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The NASA Light-Emitting Diode Medical Program -
Progress in Space Flight and Terrestrial Applications
Abstract. This work is supported and managed through
the NASA Marshall Space Flight Center - SBIR Program. Studies on
cells exposed to microgravity and hypergravity indicate that human
cells need gravity to stimulate cell growth. As the gravitational
force increases or decreases, the cell function responds in a linear
fashion. This poses significant health risks for astronauts in long
term space flight. LED-technology developed for NASA plant grown
experiments in space shows promise for delivering light deep into
tissues of the body to promote wound healing and human tissue growth.
This LED-technology is also biologically optimal for photodynamic
therapy of cancer.
LED-ENHANCEMENT OF CELL GROWTH
TThe application of light therapy with the use
of NASA LED's will significantly improve the medical care that is
available to astronauts on long-term space missions. NASA LED's
stimulate the basic energy processes in the mitochondria (energy
compartments) of each cell, particularly when near-infrared light
is used to activate the color sensitive chemicals (chromophores,
cytochrome systems) inside. Optimal LED wavelengths include 680,
730 and 880 nm. The depth of near-infrared light penetration
into human tissue has been measured spectroscopically (Chance, et
al 1988). Spectra taken from the wrist flexor muscles in the forearm
and muscles in the calf of the leg demonstrate that most of the
light photons at wavelengths between 630-800 nm travel 23 cm through
the surface tissue and muscle between input and exit at the photon
detector. Our laboratory has improved the healing of wounds in laboratory
animals by using NASA LED light and hyperbaric oxygen. Furthermore,
DNA synthesis in fibroblasts and muscle cells has been quintupled
using NASA LED light alone, in a single application combining 680,
730, and 880 nm each at 4 Joules per centimeter squared.
Muscle and bone atrophy are well documented in astronauts, and various
minor injuries occurring in space have been reported not to heal
until landing on Earth. Long term space flight, with its many inherent
risks, also raises the possibility of astronauts being injured performing
their required tasks. The fact that the normal healing process is
negatively affected by microgravity requires novel approaches to
improve wound healing and tissue growth in space. NASA LED arrays
have already flown on Space Shuttle missions for studies of plant
growth. The U.S. Food and Drug Administration (FDA) has approved
human trials. The use of light therapy with LED's is an approach
to help increase the rate of wound healing in the microgravity environment,
reducing the risk of treatable injuries becoming mission catastrophes.
Wounds heal less effectively in space than here on Earth. Improved
wound healing may have multiple applications which benefit civilian
medical care, military situations and long-term space flight. Laser
light and hyperbaric oxygen have been widely acclaimed to speed
wound healing in ischemic, hypoxic wounds. An excellent review of
recent human experience with near-infrared light therapy for wound
healing was published by Conlan, et al in 1996.
1998; Whelan, 1999; Yu, 1997). Some of these
activities include increased fibroblast proliferation, growth factor
syntheses, collagen production and angiogenesis.
Lasers, however, have some inherent characteristics, which make
their use in a clinical setting problematic, including limitations
in wavelengths and beam width. The combined wavelengths of light
optimal for wound healing cannot be efficiently produced, and
the size of wounds which may be treated by lasers is limited.
Light-emitting diodes (LED's) offer an effective alternative
to lasers. These diodes can be made to produce multiple wavelengths,
and can be arranged in large, flat arrays allowing treatment of
large wounds. Our experiments suggest potential for using LED
light therapy at 680, 730 and 880 nm simultaneously, alone and
in combination with hyperbaric oxygen therapy, both alone and
in combination, to accelerate the healing process in Space Station
Missions, where prolonged exposure to microgravity may otherwise
retard healing. NASA LED's have proven to stimulate wound healing
at near-infrared wavelengths of 680, 730 and 880 nm in laboratory
animals, and have been approved by the U.S. Food and Drug Administration
(FDA) for human trials. Furthermore, near-infrared LED light has
quintupled the growth of fibroblasts and muscle cells in tissue
culture. The NASA LED arrays are light enough and mobile enough
to have already flown on the Space Shuttle numerous times. LED
arrays may prove to be useful for improving wound healing and
treating problem wounds, as well as speeding the return of deconditioned
personnel to full duty performance. Potential benefits to NASA,
military, and civilian populations include treatment of serious
burns, crush injuries, non-healing fractures, muscle and bone
atrophy, traumatic ischemic wounds, radiation tissue damage, compromised
skin grafts, and tissue regeneration.
Harry T. Whelan, M.D.1a,2,3, John M Houle, B.S.1a,
Noel T. Whelan1a,3, Deborah L. Donohoe, A.S., L.A.T.G.1a,
Joan Cwiklinski, M.S.N., C.P.N.P.1a, Meic H. Schmidt, M.D.1c,
Lisa Gould, M.D., PhD.1b, David Larson, M.D.1b,
Glenn A. Meyer, M.D.1a, Vita Cevenini3, Helen Stinson, B.S.3
1a Departments of Neurology, 1bPlastic Surgery and 1cNeurosurgery,
Medical College of Wisconsin, Milwaukee, WI 53226, (414) 456-4090
2Naval Special Warfare Group TWO, Norfolk, VA 23521, (757) 462-7759
3NASA-Marshall Space Flight Center, AL 35812, (256) 544-2121
| Jerry BergMarshall Space Flight Center, Huntsville,
Ala. |
November 13, 2003 |
| RELEASE : 03-366 |
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NASA Light-Emitting Diode Technology Brings Relief In Clinical Trials
A nurse holds a strange-looking device, moving it
slowly toward a young patient's face. The note-card-sized device
is covered with glowing red lights, but as it comes closer, the
youngster shows no fear. He's hopeful this painless procedure using
an array of lights will help ease or prevent some of the pain and
discomfort associated with cancer treatment.
The youngster is participating in the second phase of human clinical
trials for this healing device. The first round of tests, by Medical
College of Wisconsin researchers at Children's Hospital of Wisconsin
in Milwaukee, was so encouraging doctors have expanded the trials
to several U.S. and foreign hospitals.
"We've already seen how using LEDs can improve a bone-marrow
transplant patient's quality of life," said Dr. Harry Whelan,
professor of neurology, pediatrics and hyperbaric medicine at the
Medical College of Wisconsin. "These trials will hopefully
help us take the next steps to provide this as a standard of care
for this ailment."
The light is produced by light emitting diodes, or LEDs. They are
used in hundreds of applications, from electronic clock displays
to jumbo TV screens.
LEDs provide light for plants grown on the Space Station as part
of commercial experiments sponsored by industry. Researchers discovered
the diodes also had many promising medical applications, prompting
NASA to fund this research as well, through its Marshall Space Flight
Center in Huntsville, Ala.
Biologists have found that cells exposed to near-infrared light
from LEDs, which is energy just outside the visible range, grow
150 to 200 percent faster than cells not stimulated by such light.
The light arrays increase energy inside cells that speed up the
healing process.
In the first stage of the study, use of the LEDs resulted in significant
relief to pediatric bone-marrow transplant patients suffering the
ravages of oral mucositis, a common side effect of chemotherapy
and radiation treatments, according to Dr. David Margolis, an associate
professor of pediatrics at the Medical College, working with Dr.
Whelan on the study at Children's Hospital.
Many times young bone-marrow transplant recipients contract this
condition, which produces ulcerations in the mouth and throat, severe
pain and in some cases, inflammation of the entire gastro-intestinal
tract. Chewing and swallowing become difficult, if not impossible,
and a child's overall health is affected because of reduced drinking
and eating.
"Our first study was very encouraging, and using the LED device
greatly reduced or prevented the mucositis problem, which is so
painful and devastating to these children," said Whelan. "But
we still need to learn more. We're conducting further clinical trials
with larger groups and expanded control groups, as required by the
U.S. Food and Drug Administration, before the device can be approved
and available for widespread use."
The treatment device was a 3-by-5-inch portable, flat array of
light-emitting diodes. It was held on the outside of a patient's
left cheek for just over a minute each day. The process was repeated
over the patient's right cheek, but with foil placed between the
LED array and the patient, to provide a sham treatment for comparison.
There was no treatment of the throat area, which provided the control
for the first study.
The researchers compared the percentage of patients with ulcerative
oral mucositis to historical epidemiological controls. Just 53 percent
of the treated patients in the bone-marrow transplant group developed
mucositis, considerably less than the usual rate of 70-90 percent.
Patients also reported pain reduction in their mouths when compared
to untreated pain seven days following bone marrow transplant.
The clinical trials are expected to take approximately three years
with a total of 80 patients. Participants currently include the
Medical College of Wisconsin in Milwaukee; Roswell Park Cancer Institute
in Buffalo, N.Y.; and Instituto de Oncologia Pediatrica, in Sao
Paulo, Brazil. Other domestic and international hospitals have asked
to join the multi-center study.
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