All breathing stories

Shore Fellows awarded valuable time

jake — Mon, 22 Oct 2007 13:33:21 -0400

N. Stuart Harris, an emergency physician at Massachusetts General Hospital, is also an active researcher doing groundbreaking research on hypoxia — a shortage of oxygen in the body.

Holding their breath for the breathless

70652986 — Mon, 26 Mar 2007 05:40:49 -0400

Two researchers at the Harvard School of Public Health (HSPH) got the idea of studying free divers to get information that would help them help the breathless to breathe better. "We hope that by studying these athletes, we can teach patients how to better cope and recover from episodes of breathlessness," says Andrew Binks.

Divers took a battery of tests to see why their breathing capacity is so different from that of other people. Both they and a comparison group of normals were hooked up to a mechanical ventilator that controlled how often and how deeply they breathed. This device prevented the divers from breathing faster and deeper than nondivers.

Study: Predatory dinosaurs had birdlike pulmonary system

50443248 — Fri, 20 Jul 2007 16:24:29 -0400

What could the fierce dinosaur Tyrannosaurus rex and a modern songbird such as the sparrow possibly have in common? Their pulmonary systems may have been more similar than scientists previously thought, according to new research from Harvard University and Ohio University.

Breathing restored after severe spinal-cord injury

70652986 — Mon, 26 Mar 2007 06:21:35 -0400

Keeping an animal functioning after a cervical spinal cord injury is nearly impossible. An American researcher developed the lower spinal cord rat model in the early 1900s. He found that lesioning the spinal cord of dogs between the eighth and tenth thoracic vertebrae produced hind-limb paralysis while letting animals stay self-sufficient. Yang Teng, director of spinal cord injury research at the West Roxbury Veterans Administration Medical Center (WRVA), first observed very transient breathing disorders while working on a rat version of the model in graduate school. One of his professors had shown that morphine's respiration-suppressing effects could be counteracted by the serotonin agonist 8-OH DPAT. Teng tried that drug and buspirone on the lower thoracic-injured rats. "It restored their breathing," he said. "But we knew that the underlying cause of loss of respiratory function in lower- thoracic injury is very different from cervical injury - different neuromuscular systems are involved."

Teng and Howard Choi, Harvard Medical School clinical fellow in physical medicine and rehabilitation, hypothesized that administering a contusion to half of the spinal cord would keep a cervically injured rat alive. Delivering such a lesion turned out to be difficult. The spinal cord is buried deep inside the body at the neck and thorax.

Choi began his experiments. In the earlier study, Teng delivered serotonin agonist one day after injury and restored breathing in the lower thoracic-injured rats for four hours. Choi delivered the drug four days after injury. Breathing was restored for the same length of time.

Breathing easier after spinal cord injuries

50443248 — Tue, 24 Jul 2007 12:21:29 -0400

njuries to the upper spinal cord can take a victim's breath away.
Most people don't know that breathing difficulties are the leading cause of disease and death after such injuries. Indeed, respiratory failure causes more deaths than limb paralysis does, and survivors often become dependent on ventilation machines.

For the first time, Harvard researchers successfully tested an inexpensive, readily available class of drugs that has restored normalcy to rats who suffered the same loss of breath as humans who receive spinal cord injuries in combat, falls, car wrecks, or by gun or knife. These drugs include buspirone, a tranquilizer used to ease anxiety in the elderly and to help people quit smoking.

Mystery of how lungs grow is solved

50443248 — Wed, 25 Jul 2007 10:01:34 -0400

The puzzle of how lungs grow has been solved. Scientists watching the process in mice embryos have found that budding and branching of new air sacs is driven by the mechanical stretching of individual cells.
What's more, they demonstrated that this growth can be adjusted by manipulating mechanical forces involved in the cells' skeleton, a framework of fine tubes and filaments that give the cell its shape and let it move.

Research in brief

50443248 — Wed, 25 Jul 2007 14:44:11 -0400

Optic nerve regenerated for first time, brings hope to glaucoma sufferers

For the first time, scientists have regenerated a damaged optic nerve - from the eye to the brain. This achievement, which occurred in laboratory mice and is described in the March 1 issue of the Journal of Cell Science, holds great promise for victims of diseases that destroy the optic nerve, and for sufferers of central nervous system injuries.

"For us, this is a dream becoming reality," says Dong Feng Chen, lead author of the study, assistant scientist at Schepens Eye Research Institute and an assistant professor of ophthalmology at Harvard Medical School. "This is the closest science has come to regenerating so many nerve fibers over a long distance to reach their targets and to repair a nerve previously considered irreparably damaged."

Full story, http://www.theschepens.org/df_chenrelease.htm

Mechanical tension helps shape lung development

Organ development in the embryo requires precise coordination and timing of cell growth in three-dimensional space to produce the correct anatomic form and shape. Researchers at Children's Hospital Boston, led by Donald Ingber, a senior researcher in the Vascular Biology Program, have demonstrated that the process of budding and branching in the developing lung is driven by mechanical forces generated within individual cells. They have also identified a possible biochemical target for intervention. These insights could lead to new ways to prevent, minimize, or even correct diseases and anomalies of the lungs, which are common in premature newborns.

Full story, http://www.childrenshospital.org/cfapps/CHdeptPagePressDisplay.cfm?Dept=... or visit http://labworks.hms.harvard.edu

Mechanism helps describe how airways respond to constriction

70652986 — Mon, 26 Mar 2007 05:35:52 -0400

In asthma, substances such as allergens irritate the airways and cause the smooth muscle cells around them to contract. With repeated attacks, lung tissues become damaged from cycles of inflammation and repair. Scar tissue forms, which forces the airways to change their shape, or remodel. The airway walls become abnormally thick, potentially interfering with breathing. Figuring out how to stop the thickening is a common goal among asthma experts. Now, Harvard School of Public Health Assistant Professor Daniel Tschumperlin and his colleagues have suggested a possible additional explanation for why the airways thicken, providing another research target. The work required the expertise of physicians, cell biologists, physiologists, engineers, physicists, and mathematicians, representing several institutions. Tschumperlin developed an in vitro cell culture model to mimic the conditions of the human lung when it constricts, and he detected the activation of a specific signal transduction pathway. To get a better idea of what was going on at the cell surface, Tschumperlin collaborated with groups headed by MIT biomedical engineers Peter So and Roger Kamm. The MIT scientists had unique, cutting-edge imaging tools that allowed them to reconstruct three-dimensional microscopic structures of living epithelial cells, or cells that line the airways. Another well-known MIT bioengineer, Douglas Lauffenburger, and his team worked on pinpointing the specifics of the biochemical pathway that had been detected. He developed a quantitative model to calculate the distribution of proteins among epithelial cells when the airway constricts.

Lung imaging method allows visualization of airways

70652986 — Mon, 26 Mar 2007 05:30:00 -0400

A new dynamic imaging technique described by Mitchell Albert, Harvard Medical School assistant professor of radiology at Brigham and Women's Hospital; Angela Tooker, MIT graduate student; Kwan Soo Hong, Harvard Medical School research fellow in radiology at BWH; and colleagues in the May 2003 Radiology promises to open new venues in research on lung diseases by creating clear MRI images of lung airways during breathing. In this technique, helium gas is polarized by bombardment with laser-polarized rubidium atoms and maintained in a magnetic field. One liter of the gas mixed with nitrogen is pumped into a bag and rushed to the next room to a patient lying inside an MRI scanner. As the patient breathes in, the MRI scanner records two images per second to create a movie during one breath. The technique has promise for advancing knowledge of an array of lung conditions. Traditional static images do not provide good visualization of the blockages and constrictions of the airways caused by diseases like asthma. "Researchers and physicians have never actually seen the bronchoconstriction and airway closure in images," Albert said, "so they had to guess what they look like."

Bottle-feeding before bed time may increase risk of childhood asthma

70652986 — Mon, 26 Mar 2007 05:26:20 -0400

Nearly one in 13 children in America has asthma. The National Institutes of Health reports that the prevalence of asthma around the world has doubled in the last 15 years, increasing 160 percent among pre-school age children. Asthma is the third leading cause of hospitalization among children under age 15 and accounts for more than 10 million missed school days annually. Researchers found that bottle feeding in the bed or crib before sleep time during the first year of life was a risk factor for asthma and recurrent wheezing at five years of age. It also appeared to be a risk factor for wheezing between the ages of one to five years. "For infants in a high-risk group, we found that when and how they are fed influence the onset of wheezing and asthma," said Juan Celedon of Brigham and Women's Hospital. "There is a significant relationship between the number of times children are bottle fed in the crib or bed prior to sleep time and the occurrence of wheezing during their first five years."

Breathing new life into asthma therapy

70652986 — Mon, 26 Mar 2007 05:13:21 -0400

Asthma attacks have lasting effects because the lungs' most delicate airways can become scarred. This makes future attacks all the worse. Researchers at Harvard Medical School have looked at what happens during asthma attacks, and believe that the damage to airways can be prevented or lessened by prescribing muscle relaxants in addition to anti-inflammatory steroids. Prescribing muscle relaxants is actually an old asthma therapy that was discarded two decades ago in favor of anti-inflammatory steroid treatments. The supplanting of one therapy by another has caused some physicians in the United States to resist the idea of combining the drugs, though such combined therapies — steroids and muscle relaxants in the same inhaler — are already used in Europe.

Mapping the brain's response to breathlessness

70652986 — Mon, 26 Mar 2007 05:06:41 -0400

In an experiment, healthy men were placed on ventilators, and their ability to take deep breaths was controlled. As their breathing was regulated, their brains were imaged using a PET camera. The images were then compared to scans taken prior to the experiment to see which areas, if any, were turned on when the body perceived it was not getting enough air. Through this study, Harvard School of Public Health researchers and colleagues from the Imperial College School of Medicine in London were able to identify the area of the brain that is activated during shortness of breath. "This kind of basic science underlies the understanding one needs to use breathlessness as a tool of diagnosis," said Robert Banzett, associate professor in the Department of Environmental Health and lead author of the study.