Browsing by Author "Crandell, Ian"

Now showing 1 - 7 of 7
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    Behavioural intentions in response to a potential menthol cigarette sales ban: a survey examining smokers in Washington, DC public housing
    Dearfield, Craig T.; Horn, Kimberly; Crandell, Ian; Bernat, Debra H. (Bmj Publishing Group, 2022-07)
    Objectives Local, national and international policies are being proposed to ban the sale of menthol-flavoured tobacco products. With more bans being implemented, it is increasingly important to understand reactions to these bans among smokers of low socioeconomic status. This study examined public housing residents' behavioural intentions if menthol-flavoured cigarettes were no longer sold. Setting 15 District of Columbia Housing Authority properties between March 2019 and March 2021. Participants 221 District of Columbia Housing Authority residents ages 18-80 years who reported smoking menthol cigarettes (83.3% African-American/black). Primary and secondary outcomes Cigarette quitting and switching intentions due to a hypothetical menthol-flavoured cigarette sales ban. Results Nearly one-half (48.0%) of residents said they intended to quit cigarette use if menthol-flavoured products were no longer sold, while 27.2% were unsure if they would quit, and 24.9% reported they would not quit. Older residents (OR 0.94 per year, 95% CI 0.91 to 0.97), senior/disabled building versus family building residents (OR 0.50, 95% CI 0.25 to 0.97), those who smoked within 30 min of waking (OR 0.48, 95% CI 0.23 to 0.98) and daily smokers (OR 0.42, 95% CI 0.21 to 0.84) had lower odds of reporting quit intentions associated with a menthol ban. Of those not intending to quit, 40.7% reported they would switch to non-menthol cigarettes, 20.4% to another non-menthol product, 13.0% to menthol e-cigarettes and 20.4% to another menthol product. Conclusions Results suggest banning the sale of menthol-flavoured products has the potential to impact cigarette smoking cessation. Nearly three-quarters of smokers in public housing indicated a possibility of quitting smoking because of a menthol cigarette ban. Bans that include all flavours in all tobacco products may be most effective for facilitating overall tobacco cessation.
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    The conduction velocity-potassium relationship in the heart is modulated by sodium and calcium
    King, D. Ryan; Entz, Michael, II; Blair, Grace A.; Crandell, Ian; Hanlon, Alexandra L.; Lin, Joyce; Hoeker, Gregory S.; Poelzing, Steven (2021-03)
    The relationship between cardiac conduction velocity (CV) and extracellular potassium (K+) is biphasic, with modest hyperkalemia increasing CV and severe hyperkalemia slowing CV. Recent studies from our group suggest that elevating extracellular sodium (Na+) and calcium (Ca2+) can enhance CV by an extracellular pathway parallel to gap junctional coupling (GJC) called ephaptic coupling that can occur in the gap junction adjacent perinexus. However, it remains unknown whether these same interventions modulate CV as a function of K+. We hypothesize that Na+, Ca2+, and GJC can attenuate conduction slowing consequent to severe hyperkalemia. Elevating Ca2+ from 1.25 to 2.00 mM significantly narrowed perinexal width measured by transmission electron microscopy. Optically mapped, Langendorff-perfused guinea pig hearts perfused with increasing K+ revealed the expected biphasic CV-K+ relationship during perfusion with different Na+ and Ca2+ concentrations. Neither elevating Na+ nor Ca2+ alone consistently modulated the positive slope of CV-K+ or conduction slowing at 10-mM K+; however, combined Na+ and Ca2+ elevation significantly mitigated conduction slowing at 10-mM K+. Pharmacologic GJC inhibition with 30-mu M carbenoxolone slowed CV without changing the shape of CV-K+ curves. A computational model of CV predicted that elevating Na+ and narrowing clefts between myocytes, as occur with perinexal narrowing, reduces the positive and negative slopes of the CV-K+ relationship but do not support a primary role of GJC or sodium channel conductance. These data demonstrate that combinatorial effects of Na+ and Ca2+ differentially modulate conduction during hyperkalemia, and enhancing determinants of ephaptic coupling may attenuate conduction changes in a variety of physiologic conditions.
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    Deepening Our Understanding of COVID-19 Vaccine Decision-Making amongst Healthcare Workers in Southwest Virginia, USA Using Exploratory and Confirmatory Factor Analysis
    Bendetson, Jesse; Swann, Mandy C.; Lozano, Alicia; West, Jennifer; Hanlon, Alexandra L.; Crandell, Ian; Jatta, Maimuna; Schleupner, Charles J.; Baffoe-Bonnie, Anthony W. (MDPI, 2023-02-27)
    Vaccine hesitancy amongst healthcare workers (HCWs) has been a major challenge throughout the COVID-19 pandemic. While many studies have identified HCW characteristics and specific attitudes associated with COVID-19 vaccine hesitancy, researchers are still working towards developing a holistic understanding of the psychological constructs that influence COVID-19 vaccine decision-making in this population. Between 15 March and 29 March 2021, we distributed an online survey assessing individual characteristics and vaccine-related perceptions to employees of a not-for-profit healthcare system in Southwest Virginia (N = 2459). We then performed exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to describe patterns of vaccine-related thought amongst HCWs and identify latent psychometric constructs involved in vaccine decision-making. The goodness of model fit was assessed using the Tucker–Lewis Index (TLI), the Comparative Fit Index (CFI), and the Root Mean Square Error of Approximation (RMSEA). Internal consistency and reliability of each factor were assessed using Cronbach’s alpha. EFA identified four latent psychometric constructs: Lack of trust in the COVID-19 vaccine; Anti-science sentiment; Adverse side-effects; and Situational risk assessment. The goodness of EFA model fit was adequate (TLI > 0.90, RMSEA ≤ 0.08) with acceptable internal consistency and reliability for three of four factors (Cronbach’s alpha > 0.70). The CFA model also had adequate goodness of fit (CFI > 0.90, RMSEA ≤ 0.08). We believe the psychometric constructs identified in this study can provide a useful framework for interventions to improve vaccine uptake amongst this critical population.
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    Low Xanthophylls, Retinol, Lycopene, and Tocopherols in Grey and White Matter of Brains with Alzheimer's Disease
    Dorey, C. Kathleen; Gierhart, Dennis; Fitch, Karlotta A.; Crandell, Ian; Craft, Neal E. (IOS Press, 2022-08-16)
    Background: Oxidative stress contributes to pathogenesis and progression of Alzheimer's disease (AD). Higher levels of the dietary antioxidants- carotenoids and tocopherols- are associated with better cognitive functions and lower risk for AD, and lower levels of multiple carotenoids are found in serum and plasma of patients with AD. Although brains donated by individuals with mild cognitive impairment had significantly lower levels of lutein and beta-carotene, previous investigators found no significant difference in carotenoid levels of brains with AD and cognitively normal brains. Objective: This study tested the hypothesis that micronutrients are significantly lower in donor brains with AD than in healthy elderly brains. Methods: Samples of donor brains with confirmed AD or verified health were dissected into grey and white matter, extracted with organic solvents and analyzed by HPLC. Results: AD brains had significantly lower levels of lutein, zeaxanthin, anhydrolutein, retinol, lycopene, and alpha-tocopherol, and significantly increased levels of XMiAD, an unidentified xanthophyll metabolite. No meso-zeaxanthin was detected. The overlapping protective roles of xanthophylls, carotenes, α- and γ-tocopherol are discussed. Conclusion: Brains with AD had substantially lower concentrations of some, but not all, xanthophylls, carotenes, and tocopherols, and several-fold higher concentrations of an unidentified xanthophyll metabolite increased in AD (XMiAD).
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    Low Xanthophylls, Retinol, Lycopene, and Tocopherols in Grey and White Matter of Brains with Alzheimer’s Disease
    Dorey, C. Kathleen; Gierhart, Dennis; Fitch, Karlotta A.; Crandell, Ian; Craft, Neal E. (IOS Press, 2023-06)
    Background: Oxidative stress contributes to pathogenesis and progression of Alzheimer’s disease (AD). Higher levels of the dietary antioxidants— carotenoids and tocopherols— are associated with better cognitive functions and lower risk for AD, and lower levels of multiple carotenoids are found in serum and plasma of patients with AD. Although brains donated by individuals with mild cognitive impairment had significantly lower levels of lutein and beta-carotene, previous investigators found no significant difference in carotenoid levels of brains with AD and cognitively normal brains. Objective: This study tested the hypothesis that micronutrients are significantly lower in donor brains with AD than in healthy elderly brains. Methods: Samples of donor brains with confirmed AD or verified health were dissected into grey and white matter, extracted with organic solvents and analyzed by HPLC. Results: AD brains had significantly lower levels of lutein, zeaxanthin, anhydrolutein, retinol, lycopene, and alpha-tocopherol, and significantly increased levels of XMiAD, an unidentified xanthophyll metabolite. No meso-zeaxanthin was detected. The overlapping protective roles of xanthophylls, carotenes, α- and γ-tocopherol are discussed. Conclusion: Brains with AD had substantially lower concentrations of some, but not all, xanthophylls, carotenes, and tocopherols, and several-fold higher concentrations of an unidentified xanthophyll metabolite increased in AD (XMiAD).
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    Outlier Detection for Sensor Systems (ODSS): A MATLAB Macro for Evaluating Microphone Sensor Data Quality
    Vasta, Robert; Crandell, Ian; Millican, Anthony J.; House, Leanna L.; Smith, Eric (MDPI, 2017-10-13)
    Microphone sensor systems provide information that may be used for a variety of applications. Such systems generate large amounts of data. One concern is with microphone failure and unusual values that may be generated as part of the information collection process. This paper describes methods and a MATLAB graphical interface that provides rapid evaluation of microphone performance and identifies irregularities. The approach and interface are described. An application to a microphone array used in a wind tunnel is used to illustrate the methodology.
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    Smoking cessation intentions and attempts one year after the federally mandated smoke-free housing rule
    Horn, Kimberly; Dearfield, Craig T.; Johnson, Sallie Beth; Krost, Kevin; Patino, Sofia Rincon Gallardo; Gray, Tiffany; Crandell, Ian; Bernat, Debra H. (Elsevier, 2021-12)
    The present study examines public housing residents' smoking cessation intentions, expectancies, and attempts one year after implementation of the Department of Housing and Urban Development's mandatory smoke-free rule in public housing. The sample includes 233 cigarette smokers, ages 18-80, who reside in the District of Columbia Housing Authority. Data collection occurred between March and August 2019. Descriptive statistics, chi-square, and Wilcoxon two-sample test analyses assessed smoking cessation intentions, expectancies, and attempts across resident demographics and characteristics. Findings showed 17.2% of residents reported not thinking about quitting, 39.1% reported thinking about quitting, and 48.6% reported thinking about quitting specifically because of the rule. Residents ages 60-80 were more likely to consider quitting because of the rule, compared to residents ages 18-59. Of those thinking of quitting, 58.6% were sure they could quit if they tried. Those thinking of quitting due to the rule (62.0%) were more likely to have made at least one quit attempt in the past 3 months than those i not attributinging thinking of quitting to the rule. Res Residents trying to quit reported an average of 2.7 attempts in the last 3 months;; most perceived evidence-based cessation supports as not helpful. A A majority reported thinking about quitting and attempting to quit but continuing to smoke, indicating a significant gap between intent to quit and successfully quitting. Results suggest that the rule positively influenced smoking behaviors. However, additional interventions are needed to assist public housing residents with successfully quitting smoking.