From Jason to Freddy, here's how several horror icons have been spending their time since their famous roles.
By Alex Zalben
WASHINGTON (AP) — More than 47 million Americans who receive food stamps will see their benefits go down starting Friday, just as Congress has begun negotiations on further cuts to the program.
Beginning in November, a temporary benefit from the 2009 economic stimulus that boosts food stamp dollars will no longer be available. According to the Agriculture Department, that means a family of four receiving food stamps will start receiving $36 less a month.
The benefits, which go to 1 in 7 Americans, fluctuate based on factors that include food prices, inflation and income. The rolls have swelled as the economy has struggled in recent years, with the stimulus providing higher benefits and many people signing up for the first time.
As a result, the program has more than doubled in cost since 2008, now costing almost $80 billion a year. That large increase in spending has turned the program, now called the Supplemental Nutrition Assistance Program, or SNAP, into a target for House Republicans looking to reduce spending.
Negotiations on a wide-ranging farm bill, including cuts to the SNAP program, began Wednesday. Five-year farm bills passed by both the House and the Senate would cut food stamps, reductions that would come on top of the cut that will go into effect Friday. But the two chambers are far apart on the amounts.
Legislation passed by the GOP-controlled House would cut food stamps by an additional $4 billion annually and tighten eligibility requirements. The House bill would also end government waivers that have allowed able-bodied adults without dependents to receive food stamps indefinitely and allow states to put broad new work requirements in place.
The Senate farm bill would cut a tenth of the House amount, with Democrats and President Barack Obama opposing major cuts.
Farm-state lawmakers have been pushing the farm bill for more than two years, and Wednesday's conference negotiations represented the opening round in final talks. If the bill is not passed by the end of the year and current farm law is not extended, certain dairy supports would expire that could raise the price of milk. Farmers would start to feel more effects next spring.
"It took us years to get here but we are here," House Agriculture Committee Chairman Frank Lucas, R-Okla., said. "Let's not take years to get it done."
The biggest obstacle to a final bill is how far apart the two parties are on food stamps. Lucas said at the conference meeting that he was hoping to find common ground on the issue, but House GOP leaders such as Rep. Eric Cantor, R-Va., have insisted on higher cuts, saying the program should be targeted to the neediest people.
House Minority Leader Nancy Pelosi, D-Calif., sent out a statement as the meeting opened that said food stamp recipients "deserve swift action from Congress to pass a bill that provides the much-needed nutritional support for our children, our seniors, our veterans and our communities."
As Congress debates the cuts to the program, charities say they are preparing for the farm bill reductions as well as the scheduled cuts taking place Friday.
"Charities cannot fill the gap for the cuts being proposed to SNAP," said Maura Daly of Feeding America, a network of the nation's food banks. "We are very concerned about the impact on the charitable system."
Daly says food banks may have to as much as double their current levels of distribution if the House cuts were enacted. The Congressional Budget Office says as many as 3.8 million people could lose their benefits in 2014 if the House bill became law.
___
Follow Mary Clare Jalonick on Twitter at http://twitter.com/mcjalonick
Associated PressSource: http://hosted2.ap.org/APDEFAULT/89ae8247abe8493fae24405546e9a1aa/Article_2013-10-31-Farm%20Bill-Food%20Stamps/id-14cd667a5a8442fc8300240b75998935NEW YORK (AP) — It's not coincidental that the stars of "Scandal" live tweet during episodes. They're encouraged to do so.
When several of the show's actors recently visited New York to promote the premiere of season three, ABC made sure to book Kerry Washington on a return flight to Los Angeles that offered Wi-Fi. Other cast members had their trips extended so they could be available on the social networking site.
Joshua Malina, who plays U.S. attorney David Rosen, relishes having a presence on Twitter. He describes his tweets as "self-promotion and dumb jokes."
A few examples:
—"Okay, how do we make the old chargers obsolete?" — first thing spoken at every Apple meeting about a new product."
—"Please watch Kerry Washington tonight on Kimmel as she continues her courageous battle against underexposure!"
—"If Lamar Odom and Khloe Kardashian can't make it, then ... nothing I can think of."
Malina may love Twitter but he wasn't an early fan.
"My sister was an early adopter. She lives in a remote area and what I could tell used Twitter to let my parents know that she was still alive. ... I thought, 'This thing is not gonna catch on.'"
Now he admits to sometimes crafting tweets and saving them for later.
"Occasionally I'll be driving around trying to formulate," he said. "The beauty of it is the enforced brevity forces you to craft your tweets, if you're attempting to be funny to really sort of pare it down so it's just right. I will work something over and over. Other times I'll read what's going on and instantly react."
Malina has no problem sparring with people who tweet him.
"Certainly these strangers who interact with me aren't holding back. People will tweet, 'You're ugly,'" he laughed. "I also have very, very thick skin ... so I don't mind reading the bad stuff."
He even prefers the negative over the positive.
"The good stuff is in a way less entertaining to read. I mean it's nice but you know ... people who want to really go after you I enjoy interacting with. I don't think I've ever actually been offended by anything anyone has written and I sort of hope people take it in the same spirit."
Malina doesn't hold back with celebs.
"Any celebrity that goes on Twitter and spouts off as if we should care what they say is opening himself or herself up to ridicule by anyone else."
"Scandal" airs Thursdays on ABC at 10 p.m. Eastern.
___
Alicia Rancilio covers entertainment for The Associated Press. Follow her online at http://www.twitter.com/aliciar
___
Online:
http://www.abc.go.com/shows/scandal/
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PUBLIC RELEASE DATE: 31-Oct-2013
ShareContact: NIAID Office of Communications
niaidnews@niaid.nih.gov
301-402-1663
NIH/National Institute of Allergy and Infectious Diseases
Using protein engineering and two different cutting-edge structural biology imaging techniques, researchers have developed a detailed picture of the protein largely responsible for enabling HIV to enter human immune cells and cause infection. An in-depth understanding of the atomic structure of the HIV envelope trimeror Env, the three-component protein found on HIV's surfaceis critical to better understanding how HIV gains entry into cells and for creating potential HIV vaccines.
Atomic-resolution imaging of the Env protein has previously been elusive because of the protein's complex, delicate structure. To capture the image, a team of scientists at The Scripps Research Institute and Weill Medical College of Cornell University engineered a more stable version of the protein. Then, in separate studies, using first cryo-electron microscopy and then X-ray crystallography, the researchers were able to reveal the structure of the Env trimer, how it assembles and how it interacts with broadly neutralizing antibodies that target HIV.
Their research, described in two papers published online today in Science Express, received major support from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.
###
ARTICLES:
D. Lyumkis et al. Cryo-EM Structure of a Fully Glycosylated Soluble Cleaved HIV-1 Env Trimer. Science Express DOI: 10.1126/science.1245627 (2013).
J.P. Julien et al. Crystal Structure of a Soluble Dleaved HIV-1 Envelope Trimer. Science Express DOI: 10.1126/science.1245625 (2013).
NIAID Director Anthony S. Fauci, M.D, is available to comment on both papers.
To schedule interviews, please contact the NIAID News Office, (301) 402-1663, niaidnews@niaid.nih.gov.
NIAID conducts and supports researchat NIH, throughout the United States, and worldwideto study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov/.
NIH...Turning Discovery Into Health
Share
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
PUBLIC RELEASE DATE: 31-Oct-2013
ShareContact: NIAID Office of Communications
niaidnews@niaid.nih.gov
301-402-1663
NIH/National Institute of Allergy and Infectious Diseases
Using protein engineering and two different cutting-edge structural biology imaging techniques, researchers have developed a detailed picture of the protein largely responsible for enabling HIV to enter human immune cells and cause infection. An in-depth understanding of the atomic structure of the HIV envelope trimeror Env, the three-component protein found on HIV's surfaceis critical to better understanding how HIV gains entry into cells and for creating potential HIV vaccines.
Atomic-resolution imaging of the Env protein has previously been elusive because of the protein's complex, delicate structure. To capture the image, a team of scientists at The Scripps Research Institute and Weill Medical College of Cornell University engineered a more stable version of the protein. Then, in separate studies, using first cryo-electron microscopy and then X-ray crystallography, the researchers were able to reveal the structure of the Env trimer, how it assembles and how it interacts with broadly neutralizing antibodies that target HIV.
Their research, described in two papers published online today in Science Express, received major support from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.
###
ARTICLES:
D. Lyumkis et al. Cryo-EM Structure of a Fully Glycosylated Soluble Cleaved HIV-1 Env Trimer. Science Express DOI: 10.1126/science.1245627 (2013).
J.P. Julien et al. Crystal Structure of a Soluble Dleaved HIV-1 Envelope Trimer. Science Express DOI: 10.1126/science.1245625 (2013).
NIAID Director Anthony S. Fauci, M.D, is available to comment on both papers.
To schedule interviews, please contact the NIAID News Office, (301) 402-1663, niaidnews@niaid.nih.gov.
NIAID conducts and supports researchat NIH, throughout the United States, and worldwideto study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov/.
NIH...Turning Discovery Into Health
Share
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
PUBLIC RELEASE DATE: 31-Oct-2013
ShareContact: Anne A. Oplinger
aoplinger@niaid.nih.gov
301-402-1663
NIH/National Institute of Allergy and Infectious Diseases
An experimental vaccine to protect against respiratory syncytial virus (RSV), a leading cause of illness and hospitalization among very young children, elicited high levels of RSV-specific antibodies when tested in animals, according to a report in the journal Science.
Early-stage human clinical trials of the candidate vaccine are planned. Scientists from the Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, built on their previous findings about the structure of a critical viral protein to design the vaccine. The team was led by Peter D. Kwong, Ph.D., and Barney S. Graham, M.D., Ph.D.
In the United States, RSV infection is the most common cause of bronchiolitis (inflammation of small airways in the lungs) and pneumonia in children less than one year old and the most common cause for hospitalization in children under five. Worldwide, it is estimated that RSV is responsible for nearly 7 percent of deaths in babies aged 1 month to 1 year; only malaria kills more children in this age group. Others at risk for severe disease following RSV infection include adults over age 65 and those with compromised immune systems.
Many common diseases of childhood are now vaccine-preventable, but a vaccine against RSV infection has eluded us for decades, said NIAID Director Anthony S. Fauci, M.D. This work marks a major step forward. Not only does the experimental vaccine developed by our scientists elicit strong RSV-neutralizing activity in animals, but, more broadly, this technique of using structural information to inform vaccine design is being applied to other viral diseases, including HIV/AIDS.
Earlier this year, the VRC team obtained atomic-level details of an RSV proteincalled the fusion (F) glycoproteinbound to a broadly neutralizing human RSV antibody. The protein-antibody complex gave scientists their first look at the F glycoprotein as it appears before it fuses with a human cell. In this pre-fusion shape, F glycoprotein contains a region vulnerable to attack by broadly neutralizing antibodies (antibodies able to block infection from the common strains of RSV).
Once RSV fuses with a cell, this vulnerable area, named antigenic site zero by the researchers, is no longer present on the rearranged F protein. In natural RSV infection, the immune system produces antibodies against both the pre-fusion and post-fusion forms of F glycoprotein, but the antibodies to antigenic site zero, which is only present on the pre-fusion form, have much stronger neutralizing activity. Therefore, a vaccine against RSV would have greater chance of success by eliciting antibodies directed at F glycoprotein in its pre-fusion configuration.
In their current publication, Drs. Kwong and Graham describe how they used this structural information to design and engineer F glycoprotein variants that retained antigenic site zero even when no antibody was bound to it. The goal was to create stable variants that could serve as the foundation for a vaccine capable of eliciting a potent antibody response. The researchers designed more than 100 variants; of these, 3 were shown by X-ray crystallography to retain the desired structure. The engineered variants were then used as vaccines in a series of experiments in mice and rhesus macaques.
In both mice and macaques, the researchers found that the more stable the protein, the higher the levels of neutralizing antibodies elicited by vaccination. The levels of antibody made in response to one of the engineered F glycoproteins were more than 10 times higher than those produced following vaccination with post-fusion F glycoprotein and well above levels needed to protect against RSV infection.
Here is a case in which information gained from structural biology has provided the insight needed to solve an immunological puzzle and apply the findings to address a real-world public health problem, said Dr. Graham. He and the VRC scientists are continuing to refine the engineered F glycoproteins and hope to launch early-stage human clinical trials of a candidate RSV vaccine as soon as clinical grade material can be manufactured, a process that takes about 18 to 24 months to complete.
Previously, structure-based vaccine design held promise at a conceptual level, said Dr. Kwong. This advance delivers on that promise and sets the stage for similar applications of structure-guided design to effective vaccines against other pathogens.
Dr. Fauci added, This latest advance underscores the advantages of the VRCs organizational design, where experts in RSV virology, vaccinology and clinical studies, such as Dr. Graham, are in daily contact with Dr. Kwong and others who are experts in structural biology. Such close collaboration across disciplines allows for rapid testing of new approaches to a given problem.
###
NIAID conducts and supports researchat NIH, throughout the United States, and worldwideto study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.
NIH...Turning Discovery Into Health
References:
JS McLellan et al. Structure-based design of a fusion glycoprotein vaccine for respiratory syncytial virus. Science DOI: 10.1126/science.1243283 (2013).
JS McLellan et al. Structure of RSV fusion glycoprotein trimer bound to a prefusion-specific neutralizing antibody. Science DOI: 10.1126/science.1234914 (2013).
PUBLIC RELEASE DATE: 31-Oct-2013
ShareContact: Anne A. Oplinger
aoplinger@niaid.nih.gov
301-402-1663
NIH/National Institute of Allergy and Infectious Diseases
An experimental vaccine to protect against respiratory syncytial virus (RSV), a leading cause of illness and hospitalization among very young children, elicited high levels of RSV-specific antibodies when tested in animals, according to a report in the journal Science.
Early-stage human clinical trials of the candidate vaccine are planned. Scientists from the Vaccine Research Center (VRC), National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, built on their previous findings about the structure of a critical viral protein to design the vaccine. The team was led by Peter D. Kwong, Ph.D., and Barney S. Graham, M.D., Ph.D.
In the United States, RSV infection is the most common cause of bronchiolitis (inflammation of small airways in the lungs) and pneumonia in children less than one year old and the most common cause for hospitalization in children under five. Worldwide, it is estimated that RSV is responsible for nearly 7 percent of deaths in babies aged 1 month to 1 year; only malaria kills more children in this age group. Others at risk for severe disease following RSV infection include adults over age 65 and those with compromised immune systems.
Many common diseases of childhood are now vaccine-preventable, but a vaccine against RSV infection has eluded us for decades, said NIAID Director Anthony S. Fauci, M.D. This work marks a major step forward. Not only does the experimental vaccine developed by our scientists elicit strong RSV-neutralizing activity in animals, but, more broadly, this technique of using structural information to inform vaccine design is being applied to other viral diseases, including HIV/AIDS.
Earlier this year, the VRC team obtained atomic-level details of an RSV proteincalled the fusion (F) glycoproteinbound to a broadly neutralizing human RSV antibody. The protein-antibody complex gave scientists their first look at the F glycoprotein as it appears before it fuses with a human cell. In this pre-fusion shape, F glycoprotein contains a region vulnerable to attack by broadly neutralizing antibodies (antibodies able to block infection from the common strains of RSV).
Once RSV fuses with a cell, this vulnerable area, named antigenic site zero by the researchers, is no longer present on the rearranged F protein. In natural RSV infection, the immune system produces antibodies against both the pre-fusion and post-fusion forms of F glycoprotein, but the antibodies to antigenic site zero, which is only present on the pre-fusion form, have much stronger neutralizing activity. Therefore, a vaccine against RSV would have greater chance of success by eliciting antibodies directed at F glycoprotein in its pre-fusion configuration.
In their current publication, Drs. Kwong and Graham describe how they used this structural information to design and engineer F glycoprotein variants that retained antigenic site zero even when no antibody was bound to it. The goal was to create stable variants that could serve as the foundation for a vaccine capable of eliciting a potent antibody response. The researchers designed more than 100 variants; of these, 3 were shown by X-ray crystallography to retain the desired structure. The engineered variants were then used as vaccines in a series of experiments in mice and rhesus macaques.
In both mice and macaques, the researchers found that the more stable the protein, the higher the levels of neutralizing antibodies elicited by vaccination. The levels of antibody made in response to one of the engineered F glycoproteins were more than 10 times higher than those produced following vaccination with post-fusion F glycoprotein and well above levels needed to protect against RSV infection.
Here is a case in which information gained from structural biology has provided the insight needed to solve an immunological puzzle and apply the findings to address a real-world public health problem, said Dr. Graham. He and the VRC scientists are continuing to refine the engineered F glycoproteins and hope to launch early-stage human clinical trials of a candidate RSV vaccine as soon as clinical grade material can be manufactured, a process that takes about 18 to 24 months to complete.
Previously, structure-based vaccine design held promise at a conceptual level, said Dr. Kwong. This advance delivers on that promise and sets the stage for similar applications of structure-guided design to effective vaccines against other pathogens.
Dr. Fauci added, This latest advance underscores the advantages of the VRCs organizational design, where experts in RSV virology, vaccinology and clinical studies, such as Dr. Graham, are in daily contact with Dr. Kwong and others who are experts in structural biology. Such close collaboration across disciplines allows for rapid testing of new approaches to a given problem.
###
NIAID conducts and supports researchat NIH, throughout the United States, and worldwideto study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at http://www.niaid.nih.gov.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.
NIH...Turning Discovery Into Health
References:
JS McLellan et al. Structure-based design of a fusion glycoprotein vaccine for respiratory syncytial virus. Science DOI: 10.1126/science.1243283 (2013).
JS McLellan et al. Structure of RSV fusion glycoprotein trimer bound to a prefusion-specific neutralizing antibody. Science DOI: 10.1126/science.1234914 (2013).
PUBLIC RELEASE DATE: 31-Oct-2013
ShareContact: Paula Byron
pbyron@vt.edu
540-526-2027
Virginia Tech
Real estate agents emphasize location, location, and once more for good measure location. It's the same in a developing brain, where billions of neurons vie for premium property to make connections. Neurons that stake out early claims often land the best value, even if they don't develop the property until later.
Scientists at the Virginia Tech Carilion Research Institute and the University of Louisville have discovered that during neurodevelopment, neurons from the brain's cerebral cortex extend axons to the edge of the part of the brain dedicated to processing visual signals but then stop. Instead of immediately making connections, the cortical neurons wait for two weeks while neurons from the retina connect to the brain.
Now, in a study to be published in the Nov. 14 issue of the journal Cell Reports, the scientists have discovered how. The retinal neurons stop their cortical cousins from grabbing prime real estate by controlling the abundance of a protein called aggrecan.
Understanding how aggrecan controls the formation of brain circuits could help scientists understand how to repair the injured brain or spinal cord after injury or disease.
"Usually when neuroscientists talk about repairing injured brains, they're thinking about putting neurons, axons, and synapses back in the right place," said Michael Fox, an associate professor at the Virginia Tech Carilion Research Institute and lead author of the study. "It may be that the most important synapses the ones that drive excitation need to get there first. By stalling out the other neurons, they can get the best spots. This study shows that when we think about repairing damaged neural networks, we need to consider more than just where connections need to be made. We also need to think about the timing of reinnervation."
The researchers genetically removed the retinal neurons, which allowed the cortical axons to move into the brain earlier than they normally would.
"We were interested in what environmental molecular cues allow the retinal neurons to control the growth of cortical neurons," said Fox, who is also an associate professor of biological sciences in Virginia Tech's College of Science. "After years of screening potential mechanisms, we found aggrecan."
Aggrecan is a protein that has been well studied in cartilage, bones, and the spinal cord, where it is abundant after injuries. According to Fox, aggrecan may be able to isolate damaged areas of the spinal cord to stop inflammation and prevent further destruction. The downside, however, is that aggrecan inhibits axonal growth, which prevents further repair from taking place.
"Axons see this environment and either stop growing or turn around and grow in the opposite direction," said Fox.
Although it is less studied in the developing brain, aggrecan appears in abundance there. In the new study, the researchers found that retinal neurons control aggrecan in a region that receives ascending signals from retinal cells as well as descending signals from the cerebral cortex.
Once the retinal neurons have made connections, they cause the release of enzymes that break down the aggrecan, allowing cortical neurons to move in.
Fox said it is interesting that the retinal axons can grow in this region of the developing brain, despite the high levels of aggrecan. He suspects that it may be because retinal neurons express a receptor integrin that cortical axons do not express.
###
The study, "A molecular mechanism regulating the timing of corticogeniculate innervation," is by Fox, Jianmin Su, a research assistant professor, and Carl Levy, an undergraduate from Suffolk, Va., all with the Virginia Tech Carilion Research Institute; graduate student Justin Brooks and undergraduate Jessica Wang from Virginia Commonwealth University; and Tania Seabrook, a postdoctoral associate, and William Guido, a professor and the chair of the Department of Anatomical Sciences and Neurobiology, both with the University of Louisville School of Medicine.
Written by Ken Kingery
Share
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
PUBLIC RELEASE DATE: 31-Oct-2013
ShareContact: Paula Byron
pbyron@vt.edu
540-526-2027
Virginia Tech
Real estate agents emphasize location, location, and once more for good measure location. It's the same in a developing brain, where billions of neurons vie for premium property to make connections. Neurons that stake out early claims often land the best value, even if they don't develop the property until later.
Scientists at the Virginia Tech Carilion Research Institute and the University of Louisville have discovered that during neurodevelopment, neurons from the brain's cerebral cortex extend axons to the edge of the part of the brain dedicated to processing visual signals but then stop. Instead of immediately making connections, the cortical neurons wait for two weeks while neurons from the retina connect to the brain.
Now, in a study to be published in the Nov. 14 issue of the journal Cell Reports, the scientists have discovered how. The retinal neurons stop their cortical cousins from grabbing prime real estate by controlling the abundance of a protein called aggrecan.
Understanding how aggrecan controls the formation of brain circuits could help scientists understand how to repair the injured brain or spinal cord after injury or disease.
"Usually when neuroscientists talk about repairing injured brains, they're thinking about putting neurons, axons, and synapses back in the right place," said Michael Fox, an associate professor at the Virginia Tech Carilion Research Institute and lead author of the study. "It may be that the most important synapses the ones that drive excitation need to get there first. By stalling out the other neurons, they can get the best spots. This study shows that when we think about repairing damaged neural networks, we need to consider more than just where connections need to be made. We also need to think about the timing of reinnervation."
The researchers genetically removed the retinal neurons, which allowed the cortical axons to move into the brain earlier than they normally would.
"We were interested in what environmental molecular cues allow the retinal neurons to control the growth of cortical neurons," said Fox, who is also an associate professor of biological sciences in Virginia Tech's College of Science. "After years of screening potential mechanisms, we found aggrecan."
Aggrecan is a protein that has been well studied in cartilage, bones, and the spinal cord, where it is abundant after injuries. According to Fox, aggrecan may be able to isolate damaged areas of the spinal cord to stop inflammation and prevent further destruction. The downside, however, is that aggrecan inhibits axonal growth, which prevents further repair from taking place.
"Axons see this environment and either stop growing or turn around and grow in the opposite direction," said Fox.
Although it is less studied in the developing brain, aggrecan appears in abundance there. In the new study, the researchers found that retinal neurons control aggrecan in a region that receives ascending signals from retinal cells as well as descending signals from the cerebral cortex.
Once the retinal neurons have made connections, they cause the release of enzymes that break down the aggrecan, allowing cortical neurons to move in.
Fox said it is interesting that the retinal axons can grow in this region of the developing brain, despite the high levels of aggrecan. He suspects that it may be because retinal neurons express a receptor integrin that cortical axons do not express.
###
The study, "A molecular mechanism regulating the timing of corticogeniculate innervation," is by Fox, Jianmin Su, a research assistant professor, and Carl Levy, an undergraduate from Suffolk, Va., all with the Virginia Tech Carilion Research Institute; graduate student Justin Brooks and undergraduate Jessica Wang from Virginia Commonwealth University; and Tania Seabrook, a postdoctoral associate, and William Guido, a professor and the chair of the Department of Anatomical Sciences and Neurobiology, both with the University of Louisville School of Medicine.
Written by Ken Kingery
Share
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
NEW YORK (AP) — In her teenage dream? Mick Jagger says he never hit on Katy Perry when she was 18.
During an interview with an Australian radio show this week, the pop star said she sang backing vocals for Jagger's 2004 song "Old Habits Die Hard." Perry said she had dinner with the veteran rocker and that "he hit on me when I was 18."
In a statement Thursday, a representative for Jagger says he "categorically denies that he has ever made a pass at Katy Perry." The rep adds: "Perhaps she is confusing him with someone else."
Perry was one of the singers to make a guest appearance on the Rolling Stones' tour this year. The 29-year-old singer also said in the interview that the 70-year-old Jagger has been "very kind" to her.
