John Rick Turner

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BACKGROUND It has previously been reported that the risk of ventricular arrhythmias is positively associated with ambient air pollution among patients with implantable cardioverter defibrillators (ICD) in Boston. AIMS To assess the association of community exposures to air pollution with ventricular arrhythmias in a cohort of ICD patients in metropolitan(More)
OBJECTIVE The purpose of the present study was to examine the potential interaction of ethnicity and SES on hemodynamic functioning at rest and during acute stress in normotensive adolescents with a family history of essential hypertension (EH). DESIGN The influences of ethnicity and socioeconomic status (SES) on cardiovascular function were evaluated at(More)
Investigation of the physiological correlates of psychological stress is of interest in relation to the putative impact of stress in the etiology of cardiovascular disease. Although the assessment of blood pressure and heart rate responses to psychological stress has been very informative, the addition of cardiac output measurement has added a further(More)
This study assessed gender differences in hemodynamic response patterns to behavioral stressors. In addition, the extent to which gender differences in cardiovascular reactivity were a function of the type of challenge was determined by employing tasks relying on stereotypically male areas of competence and a task relying on stereotypically female areas of(More)
A sample of 155 adults, age 18-49 years, including nearly equal subgroups of Black and White men and women, underwent evaluation of cardiovascular reactivity during 5 behavioral stressors. Among the men, overall blood pressure increases to tasks did not differ, but Blacks showed generally higher total peripheral resistance, whereas Whites showed greater(More)
OBJECTIVE Increased peripheral vasoconstriction (ie, total peripheral resistance, or TPR) has been implicated as playing an important role in the early development of essential hypertension. Some studies have demonstrated that Transcendental Meditation (TM) reduces high blood pressure, but the hemodynamic adjustments behind these blood pressure reductions(More)
Cardiovascular (CV) responsivity to and recovery from acute laboratory stressors, as derived from aggregate scores of CV functioning during and after postural change, video game challenge, social competence interview, and parent-child conflict discussion, were evaluated in 272 youths [mean age 13.5 +/- 2.6 years; 162 Blacks (77 males, 85 females), 110(More)
Cardiovascular responses were examined in a community sample of 128 subjects, comprised of 58 African American and 70 Caucasian American men and women. Subjects completed a battery of laboratory stressors including mental arithmetic, reaction time, a speech task, and the cold pressor test. In addition to systolic and diastolic blood pressures, the(More)
Cardiovascular responses to a competitive reaction-time task were monitored in 13 male subjects tested twice, 3 months apart. The temporal stability of blood pressure responses was in line with previous reports. However, in this study impedance cardiography permitted the investigation of the hemodynamic adjustments underlying the observed blood pressure(More)
The effect of high job strain (defined as high psychological demands plus low decision latitude at work) on blood pressure was determined in 129 healthy, nonhypertensive men (n = 65) and women (n = 64). Blood pressure measures included mean screening levels obtained in a clinical environment, mean ambulatory levels from one 8-hour workday, and the change in(More)