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result(s) for
"Murray, Ashley"
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Impaired micro-online motor learning processes in individuals with severe anxiety
by
Prashad, Shikha
,
Murray, Ashley
,
Rednoske, Victoria M.
in
anxiety
,
cognitive load
,
implicit motor learning
2026
Anxiety is a prevalent emotional state with physiological and psychological manifestations that can disrupt cognitive processes, such as working memory and attention, leading to impaired motor performance and may also influence motor learning. This study investigated the effect of anxiety on implicit motor learning, visuospatial short-term and working memory, and perceived mental and physical effort. We collected data from 79 individuals using the serial reaction time task, the Corsi block-tapping test, and the NASA-Task Load Index. Participants were grouped based on their anxiety levels measured via the Beck Anxiety Inventory. All groups demonstrated intact implicit motor learning; however, learning processes differed between groups. The severe anxiety group exhibited learning after two-minute breaks between blocks (i.e., micro-offline learning), but did not demonstrate micro-online learning (i.e., improvements in performance while executing the task). In contrast, the minimal anxiety group exhibited both learning processes. Additionally, participants with severe anxiety reported greater frustration and feeling more rushed during the task compared to those with minimal anxiety. Furthermore, the severe anxiety group also demonstrated significantly lower working memory capacity compared to their short-term memory capacity. Together, these results suggest that while individuals with higher anxiety levels demonstrated intact implicit motor learning, they required greater cognitive resources for the learning to occur.
Journal Article
Impaired Clearance and Enhanced Pulmonary Inflammatory/Fibrotic Response to Carbon Nanotubes in Myeloperoxidase-Deficient Mice
by
Kagan, Valerian E.
,
St. Croix, Claudette M.
,
Meade, Aidan D.
in
Animals
,
Antioxidants
,
Atherosclerosis
2012
Advancement of biomedical applications of carbonaceous nanomaterials is hampered by their biopersistence and pro-inflammatory action in vivo. Here, we used myeloperoxidase knockout B6.129X1-MPO (MPO k/o) mice and showed that oxidation and clearance of single walled carbon nanotubes (SWCNT) from the lungs of these animals after pharyngeal aspiration was markedly less effective whereas the inflammatory response was more robust than in wild-type C57Bl/6 mice. Our results provide direct evidence for the participation of MPO - one of the key-orchestrators of inflammatory response - in the in vivo pulmonary oxidative biodegradation of SWCNT and suggest new ways to control the biopersistence of nanomaterials through genetic or pharmacological manipulations.
Journal Article
Patient-Centered Communication (PCC) scale: Psychometric analysis and validation of a health survey measure
by
Jensen, Roxanne E.
,
Trivedi, Neha
,
Blake, Kelly D.
in
Adult
,
Anxiety
,
Biology and Life Sciences
2022
Patient-centered communication (PCC) is one important component of patient-centered care and seen as a goal for most clinical encounters. Previous research has shown that higher PCC is related to an increase in healthy behaviors and less morbidity, among other outcomes. Given its importance, the National Cancer Institute (NCI) commissioned a monograph in 2007 to synthesize the existing literature on PCC and determine measurement objectives and strategies for measuring this construct, with a particular focus on cancer survivors. Based on this effort, a seven-item PCC scale was included on the Health Information National Trends Survey (HINTS), a probability-based survey of the US adult population. This study used HINTS data collected in 2018 to evaluate the psychometric properties of the PCC scale for the general US adult population including measures of reliability and validity.
Through an exploratory factor analysis, the seven-item PCC scale was shown to be unidimensional with good internal consistency (Cronbach's alpha = .92). A confirmatory factor analysis verified the factor structure. Other construct validity metrics included known groups and discriminant validity. Known group comparisons were conducted for several sociodemographic factors and health self-efficacy confirming a priori assumptions. Discriminant validity tests with measures of social support and anxiety/depression showed relatively weak associations.
The psychometric properties of this scale demonstrate its scientific utility for both surveillance research and other smaller-scale studies. Given its association with many health outcomes, it can also be used to better understand the dynamics in a clinical encounter.
Journal Article
Costs and Willingness to Pay for Pit Latrine Emptying Services in Kigali, Rwanda
by
Murray, Ashley
,
Sklar, Rachel
,
Burt, Zachary
in
Consumer Behavior
,
Contract Services - economics
,
Contract Services - methods
2019
Kigali, Rwanda lacks a centralized sewer system, which leaves residents to choose between on-site options; the majority of residents in informal settlements use pit latrines as their primary form of sanitation. When their pits fill, the pits are either sealed, or emptied; emptying is often done by hand and then dumped in the environment, putting the residents and the broader population at risk of infectious disease outbreaks. In this paper, we used revealed and stated preference models to: (1) estimate the demand curve for improved emptying services; and, (2) evaluate household preferences and the willingness to pay (WTP) for different attributes of improved emptying services. We also quantify the costs of improved service delivery at different scales of production. The study included 1167 households from Kigali, Rwanda across 30 geographic clusters. Our results show that, at a price of US $79 per pit, 15% of all the pits would be emptied by improved emptying services, roughly the current rate of manual emptying. Grouping empties by neighborhood and ensuring that each truck services an average of four households per day could reduce the production costs to US$ 44 per empty, ensuring full cost coverage at that price. At a lower price of US $24, we estimate that the sealing of pits might be fully eliminated, with full coverage of improved emptying services for all pits; this would require a relatively small subsidy of US$ 20 per empty. Our results show that households had strong preferences for fecal sludge (FS) treatment, formalized services (which include worker protections), and distant disposal. The results from the study indicate a few key policies and operational strategies that can be used for maximizing the inclusion of low-income households in safely managed sanitation services, while also incorporating household preferences and participation.
Journal Article
Carbon nanotubes degraded by neutrophil myeloperoxidase induce less pulmonary inflammation
by
Kagan, Valerian E.
,
Shi, Jingwen
,
Klein-Seetharaman, Judith
in
631/250/256
,
639/925/357/73
,
639/925/928
2010
We have shown previously that single-walled carbon nanotubes can be catalytically biodegraded over several weeks by the plant-derived enzyme, horseradish peroxidase
1
. However, whether peroxidase intermediates generated inside human cells or biofluids are involved in the biodegradation of carbon nanotubes has not been explored. Here, we show that hypochlorite and reactive radical intermediates of the human neutrophil enzyme myeloperoxidase catalyse the biodegradation of single-walled carbon nanotubes
in vitro
, in neutrophils and to a lesser degree in macrophages. Molecular modelling suggests that interactions of basic amino acids of the enzyme with the carboxyls on the carbon nanotubes position the nanotubes near the catalytic site. Importantly, the biodegraded nanotubes do not generate an inflammatory response when aspirated into the lungs of mice. Our findings suggest that the extent to which carbon nanotubes are biodegraded may be a major determinant of the scale and severity of the associated inflammatory responses in exposed individuals.
A type of peroxidase enzyme found in certain white blood cells can degrade single-walled carbon nanotubes into products that do not cause inflammation in the lungs of mice, suggesting that the severity of toxic responses of carbon nanotubes may depend on the extent of its degradation.
Journal Article
Factoring-in agglomeration of carbon nanotubes and nanofibers for better prediction of their toxicity versus asbestos
2012
Background
Carbon nanotubes (CNT) and carbon nanofibers (CNF) are allotropes of carbon featuring fibrous morphology. The dimensions and high aspect ratio of CNT and CNF have prompted the comparison with naturally occurring asbestos fibers which are known to be extremely pathogenic. While the toxicity and hazardous outcomes elicited by airborne exposure to single-walled CNT or asbestos have been widely reported, very limited data are currently available describing adverse effects of respirable CNF.
Results
Here, we assessed pulmonary inflammation, fibrosis, oxidative stress markers and systemic immune responses to respirable CNF in comparison to single-walled CNT (SWCNT) and asbestos. Pulmonary inflammatory and fibrogenic responses to CNF, SWCNT and asbestos varied depending upon the agglomeration state of the particles/fibers. Foci of granulomatous lesions and collagen deposition were associated with dense particle-like SWCNT agglomerates, while no granuloma formation was found following exposure to fiber-like CNF or asbestos. The average thickness of the alveolar connective tissue - a marker of interstitial fibrosis - was increased 28 days post SWCNT, CNF or asbestos exposure. Exposure to SWCNT, CNF or asbestos resulted in oxidative stress evidenced by accumulations of 4-HNE and carbonylated proteins in the lung tissues. Additionally, local inflammatory and fibrogenic responses were accompanied by modified systemic immunity, as documented by decreased proliferation of splenic T cells
ex vivo
on day 28 post exposure. The accuracies of assessments of effective surface area for asbestos, SWCNT and CNF (based on geometrical analysis of their agglomeration) versus estimates of mass dose and number of particles were compared as predictors of toxicological outcomes.
Conclusions
We provide evidence that effective surface area along with mass dose rather than specific surface area or particle number are significantly correlated with toxicological responses to carbonaceous fibrous nanoparticles. Therefore, they could be useful dose metrics for risk assessment and management.
Journal Article
Strain-Specific Variability in Viral Kinetics, Cytokine Response, and Cellular Damage in Air–Liquid Cultures of Human Nasal Organoids After Infection with SARS-CoV-2
by
Blutt, Sarah E.
,
Schultz, Emily M.
,
Avadhanula, Vasanthi
in
airway organoids
,
Cells
,
Comparative analysis
2025
SARS-CoV-2 variants have demonstrated distinct epidemiological patterns and clinical presentations throughout the COVID-19 pandemic. Understanding variant-specific differences at the respiratory epithelium is crucial for understanding their pathogenesis. Here, we utilized human nasal organoid air–liquid interface (HNO-ALI) cell cultures to compare the viral replication kinetics, innate immune response, and epithelial damage of six different strains of SARS-CoV-2 (B.1.2, WA, Alpha, Beta, Delta, and Omicron). All variants replicated efficiently in HNO-ALIs, but with distinct replication kinetic patterns. The Delta variant exhibited delayed replication kinetics, achieving a steady state at 6 days post-infection compared to 3 days for other variants. Cytokine analysis revealed robust pro-inflammatory and chemoattractant responses (IL-6, IL-8, IP-10, CXCL9, and CXCL11) in WA1, Alpha, Beta, and Omicron infections, while Delta significantly dampened the innate immune response, with no significant induction of IL-6, IP-10, CXCL9, or CXCL11. Immunofluorescence and H&E analysis showed that all variants caused significant ciliary damage, though WA1 and Delta demonstrated less destruction at early time points (3 days post-infection). Together, these data show that, in our HNO-ALI model, the Delta variant employs a distinct “stealth” strategy characterized by delayed replication kinetics and epithelial cell innate immune evasion when compared to other variants of SARS-CoV-2, potentially explaining a mechanism that the Delta variant can use for its enhanced transmissibility and virulence observed clinically. Our findings demonstrate that variant-specific differences at the respiratory epithelium could explain some of the distinct clinical presentations and highlight the utility of the HNO-ALI system for the rapid assessment of emerging variants.
Journal Article
Oxidative Stress and Dermal Toxicity of Iron Oxide Nanoparticles In Vitro
by
Kagan, Valerian E.
,
Shvedova, Anna A.
,
Murray, Ashley R.
in
Biochemistry
,
Biological and Medical Physics
,
Biological Transport
2013
A number of commercially available metal/metal oxide nanoparticles (NPs) such as superparamagnetic iron oxide (SPION) are utilized by the medical field for a wide variety of applications. These NPs may able to induce dermal toxicity via their physical nature and reactive surface properties. We hypothesize that SPION may be toxic to skin via the ability of particles to be internalized and thereby initiate oxidative stress, inducing redox-sensitive transcription factors affecting/leading to inflammation. Due to the skin’s susceptibility to UV radiation, it is also of importance to address the combined effect of UVB and NPs co-exposure. To test this hypothesis, the effects of dextran-coated SPION of different sizes (15–50 nm) and manufacturers (MicroMod, Rostock-Warnemunde, Germany and KTH-Royal Institute of Technology, Stockholm, Sweden) were evaluated in two cell lines: normal human epidermal keratinocytes (HEK) and murine epidermal cells (JB6 P
+
). HEK cells exposed to 20 nm (KTH and MicroMod) had a decrease in viability, while the 15 and 50 nm particles were not cytotoxic. HEK cells were also capable of internalizing the KTH particles (15 and 20 nm) but not the MicroMod SPION (20 and 50 nm). IL-8 and IL-6 were also elevated in HEK cells following exposure to SPION. Exposure of JB6 P
+
cells to all SPIONs evaluated resulted in activation of AP-1. Exposure to SPION alone was not sufficient to induce NF-κB activation; however, co-exposure with UVB resulted in significant NF-κB induction in cells exposed to 15 and 20 nm KTH SPION and 50 nm MicroMod particles. Pre-exposure of JB6 P
+
cells to UVB followed by NPs induced a significant depletion of glutathione, release of cytokines, and cell damage as assessed by release of lactate dehydrogenase. Altogether, these data indicate that co-exposure to UVB and SPIONs was associated with induction of oxidative stress and release of inflammatory mediators. These results verify the need to thoroughly evaluate the adverse effects of UVB when evaluating dermal toxicity of engineered NPs on skin.
Journal Article
Development of a Measure of Fearful Implicit Associations with Dental Stimuli in Youth
2023
Youth with dental anxiety are at an increased risk of poor oral health but current tools used to identify dental anxiety in children in clinical settings are hampered by several limitations. This study assessed the psychometric properties of a measure of implicit associations with dental stimuli, the Affective Misattribution Procedure for dental stimuli (AMP-D) in 68 youth between the ages of 9 and 17 years. Measures of self-reported dental anxiety and parental perceptions of child dental anxiety were also administered. The internal consistency of the AMP-D was high (KR-20 = 0.96) and 1-week test-retest reliability was in the acceptable range (r = 0.75). The AMP-D was correlated with self-reported dental anxiety, providing evidence of construct validity. The psychometric properties of the AMP-D suggest it could be a useful tool in identifying youth with dental anxiety, particularly when concerns regarding self-representation may compromise the validity of self-reported anxiety.
Journal Article
“We hide…”: Perceptions of HIV Risk Among Black and Latino MSM in New York City
by
Sutton, Madeline Y.
,
Murray, Ashley
,
Gaul, Zaneta
in
Adolescent
,
Black or African American - psychology
,
Disease prevention
2018
Black and Latino men who have sex with men (BLMSM) are disproportionately infected with HIV; they comprised 66% of HIV diagnoses among men who have sex with men (MSM) in the United States in 2015. Risk factors for HIV infection among BLMSM include a high community prevalence of diagnosed and undiagnosed HIV/STDs, and dense sex partner networks. Perceptions of HIV risk among BLMSM were explored to inform HIV prevention efforts. During 2011–2012, semistructured interviews were conducted with BLMSM in New York City. Using computer-assisted thematic analyses (NVivo), transcribed interview responses to questions regarding HIV risk for main themes were examined. Interview data were available for 108 BLMSM: 86% Black, 13% Latino, 26% aged 18–24 years, 59% self-identified as “gay,” and 33% self-identified as “bisexual.” The main emergent theme was stigma. Subthemes related to stigma included: (a) homophobia in the Black and Latino community, (b) fear of losing support from family and friends, and (c) lack of support leading to low self-esteem. Addressing the stigma felt by BLMSM may be an important strategy to facilitate improved HIV prevention efforts, HIV care and treatment, and to decrease HIV-related disparities.
Journal Article