The Key Ingredient to Effective Cancer Treatments

About 50 percent of cancer patients have tumors that are resistant to radiation because of low levels of oxygen?a state known as hypoxia. A startup in San Francisco is developing proteins that could carry oxygen to tumors more effectively, increasing the odds that radiation therapy will help these patients.

Last month, the National Cancer Institute (NCI) gave that startup, Omniox, $3 million in funding. Omniox is collaborating with researchers at the NCI to test whether its oxygen-carrying compounds improve radiation therapy in animals with cancer.

Most tumors have hypoxic regions, and researchers believe they have a significant impact on treatment outcomes in about half of patients. Tumor cells proliferate with such abandon that they outstrip their blood supply, creating regions with very low levels of oxygen. This lack of oxygen drives tumor cells to generate more blood vessels, which metastatic cells use to travel elsewhere in the body and spread the cancer.

Radiation therapy depends on oxygen to work. When ionizing radiation strikes a tumor, it generates reactive chemicals called free radicals that damage tumor cells. Without oxygen, the free radicals are short-lived, and radiation therapy isn't effective. "Radiation treatment is given today on the assumption that tumors are oxygenated" and will be damaged by it, says Murali Cherukuri, chief of biophysics in the Center for Cancer Research at the NCI in Bethesda, Maryland. "Hypoxic regions survive treatment and repopulate the tumor."

Since the 1950s, researchers have tried many ways to get more oxygen into tumors, without success. Having patients breathe high levels of oxygen prior to radiation doesn't work, and developing an agent to carry oxygen through the blood to a tumor has proved very difficult. Artificial proteins that mimic the body's natural oxygen carrier, hemoglobin, can be dangerously reactive?destroying other important chemicals in the blood. And other oxygen carriers tend to either cling to oxygen too tightly or release it too soon, before it gets to the least oxygenated regions of the tumor.

"We're hoping that since most tumors are hypoxic, we could improve the effectiveness of radiation therapy in a large number of people," says Stephen Cary, cofounder and CEO of Omniox. The company has developed a range of proteins that are tailored to hold onto oxygen until they're inside hypoxic tissue. These proteins are not based on hemoglobin, so they don't have the same toxic effects.

The company's technology comes from the lab of Michael Marletta, a professor of chemistry at the University of California, Berkeley. "Most blood substitutes have failed," says Marletta, because they were based on globin proteins, which includes hemoglobin. Hemoglobin is able to work in the body because it's encased in red blood cells. Unprotected, oxygenated globin proteins react with nitric oxide in the blood, destroying the oxygen, the nitric oxide, and the protein itself.

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In Los Angeles, Mayoral Aide Weighs Bid for Higher City Hall Perch

It was the latest example of a City Hall turning to the private sector for assistance navigating public water: think Daniel L. Doctoroff, who held a similar position in New York.

Now, Mr. Beutner says that he may be setting his sights a bit higher ? moving, in effect, from being a Doctoroff to being a Bloomberg.

In an interview this week in his modest 13th-floor office in City Hall, Mr. Beutner said he was thinking of running for mayor when Mr. Villaraigosa?s term expires in 2013, leading some of his colleagues to draw comparisons to another business leader who went into politics, Michael R. Bloomberg.

?I?ve had a few people who have taken notice of what I?m doing and urged me to give some thought to it,? he said. ?I have never run for office. I didn?t take this office intending to run for office, and 2013 is a long time away. I figured I should give it some thought.?

Mr. Beutner, 50, who has lived in Los Angeles for just over 10 years, would certainly not be the first business executive to take a look at government and decide that it is a job he could do (though unlike most others, he has had an inside perch at this City Hall over the past year). And as a rule, the transition from business to campaigning is not easy, as Meg Whitman, the business executive who got crushed after spending over $140 million of her own money running for California governor this year, could tell Mr. Beutner.

At the very least, should Mr. Beutner run, he could inject a new element into an early field that consists so far of fairly well-known Los Angeles public officials who have worked their way up the system. By dint of name recognition, public record and network of connections in political, labor, fund-raising and business circles, any of them could be formidable opponents.

Among those considering a race are Zev Yaroslavsky, a longtime member of the County Board of Supervisors; Wendy Greuel, the city controller; Eric Garcetti, the City Council president; and State Senator Alex Padilla, who represents the city in Sacramento.

Mr. Beutner is strikingly low-key and low-profile (he does not even have his own listing in Wikipedia, though presumably that is about to change). He is given, in conversation, to lapsing into the jargon of government and business; it remains to be seen what kind of strength or spirit he could bring as a candidate.

What is more, his previous career in investment banking? he was a partner at the Blackstone Group, the private equity firm, and a cofounder of Evercore Partners, a boutique investment firm ? would no doubt be closely examined by rivals should he get into the race.

Mr. Beutner was recruited for the City Hall job by Jay Carson, the former Los Angeles chief deputy mayor who now works for Mr. Bloomberg?s private foundation. Mr. Carson said he had been encouraging Mr. Beutner to run.

In theory, at least, Mr. Beutner could use his personal fortune, which has allowed him to retire and work at City Hall for $1 a year, to have a financial advantage. But in the interview, he said that he did not intend to do that, arguing that it was important for a candidate to build a network of financial supporters as a part of an effort to present himself to voters.

?I certainly believe in myself,? he said, ?but I really think it?s important that whoever runs for office be prepared to go through a vetting process, not only community groups, but the media. If you don?t put yourself out there and let voters get a real sense of who you are good or bad, you are not going to win.?

In that sense, barring last-minute changes of heart, he would be different from Mr. Bloomberg, who has never shown a moment?s hesitancy in financing his own campaigns: he has spent well over $200 million in his various races for mayor. (Though it should said that Mr. Bloomberg?s wealth, estimated at close to $18 billion, puts him in a different financial stratosphere than Mr. Beutner.)

Mr. Beutner retired as an investment banker after breaking his neck in an accident while biking on the pitched trails in the Santa Monica Mountains, near his home in Malibu, in 2007. He was born in New York and grew up in Grand Rapids, Mich.

In a suggestion of the kind of argument he might offer should he run, he said that Los Angeles needed someone with broad business experience to help it through a difficult economic time and rebuild its economic base.

?We are facing challenges that this city hasn?t seen since its birth, in my view,? he said. ?We are facing record unemployment, long-range fiscal deficits, great challenges in educating our youths.?

Asked if he had told the current mayor his thinking, he responded, ?If I decide to run, I?ll talk to him.?

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Crowdsourcing Jobs to a Worldwide Mobile Workforce

A few years ago, Nathan Eagle had a big idea. What if millions of people in poor countries?people who couldn't find work in their local economies?could become a remote workforce for organizations all over the world? And what if, instead of traveling to do such jobs at call centers or other outsourcing offices in big cities, they could do their work quickly, reliably, and easily through text messages on their mobile phones?

Eagle founded a small startup, Txteagle, in Cambridge, Massachusetts, to put the idea to the test. It has struck deals with mobile-phone carriers around the world to pay workers in credits for mobile airtime. In many places, that's as good as cash.

But while the concept sounds promising, expanding the business has proved difficult. Eagle told Technology Review this summer that his venture is "going to be binary?a huge hit or a spectacular failure."

One big challenge is to find valuable tasks that can be completed through text messages and phone calls. Eagle got the idea for the company after he created a service that let nurses in the coastal Kenyan village of Kilifi send text messages to tell central blood banks how much blood their hospital had on hand, so its supplies could be refilled more efficiently. Simply compensating the nurses for the cost of their text messages turned out to be the key to its success.

He launched Txteagle in Kenya and eventually had 10,000 people doing part-time tasks such as filling out surveys for international agencies, translating text, or collecting address data for business directories. One of his first partners was Nokia, which paid local people to translate mobile-phone menu functions into the 60 languages used in the country. But that task was quickly exhausted.

Now Txteagle needs to form several solid partnerships with multinational corporations that could supply a steady stream of small tasks. Eagle believes one promising idea is to use Txteagle as a market-research tool: workers could be paid to help companies learn what sorts of products would be desired in their rural corners of the world.

Txteagle recently announced a collaboration with the United Nations, which will use the mobile-phone platform to survey up to 500,000 people in 70 countries about their local governance. That brings the number of countries with Txteagle workers up to 80. The U.N.'s goal is to lay the foundation for future disaster-response efforts by learning how well communities and their governments communicate with each other. People who complete the survey will be paid about $1 and reimbursed for the cost of the text message.

For the U.N. initiative, Txteagle is working with the Global Network for Disaster Reduction, a nonprofit organization that influences policy in more than 90 countries. Most nonprofits operate on a relatively small scale, says Terry Gibson, a project manager at GNDR, but Txteagle allows them to reach a significantly larger audience.

Txteagle isn't the only company exploring ways to crowdsource small tasks to people all over the world. In 2005, Amazon launched its Mechanical Turk project, which sets up a way for a large group of distributed workers to participate in jobs like identifying elements in a set of photographs or performing data entry and transcription. A San Francisco-based startup, CrowdFlower, collaborated with nonprofit organizations this year to have people translate and map text messages that were sent from victims of floods in Pakistan and the earthquake in Haiti. Lukas Beiwald, CEO of CrowdFlower, says his company compensates its workers through PayPal and, in some cases, with virtual currency like the money used in Second Life.

The fundamental technology behind Txteagle includes algorithms for quality control, so that people who do consistently accurate work make higher wages. Workers who recruit others are paid small bonuses. To generate revenue, the company takes a tiny fraction of certain paid transactions.

To make real money with this business model, however, Eagle will need millions of workers using the platform. For now, he estimates, about 100,000 people will be using Txteagle to make money by the end of U.N. survey. And he hopes to find enough partners, with enough of the right sort of small tasks, to push those numbers even higher. "We'd like to be the largest knowledge workforce in the world," he says.

Kate Greene and Nathan Eagle are coauthoring Reality Mining: Using Big Data to Engineer a Better World, to be published by MIT Press.

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Crowdsourcing Jobs to a Worldwide Mobile Workforce

A few years ago, Nathan Eagle had a big idea. What if millions of people in poor countries?people who couldn't find work in their local economies?could become a remote workforce for organizations all over the world? And what if, instead of traveling to do such jobs at call centers or other outsourcing offices in big cities, they could do their work quickly, reliably, and easily through text messages on their mobile phones?

Eagle founded a small startup, Txteagle, in Cambridge, Massachusetts, to put the idea to the test. It has struck deals with mobile-phone carriers around the world to pay workers in credits for mobile airtime. In many places, that's as good as cash.

But while the concept sounds promising, expanding the business has proved difficult. Eagle told Technology Review this summer that his venture is "going to be binary?a huge hit or a spectacular failure."

One big challenge is to find valuable tasks that can be completed through text messages and phone calls. Eagle got the idea for the company after he created a service that let nurses in the coastal Kenyan village of Kilifi send text messages to tell central blood banks how much blood their hospital had on hand, so its supplies could be refilled more efficiently. Simply compensating the nurses for the cost of their text messages turned out to be the key to its success.

He launched Txteagle in Kenya and eventually had 10,000 people doing part-time tasks such as filling out surveys for international agencies, translating text, or collecting address data for business directories. One of his first partners was Nokia, which paid local people to translate mobile-phone menu functions into the 60 languages used in the country. But that task was quickly exhausted.

Now Txteagle needs to form several solid partnerships with multinational corporations that could supply a steady stream of small tasks. Eagle believes one promising idea is to use Txteagle as a market-research tool: workers could be paid to help companies learn what sorts of products would be desired in their rural corners of the world.

Txteagle recently announced a collaboration with the United Nations, which will use the mobile-phone platform to survey up to 500,000 people in 70 countries about their local governance. That brings the number of countries with Txteagle workers up to 80. The U.N.'s goal is to lay the foundation for future disaster-response efforts by learning how well communities and their governments communicate with each other. People who complete the survey will be paid about $1 and reimbursed for the cost of the text message.

For the U.N. initiative, Txteagle is working with the Global Network for Disaster Reduction, a nonprofit organization that influences policy in more than 90 countries. Most nonprofits operate on a relatively small scale, says Terry Gibson, a project manager at GNDR, but Txteagle allows them to reach a significantly larger audience.

Txteagle isn't the only company exploring ways to crowdsource small tasks to people all over the world. In 2005, Amazon launched its Mechanical Turk project, which sets up a way for a large group of distributed workers to participate in jobs like identifying elements in a set of photographs or performing data entry and transcription. A San Francisco-based startup, CrowdFlower, collaborated with nonprofit organizations this year to have people translate and map text messages that were sent from victims of floods in Pakistan and the earthquake in Haiti. Lukas Beiwald, CEO of CrowdFlower, says his company compensates its workers through PayPal and, in some cases, with virtual currency like the money used in Second Life.

The fundamental technology behind Txteagle includes algorithms for quality control, so that people who do consistently accurate work make higher wages. Workers who recruit others are paid small bonuses. To generate revenue, the company takes a tiny fraction of certain paid transactions.

To make real money with this business model, however, Eagle will need millions of workers using the platform. For now, he estimates, about 100,000 people will be using Txteagle to make money by the end of U.N. survey. And he hopes to find enough partners, with enough of the right sort of small tasks, to push those numbers even higher. "We'd like to be the largest knowledge workforce in the world," he says.

Kate Greene and Nathan Eagle are coauthoring Reality Mining: Using Big Data to Engineer a Better World, to be published by MIT Press.

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Are Security Scanners Safe?

As millions of U.S. travelers get ready for the busiest flying day of the year, scientists still can't agree over whether the dose of radiation delivered by so-called backscatter machines is significantly higher than the government says. This is despite months of public debate between the White House, the U.S. Food and Drug Administration, and independent scientists.

Full-body scanners have been installed at many U.S. airports. The machines use either low-energy, millimeter wavelength radiation, which is harmless, or X-rays, which can potentially be hazardous. X-rays can ionize atoms or molecules, which can lead to cancerous changes in cells. Even if the government has significantly underestimated the dose of radiation delivered by an X-ray scanner, it is likely to be relatively small.

The low-energy X-rays emitted by the second type of scanner?also known as a backscatter machine?can pass through clothing but not skin or metal. This makes it possible to spot concealed weapons or explosives, although it also reveals a person, essentially, in the nude. To address this, the U.S. Transportation Security Agency is working on software that converts an image of person into a stick figure, or a blob, without obscuring objects that might pose a security threat. Passengers can also opt to be frisked instead of scanned.

In April, four scientists at the University of California, San Francisco, wrote a public letter to the White House warning that the government may have underestimated the dosage of ionizing radiation delivered to a person's skin from a backscatter machine by one or two orders of magnitude. The scientists, who have expertise in biochemistry, biophysics, oncology, and X-ray crystallography, pointed out that the government's estimate was based on radiation exposure for the entire body. During scanning, the majority of radiation will be focused on the surface of the body, meaning a more concentrated dose of radiation is delivered to the skin.

The Health Physics Society has worked with the FDA to determine the safety of backscatter machines. Spokeswoman Kelly Classic says a dummy made of acrylic is used to measure exposure to ionizing radiation. Sensors attached to the surface of the dummy determine the dose of radiation a person would get from the machine.

The FDA asserts that its method is correct. "This is how we measure the output of X-ray machines and how we've done it for the past 50 years," says Classic.

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DeLay Is Convicted in Texas Donation Case

After 19 hours of deliberation, a jury of six men and six women decided that Mr. DeLay was guilty of conspiring with two associates in 2002 to circumvent a state law against corporate contributions to political campaigns. He was convicted of one charge of money laundering and one charge of conspiracy to commit money laundering.

As the verdict was read, Mr. DeLay, 63, sat stone-faced at the defense table. Then he rose, turned, smiled and hugged his wife and then his weeping daughter in the first row of spectators. He faces between 5 and 99 years in prison, though the judge may choose probation.

A few minutes later, Mr. DeLay said outside the courtroom that he would appeal the decision. He called the prosecution a political vendetta by Democrats in the local district attorney?s office, and revenge for his role in orchestrating the 2003 redrawing of Congressional districts to elect more Republicans.

?This is an abuse of power,? he said. ?It?s a miscarriage of justice. I still maintain my innocence. The criminalization of politics undermines our very system.?

The verdict ends the latest chapter in a long legal battle that forced Mr. DeLay to step down. The trial also opened a window on the world of campaign financing, as jurors heard testimony about large contributions flowing to Mr. DeLay from corporations seeking to influence him, and about junkets to luxury resorts where the congressman would rub shoulders with lobbyists in return for donations.

Rosemary Lehmberg, a Democrat and Travis County district attorney, said the decision to pursue charges had nothing to do with partisan politics.

?This was about holding public officials accountable, that no one is above the law,? she said.

During the three-week trial, the prosecution presented more than 30 witnesses in an effort to prove that Mr. DeLay conspired to circumvent the state law. Since 1903, Texas has prohibited corporations from giving money to candidates directly or indirectly.

Mr. DeLay was initially charged with breaking campaign finance law. But prosecutors later switched strategies because it was impossible under the law at the time to accuse someone of conspiring to break campaign finance rules, prosecutors said.

Instead, prosecutors used a novel legal theory never before tried in Texas: They argued that Mr. DeLay and two of his political operatives ? John Colyandro and Jim Ellis ? had violated the criminal money-laundering law.

They were charged with conspiring to funnel $190,000 in corporate donations to state candidates through the Republican National Committee.

The main facts of the case were never in dispute.

In mid-September 2002, as the election heated up, Mr. DeLay?s state political action committee, Texans for a Republican Majority, gave a check for $190,000 to the Republican National Committee. The money had been donated earlier in the year by various corporate lobbyists seeking to influence Mr. DeLay, several witnesses said.

On Sept. 13, the check was delivered to the R.N.C. by Mr. Ellis, who was Mr. DeLay?s top political operative in Washington and headed his federal political action committee.

At the same meeting, Mr. Ellis also gave the Republican director of political operations, Terry Nelson, a list of state candidates and an amount to be sent to each. Mr. Nelson testified that Mr. Ellis had told him the request for the swap had come from Mr. DeLay.

In early October, donations were sent from a separate account filled with individual donations to seven Republican candidates in Texas. Six of them won. Republicans took control of the Legislature for the first time in modern history and in 2003 pushed through a redistricting plan, orchestrated by Mr. DeLay, that sent more Texas Republicans to Congress in 2004 and helped him consolidate power.

Jurors had to wrestle with the questions of what Mr. DeLay knew about the transaction, when he found out and whether he participated in the decision to swap the money.

This article has been revised to reflect the following correction:

Correction: November 24, 2010

An earlier version of this article had an incorrect time reference. Tom DeLay was convicted on Wednesday.

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Leaked: pictures of Android 2.3 running on the Nexus S

Pictures of the next major version of Android, version 2.3 (codenamed Gingerbread), running on the Samsung Nexus S, have leaked to XDA Developers thanks to an anonymous source. The photos are quite blurry and don't really reveal many new features in Android 2.3, but it's still a significant leak. It means that the Nexus S, the successor to the Nexus One, is coming, and it's coming soon.

As far as specifications of the "thin and curved" device go, XDA Developers speculates the following:

  • ArmV7 CPU Could be Dual Core
  • Open GL ES Supported
  • 512 or 328MB Ram (Not 100% known)
  • 1GB or 2GB Internal Memory (Not 100% known)
  • 800480 Screen Resolution
  • 4? Screen Size
  • SuperAmoled2 Possibly
  • 720P HD Video

Google is expected to make the Nexus S official before the end of the year, meaning the company has five weeks left. Google's Nexus One set the standard for Android devices in 2010, and we're hoping the Nexus S will do the same for the platform in 2011.

Last month, Google put a Gingerbread figure up on campus, which joins other treats already there. The alphabetically ordered deserts in front of the Android building represent the operating system's codenames: version 1.5 (codenamed Cupcake), versions 2.0-2.1 (codenamed clair), and version 2.2 (codenamed Froyo, short for frozen yogurt). Previously, it was believed that version 3.0 was codenamed Gingerbread, version 3.5 was codenamed Honeycomb, and version 4.0 was codenamed Ice Cream. Gingerbread was slated for late 2010, Honeycomb was expected to arrive in early 2011, and Ice Cream was expected somewhere in mid-2011, if not later.

Now, it appears that codename Gingerbread is Android 2.3 and not version 3.0. This throws the whole speculated release schedule out of whack, but in either case, we just want Google to make the official Gingerbread announcement already.

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Wikileaks is down on verge of massive documents dump [Update: Site is back up] [TNW Media]

We just were clued in on Twitter that controversial document leaking website Wikileaks is down hours after sending out the following tweet:

The mirror for the site, however, is still up apparently. Also, a few of the DNS addresses for Wikileaks are unreachable according to this tweet ? we tried the links and went nowhere, but we aren?t sure what the issue is.

This comes just as Wikileaks is about to release a huge number of additional documents that has has the US government talking to allies, and predictably, a number of people on Twitter are suggesting that the US government may have finally done something to shut down the site, though of course right now those are all just conspiracy theories ? the site may just simply be having downtime or the mysterious operators of the site may be prepping it for the release. The tweets are coming in fast and furious (we?re seeing about a hundred or so every minute or two) about the site being down and what it means, and we?ll keep a close eye on this developing story.

Somewhere, Fidel Castro is not happy.

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TiVo keeps bleeding money: Q3 was bad, Q4 could be worse

Digital video recorder maker TiVo has reported its earnings for Q3 2010, which ended on October 31, and the news wasn't good, according to The Wall Street Journal. TiVo, whose set-top boxes were the first to pause, rewind, and record live television, now has just 2.3 million subscribers.

The company lost 112,000 subscribers during the quarter, and nearly 500,000 since last year. Its churn rate, the percentage of customers who cancel their subscriptions each month, rose from 1.7 percent to 2 percent.

Q2 2010 revenue was at $42.1 million while Q3 2009 saw $47.1 million, but in Q3 2010, revenue was only $41.3 million. Furthermore, net losses were at $20.6 million, which is more than triple from last year's quarter ($6.4 million).

TiVo is betting big on technology deals with European providers, like Virgin Media in the UK, Ono in Spain, and Canal in Scandinavia. The company hopes to gain more than 7 million new customers. It's also workin on an iPad app, which will let users search, browse, and discover content without interrupting what they're watching on TV.

TiVo is also experimenting with lower up-front prices and higher subscription rates. This results in higher subscription rates and revenue-per-subscriber, but in the short term, it lowers revenue. The company is also spending more on legal fees, fighting with EchoStar and Dish Network, as well as on research and development. In other words, Q4 will be worse than Q3. The company says it expects revenues from $40 million to $42 million and losses from $32 million to $34 million.

Services like Hulu and Netflix are likely helping TiVo's demise. Right now, it doesn't look as if the company has anything planned that could really turn it around.

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The Key Ingredient to Effective Cancer Treatments

About 50 percent of cancer patients have tumors that are resistant to radiation because of low levels of oxygen?a state known as hypoxia. A startup in San Francisco is developing proteins that could carry oxygen to tumors more effectively, increasing the odds that radiation therapy will help these patients.

Last month, the National Cancer Institute (NCI) gave that startup, Omniox, $3 million in funding. Omniox is collaborating with researchers at the NCI to test whether its oxygen-carrying compounds improve radiation therapy in animals with cancer.

Most tumors have hypoxic regions, and researchers believe they have a significant impact on treatment outcomes in about half of patients. Tumor cells proliferate with such abandon that they outstrip their blood supply, creating regions with very low levels of oxygen. This lack of oxygen drives tumor cells to generate more blood vessels, which metastatic cells use to travel elsewhere in the body and spread the cancer.

Radiation therapy depends on oxygen to work. When ionizing radiation strikes a tumor, it generates reactive chemicals called free radicals that damage tumor cells. Without oxygen, the free radicals are short-lived, and radiation therapy isn't effective. "Radiation treatment is given today on the assumption that tumors are oxygenated" and will be damaged by it, says Murali Cherukuri, chief of biophysics in the Center for Cancer Research at the NCI in Bethesda, Maryland. "Hypoxic regions survive treatment and repopulate the tumor."

Since the 1950s, researchers have tried many ways to get more oxygen into tumors, without success. Having patients breathe high levels of oxygen prior to radiation doesn't work, and developing an agent to carry oxygen through the blood to a tumor has proved very difficult. Artificial proteins that mimic the body's natural oxygen carrier, hemoglobin, can be dangerously reactive?destroying other important chemicals in the blood. And other oxygen carriers tend to either cling to oxygen too tightly or release it too soon, before it gets to the least oxygenated regions of the tumor.

"We're hoping that since most tumors are hypoxic, we could improve the effectiveness of radiation therapy in a large number of people," says Stephen Cary, cofounder and CEO of Omniox. The company has developed a range of proteins that are tailored to hold onto oxygen until they're inside hypoxic tissue. These proteins are not based on hemoglobin, so they don't have the same toxic effects.

The company's technology comes from the lab of Michael Marletta, a professor of chemistry at the University of California, Berkeley. "Most blood substitutes have failed," says Marletta, because they were based on globin proteins, which includes hemoglobin. Hemoglobin is able to work in the body because it's encased in red blood cells. Unprotected, oxygenated globin proteins react with nitric oxide in the blood, destroying the oxygen, the nitric oxide, and the protein itself.

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