Tiny Brain Parts Teased From Stem Cells This isn the first time stem cells have been used to help develop hearts.
The protein impairs the formation of new brain cells and contributes to age-related memory losst least in mice, according to a new study.
Neuroscientist Saul Villeda of UCSF homed in on one actor he thought might be responsible for some of that effect:
Moreover, their brains had fewer new neurons than other mice. Thirty days later, however, when the protein had been cleared from their bodies,
and the number of newly formed brain cells was back to normal. To see whether reducing B2m levels could treat
suggesting that B2m is part of a pathway that affects the brain. hat this shows is that you can manipulate the blood, rather than the brain, to potentially treat memory problems,
and restore brain cell formation. The real test, Conboy says, will come in clinical trials that aim to block B2mr other related moleculeso treat
but a small amount of fluorescence in the brain which is a destination for much of the Vitamin c produced in the liver.
Another possible application is engineering brain cells of living animals or human cells grown in a petri dish to allow researchers to track
or whether a neuron is active at a certain time. If you could turn the DNA inside a cell into a little memory device on its own
receiving pacemaker implants in his chest that could intercept aberrant signals from his brain before they reached his muscles.
A new study from MIT Brigham and Women s Hospital and Johns hopkins university suggests that delivering chemotherapy directly into the brain cavity may offer a better way to treat tumors that have metastasized to the brain.
because it s not getting to the brain at a high enough dose for a long enough period of time says Cima who is also a member of MIT s Koch Institute for Integrative Cancer Research.
To overcome these delivery issues Cima s lab is working on small implantable devices to deliver drugs for ovarian cancer and bladder disease as well as brain cancer.
For the new brain study the researchers delivered chemotherapy drugs via implantable microcapsules made of a biocompatible material called liquid crystal polymer.
TMZ which is a first-line treatment for brain metastasis and gliomas and doxorubicin a common treatment for breast cancer
which often metastasizes to the brain. Zone of influenceworking with mice implanted with tumors similar to human brain metastases the researchers found that TMZ delivered directly to the brain prolonged survival by several days compared with TMZ administered by injection.
They also found higher rates of apoptosis or programmed cell death in tumor cells near the capsules.
However doxorubicin delivered to the brain did not perform as well as systemic injection of doxorubicin. As an explanation for that discrepancy the researchers found that TMZ travels farther from the capsule after release allowing it to reach more tissue.
After they have their brain metastases surgically taken out you could put in these microcapsules which would kill any remaining cancer cells right then and there.
because so many cancers particularly those of the breast and lung spread to the brain. The researchers are also working on using this approach to precisely deliver drugs to very small regions of the brain in hopes of developing better treatments for psychiatric and neurodegenerative disorders.
The research was funded by the National institutes of health and the Brain science Foundation n
#Microscopic walkers find their way across cell surfaces Nature has developed a wide variety of methods for guiding particular cells enzymes and molecules to specific structures inside the body:
White blood cells can find their way to the site of an infection while scar-forming cells migrate to the site of a wound.
and brain to model tumors in those regions the researchers say. This method also offers new ways to seek personalized treatments for cancer patients depending on the types of mutations found in their tumors the researchers say.
if they displayed any fluorescent protein in the brain indicating whether the RNA successfully entered the brain tissue was taken up by the cells
and expressed the desired protein. The researchers found that several lipidoids that had performed not well in cultured cells did deliver RNA efficiently in the zebrafish model.
or other large molecules to enter the brain through the bloodstream.##The research was funded by the National institutes of health the Packard Award in Science and Engineering Sanofi Pharmaceuticals Foxconn Technology Group and the Hertz Foundation e
But the brain behind those Hollywood interfaces, MIT alumnus John Underkoffler 8, SM 1, Phd 9 who served as scientific advisor for both films has been bringing a more practical version of that technology to conference rooms
#Neuroscientists reverse memories emotional associations Most memories have some kind of emotion associated with them: Recalling the week you just spent at the beach probably makes you feel happy
A new study from MIT neuroscientists reveals the brain circuit that controls how memories become linked with positive or negative emotions.
Furthermore the researchers found that they could reverse the emotional association of specific memories by manipulating brain cells with optogenetics a technique that uses light to control neuron activity.
The findings described in the Aug 27 issue of Nature demonstrated that a neuronal circuit connecting the hippocampus
and the amygdala plays a critical role in associating emotion with memory. This circuit could offer a target for new drugs to help treat conditions such as posttraumatic stress disorder the researchers say In the future one may be able to develop methods that help people to remember positive memories more strongly than negative ones says Susumu Tonegawa the Picower
and Neuroscience director of the RIKEN-MIT Center for Neural Circuit Genetics at MIT s Picower Institute for Learning and Memory and senior author of the paper.#
which are stored in different parts of the brain. A memory s context including information about the location where the event took place is stored in cells of the hippocampus
while emotions linked to that memory are found in the amygdala. Previous research has shown that many aspects of memory including emotional associations are malleable.
Psychotherapists have taken advantage of this to help patients suffering from depression and posttraumatic stress disorder but the neural circuitry underlying such malleability is known not.
In this study the researchers set out to explore that malleability with an experimental technique they recently devised that allows them to tag neurons that encode a specific memory or engram.
To achieve this they label hippocampal cells that are turned on during memory formation with a light-sensitive protein called channelrhodopsin.
First they used their engram-labeling protocol to tag neurons associated with either a rewarding experience (for male mice socializing with a female mouse) or an unpleasant experience (a mild electrical shock.
In this first set of experiments the researchers labeled memory cells in a part of the hippocampus called the dentate gyrus.
and had avoided the side of the chamber where their hippocampal cells were activated by the laser now began to spend more time in that side
when their hippocampal cells were activated showing that a pleasant association had replaced the fearful one. This reversal also took place in mice that went from reward to fear conditioning.
but labeled memory cells in the basolateral amygdala a region involved in processing emotions. This time they could not induce a switch by reactivating those cells the mice continued to behave as they had been conditioned
This suggests that emotional associations also called valences are encoded somewhere in the neural circuitry that connects the dentate gyrus to the amygdala the researchers say.
and fear-encoding cells in the amygdala but that connection can be weakened later on as new connections are formed between the hippocampus
and amygdala cells that encode positive associations. That plasticity of the connection between the hippocampus and the amygdala plays a crucial role in the switching of the valence of the memory Tonegawa says.
These results indicate that while dentate gyrus cells are neutral with respect to emotion individual amygdala cells are precommitted to encode fear
or reward memory. The researchers are now trying to discover molecular signatures of these two types of amygdala cells.
They are also investigating whether reactivating pleasant memories has any effect on depression in hopes of identifying new targets for drugs to treat depression and posttraumatic stress disorder.
David Anderson a professor of biology at the California Institute of technology says the study makes an important contribution to neuroscientists fundamental understanding of the brain
and also has potential implications for treating mental illness. This is a tour de force of modern molecular-biology-based methods for analyzing processes such as learning and memory at the neural-circuitry level.
The research was funded by the RIKEN Brain science Institute Howard hughes medical institute and the JPB Foundation i
#Sorting cells with sound waves Researchers from MIT, Pennsylvania State university, and Carnegie mellon University have devised a new way to separate cells by exposing them to sound waves as they flow through a tiny channel.
Because researchers cannot study the biochemistry of the living human brain the genes that predispose people to schizophrenia
and the critical underlying biological processes such as an impaired ability of neurons to communicate with each other.
As director Hyman led the NIMH to invest in both neuroscience and genetics and along with Scolnick and Lander supported the collection of DNA samples from patients with the hope that the samples could someday be analyzed to find disease genes.
and comprehensively measure the dynamic activity of genes in living cells including lab-grown neurons produced by new stem-cell technologies.
when and how these genes act in human brain cells and how in psychiatric patients those processes may go awry.
#Noninvasive brain control Optogenetics, a technology that allows scientists to control brain activity by shining light on neurons,
This technique requires a light source to be implanted in the brain, where it can reach the cells to be controlled.
MIT engineers have developed now the first light-sensitive molecule that enables neurons to be silenced noninvasively, using a light source outside the skull.
Led by Ed Boyden, an associate professor of biological engineering and brain and cognitive sciences at MIT, the researchers described the protein in the June 29 issue of Nature Neuroscience.
Optogenetics, a technique developed over the past 15 years, has become a common laboratory tool for shutting off or stimulating specific types of neurons in the brain,
allowing neuroscientists to learn much more about their functions. The neurons to be studied must be engineered genetically to produce light-sensitive proteins known as opsins,
which are channels or pumps that influence electrical activity by controlling the flow of ions in or out of cells.
Researchers then insert a light source, such as an optical fiber, into the brain to control the selected neurons.
Such implants can be difficult to insert, however, and can be incompatible with many kinds of experiments, such as studies of development, during
which the brain changes size, or of neurodegenerative disorders, during which the implant can interact with brain physiology.
In addition, it is difficult to perform long-term studies of chronic diseases with these implants. To find a better alternative, Boyden, graduate student Amy Chuong,
these molecules, found in the bacteria Haloarcula marismortui and Haloarcula vallismortis, did not induce a strong enough photocurrent an electric current in response to light to be useful in controlling neuron activity.
but had a much stronger photocurrent enough to shut down neural activity. his exemplifies how the genomic diversity of the natural world can yield powerful reagents that can be of use in biology and neuroscience,
who is a member of MIT Media Lab and the Mcgovern Institute for Brain Research.
the researchers were able to shut down neuronal activity in the mouse brain with a light source outside the animal head.
The suppression occurred as deep as 3 millimeters in the brain, and was just as effective as that of existing silencers that rely on other colors of light delivered via conventional invasive illumination.
A key advantage to this opsin is that it could enable optogenetic studies of animals with larger brains,
says Garret Stuber, an assistant professor of psychiatry and cell biology and physiology at the University of North carolina at Chapel hill. n animals with larger brains,
which could be controlled by shutting off misfiring neurons that cause seizures, Boyden says. ince these molecules come from species other than humans,
#Illuminating neuron activity in 3-D Researchers at MIT and the University of Vienna have created an imaging system that reveals neural activity throughout the brains of living animals.
This technique, the first that can generate 3-D movies of entire brains at the millisecond timescale,
The team used the new system to simultaneously image the activity of every neuron in the worm Caenorhabditis elegans,
as well as the entire brain of a zebrafish larva, offering a more complete picture of nervous system activity than has been previously possible. ooking at the activity of just one neuron in the brain doesn tell you how that information is being computed;
for that, you need to know what upstream neurons are doing. And to understand what the activity of a given neuron means,
you have to be able to see what downstream neurons are doing, says Ed Boyden, an associate professor of biological engineering and brain and cognitive sciences at MIT and one of the leaders of the research team. n short,
if you want to understand how information is being integrated from sensation all the way to action, you have to see the entire brain.
The new approach, described May 18 in Nature Methods, could also help neuroscientists learn more about the biological basis of brain disorders. e don really know
for any brain disorder, the exact set of cells involved, Boyden says. he ability to survey activity throughout a nervous system may help pinpoint the cells
or networks that are involved with a brain disorder, leading to new ideas for therapies. Boyden team developed the brain-mapping method with researchers in the lab of Alipasha Vaziri of the University of Vienna and the Research Institute of Molecular Pathology in Vienna.
The paper lead authors are Young-Gyu Yoon, a graduate student at MIT, and Robert Prevedel, a postdoc at the University of Vienna.
High-speed 3-D imaging Neurons encode information sensory data motor plans, emotional states, and thoughts using electrical impulses called action potentials,
which provoke calcium ions to stream into each cell as it fires. By engineering fluorescent proteins to glow when they bind calcium,
scientists can visualize this electrical firing of neurons. However, until now there has been no way to image this neural activity over a large volume, in three dimensions,
and at high speed. Scanning the brain with a laser beam can produce 3-D images of neural activity,
but it takes a long time to capture an image because each point must be scanned individually.
The MIT team wanted to achieve similar 3-D imaging but accelerate the process so they could see neuronal firing,
to imaging neural activity. With this kind of microscope, the light emitted by the sample being imaged is sent through an array of lenses that refracts the light in different directions.
who is a member of MIT Media Lab and Mcgovern Institute for Brain Research. Prevedel built the microscope,
Neurons in action The researchers used this technique to image neural activity in the worm C. elegans, the only organism for
This 1-millimeter worm has 302 neurons, each of which the researchers imaged as the worm performed natural behaviors, such as crawling.
The current resolution is high enough to see activity of individual neurons but the researchers are now working on improving it so the microscope could also be used to image parts of neurons,
such as the long dendrites that branch out from neuronsmain bodies. They also hope to speed up the computing process,
which currently takes a few minutes to analyze one second of imaging data. The researchers also plan to combine this technique with optogenetics,
By stimulating a neuron with light and observing the results elsewhere in the brain, scientists could determine which neurons are participating in particular tasks.
Other co-authors at MIT include Nikita Pak, a Phd student in mechanical engineering, and Gordon Wetzstein, a research scientist at the Media Lab. The work at MIT was funded by the Allen Institute for Brain science;
the National institutes of health; the MIT Synthetic Intelligence Project; the IET Harvey Prize; the National Science Foundation (NSF;
the New york Stem Cell Foundation-Robertson Award; Google; the NSF Center for Brains, Minds, and Machines at MIT;
and Jeremy and Joyce Wertheimer n
#Glasses-free 3-D projector Over the past three years, researchers in the Camera Culture group at the MIT Media Lab have refined steadily a design for a glasses-free, multiperspective, 3-D video screen,
the Pediatric Brain Tumour Fund, the Deutsche Forschungsgemeinschaft, Alnylam, and the Center for RNA Therapeutics and Biology e
#Delving deep into the brain Launched in 2013, the national BRAIN INITIATIVE aims to revolutionize our understanding of cognition by mapping the activity of every neuron in the human brain,
revealing how brain circuits interact to create memories, learn new skills, and interpret the world around us.
Before that can happen, neuroscientists need new tools that will let them probe the brain more deeply
and in greater detail, says Alan Jasanoff, an MIT associate professor of biological engineering. here a general recognition that in order to understand the brain processes in comprehensive detail,
we need ways to monitor neural function deep in the brain with spatial, temporal, and functional precision, he says.
Jasanoff and colleagues have taken now a step toward that goal: They have established a technique that allows them to track neural communication in the brain over time,
using magnetic resonance imaging (MRI) along with a specialized molecular sensor. This is the first time anyone has been able to map neural signals with high precision over large brain regions in living animals,
offering a new window on brain function, says Jasanoff, who is also an associate member of MIT Mcgovern Institute for Brain Research.
His team used this molecular imaging approach, described in the May 1 online edition of Science,
to study the neurotransmitter dopamine in a region called the ventral striatum, which is involved in motivation,
reward, and reinforcement of behavior. In future studies, Jasanoff plans to combine dopamine imaging with functional MRI techniques that measure overall brain activity to gain a better understanding of how dopamine levels influence neural circuitry. e want to be able to relate dopamine
signaling to other neural processes that are going on, Jasanoff says. e can look at different types of stimuli
and try to understand what dopamine is doing in different brain regions and relate it to other measures of brain function.
Tracking dopamine Dopamine is one of many neurotransmitters that help neurons to communicate with each other over short distances.
Much of the brain dopamine is produced by a structure called the ventral tegmental area (VTA.
This dopamine travels through the mesolimbic pathway to the ventral striatum, where it combines with sensory information from other parts of the brain to reinforce behavior
and help the brain learn new tasks and motor functions. This circuit also plays a major role in addiction.
To track dopamine role in neural communication, the researchers used an MRI sensor they had designed previously,
consisting of an iron-containing protein that acts as a weak magnet. When the sensor binds to dopamine, its magnetic interactions with the surrounding tissue weaken,
which dims the tissue MRI signal. This allows the researchers to see where in the brain dopamine is being released.
The researchers also developed an algorithm that lets them calculate the precise amount of dopamine present in each fraction of a cubic millimeter of the ventral striatum.
After delivering the MRI sensor to the ventral striatum of rats, Jasanoff team electrically stimulated the mesolimbic pathway
and was able to detect exactly where in the ventral striatum dopamine was released. An area known as the nucleus accumbens core, known to be one of the main targets of dopamine from the VTA,
showed the highest levels. The researchers also saw that some dopamine is released in neighboring regions such as the ventral pallidum,
which regulates motivation and emotions, and parts of the thalamus, which relays sensory and motor signals in the brain.
Each dopamine stimulation lasted for 16 seconds and the researchers took an MRI image every eight seconds,
allowing them to track how dopamine levels changed as the neurotransmitter was released from cells and then disappeared. e could divide up the map into different regions of interest
and determine dynamics separately for each of those regions, Jasanoff says. He and his colleagues plan to build on this work by expanding their studies to other parts of the brain,
including the areas most affected by Parkinson disease, which is caused by the death of dopamine-generating cells.
Jasanoff lab is also working on sensors to track other neurotransmitters, allowing them to study interactions between neurotransmitters during different tasks.
The paper lead author is postdoc Taekwan Lee. Technical assistant Lili Cai and postdocs Victor Lelyveld and Aviad Hai also contributed to the research
which was funded by the National institutes of health and the Defense Advanced Research Projects Agency h
#MIT team wins Clean energy Prize for solving solar s shade problem An MIT team whose integrated chip restores lost power to partially shaded solar panels achieving double the energy capture improvement of similar technologies won big on Monday night at the seventh annual MIT Clean energy Prize (CEP) competition.
Equipped with a promising business plan and a snappy catchphrase hade happensunified Solar took home both CEP grand prizes:
the DOE Energy efficiency and Renewable energy Clean energy Prize, worth $100, 000, and the NSTAR MIT Clean energy Prize, worth $125, 000.
Solar panels on residential rooftops that are shaded partially by clouds or trees sacrifice as much as 30 percent of their energy potential over a year.
and brains work and translates that knowledge into technology that reflects those principles leading to a world where technology
#Seeking a parts list for the retina New technique classifies retinal neurons into 15 categories,
many types of neurons in our retinas interact to analyze different aspects of what we see
Neuroscientists believe there are 20 to 30 types of these specialized neurons, known as retinal ganglion cells,
A new study from MIT neuroscientists has made some headway on this daunting task. Using a computer algorithm that traces the shapes of neurons and groups them based on structural similarity,
the researchers sorted more than 350 mouse retinal neurons into 15 types, including six that were unidentified previously.
This technique, described in the March 24 online edition of Nature Communications, could also be deployed to help identify the huge array of neurons found in the brain cortex,
says Uygar Sumbul, an MIT postdoc and one of the lead authors of the paper. his delineates a program that we should be doing for the rest of the retina,
and elsewhere in the brain, to robustly and precisely know the cell types, he says.
Sebastian Seung, a former MIT professor of brain and cognitive sciences and physics who is now at Princeton university,
which relay visual input through several layers of neurons in the retina. The final layer is composed of ganglion cells,
which feed information to the brain visual processing regions via the optic nerve. Neuroscientists have identified at least nine types of ganglion cells with distinct functions, structures,
and genetic makeup. For example the so-called cellsrespond only to upward motion and express an adhesion molecule called JAM-B that helps them connect with the other cells they need to communicate with.
Other known ganglion types respond only when light is turned on or off, and still others monitor the overall level of light
and send the information to parts of the brain that control circadian rhythms. These genetically and functionally defined cell types offered a valuable starting point for the new study,
which aimed to create a system that would accurately classify known neurons and also assign unknown neurons to the correct groups.
To begin the researchers used a light microscope to image individual neurons in the brains of mice that had been engineered genetically so that one class of ganglions,
such as the J cell, is tagged with a fluorescent protein. They also obtained images of unidentified neurons using mice genetically engineered
so that only a few of their ganglion neurons fluoresce. In total, the researchers imaged 363 cells 111 that were known genetically
and 252 that were selected randomly. Using a computer algorithm, they traced along the many branches, known as dendrites,
that extend from each cell to connect with other cells. These dendrites form clusters called arbors
which were the key to the researchersclassification system. After each neuron arbor was diagrammed, the researchers used a computer program to align
and condense each one so that the arbors were represented by smaller, but still distinctive, shapes. By comparing these shapes,
the computer program correctly classified all of the known neurons. Among the randomly selected neurons, some ended up being grouped with the known types,
while others formed six new clusters yet to be identified. This approach is an important contribution to efforts to create a arts listfor the retina,
which is necessary to help researchers learn more about how the eye and brain interpret visual information,
says Constance Cepko, a professor of genetics at Harvard Medical school. Previous efforts have focused on analyzing only a small number of cell types at a time,
While the bodies of the ganglion cells all stay in the same layer each neuron dendrites travel to other layers to interact with other cells.
This stratification is very specific to each cell type, ensuring that the neurons are communicating with the correct partners as they relay visual information.
The researchers believe there may be still more types of neurons that did not appear in their data set
and remain to be identified. In future work, they hope to examine larger sets of neurons in hopes of finding some of these other neuron types.
They also hope to use their technique to study parts of the brain that have many layers of neurons especially the neocortex
where most cognitive functions take place. The research was funded by the Harvard Neurodiscovery Center, the Howard hughes medical institute, the Gatsby Charitable Foundation,
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