(Press-News.org) Researchers from Banner Alzheimer's Institute (BAI) have developed a new brain image analysis method to better track the progression of beta-amyloid plaque deposition, a characteristic brain abnormality in Alzheimer's disease, according to a study published in the March issue of the Journal of Nuclear Medicine. Investigators also believe this new approach may make it easier to evaluate investigational anti-amyloid treatments in clinical trials.
During the last decade, researchers have been using positron emission topography (PET) to assess amyloid plaque deposition in patients with clinical symptoms of Alzheimer's and in cognitively normal persons at risk for the disease. They also have been using it to assess the ability of investigational treatments to slow the further accumulation of amyloid or remove plaques that already exist.
Amyloid plaques are typically measured by comparing measurements from the cerebral cortex, where plaques accumulate most, to a reference region that is relatively spared, like the cerebellum. Unfortunately, when plaques are measured this way, there can be substantial variability from one scan to the next, due at least in part to technical reasons.
BAI investigators have shown that the use of another reference region--cerebral white matter--can greatly reduce this variability. These findings are consistent with results reported in the same journal issue by Landau, et al., who similarly concluded that cerebral white matter permits better tracking of amyloid deposition. Findings from both studies support the use of a white matter reference region to improve the power to track progressive amyloid changes and evaluate amyloid-modifying treatments using amyloid PET.
"We and other researchers have been interested in finding better ways to track the brain changes associated with Alzheimer's disease and evaluate investigational treatments in the most rapid and cost-effective way," said Eric Reiman, M.D., the study's senior researcher and executive director of the Banner Alzheimer's Institute. "We hope that this new image analysis technique will help in that endeavor."
Kewei Chen, Ph.D., the study's lead researcher, and his team analyzed baseline and 24-month follow-up florbetapir (a compound that binds to beta-amyloids) PET scans in 332 participants of the Alzheimer's Disease Neuroimaging Initiative (ADNI), a public-private partnership working to advance Alzheimer's research. Of the 332 participants, 31 had clinical diagnoses of probable Alzheimer's dementia, 187 had diagnoses of mild cognitive impairment and 114 were cognitively normal older adults.
The team compared the uptake of the amyloid PET ligand florbetapir in the cerebral cortex to its uptake in three different reference regions--cerebral white matter, pons and cerebellum. This calculation, known as a standard-uptake-value ratio (SUVR), allowed investigators to determine which of the reference regions provided the best tracking of amyloids over the course of two years.
Chen and colleagues found that using the cerebral white matter reference region resulted in more accurate tracking of SUVRs among patients with probable Alzheimer's, patients with mild cognitive impairment, and those older adults who, although cognitively normal, were found to be amyloid positive at their baseline visit. The cerebral-to-cerebral white matter SUVR increases also correlated with poorer scores on study participants' neurocognitive tests, whereas SUVRs from the other reference regions failed to demonstrate this pattern.
Compared to the pontine and cerebellar reference regions, the cerebral white matter reference region also resulted in less variability in repeated florbetapir SUVRs readings (e.g., less paradoxical decreases) over time in patients with probable Alzheimer's.
"The white matter reference region not only improved the ability to track SUVR increases, it permitted us to find close associations between SUVR increases and clinical declines in the overall subject group," said Chen. "While additional studies are needed to demonstrate the generalizability of this approach to other amyloid PET ligands, we are excited about its potential to help in the scientific study of Alzheimer's disease and the evaluation of amyloid-modifying treatments."
INFORMATION:
About Banner Alzheimer's Institute
Through its research and care, Banner Alzheimer's Institute (BAI) is dedicated to the goal of ending Alzheimer's disease without losing another generation. It is helping to launch a new era of Alzheimer's research--treatment and prevention at the pre-symptomatic stage--and to establish a new comprehensive model of care. Established in 2006 by Banner Health, one of the country's largest nonprofit health care systems, BAI has a three-fold focus: to conduct revolutionary studies in the detection, treatment and prevention of Alzheimer's; to set a national standard of patient and family care; and to forge scientific collaborations that bring together institutions and disciplines internationally. For more information, visit banneralz.org.
A psychology study from The University of Texas at Austin sheds new light on today's standards of beauty, attributing modern men's preferences for women with a curvy backside to prehistoric influences.
The study, published online in Evolution and Human Behavior, investigated men's mate preference for women with a "theoretically optimal angle of lumbar curvature," a 45.5 degree curve from back to buttocks allowing ancestral women to better support, provide for, and carry out multiple pregnancies.
"What's fascinating about this research is that it is yet another scientific ...
WASHINGTON, March 19, 2015 -- It's a simple claim made on thousands of personal care products for adults and kids: hypoallergenic. But what does that actually mean? Turns out, it can mean whatever manufacturers want it to mean, and that can leave you feeling itchy. Speaking of Chemistry is back this week with Sophia Cai explaining why "hypoallergenic" isn't really a thing. Check it out here: http://youtu.be/lXh8bnqMOZs.
Speaking of Chemistry is a production of Chemical & Engineering News, a weekly magazine of the American Chemical Society. The program features fascinating, ...
The Canadian research community on high-temperature superconductivity continues to lead this exciting scientific field with groundbreaking results coming hot on the heels of big theoretical questions.
The latest breakthrough, which will be published March 20 in Science, answers a key question on the microscopic electronic structure of cuprate superconductors, the most celebrated material family in our quest for true room-temperature superconductivity.
This result is the product of a longstanding close collaboration between the University of British Columbia Quantum ...
Some 2.5 million years ago, early humans survived on a paltry diet of plants. As the human brain expanded, however, it required more substantial nourishment - namely fat and meat - to sustain it. This drove prehistoric man, who lacked the requisite claws and sharp teeth of carnivores, to develop the skills and tools necessary to hunt animals and butcher fat and meat from large carcasses.
Among elephant remains some 500,000 years old at a Lower Paleolithic site in Revadim, Israel, Prof. Ran Barkai and his graduate students Natasha Solodenko and Andrea Zupanchich of Tel ...
DENVER, March 23, 2015 -- Since HIV emerged in the '80s, drug "cocktails" transformed the deadly disease into a manageable one. But the virus is adept at developing resistance to drugs, and treatment regimens require tweaking that can be costly. Now scientists at the 249th National Meeting & Exposition of the American Chemical Society (ACS) are announcing new progress toward affordable drugs that could potentially thwart the virus's ability to resist them.
ACS, the world's largest scientific society, is holding the meeting here through Thursday. It features nearly 11,000 ...
Washington, D.C.--To combat global climate change caused by greenhouse gases, alternative energy sources and other types of environmental recourse actions are needed. There are a variety of proposals that involve using vertical ocean pipes to move seawater to the surface from the depths in order to reap different potential climate benefits. A new study from a group of Carnegie scientists determines that these types of pipes could actually increase global warming quite drastically. It is published in Environmental Research Letters.
One proposed strategy--called Ocean ...
What if there were a pill that made you more compassionate and more likely to give spare change to someone less fortunate? UC Berkeley scientists have taken a big step in that direction.
A new study by UC Berkeley and UC San Francisco researchers finds that giving a drug that changes the neurochemical balance in the prefrontal cortex of the brain causes a greater willingness to engage in prosocial behaviors, such as ensuring that resources are divided more equally.
The researchers also say that future research may lead to a better understanding of the interaction between ...
URBANA, Ill. - Over the last several decades there have been substantial yield improvements in soybean. Because of new varieties and new agronomic practices, the yield potential in soybean is higher now than ever before. But a lack of updated information on the nutritional needs of soybean crops may be limiting the crop's potential.
Researchers from the University of Illinois Crop Physiology Laboratory led by Fred Below have recently provided an updated set of nutrition needs for soybean, identifying exactly which nutrients the plant needs, when those nutrients are accumulated ...
Acne, a scourge of adolescence, may be about to meet its ultra high-tech match. By using a combination of ultrasound, gold-covered particles and lasers, researchers from UC Santa Barbara and the private medical device company Sebacia have developed a targeted therapy that could potentially lessen the frequency and intensity of breakouts, relieving acne sufferers the discomfort and stress of dealing with severe and recurring pimples.
"Through this unique collaboration, we have essentially established the foundation of a novel therapy," said Samir Mitragotri, professor ...
Our eyes are drawn to several dimensions of an object--such as color, texture, and luminance--even when we need to focus on only one of them, researchers at New York University and the University of Pennsylvania have found. The study, which appears in the journal Current Biology, points to the ability of our visual system to integrate multiple components of an item while underscoring the difficulty we have in focusing on a particular aspect of it.
"Even when we want and need to focus on one dimension of things we come across every day, such as the texture of your cat's ...
