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Emergency Medicine, Events, Imaging, Medical Education, Stanford News

Ultrasound has its day – and evangelists galore

Ultrasound has its day -  and evangelists galore

ULTRAfestUltrasound isn’t just for babies anymore.

“We use it for everything from head to toe and skin and organs,” emergency medicine instructor Laleh Gharahbaghian, MD, recently told writer Sara Wykes for an Inside Stanford Medicine story. “It’s become an essential tool at  the bedside we apply to immediately rule out — or rule in — medical conditions.”

That’s why Gharahbaghian and her colleagues are hosting ULTRAfest, a full day of ultrasound instruction open to all medical students on Oct. 18. Last year, more than 300 students from across the western United States attended.

Ultrasound uses sound waves that are too high pitched for our ears to detect. The waves bounce off material in the body, providing a glimpse inside.

ULTRAfest2What’s so great about ‘Sound (as Gharahbaghian calls it on her Twitter page)? It’s relatively cheap — new scanners start at $90,000 — non-invasive and portable. Ultrasound has also moved beyond mere diagnostics. For example, Stanford radiologist Pejman Ghanouni, MD, PhD, uses ultrasound to treat uterine fibroids.

Although the technology isn’t new, researchers are finding new uses for ultrasound. As detailed in that Inside Stanford Medicine piece:

More recently, the use of ultrasound has crossed into another part of the anatomy long thought to be immune to its imaging prowess: the lungs. In the air-filled environment of the lungs, the sound waves that are the basis of ultrasound have nothing to ping against. However, in lungs where disease has produced fluids, ultrasound has proven more accurate than a chest X-ray and faster than CT scan to diagnose common lung conditions, including pulmonary edema, pneumonia and pleural effusions.

Other doctors and medical students, including U-fest volunteer William White aren’t shy about touting ultrasound’s benefits: “I just fell in love with the technology, picking up a probe and looking into the body in real time.”

Previously: New technology enabling men to make more confident decisions about prostate cancer treatment, Listening to the stethoscope’s vitals, Plane crash creates unexpected learning environment for medical students 
Photos by Teresa Roman-Micek

Imaging, Research, Science, Stanford News, Videos

Breaking the light barrier in medical microscopy: More on today’s Nobel-winning work

Breaking the light barrier in medical microscopy: More on today's Nobel-winning work

Earlier today, Stanford University’s W.E. Moerner, PhD, was one of three scientists to be awarded the Nobel Prize in Chemistry for work in super-resolution microscopy. Before this technology, the only way to look at structures inside cells was with electron microscopy. But that requires researchers to kill the tissue in order to prepare it for the microscope. Essentially, the objects being examined were frozen in place; scientists could make out cellular structures but couldn’t watch them in action.

Microscopes that use refracted light, or optical microscopes, can be used to observe living cells, but for decades, they were limited from going below 220 nanometers, a hard limit imposed by the wavelength of light. Eric Betzig, PhD, of Howard Hughes Medical Institute, and Stefan W. Hell, PhD, of the Max Planck Institute for Biophysical Chemistry in Germany shared the prize with Moerner for work that helped break that barrier. Now, researchers can peek inside cells as they are going about their business and observe real-time changes as they happen.

This morning, Moerner spoke to Stanford’s news office via Skype from Brazil about his work and how other researchers, including Lucy Shapiro, PhD, and Matt Scott, PhD, of Stanford’s School of Medicine are applying the new methods to medical research (see above video). Shapiro, a 10-year collaborator of Moerner’s, is examining structures inside bacteria and Scott is looking at subcellular signalling structures. (Shapiro provides comment on her work in a Stanford press release.)

“Because of this revolutionary work, scientists can now visualize the pathways of individual molecules inside living cells,” Francis Collins, MD, PhD, director of the National Institutes of Health, which funds some of Moerner’s work, said in a statement. “Researchers can see how molecules create synapses between nerve cells in the brain, and they can track proteins involved in Parkinson’s, Alzheimer’s and Huntington’s diseases.”

Below is a clip of Moerner describing what those studying Huntington’s disease have learned using the prize-winning microscopy technology.

Previously: For third year in row, a Stanford faculty member wins the Nobel Prize in Chemistry
Videos courtesy of Stanford University Communications

Imaging, Research, Science, Stanford News

Stanford researcher details structure of sugar transporter called SWEET

Stanford researcher details structure of sugar transporter called SWEET

SemiSWEETSugar fuels life. But to power our cells, sugar molecules have to slip in and out of cells. And in humans, the sugar sometimes needs to travel deep into tissues such as the intestines or the brain, far removed from the bloodstream.

Thanks to technological advances, scientists are still making new discoveries about these basic processes. And now, a team led by Stanford molecular biologist Liang Feng, PhD, and Carnegie Institution/Stanford biologist Wolf Frommer, PhD,  has unraveled the molecular structure and function of a type of protein that straddles cell membranes, allowing sugar to pass.

The name of the compound — oh, those scientists and their senses of humor — is SWEET, which stands for “Sugars Will Eventually be Exported Transporters.” SWEETs are found in all sorts of creatures, including humans, and plants; bacteria have semiSWEETs that are about half the size of a SWEET.

To determine the structure of these super-small proteins, Feng and his team used powerful X-ray equipment at the Argonne National Laboratory in Illinois and the Stanford Synchrotron Radiation Lightsource on campus. “Before our study, we had no idea what the protein looked like and how it could function,” Feng told me.

As described in a paper published earlier this month in Nature, Feng and his colleagues learned that SWEET actively changes shape to swallow sugar, unlike a fixed channel such as a train tunnel. SWEET swings open jaws like a crocodile, clamps them shut, then shoots the sugar into the cell interior.

SWEETs, and the two other types of sugar transporters found in humans, could play a prominent role in a variety of human diseases, including diabetes, although most research now has been done in plants. The project produced what Feng calls “snapshots” of SWEET transporting sugar. Next, he plans to develop a moving “video” of the protein.

“We need to understand the blueprint of this machinery,” Feng said. “What we learn could be used to improve crop yield or to design drugs that can help with sugar-related diseases such as diabetes.”

Becky Bach is a former park ranger who now spends her time writing about science or on her yoga mat. She is a science-writing intern in the Office of Communications and Public Affairs. 

Previously: Civilization and its dietary (dis)contents: Do modern diets starve our gut-microbial community?, Joyride: Brief post-antibiotic sugar spike gives pathogens a lift, Short and sweet: Three days in a sugar solution, and you’ve got your see-through tissue sample 
Image courtesy of Liang Feng

Bioengineering, Imaging, Research, Stanford News, Videos

How CLARITY offers an unprecedented 3-D view of the brain’s neural structure

How CLARITY offers an unprecedented 3-D view of the brain's neural structure

Last year, Stanford bioengineer Karl Deisseroth, MD, PhD, and colleagues in his lab announced their development of CLARITY, a process that renders tissue transparent, sparking excitement among the scientific community. As explained in the above video, released yesterday by the National Science Foundation, researchers had been unable to directly study the human brain’s circuitry because much of the organ is covered in an opaque tissue. But using CLARITY researchers can “chemically dissolve the opaque tissue in a post-mortem brain, and in place of that tissue, they insert a transparent hydrogel that keeps the brain intact and provides a window into the brain’s neural structure and circuitry.” For this reason, the technique is “hailed as an important advance in whole-brain imaging.”

Previously: Process that creates transparent brain named one of year’s top scientific discoveries, An in-depth look at the career of Stanford’s Karl Deisseroth, “a major name in science”, Peering deeply – and quite literally – into the intact brain: A video fly-through and Lightning strikes twice: Optogenetics pioneer Karl Deisseroth’s newest technique renders tissues transparent, yet structurally intact

Behavioral Science, Evolution, Imaging, Neuroscience, Research, Stanford News, Surgery

In a human brain, knowing a face and naming it are separate worries

In a human brain, knowing a face and naming it are separate worries

Alfred E. Neuman (small)Viewed from the outside, the brain’s two hemispheres look like mirror images of one another. But they’re not. For example, two bilateral brain structures called Wernicke’s area and Broca’s area are essential to language processing in the human brain – but only the ones  in the left hemisphere (at least in the great majority of right-handers’ brains; with lefties it’s a toss-up), although both sides of the brain house those structures.

Now it looks as though that right-left division of labor in our brains applies to face perception, too.

A couple of years ago I wrote and blogged about a startling study by Stanford neuroscientists Josef Parvizi, MD, PhD, and Kalanit Grill-Spector, PhD. The researchers recorded brain activity in epileptic patients who, because their seizures were unresponsive to drug therapy, had undergone a procedure in which a small section of the skulls was removed and plastic packets containing electrodes placed at the surface of the exposed brain. This was done so that, when seizures inevitably occurred, their exact point of origination could be identified. While  patients waited for this to happen, they gave the scientists consent to perform  an experiment.

In that experiment, selective electrical stimulation of another structure in the human brain, the fusiform gyrus, instantly caused a distortion in an experimental subjects’ perception of Parvizi’s face. So much so, in fact, that the subject exclaimed, “You just turned into somebody else. Your face metamorphosed!”

Like Wernicke’s and Broca’s area, the fusiform gyrus is found on each side of the brain. In animal species with brains fairly similar to our own, such as monkeys, stimulation of either the left or right fusiform gyrus appears to induce distorted face perception.

Yet, in a new study of ten such patients, conducted by Parvizi and colleagues and published in the Journal of Neuroscience,  face distortion occurred only when the right fusiform gyrus was stimulated. Other behavioral studies and clinical reports on patients suffering brain damage have shown a relative right-brain advantage in face recognition as well as a predominance of right-side brain lesions in patients with prosopagnosia, or face blindness.

Apparently, the left fusiform gyrus’s job description has changed in the course of our species’ evolution. Humans’ acquisition of language over evolutionary time, the Stanford investigators note, required the redirection of some brain regions’ roles toward speech processing. It seems one piece of that co-opted real estate was the left fusiform gyrus. The scientists suggest (and other studies hint) that along with the lateralization of language processing to the brain’s left hemisphere, face-recognition sites in that hemisphere may have been reassigned to new, language-related functions that nonetheless carry a face-processing connection: for example, retrieving the name of a person whose face you’re looking at, leaving the visual perception of that face to the right hemisphere.

My own right fusiform gyrus has been doing a bang-up job all my life and continues to do so. I wish I could say the same for my left side.

Previously: Metamorphosis: At the push of a button, a familiar face becomes a strange one, Mind-reading in real life: Study shows it can be done (but they’ll have to catch you first), We’ve got your number: Exact spot in brain where numeral recognition takes place revealed and Why memory and  math don’t mix: They require opposing states of the same brain circuitry
Photo by AlienGraffiti

Aging, Genetics, Imaging, Immunology, Mental Health, Neuroscience, Research, Women's Health

Stanford’s brightest lights reveal new insights into early underpinnings of Alzheimer’s

Stanford's brightest lights reveal new insights into early underpinnings of Alzheimer's

manAlzheimer’s disease, whose course ends inexorably in the destruction of memory and reason, is in many respects America’s most debilitating disease.  As I wrote in my article, “Rethinking Alzheimer’s,” just published in our flagship magazine Stanford Medicine:

Barring substantial progress in curing or preventing it, Alzheimer’s will affect 16 million U.S. residents by 2050, according to the Alzheimer’s Association. The group also reports that the disease is now the nation’s most expensive, costing over $200 billion a year. Recent analyses suggest it may be as great a killer as cancer or heart disease.

Alarming as this may be, it isn’t the only news about Alzheimer’s. Some of the news is good.

Serendipity and solid science are prying open the door to a new outlook on what is arguably the primary scourge of old age in the developed world. Researchers have been taking a new tack – actually, more like six or seven new tacks – resulting in surprising discoveries and potentially leading to novel diagnostic and therapeutic approaches.

As my article noted, several Stanford investigators have taken significant steps toward unraveling the tangle of molecular and biochemical threads that underpin Alzheimer’s disease. The challenge: weaving those diverse strands into the coherent fabric we call understanding.

In a sidebar, “Sex and the Single Gene,” I described some new work showing differential effects of a well-known Alzheimer’s-predisposing gene on men versus women – and findings about the possibly divergent impacts of different estrogen-replacement  formulations on the likelihood of contracting dementia.

Coming at it from so many angles, and at such high power, is bound to score a direct hit on this menace eventually. Until then, the word is to stay active, sleep enough and see a lot of your friends.

Previously: The reefer connection: Brain’s “internal marijuana” signaling implicated in very earliest stages of Alzheimer’s pathology, The rechargeable brain: Blood plasma from young mice improves old mice’s memory and learning, Protein known for initiating immune response may set up our brains for neurodegenerative disease, Estradiol – but not Premain – prevents neurodegeneration in woman at heightened dementia risk and Having a copy of ApoE4 gene variant doubles Alzheimer’s risk for women, but not for men
Illustration by Gérard DuBois

Cancer, Imaging, In the News, Patient Care, Stanford News, Technology

New technology enabling men to make more confident decisions about prostate cancer treatment

New technology enabling men to make more confident decisions about prostate cancer treatment

To watch and wait, or operate? There’s quite a bit of confusion, and a variety of differing opinions from the medical community, regarding prostate cancer treatment – so it’s no wonder that some men question whether the treatment path they’ve chosen is the right one. A new technology at Stanford, though, is hoping to alleviate some of the confusion and help with the decision-making process.

By using a combination of ultrasound and MRI imaging, Stanford physicians can use the resulting 3D images to get a far more detailed look at the level of cancer and its aggressiveness than they were able to in the past. Patients, in turn, will be empowered with the knowledge to make more confident decisions about how, and whether, to proceed with treatment. ABC7 News recently aired a story on the new technology.

Previously: Six questions about prostate cancer screening, Ask Stanford Med: Answers to your questions on prostate cancer and the latest research and Making difficult choices about prostate cancer

Big data, Imaging, Stanford News, Technology

Learning how we learn to read

Learning how we learn to read

Last week, as the 2014 Big Data in Biomedicine conference came to a close, a related story about the importance of computing across disciplines posted on the Stanford University homepage. The article describes research making use of the new Stanford Research Computing Center, or SRCC (which we blogged about here). We’re now running excerpts from that piece about the role computation, as well as big data, plays in medical advances.

letter - smallA love letter, with all of its associated emotions, conveys its message with the same set of squiggly letters as a newspaper, novel, or an instruction manual. How our brains learn to interpret a series of lines and curves into language that carries meaning or imparts knowledge is something psychology professor Brian Wandell, PhD, has been trying to understand.

Wandell hopes to tease out differences between the brain scans of kids learning to read normally and those who are struggling, and use that information to find the right support for kids who need help. “As we acquire information about the outcome of different reading interventions we can go back to our database to understand whether there is some particular profile in the child that works better with intervention 1, and a second profile that works better with intervention 2,“ said Wandell, who is also the Isaac and Madeline Stein Family Professor and a professor (by courtesy) of electrical engineering.

His team developed a way of scanning kids’ brains with magnetic resonance imaging then knitting the million collected samples together with complex algorithms that reveal how the nerve fibers connect different parts of the brain. “If you try to do this on your laptop, it will take half a day or more for each child,” he said. Instead, he uses powerful computers to reveal specific brain changes as kids learn to read.

Wandell is associate director of the Stanford Neurosciences Institute where he is leading the effort to develop a computing strategy – one that involves making use of SRCC rather than including computing space in their planned new building. He said one advantage of having faculty share computing space and systems is to speed scientific progress. “Our hope for the new facility is that it gives us the chance to set the standards for a better environment for sharing computations and data, spreading knowledge rapidly through the community,” he said.

Previously: Personal molecular profiling detects diseases earlier, New computing center at Stanford supports big data, Teaching an old dog new tricks: New faster and more accurate MRI technique quantifies brain matter, Study shows brain scans could help identify dyslexia in children before they start to read and Stanford study furthers understanding of reading disorders
Photo by Liz West

Imaging, In the News, Orthopedics, Research

Goo inside bones provides structural support, study finds

Goo inside bones provides structural support, study finds

As high-schoolers swarm the med school campus today, hold human brains and satisfy their taste for science, I can’t help but wish the show “You Can’t Do That on Television” still existed and that the producers would set up in the parking lot and slime each participant upon completion of the day. But a welcome alternative is news that scientists have discovered gooey matter inside human bones.

In a 60-Second Health piece, writer Dina Fine Maron explains how “a combination of imaging techniques and modeling has revealed that our bones are filled with a natural chemical goo that’s key to the bones’ function as support structures,” and that the information could be used to inform osteoporosis treatment and prevention. The researchers’ findings were published in the Proceedings of the National Academy of Sciences.

Previously: Exploring the use of yoga to improve the health and strength of bones, 419 million year-old fish fossil may reveal origins of the human jaw and  Teen girls become orthopaedic surgeons for a day

Cardiovascular Medicine, Imaging

A microscopic view of the calcification of heart tissue

A microscopic view of the calcification of heart tissue

hard_heart_tissue

Aortic valve calcification, which can be an early sign of heart disease, occurs when calcium deposits form on the aortic valve in the heart causing the soft tissue to harden. This striking image from the Wellcome Images Awards 2014 offers a microscopic view of clumps of calcium salts building up on the heart valve. A description on the winners’ photo gallery offers more detail about how it was created:

This image was produced using a type of scanning electron microscopy called density-dependent colour scanning electron microscopy. In this method, images are taken of a sample using two different detectors, one which records topographical information about the surface of the sample and one which records information about its density. A different colour is assigned to each and the images are then superimposed to produce a composite image like the one you see here. In this particular image, the orange colour identifies denser material (calcified material composed of calcium phosphate), while structures that appear in green are less dense (corresponding to the organic component of the tissue).

Previously: Big hand, beautiful biofilms, Image of the Week: One of 2013′s “coolest” microscopic images, Image of the Week: Microscopic view of lung surfactant and Touring the microscopic worlds of the human body
Photo by Sergio Bertazzo, Wellcome Images

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