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Public Health, Public Safety, Research, Sports

Study shows football helmet safety tests may not capture common cause of concussions

Study shows football helmet safety tests may not capture common cause of concussions

boy-164286_1280The football helmet is perhaps the most iconic piece of safety equipment there is, but we’re just now beginning to understand how helmets can — and should — protect the brain.

Blows that rotate the head are known to cause brain trauma, yet a new Stanford study (subscription required) has found that this kind of movement isn’t included in the tests currently used to evaluate a football helmet’s safety.

In the study, bioengineer David Camarillo, PhD, and his team investigated the types of head movements that cause concussions using computer models of the brain and data collected from Stanford football players wearing mouthguards instrumented with accelerometers (device that measures changes in velocity).

Using the computer model, they found that the brain’s movement increases when the head oscillates (moves back and forth) at 15-20 hertz and it completes a single oscillation in about 50 milliseconds. The field data from the accelerometers showed that the players typically experience head oscillations around 20 hertz.

When the research team compared these results to the scenarios used to test the safety of football helmets, they found a mismatch. The standard tests used to evaluate football helmet safety (acceleration tests and a test that drops a helmet-wearing dummy head from various heights) fail to include the rotational movements known to cause concussions; they also generate faster head oscillations (100 hertz); and measure head acceleration for only 15-36 milliseconds.

“The problem with having a model that doesn’t re-create what players actually experience in the field, is that you could optimize a helmet to perform well in the drop test that unintentionally performs poorly in the field,” said Fidel Hernandez, a doctoral candidate in mechanical engineering and one of the study’s lead authors, in a Stanford News story.

This is a big deal because roughly 70 percent of football players in the United States who rely on helmets to keep their head’s precious cargo safe are under the age of 14, and they receive, on average, a whopping 240 hits to the head each season.

Camarillo and his team hope their findings can be used to make more realistic and useful helmet tests.

Previously: Stanford bioengineers and clinicians team up to shed light on how concussions affect the brainForces at work in concussions more complicated than previously thought, new Stanford study revealsNow that’s using your head: Bike-helmet monitor alerts emergency contacts after a crash and Study shows concussion recovery may take longer for female, younger athletes
Image courtesy of Pixbay

Ask Stanford Med, Cancer, Genetics, Women's Health

Genetic testing and its role in women’s health and cancer screening

Genetic testing and its role in women's health and cancer screening

14342954637_3f8c3fde77_zYears ago, when I first learned that genetic testing could help screen for some cancers, such as breast, ovarian and bone, it seemed like a no-brainer to get this testing done. Now I know better; genetic testing is a helpful tool that can help you assess your risk for certain kinds of cancer, but it’s not recommended for everyone. Senior genetic counselor Kerry Kingham, a clinical assistant professor affiliated with the Cancer Genetics Clinic at Stanford, explains why this is the case in a recent Q&A with BeWell@Stanford.

Cancer can be “hereditary” or “sporadic” in nature, Kingham says. Hereditary cancers, such as the forms of breast cancer related to a mutation in the BRCA1 or BRCA2 genes, are associated with an inherited genetic mutation. In contrast, sporadic cancers arise independent of family history or other risk factors. Since genetics testing detects gene mutations, it can only be used to help screen for the mutations that may lead to forms of hereditary cancer.

Kingham elaborates on this point, when it makes sense to get genetic testing, and what the results may mean in the Q&A:

Twelve percent of women in the U.S. develop breast cancer; it is a common disease. Yet, only five to ten percent of these women will develop breast cancer because of a hereditary gene mutation.

The best step to take prior to deciding whether or not to proceed with genetic testing is to meet with a genetic counselor. Your doctor can provide a referral. The genetic counselor will take a three generation family history, discuss the testing that might be indicated for you or a family member, and explain the risks and benefits of the testing. They also discuss the potential outcomes of the testing: whether a mutation is found, a mutation is not found, or there are uncertain results. Even when a genetic test is negative, this may not mean that the individual or their family is not at risk for cancer.

At this point you may be wondering: Why bother with genetic testing if it’s only useful for hereditary cancers and a negative test result is no guarantee you’re risk-free? Kingham’s closing comment addresses this question nicely: “I would say that your genes don’t change – they are what they are, and knowing what is in our genes can often help us learn how to take better care of our health.”

Previously: Stanford researchers suss out cancer mutations in genome’s dark spotsAngelina Jolie Pitt’s New York Times essay praised by Stanford cancer expertNIH Director highlights Stanford research on breast cancer surgery choices and Researchers take a step towards understanding the genetics behind breast cancer
Photo by Paolo

Addiction, Emergency Medicine, Health Costs, Patient Care, Research

Questionnaire bests blood test at identifying patients with risky drinking behaviors

Questionnaire bests blood test at identifying patients with risky drinking behaviors

3144132736_9de39a590d_zAs many as half of the patients who visit the emergency room with traumatic injuries have alcohol in their bloodstream, and roughly 10 percent of these patients will return to the ER within a year. Today, many emergency rooms use blood alcohol tests to screen for patients with risky drinking behaviors. Yet a new study by researchers from Loyola University Medical Center suggests that a questionnaire may be a better way to identify at-risk patients.

In the study, researchers reviewed 222 records from patients 18 years of age and older that were admitted to Loyola University Medical Center’s level I trauma center between May 2013 and June 2014. Each of the patients in the study had a blood alcohol test and had answered the World Health Organization‘s 10-point questionnaire, called the Alcohol Use Disorders Identification Test (AUDIT). The research team compared the results of the blood test to that of the AUDIT test and found that the questionnaire was 20 percent more effective at identifying at-risk patients with dangerous drinking habits than the blood test.

As the researchers explain in their study, blood alcohol tests only provide “a snapshot of the patient’s recent drinking behaviors” by measuring of the amount of alcohol in the patient’s system at the instant the test is taken. In contrast, the questionnaire assesses the patient’s overall drinking behaviors by asking questions such as, how often they drink, how much they drink per day and if they have feelings of guilt or remorse after drinking.

These findings are significant because blood alcohol tests are often the only tool used to assess at-risk drinking behavior in ER patients. Their findings call this common practice into question and suggest that the AUDIT questionnaire may be a better way to identify, and ultimately prevent, potentially dangerous drinking behaviors.

Previously: Alcohol-use disorder can be inherited: But why?Could better alcohol screening during doctor visits reduce underage drinking? and How to make alcoholics in recovery feel welcome this holiday season
Via: Business Wire
Photo by: Julie °_°

In the News, Pediatrics, Public Health, Stanford News, Technology

Water-conscious hospital will debut in 2017 with expansion of Lucile Packard Children’s Hospital

Water-conscious hospital will debut in 2017 with expansion of Lucile Packard Children’s Hospital

hospital-expansion-exterior-stanford-childrensPlaces where people live and work tend to use a lot of water, and hospitals are no exception. According to the U.S. Environmental Protection Agency’s 2012 report on water use in public buildings, hospitals rank third in water use just behind senior care facilities and hotels.

Now, the Lucile Packard Children’s Hospital Stanford is working to buck this trend with a new expansion that will use the latest water and energy-saving techniques and tools. This 521,000 square foot addition, which will open in 2017, is predicted to use about 38 percent less water than a comparable hospital.

This sustainable approach to building design began long before the current drought situation in California made water conservation a top priority. “In 2008, when we started planning, we knew there was not enough rainfall to sustain even the most efficient hospital’s needs,” said Robin Guenther, lead designer of the expansion project, in a recent post on the Healthier, Happy Lives blog.

In the piece, Guenther and her team discuss some of the expansion’s energy saving features, including shade structures that reduce the building’s heat gain from the sun and moving the hospital’s data center to the roof where it can be cooled by a wind-powered ventilation system instead of by air conditioning. According to Guenther, these modifications will make the building’s thermal energy consumption about 60 percent less than the average hospital in Northern California.

“Sustainability is a guiding principle in everything we do,” Christopher G. Dawes, president and chief executive officer of the hospital, commented. “Everyone on our team shares in this commitment. It’s part of being a good neighbor and a member of the larger community, and ensuring we’re doing the best thing possible when it comes to preserving all of our environmental resources.”

Previously: Green roofs are not just good for the environment, they boost productivity, study shows and From the Stanford Medicine archives: A Q&A with actor Matt Damon on water and health
Image courtesy of Lucile Packard Children’s Hospital Stanford

Mental Health, Neuroscience

No time for a vacation? Take a break without leaving the office

No time for a vacation? Take a break without leaving the office

3863917188_4972c8fe11_zWhen you’re tired, overworked and stressed out, a good vacation can be just what the doctor ordered. The catch is that it’s not always easy to take a break when you need it most. If you’re nodding your head in agreement, check out this Harvard Business Review piece by Emma Seppälä, PhD, associate director of Stanford’s Center for Compassion and Altruism Research and Education.

As Seppälä explains in her piece, workers in the United States tend to have less vacation days than employees elsewhere. Moreover, many people find it hard to truly “unplug” when they finally do take a vacation because smartphones, Wi-Fi and other electronic devices are so readily available.

But, fewer vacation days and smartphones aren’t entirely to blame for the bloated work schedules that are ubiquitous here and elsewhere. As Seppälä explains, many salaried employees with ample vacation time sometimes feel they can’t take an extended holiday because vacations are not “productive” and being out of the office, and out of touch, can have negative repercussions.

“Unfortunately, the logic of both employees and employers is highly flawed,” Seppälä writes. “Both fail to realize that cutting into vacation time is actually detrimental to both organizations and their employees both in terms of financial and productivity costs.” One short-term solution that can help employees endure a long period of work is a “mini-break”— a vacation that’s compressed into a few hours and can be taken virtually anywhere. She elaborates:

Research by Sabine Sonnentag suggests that detaching from work is essential to enhanced productivity. Her work has shown that, while people who do not detach from work suffering from greater levels of exhaustion, those who do recover from job stress and are more likely to have higher engagement levels at work.

If you really can’t take a proper vacation, Adam Rifkin, successful Silicon Valley serial entrepreneur and founder of PandaWhale, suggests “taking a little downtime every day rather than pushing it off for some getaway week.” Sonnentag’s research also suggests that if you make an effort to completely disengage from work when the workday is over – by, for example, engaging in a hobby you enjoy, exercising, or taking a walk in nature – you will reap the benefits: you will feel less fatigued, more engaged at work, and more energized when you leave work.

Stopping to smell the roses can make a big difference in your overall well-being during periods of high work flow, but a mini-break is no substitute for the real thing. So, if you absolutely can’t take an extended vacation, make the most of the downtime you have. Just be sure you also find a way to take that long vacation you’ve been dreaming of.

Previously: Exposure to nature helps quash depression – so enjoy the great outdoors!Seven ways laughter can improve your well-beingWhat email does to your brain and How social connection can improve physical and mental health and Out-of-office autoreply: Reaping the benefits of nature
Photo by Joe Penniston

Events, Medicine and Literature, Medicine and Society, Patient Care, Sexual Health

Surgeon-author: “My intent is to let people know that the person next door could be intersex”

Surgeon-author: "My intent is to let people know that the person next door could be intersex"

None of the Above“How many of you know what intersex is?” surgeon and author Ilene Wong, MD, (who did her residency at Stanford and writes under the pen name I.W. Gregorio) asked an audience of medical students, doctors and community members at a recent panel discussion on the topic on Stanford’s campus.

Since we’d gathered at the event, which was sponsored by Stanford’s Medicine & the Muse Program and Pegasus Physician Writers, to listen to a book reading and discussion about intersex — a term that describes sex characteristics that are neither all female nor all male — you might think we were all well-informed about the topic. We were not, and our fidgety response to Gregorio’s opening question hinted at the problem we came to discuss: a widespread lack of knowledge in the medical, and general, community about intersex individuals.

As Gregorio and her fellow panelists, Jeanne Nollman, founder of the AIS-DSD Support Group, and Hillary Copp, MD, a pediatric urologist at the University of California, San Francisco, delved into the discussion topic – “Has the medical community failed the intersex community?” – we gained a better understanding of what it means to be intersex, why so little is known about it and what can be done to remedy this.

“I met my first intersex patient when I was pregnant with my first child,” Gregorio told us. “It made me think of what it means to be a woman and how your chromosomes determine so much.” At the time, medical students received little training on intersex, Gregorio said. “There’s still a huge gap in medical education on what intersex is. Too often intersex is distilled down to one line on the chalkboard or one question on an exam.”

Her experience inspired Gregorio to write None of the Above, a young adult book about an 18-year old girl who learns she is intersex. “Books help us think about and talk about difficult issues,” she explained. “My intent is to let people know that the person next door could be intersex.”

Intersex is more common than you may think, occurring in approximately one in every 2000 individuals. This means that a person is more likely to be intersex than they are to have cystic fibrosis – yet most people have heard of the latter condition.

So, why isn’t intersex more well known? Nollman and Copp offered some possible explanations. “Many people think [it’s] a dirty thing because it has the word ‘sex’ in it,” said Nollman. “They think it’s something shameful they can’t talk about.”

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Precision health, Research, Science, Transplants

Study: Treatment plans for kidney failure should consider cause and circumstances of disease

Study: Treatment plans for kidney failure should consider cause and circumstances of disease

3349943474_0e1bc4236b_zOne size seldom fits all, so it’s not surprising that one treatment regimen may not suit all patients with the same condition. Now, a new study of end-stage kidney failure shows the importance of taking factors like cause and circumstances of a patient’s disease into account when designing a treatment plan.

The study (subscription required) began when Stanford nephrology fellow Michelle O’Shaughnessy, MD, noted that patients with end-stage kidney-failure usually received the same generic treatment plan (dialysis or a kidney transplant), even though there are different causes of the disease and a patient’s condition can progress to kidney failure via many different routes.

As described in our press release, kidney disease is often caused by diabetes or hypertension, but it can also be caused by glomerular disease, a condition with many distinct subtypes. And:

[E]ach of the many glomerular disease subtypes is unique. In certain subtypes, the immune system attacks the kidneys; in others, it damages the blood vessels.

As a result, the various subtypes are treated using different methods before the kidneys begin to fail. The treatments may include steroids or stronger immunosuppressant medications. The resulting side effects can range from severe infections to diabetes to cancer.

For their work, O’Shaughnessy and her colleagues examined data collected from 84,301 patients with end-stage kidney disease caused by one of six major subtypes of glomerular disease. The results showed that the type of glomerular disease significantly affected how long the patient lived after they developed kidney failure; mortality ranged from 4 percent per year for one type of patient to 16 percent per year for another.

“It’s important to know why one kidney patient does well and another does poorly,” concluded O’Shaughnessy. “If physicians take into consideration what caused the kidneys to fail in the first place and what types of treatments patients received prior to kidney failure, it could possibly improve the patients’ quality of life or increase their life span.”

Previously: Keeping kidney failure patients out of the hospitalStudy shows higher Medicaid coverage leads to lower kidney failure ratesStudy shows higher rates of untreated kidney failure among older adults and Geography may determine kidney failure treatment level
Photo by scribbletaylor

NIH, Pregnancy, Research, Technology, Women's Health

Scientists create a placenta-on-a-chip to safely study process and pitfalls of pregnancy

Scientists create a placenta-on-a-chip to safely study process and pitfalls of pregnancy

2798127284_487b56b9cf_zThese days it seems that just about anything can be recreated on a microchip. But still, I did a double-take when I read about the new way that scientists are using technology to study pregnancy: They’ve created a “placenta-on-a-chip.”

A functioning placenta is critical for a healthy pregnancy because it regulates the flow of nutrients, oxygen and waste products between the mother and fetus. It also controls the fetus’ exposure to bacteria, viruses and other harmful substances. Researchers would like to learn more about how the placenta acts as a “crossing guard” and how it can regulate the body’s traffic so well. Yet, studying the placenta is hard to do because it’s highly variable, and tinkering with the placenta is risky for the fetus.

To overcome these challenges, an interdisciplinary team led by a University of Pennsylvania researcher created a two-chambered microchip that mimics the structure and function of the human placenta. The study was published online in the Journal of Maternal-Fetal and Neonatal Medicine and is reported on in this National Institutes of Health press release:

The device consists of a semi-permeable membrane between two tiny chambers, one filled with maternal cells derived from a delivered placenta and the other filled with fetal cells derived from an umbilical cord.

After designing the structure of the model, the researchers tested its function by evaluating the transfer of glucose (a substance made by the body when converting carbohydrates to energy) from the maternal compartment to the fetal compartment. The successful transfer of glucose in the device mirrored what occurs in the body.

As Roberto Romero, MD, chief of the perinatology research branch at the NIH’s National Institute of Child Health and Human Development, explains in the press release, this new technology could help researchers explore how the placenta works, and what happens when it fails, in ways that couldn’t be safely done before. This, the researchers say, could lead to more successful pregnancies.

Previously: NIH puts focus on the placenta, the “fascinating” and “least understood” organPlacenta: the video game, The placenta sacrifices itself to keep baby healthy in case of starvation, research showsThe placenta sacrifices itself to keep baby healthy in case of starvation, research shows and Program focuses on the treatment of placental disorders
Photo by Jack Fussell

Genetics, HIV/AIDS, Infectious Disease, Research, Stanford News

Study shows toothed whales have persisted millions of years without two common antiviral proteins

Study shows toothed whales have persisted millions of years without two common antiviral proteins

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Our ability to fend off the flu, HIV and other viruses is enhanced when proteins are produced by two “immune genes,” called MX1 and MX2. Other mammals also have these genes, but little is known about the role they play in the immune responses of these animals.

Now a study comparing the genomes and Mx genes of 60 mammal species has revealed a surprising finding: Every species in the study has functioning Mx1 and Mx2 genes except for dolphins, whales and orcas — species from a lineage of toothed whales that’s persisted for roughly 33 million years.

Gill Bejerano, PhD, a geneticist and developmental biologist, graduate student Benjamin Braun and their team wanted to know more about the status and function of Mx genes in non-human mammals. To do this, they examined and compared the part of the genome that contains the Mx genes in 60 different species including humans, cows, whales, dolphins and orcas.

I think this will open up very exciting research avenues, either to better protect the compromised whales, or to study their different viral defenses, and someday add them to our own arsenal.

The study, published this week in the Proceedings of National Sciences, showed that the Mx1 and Mx2 genes in the toothed whales (bottlenose dolphin, orca, Yangtze river dolphin and sperm whale) they tested were non-functional, and couldn’t produce the proteins that help fight viral infections. Bejerano explained the significance of this finding in our press release:

Given how important the Mx genes seem to be in fighting off disease in humans and other mammals, it’s striking to see a species lose them both and go about its business for millions of years.

To find out when in evolutionary history these genes became inactive the researchers compared the genomes of toothed whales to that of their closest ancestors, the baleen whales and hoofed mammals (ungulates). They found that the Mx genes function in baleen whales and hoofed mammals, but not in toothed whales. This means that some — perhaps all — toothed whales likely lost use of their Mx genes when this lineage split off from these ancestors about 33 million years ago (see Fig. 1).

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Behavioral Science, Events, Mental Health, Research, Videos

Stanford bioengineer uses his experience in Iraq to improve research of TBI and PTSD

Stanford bioengineer uses his experience in Iraq to improve research of TBI and PTSD

777423808In 2012, President Obama issued an Executive Order calling for better prevention, diagnosis and treatment of traumatic brain injury (TBI), post-traumatic stress disorder (PTSD) and other mental health conditions. Third-year doctoral student Russell Toll is one of many who is doing research in these areas, and he brings a unique perspective to his work: He’s both a bioengineer and an Army combat veteran.

In 2006, Toll was in charge of a combined tank and infantry platoon stationed in the Diyala River Valley, about an hour northeast from Baghdad, Iraq.

His unit deployed with 14 tanks; they came back with four. Within 15 months, 28 men in his batallion were killed and 132 were severely wounded. A third of his men earned the Purple Heart and his unit — the 1-12 CAV in the 1st Cavalry Division — earned the Valorous Unit Citation for extraordinary heroism.

Now, Toll is working with his graduate advisor, Amit Etkin, MD, PhD, an assistant professor in the Department of Psychiatry and Behavioral Sciences, to identify biomarkers associated with TBI and PTSD. Toll and Etkin will discuss their work at the West Coast preview of the film “Searching for Home: Coming Back from War” next Saturday, June 20, at Stanford’s Cubberley Auditorium.

Recently, I spoke with Toll to learn more about his experience in Iraq and his research.

How did your experience in Iraq inform your understanding of PTSD?

As a platoon leader, all of your thoughts and efforts are focused on keeping your unit safe and getting them home. Only after you get home and decompress do you realize how much [weight] you were carrying.

This is a common experience for many soldiers and people that have lived through a traumatic experience.

At what point in your military career did you become interested in bioengineering and research on TBI and PTSD?

The pivotal point was in 2009 when I visited Walter Reed [National Military Medical Center] to check in on my men. The care they received at the center was excellent, but some of the equipment and technology that was being used to diagnose and treat them seemed like it hadn’t changed since Vietnam.

When I returned to my hotel room at night, I found myself drawing up ways we could address this problem on the backs of napkins. I have a bachelors degree in systems engineering from West Point, and I decided to apply these skills as a graduate student in bioengineering.

What was it like to come to Stanford after spending 15 months in Iraq?

It was a stark transition from the Army to Stanford; I felt like I had just climbed off the tank and stepped straight into systems biology. It sounds funny, but in a way I was able to apply my military training to my graduate studies: I developed cooperative relationships with the “indigenous experts” so I could get help from my classmates. As evidenced by my friends, I’m good at surrounding myself with excellent people. Their tutoring, coaching and friendship — especially that of Shrivats Iyer — was a major reason I was able to make it this far.

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