Alzheimer's disease is associated with abnormalities in the vast network of blood vessels in the brain, but it hasn’t been known how this affects cognition. A study has now shown that a blood-clotting protein called fibrinogen plays a part.
The study found that fibrinogen, after leaking from the blood into the brain, activates the brain's immune cells and triggers them to destroy synapses, which are critical for neuronal communication.
Perivascular spaces are fluid-filled spaces around the cerebral small vessels, commonly seen on brain scans in older adults. They have been thought to be harmless, but a new study challenges this belief.
A large, long-running Finnish study looking at the dietary habits of 2,497 men aged 42-60 has found that a high intake of dietary cholesterol was not associated with the risk of dementia or Alzheimer's disease, even among carriers of the ‘Alzheimer’s gene’ APOE4.
Previous research has found that the effect of dietary cholesterol on serum cholesterol levels is more visible in carriers of APOE4. In Finland, the prevalence of the APOE4 gene variant is exceptionally high and approximately a third of the population are carriers.
DNA data from more than 48,000 patients and 139,000 healthy controls from four different ethnic groups has identified seven new genetic regions associated with type 2 diabetes.
http://www.eurekalert.org/pub_releases/2014-02/uoo-sng020714.php
A Swedish study has found that those who ate poor breakfasts as year 9 students had a higher incidence of metabolic syndrome 27 years later, compared with those who ate more substantial breakfasts.
http://www.eurekalert.org/pub_releases/2014-01/uu-pbi012914.php
Analysis of 5715 cases from the National Alzheimer's Coordinating Center (NACC) database has found that nearly 80% of more than 4600 Alzheimer's disease patients showed some degree of vascular pathology, compared with 67% of the controls, and 66% in the Parkinson's group. The link was especially strong for younger patients with Alzheimer’s.
Analysis of data from 237 patients with mild cognitive impairment (mean age 79.9) has found that, compared to those carrying the ‘normal’ ApoE3 gene (the most common variant of the ApoE gene), the ApoE4 carriers showed markedly greater rates of shrinkage in 13 of 15 brain regions thought to be key components of the brain networks disrupted in Alzheimer’s.
http://www.eurekalert.org/pub_releases/2014-01/rson-gva010714.php
Because this is such a persistent myth, I thought I should briefly report on this massive study that should hopefully put an end to this myth once and for all (I wish! Myths are not so easily squashed.)
This study used data from 377,000 U.S. high school students, and, agreeing with a previous large study, found that first-borns have a one IQ point advantage over later-born siblings, but while statistically significant, this is a difference of no practical significance.
Brain imaging while 11 individuals with traumatic brain injury and 15 healthy controls performed a working memory task has revealed that those with TBI showed greater connectivity between the hemispheres in the fronto-parietal regions (involved in working memory) and less organized flow of information from posterior to anterior parts.
The study used a new task, known as CapMan, which allows working memory capacity and the mental manipulation of information in working memory to be distinguished from each other.
Following on from a previous study showing that such a virtual supermarket game administered by a trained professional can detect MCI, a small study used a modified Virtual SuperMarket Remote Assessment Routine (VSM-RAR) that was self-administered by the patient at home on their own, for a period of one month.
Using the average score over 20 assessments, the game correctly diagnosed MCI 91.8% of the time, a level of diagnostic accuracy similar to the most accurate standardized neuropsychological tests.