Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Brain imaging techniques sharpen focus on Alzheimer’s

20.07.2004


Recent advances in brain imaging may allow very early diagnosis of Alzheimer’s and other dementias, and improved assessment of treatment effectiveness



Imaging techniques such as PET and MRI are near to becoming useful in diagnosing Alzheimer’s disease earlier and distinguishing it from other types of dementia, according to research reported today at the 9th International Conference on Alzheimer’s Disease and Related Disorders (ICAD), presented by the Alzheimer’s Association.

For example, one study at the conference reports the latest data on a new PET technology that allows researchers to see – for the first time – accumulations of the abnormal protein tau in the brains of people with a rare form of dementia.


"Having the ability to observe the damage and progression of Alzheimer’s in the living brain will have a profound impact on how we diagnose the disease, as well as how we gauge the effectiveness of current medical treatments and those in development," said William Thies, Ph.D., vice president of Medical & Scientific Affairs for the Alzheimer’s Association.

Researchers View the Early Stages of Alzheimer’s In the Brain

Advances in positron emission tomography (PET) allow researchers to evaluate brain changes of people whose mild cognitive impairment (MCI) may represent the early stages of Alzheimer’s. William E. Klunk, M.D., Ph.D., and colleagues at the University of Pittsburgh have recently developed a compound known as Pittsburgh Compound-B (PIB) – visible on PET scans – that sticks to abnormal clumps of protein in the brain called amyloid plaques. Plaques and other abnormal protein aggregates called tangles are the hallmarks of Alzheimer’s disease. The main component of the plaques, a toxic protein fragment called beta-amyloid, is a primary suspect in the death of brain cells in Alzheimer’s.

Klunk and colleagues presented PET scan data from a preliminary study of five people with MCI. They found that the subjects fall into two distinct groups. One group has evidence of amyloid deposition that is indistinguishable from normal controls, and the other group has evidence of amyloid deposition that is indistinguishable from Alzheimer’s disease patients.

Some people with MCI progress to Alzheimer’s while others do not. It may be that levels of amyloid in the brain are related to who develops the disease. The researchers will attempt to replicate these results in a much larger study.

"Amyloid imaging with PET may become useful for predicting which people with MCI will progress to Alzheimer’s in the near future. The technology might also help to determine the effectiveness of anti-amyloid therapies in people with MCI and Alzheimer’s," said Klunk.

First Visualization of "Tangles" in Frontotemporal Dementia

Another PET development allows researchers to see–for the first time–accumulations of the abnormal protein tau in the brains of people with a rare form of dementia. Gary Small, M.D., of the University of California, Los Angeles, and his colleagues have developed a PET compound, [F-18]FDDNP, that "sticks" both to amyloid plaques and the tangles of abnormal tau protein in the brains of Alzheimer’s patients. In their report at ICAD, the researchers used this new compound to map the tangles also found in frontotemporal dementia (FTD), a rare disorder with symptoms similar to Alzheimer’s.

"We believe this is the first time tau accumulation has been visualized in living patients," said Small. "The new technique may help us better differentiate between Alzheimer’s and other forms of dementia – leading to more effective treatments."

The researchers compared PET scans of people with FTD and Alzheimer’s. They found very different distributions of protein accumulations. The different patterns may serve as a useful tool to differentiate Alzheimer and FTD patients. The researchers hope the technique also can be used to monitor the effectiveness of drugs to clear abnormal proteins such as tau from the brain.

MRI Shows Ability to Distinguish Possible Early Alzheimer’s and Effects of Treatment

A combination of anatomic and functional magnetic resonance imaging (MRI), which can detect brain abnormalities in people with Alzheimer’s disease, may also be able to identify brain changes in people who complain of cognitive deficits but do not meet the criteria for a diagnosis of MCI or Alzheimer’s.

Andrew J. Saykin, Psy.D., of Dartmouth Medical School, Lebanon, New Hampshire, leads a team following the progress of 90 older adults as they age. At the outset of the study, 30 of the participants reported no significant declines in memory or other mental functions, while another 30 had cognitive deficits that warranted a diagnosis of MCI. The remaining 30 participants – termed the cognitive complaint group – had perceived deficits in memory and other mental functions that did not reach the threshold for MCI diagnosis and could not be explained by depression or other health problems. The researchers are employing repeat MRI scans to track changes in gray matter and brain activity during memory task performance and comparing the three groups over time. However, even in the baseline study, a surprising parallel was noted between the cognitive complaint and MCI groups.

"The pattern of reduction of gray matter and brain activity in the older adults who complained of cognitive deficits was almost identical to that seen in patients with MCI, suggesting that many of these people may be in the earliest stages of Alzheimer’s," said Saykin. "Early detection will be essential as new preventative and treatment strategies become available."

The 9th International Conference on Alzheimer’s Disease and Related Disorders (ICAD), presented by the Alzheimer’s Association, is the largest gathering of Alzheimer researchers in history. More than 4,500 scientists from around the world will present and discuss the findings of 2,000 studies showcasing the newest treatment advances in Alzheimer’s disease and steps toward prevention. ICAD will be held July 17-22, 2004, at the Pennsylvania Convention Center in Philadelphia, Pennsylvania.

| EurekAlert!
Further information:
http://www.alz.org

More articles from Health and Medicine:

nachricht Researchers identify new way to unmask melanoma cells to the immune system
17.01.2018 | Duke University Medical Center

nachricht Study advances gene therapy for glaucoma
17.01.2018 | University of Wisconsin-Madison

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: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

More genes are active in high-performance maize

19.01.2018 | Life Sciences

How plants see light

19.01.2018 | Life Sciences

Artificial agent designs quantum experiments

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>