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1.
Front Sports Act Living ; 5: 1289140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116386

RESUMO

The purpose of this article is to adopt a customer-centric perspective the and introduce digital twin technology as a solution for mega-sport event management. This conceptual model article focuses on the potentially drastic role of digital twin technology in modern sports events, explaining in detail different aspects of its impact. The main research question is "How (and why) do sports venue digital twin emerging technologies prospectively impact the sports spectators" customer experiences?" It contributes to understanding how and why sports venue digital twins make events more customer-centred by enhancing fan experiences and engagement. Subsequently, it aims to position digital twin technology as an innovative solution for mega-sport event management across various customer experience touchpoints. By examining the intersection of digital twins and sports events from a customer-centric lens, this article will elucidate the intricacies involved in leveraging this emerging technology to transform stakeholder and fan experiences at major sporting events. Finally, we outline and explain the obstacles, challenges, opportunities, and perspectives of digital twin technology at an intersection with sports events from a customer-centric perspective. The use of digital twins potentially enables the creation of hyper-realistic virtual replicas of sports venues, providing immersive and personalized experiences for spectators. This technology allows event organizers to optimize resource allocation, streamline logistics, and improve operational efficiency.

2.
Int J Pharm ; 628: 122288, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36252644

RESUMO

Surface modification of magnetic nanoparticles with poly-l-lysine, proline, and tryptophan was used to design potential theranostic agents for the application in cancer diagnosis and radionuclide-hyperthermia therapy. Characterization of bare and functionalized magnetic nanoparticles was performed in detail. The transparency of the examined magnetic nanoparticles was measured in the non-alternating magnetic field for a complete and better understanding of hyperthermia. For the first time amino acid-functionalized magnetic nanoparticles were labeled with theranostic radionuclides 131I and 177Lu. The specific absorption rate (SAR) procured for poly-l-lysine functionalized magnetic nanoparticles (SAR values of 99.7 W/g at H0 = 15.9 kA/m and resonant frequency of 252 kHz) demonstrated their possible application in magnetic hyperthermia. Poly-l-lysine functionalized magnetic nanoparticles labeled with 177Lu showed the highest radiochemical purity (>99.00 %) and in vitro stability in saline and serum (>98.00 % up to 96 h). The in vivo analysis performed after their intravenous administration in healthy Wistar rats presented good in vivo stability for several days. Encouraging results as well as magnetic and radiochemical properties of 177Lu-PLL-MNPs (80 °C) justify their further testing toward the potential use as theranostic agents for diagnostic and combined radionuclide-hyperthermia therapeutic applications.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita , Animais , Ratos , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/química , Polilisina , Triptofano , Medicina de Precisão , Prolina , Ratos Wistar , Radioisótopos do Iodo
3.
Polymers (Basel) ; 14(9)2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35566987

RESUMO

The rise of innovation in the electrical industry is driven by the controlled design of new materials. The hybrid materials based on magnetite/nanocellulose are highly interesting due to their various applications in medicine, ecology, catalysis and electronics. In this study, the structure and morphology of nanocellulose/magnetite hybrid nanomaterials were investigated. The effect of nanocellulose loading on the crystal structure of synthesized composites was investigated by XRD and FTIR methods. The presented study reveals that the interaction between the cellulose and magnetic nanoparticles depends on the nanocellulose content. Further, a transition from cellulose II to cellulose I allomorph is observed. SEM and EDS are employed to determine the variation in morphology with changes in component concentrations. By the calculation of magnetic interactions between adjacent Fe3+ and Fe2+ ions within composites, it is determined that ferromagnetic coupling predominates.

4.
Int J Radiat Biol ; 97(12): 1687-1695, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34473599

RESUMO

PURPOSE: Recent studies with doxycycline as adjuvant therapy to conventional chemotherapy have shown promising results in cancer therapy. The current study aimed to examine the capability of 177Lu-labeled tetracycline ligand, doxycycline hyclate, to use as an anticancer agent. MATERIALS AND METHODS: Doxycycline was radiolabeled with beta-emitting radioisotope 177Lu. Complex formation and its interaction with DNA were investigated electrochemically. Binding of 177Lu-doxycycline to CT 26 cell line was done. Biodistribution of 177Lu-doxycycline was examined in healthy Wistar rats and CT26 colon carcinoma tumor-bearing mice by i.v. and i.p. administration, respectively. RESULTS: Doxycycline hyclate was successfully radiolabeled with 177Lu in high radiolabeling yield (>99%). The radiolabeled complex was stable in vitro in saline and human serum over 72 h. Non-radioactive Lu-doxycycline complex formation was demonstrated electrochemically as well. Intercalative interactions of the doxycycline and Lu-doxycycline with DNA were proved using simultaneously spectrophotometric and electrochemical methods. The binding of the radiolabeled complex with plasma proteins was 4.0 ± 0.4%. The partition coefficient showed the lipophilic nature of the complex similar to the free ligand. The binding curve demonstrates binding from 0.1 nM concentrations of 177Lu-doxycycline, with half-binding estimated ∼100 nM. Biodistribution studies of 177Lu-doxycycline in CT26 colon tumor-bearing mice showed a satisfactory accumulation rate in the tumor (2.88 ± 0.85% ID/g) 3 h after intraperitoneal injection. Both the hepatobiliary system and the urinary system were prominent as excretory routes of the radiolabeled complex. CONCLUSION: Considering obtained results, 177Lu-doxycycline complex, due to its excellent electrochemical and biological characteristics, with emphasis on the binding ability to DNA via intercalative interaction as well as significant accumulation in the tumor, is suitable for further in vivo studies to investigate its potential use in cancer treatment.


Assuntos
Doxiciclina , Lutécio , Compostos Radiofarmacêuticos , Animais , Linhagem Celular Tumoral , Ligantes , Camundongos , Ratos , Ratos Wistar , Distribuição Tecidual
5.
J Mater Chem B ; 5(44): 8738-8747, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-32264267

RESUMO

Radiolabeled magnetic nanoparticles (MNPs) coated with hydrophilic phosphate ligands, i.e., imidodiphosphate (IDP) and inositol hexaphosphate (IHP), were developed as multifunctional agents to localize both radioactivity and magnetic energy at a tumor site. The coating of MNPs with phosphates made them biocompatible, increased their colloidal stability and allowed binding of the radionuclide 90Y to the available functional groups on the surface of the MNPs. IDP and IHP have not hitherto been used for the coating of MNPs and the results of this study of the functionalized MNPs showed that the phosphate groups influenced the modification of the surface of MNPs. Characterization of the MNPs was performed using X-ray powder diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering and laser Doppler electrophoresis. The specific power absorption values obtained for MNPs (46.95-80.76 W g-1) in different physiological media indicated their possible application in hyperthermia treatment. Both types of coated MNPs were 90Y-labeled in a reproducible high yield (>98%). In vitro studies of 90Y-MNPs in saline and human serum showed their high stability after 72 h. The biodistribution pattern of the MNPs after intravenous administration to healthy Wistar rats was followed by the radiotracer method, revealing that 90Y-Fe3O4-IDP and 90Y-Fe3O4-IHP MNPs were predominantly found in the liver (85.21% ID and 86.22% ID), followed by the spleen (9.23% ID and 8.82% ID) and the lungs (1.53% ID and 1.53% ID). The results of this comprehensive study showed that radiolabeled biocompatible phosphate magnetic complexes hold great promise for therapeutic uses combining magnetic hyperthermia and radiotherapy.

6.
J Chem Phys ; 142(21): 214111, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-26049483

RESUMO

Herein, we present the systematic, comparative computational study of the d - d transitions in a series of first row transition metal hexaaqua complexes, [M(H2O)6](n+) (M(2+/3+) = V (2+/3+), Cr(2+/3+), Mn(2+/3+), Fe(2+/3+), Co(2+/3+), Ni(2+)) by the means of Time-dependent Density Functional Theory (TD-DFT) and Ligand Field Density Functional Theory (LF-DFT). Influence of various exchange-correlation (XC) approximations have been studied, and results have been compared to the experimental transition energies, as well as, to the previous high-level ab initio calculations. TD-DFT gives satisfactory results in the cases of d(2), d(4), and low-spin d(6) complexes, but fails in the cases when transitions depend only on the ligand field splitting, and for states with strong character of double excitation. LF-DFT, as a non-empirical approach to the ligand field theory, takes into account in a balanced way both dynamic and non-dynamic correlation effects and hence accurately describes the multiplets of transition metal complexes, even in difficult cases such as sextet-quartet splitting in d(5) complexes. Use of the XC functionals designed for the accurate description of the spin-state splitting, e.g., OPBE, OPBE0, or SSB-D, is found to be crucial for proper prediction of the spin-forbidden excitations by LF-DFT. It is shown that LF-DFT is a valuable alternative to both TD-DFT and ab initio methods.

7.
Chemistry ; 21(9): 3716-26, 2015 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-25591004

RESUMO

In this work we have analyzed in detail the magnetic anisotropy in a series of hydrotris(pyrazolyl)borate (Tp(-)) metal complexes, namely [VTpCl](+), [CrTpCl](+), [MnTpCl](+), [FeTpCl], [CoTpCl], and [NiTpCl], and their substituted methyl and tert-butyl analogues with the goal of observing the effect of the ligand field on the magnetic properties. In the [VTpCl](+), [CrTpCl](+), [CoTpCl], and [NiTpCl] complexes, the magnetic anisotropy arises as a consequence of out-of-state spin-orbit coupling, and covalent changes induced by the substitution of hydrogen atoms on the pyrazolyl rings does not lead to drastic changes in the magnetic anisotropy. On the other hand, much larger magnetic anisotropies were predicted in complexes displaying a degenerate ground state, namely [MnTpCl](+) and [FeTpCl], due to in-state spin-orbit coupling. The anisotropy in these systems was shown to be very sensitive to perturbations, for example, chemical substitution and distortions due to the Jahn-Teller effect. We found that by substituting the hydrogen atoms in [MnTpCl](+) and [FeTpCl] by methyl and tert-butyl groups, certain covalent contributions to the magnetic anisotropy energy (MAE) could be controlled, thereby achieving higher values. Moreover, we showed that the selection of ion has important consequences for the symmetry of the ground spin-orbit term, opening the possibility of achieving zero magnetic tunneling even in non-Kramers ions. We have also shown that substitution may also contribute to a quenching of the Jahn-Teller effect, which could significantly reduce the magnetic anisotropy of the complexes studied.

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