Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

JLab, College of W&M researchers study radiation blockers

22.04.2005


JLab, College of W&M researchers study radiation blockers while conducting nuclear imaging of Iodine uptake in mouse tissues



Scientists have found that a dose five times higher than the FDA-recommended dosage of potassium iodide in the event of a nuclear accident is needed to protect small animals effectively from radioactive iodide in medical imaging procedures. The long-term animal nuclear imaging project is being conducted by a collaboration of biology and physics researchers from the Department of Energy’s Jefferson Lab and The College of William & Mary (CWM).

The research was conducted at the CWM with a Jefferson Lab and CWM-built medical imaging system to perform investigational studies of mice. Bob Welsh, a JLab/CWM jointly appointed professor, is one researcher working on the project. The research demonstrates that scientists can learn about how the body uses certain substances of interest - such as insulin, the fat-regulating protein leptin and a wide range of other biological compounds - by tracking how these substances move through the body of a mouse.


"The way we follow those substances is to attach to them a radioactive isotope of iodine, Iodine-125. Iodine-125 emits a low-energy gamma ray," Welsh says, "It’s not a tremendous amount of energy, but it’s easy to track with these very precise detectors that have been designed and built by the Jefferson Lab Detector Group."

The thyroid needs iodine to regulate metabolism and is unable to distinguish between regular dietary iodine and ingested radioactive iodine. So the researchers weren’t surprised when, in the course of the project, they noticed that the mice subjects’ thyroids always absorbed a significant amount of radioactive iodine. In addition to being potentially bad for the mouse, the thyroid’s absorption of radioactive iodine made the images difficult to interpret and could provide false-positive readings or possibly obscure substantial iodine uptake in nearby tissues.

The team decided to test what would happen if they gave the mice potassium iodide, the FDA-recommended drug for blocking radioactive iodine absorption by the thyroid in the event of a nuclear accident, before exposing the mice to a form of radioiodine used in imaging studies. CWM undergraduate William Hammond, who will be presenting the team’s findings at the American Physical Society (APS) April Meeting, Session E12.0004, participated in this phase of the research for his senior thesis project.

The researchers started with the potassium iodide dose that’s recommended for humans in the event of a nuclear incident, 130 mg (milligrams), and scaled that down to the mass of the mouse. They administered a liquid form of the drug to mice, injected the radioiodine for imaging an hour later, and then imaged the mouse.

"What we noticed was this: the dose that was exactly the scaled human dose did not completely block the uptake of radioiodine. But when we tried three times, five times, ten times the scaled human dose, we obtained results that indicate that ten times the human dose blocks 1.5-2 times better, though five times is just about as good as ten times," Welsh says.

The researchers recognized that the extra benefit gained by the largest potassium iodide dose administered could in some cases be outweighed by potential side effects. To protect their mice in future imaging studies, they’re planning to use the potassium iodide dose that’s five times the scaled-down human dose.

As for larger implications, the study should not simply be scaled-up and applied to humans. "It could say that a mouse’s metabolism is so different from a human’s that you can’t just scale the human dose down for mice. But when it comes to small animals, I think the results should be taken into consideration," Welsh notes.

This research was made possible by a collaboration of Jefferson Lab and College of William researchers, including CWM physicists Robert Welsh, Julie Cella, Coleen McLoughlin, Kevin Smith and William Hammond; CWM biologists Eric Bradley and Margaret Saha; CWM applied science graduate student Jianguo Qian; and Jefferson Lab Detector Group scientists Stan Majewski, Vladimir Popov, Mark Smith and Drew Weisenberger.

Kandice Carter | EurekAlert!
Further information:
http://www.jlab.org

More articles from Physics and Astronomy:

nachricht Structured light and nanomaterials open new ways to tailor light at the nanoscale
23.04.2018 | Academy of Finland

nachricht On the shape of the 'petal' for the dissipation curve
23.04.2018 | Lobachevsky University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Structured light and nanomaterials open new ways to tailor light at the nanoscale

23.04.2018 | Physics and Astronomy

On the shape of the 'petal' for the dissipation curve

23.04.2018 | Physics and Astronomy

Clean and Efficient – Fraunhofer ISE Presents Hydrogen Technologies at the HANNOVER MESSE 2018

23.04.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>