Browsing by Author "Patterson, Rita M."
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Item A pilot case series for concurrent validation of inertial measurement units to motion capture in individuals who use unilateral lower-limb prostheses(Sage Publications, 2023-07-13) Finco, M. G.; Patterson, Rita M.; Moudy, Sarah C.INTRODUCTION: Inertial measurement units (IMUs) may be viable options to collect gait data in clinics. This study compared IMU to motion capture data in individuals who use unilateral lower-limb prostheses. METHODS: Participants walked with lower-body IMUs and reflective markers in a motion analysis space. Sagittal plane hip, knee, and ankle waveforms were extracted for the entire gait cycle. Discrete points of peak flexion, peak extension, and range of motion were extracted from the waveforms. Stance times were also extracted to assess the IMU software's accuracy at detecting gait events. IMU and motion capture-derived data were compared using absolute differences and root mean square error (RMSE). RESULTS: Five individuals (n = 3 transtibial; n = 2 transfemoral) participated. IMU prosthetic limb data was similar to motion capture (RMSE: waveformItem Analysis of Approach and Motion Velocities in Dominant Hands While Performing Daily Activities(2015-03) Juarez, Jessica K.; Young, Carolyn; Bugnariu, Nicoleta L.; Patterson, Rita M.Analysis of Approach and Motion Velocities in Dominant Hands While Performing Daily Activities Previous studies have shown individual force sensors to be a simple means of providing feedback about the environment to a robot. Combining the data of velocity in two phases (approach and motion) from a touch sensitive surface glove can provide insight into the neural processes that govern muscle movements during approach, pushing, and pulling of an object. The analysis of these interactions may be used to streamline the motions of a robot to simulate the average adult human’s movement while performing simple tasks. Data from dominant hand positions and velocities from ten people was collected using a motion capture system (Motion Analysis Corp, Santa Rosa, CA). There were five females and five males with ages 23-51. Quantitative data of both motion and velocity was collected on five trials and averaged across the cohort for analysis. The average minimum velocity during approach for a push movement was 0.546 meters/second, 0.579 meters/second, and 0.632 meters/second for a cylinder weight of three, five, ten pounds respectively. Trends show that as weight increases, so does the minimum velocity of approach in the palm position. Future analysis of these data will include providing information for building simulated and eventually physical human-robot interaction systems to aid in daily activities.Item Autism Spectrum Disorder with and Without Co-Occurring Attention Deficit Hyperactivity Disorder: An Analysis of Pathways to Diagnosis and Intervention in a National Sample(2018-05) Thomi, Morgan S.; Mathew, Stephen O.; Miller, Haylie L.; Patterson, Rita M.; Lovely, Rehana S.Autism Spectrum Disorder (ASD) is diagnosed in 1 out of 68 children. Recent changes to diagnostic guidelines permit clinicians to assign co-occurring diagnoses of ASD and Attention Deficit-Hyperactivity Disorder (ADHD). It is important for researchers and clinicians to be aware of groups vulnerable to delayed or incomplete diagnosis. In this retrospective review of data from the CDC Survey of Pathways to Diagnostics and Services (SPDS) and the National Survey of the Diagnosis and Treatment of ADHD and Tourette Syndrome (DTAT), we sought to assess the impact of race, ethnicity, sex, poverty level, and diagnosing provider type on age of first concern and age of final diagnosis in children diagnosed with ASD, ADHD, and ASD+ADHD. We predicted that age of first concern and age of final diagnosis would vary by sex, race, poverty level, identifier of first symptoms, provider type, and comorbidities. Parents/guardians of 5,959 children aged 3-17 completed the surveys; in the current sample, 2,966 cases were from DTAT and 2,993 were from SPDS. We used a series of ANOVAs to assess differences in the variables of interest by group. Age of first concern was significantly impacted (p [less than] 0.05) by Race, Race x Poverty Level, and Race x Poverty Level x Sex for the ASD+ADHD group. Age of final diagnosis was not significantly impacted (p [greater than] 0.05) by Poverty Level, Race x Poverty Level, and Sex x Race x Poverty Level for the ASD group. Identifier of first symptoms significantly impacted (p [less than] 0.05) age of first concern for all groups, while identifier of first concerns only significantly impacted (p [less than] 0.05) the ASD and ADHD groups. Post-hoc analyses revealed specific patterns of risk. Specific combinations of demographic factors increase vulnerability for later diagnosis. These findings suggest that provider- and patient-centered education is needed to increase surveillance in at-risk populations.Item Comparing Balance in Patients with Fall History(2024-03-21) Roccaforte, Emma; Wahl, Joseph; McGrath, Jessica; Kennedy, Shawn; Patterson, Rita M.Purpose: With falls being the leading cause of mortality with injury, risk factors of falls should be explored further (Lohman). Postural Sway is a method in which you can quantify balance and postural control. Increase in postural sway is shown to be correlated with error in postural control modalities. (Dewan). Having a quantifiable fall-risk metric that can be quickly obtained, could prevent falls, and thereby reduce mortality and surgical interventions necessary. This experiment explores the effect of fall history on postural sway using the Bertec force plate’s measurement of change of pressure, CoP. Methods/Materials: Family Medicine and Geriatric patient participants on a volunteer basis were asked to perform two 30 second intervals of quiet standing on a Bertec force plate as an additional vital sign. Two conditions were performed on firm surfaces: with eyes open (EO) and with eyes closed (EC). Patients were asked to stare at a target for the EO portion and stand still on the force plate for 30 seconds while data was collected. After this, the patient was asked to close their eyes and stand still for another 30 seconds for the eyes closed portion. Postural sway was measured in accordance with CoP using the Clinical Test of Sensory Integration and Balance (mCTSIB) protocol, which describes quiet standing under various conditions to assess fall risk and balance problems. A group of 22 patients with a documented history of a fall was compared against 129 patients without a documented history of a fall. The values of the Range of the CoP in anterior-posterior (AP) direction/axis and medial-lateral (ML) direction/axis were compared using a 2-tail T-test. The values of standard deviation and average of the Radial Distance (RD), the displacement of the CoP points from the center of the stabiligram, a graphical representation of the movements of a person’s quiet standing, were also compared using a 2-tail T-test. Significant values at both conditions, EO and EC, were noted at p < 0.05. Results: The Range of the CoP (AP) was significantly increased in both conditions, EO and EC. The Range of the CoP (ML) was significantly increased in EC, but nonsignificant in EO. The Average RD was significant in EC but nonsignificant in EO, with the Standard Deviation RD with a significant increase in both EO and EC. Conclusion: These findings suggest that there is increased sway in patients with a reported history of a fall compared to those without. This could be a result of error in the vestibular, somatosensory, or visual systems. These errors could point to an increased fall risk. Future studies should investigate the effects these systems have on fall risk as there was more consistent statistical difference of the groups during the eyes closed portion. Some limitations include small sample size, other factors altering sway, and potential non reported fallers in the control group. The ability to measure fall risk quickly and objectively through a simple and non-invasive method like postural sway could prove instrumental in preventing falls with further studies.Item Concurrent surface electromyography and force myography classification during times of prosthetic socket shift and user fatigue(Sage Publications, 2017-08-01) Sanford, Joe; Patterson, Rita M.; Popa, Dan O.Objective: Surface electromyography has been a long-standing source of signals for control of powered prosthetic devices. By contrast, force myography is a more recent alternative to surface electromyography that has the potential to enhance reliability and avoid operational challenges of surface electromyography during use. In this paper, we report on experiments conducted to assess improvements in classification of surface electromyography signals through the addition of collocated force myography consisting of piezo-resistive sensors. Methods: Force sensors detect intrasocket pressure changes upon muscle activation due to changes in muscle volume during activities of daily living. A heterogeneous sensor configuration with four surface electromyography-force myography pairs was investigated as a control input for a powered upper limb prosthetic. Training of two different multilevel neural perceptron networks was employed during classification and trained on data gathered during experiments simulating socket shift and muscle fatigue. Results: Results indicate that intrasocket pressure data used in conjunction with surface EMG data can improve classification of human intent and control of a powered prosthetic device compared to traditional, surface electromyography only systems. Significance: Additional sensors lead to significantly better signal classification during times of user fatigue, poor socket fit, as well as radial and ulnar wrist deviation. Results from experimentally obtained training data sets are presented.Item EFFECTIVNESS OF BALANCE TRAINING WITH VIRTUAL REALITY AND VIBROTACTILE DEVICE IN DIABETIC PATIENTS(2014-03) Behan, Francis; Jafari, Roozbeh; Patterson, Rita M.; Bugnariu, NicoletaPurpose (a): Patients with diabetic peripheral neuropathy experience different degrees of sensory loss in their feet and tend to rely heavily on visual inputs to maintain their balance. This is an efficient coping strategy for as long as they can attend to the placements of their feet, but becomes a high risk of falls when they have to visually attend to something else, like crossing a street or a conversation. The purpose of this research is to assess the effectiveness of a training program designed to improve balance through sensory reweighting based on the principles of stochastic resonance and using virtual reality (VR). Moreover, biomarkers for diabetic control and neuro-protection pre- and post- sensory retraining will be studied to identify possible correlations between balance control and specific lab values. In addition, membrane androgen receptor (mAR ) has been linked to poor cognitive performance in animal models and this link will be examined in terms of balance control in the human subjects. Methods (b): Subjects with peripheral neuropathy due to diabetes undergo 6 one hour long training sessions in which they practice increasingly more challenging task of balance and walking while their visual attention is engaged by the VR. During training subjects were fitted with vibratory devices placed above the level of sensory loss (around the ankles). The intended to enhance somatosensory perception in the feet vibration was constant and sub-threshold. At visit 1 and 8, Pre- and Post- training assessments of balance and gait function as well as blood values for mAR, follicle stimulating hormone, estradiol, estrogen, C reactive protein, glucose, and a lipid panel. Results (c): To date two subjects have been enrolled in the study and one diabetic subject has completed the entire 8 weeks training protocol. Comparison of pre- and post-training revealed an improved balance function expressed by increased anterior and lateral center of pressure movement (ability to reach forward and laterally without losing balance) and increased walking speed. At the end of the training subject was able to maintain a straight walking trajectory even in the presence of visual inputs entraining lateral movements. Conclusions (d): Preliminary results show that sensory retraining with VR and vibratory device is feasible in diabetic subjects and holds promise for improvement of balance due to an increased ability to integrate all sensory inputs available and a decreased reliance on visual inputs.Item Effects of Osteopathic Manipulative Treatment on Parkinsonian Gait: A Statistical Parametric Mapping Analysis(2021-05) Terrell, Zachary T.; Patterson, Rita M.; Moudy, Sarah; Hensel, KendiIntroduction/Background: Tens of thousands of people are diagnosed with Parkinson's disease (PD) each year, making it the second most common neurodegenerative disorder. PD results in a variety of gait disturbances that increase the fall risk of those afflicted. The overarching goal for this project is to examine the efficacy of Osteopathic Manipulative Treatment (OMT) and Osteopathic Cranial Manipulative Medicine (OCMM) in improving Parkinsonian gait. Objective: The purpose of this study was to compare joint range of motion (ROM) and joint angle waveforms before and after OMT to determine the effects of OMT and OCMM on Parkinsonian gait, as well as to compare the relative effects of each treatment protocol. We hypothesized that the application of a single OMT protocol on adults with PD will acutely increase joint ROM, and the addition of OCMM to the OMT treatment protocol will further improve gait kinematics. Methods: An 18-camera motion analysis system was used in conjunction with 54 reflective markers on the body to capture three-dimensional position data in a short treadmill walking trial before and after the application of a whole-body (OMT-WB), neck-down (OMTND), or sham OMT protocol. Ankle, knee, and hip joint ROM and waveforms in the sagittal plane during the gait cycle were compared before and after treatment, and across experimental groups. Results: No significant differences were found in baseline ROM and joint angle waveforms of the hip, knee, and ankle joints across experimental groups, or in post-treatment joint waveforms across experimental groups. Knee ROM increased significantly following OMT-ND and OMT-WB protocols (p=0.018, p=0.032). Waveform analysis revealed no significant differences at the hip, knee, or ankle joints. Discussion/Conclusion: Comparison of baseline measurements validates participant randomization and an increase in sagittal knee ROM in individuals with PD following OMT and OCMM may have important implications for decreasing potential fall risk. However, waveform analysis shows no significant change in gait pattern as evidenced by sagittal joint angles following OMT-WB, OMT-ND, or SHAM treatments.Item FUNCTIONAL ASSESSMENT OF BALANCE AND GAIT IN TRANSTIBIAL AMPUTEES USING K2 VS. K3 PROSTHETIC FEET(2014-03) Hidrogo, Joe III; Stevens, Gordon; Patterson, Rita M.; Bugnariu, NicoletaPurpose (a): The K-Level classification of prosthetic feet is used in conjunction with a similar classification of functional level of amputees to determine which prosthetic feet will be prescribed and reimbursed. Individuals classified as ambulatory level 2, receive a K2 prosthetic foot and not the higher functioning K3 prosthetic. This provides less technology to the patients who need it most, limiting them in their current and potential abilities. We aimed to evaluate gait and balance in transtibial amputees ambulating with either a lower cost K2 prosthetic foot or the more functional dynamic response K3 prosthesis. We hypothesized that K3 prosthesis will show immediate improvements in gait and balance, and a 2- week trial with a K3 would increase functional level and quality of life. Methods (b): Research participants with transtibial amputations secondary to diabetes or vascular disease were fitted by a certified Prostestist-Orthotist with either a K2 or K3 prosthesis. On the initial study visit the quality of life baseline established using standardized questionnaires for reintegration after amputation. Also, the V-gait CAREN (Computer Assisted Rehabilitation Environment Network) system was used to establish baseline balance and gait measures and immediate effects of switching type of prosthesis. The participants were then randomized into groups for a 2-week trial period of wearing a prosthetic foot (K2 or K3) that was either at, above or below the current functional level of the amputee. Post-trial measurements of balance, gait, and quality of life were reassessed. Results (c): To date two subjects have been enrolled in the study. Both subjects expressed limitations and changes in quality of life due to amputation. Balance was compromised in conditions of dual tasks and subjects had significant difficulties walking up and down ramps illustrated by changes in lower limb kinematics. When tested with a K2 prosthetic, one subject was unable to maintain baseline gait velocity even on level ground. Conclusions (d): Preliminary results confirm that K3 prosthetic foot provides additional benefits for balance and gait function compared to K2. Providing higher level prosthetic feet to patients who are classified at lower functional level could improve their balance, prevent serious costly injuries caused by trips and falls, and facilitate transition to higher functional status. Therefore, it is pertinent that the proper K level prosthetic be prescribed.Item Hearing Loss Contributes to Balance Difficulties in both Younger and Older Adults(iMedPub LTD, 2018-04-09) Kowalewski, Victoria; Patterson, Rita M.; Hartos, Jessica; Bugnariu, NicoletaObjective: The number of steps required to regain balance is an easily obtainable clinical outcome measure. This study assessed whether number of steps during loss of balance could identify older adults with hearing loss who have balance deficits. We aimed to answer two questions: 1) Does hearing loss negatively affect the ability to regain balance, as reflected by an increased number of steps needed to respond to a perturbation while simultaneously attending to speech-in-noise; and 2) Do hearing aids improve balance control, reflected by a decrease in number of steps needed to regain balance? Methods: 20 young adults and 20 older adults with normal hearing, and 19 older adults with hearing loss performed an auditory-balance dual-task. Participants were asked to listen and repeat back sentences from a standardized audiology test, while simultaneously responding to backward surface translations. Outcome measures were performed on the auditory test and number of steps needed to regain balance. Repeated measures ANCOVA models were run in using group, time, hearing levels, and perturbation levels as predictors. Results: Auditory scores confirmed difficulty hearing speech-in-noise in older adults with hearing loss and no hearing aids, and in young and older adults with normal hearing and simulated hearing loss. Results showed that group, auditory and balance conditions are significantly related to both outcomes measures and time is not significant for steps. Older adults with hearing loss had a significant increase in number of steps needed to regain balance compared to young adults and older adults with normal hearing. Conclusion: Number of steps may be an appropriate clinical assessment tool for identifying fall risk in older adults with hearing loss. Further research needs to be performed to identify proper assessments and treatment interventions for older adults with hearing loss who have balance deficits.Item ISCHEMIA-INDUCED REDUCTION OF SOMATOSENSORY INPUT DECREASES BALANCE; ADDED VIBRATORY NOISE PARTIALLY RESTORES FUNCTION(2014-03) Rose, Gemma; Nordon-Craft, Amy; Jaffari, Roozbeh; Patterson, Rita M.; Bugnariu, NicoletaIn this project we mimicked loss of sensation in the feet, commonly seen in diabetic patients, through an ischemic protocol, a reduction of circulation in young healthy adults. This loss of sensation resulted in changes in balance like those seen in diabetic patients that are prone to falls. We then tested the effectiveness of a vibratory device to improve balance. Purpose (a): We investigated the feasibility of using vibrotactile biofeedback to improve balance in healthy young adults in which the somatosensory information from their feet has been temporarily decreased. We hypothesized that though stochastic resonance, vibratory noise applied just proximal to a region of reduced somatosensation will improve ability to maintain balance. Methods (b): Ten healthy young individuals aged 18 to 25 years old gave informed consent and participated in this study. We experimentally induced “somatosensory loss” in non-diabetic young healthy subjects using pressure cuffs wrapped around the ankles, kept inflated at 220-250mmHg for 35 min. A vibrotactile biofeedback system was positioned just above the pressure cuffs. An array of vibrotactile actuators, under a Texas Instruments MSP430 microcontroller, produced vibration at two frequencies: a barely perceptible low frequency and a high vibration frequency. Data was collected at baseline before the pressure cuffs were inflated and during the last 15 minutes of the ischemic protocol under three conditions: no vibration, low frequency and high frequency vibrations. Outcome measures included: centre of pressure (COP) variability with subjects standing with feet side by side/ one foot, with eyes open/closed; plantar surface pressure sensation and vibratory threshold evaluated with Siemens Monofilaments and Rydel-Seiffer tuning fork, respectively. Results (c): In single limb support with eyes closed, ischemia increases the COP variability (p=.01) and the addition of vibrotactile feedback at both frequencies decreases it baseline values. Plantar surface pressure sensation threshold increased after ischemia (p=.03) and was decreased with the added vibrotactile feedback. The vibratory extension threshold measured at the hallux IP joint was decreased by ischemia (p. Conclusions (d): The ischemic protocol produced balance changes in healthy young adults. The vibratory biofeedback was able to partially compensate for the experimental induced sensory loss and improve balance function. Most diabetic patients become “visually dependent” due to peripheral neuropathy, and may experience falls at night or when they turn their head or talk to someone while walking. The next step of this research is to test the effectiveness of a vibrotactile biofeedback to decrease the risk for falls in diabetic adults with peripheral neuropathies.Item OSTEOPATHIC MANIPULATIVE TREATMENT IN HISPANIC PATIENTS: A RETROSPECTIVE CHART STUDY(2014-03) Patel, Asmani; Patterson, Rita M.; Mason, DavidPurpose (a): To understand the incidence of Hispanic patients presenting to the Osteopathic Manipulative Medicine (OMM) Clinic, and to compare their demographics to the Hispanic and other ethnic populations in Tarrant County. Methods (b): Data for this retrospective chart study was collected for Hispanics patients who had visited the OMM Clinic from June 25, 2012 to June 25, 2013. Patient charts were reviewed for the following data: demographics, somatic dysfunction, osteopathic manipulative treatment, and assessment/diagnosis. Data for demographics of the population in Tarrant County was obtained through HealthyNorthTexas.Org. Results (c): The data for patients attending the OMM Clinic showed that 75.9% of patients were White, Non-Hispanic and 7.6% of the patients were Hispanic. In Tarrant County, 50.7% of the population is White, Non-Hispanic and 27.4% of the population is Hispanic. 82.5% of the White, Non-Hispanic population and 47.5% of the Hispanic population has health insurance. When comparing the data from the OMM Clinic and Tarrant County, it is evident that 41.8% of the White, Non-Hispanics in Tarrant County should be coming to the OMM Clinic based on health insurance status, and 13% of the Hispanics should be coming to the OMM Clinic. The Hispanics come into the OMM Clinic at a rate of 1:10 (1 Hispanic patient for every 10 White, Non-Hispanic patients). However, Hispanics should be coming to the OMM Clinic at a rate of 1:3. Conclusions (d): The study established that the Hispanic population does not come into the OMM Clinic at the same rate as the White, Non-Hispanic population does, despite having health insurance. Therefore, it is necessary to educate the Hispanic population on the benefits of Osteopathic Manipulative Treatment (OMT).Item Quantifying Musculoskeletal and Biomechanical Symmetry to Identify Injury and Fall Risks in Individuals Who Use Unilateral Lower-Limb Prostheses(2022-12) Finco, Malaka G.; Menegaz, Rachel A.; Patterson, Rita M.Individuals who use lower-limb prostheses have increased risks of developing overuse injuries and experiencing falls compared to the general population. This is often attributed to individuals loading, or weighting, their prosthetic limb less than their intact limb. Quantifying musculoskeletal and biomechanical symmetry between prosthetic and intact limbs could help clinicians evaluate risks of developing overuse injuries and experiencing falls. However, these relationships have not been determined. The objective of this dissertation is to quantify musculoskeletal and biomechanical symmetry and determine their relationships to overuse injuries and falls in individuals with unilateral lower-limb loss. This objective has two specific aims: 1) evaluate musculoskeletal symmetry associated with risks of developing overuse injuries, and 2) determine the relationship between wearable sensor-derived walking symmetry values and falls. Musculoskeletal symmetry was quantified in skeletal properties (e.g. fracture risk via dual x-ray absorptiometry), hip and knee joint space (e.g. osteoarthritis via x-rays), and thigh muscle architecture (e.g. atrophy via cross-sectional area) in four anatomical donors and thirty post-mortem CT scans. Biomechanical symmetry was quantified in twenty-two individuals who use unilateral lower-limb prostheses. Wearable sensors called inertial measurement units were compared to the gold standard of motion capture in the first five individuals. The relationship between number of falls, clinical outcome measures, and gait symmetry will be assessed to determine if gait symmetry could supplement clinical outcome measures to evaluate fall risk. Impaired musculoskeletal symmetry suggests amputated limbs, particularly those with diabetes, had higher indications of distal femur fracture risk and more thigh muscle atrophy compared to intact limbs. Compared to healthy and diabetic control groups, individuals with amputation had higher indications of osteoarthritis and muscle atrophy bilaterally. Biomechanical studies suggest data derived from inertial measurement units were comparable to motion capture, and the Four Square Step test was associated with 12-month retrospective falls. Findings could help clinicians proactively evaluate overuse injury and fall risks in this population.Item Soft robotic devices for hand rehabilitation and assistance: a narrative review(BioMed Central Ltd., 2018-02-17) Chu, Chia-Ye; Patterson, Rita M.Introduction: The debilitating effects on hand function from a number of a neurologic disorders has given rise to the development of rehabilitative robotic devices aimed at restoring hand function in these patients. To combat the shortcomings of previous traditional robotics, soft robotics are rapidly emerging as an alternative due to their inherent safety, less complex designs, and increased potential for portability and efficacy. While several groups have begun designing devices, there are few devices that have progressed enough to provide clinical evidence of their design's therapeutic abilities. Therefore, a global review of devices that have been previously attempted could facilitate the development of new and improved devices in the next step towards obtaining clinical proof of the rehabilitative effects of soft robotics in hand dysfunction. Methods: A literature search was performed in SportDiscus, Pubmed, Scopus, and Web of Science for articles related to the design of soft robotic devices for hand rehabilitation. A framework of the key design elements of the devices was developed to ease the comparison of the various approaches to building them. This framework includes an analysis of the trends in portability, safety features, user intent detection methods, actuation systems, total DOF, number of independent actuators, device weight, evaluation metrics, and modes of rehabilitation. Results: In this study, a total of 62 articles representing 44 unique devices were identified and summarized according to the framework we developed to compare different design aspects. By far, the most common type of device was that which used a pneumatic actuator to guide finger flexion/extension. However, the remainder of our framework elements yielded more heterogeneous results. Consequently, those results are summarized and the advantages and disadvantages of many design choices as well as their rationales were highlighted. Conclusion: The past 3 years has seen a rapid increase in the development of soft robotic devices for hand rehabilitative applications. These mostly preclinical research prototypes display a wide range of technical solutions which have been highlighted in the framework developed in this analysis. More work needs to be done in actuator design, safety, and implementation in order for these devices to progress to clinical trials. It is our goal that this review will guide future developers through the various design considerations in order to develop better devices for patients with hand impairments.Item The Effect of Hearing Loss on Balance Control(2018-05) Kowalewski, Victoria C.; Bugnariu, Nicoleta L.; Patterson, Rita M.; Liu, Hao; Smith, Michael L.We investigated the contribution of auditory inputs to balance control in healthy young adults and older adults with normal hearing by simulating hearing loss, as well as in older adult with hearing loss by testing with and without hearing aids. Twenty healthy young adults with normal hearing, twenty older adults with normal hearing, and twenty older adults with hearing aids completed single- and dual- tasks consisting of a standardized audiology test (BKB-SIN) and maintaining standing balance in response to surface translations. Participants performed an auditory task of repeating back sentences from a standardized audiological test, the Bamford-Kowal-Bench Speech-In-Noise (BKB-SIN), played through wireless noise-cancelling headphones under randomized normal hearing and simulated hearing loss conditions or through surrounding speakers under hearing aid or no hearing aid condition. Simulated hearing loss was achieved using Adobe Audition software and a FFT logarithmic curve to manipulate sound volume and frequencies of standardized sentences according to age-related moderate hearing loss documented in literature. Backward surface translation perturbations inducing a forward loss of balance were synchronized with the auditory task and presented randomly at three levels (0m/s2, 2m/s2, and 5 m/s2). Primary outcome measures included: maximum Center of Pressure ? Center of Mass (COP-COM) distance in response to perturbation during the first compensatory step, reaction time for initiating the first compensatory step, number of steps after loss of balance, and performance on the BKB-SIN. Repeated measures ANOVA were conducted for each dependent variable with respect to perturbation level and auditory condition. Results show reaction time decreases, maximum COP-COM distance increases, and number of steps increases as perturbation level increases across all groups. BKB-SIN scores and reaction time were significantly worse under the simulated hearing loss condition. Hearing aids significantly improved BKB-SIN scores, but not balance scores. Hearing loss affects reactive balance control, particularly while simultaneously attending to auditory tasks. Older adults maintain the ability to initiate compensatory steps, but they require an increase number of steps to regain balance. Individuals with hearing loss may be at greater risk of falling compared to individuals with normal hearing due to age-related cognitive and neurodegenerative changes associated with hearing loss.Item Transcriptome and functional profiles of R/G-HIV+ human astrocytes: Implications for shock or lock therapies in the brain(2020-05) Edara, Venkata Viswanadh; Borgmann, Kathleen; Berg, Rance E.; Krishnamoorthy, Raghu R.; Mathew, Porunelloor A.; Yang, Shaohua; Patterson, Rita M.A significant number of people living with human immunodeficiency virus (HIV) suffer from HIV-associated neurocognitive disorders (HAND). Many previous studies investigating HIV in astrocytes as a heterogenous population have established the relevance of astrocytes to HIV-associated neuropathogenesis. However, these studies were unable to differentiate the state of infection, i.e. active or restricted, or to evaluate how this affects astrocyte biology. In this study a pseudotyped doubly labelled fluorescent reporter R/G-HIV-1 was used to identify and enrich restricted and active populations of HIV+ astrocytes based on the viral promoter activity. Here we report, the majority of human astrocytes restricted R/G-HIV-1 gene expression early during infection and were resistant to reactivation by vorinostat and interleukin-1β. However, actively infected astrocytes were inducible, leading to increased expression of viral proteins upon reactivation. R/G-HIV-1 infection also significantly decreased cell proliferation and glutamate clearance ability of astrocytes, which may contribute to excitotoxicity. Moreover, transcriptome analyses to compare gene expression patterns of astrocytes harboring active vs restricted long terminal repeats revealed that the gene expression patterns were similar, and the active population demonstrated more widespread and robust changes. Our data suggest that harboring the HIV genome profoundly alters astrocyte biology and strategies that keep the virus latent (e.g. Block and Lock), or those that reactivate the latent virus (e.g. Shock and Kill) may be detrimental to astrocyte function and possibly augment their deleterious contributions to HAND.