SpaceX Dragon capsule makes Easter delivery to space station

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The Dragon cargo ship, operated by the private spaceflight company SpaceX, arrived at the International Space Station on Sunday morning

It's not exactly the Easter bunny, but a commercial Dragon cargo ship built by SpaceX made an Easter delivery to the International Space Station Sunday (April 20) to deliver tons supplies, and possibly even some treats, for the astronauts on board.

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The roboticDragon spacecraftarrived at space station Sunday morning, floating within reach of the orbiting laboratory's robotic arm. Station astronauts used the arm to capture the Dragon spacecraft as both spacecraft sailed 260 miles (418 kilometers) above Egypt and the Nile River.

"Great work catching the Dragon," NASA astronaut Jack Fischer radioed the station crew Mission Control in Houston. The station crew then carefully attached the Dragon cargo ship to a docking port on the station, completing the job in just under three hours. [See photos of SpaceX's Dragon launch and station arrival]

The Hawthorne, Calif.-basedSpaceXlaunched the Dragon cargo ship toward the space station on Friday (April 18) using its own Falcon 9 rocket that lifted off from Cape Canaveral Air Force Station in Florida. The mission is SpaceX's fourth Dragon flight to the space station and third of 12 cargo delivery missions under a $1.6 billion deal with NASA.

The Dragon spacecraft is carrying 5,000 lbs. (2,268 kilograms) of food, supplies and gear for 150 different experiments. A miniature lettuce farm, space robot legs and laser communications system are among the delivery's highlights.

Bill Gerstenmaier, NASA associate administrator for human exploration and operations, said Friday that he wasn't sure if those supplies included any chocolate eggs, jelly beans or other Easter goodies for the station crew.

"It'll be a surprise for all of us when they open the hatch," Gerstenmaier said. That hatch opening is slated to occur on Monday.

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SpaceX Dragon capsule makes Easter delivery to space station

Red Bull pleads innocence in Fallows row

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Red Bull plead innocence in Fallows row

Red Bull maintain that they aren't behind aero chief Dan Fallows' about turn, as the dispute between McLaren and the Milton Keynes outfit heads to the High Court.

McLaren are reportedly planning legal action against Red Bull for encouraging Fallows to break a binding contract with them, although Red Bull Team Principal Christian Horner refuses to acknowledge that the reigning Constructors' Champions did anything wrong.

"The situation with Dan is very clear," Horner told Autosport.

"Dan decided that he was going to leave Red Bull for reasons of his own.

"With the changes that have happened at McLaren [such as Martin Whitmarsh being moved aside], he decided that he didn't want to join.

"It was 100 percent his decision to approach us and see if there was a situation still open.

"It was his choice and I think that getting lawyers involved, if that is the way that McLaren want to act, then that is what will have to be done."

Horner also dismissed the merits of McLaren's legal claim, adding that the Woking outfit would be better off if they were focused on improving their car rather than waste time and money on legal fees.

"It is very easy for McLaren to be drawing focus away from their bigger issues," Horner added.

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Red Bull pleads innocence in Fallows row

Red Bull plead innocence in Fallows row

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Red Bull plead innocence in Fallows row

Red Bull maintain that they aren't behind aero chief Dan Fallows' about turn, as the dispute between McLaren and the Milton Keynes outfit heads to the High Court.

McLaren are reportedly planning legal action against Red Bull for encouraging Fallows to break a binding contract with them, although Red Bull Team Principal Christian Horner refuses to acknowledge that the reigning Constructors' Champions did anything wrong.

"The situation with Dan is very clear," Horner told Autosport.

"Dan decided that he was going to leave Red Bull for reasons of his own.

"With the changes that have happened at McLaren [such as Martin Whitmarsh being moved aside], he decided that he didn't want to join.

"It was 100 percent his decision to approach us and see if there was a situation still open.

"It was his choice and I think that getting lawyers involved, if that is the way that McLaren want to act, then that is what will have to be done."

Horner also dismissed the merits of McLaren's legal claim, adding that the Woking outfit would be better off if they were focused on improving their car rather than waste time and money on legal fees.

"It is very easy for McLaren to be drawing focus away from their bigger issues," Horner added.

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Red Bull plead innocence in Fallows row

F1: Red Bull plays down McLaren row role

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By Jonathan Noble Monday, April 21st 2014, 10:01 GMT

Red Bull insists it played no part in aero chief Dan Fallows' decision to return to its Formula 1 team, as its row with McLaren heads for the High Court.

As AUTOSPORT revealed, McLaren is planning legal action against Red Bull for having, it believes, enticed Fallows to break a binding contract he had with the Woking-based outfit.

But amid high tensions over the matter at the Chinese Grand Prix, Red Bull team principal Christian Horner is adamant his squad did nothing wrong.

"The situation with Dan is very clear," said Horner. "Dan decided that he was going to leave Red Bull for reasons of his own.

"With the changes that have happened at McLaren [such as Martin Whitmarsh being moved aside], he decided that he didn't want to join.

"It was 100 per cent his decision to approach us and see if there was a situation still open.

"It was his choice and I think that getting lawyers involved, if that is the way that McLaren want to act, then that is what will have to be done."

Horner said he was unmoved by McLaren's threat of legal action, but he suggested that his rival would be better off focusing on making its car quicker rather than spending money on lawyers.

"It is very easy for McLaren to be drawing focus away from their bigger issues," he said.

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NASA Selects Commercial Crew Program Manager

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NASA has selected Kathy Lueders as program manager for the agency's Commercial Crew Program (CCP). Lueders, who has served as acting program manager since October 2013, will help keep the nation's space program on course to launch astronauts from American soil by 2017 aboard spacecraft built by American companies.

"This is a particularly critical time for NASA's human spaceflight endeavors as the Commercial Crew Program enters into contract implementation," said William Gerstenmaier, associate administrator for NASAs Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington. "Kathys experience and leadership skills developed during the ISS commercial resupply contract activity will be critical to safely and effectively leading commercial crew transportation activities for NASA."

Lueders, who will be assigned to the agency's Kennedy Space Center in Florida, previously served as the International Space Station Program's transportation integration manager, where she managed commercial cargo resupply services to the space station. Lueders also was responsible for NASA oversight of international partner spacecraft visiting the space station, including the European Space Agency's Automated Transfer Vehicle, the Japanese Space Agency's H-II Transfer Vehicle, and the Russian Federal Space Agency's Soyuz and Progress spacecraft.

"Its exciting to think that Ill be continuing to utilize my background and leadership experience with the International Space Station to help the Commercial Crew Program team and our industry partners execute the next phase," said Lueders.

Lueders began her NASA career at the White Sands Test Facility in New Mexico in 1992, where she managed the Shuttle Orbital Maneuvering System and Reaction Control Systems Depot. She served in numerous positions in the space station program, including the deputy manager for station logistics and maintenance, the vehicle systems integration manager, and the Commercial Orbital Transportation Services integration manager.

Lueders has a Bachelor of Business Administration in Finance from the University of New Mexico and a Bachelor of Science and Master of Science in Industrial Engineering from New Mexico State University.

For more information on NASA's Commercial Crew Program, visit:

http://www.nasa.gov/commercialcrew

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NASA Selects Commercial Crew Program Manager

NASA Mars Orbiter Spies Rover Near Martian Butte

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Mon, Apr 21, 2014

Scientists using NASA's Curiosity Mars rover are eyeing a rock layer surrounding the base of a small butte, called "Mount Remarkable," as a target for investigating with tools on the rover's robotic arm. And this image of the rover at work was captured April 11 by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

The butte stands about 16 feet high. Curiosity's science team refers to the rock layer surrounding the base of Mount Remarkable as the "middle unit" because its location is intermediate between rocks that form buttes in the area and lower-lying rocks that show a pattern of striations.

Depending on what the mission scientists learn from a close-up look at the rock and identification of chemical elements in it, a site on this middle unit may become the third rock that Curiosity samples with its drill. The rover carries laboratory instruments to analyze rock powder collected by the drill. The mission's first two drilled samples, in an area called Yellowknife Bay near Curiosity's landing site, yielded evidence last year for an ancient lakebed environment with available energy and ingredients favorable for microbial life.

The rover's current location, where multiple types of rocks are exposed close together, is called "the Kimberley." Here and, later, at outcrops on the slope of Mount Sharp inside Gale Crater, researchers plan to use Curiosity's science instruments to learn more about habitable past conditions and environmental changes.

(Image provided by NASA)

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Park Systems Presents NanoTechnology Advances Thru Innovative AFM Design by CEO Dr. Sang-il Park at MRS Symposium …

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Santa Clara, CA (PRWEB) April 21, 2014

Park Systems, world leader in atomic force microscopy (AFM) for the semiconductor, material and biological science and data storage markets, announced today that its founder and CEO, Dr. Sang-il Park, will present at the MRS Spring Meeting in San Francisco. The presentation titled Crosstalk Eliminated Atomic Force Microscope and Dimensinal Nanometrology for Inline Manufacturing Control will be given on April 23 at 11am in room 3010, level 3 Moscone West.

Dr. Parks presentation will cover Park Systems exclusive innovative AFM platform developed to eliminate cross-talk between the XY and Z scan enabling 3D non contact mode automatic defect review. Park Systemss unique innovative methodology features non-destructive sample scans and longer tip life. The result not only highly reduces costs but also vastly improves productivity, leading to astounding cost savings for manufacturers.

Park Systems recently achieved a commanding market share in the disc storage market through a focused effort on customer needs and performance requirements. It continues to expand into other industries that demand excellence in nanoscale AFM microscopy. Park is the only AFM enabling nanoscale advances such as the 3D scanning with rotated head and automated defect review, states Keibock Lee, President of Park Systems. We have become the leader in nanotechnology design by constantly outperforming our competition, and creating ways to replace or upgrade AFM equipment and technology that align with the customers objectives of accuracy and productivity.

The MRS Spring Meeting is held at the San Francisco Moscone Center April 21-25. Attendees will find Park Systemss exhibit at booth 517, featuring their full line of automated AFMs. Park Systems executive team of scientific engineers welcomes you to visit their booth for an exciting interactive experience that showcases todays most sophisticated AFM nanotechnology. Parks wide array of products are used in semiconductor, material science, biological science and data storage and are known forrevolutionary design features like True Non-Contact mode which have made Park Systems the fastest growing AFM company in the world.

Park offers many scientifically acknowledged advances in AFM technology which can be seen on the web site at http://www.parkafm.com.

About Park Systems Park Systems serves its customers by providing a complete range of atomic force microscopy (AFM) solutions, backed by its global service and support. Park Systems is the leading nanotechnology solutions provider for nanoscale measurements and systems for both research and industry. The product line of Park Systems reflects its focused strength to help customers achieve the metrology performance that meets the needs and requirements of present and future applications. Since improvements in nano-metrology are key to enabling tomorrow's research, analysis, processing and product manufacturing, the innovative technology and market leadership of Park Systems in the field of nano-metrology will remain as the core competence and market driving force of its future business. Park Systems has its global manufacturing and R&D headquarters in Korea. Parks products are sold and supported worldwide with regional headquarters in the US, Korea, Japan, and Singapore, and distribution partners throughout Europe, Asia, and America. For more information, visit http://www.parkAFM.com.

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Park Systems Presents NanoTechnology Advances Thru Innovative AFM Design by CEO Dr. Sang-il Park at MRS Symposium ...

America's Coming Manufacturing Revolution

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Fracking, robotics, and nanotechnology are poised to transform the industrial sector.

Robots weld Ford Mustangs in Michigan. (Reuters/Rebecca Cook RC)

Hardly a day goes by without an article predicting, lamenting, or celebrating America's decline. The turmoil in Crimea and Syria, the polarized and frequently gridlocked U.S. political system, the deepening income and wealth inequalities in the United States, and the growing clout of rivals like China and Russia are all offered as proof of waning American power.

These weaknesses surely exist, and somelike mounting economic inequalityare truly alarming. But the doomsayers often fail to see the ways in which America is gaining rather than losing global influence. And nowhere is this truer than the manufacturing sector. The combination of lower energy prices, innovative information technologies, and advances in robotics and materials science are powering a manufacturing revolution that will reinvigorate the U.S. economy and make many of its industrial sectors the most competitive in the world.

According to Martin Baily and Barry Bosworth of the Brookings Institution, for the past 50 years industrial production in the U.S. has grown at the same rate or even faster than the economy as a whole. This means that contrary to conventional wisdom, manufacturing has not lost ground in terms of its importance in the U.S. economy. Until 2011, when China inched slightly ahead, the United States boasted the worlds largest manufacturing sector, and it continues to be an industrial powerhouse. The general impression that factories in America are disappearing may be true for some sectors and in some regions and cities, but it is inaccurate in the aggregate. We perceive an industry in decline because the great strides that have been made in efficiency and productivity have not generated a proportional increase in jobs. More is being produced, and fewer workers are needed. Between 2000 and 2010, the United States lost 5.7 million manufacturing jobs.

One reason for these job losses is the economic crisis that began in 2008. But another, more fundamental explanation is the manufacturing industrys uneven growth. Most of the expansion of U.S. manufacturing has taken place in one specific sector: computers and electronics, while the 90 percent of manufacturing outside this branchautomobiles, aviation, appliances or chemicals, for exampleis showing slower growth.

Another issue is the trade deficit. Since the early 1980s, the United States has been importing more manufactured goods than it exports. And in the past decade, most of these imports have come from Asia, and mainly from China. The numbers are striking. In 2000, more than 75 percent of the total U.S. trade deficit in manufactured goods was comprised of the gap between what it imported and exported to Asia. By 2012, this difference represented roughly 100 percent of the deficitmeaning that Asia is the only region in the world from which the U.S. imports more manufactured goods than it exports. Furthermore, while in 2000 trade with China accounted for one-third of Americas manufacturing trade deficit with Asia, by 2012 that share had ballooned to an enormous 72 percent.

The good news is that American manufacturing is on the verge of dramatic change. According to Baily and Bosworth, major revolutions are underway in energy, robotics, materials, and applied information technology.

The changes taking place in the energy sector are huge. The United States has the second-largest shale-gas reserves in the world and has pioneered the development of new technologies to exploit it. Fracking, in which gas and oil is extracted from shale rocks by fracturing them, is driving an energy boom in the U.S. that will soon lower natural-gas prices to well below the world average, thus giving American manufacturers a unique competitive advantage.

The automation and robotization of manufacturing plants will further increase efficiency and precision. As robotic capabilities continue to expand, the cost to produce them is shrinking. The downside, of course, is that this will have serious repercussions for job creation, as these machines are likely to displace many workers. America's dominance in computing and electronics gives it a unique edge in the automation of manufacturing processes.

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Margaret Ellen Moores passes at 108

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Published on April 21, 2014 Rushoon native was provinces oldest living person

Rushoon native Margaret Ellen Moores passed away Saturday at the age of 108.

Paul Herridge Photo

Rushoon native Margaret Ellen Moores passed away Saturday at the age of 108.Known affectionately as Aunt Maggie, she was the oldest living resident of Newfoundland and Labrador. In 2011, she spoke to The Southern Gazette about Christmases when she was growing up and is pictured with a doll she received as a child.

Known affectionately as Aunt Maggie, she was the oldest living resident of Newfoundland and Labrador.

Born on Nov. 5, 1905, Mrs. Moores had lived with her daughter and son-in-law Marie and Patrick Cheeseman at their Rushoon home for the last 23 years.

When she was 17, Mrs. Moores moved to St. Johns and spent two years working there. She returned and married Arch Moores, a fisherman, shortly after. Together, the couple had four daughters, one who died as an infant.

Mrs. Moores was an active volunteer in the community in her younger years and at one time taught night school in Rushoon.

Visitation is taking place today and tomorrow at Rushoons Christ The King Roman Catholic Church. Funeral services are scheduled for Wednesday morning at 11 a.m.

Organizations: Christ The King Roman Catholic Church

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Malfunction in molecular 'proofreader' prevents repair of UV-induced DNA damage

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PUBLIC RELEASE DATE:

21-Apr-2014

Contact: Anita Srikameswaran srikamav@upmc.edu 412-578-9193 University of Pittsburgh Schools of the Health Sciences

PITTSBURGH, April 21, 2014 Malfunctions in the molecular "proofreading" machinery, which repairs structural errors in DNA caused by ultraviolet (UV) light damage, help explain why people who have the disease xeroderma pigmentosum (XP) are at an extremely high risk for developing skin cancer, according to researchers at the University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute (UPCI). Their findings will be published this week in the early online version of the Proceedings of the National Academy of Sciences.

Previous research has shown that a DNA-repair protein called human UV-damaged DNA-binding protein, or UV-DDB, signals for a repair when two UV-DDB molecules bind to the site of the problem, said senior investigator Bennett Van Houten, Ph.D., the Richard M. Cyert Professor of Molecular Oncology, Pitt School of Medicine, and co-leader of UPCI's Molecular and Cell Biology Program.

"Our new study shows UV-DDB makes stops along the DNA strand and transiently attaches to it, causing a proofreading change in the protein's conformation, or shape. If the DNA is damaged the protein stays, if the DNA is not damaged the protein leaves," Dr. Van Houten said. "When it comes to a spot that has been damaged by UV radiation, two molecules of UV-DDB converge and stay tightly bound to the site, essentially flagging it for the attention of repair machinery."

The researchers followed the trail of single molecules of UV-DDB by tagging them with light-emitting quantum dots, enabling them to watch the molecules jump from place to place in real time on both normal and UV-exposed DNA strands.

They also tracked a mutant UV-DDB protein associated with XP, an inherited, incurable disease of light sensitivity that affects about 1 in 250,000 people. They found that the mutant UV-DDB molecules are still capable of binding to DNA, but continued to slide along the DNA rather than staying put to signal where the fix was needed.

"Without this important damage control, UV-induced errors could accumulate to cause cell alterations that foster cancer development," Dr. Van Houten said. "Like a bus with no brakes, the XP-associated UV-DDB complex stays on the road and sees possible passengers, but keeps going past the stop."

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Ginseng can treat and prevent influenza and RSV, researcher finds

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21-Apr-2014

Contact: LaTina Emerson lemerson1@gsu.edu 404-413-1353 Georgia State University

ATLANTA--Ginseng can help treat and prevent influenza and respiratory syncytial virus (RSV), a respiratory virus that infects the lungs and breathing passages, according to research findings by a scientist in Georgia State University's new Institute for Biomedical Sciences.

In a recent issue of Nutrients and an upcoming publication of the International Journal of Molecular Medicine, Sang-Moo Kang reports the beneficial effects of ginseng, a well-known herbal medicine, on human health.

Kang's primary research focuses on designing and developing effective vaccines against viral diseases such as influenza virus and RSV, but he partnered with a university and research institutes in South Korea that wanted international collaborative projects to study if ginseng can be used to improve health and protect against disease because of the potential benefit in fighting these viruses. Ginseng has been reported to have anticancer, anti-inflammatory and immune modifying abilities.

Seasonal influenza is a serious respiratory disease that causes annual epidemics in humans worldwide, resulting in about three to five million cases of severe illness and about 250,000 to 500,000 deaths, according to the World Health Organization. Influenza can spread quickly, and new, unexpected pandemic influenza viruses may emerge at any time and cross over to different species. The H1N1 influenza virus, a new strain known as swine flu that emerged in 2009, spread rapidly to more than 74 countries. There are also challenges with existing influenza vaccines, such as required annual updates and no protection against pandemic strains and bird flu.

In addition, there are no vaccines available for RSV, which affects millions and is the leading cause of inflammatory bronchiolitis pneumonia and viral death in infants and in some elderly adults.

In his study published in Nutrients, Kang investigated whether red ginseng extract has preventive effects on influenza A virus infection. He found that red ginseng extract improves the survival of human lung epithelial cells infected with influenza virus. Also, treatment with red ginseng extract reduced the expression of genes that cause inflammation.

After infection with influenza A virus, mice that were orally administered ginseng over a long time showed multiple immune modifying effects, such as stimulated antiviral production of proteins important in immune response and fewer inflammatory cells in their bronchial walls. The study indicates the beneficial effects of red ginseng extract on preventing influenza A virus infections could result from immune modifying capabilities of ginseng.

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Ginseng can treat and prevent influenza and RSV, researcher finds

Transcending the typical sci-fi flick: The PHOENIX chats with Wally Pfister

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I expected Transcendence to be action-packed, futuristic and scientifically fictitious. I anticipated big, nerdy words related to artificial intelligence that I couldnt comprehend, phenomenal acting by Johnny Depp and brilliant graphics on screen.

I did not, however, expect a heart-wrenching story of human love and loss, or to leave the theater with a pit in my stomach and questions of human nature racing through my mind.

Transcendence somehow manages to tell the romantic, age-old story of the human experience in a scarily believable science-fiction setting in a way that doesnt make me feel like a complete sci-fi nerd. With striking acting and conceivable futuristic technology, the film touches its viewers to the core and forces us to question the path our society is headed down.

While it may seem far-off and implausible at first, the film certainly hits close to home. As the anti-technology villainous group in the movie explained, universal mayhem begins with people prioritizing their phones and iPads over other living, breathing humans. It begins where we are right now.

In a phone interview with Transcendence director Wally Pfister, (previously the cinematographer of The Dark Knight and Inception) The PHOENIX gained insight into the making of the film and the intention behind it.

Transcendence is Pfisters directorial debut, and he explained some of the challenges and creative aspects required in making the film come together.

For me, the greatest challenge was also one of the most enlightening, wonderful, fun things, which was in directing actors and delving in the performance for the first time, he said. I really found it extraordinarily fun, but there were challenges because you are suddenly playing the role of psychologist for the first time versus being a cinematographer, which is really just about telling stories with images.

Although its the first movie he has directed, Pfister is already getting the chance to work with renowned actors such as Depp and Morgan Freeman.

Its mind-blowing I feel incredibly fortunate to be lucky enough to have the likes of these incredible actors. And honestly, you know, this isnt just bullshit. They were all a joy to work with.

Obviously Transcendence is a scientific-fiction film, as the main focus and conflict is an artificially intelligent machine, but Pfister emphasized that it differs from typical sci-fi films.

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Transcending the typical sci-fi flick: The PHOENIX chats with Wally Pfister

Penn Medicine researchers uncover hints of a novel mechanism behind general anesthetic action

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PUBLIC RELEASE DATE:

21-Apr-2014

Contact: Lee-Ann Donegan leeann.donegan@uphs.upenn.edu 215-349-5660 University of Pennsylvania School of Medicine

(PHILADELPHIA) Despite decades of common use for surgeries of all kinds, the precise mechanism through which general anesthesia works on the body remains a mystery. This may come as a surprise to the millions of Americans who receive inhaled general anesthesia each year. New research led by the Perelman School of Medicine at the University of Pennsylvania investigated the common anesthetic sevoflurane and found that it binds at multiple key cell membrane protein locations that may contribute to the induction of the anesthetic response. Their findings will appear online in PNAS (Proceedings of the National Academy of Science).

Previous studies have suggested that inhaled general anesthetics such as sevoflurane might work by inactivating sodium channels, specialized protein conduits that open in response to stimuli, like voltage changes, and allow sodium ions to cross the cell membranes of nerve cells. Despite the physiological importance of sodium channels and their possible role as general anesthetic targets, little is known about interaction sites or the mechanism of action.

Penn's Roderic Eckenhoff, MD, vice chair for Research and the Austin Lamont Professor of Anesthesiology and Critical Care leads a team of top medicine, chemistry, and biology researchers who were recently awarded an NIH grant to unravel the mysteries of anesthesia. This paper represents the team's most recent findings.

Researchers found that sevoflurane's interaction with sodium channels plays an essential role in the generation of the electrical impulses necessary for the communication between nerve cells in the brain. "We sought to understand the molecular basis of the interaction of sevoflurane with the sodium channel as a starting point to determine how similar anesthetics might elicit the anesthetic response," says the study's lead author, Annika Barber, PhD, a post-doctoral researcher in the department of Neuroscience at the Perelman School of Medicine at the University of Pennsylvania. At the time the research was conducted, she was a doctoral candidate at Thomas Jefferson University in Philadelphia.

In concert with the Institute for Computational Molecular Science of Temple University, Dr. Barber first used molecular dynamic simulation, a 3-D computer modeling method, to visualize possible interactions of sevoflurane with discrete parts of the bacterial sodium channel called NaChBac. This archetypal membrane protein is homologous to sodium channels found in human brain. "Given the physical and chemical properties of inhaled anesthetics, we expected binding to many possible sites; simulation, however, helped us limit and identify the sites where the binding of sevoflurane might actually change the function of the sodium channel," explained Barber. The team found three key binding sites possibly linked to the anesthetic response. The first involves the channel's sodium pore itself, which is plugged by sevoflurane; the second concerns the gate that governs opening and closing of the sodium channel in response to a voltage change across the membrane of a neuron; and the third surrounds a second gate that controls sodium flow by changing the shape of the channel's narrow pore. These three sites, researchers hypothesize, work together to turn off firing of electrical impulses in key neurons and thus, induce the anesthetic state.

The Jefferson researchers validated the functional significance of these sites by directly measuring the activity of the sodium channel and conducting additional computer simulations. They found that low doses of sevoflurane made voltage-dependent activation of the sodium channel more favorable. This surprising action could explain the excitatory phase many patients experience during the onset of sevoflurane anesthesia. However, as the concentrations of the anesthetic increased, sevoflurane begins to block the sodium channel which might ultimately contribute to the state of anesthesia. These dose-dependent mutually antagonistic effects, in a single ion channel were surprising to the group, and emphasize the complexity of anesthetic action.

"Precisely how these interactions at one ion channel fit into the global effects of anesthesia remains to be seen," says Barber, and adds "this study paves the way to map relevant general anesthetic binding sites in sodium channels and helps understand how their modulation by sevoflurane might determine the physiological processes implicated in general anesthesia".

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Penn Medicine researchers uncover hints of a novel mechanism behind general anesthetic action