Biophysicists measure mechanism that determines fate of living cells

May 23, 2013 ? A new tension gauge tether (TGT) laboratory method developed at the University of Illinois at Urbana-Champaign has broad applications for research into stem cells, cancer, infectious disease, and immunology.

Cells in the human body do not function in isolation. Living cells rely on communication with their environment -- neighboring cells and the surrounding matrix -- to activate a wide range of cellular functions, including reproduction of new cells, differentiation of stem cells into distinct cell types, cell adhesion, and migration of white blood cells to fight bodily infections. This cellular communication occurs on the molecular level and it is reciprocal: a cell receives cues from and also transmits function-activating cues to its neighbors.

The mechanics of this type of cellular interaction have been studied extensively: receptors extending through the cell membrane are activated when they form a bond to specific molecules. Now for the first time, University of Illinois biophysicists at the Center for the Physics of Living Cells and the Institute for Genomic Biology have measured the molecular force required to mechanically transmit function-regulating signals within a cell.

The new laboratory method, named the tension gauge tether (TGT) approach, developed by Taekjip Ha with postdoctoral researcher Xuefeng Wang, and reported in the May 24, 2013, issue of the journal Science, has made it possible to detect and measure the mechanics of the single-molecule interaction by which human cell receptors are activated. The researchers used integrin, a cell membrane receptor protein that is activated when it bonds to a ligand molecule.

In the TGT approach, Ha and Wang repurposed DNA strands, using them as tethers for ligand molecules, to test the tension required to activate cell adhesion through integrin. The integrin bonds to the tethered ligand, and adhesion is activated only if the DNA tether does not rupture.

Taking advantage of the geometric characteristics of DNA's double helix form, the researchers were able to tune the strands to rupture at discrete tension levels: by varying the attachment points along the DNA strands, the force required for rupture was either low (unzipping the helix), high (shearing the strands), or intermediary (combination of unzipping and shearing).

"If you went fishing and a fish broke your 30-lb fishing line but not the 40-lb one, you would know that its strength was in the range of 30?-40 pounds," explained Wang. "Here we applied the same strategy to measure the molecular tension applied by cells (the fish). Mammalian cells apply a force to activate cell membrane proteins called integrins which mediate cell adhesion. We immobilized ligand molecules (the bait) on a surface through molecular tethers (the fishing line) with defined tension tolerances, tunable from 10 pico Newton (pN) to 60 pN). After integrin-ligand binding, cells apply a force on the bonds, and we compare this force to the molecular tether strength by observing cell adhesion status."

Since single-molecule interactions are difficult to monitor, the researchers observed the receptor-regulated cellular function, to gauge whether the integrin was activated. Ha and Wang discovered that integrin experiences a well-defined "quantum of force," about 40 pico-Newton (pN), to activate cell's adhesion to a surface.

"We observed that mammalian cells adhere on the culture surface with 43 pN tension tolerance of ligands, but not on 33 pN surface. Therefore we deduced that single molecular tension is around 40 pN on integrin cell-membrane receptors during cell adhesion," Wang added.

"This is a very exciting result," commented Ha, an Edward William and Jane Marr Gutgsell Endowed Professor at Illinois. "With the ability to define the single molecular forces required to make living cells behave as desired, we may be one step closer to a remedy for certain hard-to-cure diseases. We know that the behavior of cancer cells and stem cells can be controlled by how stiff or soft their environments are. Understanding and manipulating molecular conversation through defined forces has huge implications for the development of future medical interventions. We expect the TGT approach will have broad applications in laboratory studies of cell differentiation, cancer metastasis, as well as immunology and infectious disease."

This research was funded by the National Science Foundation through the Physics Frontiers Center Program (0822613). In addition to his appointment at the University of Illinois, Taekjip Ha is an investigator with the Howard Hughes Medical Institute.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/most_popular/~3/23f8HDeLow4/130523143735.htm

Big Bird Adam Greenberg Fall Leaves Jim Lehrer 666 Park Avenue Kara Alongi Sahara Davenport

Czech police search for American suspected of killing family

PRAGUE (Reuters) - Police are searching for an American man suspected of killing four members of a family in the Czech Republic's second-largest city Brno, police said on Thursday.

Police spokeswoman Petra Vedrova said the suspect may be armed and dangerous. Police had taken measures to stop him from leaving the country and were in contact with neighboring states.

"(The suspect) goes by the name Kevin Dahlgren on social networks, lives in California and speaks only English," the police website said.

The victims were a family but Vedrova declined to give any further details. The man, who police believe is 20-years-old, is the only suspect.

(Reporting by Jason Hovet; Editing by Angus MacSwan)

Source: http://news.yahoo.com/czech-police-search-american-suspected-killing-family-101012798.html

shroud of turin the borgias the masters warren sapp i robot the big c the visitor

Doctors save Ohio boy by 'printing' an airway tube

In a medical first, doctors used plastic particles and a 3-D laser printer to create an airway splint to save the life of a baby boy who used to stop breathing nearly every day.

It's the latest advance from the booming field of regenerative medicine, making body parts in the lab.

In the case of Kaiba (KEYE'-buh) Gionfriddo, doctors didn't have a moment to spare. Because of a birth defect, the little Ohio boy's airway kept collapsing, causing his breathing to stop and often his heart, too. Doctors in Michigan had been researching artificial airway splints but had not implanted one in a patient yet.

In a single day, they "printed out" 100 tiny tubes, using computer-guided lasers to stack and fuse thin layers of plastic instead of paper and ink to form various shapes and sizes. The next day, with special permission from the Food and Drug Administration, they implanted one of these tubes in Kaiba, the first time this has been done.

Suddenly, a baby that doctors had said would probably not leave the hospital alive could breathe normally for the first time. He was 3 months old when the operation was done last year and is nearly 19 months old now. He is about to have his tracheotomy tube removed; it was placed when he was a couple months old and needed a breathing machine. And he has not had a single breathing crisis since coming home a year ago.

"He's a pretty healthy kid right now," said Dr. Glenn Green, a pediatric ear, nose and throat specialist at C.S. Mott Children's Hospital of the University of Michigan in Ann Arbor, where the operation was done. It's described in Thursday's New England Journal of Medicine.

Independent experts praised the work and the potential for 3-D printing to create more body parts to solve unmet medical needs.

"It's the wave of the future," said Dr. Robert Weatherly, a pediatric specialist at the University of Missouri in Kansas City. "I'm impressed by what they were able to accomplish."

So far, only a few adults have had trachea, or windpipe transplants, usually to replace ones destroyed by cancer. The windpipes came from dead donors or were lab-made, sometimes using stem cells. Last month, a 2-year-old girl born without a windpipe received one grown from her own stem cells onto a plastic scaffold at a hospital in Peoria, Ill.

Kaiba had a different problem ? an incompletely formed bronchus, one of the two airways that branch off the windpipe like pant legs to the lungs. About 2,000 babies are born with such defects each year in the United States and most outgrow them by age 2 or 3, as more tissue develops.

In severe cases, parents learn of the defect when the child suddenly stops breathing and dies. That almost happened when Kaiba was 6 weeks old at a restaurant with his parents, April and Bryan Gionfriddo, who live in Youngstown, in northeast Ohio.

"He turned blue and stopped breathing on us," and his father did CPR to revive him, April Gionfriddo said.

More episodes followed, and Kaiba had to go on a breathing machine when he was 2 months old. Doctors told the couple his condition was grave.

"Quite a few of them said he had a good chance of not leaving the hospital alive. It was pretty scary," his mother said. "We pretty much prayed every night, hoping that he would pull through."

Then a doctor at Akron Children's Hospital, Marc Nelson, suggested the experimental work in Michigan. Researchers there were testing airway splints made from biodegradable polyester that is sometimes used to repair bone and cartilage.

Kaiba had the operation on Feb. 9, 2012. The splint was placed around his defective bronchus, which was stitched to the splint to keep it from collapsing. The splint has a slit along its length so it can expand and grow as the child does ? something a permanent, artificial implant could not do.

The plastic is designed to degrade and gradually be absorbed by the body over three years, as healthy tissue forms to replace it, said the biomedical engineer who led the work, Scott Hollister.

Green and Scott Hollister have a patent pending on the device and Hollister has a financial interest in a company that makes scaffolds for implants.

Dr. John Bent, a pediatric specialist at New York's Albert Einstein College of Medicine, said only time will tell if this proves to be a permanent solution, but he praised the researchers for persevering to develop it.

"I can think of a handful of children I have seen in the last two decades who suffered greatly ... that likely would have benefited from this technology," Bent said.

___

Marilynn Marchione can be followed at http://twitter.com/MMarchioneAP

Source: http://news.yahoo.com/doctors-save-ohio-boy-printing-125228957.html

Andy Griffith joe johnson scientology Wimbledon 2012 TV Schedule fourth of july IFE Fireworks 2012 4th Of July

Pure Android version of Samsung Galaxy S4 will initially only be available in the US

We know that much of the world was intrigued when Google announced the forthcoming Samsung Galaxy S4 running stock Android.

We know that interest was still piqued even after the price was announced too, $649 (and yes, the auditorium did get very quiet when the price was announced). Hardware aside, that may prove to be a tougher sell when a 16GB Nexus 4 costs roughly half that.

Still, we expect this ?Google Experience? or ?Nexus user experience? Galaxy S4 will sell rapidly when it launches on June 26th in the United States only. For those outside the US, fret not, Google will most certainly expand market availability, but we do not know if it will be as far reaching as where the current Nexus line-up is available.

If we had to gander a guess, there are two forces at work in that regard. First is LTE radios, it may not be practical to devote niche manufacturing to accommodate all markets. Next is Samsung, who has just launched its flagship device with all the trimmings of TouchWhiz and S-applications and so-forth, the culmination of significant development and investment in Samsung?s own image. So even if this pure-Android SGS4 expands availability outside the US, we doubt it will have the reach of the Nexus line of devices.

Meanwhile, if you are stewing in envy over the prospect remember, there will most definitely be enterprising individuals looking to fleece the desperate of their hard-earned Pounds and Euros on eBay. Or, you can still pick up a thoroughly capable Nexus 4 for a fraction of the price.

source: CNET UK

Source: http://www.phonearena.com/news/Pure-Android-version-of-Samsung-Galaxy-S4-will-initially-only-be-available-in-the-US_id43273

lindzi cox bachelor finale courtney robertson ben flajnik hunger games premiere red meat bachelor ben

How Will 'Nymphomaniac' Make Explicit Shia LaBeouf Sex Scene Safe For Theaters?

Lars von Trier had his actors get down and dirty in his new sexually charged movie "Nymphomaniac." Fans can expect to see the film's stars like Shia LaBeouf, Uma Thurman and Stellan Skarsgard take part in graphic sex scenes with one another when the film finally hits theaters. Except they won't actually be having sex, [...]

Source: http://moviesblog.mtv.com/2013/05/21/nymphomaniac-shia-labeouf-sex-scene/

elisabeth hasselbeck Mothers Day 2013 World Baseball Classic time change Joy Behar Hangover 3 Red Widow

A new crop of domestic mavens

Actresses like Gwyneth Paltrow and Jessica Alba are pursuing new careers as lifestyle gurus.

By Chris Gaylord,?Staff writer / May 22, 2013

Gwyneth Paltrow: the queen bee of a new generation.

Mario Anzuoni/Reuters

Enlarge

Both Martha Stewart and Oprah Winfrey have watched their media empires dwindle. But in their place has risen a new breed of celebrity homemaker ? semiretired actresses enjoying a second career as lifestyle gurus.

Skip to next paragraph

' + google_ads[0].line2 + '
' + google_ads[0].line3 + '

'; } else if (google_ads.length > 1) { ad_unit += ''; } } document.getElementById("ad_unit").innerHTML += ad_unit; google_adnum += google_ads.length; return; } var google_adnum = 0; google_ad_client = "pub-6743622525202572"; google_ad_output = 'js'; google_max_num_ads = '1'; google_feedback = "on"; google_ad_type = "text"; // google_adtest = "on"; google_image_size = '230x105'; google_skip = '0'; // -->

Subscribe Today to the Monitor

Click Here for your FREE 30 DAYS of
The Christian Science Monitor
Weekly Digital Edition

Jessica Alba has not appeared in a live-action, widely released movie since 2011. In that time, she?s launched a line of eco-friendly baby products and published a new book, ?The Honest Life,? about her organic lifestyle.

Blake Lively?s big role in the teen hit ?Gossip Girl? has come to an end and her would-be summer blockbusters ? ?The Green Lantern? and ?Savages? ? fizzled at the box office. Now, the actress has grabbed headlines for taking cooking lessons at Le Cordon Bleu in Paris and installing a massive kitchen in her new home.

But the queen bee of this new era has been Gwyneth Paltrow. During a slow period in her career, she kicked off the online news-letter Goop. While critics mock the website for its casual excess ($100 shirts for babies and four-figure handbags), Goop has secured a place among the big style and parenting blogs. In April, Ms. Paltrow released her second health-minded cookbook, ?It?s All Good.?

?In the ?90s, when celebrities wanted to resuscitate their careers, they would create a perfume,? says Deborah Jaramillo, assistant professor of film and television at Boston University. ?Now, they are taking a more domestic route. They?re positioning themselves as a Martha or Oprah for their own generation.?

Ms. Alba and Ms. Lively are not the first stars to trade in low-cut outfits for aprons. In the 1940s and ?50s, under the constant watch of the moralistic Motion Picture Production Code, Hollywood studios would arrange for sexier, edgier stars to appear in magazines talking about their homes and offering parenting tips.

Today?s tastemakers may be more concerned with demographics. As Alba and Lively have gotten older, so has their key audience. Alba?s new book spends several chapters talking directly to young mothers, the exact group that Ms. Stewart and Ms. Winfrey have had trouble reaching. Throughout those pages, ?The Honest Life? adopts a strong theme of generational responsibility ? a Millennial push to curb the use of chemicals in food and body products.

?I?m intrigued by this idea that we?ve moved into a time when women are portrayed as being more socially conscious and not just fixated on babies and cooking,? says Ms. Jaramillo. ?Whether you agree or disagree with organic foods and organic lifestyles, there is something positive about the message, even if it is still consumer based.?

Source: http://rss.csmonitor.com/~r/feeds/csm/~3/bPzhw7SS9s0/A-new-crop-of-domestic-mavens

adrienne bailon yelp stock honda classic news channel 5 nashville weather jason varitek andrew breitbart dead

Going green: U.S. equipped to grow serious amounts of pond scum for fuel

May 21, 2013 ? A new analysis shows that the nation's land and water resources could likely support the growth of enough algae to produce up to 25 billion gallons of algae-based fuel a year in the United States, one-twelfth of the country's yearly needs.

The findings come from an in-depth look at the water resources that would be needed to grow significant amounts of algae in large, specially built shallow ponds. The results were published in the May 7 issue of Environmental Science and Technology, published by the American Chemical Society.

"While there are many details still to be worked out, we don't see water issues as a deal breaker for the development of an algae biofuels industry in many areas of the country," said first author Erik Venteris of the Department of Energy's Pacific Northwest National Laboratory.

For the best places to produce algae for fuel, think hot, humid and wet. Especially promising are the Gulf Coast and the Southeastern seaboard.

"The Gulf Coast offers a good combination of warm temperatures, low evaporation, access to an abundance of water, and plenty of fuel-processing facilities," said hydrologist Mark Wigmosta, the leader of the team that did the analysis.

Wooing algae as fuel

Algae, it turns out, are plump with oil, and several research teams and companies are pursuing ways to improve the creation of biofuels based on algae -- growing algae composed of more oil, creating algae that live longer and thrive in cooler temperatures, or devising new ways to separate out the useful oil from the rest of the algae.

But first, simply, the algae must grow. The chief requirements are sunlight and water. Antagonists include clouds, a shortage of water, and evaporation.

A previous report by the same team looked mainly at how much demand algae farms would create for freshwater. That report demonstrated that oil based on algae have the potential to replace a significant portion of the nation's oil imports and drew the attention of President Obama.

The new report focuses on actual water supplies and looks at a range of possible sources of water, including fresh groundwater, salty or saline groundwater, and seawater. The team estimates that up to 25 billion gallons of algal oil could be produced annually, an increase of 4 billion gallons over the previous study's estimate. The new amount is enough to fill the nation's current oil needs for one month -- about 600 million barrels -- each year. The study's authors note that the new estimate is exactly that -- an estimate -- based to some degree on assumptions about land and water availability and use.

"I'm confident that algal biofuels can be part of the solution to our energy needs, but algal biofuels certainly aren't the whole solution," said Wigmosta. Most important, he notes that the cost of making the fuel far exceeds the cost of traditional gasoline-based products right now.

Big ponds, big potential

An algae farm would likely consist of many ponds, with water maybe six to 15 inches deep. A few companies have built smaller algae farms and are just beginning to churn out huge amounts of algae to convert to fuel; earlier this year, one company sold algae-based oil to customers in California. Players in the algae biofuels arena range from Exxon-Mobil, which launched a $600 million research effort four years ago, to this year's teenage winner of the Intel Science Talent Search, who was recognized for her work developing algae that produce more oil than they normally do.

The availability of water has been one of the biggest concerns regarding the adoption of broad-scale production of algal biofuel. Scientists estimate that fuel created with algae would use much more water than industrial processes used to harness energy from oil, wind, sunlight, or most other forms of raw energy. To produce 25 billion gallons of algae oil, the team estimates that the process annually would require the equivalent of about one-quarter of the amount of water that is now used each year in the entire United States for agriculture. While that is a huge amount, the team notes that the water would come from a multitude of sources: fresh groundwater, salty groundwater, and seawater.

For its analysis, the team limited the amount of freshwater that could be drawn in any one area, assuming that no more than 5 percent of a given watershed's mean annual water flow could be used in algae production. That number is a starting point, says Venteris, who notes that it's the same percentage that the U.S. Environmental Protection Agency allows power plants to use for cooling.

"In arid areas such as the Desert Southwest, 5 percent is probably an overstatement of the amount of water available, but in many other areas that are a lot wetter, such as much of the East, it's likely that much more water would be available," says Venteris.

"While the nation's Desert Southwest has been considered a possible site for vast algae growth using saline water, rapid evaporation in this region make success there more challenging for low- cost production," Venteris added.

Venteris and colleagues weighed the pluses and minuses of the various water sources. They note that freshwater is cheap but in very limited supply in many areas. Saline groundwater is attractive because it's widely available but usually at a much deeper depth, requiring more equipment and technology to pump it to the surface and make it suitable for algae production. Seawater is plentiful, but would require much more infrastructure, most notably the creation of pipelines to move the water from the coast to processing plants.

The team notes that special circumstances, such as particularly tight water restrictions in some areas or severe drought or above-average rainfall in others, could affect its estimates of water availability.

The work was funded by the DOE's Office of Energy Efficiency and Renewable Energy. In addition to Venteris and Wigmosta, PNNL scientists Richard Skaggs and Andre Coleman contributed to the project and authored the study.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/top_environment/~3/Z4rjrZ05yEQ/130521140916.htm

ozzie guillen buster posey eric holder eric holder carole king crystal renn matilda