This radio program is a weekly series of episodes that provide insights into a broad range of biomedical science topics. We hope these episodes stimulate you to think, question and appreciate how science impacts you and your world.
Blast Brain Injury - Before Question
Pear or Apple - After Question
This Week's Episode
Blast Brain Injury
Imagine driving to the store and all of a sudden you can’t remember where you’re going. In fact you’re so disoriented you have to call someone to tell you how to get home. Sounds unbelievable yet it happens quite often to people with a traumatic brain injury.
Headaches, the inability to focus thoughts, becoming lost in familiar places and having trouble remembering things are just a few symptoms of traumatic brain injury. Unfortunately an increasing number of our soldiers returning from Iraq and Afghanistan are victims.
Their injury is obvious if there’s an open head wound but what about an injury you can’t see? We’re talking about a blast injury which can be caused by improvised explosive devices which we’re hearing about all too often. While the symptoms may be similar to head trauma from a car accident, the damage is different.
Motor vehicle accidents usually involve acceleration/deceleration motions. This means while a person’s head has stopped moving, the brain is still in motion and slams into the inside of the skull, causing contusions.
By comparison, the force from a blast sends waves of pressure through a person’s body.
The injury occurs when that energy is transmitted by the air or fluid surrounding certain organs in our body. They can include the ear, GI tract, spinal cord and of course the brain. Unlike a tumor or brain hemorrhage, a blast injury is often undetectable with imaging equipment because the injury occurs at the microscopic level.
The death of brain cells associated with learning or memory can happen months after the blast. In fact, blast injuries are sometimes called "silent injuries," because they go unnoticed.
Treatment for blast injury is still in its infancy. That’s why we need more research to understand it and design appropriate diagnostics and therapies to manage this "silent disease".
Left to Right: Yuan Li, Jeremy Cowart, YaPing Zeng, Kristen Kahrig, Evan Corning, Debbie Boone, Douglas S. DeWitt, Ph.D., Helen L. Hellmich, Ph.D., Stacy L. Sell, Ph.D., Bridget E. Hawkins, Joanne C. Cousins, Ph.D. Not pictured: Donald S. Prough, M.D., Donald J. Deyo, D.V.M., Maggie A. Parsley and Sheri Salsbury
"Some Light Stretching Limbers but Does Not Weaken Muscles" Most of us who were involved in athletics were taught the necessity of stretching before engaging in sports. However, there has been a long running debate whether short duration stretching reduces muscle strength and performance.
A new study reported recently involved participants who performed 0, 2, 4 and 8 minute passive stretching of the lower leg and ankle before measurements of muscle strength were taken immediately and at three time points thereafter. The results revealed no decline in muscle strength but did reveal improvements in the range and motion of their ankles.
It continues to be debated whether stretching before competition decreases performance. The present study was done on people that were active but non-athletes. It remains to be determined if stretching adversely affects the muscle performance of athletes. The duration of stretching beyond the 8 minutes of this study may also alter the results. The prevention of certain injuries by stretching may also influence decision about stretching prior to athletic events. >For more information…
"Consuming Fish Can Reduce Your Rick of Dementia by 26%" Eating fish that are rich in omega-3 fatty acids like tuna, salmon, anchovies, mackerel, herring and sardines will not make you more intelligent, but may lower your risk of dementia or stroke by 26%. However, fried fish does not confer this protection. People who consumed broiled or baked fish high in omega-3 fatty acids at least three times per week were 26% less likely to suffer silent brain infarcts that are small lesions in the brain associated with the loss of thinking skills, dementia or stroke than those who ate no fish. People eating fish once per week had a 13% reduced risk.
The study examined 3660 men and women at least 65 years old for the presence of these silent brain infarcts that are detectable only by an MRI scan of the brain. These infarcts can be detected in about 20% of otherwise healthy older individuals. Five years later, they tested about two thirds of the study participants again and questioned them about their diet. This revealed the protective effects of consuming fish. Not only were there fewer infarcts, there were also fewer changes to the white matter of their brains.
It should be noted however, that people who ate more fish also tended to have better diets in general including the consumption of higher amounts of fruits and vegetables. Therefore, the protective effects may be the result of a number of improvements to diet. The consumption of fish has also been linked to a decrease in the risk for Alzheimer’ disease. For more information…
"The Latest on the Salmonella Outbreak" The Salmonella outbreak that started with tomatoes as a possible source has slowed with the number of cases declining steadily. Determining the source of the outbreak continues to be complicate. Early evidence implicated tomatoes, but since then cases have been linked to the consumption of raw jalapeno and Serrano peppers as well as cilantro. The outbreak strain of Salmonella called saintpaul has twice been isolated from jalapenos and once from a Serrano pepper. The FDA lab isolated Salmonella sainpaul on a japapeno in McAllen, Texas and identified the distributor who has initiated a recall of the products which were grown in Mexico. An FDA lab also isolated Salmonella saintpaul from a Serrano pepper and from an agricultural water sample collected on a farm in Mexico which distributed its products through McAllen. Therefore both jalapeno and Serrano peppers appear to be sources of this food contamination. The Mexican Agricultural Department disputes that the peppers from the farm in Nuevo Leon had anything to do with the outbreak citing that their harvest was more than one month ago and that the water sample was taken from a rain water tank not used in production. Despite these protestations, the FDA suggests that people avoid the consumption of both these raw peppers and all uncooked foods that contain them. So despite these recent discoveries, the investigation is not over and there could be multiple sources of contamination which explains the complexity of the outbreak.
According to the CDC "Since April, 1348 persons infected with Salmonella Saintpaul with the same genetic fingerprint have been identified in 43 states, the District of Columbia, and Canada. These were identified because clinical laboratories in all states send Salmonella strains from ill persons to their State public health laboratory for characterization. The number of ill persons identified in each state is as follows: Alabama (5 persons), Arkansas (21), Arizona (57), California (12), Colorado (16), Connecticut (5), Florida (4), Georgia (40), Idaho (6), Illinois (117), Indiana (21), Iowa (2), Kansas (21), Kentucky (2), Louisiana (3), Maine (1), Maryland (38), Massachusetts (29), Michigan (26), Minnesota (21), Mississippi (2), Missouri (20), Montana (1), New Hampshire (5), Nevada (14), New Jersey (16), New Mexico (108), New York (39), North Carolina (28), Ohio (10), Oklahoma (38), Oregon (11), Pennsylvania (13), Rhode Island (3), South Carolina (2), Tennessee (10), Texas (508), Utah (2), Virginia (31), Vermont (2), Washington (18), West Virginia (1), Wisconsin (13), and the District of Columbia (1). Five ill persons are reported from Canada. Four appear to have been infected while traveling in the United States; the travel status of the fifth ill person is unknown." For more information…
"We May Now Know How Cranberries Prevent Urinary Tract Infections" The pathogenic forms of the E. coli bacterium that cause urinary tract infections attach to uroepithelial cells that line the urethra with hair-like appendages called fimbriae. When these bacteria are exposed to cranberry juice, their ability to attach and then colonize the cells lining the urinary tract is inhibited and their ability to cause infections is reduced. Now some researchers may have found out why. Cranberry juice affects the energy of binding between the molecules on the surface of the bacteria and those on the urinary tract cells. This alteration in the energy of binding between the bacteria and the cell surface prevents the E. coli from firmly attaching, and therefore they cannot establish an infection. Cranberry juice does not seem to prevent the bacteria that normally exist in the urinary tract from binding which also helps prevent those pathogenic bacteria from binding. Both regular and sugar free formulations of cranberry juice have this protective effect. However the inhibition of the binding of pathogenic E. coli to the urinary tract is only temporary, suggesting that a daily regime of drinking cranberry juice may be important. For more information…
Imagine driving to the store and all of a sudden you can’t remember where you’re going. In fact you’re so disoriented you have to call someone to tell you how to get home. Sounds unbelievable yet it happens quite often to people with a traumatic brain injury.