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1.
J Acoust Soc Am ; 156(3): 1529-1542, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39235272

RESUMEN

Relative humidity, temperature, and wind along flight paths from a 10-year simulation are used to investigate the effects of the atmospheric conditions on sonic boom loudness generated by the pseudo-Concorde and a low-boom supersonic aircraft using an acoustic wave propagation tool. Global meteorological conditions are simulated using the chemistry-climate model EMAC with ECMWF reanalysis data. The results show that atmospheric conditions lead to a seasonal variation of the perceived level for a N-wave over 10 years of flights, whereas it is difficult to identify the seasonal variation for the low-boom aircraft because the distribution of perceived levels is widely spread. The dominant effect from atmospheric conditions during acoustic propagation is found for the low-boom aircraft cruising at an altitude of 14.478 km. The molecular relaxation effect is dominant for an overpressure reduction at 10 km but does not impact the pressure waveform below 8 km. At altitudes below 8 km, the thermoviscous absorption exclusively influences the variations in pressure rise time. Moreover, acoustic wave propagation through the turbulent field was simulated at a single location. Even though the acoustic wave passed through the same turbulent field in the summer and winter cases, the loudness on the ground differs between them.

2.
Spinal Cord ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271798

RESUMEN

STUDY DESIGN: Single institution observational study. OBJECTIVES: To investigate the ceiling and floor effects of the Berg Balance Scale (BBS), Mini-Balance Evaluation Systems Test (BESTest), and Brief-BESTest, as well as to determine the intra- and inter-rater reliabilities and minimal detectable change (MDC) of the Mini-BESTest and Brief-BESTest in patients with acute and subacute incomplete cervical spinal cord injury (SCI) classified as AIS D. SETTING: Advanced critical care center of our university hospital. METHODS: Twenty patients with incomplete cervical SCI who could stand without assistance were recruited. The floor and ceiling effects were evaluated by plotting histograms from the distribution of scores on the BBS, Mini-BESTest and Brief-BESTest, and calculating skewness. The Mini-BESTest and Brief-BESTest were evaluated and videotaped simultaneously, and intra- and inter-rater reliabilities were assessed. The MDC was also calculated. RESULTS: The skewness of the BBS was -1.57, and the full score was 35%, indicating a ceiling effect. However, no ceiling or floor effect was observed for the Mini-BESTest and the Brief-BESTest. Intraclass correlation coefficients for intra-rater and inter-rater reliabilities were 0.98 and 0.97 for the Mini-BESTest and Brief-BESTest, respectively. Individual item reliability was moderate or better for the Mini-BESTest and excellent or better for the Brief-BESTest. The MDC of total scores ranged 3.14-3.84 and 2.92-3.60 for the Mini-BESTest and Brief-BESTest, respectively. CONCLUSIONS: The Mini-BESTest and Brief-BESTest are reliable assessment tools for patients with acute and subacute incomplete SCI classified as AIS D. Clarified error ranges aid in estimating the treatment effect on balance abilities.

3.
Biomedicines ; 12(3)2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38540236

RESUMEN

It is well known that cortical damage may affect cognitive functions, whereas subcortical damage, especially brainstem stroke, would be far less likely to cause cognitive decline, resulting in this condition being overlooked. Few studies have focused on cognitive dysfunction after a pontine stroke. Here, we begin with describing our nine new case reports of in-depth neuropsychological findings from patients with pontine stroke. The dominant domain of cognitive dysfunction was commonly characterized by executive dysfunction, almost in line with previous studies. The severity was relatively mild. We give an overview of the available literature on cognitive decline following a pontine stroke. This is followed by discussions regarding the prognosis of the cognitive disabilities. Based on previous neuroimaging findings, we would like to get to the core of the neuropathology underlying the cognitive declines in the context of "diaschisis", a phenomenon of a broad range of brain dysfunctions remote from the local lesions. Specifically, our unique paper, with two modalities of neuroimaging techniques, may help us better understand the pathology. SPECT scans yield evidence of frontal and thalamic hyper-perfusion and cerebellar hypo-perfusion in patients with pontine stroke. Functional near-infrared spectroscopy, when focusing on the supplementary motor area (SMA) as one of the hyper-perfusion areas, exhibits that SMA responses may be subject to the severity of cognitive decline due to a pontine stroke and would also be related to the recovery. Finally, we posit that cognitive decline due to pontine stroke could be explained by the failure of hierarchical cognitive processing in the fronto-ponto-cerebellar-thalamic loop.

4.
Brain Dev ; 46(6): 224-229, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38556384

RESUMEN

BACKGROUND: It remains a matter of debate as to what extent early intervention may facilitate long-term functional outcomes of preterm infants in the neonatal intensive care unit (NICU). We aimed to examine the effect of increasing physical therapy (PT) staff dedicated to the NICU on temporal changes (initiation, duration) of PT interventions and functional outcomes (acquisition of full oral feeding and Hammersmith Neonatal Neurological Examination). METHODS: Extremely low birth weight infants, retrospectively collected from an academic medical center, were allocated to two subgroups, either a baseline period (N = 48) without NICU-dedicated PT staff (non-dedicated group) or a quality improvement period (N = 42) with additional dedicated staff (dedicated group). RESULTS: Compared to those in the non-dedicated group, NICU infants in the dedicated group started PT earlier and had increased PT treatment for additional 14 min per day when achieving full oral feeding. The infants in the dedicated group significantly achieved full oral feeding earlier than the non-dedicated group. As for Hammersmith Neonatal Neurological Examination, there were significant differences in two items (total and tone) between the groups. CONCLUSIONS: Additional NICU-dedicated PT staff facilitated earlier intervention and increased PT treatment in terms of daily duration. Moreover, the dedication shortened the completion of full oral feeding and improved neurological development, presumably resulting in better developmental outcome.


Asunto(s)
Recien Nacido con Peso al Nacer Extremadamente Bajo , Unidades de Cuidado Intensivo Neonatal , Humanos , Recién Nacido , Estudios Retrospectivos , Recien Nacido con Peso al Nacer Extremadamente Bajo/fisiología , Masculino , Femenino , Modalidades de Fisioterapia , Desarrollo Infantil/fisiología , Recien Nacido Prematuro/crecimiento & desarrollo , Recien Nacido Prematuro/fisiología
5.
Knee ; 42: 364-372, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37150024

RESUMEN

BACKGROUND: Biopsychosocial factors are involved in the occurrence of chronic post-surgical pain (CPSP) after total knee arthroplasty (TKA). The purpose of this study was to develop a clinical prediction rule (CPR) that considers biopsychosocial factors to predict which patients are more likely to develop CPSP after TKA. METHODS: CPSP after TKA was dichotomized into CPSP and non-CPSP groups using the Likert scale and Minimal clinically important difference, and binomial logistic regression analysis was performed. Cut-off values were then calculated using the extracted factors and dichotomized variables. The cut-off values and dichotomized variables were then used to derive a CPR that discriminates between groups with and without CPSP. RESULTS: Seventy-one TKA patients were included in the study. Binomial logistic regression analysis revealed that Central Sensitization Inventory (CSI) and Pittsburgh Sleep Quality Index (PSQI) were associated with CPSP. The cut-off values for CSI and PSQI were 26 and 7, respectively. The CPSP scale was created using the cut-off values of CSI and PSQI, with a score of 0 for being below the cut-off values of both CSI and PSQI, 1 for being above the cut-off values of either CSI or PSQI, and 2 for being above the cut-off values of both CSI and PSQI. Furthermore, the area under the curve (AUC) for CPR created by the presence of CPSP and using the CPSP scale was significant (AUC = 0.766; P = 0.001). CONCLUSION: The combination of the two tests, CSI and PSQI, suggested the possibility of predicting CPSP after TKA.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Dolor Crónico , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Estudios Prospectivos , Reglas de Decisión Clínica , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Dolor Postoperatorio/epidemiología , Dolor Crónico/diagnóstico , Dolor Crónico/etiología , Dolor Crónico/epidemiología
6.
Rev Sci Instrum ; 94(2): 025102, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36859009

RESUMEN

A new model-position-sensing method for the levitation of models with a low fineness ratio (ratio of the longitudinal length to the diameter) in a magnetic suspension and balance system (MSBS) is proposed. MSBS is an ideal model-support device for wind-tunnel testing, which enables the study of flow fields around blunt bodies without flow disturbances introduced by mechanical support devices, with the aerodynamic forces determined from the magnetic forces using a pre-calibrated relationship. The new method allows wind tunnel experiments without mechanical supports with a low fineness ratio model. This method adopts two line sensors placed parallel to the central axis of the model image and measures the position with a resolution finer than 0.06 mm or deg even for thin model geometries. In addition, measurement errors were reduced by correcting a second-order term in the depth direction of the camera. A low fineness ratio circular cylinder model was levitated following sensor calibration. The model was supported in conditions with and without freestream flow. This position measurement method was also applied to a reentry capsule model. The model was levitated while keeping its position and attitude stabilized near the origin.

7.
Sci Rep ; 13(1): 391, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36624172

RESUMEN

The rules governing the dimensions of the Javelin were substantially changed in 1986. It was considered that this new design guaranteed there was zero pitching moment at 0° angle of attack and that the pitching moment decreased (became negative) with increasing angle of attack. The objective of this study is to investigate if the pitching moment remains always negative (nose-down rotation). To measure accurate aerodynamic forces acting on a Javelin, the world's largest 1 m magnetic suspension and balance system was used. The magnetic suspension and balance system was able to measure aerodynamic forces without support interference in the wind tunnel. In addition, computational fluid dynamics were carried out to estimate the pitching moment coefficients. It was found that the pitching moment coefficient of a commercially available Javelin becomes positive (nose-up rotation) at lower angles of attack, less than 12°. The pitching moment becomes positive if the upstream side of the center of gravity receives more inflow than the downstream side. This situation can be attained by, for example, increasing the thickness of the upstream side when compared with that of the downstream side.


Asunto(s)
Hidrodinámica , Atletismo , Fenómenos Biomecánicos , Fenómenos Magnéticos , Rotación , Diseño de Equipo
8.
Case Rep Neurol Med ; 2022: 4828549, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36340934

RESUMEN

Background. In the acute phase of stroke, it is well known that the incidence and severity of unilateral spatial neglect (USN) are more significant in the right hemisphere injuries. Still, the detection of USN in left hemisphere injuries has been increasing in recent years. This trend is because behavioral assessments have prevented the exclusion of patients who are difficult to assess for USN or apathy using conventional paper-and-pencil tests (e.g., aphasia). Right USN and post-stroke apathy share many common lesions. Therefore, clinical symptoms may overlap, but little validation considers this. Case Study. A man (62 years old) determined to have the right USN and apathy was treated for six weeks in 3 terms. In the first term (weeks 1 to 2), the patient was treated for the right USN by conventional therapy. In the second term (3-4 weeks), treatment for right USN and apathy by goal-directed therapy based on affinity behavior was implemented. In the third term (5-6 weeks), goal-directed therapy based on affinity behavior was discontinued, and treatment was returned to conventional therapy only. In the second term (goal-directed therapy based on affinity behavior), the improvement in patients' apathy (clinical assessment for spontaneity) was more significant than the effect size in the third term (conventional therapy). There were no significant differences in USN (catherine bergego scale) and intrinsic motivation (pittsburgh rehabilitation participation scale). However, the effect size in the second term tended to be larger than in the third term (conventional therapy). Clinical Rehabilitation Impact. This report aims to demonstrate the limitations of current treatment for cases determined to have both right USN and apathy. Second, to assess the extent to which this new intervention can complement the limitations of current treatment.

9.
AIMS Neurosci ; 9(1): 1-11, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35434274

RESUMEN

Thalamic stroke may result in cognitive and linguistic problems, but the underlying mechanism remains unknown. Especially, it is still a matter of debate why thalamic aphasia occasionally occurs and then mostly recovers to some degree. We begin with a brief overview of the cognitive dysfunction and aphasia, and then review previous hypotheses of the underlying mechanism. We introduced a unique characteristic of relatively transient "word retrieval difficulty" of patients in acute phase of thalamic stroke. Word retrieval ability involves both executive function and speech production. Furthermore, SMA aphasia and thalamic aphasia may resemble in terms of the rapid recovery, thus suggesting a shared neural system. This ability is attributable to the supplementary motor area (SMA) and inferior frontal cortex (IFG) via the frontal aslant tract (FAT). To explore the possible mechanism, we applied unique hybrid neuroimaging techniques: single-photon emission computed tomography (SPECT) and functional near-infrared spectroscopy (f-NIRS). SPECT can visualize the brain distribution associated with word retrieval difficulty, cognitive disability or aphasia after thalamic stroke, and f-NIRS focuses on SMA and monitors long-term changes in hemodynamic SMA responses during phonemic verbal task. SPECT yielded common perfusion abnormalities not only in the fronto-parieto-cerebellar-thalamic loop, but also in bilateral brain regions such as SMA, IFG and language-relevant regions. f-NIRS demonstrated that thalamic stroke developed significant word retrieval decline, which was intimately linked to posterior SMA responses. Word retrieval difficulty was rapidly recovered with increased bilateral SMA responses at follow-up NIRS. Together, we propose that the cognitive domain affected by thalamic stroke may be related to the fronto-parieto-cerebellar-thalamic loop, while the linguistic region may be attributable to SMA, IFG and language-related brain areas. Especially, bilateral SMA may play a crucial role in the recovery of word retrieval, and right language-related region, including IFG, angular gyrus and supramarginal gyrus may determine recovery from thalamic aphasia.

10.
J Back Musculoskelet Rehabil ; 34(5): 829-835, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33935059

RESUMEN

BACKGROUND: Some patients with end-stage osteoarthritis of the knee remain unsatisfied after total knee arthroplasty (TKA). We postulated that to increase satisfaction, self-efficacy (SE) for physical activity should receive more attention in rehabilitative intervention, alongside the management of patient expectations, pain, and function. OBJECTIVE: We examined the relative impact of Physical Activity SE on Health-Related Quality of Life (HRQOL) alongside other factors such as pain and physical function which are well-addressed by current interventions. METHODS: One hundred and six first-TKA recipients (15 Male/91 Female, age 73.6 ± 7.2) were evaluated at 3 and 6 months post-operatively using the Medical Outcomes Study 36-Item Health Survey (SF-36v2) for HRQOL, knee extension strength measurement, Timed Up and Go test (TUG), One Leg Standing time test (OLS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for pain and function, and an instrument for measuring Physical Activity SE among the frail elderly in Japan. RESULTS: Significant improvement over pre-operative values was found at 3 and 6 months in TUG, OLS, WOMAC Pain and Function, and the 8 subscales of the SF-36v2. Factors found to significantly impact SF-36v2 subscale scores at 6 months post-operatively were found to be knee pain, knee function, and SE for physical activity. CONCLUSION: These results support our postulation that interventions to improve SE for physical activity could have comparable impact alongside interventions for knee pain and knee function, on the advancement of HRQOL among TKA recipients.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Anciano , Anciano de 80 o más Años , Ejercicio Físico , Femenino , Humanos , Masculino , Osteoartritis de la Rodilla/cirugía , Equilibrio Postural , Calidad de Vida , Autoeficacia , Estudios de Tiempo y Movimiento
11.
Vis Comput Ind Biomed Art ; 3(1): 20, 2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32851564

RESUMEN

Fluid dynamics simulation is often repeated under varying conditions. This leads to a generation of large amounts of results, which are difficult to compare. To compare results under different conditions, it is effective to overlap the streamlines generated from each condition in a single three-dimensional space. Streamline is a curved line, which represents a wind flow. This paper presents a technique to automatically select and visualize important streamlines that are suitable for the comparison of the simulation results. Additionally, we present an implementation to observe the flow fields in virtual reality spaces.

12.
NeuroRehabilitation ; 46(4): 569-575, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32508342

RESUMEN

BACKGROUND: It is very difficult for patients with severe upper extremity (UE) paresis after stroke to achieve full recovery because of the lack of a definitive approach for improving severe UE paresis immediately after onset. OBJECTIVE: to investigate the effects of repetitive peripheral magnetic stimulation (rPMS) on severe UE paresis during early acute phase of stroke. METHODS: Nineteen participants with severe UE disability met the criteria. 10 subjects received 15-20 minutes of rPMS prior to standard care per session, while 9 age- and severity-matched subjects received two times 20 minutes of standard care. Outcome measures included UE motor section of the Fugl-Meyer Motor Assessment Scale (FMA-UE), Wolf motor function test (WMFT), and box and block test (BBT). RESULTS: The rPMS group received treatment (average sessions: 7.8) after a median 9.2 days from stroke (16.5 sessions after 5 days for control). To adjust the different treatment durations, we defined "progress rate" as the gains of UE function scores divided by treatment duration. The progress rate was significantly different in FMA-UE and WMFT, but not in BBT. CONCLUSIONS: The present study suggested beneficial effects of rPMS on severe UE paresis during early acute phase of stroke.


Asunto(s)
Magnetoterapia/métodos , Paresia/terapia , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/fisiopatología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Paresia/etiología , Accidente Cerebrovascular/complicaciones , Extremidad Superior/fisiopatología
13.
NeuroRehabilitation ; 46(3): 417-422, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32310196

RESUMEN

BACKGROUND: Few patients with severe upper extremity (UE) paresis after stroke achieved full recovery, because of the lack of a definitive approach to improve severe UE paresis immediately after onset. OBJECTIVE: to investigate the effects of coupled EMG-triggered and cyclic neuromuscular electrical stimulation (NMES) on UE paresis during early acute phase of stroke. METHODS: Seventeen participants with severe UE disability met the criteria. 8 subjects received 20 minutes of NMES prior to standard care per session, while 9 age- and severity-matched subjects received two times 20 minutes of standard care. Outcome measures included UE motor section of the Fugl-Meyer Motor Assessment Scale (FMA-UE), Wolf motor function test (WMFT), and box and block test (BBT). RESULTS: The NMES group received treatment (average session: 10.87) after a median 7 days from stroke (16.5 sessions after 5 days for control). To adjust the different treatment durations, we defined "progress rate" as the gains of UE function scores divided by treatment duration. The progress rate was significantly different in FMA-UE, but not in WMFT and BBT. CONCLUSIONS: The present study suggested beneficial effects of coupled NMES on UE paresis during early acute phase of stroke.


Asunto(s)
Terapia por Estimulación Eléctrica , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/fisiopatología , Extremidad Superior/fisiopatología , Humanos
14.
Brain Sci ; 10(4)2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32331319

RESUMEN

Damage to the thalamus may affect cognition and language, but the underlying mechanism remains unknown. In particular, it remains a riddle why thalamic aphasia occasionally occurs and then mostly recovers to some degree. To explore the mechanism of the affected cognition and language, we used two neuroimaging techniques-single-photon emission computed tomography (SPECT), suitable for viewing the affected brain distribution after acute thalamic stroke, and functional near-infrared spectroscopy (f-NIRS), focusing on hemodynamic responses of the supplementary motor area (SMA) responsible for speech production in conjunction with the frontal aslant tract (FAT) pathway. SPECT yielded common perfusion abnormalities not only in the fronto-parieto-cerebellar loop, but also in the SMA, IFG and surrounding language-relevant regions. In NIRS sessions during a phonemic verbal fluency task, we found significant word retrieval decline in acute thalamic patients relative to age-matched healthy volunteers. Further, NIRS showed strong correlation between word retrieval and posterior SMA responses. In addition, follow-up NIRS exhibited increased bilateral SMA responses linked to improving word retrieval ability. The findings suggest that cognitive dysfunction may be related to the fronto-parieto-cerebellar loop, while language dysfunction is attributed to the SMA, IFG and language-related brain areas. SMA may contribute to the recovery of word retrieval difficulty and aphasia after thalamic stroke.

15.
J Phys Ther Sci ; 31(11): 889-894, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31871372

RESUMEN

[Purpose] The purpose of this study was to identify the factors influencing change in life-space mobility after total knee arthroplasty (TKA) in patients with severe knee osteoarthritis (knee OA). [Participants and Methods] Overall, 58 primary unilateral TKA recipients (9 males and 49 females; age ± SD 74.6 ± 6.5 years) were enrolled. We evaluated Life-Space Assessment (LSA) scores, knee extensor strength, Timed Up and Go test (TUG), one-leg standing time (OLS), Western Ontario and McMaster Universities osteoarthritis Index, and physical activity self-efficacy (SE) before surgery and at 3 months post-operation. [Results] Life space mobility significantly expanded 3 months after surgery compared with preoperative baseline. Preoperatively, walking SE and knee extensor muscle strength on the operative side were found to have strong correlation with LSA scores, while stairs SE and knee extensor muscle strength of the operative side were correlated at 3 months post-operation. [Conclusion] These findings suggest that to expand the life-space mobility of TKA recipients, it is important to enhance self-efficacy for general physical activity in addition to strengthening the quadriceps muscles.

16.
NeuroRehabilitation ; 44(2): 251-261, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31006695

RESUMEN

BACKGROUNDThere is a tendency to pay little attention to cognitive dysfunction after a subcortical stroke, resulting in this condition being overlooked. Damage to the brainstem may affect cognition, probably originating from the fronto-cerebellar circuit, but details remain obscure.OBJECTIVETo investigate the effect of damage to pons on frontal function via the fronto-cerebellar circuit.METHODSWe measured frontal dynamic responses in patients with acute pontine ischemia during phonemic verbal fluency task using near-infrared spectroscopy (NIRS). Furthermore, to determine whether the fronto-cerebellar circuit is affected by pontine ischemia, 99 mTc-ECD single photon emission computed tomography (SPECT) was performed.RESULTSTwenty-five patients with pontine isolated infarction met the criteria. Especially, 80 percent of the pontine lesioned patients affected cognition. The patients exhibited hyper-frontal activity according to the neuropsychological tests. Follow-up NIRS showed increased frontal activity as being linked to improved cognition. This may indicate the involvement of frontal activity in cognitive recovery. The SPECT showed consistently hyper-frontal perfusion as well as hypo-cerebellar perfusion.CONCLUSIONSThis suggested that hyper-frontal activity might contribute to compensation for cognitive dysfunction after pontine ischemia and that recovery from the cognitive deficits is attributable to frontal activity.


Asunto(s)
Isquemia Encefálica/fisiopatología , Disfunción Cognitiva/diagnóstico por imagen , Lóbulo Frontal/diagnóstico por imagen , Puente/irrigación sanguínea , Adulto , Anciano , Isquemia Encefálica/complicaciones , Cerebelo/diagnóstico por imagen , Cerebelo/fisiopatología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/fisiopatología , Femenino , Lóbulo Frontal/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada de Emisión de Fotón Único
17.
Neural Plast ; 2016: 6168245, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27413555

RESUMEN

To understand cortical mechanisms related to truncal posture control during human locomotion, we investigated hemodynamic responses in the supplementary motor area (SMA) with quadrupedal and bipedal gaits using functional near-infrared spectroscopy in 10 healthy adults. The subjects performed three locomotor tasks where the degree of postural instability varied biomechanically, namely, hand-knee quadrupedal crawling (HKQuad task), upright quadrupedalism using bilateral Lofstrand crutches (UpQuad task), and typical upright bipedalism (UpBi task), on a treadmill. We measured the concentration of oxygenated hemoglobin (oxy-Hb) during the tasks. The oxy-Hb significantly decreased in the SMA during the HKQuad task, whereas it increased during the UpQuad task. No significant responses were observed during the UpBi task. Based on the degree of oxy-Hb responses, we ranked these locomotor tasks as UpQuad > UpBi > HKQuad. The order of the different tasks did not correspond with postural instability of the tasks. However, qualitative inspection of oxy-Hb time courses showed that oxy-Hb waveform patterns differed between upright posture tasks (peak-plateau-trough pattern for the UpQuad and UpBi tasks) and horizontal posture task (downhill pattern for the HKQuad task). Thus, the SMA may contribute to the control of truncal posture accompanying locomotor movements in humans.


Asunto(s)
Hemodinámica/fisiología , Locomoción/fisiología , Corteza Motora/fisiología , Postura/fisiología , Desempeño Psicomotor/fisiología , Adulto , Prueba de Esfuerzo/métodos , Femenino , Hemoglobinas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Espectroscopía Infrarroja Corta/métodos , Adulto Joven
18.
EJNMMI Res ; 4: 24, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25045603

RESUMEN

BACKGROUND: Abnormal behaviors of young patients after taking the anti-influenza agent oseltamivir (Tamiflu®, F. Hoffmann-La Roche, Ltd., Basel, Switzerland) have been suspected as neuropsychiatric adverse events (NPAEs). Immune response to viral infection is suspected to cause elevation of drug concentration in the brain of adolescents. In the present study, the effect of innate immune activation on the brain uptake of [(11)C]oseltamivir was quantitatively evaluated in juvenile monkeys. METHODS: Three 2-year-old monkeys underwent positron emission tomography (PET) scans at baseline and immune-activated conditions. Both scans were conducted under pre-dosing of clinically relevant oseltamivir. The immune activation condition was induced by the intravenous administration of polyinosine-polycytidylic acid (poly I:C). Dynamic [(11)C]oseltamivir PET scan and serial arterial blood sampling were performed to obtain [(11)C]oseltamivir kinetics. Brain uptake of [(11)C]oseltamivr was evaluated by its normalized brain concentration, brain-to-plasma concentration ratio, and plasma-to-brain transfer rate. Plasma pro-inflammatory cytokine levels were also measured. RESULTS: Plasma interleukin-6 was elevated after intravenous administration of poly I:C in all monkeys. Brain radioactivity was uniform both at baseline and under poly I:C treatment. The mean brain concentrations of [(11)C]oseltamivir were 0.0033 and 0.0035% ID/cm(3) × kg, the mean brain-to-plasma concentration ratios were 0.58 and 0.65, and the plasma-to-brain transfer rates were 0.0047 and 0.0051 mL/min/cm(3) for baseline and poly I:C treatment, respectively. Although these parameters were slightly changed by immune activation, the change was not notable. CONCLUSIONS: The brain uptake of [(11)C]oseltamivir was unchanged by poly I:C treatment in juvenile monkeys. This study demonstrated that the innate immune response similar to the immune activation of influenza would not notably change the brain concentration of oseltamivir in juvenile monkeys.

19.
Brain Inj ; 27(13-14): 1685-91, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24266797

RESUMEN

PRIMARY OBJECTIVE: To study the mechanism of somatosensory-vestibular interactions, this study examined the effects of somatosensory inputs on body sway induced by galvanic vestibular stimulation (GVS) in healthy participants and persons with brain injury in the posterior insula, a region constituting a part of the parietoinsular vestibular cortex. RESEARCH DESIGN: This study adopted an experimental, controlled, repeated measures design. METHODS AND PROCEDURES: Participants were 11 healthy individuals, two persons with unilateral posterior insular injury and two age-matched controls. Bipolar GVS was applied to the mastoid processes while participants were sitting with their eyes closed, either lightly touching a stable surface with their index finger or not touching the surface with their index finger. MAIN OUTCOMES AND RESULTS: In healthy participants, tilting was greater with right hemispheric stimulation than with left hemispheric stimulation. Moreover, with right hemispheric stimulation, tilting was greater with a right finger touch than with no touch. The person with right-brain injury showed tilting induced by GVS; however, finger touch had no modulatory effect. In contrast, finger touch enhanced tilting in the person with left-brain injury. CONCLUSIONS: These preliminary results are discussed in light of a hypothesis of right hemispheric dominance of somatosensory-vestibular interactions in the posterior insula.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Corteza Somatosensorial/fisiopatología , Percepción del Tacto , Tacto , Adulto , Análisis de Varianza , Estudios de Casos y Controles , Corteza Cerebral , Estimulación Eléctrica , Femenino , Lateralidad Funcional , Humanos , Masculino , Persona de Mediana Edad , Vestíbulo del Laberinto
20.
Clin Neurophysiol ; 124(10): 2008-15, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23706813

RESUMEN

OBJECTIVE: The relation was investigated between hemiparetic arm function improvement and brain cortical perfusion (BCP) change during voluntary muscle contraction (VOL), EMG-controlled FES (EMG-FES) and simple electrical muscle stimulation (ES) before and after EMG-FES therapy in chronic stroke patients. METHODS: Sixteen chronic stroke patients with moderate residual hemiparesis underwent 5 months of task-orientated EMG-FES therapy of the paretic arm once or twice a week. Before and after treatment, arm function was clinically evaluated and BCP during VOL, ES and EMG-FES were assessed using multi-channel near-infrared spectroscopy. RESULTS: BCP in the ipsilesional sensory-motor cortex (SMC) was greater during EMG-FES than during VOL or ES; therefore, EMG-FES caused a shift in the dominant BCP from the contralesional to ipsilesional SMC. After EMG-FES therapy, arm function improved in most patients, with some individual variability, and there was significant improvement in Fugl-Meyer (FM) score and maximal grip strength (GS). Clinical improvement was accompanied by an increase in ipsilesional SMC activation during VOL and EMG-FES condition. CONCLUSION: The EMG-FES may have more influence on ipsilesional BCP than VOL or ES alone. SIGNIFICANCE: The sensory motor integration during EMG-FES therapy might facilitate BCP of the ipsilesional SMC and result in functional improvement of hemiparetic upper extremity.


Asunto(s)
Brazo/fisiopatología , Terapia por Estimulación Eléctrica , Corteza Motora/fisiopatología , Paresia/fisiopatología , Paresia/rehabilitación , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/fisiopatología , Adolescente , Adulto , Anciano , Mapeo Encefálico , Circulación Cerebrovascular , Terapia por Estimulación Eléctrica/métodos , Electromiografía/métodos , Femenino , Lateralidad Funcional , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Oxihemoglobinas/metabolismo , Paresia/complicaciones , Espectroscopía Infrarroja Corta , Accidente Cerebrovascular/complicaciones , Resultado del Tratamiento , Adulto Joven
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