Posts tagged science
Articles and news from the latest research reports.
Astrocytes Control the Generation of New Neurons from Neural Stem Cells
August 24th, 2012
Researchers from the Laboratory of astrocyte biology and CNS regeneration headed by Prof. Milos Pekny just published a research article in a prestigious journal Stem Cells on the molecular mechanism that controls generation of new neurons in the brain.
Astrocytes are cells that have many functions in the central nervous system, such as the control of neuronal synapses, blood flow, or the brain’s response to neurotrauma or stroke.
Reduces brain tissue damage
Prof. Pekny’s laboratory together with collaborators have earlier demonstrated that astrocytes reduce the brain tissue damage after stroke and that the integration of transplanted neural stem cells can be largely improved by modulating the activity of astrocytes.
Generation of new neurons
In their current study, the Sahlgrenska Academy researchers show how astrocytes control the generation of new neurons in the brain. An important contribution to this project came from Åbo Academy, one of Sahlgrenska’s traditional collaborative partners.
“In the brain, astrocytes control how many new neurons are formed from neural stem cells and survive to integrate into the existing neuronal networks. Astrocytes do this by secreting specific molecules but also by much less understood direct cell-cell interactions with stem cells”, says Prof. Milos Pekny.
Image shows GFAP stained cortex from a TgAPP mouse showing activated astrocytes from a different study.
Important regulator
“Astrocytes are in physical contact with neural stem cells and we have shown that they signal through the Notch pathway to stem cells to keep the birth rate of new neurons low. We have also shown that the intermediate filament system of astrocytes is an important regulator of this process. It seems that astrocyte intermediate filaments can be used as a target to increase the birthrate of new neurons.”
Target for future therapies
“We are starting to understand some of the cellular and molecular mechanisms behind the control of neurogenesis. Neurogenesis is one of the components of brain plasticity, which plays a role in the learning process as well as in the recovery after brain injury or stroke. This work helps us to understand how plasticity and regenerative response can be therapeutically promoted in the future”, says Prof. Milos Pekny.
Source: Neuroscience News
Simple eye test could diagnose Alzheimer’s
The researchers from Lancaster University have found that those with the degenerative brain disease have difficulty with one particular test. They also found that the inability to carry out the tests in those who had already been diagnosed with Alzheimer’s was linked to lower memory function.
Photo: ALAMY
Dr Trevor Crawford said the latest results were potentially exciting. They showed, for the first time, a physical connection with the memory impairment that so often is the first noticeable symptom in Alzheimer’s.
Dr Crawford, of the department of Psychology and the Centre for Ageing Research, Lancaster University, said: “The diagnosis of Alzheimer’s disease is currently heavily dependent on the results of a series of lengthy neuropsychological tests.
"However, patients with a dementia often find that these tests are difficult to complete due to a lack of clear understanding and lapse in their attention or motivation.
"Over the last 10 years, researchers in laboratories around the world have been working on an alternative approach based on the brain’s control of the movements of the eye as a tool for investigating cognitive abilities, such as attention, cognitive inhibition and memory."
During the study, 18 patients with Alzheimer’s disease, 25 patients with Parkinson’s disease, 17 healthy young people and 18 healthy older people were asked to follow the movements of light on a computer monitor. In some instances they were asked to look away from the light. Detailed eye–tracking measurements showed stark contrasts in results.
Patients with Alzheimer’s made errors on the task when they were asked to look away from the light. They were unable correct those errors, despite being able to respond normally when they were asked to look towards the light.
These uncorrected errors were 10 times more frequent in the Alzheimers’ patients than the control groups. Researchers also measured memory function among those Alzheimer’s patients who found the test difficult and were able to show a clear correlation with lower memory function. Dr Crawford added: “The light tracking test could play a vital role in the diagnosis of Alzheimer’s.”
(Source: telegraph.co.uk)
Women with Alzheimer’s show worse mental deterioration than men with the disease, even when at the same stage of the condition, according to researchers from the University of Hertfordshire.
In the paper published in the Journal of Clinical and Experimental Neuropsychology, the researchers discovered that men with Alzheimer’s consistently and significantly performed better than women with the disease across the five cognitive areas they examined. Most remarkably, the verbal skills of women with Alzheimer’s are worse when compared to men with the disease, which is a striking difference to the profile for the healthy population where females have a distinct advantage.
The man who holds the record for the world’s lowest voice can hit notes so low that only animals as massive as elephants are able to hear them. U.S. singer Tim Storms can reach notes as low as G-7 (0.189Hz). That’s a remarkable 8 octaves below the lowest G on a piano. So low, in fact, that even Storms himself cannot hear it.
A team of University of Minnesota biomedical engineers and researchers from Mayo Clinic published a groundbreaking study that outlines how a new type of non-invasive brain scan taken immediately after a seizure gives additional insight into possible causes and treatments for epilepsy patients. The new findings could specifically benefit millions of people who are unable to control their epilepsy with medication.
The research was published online in Brain, a leading international journal of neurology.
Professor Bin He discusses his research on a new type of non-invasive brain scan that gives additional insight into possible causes and treatments for epilepsy patients.
Research pinpoints brain’s ‘Gullibility’ center
August 24, 2012 By Barbara Bronson Gray
(HealthDay)—Whether it’s an email from an unknown gentleman on another continent pleading for money or a financial scammer selling a promising penny stock, the young and old tend to be more easily duped than middle-aged people.
Changes in this region could explain why seniors, children are less doubting.
Now, researchers have pinpointed the area of the brain responsible for this gullibility and have theorized why it makes children, teens and seniors less likely to doubt.
The ventromedial area of the prefrontal cortex of the brain—a softball-sized lobe in the front of your head, just above your eyes—appears to be responsible for allowing you to pause after hearing or reading something and consider whether it’s true, according to a study published recently in the journal Frontiers in Neuroscience.
Most experimental cancer drugs never make it to market because they don’t help enough people in early clinical trials. But even in “failed” drug trials, researchers may find that a few patients see their tumors shrink dramatically. Since it’s not clear why some respond but most don’t, researchers typically shake their heads and move on. But researchers today report that by sequencing the entire genome of one outlier patient’s tumor, they learned why her cancer disappeared when she took an experimental drug that didn’t help others. That drug now has a new lease on life for this cancer, and such testing may help revive other cancer drugs that showed promise in lab studies but initially failed in clinical testing.
Early fruits of the collaboration between the Genome 10K project and Beijing Genomics Institute (BGI) to sequence 100 vertebrate species have resulted in the sequencing and release of the genome of one of naturalist Charles Darwin’s Galápagos finches, the medium ground finch Geospiza fortis.
This finch genome, the first of the BGI-Genome 10K collaboration to be made available through the UCSC Genome Browser, represents both a scientific and a symbolic advancement, according to Erich Jarvis, Duke University associate professor who studies the neurobiology of vocal learning in songbirds.
Endemic to the subtropical or tropical dry forests and shrublands of the Galápagos Islands this species evolves rapidly in response to environmental changes. ”These finches are of great historical significance, but when Darwin first studied these birds, he was unlikely to have envisioned how this species would become a perfect model to study evolution in action,” said Goujie Zhang, BGI’s associate director of research. “Having the reference genome of this species has opened the door for carrying out studies that can look at real-time evolutionary changes on a genomic level of all of these enigmatic species.”
(Image by: Petr Baum)
The co-founder of Alcoholics Anonymous (AA) believed LSD could be used to cure alcoholics and credited the drug with helping his own recovery from often debilitating depression, according to new research.
About 20 years after setting up the Ohio-based sobriety movement in 1935, Bill Wilson came to believe that LSD could help “cynical alcoholics” achieve a “spiritual awakening” and start on the path to recovery.
The discovery that Wilson considered using the drug as an aid to recovery for addicts was made by Don Lattin, author of a book to be published in October by the University of California Press, entitled Distilled Spirits.
Language, Emotion and Well-Being Explored
ScienceDaily (Aug. 23, 2012) — We use language every day to express our emotions, but can this language actually affect what and how we feel? Two new studies from Psychological Science, a journal of the Association for Psychological Science, explore the ways in which the interaction between language and emotion influences our well-being.
Putting Feelings into Words Can Help Us Cope with Scary Situations
Katharina Kircanski and colleagues at the University of California, Los Angeles investigated whether verbalizing a current emotional experience, even when that experience is negative, might be an effective method for treating for people with spider phobias. In an exposure therapy study, participants were split into different experimental groups and they were instructed to approach a spider over several consecutive days.
One group was told to put their feelings into words by describing their negative emotions about approaching the spider. Another group was asked to ‘reappraise’ the situation by describing the spider using emotionally neutral words. A third group was told to talk about an unrelated topic (things in their home) and a fourth group received no intervention. Participants who put their negative feelings into words were most effective at lowering their levels of physiological arousal. They were also slightly more willing to approach the spider. The findings suggest that talking about your feelings — even if they’re negative — may help you to cope with a scary situation.
Unlocking Past Emotion: The Verbs We Use Can Affect Mood and Happiness
Our memory for events is influenced by the language we use. When we talk about a past occurrence, we can describe it as ongoing (I was running) or already completed (I ran). To investigate whether using these different wordings might affect our mood and overall happiness, Will Hart of the University of Alabama conducted four experiments in which participants either recalled or experienced a positive, negative, or neutral event. They found that people who described a positive event with words that suggested it was ongoing felt more positive. And when they described a negative event in the same way, they felt more negative.
The authors conclude that one potential way to improve mood could be to talk about negative past events as something that already happened as opposed to something that was happening.
Source: Science Daily