The overall long-term goal of these studies is to understand the mechanisms by which pulmonary blood flow is controlled, and how that control contributes to gas exchange defects or optimization in health and disease. The specific goal is to use a novel MRI technique to quantify the spatial and temporal dynamics of blood flow in the normal human lung. Temporal heterogeneity in a number of physiological systems has been found to be a mark of healthy function, yet little is known about the temporal dynamics of blood flow in the human lung because the appropriate tools for measuring temporal heterogeneity have not been available. Recently we developed a noninvasive MRI technique that provides quantitative measurements of pulmonary blood flow with a spatial resolution of ~1 cm3 and a temporal resolution of ~10 s in the human lung permitting us to examine spatial-temporal heterogeneity in the human lung for the first time. Under the umbrella of this project, the Specifi Aims are designed to: 1) provide the fellow with training in the development of MRI techniques, with a goal of improving the temporal resolution in these studies;2) to develop innovative analysis techniques including aspects of non-linear systems to characterize the rich data sets resulting from our experimental techniques;and 3) examine the effects of altered inspired gas (O2 and CO2) in healthy subjects.

Public Health Relevance

The overall long-term goal of these studies is to understand the mechanisms by which pulmonary blood flow is controlled, and how that control contributes to gas exchange defects or optimization in health and disease. The importance of how pulmonary blood flow is controlled over time has never been studied in humans because of a lack of suitable tools. This project will study the temporal behavior of the distribution of pulmonary blood flow in humans for the first time laying the foundations for addressing future treatment of gas exchange defects.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Individual Predoctoral NRSA for M.D./Ph.D. Fellowships (ADAMHA) (F30)
Project #
5F30HL110755-02
Application #
8540173
Study Section
Special Emphasis Panel (ZRG1-F10A-S (20))
Program Officer
Colombini-Hatch, Sandra
Project Start
2012-09-01
Project End
2016-10-31
Budget Start
2013-09-01
Budget End
2014-08-31
Support Year
2
Fiscal Year
2013
Total Cost
$33,872
Indirect Cost
Name
University of California San Diego
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
804355790
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Sá, Rui Carlos; Asadi, Amran K; Theilmann, Rebecca J et al. (2014) Validating the distribution of specific ventilation in healthy humans measured using proton MR imaging. J Appl Physiol (1985) 116:1048-56
Asadi, Amran K; Cronin, Matthew V; Sá, Rui Carlos et al. (2013) Spatial-temporal dynamics of pulmonary blood flow in the healthy human lung in response to altered FI(O2). J Appl Physiol (1985) 114:107-18