Tag Archives: Medical

Compact light source improves CT scans

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The Compact Light Source by Palo Alto-based Lyncean Technologies Inc. generates X-rays suitable for advanced tomography. The car-sized device is a miniature version of football-field-sized X-ray generators known as synchrotrons and it emerged from basic research at SLAC in the late 1990s and early 2000s.
Credit: Lyncean Technologies Inc.

A new study shows that the recently developed Compact Light Source (CLS) — a commercial X-ray source with roots in research and development efforts at the Department of Energy’s SLAC National Accelerator Laboratory — enables computer tomography scans that reveal more detail than routine scans performed at hospitals today. The new technology could soon be used in preclinical studies and help researchers better understand cancer and other diseases.

With its ability to image cross sections of the human body, X-ray computer tomography (CT) has become an important diagnostic tool in medicine. Conventional CT scans are very detailed when it comes to bones and other dense body parts that strongly absorb X-rays. However, the technique struggles with the visualization and distinction of “soft tissues” such as organs, which are more transparent to X-rays.

“Our work demonstrates that we can achieve better results with the Compact Light Source,” says Professor for Biomedical Physics Franz Pfeiffer of the Technical University of Munich in Germany, who led the new study published April 20 in the Proceedings of the National Academy of Sciences. “The CLS allows us to do multimodal tomography scans — a more advanced approach to X-ray imaging.”

More than One Kind of Contrast

The amount of detail in a CT scan depends on the difference in brightness, or contrast, which makes one type of tissue distinguishable from another. The absorption of X-rays — the basis for standard CT — is only one way to create contrast.

Alternatively, contrast can be generated from differences in how tissues change the direction of incoming X-rays, either through bending or scattering X-ray light. These techniques are known as phase-contrast and dark-field CT, respectively.

“Organs and other soft tissues don’t have a large absorption contrast, but they become visible in phase-contrast tomography,” says the study’s lead author, Elena Eggl, a researcher at the Technical University of Munich. “The dark-field method, on the other hand, is particularly sensitive to structures like vertebrae and the lung’s alveoli.”

Shrinking the Synchrotron

However, these methods require X-ray light with a well-defined wavelength aligned in a particular way — properties that conventional CT scanners in hospitals do not deliver sufficiently.

For high-quality phase-contrast and dark-field imaging, researchers can use synchrotrons — dedicated facilities where electrons run laps in football-stadium-sized storage rings to produce the desired radiation — but these are large and expensive machines that cannot simply be implemented at every research institute and clinic.

Conversely, the CLS is a miniature version of a synchrotron that produces suitable X-rays by colliding laser light with electrons circulating in a desk-sized storage ring. Due to its small footprint and lower cost, it could be operated in almost any location.

“The Large Hadron Collider at CERN is the world’s largest colliding beam storage ring, and the CLS is the smallest,” says SLAC scientist Ronald Ruth, one of the study’s co-authors. Ruth is also chairman of the board of directors and co-founder of Palo Alto-based Lyncean Technologies Inc., which developed the X-ray source based on earlier fundamental research at SLAC. “It turns out that the properties of the CLS are perfect for applications like tomography.”

More Modes, Finer Detail

In the recent study, the researchers reported the first “multimodal” CT scan with the CLS: They recorded all three imaging modes — absorption, phase contrast and dark field — at the same time. Using a total of 361 two-dimensional X-ray images of an infant mouse taken from different directions, the scientists generated cross-section images of the animal.

“The absorption images only show bones and air-filled organs,” Eggl says. “However, the phase-contrast and dark-field images reveal much more detail, showing different organs such as the heart and liver. We can even distinguish different types of fat tissue, which is not possible with absorption-based CT scans.”

Using a standard sample of chemically well-defined liquids, the scientists also demonstrated that they could not only visualize but also quantify differences in their properties — information that can be applied to various body tissues and that is only obtained when combining all three tomography modes.

Implications for Cancer, Materials

The success of this research, which was done on a CLS prototype, has led to the commissioning of the first commercial device.

The researchers’ next goal is to use the CLS for phase-contrast and dark-field CT in preclinical studies — an approach that could help visualize cancer. “We work closely together with two clinics to study tumors,” Eggl says. “One of our plans is to image breast tissue samples and also entire breasts after mastectomy to better understand the clinical picture of breast cancer.”

Besides medical applications, multimodal tomography could also open up new possibilities in materials science, for instance, in studies of extremely durable and light-weight carbon fibers and other fibrous materials, where the X-ray absorption contrast provides little information.

Please follow this link to Science Daily for the original story.

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A New High-Speed MRI Technique Is Fast Enough To Record Someone Singing

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It’s a remarkable technology capable of looking inside a human being, but magnetic resonance imaging—or MRI—machines are finicky and require a patient to remain absolutely still while it does its thing. But researchers at the University of Illinois have found a way to capture up to 100 frames per second on an MRI machine allowing them to record patients in motion.

The need for a faster MRI technique arose when a faculty member at the University of Illinois’ Beckman Institute for Advanced Science and Technology wanted to study how the muscles of the larynx worked in elderly patients while singing, in an attempt to help give them more powerful and pronounced voices. The problem with using MRI machines was that they could only capture images at around ten frames per second which was far too slow to study what was going on with the 100 or so muscles required to sing.

So Zhi-Pei Liang, an electrical and computer engineering professor at the institute, worked with his team to develop a new methodology to extract more frames from an MRI machine—which is a far cheaper solution than trying to rebuild and redesign one of the incredibly expensive devices from the ground up. Here’s how the new technique they came up with is described in an issue of Magnetic Resonance in Medicine:

An imaging method is developed to enable high-speed dynamic speech imaging exploiting low-rank and sparsity of the dynamic images of articulatory motion during speech. The proposed method includes: (a) a novel data acquisition strategy that collects spiral navigators with high temporal frame rate and (b) an image reconstruction method that derives temporal subspaces from navigators and reconstructs high-resolution images from sparsely sampled data with joint low-rank and sparsity constraints.

To read the full story and for more information please follow this link to Gizmodo.

Design Library Lets Researchers Print their Own Syringe Pumps

Furnishing a research lab can be pretty expensive. Now a team led by an engineer at Michigan Technological University has published an open-source library of designs that will let scientists slash the cost of one commonly used piece of equipment: the syringe pump.

Syringe pumps are used to dispatch precise amounts of liquid, as for drug delivery or mixing chemicals in a reaction. They can also cost hundreds or even thousands of dollars.

Joshua Pearce and his team of Michigan Tech students published the library of free syringe-pump designs, which anyone can make on a RepRap 3D printer just for the cost of the plastic filament. Better yet, the designs are perfectly customizable.

“Not only have we designed a single syringe pump, we’ve designed all future syringe pumps,” said Pearce.  “Scientists can customize the design of a pump for exactly what they are doing, just by changing a couple of numbers in the software.”

The library includes recipes for most parts of a syringe pump. You’ll have to buy the small electric stepper motor that drives the liquid, some simple hardware and the syringe itself, which is inexpensive.

The team also went a little further, incorporating a low-cost, credit card-sized Raspberry Pi computer as a wireless controller. “That way, you can link the syringe pump to the network, sit on a beach in Hawaii and control your lab,” Pearce said. “Plenty of people can have access, and you can run multiple experiments at the same time. Our entire single-pump system costs only $50 and can replace pumps that run between $250 and $2,500.”

It costs more to make a double-pump system, about $120, but it replaces a commercial system that costs $5,000.

That said, Pearce believes someone will figure out how to make them better. “The international scientific open-source lab community is growing rapidly. From UC Berkeley’s Tekla Lab to Sensorica in Montréal and OpenLabTools at the University of Cambridge, we are all working together to make science cheaper, faster and better. I’m sure someone will improve our designs and share their results with us and the rest of the community. That’s the beauty and power of open source,” he said.

Megan Frost, a biomedical engineer at Michigan Tech, uses syringe pumps from Pearce’s library to introduce agents into cell cultures.

“What’s beautiful about what Joshua is doing is that it lets us run three or four experiments in parallel, because we can get the equipment for so much less,” she said. “We’d always wanted to run experiments concurrently, but we couldn’t because the syringe pumps cost so much. This has really opened doors for us.”

The work is described in the paper “Open-source Syringe Pump Library,” published in PLoS One and coauthored by Pearce, graduate student Bas Wijnen, research scientist Gerald Anzalone and undergraduate Emily Hunt. The hardware plans, designs, and source code for the pumps is available for free at http://www.appropedia.org/Open-source_syringe_pump.

Pearce is an associate professor with appointments in both the Department of Materials Science and Engineering and the Department of Electrical and Computer Engineering at Michigan Tech.

Michigan Technological University (www.mtu.edu) is a leading public research university developing new technologies and preparing students to create the future for a prosperous and sustainable world. Michigan Tech offers more than 130 undergraduate and graduate degree programs in engineering; forest resources; computing; technology; business; economics; natural, physical and environmental sciences; arts; humanities; and social sciences.

For more information and the original story follow the source link below.

Source: MICHIGAN TECH NEWS

Implant Device for Stopping Uncontrolled Seizures

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Surgeons at Comprehensive Epilepsy Center Say Pacemaker-like RNS System Provides Innovative Approach to Stop Seizures Before They Start

Newswise — NYU Langone Medical Center last month became the first hospital outside of a clinical trial site to implant a pacemaker-like device in the brain that may be a game-changer for patients with epilepsy.

The device, called the RNS System, was implanted April 17, 2014 in a patient with seizures that previously could not be controlled with medication, or intractable epilepsy, by Werner Doyle, MD, an associate professor in the Department of Neurosurgery at NYU Langone. The patient has recovered completely from the surgery.

The first-of-its-kind device is similar to an implantable cardioverter-defibrillator (ICD), which delivers electrical pulses to the heart to prompt it to beat a normal rhythm and provides a new alternative treatment to vagus nerve stimulation and surgical removal of the focus site – parts in the brain where the seizures originate — for people with intractable epilepsy.

Prior to last month’s surgery, the only implants of the seizure-reducing medical device took place at U.S. medical centers that had previously researched the device’s effectiveness and safety, making NYU Langone the first non-study hospital in the U.S. and New York metropolitan area to offer the RNS System to patients.

“Medically intractable epilepsy is often a debilitating disorder that puts sufferers at risk from sudden loss of consciousness and uncontrolled movements. It stigmatizes patients and restricts their independence,” said Dr. Doyle. “Epilepsy surgery is an important therapeutic option for patients, which can significantly or completely control their seizures and return their lives to normal. The RNS device improves our ability to control seizures with surgery and now offers patients who may not have been surgical candidates in the past a surgical option.”

According to the Centers for Disease Control and Prevention, about 2.3 million Americans suffer from epilepsy, with about one in 26 people expected to be diagnosed in their lifetimes. Approximately one-third of patients do not respond to medications and face major challenges with daily living. Uncontrolled seizures may interfere with normal activities such as working, going to school and driving. Patients also face increased risk for anxiety, depression, injury, brain damage, and in rare cases, death.

The RNS System, manufactured by NeuroPace Inc. of Mountain View, Calif., is a responsive stimulation device that’s implanted in the skull along with brain electrodes to detect abnormal electrical activity in the brain associated with seizures. After two or more weeks of recording the activity, doctors program the device to specifically respond to these abnormal signals by delivering imperceptible electrical pulses to the brain that normalize the activity. The device essentially “reboots” the portion of the brain where the seizure is originating, thereby effectively interrupting the abnormal electrical activity before it spreads or causes its unwanted effects.

The RNS System received pre-market approval from the Food and Drug Administration in November 2013 to treat patients’ seizures that have not been controlled by two or more antiepileptic medications.

In clinical trials performed at medical centers across the U.S., including at Saint Barnabas Medical Center in New Jersey by Dr. Doyle and Orrin Devinsky, MD, director of the Comprehensive Epilepsy Center at NYU Langone, 55 percent of patients experienced a 50 percent or greater reduction in seizures two years post implantation.

“The RNS System represents one of the most important and innovative therapies to treat people with epilepsy,” says Dr. Devinsky. “This new surgical therapy uses information to target and shut down points in the brain where seizures start without removing tissue, providing a novel option for patients with uncontrolled seizures.”

For more information follow the source link below.

Source: Newswise

New ‘T-ray’ tech converts light to sound for weapons detection, medical imaging

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ANN ARBOR—A device that essentially listens for light waves could help open up the last frontier of the electromagnetic spectrum—the terahertz range.

So-called T-rays, which are light waves too long for human eyes to see, could help airport security guards find chemical and other weapons. They might let doctors image body tissues with less damage to healthy areas. And they could give astronomers new tools to study planets in other solar systems. Those are just a few possible applications.

But because terahertz frequencies fall between the capabilities of the specialized tools presently used to detect light, engineers have yet to efficiently harness them. The U-M researchers demonstrated a unique terahertz detector and imaging system that could bridge this terahertz gap.

“We convert the T-ray light into sound,” said Jay Guo, U-M professor of electrical engineering and computer science, mechanical engineering, and macromolecular science and engineering. “Our detector is sensitive, compact and works at room temperature, and we’ve made it using an unconventional approach.”

The sound the detector makes is too high for human ears to hear.

The terahertz gap is a sliver between the microwave and infrared bands of the electromagnetic spectrum—the range of light’s wavelengths and frequencies. That spectrum spans from the longest, low-energy radio waves that can carry songs to our receivers to the shortest, high-energy gamma rays that are released when nuclear bombs explode and radioactive atoms decay.

In between are the microwave frequencies that can cook food or transport cell phone signals, the infrared that enables heat vision technologies, the visible wavelengths that light and color our world, and X-rays that give doctors a window under our skin.

For more information and the full story follow the source link below.

Source: University of Michigan News

Bats confirmed as SARS origin

A team of international scientists has isolated a very close relative of the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) from horseshoe bats in China, confirming them as the origin of the virus responsible for the 2002-3 pandemic.

The SARS-CoV pandemic killed 774 people of the 8094 people infected, a case fatality ratio of almost 10 per cent. With cases diagnosed across the world, the pandemic had an impact on international travel and trade.

The research team, led by Professor Shi Zhengli from Wuhan Institute of Virology, Chinese Academy of Sciences and including CSIRO and Duke-NUS scientist Professor Linfa Wang, have just had their breakthrough results published in the prestigious journal Nature.

The results will help governments design more effective prevention strategies for SARS and similar epidemics.
While researchers globally have previously used genetic sequencing to demonstrate that bats are the natural reservoirs of SARS-like CoVs, this is the first time that live virus has been successfully isolated from bats to definitively confirm them as the origin of the virus.

The team successfully isolated a SARS-like CoV, named SL-CoV WIV1, directly from faecal samples of Chinese Horseshoe bats using the world renowned bat virus isolation methodology developed by scientists at CSIRO’s Australian Animal Health Laboratory in Geelong.

The results will help governments design more effective prevention strategies for SARS and similar epidemics.

Horseshoe bats are found around the world, including Australia and play an important ecological role. Their role in SARS-CoV transmission highlights the importance of protecting the bat’s natural environment so they are not forced into highly populated urban areas in search of food.

This work is part of CSIRO’s ongoing commitment to protect Australia from biosecurity threats posed by new and emerging infectious diseases.

Source: csiro.au

Hospital To Use Microfluid Prototype For Diagnosing Tumors

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Photo: Lucas Laursen

Chemist Emmanuel Delamarche held a thin slice of human thyroid tissue on a glass slide between his fingers. The tissue poses a mystery: does it contain a tumor or not? Delamarche, who works at IBM Research in Zurich, Switzerland, turned the slide around in his hand as he explained that the normal method of diagnosing a tumor involves splashing a chemical reagent, some of which are expensive, onto the uneven surface of the tissue and watching for it to react with disease markers. A pathologist “looks at them under a microscope, and he’s using his expertise, his judgment, and looks at what chemical he used, what type of color he can see and what part and he has to come up with a diagnosis,” Delamarche says, “he has a very, very hard job, OK?”

IBM is already good at precise application of materials to flat surfaces such as computer chips. Human tissue, sliced thin enough, turns out to receptive to the company’s bag of tricks too. Delamarche, turning to one of three machines on lab benches, explained that a few years ago his team began trying to deliver reagents with more precision. University Hospital Zurich will be testing the results over the next few months.

The idea was that instead of a sprawling blot occupying most of a tissue sample, a tiny tube something like an inkjet printer could deliver many droplets onto the tissue. Pathologists might put multiple reagents on a single fingernail-sized tissue sample, saving them the need for more samples and surgery. They might make better-informed diagnoses because the printer-like machine would allow them to control how much reagent to place on the tissue and where it goes. Pathologists could also compare the effects of well-measured doses on suspected cancerous parts. “We are interested in maybe thinking about technology to go from qualitative info to more quantitative information,” Delamarche says.

But that precise delivery of the reagents proved elusive. Some of it spilled outside the target area. In 2011 Delamarche and colleagues announced a vertical microfluidic probe, that unlike previous microfluidic probes was not parallel to the target surface. It consisted of a glass and silicon wafer about one square centimeter with one channel about a micrometer across that shot liquid to the target and another channel that vacuumed up any excess. “The trick, or the invention actually, that we had was to put a second aperture that continuously re-aspirates what we inject,” Delamarche says. Today the team can create spots just 50 micrometers across, though he says the sweet spot for diagnoses may be more like a few hundred micrometers.

The microfluidic machine is part of a trend toward keeping samples put and moving the thing that analyzes them, according to a recent review in Lab on a Chip.

The technology is attractive both to pathologists, such as those at University Hospital Zurich, and to basic researchers, with whom Delamarche and mechanical engineer Govind Kaigala can share a larger, more customizable version in their lab.

Source: IEEE Spectrum

Immune System Discovery Could Lead to Vaccine to Prevent Mono, Some Cancers

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Development of a vaccine against Epstein-Barr virus (EBV) has taken a step forward with the Canadian discovery of how EBV infection evades detection by the immune system.

EBV causes infectious mononucleosis and cancers such as Hodgkin’s lymphoma and nasopharyngeal carcinoma, which is the most common cancer in China, as well as opportunistic cancers in people with weakened immune systems. A member of the herpes virus family that remains in the body for life, the virus infects epithelial cells in the throat and immune cells called B cells.

The researchers discovered that the virus triggers molecular events that turn off key proteins, making infected cells invisible to the natural killer T (NKT) immune cells that seek and destroy EBV-infected cells.

“If you can force these invisible proteins to be expressed, then you can render infected cells visible to NKT cells, and defeat the virus. This could be key to making a vaccine that would provide immunity from ever being infected with EBV,” says Dr. Rusung Tan, the study’s principal investigator. Dr. Tan is a scientist and director of the Immunity in Health & Disease research group at the Child & Family Research Institute at BC Children’s Hospital, and a professor in the Department of Pathology at the University of British Columbia.

The findings were published this week in the print edition of the scientific journal Blood.

For this study, the researchers looked at cells from infected tonsils that had been removed from patients at BC Children’s Hospital by Dr. Frederick Kozak. The researchers infected the tonsillar B cells with EBV, and then combined some of these cells with NKT cells. They found that more NKT cells led to fewer EBV-infected cells, while an absence of NKT cells was associated with an increase in EBV-infected cells.

Source: Science Daily

Finnish Doctors Are Prescribing Video Games for ADHD

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A physiotherapy patient using a Kinect-based game in treatment. Photo courtesy Serious Games Finland

There’s a problem with the drugs used in mental health care: You have to be on them for them to work. Even then, they can be expensive and have detrimental side effects.
 
Ville Tapio had an idea to do it better. He runs a private psychiatry center in Helsinki, and psychiatrists had told him they were reluctant in particular to hand out drugs for patients with attention deficit hyperactivity disorder (ADHD). ADHD drugs are psychostimulants, they are frequently abused, and kids can be prescribed them young and kept on a regimen for years.

Tapio’s alternative? Getting people with mental health concerns to play video games. They’re special video games, of course—ones that can change how your brain works, with a technique loosely termed gameified neuroplasticity therapy.

The idea isn’t totally out of the blue. The University of Helsinki is well known for its neuroscience, with researchers already investigating how brain activity changes when people do different things. Scientists there have already tinkered around with game play, checking out local Helsinki production Angry Birds to test why the game was so addictive, and it’s all part of a push by Finnish developers to build games that do good.

But using games to change people’s brains for health reasons is an ambitious and relatively new concept. Still, Helsinki has the scientists and the gaming companies—Angry Birds developer Rovio is just one—to give the idea a proper look. Now, researchers also have cash: Tapio’s company Mental Capital Care received 790,000 euro in funding from Finnish investment board Tekes last year to test out a game designed to cure the symptoms of ADHD.

The new interest in gaming in treatment is fueled partly because brain wave scanning headsets have come down in cost, making it a more realistic option outside the lab. Neurogames work with EEG headsets, which place small electrodes directly on your scalp to measure brain waves. While EEG technology has been around in medicine for ages, only recently have cheaper commercial versions of EEG caps come on the market.

One such EEG cap is the Emotiv, which has become popular with researchers looking to move beyond the restrictions of fMRI brain studies. For one, it’s hard to study the brain’s reactions to natural stimuli when a person is inside an MRI machine. A brain cap, on the other hand, is mobile enough for users to utilize in their daily lives, an advantage researchers hope will help users hack their brains.

Emotiv’s brain-controlled headset was originally designed for regular gaming, but has since found fans in neuro researchers.

Continue reading article by clicking the source link below.

Source: Motherboard

WHO: H7N9 Virus ‘The Most Lethal So Far’

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As the death toll from China’s bird flu outbreak rose to 22 with news of another victim in eastern Zhejiang Province, the World Health Organization warned the H7N9 virus was one of the most lethal that doctors and medical investigators had faced in recent years.

“This is an unusually dangerous virus for humans,” Keiji Fukuda, WHO’s assistant director-general for health, security and the environment told a news conference in Beijing Wednesday.

“We think this virus is more easily transmitted from poultry to humans than H5N1,” he added, referring to the bird flu outbreak between 2004 and 2007 that claimed 332 lives.

“This is definitely one of the most lethal influenza viruses that we have seen so far.”

As investigations continue into the possible sources of infection, Fukuda warned that authorities were still struggling to understand the virus. The WHO said China must brace for continued infections.

“I want to give you a caveat, or give you a little bit of context. We really are at the beginning of our understanding of this virus,” Fukuda said. “(The situation remains) complex, difficult and it is evolving.”

So far there is no evidence of sustained human-to-human transmission, the authorities say.

“We do want to note, however, that if limited person-to-person transmission is demonstrated in the future, this really will not be surprising,” Fukuda warned, adding that it was critical to remain vigilant, monitoring the virus’s spread and mutation.
“We are not sure that the clusters were caused by common exposure to a source of the virus or were due to limited person-to-person transmission,” he said. “Moreover we have not seen sustained person-to-person transmission.”

While some elements of the outbreak have baffled investigators — specifically why the virus tends to target an elderly demographic and the fact that it is asymptomatic or mild in some cases and lethal in others — authorities have claimed some significant victories in the fight against a pandemic.

Anne Kelso, the director of a WHO-collaborating research center, said researchers had seen a “dramatic slowdown” in human cases in Shanghai after the city’s live poultry market was shut on April 6. Describing the finding as “very encouraging,” she said evidence suggests the closure of live poultry markets is an effective way to stop the spread of the virus.

The joint inspection team from China’s National Health and Family Planning Commission and the World Health Organization also found that, so far, no migratory birds have tested positive for the virus, taking another worrying route of transmission out of the equation.

It said the H7N9 virus is only being found in chickens, ducks and pigeons at live poultry markets.

WHO officials said there are already efforts underway in other countries to develop a vaccine after Chinese officials admitted international help would be needed with this.

Meanwhile, the National Health and Family Planning Commission said in its daily update on H7N9 cases that a total of 108 H7N9 cases have been reported in China, including 22 deaths. Most cases have been confined to Shanghai and neighboring provinces in eastern China.

Source: CNN