Sunday, September 23, 2012

In vivo genome editing using a high-efficiency TALEN system

Improvements in artificial transcription activator-like effector nucleases (TALENs) provide a powerful new approach for targeted zebrafish genome editing and functional genomic applications1–5. Using the Goldy TALEN modified scaffold and zebrafish delivery system, it was shown that this enhanced TALEN toolkit has a high efficiency in inducing locus-specific DNA breaks in somatic and germline tissues. 
Science
Nature (2013) Sept 23 

Saturday, September 22, 2012

ENCODE Project Writes Eulogy For Junk DNA

30 research papers, including six in Nature and additional papers published by Science, sound the death knell for the idea that our DNA is mostly littered with useless bases. A decadelong project, the Encyclopedia of DNA Elements (ENCODE), has found that 80% of the human genome serves some purpose, biochemically speaking.

Monday, September 17, 2012

Axion search by Liquid Xenon

Arisaka's group has studied a possibility of searching for axion and axion-like particles by liquid Xenon detectors such as XENON100 and XENON1T.
The paper has been submitted to Astroparticle Physcis Journal, and available at
http://arxiv.org/abs/1209.3810

Friday, September 14, 2012

Disorder of Neuronal Circuits in Autism Is Reversible, New Study Suggests

People with autism suffer from a pervasive developmental disorder of the brain that becomes evident in early childhood. Peter Scheiffele and Kaspar Vogt, Professors at the Biozentrum of the University of Basel, have identified a specific dysfunction in neuronal circuits that is caused by autism. In the journal Science, the scientists also report about their success in reversing these neuronal changes. These findings are an important step in drug development for the treatment for autism.Science
Daily Sept 22, 2012
St├ęphane J. Baudouin, et al.
Shared Synaptic Pathophysiology in Syndromic and Nonsyndromic Rodent Models of Autism. Science, 13 September 2012 DOI: 10.1126/science.1224159


Wednesday, September 12, 2012

Cross-sensory transfer of sensory-motor information: visuomotor learning affects performance on an audiomotor task, using sensory-substitution

Visual-to-auditory sensory-substitution devices allow users to perceive a visual image using sound. Using a motor-learning task, researchers in Israel found that new sensory-motor information was generalized across sensory modalities. They imposed a rotation when participants reached to visual targets, and found that not only seeing, but also hearing the location of targets via a sensory-substitution device resulted in biased movements. When the rotation was removed, aftereffects occurred whether the location of targets was seen or heard. Their findings demonstrate that sensory-motor learning was not sensory-modality-specific. They conclude that novel sensory-motor information can be transferred between sensory modalities.


Reversible switching between epigenetic states in honeybee behavioral subcastes

In honeybee societies, distinct caste phenotypes are created from the same genotype, suggesting a role for epigenetics in deriving these behaviorally different phenotypes. The authors found no differences in DNA methylation between irreversible worker and queen castes, but substantial differences between nurses and forager subcastes. Reverting foragers back to nurses reestablished methylation levels for a majority of genes and provides the first evidence in any organism of reversible epigenetic changes associated with behavior.

Brian R Herb & Andrew P Feinberg et al.
Nature Neuroscience 15, 1371–1373 (2012) doi:10.1038/nn.3218
Published online 16 September 2012


Thursday, September 6, 2012

Stem Cell Revolution: Regenerating the Eye

Research is breaking new ground that promises to change our ability to treat eye disease forever.

Although stem cells were discovered in the mid-1800s and the subject of experimentation in the early 1900s, it’s only been in recent decades that they’ve truly caught the imagination of medical researchers and the public. Today, our understanding of these cells is expanding dramatically, and research has proliferated as their potential has become clear. Nevertheless, stem cell research is still in its infancy. Because a host of basic questions remain unanswered, research around the world is moving in multiple directions, testing many different possible ways to derive stem cells and apply them in vitro for research and in vivo for treating or preventing disease.

A stem cell is defined as an undifferentiated cell that has the potential to become a number of specific cell types. However, depending on the derivation of the stem cell, its fundamental characteristics may be significantly different. There are four primary stem cell types: embryonic, taken from very early fertilized embryos; parthenogenetic, taken from unfertilized eggs with a simpler genetic sequence for researchers to manage; so-called adult stem cells, found in different organs and designed to differentiate into the cell types found in that organ only; and induced pluripotent stem cells, which are differentiated cells (for example, skin cells) that are coaxed into returning to an undifferentiated state, from which they may then evolve into any number of other cell types. Each type of stem cell has specific advantages and drawbacks that make it better suited—at least in theory—for specific applications.

As is often the case in medical research, the eye has become a popular target. That’s partly because results are typically easier to monitor in the eye than in other organs, and partly because much of the eye in immune-privileged, making it receptive to treatments that might trigger rejection in other parts of the body. Current targets include the retina, cornea, trabecular meshwork and simply stabilizing abnormal blood vessels.


Saturday, September 1, 2012

Clue to Cause of Alzheimer's Dementia Found in Brain Samples

Researchers at Washington University School of Medicine in St. Louis have found a key difference in the brains of people with Alzheimer's disease and those who are cognitively normal but still have brain plaques that characterize this type of dementia.
The new study, available online inAnnals of Neurology, still implicates amyloid beta in causing Alzheimer's dementia, but not necessarily in the form of plaques. Instead, smaller molecules of amyloid beta dissolved in the brain fluid appear more closely correlated with whether a person develops symptoms of dementia. Called amyloid beta "oligomers," they contain more than a single molecule of amyloid beta but not so many that they form a plaque.
Science Daily, Oct 22, 2012
Esparza TJ et al.
Amyloid-beta oligomerization in Alzheimer dementia versus high-pathology controls.