Scientists measured the first in vivo images of stimulated current within the brain using an imaging method that may improve reproducibility and safety, and help understand the mechanisms of action of electrical stimulation.
Finding could make pricey, massive scanners a thing of the past.
Have you ever wondered how your diet affects your heart? Or your liver? And not just for your general health, but at a molecular level? What is that cheeseburger doing to your heart, anyway?
Matt Merritt, an associate professor of biochemistry and molecular biology at the University of Florida (UF), wants to help answer those questions. He studies the role of metabolic pathways in heart failure and fatty liver disease. Specifically, he looks at ATP — the molecule used by all living things to store and transport energy. The results of his work have the potential to improve our understanding and treatment of illnesses as wide-ranging as heart disease, diabetes and cancer.
Using nuclear magnetic resonance (NMR) magnets and instrumentation available at the National MagLab's AMRIS Facility at UF, Merritt studies how carbon is involved in ATP generation. However, phosphorus, another important element in the final step of ATP generation, has been beyond his reach because the special tool required to study it wasn’t available. Studying phosphorous requires a certain kind of probe — a stick-like piece of equipment that holds the sample and allows the scientist to insert it into the magnet.
Now, thanks to the addition of a new cryoprobe at the AMRIS Facility, Merritt and other MagLab users will be able to monitor phosphorus dynamics. With its electronics operating at very low, cryogenic temperatures, this probe enables monitoring of phosphorous-containing compounds at physiologic concentrations and will allow Merritt's group to gain a fuller understanding of metabolism (instead of studying carbon movement in isolation).
The new probe is larger (with a 10-mm diameter sample space) than existing cryoprobes in the facility and, in addition to phosphorus, can detect carbon and sodium isotopes, enabling researchers to obtain higher sensitivity data on larger samples. This probe is connected to a commercially built dynamic nuclear polarization (DNP) system, another recent addition to the AMRIS Facility. The new DNP system, called HyperSense, is more automated than the facility's current DNP set-up, and can be operated by a single person, making it more user-friendly. The HyperSense, which is attached to the 600 MHz 51 mm NMR & MRI/S System and the new cryoprobe, will be available to users by the fall of 2018.
Photo: Researchers Ram Khattri (left) and Mukundan Ragavan work with the new cryoprobe. Photo by Elizabeth Webb.
Story by Elizabeth Webb.
This instrument is located at the MagLab's AMRIS Facility at the University of Florida in Gainesville.
Scientists are welcoming a new MRI machine at the National MagLab that provides the best spatial resolution available for human imaging, making it a powerful tool for nationwide, multi-site health research.
Manufactured by Siemens, the state-of-the-art, whole-body scanner is powered by a 3-tesla magnet (tesla is a unit of magnetic field strength). But it's not the machine’s main magnetic field — on a par with many hospital MRIs — that makes the instrument special. Rather, the unit features the most powerful gradient magnet fields available, which help generate very sharp images of very tiny anatomical structures.
“Gradients provide the high spatial resolution in MRI, and with the new system we get the localization we need for small structures,” said Joanna Long, director of the MagLab's Advanced Magnetic Resonance Imaging and Spectroscopy (AMRIS) facility at the University of Florida, where the new instrument is located.
For anyone who has been inside an MRI machine, the gradient magnetic fields are responsible for that unpleasant racket you hear; technicians trigger them to target different areas of the body. But they also help generate more precise images – in this case, around a millimeter in resolution, allowing scientists to see bundles of neurons inside the brain. (Learn more about how MRI machines work).
As one of a number of similar machines recently installed around the country, the new system will enable researchers working at AMRIS to participate in large-scale, multi-site health studies. For example, some AMRIS researchers are using the machine as part of a years-long study to track brain cognitive development in adolescents. Others will use it for research on Alzheimer’s and Parkinson’s disorders. Glenn Walter, an associate professor in physiology and functional genomics at the University of Florida, is using it to develop MRI techniques to assess how effective drugs are at treating muscular dystrophy, a less invasive approach than muscle biopsy.
By allowing MagLab users to participate in such longitudinal studies, the $3 million system will yield high research dividends. “It's a really good example of how the magnetic resonance research program at the MagLab can leverage something bigger,” Long said.
To celebrate a trio of recent upgrades, including the new MRI machine, added dynamic nuclear polarization capabilities, and a new console for the 11-tesla MRI/S system, AMRIS hosted a reception and symposium this week.
Text by Kristen Coyne; Image courtesy of AMRIS.
This week at the lab, engineers are installing a new "control center" for one of our magnet systems that will result in faster experimental set-up times, more sensitive readings, and detailed information for functional magnetic resonance imaging (MRI) experiments — all contributing to a wide range of neuroscience applications, such as pharmacological MRI.
The beneficiary of this significant upgrade is an 11.1 tesla magnet located within the Advanced Magnetic Resonance Imaging and Spectroscopy (AMRIS) Facility, located at the University of Florida (UF). Used primarily for imaging the three-dimensional structure of living organisms, the system combines high magnetic fields with a particularly large bore (40 cm) and strong magnetic field gradients that allow large samples to be imaged with sub-millimeter resolution.
Scientists will use the magnet's new, custom-built control center — a custom-built Bruker AV3HD console with Paravision 6.0.1. — to program experiments, sending radio frequency pulses on a nanosecond scale and receiving signals back with information on their sample. It will support growing research in developing preclinical models for a variety of diseases, including the research program of new faculty member Matthew Merritt, an expert in in vivo metabolic flux measurements.
Please visit the page on the 11.1 tesla MRI/S system for more details.
This new console is made possible by joint funding from the MagLab and from UF’s McKnight Brain Institute, College of Medicine, and Division of Sponsored Programs.
Text and photo by Elizabeth Webb.
This week at the lab, scientists from across North America are learning the theory and practice of radio frequency (RF) coils.
RF coils are used in magnetic resonance imaging (MRI) to transmit and receive RF signals. The MagLab’s Advanced Magnetic Resonance Imaging and Spectroscopy (AMRIS) Facility at the University of Florida has an entire lab devoted to RF coil manufacture and development, led by RF engineer Malathy Elumalai.
In response to a growing need for visiting scientists to be able to troubleshoot and design their own RF coils, Elumalai is sharing her expertise at this week’s inaugural coil workshop. Empowering scientists to make their own coils makes sense. The demand for specialized coils has outpaced the rate at which Elumalai can design them. Additionally, sometimes the coils break, causing an experiment to come to a halt.
Throughout this week’s workshop, participants will learn the physics behind RF coils and be trained in specialized software for designing and modeling how the coils will behave under different magnetic fields and with different samples. Participants also have the chance to build their own coil and test it in the MagLab’s 4.7 tesla imaging magnet.
How do RF coils in MRI machines work? First, the coil transmits an RF signal, which produces a magnetic field perpendicular to the one already being produced by the magnet. Then, the same RF coil (or a separate one) receives signals indicating how the nuclear spins inside the subject are relaxing. This information is then processed as an image. Without RF coils, there’d be no "I" (imaging) in MRI!
The workshop is an example of the ongoing training we offer our "users" so that they can make the most of their time with our magnets. The MagLab also offers a User Summer School and a Theory Winter School once a year.
Text and image by Elizabeth Webb.
Scientists analyzing maize affected by southern leaf blight determine the molecular structures of so-called “death acids.”
This week at the lab our new chief scientist is on the road, connecting the dots that are the National MagLab’s many instruments, techniques and experts.
Physicist Laura Greene, who was named the lab’s chief scientist last year, traveled from the lab’s Florida State University headquarters to the University of Florida in Gainesville, home to two of the lab’s seven user facilities: the High B/T Facility and the Advanced Magnetic Resonance Imaging and Spectroscopy facility (AMRIS).
Greene (pictured above left with Tom Mareci and Joanna Long of AMRIS) will learn about the special capabilities the facilities offer, including dynamic nuclear polarization (DNP), a promising technique under development at AMRIS and at the MagLab’s Tallahassee-based Nuclear Magnetic Resonance Facility. More familiar to biologists and chemists, DNP may also be a powerful tool for condensed matter physicists, said Greene. President-elect of the American Physical Society, Greene says a big part of her MagLab job will be identifying and building these types of fertile, cross-disciplinary relationships.
When scientists learn from colleagues at a different facility or lab about the research they are working on it, "People are astounded and excited by it," said Greene. "But then they go back and they’re busy. So it’s going to be my job to help keep the flywheel going … to keep it as single MagLab, make sure we learn from each other."
Greene hopes the connections she is fostering will result both in more scientific publications authored by MagLab staff from multiple facilities as well as publications spawned by collaborations with other national labs and industry. Through her work with the Center for Emergent Superconductivity, Greene has close ties to both Brookhaven and Argonne national laboratories.
Photo by Elizabeth Webb / Text by Kristen Coyne
When molecules are forced to pass through narrow holes in membranes, they must move one-by-one in single file. When this “No Passing!” rule is in effect, researchers have recently made the surprising discovery that mixing two gases can lead to faster motion of some of the molecules through the narrow holes.