Virtual lung model allows scientists to measure pollutants' impact on healthy and diseased lungsRichland 27 October 2001 A virtual lung model developed at the US Department of Energy's (DOE) Pacific Northwest National Laboratory (PNNL) may help predict the impact of pollutants on respiratory systems and provide new insights into asthma, a condition afflicting 15 million American adults, as well as other pulmonary diseases. The computer model, called the virtual respiratory tract, provides an unprecedented, three-dimensional view of how pollutants enter, travel through, and collect in the entire respiratory system. PNNL's prototype system models the nose, larynx, and lungs of a rat. Efforts are underway to similarly model the respiratory systems of monkeys and humans.
Understanding biological impacts from pollution has become
more important as respiratory ailments have increased, as evidenced
by the nearly doubling of asthma sufferers since 1980. By learning
how particulates travel through the lungs, scientists can design
treatments which more precisely target drug delivery for pulmonary
diseases. They also can study how pollutants impact lungs of healthy
people compared with those who suffer from respiratory ailments.
"We designed a tool that will open up new possibilities for
understanding how our environment affects our bodies", stated
Rick Corley, principal investigator and a PNNL environmental
toxicologist. "The virtual respiratory tract is a major
accomplishment in modelling biological systems. It will be the
springboard for detailed modelling of the body's organs as a complete
system."
Using the virtual respiratory tract, PNNL scientists can analyse the
influence of various factors, such as the amount of pollutants or
length of exposure, on healthy versus diseased lungs by manipulating
the computer model. For example, they can begin to simulate how
gases, vapours, and particulates may act differently within lungs of
people suffering from cystic fibrosis, emphysema, and asthma.
The model is sufficiently detailed to track individual particles as
they move within the rat's respiratory system. In fact, according to
Rick Corley, the model's exceptional resolution could drive
development or use of new technologies to measure pollutants and
their potential impact in the respiratory tract at much greater
precision than is currently feasible.
PNNL scientists designed the highly detailed virtual respiratory
tract by combining the powerful capabilities of supercomputers, rapid
semi-automated computer modelling, and nuclear magnetic resonance
(NMR) imaging systems. The equipment is located in the William R.
Wiley Environmental Molecular Sciences Laboratory, a DOE user
facility located at PNNL.
Creation of PNNL's virtual respiratory tract began in the nuclear
magnetic resonance spectrometre facility, which contains instruments
capable of producing magnetic resonance images similar to those used
in diagnostic medicine but characterised by much higher spatial
resolution. With the NMR technology, laboratory scientists captured
images of a rat's upper respiratory tract and lungs in unprecedented
detail. Then, a semi-automated software package called NWGrid
analysed the data, reconstructed it into a computer model and
integrated information to show how air flows carrying particles might
move inside the imaged respiratory tract during breathing.
"The grid programme allows us to translate raw NMR data into a
computer image very quickly", explained Harold Trease, PNNL
computational physicist. "We can go from data sets to a working
model in hours compared with weeks or months required by other
approaches. This increased speed will allow us to replicate the
studies many times over, which will give us greater precision, or to
broaden our studies and create a database of information on healthy
and diseased lungs."
The laboratory's Biomolecular Networks Initiative has supported
development of the virtual respiratory tract with about $400.000 over
two years. In the upcoming third year of research, scientists will
refine the model using data obtained with newly developed NMR imaging
techniques. They also will continue to collaborate with other
institutions nationwide, including the University of California in
Davis, which has conducted extensive research into asthma using
animal models, and the University of Washington's pulmonary biology
and bio-engineering programmes.
Please, click the following hyperlinks to obtain an idea of the
virtual respiratory tract project:
Leslie Versweyveld |
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