Archive for 7 de February de 2017

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Scientists have weaponized human skin to fight a deadly form of brain cancer (in mice)

Human skin can be morphed into genetically modified, cancer-killing brain stem cells, according to a new study. This latest advance has only been tested in mice — but eventually, it’s possible that it could be translated into a personalized treatment for people with a deadly form of brain cancer.

The study builds on an earlier discovery that brain stem cells have a weird affinity for cancers. So researchers, led by Shawn Hingtgen, a professor at University of North Carolina at Chapel Hill, created genetically engineered brain stem cells out of human skin. Then they armed the stem cells with drugs to squirt directly onto the tumors of mice that had been given a human form of brain cancer. The treatment shrank the tumors and extended survival of the mice, according to results recently published in the journal Science Translational Medicine.

Usually we think about stem cell therapy in the context of rebuilding or regrowing a broken body part — like a spinal cord. But if they could be modified to become cancer-fighting homing missiles, it would give patients with a deadly and incurable brain cancer called glioblastoma a better chance at survival. Glioblastomas typically affect adults, and are highly fatal because they send out a web of cancerous threads. Even when the main mass is removed, those threads remain despite chemotherapy and radiation treatment. This cancer has caused a number of high-profile deaths including Senator Edward (Ted) Kennedy in 2009, and possibly Beau Biden more recently. Approximately 12,000 new cases of glioblastoma are estimated to be diagnosed in 2017.

“We really have no drugs, no new treatment options in years to even decades,” Hingtgen says. “[We] just really want to create new therapy that can stand a chance against this disease.”

But there’s a problem: brain stem cells aren’t exactly easy to get. Brain stem cells, more properly known as neural stem cells, hang out in the walls of the brain’s irrigation canals — areas filled with cerebrospinal fluid, called ventricles. They generate the cells of the nervous system, like neurons and glial cells, throughout our lives.

A research group at the City of Hope in California conducted a clinical trial to make sure it was safe to treat glioblastoma patients with genetically engineered neural stem cells. But they used a neural stem cell line that they’d obtained from fetal tissue. Since the stem cells weren’t the patients’ own, people who were genetically more likely to reject the cells couldn’t receive the treatment at all. For the people who could, treatment with the neural stem cells turned out to be relatively safe — although at this phase of clinical trials, it hasn’t been particularly effective.

More personalized treatments have been held up by the challenge of getting enough stem cells out of the patients’ own brains, which is “virtually impossible,” says stem cell scientist Frank Marini at the Wake Forest School of Medicine, who was not involved in this study. “You can’t really generate a bank of neural stem cells from anybody because you have to go in and resect the brain.”

So instead, Hingtgen and his colleagues figured out a way to generate neural stem cells from skin — which in the future, could let them make neural stem cells personalized to each patient. For this study, though, Hingtgen and his colleagues extracted the skin cells from chunks of human flesh leftover as surgical waste. “That really is the magic piece here,” Marini says. “Now, all of a sudden we have a neural stem cell that can be used as a tumor-homing vehicle.”…




Resultado de imagem para A Dorid nudibranch (Tritoniella belli) in Antarctica. Photo by Norbert Wu/Minden/National Geographic

Cold and calculating. A Dorid nudibranch (Tritoniella belli) in Antarctica. Photo by Norbert Wu/Minden/National Geographic

The world is full of mundane, meek, unconscious things embodying fiendishly complex mathematics. What can we learn from them?

Margaret Wertheim writes about the cultural resonances of science and mathematics. Her books include The Pearly Gates of Cyberspace (1999) and Physics on the Fringe (2012). She also creates art and science projects, including Crochet Coral Reef, which has been exhibited at the Hayward Gallery, the Smithsonian, and elsewhere. She lives in Los Angeles.

What does it mean to know mathematics? Since maths is something we teach using textbooks that demand years of training to decipher, you might think the sine qua non is intelligence – usually ‘higher’ levels of whatever we imagine that to be. At the very least, you might assume that knowing mathematics requires an ability to work with symbols and signs. But here’s a conundrum suggesting that this line of reasoning might not be wholly adequate. Living in tropical coral reefs are species of sea slugs known as nudibranchs, adorned with flanges embodying hyperbolic geometry, an alternative to the Euclidean geometry that we learn about in school, and a form that, over hundreds of years, many great mathematical minds tried to prove impossible.

Sea slugs have at least the rudiments of brains; they generally possess a few thousand neurons, whose large size has made these animals a model organism for scientists studying basic neuronal functioning. This tiny number isn’t nearly enough to enable the slug to formulate any representation of abstract signs, let alone an ability to mentally manipulate them, and yet, somehow, a nudibranch materialises in the fibres of its very being a form that genius-level human mathematicians didn’t discover until the 19th century; and when they did, it nearly drove them mad. In this instance, complex brains were an impediment to understanding.

Nature’s love affair with hyperbolic geometry dates to at least the Silurian age, more than 400 million years ago, when sea floors of the early Earth were covered in vast coral reefs. Many species of corals, then and now, also have hyperbolic structures, which we immediately recognise by the frills and crenellations of their forms. Although corals are animals, they have only very simple nervous systems and can’t be said to have a brain. A head of coral is actually a colonial organism made up of thousands of individual polyps growing together; collectively, they grow a vascular system, a respiratory system and a crude gastrointestinal system through which all the individuals of the colony eat and breathe and share nutrients. Nothing like a brain exists, and yet the colony can organise itself into a mathematical surface disallowed by Euclid’s axiom about parallel lines. Strike two against ‘higher intelligence’.

Ask any fifth-grader what the angles of a triangle add up to, and she’ll say: ‘180 degrees’. That isn’t true on a hyperbolic surface. Ask our fifth-grader what’s the circumference of a circle and she’ll say: ‘2π times the radius’. That’s also not true on a hyperbolic surface. Most of the geometric rules we’re taught in school don’t apply to hyperbolic surfaces, which is why mathematicians such as Carl Friedrich Gauss were so disturbed when finally forced to confront the logical validity of these forms, and hence their mathematical existence. So worried was Gauss by what he was discovering about hyperbolic geometry that he didn’t publish his research on the subject: ‘I fear the howl of the Boetians if I make my work known,’ he confided to a friend in 1829. To their universal horror, other mathematicians soon converged on the same conclusion and the genie of non-Euclidean geometry was let loose.

But can we say that sea slugs and corals know hyperbolic geometry? I want to argue here that in some sense they do. Absent the apparatus of rationalisation and without the capacity to form mental representations, I’d like to postulate that these humble organisms are skilled geometers whose example has powerful resonances for what it means for us humans to know maths – and also profound implications for teaching this legendarily abstruse field.

I’m not the first person to have considered the mathematical capacities of non-sentient things. Towards the end of Richard Feynman’s life, the Nobel Prize-winning physicist is said to have become fascinated by the question of whether atoms are ‘thinking’. Feynman was drawn to this deliberation by considering what electrons do as they orbit the nucleus of an atom. In the earliest days of atomic science, atoms were conceived as little solar systems with the electrons orbiting in simple paths around their nuclei much as a planet revolves around its sun. Yet in the 1920s, it became evident that something much more mathematically complex was going on; in fact, as an electron buzzes around its nucleus, the shape it makes is like a diffused cloud. The simplest electron clouds are spherical, others have dumbbell and toroidal shapes. The form of each cloud is described by what’s called a Schrödinger equation, which gives you a map of where it’s possible for the electron to be in space…




Hannah Arendt

“Under conditions of terror most people will comply but some people will not… No more is required, and no more can reasonably be asked, for this planet to remain a place fit for human habitation.”

“Never react to an evil in such a way as to augment it,” the great French philosopher and activist Simone Weil wrote in 1933 as she contemplated how to make use of our suffering amid a world that seemed to be falling apart. But modern life is no fairy tale and one of its most disorienting perplexities is that evil isn’t always as easily recognizable as a Grimm stepmother. Maya Angelou captured this in her 1982 conversation with Bill Moyers about courage and facing evil, in which she observed: “Throughout our nervous history, we have constructed pyramidic towers of evil, ofttimes in the name of good.” Joseph Brodsky echoed the sentiment five years later in his spectacular speech on our greatest antidote to evil: “What we regard as Evil is capable of a fairly ubiquitous presence if only because it tends to appear in the guise of good.”

A core cause of this perplexity lies in the fact that while acts of evil can mushroom into monumental tragedies, the individual human perpetrators of those acts are often marked not with the grandiosity of the demonic but with absolute mundanity.

This was the revolutionary and, like every revolutionary idea, at the time controversial point that Hannah Arendt (October 14, 1906–December 4, 1975) made in 1962, when The New Yorker commissioned her, a Jew of who had narrowly escaped from Nazi Germany herself, to travel to Jerusalem and report on the trial of Adolf Eichmann — one of the chief architects of the Holocaust. In 1963, her writings about the trial were published as Eichmann in Jerusalem: A Report on the Banality of Evil(public library) — a sobering reflection on “the lesson that this long course in human wickedness had taught us — the lesson of the fearsome, word-and-thought-defying banality of evil.”

A decade after Arendt established herself as a formidable thinker with her incisive inquiry into how totalitarian tyrants take hold of a people, she writes:

The essence of totalitarian government, and perhaps the nature of every bureaucracy, is to make functionaries and mere cogs in the administrative machinery out of men, and thus to dehumanize them.

It is through this lens of bureaucracy (which she calls “the rule of Nobody”) as a weapon of totalitarianism that Arendt arrives at her notion of “the banality of evil” — a banality reflected in Eichmann himself, who embodied “the dilemma between the unspeakable horror of the deeds and the undeniable ludicrousness of the man who perpetrated them.” In a passage that applies to Donald Trump with astonishing accuracy — except the part about lying, of course; that aspect Arendt addressed with equal prescience elsewhere — she describes Eichmann:

What he said was always the same, expressed in the same words. The longer one listened to him, the more obvious it became that his inability to speak was closely connected with an inability to think, namely, to think from the standpoint of somebody else. No communication was possible with him, not because he lied but because he was surrounded by the most reliable of all safeguards against the words and the presence of others, and hence against reality as such.

The Nazis, Arendt argues, furnished this deliberate disconnect from reality with what she calls “holes of oblivion.” (Today, we call them “alternative facts.”) In a searing testament to the power of speaking up, she considers what the story of the Holocaust — a story irrepressibly told by its survivors — has taught us:

The holes of oblivion do not exist. Nothing human is that perfect, and there are simply too many people in the world to make oblivion possible. One man will always be left alive to tell the story…




by John W. Whitehead, Guest, Waking Times

“We are fast approaching the stage of the ultimate inversion: the stage where the government is free to do anything it pleases, while the citizens may act only by permission; which is the stage of the darkest periods of human history, the stage of rule by brute force.”—Ayn Rand

The torch has been passed to a new president.

All of the imperial powers amassed by Barack Obama and George W. Bush—to kill American citizens without due process, to detain suspects indefinitely, to strip Americans of their citizenship rights, to carry out mass surveillance on Americans without probable cause, to suspend laws during wartime, to disregard laws with which he might disagree, to conduct secret wars and convene secret courts, to sanction torture, to sidestep the legislatures and courts with executive orders and signing statements, to direct the military to operate beyond the reach of the law, to act as a dictator and a tyrant, above the law and beyond any real accountability—have been inherited by Donald Trump.

Whatever kind of president Trump chooses to be, he now has the power to completely alter the landscape of this country for good or for ill.

He has this power because every successive occupant of the Oval Office has been allowed to expand the reach and power of the presidency through the use of executive orders, decrees, memorandums, proclamations, national security directives and legislative signing statements that can be activated by any sitting president.

Those of us who saw this eventuality coming have been warning for years about the growing danger of the Executive Branch with its presidential toolbox of terror that could be used—and abused—by future presidents.

The groundwork, we warned, was being laid for a new kind of government where it won’t matter if you’re innocent or guilty, whether you’re a threat to the nation or even if you’re a citizen. What will matter is what the president—or whoever happens to be occupying the Oval Office at the time—thinks. And if he or she thinks you’re a threat to the nation and should be locked up, then you’ll be locked up with no access to the protections our Constitution provides. In effect, you will disappear.

Our warnings went largely unheeded.

First, we sounded the alarm over George W. Bush’s attempts to gut the Constitution, suspend habeas corpus, carry out warrantless surveillance on Americans, and generally undermine the Fourth Amendment, but the Republicans didn’t want to listen because Bush was a Republican.

Then we sounded the alarm over Barack Obama’s prosecution of whistleblowers, targeted drone killings, assassinations of American citizens, mass surveillance, and militarization of the police, but the Democrats didn’t want to listen because Obama was a Democrat and he talked a really good game.

It well may be that by the time Americans­—Republicans and Democrats alike—stop playing partisan games and start putting some safeguards in place, it will be too late.

Already, Donald Trump has indicated that he will pick up where his predecessors left off: he will continue to wage war, he will continue to federalize the police, and he will operate as if the Constitution does not apply to him.

Still, as tempting as it may be, don’t blame Donald Trump for what is to come.

If this nation eventually locks down… If Americans are rounded up and detained based on the color of their skin, their religious beliefs, or their political views… If law-and-order takes precedence over constitutional principles…

If martial law is eventually declared… If we find that there really is nowhere to run and nowhere to hide from the surveillance state’s prying eyes and ears… And if our constitutional republic finally plunges headlong over the cliff and leaves us in the iron grip of totalitarianism…

Please, resist the urge to lay all the blame at Trump’s feet.

After all, President Trump didn’t create the police state.

He merely inherited it.

Frankly, there’s more than enough blame to go around.

So blame Obama. Blame Bush. Blame Bill Clinton.

Blame the Republicans and Democrats who justified every power grab, every expansion of presidential powers, and every attack on the Constitution as long as it was a member of their own party leading the charge.

Blame Congress for being a weak, inept body that spends more time running for office and pandering to the interests of the monied elite than representing the citizenry.

Blame the courts for caring more about order than justice, and for failing to hold government officials accountable to the rule of law.

Blame Corporate America for taking control of the government and calling the shots behind the scenes.

Most of all, blame the American people for not having objected louder, sooner and more vehemently when Barack Obama, George W. Bush and their predecessors laid the groundwork for this state of tyranny.

But wait, you say.

Americans are mobilizing. They are engaged. They are actively expressing their discontent with the government. They are demanding change. They are marching in the streets, picketing, protesting and engaging in acts of civil disobedience.

This is a good development, right? Isn’t this what we’ve been calling on Americans to do for so long: stand up and push back and say “enough is enough”?

Perhaps you’re right…


About the Author
Constitutional attorney and author John W. Whitehead is founder and president of The Rutherford Institute, where this article first appeared. He is the author of A Government of Wolves: The Emerging American Police State and The Change Manifesto.






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