretargeting. Special attention is paid to the creation of targeted radionanomaterials. Advantages and disadvantages of different strategies are analyzed and approaches for improving the delivery to tumours and for minimizing the undesirable impact on healthy organs and tissues are proposed. Particular emphasis is placed on the results of studies published in 2020 ?? 2021 that have not yet been covered by reviews.
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