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1.
J Immunother Cancer ; 7(1): 268, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31639056

RESUMO

BACKGROUND: The aim of this study is to profile the cytokines and immune cells of body fluid from metastatic gastric cancer (mGC), and evaluate the potential role as a prognostic factor and the feasibility as a predictive biomarker or monitoring source for immune checkpoint inhibitor. METHODS: Body fluid including ascites and pleural fluid were obtained from 55 mGC patients and 24 matched blood. VEGF-A, IL-10, and TGF-ß1 were measured and immune cells were profiled by fluorescence assisted cell sorting (FACS). RESULTS: VEGF-A and IL-10 were significantly higher in body fluid than in plasma of mGC. Proportion of T lymphocytes with CD69 or PD-1, memory T cell marked with CD45RO, and number of Foxp3+ T regulatory cells (Tregs) were significantly higher in body fluid than those in blood of mGC. Proportion of CD8 T lymphocyte with memory marker (CD45RO) and activation marker (HLA-DR), CD3 T lymphocyte with PD-1, and number of FoxP3+ Tregs were identified as independent prognostic factors. When patients were classified by molecular subgroups of primary tumor, VEGF-A was significantly higher in genomically stable (GS)-like group than that in chromosomal instability (CIN)-like group while PD-L1 positive tumor cells (%) showed opposite results. Monitoring immune dynamics using body fluid was also feasible. Early activated T cell marked with CD25 was significantly increased in chemotherapy treated group. CONCLUSIONS: By analyzing cytokines and proportion of immune cells in body fluid, prognosis of patients with mGC can be predicted. Immune monitoring using body fluid may provide more effective treatment for patients with mGC.

2.
Front Neurorobot ; 13: 72, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551747

RESUMO

Motor disabilities limiting the mobility of limbs affect the quality of lives of people with neural injuries. Among various types of motor disabilities, abnormal intermuscular coordination is commonly observed from people with severe impairment. The concept of muscle synergy, defined as characteristic muscle co-activation patterns activated to produce complex motor behavior, has been applied to assess the alteration in intermuscular coordination in pathological populations. This study presents the development of a robotic system named KAIST upper limb synergy investigation system (KULSIS), for accurate measurement of intermuscular synergies while providing the convenient experimental setup. It provides full force/moment measurements for isometric force generation tasks at various upper limb postures and reaching tasks in a three-dimensional workspace. It is composed of: a three-degree-of-freedom gimbaled handle to adjust the orientation of the handle to accommodate potential hand-wrist deformity, a linear actuator that moves the handle for reaching tasks; a five-degree-of-freedom mechanism for positioning and adjusting the orientation of the linear actuator. The design was evaluated in terms of the workspace of the handle, mechanical stiffness and force/moment measurement accuracy. The position/force measurement is synchronized with electromyographic measurements. Muscle synergy patterns, activated during four isokinetic reaching motions, were also assessed as preliminary data using KULSIS from ten healthy subjects.

3.
IEEE Trans Neural Syst Rehabil Eng ; 27(10): 2107-2117, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31484125

RESUMO

Cable-driven devices for hands allow compact and lightweight design that could provide various functional movements. However, for many patients post-stroke, cable-driven devices produce nonphysiologic movements, such as metacarpophalangeal joint hyperextension, due to their abnormal passive joint impedance. In this study, we developed a novel bio-inspired device mimicking the anatomy of the extensor mechanism of the human finger, which can be tuned for individuals to provide 'subject-specific' assistance to achieve physiological movement patterns. We first evaluated the proposed design via mathematical modeling and computer simulation. Its performance was then tested experimentally with twenty-four subjects, including six healthy and eighteen chronic stroke survivors. We determined the loading condition of the device from the experimental identification of passive joint impedance of each subject before device use. Our results showed that the proposed design could achieve improved spatiotemporal coordination of finger movements compared to conventional cable-driven design by providing 'subject-specific' assistance based on identified passive stiffness values of each subject. We also identified a significant (negative) correlation between the metacarpophalangeal joint stiffness and the intrinsic exotendon loading level across subjects. The proposed system can restore normal movement patterns for patients with different types of impairments, which were previously found important in improving rehabilitative outcomes.

4.
IEEE Int Conf Rehabil Robot ; 2019: 583-586, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31374693

RESUMO

This paper analyses the time-window size required to achieve the highest accuracy of the convolutional neural network (CNN) in classifying periodic upper limb rehabilitation. To classify real-time motions by using CNN-based human activity recognition (HAR), data must be segmented using a time window. In particular, for the repetitive rehabilitation tasks, the relationship between the period of the repetitive tasks and optimal size of the time window must be analyzed. In this study, we constructed a data-collection system composed of a smartwatch and smartphone. Five upper limb rehabilitation motions were measured for various periods to classify the rehabilitation motions for a particular time-window size. 5-fold cross-validation technique was used to compare the performance. The results showed that the size of the time-window that maximizes the performance of CNN-based HAR is affected by the size and period of the sample used.


Assuntos
Terapia por Exercício/instrumentação , Movimento , Processamento de Sinais Assistido por Computador , Dispositivos Eletrônicos Vestíveis , Adulto , Humanos , Masculino
5.
J Orthop Res ; 37(11): 2437-2444, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31286563

RESUMO

The relationship between arthritis or repetitive stress injuries (RSIs) in thumbs and rapidly increasing hours of smartphone usage is not fully elucidated. We evaluated axial joint reaction forces (AJRFs) and thumb torques in 19 healthy subjects performing typical smartphone tasks, which included tapping, tap game, and swiping. We measured force and torque when a subject tapped or swiped the panel of the smartphone and analyzed the motions of each joint using surface markers and motion capture systems. We calculated AJRFs and torques on each thumb joint using inverse dynamics. The results were then compared with representative activities such as computer keyboard typing and handwriting. The mean AJRFs/torques at the thumb carpometacarpal joint (CMCJ) while tapping the smartphone and tap gaming were 12.5 N/95.5 N mm and 21.1 N/187.21 N mm, respectively. AJRFs and torques were significantly higher during tap gaming activities than during simple tapping subtasks (p = 0.003 and p < 0.001, respectively). Compared with those during computer keyboard typing, the mean AJRFs and torques at the CMCJ during smartphone tapping was 3 (p = 0.075) and 1.4 times (p = 0.680) larger, respectively. Considering the rapidly increasing dependency on smartphones in our daily lives, long-term exposure of the thumb to repetitive AJRFs and torques may lead to an acceleration of arthritis or aggravation of RSIs in thumbs. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2437-2444, 2019.


Assuntos
Transtornos Traumáticos Cumulativos/etiologia , Articulação da Mão/fisiologia , Smartphone , Polegar/fisiologia , Atividades Cotidianas , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Torque , Adulto Jovem
6.
J Neural Eng ; 16(6): 066013, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31344687

RESUMO

OBJECTIVE: The development of non-invasive, quickly reversible techniques for controlling undesired muscle force production (e.g. spasticity) could expand rehabilitation approaches in those with pathology by increasing the type and intensity of exercises that can be performed. High-frequency alternating current (HFAC) has been previously established as a viable method for blocking neural conduction in peripheral nerves. However, clinical application of HFAC for nerve conduction block is limited due to the invasiveness of surgical procedures and the painful onset response. This study aimed to examine the use of transcutaneous HFAC (tHFAC) at various stimulation frequencies to address these shortfalls. APPROACH: Ten individuals participated in the study. Surface electrodes were utilized to apply tHFAC (0.5-12 kHz) to the median and ulnar nerves. Individual pain threshold was determined by gradual increase of stimulation amplitude. Subjects then performed a force-matching task by producing grip forces up to the maximal voluntary contraction level with and without application of tHFAC below the pain threshold. MAIN RESULTS: Pain threshold current amplitude increased linearly with stimulation frequency. Statistical analysis showed that both stimulation frequency and charge injected per phase had significant effects (p  < 0.05) on grip force reduction. At the group level, application of tHFAC below pain threshold reduced grip force by a maximum of 40.7% ± 8.1%. Baseline grip force trials interspersed between tHFAC trials showed consistent grip force, indicating that fatigue was not a factor in force reduction. SIGNIFICANCE: Our results demonstrate the effectiveness of tHFAC at reducing muscle force when applied below the pain threshold, suggesting its potential clinical viability. Future studies are necessary to further elucidate the mechanism of force reduction before clinical application.

7.
Yonsei Med J ; 60(7): 604-610, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31250573

RESUMO

PURPOSE: This study aimed to determine the prognostic value of new quantitative parameters of ¹8F-fluorodeoxyglucose positron emission tomography/computed tomography (¹8F-FDG PET/CT), including metabolic tumor volume (MTV), in patients with locally advanced and metastatic gallbladder cancer (GBC). MATERIALS AND METHODS: In total, 83 patients initially diagnosed with locally advanced and metastatic GBC and who underwent ¹8F-FDG PET/CT at the time of initial diagnosis were retrospectively reviewed. The metabolic volume-based PET parameters of primary tumors and metastatic lesions were measured, including maximum and average standardized uptake values (SUV), MTV, and total lesion glycolysis. An overall survival (OS) analysis was performed using the Kaplan-Meier method with PET and clinical parameters. A Cox proportional hazards regression analysis was performed to determine independent prognostic factors. RESULTS: In univariate analysis, pathologic differentiation (p<0.001), performance status (PS; p=0.003), C-reactive protein (CRP) level (p=0.009), and PET-related SUVmt max (the highest SUV among the metastatic lesions) (p=0.040) and MTVtotal (the sum of the MTVs of both the primary and metastatic lesions) (p=0.031), were significant for OS. In multivariate analysis, MTVtotal (hazard ratio: 2.07; 95% confidence interval: 1.23-3.48; p=0.006) remained significant for the prediction of OS, as did differentiation (p=0.001), PS (p=0.001), and CRP (p=0.039). CONCLUSION: In locally advanced and metastatic GBC, volume-based PET/CT parameters of the total tumor burden of malignancy, such as MTVtotal, were found to be useful for the identification of patients with poor prognosis.


Assuntos
Fluordesoxiglucose F18 , Neoplasias da Vesícula Biliar/metabolismo , Neoplasias da Vesícula Biliar/patologia , Glicólise , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Carga Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos
8.
Cancer Res Treat ; 51(4): 1578-1588, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30999721

RESUMO

PURPOSE: Temsirolimus is effective in the treatment for metastatic non-clear cell renal cell carcinoma (nccRCC) with poor prognosis. We aim to investigate the efficacy and tolerability of temsirolimus in treatment of naïve Asian patients with metastatic/recurrent nccRCC. Materials and Methods: From January 2008 to July 2017, data of treatment-naïve, metastatic/recurrent nccRCC patients, who were treated with temsirolimus according to the standard protocol, were collected. The primary end-point was progression-free survival (PFS). Secondary end points were overall survival (OS), objective response rate (ORR), and tolerability of temsirolimus. RESULTS: Forty-four metastatic/recurrent nccRCC patients, 10 from prospective and 34 from retrospective groups, were enrolled; 24 patients (54%) were papillary type, and other histology subtypes included 11 chromophobes (25%), two collecting ducts (5%), one Xp11.2 translocation (2%), and six others (14%). The median PFS and OS were 7.6 months and 17.6 months, res-pectively. ORR was 11% and disease control rate was 83%. Patients with prior nephrectomy had longer PFS (hazard ratio [HR], 0.16; 95% confidence interval [CI], 0.06 to 0.42; p < 0.001) and OS (HR, 0.15; 95% CI, 0.05 to 0.45; p < 0.001). Compared to favorable/intermediate prognosis group, poor prognosis group had shorter median PFS (4.7 months vs. 7.6 months [HR, 2.91; 95% CI, 1.39 to 6.12; p=0.005]) and median OS (9.2 months vs. 17.6 months [HR, 2.84; 95% CI, 1.23 to 6.56; p=0.015]). CONCLUSION: Temsirolimus not only benefits poor-risk nccRCC patients, but it is also effective in favorable or intermediate-risk group in Asians. Temsirolimus was well-tolerated with manageable adverse events.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Sirolimo/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/tratamento farmacológico , Estudos Prospectivos , República da Coreia , Estudos Retrospectivos , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
9.
Arch Phys Med Rehabil ; 100(10): 1907-1915, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31009599

RESUMO

OBJECTIVE: To propose an artificial intelligence (AI)-based decision-making rule in modified Ashworth scale (MAS) that draws maximum agreement from multiple human raters and to analyze how various biomechanical parameters affect scores in MAS. DESIGN: Prospective observational study. SETTING: Two university hospitals. PARTICIPANTS: Hemiplegic adults with elbow flexor spasticity due to acquired brain injury (N=34). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Twenty-eight rehabilitation doctors and occupational therapists examined MAS of elbow flexors in 34 subjects with hemiplegia due to acquired brain injury while the MAS score and biomechanical data (ie, joint motion and resistance) were collected. Nine biomechanical parameters that quantify spastic response described by the joint motion and resistance were calculated. An AI algorithm (or artificial neural network) was trained to predict the MAS score from the parameters. Afterwards, the contribution of each parameter for determining MAS scores was analyzed. RESULTS: The trained AI agreed with the human raters for the majority (82.2%, Cohen's kappa=0.743) of data. The MAS scores chosen by the AI and human raters showed a strong correlation (correlation coefficient=0.825). Each biomechanical parameter contributed differently to the different MAS scores. Overall, angle of catch, maximum stretching speed, and maximum resistance were the most relevant parameters that affected the AI decision. CONCLUSIONS: AI can successfully learn clinical assessment of spasticity with good agreement with multiple human raters. In addition, we could analyze which factors of spastic response are considered important by the human raters in assessing spasticity by observing how AI learns the expert decision. It should be noted that few data were collected for MAS3; the results and analysis related to MAS3 therefore have limited supporting evidence.


Assuntos
Encefalopatias/fisiopatologia , Articulação do Cotovelo/fisiopatologia , Hemiplegia/fisiopatologia , Espasticidade Muscular/fisiopatologia , Exame Neurológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
10.
Complement Ther Med ; 43: 312-318, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30935551

RESUMO

OBJECTIVES: This study aimed to compare the amount of deep tissue pressure and muscle relaxation between a soft inflatable rubber ball (SIRB) and a hard massage ball (HMB). DESIGN: Crossover experimental design study. INTERVENTIONS: Thirty participants with neck pain (age: 65.9 ± 3.4, Neck Disability Index score: 34.0% ± 15.2) pillowed a SIRB or an HMB beneath the suboccipital region in the supine position. For the baseline condition, participants pillowed a foam block without a ball. MAIN OUTCOME MEASURES: To quantify the amount of deep-tissue pressure by a ball, compressed soft tissue thickness was measured with lateral cervical radiographs. To assess muscle relaxation, the amount of muscle tension was determined using electromyography of the sternocleidomastoid and upper trapezius muscles. To monitor the cervical lordosis in each condition, the extension angles of the cervical vertebrae were quantified using the relative rotation angles. RESULTS: The compressed soft tissue thickness in the SIRB condition was significantly lower than that in the HMB condition. The normalised muscle activities exhibited that right sternocleidomastoid muscle activity in the HMB condition was significantly higher than that in the baseline and SIRB conditions. In the SIRB and HMB conditions, Numeric Rating Scale for pain was 0.2 ± 0.5 and 5.2 ± 1.4, respectively. CONCLUSIONS: Our findings demonstrate that a SIRB is more advantageous than an HMB for pressing the soft tissue deeply. This finding would be related to reduced muscle tension and discomfort in the SIRB condition when compared with the HMB condition.


Assuntos
Massagem/métodos , Síndromes da Dor Miofascial/terapia , Cervicalgia/terapia , Idoso , Vértebras Cervicais/fisiopatologia , Estudos Cross-Over , Feminino , Humanos , Masculino , Relaxamento Muscular/fisiologia , Tono Muscular/fisiologia , Músculos do Pescoço/fisiopatologia , Limiar da Dor/fisiologia , Pressão , Amplitude de Movimento Articular/fisiologia , Músculos Superficiais do Dorso/fisiopatologia , Pontos-Gatilho/fisiopatologia
11.
Oncology ; 96(2): 59-69, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30336470

RESUMO

BACKGROUND: We retrospectively investigated the treatment outcomes of second-line treatment with pazopanib or gemcitabine/docetaxel in patients with advanced soft tissue sarcoma (STS). METHODS: Ninety-one patients who were treated with pazopanib or gemcitabine/docetaxel for advanced STS between 1995 and 2015 were analyzed. RESULTS: Forty-six and 45 patients received pazopanib and gemcitabine/docetaxel, respectively. The median progression-free survival for the group treated with pazopanib was 4.5 months compared with 3.0 months for the gemcitabine/docetaxel group (p = 0.593). The median overall survival for the group treated with pazopanib was 12.6 months compared with 14.2 months for the gemcitabine/docetaxel group (p = 0.362). The overall response rates (ORRs) were 6.5 and 26.7% in the pazopanib and gemcitabine/docetaxel groups, respectively. The following parameters had ORRs favoring gemcitabine/docetaxel: age ≥50 years (31.6 vs. 2.9%, p = 0.006), histologic grade 1-2 (40.9 vs. 0%, p = 0.001), and poor first-line treatment response (23.3 vs. 3.0%, p = 0.022). Gemcitabine/docetaxel was associated with better ORRs for the following histologic subtypes: leiomyosarcoma (p = 0.624), malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma (p = 0.055), and angiosarcoma (p = 0.182). However, the ORR of synovial sarcoma favored pazopanib (p = 0.99). CONCLUSIONS: The efficacies of pazopanib and gemcitabine/docetaxel as second-line treatments after doxorubicin or ifosfamide failure differed among clinical and histologic subgroups and appeared to facilitate a more personalized treatment approach for advanced STS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Pirimidinas/uso terapêutico , Neoplasias de Tecidos Moles/tratamento farmacológico , Sulfonamidas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Docetaxel/administração & dosagem , Docetaxel/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pirimidinas/efeitos adversos , Estudos Retrospectivos , Neoplasias de Tecidos Moles/patologia , Sulfonamidas/efeitos adversos , Adulto Jovem
12.
Cancer Res Treat ; 51(2): 819-831, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30282452

RESUMO

PURPOSE: Identification of biomarkers to predict recurrence risk is essential to improve adjuvant treatment strategies in stage II/III gastric cancer patients. This study evaluated biomarkers for predicting survival after surgical resection. Materials and Methods: This post-hoc analysis evaluated patients from the CLASSIC trial who underwent D2 gastrectomy with or without adjuvant chemotherapy (capecitabine plus oxaliplatin) at the Yonsei Cancer Center. Tumor expressions of thymidylate synthase (TS), excision repair cross-complementation group 1 (ERCC1), and programmed death-ligand 1 (PD-L1) were evaluated by immunohistochemical (IHC) staining to determine their predictive values. RESULTS: Among 139 patients, IHC analysis revealed high tumor expression of TS (n=22, 15.8%), ERCC1 (n=23, 16.5%), and PD-L1 (n=42, 30.2%) in the subset of patients. Among all patients, high TS expression tended to predict poor disease-free survival (DFS; hazard ratio [HR], 1.80; p=0.053), whereas PD-L1 positivity was associated with favorable DFS (HR, 0.33; p=0.001) and overall survival (OS; HR, 0.38; p=0.009) in multivariate Cox analysis. In the subgroup analysis, poor DFS was independently predicted by high TS expression (HR, 2.51; p=0.022) in the adjuvant chemotherapy subgroup (n=66). High PD-L1 expression was associated with favorable DFS (HR, 0.25; p=0.011) and OS (HR, 0.22; p=0.015) only in the surgery-alone subgroup (n=73). The prognostic impact of high ERCC1 expression was not significant in the multivariate Cox analysis. CONCLUSION: This study shows that high TS expression is a predictive factor for worse outcomes on capecitabine plus oxaliplatin adjuvant chemotherapy, whereas PD-L1 expression is a favorable prognostic factor in locally advanced gastric cancer patients.


Assuntos
Biomarcadores Tumorais , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Adulto , Idoso , Antígeno B7-H1/metabolismo , Ensaios Clínicos Fase III como Assunto , Terapia Combinada , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia
13.
Micromachines (Basel) ; 9(12)2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30567359

RESUMO

The skeletal muscle occupies about 40% mass of the human body and plays a significant role in the skeletal movement control. Skeletal muscle injury also occurs often and causes pain, discomfort, and functional impairment in daily living. Clinically, most studies observed the recovery phenomenon of muscle by massage or electrical stimulation, but there are limitations on quantitatively analyzing the effects on recovery. Although additional efforts have been made within in vitro biochemical research, some questions still remain for effects of the different cell microenvironment for recovery. To overcome these limitations, we have developed a microfluidic system to investigate appropriate conditions for repairing skeletal muscle injury. First, the muscle cells were cultured in the microfluidic chip and differentiated to muscle fibers. After differentiation, we treated hydrogen peroxide and 18% axial stretch to cause chemical and physical damage to the muscle fibers. Then the damaged muscle fibers were placed under the cyclic stretch condition to allow recovery. Finally, we analyzed the damage and recovery by quantifying morphological change as well as the intensity change of intracellular fluorescent signals and showed the skeletal muscle fibers recovered better in the cyclic stretched condition. In total, our in situ generation of muscle damage and induction recovery platform may be a key system for investigating muscle recovery and rehabilitation.

14.
Gait Posture ; 65: 157-162, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30510358

RESUMO

Background: Patients with brain injuries such as Parkinson's disease or stroke exhibit abnormal gait characteristics especially during gait transitions such as step initiation and turning. Since such transitions could precipitate falls and resultant injuries, evaluation and rehabilitation of non-steady state gait in those patients are important. Whereas body weight supported treadmill training (BWSTT) provides a safe and controlled environment for gait training, it is unable to adequately train for gait transitions since the typical linear treadmill does not allow for changes in walking direction and natural fluctuations in speed. Research question: This paper verifies if the suggested virtual reality (VR) based walking interface combined with the unidirectional treadmill can stimulate the user to initiate turning gait. Methods: To validate whether initiation of turning was successfully achieved with the proposed walking system, we developed the VR-based walking interface combined with the self-paced treadmill and compared kinematics, kinetics, and muscle activation levels during the VR-based turning and over ground (OG) turning as well as between straight walking and turning within conditions. Results: Despite walking on a linear treadmill, subjects showed significant increases in head rotation, pelvic rotation, right hip abduction, left hip adduction, foot progression, medial-lateral ground reaction forces, right medial hamstring activation level, and changes in step width during the VR turn compared to straight walking. Significance: The developed VR-based turning interface can provide a safe and controlled environment for assessment of turning in healthy controls and may have a potential for assessment and training in patients with neurological disorders.


Assuntos
Teste de Esforço , Marcha/fisiologia , Realidade Virtual , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Pé/fisiologia , Cabeça/fisiologia , Quadril/fisiologia , Humanos , Cinética , Masculino , Pelve/fisiologia , Rotação , Adulto Jovem
15.
Front Neurol ; 9: 863, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30416478

RESUMO

We investigated the muscle alterations related to spasticity in stroke quantitatively using a portable manual spasticity evaluator. Methods: Quantitative neuro-mechanical evaluations under controlled passive elbow stretches in stroke survivors and healthy controls were performed in a research laboratory of a rehabilitation hospital. Twelve stroke survivors and nine healthy controls participated in the study. Spasticity and catch angle were evaluated at 90°/s and 270°/s with the velocities controlled through real-time audiovisual feedback. The elbow range of motion (ROM), stiffness, and energy loss were determined at a slow velocity of 30°/s. Four-dimensional measures including joint position, torque, velocity and torque change rate were analyzed jointly to determine the catch angle. Results: The catch angle was dependent on the stretch velocity and occurred significantly later with increasing velocity (p < 0.001), indicating position dependence of spasticity. The higher resistance felt by the examiner at the higher velocity was also due to more extreme joint position (joint angle) since the spastic joint was moved significantly further to a stiffer elbow position with the higher velocity. Stroke survivors showed smaller ROM (p < 0.001), higher stiffness (p < 0.001), and larger energy loss (p = 0.005). Compared to the controls, stroke survivors showed increased reflex excitability with higher reflex-mediated torque (p < 0.001) and at higher velocities (p = 0.02). Conclusion: Velocity dependence of spasticity is partially due to joint angle position dependence with the joint moved further (to a stiffer position where higher resistance was felt) at a higher velocity. The "4-dimensional characterization" including the joint angle, velocity, torque, and torque change rate provides a systematic tool to characterize catch angle and spasticity quantitatively.

16.
J Anal Methods Chem ; 2018: 7832987, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30420937

RESUMO

We developed a new method for MALDI-TOF MS detection of N-glycans derived from human serum. The synergistic combination of microwave-assisted Girard T derivatization, solid-phase extraction desalting, and an ionic liquid matrix (2, 5-dihydroxybenzoic acid/aniline) (GT-SPE-DHB/An) allowed of more sensitive N-glycans detection than a conventional ionic liquid matrix in MALDI-TOF MS. The superior sensitivity of our method was confirmed by the number of assigned N-glycans in 900-2,000 m/z range. Using our GT-SPE-DHB/An method, we were successfully able to assign 31 glycans. However, with the established method, i.e., DHB/An method, only 15 glycans were assigned. To the best of our knowledge, this GT-SPE-DHB/An method is the first to combine cationic derivatization of N-glycan and ionic liquid matrix for N-glycan analysis in MALDI-TOF MS.

18.
Front Neurorobot ; 12: 38, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30100871

RESUMO

As the number of people suffering from shoulder movement disabilities increases, there is a rising demand for shoulder rehabilitation. The natural motion of the shoulder joint [glenohumeral (GH) joint] includes not only three-degrees-of-freedom (DOF) rotation but also three-DOF translation of the joint center due to simultaneous motion of the shoulder girdle. If the motion of the shoulder girdle is restricted, then the arm cannot be raised above a certain posture. This paper presents a passive shoulder joint tracking device that allows three-DOF translation of the shoulder joint while compensating for gravity. The single-DOF vertical tracker with a constant-force spring compensates for the gross weight of the user's arm, the upper limb rehabilitation device, and the tracker itself while allowing vertical tracking motion. The two-DOF horizontal tracker consists of two linear guides arranged perpendicular to each other. The tracker freely follows the shoulder joint in the horizontal plane. The effect of using the passive shoulder joint tracking device was evaluated by means of experiments by combining two popular commercial upper limb rehabilitation apparatuses with the proposed tracker. Nineteen subjects (8 healthy persons and 11 patients with shoulder impairments) participated in the evaluation study. The movement of the GH joint and the interactive force between the subject and the commercial rehabilitation device were analyzed when subjects made the following shoulder movements: flexion/extension and abduction/adduction. The improved tracker allowed a greater range of motion and reduced interaction. The tracker can be combined with existing commercial rehabilitation devices for more natural shoulder movement during rehabilitation tasks.

19.
J Neuroeng Rehabil ; 15(1): 80, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30126438

RESUMO

BACKGROUND: Innovative technical approaches to controlling undesired sensory and motor activity, such as hyperalgesia or spasticity, may contribute to rehabilitation techniques for improving neural plasticity in patients with neurologic disorders. To date, transcutaneous electrical stimulation has used low frequency pulsed currents for sensory inhibition and muscle activation. Yet, few studies have attempted to achieve motor nerve inhibition using transcutaneous electrical stimulation. This study aimed to develop a technique for transcutaneous electrical nerve inhibition (TENI) using medium-frequency alternating current (MFAC) to suppress both sensory and motor nerve activity in humans. METHODS: Surface electrodes were affixed to the skin of eight young adults to stimulate the median nerve. Stimulation intensity was increased up to 50% and 100% of the pain threshold. To identify changes in sensory perception by transcutaneous MFAC (tMFAC) stimulation, we examined tactile and pressure pain thresholds in the index and middle fingers before and after stimulation at 10 kHz. To demonstrate the effect of tMFAC stimulation on motor inhibition, stimulation was applied while participants produced flexion forces with the index and middle fingers at target forces (50% and 90% of MVC, maximum voluntary contraction). RESULTS: tMFAC stimulation intensity significantly increased tactile and pressure pain thresholds, indicating decreased sensory perception. During the force production task, tMFAC stimulation with the maximum intensity immediately reduced finger forces by ~ 40%. Finger forces recovered immediately after stimulation cessation. The effect on motor inhibition was greater with the higher target force (90% MVC) than with the lower target (50% MVC). Also, higher tMFAC stimulation intensity provided a greater inhibition effect on both sensory and motor nerve activity. CONCLUSION: We found that tMFAC stimulation immediately inhibits sensory and motor activity. This pre-clinical study demonstrates a novel technique for TENI using MFAC stimulation and showed that it can effectively inhibit both sensory perception and motor activity. The proposed technique can be combined with existing rehabilitation devices (e.g., a robotic exoskeleton) to inhibit undesired sensorimotor activities and to accelerate recovery after neurologic injury.


Assuntos
Limiar Sensorial/fisiologia , Estimulação Elétrica Nervosa Transcutânea/métodos , Adulto , Feminino , Humanos , Masculino , Nervo Mediano/fisiologia , Atividade Motora/fisiologia , Estimulação Elétrica Nervosa Transcutânea/instrumentação
20.
Ann Surg Oncol ; 25(11): 3222-3230, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30051367

RESUMO

BACKGROUND: There is increasing interest in the influence of body composition on oncological outcomes. We evaluated the role of skeletal muscle and fat among patients with gastric cancer (GC) who underwent gastrectomy with or without adjuvant chemotherapy, as well as those changes' associations with survival outcomes. METHODS: The present study evaluated 136 patients with GC who were enrolled in the CLASSIC Trial at Yonsei Cancer Center. Baseline body compositions including skeletal muscle area, Hounsfield units (HU), visceral fat area, and subcutaneous fat area were measured by preoperative computed tomography (CT). CT before and after the gastrectomy were used to determine the 6-month relative changes in body composition parameters. Continuous variables were dichotomized according to the best cutoff values by Contal and O'Quigley method. RESULTS: Seventy-three patients (53.7%) underwent surgery alone, and 63 patients (46.3%) underwent surgery followed by adjuvant chemotherapy. The baseline body composition parameters were not associated with disease-free survival (DFS) or overall survival (OS). Except for the HU, the marked loss of muscle, visceral fat, or subcutaneous fat significantly predicted shorter DFS and OS. Patients with a marked loss in at least one significant body composition parameter had significantly shorter DFS (hazard ratio 2.9, 95% confidence interval 1.7-4.8, P < 0.001) and OS (hazard ratio 2.9, 95% confidence interval 1.7-5.0, P < 0.001). CONCLUSIONS: Marked loss in body composition parameters significantly predicted shorter DFS and OS among patients with GC who underwent gastrectomy. Postoperative nutrition and active healthcare interventions could improve the prognosis of these GC patients.


Assuntos
Adenocarcinoma/mortalidade , Gastrectomia/efeitos adversos , Gordura Intra-Abdominal/patologia , Complicações Pós-Operatórias , Sarcopenia/mortalidade , Neoplasias Gástricas/mortalidade , Gordura Subcutânea/patologia , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Adulto , Idoso , Composição Corporal , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Sarcopenia/etiologia , Sarcopenia/patologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Adulto Jovem
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