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1.
J Neuroeng Rehabil ; 20(1): 32, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932449

RESUMO

BACKGROUND: Coordinated control between the bilateral ankle joints plays an important role in performing daily life functions, such as walking and running. However, few studies have explored the impact of stroke on movement disorders that decrease the coordination control of the bilateral extremities and may decrease daily activities that require coordination control of the bilateral ankles. This study aimed to investigate the coordination control of the bilateral ankles using a novel bilateral ankle measurement system and evaluate the relationship of bilateral movement coordination control deficits with motor and functional performances of the lower extremities in patients with stroke. METHODS: Twenty-one healthy adults (36.5 ± 13.2 y/o) and 19 patients with chronic stroke (58.7 ± 10.5 y/o) were enrolled. A novel measurement device with embedded rotary potentiometers was used to evaluate bilateral ankle coordination control. Participants were asked to move their dominant (non-paretic) foot from dorsiflexion to plantarflexion position and non-dominant (paretic) foot from dorsiflexion to plantarflexion position (condition 1) simultaneously, and vice versa (condition 2). Alternating time and angle for coordination control with movements of both ankles were calculated for each condition. Motor and functional performance measurements of the lower extremities included the lower-extremity portion of the Fugl-Meyer assessment (FMA-LE), Berg Balance Test (BBS), Timed Up and Go Test (TUG), and Barthel Index (BI). RESULTS: Compared with the healthy group, alternating time was shorter in the stroke group by 8.3% (p = 0.015), and the alternating angles of conditions 1 and 2 were significantly higher than those of the healthy group by 1.4° (p = 0.001) and 2.5° (p = 0.013), respectively. The alternating angle in condition 2 showed moderate correlations with TUG (r = 0.512; p = 0.025), 10-m walk (r = 0.747; p < 0.001), gait speed (r = - 0.497 to - 0.491; p < 0.05), length (r = - 0.518 to - 0.551; p < 0.05), and BI (r = - 0.457; p = 0.049). CONCLUSION: Stroke decreases alternating time, increases alternating angle, and shows bilateral ankle coordination control deficits temporally and spatially. A higher alternating angle is moderately to highly associated with motor function and lower limb function in patients with stroke.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Humanos , Tornozelo , Articulação do Tornozelo , Equilíbrio Postural , Estudos de Tempo e Movimento , Extremidade Inferior , Acidente Vascular Cerebral/complicações , Caminhada
2.
Curr Opin Microbiol ; 71: 102232, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36368294

RESUMO

Type-3 secretion system injectisomes are multiprotein complexes that translocate bacterial effector proteins from the cytoplasm of gram-negative bacteria directly into the cytosol of eukaryotic host cells. These systems are present in more than 30 bacterial species, including numerous human, animal, and plant pathogens. We review recent discoveries of structural and molecular mechanisms of effector protein translocation through the injectisomes and recent advances in the understanding of mechanisms of activation of effector protein secretion.


Assuntos
Proteínas de Bactérias , Sistemas de Secreção Tipo III , Animais , Humanos , Sistemas de Secreção Tipo III/metabolismo , Transporte Proteico , Proteínas de Bactérias/metabolismo , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/metabolismo , Células Eucarióticas
3.
Front Med (Lausanne) ; 9: 1008950, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275805

RESUMO

Purpose: Diabetic macular edema (DME) is one of the leading causes of visual impairment in diabetic retinopathy (DR). Physicians rely on optical coherence tomography (OCT) and baseline visual acuity (VA) to tailor therapeutic regimen. However, best-corrected visual acuity (BCVA) from chart-based examinations may not wholly reflect DME status. Chart-based examinations are subjected findings dependent on the patient's recognition functions and are often confounded by concurrent corneal, lens, retinal, optic nerve, or extraocular disorders. The ability to infer VA from objective optical coherence tomography (OCT) images provides the predicted VA from objective macular structures directly and a better understanding of diabetic macular health. Deviations from chart-based and artificial intelligence (AI) image-based VA will prompt physicians to assess other ocular abnormalities affecting the patients VA and whether pursuing anti-VEGF treatment will likely yield increment in VA. Materials and methods: We enrolled a retrospective cohort of 251 DME patients from Big Data Center (BDC) of Taipei Veteran General Hospital (TVGH) from February 2011 and August 2019. A total of 3,920 OCT images, labeled as "visually impaired" or "adequate" according to baseline VA, were grouped into training (2,826), validation (779), and testing cohort (315). We applied confusion matrix and receiver operating characteristic (ROC) curve to evaluate the performance. Results: We developed an OCT-based convolutional neuronal network (CNN) model that could classify two VA classes by the threshold of 0.50 (decimal notation) with an accuracy of 75.9%, a sensitivity of 78.9%, and an area under the ROC curve of 80.1% on the testing cohort. Conclusion: This study demonstrated the feasibility of inferring VA from routine objective retinal images. Translational relevance: Serves as a pilot study to encourage further use of deep learning in deriving functional outcomes and secondary surrogate endpoints for retinal diseases.

4.
J Chin Med Assoc ; 85(1): 24-29, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34643619

RESUMO

Electrotherapy or electrical stimulation (ES) is a part of clinical intervention in the rehabilitation field. With rehabilitation intervention, electrotherapy may be provided as a treatment for pain relief, strengthening, muscle education, wound recovery, or functional training. Although these interventions may not be considered as the primary therapy for patients, the advantages of the ease of operation, lower costs, and lower risks render ES to be applied frequently in clinics. There have also been emerging ES tools for brain modulation in the past decade. ES interventions are not only considered analgesics but also as an important assistive therapy for motor improvement in orthopedic and neurological rehabilitation. In addition, during the coronavirus disease pandemic, lockdowns and self-quarantine policies have led to the discontinuation of orthopedic and neurological rehabilitation interventions. Therefore, the feasibility and effectiveness of home-based electrotherapy may provide opportunities for the prevention of deterioration or extension of the original therapy. The most common at-home applications in previous studies showed positive effects on pain relief, functional ES, muscle establishment, and motor training. Currently, there is a lack of certain products for at-home brain modulation; however, transcranial direct current stimulation has shown the potential of future home-based rehabilitation due to its relatively small and simple design. We have organized the features and applications of ES tools and expect the future potential of remote therapy during the viral pandemic.


Assuntos
COVID-19/epidemiologia , Terapia por Estimulação Elétrica/métodos , Reabilitação Neurológica , Procedimentos Ortopédicos , SARS-CoV-2 , Terapia por Estimulação Elétrica/efeitos adversos , Humanos , Estimulação Transcraniana por Corrente Contínua , Estimulação Elétrica Nervosa Transcutânea
5.
BMC Geriatr ; 21(1): 703, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911487

RESUMO

BACKGROUND: Operating an object by generating stable hand-grip force during static or dynamic posture control of the upper extremities simultaneously is an important daily activity. Older adults require different attentional resources during grip strength control and arm movements. However, the impact of aging and reaching movements on precise grip strength and stability control among older adults is not well understood. This study investigated the impact of aging and reaching movements on grip strength and stability control in both hands of the upper extremities. METHODS: Fifty healthy young adults (age: 28.8 ± 14.0 years) and 54 healthy older adults (73.6 ± 6.3 years) were recruited to perform isometric grip strength test at 20% maximal voluntary contraction as the target force during three manual precision tasks simultaneously: stationary task (without arm movements), forward-reach task, and backward-reach task. The average grip force (in kg) and coefficient of variation values (expressed as a percentage) during manual precision tasks were calculated to determine the quality of participants' grip strength. The deviation error, absolute error, and force-stability index values were calculated to determine the strength control relative to the target force. RESULTS: For both the young and older groups, the force-stability index values in both hands were significantly higher during forward- and backward-reaching movements than in the stationary condition (p < 0.05). The older group exhibited a significantly lower hand-grip strength and stability of strength control in both hands than the young group (p < 0.05). CONCLUSIONS: Aging and reaching task performance reduced the grip strength of participants and increased the variations in strength control of both hands relative to the target force, indicating that older adults exhibit poor grip strength and stability control when performing arm-reaching movements. These findings may help clinical therapists in establishing objective indexes for poor grip-stability control screening and developing appropriate rehabilitation programs or health-promotion exercises that can improve grip strength and stability control in older people.


Assuntos
Força da Mão , Mãos , Atividades Cotidianas , Idoso , Envelhecimento , Humanos , Movimento
6.
mBio ; 12(6): e0302121, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34809452

RESUMO

Shigella spp. are human bacterial pathogens that cause bacillary dysentery. Virulence depends on a type 3 secretion system (T3SS), a highly conserved structure present in multiple important human and plant pathogens. Upon host cell contact, the T3SS translocon is delivered to the host membrane, facilitates bacterial docking to the membrane, and enables delivery of effector proteins into the host cytosol. The Shigella translocon is composed of two proteins, IpaB and IpaC, which together form this multimeric structure within host plasma membranes. Upon interaction of IpaC with host intermediate filaments, the translocon undergoes a conformational change that allows for bacterial docking onto the translocon and, together with host actin polymerization, enables subsequent effector translocation through the translocon pore. To generate additional insights into the translocon, we mapped the topology of IpaB in plasma membrane-embedded pores using cysteine substitution mutagenesis coupled with site-directed labeling and proximity-enabled cross-linking by membrane-permeant sulfhydryl reactants. We demonstrate that IpaB function is dependent on posttranslational modification by a plasmid-encoded acyl carrier protein. We show that the first transmembrane domain of IpaB lines the interior of the translocon pore channel such that the IpaB portion of the channel forms a funnel-like shape leading into the host cytosol. In addition, we identify regions of IpaB within its cytosolic domain that protrude into and are closely associated with the pore channel. Taken together, these results provide a framework for how IpaB is arranged within translocons natively delivered by Shigella during infection. IMPORTANCE Type 3 secretion systems are nanomachines employed by many bacteria, including Shigella, which deliver into human cells bacterial virulence proteins that alter cellular function in ways that promote infection. Delivery of Shigella virulence proteins occurs through a pore formed in human cell membranes by the IpaB and IpaC proteins. Here, we define how IpaB contributes to the formation of pores natively delivered into human cell membranes by Shigella flexneri. We show that a specific domain of IpaB (transmembrane domain 1) lines much of the pore channel and that portions of IpaB that lie in the inside of the human cell loop back into and/or are closely associated with the pore channel. These findings provide new insights into the organization and function of the pore in serving as the conduit for delivery of virulence proteins into human cells during Shigella infection.


Assuntos
Proteínas de Bactérias/metabolismo , Membrana Celular/microbiologia , Disenteria Bacilar/microbiologia , Shigella flexneri/metabolismo , Transferases/metabolismo , Sistemas de Secreção Tipo III/química , Sistemas de Secreção Tipo III/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Membrana Celular/química , Humanos , Domínios Proteicos , Shigella flexneri/química , Shigella flexneri/genética , Transferases/genética , Sistemas de Secreção Tipo III/genética
7.
PLoS Pathog ; 17(9): e1009932, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34499700

RESUMO

Many bacterial pathogens require a type 3 secretion system (T3SS) to establish a niche. Host contact activates bacterial T3SS assembly of a translocon pore in the host plasma membrane. Following pore formation, the T3SS docks onto the translocon pore. Docking establishes a continuous passage that enables the translocation of virulence proteins, effectors, into the host cytosol. Here we investigate the contribution of actin polymerization to T3SS-mediated translocation. Using the T3SS model organism Shigella flexneri, we show that actin polymerization is required for assembling the translocon pore in an open conformation, thereby enabling effector translocation. Opening of the pore channel is associated with a conformational change to the pore, which is dependent upon actin polymerization and a coiled-coil domain in the pore protein IpaC. Analysis of an IpaC mutant that is defective in ruffle formation shows that actin polymerization-dependent pore opening is distinct from the previously described actin polymerization-dependent ruffles that are required for bacterial internalization. Moreover, actin polymerization is not required for other pore functions, including docking or pore protein insertion into the plasma membrane. Thus, activation of the T3SS is a multilayered process in which host signals are sensed by the translocon pore leading to the activation of effector translocation.


Assuntos
Actinas/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Shigella flexneri/patogenicidade , Sistemas de Secreção Tipo III/metabolismo , Virulência/fisiologia , Disenteria Bacilar/metabolismo , Células HeLa , Humanos , Polimerização , Shigella flexneri/metabolismo
8.
BMC Geriatr ; 21(1): 449, 2021 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-34332537

RESUMO

BACKGROUND: Degenerative osteoarthritis (OA) often leads to pain and stiffness of the affected joints, which may affect the physical performance and decrease the quality of life of people with degenerative knee OA. Compared to traditional exercise, tai chi is a safe exercise with slow movements which can facilitate physical functioning and psychological well being, and might be suitable for improving the physical activities of older adults with knee OA. Therefore, this study investigated the impacts of tai chi exercise on the functional fitness of community-dwelling older adults with degenerative knee OA. METHODS: Sixty-eight community-dwelling older adults with knee OA were recruited from the local community to participate in this randomized controlled clinical trial. All subjects were randomly assigned to either an TCE group that practiced tai chi exercise (TCE) (n = 36) or a control group (CON) (n = 32) that received regular health education programs twice per week for 12 weeks. Outcome measurements were determined using functional fitness tests before and after the intervention, including a 30-s chair stand (number of repeats), 30-s arm-curl (number of repeats), 2-min step (number of steps), chair sit-and-reach (reaching distance, cm), back-scratch flexibility (distance between hands, cm), single-leg stand (time, s), functional reach (reaching distance, cm), 8-foot up-and-go (time, s), and 10-m walk tests (time, s). Pre-post comparisons of functional fitness were analyzed using the ANCOVA test with SPSS software version 18.0. RESULTS: Results revealed that participants' functional fitness in the TCE group had significantly higher adjusted mean post-tests scores than that in the CON group after the intervention, including the 8-foot up-and-go (s) (mean difference [MD]=-2.92 [-3.93, -1.91], p = 2.39*10- 7), 30-s arm curl (MD = 4.75 (2.76, 6.73), p = 1.11*10- 5), 2-min step (MD = 36.94 [23.53, 50.36], p = 7.08*10- 7), 30-s chair stand (MD = 4.66 [2.97, 6.36], p = 6.96*10- 7), functional-reach (MD = 5.86 [3.52, 8.20], p = 4.72*10- 6), single-leg stand with eyes closed (MD = 3.44 [1.92, 4.97], p = 2.74*10- 5), chair sit-and-reach (MD = 3.93 [1.72, 6.15], p = 0.001), and single-leg stand with eyes opened (MD = 17.07 [6.29, 27.85], p = 0.002), with large effect sizes (η²=0.14 ~ 0.34). CONCLUSIONS: Community-dwelling older adults with knee OA in the TCE group had better functional fitness performances after the 12-week tai chi intervention than those receiving only health education.


Assuntos
Osteoartrite do Joelho , Tai Chi Chuan , Idoso , Exercício Físico , Humanos , Vida Independente , Osteoartrite do Joelho/terapia , Aptidão Física , Qualidade de Vida
9.
Sensors (Basel) ; 21(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199926

RESUMO

Considering the trend of aging societies, accompanying technology can help frail, elderly individuals participate in daily activities. The ideal accompanying robot should accompany the user in a proper position according to the activity scenarios and context; the prerequisite is that the accompanying robot should quickly move to a designated position and closely maintain it regardless of the direction in which the user moves. This paper proposes a user local coordinate-based strategy to satisfy this need. As a proof of concept, a novel "string-pot" approach was utilized to measure the position difference between the robot and the target. We implemented the control strategy and assessed its performance in our gait lab. The results showed that the robot can follow the user in the designated position while the user performs forward, backward, and lateral movements, turning, and walking along a curve.


Assuntos
Robótica , Idoso , Idoso Fragilizado , Marcha , Humanos , Movimento , Caminhada
10.
J Chin Med Assoc ; 84(8): 754-756, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34145198

RESUMO

Osteoarthritis (OA) is a common degenerative disease; however, its exact pathophysiology and early diagnosis are still a challenge. Growing attention to the exosomes may inspire innovations that would make the current management of OA more effective. The exosomes in synovial fluid are relatively stable, and they can be easily isolated by the relatively noninvasive procedure of liquid biopsy to provide diagnostic and monitoring value. Some miRNAs (miR-504, miR-146a, miR-26a, miR-200c, and miR-210) have been known to be secreted in exosomes of OA patients. On the other hand, intraarticular injection of platelet-rich plasma (PRP) is becoming a popular therapy for OA patients. PRP is also a source of exosomes and their numerous contents. It is evident from the literature that PRP-derived exosomes can induce chondrogenic gene expression in OA chondrocytes. Here, we review the latest findings on the roles of exosomes in OA with the emphasis on PRP-derived exosomes and their potential applications for treating OA.


Assuntos
Exossomos/metabolismo , Osteoartrite/fisiopatologia , Biomarcadores , Feminino , Humanos , Biópsia Líquida , Masculino , Líquido Sinovial
11.
Comp Med ; 71(2): 166-176, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33536115

RESUMO

The use of percutaneous cranial implants in rhesus macaques (Macaca mulatta) has long been a valuable tool for neuroscience research. However, when treating and assessing these animals, veterinarians are required to make assumptions about diagnostic results due to a lack of research into how these implants affect physiology. Microbial cultures of cranial implant sites show an abundance of colonizing bacteria, but whether these microbes affect animal health and wellbeing is poorly understood. In addition, microbial antibiotic resistance can present significant health concerns for both the animals and the researchers. To help elucidate the relationship between percutaneous cranial implants and blood parameters, complete blood cell counts and serum chemistry results were assessed on 57 nonhuman primates at our institution from September 2001 to March 2017. Generalized estimating equations were used to compare the results before and after an animal's first implant surgery. This modelling showed that cranial implants were a significant predictor of alterations in the number of neutrophils, lymphocytes, and red blood cells, and in the concentration of hemoglobin, alkaline phosphatase, creatinine, calcium, phos- phorus, total protein, albumin, and globulin. Anaerobic and aerobic bacterial cultures were performed to identify bacteria associated with cranial implants. Staphylococcus spp., Streptococcus spp., and Corynebacterium spp. comprised the majority of the aerobic bacterial isolates, while Fusobacterium spp., Peptostreptococcus spp. and Bacterioides fragilis comprised the majority of anaerobic bacterial isolates. Using a Pearson r correlation for statistical analysis, we assessed whether any of these bacterial isolates developed antibiotic resistances over time. Cefazolin, the most frequently used antibiotic in monkeys in this study, was the only antimicrobial out of 41 agents tested to which bacteria developed resistance over time. These results indicate that percutaneous implants are associated with a generalized inflammatory state, multiple bacterial species are present at the implant site, and these bacteria may contribute to the inflammatory response.


Assuntos
Hematologia , Próteses e Implantes , Animais , Macaca mulatta , Staphylococcus , Streptococcus
12.
Sci Rep ; 11(1): 4229, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608568

RESUMO

A single-blind study to investigate the effects of noisy galvanic vestibular stimulation (nGVS) in straight walking and 2 Hz head yaw walking for healthy and bilateral vestibular hypofunction (BVH) participants in light and dark conditions. The optimal stimulation intensity for each participant was determined by calculating standing stability on a force plate while randomly applying six graded nGVS intensities (0-1000 µA). The chest-pelvic (C/P) ratio and lateral deviation of the center of mass (COM) were measured by motion capture during straight and 2 Hz head yaw walking in light and dark conditions. Participants were blinded to nGVS served randomly and imperceivably. Ten BVH patients and 16 healthy participants completed all trials. In the light condition, the COM lateral deviation significantly decreased only in straight walking (p = 0.037) with nGVS for the BVH. In the dark condition, both healthy (p = 0.026) and BVH (p = 0.017) exhibited decreased lateral deviation during nGVS. The C/P ratio decreased significantly in BVH for 2 Hz head yaw walking with nGVS (p = 0.005) in light conditions. This study demonstrated that nGVS effectively reduced walking deviations, especially in visual deprived condition for the BVH. Applying nGVS with different head rotation frequencies and light exposure levels may accelerate the rehabilitation process for patients with BVH.Clinical Trial Registration This clinical trial was prospectively registered at www.clinicaltrials.gov with the Unique identifier: NCT03554941. Date of registration: (13/06/2018).


Assuntos
Estimulação Elétrica , Ruído , Equilíbrio Postural , Privação Sensorial , Vestíbulo do Labirinto/fisiopatologia , Visão Ocular , Adulto , Idoso , Feminino , Marcha , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Desempenho Psicomotor , Caminhada
13.
J Vestib Res ; 31(1): 23-32, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33325420

RESUMO

BACKGROUND: Embedded within most rapid head rotations are gaze shifts, which is an initial eye rotation to a target of interest, followed by a head rotation towards the same target. Gaze shifts are used to acquire an image that initially is outside of the participant's current field of vision. Currently, there are no tools available that evaluate the functional relevance of a gaze shift. OBJECTIVE: The purpose of our study was to measure dynamic visual acuity (DVA) while performing a gaze shift. METHODS: Seventy-one healthy participants (42.79±16.89 years) and 34 participants with unilateral vestibular hypofunction (UVH) (54.59±20.14 years) were tested while wearing an inertial measurement unit (IMU) sensor on the head and walking on a treadmill surrounded by three monitors. We measured visual acuity during three subcomponent tests: standing (static visual acuity), while performing an active head rotation gaze shift, and an active head rotation gaze shift while walking (gsDVAw). RESULTS: While doing gsDVAw, patients with Left UVH (n = 21) had scores worse (p = 0.023) for leftward (0.0446±0.0943 LogMAR) head rotation compared with the healthy controls (-0.0075±0.0410 LogMAR). Similarly, patients with right UVH (N = 13) had worse (p = 0.025) gsDVAw for rightward head motion (0.0307±0.0481 LogMAR) compared with healthy controls (-0.0047±0.0433 LogMAR). As a whole, gsDVAw scores were worse in UVH compared to the healthy controls when we included the ipsilesional head rotation on both sides gsDVAw (0.0061±0.0421 LogMAR healthy vs. 0.03926±0.0822 LogMAR UVH, p = 0.003). Controlling for age had no effect, the gsDVAw scores of the patients were always worse (p < 0.01). CONCLUSION: The gaze shift DVA test can distinguish gaze stability in patients with UVH from healthy controls. This test may be a useful measure of compensation for patients undergoing various therapies for their vestibular hypofunction.


Assuntos
Movimentos da Cabeça , Doenças Vestibulares , Humanos , Reflexo Vestíbulo-Ocular , Doenças Vestibulares/diagnóstico , Testes Visuais , Acuidade Visual , Caminhada
14.
Brain Sci ; 10(10)2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33076417

RESUMO

Patients with bilateral vestibular hypofunction (BVH) often suffer from imbalance, gait problems, and oscillopsia. Noisy galvanic vestibular stimulation (GVS), a technique that non-invasively stimulates the vestibular afferents, has been shown to enhance postural and walking stability. However, no study has investigated how it affects stability and neural activities while standing and walking with a 2 Hz head yaw turning. Herein, we investigated this issue by comparing differences in neural activities during standing and walking with a 2 Hz head turning, before and after noisy GVS. We applied zero-mean gaussian white noise signal stimulations in the mastoid processes of 10 healthy individuals and seven patients with BVH, and simultaneously recorded electroencephalography (EEG) signals with 32 channels. We analyzed the root mean square (RMS) of the center of pressure (COP) sway during 30 s of standing, utilizing AMTI force plates (Advanced Mechanical Technology Inc., Watertown, MA, USA). Head rotation quality when walking with a 2 Hz head yaw, with and without GVS, was analyzed using a VICON system (Vicon Motion Systems Ltd., Oxford, UK) to evaluate GVS effects on static and dynamic postural control. The RMS of COP sway was significantly reduced during GVS while standing, for both patients and healthy subjects. During walking, 2 Hz head yaw movements was significantly improved by noisy GVS in both groups. Accordingly, the EEG power of theta, alpha, beta, and gamma bands significantly increased in the left parietal lobe after noisy GVS during walking and standing in both groups. GVS post-stimulation effect changed EEG activities in the left and right precentral gyrus, and the right parietal lobe. After stimulation, EEG activity changes were greater in healthy subjects than in patients. Our findings reveal noisy GVS as a non-invasive therapeutic alternative to improve postural stability in patients with BVH. This novel approach provides insight to clinicians and researchers on brain activities during noisy GVS in standing and walking conditions in both healthy and BVH patients.

15.
J Chin Med Assoc ; 83(11): 1039-1047, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32773591

RESUMO

BACKGROUND: Frailty syndrome in older population generates formidable social cost. The early detection of "prefrail" stage is essential so that interventions could be performed to prevent deterioration. The purpose of this study was to organize appropriate physical performance tests into a computerized early frailty screening platform, called frailty assessment tools (FAT) system, to detect individuals who are in the prefrail stage. METHODS: Four switches, one distance meter, and one power measure were adopted to build the FAT system that could perform six physical performance tests including single leg standing (SLS), repeated chair rise, timed up and go, self-selected walking speed, functional reach, and grip power. Participants over 65 years old were recruited and classified into three groups according to Fried criteria. The differences in variables between prefrail and robust groups were compared by the χ test, independent samples t test, and Mann-Whitney U test, for nominal variables, normal, and non-normal distributive continuous variables, respectively. The statistically significant level was set at 0.05 (α = 0.05). RESULTS: Only SLS did not reach significance to distinguish prefrail from robust. Among 35 participants (73.23 ± 5.70 years old), the FAT score predicted that 90.73 ± 19.95% of pre-frail subjects and 15.01 ± 25.25% of robust subjects were in the prefrail stage. CONCLUSION: The FAT system, which provides results immediately, is an advantageous alternative to traditional manual measurements. The use of the FAT score for predicting the prefrail stage will help to provide early intervention to prevent individuals from progressing into frailty. The FAT system provides a more convenient and comprehensive frailty screening. Using this computerized automatic screening platform, it may be possible to expand the scope of frailty prevention.


Assuntos
Fragilidade/diagnóstico , Smartphone , Idoso , Idoso de 80 Anos ou mais , Feminino , Avaliação Geriátrica , Humanos , Masculino
16.
J Chin Med Assoc ; 83(10): 898-899, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32520771

RESUMO

Artificial intelligence (AI) has been widely applied in the medical field and achieved enormous milestones in helping specialists to make diagnosis and remedy decisions, particularly in the field of eye diseases and ophthalmic screening. With the development of AI-based systems, the enormous hardware and software resources are required for optimal performance. In reality, there are many places on the planet where such resources are highly limited. Hence, the smartphone-based AI systems can be used to provide a remote control route to quickly screen eye diseases such as diabetic-related retinopathy or diabetic macular edema. However, the performance of such mobile-based AI systems is still uncharted territory. In this article, we discuss the issues of computing resource consumption and performance of the mobile device-based AI systems and highlight recent research on the feasibility and future potential of application of the mobile device-based AI systems in telemedicine.


Assuntos
Inteligência Artificial , Oftalmopatias/diagnóstico , Smartphone , Telemedicina , Humanos
17.
Front Neurol ; 11: 485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32595589

RESUMO

To evaluate vestibular function in the clinic, current assessments are applied under static conditions, such as with the subject in a sitting or supine position. Considering the complexities of daily activities, the combination of dynamic activities, dynamic visual acuity (DVA) and postural control could produce an evaluation that better reflects vestibular function in daily activities. Objective: To develop a novel sensor-based system to investigate DVA, walking trajectory, head and trunk movements and the chest-pelvis rotation ratio during forward and backward overground walking in both healthy individuals and patients with vestibular hypofunction. Methods: Fifteen healthy subjects and 7 patients with bilateral vestibular hypofunction (BVH) were recruited for this study. Inertial measurement units were placed on each subject's head and torso. Each subject walked forward and backward for 5 m twice with 2 Hz head yaw. Our experiment comprised 2 stages. In stage 1, we measured forward (FW), backward (BW), and medial-lateral (MLW) walking trajectories; head and trunk movements; and the chest-pelvis rotation ratio. In stage 2, we measured standing and locomotion DVA (loDVA). Using Mann-Whitney U-test, we compared the abovementioned parameters between the 2 groups. Results: Patients exhibited an in-phase chest/pelvis reciprocal rotation ratio only in FW. The walking trajectory deviation, calculated by normalizing the summation of medial-lateral swaying with 1/2 body height (%), was significantly larger (FW mean ± standard deviation: 20.4 ± 7.1% (median (M)/interquartile range (IQR): 19.3/14.4-25.2)in healthy vs. 43.9 ± 27. 3% (M/IQR: 36.9/21.3-56.9) in patients, p = 0.020)/(BW mean ± standard deviation: 19.2 ± 11.5% (M/IQR: 13.6/10.4-25.3) in healthy vs. 29.3 ± 6.4% (M/IQR: 27.7/26.5-34.4) in patients, p = 0.026), and the walking DVA was also significantly higher (LogMAR score in the patient group [FW LogMAR: rightDVA: mean ± standard deviation:0.127 ± 0.081 (M/IQR: 0.127/0.036-0.159) in healthy vs. 0.243 ± 0.101 (M/IQR: 0.247/0.143-0.337) in patients (p = 0.013) and leftDVA: 0.136 ± 0.096 (M/IQR: 0.127/0.036-0.176) in healthy vs. 0.258 ± 0.092 (M/IQR: 0.247/0.176-0.301) in patients (p = 0.016); BW LogMAR: rightDVA: mean ± standard deviation: 0.162 ± 0.097 (M/IQR: 0.159/0.097-0.273) in healthy vs. 0.281 ± 0.130 (M/IQR: 0.273/0.176-0.418) in patients(p = 0.047) and leftDVA: 0.156 ± 0.101 (M/IQR: 0.159/0.097-0.198) in healthy vs. 0.298 ± 0.153 (M/IQR: 0.2730/0.159-0.484) in patients (p = 0.038)]. Conclusions: Our sensor-based vestibular evaluation system provided a more functionally relevant assessment for the identification of BVH patients.

18.
J Chin Med Assoc ; 83(11): 981-983, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32568967

RESUMO

Artificial intelligence (AI), Internet of Things (IoT), and telemedicine are deeply involved in our daily life and have also been extensively applied in the medical field, especially in ophthalmology. Clinical ophthalmologists are required to perform a vast array of image exams and analyze images containing complicated information, which allows them to diagnose the disease type and grade, make a decision on remedy, and predict treatment outcomes. AI has a great potential to assist ophthalmologists in their daily routine of image analysis and relieve their work burden. However, in spite of these prospects, the application of AI may also be controversial and associated with several legal, ethical, and sociological concerns. In spite of these issues, AI has indeed become an irresistible trend and is widely used by medical specialists in their daily routines in what we can call now, the era of AI. This review will encompass those issues and focus on recent research on the AI application in ophthalmology and telemedicine.


Assuntos
Inteligência Artificial , Oftalmologia , Telemedicina , Retinopatia Diabética/diagnóstico , Glaucoma/diagnóstico , Humanos , Degeneração Macular/diagnóstico , Redes Neurais de Computação
19.
Sensors (Basel) ; 20(12)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549401

RESUMO

This paper demonstrates the development of an automatic mobile trainer employing inertial movement units (IMUs). The device is inspired by Neuro-Developmental Treatment (NDT), which is an effective rehabilitation method for stroke patients that promotes the relearning of motor skills by repeated training. However, traditional NDT training is very labor intensive and time consuming for therapists, thus, stroke patients usually cannot receive sufficient rehabilitation training. Therefore, we developed a mobile assisted device that can automatically repeat the therapists' intervention and help increase patient training time. The proposed mobile trainer, which allows the users to move at their preferred speeds, consists of three systems: the gait detection system, the motor control system, and the movable mechanism. The gait detection system applies IMUs to detect the user's gait events and triggers the motor control system accordingly. The motor control system receives the triggering signals and imitates the therapist's intervention patterns by robust control. The movable mechanism integrates these first two systems to form a mobile gait-training device. Finally, we conducted preliminary tests and defined two performance indexes to evaluate the effectiveness of the proposed trainer. Based on the results, the mobile trainer is deemed successful at improving the testing subjects' walking ability.


Assuntos
Análise da Marcha/instrumentação , Transtornos Neurológicos da Marcha/diagnóstico , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Caminhada
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