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1.
Neurorehabil Neural Repair ; 35(10): 915-928, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34455852

RESUMO

Background. Poststroke individuals use their paretic arms less often than expected in daily life situations, even when motor recovery is scored highly in clinical tests. Real-world environments are often unpredictable and require the ability to multitask and make decisions about rapid and accurate arm movement adjustments. Objective. To identify whether and to what extent cognitive-motor deficits in well-recovered individuals with stroke affect the ability to rapidly adapt reaching movements in changing cognitive and environmental conditions. Methods. Thirteen individuals with mild stroke and 11 healthy controls performed an obstacle avoidance task in a virtual environment while standing. Subjects reached for a virtual juice bottle with their hemiparetic arm as quickly as possible under single- and dual-task conditions. In the single-task condition, a sliding glass door partially obstructed the reaching path of the paretic arm. A successful trial was counted when the subject touched the bottle without the hand colliding with the door. In the dual-task condition, subjects repeated the same task while performing an auditory-verbal working memory task. Results. Individuals with stroke had significantly lower success rates than controls in avoiding the moving door in single-task (stroke: 51.8 ± 21.2%, control: 70.6 ± 12.7%; P = .018) and dual-task conditions (stroke: 40.0 ± 27.6%, control: 65.3 ± 20.0%; P = .015). Endpoint speed was lower in stroke subjects for successful trials in both conditions. Obstacle avoidance deficits were exacerbated by increased cognitive demands in both groups. Individuals reporting greater confidence using their hemiparetic arm had higher success rates. Conclusion. Clinically well-recovered individuals with stroke may have persistent deficits performing a complex reaching task.

2.
Ultrason Sonochem ; 66: 105116, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32252011

RESUMO

The current work is a "first of a kind" report on the feasibility and efficacy of hydrodynamic cavitation integrated Advanced Oxidation Processes (AOP's) towards treatment of a real life greywater stream in form of kitchen wastewater. The work has been carried out in a sequential manner starting with geometry optimization of orifice plate (cavitating device) followed by studying the effects of inlet pressure, pH, effluent dilution ratio on degradation of TOC and COD. Under optimized conditions of pH 3, 4 bar pressure, TOC and COD reduction of 18.23 and 25% were obtained using HC for a period of 120 min. To improve the performance of HC, further studies were carried out by integrating H2O2and O3with HC. Using 5 g/h optimum dosage of H2O2, 87.5% reduction in COD was obtained beyond which it started decreasing. Moreover, integrating O3(57.5% reduction in COD) increased the treatment cost. However, a hybrid process (HC + H2O2 + O3) yielded 76.26 and 98.25% reductions in TOC and COD within60 min.The energetics of all the processes and the treatment costs were studied in detail and it was concluded that combined process of HC + H2O2 + O3surpassed by far the performances of HC + H2O2and HC + O3.

3.
Ultrason Sonochem ; 50: 126-137, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30245202

RESUMO

High fluoride content in the natural water sources is a serious matter of concern and adsorption is recommended as one of the most convenient, affordable and widely applied defluorination technologies. In this study, a novel composite was synthesized by impregnating magnesium (Mg), manganese (Mn) and zirconium (Zr) on powdered activated carbon (AC) for effective fluoride adsorption and the synthesis was made using sonochemical method. The characterization of the prepared adsorbent AC-Mg-Mn-Zr along with individual metal composites AC-Zr, AC-Mg and AC-Mn were done by SEM, EDX, FTIR, XRD and BET analysis to understand the major functional bonds, and changes in surface chemistry after adsorption. The mechanism of the process was discussed through major reactions involved for individual metals. Due to high point of zero charge (pHPZC = 11.9), the adsorbent was able to remove more than 96% of fluoride consistently with only 1 g/L of optimum adsorbent dosage for a wide pH range (2 to 10). The maximum adsorption capacity obtained was 26.27 mg/g within an equilibrium time of 3 h. More than 96% energy saving was achieved in the sonochemical synthesis route compared to conventional precipitation method of synthesis.

4.
Arch Phys Med Rehabil ; 100(4): 751-768, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30452892

RESUMO

OBJECTIVES: (1) To determine the effect of transcutaneous electrical nerve stimulation (TENS) on poststroke spasticity. (2) To determine the effect of different parameters (intensity, frequency, duration) of TENS on spasticity reduction in adults with stroke. (3) To determine the influence of time since stroke on the effectiveness of TENS on spasticity. DATA SOURCES: PubMed, PEDro, CINAHL, Web of Science, CENTRAL, and EMBASE databases were searched from inception to March 2017. STUDY SELECTION: Randomized controlled trial (RCT), quasi-RCT, and non-RCT were included if (1) they evaluated the effects of TENS for the management of spasticity in participants with acute or subacute or chronic stroke using clinical and neurophysiological tools; and (2) TENS was delivered either alone or as an adjunct to other treatments. DATA EXTRACTION: Two authors independently screened and extracted data from 15 of the 829 studies retrieved through the search using a pilot tested pro forma. Disagreements were resolved through discussion with other authors. Quality of studies was assessed using Cochrane risk of bias criteria. DATA SYNTHESIS: Meta-analysis was performed using a random-effects model that showed (1) TENS along with other physical therapy treatments was more effective in reducing spasticity in the lower limbs compared to placebo TENS (SMD -0.64; 95% confidence interval [95% CI], -0.98 to -0.31; P=.0001; I2=17%); and (2) TENS, when administered along with other physical therapy treatments, was effective in reducing spasticity when compared to other physical therapy interventions alone (SMD -0.83; 95% CI, -1.51 to -0.15; P=.02; I2=27%). There were limited studies to evaluate the effectiveness of TENS for upper limb spasticity. CONCLUSION: There is strong evidence that TENS as an adjunct is effective in reducing lower limb spasticity when applied for more than 30 minutes over nerve or muscle belly in chronic stroke survivors (review protocol registered at PROSPERO: CRD42015020151).


Assuntos
Espasticidade Muscular/reabilitação , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/complicações , Estimulação Elétrica Nervosa Transcutânea/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Resultado do Tratamento
5.
Physiother Res Int ; 24(1): e1756, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30403320

RESUMO

OBJECTIVE: To identify and compare factors influencing the use of standardized outcome measures by neurological physical therapists working in representative developed (Canada) and developing (India) countries. METHODS: A self-administered web-based questionnaire on facilitators and barriers to using neurological outcome measures was sent by email to neurological physical therapists in Canada and India. Frequencies of responses to each question were computed. Differences between countries were assessed using two-proportion z test. RESULTS: Of 317 respondents, the use of standardized outcome measures was higher for Indian (96.7%) compared with Canadian physical therapists (89.2%). Among the most highly reported facilitators, three were common for both countries (known validity and reliability, outcome measures learned in professional training, and recommended in clinical practice guidelines). Three highly reported barriers were also common for India and Canada (lack of time, relying on judgement for clinical decisions, and unavailability of the assessment tools). Nevertheless, there were differences in the percentages of barriers and facilitators between countries. CONCLUSION: Understanding the factors influencing the uptake of outcome measures among neurological physical therapists working in a developed (Canada) and a developing country (India) can help identify whether strategies should or should not be modified to facilitate knowledge translation in different geographical, professional, or social contexts.


Assuntos
Atitude do Pessoal de Saúde , Países em Desenvolvimento , Fisioterapeutas/normas , Modalidades de Fisioterapia/normas , Especialidade de Fisioterapia/normas , Canadá , Competência Clínica/normas , Países Desenvolvidos , Eficiência Organizacional/normas , Humanos , Índia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Avaliação de Processos em Cuidados de Saúde/organização & administração , Reprodutibilidade dos Testes , Inquéritos e Questionários , Pesquisa Médica Translacional
6.
Ultrason Sonochem ; 45: 65-77, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29705326

RESUMO

Environmental concern associated with the side effects of high fluoride content in ground water and surface water has prompted the researchers to look for an efficient, convenient and easy method. Considering the potential of a good adsorbent, present study reports the synthesis of a composite by impregnating zirconium on powdered activated carbon (AC) using ultrasound as the tool for synthesis and applying it for fluoride adsorption from water. The nature of the composite was determined through characterization by scanning electron microscopy (SEM), energy dispersive Xray (EDX), Xray diffraction (XRD), N2 adsorption analysis (BET) and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The pHpzc (point of zero charge) of the adsorbent was found to be 5.03; with the optimum pH obtained at 4 for adsorption of strong electronegative fluoride ions. The initial fluoride concentration was varied from 2.5 up to 20 mg.L-1 and the maximum adsorption capacity of 5 mg.g-1 was obtained. A maximum fluoride removal of 94.4% was obtained for an initial concentration of 2.5 mg.L-1 within an equilibrium time of 180 min. The adsorption isotherm followed the Langmuir isotherm model indicating a monolayer adsorption process and the adsorption kinetics followed pseudo second order model. The effects of various coexisting ions (HCO3-, NO3-, SO42-, Cl-) commonly present in the water were found to have negligible impact on the process performance. Conducting the adsorption-desorption studies for five consecutive cycles for an initial fluoride concentration of 10 mg.L-1, the removal efficiency reduced from 86.2 to 32.6%. The ultrasonic method provided an easy route to synthesize the composite in less time and significantly reduced energy consumption by more than 96% compared to the conventional method.

7.
Neurorehabil Neural Repair ; 32(2): 175-186, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29554848

RESUMO

Kinematic redundancy of the human body provides abundant movement patterns to accomplish the same motor goals (motor equivalence). Compensatory movement patterns such as excessive trunk displacement in stroke subjects during reaching can be viewed as a consequence of the motor equivalent process to accomplish a task despite limited available ranges in some joints. However, despite compensations, the ability to adapt reaching performance when perturbations occur may still be limited when condition-specific changes of joint angles are required. We addressed this hypothesis in individuals with and without stroke for reaching a target placed beyond arm reach in standing while flexing the hips (free-hip condition). In randomly selected trials, hip flexion was unexpectedly blocked, forcing subjects to take a step (blocked-hip condition). In additional trials, subjects took an intentional step while reaching the target (intentional-step condition). In blocked-hip trials, healthy subjects maintained smooth and precise endpoint trajectories by adapting temporal and spatial interjoint coordination to neutralize the effect of the perturbation. However, the ability to produce motor equivalent solutions was reduced in subjects with stroke, evidenced by substantial overshoot errors in endpoint position, reduced movement smoothness and less adaptive elbow-shoulder interjoint coordination. Movement adaptability was more limited in stroke subjects who used more compensatory movements for unperturbed reaching. Results suggest that subjects with mild-to-moderate stroke only partially adapted arm joint movements to maintain reaching performance. Therapeutic efforts to enhance the ability of individuals with stroke to find a larger number of task-relevant motor solutions (adaptability) may improve upper limb recovery.


Assuntos
Adaptação Fisiológica/fisiologia , Braço/fisiopatologia , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Idoso , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular/fisiologia
8.
Exp Brain Res ; 236(2): 381-398, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29164285

RESUMO

This study addresses the question of how posture and movement are oriented with respect to the direction of gravity. It is suggested that neural control levels coordinate spatial thresholds at which multiple muscles begin to be activated to specify a referent body orientation (RO) at which muscle activity is minimized. Under the influence of gravity, the body is deflected from the RO to an actual orientation (AO) until the emerging muscle activity and forces begin to balance gravitational forces and maintain body stability. We assumed that (1) during quiet standing on differently tilted surfaces, the same RO and thus AO can be maintained by adjusting activation thresholds of ankle muscles according to the surface tilt angle; (2) intentional forward body leaning results from monotonic ramp-and-hold shifts in the RO; (3) rhythmic oscillation of the RO about the ankle joints during standing results in body swaying. At certain sway phases, the AO and RO may transiently overlap, resulting in minima in the activity of multiple muscles across the body. EMG kinematic patterns of the 3 tasks were recorded and explained based on the RO concept that implies that these patterns emerge due to referent control without being pre-programmed. We also confirmed the predicted occurrence of minima in the activity of multiple muscles at specific body configurations during swaying. Results re-affirm previous rejections of model-based computational theories of motor control. The role of different descending systems in the referent control of posture and movement in the gravitational field is considered.


Assuntos
Gravitação , Movimento/fisiologia , Orientação/fisiologia , Postura/fisiologia , Adulto , Análise de Variância , Eletromiografia , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto Jovem
9.
Physiother Can ; 69(4): 303-312, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30369697

RESUMO

Purpose: The purpose of this study was to understand current trends in rehabilitation practice regarding spasticity assessment and treatment. Method: The clinical practices of Canadian physiotherapists and occupational therapists in assessing and treating spasticity were investigated using a self-administered, Web-based questionnaire (cross-sectional design). Experienced clinicians developed the questionnaire, which surveyed socio-demographic characteristics, work environment, and clinician satisfaction with spasticity assessments and preferences for treatment. Results: A total of 317 clinicians (204 physiotherapists and 113 occupational therapists) completed the questionnaire. The majority of participants reported that using valid and reliable outcome measures to assess spasticity was important (91.1%). Most clinicians indicated using a combination of spasticity assessments, and their level of satisfaction with these assessments was very high. All clinicians believed that spasticity should be evaluated by rehabilitation professionals, and most indicated that it should be assessed by more than one professional. Although 83.8% indicated that spasticity should be tested on admission, a much lower percentage believed that it should be evaluated throughout rehabilitation. Most clinicians (92.2%) reported using multiple treatment modalities for spasticity. Conclusions: This study is the first to document clinicians' practices regarding spasticity assessment and treatment. A better understanding of current trends in physiotherapy and occupational therapy will help in tailoring strategies to improve practice.

10.
Neurorehabil Neural Repair ; 31(2): 133-146, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27542986

RESUMO

BACKGROUND: Upper limb (UL) poststroke hemiparesis commonly leads to chronic disability. Despite moderate-to-good clinical recovery, many patients with UL hemiparesis still do not fully use their arm in daily tasks. Decreased arm use may be related to deficits in performance of more complex movement than what is usually assessed clinically. OBJECTIVE: To identify differences between poststroke and nondisabled control subjects in making complex corrective movements to avoid an obstacle in the reaching path. METHODS: Subjects rapidly reached for a juice bottle on a refrigerator shelf with their hemiparetic or dominant (controls) arm viewed in a large-screen projected 3D virtual environment. In random trials, a sliding door partially obstructed the reaching path. A successful trial was one in which subjects touched the bottle without their arm or hand hitting the door. RESULTS: Fewer participants with stroke (12%) were successful at a 65% success rate in avoiding the door compared to controls (42%). Subjects with stroke also initiated corrections later (further) in the reaching path (100.7 ± 77.6 mm) compared to controls (51.6 ± 31.0 mm) resulting in a reduced margin of error. While both groups used similar endpoint movement strategies for obstructed reaching, subjects with stroke used less elbow and more trunk movement. Participants who reported being more confident using their hemiparetic arm had higher success rates. CONCLUSION: Arm movement deficits can be identified when complex tasks are evaluated. Deficits in higher-order motor function such as obstacle avoidance behavior may decrease actual arm use in individuals with mild-to-moderate hemiparesis and should be evaluated in routine clinical practice.


Assuntos
Aprendizagem da Esquiva , Atividade Motora , Paresia/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Extremidade Superior , Atividades Cotidianas/psicologia , Adaptação Psicológica , Idoso , Fenômenos Biomecânicos , Isquemia Encefálica/complicações , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/psicologia , Hemorragia Cerebral/complicações , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/psicologia , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Paresia/etiologia , Paresia/psicologia , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia , Extremidade Superior/fisiopatologia , Interface Usuário-Computador
11.
Phys Ther ; 96(5): 687-95, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26450971

RESUMO

BACKGROUND: Commonly used spasticity scales assess the resistance felt by the evaluator during passive stretching. These scales, however, have questionable validity and reliability. The tonic stretch reflex threshold (TSRT), or the angle at which motoneuronal recruitment begins in the resting state, is a promising alternative for spasticity measurement. Previous studies showed that spasticity and voluntary motor deficits after stroke may be characterized by a limitation in the ability of the central nervous system to regulate the range of the TSRT. OBJECTIVE: The study objective was to assess interevaluator reliability for TSRT plantar-flexor spasticity measurement. DESIGN: This was an interevaluator reliability study. METHODS: In 28 people after stroke, plantar-flexor spasticity was evaluated twice on the same day. Plantar-flexor muscles were stretched 20 times at different velocities assigned by a portable device. Plantar-flexor electromyographic signals and ankle angles were used to determine dynamic velocity-dependent thresholds. The TSRT was computed by extrapolating a regression line through dynamic velocity-dependent thresholds to the angular axis. RESULTS: Mean TSRTs in evaluations 1 and 2 were 66.0 degrees (SD=13.1°) and 65.8 degrees (SD=14.1°), respectively, with no significant difference between them. The intraclass correlation coefficient (2,1) was .851 (95% confidence interval=.703, .928). LIMITATIONS: The notion of dynamic stretch reflex threshold does not exclude the possibility that spasticity is dependent on acceleration, as well as on velocity; future work will study both possibilities. CONCLUSIONS: Tonic stretch reflex threshold interevaluator reliability for evaluating stroke-related plantar-flexor spasticity was very good. The TSRT is a reliable measure of spasticity. More information may be gained by combining the TSRT measurement with a measure of velocity-dependent resistance.


Assuntos
Espasticidade Muscular/fisiopatologia , Músculo Esquelético/fisiopatologia , Reflexo de Estiramento , Acidente Vascular Cerebral/fisiopatologia , Aceleração , Adulto , Idoso , Eletromiografia , Feminino , , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Variações Dependentes do Observador , Acidente Vascular Cerebral/complicações
12.
Restor Neurol Neurosci ; 33(3): 389-403, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26410581

RESUMO

PURPOSE: Motor and cognitive impairments are common and often coexist in patients with stroke. Although evidence is emerging about specific relationships between cognitive deficits and upper-limb motor recovery, the practical implication of these relationships for rehabilitation is unclear. Using a structured review and meta-analyses, we examined the nature and strength of the associations between cognitive deficits and upper-limb motor recovery in studies of patients with stroke. METHODS: Motor recovery was defined using measures of upper limb motor impairment and/or activity limitations. Studies were included if they reported on at least one measure of cognitive function and one measure of upper limb motor impairment or function. RESULTS: Six studies met the selection criteria. There was a moderate association (r = 0.43; confidence interval; CI:0.09- 0.68, p = 0.014) between cognition and overall arm motor recovery. Separate meta-analyses showed a moderately strong association between executive function and motor recovery (r = 0.48; CI:0.26- 0.65; p < 0.001), a weak positive correlation between attention and motor recovery (r = 0.25; CI:0.04- 0.45; p = 0.023), and no correlation between memory and motor recovery (r = 0.42; CI:0.16- 0.79; p = 0.14). CONCLUSION: These results imply that information on the presence of cognitive deficits should be considered while planning interventions for clients in order to design more personalized interventions tailored to the individual for maximizing upper-limb recovery.


Assuntos
Braço/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Atividades Cotidianas , Transtornos Cognitivos/etiologia , Humanos , Acidente Vascular Cerebral/complicações
13.
Clin Neurophysiol ; 124(4): 740-51, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23146713

RESUMO

OBJECTIVE: Muscle spasticity following stroke has been shown to result from limitations in the range of regulation of the tonic reflex spatial threshold (ST), i.e., the joint angle at which the stretch reflex begins to act due to descending and segmental influences on motoneurons. The purpose of this study was to determine whether spasticity due to stroke and rigidity due to parkinsonism can be discriminated based on the ST measure. METHODS: Elbow muscles were stretched at different velocities in healthy, stroke (spasticity) and parkinsonism (rigidity) subjects. The elbow angle at which muscle activation began for each stretch velocity (dynamic ST) and the velocity sensitivity of the ST were measured. Dynamic ST values extrapolated to zero velocity defined the tonic ST. RESULTS: Compared to healthy subjects, spasticity and rigidity were associated with a decrease in the range of central regulation of tonic STs. STs were hypersensitive in spastic muscles and either hypo- or inversely sensitive to stretch velocity in rigid muscles. CONCLUSIONS: ST characteristics discriminate between neurological deficits of muscle tone. SIGNIFICANCE: Results suggest that spasticity and rigidity result from deficits in descending facilitatory control combined with deficits in dynamic fusimotor or/and presynaptic control of Ia inputs to motoneurons.


Assuntos
Rigidez Muscular/fisiopatologia , Espasticidade Muscular/fisiopatologia , Reflexo de Estiramento/fisiologia , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Interpretação Estatística de Dados , Diagnóstico Diferencial , Cotovelo/fisiologia , Eletrodiagnóstico , Eletromiografia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Rigidez Muscular/diagnóstico , Rigidez Muscular/etiologia , Espasticidade Muscular/diagnóstico , Espasticidade Muscular/etiologia , Tono Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Paresia/fisiopatologia , Doença de Parkinson/complicações , Doença de Parkinson/fisiopatologia , Acidente Vascular Cerebral/complicações
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