Posts tagged psychology
Articles and news from the latest research reports.
A study in mice conducted by researchers at Tufts University School of Medicine suggests that a woman’s risk of anxiety and dysfunctional social behavior may depend on the experiences of her parents, particularly fathers, when they were young.
The study, published online in Biological Psychiatry, suggests that stress caused by chronic social instability during youth contributes to epigenetic changes in sperm cells that can lead to psychiatric disorders in female offspring across multiple generations.
Fathers bequeath more mutations as they age
22 August 2012 by Ewen Callaway
Genome study may explain links between paternal age and conditions such as autism.
Older fathers’ sperm have more mutations — as do their children.
V. Peñafiel/Flickr/GETTY
In the 1930s, the pioneering geneticist J. B. S. Haldane noticed a peculiar inheritance pattern in families with long histories of haemophilia. The faulty mutation responsible for the blood-clotting disorder tended to arise on the X chromosomes that fathers passed to their daughters, rather than on those that mothers passed down. Haldane subsequently proposed that children inherit more mutations from their fathers than their mothers, although he acknowledged that “it is difficult to see how this could be proved or disproved for many years to come”.
(Source: nature.com)
A new UCLA study pinpoints uniquely human patterns of gene activity in the brain that could shed light on how we evolved differently than our closest relative. Published Aug. 22 in the advance online edition of Neuron, these genes’ identification could improve understanding of human brain diseases like autism and schizophrenia, as well as learning disorders and addictions.
(Image by Michael Nichols)
Using bioluminescent proteins from a jellyfish, a team of scientists has lit up the inside of a neuron, capturing spectacular video footage that shows the movement of proteins throughout the cell.
(Source: medicalxpress.com)
With his knack for knowing what stem cells want, Yoshiki Sasai has grown an eye and parts of a brain in a dish.
All it took to grow a retina, it turned out, were a few tweaks, such as a reduction in the concentration of growth factors and the addition of a standard cell-culture ingredient called Matrigel. The result closely mimics eye development in the embryo. By the sixth day in culture, the brain balls start sprouting balloon-like growths of retinal cells, which then collapse in on themselves to make the double-walled optic cups. Sasai’s team snip them off — “like taking an apple from a tree”, says Sasai — transfer them to a different culture and let them be. Two weeks later, the cups have formed all six layers of the retina, an architecture that resembles the eye of an 8-day-old mouse (which, at that age, is still blind). That the cells could drive themselves through this dramatic biomechanical process without surrounding tissues to support them stunned Sasai as much as anyone else. “When I saw it, I thought, ‘Oh my god.’ Shape, topology and size are all recapitulated,” he says. Carefully explaining the pun to come, he adds: “In English, when you are surprised, you say ‘eye-popping’ — so we really thought this was eye-popping.”
(Source: nature.com)
Researchers at the University of Iowa studied the brain of a patient with rare, severe damage to three regions long considered integral to self-awareness in humans (from left to right: the insular cortex, anterior cingulate cortex, and the medial prefrontal cortex). Based on the scans, the UI team believes self-awareness is a product of a diffuse patchwork of pathways in the brain rather than confined to specific areas.
Stem Cell Trial for Autism Launches in U.S.
August 21, 2012
Stem cell treatment could lower inflammation levels and demonstrate whether autism is an autoimmune disease
Image: Nature News
Families with autistic children must navigate a condition where questions outnumber the answers, and therapies remain sparse and largely ineffective. A clinical trial being conducted by the Sutter Neuroscience Institute in Sacramento, California to address this situation began recruiting participants today for a highly experimental stem cell therapy for autism. The institute plans to find 30 autistic children between ages 2 and 7 with cord blood banked at the privately-run Cord Blood Registry, located about 100 miles west of the institute. Already one other clinical trial, with 37 total participants between ages 3 and 12 years old, has been completed in China. The researchers affiliated with Beike Biotechnology in Shenzhen, the firm that sponsored the study, have not yet published any papers from that the trial, which used stem cells from donated cord blood. Mexican researchers are currently recruiting kids for yet another type of autism stem cell trial that will harvest cells from the participant’s fat tissue.
But for each of these officially registered trials, many more undocumented stem cell therapy treatments take place for clients who are willing to pay enough. “Our research is important because many people are going to foreign countries and spending a lot of money on therapy that may not be valid,” says Michael Chez, a pediatric neurologist and lead investigator of the study at Sutter.
A major difference between the Sutter trial and those in China is that his will use the child’s own stem cells, rather than those from a donor. Chez hypothesizes that one way autologous stem cell infusion might work is by reducing inflammation within the body’s immune system. This would answer previous research that suggests that autism may be an autoimmune disease. “One of our exploratory goals will be to look at inflammatory markers in cells,” he says.
The study’s primary goal, however, will be assessing changes in patients’ speaking and understanding of vocabulary. For each individual, researchers will create a baseline benchmark that establishes current skill levels. The group will be evenly divided, with one initially receiving an infusion of their own, unmodified cord blood stem cells and the other a placebo treatment of saline injection. Six months later, all of the children will be tested on their ability to comprehend and form words. The groups will then be switched. In the course of the 13-month-long study, both groups will receive only one stem cell therapy infusion.
Not all stem cell scientists who study neurodevelopmental diseases are ready to invest great hope that the autism stem cell trial will succeed. “I wish I could tell you I’m optimistic about the end results,” says James Carroll, a pediatric neurologist at the Georgia Health Sciences University in Augusta who began a clinical trial two years ago to better understand how stem cell therapy affects patients with cerebral palsy. “But so far we have not seen any kind of miraculous recovery in our cerebral palsy patients. I would be delighted if that changes.”
Members in the stem cell therapy patient community think Chez will have no shortage of volunteers for the trial. Jeremy Lowey, who lives in Sacramento and has struggled with a rare condition known as non-verbal learning disorder, arranged for his own stem cell therapy treatment in India last year, which he called life-changing. He receives numerous Facebook requests from parents of autistic children who are curious to know more. He always begins his conversations by saying, “Go slowly and think hard about your decision.”
Source: Scientific American
Patient Suffers Severe Amnesia but Musical Memory Remains Intact
ScienceDaily (Aug. 21, 2012) — Together with his team, Prof. Christoph Ploner, director of the Department of Neurology at the Virchow campus, examined a professional cellist who suffered from encephalitis caused by a herpes virus. As a result of the inflammation, the patient developed serious disturbances in memory.
Both his memory for the past (retrograde amnesia), as well as the acquisition of new information (anterograde amnesia) were affected. Whereas the patient was unable to recount any events from his private or professional life, or remember any of his friends or relatives, he retained a completely intact musical memory. Furthermore, he was still able to sight-read and play the cello.
For the systematic examination of his musical memory, Dr. Carsten Finke, Nazli Esfahani and Prof. Christoph Ploner developed various tests that take the beginning of his amnesia into account. In comparison to amateur musicians and professional musicians from the Berlin Philharmonic, the patient showed a normal musical memory in all tests. He not only remembered music pieces from the past, but was also able to retain music he had never heard before.
"The findings show that musical memory is organized at least partially independent of the hippocampus, a brain structure that is central to memory formation," says Carsten Finke, the primary author of the study. "It is possible that the enormous significance of music throughout all times and in all cultures contributed to the development of an independent memory for music."
Carsten Finke and his colleagues hope that the intact musical memory in patients with amnesia can be used to stimulate other memory content. In this way, perhaps a particular melody can be connected to a person or an everyday task, for example taking medicine.
Source: Science Daily
MRI Findings Shed Light On Multiple Sclerosis
ScienceDaily (Aug. 21, 2012) — New magnetic resonance imaging (MRI) research shows that changes in brain blood flow associated with vein abnormalities are not specific for multiple sclerosis (MS) and do not contribute to its severity, despite what some researchers have speculated. Results of the research are published online in the journal Radiology.
"MRI allowed an accurate evaluation of cerebral blood flow that was crucial for our results," said Simone Marziali, M.D., from the Department of Diagnostic Imaging at the University of Rome Tor Vergata in Rome.
MS is a disease of the central nervous system in which the body’s immune system attacks the nerves. There are different types of MS, and symptoms and severity vary widely. Recent reports suggest a highly significant association between MS and chronic cerebrospinal venous insufficiency (CCSVI), a condition characterized by compromised blood flow in the veins that drain blood from the brain. This strong correlation has generated substantial attention from the scientific community and the media in recent years, raising the possibility that MS can be treated with endovascular procedures like stent placement. However, the role of brain blood flow alterations on MS patients is still unclear.
To investigate this further, Italian researchers compared brain blood flow in 39 MS patients and 26 healthy control participants. Twenty-five of the MS patients and 14 of the healthy controls were positive for CCSVI, based on Color-Doppler-Ultrasound (CDU) findings. The researchers used dynamic susceptibility contrast-enhanced (DSC) MRI to assess blood flow in the brains of the study groups. DSC MR imaging offers more accurate assessment of brain blood flow than that of CDU. MRI and CDU were used to assess two different anatomical structures.
While CCSVI-positive patients showed decreased cerebral blood flow and volume compared with their CCSVI-negative counterparts, there was no significant interaction between MS and CCSVI for any of the blood flow parameters. Furthermore, the researchers did not find any correlation between the cerebral blood flow and volume in the brain’s white matter and the severity of disability in MS patients.
The results suggest that CCSVI is not a pathological condition correlated with MS, according to Dr. Marziali, but probably just an epiphenomenon — an accessory process occurring in the course of a disease that is not necessarily related to the disease. This determination is important because, to date, studies of the prevalence of CCSVI in MS patients have provided inconclusive results.
"This study clearly demonstrates the important role of MRI in defining and understanding the causes of MS," Dr. Marziali said. "I believe that, in the future, it will be necessary to use powerful and advanced diagnostic tools to obtain a better understanding of this and other diseases still under study."
Source: Science Daily
The gears that help cells divide are coming into clearer focus. Researchers have used a new type of super-resolution microscopy to zoom in on centrosomes, which anchor the fibers that enable chromosomes to separate during cell division. Centrosomes have intrigued scientists since their discovery in the late 1800s, in part because cancer cells often amass extra copies of the structures. But they’re so tiny that they’re barely visible through traditional light microscopes, and researchers haven’t nailed down how they form and what role they play in cancer. So cell biologist David Glover of the University of Cambridge in the United Kingdom and his postdoc Jingyan Fu turned to three-dimensional structured illumination microscopy to provide sharper portraits of centrosomes and to pinpoint several proteins they harbor. Each centrosome consists of two cylindrical components called centrioles shrouded by a molecular cloud, which balloons when cells start the process of division. As the team reveals online today in Open Biology, many of the cloud proteins first gather on the centrioles, moving into the cloud once division begins. That’s the case with the protein Cnn (green), shown above close to the cylindrical centriole (top) and dispersed in the cloud (bottom, inset). With further research, scientists might be able to determine how different proteins interact to construct centrosomes. “We can put the molecular jigsaw together,” Glover says.