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Social and Behavioral Sciences Commons

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Articles 1 - 3 of 3

Full-Text Articles in Social and Behavioral Sciences

Progenitor Cells And Age: Can We Fight Aging With Exercise?, Sarah Witkowski, James M. Hagberg Mar 2007

Progenitor Cells And Age: Can We Fight Aging With Exercise?, Sarah Witkowski, James M. Hagberg

Exercise and Sport Studies: Faculty Publications

No abstract provided.


Transcranial Doppler Estimation Of Cerebral Blood Flow And Cerebrovascular Conductance During Modified Rebreathing, Jurgen A.H.R. Claassen, Rong Zhang, Qi Fu, Sarah Witkowski, Benjamin D. Levine Mar 2007

Transcranial Doppler Estimation Of Cerebral Blood Flow And Cerebrovascular Conductance During Modified Rebreathing, Jurgen A.H.R. Claassen, Rong Zhang, Qi Fu, Sarah Witkowski, Benjamin D. Levine

Exercise and Sport Studies: Faculty Publications

Clinical transcranial Doppler assessment of cerebral vasomotor reactivity (CVMR) uses linear regression of cerebral blood flow velocity (CBFV) vs. end-tidal CO2 (PETCO2) under steady-state conditions. However, the cerebral blood flow (CBF)-PETCO2 relationship is nonlinear, even for moderate changes in CO2. Moreover, CBF is increased by increases in arterial blood pressure (ABP) during hypercapnia. We used a modified rebreathing protocol to estimate CVMR during transient breath-by-breath changes in CBFV and PETCO2. Ten healthy subjects (6 men) performed 15 s of hyperventilation followed by 5 min of rebreathing, with supplemental O2 to maintain arterial oxygen saturation constant. To minimize effects of changes …


Cerebral Hemodynamics After Short- And Long-Term Reduction In Blood Pressure In Mild And Moderate Hypertension, Rong Zhanf, Sarah Witkowski, Qi Fu, Jurgen A.H.R. Claassen, Benjamin D. Levine Jan 2007

Cerebral Hemodynamics After Short- And Long-Term Reduction In Blood Pressure In Mild And Moderate Hypertension, Rong Zhanf, Sarah Witkowski, Qi Fu, Jurgen A.H.R. Claassen, Benjamin D. Levine

Exercise and Sport Studies: Faculty Publications

This study tested the hypothesis that acute reduction in blood pressure (BP) at the initial stage of antihypertensive therapy compromises brain perfusion and dynamic cerebral autoregulation in patients with hypertension. Cerebral blood flow velocity and BP were measured in patients with mild and moderate hypertension and in healthy volunteers at baseline upon reduction of BP within 1 to 2 weeks of administration of losartan/hydrochlorothiazide and after 3 to 4 months of treatment. The transfer function between beat-to-beat changes in BP and cerebral blood flow velocity was estimated to assess dynamic autoregulation. After 1 to 2 weeks of treatment, BP was …