2023
Autores
Botelho, AR; Silva, HF; Martins, IS; Carneiro, IC; Carvalho, SD; Henrique, RM; Tuchin, VV; Oliveira, LM;
Publicação
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
Abstract
A fast calculation method was used to obtain the spectral optical properties of human normal and pathological (chromophobe renal cell carcinoma) kidney tissues. Using total transmittance, total reflectance and collimated transmittance spectra acquired from ex vivo kidney samples, the spectral optical properties of both tissues, namely the absorption, the scattering and the reduced scattering coefficients, as well as the scattering anisotropy, dispersion and light penetration depth, were calculated between 200 and 1000 nm. Analysis of the mean absorption coefficient spectra of the kidney tissues showed that both contain melanin and lipofuscin, and that 83 % of the melanin in the normal kidney converts into lipofuscin in the pathological kidney.
2023
Autores
Oliveira, LR; Ferreira, RM; Pinheiro, MR; Silva, HF; Tuchin, VV; Oliveira, LM;
Publicação
JOURNAL OF BIOPHOTONICS
Abstract
The increase of tissue transparency through sequential optical immersion clearing treatments and treatment reversibility have high interest for clinical applications. To evaluate the clearing reversibility in a broad spectral range and the magnitude of the transparency created by a second treatment, the present study consisted on measuring the spectral collimated transmittance of lung tissues during a sequence of two treatments with electronic cigarette (e-cig) fluid, which was intercalated with an immersion in saline. The saline immersion clearly reverted the clearing effect in the lung tissue in the spectral range between 220 and 1000 nm. By a later application of a second treatment with the e-cig fluid, the magnitude of the optical clearing effect was observed to be about the double as the one observed in the first treatment, showing that the molecules of the optical clearing agent might have converted some bound water into mobile water during the first treatment.
2023
Autores
Silva, HF; Martins, IS; Bogdanov, AA; Tuchin, VV; Oliveira, LM;
Publicação
JOURNAL OF BIOPHOTONICS
Abstract
The recent increasing interest in the application of radiology contrasting agents to create transparency in biological tissues implies that the diffusion properties of those agents need evaluation. The comparison of those properties with the ones obtained for other optical clearing agents allows to perform an optimized agent selection to create optimized transparency in clinical applications. In this study, the evaluation and comparison of the diffusion properties of gadobutrol and glycerol in skeletal muscle was made, showing that although gadobutrol has a higher molar mass than glycerol, its low viscosity allows for a faster diffusion in the muscle. The characterization of the tissue dehydration and refractive index matching mechanisms of optical clearing was made in skeletal muscle, namely by the estimation of the diffusion coefficients for water, glycerol and gadobutrol. The estimated tortuosity values of glycerol (2.2) and of gadobutrol (1.7) showed a longer path-length for glycerol in the muscle.
2023
Autores
Cunha, B; Ferreira, R; Melo, SC; Sousa, SP;
Publicação
Iberian Conference on Information Systems and Technologies, CISTI
Abstract
The Hoffmann reflex is a is a neurophysiological test that provides insight into the functioning of the human nervous system. It is commonly used in clinical and research settings to evaluate the modulation of the monosynaptic spinal reflex. This paper focus the analysis of the Hoffmann reflex in the trapezius muscle, a muscle of particular interest for researchers and clinicians due to its importance in upper limb function and dynamic stability. However, the Hoffmann reflex analysis of this muscle bring some challenges as the need of applicating burst of electrical square impulses in each current intensity. A web-based smart dashboard, implemented in Python, which allows the user to visualize and analyze the Hoffmann reflex using various signals acquired through a constant current stimulator. The dashboard provides an intuitive and user-friendly interface that facilitates the selection of muscle signals of interest, analysis cycles, and start and end points for the signals. The visualizations offered by the dashboard, including overlapped and mean signal graphics, provide valuable insights into the Hoffmann reflex and its properties. Preliminary experiments with field experts and physiotherapists have yielded positive feedback on the usefulness of this tool, as they seek to gain a deeper understanding of the Hoffmann reflex, and we plan to further improve its capabilities in the future by employing machine learning techniques to automate the reflex detection. © 2023 ITMA.
2023
Autores
Cunha, B; Ferreira, R; Sousa, ASP;
Publicação
SENSORS
Abstract
Advancements in modern medicine have bolstered the usage of home-based rehabilitation services for patients, particularly those recovering from diseases or conditions that necessitate a structured rehabilitation process. Understanding the technological factors that can influence the efficacy of home-based rehabilitation is crucial for optimizing patient outcomes. As technologies continue to evolve rapidly, it is imperative to document the current state of the art and elucidate the key features of the hardware and software employed in these rehabilitation systems. This narrative review aims to provide a summary of the modern technological trends and advancements in home-based shoulder rehabilitation scenarios. It specifically focuses on wearable devices, robots, exoskeletons, machine learning, virtual and augmented reality, and serious games. Through an in-depth analysis of existing literature and research, this review presents the state of the art in home-based rehabilitation systems, highlighting their strengths and limitations. Furthermore, this review proposes hypotheses and potential directions for future upgrades and enhancements in these technologies. By exploring the integration of these technologies into home-based rehabilitation, this review aims to shed light on the current landscape and offer insights into the future possibilities for improving patient outcomes and optimizing the effectiveness of home-based rehabilitation programs.
2023
Autores
Melo, ASC; Taylor, JL; Ferreira, R; Cunha, B; Ascencao, M; Fernandes, M; Sousa, V; Cruz, EB; Vilas-Boas, JP; Sousa, ASP;
Publicação
SENSORS
Abstract
In chronic shoulder pain, adaptations in the nervous system such as in motoneuron excitability, could contribute to impairments in scapular muscles, perpetuation and recurrence of pain and reduced improvements during rehabilitation. The present cross-sectional study aims to compare trapezius neural excitability between symptomatic and asymptomatic subjects. In 12 participants with chronic shoulder pain (symptomatic group) and 12 without shoulder pain (asymptomatic group), the H reflex was evoked in all trapezius muscle parts, through C3/4 nerve stimulation, and the M-wave through accessory nerve stimulation. The current intensity to evoke the maximum H reflex, the latency and the maximum peak-to-peak amplitude of both the H reflex and M-wave, as well as the ratio between these two variables, were calculated. The percentage of responses was considered. Overall, M-waves were elicited in most participants, while the H reflex was elicited only in 58-75% or in 42-58% of the asymptomatic and symptomatic participants, respectively. A comparison between groups revealed that the symptomatic group presented a smaller maximum H reflex as a percentage of M-wave from upper trapezius and longer maximal H reflex latency from the lower trapezius (p < 0.05). Subjects with chronic shoulder pain present changes in trapezius H reflex parameters, highlighting the need to consider trapezius neuromuscular control in these individuals' rehabilitation.
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