Engineered virus to make triple negative breast cancer cells susceptible to radioactive iodine

While it is still too early to make any claims of a cure - having not even proceeded to human clinical trials yet - the researchers behind the method are hopeful because it basically combines known cures for two other diseases: the virus (vaccinia virus GLV-1h153) is apparently very similar to the one used to help eradicate smallpox, while the protein the breast cancer cells are made to express (hNIS) is the same one that is responsible for making many thyroid cancers treatable using a small dose of radioactive iodine. http://bit.ly/1o13oXi

Image: A breast cancer cell, photographed by a scanning electron microscope. NCI/Wikimedia Commons

An Alzheimer's risk gene may begin to affect the brain even in childhood

Alzheimer's is generally thought of as an illness of old age. But new research published in Molecular Psychiatry shows that a gene variant known to increase the risk of developing Alzheimer's disease can begin affecting brains even in childhood. Researchers at the Centre for Addiction and Mental Health in Toronto, Canada were studying a gene known as SORL1 to try and figure out the biological pathways through which it increased the risk of late-onset Alzheimer's disease. To understand the effects of SORL1 across the lifespan, the researchers used a combination of diffusion tensor imaging and detailed study of post-mortem brain tissue in individuals aged 0 to 108. Even in young children carrying the variant of SORL1 linked to increased Alzheimer's risk, the brain's white matter and executive functioning were altered, as were the translation and transcription of SORL1. Although carrying this risk gene is just one factor in the ultimate development of Alzheimer's disease, the researchers say that knowing individuals at highest risk will help target more effective prevention efforts.

Read more: http://bit.ly/1axOwFM
Journal article: The SORL1 gene and convergent neural risk for Alzheimer’s disease across the human lifespan. Molecular Psychiatry, 2013. doi:10.1038/mp.2013.142

Mitochondria may hold the key to a reversible form of aging

A breakdown in cellular communication in the cell may be partly responsible for the aging process, report researchers at Harvard University in a new study. In work published in Cell, the researchers also indicate that restoring this communication can reverse aging. Their work hinges on the mitochondria, which are the power plants of the cell and produce its energy. Mitochondria have their own small genomes that are independent from nuclear DNA. The scientists found that, while mitochondrial proteins encoded by nuclear DNA remained normal, proteins from mitochondrial genes deteriorated during aging. The cause of this, the scientists found, was a breakdown of the cascade of communication between mitochondrial proteins. But when the scientists gave mice a compound that could restore functioning of a chemical crucial to this communication cascade, they found that they could reverse many of the signs of aging in muscle cells. Experiments are ongoing to determine what happens to the mouse on the organismal level, and the effects of chronic administration.

Read more: http://bit.ly/1gJdNVV
Journal article: Declining NAD+ Induces a Pseudohypoxic State Disrupting Nuclear-Mitochondrial Communication during Aging. Cell, 2013. doi: 10.1016/j.cell.2013.11.037

Brain reorganization occurs earlier in girls, explains why they mature faster

As we grow and mature, our brains also undergo significant reorganization and pruning. A detailed study of how the brain's connectivity changes over time recently published in the journal Cerebral Cortex reveals that this reorganization tends to happen earlier in girls, which may help explain why they mature faster. Neuroscientists at Newcastle University in the UK used diffusion tensor imaging to study the brain's wiring in 121 healthy people between the ages of 4 and 40. The researchers found that connections in the brain tend to get more streamlined over time, which can allow for faster and more efficient information processing. Still, plenty of long-range connections are preserved, especially those that play a role in integrating information. The scientists found that this process happens earlier in females and may explain why girls tend to reach maturity faster: their brains become more efficient at information processing at an earlier age than boys. The research may also help shed light on alterations in brain connectivity that have been linked to disorders like schizophrenia and autism.

Read more: http://bit.ly/1eqhLCI
Journal article: Preferential Detachment During Human Brain Development: Age- and Sex-Specific Structural Connectivity in Diffusion Tensor Imaging (DTI) Data. Cerebral Cortex 2013; doi: 10.1093/cercor/bht333

Molecular Robots Can Help Researchers Build More Targeted Therapeutics

All cells possess receptors on their cell surface. Drugs bind to their receptors in order to trigger the cells to perform. Since disease-causing cells' receptors may not have unique receptor compare to the healthy cells it would create a complexity which means the drugs target disease-causing cells as well as healthy cells. To overcome this challenge scientists have designed molecular robots that can identify multiple receptors on cell surfaces, thereby effectively labeling more specific subpopulations of cells. The molecular robots, called molecular automata, are composed of a mixture of antibodies and short strands of DNA (oligonucleotides). The researchers conducted their experiments using white blood cells. All white blood cells have CD45 receptors, but only subsets have other receptors such as CD20, CD3, and CD8. In one experiment, HSS researchers created three different molecular robots. Each one had an antibody component of either CD45, CD3 or CD8 and a DNA component. The DNA components of the robots were created to have a high affinity to the DNA components of another robot. DNA can be thought of as a double stranded helix that contains two strands of coded letters, and certain strands have a higher affinity to particular strands than others. The researchers mixed human blood from healthy donors with their molecular robots. When a molecular robot carrying a CD45 antibody latched on to a CD45 receptor of a cell and a molecular robot carrying a CD3 antibody latched on to a different welcoming receptor of the same cell, the close proximity of the DNA strands from the two robots triggered a cascade reaction, where certain strands were ripped apart and more complementary strands joined together. The result was a unique, single strand of DNA that was displayed only on a cell that had these two receptors. The addition of a molecular robot carrying a CD8 antibody docking on a cell that expressed CD45, CD3 and CD8 caused this strand to grow. The researchers also showed that the strand could be programmed to fluoresce when exposed to a solution. The robots can essentially label a subpopulation of cells allowing for more targeted therapy. The researchers say the use of increasing numbers of molecular robots will allow researchers to zero in on more and more specific subsets of cell populations.

Read more: http://bit.ly/13znLSy 
                   http://bit.ly/16k4o0e

Switch from conscious to unconscious learning systems

Most students know a thing or two about learning while stressed. New research from Ruhr-University Bochum in Germany found that a certain type of cellular receptor is key to learning under pressure, according to a new study published in Biological Psychiatry. Mineralcorticoid receptors bind to molecules like the stress hormone cortisol. These receptors, the researchers found, signaled a shift from conscious to unconscious learning in people. When these receptors were blocked, individuals were less able to deliberately learn the rules to a weather prediction game. This blockage didn't affect those who were told to go with their gut and figure out the rules. Shifting learning strategies is a fundamental mechanism in adapting to stressful situations, the researchers say.

Read more: http://bit.ly/1bXvuiIJournal article: Mineralocorticoid Receptor Blockade Prevents Stress-Induced Modulation of Multiple Memory Systems in the Human Brain. Biological Psychiatry, 2013. doi:10.1016/j.biopsych.2013.06.001

Speedier scans reveal new distinctions in resting and active brain

Better, faster brain scans are helping scientists get a more accurate picture of how neurons gather together in groups called networks. In a new study published in Neuron, scientists at Washington University in St. Louis used a new technique called magnetoencephalography (MEG, pictured) to watch how neurons communicate with each other. The researchers recorded the brain activity of two groups of people: one who were resting and watching a move, and the other that was instructed to notice specific changes in movie scenery and plot. Changes in movie scenery was associated with specific changes in neural networks in the visual cortex. Whereas fMRI can only record brain activity that cycles once every 10 seconds, MEG can record activity down to 50 cycles each second. This technique will greatly improve our understanding of the brain, researchers say.

Read more: http://bit.ly/12KbWum
Journal article: Natural Scenes Viewing Alters the Dynamics of Functional Connectivity in the Human Brain. Neuron, 2013. doi: 10.1016/j.neuron.2013.06.022
Image credit: Oxfordjournals