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1.
Artículo en Inglés | MEDLINE | ID: mdl-37987197

RESUMEN

CONTEXT: Media messaging matters for public opinion and policy, and analyzing patterns of campaign strategy can provide important windows into policy priorities. METHODS: We used content analysis supplemented with keyword-based text analysis to assess the volume, proportion and distribution of attention to race-related issues in comparison to gender-related issues during the general election period of the 2022 midterm campaigns for federal office. FINDINGS: Race-related mentions were overwhelmingly focused on crime and law and order with very little attention to racism, racial injustice, and the structural barriers that lead to widespread inequities. In stark contrast to mentions of gender, racial appeals were less identity focused and were competitively contested between the parties in their messaging, but much more likely to be led by Republicans. CONCLUSIONS: Our results suggest that discussion of race and gender were highly polarized with consequences for public understanding of and belief in disparities and policies important to population health.

2.
J Neurophysiol ; 115(6): 3045-51, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27009158

RESUMEN

The information coming from the vestibular otolith organs is important for the brain when reflexively making appropriate visual and spinal corrections to maintain balance. Symptoms related to failed balance control and navigation are commonly observed in astronauts returning from space. To investigate the effect of microgravity exposure on the otoliths, we studied the otolith-mediated responses elicited by centrifugation in a group of 25 astronauts before and after 6 mo of spaceflight. Ocular counterrolling (OCR) is an otolith-driven reflex that is sensitive to head tilt with regard to gravity and tilts of the gravito-inertial acceleration vector during centrifugation. When comparing pre- and postflight OCR, we found a statistically significant decrease of the OCR response upon return. Nine days after return, the OCR was back at preflight level, indicating a full recovery. Our large study sample allows for more general physiological conclusions about the effect of prolonged microgravity on the otolith system. A deconditioned otolith system is thought to be the cause of several of the negative effects seen in returning astronauts, such as spatial disorientation and orthostatic intolerance. This knowledge should be taken into account for future long-term space missions.


Asunto(s)
Astronautas , Movimientos Oculares/fisiología , Membrana Otolítica/fisiología , Reflejo Vestibuloocular/fisiología , Vuelo Espacial , Ingravidez , Adulto , Distribución de Chi-Cuadrado , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rotación , Factores de Tiempo
3.
J Neuroeng Rehabil ; 10: 19, 2013 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-23405951

RESUMEN

BACKGROUND: We have previously published a technique for objective assessment of freezing of gait (FOG) in Parkinson's disease (PD) from a single shank-mounted accelerometer. Here we extend this approach to evaluate the optimal configuration of sensor placement and signal processing parameters using seven sensors attached to the lumbar back, thighs, shanks and feet. METHODS: Multi-segmental acceleration data was obtained from 25 PD patients performing 134 timed up and go tasks, and clinical assessment of FOG was performed by two experienced raters from video. Four metrics were used to compare objective and clinical measures; the intraclass correlation coefficient (ICC) for number of FOG episodes and the percent time frozen per trial; and the sensitivity and specificity of FOG detection. RESULTS: The seven-sensor configuration was the most robust, scoring highly on all measures of performance (ICC number of FOG 0.75; ICC percent time frozen 0.80; sensitivity 84.3%; specificity 78.4%). A simpler single-shank sensor approach provided similar ICC values and exhibited a high sensitivity to FOG events, but specificity was lower at 66.7%. Recordings from the lumbar sensor offered only moderate agreement with the clinical raters in terms of absolute number and duration of FOG events (likely due to musculoskeletal attenuation of lower-limb 'trembling' during FOG), but demonstrated a high sensitivity (86.2%) and specificity (82.4%) when considered as a binary test for the presence/absence of FOG within a single trial. CONCLUSIONS: The seven-sensor approach was the most accurate method for quantifying FOG, and is best suited to demanding research applications. A single shank sensor provided measures comparable to the seven-sensor approach but is relatively straightforward in execution, facilitating clinical use. A single lumbar sensor may provide a simple means of objective FOG detection given the ubiquitous nature of accelerometers in mobile telephones and other belt-worn devices.


Asunto(s)
Trastornos Neurológicos de la Marcha/etiología , Trastornos Neurológicos de la Marcha/fisiopatología , Extremidad Inferior/fisiología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/fisiopatología , Fenómenos Biomecánicos , Estudios de Cohortes , Interpretación Estadística de Datos , Electrodos , Femenino , Pie/fisiología , Humanos , Pierna/fisiología , Locomoción/fisiología , Región Lumbosacra/fisiología , Masculino , Fenómenos Fisiológicos Musculoesqueléticos , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Programas Informáticos , Muslo/fisiología
4.
Exp Brain Res ; 216(2): 275-85, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22076407

RESUMEN

Although imaging studies suggest activation of cortical areas by vestibular input, there is little evidence of an adverse effect of non-veridical vestibular input on cognitive function. To test the hypothesis that degraded vestibular afferent input adversely affects cognition, we compared performance on a cognitive test battery in a group undergoing suprathreshold bilateral bipolar Galvanic vestibular stimulation (GVS) with a control group receiving no GVS or subthreshold stimulation. The battery consisted of six cognitive tests as follows: reaction time, dual tasking, Stroop, mental rotation, perspective-taking and matching-to-sample, as well as a simple visuomotor (manual tracking) task. Subjects performed the test battery before, during and after suprathreshold GVS exposure or subthreshold stimulation. Suprathreshold GVS significantly increased error rate for the match-to-sample and perspective-taking tasks relative to the subthreshold group, demonstrating a negative effect of non-veridical vestibular input in these specific cognitive tasks. Reaction time, dual tasking, mental rotation and manual tracking were unaffected by GVS exposure. The adverse effect of suprathreshold GVS on perspective taking but not mental rotation is consistent with imaging studies, which have demonstrated that egocentric mental transformations (perspective taking) occur primarily in cortical areas that receive vestibular input (the parietal-temporal junction and superior parietal lobule), whereas object-based transformations (mental rotation) occur in the frontoparietal region. The increased error rate during the match-to-sample task is likely due to interference with hippocampal processing related to spatial memory, as suggested by imaging studies on vestibular patients.


Asunto(s)
Cognición/fisiología , Estimulación Eléctrica , Vestíbulo del Laberinto/fisiología , Adulto , Vías Aferentes/fisiología , Atención/fisiología , Femenino , Humanos , Imaginación/fisiología , Masculino , Memoria/fisiología , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Rotación , Umbral Sensorial/fisiología , Vuelo Espacial , Test de Stroop
5.
PLoS One ; 17(10): e0275595, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36201500

RESUMEN

Televised public service announcements were one of the ways that the U.S. federal government distributed health information about the COVID-19 pandemic to Americans in 2020. However, little is known about the reach of these campaigns or the populations who might have been exposed to the information these ads conveyed. We conducted a descriptive analysis of federally-affiliated public service announcement airings to assess where they were aired and the market-level social and demographic characteristics associated with the airings. We found no correspondence between airings and COVID-19 incidence rates from March to December 2020, but we found a positive association between airings and the Democratic vote share of the market, adjusting for other market demographic characteristics. Our results suggest that PSAs may have contributed to divergent exposure to health information among the U.S. public during the first year of the COVID-19 pandemic.


Asunto(s)
COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Humanos , Pandemias , Televisión , Estados Unidos/epidemiología
6.
Biomed Eng Online ; 10: 82, 2011 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-21936884

RESUMEN

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder resulting in motor disturbances that can impact normal gait. Although PD initially responds well to pharmacological treatment, as the disease progresses efficacy often fluctuates over the course of the day, and clinical management would benefit from long-term objective measures of gait. We have previously described a small device worn on the shank that uses acceleration and angular velocity sensors to calculate stride length and identify freezing of gait in PD patients. In this study we extend validation of the gait monitor to 24-h using simultaneous video observation of PD patients. METHODS: A sleep laboratory was adapted to perform 24-hr video monitoring of patients while wearing the device. Continuous video monitoring of a sleep lab, hallway, kitchen and conference room was performed using a 4-camera security system and recorded to hard disk. Subjects (3) wore the gait monitor on the left shank (just above the ankle) for a 24-h period beginning around 5 pm in the evening. Accuracy of stride length measures were assessed at the beginning and end of the 24-h epoch. Two independent observers rated the video logs to identify when subjects were walking or lying down. RESULTS: The mean error in stride length at the start of recording was 0.05 m (SD 0) and at the conclusion of the 24 h epoch was 0.06 m (SD 0.026). There was full agreement between observer coding of the video logs and the output from the gait monitor software; that is, for every video observation of the subject walking there was a corresponding pulse in the monitor data that indicated gait. CONCLUSIONS: The accuracy of ambulatory stride length measurement was maintained over the 24-h period, and there was 100% agreement between the autonomous detection of locomotion by the gait monitor and video observation.


Asunto(s)
Marcha , Monitoreo Ambulatorio/métodos , Enfermedad de Parkinson/fisiopatología , Aceleración , Anciano , Femenino , Humanos , Levodopa/uso terapéutico , Masculino , Enfermedad de Parkinson/tratamiento farmacológico
7.
Aviat Space Environ Med ; 82(5): 535-42, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21614868

RESUMEN

BACKGROUND: Exposure to microgravity adversely affects performance of astronaut pilots; a review of the first 100 Shuttle missions found that touchdown speed was above specified limits in 20% of landings, in contrast to near ideal performance in preflight high-fidelity Shuttle simulations. Ground-based simulators emphasize spacecraft handling abilities, but do not recreate the effects of extended weightlessness on sensorimotor function. The aim of this study was to validate an analogue of the sensorimotor effects of microgravity using pseudorandom bilateral bipolar galvanic vestibular stimulation (GVS) during Shuttle landing simulations. METHODS: Pilot performance was assessed during simulated Shuttle landings in the Vertical Motion Simulator at NASA Ames Research Center, Moffett Field, CA (used for astronaut pilot training). Subjects (N = 11) flew eight pairs of identical landing profiles (final approach and touchdown), with and without GVS, presented in a pseudorandom order. RESULTS: Touchdown speed was on target (204 kn) without GVS [203.8 kn], but increased significantly during GVS exposure 1208.5 kn] and was at the upper limit (209 kn) of the target range. The adverse effects of GVS on pilot performance were obvious. Unsuccessful (crash) landings increased from 2.3% (2/88) without GVS to 9% (7/88) with GVS. Hard landings, with touchdown speed in the 'red' (unacceptable) range (> 214 kn), almost doubled from 14 (15.9%) without GVS to 27 (30.7%) with GVS. CONCLUSION: GVS was an effective analogue of decrements in postflight Shuttle pilot performance.


Asunto(s)
Percepción Espacial , Pruebas de Función Vestibular , Simulación de Ingravidez , Medicina Aeroespacial , Humanos , Masculino , Equilibrio Postural , Vuelo Espacial
8.
Aviat Space Environ Med ; 82(8): 770-4, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21853854

RESUMEN

BACKGROUND: We have developed an analogue of postflight sensorimotor dysfunction in astronauts using pseudorandom galvanic vestibular stimulation (GVS). To date there has been no study of the effects of extended GVS on human subjects and our aim was to determine optimal exposure for astronaut training based on tolerance to intermittent and continuous galvanic stimulation. METHODS: There were 60 subjects who were exposed to a total of 10.5 min of intermittent GVS at a peak current of 3.5 mA or 5 mA. A subset of 24 subjects who tolerated the intermittent stimulus were subsequently exposed to 20-min continuous stimulation at 3.5 mA or 5 mA. RESULTS: During intermittent GVS the large majority of subjects (78.3%) reported no or at most mild motion sickness symptoms, 13.3% reported moderate symptoms, and 8.3% experienced severe nausea and requested termination of the stimulus. During 20-min continuous exposure, 83.3% of subjects reported no or at most mild motion sickness symptoms and 16.7% (all in the 5-mA group) experienced severe nausea. CONCLUSION: Based on these results, we propose two basic modes of GVS application to minimize the incidence of motion sickness: intermittent high (5 mA) amplitude, suited to simulation of intensive operator tasks requiring a high-fidelity analogue of postflight sensorimotor dysfunction such as landing or docking maneuvers; and continuous low (3.5 mA) amplitude stimulation, for longer simulation scenarios such as extra vehicular activity. Our results suggest that neither mode of stimulation would induce motion sickness in the large majority of subjects for up to 20 min exposure.


Asunto(s)
Astronautas , Estimulación Eléctrica/métodos , Mareo por Movimiento/fisiopatología , Vuelo Espacial , Pruebas de Función Vestibular/métodos , Vestíbulo del Laberinto/fisiología , Astronautas/educación , Femenino , Humanos , Masculino , Enseñanza/métodos , Vestíbulo del Laberinto/fisiopatología
9.
Sci Rep ; 11(1): 15733, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34344970

RESUMEN

The use of autonomous recordings of animal sounds to detect species is a popular conservation tool, constantly improving in fidelity as audio hardware and software evolves. Current classification algorithms utilise sound features extracted from the recording rather than the sound itself, with varying degrees of success. Neural networks that learn directly from the raw sound waveforms have been implemented in human speech recognition but the requirements of detailed labelled data have limited their use in bioacoustics. Here we test SincNet, an efficient neural network architecture that learns from the raw waveform using sinc-based filters. Results using an off-the-shelf implementation of SincNet on a publicly available bird sound dataset (NIPS4Bplus) show that the neural network rapidly converged reaching accuracies of over 65% with limited data. Their performance is comparable with traditional methods after hyperparameter tuning but they are more efficient. Learning directly from the raw waveform allows the algorithm to select automatically those elements of the sound that are best suited for the task, bypassing the onerous task of selecting feature extraction techniques and reducing possible biases. We use publicly released code and datasets to encourage others to replicate our results and to apply SincNet to their own datasets; and we review possible enhancements in the hope that algorithms that learn from the raw waveform will become useful bioacoustic tools.


Asunto(s)
Acústica , Aves/fisiología , Aprendizaje Profundo , Aprendizaje Automático , Sonido , Vocalización Animal , Algoritmos , Animales , Redes Neurales de la Computación
10.
Exp Brain Res ; 204(4): 617-22, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20535455

RESUMEN

We studied spatial orientation before and after 21 days of 6 degrees head-down bed rest in 15 subjects. During bed rest, 8 subjects were treated daily with 1 h Gz centrifugation (artificial gravity) (2.5 g at the feet; 1.0 g at the heart), with 7 subjects serving as controls. Ocular counter-rolling and subjective visual vertical were assessed during 90 degrees whole body roll tilt to the left and right. Ocular counter-rolling was unaffected by bed rest and bed rest + artificial gravity. Performance on the subjective visual vertical task was unchanged in the control group, but exhibited a significant increase in error for 48 h after bed rest in the treatment (artificial gravity) group. Intermittent application of linear acceleration along the long body axis may have increased the weighting of the idiotropic vector, resulting in an increased bias of the subjective visual vertical toward the long body axis during 90 degrees roll tilt.


Asunto(s)
Gravedad Alterada , Inclinación de Cabeza , Orientación/fisiología , Percepción Espacial/fisiología , Adaptación Fisiológica/fisiología , Adulto , Reposo en Cama , Centrifugación , Sensación de Gravedad/fisiología , Movimientos de la Cabeza/fisiología , Humanos , Masculino , Postura/fisiología , Vestíbulo del Laberinto/fisiología
11.
Exp Dermatol ; 18(4): 362-9, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18803656

RESUMEN

The purpose of this study was to determine the effect of transplanted human mesenchymal stem cells (hMSCs) on wound healing. In this model, full-thickness cutaneous wounds were created by incision in the skin of adult New Zealand white rabbits and treated by transplanted hMSCs into the wounds. Wound healing was evaluated by histological analysis and tensiometry over time. A total of 15 New Zealand white rabbits with 10 wounds per animal were examined in this study. Animals were treated with hMSCs and euthanised at 3, 7, 14, 21 and 80 days after manipulation. The hMSCs were labelled with a fluorescent dye (CM-DiI), suspended in phosphate-buffered saline and used to treat full-thickness incisional wounds in rabbit skin. Tensiometry and histology were used to characterise the wound-healing rate of the incisional wounds. These results showed that transplanted hMSCs significantly inhibited scar formation and increased the tensile strength of the wounds. Importantly, MSCs from genetically unrelated donors did not appear to induce an immunologic response. In conclusion, human mesenchymal stem cell therapy is a viable approach to significantly affect the course of normal cutaneous wound healing and significantly increase the tensile strength.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas/métodos , Piel/lesiones , Cicatrización de Heridas/fisiología , Animales , Cicatriz/prevención & control , Humanos , Modelos Animales , Conejos , Piel/patología , Resistencia a la Tracción/fisiología , Factores de Tiempo , Trasplante Heterólogo
12.
Sci Rep ; 9(1): 2677, 2019 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-30804413

RESUMEN

Performance of astronaut pilots during space shuttle landing was degraded after a few weeks of microgravity exposure, and longer-term exposure has the potential to impact operator proficiency during critical landing and post-landing operations for exploration-class missions. Full-motion simulations of operationally-relevant tasks were utilized to assess the impact of long-duration spaceflight on operator proficiency in a group of 8 astronauts assigned to the International Space Station, as well as a battery of cognitive/sensorimotor tests to determine the underlying cause of any post-flight performance decrements. A ground control group (N = 12) and a sleep restriction cohort (N = 9) were also tested to control for non-spaceflight factors such as lack of practice between pre- and post-flight testing and fatigue. On the day of return after 6 months aboard the space station, astronauts exhibited significant deficits in manual dexterity, dual-tasking and motion perception, and a striking degradation in the ability to operate a vehicle. These deficits were not primarily due to fatigue; performance on the same tasks was unaffected after a 30-h period of sleep restriction. Astronauts experienced a general post-flight malaise in motor function and motion perception, and a lack of cognitive reserve apparent only when faced with dual tasks, which had recovered to baseline by four days after landing.


Asunto(s)
Astronautas/estadística & datos numéricos , Vuelo Espacial , Nave Espacial , Ingravidez , Adulto , Astronautas/psicología , Cognición/fisiología , Humanos , Masculino , Persona de Mediana Edad , Percepción de Movimiento/fisiología , Pruebas Psicológicas/estadística & datos numéricos , Desempeño Psicomotor/fisiología , Sueño/fisiología , Factores de Tiempo
13.
J Neurosci Methods ; 167(2): 340-8, 2008 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-17928063

RESUMEN

Freezing of gait (FOG) is common in advanced Parkinson's disease (PD), is resistant to treatment and negatively impacts quality of life. In this study an ambulatory FOG monitor was validated in 11 PD patients. The vertical linear acceleration of the left shank was acquired using an ankle-mounted sensor array that transmitted data wirelessly to a pocket PC at a rate of 100 Hz. Power analysis showed high-frequency components of leg movement during FOG in the 3-8 Hz band that were not apparent during volitional standing, and power in this 'freeze' band was higher (p=0.00003) during FOG preceded by walking (turning or obstacles) than FOG preceded by rest (gait initiation). A freeze index (FI) was defined as the power in the 'freeze' band divided by the power in the 'locomotor' band (0.5-3 Hz) and a threshold chosen such that FI values above this limit were designated as FOG. A global threshold detected 78% of FOG events and 20% of stand events were incorrectly labeled as FOG. Individual calibration of the freeze threshold improved accuracy and sensitivity of the device to 89% for detection of FOG with 10% false positives. Ambulatory monitoring may significantly improve clinical management of FOG.


Asunto(s)
Trastornos Neurológicos de la Marcha/inducido químicamente , Trastornos Neurológicos de la Marcha/fisiopatología , Levodopa/efectos adversos , Monitoreo Ambulatorio/instrumentación , Monitoreo Ambulatorio/métodos , Adulto , Anciano , Femenino , Marcha/efectos de los fármacos , Marcha/fisiología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/fisiopatología , Análisis Espectral
14.
Exp Brain Res ; 184(4): 469-78, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17828529

RESUMEN

The aim of this study was to quantify the dynamic response of locomotion to the first oral levodopa administration of the day in patients with fluctuating Parkinson's disease (PD). Stride length, walking speed, cadence and gait variability were measured with an ambulatory gait monitor in 13 PD patients (8 males) with a clinical history of motor fluctuations. The Unified Parkinson's Disease Rating Scale (UPDRS) gait score (part 29) was also determined by a movement disorders specialist from video recordings. Subjects arrived in the morning in an 'off' state (no PD medication) and walked for a maximum length of 100 m. They then took their usual morning dose of oral levodopa and repeated the walking task at 13 min intervals (on average) over a 90 min period. Changes in stride length over time were fit with a Hill (Emax) function. Latency (time until stride length increased 15% of the difference between baseline and maximum response) and the Hill coefficient (shape of the 'off-on' transition) were determined from the fitted curve. Latency varied from 4.7 to 53.3 min post-administration [23.31 min (SD 14.9)], and was inversely correlated with age at onset of PD (R = -0.83; P = 0.0004). The Hill coefficient (H) ranged from a smooth hyperbolic curve (0.9) to an abrupt 'off-on' transition (16.9), with a mean of 8.1 (SD 4.9). H correlated with disease duration (R = 0.67; P = 0.01) and latency (R = 0.67; P = 0.01), and increased with Hoehn & Yahr stage in the 'off' state (P = 0.02) from 5.7 (SD 3.5) (H&Y III) to 11.9 (SD 4.7) (H&Y IV). Walking speed correlated with changes in mean stride length, whereas cadence and gait variability did not. UPDRS gait score also reflected improving gait in the majority of subjects (8), providing clinical confirmation of the objective measures of the locomotor response to levodopa. Increasing abruptness (H) of the 'off-on' transition with disease duration is consistent with results from finger-tapping studies, and may reflect reduced buffering capacity of pre-synaptic nigrostriatal dopaminergic neurons. Ambulatory monitoring of gait objectively measures the dynamic locomotor response to levodopa, and this information could be used to improve daily management of motor fluctuations.


Asunto(s)
Antiparkinsonianos/administración & dosificación , Levodopa/administración & dosificación , Actividad Motora/efectos de los fármacos , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/fisiopatología , Administración Oral , Edad de Inicio , Anciano , Femenino , Marcha/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/efectos de los fármacos , Índice de Severidad de la Enfermedad
15.
J Mol Med (Berl) ; 85(5): 481-96, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17219096

RESUMEN

Fibromodulin, a member of the small leucine-rich proteoglycan family, has been recently suggested as a biologically significant mediator of fetal scarless repair. To assess the role of fibromodulin in the tissue remodeling, we constructed an adenoviral vector expressing human fibromodulin cDNA. We evaluated the effect of adenovirus-mediated overexpression of fibromodulin in vitro on transforming growth factors and metalloproteinases in fibroblasts and in vivo on full-thickness incisional wounds in a rabbit model. In vitro, we found that Ad-Fibromodulin induced a decrease of expression of TGF-beta(1) and TGF-beta(2) precursor proteins, but an increase in expression of TGF-beta(3) precursor protein and TGF-beta type II receptor. In addition, fibromodulin overexpression resulted in decreased MMP-1 and MMP-3 protein secretion but increased MMP-2, TIMP-1, and TIMP-2 secretion, whereas MMP-9 and MMP-13 were not influenced by fibromodulin overexpression. In vivo evaluation by histopathology and tensile strength demonstrated that Ad-Fibromodulin administration could ameliorate wound healing in incisional wounds. In conclusion, although the mechanism of scar formation in adult wounds remains incompletely understood, we found that fibromodulin overexpression improves wound healing in vivo, suggesting that fibromodulin may be a key mediator in reduced scarring.


Asunto(s)
Adenoviridae/genética , Cicatriz/prevención & control , Dermis/metabolismo , Proteínas de la Matriz Extracelular/biosíntesis , Fibroblastos/metabolismo , Terapia Genética/métodos , Vectores Genéticos , Proteoglicanos/biosíntesis , Cicatrización de Heridas , Animales , Células Cultivadas , Cicatriz/genética , Cicatriz/metabolismo , Cicatriz/patología , Cicatriz/fisiopatología , Procedimientos Quirúrgicos Dermatologicos , Dermis/citología , Modelos Animales de Enfermedad , Proteínas de la Matriz Extracelular/genética , Fibromodulina , Humanos , Metaloproteinasas de la Matriz Secretadas/metabolismo , Proteínas Serina-Treonina Quinasas , Proteoglicanos/genética , Conejos , Receptor Tipo II de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Resistencia a la Tracción , Factores de Tiempo , Inhibidores Tisulares de Metaloproteinasas/metabolismo , Transfección , Factores de Crecimiento Transformadores/metabolismo , Cicatrización de Heridas/genética
16.
Aviat Space Environ Med ; 79(9): 888-98, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18785358

RESUMEN

BACKGROUND: Orbiter landing data show decrements in pilot performance following spaceflight compared to preflight simulated landings. This study aimed to characterize pilot head-eye coordination during simulated orbiter landings, and relate findings to microgravity-related spatial disorientation. METHODS: Orbiter landings were simulated in an A340-300 simulator flown by six pilots. Turns about the Heading Alignment Circle (HAC) to align the orbiter with the runway were simulated by 45 degrees banking turns. Final approach was simulated with an 11 degrees glide slope from an altitude of 4267 m, with preflare at 610 m and touchdown at 200 kn. Orbiter landings were also performed in the Vertical Motion Simulator (VMS) at NASA Ames by a NASA test pilot. RESULTS: A340: During the HAC maneuver the head and eyes rolled toward the visual horizon with a combined gain of 0.14 of bank angle. Pilots alternated fixation between the instruments and the runway during final approach, almost exclusively focusing on the runway after preflare. Optokinetic nystagmus was observed during rollout. VMS: Head and eye roll tilt when rounding the HAC were of similar magnitude to that observed in the A340. During final approach the Heads-Up Display (HUD) reduced pitch head and eye movement. CONCLUSIONS: Roll tilt of the head and eyes during the HAC tended to align the retina with the visual horizon. Overlaying critical flight information and the approaching runway with the HUD reduced pitch head and eye movement during orbiter final approach in the VMS relative to the A340 (no HUD installed).


Asunto(s)
Adaptación Fisiológica , Ojo , Movimientos de la Cabeza/fisiología , Cabeza/fisiología , Postura/fisiología , Vuelo Espacial , Ingravidez/efectos adversos , Adulto , Femenino , Humanos , Masculino , Fenómenos Fisiológicos Musculoesqueléticos , Orientación , Proyectos Piloto , Reflejo Vestibuloocular/fisiología
17.
Gait Posture ; 26(2): 200-7, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17046261

RESUMEN

A new system for long-term monitoring of gait in Parkinson's disease (PD) has been developed and validated. The characteristics of every stride taken over 10-h epochs were acquired using a lightweight ankle-mounted sensor array that transmitted data wirelessly to a small pocket PC at a rate of 100 Hz. Stride was calculated from the vertical linear acceleration and pitch angular velocity of the leg with an accuracy of 5 cm. Results from PD patients (5) demonstrate the effectiveness of long-term monitoring of gait in a natural environment. The small, variable stride length characteristic of Parkinsonian gait, and fluctuations of efficacy associated with levodopa therapy, such as delayed onset, wearing off, and the 'off/on' effect, could reliably be detected from long-term changes in stride length.


Asunto(s)
Antiparkinsonianos/farmacología , Monitoreo de Drogas/instrumentación , Levodopa/farmacología , Monitoreo Ambulatorio/instrumentación , Enfermedad de Parkinson/tratamiento farmacológico , Adulto , Algoritmos , Antiparkinsonianos/administración & dosificación , Antiparkinsonianos/efectos adversos , Calibración , Computadoras de Mano , Discinesia Inducida por Medicamentos/fisiopatología , Discinesia Inducida por Medicamentos/prevención & control , Electrónica Médica , Estudios de Factibilidad , Femenino , Marcha , Trastornos Neurológicos de la Marcha/etiología , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Levodopa/administración & dosificación , Levodopa/efectos adversos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones
18.
IEEE Trans Biomed Eng ; 64(11): 2719-2728, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28186875

RESUMEN

Freezing of gait (FoG) is common in Parkinsonian gait and strongly relates to falls. Current clinical FoG assessments are patients' self-report diaries and experts' manual video analysis. Both are subjective and yield moderate reliability. Existing detection algorithms have been predominantly designed in subject-dependent settings. In this paper, we aim to develop an automated FoG detector for subject independent. After extracting highly relevant features, we apply anomaly detection techniques to detect FoG events. Specifically, feature selection is performed using correlation and clusterability metrics. From a list of 244 feature candidates, 36 candidates were selected using saliency and robustness criteria. We develop an anomaly score detector with adaptive thresholding to identify FoG events. Then, using accuracy metrics, we reduce the feature list to seven candidates. Our novel multichannel freezing index was the most selective across all window sizes, achieving sensitivity (specificity) of (). On the other hand, freezing index from the vertical axis was the best choice for a single input, achieving sensitivity (specificity) of () for ankle and () for back sensors. Our subject-independent method is not only significantly more accurate than those previously reported, but also uses a much smaller window (e.g., versus ) and/or lower tolerance (e.g., versus ).Freezing of gait (FoG) is common in Parkinsonian gait and strongly relates to falls. Current clinical FoG assessments are patients' self-report diaries and experts' manual video analysis. Both are subjective and yield moderate reliability. Existing detection algorithms have been predominantly designed in subject-dependent settings. In this paper, we aim to develop an automated FoG detector for subject independent. After extracting highly relevant features, we apply anomaly detection techniques to detect FoG events. Specifically, feature selection is performed using correlation and clusterability metrics. From a list of 244 feature candidates, 36 candidates were selected using saliency and robustness criteria. We develop an anomaly score detector with adaptive thresholding to identify FoG events. Then, using accuracy metrics, we reduce the feature list to seven candidates. Our novel multichannel freezing index was the most selective across all window sizes, achieving sensitivity (specificity) of (). On the other hand, freezing index from the vertical axis was the best choice for a single input, achieving sensitivity (specificity) of () for ankle and () for back sensors. Our subject-independent method is not only significantly more accurate than those previously reported, but also uses a much smaller window (e.g., versus ) and/or lower tolerance (e.g., versus ).


Asunto(s)
Acelerometría/métodos , Trastornos Neurológicos de la Marcha/diagnóstico , Enfermedad de Parkinson/diagnóstico , Procesamiento de Señales Asistido por Computador , Anciano , Algoritmos , Femenino , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
PLoS One ; 11(4): e0152469, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27111531

RESUMEN

When increasing ambulation speed in Parkinson's disease, step cadence increases more than stride length, indicating movement scaling difficulties that affect step generation in particular. We investigated whether step length variation when increasing ambulation speed was related to disease progression. Patients with Parkinson's disease (N = 39) and controls (N = 152) performed two timed ambulation tasks: at a 'free' (self-selected) pace and then at 'maximal' speed. The total number of steps (including during turns) and time to complete the task were clinically measured. The relative contribution of step length and cadence to increased ambulation speed was determined using two methods: the ratios of change in step length or in cadence to the change in ambulation speed, and the step length index. While the relative contribution of step length and cadence to increased ambulation speed was independent of age in both control and patient groups, in Parkinson's disease there was a negative correlation between time from diagnosis and the ratio of change in step length to change in ambulation speed (R = 0.54; p = 0.0004) and the step length index (R = 0.56, p = 0.0002). In parallel, there was a positive correlation between time since diagnosis and the ratio of change in cadence to change in ambulation speed (R = 0.57; p = 0.0002). The relative contribution of step length and cadence to increased ambulation speed is age invariant but a marker of Parkinson's disease advancement, and can be easily determined in the clinical setting.


Asunto(s)
Enfermedad de Parkinson/fisiopatología , Caminata , Adulto , Anciano , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/patología , Estudios Retrospectivos
20.
Am J Trop Med Hyg ; 94(6): 1290-8, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27044564

RESUMEN

Autonomic dysfunction is common in Chagas disease and diabetes. Patients with either condition complicated by cardiac autonomic dysfunction face increased mortality, but no clinical predictors of autonomic dysfunction exist. Pupillary light reflexes (PLRs) may identify such patients early, allowing for intensified treatment. To evaluate the significance of PLRs, adults were recruited from the outpatient endocrine, cardiology, and surgical clinics at a Bolivian teaching hospital. After testing for Chagas disease and diabetes, participants completed conventional autonomic testing (CAT) evaluating their cardiovascular responses to Valsalva, deep breathing, and orthostatic changes. PLRs were measured using specially designed goggles, then CAT and PLRs were compared as measures of autonomic dysfunction. This study analyzed 163 adults, including 96 with Chagas disease, 35 patients with diabetes, and 32 controls. PLRs were not significantly different between Chagas disease patients and controls. Patients with diabetes had longer latency to onset of pupil constriction, slower maximum constriction velocities, and smaller orthostatic ratios than nonpatients with diabetes. PLRs correlated poorly with CAT results. A PLR-based clinical risk score demonstrated a 2.27-fold increased likelihood of diabetes complicated by autonomic dysfunction compared with the combination of blood tests, CAT, and PLRs (sensitivity 87.9%, specificity 61.3%). PLRs represent a promising tool for evaluating subclinical neuropathy in patients with diabetes without symptomatic autonomic dysfunction. Pupillometry does not have a role in the evaluation of Chagas disease patients.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/diagnóstico , Enfermedad de Chagas/complicaciones , Diabetes Mellitus/fisiopatología , Retinopatía Diabética/diagnóstico , Reflejo Pupilar , Adulto , Enfermedades del Sistema Nervioso Autónomo/patología , Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Bolivia/epidemiología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/fisiopatología , Retinopatía Diabética/epidemiología , Retinopatía Diabética/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad
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