The Experts below are selected from a list of 19713 Experts worldwide ranked by ideXlab platform

Russell S Richardson - One of the best experts on this subject based on the ideXlab platform.

  • the passive Leg Movement technique for assessing vascular function the impact of baseline blood flow
    Experimental Physiology, 2021
    Co-Authors: Katherine L Shields, Russell S Richardson, Ryan M Broxterman, Catherine L Jarrett, A V Bisconti, Soung Hun Park
    Abstract:

    NEW FINDINGS What is the central question of this study? The passive Leg Movement (PLM) assessment of vascular function utilizes the blood flow response in the common femoral artery (CFA): what is the impact of baseline CFA blood flow on the PLM response? What is the main finding and its importance? Although an attenuated PLM response is not an obligatory consequence of increased baseline CFA blood flow, increased blood flow through the deep femoral artery will diminish the response. Care should be taken to ensure that a genuine baseline Leg blood flow is obtained prior to performing a PLM vascular function assessment. ABSTRACT The passive Leg Movement (PLM) assessment of vascular function utilizes the blood flow response in the common femoral artery (CFA). This response is primarily driven by vasodilation of the microvasculature downstream from the deep (DFA) and, to a lesser extent, the superficial (SFA) femoral artery, which facilitate blood flow to the upper and lower Leg, respectively. However, the impact of baseline CFA blood flow on the PLM response is unknown. Therefore, to manipulate baseline CFA blood flow, PLM was performed with and without upper and lower Leg cutaneous heating in 10 healthy subjects, with blood flow (ultrasound Doppler) and blood pressure (finometer) assessed. Baseline blood flow was significantly increased in the CFA (∼97%), DFA (∼109%) and SFA (∼78%) by upper Leg heating. This increase in baseline CFA blood flow significantly attenuated the PLM-induced total blood flow in the DFA (∼62%), which was reflected by a significant fall in blood flow in the CFA (∼49%), but not in the SFA. Conversely, lower Leg heating increased blood flow in the CFA (∼68%) and SFA (∼160%), but not in the DFA. Interestingly, this increase in baseline CFA blood flow only significantly attenuated the PLM-induced total blood flow in the SFA (∼60%), and not in the CFA or DFA. Thus, although an attenuated PLM response is not an obligatory consequence of an increase in baseline CFA blood flow, an increase in baseline blood flow through the DFA will diminish the PLM response. Therefore, care should be taken to ensure that a genuine baseline Leg blood flow is obtained prior to performance of a PLM vascular function assessment.

  • the passive Leg Movement technique for assessing vascular function defining the distribution of blood flow and the impact of occluding the lower Leg
    Experimental Physiology, 2019
    Co-Authors: Katherine L Shields, Ryan M Broxterman, Catherine L Jarrett, A V Bisconti, Soung Hun Park, Russell S Richardson
    Abstract:

    NEW FINDINGS What is the central question of this study? What is the distribution of the hyperaemic response to passive Leg Movement (PLM) in the common (CFA), deep (DFA) and superficial (SFA) femoral arteries? What is the impact of lower Leg cuff-induced blood flow occlusion on this response? What is the main finding and its importance? Of the total blood that passed through the CFA, the majority was directed to the DFA and this was unaffected by cuffing. As a small fraction does pass through the SFA to the lower Leg, cuffing during PLM should be considered to emphasize the thigh-specific hyperaemia. ABSTRACT It has yet to be quantified how passive Leg Movement (PLM)-induced hyperaemia, an index of vascular function, is distributed beyond the common femoral artery (CFA), into the deep femoral (DFA) and the superficial femoral (SFA) arteries, which supply blood to the thigh and lower Leg, respectively. Furthermore, the impact of cuffing the lower Leg, a common practice, especially with drug infusions during PLM, on the hyperaemic response is, also, unknown. Therefore, PLM was performed with and without cuff-induced blood flow (BF) occlusion to the lower Leg in 10 healthy subjects, with BF assessed by Doppler ultrasound. In terms of BF distribution during PLM, of the 380 ± 191 ml of blood that passed through the CFA, 69 ± 8% was directed to the DFA, while only 31 ± 8% passed through the SFA. Cuff occlusion of the lower Leg significantly attenuated the PLM-induced hyperaemia through the SFA (∼30%), which was reflected by a fall in BF through the CFA (∼20%), but not through the DFA. Additionally, cuff occlusion significantly attenuated the PLM-induced peak change in BF (BFΔpeak ) in the SFA (324 ± 159 to 214 ± 114 ml min-1 ), which was, again, reflected in the CFA (1019 ± 438 to 833 ± 476 ml min-1 ), but not in the DFA. Thus, the PLM-induced hyperaemia predominantly passes through the DFA and this was unaltered by cuffing. However, as a small fraction of the PLM-induced hyperaemia does pass through the SFA to the lower Leg, cuffing the lower Leg during PLM should be considered to emphasize thigh-specific hyperaemia in the PLM assessment of vascular function.

  • corp ultrasound assessment of vascular function with the passive Leg Movement technique
    Journal of Applied Physiology, 2017
    Co-Authors: Russell S Richardson, Jayson R Gifford
    Abstract:

    As dysfunction of the vascular system is an early, modifiable step in the progression of many cardiovascular diseases, there is demand for methods to monitor the health of the vascular system nonin...

  • single passive Leg Movement induced hyperemia a simple vascular function assessment without a chronotropic response
    Journal of Applied Physiology, 2017
    Co-Authors: Massimo Venturelli, Gwenael Layec, Joel D Trinity, Ryan M Broxterman, Corey R Hart, Russell S Richardson
    Abstract:

    Using the single passive Leg Movement (PLM) technique, a variant of the vascular function assessment PLM, we have identified a novel peripheral vascular assessment method that is more easily perfor...

  • Vascular function assessed by passive Leg Movement and flow-mediated dilation: initial evidence of construct validity.
    American journal of physiology. Heart and circulatory physiology, 2016
    Co-Authors: Matthew J Rossman, H. Jonathan Groot, Ryan S. Garten, Melissa A. H. Witman, Russell S Richardson
    Abstract:

    This study explores the relationship between a novel assessment of vascular health, passive Leg Movement (PLM), and an established measure, flow-mediated dilation (FMD), to aid in the interpretatio...

Joel D Trinity - One of the best experts on this subject based on the ideXlab platform.

Jayson R Gifford - One of the best experts on this subject based on the ideXlab platform.

Ryan M Broxterman - One of the best experts on this subject based on the ideXlab platform.

  • the passive Leg Movement technique for assessing vascular function the impact of baseline blood flow
    Experimental Physiology, 2021
    Co-Authors: Katherine L Shields, Russell S Richardson, Ryan M Broxterman, Catherine L Jarrett, A V Bisconti, Soung Hun Park
    Abstract:

    NEW FINDINGS What is the central question of this study? The passive Leg Movement (PLM) assessment of vascular function utilizes the blood flow response in the common femoral artery (CFA): what is the impact of baseline CFA blood flow on the PLM response? What is the main finding and its importance? Although an attenuated PLM response is not an obligatory consequence of increased baseline CFA blood flow, increased blood flow through the deep femoral artery will diminish the response. Care should be taken to ensure that a genuine baseline Leg blood flow is obtained prior to performing a PLM vascular function assessment. ABSTRACT The passive Leg Movement (PLM) assessment of vascular function utilizes the blood flow response in the common femoral artery (CFA). This response is primarily driven by vasodilation of the microvasculature downstream from the deep (DFA) and, to a lesser extent, the superficial (SFA) femoral artery, which facilitate blood flow to the upper and lower Leg, respectively. However, the impact of baseline CFA blood flow on the PLM response is unknown. Therefore, to manipulate baseline CFA blood flow, PLM was performed with and without upper and lower Leg cutaneous heating in 10 healthy subjects, with blood flow (ultrasound Doppler) and blood pressure (finometer) assessed. Baseline blood flow was significantly increased in the CFA (∼97%), DFA (∼109%) and SFA (∼78%) by upper Leg heating. This increase in baseline CFA blood flow significantly attenuated the PLM-induced total blood flow in the DFA (∼62%), which was reflected by a significant fall in blood flow in the CFA (∼49%), but not in the SFA. Conversely, lower Leg heating increased blood flow in the CFA (∼68%) and SFA (∼160%), but not in the DFA. Interestingly, this increase in baseline CFA blood flow only significantly attenuated the PLM-induced total blood flow in the SFA (∼60%), and not in the CFA or DFA. Thus, although an attenuated PLM response is not an obligatory consequence of an increase in baseline CFA blood flow, an increase in baseline blood flow through the DFA will diminish the PLM response. Therefore, care should be taken to ensure that a genuine baseline Leg blood flow is obtained prior to performance of a PLM vascular function assessment.

  • the role of the endothelium in the hyperemic response to passive Leg Movement looking beyond nitric oxide
    American Journal of Physiology-heart and Circulatory Physiology, 2021
    Co-Authors: Joel D Trinity, Ryan M Broxterman, Jayson R Gifford, Oh Sung Kwon, Andrew C Kithas, Jay R Hydren
    Abstract:

    Passive Leg Movement (PLM) evokes a highly nitric oxide (NO)-mediated hyperemic response and may provide a novel evaluation of vascular function. The contributions of endothelium-dependent vasodila...

  • the passive Leg Movement technique for assessing vascular function defining the distribution of blood flow and the impact of occluding the lower Leg
    Experimental Physiology, 2019
    Co-Authors: Katherine L Shields, Ryan M Broxterman, Catherine L Jarrett, A V Bisconti, Soung Hun Park, Russell S Richardson
    Abstract:

    NEW FINDINGS What is the central question of this study? What is the distribution of the hyperaemic response to passive Leg Movement (PLM) in the common (CFA), deep (DFA) and superficial (SFA) femoral arteries? What is the impact of lower Leg cuff-induced blood flow occlusion on this response? What is the main finding and its importance? Of the total blood that passed through the CFA, the majority was directed to the DFA and this was unaffected by cuffing. As a small fraction does pass through the SFA to the lower Leg, cuffing during PLM should be considered to emphasize the thigh-specific hyperaemia. ABSTRACT It has yet to be quantified how passive Leg Movement (PLM)-induced hyperaemia, an index of vascular function, is distributed beyond the common femoral artery (CFA), into the deep femoral (DFA) and the superficial femoral (SFA) arteries, which supply blood to the thigh and lower Leg, respectively. Furthermore, the impact of cuffing the lower Leg, a common practice, especially with drug infusions during PLM, on the hyperaemic response is, also, unknown. Therefore, PLM was performed with and without cuff-induced blood flow (BF) occlusion to the lower Leg in 10 healthy subjects, with BF assessed by Doppler ultrasound. In terms of BF distribution during PLM, of the 380 ± 191 ml of blood that passed through the CFA, 69 ± 8% was directed to the DFA, while only 31 ± 8% passed through the SFA. Cuff occlusion of the lower Leg significantly attenuated the PLM-induced hyperaemia through the SFA (∼30%), which was reflected by a fall in BF through the CFA (∼20%), but not through the DFA. Additionally, cuff occlusion significantly attenuated the PLM-induced peak change in BF (BFΔpeak ) in the SFA (324 ± 159 to 214 ± 114 ml min-1 ), which was, again, reflected in the CFA (1019 ± 438 to 833 ± 476 ml min-1 ), but not in the DFA. Thus, the PLM-induced hyperaemia predominantly passes through the DFA and this was unaltered by cuffing. However, as a small fraction of the PLM-induced hyperaemia does pass through the SFA to the lower Leg, cuffing the lower Leg during PLM should be considered to emphasize thigh-specific hyperaemia in the PLM assessment of vascular function.

  • delineating the age related attenuation of vascular function evidence supporting the efficacy of the single passive Leg Movement as a screening tool
    Journal of Applied Physiology, 2019
    Co-Authors: Jay R Hydren, Joel D Trinity, Ryan M Broxterman, Jayson R Gifford, Oh Sung Kwon, Andrew C Kithas
    Abstract:

    Single passive Leg Movement (sPLM) exhibits the prerequisite qualities of a valid screening test for peripheral vascular dysfunction. sPLM displayed an age-related reduction in the peripheral hemod...

  • single passive Leg Movement assessment of vascular function contribution of nitric oxide
    Journal of Applied Physiology, 2017
    Co-Authors: Joel D Trinity, Ryan M Broxterman, Jayson R Gifford, Oh Sung Kwon, Andrew C Kithas, Jay R Hydren
    Abstract:

    Passive Leg Movement (PLM), a novel assessment of vascular function, has been simplified to a single PLM (sPLM), thereby increasing the clinical utility of this technique. However, the role of nitr...

Beth A. Smith - One of the best experts on this subject based on the ideXlab platform.

  • Leg Movement rate before and after a caregiver provided intervention for infants at risk of developmental disability a pilot study
    Physical & Occupational Therapy in Pediatrics, 2021
    Co-Authors: Marcelo Rosales, Beth A. Smith, Weiyang Deng, Ryota Nishiyori, Douglas L Vanderbilt
    Abstract:

    Our purpose was to assess daily Leg Movement rate before and after a caregiver-provided in-home intervention for infants at risk for developmental disability. We also assessed adherence and quality...

  • using socially assistive robot feedback to reinforce infant Leg Movement acceleration
    Robot and Human Interactive Communication, 2021
    Co-Authors: Weiyang Deng, Marcelo Rosales, Barbara Sargent, Nina S Bradley, Lauren Klein, Jose Carlos Pulido, Maja J Mataric, Beth A. Smith
    Abstract:

    Learning Movement control is a fundamental process integral to infant development. However, it is still unclear how infants learn to control Leg Movement. This work explores the potential of using socially assistive robots to provide real-time adaptive reinforcement learning for infants. Ten 6 to 8-month old typically-developing infants participated in a study where a robot provided reinforcement when the infant’s right Leg acceleration fell within the range of 9 to 20 m/s2. If infants increased the proportion of Leg accelerations in this band, they were categorized as "performers". Six of the ten participating infants were categorized as performers; the performer subgroup increased the magnitude of acceleration, proportion of target acceleration for right Leg, and ratio of right/left Leg acceleration peaks within the target acceleration band and their right Legs increased Movement intensity from the baseline to the contingency session. The results showed infants specifically adjusted their right Leg acceleration in response to a robot- provided reward. Further study is needed to understand how to improve human-robot interaction policies for personalized interventions for young infants.

  • Leg Movement rate pre and post kicking intervention in infants with down syndrome
    Physical & Occupational Therapy in Pediatrics, 2021
    Co-Authors: Rahil N Khasgiwale, Beth A. Smith, Julia Looper
    Abstract:

    AIM Children with Down syndrome (DS) have delayed development and atypical Movements including kicking. We hypothesized that a kicking intervention would significantly increase Leg Movement rate. METHODS Nine infants, 3-5 months old, with DS used a commercially available toy that encouraged kicking. The intervention was administered in their home for 20 minutes, 5 days a week, for 8 weeks. Leg Movement rate was measured using Opal wearable sensors before and after the intervention. At post-test, a secondary analysis compared infants with DS to infants with typical development (TD). RESULTS Average Leg Movement rate increased significantly from pre to post intervention, from 2253 to 2645 Movements per hour of awake time (p = 0.049). Compared to data from nine infants with TD, infants with DS had a significantly lower Movement rate post intervention (p = 0.002). CONCLUSION The infants with DS demonstrated a higher Leg Movement rate following an in-home kicking intervention.

  • how many days are necessary to represent typical daily Leg Movement behavior for infants at risk of developmental disabilities
    Sensors, 2020
    Co-Authors: Weiyang Deng, Beth A. Smith, Ryota Nishiyori, Douglas L Vanderbilt
    Abstract:

    Background: Movement characteristics can differentiate between infants at risk and infants with typical development. However, it is unknown how many days are needed to accurately represent typical daily behavior for infants at risk of developmental disabilities when using wearable sensors. To consider the balance between participant burden and the amount of data collected and optimizing the efficiency of data collection, our study determined (1) how many days were necessary to represent typical Movement behavior for infants at risk of developmental disabilities and (2) whether Movement behavior was different on weekend days and weekdays. Methods: We used Opal wearable sensors to collect at least 5 days of 11 infants’ Leg Movement data. The standard (average of 5 days) was compared with four methods (average of the first 1/2/3/4 days) using the Bland–Altman plots and the Spearman correlation coefficient. We also compared the data from the average of 2 weekend days to the average of the first 2 weekdays for 8 infants. Results: The Spearman correlation coefficient comparing the average of the first 2 days of data and the standards were all above 0.7. The absolute differences between them were all below 10% of the standards. The Bland–Altman plots showed more than 90% of the data points comparing the average of 2 days and the standards fell into the limit of agreement for each variable. The absolute difference between weekend days and weekdays for the Leg Movement rate, duration, average acceleration, and peak acceleration was 15.2%, 1.7%, 6.8% and 6.3% of the corresponding standard, respectively. Conclusion: Our results suggest 2 days is the optimal amount of data to represent typical daily Leg Movement behavior of infants at risk of developmental disabilities while minimizing participant burden. Further, Leg Movement behavior did not differ distinctly across weekend days and weekdays. These results provide supportive evidence for an efficient amount of data collections when using wearable sensors to evaluate Movement behavior in infants at risk of developmental disabilities.

  • how many days are necessary to represent an infant s typical daily Leg Movement behavior using wearable sensors
    Physical Therapy, 2019
    Co-Authors: Weiyang Deng, Ivan A Trujillopriego, Beth A. Smith
    Abstract:

    Background Characteristics of Movement can differentiate infants with typical development and infants with or at risk of developmental disabilities. We used wearable sensors to measure infants' typical Movement patterns in the natural environment. Objective Our objectives were to determine (1) how many days were sufficient to represent an infant's typical daily performance, and (2) if there was a difference in performance between weekdays and weekend days. Design This was a prospective, observational study. Methods We used wearable sensors to collect 7 consecutive days of data for Leg Movement activity, from 10 infants with typical development (1-5 months old). We identified each Leg Movement, and its average acceleration, peak acceleration, and duration. Bland-Altman plots were used to compare the standard (average of 7 days) with 6 options (1 day, the average of days 1 and 2, through the average of days 1 through 6). Additionally, the average of the first 2 weekdays was compared with the average of 2 weekend days. Results The absolute difference between the average of the first 2 days and the standards fell below 10% of the standards (Movement rate = 8.5%; duration = 3.7%; average acceleration = 2.8%; peak acceleration = 3.8%, respectively). The mean absolute difference between weekdays and weekends for Leg Movement rate, duration, average acceleration, and peak acceleration was 11.6%, 3.7%, 7.2%, and 7.3% of the corresponding standard. Limitations The small sample size and age range limit extrapolation of the results. Conclusions Our results suggest the best option is to collect data for 2 consecutive days and that Movement did not differ between weekdays and weekend days. Our results will inform the clinical measurement of full-day infant Leg Movement for neuromotor assessment and outcome purposes.