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BODIPYs have a well-established role in biological sciences as chemosensors and versatile biological markers due to their chemical reactivity, which allows for fine-tuning of their photophysical characteristics. In this work, we combined the unique reactivity of arylazo sulfones with the advantages of a "sunflow" reactor to develop a fast, efficient, and versatile method for the photochemical arylation of BODIPYs and other chromophores. This approach resulted in red-shifted emitting fluorophores due to extended electronic delocalization at the 3- and 5-positions of the BODIPY core. This method represents an advantageous approach for BODIPY functionalization compared to existing strategies.
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Significance: Continuous-wave functional near-infrared spectroscopy has proved to be a valuable tool for assessing hemodynamic activity in the human brain in a non-invasively and inexpensive way. However, most of the current processing/analysis methods assume the head is a homogeneous medium, and hence do not appropriately correct for the signal coming from the scalp. This effect can be reduced by considering light propagation in a layered model of the human head, being the Monte Carlo (MC) simulations the gold standard to this end. However, this implies large computation times and demanding hardware capabilities. Aim: In this work, we study the feasibility of replacing the homogeneous model and the MC simulations by means of analytical multilayered models, combining in this way, the speed and simplicity of implementation of the former with the robustness and accuracy of the latter. Approach: Oxy- and deoxyhemoglobin (HbO and HbR, respectively) concentration changes were proposed in two different layers of a magnetic resonance imaging (MRI)-based meshed model of the human head, and then these changes were retrieved by means of (i) a typical homogeneous reconstruction and (ii) a theoretical layered reconstruction. Results: Results suggest that the use of analytical models of light propagation in layered models outperforms the results obtained using traditional homogeneous reconstruction algorithms, providing much more accurate results for both, the extra- and the cerebral tissues. We also compare the analytical layered reconstruction with MC-based reconstructions, achieving similar degrees of accuracy, especially in the gray matter layer, but much faster (between 4 and 5 orders of magnitude). Conclusions: We have successfully developed, implemented, and validated a method for retrieving chromophore concentration changes in the human brain, combining the simplicity and speed of the traditional homogeneous reconstruction algorithms with robustness and accuracy much more similar to those provided by MC simulations.
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Encéfalo , Fótons , Humanos , Simulação por Computador , Encéfalo/diagnóstico por imagem , Couro Cabeludo/diagnóstico por imagem , Algoritmos , Imageamento por Ressonância Magnética , Método de Monte Carlo , Imagens de FantasmasRESUMO
The synthesis of the new dye 1,6-methano[10]annulenecyanine is described. For this purpose, the 3,4-dicyano-1,6-methano[10]annulene and 3,4-carboxyimide-1,6-methano[10]annulene buildings blocks were synthesized in six to eight steps. In both cases, these building blocks were then cyclotetramerized to furnish a new Zn(II)-1,6-methano[10]annulenecyanine which presents a strong red-shifted absorption band at 800 nm and high solubility in common organic solvents.
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Corantes Fluorescentes/síntese química , Compostos Organometálicos/síntese química , Corantes Fluorescentes/química , Estrutura Molecular , Compostos Organometálicos/química , SolubilidadeRESUMO
This paper presents the synthesis and characterization of two series of new bis-quinolin curcuminoid BF2-complexes 11 and their respective decomplexed bis-quinolin curcuminoid derivatives 12, in an attempt to understand their optical properties. The synthesized compounds showed interesting fluorescent characteristics in both solution and in solid-state. The characteristic of the electronic transitions involved in these systems were measured via Uv-vis spectroscopy and fluorescence spectroscopy. Results revealed that the absorption and emission bands are dependent of the structure of compounds 11 and 12 but also of the type of substituent, even showing a push-pull behavior in those derivatives substituted with methyl group. These findings were also confirmed through computational calculations at DFT level via simulations of the Uv-vis spectra and determining the topology of the border orbitals responsible for light absorption.
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ABSTRACT Fibroma is currently considered the most common reactive hyperplasia of fibrous connective tissue in response to local trauma in the oral cavity. This case deals with the excision of a traumatic fibroma using diode laser (Epic X, wavelength of 940nm, continuous mode, 5W power), whose energy is absorbed by hemoglobin and melanin (chromophores) and is indicated in soft tissue surgeries, favoring coagulation. The results are consistent with the benefits demonstrated in the scientific literature: better visibility in the surgical act due to achieved hemostasis, excellent postoperative phase due to the absence of pain and inflammation, with no need for analgesic medication, no use of sutures, no scarring and no recurrence. It is a safe and fast procedure that also allows performing a histopathological study without altering the tissues to be examined. In the case presented here, the histopathological study confirmed the presumptive diagnosis of fibroma.
RESUMEN El fibroma es considerado actualmente como la más común hiperplasia reactiva de tejido conectivo fibroso en respuesta a un trauma local en la cavidad bucal. En este caso se menciona la escisión de un fibroma traumático utilizando laser de diodo (Epic X, longitud de onda de 940nm, modo continuo, potencia 5W), cuya energía es absorbida por la hemoglobina y la melanina (cromóforos), indicado en cirugías de tejidos blandos, favoreciendo la coagulación. Los resultados están acordes con los beneficios demostrados en la literatura científica: mejor visibilidad en el acto quirúrgico por la hemostasia lograda, postoperatorio excelente por la ausencia de dolor e inflamación, sin necesidad de medicación analgésica ni uso de suturas, no produce aparición de cicatriz y no recidiva; ofrece seguridad y rapidez en el procedimiento. Permite la realización de estudio histopatológico sin alterar los tejidos a examinar. En el caso presentado, el estudio histopatológico comprobó el diagnóstico presuntivo de fibroma.
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Hiperplasia , Fibroma , LasersRESUMO
In this Letter, we explored the use of polarized two-photon absorption (2PA) spectroscopy, which brings additional information when compared to methods that do not use polarization control, to investigate the electronic and molecular structure of two chromophores (FD43 and FD48) based on phenylacetylene moieties. The results were analyzed using quantum chemical calculations of the two-photon transition strengths for circularly and linearly polarized light, provided by the response function formalism. On the basis of these data, it was possible to distinguish and identify the excited electronic states responsible for the lowest-energy 2PA-allowed band in both chromophores. By modeling the 2PA circular-linear dichroism, within the sum-over-essential states approach, we obtained the relative orientation between the dipole moments that are associated with the molecular structure of the chromophores in solution. This result allowed to correlate the V-shape structure of the FD48 chromophore and the quantum-interference-modulated 2PA strength.