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Aging, Complementary Medicine, Health and Fitness, Mental Health, Neuroscience, Research

Mindfulness training may ease depression and improve sleep for both caregivers and patients

Mindfulness training may ease depression and improve sleep for both caregivers and patients

meditatingDepression and poor sleep often affect both dementia patients and their caregivers. Now new research shows that caregivers and patients who undergo mindfulness training together experience an improvement in mood, sleep and overall quality of life.

While past studies have shown that yoga and simple meditations can relieve caregivers’ stress, researchers at Northwestern University wanted to determine if patients and caregivers could be trained together.

In the small study (subscription required), pairs of patients and caregiver participated in an eight-week mindfulness program. Patients were diagnosed with dementia due to Alzheimer’s disease or mild cognitive impairment, often a precursor to dementia. Caregivers included spouses, adult children or other relatives. The training was designed specifically to meet the needs of  individuals with memory loss due to terminal neurodegenerative illness and their caregivers. Researchers evaluated participants within two weeks of starting the program and two weeks of completing it.  Lead author Ken Paller, PhD, explained the results in a release:

We saw lower depression scores and improved ratings on sleep quality and quality of life for both groups… After eight sessions of this training we observed a positive difference in their lives.

Mindfulness involves attentive awareness with acceptance for events in the present moment… You don’t have to be drawn into wishing things were different. Mindfulness training in this way takes advantage of people’s abilities rather than focusing on their difficulties

Since caregivers often have limited personal time, mindfulness programs that accommodate them as well as patients could be an effective approach to helping both groups regularly attend sessions, said researchers.

The findings were published Monday in the American Journal of Alzheimer’s Disease and Other Dementias.

Previously: Regularly practicing hatha yoga may improve brain function for older adults, Study suggests yoga may help caregivers of dementia patients manage stress and How mindfulness-based therapies can improve attention and health
Photo by Alex

Aging, Autoimmune Disease, Immunology, Infectious Disease, Research, Stanford News

Our aging immune systems are still in business, but increasingly thrown out of balance

Our aging immune systems are still in business, but increasingly thrown out of balance

business as usual

Stanford immunologist Jorg Goronzy, MD, told me a few years ago that a person’s immune response declines slowly but surely starting at around age 40. “While 90 percent of young adults respond to most vaccines, after age 60 that response rate is down to around 40-45 percent,” he said. “With some vaccines, it’s as low as 20 percent.”

A shaky vaccine response isn’t the only immune-system slip-up. With advancing age, we grow increasingly vulnerable to infection (whether or not we’ve been vaccinated), autoimmune disease (an immune attack on our own tissues) and cancer (when a once well-behaved cell metamorphoses into a ceaselessly dividing one).

A new study led by Goronzy and published in Proceedings of the National Academy of Sciences, suggests why that may come about. The culprit he and his colleagues have fingered turns out not to be the most likely suspect: the thymus.

This all-important organ’s job is to nurture an army of specialized  immune cells called T cells. (The “T” is for “Thymus.”) T cells are capable of recognizing and mounting an immune response to an unbelievably large number of different molecular shapes, including ones found only on invading pathogens or on our own cells when they morph into incipient tumor cells.

Exactly which feature a given T cell recognizes depends on the structure of a receptor molecule carried in abundance on that T cell’s surface.  Although each T cell sports just one receptor type, in the aggregate the number of different shapes T-cells recognize is gigantic, due to a high rate of reshuffling and mutation in the genes dictating their receptors’ makeup. (Stanford immunologist Mark Davis, PhD, perhaps more than any other single individual,  figured out in the early 1980s how this all works.)

T cells don’t live forever, and their generation from scratch completely depends on the thymus. Yet by our early teens the organ,  situated  in front of the lungs at the midpoint of our chest, starts shriveling up and replaced by (sigh – you knew this was coming)  fat tissue.

After the thymus melts away,  new T-cells come into being only when already-existing ones undergo cell division, for example to compensate for the attrition of their neighbors in one or another immune-system dormitory (such as bone marrow, spleen or a lymph node).

It’s been thought that the immune-system’s capacity to recognize and mount a response to pathogens (or incipient tumors) fades away because with age-related T-cell loss comes a corresponding erosion of diversity:  We just run out of T-cells with the appropriate receptors.

The new study found otherwise.  “Our study shows that the diversity of the human T-cell receptor repertoire is much higher than previously assumed, somewhere in the range of one billion different receptor types,” Goronzy says. “Any age-associated loss in diversity is trivial.” But the study also showed an increasing imbalance, with some subgroups of T cells (characterized by genetically identical  receptors)  hogging the show and other subgroups becoming vanishingly scarce.

The good news is that the players in an immune response are all still there, even in old age. How to restore that lost balance is the question.

Previously: How to amp up an aging immune response, Age-related drop in immune responsiveness may be reversible and Deja vu: Adults’ immune systems “remember” microscopic monsters they’ve never seen before
Photo by Lars Plougmann

Genetics, Medicine and Society, Pain, Research, Science, Stanford News

From plant to pill: Bioengineers aim to produce opium-based medicines without using poppies

From plant to pill: Bioengineers aim to produce opium-based medicines without using poppies

Basic RGBStanford bioengineer Christina Smolke, PhD, and her team have been on a decade-long mission to replicate how nature produces opium in poppies by genetically engineering the DNA of yeast and then further refining the process to manufacture modern day opioid drugs such as morphine, codeine and the well-known painkiller Vicodin.

Smolke outlined the methods in a report  (subscription required) published in this week’s edition of Nature Chemical Biology, which details the latest stages in the process of manufacturing opium-based medicines, from start to finish, in fermentation vats, similar to the process for brewing beer.

An article published today in the Stanford Report offers more details:

It takes about 17 separate chemical steps to make the opioid compounds used in pills. Some of these steps occur naturally in poppies and the remaining via synthetic chemical processes in factories. Smolke’s team wanted all the steps to happen inside yeast cells within a single vat, including using yeast to carry out chemical processes that poppies never evolved to perform – such as refining opiates like thebaine into more valuable semi-synthetic opioids like oxycodone.

So Smolke programmed her bioengineered yeast to perform these final industrial steps as well. To do this she endowed the yeast with genes from a bacterium that feeds on dead poppy stalks. Since she wanted to produce several different opioids, her team hacked the yeast genome in slightly different ways to produce each of the slightly different opioid formulations, such as oxycodone or hydrocodone.

“We are now very close to replicating the entire opioid production process in a way that eliminates the need to grow poppies, allowing us to reliably manufacture essential medicines while mitigating the potential for diversion to illegal use,” Smolke added.

While it could take several more years to refine these last steps in the lab, bioengineering opioids would eventually lead to less dependence on legal poppy farming, which has numerous restrictions and international dependencies from other countries. It would also provide a reliable supply and secure process for manufacturing important pain killing drugs.

Previously: Blocking addiction risks of morphine without reducing its pain-killing effects, Do opium and opioids increase mortality risk? and Patients’ genetics may play a role in determining side effects of commonly prescribed painkillers 
Photo by Kate Thodey and Stephanie Galanie

Public Health, Public Safety, Research, Technology

Mining Twitter to identify cases of foodborne illness

During this year’s Big Data in Biomedicine conference at Stanford, Taha Kass-Hout, MD, chief health informatics officer for the U.S. Food and Drug Administration, talked about the potential of social media to monitor food safety saying, “You are what you eat, and in this world, you are what you tweet.” Taking this concept into a real-world setting, officials at the Chicago Department of Public Health developed an algorithm to mine Chicago-based tweets for sentiments of food illnesses and, as a result, were able to investigate incidents of food poisoning that would have otherwise gone unnoticed. According to a recent article in Popular Science:

… in a recent project, the city of Chicago sought food poisoning cases by setting an algorithm to mine Chicago-area tweets for complaints. The Chicago Department of Public Health’s Twitter bot, plus a new online complaint form, helped the department identify 133 restaurants for inspections over a 10-month period. Twenty-one of those restaurants failed inspection and 33 passed with “critical or serious” violations. Not a bad haul.

Chicago is now working with the health departments of Boston and New York to see if its system could work in those cities, according to a report city researchers published with the U.S. Centers for Disease Control and Prevention. Plus, Twitter isn’t the only social media platform cities are looking to mine for public health violations. In May, New York City’s department of health reported on using an algorithm to spot Yelp reviews that point to food poisoning cases. New York’s Yelp project led the city to discover three restaurants that had multiple violations. All the Yelp cases the city inspected had otherwise gone unreported, New York officials wrote in their own CDC report.

The Chicago bot was pretty simple, as Twitter-reading computer programs go. It searched for tweets geo-located to Chicago and its surrounding suburbs that mentioned “food poisoning.” Human staff then read the tweets to determine if they were relevant. (Sounds fun.) Staff marked tweets as relevant or not relevant, to give the algorithm data to better learn what tweets to pull in the future. Then staff members responded to relevant tweets themselves.

Previously: Videos of Big Data in Biomedicine keynotes and panel discussions now available online, Discussing access and transparency of big data in government and Improving methods for tracking flu trends using Twitter

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Cancer, Parenting, Pediatrics, Public Health, Research

Study shows number of American teens using sunscreen is declining

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Despite an increase in cases of melanoma, the most dangerous type of skin cancer, growing percentage of high school students get a failing grade when it comes to using sunscreen. HealthDay reports:

The number of U.S. teens using sunscreen dropped nearly 12 percent in the last decade, a new report shows.

During that same time period, the number of teens using indoor tanning beds barely decreased. Both indoor tanning and failure to use sunscreen increase the risk of skin cancers, including deadly melanomas, the researchers noted.

“Unfortunately, we found a decrease in the overall percentage of teens who reported wearing sunscreen, from 67.7 percent in 2001 to 56.1 percent in 2011,” said lead researcher Corey Basch, an associate professor in the department of public health at William Paterson University in Wayne, N.J.

“Using sun-protective behaviors like applying sunscreen and avoiding intentional exposure to tanning devices will be key [to lowering cancer risk],” she added.

Use of indoor tanning devices by white girls decreased only slightly, from 37 percent in 2009 to 29 percent in 2011, she said.

Study authors say more research is need to understand why teens aren’t following national guidelines regarding sun protection.

Previously: Melanoma rates exceed rates of lung cancer in some areas, Beat the heat – and protect your skin from the sun, Working to protect athletes from sun dangers and Stanford study: Young men more likely to succumb to melanoma
Photo by Alex Liivet

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Obesity, Parenting, Pediatrics, Research, Sleep

Study shows poor sleep habits as a teenager can “stack the deck against you for obesity later in life”

Study shows poor sleep habits as a teenager can "stack the deck against you for obesity later in life"

11386276_c148dfd9bd_zNew research examining the effect of sleeplessness on weight gain in teenagers over time offers strong evidence that inadequate sleep may increase the risk of obesity.

In the study, researchers at Columbia University and the University of North Carolina pored over health information from the the National Longitudinal Study of Adolescent Health on more than 10,000 Americans ages 16 and 21. In addition, details about individuals’ height, weight and sleep habits were collected during home visits in 1995 and 2001.  According to a release, results showed:

Nearly one-fifth of the 16-year-olds reported getting less than six hours of sleep. This group was 20 percent more likely to be obese by age 21, compared to their peers who got more than eight hours of sleep. While lack of physical activity and time spent watching television contributed to obesity, they did not account for the relationship between sleeplessness and obesity.

“Lack of sleep in your teenage years can stack the deck against you for obesity later in life,” says [Columbia researcher Shakira Suglia, ScD]. “Once you’re an obese adult, it is much harder to lose weight and keep it off. And the longer you are obese, the greater your risk for health problems like heart disease, diabetes, and cancer.”

“The message for parents is to make sure their teenagers get more than eight hours a night,” adds Suglia. “A good night’s sleep does more than help them stay alert in school. It helps them grow into healthy adults.”

Previously: Want teens to eat healthy? Make sure they get a good night’s sleepProlonged fatigue and mood disorders among teensMore evidence linking sleep deprivation and obesityStudy shows link between lack of sleep and obesity in teen boys and Study shows lack of sleep during adolescence may have “lasting consequences” on the brain
Photo by Adrian Sampson

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Health and Fitness, Neuroscience, Research

Regularly practicing hatha yoga may improve brain function for older adults

77878_webPast studies have suggested that practicing yoga can help those suffering from insomnia rest easier and boost the immune system. Now new research shows that regularly participating in hatha yoga, which emphasizes physical postures and breath control, may improve older adults’ cognitive function.

In a study (subscription required) involving more than 100 adults ages 55 to 79, researchers assigned roughly half of the individuals to attend hatha yoga classes three times a week for eight weeks while the others participated in sessions in which they engaged in stretching and toning exercises. The Huffington Post reports:

At the end of eight weeks, the group that did yoga three times a week performed better on cognitive tests than it had before the start of yoga classes.

The group that did stretching and toning displayed no significant change in cognitive performance over time. In addition, researchers say the differences seen between the groups were not the result of age, gender, social status or other similar factors.



Edward McAuley
, PhD, who co-led the study, noted that participants in the yoga group displayed significant improvements in working memory capacity. “They were also able to perform the task at hand quickly and accurately, without getting distracted,” he said in a press release. “These mental functions are relevant to our everyday functioning, as we multitask and plan our day-to-day activities.”

Previously: Stanford researchers use yoga to help underserved youth manage stress and gain focus, Third down and ommm: How an NFL team uses yoga and other tools to enhance players’ well-being, Yoga classes may boost high-school students’ mental well-being and Study shows yoga may improve mood, reduce anxiety
Photo by Neha Gothe

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Bioengineering, Cardiovascular Medicine, Neuroscience, Research, Stanford News, Stroke

Targeted stimulation of specific brain cells boosts stroke recovery in mice

big blue brainThere are 525,949 minutes in a year. And every year, there are about 800,000 strokes in the United States – so, one stroke every 40 seconds. Aside from the infusion, within three or four hours of the stroke, of a costly biological substance called tissue plasminogen activator (whose benefit is less-than-perfectly established), no drugs have been shown to be effective in treating America’s largest single cause of neurologic disability and the world’s second-leading cause of death. (Even the workhorse post-stroke treatment, physical therapy, is far from a panacea.)

But a new study, led by Stanford neurosurgery pioneer Gary Steinberg and published in Proceedings of the National Academy of Sciences, may presage a better way to boost stroke recovery. In the study, Steinberg and his colleagues used a cutting-edge technology to directly stimulate movement-associated areas of the brains of mice that had suffered strokes.

Known as optogenetics – whose champion, Stanford psychiatrist and bioengineer Karl Deisseroth, co-authored the study – the light-driven method lets investigators pinpoint a specific set of nerve cells and stimulate only those cells. In contrast, the electrode-based brain stimulation devices now increasingly used for relieving symptoms of Parkinson’s disease, epilepsy and chronic pain also stimulate the cells’ near neighbors.

“We wanted to find out whether activating these nerve cells alone can contribute to recovery,” Steinberg told me.

As I wrote in a news release  about the study:

By several behavioral … and biochemical measures, the answer two weeks later was a strong yes. On one test of motor coordination, balance and muscular strength, the mice had to walk the length of a horizontal beam rotating on its axis, like a rotisserie spit. Stroke-impaired mice [in which the relevant brain region] was optogenetically stimulated did significantly better in how far they could walk along the beam without falling off and in the speed of their transit, compared with their unstimulated counterparts. The same treatment, applied to mice that had not suffered a stroke but whose brains had been … stimulated just as stroke-affected mice’s brains were, had no effect on either the distance they travelled along the rotating beam before falling off or how fast they walked. This suggests it was stimulation-induced repair of stroke damage, not the stimulation itself, yielding the improved motor ability.

Moreover, levels of some important natural substances called growth factors increased in a number of brain areas in  optogenetically stimulated but not unstimulated post-stroke mice. These factors are key to a number of nerve-cell repair processes. Interestingly, some of the increases occurred not only where stimulation took place but in equivalent areas on the opposite side of the brain, consistent with the idea that when we lose function on one side of the brain, the unaffected hemisphere can step in to help restore some of that lost function.

Translating these findings into human trials will mean not just brain surgery, but also gene therapy in order to introduce a critical light-sensitive protein into the targeted brain cells. Steinberg notes, though, that trials of gene therapy for other neurological disorders have already been conducted.

Previously: Brain sponge: Stroke treatment may extend time to prevent brain damage, BE FAST: Learn to recognize the signs of stroke and Light-switch seizure control? In a bright new study, researchers show how
Photo by Shutterstock.com

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Neuroscience, Pediatrics, Research, Stanford News

Kids’ brains reorganize as they learn new things, study shows

Kids' brains reorganize as they learn new things, study shows

arithmeticWhy do some children pick up on arithmetic much more easily than others? New Stanford findings from the first longitudinal brain-scanning study of kids solving math problems are shedding light on this question. The work gives interesting insight into how a child’s brain builds itself while also absorbing, storing and using new information. It turns out that the hippocampus, already known as a memory center, plays a key role in this construction project.

Published this week in Nature Neuroscience, the research focuses on what’s happening in the brain as children shift from counting on their fingers to the more efficient strategy of pulling math facts directly from memory. To conduct the study, the research team collected two sets of magnetic resonance imaging scans, about a year apart, on a group of grade-schoolers. From our press release:

“We wanted to understand how children acquire new knowledge, and determine why some children learn to retrieve facts from memory better than others,” said Vinod Menon, PhD, the Rachel L. and Walter F. Nichols, MD, professor of psychiatry and behavioral sciences at Stanford and the senior author of the study. “This work provides insight into the dynamic changes that occur over the course of cognitive development in each child.”

The study also adds to prior research into the differences between how children’s and adults’ brains solve math problems. Children use certain brain regions, including the hippocampus and the prefrontal cortex, very differently from adults when the two groups are solving the same types of math problems, the study showed.

“It was surprising to us that the hippocampal and prefrontal contributions to memory-based problem-solving during childhood don’t look anything like what we would have expected for the adult brain,” said postdoctoral scholar Shaozheng Qin, PhD, who is the paper’s lead author.

The study found that as children aged from an average of 8.2 to 9.4 years, they counted less and pulled facts from memory more when solving math problems. Over the same period, the hippocampus became more active and forged new connections with other parts of the brain, particularly several regions of the neocortex. But comparison groups of adolescents and adults were found on brain scans not to be making much use of the hippocampus when solving math problems. In other words, Menon told me, “The hippocampus is providing a scaffold for learning and consolidating facts into long-term memory in children.” And the stronger the scaffold of connections in an individual child, the more readily he or she pulled math facts from memory.

Now that the scientists have a baseline understanding of how this brain-building process normally works, they hope to run similar brain-scanning tests on children with math learning disabilities, with the aim of understanding what goes awry in the brains of children who really struggle with math.

Previously: Unusual brain organization found in autistic kids who best peers at math, Peering into the brain to predict kids’ responses to math tutoring and New research tracks “math anxiety” in the brain
Photo by Yannis

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Behavioral Science, Neuroscience, Research

Why memories of mistakes may speed up learning

Why memories of mistakes may speed up learning

mistake_learningRemember when you burnt the crab cakes on one side while testing a new recipe for a dinner party and had to compensate by generously dressing them with a creamy sauce? What about the time you were introduced to a friend’s new girlfriend, whose name was somewhat similar to the last one, and you called her the wrong name? Or that accidental trip down a one-way street while in an unfamiliar city? Chances are you didn’t make these mistakes twice.

Now findings (subscription required) published today in Science Express may explain how memories of past errors speed learning of subsequent similar tasks. As explained in a release, scientists have known that when performing a task, the brain records small differences between expectation and reality and uses this information to improve next time. For example, if you’re learning how to drive a car the first time you may press down on the accelerator harder than necessary when shifting from the break pedal. Your brain notes this and next time you press down with a lighter touch. The scientific term for this is “prediction errors,” and the process of learning is largely unconscious. What’s surprising about this latest study is “that not only do such errors train the brain to better perform a specific task, but they also teach it how to learn faster from errors, even when those errors are encountered in a completely different task. In this way, the brain can generalize from one task to another by keeping a memory of the errors.”

To arrive at this conclusion, researchers used a  simple set of experiments where volunteers were placed in front of joystick that was hidden under a screen. More from the release:

Volunteers couldn’t see the joystick, but it was represented on the screen as a blue dot. A target was represented by a red dot, and as volunteers moved the joystick toward it, the blue dot could be programmed to move slightly off-kilter from where they pointed it, creating an error. Participants then adjusted their movement to compensate for the off-kilter movement and, after a few more trials, smoothly guided the joystick to its target. In the study, the movement of the blue dot was rotated to the left or the right by larger or smaller amounts until it was a full 30 degrees off from the joystick’s movement. The research team found that volunteers responded more quickly to smaller errors that pushed them consistently in one direction and less to larger errors and those that went in the opposite direction of other feedback.

Daofen Chen, PhD, a program director at the National Institute of Neurological Disorders and Stroke, commented on the significance of the findings saying, “This study represents a significant step toward understanding how we learn a motor skill … The results may improve movement rehabilitation strategies for the many who have suffered strokes and other neuromotor injuries.”

Previously: Depression, lifestyle choices shown to adversely affect memory across age groups, Newly identified protein helps explain how exercise boosts brain health and Exercise may protect aging brain from memory loss following infection
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From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

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