Browsing by Subject "cardiovascular"

Now showing 1 - 5 of 5
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    An afferent explanation for sexual dimorphism in the aortic baroreflex of rat
    (American Physiological Society (APS), 2014-09-15) Santa Cruz Chavez, Grace C.; Li, Bai-Yan; Glazebrook, Patricia A.; Kunze, Diana L.; Schild, John H.; Department of Biomedical Engineering, Purdue School of Engineering and Technology, IUPUI
    Sex differences in baroreflex (BRx) function are well documented. Hormones likely contribute to this dimorphism, but many functional aspects remain unresolved. Our lab has been investigating a subset of vagal sensory neurons that constitute nearly 50% of the total population of myelinated aortic baroreceptors (BR) in female rats but less than 2% in male rats. Termed “Ah,” this unique phenotype has many of the nonoverlapping electrophysiological properties and chemical sensitivities of both myelinated A-type and unmyelinated C-type BR afferents. In this study, we utilize three distinct experimental protocols to determine if Ah-type barosensory afferents underlie, at least in part, the sex-related differences in BRx function. Electron microscopy of the aortic depressor nerve (ADN) revealed that female rats have less myelin (P < 0.03) and a smaller fiber cross-sectional area (P < 0.05) per BR fiber than male rats. Electrical stimulation of the ADN evoked compound action potentials and nerve conduction profiles that were markedly different (P < 0.01, n = 7 females and n = 9 males). Selective activation of ADN myelinated fibers evoked a BRx-mediated depressor response that was 3–7 times greater in female (n = 16) than in male (n = 17) rats. Interestingly, the most striking hemodynamic difference was functionally dependent upon the rate of myelinated barosensory fiber activation. Only 5–10 Hz of stimulation evoked a rapid, 20- to 30-mmHg reduction in arterial pressure of female rats, whereas rates of 50 Hz or higher were required to elicit a comparable depressor response from male rats. Collectively, our experimental results are suggestive of an alternative myelinated baroreceptor afferent pathway in females that may account for, at least in part, the noted sex-related differences in autonomic control of cardiovascular function.
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    ARTE index revisited: linking biomarkers of cardiometabolic health with free-living physical activity in postmenopausal women
    (American Physiological Society, 2022-04-01) Carter, Stephen J.; Baranauskas, Marissa N.; Singh,, Harshvardhan; Martins, Catia; Hunter, Gary R.; Exercise & Kinesiology, School of Health and Human Sciences
    Activity-related energy expenditure (AEE) correlates with physical activity volume; however, between-person differences in body size and walking economy (net V̇o2) can influence AEE. The ratio of total energy expenditure (TEE) and resting energy expenditure (REE) estimates physical activity level (PAL) relative to body mass, yet does not account for variance in walking economy. The activity-related time equivalent (ARTEwalk) circumvents such constraints by adjusting for individual-specific walking economy. Herein, we compared AEE, PAL, and ARTEwalk index in a cohort (n = 81) of postmenopausal women while examining possible associations with biomarkers of cardiometabolic health. Secondary analyses were performed on postmenopausal women dichotomized above/below age group 50th percentile for body fat percent. TEE was reduced by 10% for the thermogenesis of digestion wherein AEE was calculated by subtracting REE from adjusted TEE. PAL was calculated as the ratio of TEE/REE. AEE was divided by the mean net energy expenditure of nongraded walking to calculate the ARTEwalk index. Between-group differences were not detected for AEE or PAL. However, the ARTEwalk index revealed that participants with less adiposity were more physically active (258 ± 149 vs. 198 ± 115 min·day−1; P = 0.046; g = 0.46). AEE and PAL did not correlate with cardiorespiratory fitness or biomarkers of cardiometabolic health. Cardiorespiratory fitness (r = 0.32), arterial elasticity (r = 0.24), total cholesterol/HDL-c ratio (r = −0.22), and body fat% (r = −0.24) were correlated with ARTEwalk. The ARTEwalk index may offer utility in detecting possible differences in physical activity volume among postmenopausal women and appears better associated with cardiometabolic biomarkers compared with AEE or PAL.
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    Cardiovascular-Related Outcomes in U.S. Adults Exposed to Lead
    (MDPI, 2018-04) Obeng-Gyasi, Emmanuel; Armijos, Rodrigo X.; Weigel, M. Margaret; Filippelli, Gabriel M.; Sayegh, M. Aaron; Earth Sciences, School of Science
    Cardiovascular-related clinical markers were evaluated in this cross-sectional study of United States adults (aged ≥ 20) exposed to lead via the National Health and Nutrition Examination Survey 2007–2008 and the 2009–2010 datasets. In four quartiles of exposure—0–2 μg/dL, 2–5 μg/dL, 5–10 μg/dL, and 10 μg/dL and over, clinical and anthropometric markers were evaluated—to examine how the markers manifested in the quartiles. Associations were determined via linear regression. Finally, clinical makers, and how they manifested between exposed and less-exposed occupations, were explored in addition to how duration of exposure altered these clinical markers. In regression analysis, Diastolic Blood Pressure (DBP) and high-density lipoprotein (HDL) cholesterol, were significantly associated with blood lead level (BLL). In the occupational analysis, Systolic Blood Pressure (SBP), DBP, C-reactive protein (CRP), triglycerides, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, showed differences between populations in the exposed and less-exposed occupations. Regarding Agriculture, Forestry & Fishing, the duration of exposure altered SBP, CRP, and LDL cholesterol. With mining, the duration of exposure altered SBP, DBP, triglycerides, and HDL cholesterol, whereas in construction, the duration in occupation altered SBP, triglycerides, and CRP. In conclusion, lead exposure has a profound effect on the cardiovascular system, with potentially adverse outcomes existing at all exposure levels.
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    The Effect of Active Gaming on Cardiovascular Outcomes
    (Office of the Vice Chancellor for Research, 2015-04-17) Aqeel, Dania; Ohlman, Tom; Mikesky, Alan E.; Naugle, Keith E.; Naugle, Kelly M.
    The U.S. society has become more accustomed to a sedentary lifestyle in the past few decades, partially due to increased time spent in front of a screen. Recently, active gaming, which allows an individual to be physically active during video game play, has been rising in popularity as a means of exercise. However, more research is needed to evaluate whether active gaming can produce cardiovascular responses that fall within the recommended ranges for daily physical activity given by the American College of Sports Medicine (40-60% of heart rate reserve (HRR)). The purpose of this study was to determine the effects of active gaming on cardiovascular outcomes and enjoyment. Nine young adults have been enrolled in this study and data collection is ongoing. Participants completed a training session and four experimental sessions. During each session, participants played one of the following active games at a self-selected intensity for 15 minutes. Heart rate (HR) and rate of perceived exertion (RPE) were measured during game play. Enjoyment was assessed on a 10-cm VAS after each game. Repeated measures ANOVAs were used to determine differences in HRR%, RPE, and enjoyment between games. The results showed that HRR% was greater for Kinect boxing (M=42.7±12.5) compared to all other games (p=.012; Kinect Tennis=35.4±10.7, Wii Boxing=31.8±14.5, Wii Tennis=35.4±10.8). RPE was significantly greater for Kinect Boxing (M=11.3±2.0) compared to Wii Tennis (M=9.67±1.5), p=.038. Enjoyment levels did not differ between games, p=.58 (Kinect Boxing=6.6±2.1, Kinect Tennis=7.1±1.2, Wii Boxing=5.9±0.8, Wii Tennis=6.9±0.9). In conclusion, the active games played at a self-selected intensity were perceived as moderately to highly enjoyable and were able to increase cardiovascular responses. However, the intensity of activity depended on the game. Participants achieved a moderate intensity level (i.e., 40-60% of HRR) while playing Kinect Boxing, but only achieved a light intensity level while playing the other games. Mentor: Kelly M. Naugle, Department of Kinesiology, School of Physical Education, Tourism, and Management, IUPUI
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    Society for cardiovascular magnetic resonance recommendations for training and competency of CMR technologists
    (Elsevier, 2022-01) Darty, Stephen; Jenista, Elizabeth; Kim, Raymond J.; Dyke, Christopher; Simonetti, Orlando P.; Radike, Monika; Bryant, Jen; Lawton, Chris Benny; Freitag, Nicole; Shah, Dipan J.; Bucciarelli-Ducci, Chiara; Raman, Subha; Plein, Sven; Elliott, Michael D.; Medicine, School of Medicine
    The Society for Cardiovascular Magnetic Resonance (SCMR) recommendations for training and competency of cardiovascular magnetic resonance (CMR) technologists document will define the knowledge, experiences and skills required for a technologist to be competent in CMR imaging. By providing a framework for CMR training and competency the overarching goal is to promote the performance of high-quality CMR and to foster the increased adoption of CMR into clinical care.