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1.
Sensors (Basel) ; 23(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36850483

RESUMO

This paper presents a critical review and comparison of the results of recently published studies in the fields of human-machine interface and the use of sonomyography (SMG) for the control of upper limb prothesis. For this review paper, a combination of the keywords "Human Machine Interface", "Sonomyography", "Ultrasound", "Upper Limb Prosthesis", "Artificial Intelligence", and "Non-Invasive Sensors" was used to search for articles on Google Scholar and PubMed. Sixty-one articles were found, of which fifty-nine were used in this review. For a comparison of the different ultrasound modes, feature extraction methods, and machine learning algorithms, 16 articles were used. Various modes of ultrasound devices for prosthetic control, various machine learning algorithms for classifying different hand gestures, and various feature extraction methods for increasing the accuracy of artificial intelligence used in their controlling systems are reviewed in this article. The results of the review article show that ultrasound sensing has the potential to be used as a viable human-machine interface in order to control bionic hands with multiple degrees of freedom. Moreover, different hand gestures can be classified by different machine learning algorithms trained with extracted features from collected data with an accuracy of around 95%.


Assuntos
Membros Artificiais , Humanos , Algoritmos , Inteligência Artificial , Biônica , Coleta de Dados
2.
J Clin Ultrasound ; 51(7): 1212-1222, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37334435

RESUMO

AIMS: To investigate the reliability, validity, and level of evidence of applying ultrasound in assessing the lower-limb muscles of patients with cerebral palsy (CP). METHOD: Publications in Medline, PubMed, Web of Science, and Embase were searched on May 10, 2023, to identify and examine relevant studies investigating the reliability/validity of ultrasound in evaluating the architecture of CP lower-limb muscles systematically, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 guidelines. RESULTS: Out of 897 records, 9 publications with 111 CP participants aged 3.8-17.0 years were included (8 focused on intra-rater and inter-rater reliability, 2 focused on validity, and 4 were with high quality). The ultrasound-based measurements of muscle thickness (intra-rater only), muscle length, cross-sectional area, muscle volume, fascicle length, and pennation angle showed high reliability, with the majority of intraclass correlation coefficient (ICC) values being larger than 0.9. Moderate-to-good correlations between ultrasound and magnetic resonance imaging measurements existed in muscle thickness and cross-sectional area (0.62 ≤ ICC ≤ 0.82). INTERPRETATION: Generally, ultrasound has high reliability and validity in evaluating the CP muscle architecture, but this is mainly supported by moderate and limited levels of evidence. More high-quality future studies are needed.


Assuntos
Paralisia Cerebral , Humanos , Paralisia Cerebral/diagnóstico por imagem , Reprodutibilidade dos Testes , Músculo Esquelético/diagnóstico por imagem , Extremidade Inferior/diagnóstico por imagem , Ultrassonografia/métodos
3.
Adv Exp Med Biol ; 1364: 349-372, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35508883

RESUMO

In recent years, the amount of publications related to the study of spine using ultrasound, especially on scoliosis, has rapidly increased. Many new methods and application related to 3D ultrasound imaging for scoliosis assessment have been recently reported. The capabilities of three-dimensional (3D) ultrasound to visualize the vertebrae features such as spinous and transverse processes, bilateral laminae and ribs mainly at the level of main thoracic and thoracolumbar region are shown in this chapter. Different ultrasound systems developed for scoliosis evaluation and application of ultrasound during different postures and treatments such as brace fitting are also introduced. Moreover, innovative measurement methods for spinal evaluation in orthogonal planes are presented in this chapter. The advance of the development of 3D ultrasound allows one to perform large-scale screening, prognosticate and diagnose mild and severe scoliosis at a more frequent and non-ionizing basis. The authors wish that this chapter will help to promote the applications of ultrasound to medical specialists in different aspects regarding the possibilities of ultrasonography to tackle with different spinal problems.


Assuntos
Escoliose , Humanos , Imageamento Tridimensional/métodos , Postura , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Ultrassonografia
4.
J Ultrasound Med ; 41(3): 547-563, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33949710

RESUMO

Low-intensity pulsed ultrasound (LIPUS) is a developing technology, which has been proven to improve fracture healing process with minimal thermal effects. This noninvasive treatment accelerates bone formation through various molecular, biological, and biomechanical interactions with tissues and cells. Although LIPUS treatment has shown beneficial effects on different bone fracture locations, only very few studies have examined its effects on deeper bones. This study provides an overview on therapeutic ultrasound for fractured bones, possible mechanisms of action, clinical evidences, current limitations, and its future prospects.


Assuntos
Fraturas Ósseas , Terapia por Ultrassom , Osso e Ossos , Consolidação da Fratura , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/terapia , Humanos , Ondas Ultrassônicas
5.
Sensors (Basel) ; 22(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35632054

RESUMO

Slip-induced falls, responsible for approximately 40% of falls, can lead to severe injuries and in extreme cases, death. A large foot-floor contact angle (FFCA) during the heel-strike event has been associated with an increased risk of slip-induced falls. The goals of this feasibility study were to design and assess a method for detecting FFCA and providing cues to the user to generate a compensatory FFCA response during a future heel-strike event. The long-term goal of this research is to train gait in order to minimize the likelihood of a slip event due to a large FFCA. An inertial measurement unit (IMU) was used to estimate FFCA, and a speaker provided auditory semi-real-time feedback when the FFCA was outside of a 10-20 degree target range following a heel-strike event. In addition to training with the FFCA feedback during a 10-min treadmill training period, the healthy young participants completed pre- and post-training overground walking trials. Results showed that training with FFCA feedback increased FFCA events within the target range by 16% for "high-risk" walkers (i.e., participants that walked with more than 75% of their FFCAs outside the target range) both during feedback treadmill trials and post-training overground trials without feedback, supporting the feasibility of training FFCA using a semi-real-time FFCA feedback system.


Assuntos
Acidentes por Quedas , Marcha , Acidentes por Quedas/prevenção & controle , Fenômenos Biomecânicos , Estudos de Viabilidade , Retroalimentação , Marcha/fisiologia , Humanos
6.
J Strength Cond Res ; 36(4): 941-947, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35319000

RESUMO

ABSTRACT: Huang, Z-H, Ma, CZ-H, Wang, L-K, Wang, X-Y, Fu, S-N, and Zheng, Y-P. Real-time visual biofeedback via wearable ultrasound imaging can enhance the muscle contraction training outcome of young adults. J Strength Cond Res 36(4): 941-947, 2022-Real-time ultrasound imaging (RUSI) can serve as visual biofeedback to train deep muscle contraction in clinical rehabilitative settings. However, its effectiveness in resistance training in sports/fitness fields remains unexplored. This article introduced a newly developed wearable RUSI system that provided visual biofeedback of muscle thickening and movement and reported its effectiveness in improving the training outcomes of muscle thickness change (%) during dynamic contraction. Twenty-five healthy young men participated and performed pec fly exercise both with and without RUSI biofeedback. Statistical analysis was conducted to examine the reliability of the measurements and the immediate effects of (a) RUSI biofeedback of muscle contraction and (b) training intensity (50 vs. 80% of 1-repetition maximum [1RM]) on the pectoralis major (PMaj) thickness change measured by ultrasound images. In addition to significantly high inter-contraction reliability (ICC3,1 > 0.97), we observed significantly increased PMaj thickness change for both training intensities upon receiving biofeedback in subjects, compared with without biofeedback (p < 0.001). We also observed significantly larger PMaj thickness change at 80% of 1RM compared with 50% of 1RM (p = 0.023). The provision of visual biofeedback using RUSI significantly enlarged the magnitude of PMaj thickness change during pec fly exercises, potentially indicating that RUSI biofeedback could improve the ability of targeted muscle contraction of PMaj in healthy young adults. To our knowledge, this study has pioneered in applying RUSI as a form of biofeedback during weight training and observed positive effectiveness. Future iterations of the technique will benefit more subject groups, such as athletes and patients with neuromuscular disorders.


Assuntos
Contração Muscular , Dispositivos Eletrônicos Vestíveis , Biorretroalimentação Psicológica , Humanos , Contração Muscular/fisiologia , Reprodutibilidade dos Testes , Ultrassonografia/métodos , Adulto Jovem
7.
Biophys J ; 120(16): 3498-3507, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34022236

RESUMO

Myopia is a common ocular disorder with significant alterations in the anterior ocular structure, including the cornea. The cell biophysical phenotype has been proposed to reflect the state of various diseases. However, the biophysical properties of corneal cells have not been characterized during myopia progression and their relationship with myopia remains unknown. This study characterizes the biophysical properties of corneal cells in normal, myopic, and recovered conditions, using two classical myopia models. Surprisingly, myopic corneal cells considerably reduce F-actin and microtubule content and cellular stiffness and generate elevated traction force compared with control cells. When myopia is restored to the healthy state, these biophysical properties are partially or fully restored to the levels of control cells. Furthermore, the level of chromatin condensation is significantly increased in the nucleus of myopic corneal cells and reduced to a level similar to healthy cells after recovery. These findings demonstrate that the reversible biophysical alterations of corneal cells reflect myopia progression, facilitating the study of the role of corneal cell biophysics in myopia.


Assuntos
Miopia , Biofísica , Córnea , Progressão da Doença , Humanos , Refração Ocular
8.
Eur Spine J ; 30(3): 628-633, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33156440

RESUMO

PURPOSE: Adolescent idiopathic scoliosis (AIS) patients are exposed to 9-10 times more radiation and a fivefold increased lifetime cancer risk. Radiation-free imaging alternatives are needed. Ultrasound imaging of spinal curvature was shown to be accurate, however, systematically underestimating the Cobb angle. The purpose of this study is to create and cross-validate an equation that calculates the expected Cobb angle using ultrasound spinal measurements of AIS patients. METHODS: Seventy AIS patients with upright radiography and spinal ultrasound were split randomly in a 4:1 ratio to the equation creation (n = 54) or validation (n = 16) group. Ultrasound angles based on the spinous processes shadows were measured automatically by the ultrasound system (Scolioscan, Telefield, Hong Kong). For thoracic and lumbar curves separately, the equation: expected Cobb angle = regression coefficient × ultrasound angle, was created and subsequently cross-validated in the validation group. RESULTS: Linear regression analysis between ultrasound angles and radiographic Cobb angles (thoracic: R2 = 0.968, lumbar: R2 = 0.923, p < 0.001) in the creation group resulted in the equations: thoracic Cobb angle = 1.43 × ultrasound angle and lumbar Cobb angle = 1.23 × ultrasound angle. With these equations, expected Cobb angles in the validation group were calculated and showed an excellent correlation with the radiographic Cobb angles (thoracic: R2 = 0.959, lumbar: R2 = 0.936, p < 0.001). The mean absolute differences were 6.5°-7.3°. Bland-Altman plots showed good accuracy and no proportional bias. CONCLUSION: The equations from ultrasound measurements to Cobb angles were valid and accurate. This supports the implementation of ultrasound imaging, possibly leading to less frequent radiography and reducing ionizing radiation in AIS patients.


Assuntos
Cifose , Escoliose , Adolescente , Hong Kong , Humanos , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Ultrassonografia
9.
Dysphagia ; 36(4): 650-658, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32889626

RESUMO

This study aimed to investigate the application of ultrasound to the learning of swallowing maneuver. Forty non-dysphagic adults of both genders who were naïve to the Mendelsohn maneuver participated in the study. They were randomly assigned to receive ultrasound or surface electromyography (sEMG) as biofeedback when acquiring the Mendelsohn maneuver. Thirty-eight subjects (n = 19) completed the Learning phase. Accuracy of executing the Mendelsohn maneuver was measured immediately (Post-training percentage accuracy) and one week post-training (Retention percentage accuracy). Whereas comparable numbers of training blocks were completed by the two groups (t(31.51) = 3.68, p = 0.330), the Ultrasound group attained significantly higher percentage accuracies than the sEMG group at both Post-training (t(28.88) = 4.04, p < 0.001, d = 1.309) and Retention (t(30.78) = 2.13, p = 0.042, d = 0.690). Ultrasound is a more effective biofeedback than sEMG in the acquisition of the Mendelsohn maneuver and may be adopted to the rehabilitative treatment for dysphagic individuals. Non-specificity of sEMG as biofeedback should be emphasized when it is employed in the training and learning of swallowing maneuvers. Findings from the present study suggest that ultrasound is preferable to sEMG as biofeedback in the learning of the Mendelsohn maneuver.


Assuntos
Transtornos de Deglutição , Adulto , Biorretroalimentação Psicológica , Deglutição , Eletromiografia , Feminino , Humanos , Masculino , Projetos Piloto
10.
Sensors (Basel) ; 21(19)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34640913

RESUMO

Transcutaneous electrical spinal cord stimulation (tSCS) is a non-invasive neuromodulatory technique that has in recent years been linked to improved volitional limb control in spinal-cord injured individuals. Although the technique is growing in popularity there is still uncertainty regarding the neural mechanisms underpinning sensory and motor recovery. Brain monitoring techniques such as electroencephalography (EEG) may provide further insights to the changes in coritcospinal excitability that have already been demonstrated using other techniques. It is unknown, however, whether intelligible EEG can be extracted while tSCS is being applied, owing to substantial high-amplitude artifacts associated with stimulation-based therapies. Here, for the first time, we characterise the artifacts that manifest in EEG when recorded simultaneously with tSCS. We recorded multi-channel EEG from 21 healthy volunteers as they took part in a resting state and movement task across two sessions: One with tSCS delivered to the cervical region of the neck, and one without tSCS. An offline analysis in the time and frequency domain showed that tSCS manifested as narrow, high-amplitude peaks with a spectral density contained at the stimulation frequency. We quantified the altered signals with descriptive statistics-kurtosis, root-mean-square, complexity, and zero crossings-and applied artifact-suppression techniques-superposition of moving averages, adaptive, median, and notch filtering-to explore whether the effects of tSCS could be suppressed. We found that the superposition of moving averages filter was the most successful technique at returning contaminated EEG to levels statistically similar to that of normal EEG. In the frequency domain, however, notch filtering was more effective at reducing the spectral power contribution of stimulation from frontal and central electrodes. An adaptive filter was more appropriate for channels closer to the stimulation site. Lastly, we found that tSCS posed no detriment the binary classification of upper-limb movements from sensorimotor rhythms, and that adaptive filtering resulted in poorer classification performance. Overall, we showed that, depending on the analysis, EEG monitoring during transcutaneous electrical spinal cord stimulation is feasible. This study supports future investigations using EEG to study the activity of the sensorimotor cortex during tSCS, and potentially paves the way to brain-computer interfaces operating in the presence of spinal stimulation.


Assuntos
Traumatismos da Medula Espinal , Estimulação da Medula Espinal , Eletroencefalografia , Humanos , Músculo Esquelético
11.
Sensors (Basel) ; 21(20)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34696113

RESUMO

Millions of individuals suffer from upper extremity paralysis caused by neurological disorders including stroke, traumatic brain injury, or spinal cord injury. Robotic hand exoskeletons can substitute the missing motor control and help restore the functions in daily operations. However, most of the hand exoskeletons are bulky, stationary, and cumbersome to use. We have modified a recent existing design (Tenoexo) to prototype a motorized, lightweight, fully wearable rehabilitative hand exoskeleton by combining rigid parts with a soft mechanism capable of producing various grasps needed for the execution of daily tasks. Mechanical evaluation of our exoskeleton showed that it can produce fingertip force up to 8 N and can cover 91.5° of range of motion in just 3 s. We further tested the performance of the developed robotic exoskeleton in two quadriplegics with chronic hand paralysis and observed immediate success on independent grasping of different daily objects. The results suggested that our exoskeleton is a viable option for hand function assistance, allowing patients to regain lost finger control for everyday activities.


Assuntos
Exoesqueleto Energizado , Mãos , Força da Mão , Humanos , Paralisia , Amplitude de Movimento Articular
12.
Sensors (Basel) ; 21(8)2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921592

RESUMO

To diagnose scoliosis, the standing radiograph with Cobb's method is the gold standard for clinical practice. Recently, three-dimensional (3D) ultrasound imaging, which is radiation-free and inexpensive, has been demonstrated to be reliable for the assessment of scoliosis and validated by several groups. A portable 3D ultrasound system for scoliosis assessment is very much demanded, as it can further extend its potential applications for scoliosis screening, diagnosis, monitoring, treatment outcome measurement, and progress prediction. The aim of this study was to investigate the reliability of a newly developed portable 3D ultrasound imaging system, Scolioscan Air, for scoliosis assessment using coronal images it generated. The system was comprised of a handheld probe and tablet PC linking with a USB cable, and the probe further included a palm-sized ultrasound module together with a low-profile optical spatial sensor. A plastic phantom with three different angle structures built-in was used to evaluate the accuracy of measurement by positioning in 10 different orientations. Then, 19 volunteers with scoliosis (13F and 6M; Age: 13.6 ± 3.2 years) with different severity of scoliosis were assessed. Each subject underwent scanning by a commercially available 3D ultrasound imaging system, Scolioscan, and the portable 3D ultrasound imaging system, with the same posture on the same date. The spinal process angles (SPA) were measured in the coronal images formed by both systems and compared with each other. The angle phantom measurement showed the measured angles well agreed with the designed values, 59.7 ± 2.9 vs. 60 degrees, 40.8 ± 1.9 vs. 40 degrees, and 20.9 ± 2.1 vs. 20 degrees. For the subject tests, results demonstrated that there was a very good agreement between the angles obtained by the two systems, with a strong correlation (R2 = 0.78) for the 29 curves measured. The absolute difference between the two data sets was 2.9 ± 1.8 degrees. In addition, there was a small mean difference of 1.2 degrees, and the differences were symmetrically distributed around the mean difference according to the Bland-Altman test. Scolioscan Air was sufficiently comparable to Scolioscan in scoliosis assessment, overcoming the space limitation of Scolioscan and thus providing wider applications. Further studies involving a larger number of subjects are worthwhile to demonstrate its potential clinical values for the management of scoliosis.


Assuntos
Escoliose , Adolescente , Criança , Humanos , Imageamento Tridimensional , Reprodutibilidade dos Testes , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Ultrassonografia
13.
Sensors (Basel) ; 21(3)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498590

RESUMO

Wandering is a common behavioral disorder in the community-dwelling elderly. More than two-thirds of caregivers believe that wandering would cause falls. While physical restraint is a common measure to address wandering, it could trigger challenging behavior in approximately 80% of the elderly with dementia. This study aims to develop a virtual restraint using a night monitoring system (eNightLog) to provide a safe environment for the elderly and mitigate the caregiver burden. The eNightLog system consisted of remote sensors, including a near infra-red 3D time-of-flight sensor and ultrawideband sensors. An alarm system was controlled by customized software and algorithm based on the respiration rate and body posture of the elderly. The performance of the eNightLog system was evaluated in both single and double bed settings by comparing to that of a pressure mat and an infrared fence system, under simulated bed-exiting scenarios. The accuracy and precision for the three systems were 99.0%, 98.8%, 85.9% and 99.2%, 97.8%, 78.6%, respectively. With higher accuracy, precision, and a lower false alarm rate, eNightLog demonstrated its potential as an alternative to physical restraint to remedy the workload of the caregivers and the psychological impact of the elderly.


Assuntos
Monitorização Fisiológica , Comportamento Errante , Acidentes por Quedas , Idoso , Cuidadores , Humanos , Vida Independente
14.
Brain Inj ; 34(13-14): 1771-1780, 2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264033

RESUMO

Objectives: To investigate the effects of transcutaneous electrical stimulation (tES) on upper limb functional rehabilitation in a patient with traumatic brain injury (TBI), and to identify the optimum stimulation parameters of tES. Design: A preliminary case study. Methods: Two successive interventions: Phase I-voluntary physical training (vPT) and Phase II - tES along with vPT (tES+vPT). tES was delivered at C3 and C6 cervical regions. Clinical assessments presented the variation of muscle tone and motor functions, before and after each training phase, and evaluated at 1-month follow up after the last intervention. Results: Our results indicate that vPT alone contributed to a release of muscle spasticity of both arms of the patient with no significant improvement of hand function, while tES+vPT further reduced the spasticity of the left arm, and improved the voluntary motor function of both arms. The grip forces were also increased after the tES+vPT treatment. We found that 1 ms biphasic tES at 30 Hz produced optimum motor outputs. Conclusion: The study demonstrates, for the first time, the potential benefits of cervical tES in regard to improving upper limb motor functions in a patient with chronic TBI.


Assuntos
Lesões Encefálicas Traumáticas , Medula Cervical , Traumatismos da Medula Espinal , Braço , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/terapia , Mãos , Humanos , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/terapia
15.
Sensors (Basel) ; 20(19)2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993105

RESUMO

BACKGROUND: Available methods for studying muscle dynamics, including electromyography (EMG), mechanomyography (MMG) and M-mode ultrasound, have limitations in terms of spatial resolution. METHODS: This study developed a novel method/protocol of two-dimensional mapping of muscle motion onset using ultrafast ultrasound imaging, i.e., sono-mechano-myo-graphy (SMMG). The developed method was compared with the EMG, MMG and force outputs of tibialis anterior (TA) muscle during ankle dorsiflexion at different percentages of maximum voluntary contraction (MVC) force in healthy young adults. RESULTS: Significant differences between all pairwise comparisons of onsets were identified, except between SMMG and MMG. The EMG onset significantly led SMMG, MMG and force onsets by 40.0 ± 1.7 ms (p < 0.001), 43.1 ± 5.2 ms (p < 0.005) and 73.0 ± 4.5 ms (p < 0.001), respectively. Muscle motion also started earlier at the middle aponeurosis than skin surface and deeper regions when viewed longitudinally (p < 0.001). No significant effect of force level on onset delay was found. CONCLUSIONS: This study introduced and evaluated a new method/protocol, SMMG, for studying muscle dynamics and demonstrated its feasibility for muscle contraction onset research. This novel technology can potentially provide new insights for future studies of neuromuscular diseases, such as multiple sclerosis and muscular dystrophy.


Assuntos
Contração Isométrica , Contração Muscular , Músculo Esquelético , Miografia/métodos , Ultrassonografia , Eletromiografia , Humanos , Músculo Esquelético/diagnóstico por imagem , Adulto Jovem
16.
Sensors (Basel) ; 20(24)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352767

RESUMO

Muscle stiffness in the spinal region is essential for maintaining spinal function, and might be related to multiple spinal musculoskeletal disorders. However, information on the distribution of muscle stiffness along the spine in different postures in large subject samples has been lacking, which merits further investigation. This study introduced a new protocol of measuring bilateral back muscle stiffness along the thoracic and lumbar spine (at T3, T7, T11, L1 & L4 levels) with both ultrasound shear-wave elastography (SWE) and tissue ultrasound palpation system (TUPS) in the lying and standing postures of 64 healthy adults. Good inter-/intra-reliability existed in the SWE and TUPS back muscle stiffness measurements (ICC ≥ 0.731, p < 0.05). Back muscle stiffness at the L4 level was found to be the largest in the thoracic and lumbar regions (p < 0.05). The back muscle stiffness of males was significantly larger than that of females in both lying and standing postures (p < 0.03). SWE stiffness was found to be significantly larger in standing posture than lying among subjects (p < 0.001). It is reliable to apply SWE and TUPS to measure back muscle stiffness. The reported data on healthy young adults in this study may also serve as normative reference data for future studies on patients with scoliosis, low back pain, etc.


Assuntos
Músculos do Dorso , Técnicas de Imagem por Elasticidade , Ultrassonografia , Feminino , Humanos , Masculino , Músculos , Projetos Piloto , Reprodutibilidade dos Testes , Adulto Jovem
17.
J Neuroeng Rehabil ; 16(1): 36, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850027

RESUMO

BACKGROUND: Functional electrical stimulation (FES) is used to restore movements in paretic limbs after severe paralyses resulting from neurological injuries such as spinal cord injury (SCI). Most chronic FES systems utilize an implantable electrical stimulator to deliver a small electric current to the targeted muscle or nerve to stimulate muscle contractions. These implanted stimulators are generally bulky, mainly due to the size of the batteries. Furthermore, these battery-powered stimulators are required to be explanted every few years for battery replacement which may result in surgical failures or infections. Hence, a wireless power transfer technique is desirable to power these implantable stimulators. METHODS: Conventional wireless power transduction faces significant challenges for safe and efficient energy transfer through the skin and deep into the body. Inductive and electromagnetic power transduction is generally used for very short distances and may also interfere with other medical measurements such as X-ray and MRI. To address these issues, we have developed a wireless, ultrasonically powered, implantable piezoelectric stimulator. The stimulator is encapsulated with biocompatible materials. RESULTS: The stimulator is capable of harvesting a maximum of 5.95 mW electric power at an 8-mm depth under the skin from an ultrasound beam with about 380 mW/cm2 of acoustic intensity. The stimulator was implanted in several paraplegic rats with SCI. Our implanted stimulator successfully induced several hindlimb muscle contractions and restored leg movement. CONCLUSIONS: A battery-free miniature (10 mm diameter × 4 mm thickness) implantable stimulator, developed in the current study is capable of directly stimulating paretic muscles through external ultrasound signals. The required cost to develop the stimulator is relatively low as all the components are off the shelf.


Assuntos
Estimulação Elétrica/instrumentação , Próteses e Implantes , Tecnologia sem Fio/instrumentação , Animais , Estimulação Elétrica/métodos , Movimento/fisiologia , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/fisiopatologia
18.
Sensors (Basel) ; 19(1)2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30621103

RESUMO

BACKGROUND: Motion capture and analyzing systems are essential for understanding locomotion. However, the existing devices are too cumbersome and can be used indoors only. A newly-developed wearable motion capture and measurement system with multiple sensors and ultrasound imaging was introduced in this study. METHODS: In ten healthy participants, the changes in muscle area and activity of gastrocnemius, plantarflexion and dorsiflexion of right leg during walking were evaluated by the developed system and the Vicon system. The existence of significant changes in a gait cycle, comparison of the ankle kinetic data captured by the developed system and the Vicon system, and test-retest reliability (evaluated by the intraclass correlation coefficient, ICC) in each channel's data captured by the developed system were examined. RESULTS: Moderate to good test-retest reliability of various channels of the developed system (0.512 ≤ ICC ≤ 0.988, p < 0.05), significantly high correlation between the developed system and Vicon system in ankle joint angles (0.638R ≤ 0.707, p < 0.05), and significant changes in muscle activity of gastrocnemius during a gait cycle (p < 0.05) were found. CONCLUSION: A newly developed wearable motion capture and measurement system with ultrasound imaging that can accurately capture the motion of one leg was evaluated in this study, which paves the way towards real-time comprehensive evaluation of muscles and joint motions during different activities in both indoor and outdoor environments.


Assuntos
Locomoção/fisiologia , Músculo Esquelético/fisiologia , Caminhada/fisiologia , Dispositivos Eletrônicos Vestíveis , Adulto , Fenômenos Biomecânicos/fisiologia , Feminino , Marcha/fisiologia , Humanos , Masculino , Monitorização Fisiológica
19.
Ann Hepatol ; 17(3): 511-518, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29735802

RESUMO

INTRODUCTION AND AIM: Hepatitis C virus core-binding protein 6 (HCBP6) was previously found to be an hepatitis C virus corebinding protein, its biological function remains unclear. Our research aims to investigate the role of HCBP6 in the development of hepatic steatosis induced by high-fat diet and carbon tetrachloride (CCL4) in rats. MATERIAL AND METHODS: Eighteen Wistar rats were randomly allocated into 3 groups: control group, model group 1, and model group 2. The control group was treated with a standard diet for 5 weeks. Model groups were treated with high-fat diet and CCL4 injection twice a week for 3 weeks in Group 1 and 5 weeks in Group 2, respectively. After the intervention, hepatic steatosis was observed by histological staining with hematoxylin and eosin (H&E) and Oil Red O staining. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total colesterol (TC), and triglycerides (TGs) were measured. The TG content in liver homogenates was evaluated. Expressions of HCBP6 and SREBP-1c were determined by immunofluorescence, quantitative real-time PCR, and Western blot analysis. RESULTS: Hepatic steatosis was successfully induced in model groups. ALT, AST, TC, and TGs elevated in model groups compared with those in control group (P < 0.05). Hepatic steatosis induced by high-fat diet and CCL4 resulted in low expression of HCBP6 and high expression of SREBP-1c in the liver of rats (P < 0.05). CONCLUSION: HCBP6 is involved in the development of high-fat diet- and CCL4-induced hepatic steatosis and related negatively with SREBP-1c.


Assuntos
Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fatores de Ligação ao Core/metabolismo , Dieta Hiperlipídica , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colesterol/sangue , Fatores de Ligação ao Core/genética , Feminino , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos Wistar , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/sangue
20.
Eur Spine J ; 27(9): 2139-2147, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29943198

RESUMO

PURPOSE: The Adam's forward bending test is the most commonly used approach to assess the spine deformity in adolescent idiopathic scoliosis (AIS) patients. However, there are noticeable differences in the hump appearance from standing to forward bending. This phenomenon has yet to be understood due to limitations of conventional radiographs. This study aimed to investigate effects of postural change in the spine deformity in the coronal plane of AIS patients using a 3D ultrasound imaging system. METHODS: This was a prospective study that recruited 72 AIS patients at a single institute. All patients were scanned twice in the sitting and sitting forward bending postures. A coronal ultrasound image showing the spinal curvature was generated after each scan and the spinous process angle (SPA) representing the deformity was manually measured from it. Correlation of SPAs under sitting and sitting forward bending postures was analyzed. RESULTS: In the comparison test, it was noted that there were three types of spine profile alternation after the postural change. In types I and II, the SPA angle numbers were the same before and after forward bending and only SPA values changed. In type III, the two curvatures were changed to one curvature in the forward bending posture. Moderate correlation was observed between the angles obtained in the two postures (r = 0.55, p < 0.001). CONCLUSIONS: Spine deformities of AIS patients vary with different postures. The patterns of changes in sitting and sitting forward bending postures are highly subject dependent. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Escoliose/diagnóstico por imagem , Adolescente , Feminino , Humanos , Imageamento Tridimensional/métodos , Cifose/diagnóstico por imagem , Cifose/fisiopatologia , Masculino , Postura/fisiologia , Estudos Prospectivos , Radiografia , Escoliose/fisiopatologia , Postura Sentada , Coluna Vertebral/diagnóstico por imagem , Posição Ortostática , Ultrassonografia/métodos
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