Navigation Links
Small animal imaging facility is big boon to research
Date:8/30/2007

When powerful magnets line up the bodys protons before radiofrequency waves can grab their attention away, its called spin physics.

When signals generated by the movement are mathematically transformed into dramatic images of hearts, lungs and other organs its called a magnetic resonance image. Protons normally would be pointing in many different directions, says Dr. Tom Hu, director of the Small Animal Imaging Program at the Medical College of Georgia. But if you put an object in the MRI, the magnet will line up the protons and what that does is generate the original, steady state. Then, by applying different radio frequencies, pretty much like what you do with a car antenna, you can pursue radio frequencies to perturb the system and you pretty much listen to it.

When Dr. Hu, a biochemist and biophysicist, tunes in he sees how calcium moves in and out of heart cells as the heart contracts and relaxes and how that movement doesnt work so well in heart failure, a condition resulting in oversized hearts with difficulty beating.

Hes looking at whether the metallic manganese ion, which can travel in the same circles as calcium, can enhance the signal and subsequent images he gets of how calcium cant get back into cells after a heart attack. Once its disturbed, the cells die and the myocardium dies and you have scar formation, says Dr. Hu whose ultimate goals include better ways to diagnose and treat heart failure, an increasingly common problem in the United States where improved cardiac treatment means many people are living with their heart disease. Not only can you look at a living organ, you can also study the molecular aspects of this like the calcium ion, says Dr. Hu who came to MCG in 2005 to start the Small Imaging Program in support of research initiatives, such as his, that have clinical promise.

The MRI that is the programs centerpiece looks like the human version except the cylinder the patient lies in is obviously much smaller. However it has a stronger magnet than typical clinical grade units primarily because the organs of interest are so much smaller, says Dr. Nathan Yanasak, magnetic resonance scientist.

Many standard MRIs are 1.5 Tesla and high-end clinical units are 3 Tesla, a measure of the density and intensity of a magnetic field. MCGs small animal MRI is 7 Tesla, not the strongest magnet available for research but one that enables good quality images of small organs which are comparable to those obtained by clinical machines. Its pretty close to clinical grade, says Dr. Yanasak. But since you are scanning something smaller you need a larger field of strength to get the animal images to look like a human image, he says. The smallest heart theyve imaged, for example, is that of a 3-gram mice (thats a .105-ounce mouse). It is better resolution in the sense that you have to have better resolution to see a brain this big, Dr. Yanasak says, holding his fingers very close together.

The textbook answer for why scientists need high-tech imaging studies" They are noninvasive, says Dr. Hu, which obviously makes them excellent clinical tools as well. If you have an animal disease model, for pretty much any noninvasive technique, the advantage is it reduces animal use tremendously, he says.

Like physicians do with patients, basic scientists now use technology to help monitor disease progression over time and even to see if treatments work. In his own work, for example, Dr. Hu watches development of heart failure by monitoring changes in calcium dynamic and heart structure.

Newer technology, on loan to the facility from Xenogen Corp, part of Caliber Life Sciences Corp., has enabled the lab to throw genetic expression into the mix. The optical scanning system uses luciferase, the same enzyme fireflies use to glow, to identify gene expression.

"If you combine (luciferase) with certain genes and the genes are expressed, they glow, says Dr. Hu. For example, after a heart attack, you can look and see if certain genes are up-regulated, such as inflammatory genes. Now we take the same animal model back to the MRI machine and track how many cells have moved to the site of injury. So, we can combine the information and say, okay, potentially those cells that have been mobilized are due to the gene expression. We can try and link cause and effect so it becomes more of a valuable image, says Dr. Hu. Right now he and Dr. Yanasak are fine-tuning how to make MRI and optical scanning work optimally together and how to also quantify gene expression.

The number of MCG scientists using the facility is significant and growing, says its director. Dr. Adviye Ergul, for example, is looking at blood flow in the brain of her diabetes model and Dr. William Hill is looking at stroke event and recovery.

We are very open to any interesting ideas that generate interesting scientific data or grant funding opportunities, says Dr. Hu. Goals include becoming an MCG core laboratory facility and adding a small animal PET scanner and ultrasound.


'/>"/>
Contact: Toni Baker
tbaker@mcg.edu
706-721-4421
Medical College of Georgia
Source:Eurekalert

Related biology news :

1. Stopping smallpox in its tracks: A new anti-viral approach
2. Small species back-up giant marsupial climate change extinction claim
3. New World founders small in number
4. Secret of smallpoxs success may lead to bioterror cure
5. Circulating stem cells play small role in lung repair
6. Small worm yields big clue on muscle receptor action
7. No small feat: First ever gene therapy success for muscular dystrophy achieved
8. LIAI scientists make major finding on potential smallpox treatment
9. Researchers develop new testing methods for potential monkeypox or smallpox outbreak
10. Solexa and collaborating scientists illuminate the small RNA component of the transcriptome
11. Delaware scientists make significant advance in study of small RNAs
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/29/2016)... Nov. 29, 2016   Neurotechnology , ... object recognition technologies, today released FingerCell 3.0, ... recognition solutions that run on low-power, low-memory ... using less than 128KB of memory, enabling ... that have limited on-board resources, such as: ...
(Date:11/24/2016)... 2016 Cercacor today introduced Ember TM ... non-invasively measure hemoglobin, Oxygen Content, Oxygen Saturation, ... Rate in approximately 30 seconds. Smaller than a smartphone, ... access to key data about their bodies to help ... Hemoglobin carries oxygen to muscles. When ...
(Date:11/21/2016)... 21, 2016   Neurotechnology , a provider ... today announced that the MegaMatcher On Card fingerprint ... for the NIST Minutiae Interoperability Exchange (MINEX) ... mandatory steps of the evaluation protocol. ... test of fingerprint templates used to establish compliance ...
Breaking Biology News(10 mins):
(Date:12/9/2016)... New York , December 9, 2016 ... states that the top five players in the  Global ... 62.7% in the overall market in 2015. Players such ... Perkin Elmer have remained dominant in the global market ... efforts to ensure product innovation. Product upgrades and timely ...
(Date:12/8/2016)... 8, 2016  The Board of Directors of the ... Western Pennsylvania,s only pure life sciences investment ... with the succession plan developed by the Nominating and ... James (Jim) F. Jordan is selected to ... John W. Manzetti , who is elected to the ...
(Date:12/8/2016)... , December 8, 2016 AskLinkerReports.com ... comprehensive analysis, titled Global Amyloglucosidase Industry 2016 Market Research Report. ... application, and industry chain overview are all covered in the ... analysis, and investment return analysis of the Amyloglucosidase industry. ... , , ...
(Date:12/8/2016)... (PRWEB) , ... December 08, 2016 , ... ... the FrontPanel SDK that provide essential device-to-computer interconnect using USB or PCI Express, ... require FrontPanel support. The FOMD-ACV-A4 is a small, thin, SODIMM-style module that fits ...
Breaking Biology Technology: