Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New dye could offer early test for Alzheimer’s

26.08.2005


MIT technique is noninvasive



MIT scientists have developed a new dye that could offer noninvasive early diagnosis of Alzheimer’s disease, a discovery that could aid in monitoring the progression of the disease and in studying the efficacy of new treatments to stop it.
The work will be published in the Aug. 26 issue of Angewandte Chemie.

Today, doctors can only make a definitive diagnosis of Alzheimer’s-currently the fourth-leading cause of death in the United States-through a postmortem autopsy of the brain. "Before you can cure Alzheimer’s, you have to be able to diagnose it and monitor its progress very precisely," said Timothy Swager, leader of the work and a professor in MIT’s Department of Chemistry. "Otherwise it’s hard to know whether a new treatment is working or not."



To that end, Swager and postdoctoral associate Evgueni Nesterov, also from the MIT Department of Chemistry, worked with researchers at Massachusetts General Hospital and the University of Pittsburgh to develop a contrast agent that would first bind to the protein deposits, or plaques, in the brain that cause Alzheimer’s, and then fluoresce when exposed to radiation in the near-infrared range. The new dye could allow direct imaging of Alzheimer’s plaques through a patient’s skull.

Some of the first noninvasive techniques for diagnosing Alzheimer’s involved agents labeled with radioactive elements that could enter the brain and target disease plaque for imaging with positron emission tomography (PET). However, these methods were expensive and limited by the short working lifetime of the labeled agents.

Swager and colleagues developed the new dye, called NIAD-4, through a targeted design process based on a set of specific requirements, including the ability to enter the brain rapidly upon injection, bind to amyloid plaques, absorb and fluoresce radiation in the right spectral range, and provide sharp contrast between the plaques and the surrounding tissue. The compound provided clear visual images of amyloid brain plaques in living mice with specially prepared cranial windows.

To make the technique truly noninvasive, scientists must further refine the dye so it fluoresces at a slightly longer wavelength, closer to the infrared region. Light in the near-IR range can penetrate living tissue well enough to make brain structures visible. Swager likens the effect to the translucence produced when one holds a red laser pointer against the side of a finger.

"This procedure could be done in a chamber with a photodetector and a bunch of lasers, and it would be painless," he said, adding that infrared fluorescence and other optical techniques will lead to a whole new class of noninvasive medical diagnostics. Swager says fluorescing dyes like NIAD-4 could be ready for clinical trials in the near future.

"What we have is a dye that lights up when it binds to amyloids that form in the brains of people with Alzheimer’s. It’s a completely new transduction scheme-a way of translating a physical or chemical event that’s invisible to the naked eye, into a recognizable signal. Further wavelength adjustments in these dyes will allow us to perform in vivo analysis through human tissue."

The new dye was developed as part of a broader effort in sensing technology at MIT’s Institute for Soldier Nanotechnologies. In addition to its applications as a medical diagnostic, Swager says fluorescing dyes like NIAD-4 could work as signals in a wide variety of sensing schemes.

Eve Downing | EurekAlert!
Further information:
http://www.mit.edu

More articles from Health and Medicine:

nachricht Biofilm discovery suggests new way to prevent dangerous infections
23.05.2017 | University of Texas at Austin

nachricht Another reason to exercise: Burning bone fat -- a key to better bone health
19.05.2017 | University of North Carolina Health Care

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>