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Nutrition, Obesity, Research

A call to focus on the nutritional value of foods, rather than calorie counts

A call to focus on the nutritional value of foods, rather than calorie counts

10331709463_60f2188a69_zTo reduce obesity rates, cardiovascular risk and chronic diseases, ditch calorie counting and instead emphasize the nutritional content of foods. That’s the message from a group of British researchers in an editorial recently published in Open Heart.

Drawing on past scientific evidence, the authors argue that physicians, patients and society’s focus on low-calorie foods and diets has resulted in a sacrifice of good nutrition and failed to improve overall public health. According to a press release:

Daily consumption of a sugary drink (150 calories) is associated with a significantly increased risk of type 2 diabetes whereas daily consumption of a handful of nuts (30 g of walnuts, 15 g of almonds and 15 g hazelnuts) or four tablespoons of extra virgin olive oil (around 500 calories) is associated with a significantly reduced risk of heart attack and stroke.

It has been estimated that increasing nut consumption by two servings a week could stave off 90,000 deaths from cardiovascular disease in the US alone.

And the Action for Health in Diabetes trial shows that a low calorie diet on top of increased physical activity in patients with type 2 diabetes was not associated with a reduced risk of cardiovascular death despite significant weight loss and a monitoring period of 13.5 years, [the authors] point out.

“It is time to stop counting calories, and time to instead promote good nutrition and dietary changes that can rapidly and substantially reduce cardiovascular mortality. The evidence indeed supports the mantra that ‘food can be the most powerful form of medicine or the slowest form of poison’,” they write.

Previously: The trouble with the current calorie-counting system, Homemade: Community-based project teaches how to cook for health and Cooked food, calorie counts and food labels
Photo by Mariya Chorna

Aging, Global Health, In the News, Public Health, Research

As life expectancy rises worldwide, many are living longer with illness and disability

10812180384_18496a55f3_zGood news: Average life expectancy has continued to climb over the past two decades. The downside is that those extra years are often marked by chronic disease or disability, according to a new analysis published in the Lancet.

In the study, an international team of researchers examined fatal and nonfatal health loss across countries in an effort to help direct global-health policies to improve longevity and quality of life regardless of where a person lives.

HealthDay reports:

The analysis of data from 188 countries found that life expectancy for both sexes increased from just over 65 years in 1990 to 71.5 years in 2013, while healthy life expectancy rose from almost 57 years to slightly more than 62 years.

“The world has made great progress in health, but now the challenge is to invest in finding more effective ways of preventing or treating the major causes of illness and disability,” study author Theo Vos, a professor at the Institute for Health Metrics and Evaluation at the University of Washington in Seattle, said in a journal news release.

The rise in overall life expectancy is due to significant declines in illness and death caused by HIV/AIDS and malaria, the researchers said, along with major advances in combating infectious diseases, nutritional deficiencies, and mother and baby health problems.

Earlier this year, Laura Carstensen, PhD, director of the Stanford Center on Longevity, spoke at the Big Data in Biomedicine conference about modern society’s gains in life expectancy and called it an “unprecedented” time in history. During her presentation, she presented data on the current aging population and what aging might look like in the future.

Previously: A look at aging and longevity in this “unprecedented” time in history, “Are we there yet?” Exploring the promise, and the hype, of longevity research and Living loooooooonger: A conversation on longevity
Photo by jennie-o

Cancer, Research, Science, Stanford News, Stem Cells

A stem cell “kill switch” may make therapies safer, say Stanford researchers

A stem cell "kill switch" may make therapies safer, say Stanford researchers

3225255407_596aa5bdff_zStem cell biologist Hiromitsu Nakauchi, MD, PhD, and his colleagues published an interesting article today about how to use stem cell technology to boost our body’s own immune cells to fight cancer or chronic viral infections like HIV or Epstein Barr virus. Because there’s a possible cancer risk with the use of induced pluripotent stem cells, or iPS cells, in humans, he and his colleagues have devised an innovative way to specifically eliminate these cells within the body if they start to cause problems. Their research appears today in Stem Cell Reports.

As Nakauchi explained to me in an email:

The discovery of induced pluripotent stem cells created promising new avenues for therapies. However, the tumorigenic potential of undifferentiated iPSCs is a major safety concern that must be addressed before iPS cell-based therapies can be routinely used in the clinic.

The researchers studied a type of immune cell called a cytotoxic T cell. These cells recognize specific sequences, or antigens, on the surface of other cells. Some antigens indicate that the cell is infected with a virus; others are found on cells that have become cancerous. When a cytotoxic T cells sees these antigens, it moves in to kill the cell and remove the threat.

In order to ensure that our immune systems recognize the widest variety of antigens, developing T cells randomly shuffle their genes to create unique antigen receptors. Researchers have found that it’s possible to identify, and isolate, T cell populations that specifically recognize cancer cells. By growing those cells in the laboratory, and then injecting them back into a patient, clinicians can give a boost to the immune response that can help kill tumor cells. The technique is known as adoptive immunotherapy, and it’s shown promise in treating melanoma. However, these cytotoxic T cells can become exhausted as they fight the cancer and become less effective over time.

Recently researchers in Nakauchi’s lab showed that it’s possible to create induced pluripotent stem cells from cytotoxic T cells. These iPS cells are then induced to again become cytotoxic T cells. These rejuvenated T cells, or rejT cells, recognize the same antigen they did before their brief dip in the pluripotency pool, but they are far more sprightly than the cells from which they were derived – they can divide many more times and have longer telomeres (an indicator of youthfulness).

So far, so good. But, as Nakauchi mentioned above, iPS cells carry their own set of risks. Because they are by definition pluripotent (they can become any cell in the body), they can easily grow out of control. In fact, one way of proving a cell’s pluripotency is to inject it into an animal and see if it forms a type of tumor called a teratoma, which is made up of multiple cell types.

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Research, Science

Short and sweet: Research papers with succinct titles cited more often

Short and sweet: Research papers with succinct titles cited more often

As a burgeoning journalist, I was often coached to cut unnecessary words. College professors mandated that story ledes be short and snappy and never exceed 35 words in length. When I began working at a daily newspaper, my editors were constantly condensing paragraphs and reminding me that “it takes more skill to write short than it does to write long.”

So I was interested to read a Nature article about new research showing that scientific studies with shorter titles receive more citations. Boer Deng writes:

Adrian Letchford and his colleagues at the University of Warwick in Coventry, UK, analysed the titles of 140,000 of the most highly cited peer-reviewed papers published between 2007 and 2013 as listed on Scopus, a research-paper database. They compared the lengths of the papers’ titles with the number of times each paper was cited by other peer-reviewed papers— a statistic sometimes used as a crude measure of importance.

As they report in Royal Society Open Science, “journals which publish papers with shorter titles receive more citations per paper”.

The impetus for the current study came from a desire to pen better papers, says Letchford, and to see whether good writing is rewarded in research. “As scientists, we’re all cursed,” when it comes to writing, Letchford says, as researchers hone their specialised knowledge but often cannot explain themselves to readers outside their own field.

While some quoted in the article agreed that concise titles can offer advantages, including increasing appeal to outside audiences, John Ioannidis, MD, DSc, director of the Meta-Research Innovation Center at Stanford, questioned whether the findings were conclusive. He said, “I will continue to struggle finding appropriate titles for my papers without worrying about whether the title length may affect their citations.”

Previously: A conversation with John Ioannidis, “the superhero poised to save” medical research, Shake up research rewards to improve accuracy, says Stanford’s John Ioannidis and John Ioannidis discusses the popularity of his paper examining the reliability of scientific research

Genetics, Microbiology, Neuroscience, Research, Science, Stanford News

Quest for molecular cause of ALS points fingers at protein transport, say Stanford researchers

Quest for molecular cause of ALS points fingers at protein transport, say Stanford researchers

Amyotrophic lateral sclerosis, or ALS, is a progressive, fatal neurodegenerative disease made famous by Lou Gehrig, who was diagnosed with the disorder in 1939. Although it can be inherited among families, ALS more often occurs sporadically. Researchers have tried for years to identify genetic mutations associated with the disease, as well as the molecular underpinnings of the loss of functioning neurons that gradually leaves sufferers unable to move, speak or even breathe.

We hope that our research may one day lead to new potential therapies for these devastating, progressive conditions

Now Stanford geneticist Aaron Gitler, PhD, and postdoctoral scholar Ana Jovicic, PhD, have investigated how a recently identified mutation in a gene called C9orf72  may cause neurons to degenerate. In particular, a repeated sequence of six nucleotides in C9orf72 is associated with the development of ALS and another, similar disorder called frontotemporal dementia. They published their results today in Nature Neuroscience.

As Gitler explained in our release:

Healthy people have two to five repeats of this six-nucleotide pattern. But in some people, this region is expanded into hundreds or thousands of copies. This mutation is found in about 40 to 60 percent of ALS inherited within families and in about 10 percent of all ALS cases. This is by far the most common cause of ALS, so everyone has been trying to figure out how this expansion of the repeat contributes to the disease.

Gitler and Jovicic turned to a slightly unusual, but uncommonly useful, model organism to study the effect of this expanded repeat:

Previous research has shown that proteins made from the expanded section of nucleotides are toxic to fruit fly and mammalian cells and trigger neurodegeneration in animal models. However, it’s not been clear why. Gitler and Jovicic used a yeast-based system to understand what happens in these cells. Although yeast are a single-celled organism without nerves, Gitler has shown that, because they share many molecular pathways with more-complex organisms, they can be used to model some aspects of neuronal disease.

Using a variety of yeast-biology techniques, Jovicic was able to identify several genes that modulated the toxicity of the proteins. Many of those are known to be involved in some way in shepherding proteins in and out of a cell’s nucleus. They then created neurons from skin samples from people with and without the expanded repeat. Those with the expanded repeat, they found, often had a protein normally found in the nucleus hanging out instead in the cell’s cytoplasm.

Jovicic and Gitler’s findings are reinforced by those of two other research groups, who will publish their results in Nature tomorrow. Those groups used different model organisms, but came to the same conclusions, suggesting that the researchers may be close to cracking the molecular code for this devastating disease.

As Jovicic told me, “Neurodegenerative diseases are very complicated. They likely occur as a result of a defect or defects in basic biology, which is conserved among many distantly related species. We hope that our research may one day lead to new potential therapies for these devastating, progressive conditions.”

Previously: Stanford researchers provide insights into how human neurons control muscle movement, Researchers pinpoint genetic suspects in ALS and In Stanford/Gladstone study, yeast genetics further ALS research

In the News, Media, Medicine and Society, Public Health, Research, Science

Science for popular audiences is not just “adding to the noise”

Science for popular audiences is not just "adding to the noise"

4787885058_d174638233_zIf you’re reading this blog, chances are you’re a fan of popular science – i.e. scientific research made accessible to people who aren’t professional academics. Many academics, myself included, are also in favor of taking cutting-edge knowledge and sharing it broadly with the public.

But some scientists hesitate to share their work on forums like blogs and other social media. According to a recent SciLogs post, they worry that their knowledge might be wrong or incomplete, be misinterpreted, or just add more static to the internet’s noise. But, as the post lays out, those who think about such things are precisely those who should be publishing for broader audiences. Those who publish misinformation are not stopping to question the quality of the knowledge they broadcast; doubt and the recognition of ignorance are the hallmarks of true scientists. Adding even a small amount of high-quality research to the “science media ecosystem” helps.

Moreover, much of the public seems to have little trust in media, much trust in scientists, and is more receptive to information that acknowledges uncertainty. So bring on the science blogs!

Previously: Can science journals have beautiful prose?, The disturbing trend of science by press release, Science rapper “busts a move” to explain Nobel discovery, Science writer Deborah Blum on blogging: “There were so many smaller stories I wanted to tell” and Veteran blogger offers tips for starting a science blog
Photo by Robin Bray-Hurren

Aging, Podcasts, Public Health, Research, Stanford News

Stanford doctor on a mission to empower patients to talk about end-of-life issues

Stanford doctor on a mission to empower patients to talk about end-of-life issues

Each year, about 2.6 million people die in America. Although past research has shown that 7 out of 10 of us prefer to die at home, an estimated 70 percent of people die in the hospital, nursing home or long-term care facility. The disconnect between where people die and how they would prefer to spend their final days often happens because loved ones and doctors don’t know their end-of-life wishes. Only 20 to 30 percent of Americans have completed advanced directives.

It’s not easy to talk about death, and the terminology used in advanced directives can be confusing. I remember having to complete the form with my husband shortly before the birth of my first child. Despite having been in a relationship for 12 year, we had never discussed end-of-life issues. Imagining the scenarios that might lead to either of us being in a life-threatening situation was an extremely emotional exercise — especially as we awaited our son’s arrival. Did we want doctors to use every intervention possible to save our life? What if it meant sacrificing our quality of life? Did we want to be on life support? If so, how long?

We eventually turned to a friend, who was also a physician, to help us sort through the process. But we didn’t talk to our own primary care doctors and, to this day, our doctors have never asked us if we have an advance directive or about our end-of-life preferences. And this isn’t unusual. Recent research from VJ Periyakoil, MD, director of Stanford’s Palliative Care Education and Training, shows that most doctors struggle to talk with patients about what’s important to them in their final days, particularly if the patient’s ethnicity is different than their own.

In the latest 1:2:1 podcast, Periyakoil discusses her study findings and why it’s critical for all adults to complete an advance directive and initiate a conversation about their end-of-life wishes with their doctor and family. To get these conversations started and help patients navigate the emotionally-charged process, she launched the Stanford Letter Project, which provides templates in a range of languages asking patients simple questions about how they want to die.

Listen to the full podcast to learn more about the project and hear from Stanford Letter Project users about how they want to spend their final days.

Previously: How would you like to die? Tell your doctor in a letterIn honor of National Healthcare Decisions Day: A reminder for patients to address end-of-life issues, Study: Doctors would choose less aggressive end-of-life care for themselves and On a mission to transform end-of-life care

In the News, Media, Medical Education, Medicine and Society, Myths, Pregnancy, Research

Reality TV influences perspectives on pregnancy, study shows

Reality TV influences perspectives on pregnancy, study shows

272417047_806faa2243_zA new University of Cincinnati study on the influence that television programs have on pregnant women has found that most women are more affected by TV representations of childbirth than they think.

The study, funded by the NSF and conducted by Danielle Bessett, PhD, assistant professor of sociology, followed a diverse group of 64 women over the course of two years and investigated how they understood their television viewing practices related to pregnancy and birth. It found that class, as measured by education level, had the greatest influence on whether a woman acknowledged television as a significant source of pregnancy-related information. Highly educated women and those who worked outside the home were more likely to dismiss TV, while those with less education and who were unemployed or took care of children at home were more likely to report watching and learning from such shows as TLC’s “Baby Story” and “Maternity Ward” and Discovery Health’s “Birth Day.”

The particularly interesting finding is that TV portrayals affect women’s perceptions even when they don’t believe they have an influence. Bessett developed the term “cultural mythologies of pregnancy” to describe how TV, film, media, and word of mouth create expectations about “the way things are.” Most reality TV and fictionalized programming presents childbirth as more dramatic and full of medical interventions than the majority of births really are, and these images made a lasting impression on women.

As quoted in the press release, Bessett says, “Hearing women –– even women who said TV had no influence on them –– trace their expectations back to specific television episodes is one of the few ways that we can see the power of these mythologies.” Many women mentioned pregnancy representations they had seen long before they got pregnant.

Women who reported watching TV considered it part of a comprehensive childbirth education program and would often evaluate the programs’ reliability, while women who disavowed television saw it as entertainment or education for children, likely from a desire to be seen as valuing science and medical expertise.

“If we believe that television works most insidiously or effectively on people when they don’t realize that it has power, then we can actually argue that the more highly educated women who were the most likely to say that television really didn’t have any effect on them, may in the end actually be more subject to the power of television than were women who saw television as an opportunity to learn about birth and recognized TV’s influence,” hypothesizes Bessett.

“This research implies that many women underestimate or under-report the extent to which their expectations of pregnancy and birth are shaped by popular media,” concludes Bessett, suggesting that “scholars must not only focus on patients’ professed methods for seeking information, but also explore the unrecognized role that television plays in their lives.”

Previously: New reality shows shine harsh light on teen pregnancy and Study: TV dramas can influence birth control use
Photo by johnny_zebra

Aging, Research, Sleep

Having trouble sleeping? Research suggests spending more time outdoors

Having trouble sleeping? Research suggests spending more time outdoors

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Raise your hand if you didn’t sleep well last night. Findings published in the latest issue of Preventive Medicine show that increasing the amount of time you spend outdoors can improve sleep quality, particularly for men and people over the age of 65.

To better understand the relationship between insufficient sleep and outdoor space, researchers analyzed data from the Centers for Disease Control and Prevention’s Behavioral Risk Factor Surveillance System, which surveyed of more than 250,000 adults in the United States. This information was paired with data from a U.S. Department of Agriculture index that scores the country’s geographical areas for natural amenities, using hours of sunlight, an important factor in regulating a person’s circadian rhythm, and temperature. According to a release:

For men, the relationship between sleep and exposure to green space was much stronger than for women. And males and females 65 and over found nature to be a potent sleep aid, [Diana Grigsby-Toussaint, PhD, said.]

Grigsby-Toussaint noted that living near green landscapes is associated with higher levels of physical activity and that exercise in turn predicts beneficial sleep patterns.

The finding should be a boon for people who are having trouble sleeping as they age. “If there is a way for persons over 65 to spend time in nature, it would improve the quality of their sleep—and their quality of life—if they did so,” Grigsby-Toussaint said.

Researchers added that the findings underscored the importance of preserving nature and providing safe access to nature in urban development.

Previously: Green roofs are not just good for the environment, they boost productivity, study shows, Nature is good for you, right? and Out-of-office autoreply: Reaping the benefits of nature
Photo by Garry Knight

Medical Education, Microbiology, NIH, Public Health, Research, Videos

Investigating the human microbiome: “We’re only just beginning and there is so much more to explore”

Investigating the human microbiome: "We’re only just beginning and there is so much more to explore"

The more scientists learn about the body’s community of bacteria, the more they believe that the human microbiome plays an important role in our overall health. For example, research published earlier this week suggests that a specific pattern of high bacterial diversity in the vagina during pregnancy increases a woman’s risk of giving birth prematurely.

Despite these and other insightful findings, researchers have a long way to go to understand the composition of our internal microbial ecosystems. As Keisha Findley, a postdoctoral fellow at the National Human Genome Research Institute says in the above video, “We’re only just beginning and there is so much more to explore.”

Findley and colleagues are working to survey all of the fungi and bacteria living on healthy human skin and develop a baseline to determine how these microbial communities may influence skin conditions such as acne, athlete’s foot, skin ulcers and eczema. Watch the LabTV video above to learn more about her work.

Previously: Drugs for bugs: Industry seeks small molecules to target, tweak and tune up our gut microbes, A look at our disappearing microbes, Exploring the microbes that inhabit our bodies and Diverse microbes discovered in healthy lungs shed new light on cystic fibrosis
Via NIH Director’s Blog

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